A novel lateral superjunction Ga2O3 MOSFET with a self-biased accumulation layer for ultra-low specific on-resistance and improved FOM

Abstract In this article, a high-performance enhancement-mode (E-mode) lateral superjunction β-Ga2O3 metal-oxide- semiconductor field-effect transistor (MOSFET) incorporating a self-biased p-type nickel oxide (NiO) layer was proposed and numerical investigated. The drift region of the proposed lateral superjunction Ga2O3 MOSFET includes n-type Ga2O3, Al2O3 and p-type NiO layers. The electric field distribution and specific on-resistance of the drift region both are greatly improved, due to the compensation effect n-type Ga2O3 and p-type NiO superjunction drift layers. Additionally, the p-type NiO layer is self-biased with a voltage of ～14.3V, to form an accumulation layer in the drift region, which further reduces the specific on-resistance (Ron,sp) of the device. Simulation results indicated that the proposed device achieves a breakdown voltage (BV) of 7000V and Ron,sp of 17.73 mΩ·cm². In contrast, the conventional device with the same drift region length has a BV of 3500V and Ron,sp of 162.58 mΩ·cm². The figure of merit (FOM) values for the proposed and conventional devices were 2.76 GW/cm² and 75.34 MW/cm², respectively, representing a 3565% improvement. The combination of superior device performance and a straightforward manufacturing process presents a promising outlook for the application of the proposed device.