Composite with Y-Ba-Cu-O superconductive film

This patent describes a composite consisting essentially of a crystalline superconductive film, a microscopically pore-free zirconium dioxide film and a substrate. The superconductive film having a composition represented by the formula YBaxCuyOz, where x ranges from about 1.9 to about 2.1, where y ranges from about 2.9 to about 3.1, and where z ranges from about 6.9 to about 7.0 The superconductive film having a zero resistance transition temperature of at least about 38 K and a thickness at least sufficient to be continuous ranging from about 0.4 micron to about 0.3 micron, the substrate being selected from the group consisting of monocrystalline elemental silicon, polycrystalline elemental silicon, oxidized monocrystalline element silicon, oxidized polycrystalline elemental silicon, amorphous silicon dioxide, monocrystalline aluminum oxide and polycrystalline aluminum oxide