Method of fabricating thin film superconducting materials

Improved superconducting thin films are provided having very high Tc (zero) and Jc values, on the order of greater than or equal to 120K and 105 A/cm2 or greater, respectively. The films of the invention are adapted for deposit and support on a compatible substrate, and include a superconductive material, most preferably Tl2Ba2Ca2Cu3O10, with up to about 10% elemental gold admixed with the superconductive material. The preferred method for fabricating the thin film superconductors comprises first forming a non-superconducting precursor film on a compatible substrate which is placed in contact with an unsintered bulk body containing thallium; the substrate with precursor film are sintered with the bulk body to form the desired superconductor material.