Preparation of YBa₂Cu₃O_7-δ Thin Films by Metal-Organic Chemical Vapor Deposition Using Liquid Sources

Abstract

YBa 2 Cu 3 O 7-δ (YBCO) thin film was fabricated by metal-organic chemical vapor deposition (MOCVD) using newly developed liquid MO-sources (MO=metal-organic). The melting points of the MO-sources are lower than those of conventional MO-sources, and they have stable vapor pressure even in the liquid state. The MO-sources contain fluorine; however, when water was added to the flowing oxygen gas, the fluorine-to-oxygen ratio of the films was reduced to less than 0.08 at% as determined by secondary ion mass spectroscopy (SIMS). The reproducibility of the composition and the superconducting properties of the prepared films was excellent compared to that of films fabricated using conventional MO-sources.