Distribution of inductive J/sub c/ in two-dimensional large-size YBCO films prepared by fluorine-free MOD on CeO/sub 2/-buffered sapphire

Distribution of J/sub c/ in the two-dimensional large-size YBa/sub 2/Cu/sub 3/O/sub 7/ (YBCO) film was investigated by an inductive method for the application to fault current limiter elements. The YBCO films were prepared by metal-organic deposition (MOD) using a fluorine-free acetylacetonate-based complex solution on R-plane sapphire with an evaporated-CeO/sub 2/ buffer layer. The average J/sub c/ values of 1-3 MA/cm/sup 2/ at 77 K were obtained for 1 cm /spl times/ 12 cm-, 3 cm /spl times/ 12 cm-, and 10 cm /spl times/ 30 cm-rectangular YBCO films as well as on 2-inch-diameter films. In contrast with the TFA-MOD method via BaF/sub 2/ precursor, the fluctuation of J/sub c/ in the present films was fairly small; no significant size effects or shape effects were recognized on the fluctuation of J/sub c/. Instead, fluctuation of J/sub c/ depended on the average J/sub c/ values; higher-J/sub c/ films tended to exhibit more uniform J/sub c/ distribution.