The Simulation Of Three Dimensional Thin Film Growth On Fcc(111) Surface

With the development of science and technology, the thin film manufacture technology is playing a very important role nowadays. The speed of film achievements in scientific research into productive forces is faster. Because of the complicated growing process of thin film, there are some difficulties to study thin film growth with experimental methods. The microstructure evolution of thin film has been studied in dimension of atom cluster by computer simulation technique. It is important to improve and optimize the deposition process, film quality and properties with the computer simulation process.In this paper, a three dimensional thin film growth model based on the Kinetic Monte Carlo method was proposed, the simulation substrate is900x900hexangular lattices with the periodic boundary conditions. Processes of motion about particles’deposition from high level to low level, diffusion on the substrate, interlayer diffusion, nucleation and islands growth were considered in this model. Then we analyzed the growth morphology of substrate of face center cubic lattice (111)(triangular island, hexagonal island) under different growth conditions. At the same time, simulation results and the experimental results were compared, the simulation results matched well with the experimental results. On the base of the above research, the characters of thin film growth in the fixed deposition-bit model were simulated under different growth conditions, such as substrate temperature, deposition rate, coverage, etc. The defects of several situations such as stacking fault and normal growth situation were compared. The random deposition of atoms in the fcc, hcp-bit model was considered, and the two models in different growth conditions were compared.According to the simulation, we discussed that:the bondage ability of the nearest atoms is the main factor of forming island morphology; the process of particles’moving around the island makes the island morphology tend to be compact, and forms a large number of threefold hollow sites, the process also increases the growth probability of the upper particles and the surface roughness of thin film; the diffusion anisotropy of atoms is a main determinant of morphology from hexagonal island to triangle island; there is little different between the island morphology of stacking fault and the normal morphology of the island; in the same condition, the number of islands in atomic fcc, hcp-bit random deposition model is more than that in the fixed deposition-bit model, the average size of island in atomic fcc, hcp-bit random deposition model is smaller, and the roughness of thin film in the random model is lower; the roughness of the thin film ascended with the increasing of the coverage and ascending probability and descended with the increasing of descending probability, with the substrate temperature and deposition rate increasing, the roughness ascended at first and then descended.