Preparation and Characterization of DyBa₂Cu₃O_y Thick Films with Dy₂BaO₄ Precursor

DyBa₂Cu₃O_y (Dy-123) thick films were fabricated from Dy₂BaO₄, BaCuO₂, and CuO powders. We have added 0, 1, 2, and 4 wt% of Ag₂O. Mixture of alpha-terpineol and 2-ethyl acetate was used as a solvent, to which 100nm-sized stoichiometric powdered mixture was added and grinded for several hours to form a highly dense paste. Thick film precursors were prepared by spreading the paste on MgO substrates with a screen printing technique. The films were sintered with a double-step annealing process. The Dy-123 thick films obtained were of good quality. XRD analyses confirmed the formation of a high-quality c-axis oriented Dy-123 for films annealed at 1070^oC for 10 min and at 880^oC for 2 h. Scanning electron microscopy showed the formation of large flat grains. Onset T_c was 91 K according to magnetization measurements. The present results suggest that this process might be useful for the preparation of large-area superconducting thick films on MgO substrates in a short processing time.