Author(s): Wang, Q (Wang, Qi); Zhou, KH (Zhou, Kehong); Zhao, S (Zhao, Shuai); Yang, W (Yang, Wen); Zhang, HS (Zhang, Hongsheng); Yan, WS (Yan, Wensheng); Huang, Y (Huang, Yi); Yuan, GD (Yuan, Guodong)

Source: NANOMATERIALS Volume: 11 Issue: 12 Article Number: 3179 DOI: 10.3390/nano11123179 Published: DEC 2021

Abstract: Realizing the anisotropic deep trenching of GaN without surface damage is essential for the fabrication of GaN-based devices. However, traditional dry etching technologies introduce irreversible damage to GaN and degrade the performance of the device. In this paper, we demonstrate a damage-free, rapid metal-assisted chemical etching (MacEtch) method and perform an anisotropic, deep trenching of a GaN array. Regular GaN microarrays are fabricated based on the proposed method, in which CuSO4 and HF are adopted as etchants while ultraviolet light and Ni/Ag mask are applied to catalyze the etching process of GaN, reaching an etching rate of 100 nm/min. We comprehensively explore the etching mechanism by adopting three different patterns, comparing a Ni/Ag mask with a SiN mask, and adjusting the etchant proportion. Under the catalytic role of Ni/Ag, the GaN etching rate nearby the metal mask is much faster than that of other parts, which contributes to the formation of deep trenches. Furthermore, an optimized etchant is studied to restrain the disorder accumulation of excessive Cu particles and guarantee a continuous etching result. Notably, our work presents a novel low-cost MacEtch method to achieve GaN deep etching at room temperature, which may promote the evolution of GaN-based device fabrication.

Accession Number: WOS:000736528000001

PubMed ID: 34947528

Author Identifiers:

Author Web of Science ResearcherID ORCID Number

Zhao, Shuai 0000-0001-7171-2943

eISSN: 2079-4991

Full Text: https://www.mdpi.com/2079-4991/11/12/3179