Operating Principles, Design Considerations, and Experimental Characteristics of High-Voltage 4H-SiC Bidirectional IGBTs

Bidirectional power transistors are essential components of several power electronics systems, such as matrix converters. In this paper, we present the operating principles, design considerations, and experimental characteristics of a novel planar gate 4H-SiC bidirectional insulated gate bipolar transistors. The impact of various drift layer and unit cell parameters on blocking, on-state, and switching performance has been evaluated by using numerical simulations, and critical performance tradeoffs have been discussed. Based on the optimized design, devices were fabricated on lightly doped free-standing n-type 4H-SiC wafers. Fabricated devices showed good conductivity modulation, with a forward voltage drop of 9.7 V at 50 A/cm ² at room temperature, which increased to 11.5 V at 150 °C.