Growth and equilibrium structures in the epitaxy of Si on Si(001)

Scanning-tunneling-microscopy measurements of submonolayer growth of Si on Si(001) show anisotropic island shapes. From coarsening experiments it is determined that these shapes are a consequence of the growth kinetics. They can be explained by a lateral accommodation coefficient for atoms arriving at the edge of islands that differs by an order of magnitude at the ends and at the sides of dimer rows. © 1989 The American Physical Society.