Monte Carlo simulation of the effect of interstitial atoms interaction on the heteroepitaxial growth of compound semiconductors

We have investigated the kinetics of heteroepitaxial growth with large lattice mismatch by associating the Monte Carlo technique with an energy model based on valence force field (VFF) approximation. The energy model allows the acceleration of the atomic motions as a function of local strain energy and a relaxation of most stressed positions. We have observed the roughening of the surface followed by the formation of (111) facets, the apparition of highly mobile atoms in interstitial positions on these facets and the reaction between these atoms. The reactions are seen to lead to stabilized nuclei with dangling bonds which are at the origin of point defects or extended defects in the growing layer.