SINGLE TARGET SPUTTERING OF AS-GROWN SUPERCONDUCTING BI(-PB)-SR-CA-CU-O THIN-FILMS ON MGO(100)

As-grown superconducting thin films of Bi(-Pb)-Sr-Ca-Cu-O have been prepared on MgO (100) at 620–720°C by dc magnetron sputtering using a single target. The targets used were Pb-free Bi3Sr2Ca2.2Cu3Ox and Pb-doped Bi3Pb2Sr2Ca2.2Cu3Ox in nominal compositions. The as-grown process with no annealing yields c-axis oriented superconducting thin films with zero resistivity above 70 K. The superconducting properties of the thin films were affected by the substrate temperatures during film growth. The c-axis lattice constant of the films was also controlled to the value of 24–37 Å by changing the substrate temperature. The best film showed zero resistivity at 76 K and a superconducting 37 Å phase. The critical current density was measured at 4.2 K with Jc=2×106 A/cm2. © 1990 The Japan Society of Applied Physics.