Chemical method to prepare YBa2Cu3O7−x (YBCO) films by dipping onto SrTi(Nb)O3 ceramics

Superconductor films of YBa2Cu3O7−x (YBCO or 123) were formed by dip-coating onto SrTiO3 and Nb-doped SrTiO3 ceramic substrates. The precursor solution was based on Y-acetate, Ba-alcoholate in 2-methoxyethanol and Cu-butyrate, in an alcoholic solvent. Different heat treatments, up to a maximum temperature of 870°C, were performed under oxygen and nitrogen atmosphere. The films onto Nb-doped SrTiO3 ceramic exhibit less reaction with the substrate as well as better superconducting properties. The best superconducting properties (Tc,onset = 91 K) were obtained in YBCO films, which were initially treated under N2 flow up to 625°C, then under O2 up to 870°C, and subsequently reheated thoroughly under oxygen atmosphere with an annealing at 450°C.