Atomic-scale three-dimensional kinetic Monte Carlo simulation of organometallic vapor-phase epitaxy of ordered films

Abstract

We present an atomistic three-dimensional method for simulating growth of ordered films during organometallic vapor-phase epitaxy (OMVPE). Epitaxial film evolution during growth is studied under typical OMVPE reactor conditions by using a kinetic Monte Carlo technique that incorporates important surface chemical reactions occurring in the reactor. The reactor model consists of a temperature-dependent deposition reaction and a surface etching reaction that depends on the local atomic environment. As a representative ordered film, we study the evolution of an AB film on a CsCl lattice. The growth of the epitaxial film is simulated on homoepitaxial, elemental, and disordered substrates with {011} and {001} orientations. Under typical OMVPE conditions, single-crystal homoepitaxial films are observed on homoepitaxial substrates. On elemental and disordered substrate, the film morphology showed domains of opposite orientations separated by antiphase boundaries. In all cases, the growth rate shows an Arrhenius dependence on temperature. Film quality as characterized by the short-range order decreases with increasing temperature. Surface roughness of the epitaxial films corresponds to a staggered surface consisting of a few (2--3) monolayers.