Body PiN diode inactivation with low on-resistance achieved by a 1.2 kV-class 4H-SiC SWITCH-MOS

Integration of SBD into SiC-MOSFET is promising to solve body-PiN-diode related problems known such as forward degradation and reverse recovery loss. Particularly in lower breakdown-voltage-class SBD-integrated MOSFET, cell pitch reduction has a greater impact on inactivating the body-PiN-diode. Here, we developed a novel device called an SBD-wall-integrated trench MOSFET (SWITCH-MOS), in which small cell pitch of 5 mu m was realized by utilizing trench side walls both for SBD and MOS channel with buried p(+) layer. The fabricated 1.2 kV SWITCH-MOS successfully suppressed the forward degradation under extremely high current density condition with low switching loss, low specific on-resistance, and low leakage current.