The effect of lattice strain on step edge diffusion

Abstract

The effects of lattice strain on the step edge diffusion of Ag(111) and Ag(100) surfaces are analyzed using molecular statics (MS) based on the semi-empirical embedded atom method (EAM) potential. The calculation of activation barriers of adatom diffusion on surfaces, diffusion over step edge, island corner diffusion, and diffusion along step under strained conditions shows that lattice strain greatly affects the energy barriers of various diffusion processes. For example, comparison shows that the Ehrlich-Schwoebel (ES) barrier decreases as lattice strain increases, which is opposite with strain dependency of surface diffusion barrier, and the diffusions along two different types of steps on Ag(111) surface have a lattice strain dependency different from each other. These different diffusion barrier behavior dependencies on lattice strain have interesting implications on the morphological evolution of strained thin film.