CVD Diamond based Active Devices
Viareggio – CAEN June 24th, 2011
Paolo Calvani
S2DEL
DiaC2Lab
S2DEL
(Diamond & Carbon Compounds Lab)
Solid State and Diamond Electronics Lab
IMIP - CNR - Montelibretti (RM)
Università degli Studi “Roma Tre”
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Viareggio – CAEN June 24th, 2011
Daniele M. Trucchi
Paolo Calvani
Alessandro Bellucci
Emilia Cappelli
Stefano Orlando
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
CNR-IMIP: Know-How & Projects
1989-1995
Study of Nucleation and Growth Mechanisms of CVD Diamond
Mechanical Applications
1995-1999
CVD Diamond protective coatings of cutting tools
Coordination of MURST-CNR 5% Project
2003-2006 Development of high-tech materials and ceramic coatings
ENEA-MIUR “PROMOMAT” Strategic Project
Viareggio – CAEN June 24th, 2011
Electronic Applications
1999-2001
Secondary electron emission amplifiers for scanning electron microscopy
MADESS II Applied Research Project
2000-2002 VUV & DUV Radiation Detectors in collaboration with S2DEL – Univ. Roma Tre
ASI ARS1/R07/01 Aerospace Project
2001-2005 Poly-Diamond Radiation Dosimeters for Radiation Therapy
Coordination of European Project “DIAMOND” G5RD-CT01-00603
2003-2007 Nanostructured Carbon and graphene Structures for Opto-Electronic applications
FIRB Project “Micro & Nanocarbon” & FISR Project “High Density Memories”
2008-2010 Systems for direct nuclear-to-electric energy conversion
Coordination of CNR-RSTL “ECO-Diamond” Project
2008-today Development of Single-Crystal Diamond dosimeters in collaboration
with S2DEL - Univ. Roma Tre
2010-2013
Thermionic-thermoelectric conversion module for solar concentrated systems
E2PHEST2US Project
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
CNR-IMIP: Facilities
Material
Production
Viareggio – CAEN June 24th, 2011
~
Hot Filament
CVD for diamond film
deposition
Characterization of
Chemical-Physical
Properties
Spectroscopy
Technological
Processes for
Device
Fabrication
Raman & IR
MW-CVD for
surface hydrogen
termination
Microwave CVD for
diamond (doped)
film deposition
Characterization of Device
Performance
Vacuum & Temperature
Electronic Characterization
(VTEC) (10-9 Torr, T=771200 K) for Thermionic
Emission
Secondary
Electron Emission
Characterization
Setup
X-Ray
Photoconductivity
Setup
Spectral (UV-VisNIR)
Photoconductivity
Setup
Spectral Photometry
Microscopy
RF Sputtering for
deposition of metals
Ti, Al, Cr, …
SEM & EDS
Pulsed laser (Excimer
& Nd:YAG) ablation
for (nanostructured)
thin-film deposition
of carbon, carbides,
refractory metals
Four-Point Probe
under vacuum,
T=25-400 °C
AFM
Seebeck Effect
Measurement System for
Thermoelectric
Characterization
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Diamond Electronic Properties
Band gap
Thermal
conductivity
Breakdown
electric field
Eb
Mobility
Carriers sat.
velocity vsat
Dielectric
constant
εr
eV
W/cmK
106 V/cm
cm2/Vs
107 cm/s
-
Diamond
5.5
20
10
2000 - h
1.0
5.7
Gallium nitride
3.4
1.5
2.5
2000
2.5
8.9
Silicon carbide
3.27
4.9
3.0
1000
2.0
9.7
Gallium Arsenide
1.42
0.55
0.4
8500
1.29
12.9
Silicon
1.12
1.5
0.3
1400
1.0
11.8
Germanium
0.67
0.58
0.1
3900
1.0
16.2
Viareggio – CAEN June 24th, 2011
Material
 High Frequency – High Power Field Effect Transistors
 UV Power Switches
 Renewable Energies Conversion Stages
5
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
High Frequency – High Power
Field Effect Transistors
S2DEL
Viareggio – CAEN June 24th, 2011
Plasma assisted Hydrogen termination of CVD Diamond induces p-type conductive channel
Evolution of the band bending, activated by air exposure,
during the electron transfer process at the interface
between diamond and water layer[b]: density-of-states
(DOS) is changing from 3D to 2D: 2DHG
Fabricated by S2DEL and IFN-CNR
6
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
RF Power Characterization by
Politecnico di Torino
CLASS A @ 2GHz
Pout=0.2 W/mm
Gain=8 dB
PAE=21.3%
S2DEL
Viareggio – CAEN June 24th, 2011
Pout @ 1GHz ~ 0.8 W/mm[a]
Best result for Polycrystalline Diamond
LG=200nm, WG=50um
VDS=-14 V, VGS=-0.3 V
fMAX = 15.2 GHz
ft = 6.2 GHz
Maximum VDS applied=80 V
Eapplied= 2 MV/cm
Channel conductance is always positive.
No self heating effects!
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Polycrystalline Diamond
PolyD4 by Russian Academy of Sciences
-20 dB/dec.
P7MS by Russian Academy of Sciences
Wg=50 μm
WG=25 μm
Gain = 15 dB@ 1 GHz
Viareggio – CAEN June 24th, 2011
Single Crystal Diamond
Gain = 22 dB @ 1 GHz
fMAX =26.3 GHz
fMAX = 23.7 GHz
fT = 6.9 GHz
LG=0.2 μm
fT = 13.2 GHz
VGS=-0.2 V, VDS=-10 V
Eapplied= 0.5 MV/cm
S2DEL
RF Small Signal Characterization in collaboration with by Tor Vergata University
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Polycrystalline Diamond PolyD4 by Russian Academy of Sciences
S2DEL
Viareggio – CAEN June 24th, 2011
-20
dB/dec.
Gain =
16 dB @1GHz
Lg=0.2 μm, Wg=25 μm
VGS=0.0 V, VDS=-35 V
fMAX = 35 GHz
fT = 10 GHz
Eapplied= 1.75 MV/cm
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Viareggio – CAEN June 24th, 2011
S2DEL
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
UV POWER SWITCHES
VDS
Lecroy WavePro 960
2 GHz 16Gs/s
digital oscilloscope
Picosecond 5550B
18 GHz Bias tee
DUT
Si diode
(for trigger)
=193 nm
50 Oscilloscope
input resistance
x
1,0
GPIB
Laser pulse shape
recorded by
vacuum
phototube
0,8
Normalized signal
Viareggio – CAEN June 24th, 2011
Neweks PSX 100 excimer laser
Filled with ArF gas mixture
S2DEL
0,6
VGS
(Keithley 617)
0,4
0,2
0,0
-5 10
-9
0
-9
5 10
-8
1 10
Time (ns)
-8
1,5 10
2 10
-8
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
12/23
Source
Drain
G
UV generated
carriers
diamond
0
VDS=-9.6 V
V =-10.0 V
GS
0
1,5 10
V =-8.6 V
GS
V =-7.0 V
GS
0
1 10
V =-5.0 V
GS
5 10
-1
V =-2.5 V
V =0.0 V
GS
GS
0
V =+1.0 V
GS
-1
-5 10
-10
0
10
Time (ns)
20
30
Drain-Source Photogenerated Voltage (V)
Drain-Source Photogenerated Voltage (V)
Viareggio – CAEN June 24th, 2011
2 10
6 10-1
VGS=-3.4 V
V =-6.0 V
5 10-1
DS
V =-5.0 V
V =-4.0 V
4 10-1
DS
DS
3 10-1
V =-3.0 V
DS
2 10-1
V =-2.5 V
DS
V =-0.5 V
DS
1 10-1
0
-1 10-1
V =-0.0 V
DS
-2 10-1
-10
0
10
Time (ns)
20
30
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
13/23
Source
Drain
G
UV generated
carriers
0,07
0,06
Peak Amplitude (V)
Viareggio – CAEN June 24th, 2011
diamond
0,05
0,04
0,03
0,02
0,01
0
-0,01
0
0,02
V
0,04
DD
(V)
0,06
0,08
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Renewable Energies Conversion Stage
Viareggio – CAEN June 24th, 2011
EU Project E2PHEST2US’
Duration: 3 years (Jan 2010 - Jan 2013)
•Total Project Cost: 2.68 M€
•Total EU Funding: 1.98 M€
Partners:
•CNR (Italy, Scientific Coordination)
•CRR (Italy, Management Coordination)
•SHAP (Italy)
•Tel Aviv University (Israel)
•Tubitak (Turkey)
•Prysmian (Multinational Industry)
•Maya (San Marino)
*For details, http://www.ephestus.eu
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
EU Project E2PHEST2US’
Thermionic Stage
Load
Radiation
Absorber
Collector
Rload
Rload
Thermoelectric
Stage Load
p
Under
Vacuum
Viareggio – CAEN June 24th, 2011
n
Concentrated
Solar
Radiation
(400 – 1000
suns)
p
n
p
n
Thermionic
Emitter
Inter-electrode
Space (<1 mm)
Development of:
T
•A radiation absorber made of ceramic materials
able to work stably at high temperature (700 1000 °C)
TR (700-1000 °C)
TE
TC (250-400 °C)
•A thermionic conversion stage with CVD diamond
as the active material
TTE
•A thermoelectric conversion stage constituted by
high Seebeck coefficient materials
TAmb
•Maximum theoretical efficiency ≈ 30%
Final Thermal
Stage
Thermoelectric
Stage
z
*For details, http://www.ephestus.eu
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
CVD Diamond based Active Devices
Viareggio – CAEN June 24th, 2011
Thanks for the attention
S2DEL
DiaC2Lab
S2DEL
(Diamond & Carbon Compounds Lab)
Solid State and Diamond Electronics Lab
IMIP - CNR - Montelibretti (RM)
Università degli Studi “Roma Tre”
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Viareggio – CAEN June 24th, 2011
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza
Alternative Technology in Concentrating Systems
•Multi-junction Photovoltaic Cells
Nominal Conversion Efficiency of 30%
Compactness
No mechanical parts in movement
Viareggio – CAEN June 24th, 2011
•Highly Expensive
•Mandatory Need of Cooling (Conversion Efficiency Exponentially
Decreases with Temperature)
•Illumination Local Inhomogeneities Causes Output Bottlenecks
•Production Dependent on Semiconductor Industry (Few Large-Scale
World Suppliers)
•Thermodynamic Conversion by Heat Engines (Stirling, Rankine)
•Nominal Conversion Efficiency of 35% at High Temperatures (> 600 °C)
•Not Compact System
•Mechanical Parts in Movement (Degradation with Operative Time)
•Economically Reasonable for Large Plants (> 10 kWe)
Elettronica basata sul Diamante: Applicazioni nella Fisica delle Alte Energie, Fisica Nucleare, Astrofisica, Fisica Medica ed Elettronica di Potenza