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The critical parameters in the single-target magnetron sputtering of YBa2Cu3O7 have been identified and sufficiently optimized to allow the reproducible deposition of films with Tc’s of ≳90 K and Jc’s of ≫ 106 A/cm2 at 77 K. It was found that during film growth the bombardment of the YBa2Cu3O7 by energetic particles must be minimized and also a stronger oxidizing agent than molecular oxygen must be present to obtain films with these properties. Otherwise, films are deposited that, by x-ray diffraction and energy dispersive x-ray spectroscopy analyses, are indistinguishable from the highest-Tc 1:2:3 stoichiometric material but which have critical temperatures of ≪90 K. Films need not have 1:2:3 overall stoichiometry to have optimum superconducting properties. In such cases the excess elements are present as second-phase particles.

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Previous measurements of upper critical fields near Tc on NbN films with a small column (∼80 Å) void (∼10 Å) microstructure showed a strong anisotropy for applied fields perpendicular and parallel to the film surface. The perpendicular critical field was the larger one. Extrapolation of the perpendicular field data to zero temperature indicated an Hc2(⊥,0)>500 kG. Low temperature pulsed field measurements have now been made which show Hc2(⊥,0)=443 kG. In contrast, the measured upper critical fields of NbN films with equiaxed grains (≳275Å) or with larger columns (> 1000Å) and voids (∼500Å) indicate that these films behave like bulk superconductors. The Hc2(0)’s are ∼300 kG or less and little or no anisotropy is seen. A semiphenomenological theory incorporating size effects is used to interpret the data.

Undoped homoepitaxial and heteroepitaxial films of MBE grown InSb display n-type bulklike semiconducting properties, e.g., high mobility at 77 K. Epitaxial films with p-type conductivity were grown by in situ doping with Be. Transmission electron microscopy of cross-sectioned films showed that the large lattice mismatch between InSb and GaAs is accommodated by both dislocations and stacking faults. Phase separation at, and near, the surface of InSb–InBi deposits was shown by a combination of scanning electron microscopy, and energy dispersive x-ray analysis.