Power electronics is critical for Navy and Marine Corps platforms and missions. The introduction of new weapons systems, new radars, and new sensors means that power needs are growing rapidly for platforms such as electric combat vehicles and the more-electric aircraft. Advanced power electronic converters offer significant advances in power density, efficiency, and reduced total life cycle cost. These converters are based on wide bandgap silicon carbide (SiC) and gallium nitride (GaN) power switching devices and their integration with diamond material layers for improved thermal conductivity.
Efficient High Voltage Silicon/SiC Hybrid Modules
ESTD has developed very efficient medium voltage power modules by replacing the traditional Si freewheeling diode with SiC Schottky diodes. The diodes have proven extremely reliable and are expected to be commercialized in the near future.

ESTD power electronics research is focused on wide bandgap SiC and GaN materials and devices. The high critical electric field for wide bandgap materials enables power electronic switches with operation temperatures greater than 200°C and with approximately 10x higher voltage and 10x reduction in on-resistance compared to silicon. These improved power electronic switch characteristics enable power converters with approximately 10x higher switching frequency, 5x lower volume, and 60-80% reduction in energy loss.

The ESTD Power Electronic program is a vertically integrated research program that provides significant synergy in correlating defects in SiC and GaN material with epitaxial growth approaches and device performance and reliability. Focus areas include:

SiC and GaN Epitaxial Growth Research: The advancement of wide bandgap devices is principally limited by defects within the wide bandgap substrate and epitaxial layers. A key research focus is developing epitaxial growth science to eliminate defects that degrade SiC and GaN device reliability, performance, and yield.

Characterization of Defect in SiC and GaN: Developing tools and techniques to characterize defects in wide bandgap substrates and epitaxial layers is a requirement for improving epitaxial growth approaches to eliminate defects. It is also necessary for correlating defects with device reliability, performance, and yield.

Development of Advanced SiC and GaN Power Device Processes: Research is focused on the development of novel device structures and the advancement in processing science for passivation, termination, contacts, and other critical device structures to improve device performance and reliability.

Reliability of SiC and GaN Power Devices: ESTD is developing unique tools and methods for characterizing and understanding failure mechanisms in SiC and GaN power devices so that devices can be improved and optimized.