Breakdown Characteristics of $\beta$ -(Al_0.22Ga_0.78)₂O₃/Ga₂O₃ Field-Plated Modulation-Doped Field-Effect Transistors

Abstract

We investigate voltage breakdown of a beta-(Al0.22Ga0.78)(2)O-3/Ga2O3 modulation-doped field-effect transistor with a gate-connected field-plate and silicon nitride (SiNx) as the passivation layer. Breakdown characteristics were found to be limited by the Schottky gate. We demonstrate a high breakdown voltage of 1.37 kV for a gate-to-drain separation (L-GD) of 16 mu m with a specific ON-resistance of 120.1 m Omega.cm(2). A high average electric field of 3.9 MV/cm is extracted for LGD = 320 nm. The reported results suggest SiNx as a potential passivation dielectric for Ga2O3.