High anisotropy on epitaxial C-doped Mn5Ge3 thin films grown on Ge(001)

Epitaxial Mn5Ge3C0.6 thin films were grown on Ge(001) substrates by magnetron sputtering utilizing the reactive deposition epitaxy method at 623 K. The c-axis of the hexagonal crystalline structure of Mn5Ge3 lies in the film plane with the epitaxial relationship Ge(001)[110]∥Mn5Ge3(012)[011]. The film exhibits a large in-plane magnetic anisotropy ten times larger than that observed on Mn5Ge3C0.6 thin films grown on Ge(111) substrates attributed to the double contribution of magnetocrystalline and shape anisotropies. The magnetization M-H curves indicate that the easy magnetization axes lie in the film plane independent of the selected azimuthal, while the normal to the film plane is a hard axis. The films exhibit a ferromagnetic behavior with a Curie temperature of 425 K. Epitaxial Ge(001)/Mn5Ge3C0.6 is therefore proposed as a promising functional material for spintronic applications, which could be directly integrated into the Si technology.