MBE Growth Mechanisms of ZnSe

Abstract

The effects of molecular beam flux and substrate temperature on the MBE growth rate of ZnSe are studied. It is found that, at relatively high substrate temperatures, the growth rate is influenced by the desorption and adsorption of Se and Zn atoms. The reduction of growth rate results from Se atom desorption, Zn atom desorption, and both Zn and Se atoms desorption at flux rations, J_Zn/J_Se>1, <1, and ≅1, respectively. The activation energy values are 1.2eV for the desorption of Zn atoms and 0.86eV for the desorption of Se atoms. Three MBE growth models were applied to explain the present results. A model considering the desorption of Zn and Se atoms from precursor states is proposed in this paper and it can best explain the relationship between the growth rate and the substrate temperature or the flux ratio.