Microstructure Formation Process of Y123 Film Fabricated by Advanced TFA-MOD Process

In order to clarify the growth process of the Y123 film on LAO or CeO₂/LAO in the modified TFA-MOD process using precursor solution of TFA salts for Y and Ba and F-free salt for Cu, two methods were introduced. The quenching method revealed the growth process of Y123 crystals during the process by observing the microstructures of the quenched film by TEM. Also the in-situ observation of the sample-surface revealed the generation of liquid and/or gas in YBCO film during the process, and pores were considered to form by the gas passed through the liquid phase. A growth model for Y123 crystals in YBCO film with some process-controlling parameters was obtained on the basis of the above observed results. The growth processes of faceted Y123 crystals with various crystal orientations were simulated by two-dimensional numerical method using c-axis and a-axis growth rate functions.