SUPERCONDUCTIVE LAYER ON MONOCRYSTALLINE SUBSTRATE AND PROCESS FOR ITS PREPARATION

摘要

: A superconductive article is disclosed comprised of a substrate having a monocrystalline oxide surface supporting a superconductive crystalline oxide layer satisfying the formula: P2Sr2CanCUn+1O6+2n-z where P represents Bi1-zPbz; n is zero, 1 or 2; and z is 0 to 0.30. At least half of the crystal unit cells of the superconductive crystalline oxide layer are oriented with their c-axes normal to the substrate surface and with their minor axes relatively angularly aligned within a deviation range of less than 5.degree.. The superconductive crystalline oxide layer is formed by (a) applying to the substrate surface a coating solution comprised of a volatilizable film forming solvent and metal-ligand compounds of each of P, Sr, Ca and Cu containing at least one thermally volatilizable organic ligand, with at least one fluoro-substituted organic compound providing a F:Sr atomic ratio of at least 3:1, (b) removing the volatile components of the coating by heating and (c) forming the residual components of the coating into the superconductive crystalline oxide layer by firing to a temperature in the range of from 800 to 860.degree.C.