Reaction kinetics for the CBE growth of GaAs from triethylgallium; computer modelling studies incorporating recent surface spectroscopic data

A new model for the decomposition of triethylgallium on GaAs(100), with kinetic parameters derived from the results of surface science experiments, is presented. Deficiencies of early models are corrected by including surface coverage and site blocking effects, and lateral interactions between absorbed DEG species are included. The model successfully predicts variations in the rate of CBE growth of GaAs with substrate temperature, and addresses effects induced by variations in arsenic overpressure. This dependence of growth rate on the arsenic flux is modelled by computing the steady state concentrations of absorbed arsenic as a function of temperature and As₂ and TEG flux. Excess arsenic is shown to inhibit GaAs growth by blocking sites for TEG absorption.