Thermal Dynamic of Single-Event Burnout in SiC Power MOSFETs

Single-event burnout (SEB) poses a significant threat to silicon carbide (SiC) MOSFETs when operating in aerospace environments, resulting in permanent functional failures of the device and system-level risks through ion-induced thermal runaway effects. However, the detailed thermal response process and triggering mechanism remain inadequately understood. In this study, a novel current-limiting method was used to investigate the SEB damage evolution process and mechanism in SiC MOSFETs. Experimental results show that the SEB events can be divided into three distinct stages: initial damage at the p-n-junction, followed by a shift to the source metal/SiC corner, where lattice eutectic triggers intensified p-n-junction degradation, and final burnout when the n-n-junction reaches SiC sublimation temperature. Subsequent simulation results show that the current crowding effect at the SiC surface and avalanche breakdown at the n-n-junction are critical contributors to the SEB process. The findings provide useful insights into understanding the ion-induced catastrophic phenomena in SiC power devices.