用SiCl_4-H_2低温沉积多晶硅薄膜微结构的Raman分析

Raman analysis of microstructure of polycrystalline silicon films deposited at low-temperatures from SiCl_4-H_2

用拉曼散射谱研究以SiCl4 H2 为气源 ,用射频辉光放电等离子体增强化学气相沉积技术 ,在 2 0 0℃低温下沉积多晶硅薄膜的微结构特征 .结果表明 ,薄膜表层包含有大量微晶相的纳米硅晶粒和非晶相的硅聚合物 ,随射频功率增加 ,晶相结构的成分增大 .另一方面 ,深度拉曼谱分布的研究也显示薄膜的晶化度和晶粒尺度随纵向深度的增加逐渐增大 .因此可以认为 ,在多晶硅薄膜生长的最初阶段 ,空间反应过程对低温晶化起重要作用 .

The microstructure of polycrystalline silicon films prepared at 200℃ by radio frequency(RF) glow discharge plasma-enhanced chemical vapor deposition technique from SiCl 4/H 2 has been investigated by Raman scattering. The results show that the growing surface of the films contains a large amount of silicon nano-crystalline grains and the clustered silicon of amorphous phase. The component of crystalline phase increases with the increase in RF power. On the other hand, the investigation on the depth profiles Raman spectra indicates that the crystallinity and the grain size increase with increasing depth from the film surface. It is considered that in the initial stage of film growth, the space reaction processes play an important role for the low-temperature crystallization of pc-Si film.