Surface stoichiometry determination using reflection high-energy electron diffraction and atomic-layer epitaxy: The case of ZnTe(100).

Abstract

Using reflection high-energy electron diffraction analysis of the relaxation process in highly strained heterostructures grown by atomic-layer epitaxy, a method is proposed to provide a quantitative determination of the surface stoichiometry. Applying this method to the case of the ZnTe(100) surface, we have found that a c(2\ifmmode\times\else\texttimes\fi{}2) Te-rich reconstruction observed below 240 \ifmmode^\circ\else\textdegree\fi{}C involves 1.5 ML of Te atoms. Consistent with this result, we also propose a microscopic model for the growth of ZnTe in atomic-layer epitaxy, and we demonstrate the relationship between growth rate and surface reconstruction.