Effect of Dynamic Threshold-Voltage Instability on Dynamic ON-State Resistance in SiC MOSFETs

This work presents an investigation of several important phenomena related to threshold-voltage instability in SiC MOSFETs. Such instability can occur in previously unstressed as-processed devices, including trench-geometry devices, when exposed to a negative gate-bias overstress. This work also reports, for the first time for SiC MOSFETs, on the dynamic nature of ON resistance in the presence of large threshold-voltage instabilities, whether occurring in as-processed devices or due to an ac stress-induced degradation.