Dynamical Calculations of RHEED Intensity Evolution During MBE Growth

Abstract

Reflection high energy electron diffraction (RHEED) has become well established as one of the most powerful and versatile techniques for growth and surface studies of semiconductor films prepared by molecular beam epitaxy (MBE). In particular the technique of RHEED intensity oscillations has been used routinely to calibrate beam fluxes and alloys composition and to control the thicknesses of quantum wells and superlattice layers.Although several interpretations have been proposed for the strong oscillations in RHEED intensity during MBE growth, full dynamical calculations have been done only for an artificial surface consisting of a periodic array of surface steps. The enormous amount of computation involved prevents the dynamical theory being applied to a more realistic epitaxically growing system. In this paper we report a simple and practical method for calculating dynamical RHEED from MBE growing surfaces.We first consider epitaxial growth on a low-index surface. The growth is simulated by using a perfect layer growth model and a diffusive growth model.