Preparation of TlCaBaCuO high- T sub c superconducting thin films on LaAlO sub 3 substrates (CN)

Pure 2122 phase and 2223 phase superconducting TlCaBaCuO thin films have been reproducibly prepared on (100)LaAlO{sub 3} substrates by dc magnetron sputtering using a pair of superconducting Tl{sub 2}Ca{sub 2}B{sub 2}Cu{sub 3}O{sub 10} targets and post-annealing at different temperatures. X-ray diffraction analysis indicates that the films are highly {ital c}-axis oriented perpendicular to the film surface for both types of the thin films. The critical transition temperature {ital T}{sub {ital c}}({ital R} = 0) = 98 K and critical current {ital J}{sub {ital c}}(77 K)=1.0{times}10{sup 5} A/cm{sup 2} can be obtained for 2122 phase films, and for 2223 phase films {ital T}{sub {ital c}}({ital R} = 0) = 115 K and {ital J}{sub {ital c}}(77 K) = 5.5 {times} 10{sup 5} A/cm{sup 2} can be obtained.