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

Abstract

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/cm 2 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.

Investigations of 4H‐SiC trench MOSFET with integrated high‐K deep trench and gate dielectric

“…One method is to apply HK dielectric material in the drift region of TMOS. In [12], a structure is proposed where a HK dielectric region alternates with the drift region laterally. This arrangement increases the electric field strength at the interface, resulting in a more uniform overall electric field distribution and higher BV [12][13][14][15].…”

“…In [12], a structure is proposed where a HK dielectric region alternates with the drift region laterally. This arrangement increases the electric field strength at the interface, resulting in a more uniform overall electric field distribution and higher BV [12][13][14][15]. Another method is to replace the gate dielectric of TMOS with an HK dielectric material [16][17][18].…”