YBCO THIN-FILM FORMATION NEAR THE STABILITY LINE BY RESISTIVE EVAPORATION OF BAF2, CU, AND Y

A single resistively heated source was used to deposit a mixture of Ba F2, Cu, and Y to form precursor films onto MgO substrates held at room temperature, Different heat treatment conditions were applied to stud y the stability diagram of YBa2Cu3O7-x. It was found that the stabilit y line is shifted toward the higher oxygen partial pressure and lower temperature side of the pure YBCO line in the presence of fluorine and fluorides in the precursor Films of good quality were obtained when t he annealing conditions were in close proximity to this line.