Wet Oxidation of Semiconducting Silicon Carbide Wafers

Abstract

Abstract: Semiconducting silicon carbide (4H-SiC) exhibits characteristics of high hardness, notable brittleness, and excellent chemical stability. The commonly employed technique for achieving an ultra-smooth and flat surface is chemical mechanical polishing (CMP), which is utilized to process the 4H-SiC surface. Wet oxidation, as an important process of chemical-mechanical polishing of single-crystal 4H-SiC, directly affects the rate and surface quality of CMP. This paper provides a comprehensive overview of the current research status of wet oxidation of single-crystal 4H-SiC. It discusses the oxidants used in the wet oxidation of 4H-SiC, such as KMnO₄, H₂O₂, K₂S₂O₈. Based on this, it further summarizes commonly employed oxidation-enhancement methods, including photocatalytic-assisted oxidation, electrochemical oxidation, and Fenton reaction. The mechanism of wet oxidation of single-crystal 4H-SiC is analyzed from the aspect of theoretical calculation, and the future research direction of wet oxidation of 4H-SiC is proposed.

Key words: silicon carbide, semiconductor, processing, wet oxidation, chemical mechanical polishing, material remove rate

CLC Number:

TN305

LU Xuesong, WANG Wantang, WANG Rong, YANG Deren, PI Xiaodong. Wet Oxidation of Semiconducting Silicon Carbide Wafers[J]. Journal of Synthetic Crystals, 2024, 53(2): 181-193.

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