Improved Superconducting Performance of YBCO-Coated Conductors by Low Energy Density Argon Ion Etching

The a -axis grains and other secondary phase impurities, which are of great suppression for the superconducting properties, are easily formed on the surface of YBa 2 Cu 3 O 7-δ (YBCO)-coated conductors (CCs) prepared by trifluoroacetic acid metal organic deposition (TFA-MOD) method. Removal of these impurities is crucial to improve superconductivity and further applications. In this paper, low energy density argon ion etching method is proposed to modify the surface properties of YBCO films by removing the surface layer without damaging the epitaxial structure. It is an effective strategy to regulate the internal strain, oxygen content and Cu–O chains of YBCO films. It is demonstrated that the self-field critical current density ( J c ) of the ion etched samples can be enhanced compared with the pristine one via this surface treatment. Meanwhile, the etching time is a crucial parameter to modify J c values.