摘要
在电容式耦合等离子体化学气相沉积系统中,使用高氢稀释硅烷为反应气体制备出了晶粒尺寸为2~10nm的纳米微晶相结构的硅薄膜,使用高分辨电子显微镜(HREM),X射线衍射谱(XRD),X射线光电子能谱(XPS)和红外光谱(IR)等结构分析手段检测了其结构特征.结果表明,纳米硅薄膜的晶格结构为畸变的金刚石结构.X射线衍射谱表明除了Si(111)的2θ=28.5°和Si(220)的2θ=47.3°处的衍射峰外,在2θ=32.5°处存在着一个强的异常峰.HREM结果表明存在新的Si结晶学结构与XRD异常峰相关联.研究结果还表明随着功率增加,Si薄膜网络结构的晶态成分增加.
Abstract Nanocrystalline silicon(nc-Si: H) films with an average grain size ranging from 2nm to 10nm were prepared by a plasma glow discharge CVD method. X-ray diffraction,High Resolution Electron Microscopy (HREM) were used to elucidate the structural nature in the nanocrystalline silicon films. The results show that the crystal lattice of the nanocrystalline silicon is a deformed diamond lattice. In the observed X-ray diffraction,there is an anomalous peak at 2θ=32. 5°of St besides the normal peaks at 2θ=28. 5°of Si(111) and 2θ=47. 3°of Si(220). The results of HREM show that a new crystallographic structure of silicon is found. The crystalline fraction of the network structure of silicon films increases with the increasing of RF power.EEACC: 0520, 2520F
关键词
纳米硅薄膜
结构特性
硅薄膜
Chemical vapor deposition
Crystal lattices
Crystal microstructure
Films
Nanostructured materials