Investigation of dVDS/dt Controllability on Rg in SWITCH-MOS to Achieve Superior Turn-on Characteristics with Low dVDS/dt

摘要

In this study, we investigated dVDS/dt controllability on gate resistance (Rg) in a 1.2 kV SWITCH-MOS. In the case of large Rg, the SWITCH-MOS showed roughly the same dVDS/dt as a conventional SiC trench MOSFET. However, in the case of small Rg, the SWITCH-MOS achieved higher dVDS/dt, suggesting that the SWITCH-MOS could improve the dVDS/dt controllability on Rg. In the SWITCH-MOS, negative dID/dt occurs in the initial phase of the drain-source voltage fall, owing to the fast reverse recovery. Therefore, the SWITCH-MOS has a large gate charging current in the initial phase, resulting in higher dVDS/dt with small Rg. In the case of large $R_{g}$, this negative dID/dt is so small that the SWITCH-MOS shows low dVDS/dt. Hence, the SWITCH-MOS demonstrates excellent dVDS/dt controllability on Rg.