Body Diode Reliability of Commercial SiC Power MOSFETs

Abstract

Stacking faults in the drift layer of 1.7 kV 4H-SiC MOSFETs result in body diode degradation, poor carrier conduction in on-state, and high leakage current in off-state. In this paper, the results of forward-bias stress on body diodes are analyzed in commercially available 1.7 kV 4H-SiC MOSFETs. Some devices show a significant degradation after forward-bias stress on the internal body diode. This implies that there are significant number of Basal Plane Dislocations (BPDs) present in these devices. These BPDs may be originally present in the drift layer or they may be induced by processing such as room temperature ion-implantation.