Ge Film Contacts to Radio Frequency Sputtered Y-Ba-Cu-O Superconductor Film

The semiconductor-superconductor con tact system of Ge/Y-Ba-Cu-O(YBCO)/ SrTiO₃ has been successfully fabricated by two steps of deposition. The YBCO film in the contact of Ge/YBCO did not lose its superconductivity and its T_c (on set) did not degrade as well. The top layer of Ge was polycrystalline with preferred orientation corresponding to the epitaxial structure of the underlayer of YBCO.