| Summary: | A novel split-gate SiC MOSFET with an embedded MOS-channel diode for enhanced third-quadrant and switching performances is proposed and studied using TCAD simulations in this paper. During the freewheeling period, the MOS-channel diode with a low potential barrier constrains the reverse current flow through it. Therefore, the suggested device not only has a low diode cut-in voltage but also entirely suppresses the intrinsic body diode, which will cause bipolar deterioration. In order to clarify the barrier-lowering effect of the MOS-channel diode, an analytical model is proposed. The calibrated simulation results demonstrate that the diode cut-in voltage of the proposed device is decreased from the conventional voltage of 2.7 V to 1.2 V. In addition, due to the split-gate structure, the gate-to-drain charge (<i>Q</i><sub>GD</sub>) of the proposed device is 20 nC/cm<sup>2</sup>, and the reverse-transfer capacitance (<i>C</i><sub>GD</sub>) is 14 pF/cm<sup>2</sup>, which are lower than the <i>Q</i><sub>GD</sub> of 230 nC/cm<sup>2</sup> and the <i>C</i><sub>GD</sub> of 105 pF/cm<sup>2</sup> for the conventional one. Therefore, a better high-frequency figure-of-merit and lower switching loss are obtained.
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