Line-shaped defects: Origin of leakage current in halide vapor-phase epitaxial (001) β-Ga2O3Schottky barrier diodes

Abstract

We observed line-shaped defects in halide vapor-phase epitaxial (001) β-Ga2O3 SBDs. Light emission patterns, representing the reverse leakage current, were observed at these line-shaped defects. In atomic force microscopy observations, the line-shaped defects appeared as grooves with a typical depth and width of 113 and 520 nm, respectively. Such defects corresponded to a leakage current of-0.23 μA at-200 V. Simulation results indicated that the electric field, with an intensity of 1.3 MV/cm, was highly concentrated at the bottom of the line defects. According to the cross-sectional scanning transmission electron microscopy analysis, the line-shaped defects were generated from a dislocation network beneath the crystal near the surface.