Structure Analysis on the Short-Circuit Robustness for 1200V Planar SiC MOSFETs

Due to the material characteristics of silicon carbide (SiC), the SiC MOSFET robustness under extreme conditions is attractive for further investigation, especially under short circuit conditions. In this paper, 1200V planar SiC MOSFET devices were selected and investigated under TCAD simulation, focusing on the effect of P-base, P+region depth on the short- circuit robustness and analysis of failure mechanisms. First, short-circuit principle was reviewed, followed by the actual short circuit test set-up in the laboratory. Then, we build the current mainstream planar SiC MOSFET device model in TCAD, together with the short circuit simulation circuit according to the laboratory set-up. Finally, it was studied that the influence of the size of P-base region, P+region on the short-circuit performance of the device and concluded the common failure mechanism The work researched the influence of P-base and P+region design parameter influence on the short-circuit performance of planar MOSFET devices, so as to better assist the design for better robustness of SiC power MOSFETs.