Compositional and Structural Analyses for Optimizing the Preparation Conditions of Superconducting (La_1-xSr_x)_yCuO_4-δ Films by Sputtering

Abstract

Reaction conditions and structural requirements for the preparation of superconducting films of (La 1- x Sr x ) y CuO 4-δ (LSCO) by sputtering have been elucidated. There are slight deviations in the film compositions from the target composition, especially when the substrate temperature was high. Optimum conditions for the preparation of superconducting films by 50 Hz ac sputtering include the sputtering in argon without intentional mixing of oxygen, the heating of substrate at moderate temperatures, and the annealing of the as-deposited films in oxygen atmosphere at temperatures between 500°C and 850°C.