SiC trench MOSFET with integrated side-wall Schottky barrier diode having P⁺ electric field shield

Abstract

A new SiC trench MOSFET (T-MOSFET) integrated with a side-wall Schottky Barrier Diode (SBD) to form a compact power device is proposed. The proposed structure applies two trenches to form the n-channel and SBD in a single cell, respectively. A P⁺ is implanted after etching the trenches to form a shield for both the gate oxide and the Schottky barrier. The breakdown voltage of the proposed one is about 363% larger than that of the conventional trench MOSFET (CT-MOSFET) with integrated SBD. The integrated SBD of the proposed T-MOSFET exhibits an ultra-low leakage current (1 µA/cm²) and low forward voltage drop (V_{on_diode} ≈ 0.9 V), as well as low reverse recovery charge (Q_rr = 0.73 µC/cm²).