High performance SiC trench-type MOSFET with an integrated MOS-channel diode

Abstract

A novel SiC double-trench metal-oxide-semiconductor field effect transistor (MOSFET) with integrated MOS-channel diode is proposed and investigated by Sentaurus TCAD simulation. The new SiC MOSFET has a trench gate and a stepped-trench source, and features an integrated MOS-channel diode on the top sidewall of the source trench (MT MOS). In the reverse conduction state, the MOS-channel diode turns on firstly to prevent the internal parasitic body diode being activated, and thus reduces the turn-on voltage V F and suppresses the bipolar degradation phenomena. The V F of 1.70 V (@I ds = –100 A/cm2) for the SiC MT MOS is 38.2% lower than that of SiC double-trench MOSFET (DT MOS). Meanwhile, the reverse recovery charge Q rr of the MT MOS is 58.7% lower than that of the DT MOS at I load = 700 A/cm2, and thus the reverse recovery loss is reduced. Furthermore, owing to the modulation effect induced by the double trenches, the MT MOS preserves the same superior forward conduction and blocking performance as those of DT MOS, with 22.9% and 18.2% improvement on breakdown voltage and R ON,sp compared to the trench gate MOSFET with planar integrated SBD (ST MOS).