Simulation Study of 4H-SiC High-k Pillar MOSFET With Integrated Schottky Barrier Diode

A SiC high-k (HK) split-gate (SG) MOSFET is proposed with a Schottky barrier diode (SBD) integrated between the split gates, and is investigated by numerical TCAD simulation. Results show that it has the same breakdown voltage as the SiC high-k (HK) MOSFET with an optimized and practical k value of 30 for its insulation pillar, which results in the highest breakdown voltage (1857 V). The forward voltage (VF) and reverse recovery charge (QRR) of the device are 0.9 V and 3.49 μC/cm2 respectively, much lower than those of the SiC HK MOSFET due to the SBD. Moreover, lower reverse transfer capacitance (CRSS), smaller gate charge (QG), and smaller gate-to-drain charge (QGD) are achieved for the proposed device because of the split-gates, leading to much lower switching power loss when compared with the SiC HK MOSFET. All these results indicate that the SiC HK SG-MOSFET has promising potential in future power electronics applications.