Effects of hydrogen in Ni(100) submonolayer homoepitaxy

Abstract

The effects of hydrogen in Ni(100) submonolayer homoepitaxy have been investigated by classical-potential total-energy calculations with semiclassical hydrogen zero-point-energy corrections. The fast diffusion of H on a flat Ni(100) surface is found to persist even when the surface is decorated with various intrinsic defects such as Ni adatoms, islands, and steps created during epitaxial growth. On the other hand, the presence of H significantly enhances the mobility of both Ni adatoms and Ni islands, resulting in a decrease in the Ni island density and a corresponding increase in the average island size. These results suggest that hydrogen will function as an antisurfactant in Ni(100) homoepitaxy. Connections to available experiments are made. {copyright} {ital 1997} {ital The American Physical Society}