“G N IR A I t d ti ” “GaNpowIR–An Introduction”

“G N
“GaNpowIR
IR – An
A IIntroduction”
t d ti ”
February 2010
1
Outline
• Why is GaN interesting for power devices?
• What is GaN? What do we refer to as “GaN based power devices”?
• What are the barriers to commercialization of GaN based power devices?
• How does IR’s GaNpowIR technology platform overcome these barriers?
• What is the current performance of GaNpowIR based power devices?
• First GaNpowIR Production Product Release : iP2010
• Application Demonstrations
2
Silicon based power devices reaching maturity
Enabling Rapid
Commercialization of
Switch Mode
Power Supply
In 3-5 years, expect
1 2 % of applications to
1-2
adopt GaN technology
Enabling higher
levels of integration
for dense and efficient
power conversion
3
Figure of Merit: Tradeoffs
FOM = Ron*Qsw* Cost
Ron*Qsw
Ron*Area*Cost
FOM =
efficiency x density
cost
Qsw/Area.
Trr
4
Dramatic Improvements in Power Device FOM
C
Comparison of R
i
f Ron for Si, SiC, and GaN f Si SiC
dG N
4H-SiC
Measured data
EEcrit : Si = 20 V/μm , GaN = 300 V/
it Si 20 V/
G N 300 V/ μm
Ref: N. Ikeda et.al. ISPSD 2008 p.289
5
HEMT-FET Structure
2D Electron Gas
ϕb
1.5
0.5
0.0
0.1
0.2
0.3
X (Al fraction)
a J. Van Hove, SVTA & J. Redwing, ATMI
2
13
1
a
Measured
Calculated
1.0
0.0
2.5
20
2.0
2DEG Density (10 /cm )
2.0
13
2
2DEG Density (10 //cm )
Schottky/AlxGa(1-x)N/GaN
0.4
x=.35
x=.25
x=.15
ΦGaN=1.0 eV
1.5
1.0
0.5
0.0
100
200
300
400
AlGaN Thickness (A)
6
Commercializing GaN Technology
What are the requirements
q
for commercially
y viable GaN based p
power devices?
• Performance / Cost Competitive : Epi + substrate < $3/ cm2
• I leak
l k < 1 µA
A / mm , IIon / Ioff
I ff > 107
• 2 DEG mobility > 1800 cm2/Vs
• Crack Free epi with low active defect density
• Yields >80% for 10mm2
• Ron, RQ, Isat, Vp, Ileak are stable in operation
• Large
g diameter epi
p with < 50 µ
µm bow
• High Volume ( > 10 k wafers/ wk) Si Wafer Fab Compatible
Supply
l needed:
d d >10
106 150
1 0 mm wafer
f equivalents
i l
((to achieve
hi
10% penetration
i off
•S
total market at current utilization).
7
Mana
age Strain
GaN Epitaxy Substrate Selection
Manage Defects
From R. Korbutowicz, et al. Crystal Res. Technol 40, No 4/5, 503-508 (2005)
8
Substrates for GaN epitaxial growth
Sapphire
• Thermal expansion coefficient close to GaN: supports thick films
without thermal cracking.
• Commercial Diode Products have been demonstrated
• Large volume used for GaN based LEDs
• Poor thermal conductivity limits usefulness as a substrate for power
electronics.
• Limited in size and quality at larger diameters (6 to 8”).
• Expensive since they are wafered off the growth axis ( >~ $ 5/cm2 ).
9
Substrates for GaN epitaxial growth
SiC
• Silicon
Sili
C
Carbide
bid substrates
b t t available
il bl up to
t 4 inch
i h diameter
di
t
( future 6 “ economic supply in doubt).
• Nucleation and growth are relatively simple.
• Thermal conductivity is high so higher power densities are
attainable.
• Commercial FET products have been demonstrated
• SiC defects propagate into the GaN film and affect yield.
• Too Expensive for general use in high volume power electronics
(>
>~ $ 20 / cm2).
)
10
Substrates for GaN epitaxial growth
Silicon
• Large thermal and lattice mismatch make multiple layers for
strain management essential
• “Perfect” crystal, Perfect surface finish no substrate defect
p p g
propagation.
• Large diameters (6 to 12”) readily available in large quantities at
low cost
( < $ 0.50 cm2)
• Compatible with established high volume manufacturing facilities
and equipment
• Commercial FET products have been demonstrated (eg. Nitronex)
11
GaNpowIR – An Introduction
• A Commercially Viable GaN-based power device platform
• Based on Proprietary GaN-on-Si Hetero-epitaxy
• Utilizes low cost high quality 150 mm Si wafer substrates
• Device
D i manufacturing
f t i
process is
i CMOS compatible
tibl
• Standard high volume manufacturing disciplines applied
• Industry standard quality systems utilized
• Extensive intrinsic reliability studies performed
• Standard product reliability tests applied to device qualification
• First production product released February 2010
12
IR GaN Heteroepitaxy
13
Depletion Mode GaN HEMT Structure
ƒ The GaN device is fabricated using standard CMOS production tools
ƒ The device is Metal Insulator Semiconductor, hence low gate leakage
Gate Dielectric
S
G
D
AlGaN
2 DEG
GaN
Transition Layers
Silicon S
Substrate
bstrate
14
IR On state characteristics (Wg= 200µm, Lg= 0.3µm)
1E+3
500
1E+1
400
Id(mA/mm))
Id(mA/mm))
1E‐1
300
200
1E‐3
Vds=0.1V
1E‐5
Vds=5V
100
1E‐7
0
1E‐9
0
2
4
6
8
Vds(V)
10
‐7
‐6
‐5
‐4
‐3
‐2
‐1
0
Vgs(V)
Id vs Vds for Vg=0,-1,-2,-4V
15
IR Transfer Curve for large device (Wg=850mm, Lg=0.3µm)
Ion/Ioff > 1012
Gmax > 300 S
Ig < 100 nA
16
Low Voltage FBSOA (Width=960mm)
400
Vg=‐3V
350
Idd(A)
Vg=‐2V
300
Vg= 1V
Vg=‐1V
250
Vg=0V
Vg=1V
200
Maximum specified
operating condition of
device in ip2010
150
100
50
0
0
10
20
30
40
50
Vds(V)
• SOA of the device is wider than the operating condition
17
Low Voltage FBSOA (Width=960mm)
400
Vg=1V (@25C)
350
Id
d(A)
300
Vg=1V Vg=1V
(@125C)
250
200
Maximum specified
operating condition
of device in ip2010
150
100
50
0
0
10
Vds(V)
20
30
• Device exhibits robust FBSOA at 1250C
18
HV Reverse Blocking Characteristics
( Wg=100 mm, Lg=2um)
Ion/Ioff > 108
1.2E-06
B r e a k d o w n V o l ta g e (V )
1000
Idrain (A/mm)
1.0E-06
8.0E-07
6.0E-07
800
600
400
200
0
5
7
4.0E-07
9
11
13
15
17
19
Lgd(um)
2.0E-07
0.0E+00
0
100
200
Vg=-10V , I BV = 0.1 uA / mm
300
400
500
600
700
800
900
1000
Vdrain (V)
19
Output Characteristics of 600V device
Wg= 100 mm, Lg=2um
Ion/Ioff(600V) > 108
Vg=0V to -3.5V, step size=0.5V
20
ID (A)
15
10
5
0
0
5
10
15
20
25
VDS (V)
20
Rc Distributions
21
Device Characteristics (Continued)
2X increase in Rdson from -400C to 1250C
22
Rds(on) Stability During HTRB
HTRB Vds= 14.5V, Vgs= -7V, T= 150C
Lot 1, RDSON @ 5A
2.500
2.400
2.200
2.100
2.000
1.900
1.800
1.700
1.600
436
68
420
00
369
96
352
28
336
60
319
92
302
24
285
56
268
88
252
20
235
52
84
218
2016
184
48
80
168
1512
134
44
117
76
100
08
84
40
67
72
50
04
33
36
16
68
1.500
0
RDSON
N in mOhm
ms
2.300
Test Hours
23
Igss Stability During HTRB
HTRB Vds= 14.5V, Vgs= -7V, T= 150C
Lot 1 IGSS @ -7.5V VGSS
4368
4200
3864
3696
3528
3360
3024
2856
2688
2520
2352
2184
1848
1680
1512
1344
1176
1008
840
672
504
336
168
0
IGSS i n Amps
100.0E-9
90.0E-9
80.0E-9
70.0E-9
60.0E-9
50 0E 9
50.0E-9
40.0E-9
30.0E-9
20.0E-9
10 0E 9
10.0E-9
Test Hours
24
43
368
42
200
38
864
36
696
35
528
33
360
31
192
30
024
28
856
26
688
25
520
23
352
21
184
20
016
18
848
16
680
15
512
13
344
11
176
10
008
840
8
672
6
504
5
336
3
168
1
0
VP in Volts
Vp Stability at HTGB, Vgs = -8.5V, T = 150°C
HTGB Vgs= -8.5V, 150C
Lot 1 VP @ 15 mA
4.500
4.000
3.500
3.000
2.500
2.000
Test Hours
25
Temperature Cycling, -40°C – 125°C
Temp Cycling -40C-125C
Lot L8 RDSON @ 5A
RDS
SON in mO
Ohms
2.500
2.000
1.500
1.000
0.500
0.000
0
250
500
1000
Number of
Cycles
Test
Hours
26
iP2010 – 1st GaN product: Feb ’10 release
‰ Power stage product
‰ 6.5mm x 7.65mm x 1.66mm
‰ 30A rating
ti
‰ 250kHz – 2MHz operation
TP5
27
iP2010, Gen 1.1 – Measured Performance
28
High Current LV POL (VRM) – Projected
C A
Can
Achieve
hi
> 94% efficiency
ffi i
from
f
10A tto 100A – 4 phase
h
95%
GaN Gen 2 Solution
93%
GaN Gen 1.1 Solution
Efficiencyy
91%
Best Si Solution
89%
Std Si Solution
87%
85%
83%
5
10
15
20
25
30
Load Current (A)
( )
700 kHz Vin =12 V, Vout = 1.2 V
Circuit Simulations
29
GaN Benefit in LV POL DC-DC Conversion
Increasing Frequency : Significant Footprint Reduction
300 kHz
1 MHz
3x PCB
reduction
30
Measured High Frequency Buck Converter Efficiency
12 Vin to 1.8 Vout POL ( includes driver, switch, Inductor, PCB losses)
95%
93%
91%
E
Efficiency
89%
87%
85%
5MHz 70nH 2.2mOhm
4MHz 70nH 2.2mOhm
3MHz 70nH 2.2mOhm
2MHz 150nH 0.25mOhm
1MHz 150nH 0.25mOhm
83%
81%
79%
77%
75%
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20
Iout (A)
3/1/2010
31
5MHz DC-DC Module Waveforms
LGD
Vsw
5MHz Vsw and LGD Waveforms
32
10MHz POL Switching 12 V to 1.8 V, 12 A Iout
Vsw
LGD
• GaNPowIR Gen 1.0
1 0 (prototype) > 81% Efficiency at 10 MHz
33
RXQ
Qg Figure
e of Meriit (mOhm
m-nC)
Possible GaN LV FOM Projection vs. Time
50
45
Next Si
40
GaN
Gen 1.1
35
30
25
GaN
Gen 2.0
20
15
GaN
Gen 2.1
10
5
0
2008
2009
2009
2010
2011
2012
2013
2014
34
Possible 150V GaN FOM Projection vs. Si
Rds on in 5 x 6 mm Package (150V Normally off
Rds-on
with free wheeling diode)
16
B t Si
Best
14
Seven Fold
Reduction In Rdson in 5 x 6 mm
Package vs Si
12
Milliohm
10
MV GaN
Gen 1.1
8
MV G
GaN
NG
Gen
1.2
6
MV GaN
Gen 1.3
MV GaN Gen
2
4
2
0
2009
2010
2011
2012
2014
35
Cascoded GaN switch: Easy to use
100
120
10
25°C
GaN Switch
3.5V
100
80
0
80
3.25Vgs
10
-10
Irr (A)
ID (A)
ID (A)
60
60
-20
40
40
3Vgs
GaN FET Body Diode
-30
Si Switch
20
20
CoolMOS Body Diode
2.75V
0
1
2
3
4
5
-40
2.5V
0
0
5
VGS (V)
10
-150
15
20
-100
-50
0
50
100
Time (ns)
150
200
250
300
VDS (V)
D
Highlights:
• Normally Off operation
• Up to 10x better Figure-of-Merit than silicon equivalent
4
Compared to Si solutions:
G
• Much Lower reverse recovery losses
g in smaller package
p
g
• Lowest Rdson and Qg
• Lower EMI
S
36
600V Device Switching Waveforms Comparison
6
SiC 600V Diode
Si 600V UltraFast
600V GaN diode
4
Irr (A)
2
0
-2
-4
-6
-100
-50
0
50
100
150
Time (ns)
GaN Rectifier vs Diode
GaN HEMT vs.
vs IGBT
All Switches
Rg=50ohm
VDD=300V
VDD
300V
ID=6A
50V/div
100ns/div
37
Summary and Conclusions
• GaN based Power devices have been demonstrated with much
improved performance FOM’s
• GaNpowIR platform results in high performance, proven stable
operation of devices and circuits
• First commercialized GaN/Si switching power transistor based
product , iP2010 is now released
• Benefits
B
fit have
h
been
b
demonstrated
d
t t d with
ith in
i circuit
i
it performance
f
• IR’s GaNpowIR platform has overcome the greatest cost
b i
barriers
off GaN
G N based
b
d power devices
d i
and
d is
i poised
i d to
t address
dd
a
wide range of power conversion applications from 20-1200V
• More
M
coming:
i
150V CY2010
CY2010, 600V CY2011
38