XPS studies on passivated and degraded YBa2Cu3O7−x films

✍ Scribed by Debasis Majumdar; Dilip Chatterjee; Gustavo Pav-Pujalt

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 357 KB
• Volume: 158
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(89)90237-2

✦ Synopsis

High-temperature YBa2Cu3OT_x superconductors are known to degrade in the presence of moisture. It was shown that the use of certain polymeric materials in solution during processing of the superconductor could passivate the film and reduce degradation in the macroscopic scale. X-ray photoelectron spectroscopy was used to study the surfaces ofpassivated as well as degraded YBa2Cu3OT_ x samples. In the degraded sample, Y, Ba, Cu and O were present in chemical states other than those expected in superconductors. Segregation of Ba at the surface was also observed. In the passivated sample, superconducting species were retained at the surface despite limited impurity build-up.