Preparation and Superconducting Properties of Highly Oriented Thick Films of Y-Ba-Cu-O Systems by a Paint-on Method

The highly oriented films of Y-Ba-Cu-O systems have been prepared on polycrystalline YSZ substrates by a paint-on method. Superconducting properties of these thick films were examined as a function of the particle size of pastes and postprinting annealing conditions. The X-ray diffraction patterns after appropriate heat treatments showed that the highly oriented c- axis was perpendicular to the substrate surface. The orientation was also confirmed by a SEM observation and a magnetization measurement. The typical film of 50 ?m thickness showed zero resistance around 90 K. The critical current density of the highly oriented film was 36 and 882 A/cm2 at 77 and 5 K, respectively. The mechanism of the orientation was composed of two steps.