SBIR/STTR Award attributes
The efficiencies of Electric Vehicle (EV) and Hybrid Electric Vehicle (HEV) need to be improved in order to reduce reliance on hydrocarbon fuel-based transportation systems and thus reduce CO2 emissions. For this to happen, high voltage onboard power electronics need to be greatly improved in terms of performance and cost. Currently, vehicle power electronics predominantly utilize silicon-based power semiconductors switch technology based on MOSFET, and IGBT devices. Silicon power semiconductor devices have several limitations including high losses relatively low bandgap, low electrical field breakdown requiring very thick material growth for high voltage operation which results in high resistance and associated conduction losses. GaN based devices are believed to be the best solution to this problem. The problem can be addressed by replacing silicon-based devices with the wide band gap (WBG) semiconductor (Silicon Carbide (SiC) and Gallium Nitride (GaN)) devices. The WBG d semiconductors devices are much more efficient (lower on resistance and higher frequency operation) and can withstand higher temperatures than Si components. Hence, devices made of WBG semiconductors could decrease system costs by reducingthe requirements for complex thermal management systems. In Phase I project the issues related to the economical production of uniform high quality GaN device materials on large area substrates (4 inches and beyond) will be addressed by designing tools to grow desired devices on large area substrates and by developing the efficient power devices that deliver desired at high currents (>20A) and higher voltages (>600V); however, their production costs remains high and need to be reduced. The GaN devices are required for EVs and EHVs, telecommunications, industrial, automotive, renewables, consumer and enterprise, military, defense, and aerospace and medical applications. The GaN devices have broad commercial applications for making efficient SMPS (Consumer chargers & adapters), EV, EV chargers & battery management, Cleantech (solar, battery chargers), UPS, motor control, small electric mobility systems (bikes, scooters, skateboards or other similar systems), wireless power transmission, and audio amplifications, among many other applications.
