REPRODUCIBLE GROWTH OF HIGH-QUALITY YBA2CU3O7-X FILM ON (100) MGO WITH A SRTIO3 BUFFER LAYER BY PULSED LASER DEPOSITION

Epitaxial YBa2Cu3O7-x(YBCO) films were grown on SrTiO3-buffered (100) MgO substrates by pulsed laser deposition. The SrTiO3 layer of about 500 angstrom thick serves a dual purpose to provide a better lattice match to the YBCO films as well as a diffusion barrier to prevent interaction between YBCO and MgO. These YBCO films exhibit excellent structural, electrical, and microwave properties with T(c) > 89 K and T(c) = 2.9 X 10(6) A/cm2 at 77 K (1 X 10(6) A/cm2 at 84 K). X-ray pole figure measurements showed that over 99.92% of the volume fraction of the c-axis oriented film has the a-b axis aligned parallel to the [010] and [001] direction of the substrate.