Growth of germanium crystal films on amorphous silicon by sputter deposition

Epitaxial Ge crystal and amorphous films grown on the amorphous Si buffer layers are reported. After optimizing growth condition, we obtained Ge crystal films by magnetron sputter deposition. The film crystallinity was characterized by Raman scattering and X-ray diffraction. We discuss the possible roles of the growth temperature and the amorphous Si buffer layer in promoting epitaxial growth of Ge films.