UV metal-semiconductor-metal detectors
J.-L. Reverchon, M. Mosca
N. Grandjean, F. Omnès, F. Semond, J.-Y. Duboz
CRHEA-CNRS, rue Bernard Gregory, Sophia Antipolis
06560 Valbonne, France
DCO - 10/04/00
L. Hirsch
1
IXL-CNRS-ENSEIRB, University of Bordeaux I
33405 Talence, France
THALES Research & Technology
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They cannot be reproduced, disclosed or used without THALES' prior written approval. ©THALES 2003. Template trtco V 6.0.0
Thales Corporate Research Laboratory
91404 Orsay Cedex, France
Specifications for UV detection
Combustion optimization
Medical: UVA / UVB control
Air contamination control
Fire / Flame detection
Solar blind missile launching detection (λ<300nm)
DCO - 10/04/00
Specifications
2
Dark current: as small as possible
Low noise: smallest (avoid 1/f)
Spectral selectivity: huge rejection
Responsivity: as large as possible
Linearity: photocurrent proportional to incident power
Time response: reasonably fast, 50Hz
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Applications
AlGaN for UV detection
Physical properties
=> UV detection
Difficulties with AlGaN
Difficulties for n and p doping with high aluminum contents
Almost no GaN substrate
=>Lattice and thermal expansion mismatches
DCO - 10/04/00
=>Strain, dislocations, defects…
3
=>Traps, recombination centers
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AlGaN is a III-V direct band gap semiconductor
Band gap from 3.43 eV (GaN) to 6.2 eV (AlN)
Metal-semiconductor-metal detectors characteristics
Photoconductors: large responsivity : R ~ µτlife
Photovoltaic detectors: (p.i.n., Schottky diodes, MSM)
Small responsivity (η < 1)
DCO - 10/04/00
But low noise => High
4
detectivity
p.i.n.: p doping of AlGaN difficult
Schottky diodes
MSM detectors => this study
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large mobility, controlled lifetime ?
=> Detectivity limited by 1/ f noise (I2/f), large Idark
Structures for MSM detectors
block
∆V
Photovoltaic detectors
Efficiency < 1 ⇒ responsivity < 0.23 A/W @286 nm
Schottky contacts ⇒ Idark limited
DCO - 10/04/00
Short time response: transit time
5
Lower parasitic effects on responsivity
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hν
Table of contents
•Material growth
Choice of nucleation layer
MBE grown samples
Band gap versus stress and Al content
Samples grown on Al2O3
Activity of cracks
DCO - 10/04/00
Band edge absorption broadening
6
•Transport properties
•Technological optimization
•Performances
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Samples structure for UV detection
MOCVD grown samples
Samples structures for UV detection
Thick Al.3Ga.7N layer on Al2O3
Al2O3
•Thick layer => less dislocations
Idark< 10 pA @ 100 V
-1
10
-2
10
-3
10
-4
10
-5
100V
10V
3.0
DCO - 10/04/00
•Rejection rate: 5 decades
7
•No surface effect
But front side illumination !
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3.5
4.0
Energy (eV)
4.5
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Responsivity (A/W)
Al.3Ga.7N 1.2µm
10
Samples structures for UV detection
Al.3Ga.7N / Al.4Ga.6N on Al2O3
1
Al.4Ga.6N
Active layer
Al.3Ga.7N 0.35µm
Window layer
Al.4Ga.6N 1 µm
Al2O3
Transmission (a.u.)
6
4
2
0.1
6
4
2
0.01
Al.3Ga.7N
+ Al.4Ga.6N
6
4.0
•Rejection rate: 5 decades
DCO - 10/04/00
•Back side illumination
8
(Readout circuit on front side)
Band gap has to be adjusted
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Responsivity (A/W)
•Low dislocation density
10
-1
10
-2
10
-3
10
-4
10
-5
4.1
4.2
4.3
Energy (eV)
4.4
Back
Front
Bias 15V
3.0
3.5
4.0
Energy (eV)
4.5
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Read Out Integrated Circuit
Band gap measured by
reflectivity or transmission
(α= 3x104 cm-1)
6.2
6.0
5.8
5.6
5.4
5.2
5.0
4.8
4.6
4.4
4.2
4.0
3.8
3.6
3.4
300 K
3.44+1.633x+1.09x2
but bowing=0.66 if AlN excluded
0
10
20
30
40
50
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% Al
9
For 286 nm (solar blind)
=> 42% in active layer
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60
70
80
90 100
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Sample grown by:
MBE
MOCVD
Gap energy (eV)
Band gap versus Al content
AlGaN 45% 0.3 µm
AlGaN 45% 0.3 µm
AlGaN 45% 0.3 µm
AlGaN 55% 1µm
AlGaN 60% 1 µm
AlGaN 65% 1 µm
sapphire
sapphire
sapphire
Band gap of active layer increases
with Al content in window layer
DCO - 10/04/00
Active layer compressed by window layer
10
deformation potential of 9.5 eV
Longueur d'onde AlGaN (nm)
279
278
277
276
275
274
273
54
56
58
60
62
64
Composition fenêtre xAl (%)
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66
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Effects of strain on band gap
Samples grown by MOCVD
GaN buffer layer
Growth chamber Aixtron low pressure AIX200 RF
V/III ratio: between 2000 and 3100
NH3 flux: 2l/min; Total flux: 5l/min
P = 20 mbar
(Low to avoid parasitic reaction between NH3 and TMAl)
TAlGaN= 1180 °C
Growth rate: 1 µm/h (Al.65Ga 35N); 1.8 µm/h (Al.5Ga 5N)
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Choice of nucleation layer: GaN or AlN ?
11
F. Omnes, J. of Appl. Phys. 86, 5286 (1999)
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Conditions:
Samples grown by MOCVD
Choice of buffer layer: GaN buffer layer
0.6
0.4
0.2
X593 : GaN buffer
X584 : AlN buffer
X583 : AlN buffer
Transmission
AlN buffer layer
0.0
200
DCO - 10/04/00
•T=890°C, 10 nm
•no deep levels
•no sub band gap
absorption
12
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400
600
Wave length (nm)
800
GaN buffer layer
•T=525°C, 25 nm
•deep levels in AlGaN
⇓
Non ideal features
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Transmission
0.8
Effects of deep levels in AlGaN
Non ideal effects 1
Tunneling
+
hν
+
DCO - 10/04/00
Parasitic effects of
traps
13
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Tunneling in contacts
Sub-band gap response
Persistent photoconduction
Non linearity
Long non exponential response transient
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∆V
Sub band gap
response
Effects of deep levels in AlGaN
Non ideal effects 2
3
10
MOCVD
buffer GaN
80 Hz, 2 V
80 Hz, 20 V
0 Hz, 20 V
2
10
1
10
0
10
10
-1
10
-2
0.32
0.36
Wavelength(µm)
DCO - 10/04/00
0.28
14
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0.40
0
10
10
-1
10
-2
10
-3
10
-4
MOCVD
buffer GaN
80 Hz
30 V
1V
0.28
0.32
0.36
Wavelength (µm)
0.40
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Responsivity (A/W)
4
10
Normalized responsivity (u.a.)
Spectral responsivity change with voltage and
chopper frequency
Samples grown by MOCVD
Choice of buffer layer: AlN buffer layer
DCO - 10/04/00
15
10
-2
10
-3
10
-4
10
-5
10
-6
MOCVD / X584
Buffer AlN
5V
0 Hz
8 Hz
80 Hz
190 Hz
0.28
0.32
0.36
Wavelength (µm)
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0.40
Responsivity (A/W)
Responsvity (A/W)
•Spectral responsivity constant with chopper frequency
•Dynamics: 4 / 5 orders of magnitude
10
-2
10
-3
10
-4
10
-5
10
-6
MOCVD X584
finger width 2 µm
spacing 4 µm
80 Hz
0.28
0.32
0.36
Wavelength (µm)
20 V
10 V
5V
2V
0.40
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AlN buffer layer (T=890°C, 10 nm)
=> No deep levels in AlGaN
Samples grown by MBE
1
Sample grown by MBE on sapphire
2
0.1
0.01
4
2
Buffer AlN
Buffer GaN
DCO - 10/04/00
4
GaN or AlN buffer layer ?
3.2
3.6
4.0
Energie (eV)
AlN: Transparent to UV (6.2eV)
Less known / bad electrical properties
GaN: small band edge absorption @ 3.4 eV ?
16
4.4
GaN chosen for MBE
N. Grandjean, J. Appl. Phys. 83, 1379 (1998)
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Transmission
RIBER chamber
NH3 as N source
Tgrowth = 800°C / 850°C
4
Increasing Al content…
AlGaN layer grown at 850°C by MBE
AlGaN 45% 0.3µm
AlGaN 45% 0.3µm
AlGaN 45% 0.3µm
AlGaN 45% 0.3µm
AlGaN 65% 0.8µm
AlGaN 55% 1µm
AlGaN 60% 1µm
AlGaN 65% 1µm
AlN 0.3µm
saphir
saphir
saphir
DCO - 10/04/00
More cracks with increasing Al content
Strain relaxation
17
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saphir
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AlGaN 55% 0.2µm
Increasing Al content…
Cracks and dark current
18
•No crack:
•1 shallow crack:
•1 deep crack:
•more cracks:
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~10 pA @ 30 V
~10 pA @ 30 V
Idark>100 pA @ 30 V
Idark>100 pA @ 30 V
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DCO - 10/04/00
Cracks
Increasing Al content…
•Insertion of a 100 nm AlN buffer
(compression of window layer)
•Lower growth temperature: 800°C
(thermal expansion difference reduced)
•Reduced thickness of the window layer: 0.85 µm
(total elastic energy reduced)
AlGaN (45%) 0.4 µm
[Tg=800°C]
AlGaN (65%)
1 µm
NO CRACKS
DCO - 10/04/00
AlN 100 nm
19
GaN 25 nm
Sapphire c
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F. Natali, Appl. Phys. Lett. 82, 499 (2003)
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AlGaN layer grown at 800°C by MBE
Band edge absorption broadening
Ultimate band edge absorption
broadening in AlGaN ?
0.8
0.6
0.4
Main reason: Alloy fluctuations
0.2
0.0
4.00 4.05 4.10 4.15 4.20 4.25
DCO - 10/04/00
Energie (eV)
20
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Attention : active layer thickness
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Absorption (u.a.)
1.0
Band edge absorption broadening
Statistical fluctuations in AlxGa1-xN
N III elements in excitonic volume Vexc
Probability to find n Al among N:
p ( n ) = C x (1 − x )
n
N
a
N −n
Low excitonic distance in AlxGa1-xN :
libre
exc
r
=
ε
mr m0
rexcitAlN ~ 1.5 nm
DCO - 10/04/00
rexcitGaN ~ 3 nm ⇒
21
aB
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h
rexcitonique
e-
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N
Ga
Al
Band edge absorption broadening
Schubert, PRB (1984)
Baranowski, SPS (1978)
100
Experiment
Model
80
60
40
20
0
0
80
20
40
60
80
Aluminum content(%)
100
60
40
20
AlxGa1-xN
0
0.0
0.2
0.4
0.6
0.8
Composition
DCO - 10/04/00
Plus LO phonon @ 300 K : σ=[502+252]1/2=56 meV
22
Broadening close to statistical fluctuations
for solar blind
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1.0
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120
50 meV @ 45%
Bandgap broadening (meV)
Band gap broadening (meV)
40 meV @ 45%
Alloy fluctuations and spectral response
4
T40% ~ e
2
Active layer
2
Band gap distribution
A30% ~ 1 − e
Al.3Ga.7N
/ Al.4Ga.6N
4.1 4.2 4.3
Energy (eV)
1.0
0.8
0.6
0.2
0.1
4.0
4.1
4.2
4.3
4.4
Energy (eV)
0.2
0.0
3.9
Simulation
Experiment
0.3
0.0
3.9
Al.3Ga.7N
0.4
0.4
4.4
−α hν − E30% d30%
Al.4Ga.6N
4.0
4.1
4.2
4.3
Energy (eV)
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4.4
Absorption spectra modeled with
band gap fluctuations
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4
4.0
DCO - 10/04/00
−α hν − E40% d 40%
0.1
0.01
23
Window layer
Al.4Ga.6N
Response (u.a.)
Transmission
1
Band edge absorption broadening
Active layer thickness
100
A = (1 − e −α d )
α= 3.10-4 cm-1
=> active layer: 0.4 µm
(plus contribution of back reflection
on metal contact)
Sigma=50 meV
Eg0=4eV
α(gap)=3e.10cm-1
T 10-1
10-2
d=1 µm
-3
10-3
3.8
4
Energy (eV)
1
1
d=1
DCO - 10/04/00
T
24
d=1
T
0.5
0.5
d=0.1
0
4
4.2
4.5
Energy
42 % / 62 %
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d=0.1
5
0
4
4.5 Energy
42 % / 57 %
5
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Sharpness of cutoff
increases with thickness d:
d=0.1 µm
Table of contents
Sub micronic MSM by E-beam lithography
IBICC measurements
Electrode Characteristics
DCO - 10/04/00
•Technological optimization
•Performances
25
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•Material growth
•Transport properties
Heterostructures on Si(111) substrate
10
-1
10
-2
10
-3
10
-4
10
-5
Al.5Ga.5N / AlN / GaN / AlN / Si(111)
C(V) measurements
=> 2DEG (AlN / GaN)
Capacitive coupling of GaN
=>transitory only with AC flux
3.2
3.4
3.6
3.8
4.0
Energy (eV)
E
DCO - 10/04/00
∂E
I =ε
∂t
26
Buffer
AlN
Pt /Au
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AlGaN
AlN GaN
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Responsivity (A/W)
Problem of capacitive coupling
Sub-micronic MSM by E-beam lithography
Geometrical effects
2 µm
0.6 µm
Reduce Finger area
=> Reduced capacity
DCO - 10/04/00
Reduce Finger spacing:
Reduce bias for a same polarization
Electric field confined in AlGaN
27
2D solver :Altlas-Silvaco
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Advantages of sub-micronic MSM
E beam lithography: 0.4-1 µm
J.Y. Duboz, J. Appl. Phys. 92 5602 (2002)
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Sub-micronic MSM by E-beam lithography
Response and dynamic
0.35
Response (A/W)
0.30
.6µm
2µm
.6µm simul.
2µm simul.
0.25
0.20
0.15
0.10
0.05
DCO - 10/04/00
0.00
28
0
20
40
Voltage (V)
60
10
-2
10
-3
10
-4
10
-5
10
-6
2µm, 20V
.6µm, 15V
3.2
3.6
4.0
4.4
Energie (eV)
4.8
High response at lower voltage
Simulation: R~V0.7 (collection if Field>Eloc/Ldiff)
Rejection rate > 5 decades
Responsivity: 0.044 A/W @ 40V => η=20%
J.Y. Duboz, J. Appl. Phys. 92 5602 (2002)
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Responsivity (A/W)
Al.45Ga.55N / AlN / GaN
/ AlN / Si(111)
IBICC measurements
Anode
Cathode
IBICC 4He+ 2MeV
=> 1µm² spot size
Anode
Cathode
(a)
(b)
DCO - 10/04/00
40 µm
29
40 µm
L. Hirsch, J. Appl. Phys. .91 6095 (2002)
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Al.45Ga.55N / AlN / GaN
/ AlN / Si(111)
IBICC measurements
Atlas-Silvaco: Field electric
@ 0, 25, 50 and 75 V
∆V
Charge (10
-15
C)
20
15
75
60
50
40
30
V
V
V
V
V
10
DCO - 10/04/00
Cathode
30
Anode
5
Attenuation length ~ 5 µm
0
5
10
15
20
25
30
d (µm)
Electron-hole better collected at
cathode than anode
L. Hirsch, J. Appl. Phys. .91 6095 (2002)
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4He+
Metal Semiconductor Metal detectors
MOCVD: X584
AlGaN (50%)
0.4 µm
AlGaN (65%)
0.85 µm
AlN 100 nm
Sapphire
-6
2.5x10
2.0
1.5
1.0
90 µm
40 µm
25 µm
20 µm
0.5
0
5
10
15
20
15 µm
10 µm
5 µm
2 µm
25
Voltage (V)
DCO - 10/04/00
Saturation at V > 15 V
Photo response increases with fingers width
31
Width from 2 to 90 µm / Spacing constant: 4 µm
Metal must cover a surface as large as possible
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30
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-2
Photocurrent density (A/cm )
Response and electrodes area
Metal Semiconductor Metal detectors
Inter-digitized fingers spacing
2500
AlGaN (45%) 0.4 µm
AlGaN (65%)
1 µm
AlN 100 nm
MSM MBE
1-level detectors
80 Hz - 270 nm
2000
1500
1000
width 5 µm - spacing 4 µm
width 5 µm - spacing 10 µm
500
width 2 µm - spacing 4 µm
width 2 µm - spacing 10 µm
GaN 25 nm
0
Sapphire c
5
10
15
20
bias voltage (V)
25
30
DCO - 10/04/00
Saturation at V > 10 V: all carriers collected
32
Photocurrent increases with electrodes area
and decreases with finger spacing
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photocurrent (pA)
MBE: N695
•Material growth
•Transport properties
•Technological optimization
Metal deposition
Choice of dielectric
Geometrical optimization
•Performance
33
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DCO - 10/04/00
Table of contents
Metal Semiconductor Metal detectors
Schottky contact
2.0
Schottky barrier (eV)
1.8
1.6
DCO - 10/04/00
1.4
34
•Processing
Clean HCl 1’ + rinse 4’
Evaporation of Pt / Au
(100 Å / 1000 Å)
Annealing at 400°C 10’
(mechanical adherence)
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1.2
1.0
0
10
20
30
Aluminum content (%)
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•High value for Schottky barrier
⇓
Advantage for low Idark
Metal Semiconductor Metal detectors
Two level process 1
2-level metallization
Spacing: 2-10 µm
Finger width: 2-5 µm
metal
dielectric
Active area:
100 µm ×100 µm
DCO - 10/04/00
Contact
pads
35
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Contact
reporting
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AlGaN
Metal Semiconductor Metal detectors
Two level process 2
• SiO2 (300 nm) PECVD 300°C
• BCB (1500 nm)
dark current (nA)
(spin-coated and annealed in vacuum at 250°C for 30 min)
10
5
10 3
10
finger width 5 µm
spacing 8 µm
dielectric: SiO2
1-level
2-levels
1
-1
10
-3
DCO - 10/04/00
10
36
-30
-20
-10
0
10
bias voltage (V)
20
30
M. Mosca, MRS proceeding (2003)
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They cannot be reproduced, disclosed or used without THALES' prior written approval. ©THALES 2003. Template trtco V 6.0.0
• Si3N4 (300 nm) PECVD 300°C
Metal Semiconductor Metal detectors
Dielectric optimization
no dielectric
SiO2
Si3N4
BCB
10
0
N695
100x100 µm²
finger width 2 µm
spacing 4 µm
-10
-20
-20
-10
0
Bias voltage (V)
10
DCO - 10/04/00
1-level detector: 15 fA at –10 V!
2-levels detectors:
37
Currents in fA range up to 13 V (Si3N4) and 15.5 V (SiO2)!!!
Except BCB (Modification of AlGaN surface, dielectric stress)
M. Mosca, MRS proceeding (2003)
THALES Research & Technology
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Dark current (fA)
20
Metal Semiconductor Metal detectors
Dark current and perimeter
Dark current increases with perimeter
If dark current can be measured !
Idark(µA)
1200
800
Idark 30V
Idark 15V
400
400
600
800
1000 1200
DCO - 10/04/00
Perimeter (µm)
38
•Low dark current
•High responsivity
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=> low number of fingers
=> low spacing / large fingers
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1600
Metal Semiconductor Metal detectors
10
-1
10
-2
10
-3
10
-4
10
-5
X584
finger width 2 µm
spacing 4 µm
0 Hz - 20 V
DCO - 10/04/00
@ lower bias:
•Charges not efficiently
collected from pads
•1-level ~ 2-level
39
responsivity (A/W)
0.28
10
-2
10
-3
10
-4
10
-5
10
-6
0.32
X584
finger width 2 µm
spacing 4 µm
0 Hz - 2 V
0.28
SiO2
BCB
Si3N4
no dielectric
0.36
0.40
SiO2
BCB
Si3N4
no dielectric
0.32
0.36
wavelength (µm)
0.40
M. Mosca, MRS proceeding (2003)
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responsivity (A/W)
Contribution of contact pads in the 1-level detector
•Material growth
•Transport properties
•Technological optimization
•Performances
Dark current
Detectivity
Time response
Comparisons with Schottky photodiodes
40
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DCO - 10/04/00
Table of contents
Performances
Dark current
0
X584
no dielectric
-20
-30
finger width 2 µm
spacing 4 µm
N695
no dielectric
N695 - SiO2
-40
-40
-30
-20
bias voltage (V)
-10
0
DCO - 10/04/00
Very high quality of samples:
Dark current in fA range up to –35 V!!!
41
M. Mosca, MRS proceeding (2003)
THALES Research & Technology
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dark current (fA)
-10
Performances
Dynamic
No crack with different techniques of growth
MBE: N695
AlGaN (50%)
0.4 µm
AlGaN (65%)
0.85 µm
AlN 100 nm
10
-2
10
-3
10
-4
10
-5
42
finger width 2 µm
spacing 4 µm
0 Hz
X584 / MOCVD
N695 / MBE
AlGaN (45%)
0.4 µm
AlGaN (65%)
1 µm
AlN 100 nm
GaN 25 nm
DCO - 10/04/00
Sapphire
Responsivity (A/W)
MOCVD: X584
Sapphire
0.28
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0.32
0.36
Wavelength (µm)
0.40
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Responsivity ~ 0.06 A/W (η=25 %)
Performances
Noise & Detectivity
V>20V:
1/2
Idark > 10pA
1/f noise filtered by capacitive
coupling (2DEG and AlGaN)
=> 1/fγ with γ>1
PSD= βI²/f with
Ln (Noise(A/Hz ))
-26
β=5.10-5
-28
-30
-32
-34
DCO - 10/04/00
-2
43
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1.39
-50V 1/f
1.2
-80V 1/f
1.2
-100V 1/f
-1
0
1
2
Ln(Frequency (Hz))
3
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Al.5Ga.5N / AlN / GaN /
AlN / Si(111)
Performances
10
-10
10
-11
10
-12
10
-13
10
-14
0.12
Detectivity (Hz /W)
1/2
DCO - 10/04/00
10
44
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Idark
Noise 2kHz
Response
0.10
0.08
0.06
0.04
0.02
0
PSD=2eI+βI²/f with β=5.10-5
NEP=0.3 pW at 50 Hz
0.16
0.14
-9
20
40
60
Bias (V)
80
100
6
4
2
12
6
4
0
20
40
Bias (V)
60
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1/2
V<20V:
Noise < measurement limit
Noise extrapolated using
10
Responsivity (A/W)
Al.5Ga.5N / AlN / GaN /
AlN / Si(111)
Noise(A/Hz ) et Idark (A)
Noise & detectivity
Performances
Estimation of noise & detectivity at very low current
Johnson noise 4kT/R:
I²/f Noise βI²/f with β=5 × 10-5:
Shot noise 2eI:
~ 10-18 A/Hz1/2
~ 10-17 A/Hz1/2
~ 2.10-17 A/Hz1/2
Response: 0.05 A/W
DCO - 10/04/00
Detectivity: 4 × 1014 W-1 @ 100 Hz / NEP = 2.5 fW
45
500 photons / second / pixel (100 x100 µm²)
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Samples with Idark~1 fA @10 V
Noise < measurements capability
Performances
Response time / linearity
=>Response time < 1 ms
(chopper limited)
=>No deep levels
10
-2
0 Hz
8 Hz
30 Hz
80 Hz
190 Hz
-3
10
-4
10
-5
N695
finger width 2 µm
spacing 4 µm
5V
0.26
0.28
0.30
0.32
0.34
wavelength (µm)
0.36
0.38
DCO - 10/04/00
•Linearity on several
orders of magnitude
46
still to verify @ low flux
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Photocurrent (a.u.)
4
2
1
4
2
0.1
4
2
2
4
2
4
1
10
100
Optical flux (a.u.)
0.40
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Response is not a function of
chopper frequency
responsivity (A/W)
•Response time
10
Performances
Comparisons with Schottky photodiodes
MBE
/ MSM
MBE
/ Schottky
MOCVD / MSM
MOCVD / MSM
MOCVD / Schottky
0.01
0.001
0.0001
DCO - 10/04/00
MBE
/ MSM
MBE
/ Schottky
MOCVD / MSM
MOCVD / MSM
MOCVD / Schottky
0.4
0.2
0.0
200
47
0.6
300
400
500
600
Wave length (nm)
700
800
200
300
400
500
600
Wave length (nm)
Schottky vs MSM:
Equivalent for sub band gap / dynamics
Responsivity ?
Dark current with bias ?
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700
800
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0.1
Transmission
Transmission
0.8
Conclusion
Al content adapted to UV solar blind detection
MSM with very low Idark:
fA regime up to 35 V
Huge spectral selectivity:
5 orders of magnitude UV / visible
Huge detectivity: up to 4 × 1014 W-1 @ 100 Hz
DCO - 10/04/00
Key point: Readout Integrated Circuits
48
Low flux and currents
10 V for bias
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From 200 to 300 nm
Acknowledgment
One author (MM) wishes to acknowledge financial support
from a Curie Research Grant (G5TR-CT-2001-00064)
DCO - 10/04/00
ONERA (France) for technical support
49
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This document and any data included are the property of THALES.
They cannot be reproduced, disclosed or used without THALES' prior written approval. ©THALES 2003. Template trtco V 6.0.0
Work partially supported by DGA (contract N° 00-34-068)