Anisotropic spread of surface dimer openings in the initial stages of the epitaxial growth of Si on Si{100}

The initial stages of the epitaxial growth on the dimer-reconstructed Si{100} surface is modeled via molecular-dynamics simulations using the Tersoff many-body potential. We report a novel anisotropic spread of surface dimer openings in the direction perpendicular to the original dimer rows. This correlated reaction mechanism dramatically increases the crystal-growth process in one direction as confirmed by recent scanning-tunneling-microscope studies.