Investigation on Reliability of SiC MOSFET Under Long-Term Extreme Operating Conditions

To evaluate the aging state and the aging mechanisms of SiC MOSFET components, aging process under long-term extreme operating conditions (short circuit and unclamped inductive switching) has been performed. The study focuses on discrete SiC MOSFET (1.2kV-60A). We experimentally measure different aging indicators during the aging with several dissipated energies per cycle. The results highlight a similar evolution of these aging indicators measured in both test conditions. A very light increase in the gate leakage current (about 900 fA) has been detected before the device failure. This leakage current seems to be related to the degradation of the gate oxide layer.