Atomic-Level Investigation for Surface Characteristics in a Co-Cu Multilayer System: Molecular Dynamics Simulation

Using molecular dynamics simulation, the growth behavior of Co atoms on Cu substrates for two different crystallographic orientations, (001) and (111), was extensively investigated. The surface roughness became noticeably higher during 20-monolayer (ML) deposition of Co thin-film on the Cu(111) substrate compared to the case of the Cu(001) substrate. It was found that the high diffusivity of Co adatoms on Cu(111) enhanced the atomic lateral movement, and the deposited Co adatoms could be agglomerated easily. The different growth behavior could be successfully explained in terms of the lateral atomic displacement and local acceleration energy.