半导体碳化硅衬底的湿法氧化

摘要/Abstract

摘要： 半导体碳化硅(4H-SiC)材料具有硬度高、脆性大、化学性质稳定等特点,一般使用化学机械抛光工艺来加工4H-SiC以获得超光滑平坦表面。湿法氧化作为单晶4H-SiC化学机械抛光的重要过程,直接影响着化学机械抛光的速率和表面质量。本文综述了目前单晶4H-SiC湿法氧化的研究现状,讨论了4H-SiC湿法氧化工艺所选用的氧化剂,如KMnO₄、H₂O₂、K₂S₂O₈等。在此基础上,进一步总结了常用的氧化增效方法,如光催化辅助氧化、电化学氧化、芬顿反应等,并从理论计算的角度分析了单晶4H-SiC湿法氧化的机理,最后展望了4H-SiC湿法氧化未来的研究方向。

关键词: 碳化硅, 半导体, 加工, 湿法氧化, 化学机械抛光, 材料去除率

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

中图分类号:

TN305

鲁雪松, 王万堂, 王蓉, 杨德仁, 皮孝东. 半导体碳化硅衬底的湿法氧化[J]. 人工晶体学报, 2024, 53(2): 181-193.

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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