Microscopic model of heteroepitaxy of GaAs on Si(100)

A new microscopic model of heteroepitaxial growth is introduced using GaAs on Si(100) as a prototype. This model takes into account specific features of surface topology, predicts that in the prototype system conventional two-dimensional epitaxy should be inhibited, and provides a fundamental explanation for three-dimensional nature of the initial stages of growth. The ingredients of the model, which are supported by total-energy calculations, include new structural geometries for each state of growth and the chemical and rehybridization reactions linking these stages.