半导体碳化硅湿法腐蚀工艺研究

摘要/Abstract

摘要： 碳化硅(SiC)具有禁带宽度大、电子饱和漂移速度高、击穿场强高、热导率高、化学稳定性好等优异特性,是制备高性能功率器件等半导体器件的理想材料。得益于工艺简单、操作便捷、设备要求低等优点,湿法腐蚀已作为晶体缺陷分析、表面改性的常规工艺手段,应用到了SiC晶体生长和加工中的质量检测以及SiC器件制造。根据腐蚀机制不同,湿法腐蚀可以分为电化学腐蚀和化学腐蚀。本文综述了不同湿法腐蚀工艺的腐蚀机理、腐蚀装置和应用领域,并展望了SiC湿法腐蚀工艺的发展前景。

关键词: 碳化硅, 湿法腐蚀, 电化学腐蚀, 化学腐蚀, 晶体缺陷, 晶体表面

Abstract: Silicon carbide (SiC) possesses excellent properties of wide band gap, high electron saturation velocity, high breakdown field strength, high thermal conductivity and good chemical stability, etc. SiC is an ideal raw material for high-performance power device and other semiconductor devices. With the advantages of simple processing, convenient operation and low-cost equipment requirements, wet etching has been adopted in the materials characterization and device of SiC. Defect analysis and surface modification can all greatly benefit from wet etching. According to the underlying mechanisms, wet etching can be classified into electrochemical etching and chemical etching. In this review, the mechanisms, equipments and applications of both electrochemical etching and chemical etching have been introduced.

Key words: silicon carbide, wet etching, electrochemical etching, chemical etching, crystal defect, crystal surface

中图分类号:

TN304

张序清, 罗昊, 李佳君, 王蓉, 杨德仁, 皮孝东. 半导体碳化硅湿法腐蚀工艺研究[J]. 人工晶体学报, 2022, 51(2): 333-343.

ZHANG Xuqing, LUO Hao, LI Jiajun, WANG Rong, YANG Deren, PI Xiaodong. Research Progress on Wet Etching of Semiconductor SiC[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2022, 51(2): 333-343.

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