Solid Phase (RE2BaO4)−Liquid Phase (BaCuO2) Reaction: The Way to Highly Oriented ErBa2Cu3Oy Superconducting Thick Films on Commercial Silver Substrates

Abstract

Using a solid phase−liquid phase reaction we developed a new technology for preparing c-axis oriented thick ErBa2Cu3Oy (Er-123) films on commercial polycrystalline silver substrates without the need for a buffer layer. The films were processed in Ar-1% pO2 atmosphere. Using a double-step annealing, thick Er-123 films were grown, with the onset Tc of about 92 K. Formation of large flat grains with the preferential c-axis orientation was confirmed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction. The magnetic self-field critical current density at 77 K was above 40 kA/cm2. This technology requires only a short processing time and thus is appropriate for utilization in long-length RE-123 silver-sheath wire production.