Monte Carlo Simulation of Thin Film Growth with Lattice Defects

Abstract

The structure of thin film deposited on a metal surface and formation of defects during the growth of the film have been studied with use of a kinetic Monte Carlo method. Simulations have been performed for a two-dimensional square lattice as a model of the growth from solution taking into account three events; adsorption, desorption and diffusion of surface atoms. The growth rate is controlled by the chemical potential µ which corresponds to the overpotential in electrodeposition. The solid-on-solid criterion, which is commonly used in modeling crystal growth, is not assumed in the present study. This extends to make lattice defects (vacancies) created in the film. It is shown that point defects (single vacancies) appear in the film when the surface has a layer structure for small µ and the density of defects increases as µ becomes large. For sufficiently large µ, the surface becomes rough and large voids are formed as well as point defects. The spatial distribution of defects in the film is closely rela...