Low temperature epitaxial growth of Ge on cube-­‐textured Ni

Abstract

Quasi-­‐single crystal Ge films were grown on [001] textured Ni substrate at a temperature of 350 oC using an insulating buffer layer of CaF2. A direct deposition of Ge on Ni at 350 oC 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±0.1o and 6±1o, respectively. In the out-­‐of-­‐plane direction, Ge[111]||CaF2[111]||Ni[001]. In addition, the Ge consisted of four equivalent in-­‐ plane oriented domains such that two mutually orthogonal directions: Ge 211 and Ge 011 are parallel to mutually orthogonal directions: Ni 110 and Ni 110 , respectively of the Ni(001) surface. This was shown to be originated from the four equivalent in-­‐plane oriented domains of CaF2 created to minimize the mismatch strain between CaF2 and Ni in those directions.