Epitaxial growth of Co2MnSi thin films at the vicinal surface of n-Ge(111) substrate

The structure and magnetic properties of Co2MnSi films on n-Ge(111) substrate were investigated for the motivation of spin injection. The 50-nm-thick Co2MnSi films were fabricated on n-Ge(111) substrates by dc sputtering and postannealed about 1 h at the various temperatures ranging from 200-500 deg. C. In the annealing temperature range of 300-400 deg. C, the Co2MnSi were grown epitaxially at the vicinal surface of n-Ge(111) substrates. The epitaxial layer of Co2MnSi films was about 18 nm thick at 350 deg. C and exhibited ferromagnetic behavior. Interestingly, there was no diffusion of Ge inside the epitaxial layer and atomically flat interface was obtained.