Sputtered films

New metallurgical phases and enhanced superconductivity can be obtained using hot substrate sputtering. Some advantages and limitations of this technique are discussed. For Nb-Ge studies of Tc, resistivity, crystallographic structure, compositional dependences, and impurities are summarized. Although Tcvaries with composition it is not found to be critically dependent upon exact stoichiometry and, at the same composition, is considerably higher in the films than in the bulk. A simple correlation between Tcand resistance ratio is reported.