Degradation of Power SiC MOSFET under Repetitive UIS and Short Circuit Stress

Abstract

This paper investigates the reliability of commercial planar and trench 1.2-kV 4H-SiC MOFSETs under repetitive unclamped inductive switching (UIS) and short circuit (SC) stresses. The degradation of device characteristics, including the transfer characteristics, drain leakage current Idss, and output characteristics, is observed. Repetitive SC stress was performed for 400 and 600 V bus voltages. Increased buss voltages during stress have higher impact on electrical performance of tested devices. The hot carriers injection and trapping into the gate oxide in the channel region may occur during the aging experiments and are believed to be responsible for the variation of electrical parameters.