As-grown crystallized thin film of Bi-Sr-Ca-Cu-O and its low-temperature annealing effect

Abstract
The as‐grown crystallized films of low Tc phase (Tc∼80 K) in a Bi‐Sr‐Ca‐Cu‐O system were prepared by rf magnetron sputtering and were annealed in argon or oxygen atmosphere below 500 °C. Superconducting properties and the c‐axis lattice constant varied according to the annealing temperature and atmosphere. These results suggest that the oxygen content in the film is varied by low‐temperature annealing and that the variation of oxygen content affects the superconducting and structural properties. By cooling the sample in the chamber in 760 Torr oxygen, the as‐grown film with Tc end at 74 K was obtained.