A Novel 4H-SiC/Diamond SuperJunction MOSFET With Self-Driving Electron Accumulation Layer Realizing Extremely Low R on,sp

In this letter, a novel 4H-SiC/Diamond SuperJunction (SJ) MOSFET with a Self-driving Electron Accumulation Layer (SD-EAL) in the drift region, named as SD-EAL MOSFET, is proposed and investigated based on experimentally calibrated TCAD simulations. The SJ structure comprising n(4H-SiC)/Al₂O₃/p(Diamond) is used for feasible fabrication and formation of EAL. An integrated self-biased low-voltage power formed by integrated JFET structure, PolySi PN diode and MIS capacitor is designed to automatically drive the p-pillar, thus forming an EAL during on-state and significantly reducing the specific on-resistance (R_on,sp). The simulated breakdown voltage (BV) of the SD-EAL reaches ~1.6 kV, with R_on,sp being only 0.75 mΩ·cm², which is 36% lower than that of conventional SJ (C-SJ). Compared to the C-SJ MOSFET, Figure of Merit for the SD-EAL MOSFET reaches 5.69 GW/cm², which is improved by 94%. Thus, the SD-EAL can be an excellent candidate for future high-voltage SJ MOSFET.