Thin film preparation of superconducting perovskite-type oxides by rf sputtering

Superconducting thin films of perovskite-type oxide of BaPb sub(1-x)Bi sub(x)O3 (x = 0.2, 0.25, 0.3, 0.4) and Basub(0.95)Srsub(0.05)Pbsub(0.75)Bisub(0.25)O3 were prepared by rf sputtering with their superconducting transition onsets of about 8 K. The films tended to lack Pb and Bi and this tendency could be reduced by sputtering under sufficiently high oxygen partial pressure. The transition temperature becomes reduced in both cases of low (x = 0.2) and high (x = 0.4) Bi content. The strontium substitution aiming at sharp transitions was not so effective as in the bulk materials and resulted in high resistive thin films. (author)