Study on 4H-SiC Trench Gate Dual-Mode Composite Transistors (T-DCT) Structure to reduce R_on and Enhance SCWT

In order to solve of high specific on-resistance and limited short-circuit withstand capability of conventional 4H-SiC Vertical U-groove MOSFET (VUMOS), a Trench-gate Dual-mode Composited Transistor (T-DCT) structure with VUMOS and BJT in parallel is proposed. The static characteristics, switching behavior, and short-circuit robustness of the T-DCT are systematically evaluated by TCAD and compared with that of VUMOS. Simulation results show that the T-DCT achieves a 50% reduction in Ron while exhibiting enhanced short-circuit withstand time (SCWT) of 7.0μs, a 29.6% improvement compared to the 5.4μs SCWT of the VUMOS.