A New Vertical p-GaN Island Double-Trench MOSFET with High Voltage Resistance and Low Leakage

Abstract

Due to the higher breakdown voltage (V_DSmax) and anticipated improved reliability, vertical gallium nitride (GaN) metal-oxide-semiconductor field-effect transistors (MOSFETs) are a focal point in next-generation power device research. This paper, based on DC characteristic simulations of various trench-structured GaN MOSFETs, proposes a novel p-GaN island double-trench MOSFET (P-Island DT-MOS) device. Compared to single-trench MOS devices with identical structural parameters, the double-trench structure of this device achieves a lower peak electric field in the oxide layer. Furthermore, the incorporation of the p-GaN island enhances V_DSmax to 1.74 kV. Due to the reduced gate-drain charge in the P-Island DT-MOS, its high-frequency figure of merit (HF-FOM) is 47 % lower than that of the DT-MOS. The findings of this study are significant for achieving high breakdown voltage and low on-resistance in vertical GaN double-trench MOS devices.