New Short Circuit Failure Mechanism for 1.2kV 4H-SiC MOSFETs and JBSFETs

The short circuit (SC-SOA) capability of power devices is crucial for power systems. In this paper, 1.2 kV SiC MOSFETs and JBSFETs are characterized, and their SC-SOA behavior was tested and analyzed. Due to the lower saturated drain current, the JBSFETs were found to have superior SC-SOA compared with MOSFETs despite the integrated Schottky contact. A new short circuit failure mechanism related to melting of the top Al metallization is proposed based up on non-isothermal TCAD numerical simulations supported with SEM measurements of failed die using Energy Dispersive X-ray Spectroscopy (EDS) analysis.