Effects of contactless photoelectrochemical reaction on repair of etching damage in GaN SBD

• Published in: Materials science in semiconductor processing Vol. 183; p. 108756
• Main Authors: Li, Xin, Liang, Zhiwen, Wang, Fengge, Xu, Yanyan, Liu, Zenghui, Liang, Yisheng, Lin, Lizhang, Zhang, Baijun
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.11.2024
• ISSN: 1369-8001
• DOI: 10.1016/j.mssp.2024.108756

This research investigates the reparative impact of photoelectrochemical (PEC) reactions on damage induced by inductively coupled plasma (ICP) etching in process of the Schottky barrier diodes (SBDs). After the PEC reaction repair, the reverse leakage current of the devices exhibited a significant reduction, typically ranging from 1 to 3 orders of magnitude. The ideality factor decreased from approximately 5 to 2, accompanied by a simultaneous decrease in series resistance. SBDs subjected to PEC processing displayed a notable decline in frequency dispersion. Quantitative analysis from capacitance-frequency measurements indicated that the PEC process effectively rectified the damage caused by dry etching on the GaN surface. The results of X-ray Photoelectron Spectroscopy (XPS) showed that the gallium oxide formed on a GaN surface by PEC treatment and the ratio of N/(Al + Ga) becomes larger, which indicates that fewer nitrogen vacancies (NV) after PEC repair process. The mechanism of the repair effects of PEC for the SBDs were discussed and analyzed. The observed improvements underscore the efficacy of PEC reactions in mitigating the adverse effects of etching, providing some inspirations for the enhancement of SBD performance in GaN-based devices.