分子动力学模拟H原子与Si的表面相互作用

通过分子动力学模拟了入射能量对H原子与晶Si表面相互作用的影响. 通过模拟数据与实验数据的比较, 得到H原子吸附率随入射量的增加 呈先增加后趋于平衡的趋势. 沉积的H原子在Si表面形成一层氢化非晶硅薄膜, 刻蚀产物(H₂, SiH₂, SiH₃和SiH₄)对H原子吸附率趋于平衡有重要影响, 并且也决定了样品的表面粗糙度. 当入射能量为1 eV时, 样品表面粗糙度最小. 随着入射能量的增加, 氢化非晶硅薄膜中各成分(SiH, SiH₂, SiH₃)的量以及分布均有所变化. 关键词： 分子动力学 吸附率 表面粗糙度 氢化非晶硅薄膜

Molecular dynamics study of interaction between the H atoms and Si surface*

In this paper, molecular dynamics simulation is used to study the interactions between H atoms and the crystalline Si surface when H atoms bombard the Si surface in different incident energies. The results show that the adsorption rate of H atoms first increases and then reaches an equilibrium value with the increase of incident energy, which is consistent with the experimental results. The results also reveal that the H atoms are deposited on the Si surface, forming hydrogenated amorphous silicon film. The etching products (H₂, SiH₂, SiH₃ and SiH₄) influence the adsorption rate of H atoms, and determine the surface roughness of the hydrogenated amorphous silicon film. The surface roughness reaches a minimal value when the incident energy is 1 eV. However, both the yield and the distribution of the composition (SiH, SiH₂, SiH₃) in the hydrogenated amorphous silicon film change with the increase of incident energy.
Keywords： molecular dynamics adsorption rate hydrogenated amorphous silicon film roughness