Oriented high-temperature superconducting Bi-Sr-Ca-Cu-O thin films prepared by ion beam deposition

Abstract
High‐temperature superconducting Bi‐Sr‐Ca‐Cu‐O thin films have been prepared by ion beamsputter deposition.Films near the 2:2:1:2 and 4:3:3:4 compositions were deposited onto single‐crystal MgO [100] substrates and annealed between 825 and 880 °C. Films with composition Bi2.00Sr2.09Ca0.75Cu2.44O x have a transition beginning at approximately 85 K, with T c (R=0) reached at 75 K. For films with composition Bi4.00Sr3.12Ca3.03Cu4.56O x , a significant drop in the resistance is observed at about 110 K, with T c (R=0) between 63 and 67 K. Films of both compositions have strong preferential c‐axis orientation normal to the film plane.