Molecular-dynamics simulation of the growth of strained-layer lattices

Simulation of strained-layer growth of two-dimensional Lennard-Jones crystal lattices has been performed using molecular dynamics. In particular, we have studied the influences of lattice mismatch and substrate temperature on the growth, from the vapor phase, of overlayer material possessing a different bulk lattice constant than that of the substrate material. Simulation results predict that at substrate temperatures less than 50% of melting, epitaxial growth occurs for mismatch values less than 4%, whereas above this value, defective growth is observed. At temperatures above 50% of the melt temperature, mass transport occurs across the layer interface and rapid diffusion is observed in the topmost atomic layers, resulting in liquidlike behavior in a thin layer over ordered crystal.