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We have investigated the fabrication of thin‐film superconductors by Cu‐ion implantation into initially Cu‐deficient Y(BaF2)Cu thin films. The precursor films were co‐evaporated on SrTiO3 substrates, and subsequently implanted to various doses with 400 keV 63Cu2+. Implantations were performed at both LN2 temperature, and at 380 °C. The films were post‐annealed in oxygen, and characterized as a function of dose by four‐point probe analysis, x‐ray diffraction, ion‐beam backscattering and channeling, and scanning electron microscopy. It was found that a significant improvement in film quality could be achieved by heating the films to 380 °C during the implantation. The best films made became fully superconducting at 60–70 K, and exhibited good metallic R vs T behavior in the normal state.

We have used nanoindentation to measure the mechanical properties of epitaxial TiN/(V0.6Nb0.4)N superlattices, grown on MgO(100), as a function of the wavelength λ. The V/Nb ratio within the VNbN layers was chosen to provide a lattice match with TiN, minimizing effects resulting from coherency strains. For λ≥4 nm, the hardness was found to be significantly enhanced relative to a homogeneous reference film of the same average composition. For λ