GROWTH OF YBA2CU3O7-X SUPERCONDUCTING THIN-FILMS ON [111]ORIENTED AG FILMS

YBa2Cu3O7-x(YBCO) superconducting thin film was prepared on a [111] or iented Ag film using off-axis rf magnetron-sputtering. The [111] orien ted Ag film was prepared on the (001) single-crystal natural mica subs trate at a substrate temperature of 200 degrees C under argon atmosphe re. The YBCO film grew with, not only a strong orientation far the c-a xis, but also with the three-symmetrical orientation for a and b axes on the mica/Ag substrate without post-annealing, The full-width at hal f maximum (FWHM) intensity of the 003 omega-rocking curve of the YBCO film was 1.52 degrees The optimal substrate temperature nas 620 degree s C, when the partial pressure of oxygen was 1.0 x 10(-2) Torr, T-C (o nset) and T-C (zero) of the films were 84 K and 77 K, respectively, ac cording to the AC magnetic susceptibility measurements, The J(C) of th e film was measured by the conventional four-probe method, and the J(c ) (J//ab) value was 1.4 x 10(4)A/cm(2) at 77 K in a liquid nitrogen ba th. The YBCO film showed the thickness dependence of T-c to be due to the large lattice mismatch of Ag(111) to YBCO (001).