Investigation of Maximum Junction Temperature for 4H-SiC MOSFET during Unclamped Inductive Switching Test

Abstract

Normally, thermal breakdown is one of the serious failure phenomena in the power device application, which drives the researchers to focus on exploration of the failure mechanism and the new evaluation method for power device. In this paper, unclamped inductive switching (UIS) test is presented to evaluate energy handing ability and maximum junction temperature of 1200V/19A SiC MOSFET during avalanche mode. It is verified that commercial 1200V/19A SiC MOSFET can easily withstand almost ten microseconds avalanche time and around 924 K maximum junction temperature with 1 mH inductance and 400 V DC bus at the case temperature of 300 K in avalanche mode. In addition, three reasonable evaluation methods of the maximum junction temperature for SiC MOSFET are summarized at different case temperatures.