SiC Trench MOSFET With Integrated Self-Assembled Three-Level Protection Schottky Barrier Diode

Abstract

A silicon carbide (SiC) trench MOSFET (TMOS) with integrated three-level protection (TLP) Schottky barrier diode (SBD), named ITS-TMOS, is proposed and investigated by simulation. The device features the integrated TLP-SBD that remarkably improves body diode characteristics while guarantees excellent fundamental performance of TMOS. In the blocking state, the P-base region, the trench gate, and the P+ shield at the trench bottom serve as the TLP of the Schottky contact. Each protection assists in depleting the drift region beneath Schottky contact. Benefiting from the self-assembled TLP, the leakage current of the integrated body diode of the ITS-TMOS is significantly reduced. Moreover, the reverse turnon voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> ) and the gate charge (Q <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> ) of the ITS-TMOS are 65% and 18% lower than those of the conventional TMOS, respectively. The improved overall performances make the SiC ITS-TMOS a competitive candidate for high-efficiency and high power density applications.