4H-SiC V-Groove Trench MOSFETs with Low Specific On-State Resistance and High Reliability

Abstract

The originally structured 4H-SiC V-groove trench MOSFET with {0-33-8} face for the trench sidewalls has been proposed. The inclined trench structure can be fabricated by the thermochemical chlorine etching, resulting in the smooth low damage surface. Consequently, the low specific on-state resistance of the VMOSFET was attained. Thus a large current of 150A was obtained with a single 6-mm-square chip. High Temperature Gate Bias (HTGB) test was performed under a gate bias of +20V or -10V at 175oC. After the 2500 hour test, the threshold voltage kept stable only within ±0.2 V voltage shifts. Due to these advantages, the VMOSFETs are suitable for use in automotive electronic devices and the regenerative energy generation system applications.