As-grown superconducting Bi(-Pb)-Sr-Ca-Cu-O films by electron cyclotron resonance plasma sputtering

Abstract

Bi(-Pb)-Sr-Ca-Cu-O thin films were prepared on MgO(100) single-crystal substrates by electron cyclotron resonance (ECR) plasma sputtering at substrate temperatures from room temperature to 590 °C. Pb-doped superconducting as-grown films were obtained above 560 °C. The Tc values of the Pb-doped films prepared at 570–590 °C were 58–64 K which increased with increasing substrate temperature. Pb-undoped as-grown films obtained at 590 °C showed superconduction (Tc =30 K), but the films obtained below 580 °C were semiconductors. The grain sizes and contents of the 37 Å phase (110 K phase) were increased by the Pb doping into the as-grown Bi-Sr-Ca-Cu-O films.