1. Lockheed-­‐Martin
Advanced
Technology
Center
J.
Michael
Pinneo,
Ph.D.,
J.D.
September
24,
2009
1
J.
Michael
Pinneo,
michael@pinneo.org

2. Survey
! I.
Diamond
synthesis
and
properties
! II.
Aerospace
applications
2
J.
Michael
Pinneo,
michael@pinneo.org

3. CVD
Diamond
-­‐
Synthesis
! Overall
chemistry:
deposition
occurs
in
diamond
metastability
region,
graphite
stability
region
! i.
CxHy
+
H0
!
Cg+
Cd
(mostly
graphite)
! ii.
Cg
+
H0
!!!
CxHy
! iii.
Cd
+
H0
-­‐>
CxHy
(~1/400
ii.)
! Yields
poly-­‐
and
single-­‐crystal
3
J.
Michael
Pinneo,
michael@pinneo.org

4. CVD
Diamond
–
Synthesis
Methods
! Hot
filament,
plasmas,
combustion,
...
4
VHF
Plasma,
8”
Combustion,
4”
linear
Microwave
Plasma,
4”
RF
Plasma
Torch
DC
Plasma
Torch
J.
Michael
Pinneo,
michael@pinneo.org

5. CVD
Diamond
-­‐
Varie7es
Scale-up Experience
Microwave Diamond CVD
30Kw, 915 MHz
Plasma Scanning
Deposition Diameter 14"
Conformal 3-D Capability
Thickness Uniformity <8% over 12"
5
Diamond
on
Si
Wafers
Diamond-­‐coated
BC
wear
blocks
and
Si3N4
ball
bearing
Diamond
heat
spreader
prototype
for
microprocessor
Diamond-­‐coated
Si3N4
fiber
Diamond-­‐coated
Si3N4
dome
(14”
dia
x
3.5”
deep)
J.
Michael
Pinneo,
michael@pinneo.org

6. CVD
Diamond
–
Thermal
Proper7es
! Thermal
conductivity
@
273°K:
8
–
25
W/cm-­‐°K
! Thermal
conductivity
peak
~
77°K:
60
W/cm-­‐°K
! Thermal
diffusivity:
1.16
cm2/sec
! Thermal
conductivity
is
high
even
in
nanocrystalline
films
! Extremely
useful
in
thermal
management
6
J.
Michael
Pinneo,
michael@pinneo.org

7. CVD
Diamond
–
Mechanical
Proper7es
! Hardness:
10,000
kg/mm2
! Modulus:
1,100
Gpa
! Poisson’s
ratio:
~
0.06
! Thermal
Expansion
Coefficient:
~
1
x
10-­‐6/°C
@
273°K
! Coefficient
of
sliding
friction
(µ):
10-­‐2
to
10-­‐3
! Sonic
velocity:
~
18
km/sec
7
J.
Michael
Pinneo,
michael@pinneo.org

8. CVD
Diamond
Op7cal
Proper7es
! Transparent:
225
nm
–>
DC
! ~
5µm
–
6µm,
intrinsic
phonon
absorption
! Refractive
Index
~
2.4
! Emissivity
@
273°K
~
0.04
8
J.
Michael
Pinneo,
michael@pinneo.org

9. CVD
Diamond
Electronic
Proper7es
! Resistivity,
intrinsic:
>
1015
Ω-­‐cm
! Resistivity,
B-­‐doped:
10-­‐3
Ω-­‐cm
! Dielectric
constant:
5.7
! Breakdown
field:
>
107
V/cm
! P
and
N
dopants:
B,
B
&
D
plasma
9
J.
Michael
Pinneo,
michael@pinneo.org

10. Aerospace
Applica7ons
Thermal
Management
10
J.
Michael
Pinneo,
michael@pinneo.org

11. Heat
Spreaders
for
Ac7ve
Devices
Device
Cold Plate
Diamond Heat Spreader!
K = 12 W/cm-°K
SiC Heat Spreader!
K = 2.5 W/cm-°K
T1
T2
Tr1
Tr2
Trn
Q
∝
(T1
–
T2)
Q
∝
1/(∑
Tr1…Trn)
11
J.
Michael
Pinneo,
michael@pinneo.org

12. Diamond
Microprocessor
Heat
Spreaders
! IR
image
of
processor
temperature
! Diamond
enabled
1.8x
clock
rate
increase
12
Die Temperature
w/ Copper Spreader
Die Temperature
w/ Diamond Spreader
Copper
Heat
Spreader
Diamond
Heat
Spreader
J.
Michael
Pinneo,
michael@pinneo.org

13. GaN
HEMT
13
5
© 2005-2006 Group4 Labs, LLC. All Rights Reserved
!""#$%&'%()*+#"%,+#-./+*+"#-)*/%0+1)2+3%&*%4#5
6(+*/-,%&'%,+#-%3&7"2+3%)3%(&*/%)*%2&89#")3&*%:)-,%-,+%3+9#"#-)&*%! #*0%:)0-,%&'%-,+%3&7"2+3;
4#5%+9)(#$+"3
<7=3-"#-+
d
T0 = 23°C
TP
!T = TP–T0
zy
!"#$%&'(%)*#'(+!$,-!,$#
J.
Michael
Pinneo,
michael@pinneo.org

14. Thermal
Management
Heat
Spreaders,
GaN
HEMTs
! Attach
100µm
diamond
heat
spreader
to
GaN
device:
! 200%
increased
power
cf.
SiC
heat
spreader;
! 1000%
increased
power
cf.
Si
heat
spreader.
Courtesy
Group
4
Labs,
and
Jonathan
Felbinger
and
Prof.
Eastman,
Cornell
University.
14
J.
Michael
Pinneo,
michael@pinneo.org

15. ! 4”
free-­‐standing
GaN
wafer
on
diamond
15
Courtesy
Group
4
Labs
J.
Michael
Pinneo,
michael@pinneo.org

16. 16
J.
Michael
Pinneo,
michael@pinneo.org
Separation
between
linear
sources
[µm]

17. GaN
HEMT
on
Diamond
! Benefits:
! Higher
output
power
! Lower
operating
temperature
! Greater
device
density
! System
Impact:
! Radar
-­‐>
increased
target
acquisition
distance
! Active
ECM
-­‐>
increased
range,
effectiveness
! Increased
MTBF
-­‐>
reduced
maintenance
$,
time
17
J.
Michael
Pinneo,
michael@pinneo.org

18. Poten7al
Applica7on
! F-­‐35
thermal
issues
! Fuel
used
as
internal
systems
heat
sink
! Low
fuel
near
end
of
mission:
! Higher
fuel
temperature
! Lower
∆T
in
thermal
transfer
chain
! Increased
avionics
temperature
18
J.
Michael
Pinneo,
michael@pinneo.org

19. F-­‐35
Thermal
Issue
! Reduce
overall
thermal
resistance
between
avionics
and
fuel
! Apply
diamond
to
thermal
transfer
path:
! Device
level:
diamond
heat
spreaders
! Card/module
level:
diamond
heat
pipes
&
plates
! Heat
exchangers:
diamond
or
diamond/SiC
composites
19
J.
Michael
Pinneo,
michael@pinneo.org

20. Op7cal
Applica7ons
! Important
properties
! Broadband
transparency
! 225
nm
-­‐>
DC
! Intrinsic
phonon
absorption
~
5
µm
–
6
µm
! Hardness
! Low
loss
tangent
(<
10-­‐4)
20
J.
Michael
Pinneo,
michael@pinneo.org

21. IR
Op7cal
Applica7ons
Rain/dust
impact
damage
on
IR
optic
(F-­‐15E)
21
J.
Michael
Pinneo,
michael@pinneo.org

22.
IR
Op7cal
Applica7ons
! Erosion
barrier
for
ZnS/ZnSe
IR
optics
! Hardness,
IR
transparency
! Can’t
CVD
direct
on
IR
material,
but
chalcogenide
“glue”
works.
! AR
coatings
are
available.
VISIBLE
22
J.
Michael
Pinneo,
michael@pinneo.org

23. Op7cs:
High
Power
Lasers
! Windows/Lenses
! High
damage
threshold
! Physically
robust
! Solid
State
Lasers
! Increased
output
! Reduced
module
volume
Northrop-­‐Grumman
100
Kw
laser,
Phase
3,
JHPSSL
Advanced
Tactical
Laser
(ATL)
23
J.
Michael
Pinneo,
michael@pinneo.org

24. Op7cs:
HPM
Windows
! DEW:
high
power
microwave
windows
(HPMW)
! High
K,
low
loss
tangent,
low
TCE
! >1
Gw
CW,
>
10
Gw
pulsed
@
90
GHz
! USAF
BAA/Raytheon
2009
win
to
provide
domestic
source
! Current
vendors:
Europe,
Asia
! >$100K
each
24
J.
Michael
Pinneo,
michael@pinneo.org

25. Mechanical,
Fric7on
&
Wear
! Important
properties
! Low
friction
! Hardness
! Modulus
! Corrosion
resistance
25
F-­‐15E
Exhaust
Flap
Mechanism
J.
Michael
Pinneo,
michael@pinneo.org

26. Machining
Opera7ons
! Diamond-­‐coated
tooling
Increased
tool
life
Higher
machining
speeds
Better
workpiece
finish
26
Diamond
–
coated
cutting
tools
courtesy
of
Crystallume,
Inc.
J.
Michael
Pinneo,
michael@pinneo.org

27. Bearings
and
Seals
! Good
coating
and
performance
increases
shown
for
diamond
on
Si3N4
ball
bearings,
BC
wear
shoes,
and
SiC
pump
seals.
! Diamond
pump
seals
in
commercial
production
by
Advanced
Diamond
Technologies,
Inc.
27
Diamond-­‐coated
pump
seals,
courtesy
of
Advanced
Diamond
Technologies,
Inc.
J.
Michael
Pinneo,
michael@pinneo.org

28. Diamond
as
a
MEMS
Material
! Hardness
&
Modulus
! Low
self-­‐adhesion/stiction
! Hydrophobic
! Tolerate
aggressive
environments
! Surface
can
be
functionalized
to
provide
sensing
capability
28
J.
Michael
Pinneo,
michael@pinneo.org
Diamond
RF
MEMS
Switch

29. Diamond
for
High
Power
Lasers
! Desirable
properties:
transparency,
K,
TCE,
damage
threshold
! Natural
diamond
laser
demonstrated
in
1985(1)
! Optically
pumped
(Ar
ion
laser)
! Lasing
medium:
H3
color
center,
530
nm
! Tunable
due
to
coupling
with
phonon
energy
levels
! Efficiency
13.5%
! Interesting,
but
natural
diamonds
too
costly
&
rare
29
(1)
Rand
&
DeShazer,
Optical
Letters,
1985
vol.
10
(10)
pp.
481-­‐483
J.
Michael
Pinneo,
michael@pinneo.org

30. Diamond
for
High
Power
Lasers
! What’s
changed?
! Large,
high
quality
single
crystal
diamonds
by
CVD
! R.
Hemley’s
group
at
Carnegie
Institute(2)
! Microwave
plasma
CVD
followed
by
HP
or
LP
anneal
! Highly
accessible
with
relatively
simple
equipment
! Cost-­‐effective
technology
30
(2)
Recent
advances
in
high-­‐growth
rate
single-­‐crystal
CVD
diamond,
Qi
Liang,
et
al.,
Diamond
and
Related
Materials,
2009
vol.
18
(5-­‐8)
pp.
698-­‐703
J.
Michael
Pinneo,
michael@pinneo.org

31. Diamond
for
High
Power
Lasers
! High
efficiency
diamond
Raman
laser(3)
! 1.2
watt
output
@
573
nm,
532
nm
pump
! Conversion
efficiency
63.5%
! Slope
efficiency
75%
! Peak
photon
conversion
efficiency
91%
! Diode-­‐pumped
diamond
Raman
laser
shown
in
2005(4)
31
(3)
Highly
efficient
diamond
Raman
laser,
Mildren
and
Sabella,
Optics
Letters,
2009
vol.
34
(18)
pp.
2811-­‐2813
(4)
Diode
pumped
diamond
Raman
microchip
laser,
Demidovich,
et
al.,
Conference
on
Lasers
and
Electro-­‐Optics
(CLEO)
Europe,
2005,
p.
251
J.
Michael
Pinneo,
michael@pinneo.org

32. Diamond
for
Hypersonic
Flight
! Challenge:
extreme
aeroheating
of
vehicle
and
control
surfaces
during
endoatmospheric
flight
(≥
2,500°C)
! Constrains
thermal
solutions
to
ablative
materials
! Ablatives
can
substantially
depart
from
nominal
aerosurface
design
during
flight
! Impact
on
vehicles:
! Increased
control
authority
required
! Increased
total
divert
energy
needed
! Increases
vehicle
weight/size,
reduces
range
! Introduces
weather
(rain,
dust)
as
launch
limitation
! Resolution:
robust,
nonablative
thermal
coating
J.
Michael
Pinneo,
michael@pinneo.org
32

33. Diamond
for
Hypersonic
Flight
! Critical
info:
diamond
does
not
bulk
graphitize
at
T
>
2,200°C
for
hours
! Suggests:
Anti-­‐oxidation
coating
+
thick
diamond
film
could
be
useful
as
a
robust,
nonablative
material
for
some
hypersonic
endoatmospheric
missions.
! Oxidation
barrier:
Re/Ir
–
affordable
because
<
10µm
! Low
diamond
TCE
–
helps
maintain
antioxidation
coating
integrity
! Diamond
hardness/modulus
–
better
resistance
to
particle
erosion
(rain,
dust)
than
ablatives
J.
Michael
Pinneo,
michael@pinneo.org
33

34. The
End
34
J.
Michael
Pinneo,
michael@pinneo.org