A Novel Split-Gate-Trench MOSFET Integrated With Normal Gate and Built-In Channel Diode

Abstract

A novel split-gate-trench MOSFET integrated with normal gate and built-in channel diode (BCD) in the same trench is proposed and simulated with Sentaurus TCAD in this paper. Compared with the conventional SGT MOSFET (C-SGT MOS) and conventional SGT MOSFET with built-in channel diode (CBCD-SGT MOS), the proposed MOSFET exhibits superior performances, such as smaller turn-on voltage and lower reverse recovery charges when working in the third quadrant, and reduced gate charge and gate-to-drain charge when working in the first quadrant. With the negligible degradation of the on-state resistance, significant improvements in the figures of merit can be obtained. What’s more, obvious uniform forward and reverse conduction current distribution of proposed structure is observed compared to CBCD-SGT MOS although two types of devices are both featuring BCD structure, which could increase the robustness of device when working in high-power and high-frequency applications.

Keywords

• Split-gate-trench MOSFET
• built-in channel diode
• reverse recovery characteristics
• figure of merit
• current distribution