Low temperature epitaxial growth of Ge on CaF2 buffered cube-textured Ni

Quasi-single crystal Ge films were grown on cube textured Ni substrate at a temperature of 350 °C using an insulating buffer layer of CaF₂. A direct deposition of Ge on Ni at 350 °C was shown to alloy with Ni. From x-ray pole figure analysis, it was shown that Ge grew epitaxially with the same orientation as CaF₂ and the dispersions in the out-of-plane and in-plane directions were found to be 1.7±0.1° and 6±1°, respectively. In the out-of-plane direction, Ge111]6CaF₂111]6Ni001]. In addition, the Ge consisted of four equivalent in-plane oriented domains such that two mutually orthogonal directions: Ge〈2?11〉 and Ge〈01?1〉 are parallel to mutually orthogonal directions: Ni〈1?10〉 and Ni〈1?1?0〉, respectively, of the Ni(001) surface. This was shown to originate from the four equivalent in-plane oriented domains of CaF₂ created to minimize the mismatch strain between CaF₂ and Ni in those directions.