Growth of YBa2Cu3O7-δ superconducting films under different atmospheres by pulsed laser deposition

Abstract

This paper aims to explore the epitaxial growth process for high-temperature superconducting YBa2Cu3O7-δ (YBCO) thin films by pulsed laser deposition (PLD) under different deposition atmospheres. The possibility of depositing YBCO superconducting thin films, under an oxygen-free environment, that was different from the oxygen atmosphere for most deposition processes of YBCO superconducting thin films was studied. Three different atmospheres, with oxygen, nitrous oxide, and nitrogen, were used in the experiment. The influence of atmospheric pressure on the formation and superconductivity of the YBCO phase were studied in detail. The characterization of structure and electrical properties of the thin films showed that YBCO thin films showed highly preferentially growth along the c-axis, had good superconductivity, and could be prepared under all three atmospheres. The formation of the YBCO phase at high temperatures did not need oxygen, and subsequent low-pressure oxygen-annealing process was only required at low temperatures of about 350 ℃. Our findings are of great significance for the preparation and application of YBCO thin films on substrates that were easy to oxidize at high temperatures, such as nickel strips or some electronic printed circuit boards.