Dynamic Gate Stress Induced Threshold Voltage Drift of Silicon Carbide MOSFET

Abstract

For silicon carbide (SiC) power MOSFETs, threshold voltage drift is a remaining obstacle in their way to the market. This study experimentally investigates the drift under dynamic or switching gate stresses. It is shown that, beside static stress, the switching events can themselves be a driving force of the threshold voltage drift. However, this happens only when the dynamic gate stress is bipolar. The study extends to show that the dynamic stress induced drift can be sustained. The findings can be used in further work for managing and coping with the threshold voltage drift in device applications.