Formation of superconducting Bi-Sr-Ca-Cu-O thin films with controlled c-axis lattice spacings by multitarget sputtering

Thin films of the Bi-Sr-Ca-Cu-O system were prepared by sequential deposition of Bi, SrCu, CaCu and SrCu oxides using multitarget sputtering. It was confirmed that the c -axis spacing of lattice planes could be controlled by the variation of the CaCu oxide layer. Also, thin films of the Bi system with the insertion of four Cu-O 2 planes were synthesized. The T c s of the films were found to be 80 K, 110 K and 90 K for the Bi system with two, three and four Cu-O 2 planes, respectively.