【Device Papers】Plasma-power-driven recovery of dry-etch damage and barrier uniformity in β-Ga₂O₃ Schottky barrier diodes

      Researchers from Kwangwoon University have published a dissertation titled " Plasma-power-driven recovery of dry-etch damage and barrier uniformity in β-Ga₂O₃ Schottky barrier diodes " in Materials Science in Semiconductor Processing.

Abstract

      Dry etching is indispensable for the fabrication of β-Ga₂O₃ power devices, yet it introduces near-surface damage that deteriorates Schottky barrier uniformity and electrical performance. In this work, the influence of O₂ plasma power on the recovery of dry-etch-induced damage in planar β-Ga₂O₃ Schottky barrier diodes (SBDs) was systematically investigated. Following ICP-RIE etching, O₂ plasma treatment was carried out at 100, 200, and 300 W for 5 min prior to Ni/Au Schottky contact deposition. Among the investigated conditions, the sample treated at 200 W exhibited the best overall performance, with the lowest root-mean-square (RMS) surface roughness of 1.45 nm, compared with 4.19 nm for the as-etched sample. Dry etching increased the reverse leakage current density from 2.97 × 10⁻¹⁰ to 3.22 × 10⁻⁸ A/cm² and reduced the breakdown voltage (BV) from 530 to 490 V, whereas the 200 W plasma treatment effectively restored the reverse-blocking characteristics and improved the ideality factor to 1.42. Temperature-dependent analysis further revealed that the 200 W-treated device exhibited the smallest barrier-height inhomogeneity and the lowest interface-state density (N_SS), indicating the formation of the most uniform Schottky interface. These findings establish optimized O₂ plasma treatment as an effective post-etch recovery approach for mitigating dry-etch-induced damage and improving the interfacial uniformity and electrical reliability of β-Ga₂O₃ SBDs.

DOI：

https://doi.org/10.1016/j.mssp.2026.110994