EFFECTS OF LATTICE STEPS ON ATOM DYNAMICS, SURFACE-DIFFUSION AND EPITAXIAL-GROWTH

When an adatom encounters a lattice step, it can either be reflected o r not reflected regardless of whether the step is a 'descending or an ascending' step. These two types of steps are remarkably similar. In a ddition, lattice steps can act as atom-trap boundaries for diffusing a toms. Our FIM studies are briefly summarized. Based on our experimenta l data, we explain in simple terms that the 'high temperature' behavio r of surface atoms and growth structures in thin film epitaxy are dete rmined by the atom trapping property of the steps, whereas the 'low te mperature' behavior and growth structures are determined by the reflec tion property of the steps. (C) 1997 Elsevier Science B.V.