CHEMICAL-VAPOR-DEPOSITION OF HIGH-T(C) SUPERCONDUCTING THIN-FILMS

Fabrication of high-temperature superconducting thin films (Y-Ba-Cu-O, Bi-Sr-Ca-Cu-O, Tl-Ba-Ca-Cu-O systems) by chemical vapour deposition ( CVD) is reviewed. The key to the use of the CVD method is to find vola tile compounds for the metallic constituents of superconductors. Beta- diketonate complexes such as acetylacetonates and dipivaloylmethanates have been successfully used as source materials. The quality of the f ilms grown is affected by the deposition temperature, substrate materi al and post-deposition annealing procedure. Considerable progress has recently been made and the critical properties of CVD-grown films are now equal to those of physical vapour-deposited films.