Demonstration of 3 kV 4H-SiC reverse blocking MOSFET

The authors developed 3 kV 4H-SIC reverse blocking (RB) metal-oxide-semiconductor field-effect transistors (MOSFETs) for the first time. To achieve reverse blocking capability, the n+-substrate layer was removed by polishing, and both a Schottky contact and edge-termination structure were introduced onto the wafer backside. Fabricated SiC RB MOSFETs exhibited good Schottky characteristics, and measured differential specific on-resistance was 20 mΩ·cm2. Both forward and reverse blocking voltages of RB MOSFETs are higher than 3 kV. On-state power loss of a developed RB MOSFET is 35% lower than that of anti-serially connected standard 3 kV SiC MOSFETs, demonstrating the advantage of the developed RB MOSFET as a high-voltage bi-directional switch.