Tight-binding recursion calculations of step energetics on the GaAs(110) surface

Abstract

On the GaAs(110) surface steps perpendicular to the [001] direction may 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 approximately 0.5 eV. Our results suggest that some recent experimental observations on the shape of islands formed during homoepitaxy on GaAs(110) may be the consequence of an energy-driven rather than a kinetics-driven epitaxial growth.