The atomic structures of Ga and As atoms on (110) planes were studied by using a first-principles pseudopotential method. It was found that both Ga and As atoms resided in the center of a triangle that consisted of a surface Ga atom and 2 surface As atoms in the single-atom chemisorbed state. The adsorption energies for Ga and As atoms were 3.1 and 3.5eV, respectively. The energy barrier heights for Ga and As atoms which migrated along the path through the interstitial channel were found to be 0.6 and 1.0eV, respectively. Simulation of the deposition of 2 atoms revealed that pair formation was stable with respect to separate single-atom chemisorption.

J.Y.Yi, J.Y.Koo, S.Lee, J.S.Ha, E.Lee: Physical Review B, 1995, 52[15], 10733-6