Design of the Drift Layer of 0.6 – 1.7 kV Power Silicon Carbide MOSFETs for Enhanced Short Circuit Withstand Time

Abstract

We propose a simple technique of raising the short circuit withstand time (SCWT) of 0.6 - 1.7 kV SiC power MOSFETs, where the drift layer resistance is a small fraction of the on-resistance. Using simulations, we show that the SCWT of these devices can be raised by upto 20% by increasing the thickness and lowering the doping of the drift layer at the cost of only 5 % increase in the on-resistance. This approach also raises the breakdown voltage by > 10%.