Gate Current Peaks Due to CGD Overcharge in SiC MOSFETs Under Short-Circuit Test

SiC MOSFETs experience a wide variety of electro-thermal phenomena during short-circuit (SC) test. A specific feature that is present in SiC MOSFETs is the high dynamic gate current (i
G
) which may have an influence on device degradation and failure. In recent SiC MOSFET technologies, the i
G
waveforms captured during SC testing show previously unexplained peaks. In this paper, the authors investigate the causes of these i
G
peaks using both experimental data and TCAD simulations, where significant effects of the C
GD
overcharge are observed. Moreover, an i
G
comparison between different 1.2 kV device designs are performed with emphasis on best i
G
sensing practices.