Surface alloy formation of Co on Al surface: Molecular dynamics simulation

Abstract

Control of the interface structure of atomic scale multilayers is a fundamental issue to improve the performance of spin electronic devices. Deposition behavior of Co on Al surface at 300 K was investigated by molecular dynamics simulation. The deposited Co resulted in the formation of CoAl surface alloy regardless of the Al surface orientation. Structure of the surface alloy was dependent on the substrate orientation. Crystalline B2 structure was formed on Al (001) surface. On the contrary, amorphous mixed layers were evolved on Al (011) and (111) surfaces. In the case of Al (001) surface, 4 ML of the surface alloy were observed, which is consistent with the previous experimental observation. The present work shows that the formation of CoAl surface alloy should be considered even at the low substrate temperature and the low incident energy of deposited atoms.