高速旋转垂直热壁CVD外延生长n型4H-SiC膜的研究

摘要/Abstract

摘要： 采用高速旋转垂直热壁化学气相沉积(CVD)设备在偏向〈1010〉晶向 4°的 n 型4H-SiC衬底上进行了同质外延生长,在设定的工艺条件下,外延膜生长速率达到40.44 μm/h,厚度不均匀性和掺杂浓度不均匀性分别达到1.37%和2.79%。AFM表征结果显示表面均方根粗糙度为 0.11 nm;Leica显微镜观察显示外延膜表面光滑,生长缺陷密度很低,没有宏观台阶结构;Raman谱线清晰锐利,表现出典型的4H-SiC特征。综合分析表明,本实验使用国产的高速旋转垂直热壁CVD设备,在较高的外延生长速率下,获得了具有高厚度均匀性和高掺杂浓度均匀性的高质量4H-SiC外延膜,对目前碳化硅外延产业的发展和半导体设备的国产替代具有良好的指导作用。

关键词: 碳化硅, 外延, 化学气相沉积, CVD设备, 厚度均匀性, 掺杂浓度均匀性

Abstract: High-speed wafer rotation vertical hot-wall chemical vapor deposition (CVD) was employed to conduct home-epitaxial growth on n-type 〈1010〉 4° off-angel 4H-SiC wafer. With temperature of 1 650 ℃, pressure of 250 mbar and rotation rate of 600 r/min, growth rate of over 40.44 μm/h was achieved, epi-layer with thickness uniformity of 1.37% and doping concentration uniformity of 2.79% was obtained. AFM testing indicates that the surface roughness is 0.11 nm. Leica microscope indicates that the surface of epilayer is smooth and no macro-step existing, the sharp Raman lines show typical features of 4H-SiC, and defect density is very low. Comprehensive analysis shows that high-quality SiC epilayer is obtained with high growth rate by national high-speed wafer rotation vertical hot-wall CVD equipment. This research provides some guidance for current SiC epitaxial industry development and equipment localization.

Key words: SiC, epitaxy, chemical vapor deposition, CVD equipment, thickness uniformity, doping concentration uniformity

中图分类号:

韩跃斌, 蒲勇, 施建新, 闫鸿磊. 高速旋转垂直热壁CVD外延生长n型4H-SiC膜的研究[J]. 人工晶体学报, 2023, 52(5): 918-924.

HAN Yuebin, PU Yong, SHI Jianxin, YAN Honglei. Epitaxial Growth Study of n-Type 4H-SiC Films by High-Speed Wafer Rotation Vertical Hot-Wall CVD Equipment[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2023, 52(5): 918-924.

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