Effects of tensile strain on Ag(111) epitaxial growth by kinetic Monte Carlo simulations.

The effects of surface strain on epitaxial growth are studied using the kinetic Monte Carlo (KMC) method. The strain dependences of the activation energy barrier and the attempt frequency of each elementary process are evaluated by the embedded atom method interatomic potential. KMC simulations of homoepitaxial growth on a Ag(111) surface with equibiaxial tensile strain are carried out and influences of the surface strain on the nucleation of islands and the surface morphology are investigated. The island density increases due to reduction of the adatom diffusion on the terrace. The averaged coordination number of atoms constituting islands decreases and the island shape is more dendritic. The tensile surface strain leads to an increase in the surface roughness at an early stage of the growth, but at high coverage the roughness is adversely lower for the strained surface.