A Novel Low-Voltage-Based Methodology for Short-Circuit Withstand Time Screening of Commercial 4H-SiC MOSFETs

With the rapid advancement of silicon carbide technology, device reliability has emerged as a critical concern for high-performance power electronics applications. Among various reliability challenges, the limited short-circuit withstand time (SCWT) of SiC MOSFETs, coupled with significant device-to-device variation, poses a serious risk, as it can lead to catastrophic field failures. In addition, established short-circuit screening technique utilizes high-voltage and high-stress condition that may degrade the long-term reliability of otherwise good devices. Hence, this work proposes a novel short-circuit screening methodology employing lower voltages and verifies it using commercial 1.2 kV 4H-SiC MOSFETs. The proposed approach can remove devices with lower SCWT while minimizing electrical and thermal overstress during screening. The results indicate that the proposed low-voltage screening technique offers a safe, repeatable, and reliable alternative to conventional short-circuit screening method, making it well suited for practical manufacturing, leading to system-level reliability enhancement in SiC-based power electronics applications.