Wide bandgap semiconductor technologies provide significant advantages for the development of power electronic devices and modules. In particular, silicon carbide (SiC) technology offers improved electrothermal performance and size, weight, and power (SWaP) savings for higher power/higher voltage applications, along with cost benefits that are derived from a well-established device and material technology. Both NASA and the DoD have multiple ongoing programs to design, characterize, and develop SiC-based power electronics for their upcoming missions. However, high susceptibility to heavy-ion radiation induced degradation and catastrophic failure is a barrier for utilizing this technology in high-altitude and space power applications. Physical mechanisms for this susceptibility are not well understood, resulting in the unavailability of radiation-tolerant SiC devices. In this SBIR, the CFDRC team is applying a coupled experimental and physics-based modeling approach to address this challenge. In Phase II, we implemented physics and numerical models in CFDRC’s NanoTCAD software for accurate simulations of SiC JBS diodes. We performed an extensive modeling-based investigation of the available design space to identify the key parameters for improved heavy-ion tolerance. Design guidelines were provided to Wolfspeed and new device variants were fabricated for testing. In Phase II-E, we will focus on further co-development of guidelines for electrical and radiation performance, and investigate trade-offs to achieve radiation tolerance up to a higher operating voltage. This, in turn, will yield a larger safe operating area (SOA) for the SiC diodes. Completion of the Phase II-E project will enable us to raise the technology readiness level and support transition of this technology into power management and distribution (PMAD) systems being developed for NASA, Army, other US Government agencies, and commercial programs.

Radiation tolerant, high voltage/high power SiC power electronics can lead to lower PMAD system weight, and is an enabling technology for realizing operational concepts such as solar electric propulsion, and lunar and planetary surface power systems. It supports Technology Taxonomy TX03 (Aerospace Power and Energy Systems) and TX08 (Sensors and Instruments). The developed modeling and analysis tools will be a Cross-Cutting Technology that provides capability to all NASA missions that require power electronics.

Radiation tolerant SiC power electronics are applicable in DoD space systems (communication, surveillance, missile defense), Army air platforms (rotorcraft, drones), commercial satellites, and nuclear power systems. SiC-based high-voltage power converters and motor drives are promising for all-electric and hybrid cars, grid-scale energy storage systems, military ground vehicles, etc.