The inter-surface migration of Ga adatoms between (001)-(2 x 4) and (111)B-(v19 x v19) or -(2 x 2) was investigated theoretically. Empirical interatomic potentials, and an energy term which was a function of the number of electrons which remained in the Ga dangling bonds, were used. The results indicated that the lattice sites on the (001)-(2 x 4)β2 surface were more favorable for Ga adatoms than those on the other surfaces. This was because the formation of Ga-Ga dimers in the missing-dimer rows on the (001)-(2 x 4)β2 surface decreased the number of electrons which remained in the Ga dangling bonds. The results suggested that Ga atoms were favorably adsorbed on the (001) top surface, and that Ga atoms which impinged on the (111)B side surface diffused to the (001) top surface provided that both the top and side surfaces were single-domain structures. The predictions were consistent with some aspects of experimental observations.

A theoretical investigation of the potential for the inter-surface migration of Ga adatoms between GaAs(001) and (111)B surfaces T.Ito, K.Shiraishi, H.Kageshima, Y.Y.Suzuki: Japanese Journal of Applied Physics - 2, 1998, 37[5A], L488-91