Introducing PowerAmerica at the 11th Annual SiC MOS workshop Dr. Victor Veliadis, CTO PowerAmerica

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1 Introducing PowerAmerica at the 11th Annual SiC MOS workshop Dr. Victor Veliadis, CTO PowerAmerica

2 Mission Summary WBG Semiconductor Material Properties Are Ideal for High Voltage/Temperature Power Applications Semiconductor Material Energy Bandgap (ev) Critical Electric Field (MV/cm) Thermal Conductivity (W/m K) Saturation Velocity (10 7 cm/s) Mobility (cm 2 /V s) Dielectric constant (ε s ) Intrinsic Carrier Conc. (cm -3 ) GaN H-SiC Si Wide Bandgap High temperature operation with reduced cooling requirements (lower n i ) Radiation hard operation Large Critical Electric Field High voltage operation at lower resistance Increased speed, smaller dimensions SiC wide band-gap results in an intrinsic temperature of over 1000 ºC Large Thermal Conductivity High power operation with lower T due to self-heating Large Saturation Velocity High Frequency operation with reduced size of passives (less weight and volume) R on-ideal = 4 V 2 BR EE CC33 µ n ε S WBG power devices offer low-resistance at high voltages and operation at elevated temperatures

SiC Low-resistance at High Voltage and Elevated

Hybrid-Electric/All-Electric Combat Vehicles Improved fuel

power generation, and limp home advantage Multi-level

transformers Mobile lightweight efficient power converters

Systems : Increased Action capability for military systems

Tallil Airbase, Iraq More electric aircraft: electric

Electric warship: Power Conditioning for Propulsion and

3 SiC Low-resistance at High Voltage and Elevated Temperature Operation Enables Military Applications Hybrid-Electric/All-Electric Combat Vehicles Improved fuel economy, enhanced stealth capability, auxiliary field power generation, and limp home advantage Multi-level Solid State Power Substation (SSPS) (Power distribution, utilities, etc.) SiC enables >50% size & weight savings over iron core transformers Mobile lightweight efficient power converters for renewable energy, reduce logistics Pulsed Power Systems : Increased Action capability for military systems Electromagnetic Railgun and Electromagnetic Active Armor Tallil Airbase, Iraq More electric aircraft: electric systems replace non-propulsive hydraulics and pneumatics Electric warship: Power Conditioning for Propulsion and Weapons (EM Railgun, High Energy Laser Shield) USS Zumwalt DDG 1000 destroyer is US Navy s first all-electric ship USS Zumwalt all electric destroyer

applications: Hybrid/electric, all/electric vehicle systems Grid-tie

discharge of energy storage systems Regenerative power (brakes,

) More electric aircraft and ship (floating microgrid) Deep well

distribution network stabilization PV DC Inverter Utility DC Bus

4 SiC Low-resistance at High Voltage and Elevated Temperature Operation for Efficient Commercial Applications Commercial applications: Hybrid/electric, all/electric vehicle systems Grid-tie renewable energy inverter systems DC-DC converters Charge and discharge of energy storage systems Regenerative power (brakes, elevators, etc.) More electric aircraft and ship (floating microgrid) Deep well drilling Battery and solid-state converter systems for power distribution network stabilization PV DC Inverter Utility DC Bus 3-Phase Inverter P.M. Bidirectional DC-DC DC Bus *A 27-MW 15-minute NiCd battery bank at Fairbanks Alaska stabilizes voltage at the end of a long transmission line

PowerAmerica is being managed by North Carolina State University.

5 PowerAmerica Mission is Summary a U.S Department of Energy WBG Semiconductor Manufacturing Institute The U.S Department of Energy launched the PowerAmerica Institute under the initiative of National Network of Manufacturing Institutes (NNMI) to commercialize Wide Band Gap (WBG) power devices. PowerAmerica is being managed by North Carolina State University. PowerAmerica is accelerating commercialization of wide bandgap semiconductor technologies by making them cost-competitive with silicon-based power electronics and reducing their perceived risk in industrial applications. Through participation in the PowerAmerica ecosystem, industry members grow their business by accelerated wide bandgap product introduction to market and University members gain by engaging in collaborative projects with industry.

Strategy Mission for Accelerated Summary Large-scale Adoption of WBG Semiconductor Devices Mission Energy Savings and Manufacturing Jobs Creation through Accelerated Largescale Adoption of WBG

6 Strategy Mission for Accelerated Summary Large-scale Adoption of WBG Semiconductor Devices Mission Energy Savings and Manufacturing Jobs Creation through Accelerated Largescale Adoption of WBG Semiconductor Devices in Power Electronics Systems Strategy Highlight Performance Advantages of WBG Devices Stress high voltage at low resistance, high temperature, and high frequency WBG device operational advantages over those of Si counterparts Establish Reliability of WBG Devices Leverage Si Reliability best practices in developing WBG reliability standards Showcase System Insertion Advantages of WBG Devices Develop packaging technology that allows for full WBG performance potential Demonstrate WBG PE system value proposition in terms of higher efficiency, and smaller weight/volume at low overall additional system cost Reduce Cost of WBG Devices (TRL 4-7) Leverage mature Si fabrication practices, and qualify WBG specific processes to enable multiple source high-yield volume production Train Workforce in WBG devices/modules/systems Benefits Job Creation, Accelerated Technology Innovation, Energy Savings, Smaller Environmental footprint

7 SiCMission Manufacturing Summary Necessitates Investment in Tools that Perform WBG Specific Processes Multiple mature Si processes have been successfully transferred to SiC. However, SiC material properties necessitate development of specific processes, whose parameters must be optimized and qualified: Etch: SiC hardness allows for only dry etching. Masking materials, etch selectivity, gas mixtures, control of sidewall slope, etch rate, sidewall roughness, etc., are being developed. Doping: conventional thermal diffusion is not practical in SiC due to high melting point. Evaluate implantation dose, species, energy, temperature, masking material, etc. Post implantation SiC recrystallization and implant activation anneal method (furnace, RTA, etc.), temperature, duration, gas flow, etc. Select anneal protective cap layer to minimize wafer surface degradation. Metallization: evaluate metals, sputter and evaporation, CTE match, resist types and lift-off profiles, metal etches etc. Ohmic contact formation: high value of metal/sic Schottky barrier results in rectifying contacts. Post deposition anneal is required for Ohmic contacts. Evaluate metals, CTE match, anneal temperature, gas flow, surface quality. Gate oxides: Poor quality SiC/SiO 2 interface reduces MOS inversion layer mobility. Develop passivation techniques to improve SiC/SiO 2 interface quality. Insulation dielectrics: thick dielectrics are deposited in SiC. Evaluate deposited dielectric defects that can affect edge termination and device reliability. Develop SiC Manufacturing PDKs

X-FAB Mission Leverages Summary Si Infrastructure and SiC Tool Investment to Offer SiC Manufacturing Services SiC JBS diodes, BJTs, and MOSFETs presently fabricated at XFAB Leverage Existing

8 X-FAB Mission Leverages Summary Si Infrastructure and SiC Tool Investment to Offer SiC Manufacturing Services SiC JBS diodes, BJTs, and MOSFETs presently fabricated at XFAB Leverage Existing investment In Capital Equipment. Leverage an existing highly trained workforce Benefit from existing experience in offering qualified products Increase yield from implementation of quality control. X-FAB SiC Users: ABB, GeneSiC, Monolith, NCSU, USCi

9 Mission Summary X-FAB Installs Full SiC Processing Equipment Capability in Collaboration with PowerAmerica SiC Specific Equipment Purchased/Installed in Collaboration with PowerAmerica High Temp Anneal Furnace Centrotherm SiC Backgrind Tool Disco DFG8830 Backside Metal Deposition Tool AMAT Endura Backside Laser Anneal Tool IPG IX-6100 Maximum Temp: 1950C Installed Oct 2015 Capable of thinning to 175um Installed May chamber tool (Ti/Ni/Ag) Tool installed May 2015 Backside ohmic contact Installed Jan 2016 High Temp Implanter Max Implant Temp: 700C Installation Oct K 5K 150mm SiC wafers/month installed capacity Fab capacity: ~ 30K wafers/month (room to expand) Currently running 15K to 18K wafers/month of Si Able to increase SiC capacity as market grows

Mission Summary X-FAB Realizes Efficient Manufacturing through Consolidated Si/SiC Fabrication X-FAB / PowerAmerica Manufacturing

tools to run both Si and SiC wafers. Maximize equipment utilization. Operators run both Si and SiC. Maximize labor efficiency.

Scalability through Integrated Manufacturing Additional tools can be converted as SiC demand grows.

10 Mission Summary X-FAB Realizes Efficient Manufacturing through Consolidated Si/SiC Fabrication X-FAB / PowerAmerica Manufacturing Vision Open SiC Foundry fully integrated within a high volume 150mm Si fab Efficiency through Integrated Manufacturing Converted Si tools to run both Si and SiC wafers. Maximize equipment utilization. Operators run both Si and SiC. Maximize labor efficiency. SiC and Si share manufacturing and quality systems. SiC and Si share overhead. Maximize shared economies of scale. Scalability through Integrated Manufacturing Additional tools can be converted as SiC demand grows. Additional human resources can be trained for both Si and SiC production as demand grows for SiC. Consolidated Economies of Scale Aggregated SiC production efficiencies. Aggregated SiC epiwafer purchasing.

fabrication dominated by fixed O/H costs (Management, Quality, EHS, IT)

11 Mission Summary X-FAB Exploits Existing Si Economy of Scale to Reduce SiC Manufacturing Cost SiC Foundry at the Economy Scale of Silicon Wafer fabrication dominated by fixed O/H costs (Management, Quality, EHS, IT) Economies of scale the greatest factor in reducing cost Use the scale established in Si to accelerate SiC

12 Mission Summary X-FAB Customer Base Increases Through its Open SiC Reduced Manufacturing Cost Offering 43 Si tools converted to handle both Si and SiC wafers

13 PowerAmerica Mission has Summary Established Baseline Processes for 1200 V MOSFET and Diode SiC Fabrication at XFAB 1.2 kv MOSFET process by NCSU Dr. Jay Baliga and SUNY Dr. Woongje Sung Source Metal Inter layer dielectric P+ohmicN+ohmic Poly-Gate P+source N+source Channel P-body Drift Layer N+Substrate Drain Metal JFET region Mask Process steps Description Wafer N-/N+ substrate 1 Alignment Mark SiC Etch 2 P-base implant Oxide dep. Photo, Oxide etch Al implant, HT 3,4,5 N+, P+, JTE implant module Activation Anneal Gate Oxide 6 Gate Poly dep. Photo, Etch Std process 7 Oxide dep., Photo, CT Etch Std process 8 Ohmic, Schottky metal 9 Top Metal, B/S Metal Std process Unit cell schematic of PA MOSFET (not to scale) 10 Polyimide Std process 10 Mask MOSFET process includes 4 implant steps

14 The Mission PowerAmericaSummary Baseline 1.2 kv SiC MOSFET has an Active area of 4.5 mm 2 and an R ds,on of 5.5 mω-cm 2 The PowerAmerica process yielded 1.2 kv MOSFETs in its first run 9 MOSFET Id-Vd, Active area 4.5 mm 2 Drain Current (A) Vg=25V Vg=20V Vg=15V Vg=10V Vg=5V Vg=0V Drain Current (A) 9.00E E E E E E E-05 PiN MOSFET (Vgs=0V) E E E Drain Voltage (V) Drain Voltage (V) Specific on resistance: 5.5 mω-cm 2 at 1 A, Vg=20V BV 1400V, Id@1200V=1uA

15 The Mission PowerAmerica Summary Baseline 1.2 kv SiC MOSFET has a Threshold Voltage of 2.8 V MOSFET Id-Vg 25 C 0.05 Linear scale E-01 Log scale Drain Current (A) Id gm Gm Drain Current (A) 1.E-02 1.E-03 1.E-04 1.E-05 1.E-06 1.E-07 1.E-08 Id gm Gm E Gate Voltage (V) Gate Voltage (V) Threshold Voltage: 2.8 Id = 1mA

Schottky diodes with best-in-class performance and reliability at X-FAB s 150-mm SiC

16 Monolith Mission Semiconductor Summary Develops High yielding 1200 V Schottky process at X-FAB Objective: Develop manufacturable, high yielding and low-cost 1200 V SiC Schottky diodes with best-in-class performance and reliability at X-FAB s 150-mm SiC foundry. Current (A) 1200V, 10A Diode Reverse Leakage Current (A) Voltage (V) Voltage (V)

Objective: Qualify 150-mm Si foundry for SiC processing ABB Processes SiC

yields (testing underway) Pathways determined for cost reduction in future

17 ABB Mission Fabricates 3.3 Summary kv SiC Schottky Diodes and MOSFETs on 150-mm Wafers at X-FAB Objective: Qualify 150-mm Si foundry for SiC processing ABB Processes SiC diodes and MOSFETs on 150 mm SiC wafers for the first time: Process routers developed in collaboration with XFAB 3.3 kv rated SiC Schottky and MOSFET wafers fully processed with encouraging yields (testing underway) Pathways determined for cost reduction in future volume manufacturing Next Steps: Test a statistically relevant number of dies to evaluate yield/performance Schematic cross section of 3.3kV SiC JBS diode Top view of a 3.3kV SiC JBS diode wafer in process

USCi Mission Fabricates Summary 1200 V Planar MOSFETs on 150-mm Wafers at X-FAB

lower than target On-state behavior looks good Basic TO247 Rel test data looks

duration sample size status HTGB VGS=+20V, VDS=0, Ta=150C 1000hrs 77 Pass HTGBR

18 USCi Mission Fabricates Summary 1200 V Planar MOSFETs on 150-mm Wafers at X-FAB Objective: Develop 40mOhm, 1200V planar MOSFET Breakdown values on target Vth lower than target On-state behavior looks good Basic TO247 Rel test data looks good see table Basic Switching and UIS tests look good Test stress condition duration sample size status HTGB VGS=+20V, VDS=0, Ta=150C 1000hrs 77 Pass HTGBR VGS=-10V, VDS=0, Ta=150C 1000hrs 77 Pass HTRB VDS=960V, VGS=0, Ta=150C 1000hrs 77 Pass

Wolfspeed Foundry Fabricates 3.3 kv/40 mω Mission Summary SiC MOSFETs and 10 kv/15 A SiC JBS Diodes Objective: Qualify 3.3 kv/40 mω MOSFETs and 10 kv/15 A SiC JBS Diodes 8.86 mm 4.

19 Wolfspeed Foundry Fabricates 3.3 kv/40 mω Mission Summary SiC MOSFETs and 10 kv/15 A SiC JBS Diodes Objective: Qualify 3.3 kv/40 mω MOSFETs and 10 kv/15 A SiC JBS Diodes 8.86 mm 4.82 mm Leakage Current (µa) kv/40 mω SiC MOSFET Die Hours % Passed 1000 hr HTRB at 175 C & 2.64 kv (80% 3.3 kv) 6.2 mm 8.10 mm 8.10 mm 6.2 mm 10kV/20A SiC JBS Diode 100% Passed 1000 hr HTRB at 175 C & 8 kv (80% 10 kv)

Power Module First released at PCIM 2015.

20 Wolfspeed Mission Develops Summary 3.3 kv SiC Module with Customizable Device Configuration Objective: Develop 3.3 kv SiC Modules Module Manufacturing Improvements Demonstrate Process Automation New Equipment Installed & Operational Improve Process Yield Substrate & Die Attach Automate Verification Testing Sequential Room Temperature and High Temperature End of Line Testing In-Place Optimized Module Commercialization HT-4201: 1200V / 25 mω Full-Bridge SiC Power Module First released at APEC Samples Fielded. Initial Qualification Tests Completed. HT-3231: 1700V / 8 mω Half-Bridge SiC Power Module First released at PCIM Samples Fielded. Initial Qualification Tests Completed. Gate Drivers, Datasheets, & CAD Models Available Medium Voltage SiC Packaging & Application Support 3.3 kv SiC Module Designed with Customizable Device Configuration Companion Form Factor Gate Driver + Power Supply Samples Being Fielded to Early Customers Datasheets & CAD Models Available

21 John Mission Deere Electronic Summary Solutions is Developing WBG Power Electronics with PowerAmerica Support Objective: Develop a SiC inverter for the JD 644K Hybrid Loader JD 644K Hybrid Loader SiC Inverter Deployed in the JD 644K Hybrid Loader

22 John Mission Deere Hybrid Loader s Summary SiC Inverter has Performance Advantages over Conventional Si-IGBT Inverters Advantages of SiC Inverter > 17 kw/l power density as compared to < 9kW/L IGBT inverter Up to 25% more work per gallon fuel as compared to a conventional JD 644K Loader Suitable for engine coolant operation > 95% efficiency as compared to < 95 % efficiency with IGBT inverter Systems benefits and advantages: Reduction in engine size as compared to a conventional JD 644K Loader Less fuel consumption during idling Elimination of frequent refueling as compared to a conventional 644 Loader Cost savings: Elimination of inverter coolant loop and inverter operation with engine cooling system JD 644K Hybrid Loader

Toshiba Mission SiC MOSFET/diode Summary

23 Toshiba Mission SiC MOSFET/diode Summary based Commercial PV Inverter Exhibits Higher Efficiency and Lower Weight Objective: Build SiC MOSFET/diode based 50 kw commercial PV inverter prototypes. Achieve higher efficiency and lower weight. SiC MOSFET and diode TO-247 mounted on power board SiC MOSFET and diode TO-247 soldered onto metal-core PCB Peak Efficiency: 98.39% CEC Efficiency : 98.2% DC/DC Prototype I DC/DC Prototype II Weight of 50 kw PV inverter : lbs. / kg DC/AC Prototype I DC/AC Prototype II

NCSU Mission SiC Based Summary Fast Charger has Weight,

modular medium voltage Fast Charger using commercial

50 kw, 1200 V MOSFETs and diodes 2,400 Vac to 400 Vdc η

98, THD 2% 10x size reduction 4x weight reduction

24 NCSU Mission SiC Based Summary Fast Charger has Weight, Volume, and Efficiency Advantages Objective: Develop a modular medium voltage Fast Charger using commercial 1200 V SiC MOSFETs/diodes. 50 kw, 1200 V MOSFETs and diodes 2,400 Vac to 400 Vdc η 95%, PF 0.98, THD 2% 10x size reduction 4x weight reduction Simple install w/o step-down transformer MV Fast Charger V = 81.5 L m = 60 kg η 95% Commercial Fast Charger V = 1200 L m = 400 kg η ~ 93.5%,

NCSU Mission SiC High Fundamental Summary

Results Thermal image of the converter 5kV

switching line voltage (5 kv/div) 3kV DC

25 NCSU Mission SiC High Fundamental Summary Frequency 3-phase Converter Utilizes 15 kv IGBTs and 10 kv MOSFETs Converter Schematic Converter waveforms Experimental Results Thermal image of the converter 5kV DC bus, 400Hz Fundamental frequency, 10kHz switching frequency, 3.7kW load Load currents (5 A/div) Converter switching line voltage (5 kv/div) 3kV DC bus, 1000Hz Fundamental frequency, 20kHz switching frequency, 1.45kW load

University-Industry Mission Summary Collaborate to Characterize 10 kv - 10A SiC Module

10A Double pulse test (Tc = 150 C) SiC JBS diode Version 1 gate driver APEI Co-pack Module

Experimental data Switching voltage: 6kV Switching current: 10A Gate resistance: 15 ohms

26 University-Industry Mission Summary Collaborate to Characterize 10 kv - 10A SiC Module (NCSU-Wolfspeed) Objective: Evaluate Wolfspeed 10 kv- 10 A MOSFET Module APEI SiC MOSFET 10kV, 10A Double pulse test (Tc = 150 C) SiC JBS diode Version 1 gate driver APEI Co-pack Module Turn-off characteristic 4mH inductors Experimental test setup APEI co-pack module Case temperature ( C) Thermal Stability Test Temperature profile: 6kV, 5.3 A peak, 10kHz Time (min) Turn-on characteristic Experimental data Switching voltage: 6kV Switching current: 10A Gate resistance: 15 ohms Base-plate temperature: C Turn-off rate of rise of voltage: 28.7 kv/μs Turn-off energy loss: 2.2 mj Turn-on rate of rise of voltage: 68.6 kv/μs Turn-on energy loss: 9.9 mj

27 PA Mission Provides Value Summary to Members by Accelerating their WBG Concept to Prototype Cycle PA facilitates members with: Device design to member s specifications and applications. PA fabrication processes that can be tailored to member s devices. Access to fab PDK. Fabrication at X-fab and/or other WBG manufacturing centers. Testing/reliability, and custom reliability development. Packaging solutions and custom package design to member s temperature and voltage ratings. Circuit and module design to member s device and specifications. Module assembly and reliability testing. Failure analysis to drive device/circuit/module/system optimization. Workforce training (design, fab, test, reliability, packaging, circuit design, module, system) to accelerate member s product introduction to market. Consulting by WBG experts. Access to WBG ecosystem for market direction, industry perspectives, networking opportunities, problem solving, and gaining confidence in a new technology. Ability to influence shared project undertakings within PA. Highly WBG trained personnel (graduate students/post-docs) to strengthen member s workforce. The overall benefit of accelerated WBG product introduction to market. PA industry members grow their business by accelerated WBG product introduction to market PA University members gain by collaborating with industry

28 PA Mission Issued an RFI Summary to Guide an Early September 1:1 Cost Match Funding Solicitation RFI Topic Areas Include ( Topic 2: Foundry and Device Development US Silicon Carbide Merchant Foundry Infrastructure Development that leverages existing high-volume 150 mm or 200 mm silicon device fabrication. A good candidate for the Foundry will be one that currently has a profitable business model manufacturing commercial Si parts so that SiC power devices may be fabricated on the same line. A limited capital equipment budget may be available to assist in buying SiC specific process equipment. SiC Power Devices and Process Development (TRL 4) in a commercial SiC foundry in the US. This process development should be geared towards releasing a product (Engineering or Commercial release) within 12 months. Universities can team with foundries and companies to develop fabrication processes. Topic 3: Packaging, Power Electronics Foundry, Test & Reliability SiC power device module and gate-drive development and manufacturing Reliability, testing, and failure analysis of commercial SiC devices. Topic 4: Wide Bandgap Semiconductor Power Electronic Applications Transportation (Electric and hybrid vehicles, rail, power heavy electric vehicles, vehicle chargers, more electric aircraft, electric ship, space, etc.) Renewable Energy (Photovoltaics, wind applications, grid-tied energy storage, etc.) Power grid, power quality, fault protection, and uninterrupted power supplies Industrial motor drives Enterprise equipment, data center, power supplies Medium and high voltage testbed development ( kv)

30 SiC device based Small Commercial PV inverter Real market, Real value proposition from SiC devices, Real customer demands Competitor Landscape Specification from Customers 30

31 High Voltage DC Power Supply for Medium Voltage Gate driver DC Power Supply 15 kv Single galvanic isolation based transformer (Cp = 1.43 pf) Double galvanic isolation based transformer (Cp = 0.52 pf)

Intelligent Gate driver for Medium Voltage

switch circuit Differential sense amplifiers

driver validation: Boost-buck setup * 50%

32 Intelligent Gate driver for Medium Voltage Converters Intelligent Gate Driver (IMGD) Active gating and protection circuit Dynamically changing effective gate resistance during module switching Gate-voltage level reduction Using a shunt switch circuit Differential sense amplifiers Short Circuit Protection at 3kV DC bus Gate driver validation: Boost-buck setup * 50% duty of Buck converter * 25% duty of Boost converter * Boost input is 1.25kV Output is 5kV * Buck converter switch is now at higher potential so that its IMGD gets 5kV pulsating stress

Semicon West San Francisco, CA July 12, 2016 Dr. John Muth

Semicon West San Francisco, CA July 12, 2016 Dr. John Muth muth@ncsu.edu 1 National Network for Manufacturing Innovation Flexible Electronics Digital Manufacturing and Design Innovation Lightweight and