general atomics thermo-photovoltaic (tpv)...

1Strauch – General Atomics

Radioisotope TPV Power Systems for SpaceGeneral Atomics Technology Information - Business Sensitive

General Atomics Thermo-Photovoltaic (TPV) Power Sources

Presented By:

Jason Strauch

[email protected]

(858)-999-5239

Presented To

Nuclear and Emerging

Technologies for Space

Albuquerque, NM

Feb 23-25, 2015

Milli-Watts to 10s of Watts for 20 years

2 W Power Source


Radioisotope TPV Power Systems for Space

History and Acknowledgements

TPV Power Source Overview

Heat Source

TPV Cells

Optical System

System Performance

NASA Specific Designs

Path Forward

Overview of GA Radioisotope Power System



TPV History

TPV Technology developed over 10 year period under

Naval Reactors program: highly funded competition

between KAPL and Bettis National Labs, ~$100M from later

‘90s to early 2000s

DARPA RIMS program had first fueled TPV test, heat source

and cells decoupled, ~$1.5M from 2004 to 2006

DARPA MIPS program resulted in integrated design and

long term fueled testing, ~$3.5M from 2006 to 2012

GA IRAD scales design up to current level, with other

support, ~$1.5M from 2012 to 2014

NASA TPV programs achieve 15-19% efficiency in GPHS

electrically heated system at much larger scale, 2007-2012

History and Acknowledgments



TPV Power Source for NASA

~2x the efficiency of traditional thermoelectric RTGs

- Reduced fuel loading = lower weight

and fuel cost

Scalable from 1 mW to >50 W

- Higher efficiency than direct conversion such as

alpha or betavoltaics or chemical batteries

- Design allows varying isotope fuel loading / power

source size

20+ year life

- Proven minimal neutron TPV cell degradation

Solid State – no moving partsGA 2 We TPV battery

next to a standard D-cell

Ideal for outer planetary exploration (beyond solar)

or deep space missions.



Heat Source - Isotope Selection

Isotope candidates for 2 We/Long Life Power Source

Study of ~3000 total isotopes results in just 3 reasonable

candidates

Critical is the Specific Power and Half Life

Also important is the semiconductor lattice damage due to

neutron flux; Cm-244 used to study neutron degradation

Isotope parameters after 20 years:

PU-238 best for NASA missions

IsotopeHalf Life (Years)

Thermalpower

[W]

Specific Power (W/g)

Fuel mass[gm]

Fuel Volume[cm^3]

Eff.[%]

BatteryVolume

[cm3]

Radiation Dose

[mrem/hr]

PEOL[W]

EOL/BOLThermal Power

EOL/BOL Output

NeutronDamage

Factor

Sr-90 28.7 25.5 0.92 34.00 13.08 8 80 42,000.0 1.61 19.2% 81.5% 0.5%

Pu-238 87.7 25 0.56 63.25 12.53 8 78 1.5 1.81 6.5% 90.5% 3.2%

Am-241 432 30 0.11 365.00 33.22 6.8 140 14.9 1.92 1.3% 96.2% 2.5%



Safe Heat Source - Pellet Containment

All tests were performed cumulatively on a single sample. The standard allows 2 samples per test.

Double e-beam welded, 90Ta/10W MIPS

pellet and analysis

General Atomics has developed safe fuel pellet designs for terrestrial use at 2 scales

Passed tests include, among others: 800C for > 30 min 1000 kg crush test 500C at 13,800 psi internal

pressure (33 yr battery operation equivalent at 627C)

70 MPa external pressure

Temperature cycling: -40C (20 min) to 600C (1 h) and thermal shock 600C to 20C

The 2 We/ 20 year pellet

will be encapsulated to

meet safety standards

by LANL and tested by

arc-jet at NASA Ames

LANL-GA designed 20 W Heat

Source Pellet

Potential heat source design using NASA GPHS have been developed

For DARPA MIPS a pellet design has been developed to pass ANSI class 5,

49 CFR173.469 and Pacemaker Interim Guidance standards



Four Critical Areas are Needed for Successful Device Development

TPV Design

Epitaxial Growth

Cell Processing1.Back Contact Etch

2.Isolation Etch

3.Dielectric Etch

4.Metallization

Electrical

Testing

With shunting defects

Without shunting defects

Defect density

= 9E4 / cm2

Defect density

< 100 / cm2

TPV Devices Fabrication

TPV cells are difficult to make and the capability exists at GA

1 2

3 4



0

5

10

15

20

25

30

600 800 1000 1200 1400 1600 1800

De

vic

e E

ffic

ien

cy

Hot-Side Temperature (K)

Eg=0.50 eV

Eg=0.55 eV

Eg=0.60 eV

Eg=0.65 eV

Eg=0.70 eV

Optimization of TPV Cells Power Conversion

InGaAs TPV devices are the best for

NASA applications

Bandgap at 0.6 eV (2.07 micron)

has highest conversion efficiency

for ~1000 K

Produce 0.25 to 1 W/cm2 at >20%

device efficiency

0

0.5

1

1.5

2

2.5

300 500 700 900 1100 1300 1500 1700 1900 2100 2300 2500Wavelength (nm)

Irra

dia

nce, W

/m2-n

m..

.

0

20

40

60

80

100

120

140

160

180

Irra

dia

nce, W

/m2-n

m..

.

Increasing Energy of Photons

InGaP

GaAsSi

GeInGaAs

1050K

Blackbody

Solar

Space

Solar

Earth

0.3 0.5 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5Wavelength (microns)

Band edge of

convertible

photons for

different PV

material

systems

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

1000 1100 1200 1300 1400 1500 1600

Po

we

r D

en

sit

y (W

/cm

2)

Hot-Side Temperature (K)

Eg=0.50 eV

Eg=0.55 eV

Eg=0.60 eV

Eg=0.65 eV

Eg=0.70 eV

Eg=0.74 eV

InGaAs TPV Cell Power Density Best across wide range of temperatures

InGaAs TPV Cell Efficiency best overall

Conversion range



TPV Cells – Tunable Voltage and Load Matching

TOP FIELD

EMITTER

BASE

BACK FIELD

INSULATING SUBSTRATE

Back

Surface

Reflector

Insulating

InP

Substrate

- Busbar

(device

contact)

InGaAs/InP MIM Structure (not to scale)

Epitaxial

MIM

Structure

Dielectric

insulator

AR

coating

+ Busbar

(device

contact)

Cell

interconnects

TOP FIELD

EMITTER

BASE

BACK FIELD


TOP FIELD

EMITTER

BASE

BACK FIELD


Back

Surface

Reflector

Insulating

InP

Substrate

- Busbar

(device

contact)

InGaAs/InP MIM Structure (not to scale)

Epitaxial

MIM

Structure

Dielectric

insulator

AR

coating

+ Busbar

(device

contact)

Cell

interconnects

Monolithically Integrated Module (MIM)

TPV cell voltage can be tailored for

specific applications

Diodes are series-connected on-chip

Reduced I2R (resistive) losses

Same power source can deliver multiple

voltages, for instance 12 V and 24 V from a

single power source

0

5

10

15

20

25

30

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6

Forward Voltage (V)O

utp

ut C

urr

ent (m

A)

0

5

10

15

20

25

Outp

ut P

ow

er

(mW

)

himp = 99.0%

himp = 99.9%

4 junction TPV cell

@ Temit = 1100K

2 junction TPV cell

@ Temit = 900K

50 W load line

6-Junction MIM

Load matching efficiencies up to 99% by optimizing

number of junctions



TPV Cell Fabrication Sustained at GA

General Atomics Clean Room

All process steps are performed in house

Epi wafers are supplied by Sandia National Lab

In-house material characterization used to

determine material quality

TPV Cells

Before Dicing

General Atomics has the facilities and capabilities to

deliver TPV cells and systems



2 arrays fabricated by General Atomics

Contain 4 strings of 4 MIMs in BeO

30 junction 0.6 eV InGaAs

VOC = 12V

ISC = 0.24 A

FF = 70-72

String VMP = 37.9 V

String PMP MIN = 8.0 W

Performance exceeded 26% larger legacy array

From Dave Wolford, Overview and Status of Radioisotope Thermophotovoltaic (RTPV) Power System Development

for Space Exploration Missions TPV-9 World Conference, 2010

NASA GRC RTPV Test Panel Built by GA

GA built the best panel tested by NASA and maintains that capability



The pellet container design conforms as

closely to the NASA GPHS design as is

possible, working from publicly

available information.

GPHS Design Based on Current NASA Heat Sources

Carbon Fiber Sleeve

Iridium

Cladding

Graphite Impact Shell

Aeroshell

Pu-238 Pellet

GPHS GA

Iridium Cladding 0.55 mm(minimum)

0.55 mm

Graphite Impact Shell

~5 mm 5 mm

Carbon Fiber Sleeve

~2 mm 2.4 mm

Aeroshell ~5 mm 6 mm

Total shielding

thickness

12.7 mm 14.4

mm

CSNR’s cermet fuel would be an enabling technology for much

higher-performing TPV systems as it requires little-to-no additional packaging (pressure containers, etc)

Slide 12 of 19



TPV Power Source for Space Power

~2x the efficiency of traditional thermoelectric RTGs

- Reduced fuel loading = lower weight and fuel cost

Scalable from 1 mW to >50 W

- Higher efficiency than competing technologies

20+ year life

- Proven minimal neutron TPV cell degradation

Solid State – no moving parts

GA 2 We TPV

battery next to

a standard D-cell

Ideal for outer

planetary exploration

or deep space

missions.

Launch 1 Year EOL 2 Year EOL 10 Year EOL

20 Year EOL

P0 61.502W

T BOL 986.653K

hsysB 10.946 %

PB 6.732 W

mf 141.216 gm

H_bat 7.372 cm

D_bat 6.13 cm

V_bat 217.566 cm3

mission_duration 1 yr

Pti 61.078W

T EOL 985.362K

hsysE 10.528 %

PE 6.43 W


Pti 60.656W

T EOL 984.071K

hsysE 10.153 %

PE 6.159 W


Pti 56.987W

T EOL 972.455K

hsysE 7.86 %

PE 4.479 W


Pti 52.621W

T EOL 957.612K

hsysE 6.161 %

PE 3.242 W



Electric Power Out

Thermal Power

EfficiencyFuel Mass

Thermal Density

mWe per gm fuel

Flight-Launched NASA/Aerodyne MMRTG

120 W 2000 W 6% 4800 gm 1.09 W/cm^2 25 mW/gm

NASA GPHS brick TPV withGA built panels

38 W 250 W 15% 570 gm 0.64 W/cm^2 66 mW/gm

GA new GPHS Design 6.7 W 62 W 11% 140 gm 0.54 W/cm^2 50 mW/gm

GA TAPS 3.0 W 30 W 10% 69 gm 0.58 W/cm^2 43 mW/gm

TAPS pellet cavity filled 21.68 W 51 gm 0.50 W/cm^2

TAPS form factor with 1.5mm Iridium clad

cermet43.98 W 100 gm 1.01 w/cm^2

LANL pellet cavity filled 30.7 W 70 gm 0.57 W/cm^2

LANL form factor with 1.5mm Iridium clad

cermet58.81W 140 gm 1.09 W/cm^2

GPHS pellet with cladding

44.363 W 100 gm 1.25 W/cm^2

NASA Power Source Comparison

Thermal power per unit surface area is a major driver of performance in TPV systems

-Increased emitter temperature

-Higher cell performance and efficiency

-Increased thermal power

-Reduced pellet surface area

Strauch et al., Radioisotope Fueled TPV Power Systems for Space Applications



TPV Power Conversion – Optical Considerations

Emitter Filter and TPV CellHeat Source

radiativelyor

conductively coupled

Considerations: Radioisotope Power density Radiation leakage

Considerations: Selective photon

emission Mechanical properties Long term operation Evaporation rate Surface Quality

Considerations: Long-term operation Radiation degradation Minimized absorption Transmission of convertible light Reflectance of non-convertible light Surface Quality

Convertible photons

Non-convertible photons

TPV System Components

Photonic cavity and thermal control is critical for high system efficiency



Power increases as temperature to the 7th

power

With selective emitter (SE) a given source operates at a higher temperature

2 We battery operates currently at ~1050K

System Efficiencies

Without SE With SE

950K 4.7% 5.6 %

1050K 7.2% 8.5%

1100K 8.4% 10.1%

1200K 10.3% 10.9%

Selective Emitter and Temperature Dependence

InGaAs Cell

Quantum Efficiency

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6

wavelength in micron

Emitter Temperatures: 1100 K

1050 K

950 K

Heat radiation with

Selective Emitter

Heat radiation without

Selective Emitter

The selective emitter is instrumental for high system efficiency



Front Side Filter Increases Efficiency by

Reducing Cell Temperature

Wavelength (m)

Re

fle

ctivity,4

5

AO

I

0 5 10 150

10

20

30

40

50

60

70

80

90

100

Interference Stack

Tandem Filter

Plasma Layer

Me

asu

red

Re

fle

ctivity, 45 o

AO

I (%

)

BAD (2-6 µm)

Interference Filter

InP Substrate

InPAs Plasma Layer

Glue

TPV Cell

Heat Source

Photon Emission

Anti-Reflection Coating

BAD (6- ∞ µm)

Anti-Reflection Coating

GOOD

(1-2 µm)

TPV Cell and filter stack and Layers

Non convertible photons in the TPV device become phonons in the cell

Phonons increase cell temperature & reduced voltage, power & efficiency

Spectral measurements of filter and stack

Tandem Filter Combines Performance of Interference Filter & Plasma Filter

Resulting in Increased Source Temperature & Higher System Efficiency

Front side filters fabricated by Rugate Technologies



Control box

TPV Power Source Testing

High Power Battery with Passive Cooling Fins

Hermetically sealed high power battery package

Demonstration of TAPS battery in a laboratory environment shows true performance and efficiency

GA has performed fueled tests for MIPS and electrically heated tests

at both the MIPS scale (5-50 mW) and 2 W Power Source scale



2 W TPV Power Source Performance - Output Power

Extensive system testing has

been performed and data gathered

System testing with legacy 10+ year old

TPV cells and filters

Measured pellet power conditions

correspond to fuel density and loading

for terrestrial application with pressure

containment

Cell development 90% of legacy best

System and design highly optimized and

ready for qualification testing-0.2

-0.15

-0.1

-0.05

0

0.05

0 5 10 15 20 25 30 35 40

Cu

rre

nt (

A)

Voltage (V)

Clamshell 1

Clamshell 2

Battery, clamshells connected in series

6 times better hex chip

Prediction based on prior data

Pmax = 2.7 W (h = 9.0%)Pmax = 2.3 W

(h = 7.6%)

30 W Pellet, Thot = 1069K

Pmax = 3.0 W (h = 10.1%)

Power Source performance demonstrated with a clear path to >10% efficiency

Pellet

Power,

Watts

Pellet

Temp,

K

Measured

Power

Output, W

Measured

Efficiency,

%

Efficiency with

Best Cells and

Filters, %

20 977K 1.5 4.9% 6.8%

25 1026K 2.3 6.3% 8.5%

30 1069K 3.0 7.6% 10.1%

34 1106K 3.6 NA 11.1%



TPV Power Source Scalability Modeled and

Demonstrated at Different Scales

Fuel

Density,

gram/cc

Pu238

Mass,

gram

Pellet

Power,

Watts

Power

Source

Output, W

5.9 35.7 20 1.5

7.3 44.6 25 2.3

8.6 53.6 30 3.0

9.6 60.5 34 3.6

Power

Level

Pu238 Mass

needed, grams

1 mW 1.2 gm

10 mW 1.8 gm

1.5 W 35.7 gm

3.6 W 60.5 gm

7.0 W 158 gm

Verified Scalability: Model predictions match test data

0.01

0.1

1

10

100

1000

10000

0 10 20 30 40 50 60 70 80 90 100 110

Elec

tric

Po

wer

Ou

tpu

t (m

We)

Battery Volume (cc)

DARPA MIPS program

Operating for over 414 days

Data using

electric heater

Predictions of

performance using LANL fuel pellet for various

fuel densities

Modelled data

1 to 2 We window

Model accurately predicts electrically

heated and isotope fueled systems

TPV Power Source

Power Levels and

Fuel Loadings

The 7 W version

includes full

impact shell and

aeroshell based

on GPHS design

Power source

performance

depends on fuel

density, purity

and mass. NASA

system will have

more fuel.

• 1-100 mW – AA cell size• 100 mW-2 W – D cell size• 2W – 20 W – Soda can size

Hardware developed, modeled and tested



TPV Power System Long Term Neutron Testing

0

10

20

30

40

50

60

70

80

0 10 20 30 40 50

Spec

ific

Po

wer

(We/

g-23

8Pu

)

Estimated Time with PuO2 (years)

TAPS - 2W

NASA - Voyager

NASA - MMRTG Mars RoverGA - 2 W RTPV

NASA -Voyager

MIPS program - fueled testing

140 days of Cu244 testing equivalent to

160 yrs with Pu238

414 days of continuous testing with Pu238

Cell degradation less than 1%/year

RIMS program had NRL perform Monte

Carlo analysis and e-beam neutron cell

testing showing <1%/year damage

0

0.05

0.1

0.15

0.2

0.25

0.3

0 50 100 150 200 250 300 350 400 450

Ma

xim

um

Po

we

r (m

W)

Time (days)

Curium Pellet

Plutonium Pellet

Predicted Output Power

244Cm 238Pu

Neutrons per spontaneous fission 2.72 2.22

Spontaneous fission branching ratio 1.37x10-4 % 1.85x10-7 %

Activity per gram of isotope 2.99x1012 dis/s-g 5.94x1011 dis/s-g

Neutrons emitted per sec per gram 1.12x107 n/s-g 3.81x103 n/s-g (1)

Fuel loading 0.2 g 1.4 g

Neutrons per sec 2.23x106 n/s 5.55x103 n/s

Acceleration factor at beginning of life 1 420

Curium fuel used to measure

neutron degradation of TPV cells

GA RTPV

Proven minimal TPV device degradation



FuelElectric

Power Out [W]

Efficiency [%]

Fuel Mass [gm]

Gamma Radiation [mrem/hr]

Neutron Radiation [mrem/hr]

Battery Volume [cm^3]

Battery Mass [gm]

Pu-238 Battery to Test Pu-238 1.55 7.8 50.6 0.382 0.825 69 665

Americium Same Output

Am-241 1.55 6.0 316 11.5 1.39 130 1380

Americium Same Battery Mass

Am-241 0.164 2.2 91.4 3.43 0.415 62 653

Americium Same Battery Volume

Am-241 0.248 2.8 110 4.10 0.496 69 723

238Pu and 241Am NASA Power Source Comparison

Two isotope designs for NASA applications developed

Modeled performance for ~1.5 W battery based on current tested design



What: Deliver long lived power sources for NASA Applications

Why: Best current solution for less than 100 W applications

requiring high efficiency long life power

Impact: New missions/operations possible, conserves limited fuel reserves while enabling NASA’s Space Science continuing missions

Parallel Testing and Development for fast track to flight missions

- LANL Pellet test: low cost and provides data while cermet fuel is developed and tested, ~$1.5M

- INL Am241 cermet development and arcjet testing

- Full qualification of balance of system components, ~$12-15M

More Missions are enabled by low fuel need and available scaling

- ISS flight test w Am241 cermet source – low power demo

- Cubesat, small landers, sensors, Europa mission

Path Forward – Enabling Continued NASA Missions

Through Efficient Use of Pu Fuel and Small Scales



Partners and Resources to Succeed for NASA’s Mission

Idaho National Laboratory (INL)

Battery assembly and CSNR

Oak Ridge National Laboratory (ORNL)

Fuel development and cladding

Los Alamos National Laboratory (LANL)

Pellet isotope preparation and assembly

(sealed source)

Sandia National Laboratory (SNL)

Wafer growth and testing

• Contact Information

• Jason Strauch: [email protected], (858)-999-5239

Partners to Form NASA Team

mailto:[email protected]


Radioisotope TPV Power Systems for SpaceGeneral Atomics Proprietary Information

Back Up Slides



Special Form Testing Status

Note: ANSI class 4 impact test and 49CFR173.469 percussion test are very similar; the more stringent ANSI

class 4 test will be performed. The Pacemaker Interim Guidance is 25% more energy impact than ANSI

Class 4 (equivalent of 2.6 kg mass from 1 m). Green has been completed, blue are ongoing efforts.

All tests are followed by leak tests meeting the ISO 9978 standard.

• Double E-beam welded,

90Ta/10W

• Er2O3 fuel surrogate

• Cumulative testing

Test ANSI Class 4 ANSI Class 5 49CFR173.469 Pacemaker Interim

Guidance

Temperature -40oC (20 min)

+400oC (1h) and thermal

shock 400oC to 20

oC

-40oC (20 min)

+600oC (1h) and thermal

shock 600oC to 20

oC

800oC (10 min) 800

oC (30 min)

External Pressure 25 kPa abs. (3.6 psi) to 7

MPa (1,105 psi)

25 kPa abs. (3.6 psi) to

70 MPa (10,153 psi)

1000 kg crush test

Impact

2 kg (4.4 lb) from 1 m

(3.28 ft.)

5 kg (11.0 lb) from 1 m

(3.28 ft.) Drop from 9 m (30 ft.)

onto target specified in

49CFR173.465

50 m/sec

Percussion Test Place on a sheet of lead,

struck by a steel billet 1.4

kg (3 lb) from 1 m (3.3

ft.), see Note 1

Vibration 3 times 30 min 25 to 80

Hz at 1.5 mm amplitude

peak to peak and 80 to

2000 Hz at 196 m/sec2

(20 g)

Not used

Puncture 50 g (1.76 oz) from 1 m

(3.28 ft.)

300 g (10.6 oz) from 1 m

(3.28 ft.)

Leaching

/Corrosion

7 days in water at RT, pH

6-8, 10 micromho/cm at

20oC. Dist. water at 50

oC

for 4 h

Seawater linear

corrosion less than 1

m/year

Temperature then

crush

800oC (30 min) then

1000 kg

Temperature at

pressure

500oC (30 min) at

pressure (33 yr.

equivalent at 627oC)

Temperature at

pressure -

cremation

1300oC (30 min) at

pressure (10 yr.

equivalent)

826K at 13,800 psi



b-

T1/2 = 2.6a

T1/2 = 138.4d

n

T1/2 = 87.7a

n

T1/2 = 18.1a

b-

T1/2 = 128.6d

Phase II & Phase IIIA testing and battery life testing

Not available, need to develop production pathway

Non-domestic source with high toxicity and low melting temperature

Non-domestic source, high radiation due to impurities

Phase IIIB source with oxygen exchange

b-

T1/2 = 2.6a

T1/2 = 138.4d

n

T1/2 = 87.7a

n

T1/2 = 18.1a

b-

T1/2 = 128.6d

Phase II & Phase IIIA testing and battery life testing

Not available, need to develop production pathway

Non-domestic source with high toxicity and low melting temperature

Non-domestic source, high radiation due to impurities

Phase IIIB source with oxygen exchange

(1) Includes neutrons due to <a,n> reactions with oxygen assuming 90% 16O enrichment (1,400 n/s-g)

244Cm 238Pu








Using 244Cm for Neutron Degradation Acceleration Testing



0

50

100

150

200

250

300

350

400

450

0 20 40 60 80 100 120

Pre

dic

ted

Tim

e U

sin

g 2

38P

u (

years

)

Measurement Time Using 244Cm (days)

Using 244Cm for Neutron Degradation Acceleration Testing

244Cm 238Pu








130 days of testing with 244Cm have been completed

26 yrs

57 yrs

100 yrs



GA Cleanroom Facility

In 2012, GA opened a state-of-the-art 1000 sq. ft. class 100/1000

cleanroom facility for semi-conductor materials engineering, photonics,

and electronic material fabrication.

Nanoscale Fabrication: Optical lithography,

Advanced dry etching

Thin-film deposition

Wet chemical processing

Thermal processing

Metrology

Back-End Processing



Cleanroom Full Equipment Capability

Oerlikon Leybold Univex

450B E-Beam Evaporator

Oxford Instruments PlasmaPro800+ Plasma Enhanced

Chemical Vapor Deposition (PECVD)

Reynolds Tech

Wet Process Hood

Karl Suss MA6 Mask Aligner and

Laurell Spin Coater

Oxford Instruments NGP 80 Reactive Ion Etch (RIE)Keyence VHX-1000E Digital Microscope

and Bruker Dektak xA



Characterization and Testing

Device Characterization and back end

processing equipment, including: FTIR, probe

stations, UV-VIS spectrometer, vacuum

chambers for a variety of tests, as well as in

house SEM and (in fall 2013) ellipsometry.

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