A Gate-Oxide Degradation Monitoring Method of SiC MOSFETs Based on Threshold Voltage Hysteresis

Silicon carbide metal-oxide-semiconductor-field-effect transistors (SiC MOSFETs) have excellent performance under high-temperature and high-power conditions. Gate-oxide degradation has long been one of the key reliability concerns of SiC MOSFETs. In this article, a new parameter that combines the on/off drain current change rate dins/dt is proposed for gate-oxide degradation monitoring to reduce temperature interference. It is based on the finding that the threshold voltage hysteresis of SiC MOSFETs changes significantly over gate-oxide degradation. The superiority of this method is validated by the double pulse test results.