Fabrication of the YBCO Films Made by TFA-MOD Using the 211-Process

YBCO films were fabricated using TFA-MOD method with a precursor solution of and powders dissolved in trifluoroacetic acid (TFA) (the so called "211-film"). The effect of the calcining temperature on the phase formation, texture evolution, and thermal and critical properties were investigated. The microstructure and critical current density of the 211-film varied significantly with the calcining temperature. The highest of 1.9 (corresponding critical current is 39 A/cm-width) was obtained for the film calcined at 460, which is probably due to the enhanced degree of texture and increased film density and grain size. In addition, the microstructure and properties of the 211-films were compared with those of the film made using the conventional TFA-MOD method with the precursor of the acetates being dissolved in TFA. The of the 211-film was higher than that produced by the conventional TFA-MOD method. TG, DTA, pole-figure, and SEM analyses indicated that the higher was due to the improved microstructure resulting from the enhanced reaction kinetics in the 211-film.