Low temperature phase formation of Tl-based superconducting thin films in reduced oxygen atmosphere

Authors

C.Y. Wu, University of Nebraska - Lincoln
F. Foong, University of Nebraska - Lincoln
Sy_Hwang Liou, University of Nebraska-LincolnFollow
J.C. Ho, University of Nebraska - Lincoln

Date of this Version

March 1993

Comments

IEEE Trans. on Appl. Superconductivity, 3, 1205(1993). Copyright 1993. Permission to use.

Abstract

Tl-Ba-Cu-Cu-O superconducting thin films were prepared by magnetron sputtering with postannealing in a reduced oxygen atmosphere. Single-phase Tl₂Ba₂Ca₂Cu₃O_χ can form on the MgO substrate at 800°C under P(O₂)≈0.1 atm. However, the phase formation temperature can be affected by the starting composition of the film. Tl₁Ba₂ Ca₂Cu₂O_χ phase can be formed by simply lowering the Tl2O pressure. The thermal stability of Tl₁Ba₂Ca₂Cu₃O_χ phase was studied by resistivity measurements at high temperatures.