Synthesis of superconducting films of the Y-Ba-Cu-O system by a screen printing method

A screen printing method has been used to deposit superconducting films of Y-Ba-Cu-O materials on Al2O3 substrates. The electrical resistivity, microstructure, and adhesion of these films are highly sensitive to the post-printing heat treatment. Films heat treated at 950 °C and below are poorly adherent, whereas those annealed above 1000 °C undergo phase separation to Y2Cu2O5 and BaCuO2 and also react with the substrate. Nearly single phase, highly adherent, and smooth films showing a zero resistance state at 79 K have been synthesized by optimizing the annealing conditions.