As-grown superconducting Bi2Si2Ca2Cu3O<i>x</i> thin films with <i>T</i> <i>c</i>zero of 102 K prepared by rf magnetron sputtering

Abstract

As-grown high-quality superconducting thin films of the Bi2Sr2Ca2Cu3Ox were prepared by rf magnetron sputtering with a regulated shuttering technique. 2223 phase films with a 2201 phase buffer layer were deposited on MgO(100) substrates under rigorous control of the film composition, especially of bismuth contents. As a source of bismuth a sufficiently presputtered Bi2O3 target was used. At the preparation, Bi-Sr-Cu-O and Ca-Cu-O blocks were deposited alternately, no post-treatment steps were performed. The zero resistivity critical temperature of the as-grown film was 102.5 K and the critical current density at 4.2 K was 1.5×107 A/cm2. The growth rate was about 360 Å/h.