DYBA2ZRO5.5 - A NEW PEROVSKITE CERAMIC SUBSTRATE FOR YBCO AND BI(2223) SUPERCONDUCTOR FILMS

A new ceramic material DyBa2ZrO5.5 has been synthesized and sintered a s single-phase material for use as a substrate for both YBa2Cu3O7-delt a and (Bi, Pb-2)Sr2Ca2Cu5O10+delta superconductors. DyBa2ZrO5.5 has a complex cubic perovskite structure (ABB'O-6), with a lattice constant a = 8.462 Angstrom. The dielectric constant and loss factor are in a r ange suitable for its use as a substrate for microwave applications. Y BCO and Bi(2223) superconductors did not show any detectable chemical reactivity (within the precision of the x-ray diffraction technique) w ith DyBa2ZrO5.5, even under severe heat treatment. The dip-coated thic k films of YBCO on polycrystalline DyBa2ZrO5.5 substrate gave a T-c(0) of 92 K and a critical current density (J(c)) of 3 x 10(4) A cm(-2) a f 77 K. A dip-coated Bi(2223) thick film on DyBa2ZrO5.5 substrate gave a T-c(O) of 110 K and a current density 4 x 10(3) A cm(-2) at 77 K.