Molecular Dynamics Study Of Low-Energy Silicon Fullerene Clusters Deposition On Silicon Surface

During the passed ten years, researching on semiconductor cluster especially C and Si cluster is a very hot topic. As Si and C are in the same group, people want to know whether Si₆₀ cluster has the similar structure of C60. Against this question, recently researching on the structure of Si₆₀ cluster and its electronic feature of basic state becomes hot topic in material science. Especially assembling nano-film by low energy beam of cluster deposition has become one of the hot topic in material science. The deposition of low energy cluster on surface is a complicated process. It is influenced by feature of substrate and deposited cluster, moreover it is related to the interactivity of atoms in the surface and interface and the competition between system thermodynamics and collision dynamics. So in improving the quality and preparing technique of film, it has important significance to study the interaction between fullerene and surface, to understand the process of film growth, and to explore the influence of nano-film by condition of experiment.First we describe the interaction among silicon atoms by Extended Brenner (XB) potential function based on molecular dynamics, introduce the basic concept and theory of molecular dynamics, and research the selection of potential function, algorithm of solving motion equations, boundary condition and initial condition. On the basis of that, we establish the simulation model of Si₆₀ deposition on silicon surface and composite simulating program.Second we consider the influences of projectile energy, entrance angle and position of impingement point, and study the simulation of single Si₆₀ deposited on Si(100) and Si(111) surface. Our research shows that towards Si(100) and Si(111) surface there are both suitable energy interval that are 10eV～50eV and 10eV～150eV. During that energy interval, Si₆₀ has high probability deposited on silicon substrate steadily, and keep the structure of fullerene cluster well. When it is smaller than that interval, there will be fewer bonds and this will do bad to deposition steadily; while, when it is larger than that interval, the structure of Si₆₀ will be broken.At last we analyze the angle effect to the oblique entrance deposition. It...