Structures and Superconducting Properties of Y-Ba-Cu-O Sputtered Films

Abstract
Y-Ba-Cu-O thin films were prepared by an RF magnetron sputtering technique. When annealed at temperatures between 920°C and 1000°C the crystal structures of these films are orthorhombic, while when annealed at 1010°C the structures are tetragonal. Superconductivity can be observed for the orthorhombic films. Their critical temperature (T c) of superconducting becomes higher as the a-axis becomes shorter, and is independent of the b-axis value.