Effects of substrate temperature and Cu underlayer thickness on the formation of SmCo5(0001) epitaxial thin films

Abstract

SmCo 5 ( 0001 ) epitaxial thin films were prepared on Cu(111) underlayers heteroepitaxially grown on Al2O3(0001) single-crystal substrates by molecular beam epitaxy. The effects of substrate temperature and Cu underlayer thickness on the crystallographic properties of SmCo5(0001) epitaxial films were investigated. The Cu atoms of underlayer diffuse into the SmCo5 film and substitute the Co sites in SmCo5 structure forming an alloy compound of Sm(Co,Cu)5. The ordered phase formation is enhanced with increasing the substrate temperature and with increasing the Cu underlayer thickness. The Cu atom diffusion into the SmCo5 film is assisting the formation of Sm(Co,Cu)5 ordered phase.