Pulsed laser-induced liquid-phase epitaxial heterostructures which exposed both (100) and (111) orientations were studied by using non-equilibrium molecular dynamics simulations, with Stillinger-Weber potentials for the 2 components. The solid/liquid interface morphology, the quality of the re-grown materials, and the Ge distribution at the interface were studied under both fast and slow recrystallization conditions; as controlled by the substrate temperature. In the case of the (100) orientation, an appreciably non-planar solid/liquid interface was found for all Ge concentrations; with Ge atoms at the bottom of a so-called interfacial well causing solidification to be retarded in their vicinity. In the case of the (111) orientation, in-plane defects with alternating structures of two 5-membered rings and one 8-membered ring were found in the re-grown material; due to unstable growth kinetics on the so-called back side of the interface response function. At low crystallization rates, only stacking defects were found in the re-grown material; without in-plane defects. The Ge partition coefficient which was deduced from simulations of low re-growth rates was in good agreement with experimental data, and also agreed well with the predictions of a continuous growth model; if the Ge diffusivity at the solid/liquid interface and the width of the interface were used in calculating the so-called diffusive velocity.

Q.Yu, P.Clancy: Journal of Crystal Growth, 1995, 149[1-2], 45-58