Fabrication of highly oriented YBa2Cu4O8 films by alkoxide sol–gel methods

Abstract

YBa₂Cu₄O₈ films were fabricated on MgO(100) single‐crystal and Ag substrates at atmospheric pressure by the sol–gel method using metal alkoxides. On MgO(100) substrates, YBa₂Cu₄O₈ films were formed at 800 °C through YBa₂Cu₃O_7−x. On Ag substrates, YBa₂Cu₄O₈ films were obtained at a firing temperature as low as 700 °C and highly oriented films were formed at 800 °C. YBa₂Cu₄O₈ films were not formed through YBa₂Cu₃O_7−x in this case. Simultaneous use of the sol–gel method and Ag substrates was remarkably effective for promoting the formation of the YBa₂Cu₄O₈ phase and producing highly oriented films.