Epitaxy and superlattice growth

Abstract

We have performed a rigid-lattice, atomistic, model calculation for bcc-fcc epitaxy. We have calculated the energy of an fcc (111) plane in contact with a bcc (110) substrate as a function of relative position, orientation, vertical displacement, and ratio of fcc/bcc lattice parameters. The results show two orientations for which deep minima exist in the dependence of energy on the fcc/bcc lattice parameter ratio. Our results are in qualitative agreement with earlier Moiré pattern studies. The calculations were made with two different atom-atom potentials; the results are found to be independent of the long-range attractive part of the potential. This implies that for rigid lattices the energetics is only determined by the relative atomic sizes of the substrate and overlayer. A comparison with experimental results indicates that the growth of metallic superlattices is controlled not only by epitaxial energetics but also by the stacking of the various constituents. DOI: http://dx.doi.org/10.1103/PhysRevB.30.6208 © 1984 The American Physical Society