Zn-induced features at the GaAs(110) surface and its importance in the growth of ZnSe on GaAs(110)

A possible model for the ZnSe growth on GaAs(110) is proposed based on a first-principles pseudopotential method. Our calculations suggest that ZnSe growth on GaAs(110) could be understood in a two-step process: (i) Zn atoms will be adsorbed over Ga and As sites of the GaAs(110) surface, and (ii) the Zn atom over the Ga site will be replaced by a Se atom, followed by layer-by-layer ZnSe growth. We have also investigated Zn-induced features at the GaAs(110) surface, during the initial Zn interaction with the surface. Zn was found to adsorb preferentially at Ga substitutional sites at the subsurface layer and over Ga and As surface atoms. Theoretical STM images show the presence of bright features related to the Zn at Ga substitutional sites in the subsurface layers in agreement with recent experimental works. (C) 2002 American Institute of Physics.