Reconstructed surfaces on (001) were investigated in situ, by means of reflection high-energy electron diffraction and core-level photo-electron spectroscopy, after heating a sample which had been prepared by depositing Sb onto an As-terminated (001) GaAs surface at room temperature. Before Sb desorption, the halo reflection high-energy electron diffraction pattern changed into 1 x 4, 1 x 3, and 2 x 4 between room temperature and 560C. This was contrasted with Sb/GaAs(110), which exhibited only a 1 x 1 pattern. It was found that a GaAs surface with a 2 x 4 pattern was terminated by a monolayer of Sb, and that these superstructure changes were caused by As atom desorption; followed by Sb atom substitution.

F.Maeda, Y.Watanabe, M.Oshima: Physical Review B, 1993, 48[19], 14733-6