Effect of Termination Region on Unclamped Inductive Switching Failure for 4H-SiC VDMOS

The effect of the termination structure on the unclamped inductive switching (UIS) failure is analyzed for two kinds of SiC MOSFET, where S-MOS and G-MOS termination structure are adopted. The MOSFETs are named as S-MOS and G-MOS according to the buses connecting with different electrodes in the termination region. The experimental results indicate that the avalanche energy G-MOS can withstand is 1.15 times larger than that of S-MOS. To understand what are the factors that lead to different UIS capabilities, further static measurements and hotpot mapping after UIS test are done, and technology computer aided design (TCAD) simulation also is done to further confirm the principle.