A density-functional study was made of the mobility of cadmium and tellurium adsorbate atoms on the reconstructed Te-terminated (001) CdTe (2 x 1) surface. Two-dimensional potential energy surfaces as a function of the position of the adsorbate atom on the surface were calculated. For Cd as well as Te adsorption, two potential minima were found. The binding energies amount to -2. and -0.71eV for Cd (-2.8 and -1.4eV for Te). At any position of the surface, Te adsorption was found to be stronger than that of Cd. The results indicated that adsorption of a Te atom at the reconstructed Te-terminated (001) CdTe (2 x 1) surface led to adsorbates which could move along the surface due to their thermal energy. On the other hand, Cd adsorbate atoms were essentially trapped in the global minimum and desorption was expected to be much more likely than motion along the surface.

Density-Functional Study on the Migration of Cd and Te Adsorbates on the (001) Surface of CdTe. A.E.Patrakov, R.F.Fink, K.Fink, T.C.Schmidt, B.Engels: Physica Status Solidi B, 2010, 247[4], 937-44