Simulation Research on High-Voltage β-Ga₂O₃ MOSFET Based on Floating Field Plate

Abstract

A simulation model of a depletion-mode (D-mode) β-Ga2O3 metal–oxide–semiconductor field-effect transistor (MOSFET) was constructed by Silvaco ATLAS technology computer-aided design (TCAD) simulation, which employs an epitaxial drift layer grown on a sapphire substrate. On this basis, the floating field plate (F-FP) structure based on the gate-pad-connected field plate (P-FP) was proposed to improve the breakdown characteristics of the device, which was easily prepared. The working principle of F-FP was investigated with the help of the device with one F-FP, based on the principle that the number of floating field plates increases on an optimized floating field plate structure. Subsequently, the devices with two and three floating field plates were simulated in turn, and the optimal structural parameters of the three F-FPs device were finally obtained, and the breakdown voltage was 3800 V. In addition, it was found that the device breakdown voltage increased by approximately 500-600 V for each additional floating field plate.