Theoretical approach to influence of As2 pressure on GaAs growth kinetics

The newly developed first-principles calculation based computational method incorporating chemical potential of As2 gas is applied to understand the influence of As2 pressure on GaAs growth kinetics under the molecular beam epitaxy growth conditions with high As2 pressures where the c(4×4) reconstructed structure appears on the surface. The calculated results suggest that the chemical potential of As2 gas increases with As2 pressure, which suppresses As2 (As-dimer) desorption or extends As2 surface lifetime. This induces the decrease of GaAs growth rate, because GaAs layer-by-layer growth does not proceed without As2 desorption on the As-rich c(4×4) surface.