“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 The GaN device is fabricated using standard CMOS production tools 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