单个砷原子在砷化镓富砷表面的迁移行为

he potential energy surface for the migration of an extra As atom on the GaAs (001) β2 (2 × 4) surface was mapped out to study the diffusing behavior of the As atom by performing molecular dynamics calculations. Based on our calculations, some lower-energy sites and one possible pathway paralleling to the As dimers were found for the adsorption and diffusion of an extra As atom in this surface. According to the relative energies in the pathway, the energy barrier for the diffusing of the As atom was less than 0.6eV. Therefore it was inferred that the As atoms preferably kept their diffusion and formed clusters in the pathway at room temperatures.