TIGHT-BINDING RECURSION CALCULATIONS OF STEP ENERGETICS ON THE GAAS(110) SURFACE

On the GaAs(110) surface steps perpendicular to the [001] direction ma y be either arsenic-terminated or gallium-terminated. We, compute the energy difference between these steps using a tight-binding recursion method. We find that the arsenic-terminated step is more stable by app roximately 0.5 eV. Our results suggest that some recent experimental o bservations on the shape of islands formed during homoepitaxy on CaAs( 110) may be the consequence of an energy-driven rather than a kinetics -driven epitaxial growth. (C) 1997 American Institute of Physics.