JP2765138B

PURPOSE:To obtain a high-quality oxide superconducting thin film having excellent superconducting characteristics by irradiating an evaporation source comprising a compound oxide prepared by melting a raw material with laser beam, vaporizing and forming thin film on a substrate. CONSTITUTION:First, powder of raw material compound containing elements to constitute a thin film of oxide superconductor to be prepared is blended. For example, in the case of producing Y1Ba2Cu3O7-x oxide superconducting thin film, powder of Y2O3, BaO and CaO is blended so as to make an atomic ratio of Y:Ba:Cu of 1:2:3. Then, the blended powder is heated preferably to 1,100-1,600 deg.C, made into a completely molten state, maintained for 2-4 hours and then quenched. Then, the compound oxide prepared by quenching and solidification is heat-treated in an O2 atmosphere at 800-900 deg.C, namely annealed. Then the prepared evaporation source is irradiated with laser beam by a well- known method and vaporized to give a high quality oxide superconducting film on a substrate.