Development of reliable, efficient, medium voltage (2.5kV-15kV) SiC power MOSFETs for new applications

Development of reliable, efficient, medium voltage (2.5kV-15kV) SiC power MOSFETs for new applications Cree Power Sept 2014 PSMA Webinar Jeff Casady, +001.919.308.2280 or jeffrey_casady@cree.com Copyright 2014, Cree Inc. 1

Outline SiC MOSFETs at Cree a brief introduction Existing portfolio Reliability Existing portfolio applications Future SiC MOSFET products scaling to medium voltage SiC MOSFET ratings compared to Si IGBT ratings Engineering sample status medium voltage SiC MOSFETs Example application using medium voltage SiC MOSFETs 2

Cree SiC Diode Portfolio Beginning in 2002 >70 products and growing Package Styles: TO-220 TO-247 Full-PAK DPAK (TO-252) D2PAK (TO-263) QFN (surface mount) Isolated TO-220 Bare Die for Modules: 2A 50 A; 650-1700V 50 Amp Chip Set Released 2013 CPW5-0650-Z0 50B: 650V, 50A Schottky Diode CPW5-1200-Z050B: 1200V, 50A Schottky Diode CPW5-1700-Z050B: 1700V, 50A Schottky Diode Copyright 2014 Cree, Inc. pg. 3

Cree SiC MOSFET Portfolio Beginning in 2011 4 1200V MOSFETs (Bare Die) CPM2-1200-0025 (25mΩ; 60A) CPM2-1200-0040 (40mΩ; 40A) CPM2-1200-0080 (80mΩ; 20A) CPM2-1200-0160 (160mΩ; 10A) >13 products and growing 1200V MOSFETs (TO-247) C2M0025120D (25mΩ; 60A) C2M0040120D (40mΩ; 40A) C2M0080120D (80mΩ; 20A) C2M0160120D (160mΩ;10A) C2M0280120D (280mΩ; 7A) 1700V MOSFETs C2M1000170D (1Ω, 3.0A) TO-247 CPM2-1700-0040 (40mΩ; 50A) Bare Die now sampling pg. 4

Cree All-SiC Power Module Portfolio Beginning in 2012 5 50 mm Platform Half-Bridge Configuration CAS100H12AM1 (1200V, 100A) XAS125H12AM2 (1200V, 125A) XAS125H17AM2 (1700V, 125A) > 7 products and growing 45 mm Platform 6-Pack Configuration CCS050M12CM2 (1200V, 50A 6-pk) CCS020M12CM2 (1200V, 20A 6-pk) 62 mm Platform Half-Bridge Configuration CAS300M12BM2 (1200V, 300A) CAS300M17BM2 (1700V, 250A) pg. 5

Cree 1700V, 8mΩ, ½ bridge power module released Full commercial release September 2014 6 Gate drivers, app notes available First all-sic power module released commercially @ 1700V Available globally Digikey, Mouser, Richardson/Arrow (right), 2 channel; 1.2/1.7 kv 62 mm module gate driver direct mount pg. 6

Section SiC MOSFET Reliability Data Copyright 2012, Cree Inc. 7

Proven Reliability with Industry-Leading Standards pg. 8 Cree Field Failure Rate Data since Jan. 2004 through Mar. 2014 0.12 FIT rate is 10 times lower than the typical silicon SiC diodes first released in 2001 SiC MOSFETs first released in 2011

Reliability Meets All Commercial and Military Requirements Accelerated HTRB Testing at 150 C Accelerated TDDB Testing at 150 C Time (Hours) Tested to failure at very high Drain voltages Time (Hours) Tested to failure at very high G- S voltages MOSFETs have extrapolated MTTF of 30 million hours Gate oxides have extrapolated MTTF of 8 million hours at +20V continuous 9

C2M V TH Stability at High Temperature, +/- DC Bias pg. 10 Positive Bias Accelerated at 175 C Negative Bias Accelerated at -15V V TH (V) 4.0 3.5 3.0 2.5 2.0 1.5 In-Situ Monitored Data V TH (V) 4.0 3.5 3.0 2.5 2.0 1.5 In-Situ Monitored Data V GS = -15V T = 150 C 1.0 0.5 0.0 V GS = +20V T = 175 C 0 200 400 600 800 1000 Time (hr) 1.0 0.5 0.0 0 200 400 600 800 1000 Time (hr) Extremely stable for 1,000 hours under positive and negative bias Accelerated beyond data sheet to see any measurable change Average shift under positive bias: DV TH = 0.06 V, DR DS-ON = 0.1 mω Average shift under negative bias: DV TH = 0.01 V, DR DS-ON = 3.2 mω

Cost reduction from volume and device refinement 100% 600V Schottky 1200V Schottky MOSFET % of Intro oduction Cost 80% 60% 40% 20% Gen 1 Schottky Gen 2 Schottky Solid Lines = Actual Dotted Lines = Projections Gen 3 Schottky Gen 4 Schottky Gen 1 MOSFET Gen 2 MOSFET 0% Gen 5 Schottky 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 75 mm 100 mm Wafer Diameter Increases 150 mm

Section Partial Listing of Existing MOSFET Portfolio Applications Copyright 2012, Cree Inc. pg. 12

1200V SiC MOSFET impact to 10-50 kw boost Benefits of SiC in power electronics are compelling in 10 to 50 kw boost stage BOM cost decreases Size, weight & losses all decrease C2M0080120D compared to H3 IGBT* Size Weight BOM Losses Temperature 10 kw 50% 40% 10-20% 20% 30% 50 kw 50% 60% 10-18% 40% 40% * Reference: J. Liu (PCIM 2013) pg. 13

1200V SiC MOSFET design wins in PV inverters Through this partnership with Cree and their SiC technology, Sanix is able to capture more market share in the competitive Japan solar market, says Sanix s general manager Hiroshi Soga. Cree s... SiC switches reduced losses in our inverter electronics by more than 30% versus the silicon super-junction MOSFETs we were considering PV Inverters - lower losses, costs - better performance 1200V, 80mΩ SiC MOSFETs have been selected by Japan s Sanix Inc. 9.9kW three-phase solar inverters Higher power density, lower losses Sept 2014April press 2013 release press release pg. 14

1200V MOSFET design wins-induction heating The drop-in feature of Cree s new all-sic power module allows us to achieve 99 percent efficiency while reducing the power module count by a factor of 2.5 in our existing HF induction heating systems, said John K. Langelid, R&D manager, EFD Induction. These benefits are greatly valued as a reduced cost of ownership by our end customers. Induction Heating power supplies - 2.5X lower part count - better implied reliability - Reduction in power losses - Reduced COO May 2014 press release pg. 15

1200 V SiC MOSFETs used in on-board DC/DC converter For HEV/EV bus (Shinry) Silicon SiC DC-DC topology with 1200 V SiC MOSFET (C2M0080120D) Active clamp forward topology with 750 V DC in / 27 V DC out SiC MOSFET enabled: efficiency from 88% to 96% size and weight by 25% - 60% both cost and audible noise Eliminated cooling fans pg. 16

Compact demo 8 kw EV using 1200 V SiC MOSFET Ref: J. Liu, PCIM 2014 SiC SBD Lm Resonant Tank Cr Input 8 kw 98.1% eff 260kHz SiC MOS with heatsink Lr Board Size of 8 kw Full Bridge LLC Resonant Converter using SiC (Size: 8 x12.5 x3.5 ) > 35 W / in 3 Output Controller Gate Driver pg. 17

1200 V SiC MOSFETs used in 8 kw EV charger demo 1200 V SiC MOSFET (C2M0160120D) enables: Simpler topology, ½ the components, 260 khz, (> 35W/in 3 ) Lower system cost, > 98.1% efficient Not possible to do this in silicon Items MOSFETs 650 V Si SPW47N60CFD in 3 level 1200 V SiC C2M0160120D in 2 level CREE SiC MOSFET in Full Bridge LLC ZVS Resonant Converter J. Liu, PCIM 2014 3-level FB w/ Si MOS @ 120kHZ resonant freq. 2-level FB w/ SiC MOS @ 260kHZ resonant freq. 16 pcs 8 pcs Flying diode 4 pcs None Resonant Inductor 2 pcs 1 pc Lr=15uH (PQ3535) Magnetize transformer 2 pcs PQ5050 1 pcs PQ6560 Lm=100 uh Resonant Capacitors 35nF 25 nf MOS Drivers 8 pcs 4 pcs Peak efficiency 97.8% 98.1% pg. 18

Section Future SiC MOSFET products scaling to medium voltage Copyright 2012, Cree Inc. 19

SiC amp ratings are much less than Si 300 Amp SiC More Capable than 600 Amp Si IGBTs! 350 300 Si Amps are not SiC Amps Losses (Watts) 250 200 150 100 50 Diode Switching Conduction 0 SiC MOSFET 300 Amp, 10 khz Si IGBT 600 Amp, 3 khz System cost reduction of 20% using 1200V SiC Increased frequency reduces size and weight of magnetics Lower losses reduce system cooling requirements Amperage rating for SiC less than half required for Si IGBTs 20

SiC voltage ratings are much less than Si? 6.5 kv Si IGBT used for 3.6 kv drives (100 cosmic ray FIT rate) Si Volts are not SiC Volts 4.5 kv SiC MOSFET used for 3.6 kv line? 10 kv SiC MOSFET used for 7.2 kv? Semiconductor Power Devices: Physics, Characteristics, Reliability By Josef Lutz, Heinrich Schlangenotto, Uwe Scheuermann, Rik De Doncker Medium Voltage SiC MOSFET roadmap must respond to application 10X higher switching frequency, lower thermal dissipation possible Cosmic ray, other reliability metrics may be 100X better All requirements, eg. short circuit, surge must be understood 21

Next Generation SiC MOSFETs Smaller pitch Source Contact Metal Source Contact Metal Inter-metal Dielectric Inter-metal Dielectric N + Degenerately doped Poly Si Gate Gate Oxide N + Source P-Well N + Degenerately doped Poly Si Gate Gate Oxide N + Source P-Well Optimized doping N + 4H SiC Substrate N + 4H SiC Substrate Drain Contact Metal Drain Contact Metal Gen 2 DMOS Commercially released in 2013 R&D DMOS Same high reliability DMOS Structure, but optimized to dramatically reduce die size Reference: J. Palmour, et al (ISPSD 2014) pg. 22

Gen-1 Introduction Gen-2 Revolution R&D 12 100% 61% 42% 10 P (m W cm 2 ) R ON,SP 8 6 4 2 R cm 2 ON,SP (m W c ) 12 10 8 6 4 8.0 11.0 8.9 0 0 25 50 75 100 125 150 T J ( C) 1200 V, 80 m W, SiC DMOSFETs 2 0 Gen-1 Planar DMOS (Product, 2011) 4.8 Gen-2 Planar DMOS (Product, 2013) 2.7 4.9 Gen-3 Planar DMOS (R&D, 2014) at V G = 20 V, I D = 20 A Reference: J. Palmour, et al (ISPSD 2014) pg. 23

R&D MOSFETs Set New Standard for Low on-resistance in SiC RON,SP (mw W cm2) at VG = 20 V 15 kv 10 kv 100 6.5 kv 3.3 kv 10 Gen 1, 1.2 kv Gen 2, C2M Family 1.2 kv 1.2 kv 900 V 1 100 1,000 Breakdown Voltage (V) 10,000 Reference: V. Pala, et al (ECCE 2014) pg. 24

3.3 kv, 40 mω, 40 A MOSFET Engineering Samples pg. 25 pg. 25

3.3 kv SiC MOSFET DC Characteristics R ON,SP = 10.6 m W cm 2 at V G = 20 V 30 10 4161 V @ 10.2 A at V G = 0 V I D (A) 25 20 15 10 5 ID(0V) ID(4V) ID(8V) ID(12V) ID(16V) ID(20V) I D ( A) at V G = 0 V 8 6 4 2 5.1 mm m 9.16 mm 0 0 1 2 3 V D (V) 0 0 1000 2000 3000 4000 BV DS (V) Blocks 4.16 kv with R ds(on) of 10.6 m W cm 2! Reference: J. Palmour, et al (ISPSD 2014) pg. 26

3.3 kv/40 A SiC DMOSFET Switching Switching at 1800V, 25A 200 T J = 25 C Drain-Source Current (A) 150 100 50 T J = 100 C T J = 150 C V DS = 20 V 0 0 5 10 15 20 Gate-Source Voltage, VGS (V) 3 On Resistance, R DS ON (p. u.) 2.5 2 1.5 1 0.5 I DS = 28 A V GS = 20 V tp < 50 μs Reference: J. Palmour, et al (ISPSD 2014) 0 25 50 75 100 125 150 Junction Temperature, T J ( C) pg. 27

6.5kV, 25A SiC MOSFET I D (A) R ON,SP =50 m W cm 2 at V G =20 V, RT 80 70 60 50 40 30 20 10 ID(0V) ID(5V) ID(10V) ID(15V) ID(20V) D ( A) I D 80 70 60 50 40 30 20 10 A die =0.54 cm 2, A act =0.3 cm 2 ~ 6.8 kv @ 67 A at V G = 0 V 7.20 mm 7.20 mm 0 0 2 4 6 8 10 12 14 V D (V) 0 0 1 2 3 4 5 6 7 BV DS (kv) Blocks ~ 6.8 kv with R ds(on) of 50 m W cm 2! Reference: J. Palmour, et al (ISPSD 2014) pg. 28

10 kv, 300 mω, 20 A MOSFET Engineering Samples pg. 29 pg. 29

10kV, 20A improved SiC MOSFET R ON,SP =86 m W cm 2 at V G =20 V, RT A die =0.54 cm 2, A act =0.28 cm 2 30 25 ID(0V) ID(4V) ID(8V) ID(12V) 80 70 60 11.06 kv @ 75 A at V G = 0 V I D (A) 20 15 10 ID(16V) ID(20V) I D ( A) 50 40 30 20 5 10 0 0 2 4 6 8 10 V D (V) 0 0 2 4 6 8 10 12 BV DS (kv) Blocks ~ 11 kv with R ds(on) of 86 m W cm 2! Reference: J. Palmour, et al (ISPSD 2014) pg. 30

10 kv Improved SiC MOSFET Switching Performance Turn-Off Turn-On Deliver > 50% amps with 40% smaller Adie than Gen-1, 10kV DMOS at 250 W/cm2 Reference: J. Palmour, et al (ISPSD 2014) > 40x lower Esw than the 6.5kV Si-IGBT pg. 31

15 kv/10 A SiC DMOSFET Development 14 12 Drain Current (A) Design optimization allows BV of 15kV with the same Adie than Gen-1, 10kV DMOSFETs RON,SP=208 mw cm2 VG=20V, RT 10 15, 20 V 10 V 8 6 4 5V 0V 2 0 0 2 4 6 Drain Voltage (V) 8 20 D ra in C u rre n t (A ) 1.6E-07 1.4E-07 1.2E-07 Adie: 0.63 cm2, AAct: 0.32 cm2 1.0E-07 8.0E-08 6.0E-08 Switching Loss (mj) 15.5 kv @ < 0.2 A 1.8E-07 16 12 8 2 4000 6000 8000 10000 12000 14000 16000 Drain Voltage (V) Reference: J. Palmour, et al (ISPSD 2014) EOFF, 5A 6 2.0E-08 2000 EON, 5A 10 4 0 EON, 10A 14 4.0E-08 0.0E+00 15 kv SiC DMOSFET 18 2.0E-07 EOFF, 10A 0 4 5 6 7 8 9 10 11 12 13 14 15 Bus Voltage (kv) pg. 32

Eliminate Switching Losses with SiC MOSFETs 25x smaller switching losses compared to 6.5 kv IGBTs Device Max TJ Bus Voltage Rated Current VDSON @ Max TJ ESW,ON ESW,OFF ESW,TOT 6.5 kv Si IGBT 10 kv SiC MOSFET 125 C 3.6 kv 25 A 5.4 V 200 mj 130 mj 330 mj 150 C 7 kv 20 A 10.2 V 8.4 mj 1.3 mj 9.7 mj 15 kv SiC MOSFET 150 C 10 kv 10 A 16.3 V 10.2 mj 3 mj 13.2 mj Reference: V. Pala, et al (ECCE 2014) 33

SiC MOSFETs : >2x Voltage, 10x Frequency Compared to Silicon Power is bus voltage times current Maximum current limited by thermal chip limit 6.5kV and 4.5kV SiC MOSFETs will provide further advantage over Si IGBT Analysis assumed hard switched ½ bridge inverter topology M aximum System Power (kw ) Power Capability vs Frequency for Hard Switched Topologies 140 120 100 80 60 10x 40 20 0 1 10 Switching Frequency (khz) 100 Reference: V. Pala, et al (ECCE 2014) 34

Section Future Target Applications 35

Application Market Pull for MV SiC from: AC Medium Voltage Drives Applications Railway Applications (3.3 kv SiC already being adopted in rail) Grid-tied Solar Applications HVDC Applications (Off-shore wind, hydro, ) Grid-tied Power Distribution (Energy-intensive structures such as factories, data centers) Transport Electrification Energy Distribution Rail & Grid-tied Energy pg. 36

10 kv SiC MOSFETs in Boost Converter (Fraunhofer ISE) Advantages of medium voltage DC distribution: Flexible subunit power rating from a few kw to > 2 MW Smaller, lighter, cheaper power cables with higher voltage Eliminate large, heavy, costly transformer A Highly Efficient DC-DC-Converter for Medium-Voltage Applications Reduce number of system components Jürgen Thoma, David Chilachava, Dirk Kranzer ENERGYCON 2014 May 13-16, 2014 Dubrovnik, Croatia Copyright 2014, Cree Inc. pg. 37

10 kv SiC MOSFETs in Boost Converter (Fraunhofer ISE) Efficient, transformer-less power distribution to medium voltage grid Box is 36 cm x 30 cm Copyright 2014, Cree Inc. Fraunhofer DC-DC converter used 10kV SiC MOSFETs from Cree 30 kw DC voltage converter with 3.5 kv input voltage, 8.5 kv output voltage, 98.5% efficient 8kHz switching frequency 15X higher than possible with conventional silicon devices in the same voltage range. A Highly Efficient DC-DC-Converter for Medium-Voltage Applications Jürgen Thoma, David Chilachava, Dirk Kranzer ENERGYCON 2014 May 13-16, 2014 Dubrovnik, Croatia pg. 38