Modelling of compound semiconductor epitaxy

In this work, a two step approach to model compound semiconductor epitaxy i s presented. As first step, a Monte Carlo (MC) simulation of GaAs growth is developed, which may be understood as "numerical experiment". To ensure th e greatest possible agreement between MC simulations and real growth, all s imulation parameters are determined unequivocally by comparison with experi mental data taken during molecular beam epitaxy. On the other hand, a set o f coupled rate equations for the densities of mobile species and of growth islands is fomulated, which accounts for surface diffusion of Ga and As ato ms as well as of GaAs molecules. With our self-consistent rate theory, we c alculate average values of the densities of two-dimensional growth islands, mobile Ga atoms and GaAs molecules and compare these to MC simulation resu lts. We find very good agreement indicating that the rate equations describ e well the atomistic processes during growth. (C) 1999 Elsevier Science B.V . All rights reserved.