Issue 12, 2018, Issue in Progress

Effect of OH on chemical mechanical polishing of β-Ga2O3 (100) substrate using an alkaline slurry

Abstract

β-Ga2O3, a semiconductor material, has attracted considerable attention given its potential applications in high-power devices, such as high-performance field-effect transistors. For decades, β-Ga2O3 has been processed through chemical mechanical polishing (CMP). Nevertheless, the understanding of the effect of OH on β-Ga2O3 processed through CMP with an alkaline slurry remains limited. In this study, β-Ga2O3 substrates were successively subjected to mechanical polishing (MP), CMP and etching. Then, to investigate the changes that occurred on the surfaces of the samples, samples were characterised through atomic force microscopy (AFM), three-dimensional laser scanning confocal microscopy (LSCM), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). LSCM and SEM results showed that β-Ga2O3 is highly vulnerable to brittle fracture during MP. AFM revealed that an ultrasmooth and nondamaged surface with a low Ra of approximately 0.18 nm could be obtained through CMP. XPS results indicated that a metamorphic layer, which mainly contains soluble gallium salt (Ga(OH)4), formed on the β-Ga2O3 surface through a chemical reaction. A dendritic pattern appeared on the surface of β-Ga2O3 after chemical etching. This phenomenon indicated that the chemical reaction on the β-Ga2O3 surface occurred in a nonuniform and selective manner. The results of this study will aid the optimization of slurry preparation and CMP.

Graphical abstract: Effect of OH− on chemical mechanical polishing of β-Ga2O3 (100) substrate using an alkaline slurry

Article information

Article type
Paper
Submitted
19 Oct 2017
Accepted
04 Feb 2018
First published
08 Feb 2018
This article is Open Access
Creative Commons BY license

RSC Adv., 2018,8, 6544-6550

Effect of OH on chemical mechanical polishing of β-Ga2O3 (100) substrate using an alkaline slurry

C. Huang, W. Mu, H. Zhou, Y. Zhu, X. Xu, Z. Jia, L. Zheng and X. Tao, RSC Adv., 2018, 8, 6544 DOI: 10.1039/C7RA11570A

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements