The simulation of single-crystal growth by molecular beam epitaxy using a kinetic rate-equation model

Abstract

A computer simulation of Molecular Beam Epitaxial (MBE) growth under typical growth conditions is presented. The method is based on a solution of kinetic rate equations that govern the time dependence of the concentration of islands of varying sizes and differing heights on the top of the surface during the MBE growth. The time dependence for the coverage of each monolayer (θ) is calculated. The mode of the MBE growth is determined by a calculation of the RHEED (Reflection High-Energy Electron Diffraction) intensity. A calculation of the Exposed Coverage (EC) (which is defined as the number of surface atoms in each layer unscreened by other atoms directly above them) and the interface width (IW) (which determines the roughness of the growing surface) serves to confirm the growth mode of the MBE structure. The possible role of these type of calculations in determining the optimized growth conditions for the production of 2D growth in a general materials system is also described.