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采用分子动力学方法模拟研究了未重构的金刚石 /硅 (0 0 1)面相接触时界面层原子的弛豫过程及所形成的异质界面的结构特征 .硅碳二元系统中原子间的相互作用采用Tersoff多体经验势描述 .弛豫前沿 [110 ]与 [110 ]方向界面碳硅原子数之比均为 3∶2 .界面碳硅原子总数之比为 9∶4.弛豫后金刚石与硅界面处晶格匹配方式改变为[110 ]方向基本上以 3∶2关系对准 ,而 [110 ]方向大致以 1∶1关系对准 .相应地 ,界面碳硅原子总数之比接近 3∶2 .界面下方部分第二层硅原子在弛豫过程中向上迁移至界面是引起这种变化的原因 ,同时该层其他原子及其底下一到两个原子层厚度的区域在 [0 0 1]方向上出现一定程度的无序化转变倾向 .金刚石 /硅异质界面处的硅碳原子发生强烈键合 ,形成平均键长为 0 189nm的硅碳键 .研究证实 ,晶格匹配主要呈现界面及其附近硅原子迎合界面碳原子排列的特点 .
Molecular dynamics simulation was used to study the relaxation process of the interface layer atoms and the structural characteristics of the formed heterogeneous interface when the undoped diamond / silicon (0 0 1) The interaction is described by the Tersoff multi-body empirical potential. The ratio of the number of carbon to silicon atoms in the [110] and [110] directions of the front of the relaxation is 3: 2, and the ratio of the total number of carbon to silicon atoms in the interface is 9 to 4. After relaxation, Alignment to the [110] orientation is essentially aligned in a 3: 2 relationship with the lattice matching approach at the Si interface, whereas the [110] orientation is approximately aligned in a 1: 1. Accordingly, the ratio of the total number of carbon to silicon atoms in the interface approaches 3 : 2. The reason why the second layer of silicon atoms in the lower part of the interface migrate upward to the interface during the relaxation process is that the other atoms in the layer and the thickness of one to two atomic layers in the bottom layer are in [0 0 1 ] Orientation, there is a certain degree of disordered transformation tendency.The silicon carbon atoms at the diamond / silicon hetero interface are strongly bonded to form silicon carbon bonds with an average bond length of 0 189nm.The study shows that the lattice matching mainly presents the interface And the nearby silicon atoms catered to interface carbon Sub-arranged features.