PREPARATION OF SUPERCONDUCTING BA2YCU3O7-Y FILMS BY THE DIPPING-PYROLYSIS PROCESS AT 700-DEGREES-C AND 750-DEGREES-C

Superconducting Ba2YCu3O7-y (BYCO) films were prepared by the dipping-pyrolysis process using metal acetylacetonates as starting materials through heat treatments below 800-degrees-C under controlled low oxygen partial pressures (p(O2)'s) followed by O2 annealing. Values of T(c, zero) (r)'s were greatly dependent on the temperature and p(O2) of heat treatment; they were 64 K and 85 K with the heat treatments at 700-degrees-C, respectively, under an initial p(O2) of 2 x 10(-4) atm for 2-mu-m-thick BYCO films. Moreover, silver precoating was effective for improving the superconducting and surface properties of the films heat-treated at 700-degrees-C.