ELECTRICAL IRRADIATION EFFECTS IN SOLID DIELECTRICS
An annotated bibliography
Bernhard Gross
Instituto de Física e Química de São Carlos , SP
Brasil
1973
- 2 -
The Bibliography lists in alpha-numerical order, by the
name of the first author, about 800 papers on electrical
irradiation effects in solid dielectrics. Nearly all entries
contain a short abstract. An introductory section gives
a short review of the subject matter. Then follows a
List of Contents and a Subject Index ; the latter lists
the same topics, each followed by the entry numbers of
the papers relevant to the subject. The bibliography
covers papers and reports published until June 1973•
The author gratefully acknowledges the assistance of the
Brazilian National Nuclear Energy Commission which has
enabled him to carry out this work .
INTHODUCTION
It has been known for a long time that the electrical properties
of insulating material are adversely affected by exposure to
nuclear radiations» Some beneficial effects may derive from
the fact that radiation-induced currents can be used as a measure of radiation dose rate. Investigation of changes of dielectric
properties is of importance in view of the widespread use of
dielectrics in a nuclear environment and the continuous in crease of the amount of radiation which electrical equipment is
supposed to withstand. A great number of papers has been published on the subject. The present bibliography reviews that part
of the literature which deals with purely electrical effects of
radiation. It omits references to chemical degradation, changes
of molecular structure, and of mechanical, thermal, and optical
properties. It also excludes the field of semiconductors and
semiconductor devices, in particular transistors.
Within the subject field, main topics are radiation-induced oonductivity, radiation-induced currents, and radiation-induced
charge buildup and decay. An adequate understanding of these
effects depends on the results of the basic theory of carrier
injection from the electrodes, carrier transport, trapping, and
recombination, carrier mobility, and of space-charge-limited
currents (Sections I and II) .
Radiation-induced conductivity depends on dose and dose rate.
It is also a function of time and thus is a relaxation effect
characterized by current transients occurring when irradiation
is initiated and when it is discontinued. Behavior of dielectrics
under continuous irradiation differs markedly from that under
pulsed irradiation. A semiphonological theory explains this
behavior in a general way. But reaction varies widely from
material to material and different types of radiation evoque
different response. A wast amount of partially emprirical
literature, difficult to be coordinated, deals with the material
- 4problem. Speoial attention has been given to the behavior
of polymers
} effects of crystallinity have been investigated
in quartz, diamond, alkali halides . Radiation effects are
affecting the performance and reliability of capacitors and
other types of equipment. While most papers deal primarily
with variations of eleotrical resistivity and leakage, in crease of dielectric loss and changes of capacitance have also
been observed (Section III) •
Measurement of transient effects, in particular carrier transit
times, produoed by penetrating and non-penetrating beams is an
important tool for determination of carrier mobility and its
dependence on temperature, on the role played by recombination,
and of the energy necessary to generate a free electron-hole
pair. To investigate dielectric behavior in an extreme nuclear
environment, special high-poirored pulsed machines are being
developed requesting a specialized measurement technology»
They generate pulses in the nanoseo range at exposure rates
of up to 10 ^ R/sec (Section IV) .
Mobility measurements can also be performed by methods in which
a free (electrically floating) surface of a dielectric is
charged by different methods and the subsequent charge decay
is monitored. Charge density on surfaces can be measured by
conventional means (induction method)and by deflection of in —
oident or grazing electron beams»
Carrier emission from the
surfaoe of highly oharged dielectrics has bean observed (Section V).
Carrier injection from an energized electrode or irradiation
with non-penetrating particle beams produces space charges in
the bulk of the material. Direct determination of space-char-ge
density can be oarried out by various, destructive methods in
whioh the surface of the dielectric is gradually removed by
chemical (etching) or mechanical (sectioning) procedures. The
method distinguishes between dielectric polarization and
space charge polarization. Purely electrical, non-destructive
_ 5 ™
methods have also been developed whioh allow determination of
the average spaoe-charge depth by measurement of currents
and voltages drawn from the electrodes of a special capacitor
system (Section VI) .
Absorption of monoenergetic high-energy electron beams is
characterized by range straggling and backscattering. Absorption
curves are S-shaped. Experimental results can be represented
by relatively simple range-energy relations. They have been
calculated in detail by modern computational methods* The
differential range distribution function and the corresponding
energy and oharge deposition profiles can be directly monitored
by electrioal charge-recording methods and by thin-film dosimetric procedures. The range distribution in dielectrics may differ
from that in metals due to the retardation effect of the internal
space charge field set up by the trapped charge. This field can
also lead to charge emission from the dielectric surface, the
generation of internal voltages exceeding the accelerating
voltage of the incoming beam, and the production of internal
breakdown. Space charge values can be measured by mechanicsilly
triggered breakdown. Charge decay is a thermally activated
process and charge measurements by means of thermally stimulated
currents has become a routine method which gives also information
of activation energies and trapping levels. Breakdown and charge
effects are also produced by proton and ion bombardment. A theory
of charge movement and dissipation has recently baen developed
for simple charge configurations .(Section VTl) .
High energy X-rays and Gamma rays can cause intense electrical
effects via secondary Auger, photo- and Compton electrons- The
theory of these effects has recently been developed in considerable
detail. It is complemented by direct measurement of forward and
bachsoattered radiation flux and of flux distribution at surfaces
and interfaces. Space charge buildup is observed in dielectrics
due to the absorption of the primary photons and the corresponding
_ 6 variation of the accompanying electron flux. It is particularly
intense in samples whose thiokness considerably exceeds the
average photon ra.nge $ it then might lead to internal breakdown
whose occurrence in hot cell window glass first called attention
to the effect. This type of dammage can now be avoided by in creasing the conductivity of the glass and thus reducing its
electrioal relaxation time. Other annoying manifestations of
photon-induoed eleotron currents are the polarity effect observed
in ionization chambers operating in the build-up region and the
occurrence of unwanted noise and signals in coaxial cables placed
in a nuclear environment» The complex of phenomena connected with
electron currents set up by a directional photon radiation flux
is now known under the name of Comptor. current or photo-Compton
current. Theory and measurement of these currents are now fairly
well established. The property of photon radiation to generate
Compton currents has allowed the development of special dosimetric
methods and the construction of Compton dosemeters. Several
types of such instruments have come into use, the vacuum diodes
and the dielectric diodes. Dielectric diodes have two electrodes
separated by a dielectric whose thickness is considerably greater
than the maximum eleotron range» They are well suited for measurements under
extreme conditions and now are routinely employed
for nuclear burst dosimetry and monitoring where theyhave replaced
the vacuum type instruments. Personal dosemeters have also been
constructed on these principles. The measurement of thermally
stimulated currents and voltages, in particular those produced by
maintaining a temperature gradient along the sample, continues to
be a useful research tool (Section VIII) .
Electrical radiation effects oan be used in a variety of other
devices and systems. Intense irradiation and concomitant application
of an external polarizing field can produce electrets capable of
generating self-sustained electric fields over long periods of
time. Sectioning methods have been used to determine the charge
distribution in such radioelectrets. Irradiation of a thermo-
- 7electr9t by photon or neutron radiation has been found to destroy
the polarization of the eleotret ) dosimetrio methods based
on this effect have been developed. Other such methods are based
on the lowering of the electrical resistance of insulators during
irradiation, on the change of polarization of ferroelectric
substances, and others. Systems set up to favor the generation
of currents by electron or photon radiation are direct conversion devices or nuclear batteries $ they are high-voltage, highimpedance
sources. Irradiation has also been found to lead to
ignition of conventional explosives. Finally mention is to be
made of HOS (Metal-Oxide-Semioonductor Systems) where high and
long-lasting space charges are produced in the oxide by nuclear
radiations (Section IX) .
- 8 LIST OF TOPICS
I
1
2
3
4
-
Basic Aspeets
Band Gap Model
Trap Characteristics
Carrier Generation and Recombination
Thermostimulated Currants. Glow Curves
II - Space-Charge Limited Currents
1 ~ General Theory.Electrode Injection.
2 - Transients. Mobility Determination.
3 - Trapping Effects
III
1 2 3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
- Badiation-Induoed Conductivity
Early Measurements
Prompt and Delayed Effects.Theory.
- Experimental Results,General .
- Polymers
- Different Materials(Alkali Halides,Crystals,Others)
- X-rays and Gamma Bays
- Electrons
- Protons,Neutrons,Alpha Particles
- Radiation Effects on Components and Equipment
- Hadiation Effeots on Dieleotric Properties
IV - Transient Radiation Effects. Pulsed Measurements.
1 - Technology of Pulse Generation. Diagnostics.
2 - Theory
3 - Penetrating and Non-penetrating Radiation Effects
4 - Mobility Determinations.Recombination.
V
1
2
3
4
-
Surface Charge Effeots
Surface Charge-up,Soannins Methods, Charge Decay.
Surface Discharges
Corona,Ion Charging,Hot Electrons,Photons.
Mobility Determinations
VI- Space Charge Diagnostics
1 - Sectioning Technique.Etching.
2 - Electrical Methods
VII - Penetrating Particles
1 - Electron Transmission and Scattering.Range-Energy Relations.
2.1 - Electron Energy and Charge Deposition Profiles
2.2 - Electron Range Reduction Effects
3 - Electron Charging and Breakdown, Lichtenberg Figures.
4 - Space-Charge Buildup.Charge Storage and Release.
5 - Space Charge Theory.Floating Space Charges.
6 - Protons.Ions.
7 - Thermovoltaic Effects.Thermally Stimulated Currents.
VIII - X-Rays and Gamma Rays
1 - Early Observations
2 - Electron Production and Scattering in Different Materials
3 - Surface Effects. Interfaoe Effects.
4.1 - Space Charge Buildup and Breakdown* Polarization.
4.2 - Electrical Properties of Shielding Glass
5 - Irradiation Effects on Cables. Noise.
6 - Compton Currents. Theory and Measurements.
7 - Vacuum lonization Chambers
8 - Surface lonization Chambers.Build-up Region, Polarity Eifect.
9 - Compton Vacuum Diodes
10 - Compton Dielectric Diodes
11 - Thermovoltaio Effects. Thermally Stimulated Currents.
IX - Special Problems
1 - Radioeleotrets
2 - Electret Dosiraetry
3 - Various Dosiraetrio "ethods (Photodielectric Effect,Pyroelectric
Effect,Ferroelectric Methods. Surface Barrier Methods,Resistivity
Effects, Solid State General)
4 - Neutron Dasimetry
5 - Nuclear Batteries. Direct Conversion Systems
6 - Ignition of Explosives
7 - MOS Structures
- 10 «
I - BASIC ASPECTS
1.1 - Band Gap Model
50,299,343,464,465,466,561,714
1.2 - Trap Characteristics
50,278,282,353,354,399,445,550,554,561,582,614
1.3 - Carrier Generation and Recombination
9,102,113,114,147,282,317,318,319,336,343,363,365,517,561,562,576,595
1.4 - Thermostimulated Currents. Glow Curves.
52,65,66,151,192,243,257,297,299,364,497,535
II - SPACE-CHARGE LIMITED CURRENTS.
11.1 - General Theory. Electrode Injection.
32,33,35,83,182,280,285,424,428,445,462,522,523
11.2 - Transients. Mobility Determination.
45,209,285,428,498,522,523
11.3 - Trapping Effects.
33,45,424,554
III - RADIATION-INDUCED CONDUCTIVITY
111.1 - Early Measurements.
494,560,579,580
111.2 - Prompt and Delayed Effects. Theory.
28,29,47,48,92,94,lOl,lO3,lO6,123,127,128,135,l8O,198,2OO,2O4,275,276,
3O2,3O3,319,535,578,587,597,6O7,622,671,7Ol,7O2,713,723
111.3.1 - Experimental Results, General.
79,273,275,276,3O3,32O,322,323,328,331,341,342,346,355,379,443,485,
486,487,49O,514,515,516,536,597,62O,65Í,694,699,7O8,7O9,71Ô,727,729
111.3.2 - Polymers
2,3,5,28,30,47,48,92,99,100,101,106,175,176,177,178,179,198,200,204,
272,274,284,317,324,381,437,453,511,512,552,671,673,691,712,724,725,
726
111.3.3 - Different Materials(Alkali Halides, Crystals, others)
7,27,59,6l,84,9O,llO,lll,112,12O,144,156,19O,193,281,352,4O2,4O3,4O4,
537,621,623,665,669,672,
III.3«4 - X-Says and Gamma Bays
2,3,16,24,27,28,39,85,99,101,110,111,112,146,156,175,176,177,178,190,
200,204,253,272,281,284,324,381,400,437,444,453,511,512,621,623,649,
669,686,687.712,724,725
III.3.5 - Electrons
15,59,61,90,92,106,127,144,146,147,247,352,537,665
III.3*6 - Protons, Neutrons, Alpha Particles
7,39,84,99,104,151,275,314,316,440
III.3«7 - Radiation Effects on Components and Equipment
49,93,lO3,lO5,123,128,172,l85,l86,255,256,3O5,3O6,344,35O,357,36l,367,
369,372,392,393,396,41O,411,413,4l6,451,495,5O3,513,5l8,519,526,674,7O6
III.3*8 - Radiation Effects on Dielectric Properties
5,41,68,85,86,89,91,94,95,141,186,187,210,256,295,296,322,329,348,349,
349,35O,351,356,374,38O,392,4O1,4O4,4O5,413,414,417,422,435,436,446,489
5O1,51O,518,539,549,566,577,6O7,617,622,659,68O,711,73O,736
- 11 IV - TRANSIENT RADIATION EFFECTS. PULSED MEASUREMENTS.
IV.1 - Technology of Pulse Generation. Diagnostics.
67,129,130,422,432,438,524,625,627,658,689,704
IV. 2 - Theory
498,519,581
IV.3 - Penetrating and Non-penetrating Radiation Effects
29,141,184,2l8,366,396,4O5,411,4l8,43O,431,438,498,5O4,5O5,5O6,5O7,
5O8,5O9,518,519,52O,525,582,583,584,585,6O3,6O8,656,657,664,7O1,7O2
IV»4 - Mobility Determinations. Recombination.
124,363,364,430,431,582,583,584,585
V - SURFACE CHARGE EFFECTS
V.I - Surface Charge-up, Scanning Methods, Charge Decay
12,115,117,132,133,1741248,249,353,354,389,441,455,550,571,695,698,
715,716,717
V.2 . Surface Discharges
14,40,70,116,118,220,696,697
V.3 - Corona. Ion Charging. Hot Electrons. Photons.
12,14,31,35,36,37,38,248,325,326,327,353,354,374,441,496,550,551,
582,,583,584,585,652,657,707
V.4 - Mobility Determinations
31,117,118,132
VI - SPACE CHARGE DIAGNOSTICS
VI.1 -Sectioning Technique. Etching.
134,241,338,406,407,408,420,478
VI.2 - Electrical Methods
26,244,245,246,247,289,334,591,592,613,614,669,678
VII - PENETRATING PARTICLES
VII.1 - Electron Transmission and Scattering. Range-Energy Relations.
42,43,44,56,57,75,82,lO7,145,149,155,l88,2O5,228,25O,258,358,359,388,
423,427,586,606,613,641,642,643,644,645,676,721
VII.2.1 - Electron Energy and Charge Deposition Profiles
8,8O,98,lO8,15O,217,227,269,27O,368,373,397,398,415,434,547,563,6l5,
627,641,642,644,645,661,666,676,677
VII.2.2 - Electron Range Reduction Effects
56,81,148,239,247,269,270,362,394,415,558,643
VII.3 - Electron Charging and Breakdown. Lichtenberg Figuras.
6,63,122,131,191,195,197,201,223,313,385,419,451,454,457,488,548,
555,600,653,667,681
VII.4 - Space Charge Buildup* Charge Storage and Release.
1,25,63,72,73,78,133,183,184,221,222,230,231,239,244,277,304,456,457,
458,459,46O,461,462,477,529,588,589,59O,591,592,593,668,682,7O5,722,734
- 12 VII.5 - Space Charge Theory. Floating Space Charges.
157,158,159,460,461,715,716,717
VII.6 - Protons. Ions.
119,121,286,386,387,398,420,439,440,602
VII.7 - Thermovoltaio Effects. Thermally Stimulated Currents.
183,208,222,477,529,589J59O,591,592,594,735
VIII - X-RAYS AND GAMMA RAYS
VIII.1 - Early Observations
4,23,206,44,500
VIII.2 - Electron Production and Scattering in Different Materials
10,58,69,77,136,137,139,189,312,390,426,611,683,684
VIII.3 - Surface Effects. Interface Effects.
189,254,335,,350,375,390,442,690
VIII.4.1 - Space Charge Buildup and Breakdown. Polarization.
l,2O,21,22951,lO9,14O,152,191,194,231,238,243,263,265,266,267,268,
315,337,351,370,371,377,378,395,449,471,472,478,499,542,543
VIII.4.2 - Electrical Properties of Shielding Glass.
140,152,194,260,271,370,409,549,565,728
VIII.5 - Irradiation Effects on Cables. Noise.
4,54,55,212,367,412,538,564,618,619,626,731
VIII.6 - Compton Currents. Theory and Measurements.
62,77,88,125,126,226,237,238,242,294,3OO,4O1,42I,447,449,611,679,7O8
VIII.7 - Vacuum Ionization Chambers
139,142,291,382,383,384,616,655,656,657
VIII.8 - Surface Ionization Chambers. Build-up Region.Polarity Effect.
23,311,321,339,429,553
VIII.9 - Compton Vacuum Diodes
13,17,l8,19,74,96,97f13O,138,142,206,290,307,308,309,310,332,333,467,
532,541,660,693
VIII.10 - Compton Dielectric Diodes
76,143,17O,196,199,2O2,224,229,232,233,235,24O,242,279,293,294,298,
3Ol,36O,475,479,48O,48l,484,545,559,568,569,72O
VIII.11 - Thermovoltaic Effects. Thermally Stimulated Currents.
29,134,171,192,207,225,257,259,261,262,264,376,452,468,469,476,491,
492,493,542,,543,598,648,650,654,718
IX - SPECIAL PROBLEMS
IX.1 - Radioelectrets
157,158,159,2O8,214,215,2l6,234,236,474,476,483,521,588,7OO
IX.2 - Eleotret Dosimetry
153,154,171,234,252,287,433,452,473,527,528,534,546,663,719
IX.3 - Various Dosimetric Methods(Photodielectric Effect,Pyroelectric
Effeot,Ferroelectric Methods.Surface Barrier Methods,Resistivity
Effects, Solid State General)
11,53,71,173,181,211,287,292,336,347,391,401,45O,482,53O,533a,567,570,
646,647,662,692
- 13 IX.4 - Neutron Dosimetry
46,52,60,203,219,229,310,340,341,342,345,545,568,569,612,670,692
IX.5 - Nuclear Batteries.Direct Conversion Systems.
87,213,228,233,251,447,448,449,502,533,544,556,557,559,573,574,575,596
IX.6 - Ignition of Explosives
425,531
IX. 7 - MOS Structures
533a,54O,572,598,599,6OO,6O4,605,609,610,624,732,733
IRRADIATION DAMAGE TO GLASS
J.A.Aboaf jJ.R.HenslerjH.
Bausch and Lomb Inc.Rochester,KY.TID-17227,Octo.I962
Measurement of space charge buildup in electron-and gamma
irradiated lead silicate,phosphate,silica and pyrex glass,
including measurement of dielectric properties and do
h
" ' conductivity. Results do not support a space charge
effec,t, -but iddicate that effects do occur in the
bulk of the glass.
THE ANOMALOUS AND STHADY STATS CONDUCTIVITY OF P0LYT3TRAFLUOROSTHYLENÍ2 UNDER IRRADIATION
V. Adamoc. Dielectrics (GB), Vol.1, No.3,159-60 (Aug.1963)
With X-ray equipment as the source of radiation the current
flowing in polytetrafluoroothylne sheet was measured using a
wide range of dose rates(1O~3-IO' rad/sec) at energies of 15,30
and 38 keV. It was found that the steady state conductivity and
also the induced anomalous conductivity rose under the action of
the irradiation and that the rate of decay of the anomalous conductivities at dose rates up to 0.4rad/sec was similar to that
without irradiation.
NATURE OF ANOMALOUS CONDUCTIVITY OF POLYMERIC INSULATING
MATERIALS
V.Adaraec
Proc.'
ÍIEE(GB) 1] 2,405(1965)
L...J
Measurements of conductivity under irradiation. Electric
stresa was applied only after the radiation-induced
polarisation could be assumed to have reached equilibrium,
i.e. •gflKTc some hours after beginning of irradiation with
X-rays.Doses varied! from 0 to 400 ft/s.Several absorption
and transient effects were observed. Intei-pretation in
terms of a Maxwell-Wagner mechanism is given.
.ON THE MEASUREMENT OF SMALL,RADIATION INDUCED CURRENTS
G.D.Adams,H.E.Jones
Radiation Research
Spurious currents were observed in insulators during X-ray
irradiation. Measurements of transients observed with
co-axial cables are also referred to.
TEMPORARY CHANGES IN ELECTRICAL PROPERTIES OP POLYMER
DIELECTRICS DUE TO IONIZING RADIATION
V.Adamec (Cables and Insulating Materials Res.Inst.,
Bratislava,CSSR)
J.Polymer Sei. A-2, £,1241(1968)
Measurements of conductivity,permittivity,and dissipation
factor on polystyrene,low-density polyethylene,poly(ethylene
terephthalate) and polytutrafluoroethylene under irradiation with X-rays at exposure rates from 0.004 to 400
R/sec are presented.The radiation-induzsed anomalous conductivity as well as the induced dielectric loss are interpreted by Maxwell-Wagner polarization due to radiation
imbalance in surface layers of specimen. The nature of the
steady-state conductivity is also discussed.
C
t
DIRECTIONAL BRKAKDOTO IN HaCl CRYSTALS BOMBARDED WITH
ELECTRO1TS
I.Agarbiceanu, I.Teodorescu
Rev.Roum. 12^,927(1967)
Bombardment of NaCl crystals vrith electrons of meditun
energy (33«5 to 44 keV) results in the appearance of the
following effects» Lichtenberg patterasj starlike figures,
melting structures, and dislocations. For these to be
revealed, the electron beam density must b e sufficiently
high in order to create, on the surface,strong electric fields
strong enough to produce electron avalanches. The directional
breakdown figures obtained are alraost identical with these
obtained by scratching or by pressing the surface of the
crystal by a sharp point.Characteristic values for the electron
current are about 400 to 1 000 microA/cm 2 at 50 keV and 4 to
10 min irradiation time. In some experiments, spot irradiation
of short duration was used.
;
/
^
|
j
p>-
CONDUCTIVITY INDUCED IN DIAMONDS B Y ALPHA PARTICLES
BOMBARDMENT AND ITS VARIATIONS AMONG SPECIES
A«J.Ahearn
Alpha particle bombardment is used to establish an internal
field corresponding to 480 V/cm.
24636
ENERGY DISTRIBUTION OF TRANSMITTED SECONDARY ELECTRONS FROM POROUS KC1 FILMS; Akagi, M.;
Yoshida.S. (Tohoku Univ., Sendat). J. Appl. Phys.; 43: No. 3 ,
880-5(Mar 1972).
Energy distribution of secondary electrons from three types of
porous films (porous KC1 films, porous KC1 films with Intermediate thin Al layer, porous KC1 films containing small amount
of amorphous Al) was measured by an ac retarding-field method.
The half-width of each energy distribution curve was found to be
about 10 to 20 eV. The surface potential of these films was also
obtained from the rising point of the energy distribution curve. A
single relationship between surface potential and yield and independent of collector voltage was found for constant primary energy.
Decay characteristics of the surface potential of three films after
ceasing the primary electron bombardment were similar to each
other. Secondary currents from a porous KC1 film containing a
small amount of amorphous Al were found to be considerably more
stable compared to those from two other films. A secondary
electron emission is proposed using a channel electron multiplier
model, (auth)
»
'
O
°
Í
I
RADIATION EFFECTS IN POLYKEBS
R.S.Alger
In: Physic3 and Chemistry of the Orranic Solid State.
D.Fox ed., Chapter IX, i ( Interscience Publishers,N.Y.^965
SssBiaSsiixdisBHSSfcBKXHff ftadiation Induced Transients
a
d i s c u s s e s Yield of Free E l e c t r o n s ,8ange of Free
E l e c t r o n s , E l e c t r o n T r a p s , U n t r a p p i n g and N e u t r a l i z a t i o n .
!
i
i
«
ELECTRON PRODUCTION AND TRANSPORT IK ELECTRONIC MATERIALS
IN A PULSED NUCLEAR ENVIRONMENT
H.3.Almond,V.K.Schinidt(Boein£ C o . S e a t t l e )
D2-98TS-3(3ect.Il)
j In: Contributions to the state-of-sxi the art of transient
" radiation effects' in electronic parts and materials.
Vol.2. 1962 D2-9S73-3)
;
!
!
J
1
The chief source of high energy electrons from a fission
spectrum is the Conipton effect .7:.e àensity of the Compton
recoil electrons from a plate of thickness large compared to
electron rant;e but small compared to lamina range increases
slo-.vly v/ith atomic number.Expressions based on the Kukla
,-;ai:iMa spe truu are derived for the net current flow fron a
pi ato, and net rate of creation of sp&ce charge within the
plate, as a function of the thickness and composition of the
plate and others betv/ecn it and the s&mma source. An expression
io also derived to take into account the backscatter and
secondary electron production betv/een plates of the same and
dissimilar materials.Results of experiments xi±ii at Kukla
are presented,Disagreement oi theory and experiment for bare
nl.vtes are •attributed to unexpectedly high electron scatter
10
anisotropy in the test area and to the backscatter effects I inch were not taken into account. Ketals,graphite,and'
polyetuylene were tested.i-he two last-named materials
are susceptible to neutrins as well as to gamma rays.
31710
DETECTION OF NUCLEAR RADIATION USING
THE CUMULATIVE PHOTODIELECTRIC EFFECT IN CADMIUM
SULFIDE. Alworth, Charles Wesley. Norman, Okla.; Univ.
of Oklahoma (1969). 122p.
Thesis.
The field of nuclear radiation detection is limited at the low
energy scale. Present day radiation detectors have a practicallower limit of approximately 1 keV for alpha, beta, and gamma.
This lower limit is due to noise in the detectors themselves and
their associated electronic circuits. The present study of xradiation from color television receivers requires a lower energy range from the radiation detection equipment. Future applications of radioisotope tracer techniques will need a high
sensitivity radiation detector. The cumulative pbotodielectric
effect uses the ac mode of radiation detection to improve the
signal to noise ratio, and extend the lower energy limit to the
theoretical limit of 2.53 cV, which is the value of the bandgap in
cadmium eulflde. Cadmium sulfide exhibits the photodielectrlc
effect between 0 and 200°K. This work makes use of this property
to study the ac mode of radiation detection. The work first traces
the background of nuclear radiation detectors, and examines the
only previous work In the area of the ac mode. The work also
discusses the interaction of radiation with matter. Next a dlBcussion of the electron traps In cadmium sulfide which are responsible for the photodleloctric effect are discussed. Primary emphasis Is on the effect of radiation on Uie dielectric constant of
cadmium sulfide, and a series of equations is derived explaining
the change in the dielectric constant due to radiation. Experimental procedures are explained, along with the preliminary
design problems and preparations. Techniques for measuring the
change in dielectric constant using radiofrequency electromagnetic
waves are explained. Finally, the work demonstrates that the
cumulative photodlelectrlc effect can be used to detect low Intensity, low energy beta particles. In this case the 6ource of radiation used was radioactive carbon-14. (Disser. Abstr.)
I
l
//
'
i
!
ÍP-G^TIV?: ION BOI.IBARDI.KNT OF INSULATORS
ÜUR1'\AC];; CHAKG,J~UP
G. A.Anderson, H. J.Rod.on, C. ]•'.Rohinnon
J.Ar>pl.Phyp>. £ 0 , 7 4 2 0 ( 1 9 6 9 )
TO ALLEVTA'J'ii
•:: VP.GTIV.WE p:*::R3Y SENSITIVITY OF LASL iiivvr/icTi
: . C . A n d c r r o ! i , L.P.lh-.ekcr
S o p . 2GG-11R3-2125, S-357-R CFtí.
Calculation;; for
i n f i n i t e pca';-.llel pli-ite ^e owe t r y .
1 COMPARATIVE EFFKCTS OF I Oil BOKBAPaJUUNT AND PARTIAL /
I DISCHARGES Olí POLYETliYLEIiK FOILS
:
A.Antoniou,Bui Ai,R.Lacoste,C.2<:a5 r oux
C.H.HeT>à.Seaii.Acad.aoi. B 274955 (l<;72
'
/A
ELECTROi^BOMBARTOIENT C015DUOTIVITY OP DIELECTRIC FILMS
P.Ana'baoher/.V.Ehron'bGrg
Proc.Phys.Soo.(London) A 6^,362(1951)
Reports measurements with lov/ energy(up to 50 keV)electrons.
The main not effect of the electrons is excitation and ionizatic
of atoms along the electron path.Some secondary electrons andh"áí
will migrate through crystal until they recombina or are
trapped or reach the electrodes.Trapping and recombination are
illustrated by the existence of a critical voltage V necessary
to observe a significant effectsbelow V t h e pairs recoiabino
near Xiheir places of origin because charges carried beyond
the irradiated region(here supposed to be considerably smaller
than thes!Ê$.s&si thickness ) are trapped and set up a canta
counter space charge field, preventing further carrier movement.
.
.
.
.
.
.
.
,
ftp
f>
CONDUCTIVITY CHANGES IN DIELECTRICS DURING 2.5 MEV
; X-RADIATION
F. D. Armi ste ad, J. C, Pennock, L. V/.Mead
Phys.Rev. 16,860(1949)
'
The volume conductivity of polyvinyl chloride,vinylidene
chloride, and polystyi-ene have been measured. The observed
increase of conductivity is interpreted as caused by a re auction of the barrier at the electrode-dielectric interface. The increase during irradiation was rather fast,but tha
recovery time after cessation of irradiation was of the order
of hours.
rn^^S?,£
0 4 3 )
ACCOMPLISHMENTS OF
COMPTON STUDIES PROGRAM. FISCAL YEAR 1965
Artuso. J. F. (Edgerton, Germeshausen and Grier Ino
Santa Barbara. Calif.). Sept. 196". Contract AT(29-i>1183. 48p. Dcp. mn; CFSTI S2.00 cy. $0.50 nin
•
The theory used to calculate the luantum eflVicncv of • f
^various metals as a function of incijyot phot.,n ,-nerev is '
presented. The concisions drawn fr'.m ihis -h.-ory were
2™ , t o b e l n v e r y Kood agreement with exp.- cental data'
tor low-Z materiala the calculated quantum -j'.tieicncy is
within 2 percent of the measured value. A U i w n i e a l dlscussion of the resolution of an elect rostatic n-arding field
Bpectrometer is also presented, and :• numlx- ..f integral
electron spectrum curves aro shown, (auth)
I ~t
'
PROGRESS REPORT ON COKPTON STUDI£S(annual,!965)
J.F.Artuso
;
Edeorton,(3ermerahausen,Grier(Cal.) EGG-1183-Í-J43
USA 20,9695(1966)
53197
(ECiG-1183-2277) LINEAH1TY, TIME DOMAIN IÍEFLECTOMETEJ1, AND FOUIUEIi ANALYSIS STUDIES OF AN
EVACUATED COMPTON DETECTOK. Artuso, J.; Stevens, J.
(EG nnd 0, Inc., Goleta, Calif.). Sep 1971. Contract AT(29-1)1183. 72p. (S-S-M-K). Dcp. NTIS.
For Calllornia Univ., Uvermore. Lawrence Livormore Lab.
The experimental procedure used to measure the dependence of
the L-125A detcctor'B relntlvo sensitivity on tile width of Incident
gamma pulses is described. When exposed to bremsstrablung
pulses whose widths were changed from 1 nsec to 4 iisoc, the
detector was found to be linear to within ±C%. The value of the
time domain rcflectomctry (TDR) technique for Improving the time
response of the L-125A detector was established by comparing its
results with those obtained by measuring the frequency response
of the detector using a 50-psec bremsstrahlung pulse. These
studies show that properly interpreted TDR techniques can give
Information that can be applied to the design of detectors with a
higher frequency response than that of the L-12SA detector. The
peak linear output current of 1 1 L-Í25A detector was also measured and results arc present: i on the Influence of excitation
amplitude on detector linearity, (auth)
/
.*
/y
'
0? POLYSTYEKlíü) PREVIOUSLY S13BJECÍKD TO
ACTION OP GAMI-ÍA RAÜIATICIT
Cí.Asch, Kario-Claude F o l i x , R.Onearo.
(
j
L.
Sa.-r.plos were i r r a d i a t e d at io5r/h u? *o l6o h.
Subsequent application of a polarizing f i o l i up to 20 kV/cm
during 4 to 5 d:.-ys produced s, persistent polarizp.tion. One
cuartor of i t decays in short c i r c u i t dui?ii:g v/ithin 2 db,ys,
2HX If tho sample i s exposed F.£;ain to rarama radiation, the
shorted s?jnple i s discharged cotnpletely v/ithln loss than ono
1
hour.
I
i
SPACE CHARGES IN IRHADIATKD DIKLSCÍSTCS
O.AaohjK.C.Felix,S.OngaTO
^
Industries Atomiquos li° 9/lO,p.8o,K° 11,p.68(1966)
Survey article on effects of electron 'bom'bardment and
gamma irradiation, including Compton current theory.
j"
J
. I
'
-
|
'•
.
I
'
(fj OF POLYTiniiU ATC3) P 0 L Y S T Y M 2 AFTFÍ
lli'UDIATJCK
Lab. E3 ectroniriue, Facul 1.<5 dos Seiences, Lyons, Frenoe
Physica Status Solidi 21,49(1966)
Reports a study on tht|behavior of radioelectreta of polythene
and nolysityrrene.Samples nre irradiat d and conoommittantly
or subsequently exposed to an external electric field. Surface
charges ara meij-.-iurf.-d "by the induction plate method. Stable
heterochíu-jes are found in all caoos. Charge; values sre
calculated under the assumption that ± H E X initially towunâx
ií3tss*j:eHE/.ro?B trapped electrons are untrapped by thermal
excitation.
1
DOSE kSASUHifl.IBiJTS Hi THE BUILDUP HJEGION K>H COBALT -60
RADIATION
K.AspinjR.G.Bakei-jH. B.Johns
Journal de L1Association Canadienne des Radiologistes
8^,, December 1957
Radiation absorbed in the build-up region is usually
measured by a thin windov,parallel plate ionization
chamber.Tliiu absorber sheets placed over the vindovr serve
to increase the depth Of the chamber. Dosage measureraenta
made in this manr.ar have been found to depend on the
polarity of the collecting voltage.This polarity effect
is greatest at the surface. The effect is described and
interpreted in terms of forward driven Compton electrons
:'
j
!
•
1471
GAMMA RADIATION EFFECTS ON ELECTRIC CONDUCTIVITY OF ROCHELLE SALTS AND AMMONIUM DIHYDROPHOSPHATE. Azizov, S. A.; Gafurov, Kh. M. (Tashkent State
Teachers Inst.). Izv. Akad. Nauk Ujb. SSR. Ser. Flz.-Mat. Nauk,
No. 3.-8,1(1969). (In Russian).
Gamma radiation effects on the electric conductivity of the
Rochelle salt and ammonium dihydrophosphate (ADR) were studied
at room temperature to 2000*C, using 5 x 5 x 3 mm crystals of
Rochelle salts irradiated with y rays at 6.8 x 10s r/hr and ADR
irradiated at 12.6 Mr/hr. At room temperature, the electric con-
j
:
1
!
J
I
Í
ductivity of ADR changed very little, while
In Rochelle salts It f
increased
from 11.4 x io~" ohm"' • cm"1 for nonirradiated to 1.6 <
6
1
10" ohm" cm" In specimens irradiated with 80 Mr. A linear •!
dependence of electric conductivity was observed up to 40 Mr in
Eochelle salt and up to 200 Mr in ADR. (R.V.J.)
\
-ON-THE.-APPEARANCE. OP.. AN. EMP. INCIDENT TO ANNEALING OP
THE BETA-IRRADIATED ALKALI METAL HALIDS CRYSTALS
V. A. Avonin, I. A. Vasilev, G. A. ?.Iikh?.chcmko, B. I. Plachenov
Izv.Àkad.Nauk. USSR,Ser.Piz., ,20,679(1966)
US'
Crystals ireadiated v/ith beta-rays at 90°K exhibit ,
uvon heating, a free surface charge at the surface
of incidence (im addition to the optical glow curve).
The charge is believed to result from a nonuniform •
distribution over the sample thickness of trapped
charges.
B
THEORY OF A N ELECTROSTATIC ENERGY SUPPLY; ANALYSIS OF NONDESTRUCTIVE
McTHODS FOR THE MEASUREMENT OF INTERNAL CHARGES.
Baerwald, H . G .
Albuquerque, N . Mex., Sandia Corp., Mar., 1960. 8? p. (SCTM 241A-59-(51)).
Physical background, analysis, and tentative design of a type of electrostatic energy
supply based on charge embedment in insulators is discussed. Potentially available emf's
and charges look attractive. A class of electromechanical dynamic methods enabling
one to measure entrapped charges non-destructively is proposed and analysed In detail.
They ore based on electrostriction. They are also capable of high precision determination
of electrostatic constants.
.
9
/
I
GAMMA-INDUCED ELECTRIC CONDUCTIVITY IN FUSED SILICA
K.Bagge,U.Jansen
Atomkernenergie .10,197(1965)
Measurements were made for dose rates of 1 to 2 x 10°r/h.
Considerable variations were found getween different samples
with no apparent correlation with the degree of purity of the
quartz glass. Decay rates of conductivity after cessation
of irradiation are also reported.
j
I
|
j
j
;
'•
|
'
j
!
j
I
I
325Z6
LONG-TKRM RADIATION-INDUCED CONDUCTIVITY
IN POLYETHYLENE TEREPHTHALATE. Ballard, Lewis Franklin. Durham, N. C ; Duke Univ. (1969). 92p.
Thesis.
Radiation induced conductivity (RIO In polyethylene terephthalate
(PET) is studied in amorphous and partially crystalline samples
exposed to 60Co gamma rays. Emphasis is placed on persistent
RIC which exists for a long period of time after exposure. The
drift mobility of holes in PET is observed by a pulsed photoconduclivity technique to be near 2 x 10~s cm2 v"1 sec" 1 . By tne
same method, the carrier mobility in dimctliyltcrephthalatc (DMT).
a model compound for the PET polymer, is found to be near 0.8
cm* v"1 sec" 1 for holes and 0.05 cm2 v"' sec" 1 for electrons. Significant reduction in the mobility after irradiation is observed.
The primary source of the long term RIC which becomes significant at radiation doses above 10s rads is concluded to be an increase in the carrier concentration. A model and experimental
evidence are presented which relate this increased carrier concentration to free radical accumulation in doping levels lying
within a few kT of the valence level. These carriers move through
PET by a hopping process which is limited in the steady state by
traps located near 1.0 eV having a density of about 10ls cm"3.
(Diss. Abstr. Int., B)
7 "7
<j „
/ ff
*
RADIATION INDUCED TRAPPED CJIARGE CARRIERS 111 ORGAITIC
POLYMERS.A liODEL OP THERMOELECTRIC CUKffiirT GENERATION I
J .13 .Barnes, F. E. Hoecker, L. Kevan
J
Radiation Research 4o.,235-254(l969)
•
.Trapping and detrapping of radiation-induced charge
carriers in PKÍJA.PVC. and other polmors were investigated.
Thermoelectric currents were generated after irradiation
by thermally stimulating the release of the trapped charges
and subjecting them to a temperature gradient* Heating
similarly irradiated samples in the absence of a tempera ture gradient produced a tenfold reduction of the
observed current. The charge carriers were determined to
be positive from the polarity of the colder^electrode.
To observe these currents, electrons liberated during
irradiation had to be trapped to prevent
recombination
with trapped positive charges. This trapping is not done
by the polymer matrix of PKKA at 25°C but by added iiapurities. PVC contains a built-in trap in the polymer
chain at the C-Cl group. The electron trap in commercial
PMA(Luoite) is benzol peroxide or another chemical
\
,
\-
initiator. Electron Traps were also internally generated1
in pure P M A polymer by radiation followed by heating
up to 120°C.
I
••
•••
'
47225
(AWRE-O-31/72) SOME MEASUREMENTS OF THE
ELECTRICAL CONDUCTIVITY INDUCED IN POLYMERS BY
PULSED X-RAY IRRADIATION. Barry, J . F.; Culliford, E. R,
(Atomic Weapons Research Establishment, Alderrnaston (England)). May 1972. 22p. Dep. NTIS (U. S. Sales Only). UK
SO pence.
The electrical conductivity induced by pulsed x-ray irradiation
was measured for the materials Mylar, polythene, and PTFE.
Dose rates in the range 10' to 10" rad/sec at x-ray energies up
to 4.5 MeV were used. For a given material, the results exhibit
considerable scatter from sample to sample. This Is attributed to
minor variations in the electrode structure and in the composition
of the materials, their effects being enhanced at the low conductivity levels involved. The results indicate that the conductivity
varies linearly with dose rate, no strong evidence being found for
saturation effects up to the maximum dose rate of 10" rad/ecc.
(auth)
1
^ ^
O O
f
DISCHARGE CHARACTERISTICS OP PHOTOCONBUCTHTG INSULATORS
I.P.Batra, K.K.Kanazawa,H.Seki
J.Appl.Phys. 41,3416(1970)
Discusses a method in •which the floating surface of an
Eulator is oharged up to a voltage V and its subsequent
decay measured upon exposure to|intense light. Knowing the
relation between the instantaneous surface voltage and
the exposure time one oan obtain the value for the
carrier mobility from the theoretical expressions of the
paper.
SPATIAL AND TEMPORAL EVOLUTION OF CHARGE CARRIER DISTRIBUI.
TIO1IS FOLLOWING PULSKD PHOTIHJECTION
I. P. Batra, B. H. Sche ch tman, K. K. Kana aawa
Solid State Communications £,1433(19(0)
Fundamental. Eqs. for charge carrier dynamics in photoconductors without intrinsic conductivity are solved.
Time-dependent spatial distributions of carrier^, field,
and conduction current are obtained and related to the
observable (raeasured)quantities of current and voltage.
„_
oL
S DUU TO PULSE ILLULill.'ATXOi; 117 Tiíiá Pi\EÜEi:CE OF
I . Y. 1 la.tru., H. 'ácki
J.Avpl.Phy s. £1,3409(1970)
'' '
"1
" DISCHARGE CHARACTERISTICS OF PHOTOVOLTAIC INSULATORS
!
]
I.P.Batra,H.Kanazawa>H.Seki
j J.Appl.Phys. 41,3416(1970)
IBM Corp.Res.Lab.,San Jos'e,Calif. 9 5 H 4
The conventional techniques for measurement of mobility
sandwiches has the sample between two electrodes, at least
one of which is transparent.The sample is illuminated
through this surface, the resultant current is measured
under constant voltage.In the present method one surface of
nr
the sample is grounded,the other left floating.The latter
/
is charged to the initial voltage V o and the voltage decay under illumination is measured. The relation between
the voltage V(t) at time t and the exposure time t is the
"photoinduced discharge characteristic" PIDC of the plate.
From this the mobility can be calculated with the aid of
expressions derived in the paper. Measurements on amorphous
Se films deposited on Al substrates are reported.Good
agreement with theory is found. - The method is based on
illumination with a light pulse that must be intenso enough,
to inject all carriers stored on the surface into the bulk 1
in a time much les& than the transit time. Once the carriers
are injected, pulse duration is E H S of no consequence
•
since further injection becomes impossible/ With no
i
electrode required on the illuminated surface, the need for
strictly blocking ohraio contact is eliminated. '
.
SP.1GS-CHM0EE M M ü E E Q CXffiREHIS M.
DIELECJEEia' ST.RUCTÜHES
. B 2^,1592(1970))
Phys.Eev. B 3,3571(1971)
35-
r
Í
1
1
*-->.
f,r,:
!'
|
i
;
i
;
\
CHARGE CARRIER DYNAMICS FOLLOWING PULSED PHOTOINJECTION
I.P.Batra,K.K.Kanazawa,B.H.Schechtman,H.Selci
J.Appl.Phys. 42,1124(1971)
Spatial and temporal behavior of carrier density,fields
and conduction current are calculated for a configuration
in which the free surface of a photoinsulator is charged
to a potential and carrier injection generated by a short
pulse of intense light. Results provide a physical picture
of carrier dynamics and allow a qualitative discussion of
trapping effeots.
PÜLSJ3 INDUCED P1IOTCCUR3Ü5IÍÍS AH» FIELD
III HIOTOOOirDUOIÍDEADlJiJLECÍHlO BTfíÜCTÜRES
I .P «Batra,B.H.Sohéohtroatt
J.Phys.Chem.Solids ^2,769(1971)
The fundamental Eqs. for carrier dynamis are solved for
pulsed injetion,excluding diffusion and trapping, for a
photoconductor sandwiched in between two dielectrics or
one electrode and a dielectric.
37
1
ON THE "CROSS-OVER" EFFECT IN SURFACE POTENTIAL DECAY
I I.P.Batra, K.'K.Kanazawa
Japan. J.Appl.Phys. 31,267(1972)
When polymers,in particular polyethylene, are charged toy
surfaoe charge deposition on a free surface, the slope of
the decay curves increases with increasing value of deposited
charge. Experimentally this has been found to lead to
decay curves for the surface potential, which eventually
cross each other, the "high-charge" curves becoming situated
below the "low charge" curves. It is shown that contrary to
a previous (Wintle) believe theoretical curves assuming
a finite field-independent depth of penetration of the
Bpace charge nor the introduction of a field-dependent mo—
bility,thermally generated carriers,field-dependent inkection
and thermally activated release of the surface charge are
unable to explain the effect. No satisfactory explanation
exists so far for it.
.
1
THE EFFECTS OF 25 MEV BETATRON BREMSSTRAHLUNG AND 14 MEV NEUTRONS
O N THE ELECTRICAL CONDUCTIVITY OF POLYMER DIELECTRICS.
Bozin, A.P.
Fiz. Werdo3o Tela, 4, 2385(1902)
"
Results of measurement* carried out with 5 polymers irradiated .by bremsstrahlung (overage
energy 9.5 MeV) and by neutrons are given. In the bremsstiohlung beam the voiume
resistivity decreases instantaneously by 2 to 3 orders of magnitude, but recovers its
original value after irradiation had ceased. At the energies concerned only Ccrr.pten
effect and pair production ore of importance. Absorption cross sections for carbon at
9.5 MeV for the two processes are related os 4 to 1 , The primary radiaiion effect in
organic dielectric is ionization and excitation of molecules resulting in the clissociation and breakage of chemical bonds with the formation of free radicals. The
secondary effect is lhe interaction of free radicals among themselves or with other
molecules. In some coses these secondary effects are accompanied by ruptures and
contractions of polymeric chains and in other cases by recombination of free radicals end
branching of the initial structure.
!
|
f
j
'
• \
'
!
101Í BiPLA-iTATIOH líííO lilSViXATOílS: CHARGE-ÍÍIÍKÜV/OÍ SíuHIES
U3IIÍ0 lülJ-lHDUOai» CHAiíACTEÍÍlSTlC X-RAYS
U.BeezholdjE.P.Eer Uisse
Appl.Phys.Lett. 2^,592(1572)
A persistent problem in this technique has been charge
buildup on the insulator surface,affecting counting
of implanted ions or actually causing surface damage due
to electrical discharge«Techniques for charge removal
were heating to increase conductivity,use of pulsed ion •
beams,conductive layers or strips applied to the surface.
Authors have studied effectiveness of these methods
for removing charge buildup in l/t0 to 300 keüí proton
implants into insulating substrates by monitoring the
ion-induced characteristic X-rays emitted from the tartfet
ions.The .number of X-rays produced oer incident ion is a
strong function of the energy of the incoming beam.Therefore any Coulomb slowing O E ueflection of the ion beam can
be detected as a change in tho accumulated X-ray yield
per unit ion fluence.Any charging or discharging effects ,
will be revealed by simultaneous changes in X-ray pro duction rate at a fixed ion flurc. It \ras found that
successful implantation *.:as achieved vrhen a thin metal
coating iras applied to the insxtlator surface or if there
vas a conducting mask making good contact with, the implanted
surface. Ion current is Measured fro;.: the film or mask.The
beam should bo defocused to flush the entire sample. A Method of neutralising the positive charge buildup is
presence of a hoj electron-emitting filament near the aurface,uith. siovoral bias voltages applied. X-ray output during
proton bonibardment was bslow normal and always irregular.
So:r.e brensstrahlung X-ray output,sometimes in bursts,••.ias
seen. It was believed to be due to electrical discharge
and attraction of groups of electrons from the filament
to the highly charged insulator.
LQ
F
I
'
!,
'
1
\
1
i
J3FFÜCT3 OP HIGII-ilüIOÜGY RADIATION OK TÍIÍZ lOLE'
PROPI-iiTIiCS 01' yJPOXY RESINS
H.Beinc
Techn5ssc.be Hocbsohuleyllmena.ii,Germany I965 (Thesia)
Reports experiments with 1.5 LleV electron irradiation
6
at 10?ri,a/seo, total doses Letweel 1 0 - 1 0
9
Aí
rad.
After-irradiation oolouringsbreixlcdown,surface effects,
and conductivity were investigated» Samples irradiated
with io" rad are destroyed v/hon they are heated during
irradiation beyond 80°C.Conductivity is decreased "but
after «one days returns to nonaal values. It ic •believed
that irradiation produces lower molecular compounds
which are gradually absorbed,,
'
TABLES OF l/;SaGY LOSSES AND HA!:0L3 Or r.L^G?:-íOUo A2TD
POoITTICKS
I.Í. J .uGT^cr, >"> .'••. Sol taev
ln"0tu'15os' of Penetration of Charged P a r t i c l e s into
;»'attcir';u.Fano ed.,i:&tional Acade-iiiy of Sciences,National
Tíesea^-ch Council,Publication 1133(3964)
t
ft
q
I *~
T".t)lcs aro civen for ybout i\0 materials and So
botween 10 V:eV and 3000 I.'.eV.Tl.ey contain:,7iean er.crry-loss
of elor.tror!? by collision v/it:: a+o'nic electrons cr.d by
3reri3r,lrDVi]unc,ir.oj(V) range,rarliation yield(converaior of
electron Mnetic energy into broosstr&hlunipck3t&SS& efie
Avusillary tables contain information áboilt reatrioteà.
colllsioní-osses in vater, c r i t i c a l energies'(at which còllisibn
sad: íirenss-tra&IuHg losses^ are eq.ual),electron-positron
diff
in regard to energy loss and range.
2ÀBLS3 OP EI-rjüflGY LOSSES Aim aalVGBS OF ELSOTiiOUS AKD
P0S1TH0N3
1ÍASA S P - 3 0 1 2
(1964)
ÁDDITIC1TAL STOPPIHG POTrBR A1ÍD RA3ÍGB TABLES FOH
P2iO'ÍO]fS,:-.3SOi*S,Al:D KLJSJCPfíOUS
'
M.J.Bercer,S.Li.Seltzer
1IASA SF-ÍO36 ( 1 9 6 6 )
A A
* '
CALCuLATIOÍÍ OP TllATíblENT MIOTOCUiÜffilJTS III IHSULATOKü 'WITH
THAiPEl» SPACE CHARGE
A . e
J.Arpl.Phys.44,S ; 26(l973)
T r a n s i t time and piílse shape of phptoinjected c a r r i e r s
moving i n the presence of trapped space charge with
d i f f e r e n t profiles(uniform and. exponentially decreasing from
surface of i n j e c t i o n ) a r e c a l c u l a t e d »
TRA1ÍSI1ÍÜT iffiSlCliSli O'n" COBALT SULF-i'OVJlOUi;]) laJUTKO";
I
II. üoook,k•Stimlcr,0. Stri ndehr.g
liucllnstr. and Methods Q]_i2'j'
a , RAJIATIOIÍ 11ÍDUCIO CONDUCTIVITY TJ POLYSTYRLITE
riTU 1IAHHOU 1..0L3ü\JLiiK 'iflilGH'i? DISl'^IBoilOil
H.B.Boe£jch,A.S.Iiill
it-i
IBD33 Trf.no.ííucl. S e i . iJ3-l_6,lío.ó,124(19óy)
T'
Measurements are reported on thin disk dielectric
film capacitors.Doses rates were 10? toJxlO-'-0
rad/sec, time resolution 5 nsec. A kinetic model
dominated by carrier trapping is used. Vvhen
are rate constants,carrier aensxties,trap densities
for shallow and deep traps, one has *•*{(. bt*f>v*Unifa*
i
'•-
It ie assumed that no ionization occurs from deep
traps.
1
M
r
i
i
4654
SHORT-TERM RADIATION-INDUCED CONDUCTIVITY
IN POLYSTYRENE FILMS WITH NARROW MOLECULAR WEIGHT
DISTRIBUTIONS. Boesch, H. E. Jr.; Hill, A. S. (Harry Diamond Labs., Washington, D. C ) . IEEE (Inst. Elec. Electron. •
Eng.), Trans. Nucl. Sei.; NS-16: No. 6,124-9(Dec 1969).
From Conference on nuclear and space radiation effects; University Park, Pa. (7 Jul 1969).
Thin disk dielectric film capacitors were prepared from a
series of special monodisperse polystyrenes and irradiated in a
flash x-ray facility. Transient conductivity In the films was measured with time resolution «5 ns, for dose rates from 107 to 5 x
1010 rad/sec, and related to a kinetic model dominated by carrier
trapping. Estimates for constants associated with a class of shallow traps were obtained for the assumed model. No significant
molecular weight dependence of the early-time induced conductivity
was found. Molecular weight-dependent departures from second
order decay kinetics were noted, (auth)
/ 3 J?
'
i
RADIATION EFFECTS IK COOTONEIJTS AITO CIRCUITS.
William A. T3ohan (international Business Machines Corp., Owego
II. Y.) 11 p.
(COHP-432-1)
From Radiation Effects Conference, Syracuse, H.Y., June I963.
The effects of/radiation pulses are described for transistors
and capacitors and interpreted in terms of semi-empirical models
These and other effects are then applied to the analysis of
switching circuit 'behavior under a pulse of radiation. Some
basic considerations on component selection and circuit design
practice that v/.ill reduce the sensitivity of circuits to
transient radiation effects are also included. (p.C.H.)
A&
Í
iQUASI FERMI LEVEL ANALYSIS OF RADIATION-INDUCED CONDUCTIVITY ;
.' IR CEHAMIC INSULATORS
C.F.Bohren ,U.V.Davis
5"^
Trims.Araer.Nuclear Soc. 8,,37O(l965)
Irradiation lifts electrons from the valence band into the
conduction band and leaves free holes in the valence band.
The electrons traverse the BX#£±H3CX sample and are scattered
by lattice atoms and/or defects untile they recombine ?/ith
holosfdirectly or via a recombination level in the forbidden
gap. Thus both holes and electrons comtrafeute to the conductivity. A mathematical analysis in terms of Fermi level
shows that the conductivity under irradiation is given
fejr
unirradiated conductivity times exp(v//kT) where is the absolue value of the shift of the Fermi level,Agreement with
experiment for several metal oxides is found.
I
j
THE COKPTOIf EFFECT AMD ABSORPTION OF POWER BY THE
SPACE CHARGE
O.G.BokoVjM.V.Yudovich
Izvestiya Vysshikh Uchebnykh Zavedenii,Fizika
(Bulletin of the Institutions of Higher Education,
Physics) No.9,95(1970)
Kl
'
RADIATION DOSIMETRY BY CURRENT GLOW CURVES IN DIAMOND
D.N.Bose,H.K.Henisch
Solid State Electronics 11_, 273 (1968)
I Dosimetric capabilities of current-glow processes in neutron
I bombarded diamond in the u.v. and visible light regions
are described.The effect of boiabardinent on the spectral
characteristics of excitation and infrared quenching has been
studied. On that basis a self-consistent model for the trap
distribution before and after bombardment is formulated.
r,
° L
r~
j
I
**-
\
j
I
|
|
PYROELECTRIC DETECTION OP X- $AY ABSORPTION BY
TOURMALINS
D. N. Bone, J . IvI. Henisoh
S o l i d S t a t e E l e c t r o n i c s (GB) 1£, No.2,65 0-969)
P y r o e l e c t r i c p r o p e r t i e s of t o u r m a J i n e may be used f o r
measurement of l a r g e X-ray closes.The p y r o e l e o t r i c v o l t a j
a c r o s s a specimen s u b j e c t e d t o uniform h e a t i n g between
300 t o 600°K goes t h r o u g h a maximum which i s dependent
upon t h e p r e v i o u s l y r e c e i v e d X-ray d o s e . T h i s b e h a v i o r
i s correlated with thermally stimulated current
measurements.Sensitivity i s low,but storage capacity
i s high, of the order of XÍ5X io5 raâx R.At roora
temperature energy does not decay measurably over a
period of tiro weeks. - The decroaoe of pyroelectric voltage
is due to thermal generation oi' free charge carriers.
X-raya have the effect of exciting such carriers into
traps, fron which they can be released later "by
heating.
IÍOISE SXGKALS ,.ND CARRIER KOUULATICIS AKISIKG III LA.-JCa'u
CABLES DUiillTO IJUCI^AU PUI.SU I RADIATION
K.Bothj ll.P.Brue.mruor, C, E. Lasca.ro, J.3iev/berc';/.Schloo3«r
1BEB International ConvontiOn,líow York,March 1963 ,
COliF-58-3
Effects were measured as a function of vo] tage and
iiiEtHxy treatment history of sample. Strong memory effects
were observed»
754
(BNWL-SA-1658) HADIATIOH INDUCED CURRENTS IN CABLES. Bourassa, Ronald R.; Stringer, James L.!
Dau, Gary J. (Battelle-Northwest, Richland, Wash. Pacific
Northwest Lab.). Feb. 7, 1968. Contract AT(45-l)-1830. 5p.
(CONF-680601-38). Dep. CFST1.
From 14th Annual Meeting of the American Nuclear Society.
Toronto, Ontario.
l h e problem of currents induced in a coaxial cable was studied.
An equation is given for the currents from gamma-ray absorption
by photoelectric and Compton processes. Experiments were c a r ried ou< ;n a st Co gamma source and a TRIGA reactor. The current was negative and proportional to the dose rate in the gamma
source, while both negative and positive currents were induced
in the reactor. The bulk conductivity of the MgO Insulator was
also measured. (D.L.C.)
v~/
\
1
•
/
0.1 IE EPFEC'T QV SPACE CHARGE OIT THE TRANSMISSION OP
CAl'jiOi/:-; iiAYS THROUGH THIN IJÍSULATIHG F I L k S
C.Bovrlt
Bri t. J. Appl .Phys. 18,15 B5 (1567)
The energy distribution of cathode rays transmitted
through thin dielectric films changes during 'bombardment.
i.ociKurciaoivbEi of this effect arc reported and are inter prctod in terna of an accumulation, of space charge.
Electron beam energies were of 30,35, a-nd 40 keV. Dielectric
(absorbing) films? ".fere uoed of ASgS. sandwiched bet-.reen
thin &old elocti'odec (~5000A°).
A suppressor voltage
was used to royu'J no socondary electrons and a retarding
volta;;e allovred to measure the enerj; spectruia of the
transmitted olecteons recorded by means of a Paraday cup.x
Considerable time effects -.jcre observed.- It must also
be noted tSiat even in thin films of insulator completely
penetrated by cathode rays, sufficient space charge can
accumulate to affect the transmitted electrons.
THE THRilSHOLD EUERGY III THIS ELECTRON BOiiBAHDUKMT CO1IÜÜCTIVITY
OP m-ãhEWKLC FILMS
J.Phys.C,Solid State Phys. £,159(1969)
Cathode rays induce steady state conductivity ib an amHfiirpkocKa orphous film only if their energy exceeds a
threshold.A comparison betv/een threshold values and
theoretical data for the differential energy dissipation
of fast electrons in solids shows that^'the threshold valie
the electrons penetrate only half the film thickness.
The space charge which develops under these conditions and
v/hich i s made responsible for the occurrence of the thresh»
threshold, i s studied by experiments i n which both sides
of self-supporting
films of arsenic trisulphide are
exposed to cathode rays.
í
ABSOLUTE YIELDS OF X-RAY INDUCED PHOTOEi-lISSIOH FROM
METALS
J.1Í. Bradford
IEEE T r a n s a c t i o n s N u c l . S c i . ITS-lj), 167(1972) ,V°S
Absolute e l e c t r o n y i e l d s from tantalum,molybdenum,copper
and aluminum have been measured f o r g e n e r a l X-ray bomb a r d i n g g e o m e t r i e s . Photo s p e c t r a used were d e r i v e from
f i l t e r e d bremsstrahlung generated i n a tungsten
anode
a t 50 ks3£ kV, c o n s t a n t p o t e n t i a l .
INDUCED CONDUCTIVITY IN PRK-IRRADIAT3D INSULATING MATERIALS.
Bradloy, A., Pinkerton, A.P. and Grand, S. Radiation Research
Corp., New York. In PAPER 3 Of FOURTH RADIATION EFFECTS SYMPOSI
UM, 15-16 SEPTEMBER, 1959» CINCINNATI, OHIO. C3KERAL SESSION
PAPERS 24pMeasurements of induced conductivity were made on samples of
boron nitride, quarta, mica compositions, polystyrene, and
glass which were electron irradiated at 10^ rads/hr. Natural
mica and Corning 1?23 borosilicate glass exhibited the lowest
induced conductivities of the materials tested.
AE—455
LONG-TERM TEST OF SELF-POWERED NEUTRON DETECTORS ... Brakes,M.j ct. al. Aktiebolaget
Atomenergi, Nykoepmg (Sweden). 1972.
& 0
BFFBQTS OF ELECTRON IRRADIATION ON TH3 ELECTRICAL PROPERTIES
OF KYLAR
Power Apparatus and Systems,February 1958>P^1539
E.L.Brancato,J.G.Allard
Field strength r? polyethylene tstxs. terephthalate is
found .
.to be sensitive to radiation.After irradaiing
a 5 x 10"^ cm sample with 10 rad of 2 MeV electrons,at
a dose rate of 10°rad/min,breakdown field is decreased
by
f :
EVALUATIOW OF TKE COMPTOlf CUR8EWTS FROH A 1 4
SOURCE IN THE INTERMEDIATE ALTITÜpr tlhüSS
HEV UEJTMtí
J.Ercol&J.Celiiih,R.i).Schambeyíey
Tra«satiions AKS ]^3,e56(í970),
Encrcy. deposition, r a t i o oi polar to r a d i a l cor.iponeàt
are mM£ciiLcEa:eior Coinpton currents duo to the seconda.ry
photons, for source a l t i t u d e s up to 50 k f e e t .
[
,
©Z
\
f
TIME MIT) 'J'i&PEUATURE DKPMroBITCH OP IRRADIATION EFFECTS IN
IW SOLID DIELECTBD CS
R.G.Brown
E.I.du Pont de lieymovrs
Bull.An.Phys.Soc. 3 2.27^(1967)
Decay oi1 elfictron âirtrj.Tvjtion ín.iocted i n t o polynerr:
were Ajiypsti fatod f o r 2 MoV e!l pctrons.Ureakdcvm and' ssVrtiTnrrjfw
choree r e l e a s e wore t r i p ^ e r e d by a p-rounded probo. The -decrease of ohnrge with timofat constant ternrerature) wars i n tcrTreted in terna of voDun:e reíaistanc-f!. For poilypethylr^ethacrylat** and polynroT>yü fne r e s j stnn^e v ? ] " " s a t r o w tor.—
peratiiTp a r e of t h e same order f o r i r r a d i a t e d and n o n - i r r a diatod i>\?/bari'i s. whilo for •no.lyfcsyreno a liir^e chp^r-o of
resj.rtj.vity i s observed.Activation ener"7f!S or tra^o ciepthr
estimated from temperatu^e dependence wen about o.6 eV
for the two first-named niaterj.aü s and 0-4 oV for -rolynro^
pylene.These values are lower tr.pjn those inferred fron
steadyntate conductance, with no i r r a d i a t i o n . Carrier creation
by injection may reduce the obsc-rved activation ener.^y to
that characteristic of n o b i l i t y .
ç
TlkS A3JD TEI.^EíaTmffl D3PElTIi3írüa OF lifflADlATlOH Ebi'ECl'S
"
IN SOLID DIELECTRICS
R.G.Broim
J.Appl.l-hys. 38,3504(1967)
Decay of electron diatribution injected into a polymer
solid at 2 l.oV was investigated by measuring the charge
released in a triggered discharge. Fron the decay time the
volume resistance was calculated.For PcuLyinsthyl&eliacrylate
the temperatura variation of the resistcne gave an
activation energy or trap depth of 0.6 eV.Discharge
figures were also produced in polystyrene and polypropylene.
trap depths being respectively 0.6 and 0.4 eV.
I01ÍIC THBKlOCOiroUCTIVlTY.KETJÍOD POR THE I1TVESTIGATX01!
OP POLABIZATIOir III INSULATORS
C.BuccijR.Fieschi
Phys.Rev.Letters ^2,l6(l96 r 4)
Describes t h e method, f o r i n v e s t i g a t i n g thermal
r e l e a s e of i o n i c movement.
I01IIC THBRl-lOCURREHTS III DIELECTRICS
O.Bucci,R.Fieschi,G.Guidi
Phys.Rev. 148,816(1966)
Thermally activated release of dielectric polarization is
stiidied in detail-for alkali halides.The theory for
nonomoleculur kinetics is developed and applied for
interpretatior. of activation energies.
li 3
Lh
l
b
B S~
'SKA!: yiAür.
Vi.H.Luel.alow,L.I).Pose;/
SC-iüí-6^-512 jlicy.jua.ndia Labs.,October 1Ç6S
'
liadiation Source Id. agnostics jvivisioii ;3223
'
Methods; ior pcrfor:,;int' pulsed electron beam diagnostics
arc presented and tochnicuerj for deteri:.i:ii:i£; energy
deposition profiles and beai.: enorQ' densit;.1 are uiscussed.
'I'ecimi^uoij for the liütüiv.iüjition of electron beau pulse
profile and differential energy spectnu.i are conui úored.
üatu roiVr to the Sandia Model 705 i'ebefcroviand ";ier.:.oc 1.
.
i
!
;
;
j
,
j
|
1
14432
DIELECTRIC PROPERTIES OF A y-IRRADIATED KDP
CRYSTAL. Burdantna, N. A.i Kamyshova, L. N.; Zhukov, O. K.
(Voronezh State Univ., USSR). Sov. Phys.-Cryst. <Engl. Transi.);
15: 721-2(Jan-Feb 1971).
Translated from Krlstallografiya; 15: 834-G(July-Aug 1970).
The effects of small y doses up to 982 R on the dielectric constant and losses of KH2PO4 crystals were studied. The tempcrature dependence of the constant shows an increase at and below
the Curie point. The initial maximum in the losses decreases and
a second maximum at -1G5°C appears whose magnitude decreases
somewhat with dose. The changes are stable with time. It is suggosted that irradiation reduces the mobility of the domain walls.
(D.L.C.)
LOW u:il&G"i" 13LECTRCII Bi-.ISSIOIT F-P.0K kSTALS
L.A.:2url;e, J.À. Jall,A.H.Pr3dericl:son *
I3E2 Transactions :iucl.Soi. I?S-17>193(l£7O) Ar'6
(Air Porco Ca;..brid£e iíesoarch Laboratories,L.Cí.Hcnsoi;. ?iel-d,
Bedford,LIA 01730) UóA
_,
lovr eiieVuZ electron emission fror. several notais exposed to
Co^° gai.ii.ias,10 LleV electrons, and 0.1 to 1.0 keV electrons
has been studied.lixporiiaonts described here,together -.ritii other
results,indicate that ioor a given metal the emission of electror
with energies up to 50eV is proportional to the absorbed
âose,ináopenuently of t;pe and energy.' of the prinary radiation«l;'or coi.imon metals one gets about 1 — 3 xl0~
coul/rad.
The magnitude of tho emission due to high e n e r ^ radiations
can be predicted frou the ± E sccondar;- emission yield observed
under low electron e n o r ^ boubardraent.iiata seew to be consistcni.
vith. internal isotropic loi-r ener^ electron distribution
íjiven b;. íris) ~E"' .. Investigation was undertaken in vievr of
the importance these er.iission x;rocessea have for a auuber of
radiation effects in solids, such as replacement currents,cpaca-
I
,-,
# '
charge buildup in dá electrics,and generation of transienjt \
electromagnetic fields. Secondary emission can also be J
a source of troublesome noise in experimental studies of
radiation effects. Currents produced by these low-energy
electrons are essentially a sensitivive function of
relatively low differences between components.
L&
'
PHOTOGRAPHIC REGISTRATION OP ffiRANSIENT
RADIATION ON A DIELECTRIC
I.Cabak
Czech.J.Phys.B. 19,no.1,96(1969)
(Pao.S.ci.Palacky Univ. ,01omouc,Czechoslovakia
/
/
An experimental proof of the existence of transiant
radiation originating at electron transience from
vacuum into a dielectric is given.The radiation
originating at the passage of the electron into a
FVC cylinder was registered on a photographic emulsion
6850
X-RAY AND GAMMA INTENSITY MEASUREMENT.
Cabe, Leslie E. (Western Electric Co., Whippany, N. Y.).
IEEE (Inst. Elec. Electron, ling.), Trans. Nucl. Sei.; NS-16:
No. 4, 29-30(Aug 1969).
A method for developing a graph of radiation intensity vs. time
for a pulso of x-ray or gamma radiation is presented. The method
has been used for determining radiation intensities from pulses
of nanoseconds duration with intensities in the 10" to 10" roentgens/sec range. It Is applicable to pulses of different durations
and intensities, (auth)
_- .
/ /
I
Si'ABB CHARGE IN PLASTICS BT L07/ EÍ7E3GY EL3CT30ÍI3 (Revised)
V.J.Caldecourt
Report,Dow Chern.Ind, 9-29-65
fl
Space charges are introduced by injection of low energy electrons(below 1 k e V ) , This is done by plasma formed by a corona
point above sample and reaching through a screen in front of it
. a-Conductivity measurements give a current which decreases with
time, Final current is a function of voltage applied. Conductivity in a vacuum is about the same as in a gas, Therefore
it is due to charge carriers present in the polyner, b- 21ectr<
static field measurements were made with a rotating probe and
: induction plate system.Charge decay curves are measured arid a
• charge storage effect is found, c- Net charge v/as measured
j with a Faraday cage system. They indicate a positive charge
| layer at the bottom of the film attributed to holes left
by electrons emitted from the bottom surface into ground.
j
1
I
5065
SPACE CHARGE IN PLASTICS BY LOW ENERGY
ELECTRONS. V.J.Caldecourt.
.
Electrical Insulation, Duck Hill Falls, Pennsylvania, 1965 (WashingIon: National Academy of Sciences.National Research Council.
lÜGO),pp. 9-11.
The space charge results from the ability of many plastics to I •
trap electrons. A direct Indication of the presence of space charge!
was obtained by recording the electric field strength. A film of the!
sample was charged using a corona point and screen device and I
then rotated under a field Btrcngth meter. The latter was a small
vluratlng-vane version of a generating type electrostatic voltmeter.
The film was recharged several times and the decay was plotted
on a log-log paper. The results for polystyrene are discussed.
R. N. Dasu
<_o
/ i
DEEKCTOÜ . HANDBOOK
'
I UCKL-5O176 (Cal.Un.Iivermore Rad.Lab. August 1967
j
(Contract W-7045-eng-48, 150> P .Eep CFSTI
Discusses photodiode linearity^,
.
, and
saturation data,calibration techniques,fluors and
radiators,test ligth systems, logarithmic detectors,
Gompton detectors, photomultiplier detectors,photodiode
detectors,solid state d etectors»
' '
G.l.Car.o
I
50548
(N-70-20649) RUGGEDIZED GAMMA RADIATION
DETKCTOK. Fina'Report. Carrell, T. E. (North American
Rockwell Corp., Los Angeles, Calif,). 23 Sep 1969. Contract
NAS8-20B4D). 74p. (NASA-CR-102509; NA-69-609), CFSTI.
A description oi the design, fabrication, and testing effort conducted to provide a prototype gamma radiation detector capable
of operating in the severe environment that will be encountered
In the vicinity of a nuclear powered rocket engine is presented.
The detector is based on currents produced by C<~ npton scattering in a dielectric material. The lecluiical discussion centers
on the theory of detector operation, specific details of fabrication and the results of performance qualification testing. The
ruggedized gamma radiation detector is designed to measure
gamma radiation intensities in the range of 100,000 to 10 to the
7th power roentgens/'iour in a space, ambient and liquid helium
environment. It is a sWf powered device that is capable of operating in a high neutron field, and under extreme conditions of
shock and vibration. The three prototype detectors developed
have successfully demonstrated compliance with all of the
technical requirements, (auth) (USGRDU)
I Iff
THE COkPUTATIOi: OF PH0T01T RADIATIOII IITDUCSD ELSCTROir
t'
EiHSSICIT
f
VT.L.Chadsey,I.Kohlberg
,
IEEE transactions Hucl.Sci. HS l8_,ITo.6(150(1971)
.
Describes simple analytical models to determine the
transport of charge due to "Photo Coiapton Currents".
The model is one-dimensional and predicts the relative magnitudes of the photoelectron,Compton,Auger, and secondary
electron
contributions to the emission current. Theoretical
results are compared with theory.
v
_
•-
"
""
" ~
" •
TT-y
j
•
>
•
;
;
j
!'
1
I
I
TRAPPING OP ENERGETIC ELECTRONS IN SOLID DIELECTRICS
Vita .V/. Chang
,
B.S.Thesis,Ii.I.T.(l963)
j
RADIATION CHEMISTRY OF POLYMERIC SYSTEMS.
Chapiro, A .
New York, Interscience, 19Ó2. 712 p.
..
'
A chapter "General aspects of radiation effects in solid polymers" contains a survey and
bibliography on radiation-induced conductivity and on spark discharges in irradiated
plastics.
ST'.ICON J3VÍLÜT01Í j.K.tfllieíJCTa Oi'1 K^IÍCY Jia-OS
IIT ALUiiliPJi.: ÍTi i . O I l C K T ^ i f t l C Hi.iiCi'HOJS
SSC;1fppllJG.]hi!:!V.lirc;i'í3
.
o i . IT3-IT_,272(1970)
Ti-IE DOSE R/LTE RESPONSE OP A UYE-POLYCHLOROSTYREITE
FILM DOSIMETER
S.E.Chappell,J.O.Hu»phreys
IEEE Transactions N u c l . S o i . 1IS-19., 175(1972)
Measurements performed
. at low (llV r a d / s e c ) e,nd
high (10-^5 rad/aec) dose r a t e s showed no influence of
the dose r a t e .
ft)
|
DISSIPATION ITEAR All IITTEPJACEs^iOriB iraALJU'TIC
APPROACH TO ELECj'llOir BAITGE AlíD STOPPING POs/Elí
D. U • Ciliar i ton
Riid.HoB. 44,575(1970)
E:TERC!Y
0%,
Buli .Araer.Ph.yG. Soo. II,Vol.l7_,llo.l,p.115(1972)
HL 16 Space-Charqe-Perturbed Photo-induced
Discharge of Photoconductors. I. CHEN. J. MQRT and
R. L. EMERALD, Xerox Rochester Corporate Research
Center. Rochester. N.Y. ~ The photoinduced discharca of a photoconductor 1n the non-constant voltage
mode has been studied theoretically and experimentally.
The surface potential after the onset of illumination
1s calculated by an Iterative method. Different
modes of illumination, I.e. instantaneous flash,
finite duration and continuous exposure, with
strongly absorbed or penetrating light, have been
considered. The effects of various electronic properties of the photoconductors such as carrier emission
efficiency and carrier mobility and their field dependence, have been investigated. On illumination with
strongly absorbed light, the discharge of a photoconductor with low carrier mobility (<10"5cm'/V-sec)
can be space-charge-perturbed
at moderate light
intensity (V10 14 photons/cm2-sec). If the mobility
is field dependent, the perturbation is even more
severe, and leads to high residual potential. Many of
these theoretical predictions are confirmed with
experiments on Poly(N-vinyl carbazole) sensitized
with amorphous Se.
i
I
o .,
Oá
'
fir**"'"
|
.
I
i
[..
;
i
! :
!
18558
EFFECT OF PROTON BOMBARDMENT ON THE
CONDUCTIVITY O F ALKALI HALIDE CRYSTALS.
V.A.Chernyshev.
Izv. Akad. Nauk SSSR, Ser. Fiz., Vol. 29, No. 1, 71-4 (Jan. 1965). In
Russian. English translation in: Bull. Acad.Sci. USSR, Phys. Ser.
* (USA), Vol. 29, No. 1, 71-4 (Jan. 1965; publ. 1966).
^
Irradiation with 4. 3 McV protons resulted in reduction of the
electrical conductivity of KC1 and KI crystals and gave rise to a
break in the linear variation of log a with the reciprocal tempera- /
ture 1/T. In contrast, irradiation of KBr crystals with the same I
doses of (. 3 MeV protons resulted in increase of the conductivity
I in the temperature range from 20 to 70° and a small decrease of the
I conductivity in the temperature range from 70 to 140°C. The values
I of the activation energy in KC1, KBr and KI crystals, estimated from
the slopes of the log a versus 1/T plots, with increase of the radiation dose changed differently in different temperature ranges: in the
temperature range up to the point of the break in the log a versus
1/T plot the activation energy is reduced, while at temperatures
f above the break point it increases and, in fact, becomes greater than,
the activation energy in unirradiated crystals. In the series KC1- ;*
KBr-Kt the peak in the temperature dependences of o U n/°irrad
shifts to the side of higher temperatures. For each type of crystal,
* however, the peak shifts to the side of lower temperatures with in- \
crease of the radiation dose.
I
^~ -••
„
c H
'
55101
EXPERIMENTAL STUDY OF GAMMA-IRRADIATION
EFFECT ON KMiCTKlCAl. PHOl'ERTIES OF B-TYPE INSULATOR. Cliuii, IIco Yuung; Sung, Young Kwrai; Lee, Duck Chool.
J. Korean lust. Elec. Eng.j 18: No. 2, 15-20(1969).
Mica wns selected as typical of tho B-tyiio insulators. Dc, ae, .•
and impulso voltage was applied to the "y-ray-in'adlatcd samples
after constant-time doses and tiino-vaiiuble doses. The dielectric
breakdown voltage and dielectric constant were measured; it was
found that the dielectric breakdown voltage variations arc relatively large, but the dielectric constants are almost constant. The
above result is useful for the selection and application of the inorganic insulators under irradiation, and it is expected that the result can apply to not only B-type insulators but also inorp.anic insulators. (TSS) (Korean Sci. Ahstr.)
3113
EFFECTS OP IONIZING HADIAT1ONS ON DIELECTRIC
MATF.RIALS. Coelho, H. (Centre National de la Kecherche
Scientlfique, Paris). Ilev. Gen. Elee.: 80: No. 7-8. C01-12(JulAug 1971). (In French).
The various work undertaken on behalf of the Ministcre du Developpcment Industriei et Scicnttfiquc during the last ten years is
examined. The most important problems are defined, and tho
processes involved in interactions liotwcen radiations and insulnting materials are discussed in tli« framework of recent
theories. The principal results oMained at this L.C.l.E. are
reviewed, and the idea of associating them with a damage criterion is Considered. The opportunity for studying certain
fundamental processos not yet well understood is examined.
Certain recent, very interesting, results on radiation-excited
currents are discussed; these results have led to the proposal
of certain new research projects. (France)
/
g
A_PAHA1.3H?RIC STUDY OP DIRECT HUCLEAR ELECÍSOGET^HÀTOR CKL1S
USING A BETA KITTING SOUaCB
A.J.Cohen, C.A.Low
New York,American Institute of Aeronautics and Astronáutica,
1963,Pré-print 63048B (üOUF-10-57)
Prom Electric Propulsion Conference,Colorado Springs,Colo.
March 11-13,1963.
2TASA-TH~l>-eO7O (1963)
Reports a design analysis for cells using Ce ^ as a beta
emitter. Factors to be considered are the particle energy
spectrum,energy losses in the fuel and the support foil,
and the relativistic motion of the particles in the electric
field, GsHDiEiiiKaixfaatsass Constructional £xE±sasxükE '
and geometrical factors must also be considered,*Analytical
methods ^are described which give operational characteristics
including weight to power ratio, load characteristics, etc.
11.0. CohG n, R. I). Schar.5b error
ETC 5194,June 1Ç63
Hoad,
L
v
A. M3TH0P O? IKCR3ASIHC TIlü! BL3CTMCAL RESISTIVITY OP INSULATORS
UKOElí IONIZIKG RADI-VTIÜK.
J.H. Onleman and D.B^hm. Journal of Applied Physics v.24,
no.4, p . 497-49S, Apr 1953.
•
Results indicate that high insulation r e s i s t a n c e can be
maintained under radiation i f the inaulator has been previously
irradiated with a sufficient dose.
ELECT1ÍICAL CONDUCTIVITY Hi ALKALI HALIISS I1IDUCKD VY ELECTED"
ECTED"
7iQ] 3Mü'HÍT
P.B..CollÍ!i;:,s,õ'.3Iirüch
.WiyB. 1 ^ 7 9 7 ( 1 9 6 4 )
/
s aro rc; ortod for microcrystalline layers
of several alliali halideo,Current caius varied,no primary
voltage threshold for the effect being found.Saturation
of the current was found in aomo cases.
! RADIATION EFFECTS OH DIELECTRIC MATERIALS
(Final Rep.)
'
I J.F.Colvell, D.W.deKichele,R.F.Overmeyer
ECOK-O1412-F (Report General Dynamic» Co.,San Diego,Calif.)
AD 64.';535
A detailed description of the techniques and equipment
employed in the ion-implantation process is presented.
Results of high-energy electron irradiation of a Mylar
capacitor with ion-implanted electroaeo are compared vãth
the response of a control sample. The ion-implanted
electrodes exhibit better carrier injection than conventional
foil electrodes. Transient radiation effects data from
irradiation of a monolithic ceramic capacitor are included.
The transient radiation effects in Kylar versus temperature
appear to fit a band model for the conduction process in
which the forbidden zone and one sign of carriers is imnio—
bilized. An examination of the energy loss process of noderately fast electrons in insulators indicates that from 1.5
to 3 eV the loss is primarily to excitons vrhereas energy
loss to optical and acoustical phonons occiu%s down to ±2B
thcrios.1 energies»
5
RADIATION-IÍIDUCSD CONDUCTIVITY IK PLASTIC ITLMS AT HIGH
1
DOSE RATES
D.M.èompton,G.T.Cheney,R.A.Poll
J.Appl.Phys.36,2434(1965)
Reports a study on mylar films with K X 30 KeV electron pulses
frora a linear accelerator.Since polarization is not observed
conduction is assumed to be electronic. Conduction is a bulk
effect, an instantaneous and a delayed component are observed.
The first increases as the 0.8 power of dose rate,being independent of pulse width;the second increases more slowly
with dose rate and saturates at about 1 0 l 0 rad(mylar)/sec.
Conductivity increases with temperature EacBi from 100 to 300°K,
It is assumed that EH.carriers of one sign are permanently
and rapidly trapped^'oarSiers of the other sign r s a n a á f
eventually recombine. Saturation of delayed component indicates
existence of a finite number of traps.
a
HO
7/
j
L
i
V""'
[
i
i
:
j.
j ,
j
dAIüÊA INDUCED PHOTOCONDUCTIVITY _ •
III A POLYETHYLENE TERKPHTHALATS CAPAtEITOR
E C d S l I M
Diamond Ordnanoo Fuse Laboratory Report TR-1037(l962)
|
I
TRANSIENT RADIATION EJECTS IS ELECTRONICS
L.u.Coni-ad
InsAdvanoss i nJ Nuclear Science and i'echnolo^v Vol ^
N.Y.Academic l rese
ress (I9b6),
p.144
6ji.'wx.j
( l % 6 ) , p.
144
Effects of neutrons,gammas and ele ctrons in the
energy range from 0.25 eV to 10 MeV*are discussed.
Only xonization rhenoraena which a l t e r the properties
of electronic
in
a
e e components
nn metal
m e t are
a l con
i nBidered,but both dose
íí
? S°,
^ sulators,Bemiconductors
and
S í í íaro
í "included,particular
?*S
^ attention
s u l tbeing
i
given
to radiation effects on insulators.
u
36305
DIELECTRICS WITH PREDICTABLE RADIATION
RESPONSE. Conrad, Edward E. (Harry Diamond Labs.,
Washington, D. C ) . pp 21-4 of 1969 Annual Report. Conference
on Electrical Insulation and Dielectric Phenomena, Buck Hill Falls,
Pennsylvania, October 20-22, 1969. Washington, D. C ; National
Academy of Sciences (1970).
See CONF-691042.
A review on radiation response in organic dielectrics concluded
that the observation of highly mobile short-lived carriers in liquid
organic dielectrics is now possible. Furthermore tho capability
exists to vary the free carrier lifetime by the removal or introduction of a specific impurity. The proved feasibility of theso
techniques constitutes a major step toward a better understanding
of radioinduced conductance in organic dielectrics. (P.C.H.)
L
COHPTOK'-DIODE DSV2ÍQPM2IÍ1! -PRÔÇHAM* -- - < • — - « —
M.:i. Conrad
SC-TM-72 0206
•
(Rep.Sandia Co., to be published
Or
'
il
THE MOD I I I FAMILY OF PRODUCTION COMPTON
a^
DIODES
77
M.M.Conrad
SC-TM 72 0217 (Rep.Sandia C o r p . , t o be publish
ed
CHARGE DISTRIBUTION AND RANGES OF HIGH-ENERGY ELECTRONS IN
LIGfll" MATERIALS
R.D.Cooper,1.'/. Alexander, A.Brynjolfsson
Bull.Am .Phys.Soc. 2,No.l ,103(1964)
U.S.Anny Natick Laboratories
Measurements are reported for water,oil, and Al irradiated
with monoenergetio electrons between 4 and 25 KeV. Near the
beam entrance point charge is removed and driven deeper into
the material,leaving a net positive charge near the surface.The peak of the charge distribution is at a depth
of 0.4 g/cra for energies above 10 KeV and utsmESdiH* at
a lower depth for lower energies. Integration of the
f distribution curves gave charge transmission curves.
TRANSIENT PHOTOCONDUCTIVITY OF POLYSTYRENE AND POLYISOBUTYLENE
EXPOSED TO PULSES OF NEUTRON AND GAI&ÍA RADIATION .
F.N.COPPAGE
PAPER CP 62-1238,I&EE Summer lieeting,Denver,June 19°2
\
.
TEMPERATURE DEPENDENCE OF PHOTOCONDUCTIVITY INDUCED IN
POLYSTYRENE BY TRANSIENT RADIATION
F.N.Coppage,F.C.Peterson
(Sandia Corp.,Albuquerque,N.Hex.)July 1964,Contract AT(29-l)-73Q
(CONF-617-3)
Special Technical Conference on Nu&lear Radiation Effects,
Seattle,July 1964
Results substantiate existence of internal field resulting from
jrrapped space charge and reaching saturation af small doses
(~20 rad at -80°C).Saturation dose increases v/ith temperature.
The spaxje charge sesults from migration of carriers v/ith
subsequent trapping at metastable states^.
,„
^ 100
26
SOME PROPERTIES OP CONDUCTIVITY INDUCED IN POLYSTYRENE
BY PULSiiD GAMMA RAYS
P.U.Coppage, P.O.Peterson
Sandia Corp.Albuquerque,N.Uex. July I965.Contract AT(?9-i}
-789.CCOHP-65O7O7-6)
From IESE Annual Conference on Nuclear and Space Radiation
Effects,Ann Arbor,Kich.)
Measurements with pulsed radiation avoids space charge and
polarization effects. Both the instantaneous current(during
irradiation) and the long-lived photoourrent are observed.The
I
|
latter depends on temperature,its time dependence corresponding
to a bi-molecular reaction. This is shown by l/current versus
time being a straight line. Results permit to determine
conductivity parameters,including no and dirft mobility of
carriers,average distance travelled, and average energy to
create a carrier,the latter being of the order of i®§ 105 eV.
The Efesrga current integral of the long-lived component increases linearly with voltage,thus showing that carriers
drift over distances which are only a small fraction of the
inter-olectrode distance.The temperature effect permits
to determine a well-defined activation energy of 0.2 to 0.3 eV.
/
Tiie long-lived component is attributed to a thermally
activated drift mobility.
i -"
,
,
'
L.
\
v •'
PHOTOCONDUCTIVITY PROCüSSSS III LO.V MOBILITY OUG/uJIC i'.ATl^IALS
F.Ií.Coppage, It. G.Kepler
;
(
IEEE Transactions on lluclear Science Wã-JJj,121{1966) hf'6
Measurements on high purity anth-acene crystals are reported.
In such samples lifetimes of electrons and holes are in the
1 msec range,Thus the number of carriers produced can be
obtained by sweeping them out of the sample with a sufficiently
high field,j^T^/d 1 and measuring the externally collected
charge. It is found that a?-out 3 000 V are neded to produce one external carrier pair, xith samples under 600 keV
X-radiaticn.The high energy, or lov/ yield, is caused
due to rEEzxfciEstism "preferential" recombination,i.e.
an electron-hole pair once created does not apir-àr as free
carriers unless they are created in such a 7/ay t- at they
become separated by a nlinimum distance r v/hich is '.he distance
at which the thermal kinetic energy of the electron (3/2 kT)
is equal to the potential energy of She electron in the Coulorr/b
field of the hole. Applications are also made to polystyrene
•vhoso- cheinical cenponition is identical with that of ar.thracene.
'If)?
'v*»
V
\
j
U
,
I
j
!
|,
EVALUATION OF TUB EFFECTS OF TRANSIENT RADIATION ON '~~
:
CAPACITORS
.
. . . . . . ........ _...,._.,..
.
y.N.Còppáge"
San^^a . C ^ ^ ^ ^ ^ ^ u ^ ^ ç N^Jexico.Contract AT (29)-789
Increased leakage current results from creation of
charge carriers within the irradiated material. The
prompt current component is coincident with the incident
radiationithe delayed or long-lived component persists following radiation exposure.Both components
were characterized for some materials as functions of
temperature ,for pulsed radiation. Gamma radiation is
more effective in current production than neutrons.
An RC time constant is more descriptive of the effect
and figure of merit of materials than c.urrent in-v»
tensity or dielectric loss angle.
I
I
27393
(TID-18343) NEUTRON EFFECTIVENESS IX
PRODUCING PHOTOCONDUCTIVITY IN DIELECTRIC J
MATERIAL. F, N. Coppsge and A. W. Snyder (Sandia j
Cârp., Albuquerque, N. Ilex.). June 1963. Contract ATI
(23-D-7S9. IEEE Paper No. CP-63-1118. 20p. (SCDC"
3115)
Measurements of photoconductivity in several organic
dielectrics irradiated with neutrons and gamma rays reveal that neutrons, relative to gamma rays, are less effective, per unit absorbed-dose rate, in causing photoeonduction. Photoconductivities of polystyrene, polyisobutylene,
Mylar, H-film, reconstituted mica, cellulose acetate, and
polycarbonate were measured during exposures in the
Sandia Pulsed Reactor. The ratio (n/f) of the neutron
absorbed-doso rate (n) to the gamma-ray absorbed-dose
rate (y) was varied with preferential shielding to separate
the components of photoconduction arising respectively
from neutrons and gamma rays. The empirical equation,
a = Ati* + AjVs, was found to fit the data of the measured
photoconductivity (a), where AD, Ay, and 5 are empirical
constants characteristic of a dielectric material. The
ratio, An/Ay, is a measure of the effectiveness of neutrons,
relative to gamma rays, in producing photoconduction arj!
for tie materials studied 0.06 == (Ao/Ay) = O.SS. The rafio,
AaA*. for two samples of the same dielectric type conJ
tain^dt in capacitors of two manufacturers was observe^
to differ by as much as a factor of two. The origin of the
difference was not determined, (auth)
V
103
f
0
•
.
USEFUL TECHNIQUES FOR ANALYZING CAPACITOR TEAiíSIENTS I1T
RADIATI01T BHVIROin-iEHT
W.A.Cordwell
IEEHS Trans.llucl. S c i . NS-1£, Ho.2, 30(1968)
Analysis Aethod3 to r e l a t e the c a p a c i t o r ' s
current generator to t h e b a s i c parameters,D(t),K ,K ,and t
~,usj.iig BJU:a li/ig technique's of c i r c u i t analysis^íÇograms•
g3tpjcession-rialn.ti ng. the -change—in-vo3rtage resujrting
from an absorbed dose f o r an a r b i t r a r y h u r a t ahapp J B a l s o
derived.
//,«
I 04
*""
j
t i
""
Í
'
j
'
I
' f?"
[
j
,
!.
HAHSIUST IOÜIZATIOK OTÜOTS I::TOC-D IK SILICON BY tf KBV
IE3B TranBUotione on liuoloar Science ^ , ^ - M ^ ^
(Annual Conference on Nuclear and opaoe. * . i i - . i
July 18-21,1966,Stanford university,Palo «l.o.Cal.
^
8872
BETA RAY DOSE DISTRIBUTIONS NEAR AN INTERFACE. Cross, F. T. (Batlelle-Northwest, Riohland, Wash.).
Health Phys.i 24: No. 1, 106-10(Jan 1973).
The doso distributions near tin interface of dissimilar matorials cannot be calculated by the usual methods unless a corrcction is inado for the differences in electron-scattering and energyloss properties of the apposcd materials. Interim approaches for
handling these situations are suggested. Although it is most accurate to weigh relative stopping powers (or ranges) by the beta
energy spectrum, in most cases it is sufficiently accurate to calculate the ratio for a single energy, e.g., the average energy of
the beta spectrum or at 500 kcV. The ratio of the atomic numbers
can be calculated as in the treatment by Cross. (Phys. Med. Biol.;
13: 611(1968)). (UK)
/ r. -7
tv I
«
DISTHI3ÜTI0H OF ABSOlffiEl) BETA ENERGY IH SOJ-ID KEDIA
W.G.Cross
, „ .
Canadian J . P h y s .
.
41,75(1969)
Chalk River Nuclear Labs., Chalk River,Ontario,Canada
\
•
Distributions of deposited bota energy have "been measured
in plane geometry, in Al and 1IB 102 plastic (C-^U^) f o r
seven emitters with endpoint energies of 0.16 to 3.55 KeV.
1 GAMMA-RAY INDUCED ELECTRICAL DISCHARGE I N A RADIATION SHIELDING
WINDOW.
Culler, V .
In Proceedings of the Seventh Hot Laboratories and Equipment Conference, Cleveland,
Ühio, 1959. p. 120.
j
An electrical discharge of a ary type radiation shielding window was accidentally
produced during the cleaning of t. hot cell. A brief analysis showing how gammairrodiation of a dielectric material can produce the large electric fields needed for
breokdown is given. A discussion of measurements on mock-up windows includes estimations of the irradiation time, dose, and the geometrical configuration needed,for the
electric field build up. The resting time needed for decay of the field is also d'iscussed.
Other measurements show that similar discharges can be produced in many glasses and
ether dielectric materials.
GAMMA-RADIATION INDUCED CONDUCTIVITY I N GLASS.
Culler, V . E . , Rexford, H.E.
In Conference on Electrical Insulation, 1961. Washington, NAS-NRC, 1962. p. 27.
publication no.. 973)
JMcosurcmonts were made on Corning bcrosilicate, alurninosilicate, and lead silicate
«losses and on fused silica. Source of gamma radiation were four fuel elements freshly
Ntioved from the core of a reactor. Temperature effecrs were observed.
\ ,
C-;^.:.'~"'AT?T.'.TICIT T::X'C::D C O N D U C T I V I T Y I N C L A S S E S
V.r:.Cul?;.o.',TI.E.?vi-.-.forc1 .
Coni'm-mo's on T?:i rlcictrü cs a.r.d Insulating llatericlsi.Ioru'on,
Tniti-t;!J..5oi. of r i r c t r i c a l L^.^ineorc,!^.';.
Measurements arc reported on fuiiod siljcajaluminosftlioat
silic?te,ancl alkali load s i l i c a t e £-lasoss. Tho Vic".::CS3t
HfeSH-it oifoct io fo-ur.d for fusca ci]iss.,v/here 10 Tui.z{ll?)/nec
produce an inor'JDce 1"j;r ?. factor of lO'^fXix Done and doce
///
rate depercdoKoy are ir.vesti£;.ted. Results are intorprêtcd in
terins of Royfse'e theory.
GAMUA RADIATION -INDUCED CONDUCTIVITY IN GLASSES
V.E.C3ner,H.E.Kexi'ord
Proo.Inst.Bl.Ene.(OB) U2,1462(1965)
Measurements are reported for fused silica,aluminosilicate,
boroeiljcate,and alkali-lead silicate glasses,vri.th dose
rates up to 10 rad(H20)/sec.For fused silica,which shows
the greatest effect,conductivity at room temperature in creases from 10~^° mho/cm to 10~15 mho/cm for 10 rad/sec.
Temperature effects are measured and effects are interpreted by Rose'e theory of photoconductivity.
f
f
I
/
'
38353
(BNWL-SA-247) DERIVATION OF AN EXPRI3SSION FOR RADIATION-INDUCHU ELECTRICAL
CONDUCTIVITY IN IONIC INSULATORS. Dau, Gary J .
(Battelle-Northwest, Rlchland, Wash. Pacific Northwest
Lab.); Davis, Monte V. (Arizona Univ., Tucson). July 16,
». o
I/O
18G5. Contract AT(45-l)-1830. 20p. Dep. mn. CFSTI
ffl.OO cy, $0.50 mn.
I In the derivation of the conductivity expression, a general theoretical development for the production of con- •
ductlon band electrons by gamma photons is presented.
When charge carrier mobility is considered, the development was limited to crystals having ionic bonding. Due
to difficulty in evaluating constants in the developed expression, all constants were combined into one constant,
which was considered to bo independeu» of temperature
and radiation. This constant was evaluated experimentally. A model was developed for predicting the conductivity of ionic Insulators as a function of temperature and
radiation dose rale. The model 1B C(T,P) = o(T) + PG
expf-W/kTKT)", where the first term on the right represents the ionic conductivity of the material without a radiation field present and the second term describes the
radiation-Induced conductivity. The term P represents
tne gamma photon dose rate in R hr~', G is an experlmentally determined constant, and W represents the
energy necessary to raise trapped electrons Into the
conduction band. The temperature dependence of the
mobility is represented by (T)\ Evaluation of experimental data for
alumina gave \V = O.OSG ± 0.014 ev and
G = 7.4 x IO"21 (ohm-1cm-|KsR-' hr). (auth)
1
1
I
1
GAI.IKA-IT?1)UCKD ..
.
ELECTRICAL CONDUCTIVITY IK ALUMINA
G.J.Dau,M.V.Davis
Kuol.3oi.Eng. j£,223(1966)
The theory of gamma-induced production of Elsujinran conduction
band electrons in alumina is presented.Consideration of chnrgo
carrier mobility limited investigation to crystals having
ionic bonding, A single trap model was developed,conductivity
as a function of temperature T and dofc rate P being
<^(T,P) = ©tT) + PGexp(-',v/kT)(T3/2), where
the second term gives the induced component of conductivity.
G is an empirical con tant and «7 the energy necessary to lift
electrons into the conduction band. Values are
G =0-036 í 0..Ç14 eV, G = 7-4 x KT^Cohnf 1 cm~ 2 E 3 / 2 K" 1h ) .
--—-— 5iTxnswrrraTjl4,521 (1967)
Desc
ribes experimental technioue for absolute"
surement of dielectric surface h
SSfS
us-
THE GEffiilUTIOIT ÜND DISSIPATION OP STATIC CHARGES Oil
DlELBCflilCS III A VACUUli
D.K.iiavies
ni"Btatic E l e c t r i f i c a t i o n " , I n s t . o f Phys.and Phys.Soc,
London 1^67, p.29
Describes an oxyorinental technique for measurement of
carrier mobilities baaed on determination of the decay
of the surface potential of a surface -charged dielectric
with a floating surface.
CARRIER TRAIISI'ORT IH POL'JliERS
D.K.Davica
J.Phys.D., Appl.Phys. £,162(1972)
Heports in vnciio nobility determinations using a charge
deposition technique.Eobility has also been determined in
two of the polymore impregnated with iodine.The 1 atter
increases nobility by about a factor of lo4.1£o suits are
discuaaed in terms of a hopping transport mechanism ana
indicate a significant barrier in transition between
crystalline and amorphous regions.Iodine reduces trapping
either by carrier acquisition and transport ,or by
htj5« exchange oonplex forraation.
i |
1
1,1
U~]
CHARGE TRAPPING HI POLYMERS
D.K.Davies,P.J.Lock
J.Electrochen,Soc. 120,266(1973)
THE PEJEÍÍRATION OP keV PROJECTILES HT SOLIDS
J.A.Davies
Conf.-670534-5 (AECL-2757)
August 1967
•' ].„,
Prom 15th Annual Conf. on Mass Spectrometry and Allied
»/o
Topics,Denver,Col .)
Discusses information on the penetration of energetic (0.5
to 500 keV ions) in solids. Technique consists in bombarding
the solid with a Eionoenergetãc beam of radioactive ions and
subseqiiently measuring the depth distribution of the embedded
radioactivity by a high precision sectioning technique.In
amorphous targets results agree well with Lindhard'.s theory,
but in oriented crystalline targets the mean penetration is
increased up to lofold by channeling of the beam along the
open direction or planes in the lattice. The dependence of thi
effect on energy and atomic number of the ions has been
ItQ
studied,also its dependence on radiation damage,surface
'/
imperfections,and crystal misalignment.
/
/
'
1
DERIVATION OP Ali EXPRESSIOir POR RADIATION-INDUCED
ELECTRICAL CONDUCTIVITY IN IONIC INSULATORS
J.G.Day
BNWI.-SA-247, University of Ari zona, September I965
I Oil BOH&iliDMElTT A1ID IMPLANTATION
G.Dciirnaley
Reports on Progress in Physics 32_>405(l96i>)
Atonic Energy Ros.Estublishraent", Harwell,Berkshire, England
ill
i
2225
ELECTRIC BREAKDOWN IN PLASTICS IKKADIATED
WITH CHARGED PAKTICLBS. Dcev, Yu. S.; Kruglyi, M. S.;
Lyapldevskii, V. K.; Sergeev, V. I,; Serenkov, V. I. Plast. Massy;
No. 8, 49-50(1970). (In Russian).
The tree-shaped cracks formed in polyfmethyl mcth.icrylate)
after exposure to fast electrons have been attributed to radiolysis
and secondary processes induced by it. It may be assumed that
the space charges created by the slowing down of electrons generate internal stresses in the material by means of electrostatic
interaction. This in turn causes the formation of trajectories with
greatly reduced mechanical and electric strength and with a short
half-life. The mobility of the molecules of the polymer is greatly
reduced in the vitreous state, resulting in low relaxation rates;
under such conditions the time of life of the trajectory may become
sufficiently long to create a discharge. The proposed mechanism
allows prediction of the behavior of organic glasses with respect
to the tree-shaped fissuring process on the basis of the physical
and mechanical properties of the material, (TTT)
'ULSSfl ÍJUCLEA1Í-RADIATI0IÍ-INDUC2D TRANSIENTS IN ELECTRONIC PARTS
AND MATERIALS (GODIVA IV and V ) .
H.-J. Degenhart, Y/.Schlnsser, and H. 3ruemmer (Army Electronics
Research and Development Lab. } Port Monmnuth, N.J.). Jan. 19°3,
56p. (A3--409519)
Pulsed nuclear radiation-induced changes in the electrical
characteristics of electronic parts and materials obtained in
twn experiments at the Gndiva II Reactor (L^s Alamos) are
described and discussed. The electronic parts investigated and
monitored during exposure include coaxial cables, resistors,
capacitors, rectifiers, and magnetic cores of various types,
values, and materials. Most of the parts during exposure sh*w
transient parameter changes which exceed the tolerance values
and then generally recover to their nominal values some time
after completion of the radiation pulse. Some of the data show
inconsistencies which prevent definite and quantitative i n clusions at the present time. In some cases, e.g., low and high
value resistors, HiCr thinfilm resistors of various values, and
ceramic capacitors, the data "SEõw certain repetitive patterns
I in the behavior of these parts which seem to permit a
I limited qualitative prediction of the responses of these J
components -inder similar environmental conditions. Ex periments at Godiva-type(pulsed) facilities are being continued.
,
i / Z
' t - A.
f/_
IJ.
BETERKINATION OP ELECTRON MOBILITY IN POLYETHYLENE
lãtSHn
f.An.ew.Phys. 28 22,268(1969)
(Techn.HohhBohulêrlnst.f.Blektronik.Muenchen)
K>:/.cr AÜAT^ICAL FITC^C-OCX-TO:: cra?.rji".?c I:T ^ ^ o i r i í D
,0 /-
?,A.^c:iin,C.,T.i:cüGiaiv;..
í p r a
« " H i f ' / . i , - " * ' - . - . .<•'•! - , p . - , T ' - , . l T " > . P T - - 1 - .\ ..j-*.j .11..j •.'.-... »-..it/f J X . W U ^ . « , . 1 i A j . t | t
O ' ~'~>1
(~iCiT>\
„• .—. — •.., j \j.y I c-1
1
Scuttlv. '.'i-.-S "' 11 tor.
AGO'
Paper presents an analytical method to determine the forward
backward, and net photo-coinpton currents in unbounded media
that includes the effects of electron multiple scattering.
The method gives the exact solution for the transport
equations modeling primary electrons (i.e.Coopton,
photoelectric,and Aucer electrons) and provides current predictions within ci few percent of the more complete konte
Carlo models. A code QUICKS! has been written to perform
these calculations for arbitrary elements or conpoxinds
irradiated with 10 keV to 20 KeV photons.Representative
results are presented which are directly applicable to . (
\
the calculation of the fields generated within an
irradiated dielectric cavity or of the magnitude of charge
trapped at insulator surfaces. Furthermore the forward
and backward currents in unbounded medium are upper bounds
respectively on the forward and backward emission currents
at vacuum-medium interfaces and are thus useful in worst
case analyses. Finally a simple model is proposed to use
the data on the photo-Conpton currents in unbounded media
in hand calculations of the spatial dependent 3 of the
nonlocal energy and charge deposition at interfaces.
18944
(SCL-RR-720086) HANDBOOK OF PHOTO-COMPTON
CURRENT DATA. Dellin, T. A. (Sandia Labs., Livermore,
Calif.); MacCallum, C. J . (Sandia Labs., Albuquerque, N. Mex,).
Dec 1972. Contract AT(29-1J-789. SOp. Dep. NTIS.
In a photon-irradiated medium, electron currents are created by
photoelectric, Compton, and other processes. This handbook presents accurate theoretical predictions for the amplitude of these
currents in 24 elements and 13 compounds for photon energies
from 10 keV to 20 MeV. While these predictions are strictly
valid only under photon/electron equilibrium conditions, a simple model employing the forward- and backward-directed current components is introduced to approximate the spatial dependence of nonlocal energy and charge deposition at interfaces,
(auth)
f? h
-r CONDUCTIVITY INDUCED 35T ELECTRON BOMBARDMENT IN AlíTHRACiaíE
^ S o l i d Stae Communications £,107(1966)
in
Using short pulses of non-penetrating electrons, electron and
hole mobilities are found to be about 1 ernes'"* V""-'- in the
case of single crystals.The field dependence of the collected
charge and the current gain observed for penetrating
electrons are explained by a simple model.
TABLKS OF CAPACITOR DISCHARGE IB TRANSIENT GAMMA RADIATION
ENVIRONMENTS
DeV/itt Landis
(Lockheed Missile and Space Company,Sunnj>vale,Calj£,)
Mar.1,1965. CFSTI % I.25 mn
AD- 617 918
Data on response of various capacitor types to various
transient gamma radiation environments are tabulated.
Tables were computer-generated . Values"represent averages
of many similar capacitors,
I
Í
58935
KILOAMPERE CURRENT AND CHARGE MEASUREMENTS OF A 2 MeV PULSED ELECTRON SOURCE. Dick, C. E.j
Whlttaker, J. K.j Sparrow, J . H. (National Bureau of Standards,
Washington, D. C ) . Nucl. Instrum. Methods; 104: No. 1, 131-6
(1972).
A current monitor has been developed to measure the electron
current pulse from the NES 2 MeV pulsed electron generator.
This monitor features low inductance and a risetime of the order
of a hundred picoseconds, enabling it to faithfully reproduce high
frequency components present in the electron beam pulse. In
addition, a charge integrating system comprised of an integrating
capacitor and a precision integrator has been developed to measure the total charge contained in the electron beam pulse,
(auth)
The monitor is essentially a Faraday cup with
low resistance and low impedance output which
permits to measure the incoming current as a
function of time, or to obtain i t s integral
by the integrating capacitor circuit.
1
RESPONSE OP WEAPONS DETECTORS TO FAST RISING SIGNALS
j
P a r t . I . T H E EBTBCTOR HESPOUSE _EDHCH0H
/?*
!•
W.C.Dickinson, A.F.Lauzo'n,
R . D . N e i f e r t , E . M . I i e n t I
-UCiB=.-4 675~("Car;
U M F i ^ r t ^ r í ò ^ X ã F T
7 5 ( r ; UMvFi^rty^ríTCrmòre^Xãv/rFnceTia
-Lab.—june-l-,1965,-C&n4r-ae-t-W-74O5-en-ê-4.8-í-5O-i
!M3ie
def i i t i fof response function
f t i
—- definition
and the convolution integral are presented for purposes of p
- pre di c ting -ãe1;e-c-tor-signalB-r"Re"Êrponse~fuxíctlóns" are"
.._cLç.±ermined- •"— "'
"
fluor photo di ode_d etector,a vacuum _Çomptpn_dio çtej
"* ~ fülly^êpTéteã silicon p-n semiconductor dê-
ELECTRICAL DISCHARGES IN ELECTRONIRRADIATED SHEETS OF
PLEXIGLAS AND EPOXT Resins
P. Dolcopoulos, E .Marx
ETZ(Elektrotechnische Zeitschrift) A, 8^,617(1967)
Experiments were carried oat with 3 MeV electrons,and a
current taisxijtxof 150 mmcro-AJsamples are moved under a
scanning beam with 2.5 cm/sec. Discharge figures are
similar to those by Gross,their average distance from
the electrode of incidence is given by U/3d where U the voltage and d the density of the material.It is found that
discharge figures obtained after irradiation differ from
those which might spontaneously develop during irradiation,
in that in the latter case there might be crossing channels.It is believed that this is due to partial discharges .
It is possible to fill the (empty)discharge channels with
a liquid of the same refraction index as the plastic and
thus to make then invisible.-Currents and charges have
been measured with an oscillograph.Maximum currents of
about 60 A were observed, duration of the discharge was
of the order of 200 ns for the negative and the same
\
I
value for the positive pulse. Thus a current reversal
was observed, the area under the positive section sonevhat
smaller than under the negative one. Before the discharge
the sample as a whole was,however, neutral, as was found by
measuring its total charge by dropping it into a Faraday
cage. (Tlit negative pulse corresponds to the discharge of the
electron layer, the positive one to that of the surface compensation charge which have opposite polarities. The difference
between the tiro is probably due to tfce fact that not all the
compensation charge did flow to the electrode, there being some
corona discharge. It is interesting to note that the two
charges can indeed be separated by their different relaxation
times.
t
"
"'
f
'
I
LIFETIME OF TRAPPED CHARGE IN ELECTRON'IRRADIATED
DIELECTRICS
J.Dow,S.V.Nablo
IEEE International Convention Record,"Circuit Theory..
Electrostatic Processes",Part 7,1, New York,l°-66
%xsg$i£!k Behavior of trapped charges in dielectrics produced by 2 MeV electron bombardment is investigated.
Charges are measured by deflection of a low energy
(lo keV) electron beam grazing the surface of incidence
of the beam. Total charge retention and charge decay curves at different temperatures are measured . CfesrgKxdEa
Lucite and aluminosilic^te glass gave nearly 100 y> retention,while polythene and teflon gave lower numbers.
Charge decays faster with increasing temperature; ifeExiai
decay curves can be represented as a series of exponentials
with short time components enhanced by dosage.
*
TIME RESOLVEU BLUCTHON DEPOSITION STUilIES Aí1 HIGH DOSE
JUTES Xir ijIELUC'i'KIGS
J.itovi, B.V.iíablo
IEEE Transactions Hucl.Sci. ITS 14,110.6,231(1967)
The grazing' electron beani probe' technique has'been
used to study the behavior of the electric field
external to planar irradiated sampèes in vacuo. The
trapped charge density is determiaed from the experimental results and its behavior during and
after irradiation studied with microsec resolution.
Secondary phenomena associated with bombardment
dose rates from 10 to 1 0 l 0 rads/scec include charged
particle emission,backscatter, and luminescence.
ThefcK&ispjsavalue of the trapped charge during and e
after irradiation has been determined.
\
45545
BULK-GRADIENT y-BAY INDUCED EMF IN p-TYPE
Si. Dubovoi, V. K.j Konozcnko, I. D.; Semenyuk, A. K. (Inst. of
Pbyslcs, Kiev). Sov. Phys.-Seraicond. (Engl. Transi.); 4: No. 8,
1349-50(Fcb 1071).
Translated from Fiz. Tekh. Poluprov.; 4: No. 8, 1575-6(Aug
I
1970).
12
A.
Measurements ot bulk-gradient cmf's induced by illumination
and 60Co y-ray irradiation were made on samples of p-type Si
<p0 K 2000 SI • cm) with longitudinal gradients of p. An ingot
was grown along the [111) direction by the Czochralski method.
After the distribution p(x) had been measured, the ingot was cut
Into samples having considerable gradients of p of the same sign.
Gold contacts wore deposited on the ends of each sample. These
contacts were nonrectifying In that range of temperatures T in
which the measurements were carried nut. The value of the yray-induced emf was determined with t ' e temperature of the
sample held constant to within ±0.1°C. (M.O.W.)
*"
|
,
I PUIS3D RADIATION EFFECTS IN CRYSTALLINE P0I.YETKYLEN2
.Ebeoglu (Atomic International,Canoga Park,Cal.)
j D.B.Ebe
ANS-ASTM-Conf on Radiation Effects fort Electronics ,Syracuse9i
HY,October 5-9,1964
Samples under M a s were exposed to radiation and cfcangeakf
conductivity measured.In particular, decay of conductivity
subsequent to each pulse v/as investigated, as well as
influence of temperature. A relation between the decay constant and the degree of ccystallinity v/as established.
f.
V
MEASUREMENT OF GAL3ÍA RAY INDUCED SECONDARY ELECTRON
CURRENT FROM VARIOUS ELEMENTS
P.J,Ebert,A.F.Lauzon
UCRL-14270 ,IEEE Nuclear Science Symposium,San Francisco
I965, CONF-65IOOI-I6.(Lawrence Radiation Lab ,Univ.of Calif<
California,Livermore).
Angular distribution and absolute efficiency for gamma
ray produced secondary electron^iáSüf11*! known for
development of fast radiation detectors,dosimetry,and
transient effect studies.These quantities were measured for
1.25 MeV gamma radiation, for elements with atomic numbers
6,13f29,48,82.Target thickness was a) approximately equal U
EBümaíEd: extrapolated electron range and b)l/lO of this
range,A difference betv/een total target current and total
forward current v/as obserbed which increased with atomic
number and target thickness,due to electron backscattering.
Application of Mar's electron transmission formula, gives
results in agreement with experiment.
/36
Y.Zk3VH\r.:.$T CF 0.M.1ÍA HAY i::DÍ.'CW) SECONDARY ELECTION CUIÍRÜNT
FROM VARIOUS ELE^I-ITS
P , J . R j í i r t , A .F.Musson
IEEE Tre.nsaotions on Kuoloar Energy
I» 735(1966)
A»a©
VACUUM DI0D3 DETECTOR FOR MEASURING HIGH INTENSITY
GAMMA-RAY FLUX
'_ pp.J JJ.ybert
A._F.Lauzon
f_
f
" R"e v' . Si c ij. ' i8n s t1F .7j 8 ,41 774 7 (1967)
(1967)
-DirscrrrbeEr-a"-Compt0n""va"(íUüní~a"eirect"òr.A
theory of e-eul-t i-x
leiec-tor . sensiii-vi-ty—i-s-g-i-ven,—posi•
t-i-ve-pulsee-r
i
i
i
i
t
i
l
r e s u l t i n g í'rom electron _lo^^f_j^laj^e__and_negative
pulses"due t o èTêc"fròh""gáin are mentioned. In the
stead y—state—mede-a- sensitivity—©f—10~^2-A—i-s—f utind i—
___Al n .ear_signal_s._gr.eaier_ox_e<iu.sl^A^jclQ2^^
found corresponding t© a 1.25 MeV energy_^dose_ r a t e
—;~crf~IXeai7er~i0~ íl/h^ f^T"nfa^T~pTiTsê~sT~*/sc'ri'I'õgrãni"s
9-í-pul-se—shapes—aee-g-i-v en .Mi-iiifaum—srgnai'Tneasurabte ~
d ep end s j> n_s ensi t i ylity_o_£_ r_e.c.ard i ng_sy_s± em_v
p with a 50
5
_^
2xÍ0~3À ©rO.i V into a fast scope
terraination"i~Curreirtrg~Up~t"ó~"lO2x~w^re raéasüreâ'. In fhT"
dynamic- ease--"the--travei—tirae-ôí--the--eiet!trons"~d^pená'—
itt^
—
on plate voltage and on rate of rise ef plate voltage.
I.Í13ASUEE1..-B1TT OP X-RAY INDUCED ELECTRON CURRSTTS PROM KE'l'AL
TARGETS
UCRL-50691, June 23(l§69j_
Discusses photoelectric diodes (PHD) mostl;/ for X-rays with
energies between 10 and 100 keV, giving forward to 'backvrard
yields,quantum efficiency as a function of angle and of
thicknecs.u'ith low - energv X-rays saturation i s reached
vãth thicknesses of 8 ng/cn .Sone measurements are shown
for reaching secondary electron equilibrium with Al
and PT) for the case of Co 1.25 KeV radiation and thickness up to 2.6 g/cm .
t
52492
FURTHER DATA ON GAMMA-INDUCED ELECTRICAL CHARGE AND COLORATION OF SHIELDING GLASSES.
Eckles.T. W.jMingesz, D. P. (Argonne Nationai Lab., 111.).
pp 143-7 of Proceedings of the 18th Conference on Remote Systems Technology, Washington, D. C , November 1970. /Farmakes,
Ruth (ed.). Hinsdale, 111.; American Nuclear Society, Inc. (1970).
From eighteenth conference on remote systems technology:
Washington, D. C. (Nov 1970). See CONF-701132.
Two cerium-protected shielding glasses, now available commercially, have been shown by irradiation testing to be immune
to spontaneous electrical discharge during total exposures of at
least 1 x 108 R at exposure rates as high as 1 x 10» R/hr. One,
a lead glass of 3.27 specific gravity with greater than normal
stabilization ajalnsl gamma darkening, is Code 84S9 produced
by Corning. The second, a borosilicate glass of 2.53 specific
gravity which also contains greater than normal stabilization
against gamma darkening, is HS253G/25 by Schott Glass Inc.
In addition, this second glass did not discharge electrically when
given an impact shock immediately (within 20 min) after cessation
of irradiation. Such glasses should be of Interest to buyers of
shielding windows where the first thick slab of glass is subjected
to total exposures >5 x 10e R at rates as low as 40,000 R/hr. These
were the conditions under which the March 1970 incident of
spontaneous discharge occurred in a shielding window installed
in an active hot cell, (auth)
|
\
|
|
|
f» »,
'TÍ/
5053
TRANSIENT EFFECT OF NUCLEAR RADIATION OH THE
DIELECTRIC PHOI'ERTIES OF CERAMICS AND PLASTICS
AT MICROWAVE FREQUENCIES.
D. Edclson, H. E. .laeRor and 3. C. Williams.
Electrical Insulation, Duck Hill Fall3, Pennsylvania, 19G5 (Washington: National Academy nf Sciences, National Research Council, 1960),
pp. 10-10.
I
A series of measurements was undertaken to study short-time I
phenomena In several representative plastic and ceramic materials!
Including polyethylene, polyletrailuoroelhylene, polystyrene, alumina!
magnesia, silica and bcryllta. The frcciucncies were In the 1-10 Gc/s
ranRC,corresponding lo L, S and X bunds. A resonant cavity method
was used and movlnRfllm records were oblnlncd of response curve
oscillocrams. The Irradiation was performed In a General Atomics
Tri|;a pulsed reactor of the swimming pool type. Results are given
In detail.
R. N. Iiasu
IA I
'
I
ENERGY RESPONSE AND EFFICIENCY OP C0Í1PT0N AND ÍH0T0ELECTRIC
COirVBRSIOH DETECTORS
Tech.Memo L-l6l,EGG-ll83-1252,July 26,1966
Gives
1
137 Cs 1.85X1O"?" A per
60 Co 3.77xlO"x
Jf %
R/sec
A per R/sec
I
STATIC VERSUS DYNAMIC SENSITIVITY OP SEVERAL WEAPONS
DIAGNOSTIC DETECTORS
Ml
EGG 1183-2236,May 1970.
Describes results of the measurement of dielectric detector
sensitivities as a function of pulse width (l ns to 4
micro s ) . Results showed the dielectric detector to
be independent of pulse width.
Comparison with the L 125A
detector showed, howeisr,
that this latter (vacuum) detector showed some non-linearity.
However,since the current from the vacuum detector was small,
the error involved was very large}thus no definite
conclusions were possible. Yet, the experimenters could
think of several reasons why the dielectric detector
might b e not linear, but none while the toacuum detector
should b e non-linear. This motivated further research
by Artueo (üGG 11Ô3-2277) which showed that the nonlinearity appeared to b e due to the cable response which
was causing distortion for the less sensitive vacuum
.
ok
detector.
.. . _.. ..-.
I—
ELECTRON BOMBARDMENT CONDUCTIVITY IN ZHTC SULPIDB
W.Ehrenberg,N.J.Hidden
J.Phys.Chem.Solids J23.,1135(l962)
Measurements on vacuum deposited films of zinc sulfide and
onplates of wurtzite with 2 - 5 0 keV electrons are reported/
for blocking contacts.Only the induced currents,not the
primary electron currents,are investigated. The effect of the
range of the electrons with regard to sample thickness is
discussed. It results that films respond to steady bombardment only if the electron energy exceeds a threshold value
necessary to guarantee that the electron range is almost
equal to sample thickness,while the crystals respond only
if the bias is high enough so as to exceed the potential
drop set up in the crystal when all deep traps are filled.
'
j
j
I
b«
!
.
/4f
„.
f"
j'
:
PIíiíBílUTIOlI OP ELECTRONS DITO LUMIITESCEÍTT MATERIAIS
V/.BhronborG, B.li.N.King
P r o c . P h y s . S o o . 81,751(1963)
The glow production in a number of phosphors due to
narrow bundle of cathodo rays is studied, giving electron
ranges in the 10 - 80 keV energy range. They range values
are found to bo proportional to the integrated path
lengths given by Bethe's formula. Energy dissipation
values aro al«o determined.
IA tr
ELECTRON BOMBARDMENT INDUCED CONDUCTIVITY IN FUSED SILICA
W.Ehrenberg,V»B.Gutan,L.K.Vodopyanov
Brit.J.Appl.PhyG. 11,63(1966)
Cathode ray and beta ray induced conductivity is studied,±JOX.
•Fused natural quartz samples show the weakest effect,
while crystal samples and amorphous spociments give higher
results. Amplification factors of up to 300 are observed.
Metallic impurities reduce the effect. An interpretation in
terms of recombination centers and an alternative one in terms
of exciton generation and decay are offered.
/TO
L
COLUNKAR IONIZA'i'ICir III TILLS ELECTRON BOliBAHDIiESJT COlIXfUCTIVTiTf
OP AftOMHQUS IUIKL.ECTKICS
K.Bhrenberg,B,Gosh
J.Phj-c.C. Ii-oc.Phj-s.Soc. (Solid State 1'hys. )2_,152(lÇ6</"! .
Conduction induced in.,aresenic .trisulphide films by
beta and cathode rays is studied as a function of film
thickness and incident KKEEIQCX beam currents»Films between
2 and 20 micri-ra have been studied,beam energy being
.sufficient for complete penetration of the films. The
majority of the carriers is generated along the paths of
the primary electrons and only those escaping recombinatior
in these columns are available for conduction. The low escape probability is probably responsible for absence of
saturation of the induced conduction with voltage bias.
Under steady-state conditions the free path of the
carriers v/hich escape columnar recombination is normally
long enough not to reduce the efficiency of their
,
^collection appreciably.
,
y
f
j
j.
}
j
[
IVth International
Congress on Radio biology and Physical
Chemistry of Radiation.
Enian,France
29 June-4 July,1970
Abstracts, p.64
THE USE OF CAF-tHn THERMOLUKIHESCaKE DOSIMETERS FOR HEASOR1HG
ELECTRON-DOSE * DISTRIBUTIONS IH DIELECTRICS
H/RGARETE EHRLICK
\
I t has been pointed out in the U t e r « c u r e 1 ' 2 ' 3 t h a t , for t h e high e l e c t r o n
flucnces encountered per pulse In modern h i g h - c u r r e n t pulsed e l e c t r o n
g e n e r a t o r s , energy deposition In d i e l e c t r i c s occurs «t shallower depths
Elian In conducting media; and that, with an Increase In e l e c t r o n f l u e n c e ,
lliere U s s h i f t in the l o c a t i o n of the penW of the depth-dose curve
coward shallower depths.
Although the dynamic range of theraolualncoeoncc (XL) doslmetry eystetu
recludet t h e i r use for the very high fluences for which the above
lurves of response-in-depth v l l l be presented which demonstrate that,
;v*n for the relatively low total electric charges Injected Into the
!a£\, la Che present experiments, there IB a significant difference
*nd computed depth-dote curves la aoeevhat saaller. OOver
v< the charge
range Investigated, no significant change In peak loc«tl
rich a change
In collected charge could be demonstrated.
1
2
3
4
B. Uckner, I. Kohlberg, S. V. Hablo, J. Appl. Phyi. 36, 2064 (1965)
E. Kennedy, I. Kohlberg, Trans, ta. Kucl. Soc., 14th Annual Meeting
p. 407 (1968)
R. Little, J. OtCeaen, F. K. Cblldert, IEE Trans. Hue I. Sel.. KB*16.
250 (1969)
K. J. BccEer and 5. H. S e l t s » , NASA SF-3012 (1964), and private fi
connunlcatlon
f
":
5589
DETERMINATION OF KTLOVOLT ELECTRON ENERGY DISSIPATION VS PENETRATION DISTANCE IN SOLID
MATERIALS. Everhart, T. E.: Hoff. P. H. (Unir. of California, Berkeley). J. Appl. Pbys.: 42: No. 13, 5837-46(Dec 1971).
A universal curve of energy-dissipation range vs normalized
electron energy is proposed, which includes the average atomic
number Z of the material being bombarded in the energy normalization factor. Range —energy expressions of the form R = kEf,
derived from the Bohr-Bethe energy-loss relation, are valid
over limited energy ranges, but the exponent a differs for materials of greatly different atomic numbers over the same energy
range. For the aluminum/silicon dioxide/silicon system used
here, Ro = 4.0 EB(keV)'-'5^g/cm2 was found accurate for 5 <
Eg < 25 keV. Using this value of range, and taking the steadystate electron-beam-induced current through a thin insulating
layer of SiOj as a measure of the energy dissipation in that layer,
an energy-dissipation (depth-dose) function was determined that
should be valid for 10 < Z < 15. Using this normalized expression
\(y) = 0.60 + 6.21y - 12.40yz + 5.69JT3 and the range RG, the energy
dissipated at any depth may be determined, and hence the carrierpair generation in semiconductors, light generation In phosphors,
etc., may be predicted. An expression relating the depth-dose
function to the applied voltage drop across the oxide provided an
independent check on the experimental m e a s u r e m r è t f
v""
L
r
F
22869
2.00-MeV ELECTRON DEPTH-DOSE MEASUREMENTS
IN ALUMINUM, COPPER. AND TIN ABSORBERS USING A RADIOCHROMIC DYE FILM. Eisen, H. (Univ. of Maryland, College
Park. National Bureau of Standards. Washington, D. C ) ; Rosenstein, M : Silverman, J. Int. J. Appl. Hadiat. Isotop.; 23: No. 3,
97-108(Mar 1972).
The use of radioohromlo dye films (hcxahydroxyethyl pararosaniline dye cyanide in nylon) for electron dosimatry has been
extended to absorbers with atomic numbers in the range 13 to SO.
The depth-dose profiles in slab targets of aluminum, copper, and
tin irradiated by a plane parallel 2.00-McV electron beam are presented for Incident beams at 0, 30, and 60 degrees with respect
to the surface normal. Absolute energy deposition per unit fluence
was determined by using calibrated films, a fluencc measurement,
and a stopping-power ratio correction. The resutis are compared
with the ionizatlon measurements of Nakai and to the theoretical
calculations of Bcrger and Siltzer; all agree within 10 percent,
The stopping-power ratio, necessary to convert dose in the dye
film lo absorber dose at that point, is determined three ways and
the results compared. The three techniques range from a detailed
computer transport calculation yielding a variable stopping-power
ratio with depth to the use of a constant stopping-power ratio obtained from tabulations. It is demonstrated that the use of the constant stopping-power ratio gives depth-dose distributions that
differ by no more than 1 to 2 percent for aluminum, 3 to 5 percent
for copper, and 4 to 8 percent for tin from the results obtained
with the more rigorously evaluated stopping-power ratios, (auth)
(UK)
/trf)
'** "
L
29988
TEMPERATURE OF THERMAL PEAKS DURING
IRRADIATION OF IONIC CRYSTALS. Eremin, L. P . ; OblivantBev, A. N. (Tomsk Polyteohnio Inst., USSR). Izv. Vyssb. U'
Ucheb. Zaved., Fiz.; No. 3,149-61(1971). (In Russian).
The effects of temperature on the decomposition of polycrystalline samples of NaNOj during irradiation with 5-MeV protons and
20-MoV a particles were studied. In the In G vs 1/T graph, two
regions were noted that differed in their energies of activation.
The common boundary of these two regions was 324°K for protons
and 345°K for a particles. (K.S.W.)
GAMKA-RADIATICH-INDUCLD CONDUCTIVITY IN HJCLiiAlt SHIELDING
GLASSES A3 DlSTEitl.iliiLiD BY SPAC£ CHA3GK DECAY
F.M.arnsberger,T.E.McGary
11th Hot.Lab.Proceedings,ANS,November 1963,page 383
(New York,Nov.18-21)
Glass samples were charged by irradiation with 2 Kev electrons from a Van de Graff generator. The dEsayxEfxtòB charge
was measured by discharging the samples at various times into
a capacitor arrangement and measuring the resulting voltage.
Keasuremnts were taken at various times after irradiation,
with and without gamma irradiation. In this way both the
normal charge decay and the speed-up of. this decay by
gamma-ray-induced conductance was determined. The influence
of the cpmposition of the glass, of gamma ray intensity,
and of temperature were à&tsxnx observed.
Í
;
'51
I
ji
F
46520
ÜV DOSIMETRY BY ZnS ELECTRET DISCHARGE.
Fabel, G. W.j Henisch, H. K. (Pennsylvania State Univ., University Park). Solid-State Electron.; 13: 1207-12(Sep 1970).
A method of uv dosimetry is described which depends on electric depolarization in single crystal and powder specimens of
ZnS by the incoming radiation. The residual polarization can be
measured by optical or thermal readout procedures. In both cases,
the mechanism Is electronic. The dosimetiic characteristics of
those systems are described and comparisons made with corresponding doslmctrlc procedures based on pyroelectricity and
current-glow. Measurements of the type described also yield information on trap distributions in Insulators, (auth) (UK)
«
POLYMER THERMOELECTRET DOSIKETKY
G.Vf.PabeljH.K.Honisoh
Phys.Status Solid (a) 6,535(1971)
Measurements are reported with nylon,mylar,polystyrene,
and teflon eleotrets. Samples wore irradiated without a
covering electrode on the exposed surface. Polarization was
measured by ,onitoring the surface potential with a
contactless voltmeter probe. The effect of storage environment, forming temperature, and forming field were
studied. Except nylon, all materials gave stable electrets
under normal conditions. In the presence of X-rays or o^ t
thermal neutron irradiation they undergo a rapid cumiaulative discharge. Total dosage received can be inferred from a
comparison of initial and final polarization. Por 50 kV X
aHH,l mR is easily detectable.Higher sensitivities
are believed to be attainable in principle. Similar high
sensitivities are reported for neutrons.
I STUDIES III PEIÍETRATIO1J OP CHARGED PARTICLES INTO HATTER
\
j TJ.Fano,ed.
'
;
Htl.Acad.Sei.,Ntl.Res.Council, Publication 1133 (1964)
• Collection of articles,including extensive tables. The following
definitions of "Range" are given?
;
-"Range" of a particle should indicate its"mean"(rectified)path
I length from its relevant point of departure to the point where it
I comes to rest, that is where further displacement is not detectab' le ~ "c.s.d.a." indicates the Quantity ,0 /,„/, \-l ,„ . . .
i
j (dE/ds) dE whxch
J represents the range in the continuous slowing-down approximation.
I -"Projected range" indicates the mean depth of penetration into
:
the material, that is the mean projection of a particles path on
its direction of incidence on the material. - The "c.d.S.a."
range is the path length which a particle would travel in the
! course of slowing down ,in an unbounded homogeneous medium,from
• initial to zero energy,if its rate of energy loss along the eni tire track length were always equal to the mean rate of energy
j loss. Thus it differs from "Projected range" and "Extrapolated
j range",which are usually defined with reference to transmission
j through a plane-parallel absorber.
1323
PHOTOCONDUCTIVITY IN IRRADIATED DIAMOND.
Farrer, R. G.i Vcrmeulen, L. A. (Uniy. or the Witwatcrsrand,
Johannesburg). J. Phys., C (Lotion): 5: No. 19. 2762-8
(3 Oct 1972).
Measurements a r e reported of the pliotoconduction spectra of
several electron-irradiated type la and type Ila diamonds in the
neighborhood of the GR1 and ND1 absorption systems, and the abeorption lines which have been labelled GR2 to GH8, R9, and H10.
Minima occur in the photoconductioti spectra at the positions of
maxima in the GUI absorption system. Sharp peaks which persist
at temperatures down to 8°K are observed in the photoconduction
spectra at the positions of maxima in the ND1 absorption system
and the lines GR2, etc. Mechanisms which might give rise to these
sharp photoconduction peaks a r e discussed, (auth)
\
DISSIPATION OF CHARGE L4YERS Hi DIELECTRICS
G.L.Forreira, B.Gross
Hev.Brasil. Fisica 2,205(1972)
The paper discuoseo the dissipation of a uniformei;/
charged layer (box distribution) embedded in a dielectric
with, intrinsic conductivity. It is shovm that an exact
analytical solution can be found. Applications to the
short-circuit caso arc jivea.
157
\
CUK1ÍI2ITS AIÍD- CIíARGES III RADIOELECTitSTS
G.F.L*Ferreira, B.Gross
In: ELectrets,Charge Storage and Transport in Dielectrics",
Conf.lJ.ani, October 8-13(1972).-The Electrochemical Soc.
(1973),
The paper discusses the discharge current produced by the
detrappins and transport of charge carriers from a raonopolar charge layer located deeply in a dielectric. For the
cases of. no retrapping and of fast retrapping in a single
trapping level it is shown that the initial current
rise is independent of the shape of the charge distribution. Exact analytical expressions for the external
current and for the space-charge density as functions of
time are given. They are valid as long as the space charge
does not reach one of the electrodes.
CURRENTS AND CHARGES TS BADIOELECTBETS
G.F.L.Ferreiraj, B.Gross
J.Honmetals 1,129(1973)
}5
7
SC-DH-72 0118
COMPTON DIODES: THEORY AND DEVELOPMENT FOK RADIATION DETECTORS
T. R. Fewell
•
.
Instrumentation, Dosimetry, and NTS Projects Division, 3313*
/ /
Sandia Laboratories, Albuquerque NM 87115
Printed October 1972
The Coinpton diode is examined from an engineering aspect. A brief operationaltype discussion of the detector is presented; each component of the Compton diodeis examined in both theory and experiment. Special- emphasis is placed on designing a Compton diode which is very reliable but simple in construction. H is shown
that one can design a detector whose signal is nearly equal to the number of electrons
impinging upon the collector. At radiation levels and rates used in our experiments,
the detector is essentially insensitive to problems such as charge buildup in dielectric, electron backscattering, and other factors. Some design hints are also givento
solve problems which could occur at higher radiation levels.
OBSERVATION OF RADIATIOII-IITDUCE]) THERtiALLY S2ZKEEKESSX
ACTIVATED iffiPOLAMZÀaiOlí IN LITHIUM FLUORIDE
D.E.Pields,P.R.Lioran
Phys.Rev.Lett. 29,721(1972)
A large pennanenTT electrical polarization can be induced
in LiF by ionizing xadiation, in particular X-rays. Specific
radiation-induced polarizations, after thermal depolarization
(e.g. cooling) can be regenerated optically (e.g. by
illumination with optical light and simultaneous exposure to a polarizing field), but not by thermal repolarization (e.g. heating with an external field applied).
Rate parameters characterizing thermal depolarization
differ from those of other thermally activated processes.
The effect has a signal-to-noise ration comparable to
simultaneous thermoluminescence measurements, which suggests
practical applications in dosimetry and other fields.
A discussion with regard to radioelectret properties
is given.
STUDY OF EFFECTS OP I0HIZIHG RADIATI013 III CAPACITORS
T.W.Hlanagan,J.W.Harrity
Gulf General Atomic Report
GA - 10002,April 1970
Reports measurements of RIC (rad.induced cond.) at
10' to IO1** rad/s for Teflon.
.
'
j-j $
'
\
«•«>•»<
I
•
j'
(AD-641654) DEVELOPMENT OF A KIGH-IliTBRSITY SOLIDSTATE GAÍSÍA-RAY DOSIMETER SYSTEM. F i n a l Technical Report.
F l e t c h e r , C.L. (General Dynamics/Fork vYorth, Tex.)»
J u l y 18, 1966. Contract N228(62479)67947. 63p. (USKRDLC-53). CFSTI $3.00 cy, SO.65 mn.
p
Design, construction, and testing of an integrating
"gamma-ray dosimeter ^*-* high dose rates are discussed. The
sensor is a silicon surface-barrier detector operating as a
current device. The detector output current is integrated on
a capacitor. When the voltage on the capacitor rises to a
predetermined level corresponding to 10 rad-equivalent-air of
gamraa-ray dose, the capacitor is discharged and the instrument
produces an output pulse to signal the event. The number of
output pulses indicates integrated dose, and the pulse
repetition rat« indicates dose rate. The detector proper is
cooled with a thermoelectric cooler to minimize and stabilize
leakage current. The instrument is designed for operation
in the dose-rat© range of 10 to 100,000 rad-equivalent-air
per second. The detector is constructed to make it function
as a Bragg-Oray device over the gamma-ray energy range of
80 keV to 12 l.eV. The detector is reasonably iaotropic.
Cumulative errors due to. all causes arc less than about
30;£.The electronics is insensitive to gamma-radiation
transients for dose rates up to 10" rad/s.Results with
radioactive sources,a fast-burst reactor,and brerr.sstrahlung ,
•culses are given.
_
—
/•..
f
•
" " " • • • • • •
"
•
-
[
CI?ICAL LCDVlATICir 0? ELECTRICAL .BÜÁN L.'J.DI^G ETIJHGY
0*i Sft.lCOIT^UCTORS
li.A.Foos
J.Apíl.Rç-s.£3,514(1572)
,
'
Charçirisi effects of semiconductors (with 10-* to 104 Ohm c:::)
are investigated.An electron beam io scanned alon^ a se;.;iconductoa? tarjet parallel to an adjacent r.etal reference
electrode.The loading edge of the beat:: charge? the cer;inconductor to a level determined b; surface and bulk conductivities of the conductor.This conductance varies
optically exciting carriers in the ceir.iconductor thereby
altering the nr.rcimun charge-up potential -JÍVA thus the
total electron landing eiier^.-.The potential c:.n be deter' mined b; measuring secondary enission current fro:.i the
tarjet.Tite electron landing enerj; can b e changed b;several hundred volts on Si and CdTe targets depending
upon the photon input fliu:. Frisar;, currents irerê 1 0 ~ ^
dovrn to 10-7 A,beam EKEX;.: voltage 1.5 keV. '.
•
r
~
~
'
._.
' tj
„„,..
f
j
i
j
' Í •:
CONDUCTIVITY INDUCED IN INSULATING MATERIALS BY X-RAYS
J.E,Fowler,F.T.Farmer
'
.'
Nature(London) 211,317(1954)
-8
Measurements on polythene show conductivity ~ (dose rate)
.
Small doses,below 104 r, create traps and deep levels which do
not decay with time. For perspex the conductivity increases
linearly with do3e rate,independently of temperature, indicating a uniform trap distribution in depth with a gap between
superficial and deep traps.
/7C'
1Jd
I CONDUCTIVITY INDUCED IN POLYTETRAFLUOROEHTYLENE BY X-RAYS
i J.F,Fov/ler,F.T,Farmer
Nature (London) 1X4.» 136(1954)
Measurements in a vacuuijj chamber sho conductivity proportional to (exp - V//kT) with W = 1.1 oV before and $.5 eV during
irradiation. D03S rate dependence indicates a trap distribution
which is pHajffiExAiBííítt exponential belo?/ the conduction band.
After irradiation has ceased, the conductivity deccreasea
slowly, talcing 6 h at 80 to fall to 10$ of its former
value.
1
IIDUCBD IN UNPLASTICIZBD "PSHSPEX11 BY X-RAYS
J .I' .Fowler,? .'i1. Farmer
Nature 12^,516(1955)
It is found that the conductivity increases to the 0.55 power
with doae rate.
''7
CCÜiMJOTlVlTY KIAJCEü IN MICA BY X-RAYS
J.P.Fouler, P.'1'. Farmer
Hature r & , 640(1955.)
CONDUCTIVITY INDUCED BY X-RAYS IN P0LY2THYLEIIS T2R3PHTHALATEI
A POSSIBLE INSULATOR TOR RADIOLOGICAL APPARATUS.
J.F. Fmvler, and Dr.F.T.Farmer. Nature v.175, n. 4457, p.590591, 2 Apr 1955.
•
'' '
Measurements of the conductivity induced by x-rays in "llelinexf1
(polythylone terephthalate sheet) have been made, using the
d-c amplifier technique.
r
•
}.
j
j
Í
X-RAY INDUCED CONDUCTIVITY IN INSULATING MATERIALS.
Fo-.vler, J.F.
Proc. Roy. S o e , 236A, 464(1956)
A co-ordinated explanation of the conductivity induced by ionizing radiation in solid
insulating materials, including amber, mica, and a number of plastics is put forward. A
model based on the conduction by free electrons and including the presence of electron
trcps is proposed, and the theoretical predictions based thereon are shown to be in good
agreement with the experimental results. The dependence of induced conductivity and
of the subsequent decay upon ternperoture end dose rate have been investigated. Physical
parameters are given for each material: Recombination cross section, number of traps,
their distribution 'n energy, mean distance diffused by free electrons and probability
factors of release from traps. Results suggest that when crystalline regions are present
in a material (e.g. polyethylene), the boundaries of these regions provide trapping sites
in addition to traps of unspecified nature present in completely amorphous materials.
p"
!
\<S0
••( í
SOLID STATE ELECTRICAL CONDUCTIVITY DOSIMETERS
J.F.Fowler
eds.
I InsRadiation
i n .ttaaiaxion Dosimetry,
nosimeTiry, 2nd
<ína ed.,
e u . , Vol.11.P.H.Attix,'.V.C.lioesch
vux .J.J
j Academi c rress,New York 1965, p.291
SPACE-GKARGE EFFECTS ON EMISSIOW-LIMTTED CURREUT PLOW IJÍ
INSULATORS
'
R.I.Frank,.T.G.Simmons
J . A p p l . P h r s . 38.,832(3 067)
Pnpef* extends irell-krown theory of effect o° elector traps
or cv.rrpnt-vo? tare characteristic and rpacs ehr.vf? i"ror'
npnoG-charge liritod :nto orisnion-charrie ^i^ited rir-ion. -'.
j
THE THÍSHMÁLLY STIl-IULATEi) EM5' ARISING IN
SOLID HYDROCARBONS IN THE PHBáBlfCE OP A Ti2.iPERilTUI-U3
E.L.Prankeviol^V.L.Talroze
Soviet Phyo.-Solid State 3.,13l(l96l)
'Fiz.Tverd.Tela 3,180(1961)
'Smmplfe"s~of" 1x3x5-mm-%7ar - i r r a d i a t e d - a t - -2002K—- with — j —
-1.6 -MGV-electrons.....During._heating_.up. "bursts"
|_
pf EiMF were ot>serveâ v/ithin such temperature ranges
"where""stffõhg" reeorabination~and strong-increase--in - •electrical- conductivity, were. .be.lieved._to._occ.ur,._.The
:
temperature graáent v?as of the order of 20SC.
"During isòthérmaT"hèa"t'Irig" nó EMF' wás~'Hfeaisarsâx3íx
-observed-, "The-reason for the -effect-is seen-in-an-:.
..c
..inhomogeneity .in_the current carrier density_wjf-thin^^
Volume were acrriers are trapped. "
'
•
I
\
INVESTIGATION OP THE MOTION OF CARRIERS IN ORGANIC SUBSTANCES
E.L.PrankevichjE.I.Balatanov
Fiz.Tverdogo Tela 1,1667(1965)
Conductivity of thin films of paraffin wax was observed under
3 — 8 keV electron bombardment« Current transients decrease
in amplitude with increasing number of electron pulses,
reaching eventually a steady state value,The amplitude
reduction is due to a polarization effect caused by the
internal field produced by the ionization-induced charge.
•
f\
i
|
i
TO'
EFFECTS OK ELH'CTRONf'tG PARTS AMD /-fATERIALS
Tv
P.9oort
<°port K
"—
H 7,,-J'IM
V -TMVie l^— 3 e t ) t « l ^ l^S?»
'.'o. , O w e r ; o , H . Y . E l e c t r o n i c s C e n t e r , D e c . 1956 r
rjuari-.»rly
jar-
Msrisu.r'rVTi'int.'J ón TiicSjT.ylr.r, and "^olyytyrsne at the
Physics TntTrrvational .Viv=inceâ ~~i3?i-;h V -3HV f a c i l i t y
ara rsporterl.O^p-ncitors -.«re tested t o deterrr.ine
induced curr^'it .?.::£ voçlonishraent ch?.r'73 as a function
of voltage.Out», for e^.ch d i e l e c t r i c exposed, t o the
short pulse and high rs.ciip.tion level are orssentscJ.
.
.
.
•
•
.
REACTOE ATJD LIJTOAR ACCE1.73RATOH
.
.
.
•
•
f
.
liraiCFJI) EFFECTS IT? HTELKC-
P. A. 3?r an'cc vn Vy. M. L........ , . . ^ ITD^E Trans.liunisar S c i . (iTSA) NS-1J. ,Ho.S. 8(1966)
Nuclear radiation ir.fluocd currents as obt?.i.Yi<=.c, vri.th pulsed
reactors on sevnral oornernia] capacitors nr" compared
with those obtninrd by LI1TA0 electron b^ams.liffectr
• •
of aT->T)3ied vo].tage,feomf3tr7/-.dor.e, av.õ dose r a t e a r e studiec
for mylaT,jrn]vstyrene,mica,taTitalian,glasn. and ceranio
capacitors.Lnterjirotati on i n torp.s of a suitable Tnodel
i s fiven and characters s t i o parem, et or? established.
The reJstivn eff«íítiven^f?f? of farra pnd ne^.tron radiation
i s e.lso invesitj p;ate<3 • TAtovy I'I '
'
"
-0
•
-
-
»
•
-
If V is the voltage and G the capacitance, the induced
current i y is given by i = ^ - ^ ) G V / Ê £ . Then
i r = C V ApÊ ( t ) + Z K /00 " e-í*-*' ^ n Ê(t' )df .
n S-n- . .
In a mixed rad.field E= Flf+D ,jrhere F a prop.const, relatin,
^o absorbed neutron dose rate,lfrefers to neutron dose rate,:
Dto e^E^as assuming a l l garama loss due to ionization. The
sohene below gives i r =j i-Idi/dt ,T=RC and
i(t)/CT\=(PR+l)K(t) where R=li/» .Then
a plot of the left hand side of this Eo.
versus R for different shielded bursts
results in a slope of KP and intercept
K(t). The ratio of neutron current to
total current due to the mixed field
ie therefore
^
J
itotal=FR/(l+FR)
j
[,. ,
j
21151
(IBM-6G-825-1944) REACTOR AND LINEAR
ACCELERATOR INDUCED EFFECTS IN DIELECTRICS.I
Frankovsky, F. A.; Shatzkes, M. (IBM Federal Systems!
£>iv., Owego. N. Y.). Mar. 19G6. 39p.
I The currents induced by nuclear radiation from a pulscL
reactor on several commercial capacitors wore compared
jvith those induced by the electron beam of a linear accelerator (LINAC) source. Dependence of the radioinduend current on applied voltage, geometry, dose, and dose-rate was
contrasted for Mylar, polystyrene, mica, tantalum, glass,
and ceramic capacitors. The effects were analyzed in
terms of models appropriate for the various capacitors, and
values of parameters defining those relations arc given.
The relative effectiveness of neutron and gamma radiation
In producing induced currents in these eapacitive elements
at the reactor environment was also obtained, (auth)
. - .fb /
TOTAL ELECTRO1T BACKSCATTERING AST) MCKEKISSION YIELDS
PROV 1,'ETALS BOKBARBED AT SEVERAL AIÍGLE3 BY 0.4 TO 1.4
KeV ELKCTR01TS
A.R.Frederickson, E.A.Burke
IEEE Transactions Nuol.Pii. 113-12, no. 6, 160(1972)
TotaH. high energy electron backscatter yields have been
measured for Al,Cu,Ta, at angles of 0°,15o,3Co,45°,60°,75°
from the surface normal. A nev7 experimental measuring
apparatus has been developed and tested to measure
total electron yield from irradiated materials. It
is relatively free from problems associated with
electron emission from the device itself.
44470
IONIZATION, SECONDARY EMISSION, AND COMPTON
CURRENTS AT GAMMA-IRRADIATED INTERFACES, Frederickson, A. R.; Burke, E. A. (Air Force Cambridge Research Labs.,
Bedford, Mass.). IEEE (Inst. Elec. Electron. Eng.), Trans. Nucl.
Soi.iNS-18: No. 6, 162-9(Dec 1971).
From Annual conference on nuclear and space radiation effects;
Durham, N. H. (20 Jul 1971). See CONF-710709.
Energy and charge transport by secondary electrons across
interfaces between gamma-irradiated materials can be important
for accurate predictions of radiation effects. In order to measure
these charge-transport effects, air ionization and secondary electron emission currents were observed in a multiple-cavtty aluminum chamber adjacent to tungsten and beryllium under s0Co y
radiation. It was found that low-energy secondary emission measurements are within 3% of air ionization measurements made in
the 6ame chamber and that both measurements agree with previously reported ionization measurements of energy deposition
profiles. Also, profiles obtained in relatively thin aluminum chambers (~20% of the maximum energy electron range), sandwiched
between different combinations of beryllium and tungsten, can be
accurately predicted from a linear superposition of single interface data. Finally, electric charge separation is observed at
gamma-irradiated boundaries even in the absence of applied electric fields. The sign and magnitude of the charge is found to depend upon the direction of the incident beam as well as the material combination. The change in electron current as a function of
the distance from the interface can be obtained from the data presented, (auth)
j
'
[
I
i
OIT THE CONDUCTIVITY PRODUCED III CdS CRYSTALS BY
R.Frerichs TIOli W I ™ <WWHA KAYS
Phys.Rev. £6^869(1949)
CdS crystals kept in the dark for a long time and then
exposed to a low density of excitation require a long
tame to develop their photoourrents. The photoourront
versus time curve tent sharply upwards. The same latent
period an often be observed aftera CdS crystal has had
a stror, exposure to infrared quenching radiation. This
«radiation activation "of the crystal is interpreted as a '
filling of traps.(But this concept must be competed
'
by the assumption
of
existence
of
two
tips
of
traps
and
1 eo B b e e
P
/UP
Í T S S " °* • . *? n»d e n^t « them.).Pap
f er reports also
:S1!
^^
**
and
RAMATIOIT I2OTCED ELECTRICAL E5TECTS III DIELECTRICS
}i.G.Pritz,D.J.Yentis
LMSC Rep?. (Lockheed Lissile Systems Division),Palo Alto
California
9
"ia,Au£rust 1966
"'
Discusses irradiation and space-charge induced breakdown
Gxl GC"CS *
5158
THERMALLY STIMULATED CONDUCTIVITY AND
LUMINESCENCE IN KBr DUE TO y IRRADIATION AT 10°K.
Fuchs, W.i Taylor, A. (Cornell Univ., Ithaca, N.Y.). Phys.
Rev., B; 2: 3393-3403(15 Oct 1970).
The annealing behavior of KBr, y-irradiated at 10°K, was studied by means of simultaneous measurements of the thermally stimulated conductivity and luminescence and of the optical absorption.
Over the investigated temperature range between 10 and 35°K, the
conductivity and luminescence behaved very similarly, and the
latter did not change its spectral distribution. AU observed peaks
have been ascribed to the annealing of the radioinduced Imperfectlons of the lattice structure. Four peaks, appearing at 14, 17, 20,
and 24°K with characteristic activation energies between 0.02S and
0.058 cV, which saturate in intensity after a moderate irradiation
dose, are believed to be due to the generation of conduction electrons. A smaller peak at 22°K, which was observed only In the
conductivity data, may be due to ionic motion. The most prominent
peak appeared at 27°K, and it was shown by "thermal cleaning"
experiments that this peak is caused by processes with activation
energies of 0.062 and 0.100 eV. Here, too, the signals are believed
to be causal by conduction electrons and their consecutive recombination with traps. The 0.062-eV process has "mixed-order"
kinetics, i.e., there is an excess of recombination centers. At
higher irradiation doses, the 0.100-eV process becomes dominant.
This process seems to be associated with the first annealing stage
of the H band, which had an activation energy of 0.097 eV. A tentative model of the H-center decay involves the dissociation of the
H center followed by an interstitial—vacancy recombination, (auth)
L.
•
ION DISPLACBMEHT CURRENTS III IRRADIATED ALKALI KALIDES
W.Puchs,A.Taylor
Phys.Status Sol. 38,771(1970)
it) •)
l/i
'
I
195
S?T
f
!•
j
I
U
I
RADIATION DAMAGE OF SHIELDING GLASS WINDOW
J.I'uruta, S .Okamoto
Ann.Rep.Had.C enter Osaka Prefecture 2^,70(1961)
A detailed analysis És presented. First a list of incidents is given. The damage is examined. If a ruptured
window is irradiated again by gamma rays from Co D O ,
numerous new light flashes are observed the frequency
of which decreased however with irradiation time. It
is believed that the the gamma irradiation charges
up the areas around existing fracture cracks,eventually
a high potential is reached and a discharge ensues. The
conductivity of the shielding glass was measured.lt
was found to be nearly independent of dose rate
and the ususual l/tn decay law for the current was
observed, n being about 0.6.
in A
DISCHARGE FIGURES IK DIELECTRICS BY 31HCTH01Í IRRADIATION
Ann.Rept.Radiation Center Osaka Prefect. 3.,82(l962)
I"O
Report refers to a study of the formation characteristics
of the discharge pattern in methylmethacrylate polyner.
The size of the resulting £±Ek±EidjEi:gx£ discharge pattern
depends on the total dose; Kihe pattern can be controlled by
the depth of the indentation msifcK obtained by pricking the
surface prior to irradiation and subsequent discharge,
,
OAMKA-RAY DETECTOR USING INSULATING MATERIALS
J.Puruta,S.Hiraoka,S.Okamoto,T.Kanazawa
Ann.Report Rad.Center Osaka Prefecture 3 . , ( l $ > )
• |
!
j
t
j
i
f"
i
i
I
DISCHARGE FIGURES IN DIELECTRICS BY ELECTRON IRRADIATION(II)
J.Furuta,E.Hiraoka,S.0kamoto,T50hnishi,Y.Tsujii
Ann.Report Rad.Center O^aka Prefecture 4.»77(1963)
Paper reports results Concerning charge decay,change of
electrical conductivity, and after-effects in insulators
irradiated by a 15 MeV LINAC. The method of triggered
discharge was used. The stored charge was measured with
a photocell receiving the scattered light from the discharge pattern, it having been found that the extension of
the pattern is proportional to the residual charge.
!
Ij é>
/97
'
)
i j
j j
( j
• i
'. !
I i
j I
• |
:
GAMMA RAY INDUCiiD CONDUCTIVITY IN INSULATING POLYMERS
J.Furuta,E.Hiraoka
Ann.Rep.Racl.Center Osaka Prefecture 5_,8o(l964)
Currents were measi'red for various linear polymers, at room
temperature.Polyethylene and teflon showed the highest
current values.During irradiation currents generally were
found to increase slowly with time, dose rate being constant
and equal to 3 200 R/h from a Co^° source. Compton currents
were; eliminated by a sandwich arrangement similar to
Meyer's. When irradiation was discontinucid, a fast initial
current decrease was observed,followed by a slow further
decrease. An analysis toy exponentials was attempted.
fag
GAMMA RAY DETJ3CT0R USING INSULATING MATERIALS (II)
J.Furuta,E.Hiraoka,T.Ohnishi
Ann.Rep.Rad.Center Osaka Prefecture 3_ 85(1964)
Measurements with a PMMA scatterer are reported, a) Integrated dose was determined by observing the voltage rise.
With doses between 0 and 6 000 R voltage increase was linear,
dose rates being between 9 and 120 R/iain and final voltages
up to 250 V. b) Directional dependence was determined
for a planar and a spherical detector, c) The energy dependence was measured between the energy of Co ° rays and
15 MeV given by a LINAC-For this purpose a de+ector with a
7 cm lead absorbed and 2.5 cr.i thick scatterer wae used.
jqQ
'
j
[
When the target current of the
LINAC is constant,the bremsstrahlung intensity in the forward direction increases as the third power of the energy. Sue
a relation was observed with the detector,showing lhat the
energy response is flat. Comparison with a Victoreen ioniatior
chamber showed the latter to be with a lower increase due tq
P"
)
1
1-
saturation deficit, d) Measurements with a liquid scatterer 1
were taken» The liquid contained in a plastic container
and. its thickness was varied between 0 and 70 mm. Hater with ,
10^ to 107 and salt solutions with 5 0hro-cm specific
resistance were used. The resistance had little effect*
,
GAMMA-RAY INDUCED CONDUCTIVITY IN INSULATING POLYMERS(II) V
J.Furuta,E.Hiraoka,S.Okamoto
'
Ann.Rep.Rad.Center Osaka Prefecture 61,83(1965)
{
fl
2.DD
DISCHARGE FIGURUS IN DIELECTRICS BY ELECTRON IRRADIATION
J.Furuta,.E.Hiraoka,S.Okamoto
'
J.Appl.Phys. ^1,1873(1966)
Brakdown discharge of different shielding window glasses
were investigated. The relation between radiation dose and
size fo discharge figure and the decay of the discharge
pattern after irradiation were studied. Relaxation times
very widely different for glasses of different corapostion
varyingfeisiwKKHbetween approximately haltff an hour and
nearly 100 hours.
(
i
I
!
GAMMA RAY DETECTOR USING IHSULATIHG MATERIALS(ill)
LIQUID SCATT3RER
J.Furuta,E.Hiraoka,T.Ohnishi
Ann.Rep.Osaka Prefecture 2>65(l966)
Measurements are reported with a liquid scatterer placed inside a plastic container between top electrode and measuring
electrode. Results are independent of the conductivity of the
liquid (water,ethyl alcohol,saline solutions,glycerinJ.Curron
if, varies with density of the scatterer ,decreasing slightly
with increasing density. The method can be used to measure
simultaneously the total doe if the liquid is a Fricke solution so that the system is equivalent to a Fricke dosemeter. In this case a flow method might be used where
the scatterer is connected w±x by tubings to an outside
system.
FAST NEUTRON DETECTOR USING INSULATING MATERIALS.I
J.Furuta,E.Hiraaka,T.Ohnishi
AnnuyRep.Rariiat.Center
Osaka Prcfekt.
8f100(1967)
Recoil protons from a. plastic
scatterer
are detected
_5^6xlO_j^, 2.6x10-!9, 3x10-19 A/neutron/min for the
neutrons Tram x (d,ny%Wé^TF(W,n) ^Be,
9Be(d,n)J-^B
GAt-iMA RAY IlíDUCED C02ÍDUCTIVITY IN IIISULATIiTG
POLYMERS(III)
J.Pur\ita,E.Hiraoka,S.Okamoto
Annual Rep.Radiation Center Osaka Prefecture £J,,95(1967)
Z"«<
j
L-
F~
10247
COMPARISON OF THE EXTRAPOLATED RANGES OF
ACCELERATED ELECTRONS IN WATER AND POLYSTYRENE,
Garsou, J. (Univ., Liege). J. Hadiol., Eleotrol., Med. Nucl.;
52: No. 10, 60G-7(Oct 1971). (In French).
Polystyrene can replace the water used in photographic dosimetry along the axis of a 10- to 34-MeV electron beam from a
betatron; In this way the extrapolated ranges of the electrons
may be determined. (France)
li
1 (\ IT
JLvO
ABSOLUTE CALIBRATION OP A COBALT-ôO GAkiià RAY BEAM
Radiology 65_, 394(1955)
íe polarity effect due to
Considerations about the
forward scattered Compton electrons.
22626
IRRADIATION OF SYNTHETIC DIAMONDS WITH
FAST ELECTRONS. Gerasimenko, N. N.i Lezheiko, L. V.:
Lltvin, Yu. A.; Smlrnov, L. S. (Inst. of Semiconductor Physics,
Novosibirsk, USSR). Sov. Phys.-Semiooiid. (Engl. Transi.); 4:
905-8(Dec 1970).
Translated from Fiz. Tekh. Poluprov.; 4: 1064-8(Jun 1970).
An investigation was made of the Influence of irradiation with
3.5-MeV electrons and of heat treatment on the electrical and optical properties (temperature dependence of electrical conductivity
and eathodolumineseence spectra) of synthetic diamonds. The
irradiation and heat treatment (800*C) altered the luminescence
spectra of synthetic diamonds doped with various elements In the
3000- to 10,000-A range. Irrespective of the nature of the dopant,
the spectra which were originally different In various details became similar to the luminescence spectra of irradiated and annealcd natural diamonds. The resistivity of semiconducting crystals was Increased by irradiation to various degrees depending on
the amount of the dopant present (the increase was greater for
crystals containing fewer dopant Impurities). It was found that
annealing at SOO'C after irradiation enhanced those changes in the
luminescence spectra which were due to Irradiation but such heat
treatment reduced appreciably the radiation-induced changes in
the resistivity. It was concluded that the changes in the luminescence, observed after irradiation with fast electrons, were due to
the formation of stable complexes, in which nitrogen atoms took
part, and that the changes in the resistivity were due to the generation of simple defects or of unstable complexes, (auth)
I
1
PERSISTED INT3HNAL POLARIZATION OF IKSÜLATORS P^CDUCSD
BY ELECTROlí B0LEBARDI52NT
. r^ n
D.J.Gibbons
Nature 128,177(1963)
Measurements on 0.3 and 1 micron
t h l ^ Í J K
between 0.1 micron thick metal (Al) c o n t a c t s show
a) t n e e x t e r n a l l y measured charge during d e p o l a r i z a t i o n
might g r e a t l y exceed the char fí e i n c i d e n t from from the
:
voltage was applied.
_
2 Of
t
TRANSIENT PIIOTOCUBRENT FOR FIKLD-DEPENDEOT MOBILITIES
Vf.D.Gill, K.K.Kanazawa
J.Appl.Phys. 43,52^(1972)
Tvro specific electric field dependencies, a simple poirer
law, a.nd an exponential dependence on the square root
of the field have been discussed. For the exponential
dependence, which is of current E Z X experimental interest,
step-function and pulse-illumination are treated, liesults
show that the pulse shape is insensitive to the functional
form of the nobility.For drift mobilities increasing ~.rith
the field, the transit tine decreases but reaches a lower
limit for high fields.The i.ui£ nitude of the pultjo docs depend
on the functional form of the mobility .Drift nobilit;.'
increasing iritb, the field resulta in decreasing current
flow.Velooity saturation occurs at hi^h fields.
RADIATION EFFECTS (DN GLASS:AN ANNOTATED BIBLIOGRAPHY
**
B.A.Oillmore,',V.F.Heenan REIC-KEMO-26
(Radiation Effects Information Center,Battelle Memorial
Institute,Columbus,Ohio)Sept.15,1965 .Contract AF 33(615)1124. 31 p . «.050
ReiCHBHO-26
About 150 abstracts on glass,glass devices,and dosimeters.
* nn
1
210
D.D.Glc.ver,D.L.Hester
Transactions American Nuclear Society Vol.8,No.1,p.66(1965)
,- •»
A poled ferroelectric is used for measurement of steady
state gamma dose rates,The current density is found to be
f
proportional to dose rate.With a dose rate of 245 rad(HgO)/sec
i
2
the constant of proportionality is 1 1 10~^ /rad/sec.
A
1
polarization effect is observed: 7/ithin the first couple of
!
minutes the current decreases to about 305» of its initial
i
value,subsequently remains constant.On short-circuiting
[
a discharge transient analogous to the charging transient
I
is found.
t
•
042766
Gorbachev, V.M.; Uvarov, N.A.; Gurov, G.A.;
Kudrya, V.N. The effect of pulsed irradiation on
polyethylene coaxial cable. (In Russian). Reakisiya
koaksial'nogo kabclya s poliehtilenovym napolneniem na
impul'snoe obluchenic. At. Ehaerg. (Jui 1972). v. 33(1)
p. 576. Deposited article; for English translation see the
journal Sov. J. At. Energy.
coaxial cables; gamma radiation: mev range 01-10; neutron
density; neutrons; photons; polarization; polycthylenes;
pulsed irradiation; radiation effects.
\
^ ^ ^
"
i l l
•*•'*•
I SELF CHARGING KUCLSAR BATTEST'
/ U.S.Patent 3 200 269(1965)
" Vi.Goldstein,II.C.Lieb,
Describes a Sr^° battery.
I THE ELECTRET EFFECT IN PARAFFIN WAX.
« Gomulkiewicz, J .
Phys. Stotus solid! (Germany) 3, 276 (1963)
Measurements are reported in which samples of pure paraffin wax were irradiated with
beta rays from a 25 me Sr°O source ond subsequently polarized by application of a consent
voltage. Currents and surface charges are measured. In addition to absorption effnef:
heterocharges are obtained for fields up to 2000 V/cm and homocharges for higher field?.
The charges decay, however, within a maximum of 30 days.
/
'
~'
I
OS THE RÀUIOELECTRET EFFECT IN PARAFFIN WAX
J.Gomulkievica
.
Aota Phys.Polon. 30,349(1966)
Describes preparation of eloctrets from beta-irradiated
wax.
!
ON THE 1ÍATUKE OF HADIOKLBCTHBT EFFECT IN PARAFFIlt WAX
J.Gomulkiewicz
Aota Phys.Polon. 31.,575(1967)
The effect is interpreted in terras of trappinc of
electrons. The theory gives a model for the phenomena
responsible for the production of free electrons and
their confinement in traps.
»
I
p
i
12103
(AD-743838) THIN-FOIL CALORIMETERS FOR THE
MEASUREMENT OF ENERGY DEPOSITION PROFILES AND SPATIAL FLUENCE DISTRIBUTIONS OF LOW-ENERGY PULSED
ELECTRON BEAMS. Graven, W. M.; Burns, W. C.s Peterson,
H. V. (Aerospace Corp., El Segundo, Calif.). 23 Mar 1972.
Contract F04701-71-C-0172. 37p. (SAMSO-TR-72-109). NTIS.
A thin-foil calorimeter designed to measure energy deposition
profiles for electrons with ranges less than 100 micrometers has
been tested with two pulsed electron beams. In addition to the diagnostic determination of the beam spectra obtained from the measured deposition profiles, the spatial fluence patterns of the beams
have been measured with a total-stopping calorimeter array. The
calorimeters are capable of operation over a dose range of a few
kllorads to nearly 100 Mrad. Fluence measurements with the
calorimeters can be made accurately with the error probably not
exceeding 2 percent. In contrast, the dose-path measurements are
less accurate although the probable error has not been determined,
(auth)
;
;
1 I~T
ÁI /
-
;
|
j
{
;
i
25267
lONl'MTlON CUHHENTS IN LIQUID ION1ZATION
ClIAMBliliS: LOW CONDUCTIVITY LIQUIDS. Gregg, li. C.i
Balcale, G. (disc Western ({«nerve Univ., Cleveland). Contract W-S1-10S-1SNG-78. liuillat. Hcs.j -IS: 13-33(Apr 1970).
Win", an I<m cluunlier cui:t:iinlnE a low conductivity liquid Is
exposed to a very short pulse of ionizing radiation (••'10"' sccuiiclfi),
the current in the- external circuit la hifih during flic pulse and ,
•'
then falls t'apidly and noncNpunenUully towards 7.ero. Kurther,'
the shape of the curve depends on both the delivered dose and it
the collecting field. A theoretical analysis of the liquid ion chamber under these conditionü is given qunnlitating the effect of space
charge and deriving expressions relating the observed current
to tlii' tundarorntnl physical properties of the liquid. Experimental data for n-hcxane are aliio shown covering six decades of both
time and current for various collecting fields and Incident doses
fur which data essentially establish the theoretical treatment.
Onc-MrV electron beam Irrudlitliunii were used ranging from 0.8
to 120 niA in pulse lengths from I0~8 to 10"° second. Besides
valued for the recombination coefficient and other parameters,
evidence Is given of Ionic charge multiplicity and tree unattached
electrons during the initial Btaftcs of the process, (auth)
027320 Grill, M. (European Atomic Energy Community,
Ispra (Italy). Joint Nuclear Research Center).
Commission of lhe European Communities, Brussels
(Belgium). Collection!, seK-pomtcKMl neutron flux
deleilnrs. Part 1: Theoretical considerations.
EUR—4775(Pl.l). Mar 1972. 38 p. 6 figs.
beta panicles; calibration; currents; emission; errors;
neutron tfclcclibn: neutron flux; performance.
30093
ELECTKIC DISCHARGE IN RADIOACTIVE DIELECTRICS. Gromov, V. V.j Surikov, V. V. At. Energ. (USSR);
32: No. 2, 172-3(Fcb 1972). (In Hussian).
When samples containing radioactive isotopes aro placed in a
conducting medium, (e.i;., ionized air), accumulated charges may
be neutralized by current carrlors in the surrounding medium.
Experiments were conducted with samples of glass containing 30
mCi M Sr (in equilibrium with 90Y) per gram of glass. A large
electric charge was accumulated within the poorly conducting
glass, and eventually led to a mlerorupture of the surface layers
of the glass by discharge. (2 figures) (K.S.W.)
1*
220
ELECTRON IRRADIATION OF GLASS DISKS.
Gross, B., Sobral, M .
An. Acod. Brasil. G e n e , 28, no. 2, II (1956)
221
Short report or, charge storage effects in electron irradiated borosilicate glass.
IRRADIATION EFFECTS IN BOROSILICATE GLASS.
Gross, B.
\
Phys. Rev., 107, 368(1957)
Samples of borosilicate glass ore irradiated with high energy (2MeV) electrons, the range
of which is smaller than the thickness of the sample. Irradiation introduces space charges
in the dielectric by electron trapping. The charge distribution is investigated by method
of thermal release. During heating charges (by the induction plats method) and shortcircuit currents are measured. Toobtain more detailed information on the spatial distribution,
a sectioning method is used which allows to determine by thermal release charges contained in different sections of the original sample. It is found that the trapped electrons
build up a layer of negative charge; in addition a positive compensation charge is found.
Heating releases electrons from traps and increases the conductivity of the glass matrix.
Discharge occurs by migration of tha electrons to the nearest electrode under the influence of the internal space charge field.
112
25267
IONIZA TION CUJWENTS IN LIQUID ION1ZAT10N
CIIAMBEHS: LOW CONDUCTIVITY LIQUIDS. Gregg, li. C.;
Bakale, G. (Case Western Itcscrvc Univ., Cleveland). Contract W-U-lOO-EtCU-te. ludlat. UeB.j 4?.: 1S-33(AIW 1970).
When an ion chamber containing a low conductivity liquid is
exposed to o very short pulse of ionizing radiation (~10"! seconds),
ihe current in the external circuit is high during the pulse and ,
•
then .falls rapidly and nonexponentially towards zero, rurlher,'
the s/hape of the curve depends on both the delivered dose and .,
the collecting Held. A theoretical analysis of the liquid ion chamber under these conditions is given quanlitating tlie ctfect of «pace
charge and deriving expressions relating the observed current
to the fundamental physical properties of tlio liquid. Kxpcrimental data for n-hexiinc are alao uhown covering six deendes of both
time, and current (or various collecting fields and incident doses
for which data essentially establish lhe theoretical treatment.
Onc-McV electron beam Irradiaiions were used ranging from 0.8
to 120 mA In pulse lengths from 10"' to 10"8 second. liesiden
values for the recombination coefficient and other parameters,
evidence Is given of ionic charge multiplicity and free unattached
electrons during the initial stages of the process, (autb)
027320 Grin, M. (liuropcan Atomic Energy Community,
Ispra (Italy). Joint Nuclear Rcieatch Center).
Commission of the European Communities, Brussels
(Belgium). Collcclrolis, scll-putvdcrcd neutron flux
(tctcclors. Part 1: Thcoreiiixl considerations.
KUR--4775(1*1.1). Mar 1ÍI72. 3S p. 6 figs.
Octa pari/cícs; cnlibrMion; currents; emission; errors;
neutron detection:
neutron flux;
2l°f
performance.
30093
ELECTRIC DISCHARGE IN RADIOACTIVE DIELECTRICS. Grotnov, V. V.; Surikov, V. V. At. Energ. (USSIl);
32: No. 2, 172-3(Feb 197Z). (In Itusslan).
When samples containing radioactive Isotopes arc placed In a
conducting medium, (e.g., Ionized air), accumulated charges may
be neutralized by current carriers in the surrounding medium.
Experiments wore conducted with samples oi glass containing 30
mCl " S r (in equilibrium with l»Y) per gram of glass. A large
electric charge was accumulated within the poorly conducting
glass, and eventually led to a microrupture of the surface layers
of the glass by discharge. (2 figures) (K.S.W.)
i'1
220
ELECTRON IRRADIATION OF GLASS DISKS.
Gross, B., Sobral, M .
An. Acad. Brasil. G e n e , 28, no. 2 , II (1956)
221
Short report CR charge storage effects In electron irradiated borosilicate glass.
IRRADIATION EFFECTS I N BOROSILICATE GLASS.
Gross, B.
Phys. Rev., 107, 368(1957)
\
Samples of borosilicate glass ore irradiated with high energy (2MeV) electrons, the range
of v/hich is smaller than the thickness of the sample. Irradiation introduces space charges
in the dielectric by electron trapping. The charge distribution is investigated by method
of thermal release. During heating chorges (by the induction plate method) and shortcircuit currents are measured. To obtain more detailed information on the spatial distribution,
a sectioning method is used which allows to determine by thermal release charges contained in different sections of the original sample. It is found that tho trapped electrons
build up a layer of negative charge; in addition a positive compensation charge i i found.
Hooting releases electrons from traps and increases the conductivity of the gloss matrix.
Discharge occurs by migration of ths electrons to the nearest electrode under the i n fluence of the internal space charge field.
-222
JRRADIATION EFFECTS IN P1.EXIGLAS.
.bross, B.
/ J . Polymer Sci., 27, 135 (1958)
Samples of methyl methacrylate arc irradiated v/ith 2 MeV electrons. Stopping ond
trapping of I ho incident electron! in the dielectric loads to the formation of o negative
space charge. Under proper conditions, i . e . sufficiently high irradiation, tha electric
field of this ciiuryo can produce breakdown accompanied by the cppcarcr.ee of ci
characteristic discharge pattern. The nature of the effect ond mechanism of the breakdov/n is discussed. It is shown that the bulk of the space charge is concentrate;! in a
narrow layer at a depth corresponding to the effective range of the electron beam. The
quantity of charge released during breakdown is measured for various doses and compared
v/ith the value of the intercepted charge. Breakdown is induced by pressing a pointed
electrode to the: dielectric surface. Tho clcclrodo is connected to a capacitive measuring
device. Storage efficiencies of up to 40$arc found; charge leakage at room temperature
is high so that breakdown can be induced only v/ithin a few minutes after irradiation.
22
ARRANGEMENT FOR THE MEASUREMENT OF PENETRATING ROENTGEN- AND
GAMMA RAYS.
Gross, B.
German Patent 1 107 350. (1959)
3
22 A
tH-saibsr. a device in which the Complon current or the voltages produced by the
o'.'iorption of radiation in insulators are used for radiation ciosimetry. It contains a
I'-ullou'.,, a measuring electrode connected with an electromelric measuring system, and
u
grounded top electrode. The top electrode might be a conducting paint applied to the
icültorer. Tho measuring electrode is of metal; it must be thick enough !o absorb most of
•lie incoming photon radiation to avoid a back-component of current and it must he
completely covered by tho õcallerer to avoid charge leakage through the ionized air.
me stutterer is made of a highly insulating and radiation resisting dielectric; its thickness
"•«si bo several times the average electron range to avoid bockscoltering effects at the
too surface of the metallic measuring electrode. The photon flux in the scotterer produces
a Compton current carried by the secondary Compton electrons moving preferentially in
the direction of the primary photon boom. The current is proportional to doie rate and
by suitable dimensioning of the measuring electrode can be made largely independent of
ci:ergy. The system might operate also in open-circuit, tho voltage of tho measuring
electrode after a given time being proportional to the doso.
- <
j THERMOVOLTAIC EFFECT IN GAMMA-IRRADIATED BOROSILICATE GLASS.
Gross, B.
,
Phys. Rev., ]K>, 337(1958)
22O
Borcsiliccte glass was irradiated with a high dose of gamma rays from a Co"" source.
After irradiation the glass was heated while a temperature gradient was maintained
betv/een its surfaces. During the heating an external current was observed. The direction
of the current in the dielectric corresponded to a transport of negative charge to the
electrode with the higher temperature. The observation of open-circuit voltages of up to
10 V excludes a thermoelectric effect. Heating to 400°C produces complete annealing
|
j
j
\
THE COMPTON CURRENT.
Gross, B.
Z . Phys., 155, 479 (1959)
.
Tho secondary electrons produced by penetrating X-rays and gamma rays move
preferentially in the foreword direction. In an insulator absorption of the photon beam
is therefore accompanied by an electron current. This can be measured by a suitable
receiver that collects tho electrons and absorbs the photons. An approximate expression
for the Compton current is established. Results of measurements ore found in satisfactory
agreement v/ith theory.
'•
•
22b
CHARGE DISTRIBUTION AND RANGE EFFECTS PRODUCED OY 3 - MEV ELECTRONS
IN PLF.XIGLAS AND ALUMINUM.
"
Gross, B., Wright, K.A.
Phys. Rev., 1_M, 725(1959)
j Charge distribution curves of nearly parallel beams of monoenergefic electrons of 3 MoV
are measured in plexiglas and aluminum by a method in which an isolated "catcher"
connected to an elecrromctric charye measuring system is sandwiched between different
thicknesses of absorber. The charge distribution in depth reaches a maximum at approxirnotsly 2/3 of maximum electron range, Tho maximum in plexiglus is sharper than in
aluminum. Results confirm the existence of a spcico charge layer in dielectrics after
electron bombardment. The measured charge distribution reflects the differential rango
dislribulion of monoenergetic electrons.
221
j
i BETA PARTICLE TRANSMISSION CURRENTS I N SOLID DIELECTRICS.
Gross, B., Bradley, A . , Pinkerton, A . P .
J . oppl. Phys., 3 1 , 1035 (I960)
.
9 26
A A
Short-circuit currents are calculated for a device in which a particle source, v/Sich
constitutes one electrode, is separated from a counter electrode by dielectrics of varying
thickness. Particles which do not reach the counter electrode contribute to the current
due to induction. Thus the total current contains a transmission and an induction (displacement) component. Theoretical results are in close agreement with experimental
results. It is shown that the current versus thickness characteristics can be used for o
detennination of beta absorption curves.
SOLID STATE NEUTRON-GAMMA DOSIMETER.
Gross, B., Murphy, P.V.
j n Selected topics in radiation dosimetry; proceedings of a symposium, Vienna, I960.
Vienna, International Atomic Energy Agency, 1961. p. 549.
A direct flux of gamma rays produces in an insulating scotterer a Compton electron
current, the intensity of which is proportional to the radiation flux. Similarly a directed
flux of neutrons produces in a hydrogenatcd insulating substance a current of recoil
proton; which is a measure of the neutron flux. A device can be constructed which
combines both effects in such a way that it differentiates between neutrons and photons
in a gamma-neutron field. The construction of such on instrument and results of measurements are reported.
STORAGE AND LIBERATION OF ELECTRIC CHARGE I N IRRADIATED DIELECTRICS.
Gross, B., Murphy, P.V., Costo Ribeiro, S., Milanez, F.
A n . Acad. Brasil. G e n e , 33, no.2, IV (19Ó1)
|
i
Samples of quartz and polystyrene were irradiated with hiah energy electrons a) from a
Von de Graaff machine (2 MeV) and b) from a 5 curie Sr™ source. Doses varied between
5 and 15 Mr for the Sr irradiction and 80 Mr for the Van de Graaff. After irradiation
samples were irradiated with the ultraviobt light of a Hanau quartz lamp. During and
after irradiation current and charge release were measured. It was found that ultraviolet light produced charge release. The bulk of the released charge was measured
during the first minutes of irradiation. But while the electronic chorga actucilly absorbed
in the samples was of the order of 10~4 coul, lhe released charge was of the order of
10~8 coul, giving an efficiency of the process of only a tenth of one promile.
,
«•
ELECTRICAL IRRADIATION EFFECTS I N SOLID DIELECTRICS.
Gross, B., Murphy, P.V.
Nukioonik, 2, 279 (1961)
Review article dealing with space charge and current effects induced by particle and
gamma .rrad.afion. Contents: Electrical breakdown induced by electron bombardment
Charge storage in borosUicote glass. Differential range distribution of monoenergetic '
electrons. Bete. particle transmission cur.onts in solid dielectrics. Thermovoltaic effect
in gammg-irraaiated borosilicate glass. Gamma-powered defectors and power sources
Current production by neutrons and neutron dosimetry.
f
2 3/
COMPTON DOSIMETLR FOR MEASUREMENT OF PENETRATING X-RAYS AND GAMMA
RAYS.
Gross, B.
Radiolion Research, 14, 117 (1961)
An unidirectional beom of photons produces in an insulator a current in the absence of on
external electric field. This allows construction of a gamma foy battery which might
cperale in short-circuit or in open-circuit. A detailed calculation of current and voltage
wiriut as a function of dose rate and dose is given. It takes into account directional
tonsiiivity, effects of dimensions, and energy dependence. It is shown ho// backicolleriiif) can be minimized by using us top section of ths measuring electrode a so-called <
"solid Faraday cage".
J
i
I
CURRENTS FROM GAMMAS MAKE DETECTORS AND BATTERIES.
Gross, B., Murphy, P.V.
Nucleonics. 19, 86 (1961)
I
i
23$
Paper describes the production of currents and voltages in systems containing solid d i electrics under the effect of gamma irradiation.
•- . ,
G A M M A IRRADIATION EFFECTS O N ELECTRETS.
Gross, B., De Moraes, R.J.
„
Phys.Rev. 126,930(1962)
\
•
'
'
Samples of Carr.auba \!sx (2 cm height) were polarised at 73°C
by applocation of a voltage of 14 keV.After
' ..._
polarisation, cooling,and short-circuiting they were irradiated synaeti-ioally in a C o 6 0 facilitjjiith doses :
up to 5 MR. 'íiioy vrore then kept in shprt-circiiit
for 2
nonth. Subae<iucntly the polarisation wes determined by
heating in short-circuit to 74°C . The released charge,
ana therefore the polarization, i-rere found to decrease
approxiuately cKponontially ifith a decay constant of 1 1-2.
Thus elcctrots are depolarized by gamma rays, this being
a volume effect.
234
7
r
!
;
j
,
j•
'• .-.
f
1.5ÜTH0D AND APARATUS POIi MEASURING THE DOSAGE OP X-HAYS AND
|
GAW5A-2ays
B.Grons
Z3S~
US.Patent 3 122 640, Feb.25,1964
CHARGE STORAGE EFFECTS IK SOLID DIELECTRICS
B.Gross
Elsevier Publishing Co.,Amsterdam,.I964
?
••
OIL
Bibliographical review on the ©lectrot and related effects,
i
I
GAKfA-liADTATTOM INDUCED CURRENTS IN TE?LON.
Bernhard GroBo (international Atomic Energy Agency, Vienna) •
2 37
Kukleonik, 6?2O-3 (Feb.:I964)
Absorption of gamma radiation in dielectrics is accompanied
by a current (Compton curront) which is due to the forward
scattering of Cornpton electrons. Measurements of this current
are reported for radiation detectors with a teflon scatterer
and a teflon or lead absorber. Polarization and surface
effects were observed and radioinducod conductance was measured.
Wi-tli the help of a mathematical model the influence of conductance on short-circuit current and open-circuit voltage
.is discussed.
,
J
COMPTON CURRENT AND POLABIZATION IN GAMMA-IRRADIATED
DIELECTRICS
B.Grous
•
J.appl.Phys.36fl635(l965)
Attenuation of a directional flux of gamma radiation in a solid
dielectric is accompanied b y the production of Bompton current
and space-chargos. Under proper conditions the space-charge
field can be high enough tp produce breakdown.A phenomenological theory of these effects is developed,which is based
on Cornpton-cur.?<snt theory and experimental results of breakdowninduced charge release in glass.It takes into account spacecharge formation due to the trapping of high-energy Compton
electrons and persistent internal polarization associated with
the production of electron-hole pairs by low energy secondary
electrons.
2 Si
f
!
'
;
; .
; ,
\ ]
\ •
;
b2
B«ürosssV
J.Appl.Phys. jj8 , 2272(1967)
Bombardment of"high-resistivity solid dielectrics
leads to electron trapping and space-chur/je buildup. The space-charge field in the dielectric can
becorno high enough to reduce significantly the range
of the incident electrons» It has been conjectured
that the space-charge field in the dielectrics leads
to an internal potential drop v/hich might exceed the
accelerating potential of the electrons» A simple
mathematical model gix is developed which gives
a semiquantitative picture and confirms the possibility
of achieving within the dielectric potentials in excess of the electron potential. It is shown that
there is no contradiction with the principle of conservation of energy $ &a$txfek&fc the system transforms
the radiation energy (i«e.kinetic energy of the incident
electrons) into electric field energy.The efficiency of
the conversion is calculated as a function of the reduction of the electron range.
D2VICS FOR MSA3UR.IKG íliVRD X-Ray GâMMA RADIATION
___3..<3rO3S._...
„
_
SC-T-67-0944 (Translated for Sandia Corporation,
Albuquerque, Nev? Mexico, from German Patent 1,107,350
List of References , X Ü Ã X IA3* Vol.lo,No.2,13(1963).
H E SECI'IOITIIIG TECHITIQUB POH THB DBT33i:il!ATIü!T OF 0?KB
VOLUIJS P0L.',.iíI2ATIÜlí OP THE TliaiUlOELBCTitiir
B.Groso.
Ins Static Electrification. Inst.of Phys.
Conf.Serie3 Ho. ll,London 1971, p«33
Paper discusses the principle of the sectioning technique
for the determination of charge distribution in charced
and/or polarized dielectrics. It is shown that the
method allows to distinguish between dipole and
space charge polarization.
COI-V'i'OlT LIO'uJS'o
B.Ciroso
Detailed Ahooretiõal ana experimental investigation ,
dealing vrith the ciiuracteriuticsj of Coivpton Siodet! under
traiicient ana citation;.ry ooiidltions. A circuit model i s
doveloj-.od vrliiah allo-.ra to calculi.1^ tho transient response
and predicts occurrence of hi^h-frequcne;,' oscillation:;.
The davant&gos of i.\y:.)tei:ia liitii lov* internal resistance
aro diiscuascd. Er.poriueiitcs voro vorforued v;ith the Photon
radiation of an 1J LoV J3etr.;tron. The influence ofOooinotrical parameters (uiofjorhor tin ukne&z of center utid
front abaorber) and of alosorlinr Memorial 0:1 amplitude
end direction of tbc external c^iri-ent are stuiicd. -'he;,aro in ca tir;factor,y cijreoiiionk vàth the proãi ctionc of
24
ti'.e nodo] >
;
cuiuriii'iis irr U;.I;.ÍWÍ;Ü DI)ÜI<KC:':;ICS AI:D
Cl? ZLiíC-Pl^LJ) 1-L;L-.ÍJ3S
B. Or o c c, r. • P o r i Kan
J . Appl. Ihv s . _4 3_, oj 3 (197 2)
'iiiien a previously ci:u.r^cd d i e l e c t r i c i s cliort-oircuited,
diooliar-jo currents r e s u l t duo to the i.ioveiiont of charge
c a r r i e r c i n the f i e l d of tho Bi.aoe charge. I t i s tihoirn
for planc-i>arallol g-eoKetry, that tho diochargo current
i s givon by tiio prodvict of chr.rgo density a t , and
velocity of, the aero field plane, 'i'iio reaultin^; expression includes the dlcplaceunotit cvu^ütit. I t can
also be applied vhon the dielectric ÍB exposed to the
bean; of penetrating radiation, vhere i t e-llovs to
evaluate the effect of space charge on external current.
In this connection the behavior of Gouipton diodes i s
discussed.
CEAKOB BülIiü/üP III KhECTliOn-IIüUJJlAfSi) DIKLSCTIÍICS
t
33.Gross, J.3)o'ir,
Electrets,Charge Storage and Transport in Dielectrics.
ElectrochoDical Society,Meeting,Miami Florida,October 8-13.
Extended Abstracts, IÍ0.II5, p.296(1972)
Irradiation of dielectrics with non-penetrating electron
beams generates long-lasting space-charges. A simple
experimental and mathematical method is developed for tho
investigation of charge buildup during irradiation. Time
resolved charge measurements carried out frith pulsed beams
of monoenergetio electrons of 1 MeV energy,pulse duration «
of 4x10""-' sec, and and average current density of 10~ 2 A/cm
allow to analyse effects of oharge leakage oaused by radi
ation induced conductivity and of electron range reduction
oaused by retardation of the incident electrons in the
internal space-charge field. Leakage is found to pre dominate in Silica and Borosilicate Glass while range reduction predominates in Polyethylene.
243
Z44
6't
31S
Appl. Phys. Lett., Vol. 22, No. 7,1 April 1973
Charge diagnostics for electron-irradiated polymer foils
B. Gross, G.M. Sessler, and J.E. West
Hell laboratories, Murray Hill, New Jersey O7'J74
(Received 26 December 1972)
on both
both surfaces
surfaces aarc irradiated
Polymer foils enrryinj; thin vacuum-deposited electrodes on
casurcment of
ivllh nonponetratiiH! :nonocncrgotic electron beams of various energies. Mcs
ilic currents and charges drawn from both electrodes and of U>o voltage buildup between the
electrodes during and after irradiation allows one to determine charge storage parameters
of such electrets.
Bulletin of the American Physical Society
'March 1973, Series II, Vol. 18, No. 3 P.
GC 3
Charge Diagnostics for Electron-Irradiated
Polyrcer Foi1B. B, Gross, C. M. Sessler and J . E. Vest,
Bell iAborntorJes, Murray Hill, K. J.— Polyi.cl- foils of
18.5 and 25ufli thickness carrying thin vacuui.-depo3ited
electrodes on both surfaces arc- Irradiated with aono
energetic 10 to 50 kcV electron beams. Measurement of
the currents and charges drawn from both electrodes and
of the voltage buildup between the electrodes during
and after irradiation allow3 one to determine the mean
depth of charge deposition, the leakage resistance of
the irradiated volume of the f o i l , possible leakage
through the nonlrradiated volume, and breakdown conditions, a l l as a function of beam energy, incident
charge density and time during or after irradiation.
I t is also possible to recall charge deposited by the
beam in the f o i l . This i s achieved by irradiation of
the charged f o i l with short-circuited electrodes.
BUILDUP IK ELBOTHOli-IIuL'i.uJL 'iB'J) DISLSCTÜICS
Sj J . D O Ü )
S.Iiablo
. 44» 2459
(1973)
Irradiation of dielectrics with nonpenctratir.g electron beams generates long-lasting space charges. A
simple experimental and mathematical method is developed for lhe investigation of charge buildup
during irradiation. Time-resolved charge measurements carried out with pulsed beams of 1-MeV
electrons, pulse duration of 4 x 10~5 sec, and an average current density of 10~JA/cin2 were used to
analyze effects of charge leakage caused by radiation-induced conductivily and electron range
reduction caused by retardation of the incident electrons in the internal space-charge field. Leakage
is found to predominate in silica and borosilicate glass while range reduction predominates in
polyethylene.
/
l^M'LVHOJi 0? El.üOTliOH AV.-J-A'iiOiiUS 1)1 i,BAl;3 OF ELWO'iMfOSKTl
;:;:AÍÍ:;IIÍG OP I^ÜIÍLATIÍ.G FILL:?
^
ii.Groi.;skrcua .
Avalr/aoho elcctrom; arc collected on "thin insulating
folia covering the anode of a parallel plate capacitor.
Charco ir.iafiea aro developed by xerographic techniques.
The influence of foil thickness and developing tech.nio.ues
are stuilied. 'iiho minimum number of electrons which can
still be detected is 3x1O?.Images do not give direct
information on avalanche mechanism i;hen more than one
avalanche has occurred. An application of the nothod
for uea.'Aircirients of alpha particle traces is indicated.
;
•
1
Í
ELKOiVOSTATIC CHAif.GS ÜISTKIBUTIOIT Oil ULTRAHIGH VACUUM
CLLiivVJii) BILICA'fSS
J . J.Gi'oaisman
J.Vaommi S c i . T e c h n a l . ^ , 2 3 3 ( 1 9 6 9 )
DeBicn and fabrication of UHV systenns to measure
dioti-iljutione are described.
i
-
o0Lty
''
HA": TO'3 OV lu'i! EiKRGV iiLiiCi'Jiu^S iJTjJ I'Ool'FAQ'JS III Al
Hovorts weufjiire:-oiita in the cnoT^y ran^e 10 to 150 hcV,
^•iviiiü the r e l a t i o n
, 7
It, =- 773 B '
for E in keV,ll i n nc/cr.^
vrhere H i s the uaxir.iuw range.
15V
G^I^ATIC 1 !; CP
i.;L:j;crauiTY BY R/.BICACTIV:; .VASTAS
a, C, Gumuc i on. J.0'1.1 2J ckri s
US Patent 3 250 925 (lp65)
Tlio ijys^PiH pji'ploysa a pc.ii' of juxtaposed olootro'los; j.^ir
into c.;.{"c-ívjè'JJro3yte contair.inj ráSi o elements emiiiiJt'e
rj^:ii,l'ota and gan:i::« r a d i a t i o n . SkE-ô^áyrafsifesxEiai:
Tu the electrolyte a gradient of radioactivity is imposed
by a shielding arrangornent«
*
IIÍD1V1DUAL DOSEI 33TER POR R.VUIOACTIVE A1TD OTHER
j
i
j
j
Í
P.S.Gxiponov,0.A.2^/azdrikov,U.V.SinãelnikoT
USSH Patent 115 132(1559)
The docreaoe of the surface charge of an electret after
irradiation "by gamma rays is used as a neasurenent for
exposure dose. A device is described.
2,57
/
/
ELKCTRICAL CONDUCTIVITY OP G/JJU-IRRADlATIiD KOÍIOJ-ÍÜ1Í3
AT LO'.i TKKPURATURE
K.lIadoi,Y.Tubatu,K.Oshima
J.Phj-s.CheBi.2i,3S62(l97o)
THJiORY A3?J) APPLICATION OP TIIBIikalLY STIMULATED CUHREiiTS
IN PHCTOCOlíDUCTOiíS
B.H.Haoring, U.K.Adams
l'hyo.Hev. 112,451(i960)
The paper diecucsea the proporties of a band i,;oti.cl with
localised stateo in the band gap for the two extreme
oases of fast re trapping and slow
I
i
PIICTOSiHSSIOIT FiiOL" POLYMERS
F. V.ai, 1 •.. J . I'ornatei n
IBB3 Transactions ! : S - l 8 , 1 7 0 ( l ? 7 l ) Ho 6
r h o t o e n i s c i o n fror.i pol;.ucr?»,including polyethj-lciv.;,]:apton,
t e f l o n , and PVC i r r a d i a t e d b.v 15-23 I'-eV ;v]>f'otop.s liae boon
rnado.K-.iiBCicn i u t e r . s i t i o s \;QTO conparcd to ti:ooe i'vov. c e vfiral oor.ilv.otorujranci'-io fron oarbon to t:.!it:iliun,a:;:!. from
other ir.f;ulators,cxtch i_s {jlar;s; and r.ica.i'or r.ll !..::iorials,
iho r e l a t i v e emission i n t e n s i t y vrr.o fonr.d to be ir.aii nly
p r o p o r t i o n a l to the p h o t o e l e c t r i c absori-tion o o e f f i c i o n t .
Under the pulsed i r r a d i a t i o n , the i n s u l a t o r s onit+ed
ao conductorc vrhen backed by conducting «hects but exhibited
reduced enifsaion a s s o c i a t e d «:ith trapped charges vlion
i isolated.
RADIATION L'F'?i;CTS ON CAPACITORS Al?D DISLBCTillO
Donald J. Harwaan (Battelle Memorial Inst., Coltuabus, Ohi").
p«553-60 of "Institute of 3nvir«rr.iental Sciences, 1^63 Annual
Technical Westing Proceedings." lit. Prospect, 111., Institute
of Environmental Sciences, 1963»
-
2.S5"
Transient and permanent radiation effects on organic and
inorganic electrical insulation materials are discussed. Hadiation effects on capacitor dielectrics of glass and vitreous
enamel, mica, ceramics, paper, plastics, and electrolytes are
discussed. 19 references. ( R.S.U.)
1109
(N-fi9-3323C) ' EFFECT OF RADIATION ON ELECTRICAL INSULATING MATERIALS. Hanks, C. L.; Hamman, U. J .
(Battelle Memorial Inst., Columbus, Ohio. Radiation Effects Information Center). Juno 16, 1969. Contract NASw-1568. 59p.
<NASA-CR-101129; HEIC-46). CFSTI.
? Information available on the effects of steady-state radiation on
electrical insulating materials are compiled and summarized. The
insulating materials are classified as organic or inorganic with
separate sections on bull; type specimens (film, sheet, etc.), wire
and cable insulation, encapsulating compounds, and connectors and
terminals. It is the Intent of the report to provide information for
broad estimates of the effect of radiation on various insulating
materials and is meant to be used us a guide in the early design
stages. Detailed information as required In the terminal stages of
design Bliould be requested when detail!) of all environmental conditions, radiation exposure rate, and total dose are known, (auth)
(STAR)
1/
f
'
q ir L
« •/P
'3202
THERMALLY STIMULATED CONDUCTIVITY OF 1R«AD1ATKD ALKALI IIALIDKS. llanlcy, Peter Itoiuld. Ithaca,
N. V.; Cornell Univ. (1908). 170p. University Microfilms Order
No. 70-6967.
"ZÕ~l
'
Tilt! SÍS.
Thermally stimulated conduetivity (TSC) that is attributed to
tlio release of charge from electronic and ionic defects during
thermnl annealing of single crystals of KBr and NaCl was examiiu'd. A '"Co gamma source, or a monncnergelic neutron
source employing the !Li(p,n);ISc reaction, was used to create
antl/or excite llir.se defects. Irradiations wore performed at
cilhor 10 and 77"K followed by linear rise annealing to room
temperature, nt rates ranging from 2 * 10"3 to 2 * lu" 2 K° per
second. A field of 1000 V/cm was applied lo the crystal just
before annealing. The current resolution of the electrometercrystal sytitem was ^3 * IO"15 A. Typical TSC peaks ranged
from about 10' to 10* times this amplitude for neutron or gamma
close of lhe order of 1013 neutrons or 1011 photons, respectively.
The prominent low-temperature TSC peak occurs at 31'K after
gamma irradiation at 10"K. This effect is characterized by an
activation energy of 0.093 ' 0.005 eV and is correlated with
optical absorption measurements at the H center. Two small
peaks on thr1 leading edge of lhe H center correlate with an optical absorption effect that has been attributed to interstitialvacancy recombination of anion defects. Since the II center peak
is not present after the 103K neutron exposure and the two small
peaks predominate, it is concluded that gamma rays at low temperatures predominately form the II center, and that low-temperature neutron exposure results In the Br" interstitial. The
amplitude of lhe lír" peaks are sensitive to the energy of the
bombarding neutrons. In contrast, the prominent TSC peak after
77"K gamma irradiation occurs from 110 lo 120'K, and Is characterized by an activation energy of 0.27 * 0.02 eV. This effect
correlates with annealing of the V, center. Although this peak is
prominent after ]0'K neutron exposure, it is not present after
the 10'K gamma irradiation. Hence, when the II center can be
formed, the V( TSC peak is not observed. The observed reaction
kinetics of the II and Br~ peaks can be explained by these assignments, and tho appearance of the V, peak is also consistent with
expectations based on these assignments. (Diss. Abstr. Int., B)
PASSAGE OF FAST ELECTRONS THROUGH THICK METAL LAYERS I.
D. Harder- Ph.D.Thesis,University of Wuarzburg,Germany,Jan.1965 . - A detailed theoretical and experimental study of the
problem,including discussion of the "charge deposition"method using a Faraday cage system. I t is
pointed out that due to forward-scattered secondaries
the absorption curves measured with the charge de position method and particle counting methods
giving only primaries do not fully coincide.
THERMOELECTRICITY IN IRRADIATED GLASS
P.CHaràtkOjArfionne National Lab.jArgonne,!!!
1962 Conference Radiation Effects on Glass,Rochester,KY
Summary Paper N.10
Measurements on °Co Satosiábc i r r a d i a t e d Calml^ g l a s s e s a r e
reported.The thermoelectric effect i s attributed to the
pBnetration of Corapton electrons from the Al jacket of the
cobalt source into the g l a s s . 1 M ^ l S Ç J í ô ^ S ^ l
effects.
*•
2$8
ELECTRICAL PROPERTIES I N IRRADIATED GLASS.
HorJlko, F.C.
Pupor given of Conference on Radiation Effects in Glcss. Rochester, N . Y .
Apr., 12-13, 1962.
THERMOELECTRICITY I N IRRADIATED GLASS.
Hardlko, F.C.
Phys. Rev. Letters, 9 , 339 (1962)
Measurements nre reported on the thermal charge release from gamma irradiated Cabaltype glass (calcium-alumino-boratcs). Doses up to several Mrad wore usod. The glass
svas hsaled in n temperature gradient (20-40°C/mm). Charges up to N T 8 cculomb/cm2
are observed. The discharge current is proportional to the temperature gradient and
shows several peaks which are attributed to release of electrons from traps of different
stability energies. Once carriers are released they can drift under the influence
of flie temperature gradient until retrapping or recombination occurs. The effect of
thickness and nature c-f shield interposed between the radiation source and the sample aro
investigated and found to be quite strong, shielding decreasing the charge displacement.
1
"
•
THERMOELECTRICITY IK IRRADIATED DIELECTRICS
P.C.lIardtke
Report|Argonne Ntl.Lab. 1963
2 61
\
•
F.C,U.ardtke,K.H.Ferguson,A.K.Gosh
THK FRACTURE BY ELECTRICAL DISCHARGE OF GAMMA IRRADIVíED
SHIELDING <
' VINDOW GLASS
?
4
,?
°
n / "i
Á
3
Report(Argonne H t l . L a h . ) ( l % 3 )
/
/
•
THERMOELECTRICITY IN IRRADIATED DIELECTRICS
F.Hardtke
_,
IEEE Summer General Meeting,Toronto 1963 paper #o3-1142
' THE FRACTUai-J BY ELECTRICAL DISCHARGE OF GAUlA-IHJttDJAT.:.!)
SHIELDS) VffiJDOV/ GLASS
F.C.Hyrdtke,K.R,Eerguson
11th Hot Lab.Proceedings, AHS,Nov.19^3,page 3&9
(Hew Youk,Nov.1^-21,1903) '
Measurementa on Éour-inch cube samples of comaercial sh3elfiin<
window glass. Glasses were discharged after exposure to 5~~
Z~t- HR 'by& n impact probe. Picture» of fractures and
ligth flashes are shown,light flashed oscilloscope traces
are given, and charge measurements aro reported ,the charge
being measured by a capacitor arrangement. Released charge
increased with exposure rate and decreased with exposure
temperature. It is found that a small dendritic fracture
once initiated will continue to goow vdth subsequent exposure.
26 S"
6f
7
I'll)W.OKLSCTZIICITY IK IRRADIATED
; Gfi'.'KUAL PKATOnEi:
F.C.Hardtke
. .1?,3000(1965)
DIELECTRICS.I«SOUS
Garrma-irradxatcd dielectric* are observed to produce
obo.rfíc release wb^Vi hetvUul in a tempovature gradient(5 to
40 0°/ imn i :raAi " I ' : ' lOn <3ose UP 'fco 1 0 **)* '•f'he released charge
(in one direction) was found to be proportional to the
temperatura gradient and to dose up to about 1 mega-H vfhen
saturation BB?,S.XÍ-ÍS .is observed» Discharge currents show
several peeks w.ci current roverbala are observed. Tho effect
of metal shields between rsdiation oourcc and sample and of
motal back pi a-tos were tiounâ to be surprisingly high. I t
io concluded that part of the effect ia due to the incoming
electron fluz,cí:ír,xt3Kt355;iiifíaaKÍ".isaieEa.v3E:jij.-±iuí»Ease and/; that
iSHxtncEWsss the difference^bistwecn the absorption coefficient
of the shielding ianterialxBiShe dielectric i s relevant.
Compton current theory i s used for a qualitative interpretation
of reoulto.
2*o
f
TijJSPJlOSLKCl'raCITY Hi IHliiluIATJi]) aibXECTHICS. I I .
HJSLATSD U'SUJJJIUS Mi D BPACfí CHAHOi. IJOWSL
P.C.Hardtke
In'^^ectretSjO^arco Storage and Transport in Dielectrics1
Coni".,Miami,October (5-13(15)72). The Electrochemical Soc.
2A1
'
Extendend
iVUi S&iJ ELECTiiO]! BKAI-J K-iüKüY DiTOSITlOlf PHOFILlià li3U:ü
sojju >uiDi.vno:; B^KÜITIVK r-k-.&rics
L.A.Uarrah
•
SC-}ti£-YO-427> Rep.Sandia ].aboratories,Albnauerque,
JToií i-exico, Juno 1S'7O
l
To bo published 'IEBE Trano.üucl.Sci. Dec.1070
1'iouauroà profiles indicate a pronounced range shprtcning
at charge flucncos greater than 0«5 nicrocoul/cr/. This
range shortening,due to charge trapping and field build-up,
reaches a constant value in the absence of apparent breakdown which is inuependent of charge fluenee at current
densities greater than 33 -a/cm for mean electron energies
oi" I.35 L;oV.lJoQO depth profiles at charge fluences in ej:ceos of 0 Ô Kiicrocoul/cn^ exhibit a lincarlj/ decreasing
back ed{;e which extrapola tos to to approximately 35>i o±' the
low fj.uenee range and a low intensity tail extending to
Greater than 'j5','-a of this range. A charge i'luenoo increases
the tail of the úoao profile acorecisco in rciatior. to the
forward portion. Kfi'ects arc. inter} roto.cl in len.i.o of a char.jc
depooition model including radiation-üinduced conductivity.
^,«
j/in-bi-;.^ in sc.we::
:;'.:J:.:-. K':..!ÍO.
:«:.K::/i?ic: r i..c:-:i:.:.-^
;.-..T:G
it 1)123 I V ^ i ^ u t i c i i u I ^ o i l . Ü c i . I^-IV , 27^(3. j.yc) lio C
U c o ^ i i . l c : i v r ó f í it on ifoi' -uil^od ;;icct.""c.: \>. • .:.::• in : ^ xiC
j.';'.i.i.li.t-.i.oi: ;.O'..;:i v.i vo pil;/_"l>ic.".j :• i: ..j. c i . b e ;i i :.'o;:o.u.<jt..•. :•..•_ "o
.•-Vvj.vi/'.iuJ.l;.1 j i n l;Lu i.l).;iii..cü oT ;.•._ j •.•.ru-^iri, b r . w i . v o ; ; : : : 1 ; . . : _„ ;. . c ; - , .
•to.iiii ; _; i'i:v,!iv.i'j;'. ;•. Í; « u v r c i r i ; (.•.oi.iji.ti'jy .^i-c:.t-^:;' t h t i n .'^ A / ' c : . /
f o r ;.(A-.II e ] >,o i r c i c:.'..::^ic^ o.i" J . J^;.iLO"' o V . ( ;;o.:c :;•,,, LI;
V'.voi'ilur:
. ' u v j.'.T'.t'-.'iiuc.i. c b o v o C ó l.J u r o u o v . i / c ; : . ^ ; . : i . l ' . : : L
.'.:':K;i..r!'.;. I.-.VCVLLÍ-ÍÜJ b^.ck e d ^ c ; cx..'i';.j;o.li..t.Ui^ t o ;.l>c '.I
'S/,'>
oi' t h e i o ' . ; j'.'.'.vii;iioc r;i:. L :t; uiiu
i',:iu ci lo'.i" i;:li.;:ci"t ( ': L;:'.i
c.:: t r L / . o l i i t i n j
t o ^ri,:.tc-:'.' t h i u i Cxi: ')y,. cu' I h i s ; j : ; i / . , ,
A c h ^ i ^ . C clc, Ot;i iiioil l;:oc:.ol i u d i u d i u j rt.dic.'bi we iud'/.t:-. d
o o i - . d u c t i v . i í ; i s v.rciiCiVicd
\
HMRAH, L., Stored charge effects on electron dose-depth profiles
in insulators, Appl. Phys. Letters JJ (1970) 421
270
If radiation-inducod oonduotivity is limiting the internal
field and assuming that this coad. and hence dose is uniform
over section of sample traversed by incident electrons,
trapped oh&rge density is
t
Q/A = £ kE = Jo (j-gE)dt where k =2.5 is diel.const., B
el.fiela,J botiin cui'rent density, g rad.induced' conductivity.
Differentiating and equating to 0 to find limiting field one
has B = j/g and B *> l ^ K / ^ g ^ »where B, nean is effective
mean energy of electrons, R their range» K ratio of prompt
conductivity to dose rate. Using the observed limiting
field of 2.85x10^ V/cni one gets K^LôzlO" 2 ^ /(ohm cia)(rad/sec)
Injection charges of 1 nicro-C/cm^ an& above produced
"saturation",i.e. no further range decrease(beyond about
1/3 of initial range,0.28 against max.O.78 g/cm with 1.5
I-GY electrons. The secondfc.follo'.rsfron the e::pre£L:âon for
doat rate
y, in !IcY.
:
HA3JIATI01T VilirooVJ GLASS
H.V.HarrinetoJi
U.S.Patent 3 356 579 ,Jan.25(1964)
Describes a class resistant tg dielectric broakdem
from canina rtidiation up to 10u IÍ, consietinj essentially
of up to 47• 2;i vt.SiO2*,33^ irt.FbO,17^ vrt. KoO,2.8;ó -.rt.
Glass is characteriaeci of being substantially free of
haloeens, soda,and lithia, havinc an initial luminous
transmittance for a one inch thickness of greater than
90^ at vravolensth of 55OOA°,and having an electric
resistance in terns of the logarithm of resistivity
of less than 16.5 at 50°C.
27/
7/
• GAMMA-RAY PHOTOCONDUCTIVITY I N POLYETHYLENE, POLYSTYRENE AND
; IPOXY FORMATION.
Hgrtison, S.E., Snydor, W . A .
In Conference on Eleclrical Insulalion, 1961. Washington, NAS-NRC, 1962. p. 25.
ífyblicolion no. 973)
•
0 yq
* 'L
Pliotoconductivities have been measured in the range 1 rad/min to 3.10^ rod/min.
Source of yaiwna radiation has bson (he fission product inventory of reactor fuel elements.
A STUDY OF GAULiA RAY PHOTOCONDUCTIVITY IN ORGANIC DIELECTRIC
S.E.lí"rriBOn
Ph.D.ThesiBjUniversdty of Hew Koxdc-> 1°62 AEC TID-15482
'
Detailed investigation.Sadiation source used are spent fuel
elements, the arrenseiüent being symmetrical so that Compton
current is eliminated. Influence of dose, dose/ rate, time,
, and volt«so have Vfien studied,
5
111
MEASUíttíD BSHAVI0R OF GAMKA-HAY PHOTOCONDUCTIVITY IN
ORGANIC DIELECTRICS
S.B.Harrison
n~..
Paper CP-62-1251,IEEE Bummer General Keeting,Denver,^une 1962 11{f
It has boen found that decay can be represented by sum of
exponential a.
- I
GAMMA RAY AND NEUTRON-INDUCED CONDUCTIVITY IN INSULATING
MATERIALS
S. E.Harrison, P. N.Coppage, A. W.Snyder
_..
IEEE Paper CPA 63-5156 (issued by Sandia Corporation,Albuquerque, New Mexico,USA) , >
' (SlectroiJiicl-ear Conf.5Eichlanâ,feü:iinç;ton,i-.ay 1 (lybj,)
lieasurements by steady state and pulsed sources ase reported fo:
polythene,polyethylene^rajflar,teflon etc.). Steady state
gamma dose rates were 1 x 10~3 to 1 x 104 r/s, combined
pulsed neutron-gamma dose rates were.up to 2 x 10" r/s.
Sautes On inset of radiation, conductivity increases
and reaches an equlibrium state according to an exponential
lav/ with a single time constant. Conductivity decay after
radiation has ceased is reprsented by a series of exponentials.
The qquilibriuJW conductance contains a component arisins from
direct excitation of carriers toy to the conduction band by
irradiation and another component arrising from thermal excitation of txs^sáxB&vxí carriers trapped in non-conductive states to conducting states.aEkzxx The influence of the release
of trapped carriers is responsible for the the induced conductivity response and and it3 decay. This influence is,
hov/ever, notable only in the steady state measurements^
Gemma Ray PHOTOCONDUCTIVITY DECAY III ORGANIC D I I X S C T J U C
kATKlIALS
S.l^Harrison
AVüB Conforonoo Paper CP 63-1143
Sandia Corporation Reprint SCR-671 (Sandia Corporation,
Rsarx Albuquerque,New Mexico)
Conductivity decay can bo represented by a sum of exponentials.
Amplitudes and time constants ef for this representation wore
measured for teflon,polyethylene,polyvinylchloride,po]ystyrene,
Kel-F, and nylon, for temperatures between 29°C and 80°C
and doses between 3.3 and 6.7 r/s. Results ssurixinter preted in terms of a trap-controlled process. Curriers are
of on3y one typo and the rate at which they enter the traps
is during the decay assumed to be small compared to that at
which they leave the^( trapo,
PCLAPJ.ÍSAT10U EFFECTS Hi IRRADIATED SIDGLM-CHi'STAL
J.W.Karrity,U.K.Leadon
In:lS68 Ami.Kop.Conf.lil.Ins. ILiS-lOÍC Publ. 1705,
Washington HC 1969,P.18O
Irradiation effects by 30-MeV electrons,samples mounted
in a, vacuum chamber. Effects arc bolieved to be due to
space charge caused by nigration in the field of tlio
low oner©" electrona (a few 100 eV) produced alone the
tracks of the hi^h enerjjj' electrons. Conductivity of
various materials(Dapphire,quarta,Pj'rex etc) were
also investigated. - SutcessiVe/r'puÍaèsonon a sample
with, a constiint voltage bias resulted in increasig&ly
lower current pulses.On removal of bias,subsequeit pulses
gave a current flow opposite to the previous one.This
polarization effect is believed to fee caused by the
space charge x - production.The effect was observed in all
samples, but was small except in sapphire, which also
exhibits an induced conductivity 2 orders of aagn^itude
greater than in other dielectrics.Samples wore 20 mills
^thick .Up to 10' rad vrere applied.-SIliGLB-crystal samphires
exhibit an induced conductiviiy30 to 50 times greater than
of other materials tested.
,
]
ft'i(-/3íT CF SKCOrtWLfcY ílhcnQtí£
,7 .V. Ha w i l y
Vu;U.i- j i»r;*.í.lu.tion vi. 11
; , 'L'J.*i'/'' '• -1. ; V
'I ..'..' i 1 0 J . ' C'iit'.l l i
//.! i'APPH/.Raf
i. 3C J.OV o l c c t ^ o - : "rj;j;.n i'rc;.. ;-, 1,11 .'AC
'..\ •"' O i ' ••' •• .'\'\J\X.
í',11 i *j •_) è 1 . l l 0 1 : lí
; . 0 VIJ. -L11C1. t' i-'-'J.-1 i- **'*' '*>» LC' '.! O.-
COílO.UOUj-V.l 'u(l.
'.'.I Vil
' ü i i . . u '.':l t ..L.*i-'-lL
.'. '.:'»...
\-0
J-'í-. • ..' t . L..1. C ;1—11 ULwlO ..(l
L:Í, íibout IODO" A ° .
278
J.'Í.Ü uiici\-;y values í'or i'ov. ic.tior. oi' ipn _-:.ir i~ t..!:cüi 3 'ti;..cn
ti.o ioni^;:'uio;i rotoiitiíi.! ('.J.V cA^13 JL.Í";•_;:.:•;.;."tioii I'l-.xc i n
1-rlO-'-^ c-ion p u i r o por c:::.-^ r.riú r..:L>.'oí oloci DJ/OÍ.IO ,:itJi norc
;.i:.i c!.:^'. -'iras :lo:ü ;jt,tio:i i.'ute 2.5"•:.'• 0-^ j :.iri; ;.cr o...
.'oii.Vot^l no.oi' ;.:^co!!v:.ri:;r.' p e r ip.jidont r;ri:. •.:_•;•
".'^--íl.jxlCO d j •..'-•-cru d iij thiíjl.iiO^;:: oi' i;:.: tj lo.Soor.' ,.i-i;.::.
"r. •.'i/C voiní.r.' zii^v.~i>-'lzú.Q~^° ci.Vi^.p c.c^^it;/ i n os;t:'.: .-..tea
to to c . V
* / *
t/ii
n ia c a r r i e r cicnait.y, ;j ^oiiüratiou rato of c:!.ri'icrs,-i;;io"ot.'ior
cor.ütantc 'ocânf; rospootivaly rcjco:..'binatio"!) ti;..o const. -tra/Aiiy
tiü.c const., r.nil u.^. density of tr^i^jed c a r r i e r s , u iii;itr;'.;.pin:;
t:i::o coiictr.nt.
_
_
.
.
í
THE COAXIAL OOMPTON DIOPF.
D.W.Hart
Preprint,/.p^.ied Phy3.I5iviyioji,/.V/KE(1965)
j
Refera to Conpton dielectric detectors..Tt ie BUg-gcáted that
account must be trken of the volv-jue ih&ríja distributioíi
ia a dielectric Compton detecuor.lt is also eho\7n that the
tíielee-trio constant ahcald \>v. independent of frequency
over the envisaged range of operational frequency and th.it,
for convenience of calibration, the resistivity should be
high. A general theory of the detectei- is giren.
TRANSIENT SPACS-CHARGB PERTURBED CURRB2ÍTS FOLLOÍÍIHG TIMS- *
DEPE1IDEIÍT IUJECTIOH
G. C. liar tmann, IT. 0. Lipari
J.Appl.Phys.
(
The problem of space-charge perturbed currents in dielectric
media is studied for the case whore the charge injection
at one electrode is tin:? dependent.Sinee the analytical
approach, is very difficult,eq.s.governing charge carrier
dynamics have been solved numerically.The special case is
considered where injection has an exponential time dependence.
A constant voltage boundary is asoumed. Results are given
for configurations consisting of one and two dielectrio
layers.
770
'1
z
Y.-WJJ PJiOTOCirnUJTlCtf, 117 r^OTCCOlIuTTOTICM r.V.Ti I-'UTO-t/ISei^UU
a. H s 727(1962)
The l'O-:''.vj nv imclcr Z-vadAvtion nrid XT! i^üdiatioü i s
Vaite cliff w e n t / .vit.h rt'£;vr-d Io clnj^ndcmce on voltU£O,
ten!p:3rii.t.ur-e,aot.5_VLtJon o/T-n-^y, «íose -.-P-d dose r a t e . Previous
fe i r r a d i a t i o n by X-rays rtiouciys th/.- current conduction ur.dftr
•volti^'--- -this i s explained by the proãuot5on of rpcoiubiiiation
conter»»
|
.
I
j
1
j
.
I
'
32620
CARIIIKR GUNHRATION IN OnTHORHOMBIC SULFUR CRYSTALS BY I'ULSED X-RAYS. Hoyashl, Kotaku (Osaka
Univ.)i VVntanabo, Ynsutal.ni Inuiohi, Yoshlo. Teolmol, ROD.
Osaka Univ.) 21: 5ai-'i(Oot 1971).
The mobility and carrier number In ortborhoinblc sulfur crystals
bombarded with pulsed x rays at 100 kV were measured as a functlon of the apiilied eleclrle field or x-ray intensity at room temperature. Results show that lhe hole mobility Is 0.26 cmVv sec
in fields from 20 to 56 kv/cm and the produced carrier number
Is approximately proportional to the square of the Intensity, (auth)
PHOTOCONDUCTIVITY ASSOCIATED WITH TRAPPING
Ztf'
I
OQO
* " ~
'
J.R.Haynes,J,A.Horribeck
Phys.Rov. 20,152(1953)
Discusses effects of two sets of traps, a shallovr trap vath
life time of LG~ 2 seo and a deep trap with lifetime
(time electron spends in trap) of 260 sec, while lifetime
of electron in conduction band is 2S microseo. Wien light
switched off, conduction band empties before electrons are
released from traps whoch occurs in two stages.
RADIAT101I * INDUCED ELECTRICAL CONDUCTIVITY Hi POLY AMIDE /
COPOLBiEfíS
.
P.Hedvig
'
'
1
J.Polymer Sci.A>g2,4O97(l9f>4)
\
Radiation-induced conductivities up to 1O~ /ohm cm
were measured in polyamide copolymers zííxax X-ray or gamma
ray assagBs dose rates "between 0.1 and 20 R/sec.Ho temperature effect was noted between 1O°C and 60°C.Por dark
conductivities an exponential rule with H S activation
energies between 1 and 2 eV was found.
I
SPACE-CHARGE-LIHITBD CURRE1ITS JXS HI A1TTHRACENE AMD
THE DKDBRI.1IMTI0H OF ELECTRON MOBILITY
W.Helfrich,P.Mark
Zs.f.Physik 160,370(1962)
The paper discusses the movement of electrons injected
through a non-blocking (ohmic) contact. The steady state
current and the transient current ere calculated. Eqs.
for the transient current are rigorously solved for
ika times smaller than the transient time. Vlhen the
first electrons reach the counter-electrode, a current
maximum (cusp) is reached whose position determines
therefore the transit time.The mobility follows.
2/jà.
~
q
•••i'1!'jv VO l);:T'';'r;iT.MK TiVA Y'TiXimvS,
01;' VOLTAGE B l t í À K ;
i)O .;;:':bi]:i vo'PKOYÜÍ? ÍIÍRADIATION IN POLYJWRIC
\
II.]).lIcndricT:B,••;•.]•:.Miller, .
lfov.1968
].T/l<3,'...Ti-.-X-l6n8. (Natl./.oronautn.cs-i and Space
Adni'n •*' f < t r at ion, Lanp-1 e 7 S t a t i on , Va. henrrl ey Roa. C enter)
m a t e r i a i s v/as investigated.Kapto:
j t o a f ; or jnd-uc^a voltap;c breakdown wan o"bqervcrí vbis Í'H in contract to the numerous observation
nf bro'^-dovmri observed for electron i r r a d i a t i o n of
Biioiipr'Uf'flnm:i.en.A theory by Nichols ond von Lint
r,r';ri-ifts t h a t a behavior of t h i s tüpe should be lesn
ent bccii>f;e of x>ro+r;, r a t h e r than e l e c t r o n jdmc
iriYicM.nt.ion.
421G2
(NYO-3-109-10) ROLE OF TRAPPING PROCESSES
IN SOLID STATIC HADIATION IX3SIMKTRY. Final Report. Henisch, II. K. (Pennsylrunin Slate Univ., University Park. Materials
Research I-nb.). May 1971, Contract AT(30-l)-3409. 40p. Dep.
NT IS.
Itcseaich progress on new ideas In solid stole dosimetry including field enhancement of thürinolumincsccnce, photo-stimulated
radiation doslmctry, current glow methods, pyroelcctrle method,
and dosimetry by electric depolarization is reported. Polymer
eleclset doslmetry atid a teeluiique for the measurement of pyroclcctrie coefficients arc discussed in detail. (W.ÍI.K.)
)
1Ú
t~q
IDaáüI&TIOW DAMAGE TO GLASS
Í
J.R.Ilensler,N.J.Kriedl,li. L en,J.L.Rood
Bausoh and Lomt Inc.,Rochester,NY. TII)-14482,Kov.3?6l
Discharge eKperiinents en electron-and gairnna irradiated
lead s i l i c a t e glasses are reported. Gamma radiation induced
discharges occur only when the gamma beam strikes the sample
from one direction;discharges were never observed for i s o tropic irradiation.
:
"
:
-
-
-
-
-
-
•
•
-
\
•
33ull.Ujner.Phys.Soo. l8,ifo.4,5 54(1973)
A M 3 Contact-less, Local Free Carrier Property Determln
atlon in Semiconductors. J.C. Herper, I. Palocz, Neu York
Univ., R.A. Stern, Bell Laboratories, and N.H. Axelrod,
Norman N. Axalrod Associates. N.Y.,N.Y. — A nevi diagnostic
technique simultaneously measures the free carrier lifetime ( T ) and diffusion coefficient (D) with spatial resolution in localised regions within a semiconductor. The
technique usou pulses of above band-edge light incident
on the surface of a semiconductor to inject bursts of excess carriers near the surface. These carriers diffuse
into the bulk and decay (e.g., by recombination). A narrow probing beam of below band-edge light traverses the
semiconductor sample parallel to the illuminated surface.
The changing excess carrier dennlty along the beam path
causes a corresponding absorption in the probing beam intensity, and is monitored os the beam emerges from the
sample. D and T are obtained by computer fitting the absorption curves to an equation for carrier transport for
different beam scan positions normal to the illuminated
surface. Experiments with a 100 watt xenon arc lamp, a
3.39llm HeNe laser beam and a 1500 ohm-cm silicon sample
yielded values of D~20cm2/sec and T~0.6msec, in good agreement with independent measurements and calculations.
p. rs*
'
- -«
2o~f
34893
POCKET D0S1MKTK1Í. llorzog;, Heinz (to Tolefmikon PiitentverwcrhinRPgcscliychiirt inbll). German Patent
1,514,804* 23 Oft 3DG9. Filed 30 Mar I9G5. (In Carman).
A jiockct dosimeter for the measurement of x, gnnimn, and
neutron radiation made up of two cylindrical conductors under
vacuum arranged coiii-ontrically and of different sensitivities to
tlie electron energy is described. The exterior cylinder forms
one part of a wall eniilosLng the vacuum. There is also an electrometer indicating tbo difference in potential between the two
cylinders. A switching foil is nrnmgcd in the vacuum enclosure
but maneuver able from outside the enclosure, serving to discharge the electrometer, U.K.P.)
*JQ *\
*~ / I'
1
All X-ÍÍA1 PJ.'OJ'OCELL
B.'Kor.a
20/
Dorscribes a vacuum Cowpton doseineter .
!
•
'
J
US'J OF F?,RBOELKC?HICS FOR fiAi.jJA KAY DOSILiKTOY
T). 1;. Jie B t e r , 1). D. 03 o wer, L, J . Over ton
Special Technical Conference on Nucloar Rr. ô i a +,3 on E f f e c t s ,
S e a t t l e , J u l y 1961
IÜK3 Transactions Huol.Sci. irS-ll,):o.6(Kov. )>145(l964 )•••-—.
29 Z
Irradiation of a poled ferrouleetrio causes a release of charge
v/hich was found to vary linearly with close. Sensitivity was
—12
2
10
coulomb per rad and cm of «lootrodecl surface area ,for
polycrystalline PB(Zr_ ^ r f fi rt , r ) 0 ,, , . A , , _ .
,. A ,
+1
O.05 0.35'' 3 wt?"""g0^,irradiated
in Sandia pulsed reactor, A similar charge relcaBe v/as observed
in poled barium titan&to .
(Bull. Amf$3o'c. Ser. 2, 33, 1968, 560)
\
1 AE18. Application of Self-Powered Gamma Detectors In
/ Monitoring the Intensity and Position oi Bremsstrahlung
/ Beams, J. \V. HEWITT (introduced by K. G. McNeill), University of Toronto.— A self-powered detector consists
basically of 2 electrodes of selected materials separated
by a dielectric. When the detector is irradiated, a net electrical current flows between the electrodes. No bias voltage
Is applied. Such detectors have been devised previously for
thermal neutron flux measurement1 and for monitoring intense gamma fields in reactors and irradiation facilities.*
The sensitivity of these devices is relatively low (~ 10~"
A/R-h" 1 ). Therefore, to take advantage of the small size
and Inherent stability of such detectors in experiments using a low duty-cycle pulsed bremsstrahlung beam, it has
been necessary to amplify the detector signals on a pulsed
basis. The details of construction of the detectors and a
description of the associated instrumentation which processes the detector pulses to indicate directly both the
Intensity and its time Integral will be given. To demonstrate
inc usefulness of the system, the measured beam profile for
30-MeV bremsstrahlung produced in a thin target by 10nsec Llnac pulses will be presented and compared with the
profile of the same beam measured using nhotonuclear reactions.
• .
• j . W. Htlborn, Nucleonics 22. 69 (1961).
• a . B. Shields, CRNL (private communication).
v .
S .
HEWITT
2 S
3
T
!
/
v-;.y>?••.•;.•••; •.•••rr;T-y;a 0 7 J . '•'..::w rvr-í:.',v;>.;..vi/:.:o
-
-
•
rv/0. -..'.• :.^i.;:ví -..rü-lo tf0**» 3790-972)
l ' : : á v . ' : ' : v o ; i l G , • ..•..• .C;.c:; . 7 : - ^ : . . .
:'!:;•
o.1.'
;...-••
-
s
1
•'•••-'• : 1 ' "
. : . ; • : ! ; 3. •.•.c.-''.'-'---1'.o:-.':.1
L e r : . Í . . ' :•.•:•.].;' ..:..;^
•,<r. : . ••\i.\-i
''•-..
'
;
:;
f o r
;
A; •?l.Ch-s.i.}
:..',;;<:•- - ' i - v o t i ; - . ; .
:;
\::oi'i'i'jt
; : : - r : ; : • : . : ' : • -Í- •* :;.'. : : O Í . -
v
r :.•"•:''. v
'"..•;•
1.: ••
o
••'-'•
' t i ' l ; . '• 5 '• •!••'
u::r1 o :
"f.-iàttcr-"
. . L'.ou
••.•:': "i:-i.":i i t .
ô o I:.-o'LOT
:-tr:lp.. ;•:-.•;" "•.!. :v ; ^u; rr:•:.-:. l-f-t'.K-o:! !! ;:
f-/".w:.••••' ..''0
i'-oi-ovito J.'.'•?. ,C:vt .Car.?.'
h;.r;
!.- Í :
IKC r^.
c .'
of
"lhe
;'o'. .\t: c r . a*>c.
r.-: j
.ontoO
:
iijl^"-::*;.
i " c : . j y ' : ! o : . l>o..'<v.•.•"•:-. :• i . i ^ - i i ^ o t o
;v• :?o~
Í 1 "'"' i'"'•..'.''''I.:i •.''.:• ."'. t- •' ' . t o v . ' . ':'::. •..•i.T.^o
o:" o n i ; p v l v--'i-ti-.jc
i u l : : . ; ; "!; •..: ' ' • : : ' . . . • : 0:1 o n í.'.r, v ^ r í ' c . ü a r - ^ o i r . t L.'}.<>::^ t h e
cli i.'.-r. ••••.•.•." . i v :<•'"' :. i w n h i : . ; o " . " • . . s d i . l i c . i o a r c r i : . - t o
. h e r . 1 ?,!': ' oV (?'.!.•• v'...-;•••;.; i">;.';:.i'.L •..-.•it:: 10 ri: :v.l..c-~ Vr- ;-..r -.'ji'lj
/
/
a 0.375" tliiok no-tal t a r g e t . A magnet f i o l d of )dlo1
GC'.UB:.; nac;iiituc.e iras used to deflect electrons out o£
tho riáei:i«stra3ilunc "beam. Pulso r e p e t i t i o n r a t s 17ns
CO HB, each pulBü containins 10^ oloctrona. Pu lac chr-po
\ras ro-ifj-tercd v;ith a 512 cliatinel atv-.lyacr. íhe sj ctsui
can locate the coutx'oid of tho beam irith an accurncy
of hotter thcin 0.5 nun fvhn over a disijlacenent ran;;e of
at leftot 3 cm.
'CHANGS OP ELECTRICAL POLARIZATION OF HIGH POLYMERS UiiDES THE'
IIJl-'LULNCE OF IONIZIKG HADIAT1 OH.I.Transitory CHANGES.
L.Heyne,0«Hauser
Kolloid-Z.u.Z.Polymers ^0^,39(1965)
onf
*/-
lleaaureraonts of induced conductivity and of depolcrization
current were made for various polymers • Transient
effects can be represented by Schweidler's lav/. Those
dielectrics v/hmcb v/ithout irradiation abov/ed the lowestconductivity, showed w±±x under irradiation the highest
conductivity values.
CHANGS OP ELECTRICAL POLARIZATION OP HIGH POLYÜÍESS UNDER
THE IUP'LUiMCE OP IONIZING RADIATION - I I . P e r m a n e n t Changes
L.Heync,0.Hauser
•
1
Kolloid-Zeitschrift und Zeitschrift fJoly/nere 206,20(1905)
A strong permanent increase of Epxis 10
and more rsmsJaas
• ,. *./
Á
of the paraelectric susceptibility remains after high
irradiation doses. It Í3 attributed to stable changes of
molecular structure.
r
'/*
'DIB USJi OP 'JIIKRl^iLLY STIIOJLArED IOtfIC CUiiRKJITS WITH A
HYPERBOLIC HEATING RATE TO MSASUHK «ODIUM LOTION Hi IfFSPUTTBliiiD SiO ? Films
Appl.Phys.LetT;. 22^,267(1973)
•P.W.Hickmott
f
Analysis follows Ilaering anaa&ams for thermally stimulated
conductivity curves in photoconductors.Assumes single trapping
level, n. concentration of trapped charge, n of mobile chargo,
f i r s t oror k i n e t i c s . Gives
dn-t/dt = - ntox/}(-E/kT) +n o (Ut-nt)sv$dn c /dt=-diit/dt-nc/r
J=<trF =ev/d j cr= nç<l/M , where E trap depth, lit t o t a l trap number
v velocity of mobile charge,s cross section for retrapping,
lifetime of c a r r i e r s freed from t r a p s . Integration carried
out for for re trapping neglected, dn c /dt
/ / /
(hyperbolic heating r a t e ) .
SELP-POIVERED NEUTRON DETECTORS FOR REACTOR PLUX M0NIT02IH0
J.V/.Hilborn
I
Kuoleonics Vol.22,No.2, page 69(1964)
Describes detectors made of coaxial cables in which the
electron emitter is a conducting'or semiconducting material
that spontaneously emits enorgetifi electrons under neutron
irradiation, the insulator a solid dielectric, and the
oollector a conducting material that produces few electrons
in a neutron flux eo compared with the emitter» A system
for compensation of the Compton current is described.
Measurements made in reactor cores are described.
'
\
j
I
j
POOLE-FREIIKEL CONDUCTION III AMORPHOUS SOLIDS
R.U.H111
Phil.Hag. 23,59(1971)
•i'he theory of the ioniaation of local isasibs defects by an
applied field is investigated. The Poole-Frenl:el effect ic
eho-sm to be a limiting case of a more general analysis covering
the experimentally available field of electrical stress and
temperature. At low teuperature, conduction is due to tunnel—
lins ECZ±XK£ emission out of the defects into the quasi-conduction band of host material. At high temperature thermal
enission becomes predominant. In between a therr.ial-field
emission procesajziusE^ansLsxfSJíãrrmrnriçni. has been identified.
Poole's law occurs when the density of ionized defects is
sufficiently great to give overlap of coulonbic potentials
Bourrounding the defects, and Poole-Prenkel effect occurs
when the centers are non-interacting.
2/J7
ELE0TR1C CüBREXT DUE TO GAMMA-RAY IRRADIATION
Jap.J.Appl.Phys. £,305(1966)
A theory of the current is developed supposed to "be valid
up to 50 KeV» Multiple scattered quanta jwaàtfa: are neglected.It is also assumed that pair production does not re
suit in any measurable current.
I
HIGH DOSE DETECTOR FOR GAMMA-AND X-RADIATIOK USIGG
C0L1PT01Í SCATTERED ELECTRON
l
E.Hiraoka
Jap.J.Appl.Phys. £,299(1966)
a Conpton Dosemot«r identical to that of
;.:(jasnre:!iou1;s two reported for 6oCo gam in a radiation
1'j I.loV lijmio radiation. Sensitivity "v/BS^of the
order of ?,5 x 10-14
'
A / cn ,2 p G r R / m j n #
A SILiPLE ALBIIOLAR MOJJííL i-'OU TEE ELECTRO1T-33OLIB.'UÜJ;-:Í;Í;I'CClãXüCTlVlTY I I I AlúOIUJHOUü AKSKIíIO TRISULüTiJiS
J.líirsch
J.Chera.Solids 22,1385(1966)
202
Cii1.' co"Ti.'?V'.';rr'iC-r i ; r
i
;
J
2
1
,
(
)
KffÔcts :.uo to p-Lil!.:o'.L ' •ci./burd.v.on-i 1:; fully i-.cnitr^ti ::j
ilocti-or.o arc ir.vcfjtijated.Kir.o-iicr. cbo; c.i i;. tho'Sr;. .;-t"
co:.";poti3r:t of ÍT.CIUCGÜ cu.rrent are i.i'ci.oi.'.in;'.'.;^!; f i r n t oí.orjthoco
of
the "lo:i1j--livo.:L"cv.Trio:at ÜÍ/COIÍCÍ o -dor.
lícüv.ítfi con:'"ir:ii the- :ir:ter]rotation of the decs.;' "iii.:o
of the lo:^;--livoà cui-r^nt ac a Mi.iolcs..lv.z •x.-ocy.^iiu.iizv.
lifotiii'.e.A KÍ!;:V.1Q i::o(3.ol for radiation iu.'-iw;JL oo:-/iuctj.'jr.
in j.^1; r.eru/or-oed on topolo^ioal ccisidoraticno } i s
dovcj.cycà.Lov:^; lived current i c a c ^ a c i i t e i iritli ir.tcrr:oleci-.lui- Ji^ps.Vtile the effective n o b i l i t y of the
lo:io~livcá co:.'.::cHQnt(uc deduced in l}i:i idrJicd —cliain
pol;:";ers i s controlled b;. the i'.itsnr.oleculcr ivjnp picca"bilit;/,that i n pel; oth'.lcne ia cul3oect to v.n addition-.1
limitation,viz.etron^ Isarsüaii localization
of c a r r i e r s
it: the U to rid o of the noli.cu.lco.
1
THE EBSPOFSE MBASUHEMEHT OP LASL DIAGNOSTIC DETECTOR
L.P.Hocker
EGG 1183-2238, S-49O-R (l97o)
305
BBEKSSTHAiJLUlfG SHIELDING PROM ELECTRON TKAPPIHG III
DIEL'ECTIilCS
D.L.IIollio
Huclear Technology 00,325(1971)
A study is mad© of utilizing electron trapping in dielectrics
as a means of reducing bremsstrahlung in spacecraft at synchronous altitudes.Traps retain electrodes, and large internal
fields are induced in the dielectric.Electrons penetrating the
material can lose most of thoir kinetic energy to the field
with a corresponding docreaso in bremsBtrahluns loss.This acts
to reduce Bremsstrahlung and lowers the average radiation energy of that which is produced,thus increasing absorption probability in the \;all.Breakdown phenomena cause shielding
effects to be cyclic.A thin dielectric layer on the external
surface of a ppaoecraft should provide an effective,light,and
inexpensive shield against bremsstrahlung iiithout interfering
with any of the systems functions.Electron-trap shielding is
applicable BXESjcwherever a dielectric-charge layer is allowed
to accumulate.
J
RAMATION EFFECTS ON COAXIAL CABLES AND INSULATION «AN
ANNOTATED BIBLIOGRAPHY
W.L.IIollistor
Lockhead Missiles and Space Company.Sunnyvale,California,
Special Bibliography SB-62-12 (1962) AD 278 674
Refers to the effects of mixed reactor radiation on transients
and damage effects in both ooaxial cables and electric imsulation materials.
1
1
['
I
479
(N-70-31746) LITERATURE SEARCH AND RADIATION STUDY ON ELECTRONIC PARTS. Final Report. Home,
W, E. (Boeing Co., Seattle, Wash. Aerospace Group). May
1970. Contracts NAS7-100; JPL-952565. 258p. (NASA-CR110496; D-2-126203-3). NTIS.
For Jet Propulsion Lab., Pasadena, Calif.
A survey has been made of radiation effects literature pertinent to effects of low-level steady-state neutron, gamma, and
proton environments on electronic components. A bibliography
of over 300 references was compiled. The data were scanned
and an analysis made of the radiation effects state-of-the-art
for electronic components on a deep space mission that might
be exposed to planetary radiation belts and to on-board radioisotope thermoelectric generator environments. Emphasis was
placed on permanent parameter degradation, temporary parameter drifts, parameter degradation factors, hardening techniques,
and screening techniques, (auth) (STAR)
•
;
SELF-POWERED DOSIMETER FOR OÁLHiA MD X-ItADIATIOH
R. Ho somann, P . H. V/arrikhoff
Kuoleonios 22,Wo.3,51(1964)
I
'
I
\ RADIATION DET32CTOR WH03E OUTPUT I S INDEPENDENT OF TH3TEHBRGY DISTRIBUTION OF INCIDENT RADIATION
R.Hosemann,
H.Warrikhoff
'
A—<íe-t-fee-t-er—e-l&o-t-reá-e—strtte-t-urc—composed o-fMrwo—tyi3E5
il^Qtro_de_s._at...lea_Si.
- -• •
^j>f_layers each made of a material and having a'thicknes
-l-aye-r^-- -oombiite—
. _ J L J . c h 8 X g e . carrl&rsb^4;wfe&n-th
e l e c t r o d e s to be independent of the energy d i s t r i b u t i o n
3 0g
j
/
|
A HEW ])IRECT-REA1>X1ÍG
REQUEST MAINTENANCE
PERSONAL DOSEMETláR VÍHICH DOES HOT
/
R.Hosemann, J.Haace
Acta Modiotecnica -4,42(1970)
*~
57776
NKUTUON DOSlMETftY WITH RADIATION KLE- "
MENTS. HOSCIIIHIUI, R.i Hoase, J.j Junker, D.; Melde, IJ.
I'ritz-Haber lmlitut, Berlin), pp 373-bO of Advances in Physical
and Diologiei.l Kadiatioii Detectors. Vienna; International Atomic
Energy Agency (1971;
From Symposium on new developments in physical anil biological
radiation duloeliirsij Vienna, Austria (23 Nov 1970). Sec STI/I'UB2C9j CONF-701112.
'J'he radiation dement Is a vacuum cell with two special electrodes that arc chained when Irradiated. The resulting potential
difference la measured with a quart/-fibre electrometer, lodlatlon elements are self-powered, mc.i3urc radiation dosed índependent of do.r;e rate and have a practically unlimited storage lime
due to their extremely Kood Insulation, lladialion elemcnls become
charged If the electrodes emit different numbers of electrons. This
is aeiiiovcd fur X-rays and y-rays by using electrodes made of
materials of different atomic numbers. Slow neutrons are captured
in an electrode madu of silver or rho-.üum by a (n,y) process producing short-lived /--active isotopes. Kor fast neutrons a moderator must bn used. Fortunately the human body ha» the optimum
dimensions required for this purpose. Dosimeters with radiation
elements therefore cannot measure free air doses of neutrons, but
careful Investigations have proved thai they are reliable indicators
for neutron fields that are of Interest in accident dosimelry. Dosimeters with silver electrodes of 0.9 cm o.d. yield a sensitivity of
about 3.5 V/rnd to thermal neutrons and 0.5 V/rad to eplüiermal
neutrons, which correspond to full-scale readings of about :*0 rad
and 200 rad, respectively. Dosimeters with the same sensitivity to
thermal and cpithermal neutrons and y-rays have full-scale readings of S00 rad. Uoses between about 50 and SOO rad, which r e quire Immediate medical attention, can be read off directly,
whereas the less dangerous doses, between 5 and r>0 rad, arc stored
PHYSICAL kEASURJiiE.í'i'S OIT A 2 l-ieV X-RAY OElffiRATOR
J,C.Hovartli,J.L.Jones,H.Miller
j
!
I
I
„
Q It)
3
/i
Brit.J.Radiol. 24,665(1951)
Reports polarity effect in ionization chamber
measurements .
PHOTC2T Cl'COSS SECTIONS, AT^íErUAVIC?
ETERGY AUSGia'TIo:;" COH^ICIKM'S PÜCií 1 0 keV 'TO 1 0 0 GoV
J.II.Hubboll
]rsi{Dd-irBs 29 ( 1 9 6 9 )
( R e p . i l a t . S + a n d . lief . D a t a S e r . , I T a t . H u r . S t a n d . , U S A )
ELECTRON BEAM DETECTION OY CHARGE STORAGE IN
MOS CAPACITORS
E.E.Huber, M.S. Cohen, D.O. Smith
Appl.Phys.Letters 15,147(1970)
MIT,Lincoln Lab..Lexington MA/2173
a,o
JfC>
40Í73
PROTON HOMI3AUDMHMT INDUCED CONDUCTIVITY IN ANTIirtACENH SINGLE CRYSTALS. Huber, W.;
Scharmann, A. (Univ., Giessen, Ger.). Z. Phys.; 236: 383402(1970). (In German).
Transient currents in anthracene crystals were measured under
bombardment by pulses of 700-keV protons, Electron— hole pairs
are generated by an intrinsic process, tho yield varying linearly
with tho intensity of the bombarding beam. The average energy for
pair production is found to be 10* eV. The temperature dependence
of the carrier yield can be characterized by an activation energy of
0,07 oV. The results are discussed with regard lo different models
of tlio generation process. Drift mobilities of 0.40 c m W see for
electrons and 0.88 cm'/V sec for holes me determined in good
agreement with other authors. A reduction of tho current pulse
height with the number of bombarding pulses is observed and explained in analogy to the known deterioration of luminescence under
ion bombardment. Thereby, tho higher dolerkration constant for
tho conductivity can be understood, (auth)
O I /
O I '/
•
ELECTHIC FIIOLD DISTRIBUTION IN GAI&IA IRHADIAT2D LSAD .
GLASS
• •:' •:
R.C.Hudson,R.A.Y/eeks
(Oalc H i d g e )
'.
In: PRNL-3213 « Solid State Division Annual Progress
Report fov Period Ending August 31)1901 .lo.Covo.lena
Crystals and Glasses.
31'f
Field i s calculated supposing incidence of a "beam not
accompanied by secondary electrons»
HIGH D03B 1'ttOTOIT IKÍATXUTI0I7 0? ALKALI HALIDES
A.E.Hu^heBj'O.Poolcy
'
J.J'fcj-s.C, Solid State 4_,lÇ63(ir/l)
Aton En .Ties, Kstabl. Ka.t. Do v. Div .JIarvrcll, Berks.
44535
RADIATION-INDUCED CONDUCTIVITY IN POLYJIEHS:
POLY-N-VIN'YLCARBAZOLE. Hughes, Robert C. (Sandia I.abs.,
Albuquerque, N. Mex.). IEEE (lnst. Klec. Electron. Eng.), Trans.
Nucl. Sci.j NS-18: No. 6, 281-7(Dec 1971).
From Annual conference on nuclear and space radiation effects;
Durham, K H. (20 Jul 19711. See CONF-710709.
Experimental evidence is given which indicates that the yield of
charge carriers excited by a given dose of x rays in thin films of
poly-N-vinylcarbazole (PVK) is dominated by geminate (initial)
recombination of the ion pairs. The yield as a function of applied
field gives a very good fit lo the theory of initial recombination
developed for gases by Onsager. Two competing mechanisms, the
Poole—Frenkel effect and track recombination, may be rejected
on the basis of the fleid dependence. A comparison of the charge
transients in PVK with other organic materials is given along
with a discussion of the possibility of trap modulation of the mobility In PVK. The role of three different kinds of carrier r e combination, bulk, track, and geminate, is described in terms of
the experimental results expected for each of them, (auth)
"XI (L
I
\
3(7
'
10313
GKMINATK RECOMBINATION OI1 X-RAY-EXCITED
ELECTRON--HOLli I'AIKS IN ANTHHACENK. Hughes, H. C.
(Sandla Labs.. Albuquerque-, N. Mex.). J. Chem. Phys.i 55: No. 12,
S442-7(15 Dec 1971).
A recent controversy Is discussed concerning the relative
importance of geminate and track recombination of charge c a r riers excited by ionizing radiation in single crystals of anthracene.
Data are presented that strongly support the geminate recombination hypotnusis for bulk excitation by x rays in the 50 to 500-kuV
rnngo. In agreement wilh the earlier work of Kepler and Coppngc,
it is found that it requires about 2700 eV to create a pair of charge
carriers in anthracene at an applied field of 10 kV/cm. (:<ulh)
^
6 Í l>
uero carried out 'i.-ith a
Fo'betrou,6C0 kcV.^ivitij 3na puluos.
Electron trap-.-in^ lifotirno v;as a «cut
5o i:âcro-occ.Ã;nlk reconbination cocíT.
for t,íi.i:iuas iis about 3i"-}.0-6 ciTi3/aoc.
18974
(SC-RK-720813) KLECTKON-HOLK CARRIER
DYNAMICS IN SINGLE CltYSTAL QUART/.: EXPERIMENTAL
RESULTS AND APPLICATION TO QUARTZ GAUGE PROBLEMS.
Hughes, R. C, (Sandln Labs., Albuquerque, N. Mex.). Dec
1972. 26p. Dcp. NTIS.
Charge-carrier generation by pulsed x rays and carrier transport In fields from 10' to A > JO'' V.'cin were investigated In single-
'
._
Q } vf
crystal quartz. The photoconductivity is found to be practically
independent of the angle of electric field to the crystal axes, and
the carrier lifetime in bolh synthetic and natural quartz crystals
is very short (less than 10 nsec). The average carrier mobility
during the short lifetime Is determined to be on the order of 0.1
cm 2 A' sec, which Is lower than predicted for electrons in quartz.
It Is shown how the photoconductivity can be used to predict the
magnitude of the space-charge buildup In the Sandia q.'iartz gauge
subjected to intense radiation environments and that lhe dynamics
of the intrinsic charge carriers are insufficient to explain the
shock-Induced conductivity observed in tiic Sandia quartz gauge
in certain high-shed; environments, (auth)
•
f
'
•
;i
CONDUCTIVITY IHDD0ED IN SOLID INSULATING MATERIALS
v
G.C.Huth
General Electric Company Aircraft Nuclear Propulsion
Pepartraent,Paper no. 58-33151958 (TLB 15 981)
Reports on radiation-induced conductivity in
,
ceramic insulators at elevated temperatures and dose rates
ofi-io4 to 10° E/h.Time effects are also discussed.
f
" • - • [ -
"••
%
^
•
f
:
•
'
3 20
041000 Hvolby, J. (Radium Centre, Aarhus (Denmark)).
Depth dose near the surface by fast electron
irradiation. Measurements with thcrmolumincscence
dosimctry.
Madsen, C.B.; Liden, K. (cds.). Proceedings of the
sixth conference of the Nordic Association of Clinical
Physics. Stockholm. Acta Radioiogica. 1972. p. 60-62.
Acta Radio!., Suppl. no. 313.
depth dose distributions; electron beams; irradiation;
lithium fluorides; mev range 10-100; polystyrene; radiation
dose distributions; thermoluminescent dosemcters.
—
? 2f
CP GAMliA fiADJA'i'ION ON TIÍ3 CIÍH1ÍENT-VOLTAGE
CIÍARACTiUHlS-íICS O1-' AU'HUUOKlTE FILMS
Hadiat.Kff. 1,2,133(1972)
Current-voltuce curvos aro shown before ana after
irradiation.'i'hc current for a given voltage decreases with
increasing doso,approaching a saturation value when
the integrated dose approached about 6xlo7llad.At a fixed
temperatva?o, the higher the trap concentration created
by radiation the creator the removal of traps per unit
tiiaej and saturation ia reached when the rates of
trap removal and introduction are in dynamic equilibrium .
A theoretical treatment of the effect is given.
3'22
~
ELEGTiilC GOKDUCTIOlí OF 3!WLUJIA'T3J> PGLYfiTHYLElffi
1.1. Ioda, k. Ho saki, V. Shinchax'a
J.Phys.Soc.Japan 1£,11O3(1263)
Hcports measurements on temperature influence-on YtlG of high
density polymers,e.j> polyethylene,after electron irradiation,
for exposure doses of 3,l!35and 45 I--R and 2 LleV electron enorr&v
A hyaterosis effect is observed.Conductivity during the first
hoating is ).;ucli higher than for non-irrauiated specimens. At a
temperature near tiio raelting poiiVG the crystalline regions of
different specisiens, conductivity decreases within a narrow
tcr.pcruturo range by a. factor of about 10. 'Phe decrease io
irreversible; during the coolins period the covidv.ctiv.ity
rci/.ainrj lower then during tiie first heating.iAxrin^ a siibaoquent
second heating it is only slightly lower than during the previous coolin;.; roriod. It is concluded that charco carriers crc;,tec
in polyethylene by irradiation are captured in crystalline
regions, tnrt not in Giaori^houa ones, their thermal release
contributing to electric conduction of irradiated po
ni).
EFFECT OF IIIGII-ENF.UGY RADIATION ON ELECTRIC f
CONDUCTION OF VARIOUS COPOL.YMEHS CONTAINING j
POLYETIIYI.KNE.
.
I
M. Icd.i, Y. Yaniuda and U. Shlnohera.
Eljclrlcal liiaulalion, Buck Hill Fulls, Ponnyslvania, 1S65 (WashingIon: N.iüoml Academy oi Sciences, National Rüscnrcli Council, 1006).
pp. 103-0.
Tho spoclmcna used were çopolymcrs comprising polyethylene
5071
323
I
32f
i
and various iiercciitsçco of other polymers e.g. polyvlnyl acetate,
polyprojiylcnc and poiyelhyl incth.icrylatc. irradiation was done
with pamma-rays of 5 mocarad from Co* 00 at room temperature
with a dose rale of 17 x W rad/hr.
11. N. Basu
A D3CAY PHOCaSS O? SUSPAC3 BLEOERIC CilARGBS ACKOiiS
K. l e d a , ü . üawa,U. Bliinohara
Jap.J.Appl.Fhys. 6,793(196?)
After corona chxa'k'ing, sample is transferred to shielded
room whore surface potential decay is measured.keeultss
l)",ihen initial field B o is less than a few hundred heV/'cr.i,
lnY versus t show linear relation meaning exponential decay.
2)ii"or higher initial fields decay is not exponential and
its rate is increased.This leads to crossowsr between curves.
Postulating instantaneous charge injection and movement in
own field the following relation is obtained:
V *fr Vv - f/i Vt Jid^Jt
in apparent agreement with results.
'
\
• DECAY PROCESSES OF DIFFERENT KINDS OF SURFACE
ELECTRIC CHARGES ACROSS POLYETHYLENE FILMS
M. Ieda,G.Sawa,R.Takeuchi
Japan J.Appl.Phys. 8,809(1969)
It is found that the charge decay is
influenced by the type of charged particles
accumulated on the film after it has been exposed
to the discharge from a point corona. Thus it
depends on polarit, initial field, and Op/X, ratio in
the surrounding atmosphere,
3-25
OP 'íB^PüitÀíUIÜS pjü-àiA liíiVJJlATIOIT AlíJ C H Y S T A L L I J T I T Y
Oil BECAY KíOCESSES OF bÜtíFACIi ÜÍLJJCGJEIC CHAliGHS ACROSS
Li. Ioda,H.Takeuohi, G • Suva
Jcp.J.Appl.Ehys. ^,727(1970)
Reporto measurements irith various gases at different
temperatures and different dose rates.
.
I
3-27
Conf.El.Insulation,October 23-25(1972)
ITtl.Acad.Sci.,Mtl.Bee.Council
ELECTRICAL CONDUCTION OF IRRADIATED
POLYETHYLENE AFTER ANNEALED
M. Ioda and G. Sawn
Nngoya University
K. Kitagawa
Glfu Technical College
Nngoya, Japan
Japan
3-28
The electric conductivity is known to change upon exposure to high energy radiation due to the production of
excess carriers during irradiation and the occurrence of
chemical and physical changes. To discern these two
factors, the electric conduction current was measured of
gamma-ray irradiated low density polyethylene which was
annealed after exposure near the melting point to annihilate
the excess carriers. The conductivity of the polyethylene
between 40° and 110°C was found to increase monotonously
with irradiation dose, while its activation energy varied
in a complex manner. The sample which was irradiated
and annealed in vacuum gave only a small increase in conductivity. This observation together with infrared absorption spectra of these polymers suggests that the presence
of oxygen during the chemical reaction may account for
the observed increase in the conductivity. A study on the
sample doped with a surfactant also has been made.
1
026084 lkcjiri, Tadao (Fukui Univ. (Japan). Faculty of
Engineering). Hie elfecls of gamma-ray rmllnlion
on tlie electric properties ol C|ioxy resin. (In Japanese).
Zairyo. (Jan 1972). v. 21(220) p. 45-50.
additives; breakdown; cobalt 60; electric arcs; electric
conductivity; electric potential; epoxides; gamma radiation;
hardening; medium temperature; radiation effects;
temperature dependence; time dependence.
w
• }
*
j•
•
1
054428 Ishikaiva, H.; Ishibashi. M.; Mogi. A. (Fujikura
Cable Works, Ltd., Tokyo (Japan)). Radiation
resistance of plastic material for cable, 1. Application to
low noise coaxial cable for nuclear measuring instruments.
(In Japanese). Fujikura Densen Ciho. (Jan 1972). (no.45)
p. 75-83.
aromatics; brittlencss; carbamates; chemical radiation
effects; coaxial cables; dielectric materials; dielectric
properties; dose rates: electric conductivity; elongation;
gamma radiation; irradiation; photon beams; poiycthylcncspvc; radiation doses; tensile properties.
33(?
CURRENTS W PLASTIC 7WSUL4TORS AND THE
OT GMNA-MX ZARAWAWOfr
3.IáesT,Urai
Chem.High Polymers 20,583(3963)(in Japanese)
.
(
i
„ ,
"33/
87
I
57777
PHYSICAL CHARACTERISTICS OF DIRECT-CHARGE
DETECTORS. Ivanov, V. I.; Kulakov, G. V.j Mukhaneva, G. I.
(Inst. of Engineering Physics, Moscow), pp 381-90 of Advances
in Phyfiicnl and Diologic.il Radiation Detectors. Vienna; Internatiomil Atomic Energy Agency (197Í). (In Russian).
Kroin Symposium on new developments in physical and biological
radiation detectors; Vienna, Austria (23 Nov 1970). See STI/PUB269; CONF-701112.
3-3"?
The results of studies on the physical characteristics of directcharge detectors ("radiation elements") desired to measure
gamma- and neutron radiations are presented. Data on the relationship between accumulated charge and lhe form, material and
thickness of electrodes, and electrode spacing are discussed. The
influence of space charge on the upper measurement limit is considered from a theoretical viewpoint. Detector sensitivities calculated on u computer are nlso given. Various aspects of the practical application of direct-charge detectors arc discussed, (auth)
Paper deals vith vacuum detectors. At
high, dose rates the space-charge formation reduces sensitiv.it;.',this being
due to very-lovr-energy secondaries. The
effects of chamber air pressure are
discussed.A current reversal ocurring
at low pressures might be due to the
Ohmart effect.
'
f
C:..v.acTüiiisi'ica OF miacT-ciiAKGii IOTÜ
V . I . Ivanov, (j. V. Kulalrov, 0.V.K02I0V, B. b. Salaualiha,
A. y. Go ric3ic-.ro v
In:Dcsii.ietry in Agriculture,Industry,Biology, an! Ieiicino.
S;/i,ipo3iu:.!,Vienna,17-21 April 1S72.IA3A ,Vion:aci. (lS73),p.663
JjoBcriboü thoorc-tical and experimental characteristics of
behavior of vaouuKi Cowpton detectorc.jjiaousüion covers
effects of geoMotrical and material parameters,an^lc of
incidence end energy of photons, and sensitivity. Kxncri^ontal
data on the quantum efficiency of different nutoriale r.nd
the electron spectrum distribution in the ener^v ratine
up to Eoi;;e koV are investigated.
DBTBH'.lIliATIOH OF FIELD DISTRIBUTI01T III DI33LECTEIC
LIQUIDS BY THE "DRIFTING LAYER" METHOD
A. Jachj-m, 3. Jachym, "if. Tomaszevfica, R. Zi elihsky
Acta Physica Polonica .A39,44l(l97l)
The motion of a thin layer of ions produced by ionizing
radiation is used to determine the field distribution
in a highly insulating dielectric liq.uid.For the
application a thin layer 0.3 to 1 mm thick was produced
at one of the electrodes of the chamber of 0.5 to 1 cm
thickness. The layer thickness must be small compared
vith the extension of tlie region of field inhoraogeneities.
Its charge density must be low enough to allow one to
neglect diffusion, and its electric field.should not
deform the charge distribution in the liquid. The method
was successfully applied to paraffin hydrocarbons,cyclohexane,silicones and carbon tetrachloride.
r
310B4
PHOTOVOLTAIC EFFECT INDUCED BY X AND v
BAYS IN LIQUID-FILLED IONIZATION CHAMBERS. Jacliym A •
Jachym, 13. (Danzig Technical Univ.). Acta Phys Pol • A « '
No. 4, <t71-<l(Apr 19721.
During the lonlzalion of liquid or air contained between the electrodes of an ionization chamber there is produced a potential difference of the order of one volt which causes ionization current to
flow. In the case of chambers filled with liquid hexane, carbon
telrachloride and oclnmethyltrisiloxane the short-circuit current
reached values of the order of l<r» to 10"" A. In air those values
were of the order of saturation current of current-voltage characteristics, also of the order of 10"14 to 10"" A. The experiment
shows that the produced potential difference is induced by the bulk
photovoltaic effect of the motal-dleleclric-metal system and by
the surface photovoltaic effect, (auth)
,
j
"
I
CCvDTíüTlVITY OF HEXATJU TWITE GAIATA IRRADIATION J.V.D ITS
*
SIOiriFIC'Ati:-;,;, FOR DOSKiiTiiT
A. Johns j '.V, Jaoobi
Zs.f .iTsturforsohung £1^,1400(1966)
Primftry(oolui/i;-iar) and secondary(volume) recombination in
d i e l e c t r i c liquidf, i s discussed t h e o r e t i c a l l y in analogy to
e f e e c t s i n derifie g a s e s , The primary reconibination i s i n t e r preted i n terra?) of an expression for t h e recombination of
s i n g l e ion pp.irH given by Onsager;Jaffa 1 s theory i s found
to bo not a p p l i c a b l e . The moan escape p r o b a b i l i t y f o r iona
in hexone in the absence of an external f i e l d i s of the ordor
of 3/í and the mean e f f e c t i v e i n i t i a l d i s t a n c e of the ions
in a primar j ' noir approximately 80 m i l l i m i c r o n . Measurements
were mado with a p a r a l l e l - p l a t e i o n i z a t i o n chamber,for
d i f f e r e n t value» of e l e c t r i c f i e l d , e l e c t r o d e distfince, and
dose rate.Thfí p o s s i b i l i t y of a p p l i c a t i o n for dosimetry i s
discussed,
_.
i
'••/I
EXPERIMENTAL STUDY OF EFFECTS OF KLECTHOK IRRADIATION FROM
20 keV to 1 MeV OK A POLYETHYLENE,TEREPHTHALATE CAPACISOH- .
TYPE M3TER0ID DETECTOR
T.G.James,H.H.Heyson,C.S.Frank(NASA,Langley Station,Va.,Langley
Res.Center)
NASA-T1Í-D-3682.
.
\
Irradiation produced pulses which were counced in a satellitetype detection system.The greatest number of pulses were
observed at 77°K{liquid nitrogen temperature).The number decreased with increasing temperature,but pulses still occurred
at 363°K. They are believed to be caused by electron storage
and subsequent internal discharges. Electron dose rate varied
from 3.1 x 10? e/cm2 sec to 3.1 x 101(Ycin2 sec.
.
j
*l
•
J
«;
:
I
PIÍPTH DISTRIBUTION l-'SASURBMENTS USING
"\.
BOiM^RDMBKT-HNHANCED SOLUBILITY
C.Jcoji
Phva. S t a t u e S o l i d i ( G e r m a n y ) ,
•Vol. 2 7 , ne 2 , 5 7 3 - 7 (1966)
A method i s d e s c r i b e d which e n a b l e s t h i n ,
uniform layers to be sectioned off from
the surfaces of insulators and semicon[
duetors. I t i s based on the formation of
bombardment-induced disorder in a layer
)
of definite thieknops by low-energy ion
bombardment and subsequent dissolving the
disorder layer in a suitable solvent. The '
thickness of the layer thus cemoved after
«various times and" conditions of ion hombar
dment is determined for silicon and mica
I vising neutron activation, analysis.The method is "
applied for determination of depth distribution
of radon decay products injected by recoil from
a planar radon source into mica.
f
CURRIfllíTS IIÍDUCED IN THE DIELECTRIC OP I01TI2A.TI01I CHAMBERS
THROUGH THE ACTIO1Í OF HIGK-EJERGY RADIATION
H.B.Johns,A.Aspin,G.G.Baker
Radiation Research £,394(1955)
Reporte t h e p o l a r i t y e f f e c t i n connection i-rith measurements
with of surface i o n i z a t i o n chambers.
I BETA-A1I3) GAl-n-^-IiTCUCBD COIÍDUCTIVITy 11/ SEIIICOHDUC'TORS :
/ A^FLICATIOli TO CdS UEUi'ROlI DKÍECTCRS
R.'I 1 .Johnson, J r .
J . A p p l . P h y s . 41,4981(1970)
338
51813
BKTA- AND GAMMA-INDUCED CONDUCTIVITY IN
SEMICONDUCTOR: APPLICATION TO CdS NEUTRON DKTECTOKS. Johnson, Ralph T. J r . (Sandia Labs., Albuquerque, N,
Mox.). J. Appl. Wiys.t 41: 4981-91(Nov 1970).
Methods for determining the mobility-lifetime (JIT) product ofhigh-resistivity n- or p-typo semiconductors, using induced conductivity resulting irom high-energy beta and gamma irradiations,
are developed. The JIT product is determined, under conditions of
steady-state excitation, from the measured induced conductivity
and the calculated electron —hole generation rate g. l h e carrierfree lifetime T is determined from these results using the measured Hall mobility. For gamma irradiation, g is determined
from the exposure rate, density, mass energy-absorption cocfflcients, and radialion-ionlzatlon energy (c). For beta Irradiation,
gfi is determined for the caac of tonlzatlon resulting from the
beta decay of radioisolopes that are produced by neutron irradiation and that are randomly distributed throughout the semiconductor. gfi is determined from the radioactive decay rate, energy
of tho beta radiation, and £. The absorbed dose rates resulting
from these radiations are also determined. Gamma-induced conductivity experiments were performed using ccCo gamma irradiation on high-resistivity n-type CdS, CdSe, GaAs, and 'inS single
crystals. The measured HT products ranged from ~10~ 5 to 25 cmV
V; T varied from <v10'"0 to 10"*1 sec. Some reduction in /IT resultIng from high-temperature annealing of CdS and GaAs was also
observed. Beta- and gatnina-induccd conductivity experiments
P P beta decay and MCo gamma irradiation) were performed on
neutron-irradiated CdS single crystals. Comparison of these r e sults show that: (1) The fir products determined at a given dose
rate from the beta and gamma Irradiations are in very good agreement (within 15%). Thus, the theories developed for determining
g and g* are valid. (2) For samples which have considerable
neutron damage, (IT is very dependent upon exposure rate (or
absorbed dose rate), decreasing with increasing exposure rate.
This is in contrast to samples which have minimal (or no)
neutron damage, where very little dependence on exposure rate
is observed. (3) The (JT product is also dependent upon the conductivity or Fermi leycl position. For irradiated high-resistivity
crystals (IT is 1 to 6 cmVV, and T is of the order of tens of msec.
However, for irradiated low-resistivity crystals HT is larger by
a factor of ~ 102, and T is of the order of seconds. The dependence
of jiT on the excitation intensity, defect concentration, and Fermi
level position in neutron-damaged samples results from sensitizing centers associated with neutron-Induced defects. The concepts
developed here have resulted in now techniques for measuring
ncutron (luences using electrical change? associated with induced
radioactivity in semiconductors. Gamma-induced conductivity
i
provides a valuable technique for "calibrating" these detectors
(i.e., determining the JIT product), (auth)
-v
,
J
1
;
:
•
.
;
I
!
:
f
j
I
j
j
'
39725
CADMIUM SULFIDE NEUTRON DETECTORS:
ANNEALING OF RADIATION DAMAGE. Johnson, R. T. J r .
(Sandia Labs., Albuquerque, K. Mex.). IEEE (Inst. Elec. Eleetron. Eng.), Trans. Nucl. Soi.; NS-17: No. 4, U-19(Aug 1970).
A new method for measuring fast-neutron fluences using CdS
has recently been developed. The technique consists of detecting
induced conductivity resulting From the beta decay of radioisotopes which are produced by the neutron irradiation. In previous
studies of radioactive decay effects in these detectors it -was
necessary to correct the conductivity data for effects associated
with radiation damage (defects). In this study, electrical changes
associated with neutron-induced defects have been minimized by
annealing the detectors at 300°C before measuring electrical
changes resulting from radioactive decay. The measured conductivity following annealing is just the induced conductivity
from bela decay, and no further corrections for radiation damage
are required. These results also confirm the accuracy of the
previous correction procedure, and show that differences in the
radioactive decay rate constants and the rate constants determined from the associated electrical changes, which have been
observed for some detectors, are not necessarily due to errors
introduced by that correction procedure. A brief discussion of
some of the general characteristics of CdS neutron detectors as
well as a detailed description of the annealing experiments a r c
given, (auth)
'
j
j
j
f'
:
•
I
\
l
\
-> J O
O
í£
ÜJLEOTllülíIC TüAlíSFOliT Ilí IHSULATIli'G FILKS
W.C. Johnson
IEBE Transactions ITuol.bci. US-19,lio.6,33(1972)
lievicw paper diacussing the follovring topics?
Trapping properties of localised s t a t e s . Space-charge
limitation of current. Bulk-trap-limited ciirronts. a)íloppií?õ
conduction "b) Poole-Frenkel
ei'foct. c)'PuianGlling emission
(field ci.iisGior.iJfroia trap» 1 . Ionic conduction.
;
r
TT{A"i'Si:jiT iL-DlATXOi; jJFFJiC'i'S Oil L-.LiiÜTrtOKIC CVúPOlfiZTS ASW
S-L'lCOliLOUGTC'.r !;• ".iVICi.S
I). 0 . J o n e s , F . J . H o l d , iV.^.C'napinjD.J .Kamifian,^.K.V/ylor
AS ^O?.1J.2(iQ I9/4/19Ó3 - Jiâttolle i:om.Inst.Tíad. Effects Inforimvlion Canter
r
3847G
SELF-POWKRED NEUTRON DETECTORS. Joslin,
C. W. (Reuter-Stokes Canada, Ltd., Ont). Nucl. Eng. Int.;
17: No. 192, 399-401(May 1972).
The application of self-powered neutron detectors in nuclear
power reactors is described. Details are given of their use incore detectors in flux-mapping systems and in full-power control
and safety circuits. The advantages of platinum detectors are
discussed, and reference is made to recent interest in detectors
for fast-flux environments. (UK)
344-
r
K
2221
ELECTRICAL CONDUCTIVITY O? y-IRRADIAtED
SuUD MONOMKHS AT LOW TKMPEHATU1IE. Kadoi, ltajime;
Tabata, Yonclio; Oshima, Keichi (Tokyo Univ.). J. Phys. Chetn.j
74i 3962-8(29 Oct 1970).
The electric conductivity of solid monomers irradiated by y rays
at —J9(j°C was measured during temperature elevation and compared with that of nonirradlated systems. For the nonirradiatcd
systems, peaks in the current—temperature curve were observed
at the transition points that were determined by x-ray diffraction
and thermal analysis. Activation energies for nonirradiatcd systems ranged from 0.3 to 1.2 eV in the higher temperature region.
At low temperatures there were pronounced differences between
the irradiated and nonlrradlatcd systems, although a negative current was observed In both cases. In nonlrraulated systems this
negative current might be explained as rising from the depolarization of the oriented permanent dipolea, whereas In the case of i r radiated systems it might result from the annihilation of charge
pairs produced by the irradiation. In the latter case, the average
migration distance of the electron was estimated to be about 100 A.
(auth)
-j •/ _
D*f Ç)
25623
(UCHL-73493) TIME-RESOLVED X-RAY DETEC'
TION USING MOS-C DETECTORS. Kalibjian, Ft.; Ciarlo, D.;
Mayeda, K.; Boster, T. (California Univ., Livermore. Lawrence
Livermore Lab.). 10 Feb 1972. 7p. (CON1---72030S-2). Dep.
NTIS.
1
From Scintillation and semiconductor counter symposium;
Washington, D. C. (1 Mar 1972).
To develop a fast x-ray detector with a memory, we have performed experiments with metal-oxlde-semtconductor capacitor
(MOS-C) devices. For time-resolved recording of the x-ray pulse,
a linear array of detectors is uniformly Irradiated while the elements are sequentially biased at At time Intervals; significant
positive charge trapping occurs in each element of the array only
during the period At when the high field bias is applied across the
dielectric. Detection of 10-ns resolution has been recorded. Timeresolution is presently limited by the bandwidth limitation of the
bias strobing method, (auth)
____
'
.
AT
it I
I
|
I
/'THE SPFBCTS OP H1GH--BNJ3SGY KADIATION OK INSULATORS.
I Progress Report No.2, September 1, 1962-February 23, 1963.
Hartmut P. Kallmann (New York Univ., Hew York) Apr.1963,
Contract DA36-O39 SC-S918O, 6p.
The influence of lattice vibrations on the annihilation cr^-ss
sections of positrons in insulators is sunanariaed. At constant
volume the annihilation rate increases as the mean square
amplitudes of the lattice vibrations so that at high temperatures, the temperature coefficient of the annihilation rate
becomes inversely proportional to the elastic constants of the
lattice.
'
The effects of x-rays and ultraviolet light on the polarization of anthracene crystals in contact with conducting glass
, electrodes are investigated. The polarization obtained after
60 min of x-ray irradiation is 5i» of the ultraviolet polarization. (lí.Ví.R.)
c
ri
?
'.KMERGY TRÀÍJSFKR DURING THAH3IKHT JIUCLSAT? PULSES
•"H.P.Kallmann
Progress Relit .No, 3, March 1,1963-August 31,1963.ííew York
Unlveraity,Dep1-.,of Physics. Nov.1963» Contract
DA 36-039 SC-S938O s 29 p.CFOTI, Si.60 cy.
High energy radiation effects on insulators are examined. Ionize.
Ion:i zation,excitation, and chemical changes aaauKring.x. are
considered•Radiation extends from soft X-rays to gamma raya.
Experimental methods are described,
/
.
.
' '/ •
1 ENERGY TRANSFER DURING TRANSIENT NUCLEAR PULSES
j H.PiKallmann
New York University,NY,Radiation and Solid State Lab.
Semi-annual report no.1,1 May-31 October 1964.
Contract DA í>8 043AKC00129E,Proj.lCO 145O1B11A
A method is proposed for the reduction of the radiation
response in cables and oapacitors.lt tries to neutralize the
charge accumulation at interfaces. The insulator should
'have a sandi.lch structure,composed of several layers each
of -which having a thickness smaller than the extension of
'the width of the charge layer' (0.25-0.5 mm).These layers
should be separated by thin mylar films or the like.
/
•
"
'
r
"
/
-
ENERGY TRANSFER DURING TSAITSIEHT 2TOCLBAR PULSSS
.
H.P.Kaliman
.
.
-
•
-
"
-
Final Rep..March 1,1962-April 30,1964 (New York Un.,
Radiation and Solid State Lab.) May 1964 .Contract
DA-36-059-SC-89180
Effects of X rays on insulators are investigated without
applying external el.field during irradiation.Anthracene
crystals are electrically polarized by light or X rays
with an external field applied while the effects of
the X rays are investigated only in the internal polarization field of the crystal.This method shows that
X .rays applied concommittant with external field produce polarization persisting for more than 1 hour after removal of radiation and field.This polarization
developes also with blocking electrodes. .Similar effects,*
can be produced in polystyrene and influenced by X
n
irradiadiation.
*
I RADIATI01I-IHDUCED PHOTOCONDUCTIVITY IN SILICON
/ A• M - R a i m a , J . C . C o r e l l y
—- S a n t a -£tL- C o n f e r e n c e • o n r R w l t - a - t i o n - ; j f {"-eotè-in
_Hc-mi.coiiductprs._Sairta l' 1 ^ New_MG.xiço J __5j = 2_Pçtober 1_96J.
" (AÍÕD'".:' Cbnf." 6 7 - 3 6 9-0 3.0. W
"'"
"^"
P h o t o c o n d u c t i v i t y induced, i n z o n e - r e f i n e d S i l i c o n doped
\ a t l i A s , P , and Sb h a s been s t u d i e d a f t e r bombardment
uith
badment uit
1.5 1'ieV and 45 to 50 i'J'eV electrons. For "ihe high energy
electrons an "energy band" extending fronf 1.5 micron to
4.5 micron is made responsible , for the 1.5 MeV electrons _
well defined energy levels dominate.
/
I
DKCA'Y 0 ? BUra'AGB POTSliTI/J.S III I1IBULAT0HS
K.i:.I'.anazawa»I.P»33atra,H. J.Viintle
J.Appl.Phys. 44,,719(1S72)
The potential decay of surface oliarged insulators is
analysed,assuming movement of injected carriers(excess
charge) and presence of thermal carriers.General solutions
are obtained. The case where the injected carriers never
reach the grounded electrode is also discussed.
1
.- 3-5-3
_
~
—
DEEP TRAPPI1TG KHIBHATICS
K.K.Kanazawa,I.P.Batra
J.Appl.Phys. 43,1845(1972)
Paper discusses charge transport in an open-circuit system
for the case of dea trapping in a single trapping level.
Carriers are introduced through photogeneratioti by higly
absorbed illumination. Pulse and continued injection
are discussed. Recombination and field-dependent photo generation of carriers play no role in view of the short
penetration depth of the radiation. Field-dependent injection
is treated, -where injection is proportional to the mth powei
of the surface field.
/
THE ELBCTHIC COIIDUCTIOIT IN E230QÍS n-HEXAIIB UIÍDSR
. ULTPJ1.VI01.3T A I D GAl-^lA RAÜIATIOlíü
K.C.Kao,A.M.Phale,J.H.Calderwood
T r a n s . K i e c . I n s u l . 2^,108(1967)
THE EFFECTS ©F GAiaiA BADJATI01T OK HIOTOCÜHBBNT-VOLTAGE
CKA11ACTBHISTICS OF CdS Films
E.C.KaojA.Sadhu
.
R a d i a t i o n E f f e c t s 14,279(1572)
Univ.tianitoba, El .Bng.iiept. ,1'iat .Res .Lab.
f
*>ü°
\
\
•
CHANGES IN THE COliMJCTIVm OF HO1ILI1JKAR RESISTORS
OF BLACK SiC UliltfJii THE ACTIO1Í OBn GAl-iMA. KADIATIO1T
lI.Kashkoxdceev,S.Ribarov,K.Krezhov,V.Todorov
Dokla&y Bolgarskoi Akadenii líauk 24,35(1971)
I
I
; oi" energetic electrons
L.Katz,A.S.Peiifold
Rov.Jiod.Pjiys. 24»2c'i(l<!52)
All observed data co\ild be represented by the
r e l a t i o n ^ r>^ 0 cr& - ._, \
iii
7
o
o
R,, = 53OE «106 } 2.5 *13 <u20 LIoV
,°2
°
II i n m{j/cra
/
f
\ PEIÍtíTRATIOlI Oi7 ELBCTHOKS I1IT0 MTHRíiCBlíE CRYSTALS
J.Appl.Phj'S. 42,501(1971)
'
Penetration depths and ener^r loss profiles of electron beams
in anthracene crystals are measured by observing cathodo—
luminescence assuming that luminescence intensity is proportional to the absorbed
electron energy. Current densit.y
was about 10 raA/cm2,energies between 25 and 40 UeV. The
method vras first used by Vf.Ehrenberg and D.E.IT.King,
Proc.Phys.Soc .,London, 81,751(1963)
.
_
. .
...
...
/..
CGHPÍfiW í>I0DHS:fH30RY
AHD CONJECTURES
J.G.Kelly
. . . . . . _ . . .
Sandic-, Laboratories,Its.Rep. SC-H3-67-S55 (^iarcii 1968)
Discusses detailed theory of Corapton dielectric diodes
under the assumption of a perfect dielectric«Several
cases,including a cylindrical detector system irradated by a plane wave parallel to the axis,pancake
systems(where traasition or barrier effects are important) are discussed.Space charge problems,breakdov.-n,
and conductivity currents are .mentioned.
49246
(ORNL-TM-2986) THE DEVELOPMENT OF
RADIATION-RESISTANT INSULATORS. Progress Report,
July 1, 1967-July 1, 19GÜ. Kelly, M. J.; Parkinson, W, W. (Oak
Nidge National Lab., Tcnn.). Aug 1970. G4p. Dep. CFSTI.
The apparent electrical conductivity of high-resistance plastics
was examined from the standpoint of dielectric relaxation processes as well as steady-state conductivity. The observed, timedependent conductivity of high-purity polystyrenes, commercial
plastics of lower purity and of the copolymer in use for dosimeters
can be accounted for on the basis of dielectric charging and low
values of conductivity, both varying w^l» the polar nature of the
base polymer and the impurities. During Irradiation tlio conductivity increases greatly depending on the dose rate and decays
after irradiation with a time dependence related to the composition of the specimen. To be suitable for dooimetor uso, tho r a diation-induced conductivity must decay rapidly, to values below
10~" mhos/cm in 10* seconds. Tho ourrently used material, a
copolymer of styrene and or-methyl Btyrono (Corox 250B), was
found to have unusually rapid decay of conductivity following Irradiation. By polymer fvactionation and by varying the synthesis
ingredients, tile chemical species active in reducing conductivity
was identified as sulfate chain ends arising from persulfate initiator in the polymerization recipe. Styreno homopolymers were
Bynthesized with sulfate end groups and shown to have as low conductivity as the copolynier. Polymers with sulfate end groups and
(NH4) cations showed low but erratic conductivity and polystyrenes
having end groups of moderate polarity have lower dielectric
charging prior to irradiation and some reduction In postivradlation conductivity. Methods are proposed for development work to
exploit these possibilities for improving plastic insulators, (auth)
\
COMPUTATION OF ELECTION TRAIISPORT IN DIELECTRICS
E.Kemied,y,l.lCohlberg'
Tran3.Amer.liuc.S0c. _ U , l I o . l , 407(1968)
Effects of electron irradiation on dielectrics,
in particular range reduction by space-charge effects.
CHARGE CARRIER LO33IL1TY MW
AMJUtAOiEB
R.G.Kepler
Phys.Rcv. 119,1226(i960)
I'iiOUUCTIOli Hi
)
ICi: ÂHD RBCOLZBITTATIOIT CP ELECTRONS A1O HOLES III \
R.G.Kepler jPjl.Coooage
Phys.Rev. 151,610(1966)
Measurement \riih pulsed 600 keV X-rays are reported.
Average energy to create an externally measurable
electron-hole pair was found to be 3 000 V,number of
carriers being temperature-independent between -25°C
and +2500.Recombination coefficients were determined,
taking into consideration that under an external field
recombination takes place in a vqoume which decreases as
carriers are swept out. The high value of W = 3 000 eV
indicates that only a small fraction of the primarily
created electrons and holes become free. These are
those for which the electrons have enough energy
to vocer the minimum range necessary to escape the
potential of the hole.
.
3*62
TO:-
Oi- 1 '•.IT. ••• 71I-LO":TS A t ' 0
Conference! on 'ílechrical Tnsulcitien and
i>ielectric Phenomena, Pocono --taiior,
Ponnyr:ylvanie. I960 (Washington: Kational
Academy oi Scionccí'3, ÍO&V)^. 7-9
I t i..f. r<hown that the nu who r of car r i err?
generaí.ecí by hiah onargy -V-'-rayf-: in
a nth ruco no i s r.ivill *»a c-.-in -be <::«. lor .1 Mice!
on the bf.;si£? ot o. jsiwplo rddel, "h- only"
conrt.lt.lor; necosrsary for the v a l i d i t y of
tho tcioCiol i s that the charco carr.iarc have
to havo a very nhori.-. moan free path» The
model then shov3.c5 hz rtircctly npolic-nble
to poly;,-'P.rs thereby iraKing i t pov.:i±W.o tò
calcu3atG the number o:i c a r r i e r s cronted
in almost any high energy environment, r
Bulletin -II..MJ;-a.3oo.12,i:o.3,3C0(15-70)
'
•
DM 2
'
Radlotlon Induced Conductivity In Polyethylene
Tereththalato and Polystyrene* R. 0, Kepler, Sandla
laboratories — Electrical conductivity produced In thin
films of polyethylene terepbttmlate (Mylar) ond polystyrene by three nanosecond vide x-ray pulses from a
600 kV flash x-ray cocaine has been studied. The current
1 observed in these experiments is proportional to the I
•1
1
intensity of the radiation pulse, decays approximate^
os the reciprocal of the time after tho x-ray puloo, tnd
is very temperature dependent. Free carriers produced by
the radiation ore apparently ell trapped In tines lose
than a few nanoseconds and oil the current observed
appears to result from the relaxation of ionic species
created vlisn the carriers are trapped. The results are
consistent vith the hypotheslL that the nuaber of
carriers generated varies with the ujplled electric
field as expected for low mobility naterials.l
4669
OPb
t
RADIATION EFFECTS IN COAXIAL CABLES.
Kerris, K. G.; Berggren, C. G.j Carter, D. B.j Spehar, G. G.
(Hughes Aircraft Co., Fullerton, Calif.). IEEE (Inst. Elee.
Electron. Eng.), Trans. Nuol. Soi.; NS-16: No. 6, 264-70(Dec
1969).
From Conference on nuclear and space radiation effects; University Park, Pa. <7 Jul 1969).
The results of a systematic study of the interaction of cable systems with ionizing radiation fields are presented, with a view
, toward achieving a fundamental understanding of the effects, governing radiation induced cable signals. Tho study led to the construction of a physical model which was used to obtain a quantitative description of the dominant processes involved in the
interaction. The model is sufficiently comprehensive to permit
the calculation of the current induced in the conductors of a coaxial or triaxial cable 6ystem (or. indeed, almost any other system
of conductors separated by an insulating medium) for any combination of incident photon and electron spectra. A number of experiments was performed to support the calculations. The validity
of the model ts demonstrated by showing that the experimental
data verify the theoretical calculations, (auth)
Response of RG-3(RG-213) Trias Cable, i n Electrons/lhoton cnT 2 )
-cm of cable: 10 keK Sreiusapafilunc; r-,7.4xl0" 4 r „
A
10 Lev •"rercsstrahlung ^lècxrons -d.87x10
10 MeV ürensstrahlim£ Total -1.63x10-3
5 keV Brensstr-ahlunc; Photons -1.24x10-3
5 Lev BrernsstraMungSec.Electrons -'5.14x10-4
5 MeV Breiiisairahlung t o t a l -1.76x10"^
lie-jative response indicates tliat electrons are collected by
center conductor.
o / «r
OQ /
FrrT-r.'HATiou oy UTOii-yrraiio:.
ELECTRO:: ÍEUÜS J:T \UT3B.
l!.V.Yci:üi;TÍc
11 >; r.-.IÍov. 1^2,1^(1:? 65)
^
Deveio:: s> tlic theory bv.ccscl on an equation "b;- Lcvis.
Th o theoretical curve nhcnrs a i:::i::i:.;u.'.:(:Lr_ the d i i í o r o n t i c l
CTCcírvai) in r.^roenent -..'ith oy.i orii.ent. A r a t h e r
narrou re-ion of charge? aocrjnulatiot: e:victs. I'he
difference bet wen charle aeyocition }'rofilcs ;;ÍK! r.bcoritioii C"-vr- ?.r.. ar.-ll ;;inco the directional d i s t r i b u t i o n
of ••:(. c:M-!nr.r; o].ootr-. r.s ic l . . r j r l ; i ^ o t r o p i c . At
tHDr.ll doptho a ,?. narrou region of i'0/;itivo aluirão ia
foviitl. At 20 J.GV a 3!.:;ill ai.ionr.t of ^ror.isctrahlunj i s
fomul,in Ki:ito of the lov atomic ü.av.bor of the c
AMMA-RAY IK3UC3D CONDUCTIVITY IF POLYETHYLENE COAXIAL CA3LS.\
Kichinosuke, Y. and Danno, A. Japan Atomic Energy Research
Tokyo. J, APPL. PHYS.v.^1, p . 7 3 4 - 5 , Apr.I960
The e l e c t r i c a l c o n d u c t i v i t y changes i n a 3C-2V-type polyethylene high-frequency cr '42 r Í3^ °Hble are reported f o r c o n d i t i o n s
of high dose r a t e s of^umma r a d i a t i o n . The dose r a t e s ranged
from 4 . 2 x 10^ to 1 x 10° r / h r and p o t e n t i a l s , of 0 V> 1000 v
at currents of 1O""H to 10~^ amp. Relations between the induced
currents and dose r a t e s g i v e s t r a i g h t l i n e s of s l o p e 0 . 6 3 except
for zero v o l t a g e . The d i r e c t i o n of the current f o r V = 0 i s
reversed to that for the v o l t a g e supply, r e s u l t i n g i n a g r e a t e r
v a l u e foi- the s l o p e .
/
jACCUMULATION OP ELECTRIC CHARGE IN GA1OIA-IRRAÜIATED SHIELDING
jWINDOW GLASS
.
'i
R.Kikuchi
j
Nuclear Bngineering(Tokyo) 11,11(1965)
j
D i f f e r e n t t y p e s of window g l a s s v/ere i r r a d i a t e d w i t h °Co
radiation,at room temperature,dose rate of about
6xio5a/h and t o t a l dose of up to 3x 10'R.Non-irradiated
conductivity as a function of temperature, sroi thermal
depolarization currents,and thermoluminescence were measured.
Currents were measured for unidirectional and for isotropic
irradiation.Several current peaks were observed and con —
elusions about trapping l e v e l s and charge carriers drawn.
SENSITIVITY OF A COMPTON DETECTOR
R.M.KlooDper,V.A.Madsen
LA-1990,Los Alamos_ Sci.Lab.,New Mexico #955
Paper discusses behavior of a vacuum detection
system.
^
',
;
!
'
>70
37/
ELECTRICAL POLARISATION IN LEAD-SILICA-GLASS AFTER
X-RAY IRRADIATION
G.Kneohtel,A*Soharmann
Zeitsohrift f.Angewand-te Physik 12*389(1965)
Measurements were carried out after irradiaton with
90 kV X-rays and doses be'tweenSxlO^ and 2x1-0'^ R. The
irradiated samples were rapidly heated to temperatures
between 8O0 and l60° C. Discharge currents were measured .
Por temperatures u p to I400C current • reach a maximum
within a few minutes and subsequently decreae while
the temperature is kept constant. For higher temperatures
a current reversa] is observed and for the Viighest
temperature at which measurements were taken the current
ha.3 apolarity opposite to that for lower temperatures.
Effects are interpreted by assuming that due to photoand Cotnpton effect a space charge field is built up.
Heating release^ 3ti electrons trapped in color centers
which move i-. the polarization field. The reverse current
at high temperatures is interpreted as a positive ion
"37»
BEHAVIOR OP CAPACITORS EXPOSED TO HIGH-ENERGY RADIATION
M.Kobale,G.Seebacher
Electronic Engng. (GB) 42,,no.505, 52(1970)
ENERGY DEPOSITION BY ELECTRON BEAMS
E.J.Kobetiob.,R.Katz
Phys.Rev. 170,391(1968)
The product of two empirical relations, for the practical
range r and for the transmission probability p of normally
incident electrons is differentiated to yield an Eq. for the 3 7 3
energy depostion. Combined with 6-formulation this provides
theory of spatial ionization energy about the path of a
rapidly moving ion. If 3 < w <2p HeV is the electron energy,
A=5.37x10-4_g/om2 k e v B=O.98l5,C=3.123xlO-3/keV (in Al) t
(l) r = Avr£ l-(B/l+Cw2_7inicrogram/cm2 keV. Electrons of rang
r which have penetrated a foil thickness x have a residual
energy W which is found from above Eq. as the energy to go
to the residual range r-x. The residual energy W may be
written as Yi(r,x)=w(r-t)»The energy transmitted through
a foil is approximated by the product of transmission probability p and residual range H. For monoenergetic electrons
(0.01-3 MeV) one has/
,
P=/~l+exp(-gh)_7 . S l+exp/~g(x/r-h.}_7 f
I
I
where p again is fraction of incident electrons of energy w,
range r, transmitted through absorber thickness x. In absorber of thickness x, atomic number Z.mass number A, one has
g=9«2 Z-2 + 10 ZT2'2 and h=0.63(z/A)+0.27.
PHOTOCONDUCTIVITY IN Kl.KCTJUCALLY
ST11KSSED DIELKCTIUCS
jf~ '$
111. J . Kofoi<l ami II. V. Cleva
Boeing Scientific Research laboratories
Seattle, Washington
Conference on Kleetrioal Inquisition.October tt
1'ationul ,i.cader.iy. N a t i o n a l Research Council (/<f73)
Application of a high electric field to a thin sheet of
polyimule insulation produced a large increase in conduction current when the polyimide was illuminated with
visible light. Without irradiation, this material is an
excellent insulator. The conditions under which the theory
allows photoconductivity to occur in insulation are examined. In the experiments described here the electric
field was produced by depositing in vacuum either electrons or positive ions on the exposed top surface of a
dielectric sheet which had its lower surface resting on a
plane electrode. Some initial results are presented.
,
OK PENETRATION OP GAKMA RADIATION THROUGH HETEROGENEOUS
BARRIERS
A.M.Kolchuzhkin,V.V.Uchaikin
Atoranaya Knergiya 2^,442(1968)
t
^
MEASUREMENTS OF ELECTROMOTIVE FORCES INDUCED I N DIELECTRICS
IRRADIATED BY X-RAYS.
Kolomo/tsev, F . I , , Yakunin, A . Y a t / Sviridenko, O . N .
Nauch. Zap. Dneporopetrovskii Gosudarstv. Univ., 72, 3 (1957)
—
The ernf induced in polyethylene insulation and its temperature variation were measured
from -30° to +70°C. It obeys an activation law. At -30° values up to 105 V were
obtained. The temperature dependence of conductivity was also measured,
/
THU EFFECT OF ElECTKOWOTIVE FORCES PRODUCED IH
W IRSAWATIO» UpCiJ THB BEHAVIOUR OF TKS TKPUCEP CVRgttaT
P.I.KolomoytseVjA.Ya.Yôkunin
Fiaika 1,127(1958)
Izvestiya vyssliikh uchstnykh Zavedenli,FiKika
(Transactions of Higher Educational iHSixt'iass Establishments.
Measurements are reported which indicate that irradiaion of
dielectrics by X-rays and gamma rays produces electromotive
forces which superpose on the applied field c-r.i can r^ach
hundreds and thousands of volt. It is believed that they
?re due to dxffszaKSEsxinx transient effects sris occurring
and the front and back surfaces of the samples ,where the
density of the absorbing medium undergoes a sudden change .
I THE-EPFECT OF EUF'S ARBISIHG IH DIELECTHICS IRRADIATED
1
BY X-RAYS Ul'OlT TUB BEHAVIOR OS1 THIS I1IDUCED CURRENT
P. I .Kolomoy tsev, A. Ya. Yakunin, Izv.Vuzov
Bulletin of Higher School Physics
£,127(1958) (USSR)
Reports production of emf in X-rjty irradiated insulators.
f"
'
•' IOKIZATIOJÍ CüaiítíNTS IN DIAMONDS III CAS3 OP 5OO-1OO keV
ELECTRON BOIÍBAHDMÜNT
E.A. Konorova, S.P. Kozlov, V.S. Vavilov
Fiz. Tverdogo Tela jB, 3 (lS>66) 3-8
It is shovm that with fields exceeding 10 v/cm the linear
dependence of the product of the drift velocity by the carrier
lifetima on the magnitude of the electrical field is not
strictly obeyed and that at 10^v/cm this value (which one the dependence or the product ?) has "been observed to he
saturated» The results obtained have beer, interpreted in
terms of the theories that predict the mobility of carriers as
a function of the field strength
5 calculations -are in
satisfactory agreement with theory. In natural diamonds the
electron lifetime has been proved to lie in the 10
—
10~ sec rangeQand,to be determined by the nitrogen content if
it exceeds 10 ^cm" .
'
1EFFECT OP HIGH-MEHGY HADIATION OH ELECTRIC CONDUCTION OP
JPOLYETHYLENE
M.Kosaki,Y.Yamada,U,Shinohara
Comf.on Electrical Insulation,Cleveland,Oct.1964{CONF-769-8)
Measurements are.reported,results being represented as graphs
i è & ^ against inverse temperature. For polyethylen
giving caKituciè&í^
B03istance deoreaseses with dose at room temperature, but near t
the melting point the decrease ceases and resistivity gisx
jumps to the pre-irradiation value» The radiation effect can be
EEHEXiEi eliminated by annealing; the "jumping" is explained
tm by recombination of radiation-induced charge carriers upon
melting.Polypropylene gives continuous curves.
/
/
X-RAY I1JDUC3D PHOTOCONDUCTIVITY 0?
0.Kramer,1,'i.Ghalla , J.Canfield
J.Chem.Phys. 4^,1346(1966)
3á*D
r—
•
'
'.7ith a beam fully penetrating the sample induced conductivity of crystals
has been mea-surcd as a function of dose
rate,field strength, and temperature.Currents increased
linearly with dose rate and field strength. At 630 V/cm
oharge production was about 7 x 1 0 ~ 1 2 C/cm2 rad.Currents
increased vdth increasing temperature exponentially,
exhibiting two different activation energies, one below
;
j
»'and the other above 25O°K.The activation energy decreased
with doso rate. The nobility-lifetime product for the carriers
covild also be determined.
j
j
!
j
•i
f
GODIVA II IlffiA])lATIOir OP SEwIRAD
S.Kronenborger,H.M.Lurpiiy
IIP 7576, December 1$58
3*2
101
IRRADIATION OF . .
SElilRAl) AT T1IE GMÍEIÍAL ATOMIC LIIiEAR
ACCELERATOR
S.Kronenborger
US/1SRDL-TR-2070, May 1 9 5 9 .
.
OACTTC'AI, FATJ?:/:.TJOM RO8ÍM3TP.Y IN Tiis U,S ./•.^••'Y.
K r o n o n b e r ' ' ' , S t a n l e y (Army l . ' l o c t r o n i c r : CoiPffcjnri,
F o r t ^ o r i F o u t h , : T . J . ) H e a l t h P h y e » , 1 4 : 41-A
(; f ?-n, 196fi) •
The army ir:- i n t e r p r t p i in t h e ior-imstry
proble-nn acseciat^ci with t s c t i c n l v:«rfr-rc; in
vhioiv FWSII t<5.c'<"i.c?.. 1 nv."i o-^.r ws?noíis ttii^ht ~oo.
visei'. Thore/'orc a t ? c f - i c a l closii'.iotrir ir- requirec?.
rncf";í::it5Tí nc ^r^th ir?"p/r.n Í r;c neutron
to^'^)
ÍOFO ^^'"ÍTÍ:"op.tir? 1 h^vo
dosir^.tor w i l l s a t i s f y
r^cí^^í 1*5^Í"Í t o
ICÍC^l^'^o„ h £\\^'\T\Y.
a l l of
the
requirements
J of a tactical doserneter.Physical principles,cnatruction.
and performance of Radiacraeter IM 185 are discussed.
IK LiP CRYSTALS BOUBARDED BY ELECTRONS
J.Appl.Phys.
)
j
i
j
;
31,4722(1966)
Breakdovm induced by bombardmerit with 1-2 MeV e l e c t r o n
v/as i n v e s t i g a t e d , beam i n t e n s i t i e s being betv/een
lxlO-*-? and 2x10-^^ e l e c t r o n s / c n i 2 . Sparking was observed
during and a f t e r bombardment. The brakdown l a y e r contained
the e l e c t r o n range plane(corresponding t o t h e e x t r a p o l a t e d
r a n g e ) , but the middle plane of breakdown p a t h s ( i . e ,
where t h e maximum p o p u l a t i o n of breakdown p a t h s v/as found)
was l o c a t e d beyond t h e e x t r a p o l a t e d r a n g e . I t i s
concluded t h a t e l e c t r o n s t r a g g l i n g played an important
r o l e . The number of breakdov/n p a t h s i n c r e a s e d w i t h dose
and with discharge p e r i o d and decreased with time ÍEÍLEJIEE
between i r r a d i a t i o n and breakdown i n s e t . D e n d r i t e s c o n s i s t e d
mainly of s t r a i g h t paths,sometimes accompanied by curves
p a t h s , e s p e c i a l l y a t branching points.The paths,which were
clearly visible in the microscope due to total reflection,
were hollow channels left by the evapoeated material.Material
brought out along the paths were found attached to the
„.——surface where the path exii was found.Structural alterâTiõns
such as foruation of Li netal colloid and r.:olten material"'.'
yere found near large breakdow. channels,indicating
instantaneous electrolysis with heating and subsequent
"t
H
cooling.
)'
i
!
I
j
\
ÍOL
EFFUCl'S 0? THE PriOíOlí BOI^ARJJLKLÍT OF líap CKISTALS.I.
LiEAaüKJM.rtíaT OP !?iUi AVERAGE PROJECTED RAHG3
K.Kubo
J . P h y s . S o c . J a p . 33., 1401 (1972) (Nov.)
:
!
i
f
'.
3fffc>
ELECTKOLYTIO BREAKDOYJIT I l í PROTOIJ-BOKBARDSD L i F
CRYSTALS
-.
"
K.Kubo
J.Phya.Soe.Japan 21_, 2599(1966)
DIBlíáe'££ie BSJüàKaBwil tüíSSa 1.9 MeV proton bombardment
3*7
was studied. A negative discharge figuro wa3 observed
s i m i l a r to the conventional e l e c t r o l y t i c - t y p e point to
point discharges. In correspondence to what happens with
electron bombardment i t was believed t h a t a p o s i t i v e space
charge wouldbbe formed which when discharged would r e s u l t
i n a positive Lichtenberg figuro.However the a c t u a l figure
was not l i k e a p o s i t i v e one but more l i k e the e l e c t r o l y t i c
breakdown due to conventional point to point discharge
(socalled negative s u r g e ) . I t i s believed that the proton
f i e l d produced by the l a y e r of trapped protons a c c e l e r a t e s
electrons 2>resent in the crystal-^These will cause irapact
i o n i i z a t i o n of ions or atoms leaving a t r a i l oi p o s i t i v e
space charge behind which shields the proton f i e l d and i n h i b i t s further electron a c c e l e r a t i o n , t h u s preventing the
Lichtenberg typo breakdown which depends r on instantaneous
n e u t r a l i z a t i o n of the space charge field. i'he breakdown
Pig.coni3ists of random and<100/'paths with l a y e r s of p r e o i p i t a t e d Li metal.
f
P.1IETRATI0IT OP K0N03ííi33Gi:TI0 ELECTRONS
DIELECTRICS
THROUGH
•
J.Kuczera
Kukleonika ,Uo,7-8, 503(1966)
i'easureraenta are reported for the energy range between 0.59
KeV to I.I85 MeV,and for several dielectrics(paraffin,
polyethylene, ,epox.y resin,,methyl polymethacrylate,
cellulosç,cellulose a c e t a t e , , and mica). üiEBrfcEEHsxxErHxx
As the beam source a beta spectrometer was used.
|
i
j
Í
/OS
52315
POTENTIAL MEASUREMENT AND STABILIZATION
OP AN ISOLATED TARGET USING ELECTRON BEAMS. Kudirka,
P. E,; Crawford, C. K. (Massachusetts Inst. of Tech., Cambridge).
Solid-State Electron.: 35: No. 9, 987-92(Sep 197?.).
The construction of very large arrays of electronic components
on a single semiconductor chip implies a need for new methods of
component testing. The presently used contact pads take up too
much space. The method proposed uses primary electron beams
to excite low-energy secondary electrons which are used to sense
surface potentials. Tho primary electrons are to be allowed to
strike only very small diameter metallio contact areas on the
interior of a chip, In an environment where surface electric fields
are oarefully controlled (i.e., no exposed insulator surfaces).
Data are presented for a preprototypo system using a mockup
target and a single large-diameter electron beam. Two operating
modes, potential stabilization (corresponding to voltage signal
Input) and potential measurement (corresponding to voltage signal
output), were demonstrated. Accuracies better than 100 mV were
observed for both modes using a 5 kV, 10"6 A, primary beam. If
the method could be extended to multiple small-diameter beams.
.
•
*"*"
3<>A
Ov>y
It could be used to simultaneously inject several voltwre signals
while measuring outpi • signals from extremely smaL .. Icroclrcults, (auth)
ií.KusüOEOV
(falo Al to, Ca. £4 304)
IJ3EB Transactions Wucl.Sci. :íü-17,l(;o(lS7O) N°Q>
An extended nonoecncr^otic bea;.: of photons incides
normally on a v.lafce several electron ranges thick. In
the paper the nui.it;or of electrons emitted ins calculated,
including P^oto-and Coi.ipton electrons and Au^er electrons.
Calculation is dono for electrons er.itted into the haifcpace to the ri^ht of the plate,into that to the left, and
the difference of the tiro,applicable to ch:i.rye transfer
between tvro closely spaced plates of the s;.:..e material.
Calculated yield curves are ^iven for fluoi-eccont and
AXVJQT distributions for Au aj; ^'OkeV, as function of
plate thick.icss bct-.;oer: 10~' and 10~^,cia,and electrontransi-.ort yield for Cu and Au up to 10 lieY.
I
f
|
{••
S'P.KvekjG.l.
Properties of MOM tunneling detector are presented and
parameters influencing operation are discussed.Theory
of operation at small and at large signals and experimental
results are discussed.Polarity reversal at large signal
levels is predicted theoretically and observed experimen-
.__..
-201
'
2819
(1,015-342) EFFECT OK HIOH ENEIIGY RADIATIONS
ON INSULATING MATERIALS. (Lnlwratolre Central des Industries Klectrlques, Fontenay-aux-Roses (France)). Jun 1970.
75p. (In French). Dep. NT1S (U. S. Sales Only).
Methods of estimating the pcrmnnent damage, in terms of the
variations in the electrical and mechanical properties, suffered
by insulations and cables subjected to irradiations are described.
With the aid of the results obtained, the lifetimes of the materials
were determined, and an attempt was made to define an acceptable dose limit. Six groups of different products were studied:
(1) basic insulating materials, in the form of fijms or sheets,
such as polyethylene^, polyamides, nnd licavy molecular plastics; (2) impregnating varnishes; (3) Impregnated cloths; (4)
enameled wire; (5) wire and cables; and (Cj laminated copper for
printed circuits. Two radiations were used: 1.3-MoV gamma
nnd G-McV electrons. (France)
3Q 2
•* » *.
•
f
13327
(LCIE-3C4) INFLUENCE OF VARIOUS FACTORS
IN DETERMINING TIIE VARIATION IN THE ELECTRICAL
CHARACTERISTICS OF CAPACITORS EXPOSED TO GAMMA
RADIATION OR ELECTRONS. (Laboratoire Central des Industries Electriqucs, Fontenay-aux-Roses (France)). Sep 1970.
34p. (In French). Dep. NTIS (U. S, Sales Only).
The changes In the electrical characteristics of several types
of capacitors after exposure to high energy radiation were investigated. In order to obtain a better understanding of these effects,
the Influences of different parameters of the radiation, 'he environment, and the component geometries were studied. (France)
PRODUCTION OF LAHGE ELECTRIC FISLDS IK DIELECTRICS BY
ELECTRON INJECTION
H.Lc.ckner,I.Kohlberg,S.V.Nablo
J.Appl.Phyo. _36,2064(1965)
Targets of Lucite and polystyrene were irradiated by
1.5 KeV electrons until the occurrence of spontaneous
breakdown.Framing camera pictures of the fluorescence ,
zone shov/that the regions steadily decreases until ±ke
breakdov.n is observed. This indicates a decrease of electon
electron range due to chacgge buildup and increase of
an' internal space-charge field.Fields of up to 6.3 KeV
are inferred. It is pointed out that the potential within
the dielectric might exceed the accelerating potential.
ELECTRICAL DISCHARGE I N SHIELDING WINDOW GLASS OF MULTIKILOCURIE CELU
4
J N O . 1, BUILDING 3029.
Lamb, E,
Oak Ridge, Tenn., Oak Ridge National Laboratory, Dec. 1960. 10 p. (Report CF
no. 60-12-13).
1
An electrical discharge in a four inch thick pane of shielding gloss produced a typical
branching pattern. The gloss had been subjected to the gamma radiation from 13.000
curies of Co°0 during the five days prior to the discharge. The cause of the discharge
may bs explained by the entrapment of Compton electrons which would result in an
electrical field gradient Sufficiently high to exceed the dielectric strength of the glass.
The danger of electrical shock during the cleaning of an irradiated piece of gloss would
existi
-2 Q -J
" "°
"
L
PULSEI) BUCLHAR KADIATION EFFECTS OK RESISTORS AND CABLES
C.P.Laficaro,iV.SohlQssQr,J.NewiDerg
ECOtf-2?45
-'
(Army Electronic Labs.,Forth Monmoutb.,N.J.)Dec.1964,35 p . S . 0 . 5 0
Transient response waa measured during the p u l s e . BtítettXE
Behavior of d i f f e r e n t cables TOMEX was compared.
.
STUDIES OP A330£i*H01T 0? KIOH EITERGY ELliCTKOlT
BEAKS
'
39A
;
J.S.Laughlin
In"Syraposiiua on High E n e r ^ Blectrons",lJ.Y.Springer, p. 11
Penetration ofelectrons
_
. . and charge deposition
profiles are measured in an experiment in vfhichactack'
of alternating layers of conducting and non-conducting
polystyrene was bombarded
with high energy electrons.
Kessari's theory iraa roughly --infirned.
I
18958
ENEHGY REMOVED 3Y DELTA SAYS FROM FINITE
VOLUMES IN PASSAGE OF CHAHGED PARTICLES. Laulainen,
N ; Bichscl, II. (Univ. of Washington, Seattle). Nucl. Instrum.
Methods; 104: No. 3, 531-9(1972).
In the passage of a charged pprticle through matter, the energy
lost by the particle, in general, will .not bo the same as the energy
retained by the material. Calculations of the differences caused
by escaping electrons (delta rays) are presented for two experimental situations, but the methods used can be generally applied;
e.z., 50-MeV protons in a carbon foil 1 mg/cm 2 thick would lose
11 keV; 107c of this energy loss would escape from the foil in the
form of kinetic energy of delta rays. An escaping delta ray would
appear only for about 1 in 25 protons. In a rough approximation,
for protons in light elements, on the average, an energy amounting to 50 eV per MeV of initial proton energy is removed by delta
m
|
EL. GTRO1TIC TRAlTSl'ORT III AMORPHOUS SILICON FILMS
P.G.LeComber, i .}í.õpea.r
Phys.Jíev.Lett.
(
XI IITDLJCED CUlffiEÍTS JJC30SS AUO, /ILLS
R.S.l.ee
I3E3 Trans.irucl.Soi. 173-17,,47(1-970) M#6
i
'í
1
•t
Pilus of AlpO, ccLiid'.iiched between thin >:.etr.l electroJ
vrero inv.diated '.rith continuous radiation fron a CoGet X-ray tube of 35 kV.Currents versus; tine and uo
voltage *.rore recordei during i r r a d i a t i o n . Induced ch
trapping effects are discussed. Ileasureuents -.rith d.c . and
a . c . seen.s to allot.* to distinguish bet;ree:i electron c.nd
{jole effects.
RADIATION EPFECÍÜ Olí PBliKOJiii.JOCTiilG ííàTiOJJAljS .
I.Í»c:í.'Januta
Summary R e p o r t . Research, avid Deveiopiücnt Laboraio: 1 •;• . Gleiv:c;
C o r p o r a t i o n . 19<\'">
AD 6^5 o51
Materials used were barium ti tanato-type raatorialn.jíof.ctor
radi;i,tion and °°C'o radiation were urscd, Mer.'.surc-!:ieiita
included charge release during radiation exposure,
surface charge mt>asurementf.s,piezoelecjfcric property on.
Several effects can be interpreted in termo of Coi.-.i'ton
current. In forroclectr.icc additional factors interfex'e,however.Thene are a pViotovoltai.e effect,contribution
bf the polarisation state of the system to tr.o (••.Vtr^e
release, a surface charco layer, and a possible anomalous
charge release.
DIKLECT!?.!0 HÍ3ASUHÍÍ.IEKTS IK SOME IRRADIATED CLASSES
E.Lell, (Ba.usch and Lomb T;ic. Hochestor NY )
^
Ridgo Rational Lab. )
1962 Coni'oronce Radiation Effects on Glass}IlochosterjWY 1962
Suramary Paper 3io,ll
Effeoto of 1.5 MeV electron and Co gamma i r r a d i a t i o n on
d i e l e c t r i c relaxation spectrum rind i n t r i n s i c e l e c t r i c a l
conductivity of high p u r i t y s i l i c a , l e a d s i l i c ate glasOjphof:phoric g l a s s and pyrex are i n v e n t i g a t e d .
.
WPPKCTS OP IRRADIATION ON POL.ilíIZATION CUilHEIITS IN L10AD
SILICHTE GLASS
E.Lell ,H«A.'.ieo3:o
Bulletin Ara,Phys.Soo.,Series 11,8,(4) April 1963,P.34O
60
"
F'or
Co irradiation,the conductivity of a lead silicate
glass was measured as a function of voltage,sample
and temperature.
RADIATION EFFECTS IH QUARTZ,SILICA AND GLASSES
E.Lell,N.J.Kreidl,J.R.Hensler
InsProgress in Ceramic Science,J.E.Burke
e d j t
Pergamon Press (iasnàEH New YoEb) ,Vol.4, p . l (1966)
Survey a r t i c l e including e l e c t r i c a l and e l e c t r o s t a t i c phenomena induced by p a r t i c l e and gamma r a d i a t i o n .
NEUTP.CH AKP GAMMA RADIATION EFFECTS ON DIELKCTRICS
E.G.Linden,C.P.Lascaro
USAELHDL-TR-2323 (Army
my Eloctronics Res.and Develcoraoni
Forth í.ioninouth,NJ U3
)
3A)
Mecsurerr.ent ofi effects of pulsed radiation on d5 e l e c t r i c s
such as F;sbestos-f •Hbric phenolic, asbestos-fill eô phono"! in,
paper phenolic laminate e t c . Exposures have no significant
permanent aftereffects on d i e l e c t r i c properties,.
if)"''
t U£
J. Li n dmy or, J . ];.. Hay noll.clsj
()
!
i'hc charge div-Lr:Lbu'tio'A in debei'/.unoil "Ir/ r.iocicurins
lhe change in ohurjo dv.irji-üy i n th o üi inversion l c
as the o;-:idei j.o t,rc.'.du.-i'U.y etched off.
THE STS'i'EIi T^avU-OXIMO-SILlCrUM. (l-iOS)
J.Lindi.iayer
Ph.l).TJiecip.,Toc!mictil University Aachen 1968
The charge d i s t r i b u t i o n in the oxide i s determined bj'
stepvdso etching of the oxide, i'ieaourcreent of the
channel conductivity then allows to reach conclusions
concerning the amount of charge remaining i n the oxide.
407
1UJJIATIC:Í A1TD G/JIS-kK^AL Ii:raiíAOi'lG]ÍS IV. i:
J.Linü!. :aycr
IWHS T r a n s a o t i o n c i i;y-ltí,"l(l f -.Y'i ) ji-o.6
SiIIiJ12>l"ÍG GLASSES
.T. Lindner
I'uclcoiiics Data. Sheet lTo.27, Vol. ló(l<5G)
Also reproduced in? Technical Glitue B u l l e t i n 170.103,
r i t t ü b u r ^ ; h , r a . , Pluto Glace C o . . Ono Gi'.tcira.v CCÜ"1. o r / i ' i t t t i
22, Petin., October 1,1963.
.
1
RAMATIOM EFFECTS OH INSrLATIOH-STATE OF TEE ART
V.J.Linne'bom
Insulation(L.ibertyville) 10,2l(l9&4)
'
THAKSIMT HABIATION EFFECTS ON ELECTRONIC PARTS
V.A.J.van Lin-t,RoF*Overmeyer,D.K.Nichols
AD - 623 904 (1965)
(Gen.Atomic San Diego Cal.,Special Nuclear Effects
Eep.No.GA 6534
Prompt and delayed conductivity i n Epsaoe mica,ceramic,
tantalum oxide,and Mylar d i e l e c t r i c s with various types
of electrodes xinder Linac i r r a d i a t i o n aere r e p o r t e d .
A theory of neutron induced BEHÉJíeiiiEfcfcjí i o n i z a t i o n
has "been developed which p r e d i c s t s l i n e a r r e l a t i o n between
conductivity and neutron energy deposition r a v e .
!
r
\
If If)
21507
RAUIATION-INUUCM) CUKRKNTS IN COAXIAL
CAMP'S van l.int, V. A. J. (Gulf ltadiaüou Tech., San Dicfco,
Calif.). IK li li (Iiial. Elec. Electron. Kng.), Trans. Nuel. Sei.;
NS-17: No. C, 210-16(rtec 1970).
From Conference on Nuclear and Space Radiation Effects, sail
Diego, Calif. Sac CONF-700713. •
The effects of gamma and neutron radiation on coaxial cables
should be described aa a current due to kinclicnlly moved charge
and a conductivity. Simple models, using Known cross sections for
gamma iinrl lu'iilrim Interactions can lie used to calculate the
amount of i-harge displacement. The rurlialion-induced i.onductanco of a cable can also be estimated from data on the dielectric
material. Kxperimcnlal data frequently show larger initial response limn the estimates. The observed current is proportional
lo instantaneous dose rale or flux, but the proportionality factor
is a generally decreasing 1'uhetiun of duse or fluence, even
changing signs in some casuf. The anomalies .-.ingest lelaxation of space charges created In Hie dielectric by the manufacturing process or by physical motion, (autli)
388
I0NIZATION RADIATION EFFECTS IN INSULATORS
AND INSULATING PARTS. Van Lint, Victor A. J.: Harrity,
John W. (Gulf Radiation Tech., Gulf Energy, and Environmental
Systems, Inc., San Dlcgo, Calif.). 1EKE (lnst. Elec. Electron.
Eng.), Trans. Uleo. Insul.! EI-G: No. 3. lll-i3(Scp 1971).
^
Tile effects of ionizing radiation on insulator parts are discussed
as being the results of four associated phenomena: conduction,
charge transfer, space charge buildup, and air ionizaticn. Techniques for estimating these effects under come circumstances of
interest are described, (auth)
I IS
V. A. J . van ] :i :;t ; -7.",!. ücirri t;
i ; i . l n ^ : u . t i o n 701 6, :"o.3>343 ( l - ' ( l )
•
;
;
T
a
j
B
i
i
i
i
p
u
L
^
B
i
E
c
^
c
:
r
w
V/^
^
r
C
3
i
,
7
0
i
r
i
:
r
s
c
i
ro
\
;plELiiOT>:IC3
' '
JIÍ.Little, J.Ottesen, P.K.Childc-rs
IEBB íranoactions líucl. Sei. !T:i-IL6,;To.6, 250(156$)
Reports tiro experinents on Lucite to see vhat effect the prir.ar;.- ~/1S
stepped charge uigiit have in v;ork tiith HeV piilDei electron
beards. In the first experiüient, cilery.' deposition profiles were
neaf.;ured ucing calorir.etric techniques, l-'.eaaured profiles irere
compared with Llonte Carlo electron transport code calculations.
Shapes of profiles \iere not much different ths.11 for cavii/alent
thicknece conducting; materials, but integration resulted in
anomalous hi^h bea» energ;/ fluenccs. This effect wcu r.easurcd b;
measuring electron beam QIIOTJ\- fluences through equivalent con ductiny and dielectric absorbers. It irac found that the dielectric has an effect upon the electron beur.i spatial distribution.
?or discussion two j.iOucls uere used: a) Ho trapped charge b ) Dielectric breakdovm Model in vhich charcen build xxp to a specified breakdown potential where all charge is released, and re mains zero for the rest of the calculation. The increased bean
energy absorption is interpreted as beam focusing pro
/Oi
on—ÍW"its incid-Mit GXib^Q- doiisitios \.::cli higher than the
ciioi\.;- flueuceo i::civ,jurod t;i tli the covjdv.cti.'ij cariou ealor.ir.eter
BGÜI.I focuoin;-; I.'::;J iirver.t.vy.ted b~j ^ tv.c^.-iii^ offocts of uioüact r i o .-.ibjorboru or; the rciáiul i n t c n ü i t ; ' àiotrilíivbion of tjie
e l e c t r o n boarj» Ac the tiauhnoGO of thrs d i e l e c t r i c aboorLore on
top of "the ,7.ri:ij..lo i s inoiroa/jod, thej tiviiis.-ii-fte:1. finonoo La COIIOÜ ouhanccd ".ãtJi rcf.vc-jt to an ti^vixvaloit Al a'osorbor. A
posiji'olc ci^lí^n^tion ira c, Iv^d.lc.-up oi' |;o:;:i.tivo Í^^-ÜCC charco
i n "fcho Vali: oi' th o Eij.iylc MÍÜ.CJ:. taiKir; to »o\;-Lrí.lÍBO ti; o nc;r.~
t i v e G};uoo ch:.rL;o aoDociL'/ted irith. tiic cloclroii 'bc^u allo^.Lii^
i t s i..u.,;nc!uic 1'iGld force:.: to CÍ.VHJC :;o'J.f—i'ocuuiii,,;. A t h i n COÜdiiotin;; í.'i3.:;; ( f o i l ) OVCIO.Ü.;-; on t!ic froiit sarí't;cc uí" the
dicloctrio oli;..i;Kvtos the l!cur.i fo
t!ie liic-ilcot-vifj :!.'ocn
lín.-.ull:,- ci..olo: o d.
I
'
i;;^; e f f e c t ; . L.'otc t::í;t i n
i;o c^oxuiy.cj. tsiirfcoosi vrorc
\
- (1>$3-. 13147)
oi
o.roíci <•''•';í.actoir
opj.ivo c v i r í i t x o
ftliictroa bror-r^ow;? p u l s a s , ;>
í c ) n . ; e o i " t:jr/ipp
i ! i £ t h r i 3 o f c!3.sc
-;.)H'tí.ng '-'•ic-.;i fro-o . - . ^
oiroíc 1 . n x ' O i J o c c d ! ivni :•..•.::;, ÍI;ÍC! Í.VI>-> to.-K. -rr.i.\.r/{i
«"r-ri.^
rloni.'v: o.C a i o c t r o n l'.j:.-);>'-.(1.:::.;rj p n i s o n , .'v. .^vr'Ciu;
pcnoJii, uf.:s.c? f-3 tor-t f.ptc1!^/-?^;;, "wo;;-: y;3.?<.ÍÍ3 Ári
M contro.llec! t-.e; ipui."ítiitc l>^.":t s i n ' ; , v;.!.'cli Vir;
e l e c t r o n source íoriuntocl ;í.nr;icle 'Jlici hcrL siiii'.
volumf! nncl p n v s l l c l t o t h e p a n a i s . Tíis entire.
ar.«cniib].y was l o c a t e d i n s^lr-.rgo VECUU;:! chÍJ:V\>>oj:
held ? t approxini.~it-.oly 10°"^ t o r r . Tsraporfturs
V?CÍS verioS" o.nd c o n t r o l l e d from imibient to-g^o p
Principal tost r e s u l t s indicate pulnos vero of both
p o l a r i t i e s irith respect to the bias voltage of the
panel,pulso riso tino vas of tiic order of r.iicro-aeo.,
anplitudos raid polarity of brce.k&o-iai pulses are apparently indopondent of bias or loaa rcsi stance .Brea]:do;.".i
rate varied approximately inverselj' vith ter.peratiirc
and practically vanished at rooiri temperature.The
spectrum of breahdoim aniplitudco decayed rapidly \rith
amplitude, no pulses being observed {jreater than 2.7 Vi
\
Bulletin
1^,764(1970)
observed oxpfHniont.il results. It was necessary to
include in Ihis model contributions to tin: piezor-Gr.istivity duo to the temperature variation of the relaxation
time anisotropy as well ;::• the contributions due to the
presence of coiapensatina irradiation producud accejitors,
such as the silicon A-rentc-r. This nod<.-] wil] be
discussed and i t s predictions compared v/ith the experimental results.
BUO. 11 iph 10ncrRV.pcnhUy Rrspon_sv f.f Mate-rials
Usin^ lnu-ji.sr_jiola!_ivjs_lu_ K li-ctrun St rc.ims • - A.
MJTZÊT.1- KEAUGfC O. YÜNAS and V. W. SPKNCE.
Pliy»ics In'.vrnatiuna 1 Cn. -• Pulsed rc-L-ilivislic ch-ctrnn bt-ains willi - [ w o hundred kilovolt tm-an electron
energy at current d.-nsilifs up tti 100 kA/cin have been
used lo sludy material response to high energy density
front surface loiidiny- Diagi.nstics stict-t-ssfully used in
the rlertrim beam envirtniment include (a) a ballistic
pcndtiltun to measure total impulse delivered U' & sample, (b) quartz pressure transducers to measure the
early C ^ 0.5u9)' s t r e s s vs. time profile, (r) manganin
picKoresUtivc gauges to measure late lime (C lOus)
stress profile, and (d) streak and framinii camera photography of vapor and liquid expansion from the front
surface. Observations of mixed-phase phenomena a r e
discussed.
//cf
Work Supported in part by the Defense Atomic Support
Agency.
KLECTH1C
OF
P0LYV1J.7L
R . J . L u j t n , S.A.R.Lujân
Rev.i.:cxicana P i s . I õ , : : o . l , 5 7 ( l 9 » 7 )
The r e l a t i o n 'bc-tvreen "breakdown v o l t a g e and ro.cliatiou dose
vras i(iveG-li t ;:itoá with 1-VC fill:.;; f o r o l e c t r c n i r r a d j . a t i c n
i n tho. ran^-o of 0.6 t o 1.0 KeV and 0 . 1 to 5 1-irad. Uao of
elcctrcrri s p i n resonance teckiiicmec poi'uit to d o t e r u i n e ti;c
r e l a t i v o c o n c e n t r a t i o n of frco r a c . i c a l s i n the f i l i a c . T'he
r o l a t i o n r j h i p bohrecn t h i a c o n c e n t r a t i o n ana tr.o brofikcloT.ra
v o l t a g o and the v a r i a t i o n of eoiicont7'a,tior. vãth tir.e it.
discussed.
In'
Zr.f.i:
of
:xturroT '•':!, r-ii" V]».. 3 07'.' (1 ?6/ ; )
i";::i:ov.r!]. o"f "t!;in í3l.rrí'r.t:f-!! .-.•yo•"<•••; ov Do:: W . O T 1 - ;
urpj-!.-; :^T-^3 JciTi 1'• t v ^ n
s^'ii.i'
2=3 ;-r;1 ISO VrV,
The "boi.íixi-rdiní-; p s , r t i c l e r j lürodiico :: n d n c c d r u c i l o a c t :
i'hc ::icaijuro!..ents a r e c u r r i e d owt -.rith a "s;iavJ.ni;-<
method.
PHOTO-COiiPTOH CUrJffiiíTS III irULOUliDSU I.KDIA
C. J.I'iacCallum,T«A. U o l l i n
J.Appl.JPhye. U, IC78(1973)
(cf . D « l l i n )
The theory c o v e r i n g t h e .10 keV t o 20 KoV range i e based
on t h e f o l l o w i n g i d e a l i z a t i o n s i a ) kediura lionogenoous and
unbounded^ e . g . a l l i n t e r f a c e s a r o nore d i s t a n t ths.ii one
e l e c t r o n range (lO~4g/cra2 i n II a t 10 ko»V t o 10 g/cra2 i n u ,
a t 20 lieV. b)PLoton f l u x s p a t i a l l y uniform ovar one e l o c t r o n range.Thus p e r t i n e n t nonuniformity
given by r a t i o
off moüti
forward
e
l
e
c
t
r
o
n
range
Uy
photon
interaction
müt f
g y p
i c)
) Steady state,e.g.photon flux uniform in
oiifit J. ././ fi*
timo.KLeoírpn stopping tines even in KeV range are 10" °/q
whore P,density.- d) Jiluctron transport calculated taking
account of multiple-scattering angular effects "but using
osda, (continuoxis slowing down approximation).-llesults for
not current can bo applied as oourco terms for calculation
of electromagnetic fields generated vá thin, irradiated
dielectric-filled cavity.Wet current differences in differii
I
differing media determine magnitude of radiation-induced
charge deposited in vicinity of an interface.The forward
and backward currents in an unbounded medium are upper
bounds,respectively,for forward and backward eiaieuion
currents at vacuum/medium interfaces and play a role
in construction of empirical modelo of current variation
and charge deposition across interface.
^11^:31^-i1 KAOIATiCi: K?1P'SGJ}C, 12; C?:.'ICAi
tf.-^cIALS
'
F.l.'.Lacts, ^ . i l . G ' i l l
LA~J>C-li63ó
()ícp.j.oc Alt.i.oc í>cic:it .3-.-.o. ,V,o:i J.oxico)
Ti íe uoc of t h o p r o t o t y p e l-Jiuri/.òx o"1 o c t r o n iicvidií-.tor t o
circulate h i g à - d o t í o - v n t e n u c l e a r onvirow.iont i a di:jOML;í;aà.
The froe e l e c t r o n doiiaity produced is: o p t i c a l :..i:toT±v'Xti by
tl:e Eiachino bear1., and -i^^t ejected fro;;. & tyvical incident
proi.:pt-o!"!:ii:'-£1' i"iáiatio!i ' lux urc coujareJ.» An c:r.j..oiv:..Gntal
setup to measure the o octs of tro.ns:..iotsio:i of :;clüctei
nateriala i s described, and data obtained on t-lieao :.ato2ds.ls
are proÈionted. Transient or rcr:.;^-.v.ent lostj of transuicsion
Was observed in optical glauco and GJS-lCl fused ouarts,
but no effect iras «con in purified fused s i l i c a . Reflectivity
of front-surface a.Uu.dnu;:; and d i e l e c t r i c i.-irrors v:aa clno
chec];ed and no effects wore seen.
60382
ENERGY LOSS OF THE HIGH ENERGY ELECTRO**:
Belousov, A. S.i Malinovskli, E. I.; Kusakor, S. V.i Sharelko,
P. N. (Lebodev lust, of Physios, Moscow). Yadern. Fiz.i 16:
No. 2, 339-42(Aug 1972). (In Russian).
Tho electron energy-loss measurements within the 90- to 550MoV region and at 31 GeV were made. The experimental dKAlx
values are an attractive fit to the theoretical ones without using
radiative corrections. These measurements were performed at
tho 250- and 680-MeV electron synchrotrons of the J.ebedov Physical mstitute and the electron beam of the 70-GeV IHEP proton
synchrotron (Serpukhov), (auth)
/x')'~)
/**•
,
ÍJ Q <
7 Av
/ . '
S O L I D S lit T;;;O P H K
OP
A.l-any,
A.l-any, U.ftulcavx
Phys.Hov.126,1^00(1962)
Pr.X>er civec a ur.theiaatic treatment of the problem fnr
insulating und for conducting crj/Btalo. fciv'l.i.r.ied solutions
aro obtained
current and space-cheapo distribution
Lti.'l of injection fro::i ouo olootvcuui, the l a t ter
n^1 plac via an oküio cont&ot under an a p l i c a volta ge
pul o.Exact am.l.v t i e d sjoliitiour; ai-ejhoi.'ever, given i'or
the tiro lini ti.M;-; oasey of no trapy.ing ana of fu.r;t i-iri.ri.j.
r-pini; in inoulator.:J ax>pro:-:i;.:u.te coliitio n
"slovr" r
vcn
aro £,'i
valid for tivma larger than tiri^x the t r a n s i t
tii:io. 3Tiu:.or:ical Bülutiona are give 11 for chortor tinea.
20947
(T1D-1542G) KFFECTS OF GAMMA-ItAY IKRAUIATION ON FIVE PLAST1C-UONDED HIGH KXl'lOSIVK COMPOSITIONS. Mapcs, James E.; Schwartz, Frank B.i Kautman,
J. V. Kichard (Picatinny Arsenal, Dover, N. J.): liovy, Paul W.
(BrooWiavt-n National Lab., Upton, N. Y.). (1960J. 53p. Dep.
NTIS.
Declassified 19 Oot 1971.
The physical changes in five plastlc-bondcU high explosive
compositions induced bvaCo gamma rays were studied for exposures up to 3.5 x 10s K at two rates, 4.5 * 10* and 2 x 10s R/hr.
Some samples were given a single continuous exposure while
others were exposed in successive increments to the same total
dose and measured after each exposure. Diameter, length, and
weight v/erc measured, and volume and density were calculated.
Detonation velocity and plate acceleration capability were testei
on samples which have been continuously exposed. The explosives
studies were 9404 HMX/Nc, HMX/Kxon, KMX/Ps, KRS9 HMX/Kc.
and DATB/Kxon. (T.F.D.I
ELECTRON SHIELDING CODES FOR EVALUATION 0¥ SPA2E
RADIATION HAZARDS
B.W.Mar
Boeing Co.Rep.D2-9O414,AD-459,157(1963)
Boeing Report D2-9O414,June 1963
Theory of electron transmission in matter for electrons
produced at a given depth in a target, having f^Kinetic
energy and scattered at a given angle. The theory re —
fers to the case where electrons are produced by Coiapton
or photo-effect in matter and permit to calculate the
number of electrons which escape the target.
'•
AK
V,T.:.Í;TÍIOÍ;
Slb.üKOTjK; ANALYSIS " v or.'.".:J Vi.r-n?L.'.ò
j HUB!! i.-.vr Soionco and
A nomograph £or sisKtrranxio: number of electrons tr.-i.»K::ilttcci
an G.-ipreasion for tho differential enoj\f;y spectrum of tlic
pone try. ting elcoti-ons are dtivloped fro.: Monto C^vlo c:ilcu~
l a t i o n s , Kormo.l incidence i s oupoooed, o:>.lou] v.i.ion^. nro.
carrifid out for Oiff orcont naterií;'l.fi(j"íe,Al JFOJ/^JPIJ) and
f
l t
for
KK-x-KlEEtiiEK:.o l f lc ttr o n onor;:icrj in iho ran^-r- of 0,4 to
10 í.toV,Goi,;;->:>.r:ií-son with oxiM-iririiental rtr.tf. and so:;ic- p&hcr
criloulrttiona fjliow tlio tuothotj t o bo s a t i o f u o t o r y , 1)o:>-j
c a l c u l a t i o n a s.ro also niade,
A?7
r
j
t
SPACE-CHARGE LI.IIITED CURRJiTilTS IK OHGAHIC CRYSTALS
P.Mark,U.Kolferich
J.Appl.Phys. 33,205(1962)
Conductivity moasua^eraontes were nade v i t h 50 wicrom fiingie
ci'ys'talG of anthraconojp-tcrphenyl and q-tcrjolionyl euppliei
with acjueoua e l e c t r o d e s , o n e an i o d i n e - i o d i d e s o l u t i o n and
tlio o t h e r an iodide solution.The acceptor e l e c t r o d e forms
an oJimic contact f o r hole i n j e c t i o n and S0L cxirrents
can t o dravrn from t h e c r y s t a l . T h e theory of t h e steady
s t a t e and t r a n s i e n t c u r r e n t s i s developed. Hole t r a p p i n g
s t a t e s form an exponentially decreasing d i s t r i b u t i o n from
stbove valence band. I n p - t e r p h o n y l , hole concentration
i e about lO^V0*31^ a n < i mobility izlOr2 cm2/V s e c .
\
I0.NIZ..T10M CHAilBBBUjPHui) ü? POI-AHI'i'Y iii-'PIiCiSjDtmiVM POR
KLEtt.'ROD DOSIWiJriiY
B.L.arkus
IniliosiMetry i n AgricultitrOjIndustiy,Biology,and lledicir-e.
Syr^osivja 17-21 April 1972(Vienna). lASLi. Vienna (l973) 5 p.463
Two p a r a l l e l v.late chambors(phantom and e x t r a p o l a t i o n ) i;ere
constructed for electron dooinetry. They are freed oi the
polarity effect by xise of a new principle, e.g. diminished
collector voluuie. Origin and behavior of the polarity
effect are discussed and measurements for 5 a "d 15 lieV
electrons are reported.
i
DEfiJlilllllATIOlT OP CARPT.iiR MOBILITY II,' PLASTICS BY A
Tli.üi-OP-FLIGHT II3T1I0D
E.H.Martin,J.Hirsch
Sol.State Comm. 1.279,783(1969)
The predominantly mobile carrier in mylar is negativo and
transports by hopping.Kobility-lifetine
produces are
in the range IO" 1 ! to 1O~ 1 0 cm2/V.
TO/
' T' C A M ' 1 .'•:•' ' 1"1'!jl.l,T:pi
• i ; ,
'
*l , ,
'.':•.o
,
i.;;o:.-:...
::c;'j.'..li t;
"
_ . " ' • • • • . •
>.it
.:;•:
• . . .
, '
.,'.
• - . • • •
•!;:.:..''• ^ -.:.., ; . ' : . - e : .
•:>.-.•
' • ••
;-i--
:'. t '•:•/"••'••••'..•••.., '^ . . . [ , . ' . . .
,.•••.•••„••.
,.~S
. '.' ' "
,'
"'"" .
SWa^Ri ^ ? '-ÍHE irjDlÜ.JiJS PLASH X~1"(AY PJIOGIIJU1.
T.::.ti3rt.in,K.R.Prestv/Jc!i.,l>.E. Johnson
A3 "a rcisuft oi'^-tbe'rapi'd' {jro-.Hh^f 'pulsed'po;rer t
attributable in part to rooearch performed by AViPJi,Sandia
Lab.
has developed,frubricated,and I D operating Hcrnoa II,
the largest flash. X-raj machine presently available. It has
I>roduoed a 150 kA beam oi" electrons of 12 l-.eV for 100 us.
Hermec I, a l/lO eoalo model,WÍÍB conctXTictod to porf.'orn necessary experimentation for the developuent of Eoitics II;it
wars later used as an operational electron beau facility .
The components of the Hermos machines a.re a lovi-inductance
I.arx Generator,a Bluralein transmission line,and a vacuum
tube in which the bean is forced by field emission and accelerated across the cathode-anoae region by taeans of applied voltage.All high voltage portions arc subnerced in
transforuer oil for in.oulation.The .Hermes II components are
housed in a steel cylinder 05 feet long and 22 feet in diameter containing about 1J0 COO gallons of_oil.?ho !,arx generator was doai^ncd fur 213 k'cV and 0.5 i:J,wit;i 1J6 caoacitcr
stages consisting of two (l/Z) P ,loo kV capacitors*
«
I
Biill.Araer.Phys.Soc. l8_,Ho.4,579(1973)
BK 8
EPR Dosjmetry of Bones front the Hiroshima
A-Bomb Site* s. MASCAREUIiASf-, Harvard Med. Conter
and HIT, A. HASEGAWA and K. TAKESHITA, Hiroshima U.
—Following the proposal of Pancpucci, Mascarenhao
and Torrile,^- bones from victims of the 1945
Hiroshima A-Bomb were found to present a residual
paramagnctism. By postirradiation and calibration
doses could bo calculated for different distanct-s
from hypoccntor. Results indicate the use of bono
ond teeth as dosimeters for nuclear accidents.
44253
(EUR-4452, pn 437-03) MEASUREMENT OF DEPTH
DOSE DISTRIBUTIONS DEPOSITED IK A PLl'.XIQLAS PHANTOM
IRRADIATED WITH A BEAM Of 10-, 15-, 20-, Of. 30-MeV MONOENEHGÜT1C ELECTRON'S. Mathieu, Jacques; IJlanc, Daniel;
Casanovas, Joseph (Tuulouse L'niv. (I-'rar.ce). Centre de Physique Atomique ei Nucleaiic); Dutreix, Andreu (Iiistitut Gustave
Roussy, Villo.'uif (Franco)); Wamboraie, Andre; Prignot, Michelc
(Louvaln Univ. (Belgium)). (I" French).
The lonizfilion produced in depth in a Plexiglns phantom Irradiated by a monocnerootle electron beam was measured liy means
of an ionizalinn chamber with dielectric liquid. The sensitive volume is a thin film of liquid (O.Si mm thick), the electrodes are
beryllium <lisen 0.5 mm thick and the chamber walls arr. of Plcxiglas. The In-depth yield was measured for 10, 15, 20, and 30 MeV
electrons; the results nre compared with those obtained •••••ith a
Baldwin chamber and with a ferrous sulphate dosimeter, (auth)
'
f
\,
t
5
12499
D1KLKGTHIC 11EHAVIOR OF SOME IKUAD1ATED
r
POLYMERS. Malveev, V. K.; Vaislierg, S. E.i Karpov, V. L. ;
(lust, of Physics and Choinif.lry, Moscow). Vysokomol. Soedin.,
Ser. A; 11: 2CGG-70(l:)e<; 19C9). (In Russian).
The effects of y radiation on electrons in vacuum and in air on
the dielectric behavior of polyethylene, polypropylene, polystyrene, and poly-a-niclhylslyivno were studied for a wide range of
doses (to 800 Mrad) und domi rates (to 7.3 x lo' rad/scc). Dependence of tg o on the dose of y radiation in air wan determined
for all the polymers. The increase of tg ó on irradiation in air is
related lo radiation oxidation. The latter has diflusion character
and the Increase of tg & Is determined not only by the dose, but
mainly with the time of contact with oxygen. For polycthylenes
a formula is found (for 200 to 1)00 rad/sec) that relates tj; ó to
the radiation dose In air, thickness, and crrstnlllnlty of tho sample. Tg 6 of polyethylene Irradiated In a vacuum increased on
storing in air, which caused migration of radicals from the crystalline phase, (auth)
16759
REVERSIBLE CHANGES IN DIELECTRIC C1IARAC^ERISTICS OF SOME POLYMERS FOLLOWING GAMMA IHRAIÍIATION. Matveev, V. K.; Vayasberg, S. Zh.; Karpov, V. L.
1'last. Massy; No. 6, 34-7(Jul 1071). (In Russian).
' Reversible changes in the dielectric loss induced by y radiation
were investigated for the following polymers: polylvinyl chloride)
(PVC), polytrifluorochloroethylenc (PTFCE). polytetrafluoroethylcne, the copolymer of tetrafluorocthylene with vinyliilene fluoride,
and polyethylene. The radiation effect was different for each polyH}er. The reversibility effect in PVC and PTFCE was associated
with an accumulation of volatile products of radiolysis. The effect
observed in the other polymers was connected with the formation
oj unstable peroxide compounds such as free radicals, (tr-auth)
<•
|
|
<•
,
j
j
t
THE CONDUCTIVITY CHARGE IN POLYETHYLENE DURING GJflMA
IRRADIATION
S.Mayturg,W.L.Lawrence
J.Appl .Phys.^^, 1006(1952)
I-ioasiu-oMents -.iith-a C060 r c i i u t i o n coirc-ca, at room -&OI:Ipoi\.turo and at liquid nitrogen toi:.por;..ture are ro.yorted.
•Jho l a t t e r give tvrenty-folâ decrease of the nor,..a]"
conductivity mid a 25-fold decrease of the radiation induced
te:.müra-fcure. An ionic nochemisn i s su-^-octcd/t.ii conduction.
í;!;inriCiu.rJ vcOtagen ave j'vErjucntly produced in im;u! piore
in a pulfieí nuoüeru- ivuUntio» .fi.«l<] .Thoy £i.ro due to positive
charges l e f t
in tho iiif/al,-;tor ai'ter a imolo;:r b l a s t hvz
o..-.-polled elooti-onu fro.,i t.ho m a t e r i a l . Recovery of tho
system can b-> cxnvcsaod in terms of a s>.infilo time con;;l;;.ni,
Lovi HiriiKCY io:r uoiJEAHD; .MIT i n S I O ^
D. "V. 1 icCuu^han, V. T. 1 iur \ :h,y
112SJ Tranci.iriujl.Sci. 2<':i-l£ ,lTo.6,249(1972)
LViticncc ''-.o been presoirted for for tho pr ceo rice of
uobilo ior.n in ion bombarded S i 0 o vhieh a.rc r.ocoibly
protons o r Ihi ions.A :..odol invol^Tni; nuutralination of
the incident ion beam at the surface, follovot'. bj" iir.purity
ion triinov.ort to the interface unáor the influence of
the field building uj> across tho SiOp film during; boi>b;:.r&u
has been constructed to explain the experimental dat;;«
BLMTH01I BOMBARDMENT CONDUCTIVITY Hi DIAMOND.I.II
K.O.McKay
Phys.Bev. Ji,l6O6(l948)i H>8l6(l95O)
It is observed that the ionized electrons and holes become
trapped at energy levels with sufficient lifetimes and
densities to establish an appreciable space charge.Measurements have been made of current decay due to space-charge
buildup which, are in agreement with, theory. A doable
pulsing method is developed which tends to neutralize the
space-charge effect and provides a novel method to study
rates of release of positive holes and elétrons from traps.
The voltage-current eq. is D= tl/~l ~ exp(~\i"-'.)_7' where
H / ò is the normalised yield, 6 the observed current passin
through crystal divided by bombarding current,ÔQ,the yield 6
for infinite applied crystal field, W=v/l the normalized
range, 1 crystal thickness,vi=FT the probable electron range,
v electron mobility,P applied field,T probable time an
electron would spend in semiinfinite crystal before being
trapped.This aosume3 step voltage ,homogeneous distribution'
of traps,space-charge effects negligible. Bombardment por-» I
formed through th:.n electrode connected to meter.
:;
IOK BEAM KLlX'TROGKAFJiY
!
R.J.UcClure
'
Rev.Sci.Instr,. 365X246(1966)
Properties of a variety of materials for collecting charge
patterns produced by ion beams in mass spectrometers
were investigated.Among the materials listed were mylar
bounded to a fiiass plate by epoxin ,ouoli mylar coated
with a transparent layer of aluminum on the reverse side
and others.Imiaages were made visible by a senr.itometric
method.
Túü j-HAijUKiJii::!1 OJ1 ELDCTÍiÜlí All D GAl-ilA-liAY iJCSE JJIUT'KIBUTIOI.'S 1IÍ V,Jil0lí3 ÍSKLA
U. I . LcLau^h] i n, I!. h • i iiia smarm
Inskii'^o l i u l i a t i o n bcui'oes f o r I n d u s t r i a l l-'rocoaf-jos,
Proceedings of i5:..npo3iurj,l-.u:;ich,lc}-2£ August J-S6S'ip»579
Koasiu-onoivb^ i.-ith radiochroi.iic cl^-e f i l n a uiid ^;t;Io a r o
r e p o r t e d . Soi.'ic r o c u l t ü a r e (;jvon f o r cm aluminu:.;-;h Ion—
aliu,iimi:.i-H;.loia í-vStem.Tra-.iuitioii and bacgBcattoriiiu e f f e c t s
arc soon. The i n t e r f a c e problen i s diwouused.
El^GTHOIT TlUirbl'OKT III Tillil líTSULATUTG F1U&
G.A.l-load
Phys.Rov. 12G,20i6(lS62)
Paper roporfS'-fuCita on Tc^-TajgO^-Au Dioaes of various teicknesccs at different temperatures Tf to detorcine tho ciu-rcit
flow uochanisra.This ics found to be f i e l d ionip.ation of trap
s t a t e s at low T and thermal ionization of these s t a t e s at
high T.High temperature current-voltage characteristics and
low temperature comparisons between between forward and r e verse characteristics agree with a bulk-limited hypothesis
and are in diasagreement with a barrier mechanism. A discontinuity in oxldo properties occurs at 50C°A thickness.
Jliçh. T meacureii-ents vrith an applied voltage smaller than the
difference 5ÍE±XJ2BEL in metal work functions yiold/j Ohnic
behavior with an activation energy of about 0.1 oY, consisted
with impurity conduction, but not with a barrier procee ss.
RADIATION INDUCED CONDUCTIVITY IN POLYMERS.
Meyer, R.A., Bouquet, F.L., Alger, R.S.
J. appl. Phys., 27, 1012(1956)
A/eojurements of conductivity of polyethylene and teflon under exposure to 2 MeVX-rays
arid lo Co°0 gamma radiation are reported. Currents are found to increase approximately
linearly with dose rate. Observations of \\v* current caused by the forward scaltering of
Comptcn electron? are reported. A sandwich system is used to eliminate this component.
43126
HKl.AXATION PIIF.NOMMNA AHSOCl.Vl'Kl) WITH
ÍMDIATION-INDUCKU TlíAl'1'lill CHARGE IN Al/), MOS
DKVICUS. MicheleUi, V. H.j Kolondra, V. (HCA I,;ibs.,
Princeton, N. J.). IEEE (Iml. Klec. Electron. Ung.K Trans.
Nucl. Sei.; NS-18: No. C, 131~7(Dec 1971).
From Annual conference on í u c k a r and spaco radiation effects;
Durham, N. II. (20 Jill 1971). Sto CONF-71070.9.
A semi-quantitative ni'.y'.fl baaetl on enhanced electron injection
due to radiation -induced trapped positive charge in AljO^—ÃIOS dcvicee 1B developed. This is found to explain the niuin features of
the charge relaxation phenomena observed following termination of
radiation with applied gate bias. This model provides for the exi.stenee of both nepitivu and positive riiarpo trapping sites in a c cordance with (lie results of oth"r workers. Under certain conditions, internal rerombinalion of trapped holes and electrciR was
found to play an important role in (he relaxation proceHft. However, in cases normally encountered in typical device operation,
the relaxation was found to bo nearly Iricnllcnl to the bias induced
pliift due to electron injection if one comparer? the phenomena for
the same ficlda at the Injecting contact. With positive gate bias,
this ÍH done by subtracting the shilt in flat-band volume introduced
by the radiation-induced trapped charge froni the applied ftate biafi.
Finally, the dependence of the net radiation-induced charge on fifite
bias and dose rate was found to be consistent with the picture devcloped to explain the relaxation effects. The radiation hardness of
AljOi-MOS devices is attributed at least in part to enhanced electron injection due to the high fields caused by the accumulation of
positive charge in the oxide near the injecting electrode. These
results chow tlvit radiation havdnesa increases rapidly with decreasing oxide thickness. Practical consideration involving device
stability Buguefltfi that a thickness in the range of 700 Â to 600 Â
Is optimum, (auth)
j
1
l-HOTOFOLAlilZATION OP AHTIlliAClSiE
F.C.S.liilanesjP.V.Uurphy
An.Aoad.Brasil.Ci. 3^., 15
Anthracene Dingle c r y s t a l s ' vecre p o l a r i z e d perpendicular
to cleavage plane by simultaneous action of e l e c t r i c
f i e l d and u . v . l i g h t . Decay c u r r e n t » , e f f e c t of anthracene
fluorescence r a d i a t i o n , and rríisxgKXíiitfcu?. p o l a r i s a t i o n
s a t u r a t i o n e f f e c t s vrero observed.
,
\
GAiaiÂ-ELHCTRlC CELL THEORY AM» BXP2HIÍ.3WT
G.H.Uiley,II.T.Sampson
.
isit.Conf. on Bnsrjetics^Univ .of ilodl-eaic-z,
IT.'.
The gamma c e l l d i r e c t l y c o n v e r t s gammaray energy i n t o e l e c t r i c a l euergy.Basic theory and preliminary experimental r e s u l t s from reacotr and cobalt-60
i r r a d i a t i o n are presented,Results for both typea of
radiations are in good agreement.
.
'
\
FT3SIOÍ!-FHAG1,:3ÍT TIÍAESPOTÍT EFFECTS A3 RI.X/.TITiD TO FIÍÍolCír-riZnÃ^a;'
iJLLCT^IO C;;LL TAmiJJ. KTICILIiCIL'S
Ci.II,;.:iley
Kucl.Sci.aig.
2±,322(1966)
MILEY
C.H.
DIRECT CONVERSION OF NUCLEAR RADIATION ENERGY. PRFPAIÍCD UNDER THE
DIRECTION OF THÍ: AMERICAN NUCLEAR SOCIETY FOR THE DIVISION OF
TECHNICAL INFOItKAYI ON UNITE» STATES ATOMIC UNERGY COMM] Í.SIOIJ.
AMERICAN NUCLEAR SOCIETY, 1970.
010 P. AMCMICAN NUCLEAR SOCIETY. MONOGRAPH SERICS ON UDCLEAK
SCIENCE ANO TECHNOLOGY
include::; «lotailcil. UÍ^CIVJÍJÍO'.; oi." Cyu^-toi; c u r r e n t
u:iu í_'í.u.:i.iri- t.lcclrí.c cclü b e h a v i o r .
\
The d i f f c r o a t i i ' . l fjpeoiril'.: of a i"i.;~;:'.:. Z-I-;ÍV VS- o!-,::er ±-^lv.:.C:
sojece !..:.'y "!>c \i:;cü "iiith t h e fcr.: i oolc::L:.\lc ii'u.li;.;j.o:i
dcbet:tor. The Ir.'ltey, a j'oj.cd COVL:.:/ÍO ler.vj. aii-coniun
;
7'5'-;
t i tana "to, ifi.xcí: a pulso outrut prcvo.r'^ior.;'.! to th.. do;;e.
Yo
^ ' C ' t t ^ ' G ['"{ C Í C Í Í P Í I I .
í i H ' 1 1 * w i-fj
''
i^O b O ' "
f
'\'GX'"'"«*::0r
'J. ' Í V ' '
'"'!) ' ^ •' "
iy vli'.co.l i n i'l-oiit oi' a co.vriijpotiair..; t . c t c c t o r . . c t , U\o
r a d i u t i c n ind;\cod tími^.e cvitTUt \dV.i a 0.6 ]'.YP f3c.;.;h E-:;-;^
;
±IÚTÍ: ir.aohiiio .arc iv-viorted. The rc-.r;; oi!. i. cu" tho r,._.:;.o:: i:j
dvr.tiiv.ic, yo i t CUR bo urjvd t o 'io:cr;nr<. tliio "bejiavAo:.1.
1
•EFFECTS OF SHUNT CAPACITANCE ON I'RAUSIEN'f UFFPJCTS
CAUSliD BY BLECIROU IRRADIATIOK OF A POLYflH'i'YLliiiE
TliREPHTHALA'i'E INSULATED RIBBOM V/IRB
V/.E.Miller, DfH. P h i l i p s
(NASA jLangley Ees.Center) March 1966(MSA-TM-D-352l)
An i n v e s t i g a t i o n of the effect of e x t e r n a l shunt c a pacitance upon the e l e c t r o n radioinduced voltage p u l s e s
from a 20.3 cm s t r i p of wire i n r a d i a t e d vãth 60 keV
e l e c t r o n s i s r e p o r t e d . Average max.pulse height varied
i n v e r s e l y with t o t a l capacitance,While a change in load
r e s i s t a n c e caused negligeable v a r i a t i o n in pulse
height«After t h e discharge,Lichtenberg e l e c t r o n d i s charge f i g u r e s are found in the p . t e i n s u l a t i o n »
< \
'
J.r } i:itchell,Jú.G.:üolTurc
Couf .Health I-hyi3.kcetinc»l&s Vegas,June 1972
Describeo a f,"cM.:na ãosiwetcr 'bc.saà on hecitinc the
i r r a d i a t e d dioleotrio i n a ter..peraturo ^
'
\
í
! C " C""1
} ' ' ^ ^ ' : ? - . ' . C " ('.':..'. '>. T i : : ! • . " • T . V ? . C " (.'" ';"?'}'*<'.(•'
'
- v - "
;
- - -
; :
-:.:-••••
Journal - I n s t i t u t e of JBlectrical Engineers of Japan
vol. 90 no.6 p. 206- (1970)
.•
-
•-
* - ••*•
- • - •
••
t
' - " - —
V
•
o
'
—
*~ • -
.
^- ' • • * '
•* • - * '
•*
- v
' • • • ' -
of t.ho uidc cJinino oi" poli'incrs,while CIOM diüc3"ta'f£;os
c.ravoo a tLcrnal Droa]:d.ovai accot.voanyi.t13 nonoir.'.re c e n o r a t i o n . .
1
DIELECTRIC BHHAVIOlt OF GEA1H B0U1IMR1BS BY üLBCTHOlT-WiAl.1 i
SCAHÍIN0
A.J.Llotvtvala,H.R.lúarks
J.Appl.Phys. 44,1499(1973)
The olcctron-bêam-scanniiig technique allov/s the etud^' of
the dielectric properties of grain 'boundaries and interfaces
One side of the crystaDi is irradiated "by a scanning
electron beam through a ground reference collector grid.
The other side is covered ~by a metallic back-plate electrode
where signals are read off through an amplifier in the
form of a video signal.The advantage is that the area of
dielectric evaluation can be of beam-spot siae.Physically,
the measurement depends on the charging of each point of
the (front) scanned surface by secondary emission to a
constant and well-known potential with reference to the
ground-reference collector grid.A typical measurement consists of tvro phasessa)establisbiaent of working potential
across specimen and b)iricasureraent .First phase is accomplished by applying voltage ramp to backing electrode -while
front face is being scanned by beam.Second phase nakee use
of the definition of the dielectric measurement to be performed.As the v&eo signal is just the net charge as a
.
function of position deposited on specimen between succosivoi
scans,conductivity phenomena would be displayed because
cond. is time-dependentj permittivity as a function of position phenomena is displayed because charge per unit area
deposited on specimen is different' for areas of different
permittivity for a given unit voltage between scans. Kocults
are reported for KG1 crystals and BaTiO3 ceramics.
THEORETICAL A>: ALYaTi, OF OP^U'I'KWAL GifA-ÍAOTl^íI3^'ICÍi ÜP
vianormwr C?WIW
n
R e s e a r c h T r i n n r l e I n n t i t v t o , Jhirh.v.i. J', Oc (l(j(>4
L
NASA CR-56316)
* J"*
.Hent
Two major aspects of tho y>ro"lilo;i: ;>,re considered;
(1) Charge ctoraee in the 6*HÍE<;ÍJ:5;K cp.paoitor riicOcctrJo
(2) Spontaneous discli: v^s renultins fi*om electron irradiation.
1
>.;,/
^^
{
^JCf,,,,..,?1.,T.,:,.r.,^,,..
•r.•.•:;,rT; r rrjA;.,•/;•:; V I L M S
' '
'""
'"'
"'
' •
)
-
1
•••>••
••-
L.!'.',.;.'ontni t)i
IJurlifinij J í . ü «jOuk.fi Un.'i v " : i ' f : i t y , D J Í J .
Ph 4 ]j«.*?})'• -ji ,'••
i STUDY OK TH:; EI.,K0Ti?OK IT(3AT)1ATJ.O]Í ÍCTECTS ON CAPACITOR.R o s e a r c h 5?ri.i:a T r i a n g l e
Ç
L. K • ilo n t o:i. t}x
Meaaurcment on e l e c t r o n i r r a d i a t i o n e f f e c t » on a c a p a c i t o r
s t r u c t u r e are ropo7't'-.'cl,K3ectrons were i n t h e 2ow anercy
range(up to [}0 keV) .Llectron t r a p p i n g i n iho d i e l e c t r i c
and t h e docny of -the trapped charge a f t e r ceasing of the
i r r a d i a t i o n have t>oon observed, Decay curve.", a r e conHistovfc
with a n o - r c t r a p p i n g r o l e a s o model which nainnnes uniform
t r a p d e n s i t y with r e a p e c t t o enci-cy meaaurefi from tho conduction 'band.A aatur«iti.on e f f e c t f o r trapping; i s obnerved
which gives a maximum t r a p d e n s i t y find a maximum value of
the i n t e r n a l e l e c t r i c f i e l d , llearsurementfl with beta
i r r a d i a t i o n have a l s o been performed.ana* In t h i s cace spontaneous discharge car. be induced.Breakdown i s believed t o
be initiated fcyxiiie primarily at defects in the dielectric
film; i t does not usually liberate the total amount of
trapped charge.
i
i
STUDY ON THE KLECTHO1I I37UDIATI0H EFFECTS Off CÁPACITOSTYPB MICROMETEOE1D DETECTORS
L.K.fêonteith
l
( R e s . T r i a n g l e Inst.Durham,IT.C.)
Oct.1965.Contract . '
HAS 1-3S92. .
Electron irradiation of capacitor struetóres consisting
of polyethylene terephthalate films with aluminum electrodes results in a trapped charge distribution in tho
d i e l e c t r i c . BEEay Charge decay curves i s consisting with
a model assuming uniform density of traps with respect
to energy measured from conduction band. Ass.tgggttw«
A saturation effect for trapping i s noted. 146 pm irsmi
beta irradiation produces spontaneous discharge with
exponential pulse shape.TixKxas±siczB£xi>iiexfcriiEk8team
EEEissxisxlaix Breakdomi i n i t i a t e d by internal space charge
field primarily occurs at defects in the film and
in most cases doea not liberate a l l the trapped charge.
/**/
we:-, ?ÜLY,,T.:YI.I;Í!K
T;/U.P:;TIIALATL
L.K .lion t ' i t h
J.Appl .P!iys. 2 7 ; 2633(1966)
pnrií
Elcotvon D rradi £.t:l on of cu.pt.f:j t o r - t y p o nystc^.'ia rc-.wl t a i n
a n e g a t i v e oblige riiotrl'ki'i.iori in thu tM o l e o t r i o p.'-ovidf:d tiis
^-''
t h e d i e l o y t r i o . Mc-üfin^crnaivi a .V'.-i-i.' iKvfiM-vJ! wi/lh ;... 5i On ...p,.. r , f; ; n,-,__.
t i n g tin<IQ o f Í X I O - ^ / Í / G I Í / ' - i n i i u - 10 t o ?." V:oV J/.M,^.-,, LxU-.i-m,?,
Gtivvft','
J
-'i
<"'•' C E ' U r c c
:;j"i.Ci'
-1*>" -.".:! : ' i t i o r i
h<r.i
'umsri
ò i . J Í ; O : ) V . Í - '.'t-.d
•;;?•':
r o l a t o r " t o chíiy-^tj íh.f.í-'/ i n tV,o d-j f:loui - i o , A fJi;:.p?{- :',o(ic7.j
ii.3iiig uni.f011.1 oliai'.^c d:' ütr-i.1n.ition <vj '-l;i -'i t h e i r r r . V : :.tf i vi-lv.^o,
^ivíi^
;J. c h a r l e i 'io-rr.vxiy of ;0,;cut 10 •> '••!VO'.;-(.IK-/CI.Í-'.
7cr
a 14 koV Ijftaia, -fc}i« f i o l d u e ^ r t h » olco'.-.-'oclo of Inoi'-Umo'? j u
an üi):iroc5:i!íi!-.f; v:-.lu'j of í-ilíW/crf. i t ;
pi
2
A cl.e1,;-:.i] eel vaode.1 oT .vpí-.ct—chi-x^c- eifc-ct^ I'te-altinj
from trt'.ppinfj of ther^f.liKed irrc-.clí;-..tion c l e c t r o n r i?i
i n s u l u t i n v T.;-.1;C i'.i:-.lí- i t- prtsc:rl.fcil. Analytic s o l u t i an;;
for tiie p a r t i c u l a r c;-..se of polyt'tliylene ttrep'i'-.hMlr-.'tt li.'-.v
have beer, obt:iirjed # '.i'hen the tr:-.;'pi:i-; s i t c v «re u n i i n r mely (liPtribiiutd in energy btlov; ího eüc-r;jy ].tvc-3 v^cro
clihr^e •tri-.nspoi-fc occurs?, the rtitc of charge tuiiiJui» f-.inl of
char^ç. rc-loaf-'t- titpeirls priiii.?-.ri ly on ;-. r:-.'tioyi oi tho
mi-.tcr-if.l rGli-i"f-.bion t i n t constant i;o a rc-3 (. i'.sc- r a l e of
electrons frov tr:-.p.<?. A^rtement if for t h t ciiist considered where thif? r a t i o 5:K of ti'iife con.vtur.te i s of the
order of u n i t y . When the r a t i o i s iiosll, hov/evc-r, very
l i t t l e external external current and charge i s observed
f--l)d, ,trapping,pa•••araetc-rs are not conveniently studied
i
7'^/
I
EFFECT OF LOW TEMPERATURE ON THE LEAKAGE OF CHARGE FROM IRRADIATED
METHYL METHACRYLATE BLOCKS.
Moore, C . B . , Vonnegut, B.
J . Polymer Sci., 33, 191 (1958)
U is found that charge storage of electron irradiated blocks con be prolonged by several
orders of magnitude, if the blocks are cooled with dry ice before irradiation and then
maintained of this temperature.
*-j jj2.
S.!. i.. J;
l;:coDoütc c; o. o :"!.;:••:• p t i v o iz ',-:.'i.vGivfc o.'.' Í : Í , Í : 3 Í - : i CÜ Í ? J L .
to
'bod
;'.. 1;'..-..'-v'—l.í.;,lc
' . j á , , : i . . l f j • ..'.'-(.:
C.iM'or.'i
'/O!:'
[•.iV.lo.^u.1,
it;
;.•. £ • • • : . - . i . i \ i ' j i v " : .ir;:.
iu
o : r L ; ' O r o i . .'bi.c:
l j . v . . ü ; . i t i o ! ' : i'í/j.'
. . C i . v :•.•'•. < . . t > ' " . ü t r .
n . r j J"T.:V
l'ri.:-:..ic;;j
: j , . ; a i l ; i »C' ..;_.:•.:.••;;—•;. .• J \ \ : Y:'.í: c v l .'.!••-
Í.:Í.;>.'.LU
5 r._;.':
: : . l _.::;.] zi}í
.r..
o : ; c j . í : ' ; - l . r í i : . !•.••, : : , _ : a r t
CJ.V;. :.;•••;•?. I
;.".\:
. i . <• .:.:;;;• ei..
j.';:o
electrons alHoir observation of the tino-í-tiEolvcú t r a n s i t ion pi'oncaa.V'ho;.- f.'.ho'.r t h - t .'rraco-chcav.o jvjj-tiivbod currents,
Í.S oi \Vijeü to i.-iCL-ourrciiitri ,;:TQ buli: .limited.
,
í
|
I
Wíi I'iilJORY OF '.ti.PUlíITY 0OY::Ai(m
Advun.in 1'hyc. Kl, 107(1961)
T '
S 1-T A
O''"1 001TDUCTI01I AJÍD VALB1ICB UA3ID
N.F.i.ott
C35 (1970)
p r sugeests thtit osacnticl fcaturca of band theorj'
may "bo a p p l i e d , t o ai.iorphoua c o l i d o , s u b j o c t t o t:ro n o d i f i t i
a) Por ciiíiordcred structurcfi, the ~bc.no. cap it; replaced by
a "poeudoG'ap" or r.iinii?.iir.i in the density of electronic ctatcn.
b)l31ectron statoc in tho pseudo^ap --s-V be stronr:ly localised,
so they cannot contribute to the conxmctivity except
thr.ouch processes like thermal excitation» In t h i s sense
the pseudo^ap behaves in the sane way &D a true band gap
to e l e c t r i c a l conduction.
\
IffiTUCTOKS ÇCR hK.SUiiETu SXiCSURK Wa~£ HAÍüo i;r WsJ il.i'M'Z.
\
10*3 to 10^ K/scc
2.V.Lu]"Jiacliov, G.L'.Radakova, P.S .SaniojD-.ov
] in.jJocinotrj- in Agriculture,Industi^; ,Biologj',end Lodieinft.
Syi.-,posiur:i,Vienna ,17-21 April 1S7?-. IA'^V, Vionwa (l';73),r"!>^
Describeü ioniaation ciiai.ibsrs r.nd vacuui;) Co::.pton dOvCcto^a.
Tliesese MGa[nr.ia"elc..:ents oyeruto botveen 10^ to 10 c h/coc at
tcir.poratiLrec up to 400°C. 3-':a;,;j..lee of applications in j^.:.:..a~
euittiíiü isotope i ' a c i l i t i o s &sd reactor:; are ^iven. ;:o avoid
tr.c effect of ulou ísecendar;, electro::.1; i.iovir.Q in t)io field
cet up between the electrodes due to posaiblo xotcr.tial
differences (c,.;rl;:ct poter.tir.l) ths ci-.ifctor aim collector
electrodes \rerc- separated DJ; a. quarts tube of 0«3 --i-; thicl'.r.e.';;;»
•1'iiuo i t ia p.oq uito clear v.'het; er the òovico ovc.v.tüü as a
puro vacuum detector»
A/
7ÍV
/
ciu;o..j.'ij i..: a ;
Í->L I .:::.V.'V...A-;.J LUCIVÍ
Th•':)• TàiO JÍ3,UfiiXG1IC0 ,ICci'iOt:.!J , U:)XV . O f
1970
DniY.J.icrofilli.if; Cròer lio. 70-23,3-0
This Mudy was concerned with the generation of electrical currents iu'a solid dielectric, Lucite, upon healing it after exposure
to x- or gamma radiation. These current:! an- generated without
the application of an external electric field. Insight Into the nature
of the poiRntl.il gradient n.:,|>onsible for charge carrier movement
was obtained by observing the currents gene rated under various
heating and irradiation arniniicments. Heating was carried out b'jth
with and without a net temperature gradient in a direction normal
to the electrode surfaces. Maniples
were irradiated both isolroplcally and dlrectionally with ejCo gamma rays and directionally
with 2f>0 k\'p x rays. Different sample thicknesses and temperature gradients were employed along with externally applied electric
fields to obtain some Information on the magnitude of Uie potential
gradients. Samples
were irradiated directional!)' wilh thin filters
(ICO nig/cm2) on the entrance and/jr exit sides. This irradiation
configuration resulted in trapped space charges in the samples.
The effects of these trapped space charges on the magnitude and
the polarity of the thermally induced currents v.-crc studied. For
samples heated In the presenuc of a net temperature gradient, It
was concluded thai the potential gradient responsible for charge
movement Is thcrmovoltaic in nature. The direction of the currents
is such that the colder electrode is always poslti.'o. This Indicates
that the sign of the mobilo charge carrier during heating an irradiated sample Is positive. For tampleb healed in the absence of a
net temperature gradient, the direction of the potential gradient in
determined by the direction of the gamma rays through the sample.
Upon heating, the exit side of the sample always becomes posiiivc.
The magnitude of this potential gradient appears to increase as the
proton energy increases. Results obtained using thin lead filters
during directional irradiation of samples suggested that production
of trapped internal space charges, associated with regioDS of under
or overdose, can also serve as sources of electric fields in the
sample for the movement of thermally released trapped charge
carriers. Using filters of different atomic numbers, the variation
of the magnitude of the underdose, for c0Co radiation, at the filter/
Lucile interface, was measured. These results agreed with those
of others who obtained them by ionization measurements. A
limited investigation of the consequences of applying an external
electric field during heating of an irradiated sample in a net tem- i
peraturo gradient yielded results suggesting that Ohm's Law was 1
followed for the doses and field strengths employed (up to 120
kilorads and 800 volts/cm.). (Diss. Abstr. Int., B)
:
•
:
,
•i';:^;{;:;j.L7 CÍ^FKÍÂTED CUJÍÍ^I.TS JBI.ECTRI.CAI
Tüi'JMií'Si\S} 1UCIT13
P.l! .i-.iu'i>3^v ,P.L\Koockor
Kc,diction' Koccaroh /ijÇ,l(
Thin clicks; oi" ooi:ii:!0.fo:ia.'.l P]U:A,cj.i'tor Jiavin;-; IJCCJÍI osposod to
£-;.'.W!.iii:r;i,vB,ci2:hibit clcclr.i cal currents,in t.iia itbconoo of
an txternull?, a l l i e d f i e l d uhcn c,)tlio cc-.i.-r-loc: aro h'..;..tod
with the ir.aiivlcn:-.noo of ft temi-orature ;jri,c.U.-.r.t Letwocu iho
electrodes or b) when they are Leutcd without a tcr,T.cr;.ture
difforer.co and the irrc.úlation war; directional with v not
cor.ironcnt normal to the electrode «urfaoo:-.,vith hích-o\ioi\-.
photono (X-ra;.ü up to ?$Q 3:V cave only t:..all effect:;)• for
caoe a) tho iclroctioíi of charge movoucut corr.sj-.cr.ds to the
movement of pouitivc charjo to the coldor e.lc;ctro(U!,fci' 1\)_
to positivo cliur^-e d:.s;-lacci.'.cnt tc.rard the c:d.t dido of the
car.:})lo. Cv.vrc.jt i>rof:üeH Kridb i t tuo pealx. A':onj tlio faotorc
ir.vosti^at'jd ;;ere : Ci;<iri;c as a fimction oi dose. After
an i n i t i a l ir.oroace sai.uriition ia .reached around
•jy-lC^xa.à.
- Charge an a function of heating rato.Valu.es arc ar.pro:d-.
mately constant, a l i g h t decrease being noted for very lovr •
heating rates. -Charge as a function of storage time: ])ecay
curves seem to f i t an expression with two exponentialc.
Charge as a function of sample thickness»Values otrongly
increase for very thin (l mm) oawplee. I t ocems that thero
are two components, one constant and the other increasing
with decreasing cample thickness.
.
52906
THERMOELECTRIC CURKENTS IN y-IRHAIHATED
LUCITE. Murphy, P. II.; Hocckrr, V. K. (Univ. of Kansas,
Lawrence). J. Appl. Phys.,- 42: No. 10, 400J-6(Scp 1971).
Thermoelectric currents were observed in thin lucitc disks
after exposure to V radiation. If an elpelrie potential difference
is also impressed upon the sample during the heating cycle, the
currents are enh.inced or depressed depending on the magnitude
and polarity of the applied voltage. The measured charge is a
linear function of the applied electric field strenf^h, and the field
strength necessary to completely suppress the currents appears
to bo more* closely related to the radiation dose than to the temperature gradient in the sample during heating, (auth)
DIESÍCS!RRADIATI0N
EFFECTS AND £NERGY
CONVE
R S I O N S I N SOLID
Murphy, P . V .
Rio de jano!ro National CommiSsion on Nuclear Energy. Laboratory of Dosimetry, 1 9 6 1 .
32 p . (Research report for the year Apr. 1 , I960 - Apr. 1 , 1961, unpublished).
,, Gemma ray polarization of insulators. Gamma ray induced electrical polarization of
,-nwbton it dsicribed and a theory proposed. I I . Effect of persislonl polarization on
various scmt.llotion materials. Tho radiation detection sensilivily for polarized
,cir.tiNation crystals is investigated. Anthracene shows a two-fold increase in efficiency
.flcr polaruat.çn ,n c,5 kV/cm field. I I I . Photovoltaic effect in electron irradiated
inwlofors. Reg.ons of space charge in insulators resulting from high energy electron
t^bordmont were released by ultraviolet light. Tho charge released from fused silica
.amp es was a very small fraction of the initial space charge. The photoconductivity of
Iirodialed samples was studied.
*
A *7 A
*• ^
. rOLARIZATION OF DIELECTRICS DY NUCLEAR RADIATION. I I . GAMMA RAY
i iMOUCED POLARIZATION.
Murphy, p - v - ' G r o s s < B ?io do Janeiro, National Commission of Nuclear Energy. Laboratory of Dosimetiy, 1962.
In Resoorch report for the year July 1961 -Juno 1962. (Tobe published: J . o;->p I J'hys. 1963)
li is shown how Compron scattering in dielectrics loads to space charge formation. The
Wlk distribution of polarization is discussed for various experimental conditions.
Veasuremenls were corried out on carnouba wax. Charge values were oLiainsd by
liiomial release. To obtain the spatial charge- distribution a sectioning method was used:
Alter irradiation the dielectric was cut into several sections which v/ere healed separately,
d.'icliorge currents during hooting woro measured. Core was tal.-en to ovoid any temperature
gradient «cross lhe sample; therefore results were not affected by any thermoelectric
effuct. The Influence of different absorbers placed between the source and the dielectric
win investigated. It was found thot olreody o very thin obsorber greatly reduced the
released charge. Measurements without absorber indicated that space charge density v/as
particularly high in the lop layer of the dielectric. It was concludad from these obsarvolions ihcit lhe effect is strongly depending on how for the incoming rodiotion flux is in
equilibrium with its secondory Compton electrons.
r
3
f'iij yon .A'J.'IÍ.:Í ::.'.:>
Hi 2
::>IÍ5C:VÜÍC!!Í OF CAIÍ-.V^-ÜA WAX 'Í&ÜC-.IÜTÒ
lv.~:or, Annual i.iduoist Solid S t a t e Conference, I C t h .
K-i:i:i:.ti C i t y , V.i.'.:::., O c t . 1^62.
iie^olf-riKvitioii of vux olc:ct;/ota ic; r.^í-.uuvcá 'by t-:e i.cf.od
of thori.uil KCtivution. •i.ba p o l u r i K a t i o n i:i S:;cr..-u t o contain
.
a r i . d i o - s o n s i t i v o con^oiicnt \rhich i " da^'broyod b;. '<•- t o 3 1HÍ 7/Ó
and v. coíiütant cor,roncnt ".;j;ici: i c not ^LTocico. D;-.- iv.-iiatj.ti!:.
HadiooloatrútD \.*uro forneú fror. v a r i o u s d i o l o c t : ^ c: v-.ciii'.j
\
THE FORMATION AND DISCHARGE OF CARNAÚBA WAX ELECTRETS I N NUCLEAR
RADIATION FiELDS.
Murphy, P.V.
írPhs.Chen.Solids 24,329(1963)
/ -, .
\
1' i
The denaity of unraired electron c-pins for elcctreta -.rci
d.etori.'.inod "b;, paranaa'net-ic resonance before and after
exposure to uasoive ganuaa raciiation. Kie irradiation
caucod a larco reduction both in. polarisation and in densi
ty of unpaired tsyins. Subsequently carnaviba vsz. carar,leo
vrerc polarized by simultaneous action of penetraiinc
radiation and electric field.
\
• •
•
" • • •
• • • •
-
•
GÀMUA KAY DOSIliETRY BY RECOIL' ELffCTRttV Ci^RRE-VTS XV SCUD
..urpy
?n Encyclopedia oP X Rays and Oaimaa Snyn. G.R.Clai.'!-. 4<3.
lu;invio:id Publishing Co. iiev; Yor>. l-i63, p . 304.
v
THE EFFECT OF PENETRATING RADIATION ON THE PRODUCTION OF PERSISTENT
INTERNAL POLARIZATION IN ELECTRET FORMING MATERIALS.
Murphy, P., Costa Ribuiro, S., Milanez, !•"., de Morces, R.j.
J . chern. Phys., 38, 2400 (1963)
Samples of teflon and carnnuba wax wore polarized by the simultaneous action of penetrating radiation and application of on electric field. Isothermal depolarization curves
end thermal depolarization curvos were observed; this method allowed to calculate octivation energies for lhe depolarization process in teflon, giving on average value of
0.93 eV. It is believed that the persistent hcterochargs in carnaúba wax and certain
polymers is caused by the orientation of dipolar units composed of a posilive molecular
ion and a partially solvatcd electron.
\
I
J
•
Lf"l L
i
POLARIZATION OF DIELECTRICS BY NUCLEAR RADIATION. I P.ELEASE OF SPACE
CHARGE IN ELECTRON IRRADIATED DIELECTRICS.
Murphy, P., Costa Ribairo, S,
J . appl. Phys., 34, 2061 (1963)
Irradiation of solid dielectrics with high energy electrons produces a region of negativo
space charge which may persist for a long time. Experiments are reported in which various
dielectrics (fused silica, pyrex, reflon, carnaúba wax) were irradiated with S.-90 beta rays.
Following irradiation the samples were stored in short-circuit for a few hours and then
heated or illuminated by ultra-violet light from a high pressure mercury vapor lamp. Thus
thermal and photoelectric charge roloass were achieved and the capacity of lhe various
dielectrics for charge storage was determined. Charge storage v/as found highest in
olectret forming materials and in materials with a high density of deep "traps". The
highest storage pholo-relcase efficiency v/as obtained for fused silica at low bela ray
doses (approximately 40$),
POLARIZATION OF DIELECTRICS BY KUCLEAR RADIATION.II.CAL1ÍA-RAY
INDUCED POLARIZATION
J.appl.Phye. 25., 171U964)
2fee P.V.líurphy, B,Gross
The electrical polarization m£ produced in solid dielectrics
i7ê
by gamma ray bombardment p's treated as a space charge polarization resulting from the production and absorption of
Compton electrons. Por a gamma ray beam in equilibrium vri.th
secondary electrons,the calculated net space charge is negative
in sign and decreases -with distance in proportion to gamma ray
attenuation.The fipace charge distribution is studied experimentally by cutting away sections of irradiated, carnaúba wx
wax and measuring the charge released on heating for each
section.The relationship of thermally released charge to saaple
polarization and the effect of a temperature gradient are «^ÇH«*1;Í/
'
HIGH LEVEL PASSIVE RADIATION MOMlTOKiTHE SOLID COMPTON
RECOIL ELECTRON DETECTOR
• P.Murphy
AD 675501(1968)
4376
(AI) 710007) DKVKU1PMKNT OF A PASSIVK SKLPI1EAD1NG l'KHSONNKL UtSlMKTlilt. Final Kt:|ort, November
19Cb-May li>70. Murphy, Pinttun V. (Thermo KJcctron Corp.,
\VaWi;im', MiiRR.). Jul li>7U. Contract X)AHC20-G9-C-0110.
JOOp. (TLi-4109-l3»-70). N'lIS.
A passive, yclf-ri'iiiiiiip tlofiitr.clor for hUrh level gamma ray
monitoring has Veen devi'lnpcd. The p&nunn ray detecting c l e ment UFCS eiif.Tfíclic Coiiiptüii i'nd photoelcetron scattering in a
dit'leelrlc-i-li'clrodo matrlv t>' piMicrMe tho charge necessary
{or doiC veati-ool. Tho tW*U:rti>is clement Ins l>rui designed to
provide u nnifoivn response for pliotona of 0.ÜS lo 2 McV energy
and to cliaruc an Inverse-reading riber voltmi'ior full scale for
total dosou in tlio ran^u of 200 to (100 U. F.vatuuU'd, Invvrtverending filh-i1 vcHmpl'M's of Muttnhlc riinfjo have been isbrienfed
ond assembled vith dciuelinj.; Í Icnuíntü to glvr prototypr? dosime t e r s . All protoiypfi uults wen. ívou of batturien or chfirv.Grfc,
could bo rend ujpcaterily whilr In a rudlatlon field, and showed
good accuracy nnd rejiciitibJllty. (null)) (USCiUUfl)
,
/
IVth International Congrcao on Radiation Research
Evian,29 JUJIG-4 July,1970* Abstracts, p. 1535paper 594.
PASSIVE, 32L?-REAT)I1IO HOOIKSTElt USÜ1G RRCOIL ELECTH0H
SCATTBRIÍÍG
PRESTOU V,"""HDKF7Tír
'
i
Tliormo E l e c t r o n C o r p o r a t i o n , K a l t h a a , HasüachueettB, C215-Í,
Ü.3.A.
Tho dovolopment of & new t y p e o f h i g h l o v o l (10-500 it) c a n on ray doDlmetor for personnel or area r.onitorlng i s deccrlbod. The rfifld-out technique io olrri|nr to that in current
UBaco I however, tho detecting decent derives an electrical rend-out charce froa tho radie.ti.itr» field f ami th-ju oHDlr.citea the noed for a separate chai-girc unit. Charge io
cc-norftted by recoil electron scattering in tm electrodo-dieloctrie matrix.
The dotectins eltment io a cylinder of heavy nctal, covered
with a foil of lieht octal, cr.CEipaulytcd in an ineulatirg
plaaiit}, ar.d the aoííombly (a-.proT.iKatcly 1" dieaeter by 2"
long) enclosed by a thin n,ctai nhell, 1'he heavy uetal cylinder acquirea a negative charge by virtue of ft difference
in the incident and eaorgent electron flux» The charge io
proportional both to the forward scattered component of th<?
Cotnpton and photoelcctron flux in the pl&otic insulator,
oná to tho photon attenuation in tho heavy total cylinder»
Tho otfoct on ct.ftr^o neattorirs of detector elzo, confi,^urntion, and cntorinlo io dlacuored. The evolution of a f'nol
deolgn, in vlev of ovnoitivity and oncrgy reoronoo requirocento, io described.
An evacuated, inveroo-rcodinc fibor voltretor with «tended
linear range h&a been developed to read detoctor churpe, 1'he
required vocuua quulity io not c r i t i c a l [ presouron ca high
ionizati
oo 50
50 produeo
produeo negligible
negligible ionization
loakiiee, while 1 i.a
unaccoptable
An overunaccoptable in
in secondary
secondary «nibeicn
«nibeicn ennma
ennma detectors*
detectors* An
hd
oil insulation rcaiotanee of 1 0 1 ' ohm has boen achieved
Uf. }
/Of
readily, and io adequate for general usage j ccopar&ble de-i
tectors have core atrin^ent requircnento,
I
Typical doaimetcra have an output of 0,3 to O.6 V/P., axe í
energy independent ± t5f" fros SO to t200 keV ar.d ão not I
saturate at,high dose rates. Connared to the ion chamber, j
there are potential advantages in simplicity, reliability *•
and cost»
I
PHGÜJO-STIMULATBD RADIATION EOS-IHETEE
j
K.KiyaDhita,n.ll.lIeiiisoh
Solid-Stcite Ulectronics 9,,6l5(l966)
Fhoto-s-fciraulivted trtnaients in sivi^le crysiials of ZnS
are used for u.v. and X-ray dosinetry.
\
METHOD Or PREPARATION OF ELECTRET5.
Myazdrikov, O . A .
USSR Patent 120 273 (1957)
Dielectric is polarized by fields up to 30 kV/cm ond simultaneously subjected to action
of beta, gamma, or X-rays. The absorption of such radiation leads to the formation of
olectron-hole pseudodipols, whose moments are oriented preferentially in the direction
of the applied field. This results in the production of a polarization in the dielectric.
tyf
3
/ • / '
••
j RADIATION_ EFFECTS IN SILICOH
-~~
~~Ji-A-.Wal3èr---É;s;Wickner (Gen.Dynamics,San Diego.Cai
•
J
Gen.Atomics Division)
'a j " '
Qiarterly Progress Report July l~Sept.3O,196B
NASA-CR-80 133;GACD-6249?QPR-7.
*
The electrical conductivity of high purity n-type Si
was investigated by microwave technique after irradiatic bJ>
by 30 MSV electrons at room temperature.Electron "
spin
resonance
tisstkn&vsizxssx
s t u d i e s were made on hi ah
spin r
e s c
tehtó
r e s i s t i v i t y material t o e s t a b l i s h coordination teiívâ
between microwave resonance and c a r r i e r l i f e time "" studies.
i
1 (1Í-67-25G7Í!) VJ'.VJJ-.'nOYi F/PFKCiS 017 SILICON;Quarterly
1
i lj:o.;rü»;;3 import) October l~!üecrj:;ib'."?r
yi,lljòó.
' H^b'Ji1, J.7>. jíloriyGjH. (Gonercil Dyn-icics Corp.,ürn X'.Lcí;,c>
ü a l i í . General Aiouic J)iv.).Jyn.lü,19 ( j7' L ' o i V ' s r " c ' t l l i A S '/"
2S9, ;iOi).(líAriA.-0K.-85Gir);GAC3~624S). 01'üTl.
.V.oí;n;;ie>rl; :nd qv!ic;?:eort Klac-s\ical fír-.nduo-fcivity
i n )i.i.i'ii.«pi.ir:i-l;y n-typc s i l i c o n was ."tudieó by ilia
microwave ieclmiqiiG c-fler ii-racliation by ">0 lioV
elGclro;ic at- roo:;! tcmporature, '.Í.'3IÜ e3.eci.ron ílnzv/arcoírtrolleci so thí.rfc tho iutroduo'i;:.í;n oi' %hc. r(;Oo:./oiHH.™
tiuA oo:iit«r wíiiã íicítcjcioã. P r e - i r r a â i u t l o n lii'etici.-: i
meanurin.íoritG were made urjin^ a íl&eii Y.-TÍ:^ Jüachine* i
end ilj.e r e s u l t s &re f.no\\rn. ' 'J-ba £;aiupl&a end i.!icrov;i-.vc ;
e.pparatus were ír.oved to .an electron lines:,? accelura^oi 1
(lÃnr-.o) v/here extra precautions v/ore taken so t h a t
J,
ng l i n a c tuning the sample v/as not irj-Kciiatedv/ith
i^b-snei'gy e l e c t r o n s . The p r e - i r r a d i a t i o n lifa'OiEie
of the higb-rosiotivity Si sanplos was analysed using Shcckley
Koad theory. The dc contaictivity transient laeasu-rcnents on
Si samples of carrier concentration of «JLCH-^/CEW are also
briefly discussed.
. t.
|
i
|
j
j
i
i
I
j
j
i
j
1
j
\
j
1
j
1
i
1
'•
!
52254
STUDIES ON BOMBARDMENT-KNHANCED CONDUCTIVITY. I. INCREASE IN THE ELECTRICAL CONDUCTIVITY
OF MoOj AND VjOs FOLLOWING ION BOMBARDMENT. Naguib,
H. M.j Kelly, R. (McMaster Univ., Hamilton, Ont.). J. Phys.
Chem. Solids; 33; No. 9, 1751-9(S»p 1972).
Measurements of the sheet conductivity of ion-bombarded MoO3
and V2O5 show that there is a conductivity increase of many orders
of magnitude for c'oses o£ 2 x lo 1 «to 2 * 10 1! ions/cm* of 40-keV
Kr, the final bulk conductivities being 20 to 200 SI'1 cm"' for M0O3
and 20 to 600 i!~' cm"1 for V2O5, Reflection electron diffraction indicates major structural changes in the irradiated materials. Thus
the initially crystalline MoOj and VjO6 first amorphize (1 x 1 0 "
and 2 x 10'4 ions/cm2, respectively) but subsequently crystallize
to lower oxides, the appearance of the latter being an indication
of bombardment-Induced oxygen loss. The lower oxides, MoOi
and VJOJ, are known from other work to be metallic at room ternperaturc, and there Is thus no difficulty in attributing the increase
In conductivity to their formation. The reason for bombardracntInduced oxygon loss with M0O3 and V;OS is only partly understood.
The fact that the altered layors have thicknesses of roughly 1150 ±
250 A suggests, however, that neither normal sputtering nor
bombardmant-enhanccd vaporization is by itself the cause.
Rather, a long-range effect, i.e., one that correlates with the
Ion mean range or which involves diffusion, must be partieipatIng. The conductivity increases found are regarded as having
several important applications. 1'or example, they Imply a severe
limitation on the use of MoO3 or V2OS in a radiation environment
though at the same time they suggest a new approach in developing
b£ "7
'
'
GAM.5À íiAY DOSIIIETRY UBIITG COWI'TOIJ SCATOSUED ELECTRONS
J).l-l.Mycroj Morton E.Wacks
T r a n s a c t i o n s ANS 1 3 _ , U o . l , 4 3 4 ( l 9 7 0 )
Univ.Arinona
Measurements wore made with a 1.27 cm thick PB absorber
sandwiched between 2 PWJiA d i s k s of 1.27 cm t h i c k n e s s .
A c a l c u l a t i o n using an equation pV-*
fy
g i v e s excelont agreement i n the 0 to 50 R/iain range,
c u r r e n t s b e i n g of the o r d e r of up t o 10 pA.
LICHTHiiBKHO FIGUEUS A".'D K-'PiiiCi'IVU Ui.üCiViO}; i ^ O j j
Y.llakai
I s o t o p e s and Radiation (Japan) 3,76(1060)
lioafiureuento of e l e c t r o n beau cilery- vcrsiirj LiGhter/h-irf i g u r e depth a r o r c n o r t o d f o r irruc;'i.--itod '•!•' '• P - P D I ^ - - "
a t -1«;6°C cud -JIPG~ .
' "'" """*' ' ' "
I
r
U^'-aCj 1 uTJCHOl'Uuy OP 33ORCSI] ICA'JJJ GL..SS
\iir.<: Ü;Ú-.L\ RAY?
Y.lTí.ü:ai
J.Chen:.Soe. J a p . 6o,l!}3.';(lS'6l>)
48520
IONIZATION OF DIKLIÍCTIUC LIQUIDS BY GAMMARAY. Nakayama, Tat.oyoshi; Kawano, Minimi (Kigoya Univ.,
Japan). Oyo Dutsuri; 40: No. 4, 35B-Cl(Apr 1971). (In Japanese).
Sonic characteristics of ionization phenomena in dielectric liquids irradiated by y rays from cuCo were studied, lonization current was measured with a parallel plaK' ionizalUm chamber. In
the chamber, not only the field Intensity but also tlie electrode
spacing could be changed Independently. Applying Jaffi'H theory
on columnar recombination to the obtained characteristic curve of
ionization, the saturated value of iunization current was estimated.
The collection efficiencies for Ions In several kii:ds of dielectric
liquids were studied as a function of field Intensity. The average
energy per ion pair, W-value, for several kinds of dielectric liquids
was estimated from the value of lhe saturation current from which
the influence of secondary electrons emitted from the chamber wall
was excluded. Using tlie W-value of carbon disulfido measured by
Mohler and Taylor as the relative standard, the following W-values
for dielectric liquids were obtained: n-hexane 25 cV; cyclohcxaitc
22 oV; IsoocUuio 22 e\'i toluene 93 eV; carbon tetrachlorldc 54 eV;
tetrachloroethylenc 50 eV. (nuth) (Japan)
» -/ —
IONIZATION OF SOLID DIELECTRICS BY X-RAYS (INVESTIGATION OF CERESIN)
Nasledow, D . , Scharavvsky, P.
Ann. Phys. (Leipzig) 3, 03 (1929)
Increase of conduction ond absoiption is observed. After irradiation is discontinued, the
current decreases siowly as in dielectric absorption.
i
INDUCÍ3D VOLTAGE STUDIES IN A COBALT-60 GA1JÍA IRRADIA0?OR
L.W.lTelms
ViL-TR-64-149,Tech.Rep.,Air Force Weapons Lab-,Kirtland /^B,
New Mexico,February 1965
'/^ff
20390 (FÜK-214) IKWJCSD-VOLTAGE STÜMSS I)J A COSAM»--6 G
GAMMA IRRADIA TOR. L.V7. Neliiin (General Dynnnics/Fort Worth,
Tex.) Feb. 1965. Contract AF29(6Ol)-6213. 34 p . (WIr-TR-64149).
CFST1.
An i n v e s t i g a t i o n i n t o the b a s i c mechanism cf gammar a d i a t i o n induced c u r r a n t and v o l t a g e i n olectr.xcal syetoros
has been s t a r t e d by urging the» HARF 1500-ourJ.e '''•'Co
radiation, ntourco.
S t e a d y - s t a t e moaGuromenls of e l e c t r i c
p o t e n t i a l s im'l.ucGd in a s p e c i a l l y c o n s t r u c t e d hollow
c y l i n d r i c a l c a p a c i t o r KH a function of gamma field,
d i r e c t i o n , gamma f i e l d Btrongth, and apparatus temperature
are d e a o r i b s d .
From theso d a t a , i t i s concluded t h a t the
Compton process ia tho dominant mechanism involved.
A
theory io developed e x p l a i n i n g in d e t a i l how e l e c t r o n s from
Compton c o l l i s i o n migiit produce c u r r e n t s i n a simple
i n s u l a t o r - c o n d u c t o r system.
The v a l i d i t y of the developed
equations v/us tested, by experimentally i n v e s t i g a t i n g tho
dependence of induced c u r r e n t upon gamma f i e l d i n t e n s i t y
and upon t h i c k n e s s of d i e l e c t r i c i n t e r p o s e d between thn
e l e c t r o d e Í,Ü.Í the r i i u i u t i o ; : i:-ov>i-c&. I t \\\:i T(A\nu tj-.ui;
•irJ.t::.in the nt-.i-ro-.: ranjo of y f i e l l into i .u:it;. a v r . i l a b i c ,
tl:c induecú currcr.t clcpoi'.'i.cd l i n e u r l y 0:1 1'ijlv. iutor.r;.'.
aa p r c r i c t o d "by the Kn . .
STUDY 0? VOLTAGES I1IÜUCBD VIITIt 1300-CURIB COBALT - 6 0
IR1ÍADIATI03J iuID A 3-l.Iíf 3JUCLKAR HIViCTOR
L.U.lTelms
AFWUTR~6'j-22,Tech.Rep.Air Force Weapons l.ab.Kirtland APB
,llew ""- ' - "
•""•"
REVERSIBLE RADIATION ELECTRICAL EFFECTS IN DIELECTRICS.
Nssierov, V . M . , Nesmelova, E.S., Olshonskaja, N . J . , ^Aikhoilova# T . H . ,
Poihakova, G . I .
Fiz. Iverdogo Tela, 4, 3010 (1962)
Measurements ore reported on tho behavior of the loss factor of various dielectrics under
irradiation from a Co^O source. During irradiation a gradual increase of losses is observed;
eventually a steady slate is reached. After cessation of irradiation losses decrecse end
ofter a certain period the original condition is re-established.
w:'FECT
OF GAMMA RADIATION OK THE DIELECTRIC PROPERTIES OF
SEVERAL CABLK MATERIALS.
V.M. Tlesterov, E . S . Kesmelova, K . I . Olshanskaya, and T.G.
Mikhailova (Tomsk S t a t e U n i v . , Siberian SSR), Iav.Vysshikh
Uchebn. Zavedenii, F i z . , No. 1, 147-52 (1954) ( i n Russian)
The e f f e c t of gamma r a d i a t i o n on the d i e l e c t r i c p r o p e r t i e s
of n a t u r a l and s y n t h e t i c rubber a r e i n v e s t i g a t e d . The dependence of the d i e l e c t r i c l o s s tangent, the d i e l e c t r i c constant,
and the e l e c t r i o conductivity of these m a t e r i a l s on ii<radiation
time i s p l o t t e d , ( t r - a u t h )
/óu?
CÜAliGlüG OJ? Vilffiü./iJ, ÜíQ FI1L3 Ir,'
An e l e c t r o n ou .wont flov in 'ihcrMul UiO^ ;f'iL.-o o:-- aciaâ to
vutor ](,•;.«, to r.c-.jativo charco builòup i n o::iC>.<.. i'h:i.:, ir; eu
to ih;i foruation oi' vat or r e l a t e d oculoiv; Í'.-D.#.T.Í:I uctiiiü
tiü e l e c t r o n tX^Ti.^hfiU 0:10 o:;: tborjo oyntox-Li it; ;.ur-..oü,-itomic Iiyiirc/ioi: i s :,'oi'i.:ecl \ri::;.c!i O.iffií^.e £t-.:;iv ami ov:.;:r!;v.ull;v
a otablo negativo cliar,:;e i:; lüí"tC:;iuu utc3:-oí'i' r~v... rjrii.ctr;
Arcro perfosisod to ciotcn/iiuc 31 íitia'1 i!v.r;t:-j b;viio:> o.+: l-iio
ciiíiri;oj us v o l l ;:.r; to iL'jtuj'i.ino i;:itcr -.üfi'\':;ion J-.iuoW.cn.
'i'::C t,j.i(3];ncGrj et:?ter caoh ctuL-ofi' '..-;ÜJ j:;O£-curotí. ciecti-j.call
í'ro ... i/alüO C-V.chc.rcotoriyfcics.
OLD;; CÜHVIÍS 11: CA»;:IJ,; SLQJIJJIÍ
K .11. j.ioholn, J . '.íoodc
H i J
x o %
1 , 7 3 ( ; 4( )
Ko-or:inGntr,ll;.- doton:ii!iu;i. curves for Í. vr.rict.v of Cdfj
ci?.-oí.ilo are p^^oeutod.A t-iut-voy of av;.ilablo k:?:J.ytici
j.-cthoás for intc;i-j,»retc-,t:ion of e",i.,ori;..eiatal rorroj.ts i s
üiven. Data aro evaluated by I'icano of different r.otiiocí
An cdoqiiute cxporiuontul procodttre ,'.;ivc^ conci.atcnt
Vi'Juoo of trap depth and capturo CXOL-Ü acsction for at
lourjt 6 Cifforcnt sctfj of trajxj.
T).K.i;i chol s, V. A..J»van Lint
SxsKEaBtxxnB IKZ'LI Transactions on l.acloar Jcicncs :';.>^13.S1J.9(^S'
Transient effects caused by f.-f.mma rays, tsloctrcns.neutrons
and heavy particles? in irradiated SSTLS. insulator:! of enor—
giv;ed Cíiuacitors aro discuusod. The "microsoopic" approach, of
the paper takes into account the fact that
the ior:i?ation
t
i s deposited along discrate particle pathscFor sufficiently \
low doses and dose rates trap over] f.pping- i s ESFJJ; ininimal '
and responsive from several paths i s additive.? *c avar^e
trap occupancy during carrier in;mbbiliaation,é.rifl thus lifetii.ic,
is mxxr.'ky.x 'deter.iiined \>y ionization density alonj; the trrij
and not by average ionizp-tion density throughout the sampio.
iú:r. At higher dose rates path over]aipins fjtartfi ;>.nd
tx?.nx?.£ carriers trapped a3ong a previou;-: pa,th mn;: ch-'-rigi!
trap occupancy and/or electron-ion recombination probability
for suboequsnt paths crossing the f i r s t cno.Mhf;n .tin-. óViti
law fa.i]fl. For the strongly ioniK/Linp heavy 0-articles
externally measured currents and ch,rr;.;o tr.-nfifor cro
than for fainma r;ys or cloctrono because of proi^ron
recombination of carriers alon;; the clonail/y iomi'.cd p
1
i
) RABT/iTIí'K--fJt.iwul.-.í-«O K'.T i n C s l CRYSTALS
0 . H ,Wj yi-.r.ovn, 0 , A .i.'Hnkovn
Piü.Tv':r-ío^o 'Pela 8., 3 7 5 ( 1 9 0 6 )
liííi.tf.jur.ürr-jvlH w i t h X-r.?.ys i n c i d e n t on nin<*lo cryti fc;<l s arc; r o povtvti f • lool'ToniOt,:'vi) f o v e e : ; u;"i t o i?UO i-V wore o1.):.v.;rvc'.1,
t h o cjf'j'i f;t >i,• • <•> a I h r e s h o ] d. of 30 kV.I.;?\i;.nui:i u s e d u n ^ r c y
v/i-.s 60 k'.:Vy.'". kV. 'PVio inf'lurries? of t h e p o s i t i o n c>f tl.'e i r - r s . diífior. "fickidn oi" t h o or-vai:.'] íind t i m e e f f o u t s w.-rvi i n v c í s t j ^
. TAxir>. Trim Sx.r.x.il.i::l.íatl fiur.r".-.!Cjo o f i n o i i i o n c o var; •Cound t o
beconii! i . / ? c a t i v o . J t n.!? oonoluífid t h a t t h e onosorvo<' e f f e c t
i s a-r.-.o,;intfMi with (\i.í'Tnai on oi" Htructur-;.] dftfectu av*ay
from the irradi»tc:(í cBction of the c r y s t a l .
,
Ü'.;"o;''o:.u:-'í.ij! •' .'.:.::;: :oto
??.!-..r..;::i-J.V;r..
}Ct:rl
C\\v
••:!•';:
Cli'i'.Vii.;!::
i :ÍTÍ•••/:'.•'1
i n
;
'I'.-v O ü " f - í l V ] : ' ; t 1 ' ' X T '
t'-'J t1?:; i r ^ t u i ' 3
^:-T.-O.0.lt
i:.- ;r:-;.?.:!.ol*ov ;• -:tí.ií:ir;il ? •-•] t o il:- O.iiy.vViO'.-. o:f '.he- k::..:..;.
1/c.i..:.:.:j';i-j e f f e c t of a C 3 i'i- t h i c : . C:\ i-.lütc 3 •- i i : vci. J;::. ,J.'.vGô .'ÍV.G o ; T o c t i .: A:x<: t o i'-i'i i'::l;r'.r-o c-f '-o1:.;. +o::
cloct:!.-o;i.o i.mi t r o i n j e c t i o n of ÜCCO 1 :' 1 ; 1 ^ O] cctro;:?; ror.c l.va•ti!: o 1.6 j.ii.i.Vho clu.a'je dii.vki'ifcution i n t h o :.:•.:.i')ca 5.o
iiri'o:!-:.-(.:'d • ut.^C'iij ouvrcüi, r c v o r o n l ü r^:-o cl>^cx-vua. Oiu^o.^c
i n .ort thnii 1 di.r.' . t i o n \rhoa t h e to::: c m t i i r c ,_T...Ucr:'t e;-.:-,::jo;
fro:.; I.\-:;:T.3 l o l t o r.oi^.-fil t o t h e "bci^:.
ATIOK :0?FJ3CTS-OK PLASTICS, ELAST0K333, LÜ3SICAi:íS, 2TG1., AKD
SCvS NATURAL ORGAtilC 1,'ATEHIALS. A L i t e r a t u r e Survey.
Anders Kystmera and í.íadeleine Selebnrg ( A k t i e b o l a g e t
Stockholm). Dec. 1 ? 6 3 . 4 2 p .
Atomonergi,
A b i b l i o g r a p h y of 154 r e f e r e n c e s i n a b s t r a c t e d form i s p r e sented which i s a r r a n g e d • i n t o two p a r t s c o v e r i n g r e s p e c t i v e l y
t h e p e r i o d s of 1$52 through 1957 and of 1955 through J.iarcb 1963.
ny
o
•t^Tiion FOR ?:íOiTJ;rj:i!^ .••:iJi';ov;rro CV^^T
ACTIVITY
P. >•). O1"1!'art
J.Anvl.Phyr..
2.2,1 SO/i (1 Q[31)
Short
VP.O:: RAPTC/-
r,\r:'v.\HV''.'.',in{\ mv|/.i £r ;>
RADIATION lüJJJCKÜ CO^.I/JCl'lVITy Al.;i) «Ai'.AGI'J C?1 TlIiJ KJ .KOWI
IIJSULATOR
S. Okabo, K. Tnmmor i , T.Tubato., íi.]fc.ka.-..ura
Ann.Iteport Rad.Conter Osaka i'reí"oc:lurc 7.,3J (lrX>C)
MuasHireiiientss of conáuc:tivity ;'.nd linduced cwrontv. arc r e p o r t e d , u s i n e a 2- l i n e a r a c c e l e r a t o r , iij'foctu of tei.'ijiaroti.Tc
changes and aftoi'-oiTiJctn aJ-e ob.'.'.co-vcd.A permanent i n creaisc oi" conductivity- \iaa found i'or i'orcterj to,
a coraisic nctoria] .
I
vi j
\
PULSIVE RADIATIOH-IKDUCED CURRENT IK ELECTRIC . ' '
INSULATORS.I.
S«Okabe,KtTüumorif T.Tabata, K»Kawabiita, S.Nakamura,
T'.Yoshida' .
" '"
"
"
——-•Annu-iiRepiRadiat-.Cen.ter "Osaka •^rfefect.8,55 (1967)
'"
.Radiation. induced, currents _(RIC).- in various- kinds
ef i n s u l a t o r s were measured a t the_beginning; of the
TrrsiSi'ktion "an'd~it"s pulse" "shape" was observed v/ith
an-e-eci-llosoeperRadiat-ioB-v/as pro-due eel by an 18 MeV - ' S"f>'/
JiiHEííK...eleotron. Lineac...y.ariations.,6f. the. RIC-puls<s
shape v/ith time and temperature shewee? almost t h e _
iame~features"ln~some"cases. Pulse" shape" depended "~~
on-the-a-irect-ien-ef the- c r y s t a l axis x-f • the"• sample—
MaijnsJ..jth.e._raâiati®n,..JP.uls.e. shape, is... discussed i n
terms ©f a t r a p and hole medel»
.
Í |
PULSES RADIATlCI,TJ-l;:njCi;D CÜKRyiíí Hi CKYSO-ALLliiB MID
FUSED QUARTS
S.Okábe,K.Ts-umori,T.Tabata
J.Appl.Phys,_40 ,2894(1969)
Kadiation Center of Osaka Prefectua-c .
Reports studios carried out with 5 iiicro-sec pulsos of
13 MeV electrons,current density of about 100 KA/CEI peak,
average a few inicroaups.3?he pulae shape of the induced
current varied rer.arkably wctJi tirae within a few ininutos
of irradiation and with the temperature of the sai.ipless.'i'iie
variation in shape shoved a dependence on crj stal orientation of the oaraple.The effect of tlie internal space
charge field vras founa to be neclicible.A qxtalitative
explanation is applied to p..rt of the results in terms
of an interaction "between excited carriers and traps.
_
40174
UHPENDENCE Ol' PUL.SÜD-RADIATION-INDUCED
CUlillEXT UPON' DIRECTION OF M'PI.IKl) ELKCTRIC 1'iri.U
IN CRYSTALLINE CjUAHTZ. Okiilw, SbiBerii; Tuirnori, Kunihiko;
Tabiil.'t, Tntsuo; K;iwnhut:i, Keiiwkc; Yoshiiin, Tusliio. Annu. Hep.
Radial. C c n t c Osnk/i Prelect.; 10: 31 -3(l.%0).
Pulse shapes of the radiation-Induced current in crystalline
quartz wore observed hy usin 8 the pulsed electrons from « linear
accelerator. The variation with lime of the pulsed-radiaiionindueerl current was found In Ije dependent on direction of thf applfnd electric iicld with respnet tu the crystal axes, and the dependence uri direction of tin.' incident 13-Mi.V electron beam was
not appreciable, (autli)
St>
6
i
4617
TRANSIENT PHENOMENA OBSERVE» WITH PULSED
RADIATION'S FHOM A LINEAR ELUCTHON ACCELERATOR.
Okiibe, Sliigsru; T»umori, Kunihiko; Tatata, Tatsiio; Kawabala,
Keisuke. Annu. Hep. lindiat. Center Osaka I'roiecil.; 11: 61-G
(1970).
Triinsient iilienomtinrt of physical interep! u.slnfi pulsed radfmions
from a linear eloctron accelerator an: f.tudffd includiiig (1) drift
of the piilsed-radiatíon-incliiced curj-enl in crystalline quartz with
iri'adiation time an;l its depeticlünce on an^lc Uctwcen th*- cr>-Btnl
axis and the applied electric field, (2) after-pulse phenomenon in
the ionination chamber filled with various kiiiti» of gas, occurring
with some dependence on radiation intensify and applied electric
field, and Cl) transient emission in ionuruion chamber*, probably
caused by charged pas molecules absorbed on the surfaces of
chamber material. The ihlrtl phenomenon is considered to have
a serious effect on the use of ionlzation chanibcrb. (auth)
/-/j *i
O 1/ I
455D2
EFFECT OF ELECTRIC FIE1J5 DIRECTION 024
PULSED 1IADIATION 1NDUCÜD CURRENT IN CRYSTALLINE
QUARTZ. Okabe, S.; Tsuinori, K,; TabalA, T.; Kawabata, K.j
Yoshida, T. (Hadiation Center of Us idea Prefecture, Sakai,
Japan). J. Appl. Pljys.; 42: No. 9, 3545-7(Aug 1971).
Ucpcndcnco upon sample orientation of the pulem! radintiontnduced eurrenl (RIO in crystalline quartz was Ktudlcd by UBinff
5-nsec. pulses of electrons with an energy of 13 WeV. The variation
with time of the RIC was found to depend on the direction of the
applied electric field wilh respect to the c axis of the crystal, but
not appreciably on the direction of the incident electron bearn. Dctailed dependence of the pulsed RIC on the angle 0 between the
applied electric field and the c axis was measured also for 0 from
0 to 30° at intervals of 15°, and the variation with time of the RIC
was found to be large for 0 < G0° and very small for 0 > 60'. The
dependence on 0 was confirmed by measuring the average RIC with
a picoammeter. (autli)
\
TIUWSiKHT BLISO'THOIT CUJüüSTT OBSiffiVKD I N GAS I01ÍIZATI01Í
CHAlZBBRS
S. Okab e, K. Tsumori, 0?. Tabata
Huol.Instr.Methods 104,109(1972)
Gas filled ionization ckarcbers, irradiated with pul.-ed
electrons or X-rays,nave been found to show a transient
electron current (TEC) after the applied voltage has been
cut off.Building up and decay of TEC,effects on TEC of
temperature,radiation intensity,nature and prosstire of
filling gas,and electrode material have "been investigated.
The TSC is believed to be caused by gas molecules and
ions adsorbed on the chamber walls and electrodes. One
component of T10C might affect the accuracy of current
measurements performed vith the voltage applied. Repeated
pulsed irradiation changes the current pulse shape.
/
/
FKK!{OET,KCTinC UEUAVTOH OP P.A1VI ATTOk' '.V.!:..-E;v:n TH"L';j,Y< 'iNK *
SIK.VATK A?JD !JOr:HRT,T,TC SAT.T UP TO HTOÍT DC;'; A HE
K. Okada. -T. A.Oony.nl o , J . M . R i v n r a
J . P h y s . C h e m . S o l i d s ( O i ? ) 2 8 , 6 8 9 (l.<)i-.7)
P u r p o s e o f t h e i n v e s t i g a t i o n was t o d&tor-mino w h e t h e r t h e
reported drastic decreases and disappearance of the
hysteresis loops and blurring of the peak in the
(Helootrie constant versus tnmperaturr: curvo were- due
to destruction of forroeloctrioity i t s e l f , or
to the progrer.sivfi masking of ferroelectric cihíivontovi
by presence of large accumulation of r?!dii.tion-:induoed
defects In a s t i l l ferroelectric environment. D't
was found that the ferroelectric characteristics are> well,
preserved up to dose.s of 10 MM? Mrfid, for the sulfate,
and xip to 2 I-'rad for the s a l t . In the l a t t e r ease the eff.
effect was due to the collapse of both Gurie points, r
co:r.iíjcii1ivi'iiv i,: :i:.r::;u:.ATJi:c:
S.Cka:::oío, J ,i'~uruta,]-'.Kirao.ka
Ann.Iíop.Rad.CDntor Osaka I'refocture ^^«(li-'Ga)
KÍ ,s;ii Go^° doses ir.ottify the "tho nolcculsir utructuro of
loJ.yothy.'lcme in ouch a wayy that Lhe inducoá carrcnt:; ;u»d
coiiciuc;tivit,y wi^ht decrease a f t e r pro-irrad.a"t.ion. ';');o
jiapor rotortü a sérios of i.r.v
41473
GAMMA-HAY INDUCED CONDUCTIVITY IN INSULATING POLYMIiHS. V. Okamolo, Shliilchli Furuta, Junlcljlroj Hiraoka, Eiichi. Annu. Hop. Radial. Conter Osaka Prefect.; 12: 7 8 80(1971).
Decay curves of polyethylene after Irradiation are decomposed
Into 4 exponential decay components. Decay time constants for
these components are independent of the60Co gamma dose rates.
Using Fowler's model, the dose-rate dependence of the Induced
current during irradiation doea not agree with the one estimated
using decay curves after irradiation. By the use of our model
It can be shown that the dependence of induced current or. doserate obtained from growth curves is in good agreement with the
one from decay curves at the dose-rate range of more than 5 x
102 R/h in this experiment, (auth)
Docay tirao constants at 26°C are 3-6rain,13min,41 i*in>
130 min. The last one has tho highest initial amplitude.
This time dependence affects measiireraents of raoaationinduced conductivity during irradiation ao a function of
dose rate»
RADIATION EFFECTS ON ELECTRONIC SY3TEÍS
H.L.Olesen (Missile and Space Divi si on, Oen. 151, Company!!
Plenum Press,New York 1°66
i
SUPKALINEAH CUKKENT-VOLTAÜE DEPENDENCE IK IRRADIATED
FUSED SILICA
D.Onnasch
Z.Naturforsch. 24a,851(1969)
The measured field-arid temperature dependence of
gamma-ray induced currents is explained by fielddependent electron capture cross section.Comparison
with a model gives a constant mobilitty between
8 and 300 °K..!iihe acoustoelectric effect is observed at high field strengths.
26306
THE v-HAY-INnUCED ELKCTHIC CONDUCTIVITY
OF FUSED SILICA AS DKPENWKNT ON VIEJJJ STJiKNGTII,
TEMPERATURE, AND IRRADIATION TIME. Otinnsch, I). (Univ.,
Kiel). Phys. Stains Solidi; 38: 570-Ü2U Apr 1970).
Tho y-ray-lnduced electric conductivity in fused silica is studied
theoretically and experimentally as a function of temperature,
electric field strength, sample thickness, and irradiation lime.
Synthetic glasses containing water show the highest induced conductivity. Caused by un increase of positive centers capturing
the excited electrons, the conductivity decreases ns r ° with lhe
irradiation Ume t, where a < 1 Is a con.staiit, depending on ternpcraturo. Within tho range from 8 to 300°K, Induced currents
nrc meosured with voltages up to 2500 V and dose rates between
10 and 200 Mrad/soc in synthetic samples 0.2 to 4 mm thick.
The gradual transition from constant conductivity at high temperatures and low field strengths I' to an increase of conductivity proportional to F or F 6 at low temperatures and high field
strengths is explained by the deformation of the Coulomb potential of 2 x 101! to 5 y JO14 cm"3 singly ionized, electron-capturing
centers under the action of the applied field. The comparison of
the theoretical dependence of the electron lifetime on field strength
and temperature with the measurements allows one to conclude
that the mobility is Independent of temperature. This Implies the
clastic scattering of the electrons at about 3 x 1 0 " cm"3 neutral
Impurities. Furthermore, the mean free path of the electrons for
loss of a phonon at 8°K is determined to bo 106 A. (auth)
26307
CURRENT SATURATION IN UtRADIATED SYNTHETIC FUSED SIMCA. Onnasch,D. (Univ., Kiel). Phys.
Status Solidi; 38: 593-7(1 Apr 1970).
The y-ray-induccd current In synthetic fused silica (containing
water) is saturated at field strengths g 1.4 x 10' V/cm caused by
two effects. Besides the schubweg saturation known from photoconductors with blocking contacts, the saturation of the drift veloclty of the •. .eetrons at the level of the velocity of sound is
demonstrated. In some samples, especially at lower temperatures, the effect is accompanied by instabilities of the induced
current explained by charge redistributions, (auth)
KSC0Í311IAT10U. OF IOifS
L.Ciisager
Phys.Rev. ^.,554(1930)
,
'Tho probability of geminate recombination i& computed
from the lavra of Brovni&n tiovouont. In the absence of
forcer other than Coulor/binan, t^o escape probability
equals the reciprocal of the Bolt:;::'.ann fr.otDi.', The results
include tho correlation between teiaportiture. rind pressure
coefficients of ioniz;.tion \rj lijht particles in ionisation
eli&nbers. The effect cf an external field is to increase
the fraction of escaping ions \rhich in the ir.cipcnt uto.^e
is proportional to the field intcsiisity ana independent of
tho initial distance,though dependent of the orientation
of ion pairo. The predicted increase is little :.:oro than
!)-• for every ICO V/ci.u A reasonable ai::ount of columnar
recombination helps to explain- the greater effects at
veak fields.
•
Sll
Ç/ /
*•*
5J~T
'
1
'•
i
RADIATION EFFKWS Oil mr,l
l?,F,Overinyertj).K»Niohol!s>V.A.J.van Lint
Quarterly rept» no. 1,-1 Juno-31
AD-626 474
(General Atomics, San Mego,California)
05 tleo-h-ic •v'eStudies on trunniont r e l a t i o n effects on car-àoixòr^
C-.'?"
are reported. Irradiation faoilitic-.-a used ino]uf?ed pulcoa'1
Trj ga reactor and Acool crator pulaed Fast Ar.oernV>ly,
Air trapped i>\sido smoDl molded-ca£;o capacitors might
have cau.f.ed some anomalous transient effoctrj. A
for proton i r r a d i a t i o n firas been outlined, líuinorxcal
estimates of neutron induced conductivity and charge
• transfer i n d i e l e c t r i c s have t>oeii improved. Uoutron and
proton i r r a d i a t i o n effects are difjciissed and a jaodel i s
• developed. Charge transfer due to r e c o i l protons i s aloo
discussed.
1
HAJXLATIOH Eyj'SCTS 111 UIELUaTUIC liATEPJALS
R.F.Overj.icyer
A'3-643643' Rep.Gen.Dynamics Co. s Goii.Atonies ü i v . .San
Calif. (1566
"Irradiation cxperinents to verify theories of transient
radiation effects in insulators are áiecueseà.Kigh-eneroy
«iloctroUjprotoiijand neutron irradiations of specially
/
Resigned Ilylcir capacitors are planned.Experiments dosignedi
to measure polariaation and secondary emission effects in *
thin-film capacitors and thin-film circuitry on sapphire
are described.Initial results of irradiation of Lucite
samples by electrons from a 3 l^eV flash >I-raj^ machine indicate internal diEciiarçe resulting fron; strong nonuniforia
electrical fields created in the material "by radiation
Ion-»ircplanted electrodes on i-jylar capacitors indicate bette:
carrier injection characteristics than foil contacts,but son»
polarisation effects attributable to the contact still retail
Lucite samples irraciiatod by electrons from 3 IleV flash X-ray
machine shoved strong internal discharges due to radiation generated strong non-unifor:.; internal fields.
tip.
J.Uhem.Phys. £2,2285(1970)
5Z1)
27272
CUnilKNTGK NT RATION IN HAHIUM TITANATK
UNIJEK THE INFLUENCE OK y IIIKADIATION. Panclwnkov,
G. M.; Plmhnlkov, V. M.; KaiiRiianskil, D. A.; Gla/unov, B. P.;
Avrorov, A. A. Izv. Akad, Nauk SSS11, Ser. Fiz.; 35: No. 9,
1900-2(pppl971). (In Husfian).
Gamma radiation produces on electric current in a polarized
BaTiO, crystal In such a manner that the induced emí ir. proportional to the radiation UWRI. Upon varying the temperature of the
experiment between 5 and 150°C, a maximum emf was observed
at 30 to 4u"C, a minimum at 90°C, with the curve passing through
null points at CO and l.'iO'C. A mechanism is proposed for this
effect. (K.S.W.)
VIA
»->«i /
D1ÍIFÍ1 OF CA1LKIBH3 A'/fBR
TiütOUOJIOUT A1.Í JiíSULATOH
A.ü.Panadakifj, P.IT.Keating
' i i j - o .
1(6,613(1965)
'I'ho theory of one-carrier laotioiij neglcctiii;- recorabination and diffusion, are obtained for the external
current, indiicod charco, and transit tine.
S?
t
A
—THEORY- .OF-TJIAHSXENT-S EACE-CHARGE-..BERTURBKD-C.URRENTS -
IN INSULATORS
• CPapadaKis
!^.Phys.Chem.Solids(GB) 28,641(1967)
àér refers to currents resulting from drift of
excess carriers.The latter are assumed to be produced
instantaneously in a narrow sheet close to one .
electrode.While blocking.contacts exclude secondary
currents, carrier capture at deep and shallow
trapping centers is considered. The space charge
field causes a broadenkng of the initially narrow
carrier sheet,even without diffusion. The current
pulse, as a function of time, depends on the ratio
of applied field to space cgarge field. Che theory
is compared with that of many and Rakavy.
\
ti)\ .
A PULSED ELECTRON BSAM APPARATUS FOR TH3 3T0DYOF
~CÃRRI3R"?~RÕ^d:UTll3iriN^^5ULST0?.3
A.C.Papadakis
Gonf.on Energy Bsams and Their Uses,York,England ,
23-30 September 1966. (ASO Conf.(56-305-4)
Describes an apparatus for study of luminescence and
carrier properties in high r e s i s t i v e CdS by Spear 1 s
method,v;.lth energies of 50 keV,vertical sensitivity
10 V/div, horizontal 0.5 nsec/div.
;
1
I THÀÍISilàJirT líIGii-EirtIHGY ItADIATIOIT-IlOTCliU PIíEE CARRIER
" A33SOK1 TIO!,' 111 SILIOO1!
J . Appl. thy o .JÍOJ 3416 (196(;)
HiüJioB Aircraft Co. ,l ; 'ullcrton,Calif.
The tiEic-depondont f r e e - c a r r i e r abeor])tion induced by puJsed
10 L.'eV electrons v:aa s t u d i e d . I n contrast to previous i n vcsti;>'itions, c a r r i e r s v.-ore Generated a t these energies
throughout the bulk of the irradiated material.Also the
free-carrier lifetime was appreciably greater than the
pulse duration.
CO;;DUCTIVIT7
unwoEu
BY SLUCTTÍON BOKMIIDICTT IW TUTII
ISSULATING FILMS
L.Penfsal:
Phy3.Rev.J2, ,472(1949)
KOLK OP 'ÍRÁPPIIÍG PROCUSSiiJS IN SOLID ÜTATE l
DOSlkETllY
1TY0-3409-8. - Progress Hop.,1969/1970.
(1'enncylvania State Univ.,University Park.l.'atorials
Hos.Dopt.)
A etudy of the us© of electrete for uv dosimetry ie
described.
26S20
(NYO-3-409-9) HOLE OF TRAPPING PROCESSES
IN SOLID STATE RADIATION DOSIMETRY. Progress Report, '
1970-1971. (Pennsylvania State Univ., university Park.
Materials Research Lab.). Feb 1971. Contract AT(30-l)3409. 3Gp. Dep. NT1S.
,
•—'Research on radiation dosimetry by polymer electret depolarization is described. Also, the characterization of non-luminescent
near-insulating materials by the measurement of thermally stimulated currents and thermally stimulated depolarization is discussed. Radiation dose measurements based on carrier trap
filling are considered. Equipment and results a r e discussed including the measurement of pyroelectric coefficients and the
characterization of lunar materials. (W.H.K.)
fyc
TSC study of (raps in clcctron-irradiaícíl Teflon and
,'•
*
•"
J. J'hys. D : Apr!- Phys., Vol. J, \'J12. .
-
Í
M M J'ERI.MAN nml S UNGIIR
Ctilli-ce mililaiic royal i!c Sai:it-Je;iii, S:iin(-Jcan, Quebec, Canada
MS received 20 Juno 197,1
Absli.'irt. "J"ls--Tni3.l[y slliiv.ilatid cuircnl> (i?c) have, been iiv.-asiusd f.-o;;i Tcilc-i ( : ; i : )
and polyctliylt-nc iiiaJi.iicJ iu vacuum v.iiii lo-.v.cnorf>- (6 !.-jV) c-'ccirons si - M-O'C.
TJic si>cclra from boi» nv.i'.cri^.Uarc \iitu.i!!y idi'iiiical, and rnniist of 5-.".en oCcil.ippitii
pc;i!.s. 1-acli mv.cri.il COIUÜHIS a! mo>t lhtiv Oiiicrca! traps in spile of the br-.'-.v nr'niivr
of peaks. AH of lhe t r . i p f c t r í y í s a i j i l o c . i p ; frcaiu-nci-.-s !i:-.ve leer, iUti:ti,v.'::ii for i-it;;
iind ;•. i;i!i'i'.-.'t of tlicsv. fo: )V>!>v.-.!i;.lcn:. 'I lie results st;;-: ost ti:.:t \',;;:c i r e Ji::'v.-.-e:it
sifUv^iral K'i.itioiH i;i s r.ii'.i-: i.i! I \ T llio s-i.i;o t>"i~c of i m p . :T.I! tlv\: i'l.Tireiv:^ i"; ;>.;.'.:;
|.O:ilic.r. n o ijiio U> kiiliiTV.'i liojiT-.'S of ir.' '!;'•;ci.ir n'-Clk'H. >.'c- r;:i'(S r.ro cV :.'.".•.•.'. !';o::i
cill.-'r mv.vii-.il ;'.!:ov.- 0 C". iV.vb-.is v.o:': !:.•:•; ih.v.wi a '.I'-v i-i^.-.'vr i f ; \ : . . - s ;:!• ••.-.•
0 'C in'iO v."(.'i..i;-i.i-ili.irvoil sp.-i'i:iiens. ' l i i ' , ;'->.i o'.hi-r refills sh.O'.v l!;-!1. !!.-.' 1' :.^.:e.-"j
sl.il'i!iiy of coi\nia-i-l'..iiiyd clcctretj niusl U- attrit'iilcil to io:i it.ippins r.iili,-,- i h ; n I
l
!
'
"I
\
8569
THERMOELASTIC DOSIMETRY OV BEI.ATIVISTIC
ELKCT?ON HKAMS. Perry, F. C. (Sandia Labs., Albuquerque,
N..Mcx.). Appl. PhyB. Lett.; 17: 408-11(1 Kov 1970).
•_,
A technique is described of obtaining directly the energy absorptlcnrprofilc of a solid healed by pulses of intense radiation. The
appropriate thernioelastle equations were eolved for two cascy of
particular interest, instantaneous deposition and energy absorbed
at a constant, rate. The dynamic response of aluminum and copper
to electrons of average energy 1.5 MeV was measured by means
of a laser interferometer, and the resulting energy profiles were
compared with profiles obtained using a thin-film dosimctry techniquc. The resulting quantitative agreement with the thermoelastic
theoi'y is discussed, (auth)
|
|
'
tpo f)
»* V
p
|
48915
INITIATION OF EXPIOS1VES.BY H!G(I-HN'!2KGY .
EUiCTHONS. ritiuiR, P. V. (Lockheed Palo' Alto He-search
Lab., Calif.). .). Cliem. Phys.; D3: 2906-13(1 Oct 1970). .
With very short and very intense pulgos of fast electrons eueh
Ail from a Ftbctron machine, many explosives can bo initiated •
at doses clearly insufficient for uniform heating to initiation
temperature. This provides an opportunity for further testing
of the hot-spot theory on initiation of explosives. In this study,
a stochastic modol in presented to describe the noininiform
spatial distribution of energy packets ariaing from absorption
of electrons or photonG. Computer calculations using an appropriate heat conduction equation determine what avcruge temperature (or dose) arid correspond»)!; hot-spot temperatures are '
required for Initiation. Critical donon calculated for )'bNs,
I'ETN, HDX, HMX, and nitroglycerine oro 37.R, 21.4. 38.5, 37.3,
and 21.0 cal/g, respectively. Exiicrlinontal doseo for dcxtrlnntcd .
PbNc, DtiNc, basic lead styphnatc, nud normal lead styphnate, are
estimated from limited experimental data si 11, -19, IS, and 10
cal/g, respectively. Factors responsible for differences' between
calculated and observed values ore indicated. The correct order •
of magnitude of the calculated results is considered as evidence
supporting the thermal mechanism in initiation of explosives by
high-energy radiations, (auth)
..
:^;a~Y .•s:.;:-3ici:r;:-:
;.':D
~:.^m:; : :cY
'
5*3 /
.
OF CCI-.VÍO;: AIPJ
j
-<ot
1
J.LrPi i ; :. v ;
iicp.i:;"'3-U-!3-1252,
J u l y l^f.G
Oi-leu']. :••/['•'} OP.'.' v.i'c- c;-cx'ifcd ov.t u.virj.-; '•(-.:• c n t l v ' ü c v c o o p e d
•Lri-.ne:a:i. £'i-ion íu:".ct,:i o. s ;-,ná c;-. r o í nil c ' i i c i d ^ r ^ - t : ' :m o i
c o i - . t t c r i n . - ; t i T c j ^ s . T.n L-MI.1 u. s'>. s i s , l . - o v t v c r , l : ; . s : d OJI
•tlif- i J i J u i - r t u t ;-..vf-i.'i;->-l.ÍL>n -Li'-l i-l-iC h : i c . : l c t v ; e o f "J-Í-Í
nc-l c u r r c i i i .\oros.v w:c t i c : ; i.ro:V.
boun;: ; -.ry i 1 ; • . ! ! V ;-.
i t r e q u i r e ; : f o r •:• o.tc-oVJr f.--t-!-..vitivit" u-.lerT.iin;-.'.ion. ,
TH35 ALPHA-CELL I)IKi;OT-COKV3i?.3ICj: CJUXAiVfCa
( W n n l Koportj
A.TÓ.Pluramer^.V.J.íÍKitfaBssspíiSjJiniKiyx
Gallagher, li.G.
Matthews s J.K.Anno
Final R e p o r t , 3 a t t e l l © i'emorial
Inst.Col.Ohio,Nov.1QÓ4
KA3A-C3-54256
.
Tlie cencratoj.- used direct conversior: of aj'pha particle
energy i n t o e l e c t r i c i t y . C h a r g e "build-up i s observed over a
period of 50 to 100 h r . V o l t a g e "buldup i s l i m i t e d "by
microdischarging.'Eoo e f f e c t of a EESHXX c o n t r o l e l e c t r i c
g r i d on secondary e l e c t r o n omission i s investigated.Methods
for converting t h e high v o l t a g e expected from improved
design i n t o lov/er v o l t a t e a r e also discu3&ed.
THE MOSIMETBR - A NEW 11ISTRUME1IT FOR KEÁSURIHG RADIATION DOSE
•H.J.PochjA.G.Holmee-Siedle
\
RCA Engineer 16,No.3, 56(1970)
\
Some MOS structiu-os can t e used a s sensors of accumulated.
r a d i a t i o n dose. The Mosimoter measures dose l e v e l s froia a
f r a c t i o n of a r a d t o 106 r a & . I o n i z a t i o n of t h e gate i n s u l a t i n g
m a t e r i a l r e s u l t s i n a trapped charge of p o s i t i v e i o n s , t h e
negative charge b e i n g dissipated, by leakage of t h e more mobile
e l e c t r o n s . The trapped charge causes a s h i f t i n t h e d r a i n
c u r r e n t versus gate voltage«Curves r e p r e s e n t i n g d a t a taken
before and after irradiation usually maintain a near parallel
relationship.
r
O7>3
-5"33<y
9645
INTKKPnETATlON OF RESOLVKD GLOW CURVE
SHAPES IN urci'UI-lOO) 1'KOM 100 TO 500'K. Podgorsak,
E. B,i Moran, P . R.; Camoron, J. R. (Univ. of Wisconsin, Madison), pp 1-8 of Proceeding of the Third International Conference on Luminescence Dosimetry. /Mejdabl, V, (ed.). Risoo,
Denmark; Danish Atomic (energy Commission (1071).
From third inicrnatioiuil conference on luminescence dosimctryi Jiieoo, DcmnaiU (11 (Jot l'J71). Sec HIKO-2-)0(Pt.l); CONF711026.
Each filow peak of LIKITLll-lOO) in tlic temperature rani;o from
10l>° to DOCK displays a fchiipP, peaking temperature deimndonci on
hoaLlnK rate, iiiul lack oi [JÍ!ÍI1<ÍIIÍÍ temperature dependence upon total
light output which arc In detail nn predicted by the most simple
thermally activated klntlles In the flrot order H.tndall—Wilklns
limit. However, the glow curve breadth ia anomaloutíly large at
low temperatures and anomalously small at hip.li temperatures.
While physically reasonable, ,'iUhoufjh Improtable, mechanisms
might explain the larger breadths, there neeins to exist no physically I'easonable direct mechanismfi to explain the narrower
breadths. An Indirect explanation is proposed in which the activation energy is itself slightly temperature depc-ndent. I[ow this effect
explains the observed results is discussed and other implications
are considered, (auth)
I51.E0THICA1. COKOTCTOTTY DIIiUCET) IK MgO 3 Í H2LATIVI3TIC
EL3JCTROÍÍ BOViD A1UJÍ/, KIÍT
J.II.Po]D.ard,D.L.Eowler,I.Í.A.Pomorantz
J.Phys.Cheia.Solids £6,1325(1965)
Effecta are o'bserved on thin sampiles/i so that the electrons
traverse the targets with small energy l o s s e s . Tho current
immediately after irradiation as a function of doae builds up
to a temperature-dependent saturation value. Conductivity
i s heilieved to be due to c a r r i e r s thermally emwi ttod from
a single trapping l e v e l . Conductivity glow curves gives
indication of several trap levels between O.96 and 1.69 V. j
«5"3.i~'
i SOLI» STATE INVESTIGATIONS UTILIZING
j ELECTROIT-BOMBAEMKKT. PHENOMENA
M.A.Pomerantz
.
(Bartol Res.Foundations Sv/arthraore,Pa.)Oct.29,1965
C o n t r a c t A T ( 3 0 - 1 ) - 2 7 3 0 , 77 p .
Measurements on electron beam effects on conductivity
in diamond,RbBr,liaBr) as well as effects on éesorption
of atoms from surfaces and connected e f f e c t s .
.
,
t
O N THE EFFECTS OF QUARTZ CRYSTALS IRRADIATION BY MEANS OF ELECTRONS.
Porre ca, F,
.
I Nuovo Cimento, 23, 859 (1962)
J Quartz crystals of thickness greater than the electron range hove been bombareel with
monoenergetic electrons beiween 0.5 and 2 MeV. The relation beiween depth of
coloration produced by irradiation and lhe electron range is determined. The intensity
of coloration is found to be constant over the electron range. Absorption spectra have
been measured.
<
537
15933
(WIIAN-KA -IB) 1N-VKSSE1. DHTKCTOK CAULKS:
SIGNALS OH NO1SR? J'orlur, N. S.; Hoiiink, K. C-, .lackson,
C. N. J r . (WADCO Corp., Hfdilainl, Wash.). 10 Sup ]«?U.
Cuiitract ATM!i-l)-iíl70. lup. (CONF-700SHM-.J). Dcp. NT1K.
From Conference on Power lteaclor Systems and Coniponenl»,
Willianisbun;, V.i.
Sovenil co.ixi.nl cnWes are investigated under the conditions
of reactor coros: high gamma (luxes and temperatures near
12U0DI-\ The exflel mechanisms of cabin failure by breakdown
pulse remain unlcnown, but it is concluded that the type! of d i oloctric is dufinltuly a factor. IK.W.K.)
0 ? GAMMA RADIATION ON THii DIELECTRIC'
0? QUARTZ
A
:
. . .
.T
I z v . Vyfsnh.Ucheb. Znred. Fi. 7,. Ho. h , 110(1966)
E f f o c t s concerning dielr-ciri.o l o s s , capacit^.rjcc,
c o n â u c t i n c o , nnxl p o l a r i z;i.t:ion have heon invco t i
Both s i n g l e cr,y.str?.lp and and fused specimen:; of
q n n r t z v.'pre nrnpl oyncl .LleamirrTnontn wore: taker: "between
40 tTod 10^ eyc'i.of; per s e c , a t room t e n p n m t u r e , an d
v.nder prosuure of 10"5 nra lt^ ( t o p r e v e n t efi'eet.s
due t o ,'dr ion:i.:-'.:\t:i o n ) . '^Co-^air.^as "/ere u:-ed.
In crystals, effects due to polivriaaticn by trapped elcctronri
were observed wliicli vrere aboent in i'uaod apecimenc.
«
° /
í
1
otru.ci.urccj thj prudes-nee of Ci.ar^o in íno o-iide JI:'.C pro—
found, effects en the V-I characteristics.rhc theoretical
V--I cui'vea for c::v.o:ieivliall-." aif'tributeu. o::ii.i.c c^.arjc
have "been -crived and it hits, been a'io~.::z t:;at e:::.::.i;-atio;i
of both I-Y and C-V curves \.ci-Kits to diGtiii^ui-::5: betuceti charge i;i tht oxido fro::-, interface charge."Jsinj thic
Jact evidence hac> bee;: presented G O sho'.r that both in—
triiisic interface fixed charge and the charge associated
with, fast surfa.ee states tire located within about 20 A 0
of the Si—S1O2 interface.Finally it has been sho'.r.: that
one can can actually extract o::ide charge distributions
fro:.; photoir.jcaticn cata and a preliuinarj- charjc
distribution obtained from a charged,steam-grown SiOg film'
has "been presented.
\
r.
L
EVALUATIOU OF SELF-POTOESD DET3CT0RS IN EBR-H
C.C.Prioo^.R.Karvinon
Trans. Amer.Nuol. So c. 15_, No. 1,366 (1972)
I.
X-RAY INDUCED ELECTRICAL POLARIZATION I N GLASS.
. Proctor, T . M .
.
Pliys. Rev. Letters, 3, 575 (1959)
Eloctrical polarization is found to be induced in a lead silicate glass by action of
X-roys.
'
H-5
I
X-RAY INDUCED ELECTKICAl POLARIZATION IN GLASS.
Proctor, T.M.
f|,ys. Rev., 1J6, 1436(1959)
Msasuroments on polarizution ond charges induced by X-rays aro reported. Charges ore
mcosured by healing the previously irradiated samples ond measuring the ensuing discharge currents. The effect is attributed to the formation of dipoles.
R
rOYiJSll PROiAKJIl.-G SHIIiLU POP. tiViSlü KSACTCHÍJ
B.Kaab
nucleonics 21,No.2, /J6(l?63)
Charged radiation from reactors io used to produce
currents in a dielectric reactor shield.
A STUD* OP SELP-POWJIiliiD DETECTORS I'OH MIXED 1IEUTE0HCiU.li.iA RAJJlATIOH i'lKLDS
G. Ramirez, L. Jtovid
llucl.Inatr.Methods 8£, 279 0-970)
Dept.liuclear and Reactor Physics,Instituto Venezuelano
de InvcfitigaoioncB Cientificas, Caracas, Venezuela
Properties and behavior of solf-po^erod detectors in
a mixed n-gami.a field are studied. Various elements
are used as electron emittoro to find beat suitable
electrode coupler for neutron detection with very low
fjainma sensitivity- U B well as for pure eaiarca detection
only.Construction, experimental results, and analysis
of response data are discussed.
\
048875 Ramsey, N.W. (Charing Gross Group of
Hospitals, London (UK)). Dose nicpsuranenl hy
Ihcrniall) stimulated tundmlivitv - a new method ot
düsimulry.
Kadefors, K.; Magnuswn, R.I.; Pelersen, 1. (cds.).
Chalmers Tekniska llocgskola, Gocicliorg (Swcdiii). Digest
ot the third international conference on medical physics,
including medical engineering. Cioeteborg. Sweden, July 30
- August 4, 1972. INIS-mf—52-1. 1972. Paper 22,7.
Published in abstract form only,
accuracy: dineiiieti'rs; dosimcuy: electric conductivity;
irradiation; pulyctltykncs; radiation doses; sensitivity.
17791
DETERMINATION OF MEGA-VOLT ELECTRON
SPECTRA FROM DOSE DEPOSITION PROFILES, Rauoh, J. E.
(Lockheed Missiles and Space Co., Palo Alto, Calif.). IEEE
(Inst. Elec. Electron. Eng.), Trans. Nucl. Sei., NS-15: No. 6,
322-35(Dec. 1968).
From Annual Conference on Nuclear and Space Radiation Effects, Missoula, Mont. See CONF-680706.
First, the equations are developed which are needed to compute a dose deposition profile from a given electron spectrum.
The dissipation distribution in aluminum as a function of electron energy is considered as the fundamental parameter used
in the calculation. Modified Nakai values of the dissipation distributions are used. Next, a brief account of the actual calculations used in the computer program is presented with a sample
case for illustration. The uniqueness of the spectral determination is discussed by considering the results obtained by three
different initial spectra. Although the final spoclra are different
and contain many of the properties of their respective initial
spectra, Hie calculated doses correspond to tho measured doses
extremely well and the same mean electron energy is obtained
in all three cases. The use of the resulting three final spectra
for tho calculation of dose deposition in high atomic number
materials is illustrated by showing comparison deposition calculation!; in aluminum and tantalum for the three spectra. The
agreement of the calcinated dose deposition for the three spectra
Is very good. Finally, an appendix is Included on the experimental measurement of dose from a pulsed electron source using
thin calorimeters and blue cellophane, (auth)
SHI
i5Jüivi:uovr.T o? ^ÜÍILÍWJ^ICS i>us TO PULSED KI.UÜVÍÍOITS
d .~£• Jíauoh, A. Andrew
IEEE Transactions ITucl.yoi. ITS l_3.i;0.6,10<;(l ^66)
Measure: ic;nts on Plosciglas wc ?c nade -aiti: a 2 1-loV F&V^ron producii:;; electrons with a maximum energy of 1.9 Mey,a rather
broad spectrum, and. secondary Kiaxír.m:.; at 3. >f\ MeV.íi; p.íiianoouu
breakdown was induced with minimum flux of /r. 1x10*"'" Co\il/n '
011 l//j inch diauator area.To measure charge buildup, I nil Al
foils ifcre ei.ibcddcd at varioiiü depths in dielectric,connected
to ground. Vi.th auoli foilo tho rad.inauced darkening oy.tcnded t
to {jreator depths then witliout the foils; vhich avoided charco
buildup.Ciiarao buildup were measured 'by a 50 Oliir. Grounding
resiE-tor,wonitoriny its; volta&-o,an.d integration of the
current-tine curvejassumin£j tliat this is inclicattive of charge
deposited in one hald of sheet in front and one half behind
the foil.ünorey deposition was measured with 10 mil thick,
coloring,inserted,filters. Charge builup prevents energy deposition from reaching cane levol behind thicker samples. Multiple meacuresi did not introd\icc; new brcal;dovm pattei's. Since
a nonooncr{jetic beam is absorbed in a S-shape,charge denni] charge dei:oity decreases vrLth increasing depth.Tho field peaks\
j atjsurfaco of incidence and goes through zero at at center of '
space charge region.Thus breakdown initiates at surface._ It
is concluüed that the surface field for breakdown initiation
is about 1.8x104 v/mil irhich exceeds the usually given value
of 400 V/mil of plexiglas. To study breakdown effects,potentials
on collection foils placed at back of samples vrere monitored.
Breakdown v?as observed about 30-40 ns after main charge
deposition, with a rise time of 10 ns«Cj,arge buildup vas found
to play a role in increasing the absorbed charge density. Multiple breakdown paths perpendicular to the main breakdwon plane
show the existence of highly charged regions outside that plane.
RADIATION EFFECTS OH GLASS
REIC Technical Liomo No.9
•
'•
(
AD 207701 Defense Documentation Center,Cameron Station,Virginia
MIGRATJOIT iUTD TliAl-'PIIiG- OF EXTRI1ÍSIC ClLUiGE CAKHIERS HT
POLYi.JEi; FILMS
A. Reiser, il.W.B. Lock, J.Knight
Trans.Faraday Soo. _8,2168(1969)
The behavior of thin polymer films charged negatively in
air by a corona discharge is described quantitatively in
termo of diffusion and trapping of the extrsinic charge
carriers.Mobilities between 1Q-9 and 10" ^ cra2/v sec are
found to be field-inuoponaent up to io5v/cm. Subsoeuontly
they become linear function of tho field, iheir ter.perature
dependence is described by an Arrhenius >Jg, .OhaiYje trapping
is indicated by a persistent residual potential. A mathematical !.:oJ.el is developed which assumes a) a single charge
layer penetrating the dielectric without trapping or
b) partial (weak) trapping. In neither case is the contribution of intrinsic carriers considered.
Sllf
Bulletin Aia.Phys.Soo. lfi^Ho.3,433(1973)
GC G
Fjiotoamisslon of Charge Carriers From Metal Electrodes info Poly_(N-Vinylcnrbazole).* P.J.KEUCROFT and
S.K.GHOSH,jjnj-Vj...of, Kentucky --Photoor.iifislon of holes from
the metnl electrode in motnl-FVK-SnO^ film samples (30^)
with high work function metal electrodes has been investigated. Photoeminaion thresholds were found at 1,4, 1.7,
am! 1,7 eV for I't, Au and Ac electrodes respectively with
thfi metal electrode at positive bi3G. The threshold obtained with Mg electrodes at positive bias coincided with
the photocurrent threshold observed for all.samples with
the metal at negative bias and for SnO.-PVK-SnO2 samples.
The lntter process is due to a photocarrier generation
mechanism involving electronic transitions in the polymer
and onsets at -1.9 eV, Photoemission of holes from the
electrode thus cannot be readily observed if the metal
work function is less than 3.8 eV. The photoemission
studies and eturlies on the dark current-voltage and dark
current-temperature characteristics in PVK films(l) support SchottkV-Richardson field-assisted hole emission as
the best description of the dark conductivity characteristics observed^ in PVK films with l't, Au and Ag electrodes.
ELECTRICAL EFFECTS OBSERVED IN IRRADIATED RHOMBIC
CRYSTALLISE SULFUR
B.C.Ribeiro,P.V.Murphy
An.Acad.Brasi.Ci. 3
Single crystals of low dark conductivity were irradiated
with -^°Sr bota rays.Induced conductivity was proportional
to done rs,te and field.TBOE}IXX Activation energies of
SaüosssSxQxxxxxx the order of 0.1 V wcro observed.Persistent internal polarization could oe induced by simultaneous action of an electric field and radiation. 1'h.o
polarization d^cay curves \fere exponentials v;ith an
activation energy of Èx$2x about 0.9 eV at room temperature .
EFFECT OP OHAIÍBER VOLTAGE ON ELECTR01Í BUILli-UP
J.E.Richardson
Radiology 62,584(1954)
Observations on polarity effect due to secondary
Compton electron production in the wall of ionization
chambers.
28413
CAftAlKH LIFETIMES IN y-IRRADIATEC AfjrHRACENE. Ringel, H. (Qiioens Coll., Flushing, N. Y.); Whitten,
W. B.; Damask, A. C. J. Chora. Phys.; 52: 1956-9(15 Feb 1970).
The effect of s0Co gamma rays on the lifetimes of photoinjected
electrons and holes in anthracene has been studied. Reciprocal
lifetimes of botli c a r r i e r s vary linearly with dose. Steady-state
space-charge-limitud current measurements gave a production
rate for deep electron traps of 1.4 x 10* cm" 3 • R"1. The variation
of lifetime with dose is interpreted in terms of radiation-produced
traps with trapping cross sections comparable to the geometric
cross section of a unit cell, (auth)
lltii "lot ]..ao.?3-c.'0( ('uini',3, Ai.j Hv-v..
(
)
CuMo í.;'Iaf.s s i l i c a were; exposed to v a r i o u s (iooc;s up t o
/&fl J..R. j)ir.;cna?-;;o mm induced by an impact probo anel dia—
clicr^o p a t t e r n : ) obsorvsclt .Jffeot of composition, of cerium
c o n t e n t , o f It-fd ooiit.uirl, physical dimonaions, and doi'isity
wciro uTjíitürvcd :UK1 dicohcr^o í.hrüsholdü dotovniincd. A
matbciüaiicaT i:,odt-] impDyin,;; t h e forrnution oi' r^tViation—ind
dipol'.iS Í K Í K Í X U uwvolopt-clj
d i a t r i b u t i .jn and po iw
EXPERIMENTAL ANALYSIS OP GAI#ÍA BATTERY
P.Rodriguez
Reps.I-IV,Nuclear Engineering Program,University of
Illinois,1963
C/tLCTiLATinN C? TIK. LFFTOJU'CY OF rP.'TT-;
Actn C i e n t . V e n e a o l .
\ r
KUOUJA*'. IJ^TTiJ
li
BREUSSTRAIILITJIG SHIELDING FROM ELECTRON TRAPPING
IN liIELECTHICS
D.L.Rollie
Nuclear Technology 10,325(1971)
A s-Uidy is made of utilizing electron trapping in
dielectrics as a moans of reducing toemsstahlung in spacecrafts at synchronous altitudes. Traps retain electrons,and
large internal fields are induced within the dielectric.
Electrons penetrating the insulating material can lose most
of their kinetic energy to the electric field with a subsequent decrease in energy loss to bremsstrahlung,reducing
production of the latter.It also lowers the average
radiation energy of that which, is produced, with consequent increase in probability of absorption by the
wall.Breakdown phenomena causes the the shielding effect
of the trapped electrons to be cyclic.A thin layer of
dielectric material on the external surface of a spacecraft should provide an effective,light,and inexpensive
shield against bremsstrahlung while not interfering with
any of the system functions.Electron-trapping shielding is
applicable not only in space,but wherever a dielectric layer
is allowed to accumulate.
" \
DIRECT CONVERSION IKTO ELECTRICAL ENERGY OP GAKKÀ RADIATIONS^
S/iITTUD BY NUCLEAR REACTORS OR R.ADIOISOTOPES
Carlo Roma
R&c.Sci.Rend.Sea.A,8.? 923(1965)
Describes a Compton current detector employing two metal
electrodes in vacuum ,one of which having a considerable
greater thickness than the other. A theory of (She device,
based on statistical considerations,is developed.
INCREASED CONDUCTIVITY OF SOLID DIELECTRICS ON EXPOSURE TO X-RAYS.
P.ow, C .
5ft Z?
Z . Pliys., 36, 10 0*20)
Aii OUi'LIITIS oy
S<X:]£ F,íC)1j.'ÜOGJÍDUC'ilXV£
A.lloiiC
RCA Review .12 ,362(1^.7)1)
Beth space clu-r^e u n i t e d and voluv;;o e x c i t e d c u r r e n t s
a r o GOm;iAcred. The n a t u r e of the l a t t e r acronan on the
vrorjonco and d i s t r i b u t i o n of t i r . p s , the n o b i l i t y of oiic or
"both Id. li d a of c a r r i e r s , and the supply of c a r r i e r s iroi.i
t h e e l e c t r o n or.. ilainl;' i n s u l a t o r B a r e conoicc-od . 'i'ho tv;o
t i n o coiiivthiitrj; i . o . t h a t f o r the oliscrvcu. decay oi" the
photo . u r r e n t ;.-.ni.i. the riean l i f e t i n o of the f r e e c a r r i e r , ' ; ,
a r e s e p a r a t e d . Xtcars (.'.isjcussed i n c l u d e a l s o ini'ru.red
oucncuiviG}i:i o c t r a l r e a... j!if;'.),non-u;ri:i'or:.-: illur-;iii.\t: ! .on of
cto.XTjp and tiio effectw of b i a T i t r f i e l d s .
t> 1
' '
KKCOi.lBIlíATIOÍT PfiOCESSlüS III I1TSULATORS AJJD Sü-iICOilüUCTORS
;
;
\
•;
:
;
:
:
:
;
(
i
j
:
A.Hose
Kiys.Hev. 51,322(1555)
Discrete states in the forbidden aone can be divided into
ground states and shallow trapping states, liajor recombination traffic passes through ground stat33. Shallow trapr,
causo the observed decay time of £XSE. carriers ±ÍÍX£JE.KEBOIduKüEHxiiaiiJi concentrations to exceed the lifetime of the
free carriers in the conduction band . At lo\r excitation
rates(free carrier concentration less than concentration in
ground statera) electron and hole lifetimes are independent
and fairly different.At high excitation rates both are
equal.For insulators having one class of ground states(class
defined by capture cross sections for holes and electrons)
the high-licht lifetime is bracketed by tiro lovr-light lifetines.-Lore than one class of ground states ir; required to
account for infrared quenching,auiierlinearity, and ability
of added ground states to reduce reconbination rate.These
effects involve redistribution of carriers amongst ground
states and give meaning to terms likd'filling of traps"
and "saturation of centers".- The capture cross section of
free states can range from Icr^oifi to arbitrary small
»
values.
\
37763
ELECTRON DEPTH-DOSE DISTRIBUTION MEASUREMENTS IN FINITE POLYSTYRENE SLABS. Rosensteln, Marvin;
Eisen, Harvey; Sllvermati, Joseph (Univ. of Maryland, College
Park). 3. Appl. Phys.j 43: No. 7, 3191-3202(Jul 1972).
Experimental depth-dose curves for 2.00-MeV electrons incident on layers of polystyrene were obtained for broad-beam
geometry as a function of slab thickness and incident beam
angle. Calibrated radlochromic dye films were used as dosimeters. Continuous spatial absorbance changes in the irradiated
film were recorded wilh the aid of a scanning densitonreter.
Data weru obtained for the following conditions: (a) polystyrene
thicknesses 0.42, 0.63, and 1.5 times the electron range, and (b)
electron-beam incidence angles of 0, 15, 30, 45, 60, and 75" to
the normal. Comparisons were made with theoretical depthdose histograms generated by the Monte Carlo computer code
ETHAN. Close agreement was found for the two thicker slabs,
but energy absorption in the thin slab was observed to be lower
than that predicted by the calculations by 5 to lõ%. (auth)
SvZ
CL
^
2
^
Isr/
TS JKJJUCI'Ji) III l'JUiumCAL CÁJilJiS BY
IttülATIOlf PULSES
US_ AKLitfíL
Teohn.Hep. 23131 (Sept.l$)62)
Current trmiiiients 'gonoratod in various types of eojnnierci&l
cables undor i r r a d i a t i o n from mixed gaj.iiiia and neutron pulse»
were ineaaured, as a function of voltage,distance from
source j and Dhioldingt lioafiurernonts with no voltado applied
were alfjo taken .Hnpoatcid exposures undor unchanged condit.iorip.
rni^ht lead to siro»i£j change a of the response cisnal ;evon
inversions of p o l a r i t y wore obaci'vod.
. RADIATION SHIELDING wIlJIO?/ GLASSES
I V/.S.Rotbwcll
j Corning Glaos V/orks,Res.Lab.,Corning NY
Description of 3 glasses developed by Corning.Their
properties.
S"t>
'\\\u i:ow-]..n;-:ün Í.-.LI-.OIVIC ii'.iLD 11? OTJ:.I;,CT;<TÜ3 i o u i z r o BY
RADIATION
A.S.Rozenkantíí
ii] ektx-ic)iestvo(USÍR) _6,52(1966)
Tlic r e v e r s i b l e ch^n£ccB i n t h e e l e c t r i c f i e l d due t o spaoc-char^o
r e d i s t r i b x i t i o n a r e oonwidered and t h e i r i m p l i c a t i o n s on
insulation,measuring inothods and automatic contacts are
discussed.
.
Si>b
\
IF/ESTIGATIÜN OP THS 3L3GTRIC CONDUCTIVITY -0? INSULATING
MATERIALS 33?0HE, DURING AHD AFTER IRRADIATION.
I.M. Hozman, and K.G. Tsirarner. Zbur. Tekh. Piz. v.2o } p.1661-83
1956. (Trans, from Referat. Zhur. Fiz. n.5, 1957, Abs.no.12053)
L
A desorijjtion is given of the application "of capacitor ionization chambers for the measurement of the electric conductivity
of insulating materials before, during and after irradiation.
The chamber is also used for the determination of the dependence
of the electric conductivity on the temperature. The construction of the capacitor ioniaation chamber is given. The
change in the potential of the chamber under the influence of
ionizing radiation is estimated. Measurements were made of
pressed amber, polystyml of different degrees of purity,
p^lyrnethylmetacrylate, polyethylene, and polychlorflunroethylenc.
and the results are tabulated. The reproducibility of the
measurements was shown to be good.
Sbl
/ ir
o
039179
Uozcnblytim, N.D.; Bclavin, M.Yu.; Milel'man, "
M.G.; Sokolov, A.P.; Pochivalin, G.I1. Influence
of cuinplon clettroiiN ou direct ihiirging detector seiiMthily.
(In Russian). VI iy an if kompionovskikh chlokirunov na
chuvswilcl'nast' DPZ.
Go.sudarslvcnnyj Komitct SlanJartov Sovcta Mritisirov
SSSK, Moscow; Gosudarsitcnnyj Koinitct po lipol'/.ovaiiiyn
Atonmoj lihncrgii SSSK, Moscow; Vsc&oyuznyj
Naucfino-EsslcdüViiterskij Inst. liziko-Tckhnichcskikh i
Raiüütckhniclicskikli J7incii'iiij. Níoscow (USSR). Neutron
radiation metrology in reaclojs and accclcnitors. Collcctiüii
of paper ahsiracts presenteei to the First all—union
coordination meeting on ilk* neutron radiation mctiology.
Mctrologiyu ncjlronnugu i/Iuclk'niya na rcaklorakh i
uskoriiclyakh. Sboinik IOÜÍSOV dukladov na pcrvotn
vscsoyu/nom koordinatsiotinom soveshchanii po mettologti
nejtronno^o i/IiiLlicniya. INIS-iuf™432. 1971. p. 48.
Published in summary form only.
compton effect; e/<?c(roiis; ^amma radiation; gamma spectra;
neutron detectors; sensitivity.
037365
Ro/cnblyum, N.D.; Ilahulcvich, H.N.; Alcksccv,
A.K.; Zagadkin, V.A.; Kirsanov, V.S.; Ku/netsov,
hh.M.; Kononovich. A.A.; Miid'nian. M.Ci. Kxpcrimenlal
tlv(crinii\ntimi o( the sensitivity of self-powcrcri detectors in
Iturnial uncl tpithcr/iKil regions. (In Russian).
HhskpLTimcntal'noc oprcdclcniu chuvstvitcl'nosti dctcktorov
pryanioj zarjadki (DPZ) v tcplovoj i ehpitcplovoj oblasti.
At. thnurg.
(Apr 1972). v. 32(4) p. 333-335. For
English translation see the journal Sov. J. At. Energy;
Lelter-lo-thc-cditor.
activation energy; emission; epithcimal neutrons; neutron
dejceiors; neutron flux; resonance integrals; rhodium;
sensitivity; silver; thermal neutrons; vanadium.
sb CI
I.
G;-:.'.I-IA Ü ; / P A U T O U TOR IIIG!{-I".;'ÍVM!SITY H A Í J I A T I C K
nio!.!, September
A device iti doficribou v.<hiohomerisured c
between 0.07o r / a o c £md 1 0 J r / s o o ;iiiilxKj;tr.:ce
independent of orsorgy botv/oeh 500 kV and 24 LlcV.
a t i t a n i u m envelop'-.',tvbich ESvtewj i s tho a c t i v e elo:i;ont, i a a
c o l l e c t o r o l e c t r o d o held i n place 'by a ceramic «pacer t h a t Í
sorveu alao as an i n s u l a t o r . The i n s i d e of the t i t a n i u m env<
envelope i s coated with a t h i n l a y e r of magnesium, oxido*
and magnesium o x a l a t e . 'Fno j-iaijiesiura-oxide l a y e r i s p r o c e isscd l)y techniq,tios developed f o r ma^ner.ium-oxide cold oai-hodo e l e c t r o n tubes . I n c i d e n t £U',ma r a y s e j e c t Compton
e l e c t r o n s from the t i t a n i u m eneveíope and titart
.
a m u l t i p l i c a t i o n prnoeau through t h e megnosiumcxido l;:yovo iíor.ponso ã s instentancouri cn:3 tho dovioo
i a p a r t i c u l a r l y r-.uitable f o r pulse measurements,
\
AJ? ELECTRON BEAM TííOiilflQUE FOR VISUALIZATION OF CUAHCÇ.C '
DIÍ3TRIBUTI0K
II. Sai t o
Japan.J.Appl.Pbya» 4,886(1965)
A?i electron beam io unod for scanning the charge. By its
deflection a characteristic pattern describing the
5~ff
charge distribution on the djelectric surface, io obtained
on a screen. Tho pattern is analysed in terms of the
interaction between electron beam and charge distribution.
Experiments on various charge distributions were performed.
3397S
(CEA-CONF-1508) EFFECT OF 1-MeV ELECTRON
IRRADIATION ON MOS STRUCTURES. MECHANISM OF FORMATION ANO THERMAL NEUTRALIZATION OF THE SPACE
CHARGE. Siminiictoyar, K.; Bernard, J . (Commissariat a l'EncrgiR Atomique, Grenoble (France), Centre d'Etuden Nucleaires),
1969. 17p, (In French). (CONF-69064O-1). Uep. CFST1 (U. S.
Sales Only).
From Conference on Properties and Use of MOS Structures,
Grenohle, France.
Transistors and capacitors of very fimplo geometry, formed
with a layer of wet thermal silica and a layer of aluminum, were
irradiated by 1-MoV electrons. The threshold potential of the
MOS transistors and the capacity and conductance of the MOS
capacitors were measured. The phenomena of formation of the
space charge zone with both continuous and pulse polarizations
are presented. Mechanism of the space charge annealing during
the thermal annealing process is explained. (France)
I
§ / '/
"*
\
GAUÍA-EL3CTI1IC-CELL THEORY AHD KXPIKEKSMTS
H.T.Samoson
573
Abstracts,Fourth Ann.ASS Study Conf.,University of
I l l i n o i s , April 22-23 (1966)
f UIGíí-VOLiViJE G/J.J.-.^-Bf.KCj'jriC CiíLL Ol-iJIUTlülí
í II.T.ÍJMIVL-OU, G.il.l-lilc;-
Unclear applications £, (September lS)63),l4
Stable voltage outputs exceeding 10 kV have been obtained
•s-fitii two Lvuliicol.l octor ht-nna-cleuiric c e l l dnai^u; using
cpo.r^ 01- pcuyctyrene d i e l e c t r i c . Short c i r c u i t currents ranCed i'ror:: 3 to 5X1G-17A/CU2 por R/h.Voltage broa];do-.;.-i and
e r r a t i c output, observed i n certain coll dotsiyns and ranges
of gíiv.m;: dotio rate;:., are a t t r i b u t e d to r a d i a t i o n effects 3 iu~
cludiii;;. induced polarization of the d i e l e c t r i c . A tiieorv
for hi<;h voltado operation,involving both the c o l l e c t i o n
of Cor.pton clcctrcno and leaJ.ace current:.;, i s developed.
T
!.T.:;r-N'.i5on G.TT ],;Í]OV
Transactions ANS £,337(lS66)
;.!e;ir;i.v.-i:;:iO.its arvf reported for BJ.1J:K:1I:Í'/.:•:! colls
witlj c,ylir,r!r:i cf'i (ilcctrodtsK arid a 1 c í—disc bffoí;: pinte
to m\r>iuázfí secondary electron losces asaocii'tfcd -,.-ith
triiiu.-.mittofi parn^ia r-uiiatior, ..•iii^nsionr- are a3j 5 y. 8 incho
Triga vnacto:c i r r a d i a t i o n and ° Co f v-cil i t i e s have
boon u'iodj 'vith ''OBC rates \xn to lC-'Ii/h. Diolootrsos
u^ofl v.'cre polystyrone and f;j]icone rubber i n s u l a t o r s .
For ].0'r:?/h rnaA.u-iu.-!. voltaccs of nearly 1'j 000 V v/tro
found idetorioii ation of the d i e l e c t r i c cauaed ,1'o."overj
the volt-.i.e to decreane after the peal-: had been
reachod.l or 2.5 y ICMR/h a stable voltage of abovrt
11 000 V v/aa obtained with polystyrono. A new theory
v/as dovolf'pod for the opeti—circuit behavior. Calcuationo
wore coded for the IBM-7O9<+« I n i t i e l oalculetions for
0.662 "eV ga'wnas yield 0.55 x ÍO"-1-^ A/(cra2 IÍ h) for
a poiyotyrono c e l l at 0 and 1500 V respectively,Iri
contract j ritiOrt-cirouit r.urrents {,f 2.5 x lO*"''1^
k/{oisP- R h) for reactor i r r a d i a t i o n and O.46 x 10" ^
A/(om2 I? h) for °Co were measured.
Tcmner.Kiirc drpcnilrllK of Ilic carrier pcncrnlion yield in decironbomliardccl
\/ niillir.nccnc. B.Smral (Insl. il'I-.uuics Nuclcaircs, Algeria). M.Sclio«. Solid
V SlaliCi»iiuuin.((-SA). voU8.no. !8,p.lW 501 (15 Scp;. 1970).
6"7i
!
r
[
^
01V THE CHAFGS OF THE DIELECTRIC L033 FACTOR OF 'sOIJE PLASTICS \
UNDER GAMMA RADIATION AT 9 . 4 GHz
. . '
IL. S a u e r b r e y . H. Suhr
Koll.Zeitschrift tind Zeitschrift f.Polymere
215 ,127(1967)
S7V
/
/
29983
l'KE-EXPONENTIAL FACTOR IN ELECTRICAL
CONDUCTIVITY OF IRRADIATED POLYETHYLENE. Saiva,
Goro (Nagoya Univ., .Japan); Kitogawa, Keiichi; Ieda, Masayuki,
Jap. J. Appl. Phys.; 11: No. 3, 41G-17(Mar 1972).
In tlie temperature range well below the melting pninl, the conductivity of a sample of mmoaltd polyethylene can be expressed by
the formula v - o$ exp (—tJ/k'l'), where <r0 is constant, k is Holtzmann's constant, T in lhe absoluto temperature, and U is the apparent activation energy, Kxpor.ure to ftamma radiation changes
both U and o 0 . A plot of log o0 vn U yields a straight linn for the
irradiated polyethylene, hut a plot for the unirradiatod sample is
somewhat off this line. For the irradiated polyethylene the compensatlon rule, log <r0 - ft + (JU, applies. It was found that, for
polyethylene free of additives, the compensation rule holds for
different radiation doses hut not for zero dose. This result suggests that the predominant conduction process may be different
for irradiated and unirradiated polyethylene. (R.W.R.)
T7PV IO
INFLUENCE OP X-RAY AND GAMMA RADIATION O N THE CONDUCTIVITY OF
PARAFFIN WAX.
Seidl, F.
Z . Phys., 73, 45(1932)
In liiii and following papers the effects of X - and comma radiation on conduction in
paraffin, amber, and seignerte salt is investigated. In particular transient effects are
studied. Effects are reversible in so far that dielectrics recover fheir original properties
after irradiation has ceased.
NORMAL CONDUCTION CURRENT AND DELAYED EFFECTS OF SOLID PARAFFIN
EXPOSED TO GAMMA RADIATION.
Seidl, F .
Z . Phys., 99, 695(1936)
Sofh conduction and absorption ore found to increase, Prolonguod irradiation results in
fatigue effects.
Bull./ai&r.Plij-s.Soc. 15, lio. 12,1590(lS70 )
Sol
AD 1. Theory of Pulse Induced Transient Photocurrents
in Insulators. II. SEKI and I.P. BATRA, IBM Research,
San Josc--The transient photodischargc process in a
photoconductoT-dielectric sandwich structure due to
pulsed light is analyzed. It is assumed that the light
is absorbed at one of the surfaces of the photoconductor
layer and its duration is short compared to the transit
time of the leading edge of the charge carriers. The
theory is developed for one type of trap but can be
extended to multiple trap types. Time dependent
approximations which give the upper and lower limits of
the observable parameters are derived up to the transit
time and beyond.in some cases. It is shown that the two
limits arc sufficiently close to each other under a
rather wide range of experimental conditions so that
important transport properties such as mobility, lifetime
and trapping times can bo experimentally determined.
Examples of calculated results arc given for cases
involving one type of trap and two types of traps.
ELECTRON TRANSPORT IN PVKfTHF
H.Soki,W.D.Gill
In12nd Int.Conf. on Conduction in Low Mobility 1-iaierials.
Eilat,Israel,5-8 April 1971* Taylor and Francis,London,
Electron transport proportios for electrons in this organic
photoconductor have been determined by measurement of trans
ient currents duo to pulsed illumination.Analysis in terms
of a multiple trap theory indicates as main effects! intertrapping drift mobility and trapping and detrapping by two
sets of traps. Mobility,free oarrier lifetime,and and
trapping tines depend strongly on the field.
DUE TO PULSE ILLU1.ÍHÍATIO1T HI (THE
OF TRAPPING.II.
H.Ss!ci,Ii.Batra
J.ApploPhys. ^2,2/507(1971)
The transient photodischarge process in a photoconductordieloctráo structure is analyzed. Ligiit is assumed to be absorbed in a very thin layer,its penetration being neglected.
A one-level trapping model is discussed, which can however
be extended to several trapping levels. Solutions are given
mostly for times up to the tranoit time of tho leading edge
of the charge distribution.
<
IpirOTOCDRHSIT AM) CÂÍÍH1BR DISTlÜüüflON -WJE TO STEADY LIGHT
AjiâOKBííB 1IÍ FIHITE Till CJQffiSS
.
H.Seki, B.H.achechtraan
J.Appl.Phyo. 41,523(1972)
The rjtec.dy-sta.te current through a layer of jrhotoconJuctinf;
rsatorial ia investig.-tod v-iien 0110 surface is illui-inatod Vj
constant lijjht source,material being iutritisic unJ frt-o of
deep traps.Li£;lit absorption cLr.rac-icriaed b;v optical £;?;üorptio!i
coefficient,bulk recoubiti^.tion iü taken into account. :,"ith an
api-licd field th« c:cy&rir.ental3.;.- acceasible pr.otoinjectioa
efficione;,' is the product of free-carrier generation efficior.c;
and rocoMbination yields L'ono:;iolocular and binolecular cases
are discussed*
\
A STUDY OP THE INITIAL PHOTOCURREiiT DUB TO PULSED LIGHT
ABSORBED II? FINITE THICK2ÍESS
H.Seki
J.Appl.Phys. 43,1144(1972)
Paper investigates effect of finite light penetration on the
initial photocurrent for a trap-free material assuming an
initial exponential carrier distributiion in space and simple
bulk recombination. The initial current contains 3 components
e.g. a current duo to carriers which get photoinjocted into
the sample (constant), a current due to carriers of opposite
polarity collected at the illuminated surface, and a current
due to carriers which recombine. The 2nd and 3rd component
decay rapidly to zero. Cases approximating monomolecular
and bipolar ..recombination are treated.
Hi /
naiu.1 w i t - e r o i — i c s up t o
ÇuO keV Ijnvr, b3on ),iei>;;nrort i n r.bh-.orbt.-ra of ;'J , b . n s s , A;-,
'sv,/r>b ;m*. An. v:ijjc!?i for-i.v.d t h o •.•••ii)'3ov/ of a- 2 f e c o u n t e r ,
póct.-cnr/ :nv •tryy.wiiitt'.O. to a grsiitcr extent than cueoU'crm. .
LOUG-TEKli Ali'TKR-Bii'FECT CONDUCTIVITY OP THI1I FILMS OF
I ].ig FLUOKIMJ AlíD 2n SULPHIDE
| L.A.Serobrov,V.L.Shmulovich
Radiotekhuika I i.'lektronika_l£,1034(l969)
Par>er studies excess space charge from bombardment of
0-5 micrometer thick films by 10 keV e l e c t r o n s . This
forms a cathode o l e c t r e t of high i n t e r n a l r e s i s t a n c e used
for storage«long-time p r o t e c t i o n and subsequent reproduction
of s i g n a l s .
J1^
OF
jíLucriiar
C::AKGK3 P}ÍOJ>UCK:ÍJ OIT POLI1!ÚÍR F I L I S BY
Dler. J.'iout
Lütterr, 7,367(1967)
.on ani behavior oi' electrots pi-oduceu Toy electron
boi.ibardniont are diocuaaoá. Thin sheets of Teflon ?JiF,n:'lar,
and polycarbonate foilo wors used. One effect considered
wae secondary emission on the upper foil producing a
positive chare©. The foil is aleo exposed to secondary
emission end backscatterine ÍTOE: the plezi&Las plate. Surface
and voliuio recombination produce the polarity reversal
resulting in nonochargo electroto.
I
010VI
CUliVSS OP lil.hOTUOY.-BQlãiÃKu^V F01X-IEH
FILLS
G.I..Se«slcr, J.'ietst
Bull. Av.. Ph;vs. Soc. 15., Ho. 3,307 (1970 )
UM J
* Con^^c't-lV-i't-y Glow Curves of Electron-Boiribsrded
Polyner Filr.n. G- M. SES8LER and J. E. WEST, Bell
Telephone Laboratories, Murray Kill, R.J»— Space
charges injected into 2 to 25JI polymer films by means
of nionoenergiitic electrontoea'its(energy range 10 keV
to 1 MeV) have been investigated by measuring the
depolarization current as function of time at increasing ter.; erature (conductivity glow curves). The glow
curves indicate multiple trapping levels for electrons
at d t ; ^ : of between 1 and 1.5 eV below the conduction
band for such polymers as polyethylene terephthslate
(P5.T) , polycarbonate, and polyfluoroethylenepropylene,
The trapped charge density appears to be greatest on
the thinnest films. Typical initial full-trip densities on 2\i polycarbonate and 3«8ii PhT? are 2.lX10l6/cni
and l.Dao3w/cw3, respectively. This is within the
expected range.- oi" trap concentrations for low conductivity materials^- and about an order of magnitude
higher than previous experimental results^.
J. P. Fowler, Proc. Roy. Soc. (London) A236, k6h
2
l» K. Monteith, J. App5rt-PhjB. 3,7, 2633
„
ek-AliGIlíC? 01)' I'CLYl-iEH FOILS V:XTlf kÜlíOEKiiSCtórlC LOV^-üvüJiíGy
BL-JiCl'ROTi BEAi:S
G.LI.Sect;!cr, J,1!cst
A p p l . P h y s . L e t t e r s 1.1,507(1970)
Resulta of charge d e p o s i t i o n on 12.7 and 25-4 nico.uotcr
pol;,i.iõr foilíi v:ith -,;ith 10 to t\0 keV e l e c t r o n s a r e r o p o r t e d . Sio trapped chargeB Jiave densitio;:. of about 10
CoiQoi.ih/'ci.'i''-',. irith cro.?. iniiforiuity of about lj/., The tii.o
c o n s t a n t s of the' cli.ar,-jo decay a r e of the o r d e r of tons of
yíarsi.Cond\:otivity ;;loir curves ;:•.':.ovr a wore denacly
povjilated )ji-;;h--"tei.]i'c:;.ia.tiu:e p o r t i o n tjis.ii ^;lo\r curves f o r
o t h e r .Viet/jods of cliav;>nü.
CÍIAlíGH M C A Y CHARACTERISTICS OP P0I.Y1.1ER FOILS
G .1-i • üeüfilor, J. K. i.'oat.
1970 Annual Rep. Conf.El. Insulation, líatl.Acr.d.Soi.,
Víáííhini-ton DC 1971» P « 8
Foils vrere charged by t>reakdovm and by electron 'beam irradiation.lnateriala included 12.7 and 25.4 fira foils of
polyethylene tGropht}ialate,polyfluoroehtylenepropylene,
polytotrafluoroethylene, nom.ietallied or uotallizcd o n one
Burfaoe.Current densities u p to 0.1 uA/cn \?ero used.Breakdown charged foils gave u p to' 1.5xlO~" 0/cni2,others about
10~7 c/cnn.cfi'artie densities were neasurçd with dissectible
capacitor orAan«ncon"ia</«a method,as reported P.ev.Dci.Instr.
KLecti'-on onorcxea were up to 2 8 keV.Beara-charyed foilc
keep charge better than thernocharged ones.The initial
charge decay was measured tlirou^i conductivity iiioanurementSjaa a function of voltage generated across f o i l . Conductivity was measured by measuring the displacement
current between electrodes placed on both sides of the
foil (p-^esuniably íoncontactinü electrodes).Uleetron
conduction was inferred . It is stated that?"The integrated
current,correctod for foil-electrode spacing,equals the '
total Measured surface charge". B.ectron beam
\
charged foils,studir;.. -by thornally stimulated currents,
'
ehow prcyondoranco of high temperature peaks. The average
penetration depth of ^loctrous vrao determined assu.'.;in;^ t}iat
Tíith churco clouds near one electrode practically all charge
r.ii.j,T£.tce to the ric.!.vrest electrode, as h a s been proved by
oevoral authors. Cnce the discharge currant is intermitted,
a second ti;.;e the iiidticed charge o n a n opposite noncontactin^
electrode.Average penetration depth is found to exceed
electron rance,r::ainly for low energy electron energies,due
to bulk i'otrapping of electronr: initially uepooited r.sax'
the surface.
t
CHARGE DECAY CILUUCTEEISTICS O P POLYi-SR FOILS
G.L.Seüsler, J.Viest
^
....
Annual Kep.Conf.3il.Insulation 1570- lTtl.Acad.Sci.,J*tl.
Res.Council,',;aehir;r,-ton DC IS'71) P«0
\
Foils irerê charged by breakdown and by electron i r r a d i a t i o n . ^
Tho average cliarge depth ira.s dctorrãned by a combination
\
of the chE^fje induction and the current therraoáepolariaation method.
CüÂlluE HíOPKRíXKi Oi' KL!iiCTiiOir~-5Jiiü-i liüüúÜATrü)
MAúh^S.i±{yà
Sti: "i-jl.=:ctrcto,Chnri;e Storc..-.;o VMÍ Vraar^.-ort in J,i oloetrios;",
Conf .,i,:Lc:i,,i October 8-13 5 lS?--' ExtcnO.ed Austrncts, 3M19.
'i'hc '^ Gotrocheuioal Society.
1
i
ON THE APPEARANCE OF AN EMF INCIDENT TO ANNEALING
OF THE BETA-IRRADIATED ALKALI METAL HA.LIDE
CRYSTALS
VoAoShJbaeVjV.PsAvdonirijI.A.Vasilev.G.A.MikhalchenkOjBoT.Plachenov
Iav.Akad.Nauk. SSSR , S e r . F i z . 30,679(1966)
I f a c r y s t a l i s i r r a d i a t e d a t 9QSK and subsequentlyheated, a free charge i s observed on t h e surface of
the c r y s t a l facing the source.Sfcxs The corresponding
enif i s called thermostimulated c o n c e n t r a t i o n emf.
The charge was c o l l e c t e d on an e l e c t r o d e covering
the sample and measured by using a compensating
voltage.Simultaneously g i x luminescence glow curves
were measured and fourld t o peak a t about t h e same
temperature as t h e charge. I t i s believed t h a t the
e f f e c t i s due t o a non-uniform d i s t r i b u t i o n over t h e
sample th'ickness of tra.pped c a r r i e r s .
GA1.ÍMA-MDIATI01Í-I1JJJUCED rUKEEIiTS BETWEEN INSULATED
DISSIMILAR ELECTRONS
E.B.Shields
AEC1I-VJ64 Report Ator.iic Energy of Canada,Ch2.1k Ri*vcr,ont.
July 1570
Results of an experimental study are given. The principle
variables were electrode me.- rial and thickness, geometry
and insulation. J.n attempt to rationalize detector behavior
with respect to the analytical rodei proposed by Sovka and
i'ruant hac been moderately 3uocessful. Son:c considerations
are given to problems of spectral response.
- Measurements
refer to Pb and Al electrodes, polymeric insulators(lucite,
polyethylene,) radiation from a "°Co source, dose x-ates
of the order of 10^ rad/h. Insulator thickness wao 0.002 in.
but effects of varying insulator thickness vrere also investigated and indicated presence of very weak radiation
(since 0.005 in. insulator gave already an output decrease
of 25/í. Radiation-induced insulator conductivity was also
i n v e s t i g a t e d , b e i n g ohiaic and p r o p o r t i o n a l t o dose r a t e .
TRANSIENT CURRENT FROM PLASTIC INSULATORS AND ITS CHANGE BY
dáiffiA RAY IRRADIATION
Shigeru I d e , Tatsuo Urai
Chem.Phys.High Polyraers(Tokyo) 20,583(1963)
Thiçj, p l a s t i c films were i r r a d i a t e d by n e a r l y 3 Kft. Before and
a f t e r i r r a d i a t i o n a CRIÍEÍE dc v o l t a g e wa3 a p p l i e d . TkKxiixsT r a n s i e n t c u r r e n t s were observed f o r p e r i o d s between ?0 and
lo3 s . They were found t o follow a t ~ n law, ÍIÍBXEZPKKEII*
SiX}iáia±±HKxni}iiitExi±SEifxÍB±txiaHÍy An e f f e c t of i r r a d i a t i o n
was observed, b u t was a l s o fiund t o disappear soon a f t e r
cessation of irradiation.
\
SiA'i'ISTICS Oi' Tiíü ItECC);.J3I!JATIOJT Oi' HOLES ASD ELliCTHOirs
Vi. Shocklev,;;. V .Uead, J r .
()
'1'iic s t a t i s t i c s of the recoiobination of holes and electrons
in comiconductors i s analyzed on the busis of a model
in which tho recombination occurs through the mechanism of
trapping» A tnvp i s astmuod to have an energy l e v e l in
the GiiorQ- gap no t h a t i t a charge nay have c i t h e r of
two values d i f f e r i n g
by one e l e c t r o n i c charge.The
dependence of l i f e t i m e of injected c a r r i e r s w.ori
conductivity twii upon injected c a r r i e r density i s
discussed.
I* BAUVPERISS» it SURVEY
lwlV7c,on?..on
P-accful U^es of Atonic Bn-rry,
Geneva 1956, Vol. 1.5,p. 310
IONIC CONDUCTIVITY AND TIME-DEPENDENT POLARIZATION I N NoCI CRYSTALS.
Shutter, P.H., Nowick. A . S .
J . o p p l , Phys., 34, 734(1903)
Systematic study of dc polarization and conduction effects, Including test of validity
of superposition principle, investigation of analytic expression for transient currents,
and effects of X-rodiation. Prolonged X-radiation (114 h, 40kV, filtered through 2-mm
thick NoCI crystal) produced strong increase of transient currents measured ot V4°C,
without changing the shape of lhe current-time curves. This indicates that although the
polarization is strongly enhanced, it is still characterized by the same broad distribution
of relaxation times as in lhe non-irradiafed material. Optical bleaching produced only
a slight reduction of polarization, while annealing at 110°C for 12 h produced a substantial decrease. A model is proposed v/hich explains polarization effects by the
presence of large clusters of defects.
I
21001
CONNECTION OF THERMOSTIMULATED CUnRENT
IN IRRADIATED POLYMERS WITH MOLECULAR MOTIONS.
Siehkar, V. P,; Vaisberg, S. E.; Karpov, V. L. (Inst. of Physical Chemistry, Moscow). Vysoltomol. Soedín., Ser. B; 12:
510-12(Jul 1970). (In Russian).
Experimental data were obtained for the thermostimulaied current in y-irradiated low-density polyethylene, polypropylene,
polystyrene, poly(trifluoroethylene), poly(tetrafluoroethylene), and
polyívinyl chloride) films, (tr-auth)
>~Q~7
**' i
^ ~
_
JTQÜ
*'- / o
THE PHYSICS OF FAILUEB OF KIS DEVICES UUDER RADIATION
\
A.G.Holmes-Siedle, K.H.Zaininger
• j ...
IEEE Transactions on Peliahility R-17,Ho.1,34(3-968)
MOS devices undergo a change of operatiing region,this Tseinj
in the natuaio of a shift of the characteristic curve of
the device, produced by the trapping of radiation-induced
holes -within the 2000 A° insulator and the consequent
build-up of a fixed "bulk space charge in the insulator.
077
Variations in the shape of the of the characteristic
curve and increased leakage current are also observed.
2/32
(N-66-2GG03) STUDY OK CI1AH0U STOHAGE IN
SIMOON OXIDU HKSULT1NG FHOM NOV-PIiNKTIIATlNG ISL1ÍCTHON IHHAUIATION. Simons, M.; :,iontcllh, I,. K.; Ilauser
J. H. (Research Triangle Inst;, 1) irham, N. C ) . Juno 1908.
Contract NAS1-6900. 78p. (NASA-CH-1086). CFSTI.
Charge storage In silicon dloxidi resulting from low ciieruy
electron irradiation has boon observed. The positive charge
build-up has been studied in MOS typo structures for various
oxide (hicltpcssei ; a function of beam energy, electron fluence
sample bias, electrode thickness, and a number of Dxide-rclated'
parameters. The effective mdinfion-induced oxide charge appears
to be a function of beam encrsy dissipated within the oxido near
t in oxide-slllcon inU-1'fnroi this charge increases with electron
fluonco up to a saturation lovol which won oboorvod in somo otcamgrown oxides; the (wporlmcntally observed dependence of induced
iliartfc on applied bin» Is compared with that predicted by several
models for charge accumulation. Optical and thermal anncallnj;
of the trapped charge lias been stuJied in an effort <n derive Information on the nature of the oxide trapping levels. Reduction of
trapped charge by Irradiation at small negative biases has also
been oxploiud. 1'lnally lhe development of a two-carrier model
for space charge build-up in an MOS structure In discussed and
the experimental results obtained for silicon dioxide arc related
to device performance in tlm rnrllniinn f.i,,jii-r,nm<t.i (•>...M « T < I »
/ ,>ri
f> ('<'/
1
•.
s o n OBR-litVATIOlIS ON CHARG".? BUILDUP A'iD E'dTiK:.::'-: HCl
SILICOK DIOXIDE IRHADIAT]-]]) WITH LOVZ-KHIHGY
ELIíCTiíOIía
I.I. Sp.riions Jr.L.K.IiOTitoith, J.n.HmJEJOr
IUKE Trans.lOlontron Devinen, ED 15_,
The p o s i t i v e charco lDuilá-up produced by 0 to 50 V.cY
G 1 ee-kror?•{'•'"ia I n v c c t i g a t c i a?, a function of hop:?.
energy avid oxido t h i c k n e s s . Uanie laeafiufornentfj v/i-!-h
hi^hei' energy o l e o t r o n s are a l s o r e p o r t e d . T h e ii ';.r.>dnce<3 charfjo, as ne«.s'urcd fron displacement
of
c a p a c i t a n c e v e r s u s v o l t a g e plots,war: found t o br- a
frmction of beam energy d i s p i p a t e d w i t h i n the oxidç;
in the v i c i n i t y of the OKid«--silicon i n t e r f a c e .
At a £ivon f l u e r c e l e v e l , i t increaorsj v/ith eT-fr^y
( a t c o n s t a n t thickneBC of sa/rplo) up t o so.ife ' o v . 1
Umax beyond which charge b u i l d u p r a t e f a l l s off
as~the bean energy i s i n c r e a s e d furthermore.Continuai
f a l l o f f i n the buildup r a t e v:as observed i n
s e v e r a l snraples i r r a d i a t e d a t e n e r g i e s of 200 keV an
-J.fe¥-.íanx^afufaung^to correspond to _ the bosnt
which according to predicted range—energy data,
produced maximum energy dissipation per unit length i>.. the
oxide near the EUEEEECÍHS; interface.The charge in oataples
irradiated at these higher energies was considerably more di
fficult to remove. From 30 to 60 min at 300°C was required
to completely anneal these u n i t s . The introduction of deeper
trapping levels associated with localized defects produced i
in the oxide by the high energy electrons explains t h i s i n creased difficulty in annealing. Isochronal annealing of
samples irradiated tit both high end low energies v?as performed to obtain an activation enexiey for the trapped
charge. Constant—temperature annealing i s linearly depending
on the logarithm of the elapsed ti:;:e over a f i n i t e interval»
Such a function can result either from thermal activation of
trapped carriers from a uniform trap distribution or fr
thermal emission of recombination electrons over a
Schottky barrier from the silicon into the oxide»
10249
ENERGY 11EPOSIT1ON AND PKKJ-.TliAXIOM DEPTH
OK HEAVY IONS IN ELECTRONIC STOPPING lil-JGION. Sigmund.
I'.; MatUiicr.. M. T.; Phillips. D. L. (Argonno National Lob.. 111.).
Badlat. Eff.i U: No. 1, 39-19(Oot 1971).
Previous calculations of spatial moments over the distribution of
ion ranges ami bombardment damage wen extended into the range
of ion energies where electronic «topping is important. Numerical
solutions nru glvon of well-known integral equations, under Hie assumption of Thomas-I'ermi seaUc-Hng and velocity-proportional
electronic stopping, for Mjual masses of ion and target and five
values of the electronic stopping constant, over a range of four
decades of ion energy. The results are compared with experimental damage distributions, with good success. Implications on
sputtering: are mentioned briefly. (autW
.
.
,
OD Í
/"
!,
'/
HAPID A1Í1TEALIWG OF PULSE RADIATIOlT-IliDUCED SPACE CHARGIÍ
}
Hi SI1JC02Í M0XJM5
M.Simons
(lios . T r i a n g l e I n s t . I T . C . ) H.L.IIuclios
Ii.L.Hughocj
J . A p p l . P h y n . 4J2 ,3000(1971)
(June)
*
r
v
b0?>
1
/
i
-
43123
SHORT-TERM CHARGE ANNEALING IN ELECTRONIRRADIATED SILICON DIOXIDE. Simons, M. (Kesearch
Triangle Inst., Research Triangle Park, N. C ) ; Hughes, H. L.
IEEE (Inst. Elec. Electron, Eng.), Trans. Nucl. Sei.; NS-1S: No
6, 106-12(L)ec 1971).
From Annual conference on nuclear and space radiation effecti
Durham, N. H. (20 Jul 1971). See CONF-710709.
The existence of a rapid annealing phase in the decay of space
charge induced in silicon dioxide by pulsed irradiation has been
demonstrated. This effect has been observed in MOS structures
prepared from both wet and dry thermal oxides and also in sevei
commercial N-channel MOSFET's. A simple model Involving th<
mal release of the trapped positive charge from a distribution oi
oxide trapping levels conveniently approximates the major featuj
_of short-term annealing, (auth)
•
i ^ /
©t'T
|"
USTEHMDTING THE EMERGE DIST.-JBUTI01T OP FULSEURADIATIOlT-i'
UÍDUCüír* CHAliGB III MOS STHUCTURBS PKOii B A U D /JilffiALIÍíG
1-lEASUHU.ilálíTS
M.Simnonsf H.L.Hughe s
IEEE Transactions NuoX.Sci. US-1£,Ho.6,282(1972)
A rapid annealing phase character!stir of spnee-charye
decay in SiOg following exposure to p*.<J.oed radiation has
been repox-tea. It is believed to be due to a thermal
activation process whereby positive charges trapped
in a continuous distribution of levels in the bandgap
are eeleased to the valence band and escaps without
retrapping. In the present measurements a 10 keV ion
beam irradiated the surface. Then annealing experiments
were made following exposure to a 3 nsoc electron
pulse•
PHOTOELECTHON CTJIttiEZiiS A2TD FIELDS Hi AIR-PILLSD CAVITIES l .
L.l).Sin£letary,3.Kelloher
IESK Transactions l'uclear S c i . HS-l_3,17O(l97l) N9&
A rsodol has been developed for the c a l c u l a t i o n of e l e c t r o n
transmission currents and p o t e n t i a l s generated in p a r t i a l l y
g a s - f i l l e d enclosures as a r e s u l t of photon i r r a d i a t i o n .
__
bD5~
j
'
tXiiiJl --• I- IL/li
l h U Li L.'.'JJ
JJi-ti^'.-iiiloiliJ
X :^JLJ.;\UÍ*Í.Ú11Í-.
ill
EGG Tech.Note 1IO.S336II !ÜCC 1183-2096,June- 1966
Report prr-senlinij r e s u l t s of a study of T.ajor e l e c t r i c a l
effect!? induced i n a polymeric i n s u l a t o r . Vhe l a t t e r i s
suppoec-d to be placed between iiietr.llic electrodes?, Rnâ
KSiix i r r a d i a t e d by high i n t e n s i t y ^amiTia f i e l d c-uid oonconiriiitantly subjected to the electron f i e l d produced by
the -" nterttctions of the gavajna-ray photons with t h e
electrodes anri with the d i e l e c t r i c n.T-.tcrit.1. S£fi;six
P r i n c i p a l e f f e c t s a r e ; Charactei i a a t i o n of primary
energy trír.nsí'er proceç? (yhoton-elc-.ctron or photon-nuclei
iCh.Hrf-i.cteriKHti.on of fre.condir.ry energy trt.riE.-fer (tntr.--;c ti<
electron? to atov.ic or r,ioleculfc.r sy: tc-mfj); Hip-cussi nri of
rneapureiiiEiitfi of «yfjtern and material propcrtic-s before,
during,and a f t e r i r r a d i a t i o n , w i t l i enphasit on r a d i a t i o n
» induced c o n d u c t i v i t y .
*
.
TR-«3T:.;PT HAMATTOI; ^«•F;:-GT3,Í";I^CTÍ?IOAL
••
<iuaTtsrly Proeresr, Heoort
•,V. A. Smi tV. , 0 . 3 . ,7al sh
EGG-llC'V-2014 .(iyrorton,Gf i vmorf;ha.ufien and G r i e r , S a n t a B
95)
iesoaroh on r-ndi o: nduoed conduotivity oh angus an
RADIATION STUDY ON MOS STRUCTURES
E."H.Snow, A. SvC3rove(Fairchi Id-Semiconductor-Labs
Mountain View,Cal.)
Scient.Rep.N2 l,Dec.l5,1965-May 15,1966
June 1966, AFCRL-66-449
Ionizaing radiation causes build-up of positive space
charge within the oxide of the structure. The location
of this charge and the kinetics of its formation and
annealing have been studied experimentally. A model is
proposed which relates the space charge to the defect
structure of the oxide.Photocurrents flowing in the
oxide following the X-ra irradiation and UV irradiation
have been used for constructing the detailed energy
band diagrams of the MOS structure.
r
•
EFFECTS OF IONIZING RADIATION ON OXIDIZED SILICON
SURFACES AND PLANAS D3VICSS
. snow/A; s ; Groo"s?e ,-Dv-JvFi tzgerald
—
Proc_._IESE ^55 ,1168-1135(1957)
Effects of high and! "low energy "electrons, X-ráys 7?.nd UV
are- cori3ideredvThe -fol-lowi-ng- effects- are -noted-:
{l.L,BujJLd-up of_pqsitive _charge_i_n_ the_ o:<i_de_
(2) Creation of fast surface s t a t e s at Oxide-Si
interface,"resuiting"—in "increased"-surface- recombina —
-_jtion_.velocity.. The. _ef f ects_.pf dose and _dose_ rate,bias
bias during irradiation, and of structural parameters
16074
(AISCIJ-322'1) UKNEIIATION OF ELECTRON CURRENTS BY fiAMMA-RAYS. Sovlta, J . A.; Truant, 1'. T. (Atomic
Energy of Canada Ltd., Chalk River (Ontario)). Nov. 19G8. D3p.
Dcp. CFSTI. CAN $1.50.
Theoretical studies are reported of the production of electrons
in a semi-Infinite plate by gamma-rays interacting by Compton
scattering and photoelectric absorption. Electron yields per incident photon were obtained as function of y-ray energies from
0.15 to 1.50 MeV, plate atomic numbers from 13 (aluminum) to 92
(uranium) and for plnte thicknesses up to 1.5 j / r i n ! . A limited
comparison was made with results obtained from É9Co GammaCell experiments. The analytical lnvesliRations are helpful in describing the behavior of coaxial self-powered detectors operating
in n similar y-ray flux. Extension of the analysis to electron generation in a radiation field con'.alnliij; neutrons and y-rays, as in
a reactor core, is recommended, (auth)
RESPONSE OP COBALT 1TEUTR0K FLUX DETECTORS
J.A.Sovka
AUCL-3368
(Report Appl.Math.Branch,Chalk River liuclear
L a b o r a t o r i e s , June 1Ç69
For monitoring t h e d e t e c t o r c u r r e n t due t o beta-decay of
s h o r t - l i v e d i s o t o p e s (Rh l o 4 ,42 sec and V52,3,76 m)
provides adequate response t i m e . For f a s t
flux transients
the prompt-response Co d e t e c t o r s were developed.However
neutron a c t i v a t i o n products c o n t r i b u t e t o background
signals th;-t increase with detector irradiation.
Paper gives mathematical study of response function.
ELECTRON BOMBARDMENT EFFECTS IN THIN DI3LECTBIC
LAYERS
W.E.Spear
P r o f . P h y s . S o e . B £8,993.(3.955)
Abstract. Dielectric layers of mica, Pyrcx, arsenic sulphide and antimony
sulphide, between 0-7 and 4/< thick, have been investigated under electron
ii.mibardment with electron energies up to SOkcv. Tho specimens carry evaporated Al electrodes, which arc practically transparent to tin- primary electrons.
I he results include transmission curves fur «he primaries; the range values arc in
j-rvctntnt with the Thomson-AVhidditigton law. With both electrodes at the
stnie potential a steady secondary current begins to flow to the bottom electrode
v.hen the bombarding electrons have penetrated about half the specimen. Hxperimental values of primary and secondary currents for specimens of different
xicl.isess an J dielectric lull on common curves v.h'.n plotted aaainst a suiiahlc
:nlependont variable. The secondary current is shown to depend on tho
abioi-lu-d energy. Results for mica with applied fields up to !(»'; Vcur ' across the
rviir.en are included. An interpr.-j.itio:i of the sicoutlarv cirivm curvei is
:iven in terms of the displacement of chaise carriers in the space-charge tield
iilliin the dielectric.
[
!
I
!
i
Í T MOBILITY TKOm/IQUES POii 'ÍHK STUDY OF ELBCTHICAL
Hl1 PKOPKRI'lrJU HI SOLIDS
J.iron~or,ví5tullinc üolidn 1,157(1969)
(Univ.Dundee,Scotland)
i'^i-or rcvico priaci);!^^ end o::pori;.:oir!;;:.l •fcoohi.iiquoíi involved
i n i..obilit;v ]:IC;.::;U:L'«Í.!.'JUÍS» l l ; . t o l c t ü u.rq í i f t o d -.dt.i cleoti-oloa
on op}'O oito cid©;> ÍIÜC. eru/r^o cau-riero aro {jcuurutoà ne;.r th o
top cleoti'otio D,y ti f;:.ut evolution pulse ( l i ^ i t or e l e c t r o n s ) .
A Gtcíuir or ]/u'i:.:cu Liprlicd fácld ciriaía os\o t.-^c oi" cerrioi"
tii.vcUo'ii tli- spücii:iüVi 0.11U the "fcr..iiíjit tii.:c i^ dotov.iinoi.- !.-;•
ciu,rc;c ini«tJ.V£.t:i.on or fj.'o:.; t;;u obwevvod ouriviit ti\.;::,icut.
'i'rav;pip.{j ir. úuilloi) ;.nu in doc.i, ti-j-pa ii; ulco uiccii.^ycd.
Viie AÍJTU i; o:.iu;i.- i.uil'ti;.<lo ti'ii^jiiiij; j.iii.. r o l c u a o , "lue ocuond
the c.pi)lical)iliti' oi1 t3i.Gnoti.od» lii.-..ÍCO cJ-ii\jo a
l_4,]To
—^
MHO.Shuck Generation in S-ZOO Beryllium Using a
Pulsed KU-rtron Beam.» V.Vf. SPKNCÊ, G. YÓNAS,"
Physirs international Co. and D.K. DEAN, Santlia Laboratories. - - Stress generated by electron energy deposition in S-200 beryllium has been measured with
quart?, gages and compared with calculated stress vs
well known and its high molt temperature
mixed phase effects in material response c
Stress h i t r i
l l t d
i
M
60 and 170 c a i / c m 6 . An additional major result has
been to demonstrate thu accuracy of existing electron
beam diagnostics in the determination of the eloctrun
energy deposition vs. depth profile.
i
I
j
\
j
j
•
I
2742?
(CONF-690540-, pp 524-31) A" SELF-CHARGING
ROENTGEN DOSIMETER WITH EFFICIENT UTILIZATION OF
PHOTO AND COMPTON EFFECTS. Speyer, Klaus (Allgemeine
Elektricitaets-Gesellscbait, AEG-Telefunken, Ulm (West Germany)). (In German).
A new typo pocket dosimeter was developed which consists of
the roentgen detection element, the electrometer, and the optical
system. The roentgen detection element consists of an outer
electrode of lead and an inner electrode of carbon. Because of
the difference in atomic number between lead and carbon, x radlation produces a voltage difference between the two electrodes
which is indicated by the electrometer. Advantages ol the new
dosimeter are stability ot zero point, maintenance oi a given
charge for long times, and no saturation effects at high dose
rates. (H.B.GJ
t
\
272C?
(AD-7334-16) KA1MAT1OS EFFECTS IN SILICON
AND OliKMANlUM. Final Ituport, February 2(i. lfiGÜ-Seplcmbcr IS, 1971, Srour,.!. H.; Ciirllc, C). L. Jr.; Olhmer, S.j Raurli,
It, IS. (Norlhrop Corporate Lnlis., Hawthorne, Calif.). Aug 1971.
Contract l)AAa3lJ-C9-C-00aí). 20Sp. (NCU-71-29-K; I1DL-6939-2). NT1S.
Jtcrumbination parameters arc determined for t0Co gammajrradiatod n-lype gcnnnnhmi (low resistivity) and n-lype silicon.
A study of transient photoconductivity decay in the presence of
traps for both irradiated and unirradi.'ited silicon and germanium
is presented. Measurements of the injection-level dependence of
minority-carrier lifetime for n- and ji-type silicon with neutron
doso as a pitriimctcr arc reported, liycful tvlationf-hips for r c combinuliiin studies am presented, including a nii'tlujd for dutermininK i'upturc-probability leinperatuix' dí-pondericos, Sliurttcrm unnciillnix stucMcs inchide an investigation of transient
recovery In p-type silicon followlnR pulsed l.-l-MeV electron
irradiation and an analytical treatment of the. effects of metaEtablc churn*.1 stales on Rhort-term annealing in p-type material.
Data iirc'fcenled indicato that licnl-lrralcd Cwchnilski-grown Aldoped silicon that undergoes an appreciable resistivity increase
during lic.'itint; at 450"C is ii|;iilficantly more resistant in both
neutron and i;amma irradiation than U-doptd nmtrrlal. A technique for performini; diffus/on-lcn^lh measurements usinj; a
scanning electron microscope is described, and results of preliminary radiation effects st'a'ieu on silicon employing this
method are presented, (aulh) iiNTIS)
6/7
.
I
;:orthvcf.it j.íib.) June. O S;--O
A ciu^litativo uoAcl role-tins ±ho nuclear xv.aic.Uon zncucc
current to cable r.:ateri.-a~,dimensions,and aose r a t e
ia d e v e l o p . I t prouicta poli.ritioa for each radiation
component. Currents up to Lo~d k/ond were mcauured an a
0.250 i n . OD coaxial cable placed in a THIGA r e a c t o r .
'UiCLBAll RAJ>IA;i'10:r liTJAJCUi) CUiiüSiíT ^ í ^ HiaLX-.TOlt KLSCraiCAL
J.L.Striu^or
v
DIRECT-CUSBMT CONDUCTIVITY OF POLYETHYLENE AT HIGH
FIELD-STSENOTRS
G.Stetter
1964 Annual Report,Conference on Electrical Insulation,
National Academy of Sciences,National Research Council,
Washington 2£f lS>65,page 21
Field, voltage, and temperature effects are investigated.
Keasureinenta of the discharge (short-circuit) currents
after polarization of thin (30 micron) samples with
fields between 1.8 and 7.3 x 10-> V/cm gave current reversals. They E*EE± could first be observed with about
5.9 x 105V/cra.aH!ixiiaBSEiBxvKrty At the highest voltage
the current inversion occurred shortly after short-circuiting,
subsequently the discharge current had the same shape but
opposite polarity as it would have normally, i.e. it was
in the same direction as the charging current. Observations
were made with mercury electrodes.
h2Ô
172
THE IlJiaUiJtfCü OF GAi'JiA IRRADIATION ON THE ELECTRICAL CONDUCTIVITY OP CLASSIC
T. Sugiura,K ,l! u rakaini, H .Tun álea
Yogyo Kyokui Shi JO,23(1962)
Gamma r a d i a t i o n e f f e c t s and a p p l i c a t i o n of i r r a d i a t e d g l a s s
to semi conductive g l a s s or r a d i a t i o n dosimeters are d i s cussed*
A IIÜTJ1O3) FOR THIS HOui'lliU LJiiAíililíüLiJiWT OF liliiLBCTRIC
KIOTOüOlÜXJOTIVITY
U.K.Sullivan, R.L.ISving
(Sandia Labs.)
IBiSB Transactions tfucl.Soi. 1T3-18,NO6,310(1971)
Peak conductivityxsxdof Teflon s.-nd Il-film have/ "been measured during intense ionisatio-.jradiation b u r s t (about 40
ns)(~6x!0-1--'- R / S ) « I t i s conoluded t h a t l)coramon c a p a c i t o r
d i e l e c t r i c s should be examined to determine vhcther they
can be driven into the bimolecular recombination region
2) tho apparent dimappearunce of p o l a r i z a t i o n effects at
high doocis siiould be examined 3) the technique could bo
used viith tho older i u t o c r a l of oonductivity neasurcucnt
to obtain detailed conductivity data over the e n t i r e
history of i r r a d i a t i o n and decay.iieoulto are i t 6.3x10*- rad/f
Material
Kp(r£id~* )
ò
Teflon
1.1x10-5
0.953
ll-film
g.lóxicr 6
0.98?
AJ? /
62?
A delayed comx:onent vrith a deca;-; time constant of 15 no iras
observed.
ELECTUOCOjiDUCl'IV.TTy FKA'i'URSS OP ALKALI SILICAl'B CLASSES III
iilGH M.yO'i'iilC FIELDS 'Mil TO GJd.l'A líüíAJlATIOlí
A.l.Syriak
Icvestiya Vysnhil±. Uchobnj'l± Zavedenii,FiaiIia, "0.4,31(1966)
I
i
)
I
I
I
!
!
CHARGE EFFECTS IN DIELECTRIC FILMS ON SILICON
\
J.R.Szedon (V/estinghouse Res.Lab.,Pittsburgh,Pa.)
Thin Film Dielectrics,Conference,Montreal,Canada,
7-11 October 1968 (New York,Electrochem.Soc.1969,
P.84)
Paper reviews ion migration,injection trapping,
electron irradiation effects in materials curren' y
used in Si planar technology.The use of capacita: jevoltage analysis of metal-insulator-seniconductor
structures is discussed.The application of these
analytical methods to study of reactively sputtered
SÍO2 and TáO on Si is mentioned.Examples of how to
control dielectric charge behavior are given.
*
H
X-RAY FLA'OII TUBS POii Tllfí SlWtt' Oi1 PAST I'HOCJISSBS
Vi. Schaars
RADIATIOlT-IlflWCED CA.BLS CURRENTS. PART I .
Palo H. SohaUaorn, Edward S. Conrad, and Elan» I . Ellsworth
(Harry Diamond Labs.» Washington, B*C.) Deo.30, 1953. 34 p .
<TB-X167)
I RG-58/u, RO-50- B/U, and RG-6s/u coaxial cables wore exposed
to puliseâ radiation in tho Diamond Ordnanco- Radiation F a c i l i t y
(DORP) r e a c t o r . Conduot&noo and replacement currents varo
measured with tv?o difi'oJfsnt cablo configurations — one v?ith the
irradiated portion looped into a hairpin chaps, tbo other v?ith
the irradiated end of the cable f&stened to a terffiinul lioax'd and
tha entire assembly osyooad to the radiationc Data were- olstain&cl as a function of distasioe from the radiation eourc« in
tho rsaotor and in a noutron-froo Co-60 gasraiia ray onvironraent.
Tha tost rosulte suggest that the p o l a r i t y of tho replacement
current depancla on the energy and type of incident r a d i a t i o n .
I t was d e t r a i n e d that oabl&a can bo ueod to porforni sxpex-imonto
in DORP without introduoing tnoro than 0.8/sa replao&i&ent current
a t tho peak of tho reactor pulee.
PiiEDICTJiW Al'
PiiEDICTJiW
Al.'D
D MíilAÜUiiSü
MíilAÜUiiSü
KLEC'i'HOJr uPEC'i'RA.
DliíTJÍ
DliíTJÍ Doaa
Doaa p/.Ol-'II
p/Ol'II Kb
Kb .'""OK
OK 1ULS3X
1ULS3X»
D.ii. Sohallhorn,L. D.Buxton
IBE3 Tr£.na.i:ucl.£5ci. !!S-l_6,
-Harry Diui.io.-d Labs.líasiiinatüii JJ.C.Ü04'J>Ú
Bxperir.outr.lly menaurcd profile o vero compared with thoorotipfflifÍjl-OB .2;casuro!..Qnts wore carried ou in following way»
Materials wcro exposed to pulled, electron betja fron fli-.sh
X-.ray unit.Tne r.iatorials rear surface Motion inâuced l-y
the exposure was aea&ured vriâli a i s e r iiiterferometor.Tho neasured responses vere converted to velocity hitstoi'ies vhci
which can be relatou to depth dose profiles .1-line materials
with Z between 13 and 79 were stxidied.
024203 Scliarf, K ; Mohr, R.K. Tcmpcrnlure dependence
of photocutrcnb produced by % aud gamin» ra)^
in silicon radiation delcclors. J. Res. Nal Bur. Stand.
(1971). v. 75A(6) p. 579-589.
electric currents; gamma radiation; radiation effects; si
semiconductor detectors; temperature dependence- x
radiation.
BULK SPACE CHARGE MW TRANSIENT PHOTOCOIiiJlJOTlVITY
IN AiviOlU'HOUS ÜIJLMUUM
1.1 .l';.Scharfe,M.D.Tabak (Xerox Co.,Rochester,N.Y.)
J.Appl.Phys. 40,3230(1969)
The drift of a small photoinjected sheet of
free carriers can \>e used as a probe of space charge
i'iRidxxRKx and field distribution in the bulk of '
amorphous Se.
yULSK» EUCLUATi RADIATION EFFECTS OIT ELECTRONIC PARTS AND
MATERIALS. (SPRF 1J0. l ) . W. Sohloneer, C.P. Lascaro, and J.Koy
(Array Jítootronieg Research and Development Lab., Port LJonnsoutlif
1T.J.) Sopt. 1962. 45p. (AD-4JS556)
The results of a rooont series of experiments conducted on
electronic parto at the Satidi.a Pulsocl Roactor Paeility &re diecuoseá. Cablos, resiatoro, ancí ferrite coras were included in
tho progiam. Four cables including R0-62A/U, B G - 5 ° B / Ü , Bfr-8l/ü, b "2 0
anâ a -i-wiBted pail* lino cord v/ero expoeed in varioua goometriGOj
ciTOuit», ana applied voltages. Expo sect also v/ers lOO-nhra,
1—Irohm, lO-knhn, and 100-kora carbon film i-esistora, a 100-ohm
v.'ire wound roniotor, ao well as manganefi-fsinc and njckel—sine
ferrite coros. Peck induced currents observed in cables vreros
+3000 to - 2650 rnlemniDp in looped IÍG-8j/üs 46OO to -2500 microamp in looped BG-62A/U, +300 to -380 raicroamp in looped RG-59B/U,
+400 to - 16Í5O mioroninp in looped t?/isted pair, +80 to -Ç0 microruiip in straight potted R0-62A/U, and +800 to -500 microaiop in
straight unpotted B 0 - 6 2 A / U cablo. Low-value resistors appeared
/quito stable, but reeifitors £,Te:iter than 10 kohin oh owe d
' a spurious and inconsistent bohavior,attributed largely
to lc:;.d cable effects. The measurements on c;Cblce end
resistors eeera to boar out the fact that reliable data cannot
yet be obtained, for many exposed coiaponent parts becuuse of
unpredictable behswior of tho ca-bleo used for signal
transuiaaion.
\
j
PÜLSÜ-D inJCLDAR RADIATION IHT5ÜCED TRANSIENTS III ELECTRICAL
OABLKS
'
Vf.Schlosser,J.Bewberg,J.A.Key
.
AD-623.016
.July 1964
(USA Army Electronics Labs.,Port Konmouth)
Observed currents contained 3 componentes a replacement curre
current, a conduction current, a charging current. After
repetitive exposure the first component predominates.
The charging cureent is attributed to introduction of
charges ss£ in an initial exposure and to redistribution
of them in an exposure accompanying a change of applied
voltage. The transients were produced by irradiation in
a TRIGA pulsed reactor.
r
\
, .
•
I
;
j
175
36577
THKOltY AND APPLICATION OF FEUUOKLtiCTKlC
KAD1AT1OM DK'ir.CTOItS, fííihloaner, P. A.j Miller, P. W.;
GJowor, D, D, (Ohio Rluto Univ., Columbus), Int. J. No tide, struct.
Test; 2: 19-29 (Jun 1970).
A theory whfcli pxpluinH ílic detail» of tbc radiation-Induced
charge release phenomenon of ferroelectric detectors has been
developed, Thiti tliomvliciil ctevctopmttnf provides addition.'tl inflight into the operation and npplication o[ fcrocloctrir devices
In lhe broad Hold c»r radiation measurement. When placed in a
radiation environment llic detector responds by virtue of fts
pyroelectric properties. In this process the absorbed energy
causes :i slij;lu chango in temperature which rosoit*! in a change
in the internal polarization. The theory which has been developed
predicts that the polarization chanfje causes a perturbation of
equilibrium electric fields and the appearance of free charge at
the electrodea. The quantity of free charge which is released is
proportional to the energy which is absorbed from the radiation,
Ferroelectric detectors respond to ionizing radiation and have
found applications in the areas of flash x-ray dosimetry and
spectroscopy, l;if»er calibration systems, linear accelerator
calibration, plasma diagnostics and pulsed reactor dosimctry.
The detector's rugged nos s, email size, very fast time response
and zero-bias operating characteristics make it ideal for the
measurement of intense, sources of pulsed radiation. <;uitM
bit
13027
ELKCTRICAL CONDUCTIVITY OF 2-PENTENE IRRADIATED AT 77°K DURING WAHMING TO 12&°K. bt.tcliowicz,
W.i Owczarci'.yk, A. (lnst. of Nuclear Research, Warsaw).
Radioohom. Kudloiiml. Lett.; 5: 305-12(31 Deo 1970).
The electric conductivity tcchniquo was adapled to the dimly of
the transient cítarfíuri spades appearing in the range of 77 to
1251Í in (.iissy (U-pentene) followini; Its y-irradiation. Three
peaks coi-refponding to differo.nl specief were observed, (auth)
FOR CALIBRATION OF )IIGH - I ^ Í T J
FLASH X--11AY MACHINES
J.Stevens,H.IÍ.Eeoi-B,I.a.Cobtreras
Rep.EGG 1103-223O,Junie 1970 Ü-479-H
Describes monitoring method» using a Compton detector
conaioting of a 3-cloinent (Fb-C-Cu) emitter ,a biased
grid (for supproaion of unwanted electrons),raountud in
vacuum chamber» Compton spectrometer us used for energy
analysis.
16216
(N-08-33277) INVESTIGATION OF ELECTRONRADIATION-INDUCKD D1KI.KCTIUC HHRAKDOWNS IN A TVP1CAI. CAPACITOU METEOKOin DliTHCTOU SYSTEM. Stortl,
George M.; linmbo, George E.; Hendricks, Herbert D.; Ballard,
Thomas B. (National Aeronautics and Space Administration,
Langlcy Station, Va. Langley liosearch Center). Sept. 1968.
29p. (NASA-TN-D-4738). CFSTI.
The effects of election radiation on capacitor-type detector
systems similar to those used on the PcgnmiE satellite were investigatcd. Each system thut was tested consisted of a polyurethiuio foam panel containing two capacltor-typc-meleoroid dotectors, scvci'at meters of polyethylene turcphüialatç ínsutnted
eleclvlcitl Iciidu, and other itoins sueh a& rubber shock mounts
and polyethylene terephthalate adhesive tape. Three different
target thicknesses for the mi'leoroid cL-toctors were tested, 40,
200, and 400 microns. The incident Mnctic energy of electrons
used in the tests ranged from 30 k<?V to 1000 kcV, and the temperature of the detector systems watt maintained at cither
197 or 2!)7"K. It was found that radlotlon-iiKlnccd dielectric
breakdowns were produced In the systems and thut &ome of these
signals were indicated as metcorold penetrations. It was determined that the primary source of the breakdowns and, hence, the
penetration Indications was the polyethylene tcrephthalate insulated
wire. The number of breakdowns and penetration indications obtained for a fluence of 5 x 1013 e/cm2 was found to be dependent on
the incident kinetic energy of the electrons and the system ternperature; that is. more breakdowns and penetration indications
occurred at the lower temperature (197°K) and the lower energies
(30 to 100 keV). Tests were performed with different modifications made to the signal processing circuits. Several of these
modifications resulted in a significant reduction or the total
elimination of the radiation-induced penetration indications.
Finally, it was found that those systems containing 200 and 400
micron detectors with 200- and 400-mieron-thfck targets suffered severe decreases in resistance in the capacitor-type detectors. (autM (STAR)
34891
RESPONSE OF SELF-POWERED GAMMA DETECTORS. Strindehag, Ove (Aküebolaget Atomenergi, Sludsvik,
Sweden). Atomkernenergie; J7: No. 4, 267-70(Jul 1971).
Experimental results from an investigation of self-powered
gamma detectors with emitters of lead, zirconium, Inconel 000,
magnesium, and graphite are presented. The detectors are intended primarily for in-core applications in power reactors,
and the detector design is the same as for a type of neutron sensitive eclf-powerod detector previously utilized for In-corc measurements. Detector sensitivities measured both in a eeCo gamma
coll and In a test reactor arc given. For detectors with lead
emitter the moojured sensitivity in the gamma cell Is 8 • 1 0 ' "
A/Rh"1, and for detectors with magnesium emitter 1,2 • IO"'C
A/Mi"1, (auth)
•
I
*
'
I
I
...
'•
.
•••
v
-
i*}^
O *>O
f""
f
,
•
:
',
1
i
\
v
"
I "2 /
O<5>O
1ÍUCLEAP. RADIATION IlíliUCED CURKEIJÍS IN COAXIAL SIGKAL
CABLES.
J.L.btringer. R.R.Bourassa
BHWL — 7/]9 (1968) (liop.iiattelle-Korthwest, Richland,
WabiiJngton,Pacific líortvcot Lab.)
The folloning problems are discussed: (a) Gamraa ray sources
with isotropic distribution ousiue coarial cable shield,
(b)same, with cable shield((c) Electron sources distributed
within tJie cable shield. Parameters ares radiation flua:
and energy distribution J physical and chemical cable
characteristic». A circuit diagram is considered vdth a
true internal current source, noting that the current
is independent of the voltage which is proportional to the
intornal resistance. It ie shown that by adjustment of
cable parameters the current can be made positive or negative.
Pair production, while producing increased noise, gives
aero net current. But annihilation of positrons ocurring
internally can give a courront sotirce: thic is exactly the
internal som'ce problem. Since the distribution is
essentially isotropic, only the geometrical factors rei.:ain.
'i'hua the current might be positive or negative .Finally
, neutron interactions are considered.
•
\
Í
4520
(BNWL-114S) NUCLEAR RADIATION INDUCED CUR-
KKNT AN» IKSULM'Oll ELECTRICAL CONDUCTIVITY MEASUREMENT TECHNIQUES APPLIED TO COAXIAL CABLES.
Stringer, J. L. (Battelle-Norlhwest, Rlchland, Wash. Pacific
Northwest Lab.). Oct 1909. Contract AT(45-l)-1830. 27p.
Dep. CrSTl.
The techniques used In measuring the nuclear radiation induced
current and the combined temperature anil radiation induced eleçtrical conductivity on metal oxide (MgO) insulated conxlal cable»?
arc described. An analyHin is prosenltd for each technique de- j
scribed and several problems encountered In applying the tech- j
niques nre discussed. Data arc presented for the induced elcctrical conductivity a» a function of temperature to 700*0 and radiation
dose rate to 9 x lo 10 R/hr. (auth)
8894
DIPOLAR COMPLEXES IN KC1 RESULTING FROM
1.5-MeV-ELECTRON BOMBARDMENT. Stoit, J. P.; Crawford,
J. H. Jr. (Univ. of North Carolina, Chapel Hill). Phys. Rev.,
Bj 6: No. 12, 4660-7(15 Dec 1972).
The dielectric relaxation behavior of KC1 crystals after exposure to 1.5-MeV electrons was studied by means of the ionicthormocurrent (ITC) method. At least four 1TC relaxation peaks
at 125, 145, 160, and 195°K are observed over the range from 80
to 200°K after irradiation at 260°K. The irradiation temperature
is found to have a strong influence on both the form of the ITC
spectrum and the total amount of polarization. The production of
dipolar defects, assumed to be responsible for the relaxation, is
highest for irradiations in the range 200 to 260°K and it is rather
small for exposures at 160 and 300TÍ. Once produced, the dipolar
defects are relatively stable but they can be nearly completely
removed by a 400°K anneal. The effect seems to be intrinsic In
nature since the total polarization build» up linearly with exposure
after the F center has substantially saturated and since it is e s sentially the same for high-purity crystals from several ingots.
Assuming that unit dipoles are responsible for the ITC spectrum,
the initial rate of formation i3 0.05 times the initial rpt e of F center production. Sinco it is difficult to conceive that such a
variety of stable dipoles can be constructed from anlon Frenkel
detects, it is concluded that defects on the cation sublattieo also
result from the irradiation. It is shown that the yield of dipoles
is at lenst an order of magnitude highor than can be expected to
result from direct displacements induced by electron-lor. collisions. The same types of defects may bo precursors for the crystallogrnphlc voids and dislocation loops observed by electron
microscopy in heavily irradiated alkali halides. (auth) -
/
jfl
O OO
(
I
I
L •?,£
" ' 7
_J
a j>üi:E;;ü:á::o]j
OF HOL»; ;HUA::ÜÍV1Ú[
in
Wiys.Rev. B 2,2104(1970)
~
\
\
Annual Report of the Radiation Center
of Osaka Prefecture, Vol. ÍQ (19G9) . £ > . £ ' /
Snkai, Osaka
Range Distribution of 4- to 24-MeV Electrons
i.
Tatsuo TABATA, Rinsuke ITO, Shigeru OK ABE and Yoshiaki FUJITA*
!
(Received December 25, 1069)
•
,'
\
\ ,
Experimental data are presented of the range distribution of electrons in the absorbers of
Be, AI, Cu, AR, and Au. The measurement has been made with a thin charge ci/llector inserted
in the absorber, and the energies of the incident electrons investigated arc 4.09, 7.79, 11.5, H.9
and 23.5 MeV. The distributions observed have been fitted with an empirical equation in which
an expression for the transmission curve given by Mar is utilized in a slightly modified form.
The most probable range A',,,, the practical range Rp, the mean projected range R, the \-?ó
range Ru and the range straggling parameter AR have been determined from the distributions.
Two types of empirical equation for expressing the ratios of the range parameters to the
theoretical mean range have been compared, and the one originally proposed by Harder and
Poschet has been found to give a better fit for all the range parameters considere
red.
5590
EMPIRICAL EQUATIONS FOR THE PROJECTEDRANGE STRAGGLING OF 4- TO 24-MeV ELECTRONS. Tabatu,
Tatauo; lto, liinsuke; OltRbe, Shli;oru; Fujita, Yochlakl. (Kyoto
Univ.). Annu. Hop, Kadlat. Center Osaka Protect.; 11s 07-70
(1970).
An umpirlc.il equation for lhe proJeeted-rango-atragiilinB (PIUS)
distribution of 4- to 24-MeV electrons lias been developed by
utilizing the expression of Ebort et al. for the transmission cuive
In a modified form. The curves given by the equation are compared with the cliarge-deposition distributions observed and those
calculated with the Monte Carlo method by Berber and Seltzer,
because these distributions can be considered to represent the
PKS distributions to a good approximation. The comparison shows
that the empirical equation i-eproduoes the actual PUS distribution
well, except for slight discrepancies in the cases of lonr-Z absorbers. Empirical relations for the PRS parameter 4K are also
described, (auth)
;
:
I
,
L 1,1
<? 1 i,
\
I
!
{
Í
j
j
I
i
{
I
racnt
5591
SEMI-EMPIRICAL EQUATION FOR THE MEAN
PROJECTED RANGE OF ELECTRONS. Tabata, Tatsuo; lto,
Rinsuke; Okabe, Shigeru. Annu. Rep. Kadiat. Center Osaka
Prefect.; 11: 71-4(1970).
The semi-empirical equation between the mean projected range
K and the mean range L of electrons developed by one of the
present authors was modified. The new relation is of the form
H = L(1 + LA')" 1 , where A0 = Ag/f(Z, C|j); Aj is the transport mean
free path of the incident electrons, and £0 is the incident kjietic
energy of the electrons In units of the re3t energy of the electron.
Assuming a \lnear function of <o for f(Z,Co), satisfactory agreewith experimental and Monte Carlo results was obtained for
energies from 2 to 24 MoV. However, another modification previously reported shows a better agreement with the Monte Carlo
results down to 0.25 MeV. Kquatiops that express the moan range
as a function of en< rgy In the region from 10 koV to 1 GoV arc
given, (aulh)
CliAKGE DISTIíIOTPION PHOiTJCED BY 4.-TO 24-HeV ELKCKÍOIIS
II!" ELSIEIÍTAL LiATIililALS
T. T a b a t a , l i . I t o , S • Olcab e
Phys.Rev.33_3_,
570-581 (1971) 1 Feb.1971)
Osaka Prefecture,Sakai,Japan)
Charge deposition profiles of monoenergetic
electrons normally incident on thick abrof3erbers were measured
using the Gross-Wright method, modified in so far as the charge
0- the catcher and that of the rest absorber was measured, iiesults aro compared with the Berger-Seltzer theory.-Considering
the absorber syate...,suppose thfct the region from x-ôx/2 to
x+ôx/2 serves as an insulated charge collector. One measures
the charges oq.(y.) and Q(x) duo to net absorption of electrons
in catcher and in. the rest of the absorber.The net charge
hbnorbed by whole absorber is given by their suinThe ratio
y(x)dx of the not charge deposited in a layer of thickness dx
at depth x, to the total charge of electrons absorbed in the
whole absorbe r is determined from
y(x)cbc =ôa(x^bc/Z"ôÇL(x)+^(^)_7ôx-Tlie
ratio
°$ V o M à *
of
the
bcü.ie not charge in dx to the total charge of -Uie incident
electrons is given by y o (x)dx=(l-n)y(x)dx vihoi'o n is the
bacJLfjcattering coefficient at saturr.tion of t3ie incident
electrons for the matcirial coUoidored. It cccir.3 that ti^c
cai.'.e nctnod iras used by Ví.AlexatidorjJi.li.BrynJolfÍ;:ÍOII,COO'; er
U.U.Ai'r.iy Katie Lab. .''i'echnical liep. 3To. Fd-2(Íj6/]) ,unpiibí:
E>"I.11UVO1.A'Í3:) lilTü PROJUCTHD 1U::G}J3 Ü 4 t o 24 1 eV
3jJiCTRo:rs in ELTJIIKTTAL !-ATUKTALS
T.'i'abata5K.Ito,S.OkabejY.Pujita
J.Appl.Phy D . 42,3361(1971)
3i:ctró.r.olated and p r o j e c t e d range vuliies were
detor;.iined from chcuvje d&ijosition i i r o f i l o s . ! OLiwurenot
e r e r e p o r t e d f o r 33o Al Cu Ag An.
OBTAINING A SYSTEM OF DOSIMETRY
S.I.Taimuty
Stanford Res. Inst.,Menlo Park,Cal. S-559,Progress Rpt.
*®,23 Nov.1957-27 Jan.1958.,DA-l'9-129-Qíá-766
ASTIAjAD 205351
A REVI3?,y OF DOSIMETRY FIELD
S.I.Tairauty
Stanford Res,Inst.,Menlo Park,Cal. , S - 6 l l , S e p t . 1 0 , 1 9 6 2
DDC^AD 296591
Revitft/and c r i t i c a l evaluation of l i t e r a t u r e on h i g h - l e v e l
gamma and e l e c t r o n beam
radiation
dosimetry,published
since 1958.
/>'/i™
X-Ray INDUCED BULK PHOTOVOI.T/. IC EFFECT IN INSULATORS
S.I.Tainuty.L.Feinateir^S.D.Softky
Science M£,173(l9f>4)
Vhon cm inaulator eandsichcd between mota.i.s of diG~
sir.iilar vrork functions is irradiated by X-rays, a voltage
rolated to the contact potential of the totals ic found.
This "'bulk p)iotovoiUi:i.o"cffoct,i.roviouül;' eLovn onlj \dtli
UV and visible li^htjiias no'..' "been dei.ionotra.tcd for c. varia
oty of l-ill-i combinations, 'i'he voli^ce, for insulator
layers of 10~^ to 1O~2 cm, its of the order of up to 2 Y. '
e n H'Oiiiocc'T'i.'v;-.iic:r o:-
18422
THEFtMALLY STIMULATED CURRENTS FKOM
GAMMA-IRRADIATE» ORGANIC POLYMERS: POLY(METHVL
METIIACHYLATE). Tatnsky, Morgan Jerome. Lawreno.-,
Kan.; Univ. ot Kansas (1970). 231p. University Microfilms
Order No. 70-20,410.
Thesis.
The phenomenon of thermally atitnulatcd currents ÍTSC) from
y irrndiation was studied for the following polymers, especially
polytmcthylmethacrylale (I'M MA); isotactic 1'MMA, syndiotactic
PMMA, commercial PMMA, polyethylene, polypropylene, polystyreno, polytetrafluoroethylene, polyvínylchloríde, and caronuba
wax. Disk shaped samples, a few cm in diameter and about one
cm thick, were omnidirectionally Irradiate 1 ! in a '"Co sources to
doses of 1 Mrad at 31 'C. The TSC wan measured by heating the
samples at controlled linear rates, l.S to 6.3'C/min, with a vibrating reed electrometer in the same circuit with the sample.
The major conclusions ol the present study apply to PMMA specifically but are not restricted to only this polymer: (1) The
Atp p
-ELECa'HICAL CO1IDUCTIO1T OP HIGH POLYMERS
T.Tanaka,Y.Inuishi
Technol.Hop.Osaka Univ.(Japan) 12_, 127(1967)
Substances like polyethylene and polycarbonates were
investigated from the standpoint of electronic
teuisport
theory. Carrier trap centers are found to be of importance
±E
by measurement of low and high-field
conductivity and breakdown.
conductivity,photo-
, _.
hot
ELECTÍ ;o::ic TJÍ/JTSPOIÜ' HI
Vi.Tantraporn
8?o avo'id b'arria:;1 lin.i i.ati on at injecting electro do arid the
effect of iniiCirf'Gcfciony in the ir.c:"ülator,a loi; cn3rtj;(*<30cV)
(scanned, s t a t i c or pulrcod, electron bean wao 'used to wtudy
bulk properties.v'he vcO ta&e drop acroas-the insulator v;:m deterraincd by aouparin-; current-voltr.iv: character!abics of the
collector before and after deposition of tho inoulatiri;.; film,
i'he hot eloct'i-on ;J.i.';or,v'tj on coefficient «as measured as a
function of tiio kino tá. o cu^r^-y and effeotivo ir.ii./ber of their.E
li::od electrons:;. PoJ.^i.iCiidi-Aíd Silicon o i l fDlr.a of C<7OA° t)iic3i>
noa» v;ero iiaod. Under d.o. an abyorvtion coefficient of 4xlO~:
A° and an effective nobility of lo-^-l cn2/Y ooc were fV'V.nd.,
both boins nearD.y independont of tho electron ouor^y.yhe
pulcea iucaaui«c::.cnts .iindcatod uor.euhat larger aboorption.
In the i-aiior t>o aTjsorption lenj.th xiv dofinod a a the upper
lii.iit of the ncan free path of the electrons.j'or ver;/ t a n
f i l r a tho properties so determined are characteristic for
"hot'••jlaotrono because tho electrons aro injected with a
l i n o t i c enei\'jy which in hijh vrhon i/.oasurou í'ro::i botton
oondi.iction band;compared to oçLuilibriuia ener,^ in the bull:
o£ tho natcricil • •
'
.
JEFFECTS OP IONIZING RADIATION ON INORGANIC AND ORGANIC
STRUCTURES.
Taubmon, A . D . , Yanova, L.P.
]n DoUlvie loniziruyushchikh Izluchenii na Neorganicheskie i Organichesl-.ie Sistemy
Moscow, Akad. Nauk SSSR, 1958. p. 307, 314.
'
I
Reports on electron irradiation of plastics end breakdown effects. The "growing fate"
of the discharge patter» v/as measured for a constant irradiation dose. It was found to bo
much slower in polystyrene than in polymelhacrylafes or in Kel-F. For a given polymer
it ropidly decreases with increasing temperature of irradiation. No discharge pattern
was observed when the irradiation wos carried out above the glass transition tempsroture
iOf the polymer.
1
'
f
1
•
J TKEHMALLY STIMULATED CONDUCTIVITY OF IKEADIATED KBr \
A.Taylor
I -- •
physica status solidi 37,401(1970)
1288S
THERMALLY STIMULATED CONDUCTIVITY OF
\ /
TR
y
V
IRRADIATED KBr. Taylor,
A. (Cornell Univ., Ithaca, N. Y.).
Phys.
Status
Solldii
37:
401-12(1
Jan
1970).
5
Ph
S
S
3
2 1J 9
The thermally stimulated conductivity of KBr crystals irradi!•
ated at 10°K with monopnergetic (500-kcV) neutrons and y rays
\
was studied over the temperature range 10 10 300°K. The peak
spectrum below 70°K was associated with the annihilation of lattice defects created by the irradiation, while the higher-temperature peaks were interpreted as due to the depopulation of impurity
traps. The annealing kinetics of the low-temperature peak were
consistent with defect annihilation processes controlled by the
migration of the Br~ interstltials. Neutron bombardment enhanced
significantly the low-temperature peaks above the level established
by bnclíground v rays, (auth)
/ t?.
C»7
.
,
:
i
VACU'Ji: IOITIÜATICIT C H Á K H E R
L.5.Tc;vloiBrit.J.Rudiol. 2±,C'l(1951)
A vacuum dositt'jtry system.The charge collected depends
strongly on -tho.feowotry of the electrodes. Any c,v.in
or loss of charge of the central electrode depends on
electron transfer between the wallo and the central electrode,
not on Q&O ionization.
EFFECTS 01' TRANSIENT NUCLEAR KADIATIOH Oil TRANSDUCERS
ERS 11
Al.ri> ELECTRICAL CABLES
F.B.Terry
lti0-16<A4
(Idaho Operations Office,Idaho
E Gives
„.. - j. ,. swpirical results on cable
laeaBurciiients under different conditions and fluxos
and for different types of cables. tioth currents
and voltüü es al>'2 éJivên. The radiation from SPSHT
(puleed reactor) is ^lcad where both gijriLias andr
neutrons arc present. Dose rate was up to cJxl0 fi/sec,
pulses syiümetrical,duration 13 nsec. Currents between
-82 and + 37 micro-A were found, due to Compton
sccttering and ion pair formation. A bibliography
of other work on induced currents in cables is attached.
i
injCLUAK KADIATIOIÍ IÜ-VECT3 02? TXAlíàiAlCEií UÍ3V1CE3
AI;D ELriOTHICAL CAULES
P.üíTeriy,li.L.Kindred, S«D.Anderson
IDO-17103
(1965)
«•-
DOSE MTU A1-ÍD SPECTRAL 3IEASURS.J31TTS PHOL PU1.S3I» X-RAY
GEirBrijiTOHS
E . T o c h i l i n , I i . Goldstein
Health Phj-s. 12,705(1566)
•
l o
Measurements a r e nade up t o dose r a t e s of 10
R/sec,with
a t o t a l dose of about 10^ R (corresponding t o pulse cizey
of 10-8 t o 10-7 sec .
"
\
8275
EFFECT OF y IRRADIATION ON DIELECTRIC CONSTANTS OF KH2PO,. Tokumaru, Yukuya; Abe, Ryuji (Nagoya
Univ., Japan). Jap. J. Appl. Phys.; 9: 1546-9(Dec 1970).
The effects of y radiation on the dielectric constant of KH2PO4
monocrystals at 10 to 150"K were investigated. Both the real and
imaginary parts of the complex dielectric constant decreased with
increasing dosage, until they nearly saturated at about 3 x 10s rad.
Recovery was observed on heating to about 175°K. (M.C.G.)
60/
0 ( s ) S - 1 0 DILLj-ICmc (XWPTOK JK-K.CTOii ]>:.?.,] Oi'L'.VilT?
R!vPüR-T
E.L.Tolmau (ijd^csrtonjGGrpierahauson and G r i c v , ü n n t a Burbnva Ca
Cal.,USA)
"
" '
EGG-1183--H74
D e s c r i b e s s p h e r i c a l Compton d e t e c t o r . I t i s s i m i l a r i n c o n s t r u c t i o n t o s p h e r i c a l Coinpton d i o d e s p r e v i o u s l y i n use,fc
except t h a t t h o space between t h e o u t e r electi-ode and t h e
(ceriter)collector electrode in f i l l e d with a d i e l e c t r i c
(polybutcnie oil,grade 32 X) .Tha,cutfli(l« steel oloctvode
has an outfiide diainstor of % fW ^
,inr,jdt; 7",oil thicknoos
13/4",E:£ Sorifrltivity ic 10-lo A per- n/aec,ifiio:ii;,uin
current capacity about 100 Á into $$ 500 Ohm ay ateei,
ciivnnl trnnc.it time 26,88 noec» 3yüfc':in i s son :>i tive to
gammas and to neutrons due to recoil protonn from the oil A
THE PEMETR/iTlOJí <5F
U.G.'Pomlin
/ /,
bo]
Pror..Phyd.Soc,(London) 0_9,Pi-svt 4 } BO^Q^Co)
/
*
I
I
21031 X-RAY ANI1UV UOSIMKTRY BY NON-I.VMINi;SCi;ST
SOMD-STA'IK MliTIIOUS. 'I'oole, James Michael. University Park, Pa, j Pennsylvania SU'te t'niv. (1969). 79p.
Thegls.
>.
A doslinctrlc procedure is described which mal:cs use of the
pyioclecfric properties of a material. Finale crystals of ZnS
(wurttilc) anil tourmaline (green variety) are used as dosimeters
for ultraviolet and x-ray radiation, respectively. The crystals arc
in the form of platelets with the large area surface normal to the
polarisation axis. Polarization is produced «hen the crystal temporalure is increased linearly by heating an oi! bath in v/hich th«
crystal has been immersed, or by means of a specially designed
teat chamber. The measured polarization Í3 governed by the pyroclectrlc coefficient as «ell as thn internal resistance of the specimen. The latter Is diminished, in the course of heating, by d e c trons released from traps previously filled by the incoming
radiation. The chavior of the system Is analyzed In terms of an
equivalent circuit which regards the material as a constant current generator. Comparisons with thcrmoluminescenco and current glow processes are described. ZnS is found to be an extremely sensitive dosimeter for u.v., but has a very limited range
and ™*'v"r poor storage capabilities. Tourmaline on the çthur_^
hand, as an x-ray dosimeter, is quite insensitive but has extended
range and long term storage capabilities. Both materials are
similar in their behavior as dosimeters. (Diss. Abstr.)
•
I
]
»
'
/ / n
VO e.
F
'
|
<
» ' '
\
'
1
THEHÍ-íO-VOLTAIC HADIATIC1I BCSIiiHTRY
•
\
J li.Toole.H.K.Henisoh, K . K i y a s h i t a ( P e n n . S t a t e U n . , U n i v . P a r k }
Nature 213 ,698(1967) (Febr.l8)
.
The incoming radiation i s expected to charge electron
traps in proportion to dose. Subsequent heating in a temperature
gradient should give a temporary thermopower which « l o w e r than
that of unirradiated spskx specimens due to release of free
carriers from tr.ps.After recombination of these traps, the o i i ginal value of the thermoelectric effect should be restored.
Studies with ZnS are described using uv and X-radiation.
Complications are due to space charge regions due to local
variations in the population of filled traps and contact parah observed
b d
larity reversals.
reversals
meters.These factors cause the
polarity
Other materials including CdF2,laF,SrF2,Car'2,BeF2.
I
'
.
,
Sffecta on
2nd èd. (J.J.Kalinovski, R.K.Thatcher Eds.)
Uattelle Koaorial Instituto,Ctolwibua»$*A9
Kept.DASA-I420-I(1969)
Contenta inoludei ITuclear-Weapon-Burst Environment. .
Simulated Versus Burst Environment. Interaction of Transient
Radiation with Matter. Discrete Semiconductor Devices.
Integrated Circuits. Capacitors, kiscellaneous Electronic
Materials and Devices. Circuit Hardening.Circuit-Analysis
Techniques, aystem Hai'dcning.Bibliography.
OOKWOTITJ'VY -IHDuCBu M KLF.CTRO1? 30J.'.BATiBl.'!OT
','J .0 .Trodden, H .0, Jenkins
O.E.C.J.Soi.Tooh. .22,85(1961)
InvestifiBtions on caârràuta sulfide crystals are
:r 0?
T.;O A'.:J miãü
^«•10—irr.-T-1-jsi^.ii^.n-
/
:AI.LXO:Í VCLT
K. A. Uri c'it, J , G. Trunp
J.Appl.Kiyc. .21 ,345(1950)
are reported for Al. Tho variation of the
bean current density in a plane transverse to the beau,
the effect ou thio trünsvorae dintribv.tion of additional
Al ccattcrini; foil.o, and a practical method of àaz^a
arc k'i.voia. Tiie lattor ia obáainod frou the dintribution
in depth curve ,
.
1
DEVELOPMENT OF RUPTURE I N PLEXIGLAS UNDER THE ACTION OF ELECTRON
RADIATION.
TssHin, B.L., Zaitseva, N . G . , Kargin, V . A .
Dokl. Akod. Nauk SSSR, 113, 380 (1957)
—
Reports discharge patterns produced by electron bombardment in a series of homologues
of po!y(methyl metacrylate) and also in polystyrene and polychlorotrifluoroethylene
(Kel-F). A series of photographs for different doses ore given. The temperature influence
is discussed.
/
/
. ._
00 I
STORAGE 0? CH-4KGE III All ISOLATED MICA PLATE JJUE TO
BME-T iil'fil PAST 33LBCÍPHO1IS
I z v e s t i y a VYsshikh TJchebnj'ldi Zavedoni , P i z i k a : i o . l , l l O ( l S 7 2 ;
(.Bulletin of t h e I n s t i t u t i o n s of Higher Edxication,
Fh; - sics)
,,&
«6
\/
\
*
1473
X-HAY-1NDUCKD CUHKENTS IN ANTHRACENE AND
TETRACENE. Tui'lol, I.; Kallinann, 11. (New York Univ.. N. YJ.
Z. Naturforsch., 21a: 1347-M (Sept. 19C3).
A new method, which avoids making measurements or applying
mi rxtormil voltage while the x rtiyy are on, was used In Invcsti(inllni; (he iunlzation proceí-f by x ray» la orp.aulc crystalB Uctracene nnd mithrflcc'tic). '1 ho followinj; roKtiltfí were oUiilneil: The
x-1'ny-indueoíi twvreiil is litutfi* with cloelrle field «tren^th over
0 lni'c.o rimi;e
of field slrt-n^tliH nnd snturnlcs nl field strpimlhs
nbovc 1Ü1 V/cin; It Is propoitlonal to the Intensity of irrndinlinn
and to the ililrknctiH of the sample for the Borne field strrnRtb;
about ]000 eV nre required tu produce one charge pair in anthracene mul -100 eV in letracene. It was also found thai the saturation field strength Is Independent of the x-ray Intensity (the intensity wan varied by a factor of ten). From theHe re&ults, it was
concluded that recombination occurs mostly l>eUvcen the electron
and the hole from which it was
separated. It was also found that
a lni'tc x-irrodlntlon (8 x 10*1 ergs absorbed) produces trapping
flltcs in the bull; of the cryMnl that trap clmrges and thus produce
some bimolecular recombination, (auth)
__
rj'frtal i s c:r.nd'wiohcd 'beL-.;oon a
prr.cticu.lly i.op.-cotjductii;/; r.ylra"1 chcei
and a» electrode. a)X-r;;vr; and i'icld
are r.pplicd concowd-ttautly .Ai'tcr tlioit
roi.iOvr.l uJic cJu'.rr.e uciii-iuicitGd v.t the
crj/cttil-i.;vlar iutorface xo í.ti-.ourcd \>y
the l:i(v}:t-re'leaüo i:ie>thoâ«'b)x1i.c "bai-ricr
i e c'uui'ijud to a kuoi.'ti oliux-^o Q by li^Ht.
Aftor i'ci;:oval of tbo o:tter:iül field,un
ántcroal tida
vcr&iBts. Unicr X-ray
ioniK:.tion i t wovee tho X-ray produced
ci)!.a\,(.!:; irhicJi j::.rtially coiii-onacte the
ori&itml cliargc.'i'iio roi.iainin^ churgo ifa
then !::oasiiroà.
a V
1596G
(WIIAN-.SA-23) IN-COItli, SELF-POWKRISU FAST
NEUTKON FLUX MONITOltS. Uptin, J. \V. Jr.; brown, D. 1\;
Speur, W. G. (WA11CO Corp., Hichl;ind, Wash.). C Nov 1970.
Contract AT(-10-l)-2170. 9l). (CONK-700904-5). Dcp. NTIS.
from Conference on Power Keuctor Systems and Components,
Willlamsburg, Va.
Tho development of solf-powored fast-neutron detectors for
«so In reactor coros Is discussed. Tim detector is in the form
of n coaxial cable: with a Jte coro, u Mgp diulcctiic, ami :s stainloas-Btuol outor conductor. cllt! in produced l»y the fPn(n,o)
reaction; Ilio i> durny of cllo provides u flow of charge which can
then bo monitored by electronic Infitrumontation oulsidu tho r e actor. A rod Vt I". 1" dlninulor lia.s u sensitivity of about I0~"
ninp/uvj henco, for a flux lovel of Id" nv, tho sensor produces
1 M of dc current. The *lte burn-up rato predicts a burn-up of
only 0.41 x )0~ !5 1/iivt; thla means a 10% drop in signal power
a/tor 60 years for tho slatud flux level. (K.W.R.)
f>70
"
11690
RADIATION-INDUCED ELECTRICAL CONDUCTIVITY
OF POLYETHYLENE. Valsberg, S. E.; Sichkar, V. P.; Karpov,
V. L. (lnst. of Physical Chemistry, Moscow). This paper was
summarized In Khirn. Vys. Energ.; 3: No. 5, •i54-5(Sep-Oct 19G9).
(In Russian).
Full copy of this papor is held by DTIE.
• —»
Tiro radiolndiircd electric conductivity of polymers (particularly
polyethylene) is interpreted with tho help of the Fowler-Hose
model, which is based on n-type (or p-type) conductivity and includes not only the radiative generation of free current carriers
and their recombination with stabilized charges of opposite signs
but also the thermal equilibrium of the carriers between the
conductivity band and t!ie traps distributed exponentially in energy in the forbidden band. The electric conductivity of polyethylene (high-pressure) induced under the action of s5Co y rays was
measured as a function of Intensity and temperature. For the
temperature dependence of tlie radloinduced electric conductivity
of polyethylene, a straight line in the coordinates log a - T with
slope -0.010 to 0.012 dog"1 was found. Some unimportant distortions of the straight line correspond to those temperature ranges
In which hcat-stimulatcd current peaks are observed. (M.C.G.)
I 1 j
* /
fa
112494
RADIATION ELKCTROCONDUCTIVITY AND CREEPp
1
\ /IN
/ POLYMERS. Valsuerg, S. E.; Sichkar, V. 1>.; Stepanov, V. *.j
Karpov, V. L. Vysofcomol. Soedin., Ser. A: 11: 2577-84(Nov
V 1969).
(In Russian).
j
1
Dependences of polyethylene radiation'electric conductivity on
the dose rate and on temperature and of polycaproamide creep on
the dose rate, temperature and loading were experimentally studled. Similar dependences are valid for both types of properties.
Hypotheses on the nature of radiation creep in polymers were
advanced, including rupture of the strained bonds by interactions
with thermal electrons generated by irradiation. The theory of
Fowler-Rose can be applied to both radiation electric conductivity and creep, strained bonds act as electron traps. Some
consequences of the concept were proven experimentally, (auth)
20948
INVESTIGATION OF RADIATION-INDUCED ELECTRIC
CONDUCTIVITY IN POLYMERS. Vaisberg. S. E.: Sichkar. V. P.;
Karpov, V. L. Vysokomol. Soedin.. Ser. A: 13: No. 11, 2502-8
(Nov 1971). (In Russian).
The dependence of the radioinduced electric conductivity of
high-pressure polyethylene (HPPE), low-pressure polyethylene
(LPPE), polystyrene (PS), polylmethyl methacrylatc) (PMMA),
polycarbonate (PC), and two types of polytetrariuorocthylene
(PTFE) on lhe doso rate J, and for IIWE, ps, and PTFE also
on temperature T, was experimentally studied in a i0Co flold.
In accordance with the Rose- Fowler model, the dependence
a - J° • lo p is shown to bo valid when the numerical values
of tho coefficients A and S are correlated with tho traps distribution parameter T, using the expressions A = T,/(T, + T) and
& = 19/IT, + T). Some temperature regions were found to deviate
from this correlation. These temperature regions correspond to
those of structural transitions. The results are interpreted asBurning tho electron traps to be associated with structure defects.
(auth>
i—i />
OIL.
.
1
A73
51154
STUDY OF THE RADIATION-INDUCED CREEP OF
POLYMERS AND OF ITS RELATIONSHIP WITH RADIATIONINDUCED ELECTRIC CONDUCTIVITY. Vaisberg, S. E.:
Stepanov. V. F.; Sichkar, V. P.i Karpov. V. L. (Inst. of Physical Chemistry, Moscow). Vysokomol. Soedin., Ser. A: 14:
No. 4, 899-909(Apr 1972). (In Russian).
The dependence of the rate v of radlolnduced creep of six polymers (oriented and nonoriented Kapron, poly (methyl melhaorylate), polycarbonate, polytetrafluoroothylene, and ntaclir polystyrene) on lhe doso rato ), temperature T and stress a was
investigated. The dependence v ~ J ' V * ' 1 0 established earlier
was confirmed. A quantitative relationship was found for the parnmoters A and P retiuired by tlio model proposed earlier, which
takes account of the rupture of stressed bonds caused by interaction with thermal electrons. The dependence of the radlolnduced
electric conductivity x of poly (methyl metiiacrylatc) and polycarbonate In loaded state on the dose rate was studied. The value of
the parameter A depending on x ~ J* for each of these polymers
was found to be the same as in the case of radiolnduced creep.
f
V
J
I
j
5606
SURFACE CHARGING OF INSULATORS BY ION
IRKADIVTION. Vance, nennis W. (Xerox Research Labs..
Rochester, N. Y.). 3. Appl. Phys.: 42: No. 13, 5430-43(Dec
1D71).
The charging of insulating surfaces by Irradiation with gaseous
ions Is discussed from the viewpoint of basic interactions between
Individual ions and surfaces. Experiments are reported In which
mass-selected b«ims of low-energy positive and negative ions are
used to irradiate insulating amorphous selenium films. The surface-charging efficiency (the number of charges retained on the
surface per Incident ion) is found to be initially equal to 1, independent of the ion species and Ion kinetic energy. As charge accumulates on the surface, the charging efficiency decreases, the
extent of decrease being a function of species and kinetic energy.
The results are shown to be consistent with a model in which the
ion Injects a hole or an electron into the solid and the injected
carrier is trapped In a surface state. The deviation of the charging efficiency from unity arises as a result of free carrier generation in the solid by means of a transfer of kinetic and/or
potential energy from the neutralized Ion. Implication of the
selenium results to Insulator charging In general are considered.
, _ _.
0 I Z>
\
j
',
•
j
i
\
i
\
I
;j
j
!
j
1
•
57919
PENETRATION OF HIGH ENERGY ELECTRONS IN
WATER. Van Dyk, J.: MacDonald, J. C. F. (Ontario Cancer
Treatment and Research Foundation, London). Phys. Med.
Blol.; 17: No. 1, 5Z-5(Jan 1972).
An experimental evaluation of the parameters involved in charge
deposition from high-energy electron beams (10 to 32 MeV) in
water is described, with particular r< ference to radiotherapy. Expcrimental and theoretical values of the parameters are compared,
and a qualitative explanation of the differences is given, (auth)
In agreement with Ke^saris, a large number
of electrons come to rest in a narrow depth
near the end of the distribution -with a most
probable depth Dn.Linear extrapolation
thoanigh the inflection point gives range .R .
T(MeV
9.5
17.8
31.7
(s/om 2 )
5
10
11.7
..
.
OI
i
O
> CKAliGK DBrOSIÍlCIT FitOli HUM b'.:BitOY LL^rilOlí B£.Ui
1 J.Ya!i^v3t,J.G.?.'::ó-.oàounlcL
Hi.uliut.iloa. 3£,Í>O(1S72)
Chaxgo distribution in water produced by irradiation witB
10 to 32 MeV electron beams ssz ie measured by the method
og Gross-Wright, tletall and plastic catchers are used,preferentially tho latter (as solid Faraday cages)» The lateral
sprad of obargo deposition (normal to beam direction) iras
also measured. Charge deposition profiles, tranasaiesion
curvos (giving +'k° number of oloctrons travessing a specifio
depth),extrapolated rango, raost probable depth(at which,
maximum charge is colleoted) ware determined. Results are
Practical rango R^ = 0.60 T - 0,71 g/cm^
Most probable depth D » 0.48 T - 0-91 g/cm
2
Practical(extrapolated)range R «0.55 T - 0.71 g/cm
vhero T is tho Itinetic electron energy in MeV.
i"
-"••"
P0LA1U/.ATION I13DUCS35 BY HADIÍÍSION^IÍ PERSPEX
V.J.VanhuysojO,J«Vanpraet,J.P.Van Landuyt
Nature
Optical proporties of perspex irradiated vdth 2.5 MeV electront
are reported. Irradiated blocks were observed with a polariscoi
polariecop*?. After irradiation an interference pattern
could \>e soen that behaved as if the block was an uni&xial
doutoc refractive crystal, the optical axis coinciding with
the direction of the electron beam,The picture ditappeares vcrj
quicWy at first,slowly afterwrads. If the sample v/aa dischar*»
ged while the intei-ference could 3till be seen, this disappeared immediately. It is concluded that the optical
properties aere due to an electrical effect, only a fraction
being due to the mechanical strain. Something like the Kerr
©lectro-optic effect is considered,
?
}
\
I RADIATIOH-ITTDUCED CURREilT AiiD PH0T01Í-INDUCED DEPLECTIOIJ
' OP J3LSCTR01ÍS IN DIELECTRICS
A.B.Vlaàimirskii,Yu.B.Vladimirskii,G.M.Zalcharov,T.I.
Nikitinskaya,P.A.Rodnyi
Pizika Tverdogo Tela 11,3649(1969)
Translation Soviet Physics-Solid State 11,3066(1970)
Reports measurements (apparently of short-circuit currents)
with X-rays of up to 30 kV,using samples of LiP,NaF,CaP2
single crystals,sample diameter 17 mm,thickness 1.5 mm.
Polyfluoroethylene was also studied. From 10 to 15 KV
upwards currents are porportional to X-ray tube voltage.
Only the photoeifect was found to be operativ.The Dember
effect(movement of ions in a concentration gradient) was
too small to interfere with results.lt should be noted
that the electrodes were separated from the samples fey
so that electrons could not be exchanged between the
electrodes. ^Currents were of the order of 10"*-^ A for
about 600 R/sec.
.
&(/
OP ITUCLlíAlí RADIATIO1T Oil THE DIKLUCTKIC PARAJ-JSTERS OP
I1TSUL.VÍ JlfG 1 iATEi'.l ALS
K.A. Vodopyanov ct_ a l .
Energ. 1,4911(
Temperature and frequency characteristics of dielectric
pornittivitjmd .'loss an^le in polyethylene,fluoroplastic,
and other plastics vero studied "before and after exposure
to sawna, radiation.
\
| A POSSIBLE EFFECT OF LIGHTNING DISCHARGE O N PRECIPITATION FORMATION
if PROCESS.
i Vonnegut, B., Moore, C.B.
]n Physics of precipitation. Washington, D . C . , Am. Geophys. Union, 1960. p. 287.
Dielectric breakdown of methyl rnethacrylate blocks electrified by electron bombardment
is considered as an analog to lightning discharge processes. From the study of the breakdown figure it is concluded that the spark which occured" in the plastic did not neutralize
a good part of the charge within the plastic but merely balanced this negative charge with
an equal and opposite positive charge. •
0""::."•"' SXCnV'OE III A UI231.ECTHIC 2C13AJÍTJÜD '.TJ-T:'. £J.
A • .1. Vcrobcv, 0.71. iVdol'-i:.-ov, IT. P. Tubalov
Fi B.Tver .Tola 1 3 , Z&liVn)
t
1 !Mtí BSIiAVl©ft OP Ttte EWÉJiaY ACCUKííLATIOlT FACTOR FOR BREUSSTRAHLUKG BEY013D A PLAKE LAYER III A IIOHOGBUBOUS MATERIAJ>
A.A.Vorobev,V.A.VoroTDev,G.P.Tarat;ov
Izv.VUZ.Fiz. 1,,92(1971)
'
DEPTH DISTRIBUTI01Í OP iLBSOffiBED EliBRGY MU> EOSE III VARIOUS
1ÍATERIALS DÜRI17G IRRADIATION WITH BREKSSTRAHLU1IG OF
1-iAXIi.iUI.i ENERGY UP TO 1000 KeV
AoA.Vorobev.V.A.Vorotev.A.V.Puslikin
I z v . VU2 F i z . . . . _ /
. n o a (
Sov.Phys. J . — - - - —-
Lot
/7 v
VOLUME CHARGE 111 DIELECTIíICS PHOÜUClsii» BY AIT EL1SCTBOIÍ B3AM
A. A. Vorobevs Q .33. Jivdokimo v, H. P • Tubalcv
Soviet Phys.-üolid ütate 1^3116(1972)
Electron injeotion produoeá a negative volume charge.
This can be explored by investigating electron transmission properties of tho charged dielectric after
irradiation (of.Bowlt). Such measurements are repoi-ted
here.Ktoí Ploxiglus disks were charged with 0.8 to 1.2 KeV
electron irradiation beams of 0.5 A/cm* current density
and 15-20 sec irradiation duration» Subsequently specimens
were irradiated with beta particles from a Sr-Ir source
whose penetration was measured for periods up to 10 days.
If no is the number passing through an uncharged sample
and n that passing throu&n the charged sample, the
function 6 = (n-n o )/n o decreased with time.EsEx After
irradiation with O.tí and 1.2 lieV eloctrons it changed sign
and subsequently decayed again. The effect is interpreted
by acsuuing, according to Clross1 measujenents, that
the negative injected charge decays faster than the
J Tociitive coi.ipenf3».tion charge occurring at the non\
j irradie.ted side of the Dar.ij.lo. The equation for the
retardation oi" the beta ^articles io written
dT/dx = eB(x) - B/~ 'S(x)J ^-^e T is the kinetic
enor£5' at depth x, B tho specific enor^v loss, eE the
retarding electrostatic force. For the shorted dielectric
tiven tho range reduction
T
V/~x(l" )J 3"2(iB/d'J?' )df£"
0 = /
'
.
-
•
•
'
•
\
EADTATIOli Oil THE ELECTRICAL CONDUCTIVITY 0]
B. K.Vul
Fiz.Tverdogo Tela <3.,2264-,'" " : (1961)
translated Solid State Phys(Soviet) 1962,No.3,p 1645
Current-time curves are given for various dielectrics
(quartz,polyethylene) for different dose rates, applied
voltagesfntemperature3, K M Riae-and decay curves are investigated. A theoretical treatment is given.
,& ,
lrfl
CONDUCTION MECHANISM IN GAMMA-IRRADIATED DIELECTRICS.
Vul, 8.M.
Acta phys. Hungar., U , 225 (1962)
Refers to behavior of quartz, polyethylene, sulfur, ceramics, and similar materials. They
can ba divided into two groups characterized by a different dependence of current on liri.r
of irradiation. For one group lhe current increases steadily with time, for the other the
current attains with the inset of irradiation a maximum and then decreases. A theory is
developed taking into consideration the recombination coefficient and the concentration
of traps for eleclrons and hoies.
,
] THE EFFECTS OF GAMMA RADIATION ON THE ELECTRICAL CONDUCTIVITY
OF INSULATORS
B.K.Vul
Soviet Phyfiics-Solid S t a t e , ^ , (8) ,Fel>.1962,p.l644
bv>^
i/V
21480
£LF.CTIK>N HKAM ANO FLASH X-HÀY DIAGNOSTICS.
Walker, Jack V. (.Sstidia l.aba., Alliuqucrque, N. Mi:*.). IKK li
(lnsl. Hloc. Klcctron. Kiig.), Trans. Nucl. Sei.; NS-17: No. C, 28494(DÍ;C 197U).
From Conference on Nuclear and Space Radiation Kffeels, San
UiCgo, Calií. Sue CONK-700713.
A review oT some diagnostic techniques and'instrumentation
used ai Sltndia Laboratórios for studying intense electron beams
nntl laboratory pulsed x-ray sources is presented. Included are
descriptions of current moniturs, radiation sensitive polymer
films, iu\ü calorimeter arrays for beam enerny density measurements. Also discussed in üu: real tiuie-on line digital computer
used for calorimclry measurements, A new technique for nieasurlily electron energy as a function of time is presented and
representative data from Sandia's llermes-ll facility are shown.
Those data a r e in turn used wilh a Monte Carlo code to determine
the bremsslrahlunj; si)cclrum, which is compared with a direct
photon measurement made with a lar^c Compton spectrometer.
Finally, a discussion is Riven of the use of these data in radiation
cHeets experimentation. The results of combined photon-electron
transport calculations are shown which demonstrate the edge
and interface effects which a-.c important for thin and inhomogeneous samples, (auth)
/ (bQ
® '
\
\
ObaraotoriGtica of tlic uuüiinen:
Hei'KiOsi i.acHine «toi-os 1/^ i-J of oner^.',clelivcr!J COh'J ir. 1C0 no puluo
of 11 KeV, nx.boaw current boir;;; SO
'
):A. A 60 mil '2a t a r g e t given X'i'or.is s t r t J i l u n s . EBBAtStores 100 kJ,i-.oJ.ivcrB
10 1-J in ?0 na pulsou of 3 Y-bV «nd 50
kA. I t vrill 'oe oxx-zn.-cd. to give i:ore
than 100 MA, 1-2 l.oV,allowing !>->-•
doses of 2 - 3 kcal i n 0. irerouss Givea
1/2 kJ i n 30 ns a t 3oo J'.cV and 75 3'^
In the development stages kaoiiinc ío
3 to 10 1I'A. a t about 1 V.eV,
I ; I S T : Í I 3 U T I O : ; AT AIIL ::SAIC
1)I^PEI;B::T Í.:A^KÍÍIALS
viia
Í,;Í'I;:J.''ACÍD OF
J . A. Yiü.l 1 , :-J . A. B u r k e
IBUE.Transactions Uucl .Sci. lJS-17.,Ho. 6,305 (lg?0) '
Profiles in Al and Au adjacent to materials cf different Z
vrere r.e^surod vrith Multiple parallel plate ionisatioii ch&
Lose àistribution varies significantly at high (1.25 l-.eV)
£ami.ia/£ cn&r^ies i/here mass eaor^.- coefficients differ relatively l i t t l o from naterial to material.Enlianceir.ont or r e duction of doso i s very sensitive to the direction of
incident photon beam.Ener/x- deposition in a r.atorial i s
'enhanced ".ri.en i t i s next to one of lo">,rer ato:.;ic nur.:ber provided farina bean ponctratos f i r s t the loo Z uatoi'ial.A
rcversi.l in bean direction reduces the doco to a luvc-1 'colo
írhat i t -,;ould be for tioh either s.iatcrial alone.
(Air Force Cambridge lies.Labs. ,3cdford,íáisD.0173C)
ELECTRICAL CONDUCTIVITY IKDUCUD BY IOHTZIHO RADIATTO-J Hi
A.J.Wam«t.,P.A.Bullor,H.O.Sordlin aass K>"aiSSIC KAT131.ALS
J . a p p l . P h y e . 2^,130(1954)
!
Conductivity-time curves a r e obtained» After a s t r o n g and
, prolongued i n c r e a s e t h e c o n d u c t i v i t y e v e n t u a l l y i s found
t o decre&.so.
bfi
67755
RADIATION DETECTO»! SOLID STATE RADIATION
DETECTION USING AN INSULATOR DIÍTWEEN THE EMITTER
AND COLLECTOR. Warren. Hollr.nd D. (to Babeocl: and WIIcox Co.). tl. S. Potent 3.003,793. 7 Sc-p 1971. Filed 1 Aug
1P69,
An improved self-powered detector which affords a prompt r e sponse to changes in the neutron and |,'umtna flux Incident upnn a
ylterbium emitter by using a thlcknes* of insulator between the
emitter and collector that is sufficient to absorb delayed electrons
emitted at a lower energy level from the emitter o:.d yet allow
prompt electrons emitted at a higher energy level from the emitter
to reach the collector is described, By thus eliminating the delayed elections, tho signal output current of the detector represents the instantaneous value of tho incident neutron and/or ramim
flux, (auth)
iioh:u:Liiii£:-av£i:siw von
,j
h.F.liarrikho/f
z.Jui&v.yhycik
ISO
IB.,44,89,95(1964)
\
«775
PHOTOCONDUCTIVITY IN r-IHRADIATED ANTHRACENE CRYSTALS. Watnnabe. Ynsutnka; Inulshi, YONIIIO. Toehnol. Hep. Oonli.i Univ.; 20: 25-:il(Mnr 1970)
KadiiiUon cliectu on cnrrlvr drift mobilities nnil lifetimes were
studied In nnthraccne single crystals irradiated with y rays. Measurement of the hole drift mobility at various temperatures and
radiation doses show that for dosas above 6.0 x 104 r, holes Interact with n new defect center introduced by y Irradiation that is
located about 0.4 cV above the valence band and have a concentration of ~10 l s cnr 3 , and the effect of temporary trapping at shallow
traps in tho host crystal is not important. The hole lifetime, which
is 25 ii see before irradiation, decreases to a value of 6.1 M sec
after a dose of 6.6 x 10* r . This probably is due to a large cross
section of '-10" l5 cm' for holes of the deep center that have an
effect on hole transport for high radiation doses. The lifetime for
electrons also diminishes when the total dose increases. A similar
tendency is observed for the mobility, as its temperature dependence remains unchanged, tauth)
\
ELBCTRO1T I1TJI5CTIO1Í TECHNIQUES POR INVIiSTIGATIiíG C0IÍSUCTI0IÍ
PROCESSES 111 LIQUIDS All» SOLIDS
P.K.Watson,T.K.Clancy
Rav.Sci.Instr. 3.6,217(1965)
The conventional cathode of a conductivity cell is replaced
"by a scanning electron bean which injects a uniform charge
pattern into the top layer of the (liquid, or solid) dielectric. A current or a uniform svjrface charge-buildup is measured, by mean3 of a second electron bean that I>CLVSS
parallel to the "injection" surface several r.dllir.-ctcrs
above it and vrhoco deflection ie a measure for the surface potential .Steady state and "transient processes can
bo investigated.
IIÍ VACUUM
J ^ r í - M i v e . 38,2019(1567)
lS::T>eririonto vi th dieloetrica subjected to 3!> to 75 no
hi.'J: cnerjjy electron pulsos choir strong ini'luence of cono
ari;;lc of dielectric on insulation utreiv.th.TI'cory assuMcc
that electrons are emitted from surface by th'-Tr.:ionic
oiíÚÉSoion.Rtito depende on erjuare of electric field strength
because electrons are "heated" by the fiold according to
an activation lav o~.cn(-Ii/kT0) vhere To tiie electron to;.v
pcratxu'c, i'.nci ]:T0 prop» to energy acquired in tho fi.-jld
vhioJi i s pi-oportiorjil to o-.aiaro of field strength. The
ei.dttiuc surface char^'ccup positively,dr;.w-inr; eventually
other electrons into i t where they vrill i.uiltivly by
aecondarj' eniisciou into bi~cnl:v.ovni condition.j?iiua i;hilo tJie
brealidoun ic produced by the Deeouduries, curface char cine c
and tiiuü tine lac i s governed b;: thcrnionic cniooio'.i of
hot electrons fron \ritliiu the dielectric.
.
PJIOGJáoSlíS AG00i-.PAir/IlIG i.HGAVOLT JJL
IOir
Hi ^IKLl-JCTKICS
A.l.'atrjon, J.lvou
\
j . A p p i . M I J - B . ;i2,5 c ;35(1968)
'i'Jiiok dielectric samples wore irradiated -..'itli 1 i.eV
clootroas. 'i'lie temporal groi.'th of tb.e external field fi-oi;
the trapped ciiargo vras punctuatea by either tots.1 or par—
tial collapcet; associated vritii electron euiasion. c-.na
follov.'ed by JJLSOS before the process ropatod itself.
Sücondarv electrons ara tliouslit to 'bo licated by the tjroviiiy
internal space chargo field, until thoriüionic ei.iit.sion
induces a ro^onrative cP-'O'.fth of porsitivc »ui-faoo charge
sufficient to oppose it. Electron cuiasion then ceasea
until reeoLibination can restore tne cvvcaiclo ourface of
the dielectric to a field-free condition fro;.! which it .jrovs
a^ain. Analysis of the r.oaol proves it to be ad9cv.at9.
:
;
]
j
I
'
i
1
I
j
!
lELECTEOU IHJECTIOIT TECHNIQUES FOR INVESTIGATING CONDUCTION ^
PEOCEÜSES IN INSULATING LIQUIDS AÍÍD SOLIDS
P.K.Watson,T.M.Clancy
Rev.Scient.Instr. 36,217(1965)
Describes a new type of dielectric cell which avoids using a
metal cathode. An electron beam injects a uniform charge patterz
into the sHsiaBEpcaoaaEEBoailxE±EBdbaaHxfeeEsna top layer of the
dielectric. The bulk current through the system is measured
by an electrometer connected with the bottom electrode.
&xgEa3±Hgxs±EEix A seconàS5S§i??on beam passing 7 mm above
the top surface is used to measure the surface potential.
It indicates the charge build-up and charge decay in the
dielectric.
•••{
7o
JÍJU.'{:\j.'.i'i!/J
'<•• i i v .. : -
fiji.'.
; : ; , / . . \:c:-.-f?s - . L o r i
•'.Tn"iJ:i
onn iin
n ijpao
n"iJ:i c l u o tt rrii o
ijpaoe " oywpofoun^unc
os.L.-.il>s.rittai.i)Tt-;li. 35> 1.JOJI3"!, Pf.por 7«
25-26, ..'o.^tin^hoyjjo
i".f.':ifin:i'(..';:ic.ot.fi Í-'..«VÍ< roriortocl >-<n polciriar; t i o n cnrrwitr-. a t
cliff(•:•••.• n t doiio r u t e s f o r e l e c t r o n ami fí&nmia rn.-.l:i-ition. The;
tiT.nfjj ' n t cuTvoirt cari 'tic. r'.-yi'usvjntc'l ;-.u o. Bum of f o u r oy^ünontit;!
oxponeirtin.i.H, It. Irs foiui'.l l.ii:..i tl.'C ij.;.io constuvrto u r o
pr<v;-fcio.-,."ljy in:Up>.n;ioni of CIOEC vi-.to, rmt t h a i t h e £j.i:)lituíc,q
of t)u triiiun.c)il. oaüviünantrj ac v/oll p.;-; t h a t of I'IO r>le;t(";y s t a t e
. component inorousje ,/ith dose r a t e , >b:.r.2.tk«K>:3;ríAÍ::tsr:»r2"í::-:t:
I t irj <x>no:iuü<:» t h a t t/io duta do not support a KO.-HVJ chf-.r^-o
poluriiieffcu on p.:jt-ociat:jd váti: oloctrorio e f f e c t o . '.Lfitlior the
polü,rizi:.ti{jji occurs in the buük of fno i : : a t o r i a l .
íí»
STUDIES OF THi; PERSISTENT POLARIZATION OF SINGLE CRYSTALS SrTiO3
EI.ECTRETS PRODUCED BY NEUTRON
BOMBARDMENT.
Weil-., H.
Pciper to be presented at the General Assembly and International Congress of Crystallography, 6th, Rome, Sept. 9-13, 1963.
Neutron bombardment of SrTiO3 electrels is found to produce ionic displacement and
surface charges which remained unchanged over a measuring period of 1000 hours.
Annealing the crystal reduces the surface charge to zero, but restores the lattice only
partially. It is concluded that potential traps play a role in the heterocharge effect.
\
X-!!AY I1D/ÜCS1) PHOTOCONDUCTIVITY IE DIELECTRIC PILL'S
H.C.Weineart, E.H.Barlott, H.S.Lee, W.Hofer
IEEE Transactiens llucl.Sci. 1IS-19, lTo.6,15(l972)
Induced conductivity was measured in filns of polyethylene
epozy,polytGtrafluoroethj'lene,polyethylene terephthalate,
polyirdde, and glads, "by X-ray pulees of about 40 ns ,
width, about 10 keV energj', and dose rates of IO'' to 10
raà/sec.i'lras were 0.05 to 1.25 mm thick. Induced photocurrents were found to obey O^m's law at biases up to
1 kV.Above this value, the peak conductivity from some of
the 0.05 Him samples
increases slighly more than linear
vãth the field.Glass samples exhibited no delayed conductivity, other showed
various amounts^ most the fluorocarbons, an effect compatible with some sort of fielaassisted carrier generation (l-oole-Prenkel effect).
lla&mtude and time dependence of conductivity signals
could be quantitatively explained by a simple trapping
model .
.
j
j
~fOO
~IO1
DM -1. Ch-trç? Sloi--j,yj in Electron >B:>riterdod Polymer
FJ lino, J . ]í. ""Wi:íJT~flTíd G. H. EKoüM, iv-1.1 Tolf-j^oira
Ii-ljqr>torlt:s, K.irray U i l l , U.J.--A, varloty oí' 2 v~- ^5H
]io],V7in;r films, fucli n:-> j..olyt'tiiylcn(i tL-rejihthalate,
IiOlyonrbon«t(-f, and i-c-lyfluorootíiylenüpropyltne (PK!1)
h-'ivc- been irnui Inted vfit.h n!onocner£jc;ticí electron bcar.s
in lhe energy ranço 10 K&V to 1 MeV. An in related
cxi/OrlcifntHlj qufinijjon/.untint ch'irc«ífi OJ' opiioaile Ri£n
pn the two aíúco of tha filma ore prooent nftor
ídintlon. 1L ajoenru lhot tho negativo charetíc nre
jifiíi electrons. Chrirce densitienj ris mentiurecl by
Induction metliodr., nre i n i t i a l l y of the order of
:LO-7 c/cm^f âcürcnr.lnz to about 2X10-8 C / W . w i t h i n a
period of a few months. On FKP the rcnaJnins charge
decays with a time constant of about 100 years at
room temperature. At hlfíh relative humidity, water
toe Ieculc5 absorbed in the polymer vere found to
( l ) rcversibly componoatc the externul field of the
svitice chnrge» by menus of t h e i r dipolar characterifitics
avid (2) cause at) increase in conductivity leading to
i r r e v e r s i b l e charge decay with time constants of
3 'to 5 yjars on FEP at 35°C and 9056 r e l a t i v e humidity.
705T
\
•THAÍÍ3IEKT CONDUCTIVITY IN CAPACITOR DIJÍLUC^PICS FC>
R.OT/.TION PULSE3
'
'
I!cV/.'.Viokle5n,H,Kutley,J.M.Ferry
IKES CP 63-ll86(June 1963)
.
IEE3 Trc'.naactlons Nuclear Sci. 1TS-I0,71o.5,131(1563)
Eeportfs on measurements performed v/ith X-rays3,gamma rests,
and elcctronsj, in mylar,Vitamin/ Q, fixed paper,ceramic,
tantalum, and mica capacitors, for dose rates between
10 6 and 109 r/s and pulso vàdtbs from 0.2 to 11 me.
The conductivity current depends on the pulse shape and
the the form of the current-time curve for rectangular pulse
shape» A superposition integral is given which would
permit to calculate current forms for different pulse
shapes provided the time dependence for rectangular pulses
is exponential,
\
'
;
,
;
.
f
I
'
»
j
UIG1I ELECTRIC FIELDS Hi SILIGOH DIOXIDE PF.ODUCÜSD 3Y G0H01TA
CIIAHGI1IG
'
H. "Williams, LI. H.'.foods
J l P h ^ 4 1 0 2 6 ( l S 7 3 )
I
j
1°1
current were measured.Both decrease with time, rapidly
first,slowly later.When the current has dropped to 10~°A/cm2,
the surface potential changes only a few p per minute and
the field across the oxide has become nearly stationary.
This field K g is compared with the conventional breakdown fiel
,noting that there appears to be no destruction of the
sample in these experiments.Eo is independent of the conductivity type and the Si doping level even when it is
degenerate«when the free surface is charged negatively, B is
about twice as large as for positive values. Appare'otly tie
intrinsic dielectric strength(7-$) x 10$ v/crn) could be
obtained. —In the measurement the SU3& a value that the
current through the sample equals then incident current.
r
rr
iTs n: SOLID I:ÍSÜ"J.A.I:O:':S
1
u-rc^to anel curreute induced by 2^0 koV and 2 ,;eV X-rtiy
in polyc'l/hyloue f:ü.r.',,i: t.nd v.ulsje-.iiiduoec'. .tr.v.iiniontc in l'sp
oableo \roro i.;c\.nu:r.'Ci.l. H^atl;.- a uanuirich Sitn-ucturo war, uuod.
'iJarJc ooiiduo'tivi'by,dnaucitiá corkl.,;.nd Coürton current -.;c.ro
iioüourod. iluducccl v.ua Couptcm current vnero j'ro'o.to j i a ,
\-Jici-G ^S i-rao to.oc re;-to and 0 . 5 » n i l ,n liDin- Cifioreut Tor
ijid.oond.iind Ooi.ipton om-rcnt. Sc'i.uV.rct; tmluoa a t ±oo:.i C vrcro
4 A° at ÜY5 V/'om t.iui. 10 k?./r.in to 2500 A0 r.t 37 l-»"V/c::i wid 1
kk/inin.Lo'.JuP valiMJD ^rc found at lover T . l t 5a boJiove'.l that
a t lo-.r T íiuu lovr {í olcc-trons u*o r o c t r i c t o ú to ncflr -ilioir
parente,vhi3.u at hi^h p and Mc|i '-Í1 they ray caowpe i.-er/ianotitlytkoanurwiionts of cJiar^e oollcctod during pulaod oiieratio
showed strong p o l a r i a a t i o n effeot,deoroasin£' for suoceõàive
pulaos.Both apaoo cherge and àipolo mechaiúsma are oporativp,
12446
(UCIU^-71353) CONTKOJ.I.ED-TI1ANSIENT TECHNIQUE FOR MEASURING RADIATION -INDUCED CONDUCTIVITY
IN DIELECTKICS. Winslow, John W. (California Univ., Livermore. Lawrence Radiation Lab.). Oct. 8, 1SG8. Contract W7406-eng-48. 15p. (CONF-6S102& 1). Dep. CFSTI.
From Conforcnoo on Electric Insulation and Dielectric Phenomena, Buck Hill Fulls, Pa.
Radiation-Induced conductivity In dielectrics v/ao eludled unlng
the behavior oi polyethylene and polyntyrcne during Irradiation.
Measurements were made under constant irradiation (uljoul 50 rad/
sec E0Co gammiis) with electric fields limited to the range below
«bout SO kV/cin. The two materials were found to display a type
of volume photoconductivity which may be useful In examining
conduction mechanisms and related internal phenomena. Mechanisms responsible for observed currents are not obvious but
they are shown to be insensitive to trace elements and minor
constituents. Small sensitivity to neutron bombardment su^geste
structural imperfections present in large concentration. (F.S.)
'
~7 f\0
' VJ
t
\
\
•
A CONTROLLED -TRA1ÍSIB1IT TECHNIQUE FOR MEASURING
HADIATI0K-I1IDUCED COiiDuCTIVITY III DIBLBCTHICS
J.VJ.VIinslow (La-rfrence Rad.Lab.,Un.Calif ornia,liiverriore,Cã
Iníl^68 Ann.Eep.Conf .Slclns. i?AS-NRC Publ.j.','O5, '
Washington DC 1969 , P.185
Keasurcments under constant irradiation (60rad/sec
Co
gammas) in. fields below 50keV,up to 1.5 Mrad, irith
polyethylene and polystyrene.Values are strictly
proportional to inverse thickness,indicating existence
of a bulk phenomenon..Appreciable transient effects w
were found when the voltage was changed stepvise.
It is concluded that the conductivity measurements can
give information conduction mechanism and internal
phenomena . related to it.Sensitivity to neutrons
is surprisingly small.
I lO
!U:)TA?I0r~TNDUC3:) CONDUCTIVITY IH IKSULAT03S.
H.J. Win tic, Unyal Military Coll. of Science, Swindon, Wilts,
Bnç.
Brit. J. Raòiol. v.33, p. 706-7, 1 W i960.
It is shown that experimental
results
from many
p
u
y sources
surces are
are
i t t witli
itl th
lti
C?'
10
0~
~ 11 JJ H
H where
h
'i th
consistent,
thi; relation
C?'= 1
O'is
the reduced
cnductivity
e
s e r a t e in
m i n u t 1e'.
.
co
onductivity in
in -'"i •
er
ra
a"'* and
and H
H the
the d
dose-rate
in ra3
ra3 minute""
Polythene is an exception and the relation^
is found to
^ =
hold over a wido range of doso rate.
T'lii! CUKJ'JCTIVITY OP POLYTHENE UKDElí 0A.VMA IRRADIATION.
1
77/
^
International Kournal of Applied Radiation and Isot^tícs
8,132(1960)
The elootrioal conductivity of specimens of polythene film
was moasurad in vacuo with and without gamma irradiation. The
specimens were 0.0Z'i> in. thick, and silver electrodes were
evaporate-.] onto each side of the specimen to provide as intimate
contact as possible with the dielectric material. The meaourem&ntQ were madc^at about 25riC v/.ith a dosa rate of O.Ol^.r/mir.
from a siiuill 0o oi) courco, ueing an applied potential of 90 v.
Data are tabulated and results are compared with previous measurements by others.
\
7/<2
Reports influence of dose rnte,rise time, decay time,
^
and variations observed vdth different specimens»
Rise and decay times were found to be of the same order>
of of eorae hours» Conductivity increase was found to be
proportional to a power of dòoe rate, with an exponent of th3
order of É U & Í X about 0«8 »
1
taüPUSIOir KÜCOISIIIATICIT Hi l'OLYEmiYLKira
6
il.O'.T,.ri title
Nature 1^3,478(1963)
The decay of conductivity vriLth tine after irraodation fljas
previously been interpreted in terns of a hyperbolic,
bimolocular related, recombination mechanisn. In this note
a diffusion controlled process,leading to first order
kinetics, is proposed..In case of polyethylene,irradiated
vith S;0 keV X-rays, at 1 - 10 R/min, recombination
is governed, by a first odor lav during the first 10 min,
later it becomes hyperbolic.
"
7/3
J EXÍ0ÍÍE2ÍTIAL THAIJPIirG AlFD C01TDUCTIC1T PARUSTERS III P0LY1IS2S
I • H.J.wintle
Photocher.:istry and Photobiolos' j6,603(1967)
Photoconduction and gammaray induced conductivity can be
interpreted by a model assuming an exponential interband
distribution of trapping states.
i
!
!
!
?J)0
I DECAY OF STATIC ELECTRIFICATION BY CONDUCTION PROCESSES
H.J.VÍintle
^ POLYJÜTHYLEUB
J.Appl.Phys. /J1_,4OO4(1-97O)
Paper develops the theory of transfer of, charge from an
olectrifiod(charced) surface layer through the bulk of the
dielootrio for transient space-charge limited current conditions. The inclusion of ohmic conduction and of diffusion
is discussed. Comparison with data for uolyethylene indicates
carrier mobilities of the order of IO""1-*- cm 2 /V sec at room
temperature.
ref.M.Ieda,G.Sawa,U.Shinohara. Jap.J.Appl.Phys,_6,793(196'/)
itóCAY 01? WX.CÍ0SS CÍÍAUG3 ET DIM-EOi'i:.lCS HAYETQ SJIOlííED
H.J.'Wintlo
J.Aprl.Phys. £2,4724(1971)
i-'lcv? equations are c.orived for the: disciiar^e of diolcctrcs
having an arbitrary initial charge and shortod electrotiec»
Tiie case of an initial charge distribution which is uniform
down to a given depth y is discussed in detailj including
under non-iisothermal conditions. It is ehovm that only a
snail fraction of the initial charge can be observed in
the external circuit while a creator fraction is retained
in the specimen when the external current flow ceases.
I'D
LPJ?}
SUKFACB-CIIAKG3 DECAY IJT IHSULATOHS WITH ifOI.'COIiSTAli'J? l-XXBIL!
A1TD V/IT1! DB3P TPuU-'PIKG
H.J.Kintle
J.Appl.Piiys. 43,2927(1572)
Motion of charge initially deposited on the free surface of
an insulator is studied.Results are given for a)mobility
~l\l
proportional to a power of the field b ) proportional to a
'
power of the free-carrier concentration c) fast deep trapping going to completion (e.g. until all crmryTr. traps are
filled).After one transit time the surface voltage becomes
a unique function of time. Polyethylene results do not fit
this scheme,discrepancies are discussed. The observation
of thermally stimulated currents in thin-film elecjretrs
implies that they are electrically inhono^eneous.
The treatment of deep trapping assumed instantaneous trapping
to level given by number of deep traps, rectangular distribution, and refers to caso where leading -edge has already
reached electrode. The situation before this has happened
was treated by Many and Rakavi>Phy3.Rev.l26>1980(l962)
I
[
Ifl-WíiíICAL COinXJCTIVlTY OF GAiaiA-IKIlADlATED 3 - MP GLASS
Á3Q OP HIOTOIOinZED 3-3'ÍP-TJáPD DURIIÍG VÍABI-iIlíG FROM
40 TO 77°K
B. i.'iseall, J.B.Vfillard
J.Chem.Phyc. 4.6,4387(1967)
A variety of experiments are carried out.Positive and negative currents aro observed. JSach of the positivo peaks in
thcjiitri.mp opectrum Must indicate a discrete population of
chaise carriers whioh, in the absence of an applied potential, is able to diffuse at a certain temperature of the
matrix irith consequent neutralisation or deeper trapping.
In the presence of a potential the trajectories induced
by random thermal motion,and perturbed by the trapped charge
in the matrix,are altered to give a component in the direct!o ~74g
n of + and - charge which is recorded as a current flovr.
Reduction of tho current by blocking electrodes indicates
lof.-r. of electrons from the sample at the anode and gain at
the cathode vhen they are not blocked.The residual current
in tho presence of blocked electrodes indicates spacecharge build-up competing v.'ith neutralization ao the
sample -.rarias. In the presence of blocking electrodes
the; .uverujo uictc.nce of chi-,rt;o i::ovencnt in the eyetei.i is abouJi
l/5_of that withconductins eloctrodes.
•
I
OOSIMETRIC PROPERTIES OF ELECTRETS.
\
Wolfson, J.L., Dyment, J.C.
(1961)
Iiesin-c-a-nauba-uax bfoovax e l e c t r e t s hove been i r r a d i a t e d with
a Co^o Gource i n a shorted condition. Phe decrease of the
surface charge,nea.curod by an induction p l a t e method,is used
f o r dose determination.Charge decreases exponentially ;rith
dose, but the reduction i s found to be of temporary duration,
the charge recovering viithin about 2 weeks.It a u s t be concluded
t h a t the effect i s mainly due to the a i r gap s t i l l e x i s t i n g
between d i e l e c t r i c and covering metal . f o i l .
.. _ - •-• —
SSLF-PO'.VSRSD KSUTfiOU D3TECT0H TSSTI1IG. IN THE SIG ROCK ..
POINT REACTOR
H.S.V.'orsham,Jr. (3abcock and W i l l c o x )
ANS Annual. M e e t i n g , J u n e 2 8 - J u i y 2 (l97Ô)Los A n g e l e s , C a l .
7/7
201
BACK-SO ATT LOTTO OF r.JíGAVOLT .-XíOTRÜlíS P.'JOw TI'.ICK TARGETS
ft,
A. '.Vri
i r t , S. J.
G.G.
Trump
K. A.
'.Vriggirt,
Trump
HNAppl.Ph.ya. «,,687(1962)
Measurements are reported for normally "inoident electron
beams in the 1 - . 3 V.oV rance. Maxima» AxmsxiK For 1 KeV
electrons?, a maximum backscat'toring to incident number
l-f-tio of 0.47 was founci for U, and a minimum of 0.1 for Be
with 1 ;<1eV electrons. The enorgy relation was also determined,
by a calorimetric methodé
\
ELECTRON INJECTIOH AND STORAGE IN SOLID DIELECTRICS
Kenneth Wright
In Conduction and Strength of Dielectrics Symposium,
MIT,Kresge Auditorium,Kay 28,1964
The suggestion is made that the maximum potential in an
electron bombarded dieleotric due to the trapped electron
charges may exceed the accelerating potential.
7/?/
if TRANSIENT EFFECTS OF INDUCED CURRENT IN POLYMER INSULATION
S
UNDER IRRADIATION OF AN HIGH ENERGY ELECTRON BEAM
X.Yahagi
Waseda Daigaku Rlkogaku Konkyusho Hokoku No.24,49U963)
Electric conductivity was measured during and after irradiation
of polymers (polyethylene and polytetrafluoroethyleno)
by eleotrns from a Van de Graai'f generator» A space charge
field was observed by measuring the global charge of the
specimens after irradiation.
«
I
INSULATION RESISTANCE IN POLYKTHYLMTS AND TEFLON UND/itf
GJpiA-
HAY AMD ELSCTROM-BEAM IRRADIATION
{
••
K. Y a h a g i , K . S h i n o h a r a , K . M o r i
7£ A
El.Eng.Jap. 8^.,52,March 1963
Chitroctoristictt of t e f l o n change a b r u p t l y
a t about
45°C which i s a phase . t r a n s i t i o n p o i n t .
GAa!A-RAY INDUCED CONDUCTIVITY I N POLYETHYLENE AND TEFLO1I
UNDER HIGH DOSE RATE;
J.appl.Phys. Ü,8O4(1963)
K. Yahagi,A.lanno
I Measurements with Co ° radiation are reported fax EEJC
*KES±±EKX for conductivity as a function of dose rate,
;
temperature, and applied voltage. It is concluded that
I
above 230° K charge carriers are thermal electrons and below
i
that temperature fast electrons,
I
!
Í
i
I
Í
--••-•
72.S
.'
I
\
IRRADIATION OF POLYETHYLENE AND ELECTRICAL CONDUCTIVITY.
THE BEHAVIOR OF CARRIER TRAPS IN POLYETHYLENE UNDER
GAMMA IRRADIATIONS.
K.Yahagi,K.Shinohara
Conf.on E l . I n s u l a t i o n ( 7 í a s h i n g t o n , N a t i o n a l Acad.of S c i , ,
Natl.Res.Council,1965)Publication 1238,p.25
12.i>
20
HY^OCATIBOI: LIQUIDS
K. Yc.;iat-:i, K. O. Ke.a, J . JI. Cal d erwood
J.AWÍO . .Phys, 22,42B9(19»6)
L'o;-ir.urnrM«:Ht.?i on n-Hexane are reported. Dark conduct! vi ty
chwndftd on t.7'fifitji!erjt(f:i.í1fsrtine: und 'UctilQ n.tion)of t h ^
l i q u i d , t h o uritvo?ted liquid fiivinç a conductance of 10
r.:5-i')/cin wid th o troatcfl one a value 10 li meu lower. 1Ü£idiüti<
Co
-induced concUJoti vi t.y,ursine
íí""ma T^J!} ví^i a riu:-:
12
or 3x]O
oV/cc/aac, v/a& approxiraately the SÍUHO for "both
liouJds.This fiho-.vs t h a t till- dark current i a duo t-o i n o u r i t y
o)jnr<-e enrri f;rs,VJhile lhe photocurrant iü duo to c a r r i e r s
ororluood in the bulk of the l i o u i d T?y photoionization.
Currents shoeud the typical trnnaient 'behavior founds!
r-lso in soli'", dloleotr-ici, A theory i s dovol o;><••• a takii;^
into acc-unt r&oor.ibiiiati on and diffusion. This ^ivdfs for
tho current 1 an oxprofsyion of the forn l / l -• l/bq o +kt/'b,
v;horc q^ j f.; t h t stoso e - s t a t e spaco-charge density, k and
h HVii cons.il'Mvfcs.
ELECTRIC CHARACTERISTICS OF GAMMA-RAY IRRADIATED SHIELDING WINDOW
GLASS.
Yomomoto, K., Tsuchiya, M .
J . cpp!. Phys., 33, 3016 (1962)
Induced color and electrical resistance of shielding window glass exposed to Co°^ gamma
irradiation are investigated. A high density and a medium density glass are used, with
exposure doses between 10^ and 107 roantgen. Time-dependent currents are observed.
Resistance of medium density glass is lowered by irradiation throughout the whole doss
range; resistance of high density gloss is first lowered, reaching a minimum for 10°
roenlgen and increasing afterwards. The quantity of induced space' charge by radiation is
obtained as a current-time integral. Space charge distribution is also calculated.
(
9563
EFFECTSOT'ELECTRON IRRADIATION ON CON-
DUCTIVITY IN CdS. Yoshida, Toshio; Kitagawa, Michiharu;
EiUúm^Takahiro (Radiation Center of Osaka Prefecture, Osaka)
Appl. Phys. Lett.; 17: 337-8(15 Oct 1970).
""
Variations in radiation-induced conductivity of two different
types of CdS single crystals near liquid-nitrogen temperature
luring 5-MeV electron irradiation were investigated. The conductivity of a high-conductivily crystal is decreased, and that of
a low-conductivity crystal is increased with irradiation. Both
conductivities como nearer to each other and seem to approach a
limiting value as irradiation is continued. Two possible interpretations for the experimental result are presented, (auth)
PIÍL.I:TC:.-.LÍ;A I N
Inr Radiation M'foct;-; i n Kleotroráos.ASTf.', 3TP 3fí4(li3ó<1^
( ASTI.i o;.<0i;i:il Tonhnioa!! Publication
)
on po3t~irj-?,(H ntion conductivity , thermal
charge rol ear; o, and lu::::i.noc;c«nce are prosontor! „ '/hen
oloctron-ô rrnrUitcd fs:-!nr)los EEJEX ( i r r a d i a t i o n toapcrature
-196°C) uro hfiatod, disnhar^o c u r r e n t s are ot^orved. 'Piujy-x
sii::xtj;a*x±l:f.i.-.th»KShEi:i/i.tJí5spBya1:uvE.XHí:x«:í?O5iflv JJffacts and
threshold to;n;;«rature for i n s e t of c u r r e n t s s t r o n g l y
depend on iic-ntinf; rate,Trie s3 owor the heating- r a t e , the
3 ever the teir.ocratnrG whero e f f e c t s s t a r t . The cui-rcnts
R'DOV/ a soi-j os of peaks indic--:.tiM2 a Tipjid s t r u c t u r e for
the trapped «]ootrons»
PHHiOLiEirA ON .lEBADIAl'IHG A COAXIAL CABLE Vfl'l'H A
1
KEiri'liOli AMD GiüJ-JA FLUX
S.M.Zaiuel
i5h.Prikl.Mel-Ji.Tekh.Fiz.'Ho.3,66,Hay-June 1568
Electron and neutron i r r a d i a t i o n generates an e l e c t r i c f i e l d
mainly by p o l a r i s a t i o n . Aosur.ie a d i e l o c t i ' i c with const,
fill i n g the space between tiro conducting e l e c t r o d e s of r a d i i r . ,1-g.
The cable i s i r r a d i a t e d by gut.11.1as from one sidejuvez^age ranje of
Conpton electron» boina d.A p o s i t i v e ion remains a t c i t e irhere
an e l e c t r o n i s kknocked out by gamna i n t e r a c t i o n . On i r r a d i a t i o n
t n t h neutrons a r e c o i l proton i o hnockod out.'Piie vol.charco dens i t y i s fovind to be constant given by <J =-C,C=qJ/lTs2,where q
the abfsoluto valiic» of e l e c t r o n charco and s the range of t a n n a s ,
J t h e i r nurr.ber/crr.^,lf t!io nur.iber of absorbed y nocecsarj' to
produce 1 Conpton e l e c t r o n . a q u a t i o n s . a r e dcvelopeá f o r t o t a l
charge Q pel1 CM of cable length.A f o m u l a for the p.d# batuecn
the tiro surfaces i s derived.Charge buildup a s a function of
time i s taken i n t o account. ""
• •
73/
I
ELECTION B01ÍBARBMENT OP MOS CAPACITORS
K.H.Zaininger
Applied P h y s i c s L e t t e r s £ , 1 4 0 ( 1 9 6 6 )
732
IRRADIATION OF 1>1IS CAPACITORS WITH HIGH ENERGY ELECTRONS
K.H.Zaininger
IEEE Transactions lIuol.Sei.lTS-13,Ho.6,237(1966)
MIS capacitors consist of an n-or p-type semiconductor,covered
by a thin insulator film (often oxide) with a metal electrode
on top.Such devioes were irradiuted with 0.125 to 1 MeV electrons at 25°C.Eff©ots were investigated with C-V measurements.
C-V, and G-V curves were found to be shifted toward more negativo bias indicating the introduction of a positive charge
into the oxide and/or into interface states.Irradiation was
also performed without applied bias^for both uncovered and
metallised SÍO2 fxuuae/bove a certain fluence the effect becomes
linear and eventually saturates.The spatial location of the
,
charge was determined by stepwise removal of a layer of oxide
with a buffered SiO2 eto,thickness determined by cllipsometry.
It shows almost all positivo charge located within 100 A 0 of the
SÍO2-SÍ interface which is the region from which radiation-excited electrons can escape even in the absence of an applied
bias.Situation was different for irradiation under biasjdepending oa bias polarity.Dry oxides generate a higher density
I of positive charge than steam(or anodic)oxides.Successive \
Í bombardments changed little.Annealing of the charges,which at
room temperature are very stable,takes places between 150°C
and 300°C. Radiation annealing of previously saas^ss. positively biased and iiradiated samples takes also place. It
is believed that the radiation-generated holes diffuse in the
insulator and recombine with oleetrons,but many are captured
into stationary states,giving rise to the observed positive
charge.Holes that are neither trapped nor recorabineare neutralized at the metal or the Si.Predominant trapping of holes
has also been observed (for SÍO2) in electron-spin resonance
studies of gamma-irradiated silica,during photo-injection
of holes and electrons into SÍO2 films,and during anodic
oxidation of silicon.If no electric field is present,during
irradiation,the major effect will be electron-hole recombination,only a relatively snail number of holes being trapped
a,dd little change being induced.In a bias-bombardment experiment, electrons will readily move out of the insulator under
the filed and hole trapping Í B enhanced.
207
49979
POLARIZATION IN MICAS AND Till', INFLUENCE OF
0 IRRADIATION ON IT. Knviulovsknya, K. K.; Chcrnyshev, V. A.;
Gol'd, R. M.i Podplelnov, V. I. (Tomsk Polytechnic Insl., USSR).
lzv. Vyssh. Urheb. Siaved., Flz.j No. 1, 127-30(11)71). (In Russlan).
High-voltage polurlzallon In micas was ptudlerl, together with
the effect of 0 radiation on such phoromena. Construction of the
apparatus permitted measurements to be made In a vacuum and
over the temperature range 20 to 1100T-. The source of/! particlea WHS an electrostatic generator operating at 1 MeV and I
MA. Samples Included museovite, biotlte, and phlogoptte. It was
noted that the emf of high-voltage polarization in micas was quite
significant up to 1000'C, a factor to be considered in dc conductivity measurements. Under the Influence of 0 radiation, water
was evolved from the mica crystals as a result of radiolysis,
and molecular bonds were strengthened. This accounted for a
decrease in the emf maximum of high-voltage polarization in the
temperature range 850 to 900'C. (K.S.W.)
•
-y V /,
'«/
\
;
i
•
!
]
j
I
1
;
5605
LIGHT AND CURRENT PULSES FROM X-RAYED
POTASSIUM DI-HYDROGEN PHOSPHATE CRYSTALS. Zerem,
J. Z.; Halpcrln. A. (Hebrew Univ., Jerusalem). J. Appl.
Phys.: 42: No. 13, 5263-6(Dec 1971).
Short-duration light pulses accompanied by current pulses were
observed on warming KDP crystals x-ray irradiated at 77°K. The
pulses start a few degrees above the transition temperature (Tc =
123°K) and continue until about 200°K. The pulses appear only
under ambient gas pressures above about 0.1 torr. Warming of
the irradtated crystal to an Intermediate temperature between T c
and 200°K causes only a partial exhaustion of the pulses, and after
cooling and reheating pulses appear only above the temperature
reached In the former cycle. The pulses originate from discharges
into the surrounding atmosphere. A simple model is given to account for the experimental results, (auth)
~J 5 r *
I O t>
\
EFFECTS OP IONIZING RADIATION OS DIELECTRIC LOSSES
IV.K.Zhuravlev
-
JlBV.Vyssikh.Uchebn. Zavedenii,Fiz.!Io.5,86(1964)
Effects of low ihtensity radiation on reversible polarization
processes were studied. Both increasea and decreases of
relaxation and loss were observed.
13o