Simulation was used to estimate diffusion coefficients and mechanisms by means of a constant pressure and temperature algorithm. It was found that there was little diffusion of a vacancy in the solid GaAs; even near to the melting point. The diffusion coefficient of an interstitial arsenic atom was larger than that of an interstitial gallium atom. After formation of a dumb-bell pair in the [110] direction, an interstitial arsenic atom migrated in the [110] direction, while an interstitial gallium atom migrated in either the [110] or [¯110] direction. An interstitial arsenic atom pushed out a substitutional arsenic atom and then diffused via an interstitial mechanism, while an interstitial gallium atom pushed out a substitutional arsenic or gallium atom. All of the migrating interstitial atoms in solid GaAs switched to interstitial arsenic atoms in the final stage of diffusion.

Molecular Dynamics Analysis of Diffusion of Point Defects in GaAs. Kitashima, T., Kakimoto, K., Ozoe, H.: Journal of the Electrochemical Society, 2003, 150[3], G198-202