Growth mechanism of Y123 film by MOD-TFA process

Growth process of Y123 crystal grains in the film fabricated by TFA–MOD method

“…The bright region is unreacted region composed of amorphous (which was liquid or amorphous at the firing temperature) and precipitates (Y 2 Cu 2 O 5 , BaF 2 , CuO, etc.) [9]. In this case, the left side of the a-axis grain does not meet c-axis grain yet, and the width of this grain is larger than the above mentioned slim a-axis grains.…”

“…The faceted Y123-crystal growth was simulated from the liquid (or amorphous) + oxide and fluoride particles (Y 2 Cu 2 O 5 , CuO, BaF 2 ) [9,[20][21][22] in the precursor film during the firing. The above particles in the film were assumed to compose the composite-particles (Y 3 Ba 3 Cu 4 O x F y ) in the liquid of Ba 3 Cu 5 O 8 (Y, F), and the initial distribution of the composite particles was given as the lognormal distribution.…”

“…Metal organic deposition (MOD) process using precursor solution of trifluoroacetates (TFA) for Y and Ba and F-free salt for Cu is one of the promising low cost non-vacuum methods to fabricate high-J c coated conductors [1][2][3][4][5][6][7][8][9]. Since the microstructures of superconducting YBa 2 Cu 3 O 7ÀX (Y123) crystals affects the properties of the multi-coated film, it is very important to know the crystal growth process to obtain high-J c film.…”

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

“…However, it has some problems such as low-Jc in the thick films [6], [8], which has worse Y123-crystal alignment and/or micro cracks. Since Y123 phase grows in the precursor film with , and CuO by the release of HF with supplying [9], liquid/gas evolution affects the growth process, microstructure and properties of Y123 film. However, details of the growth mechanism of Y123 crystals are still unknown.…”

Single crystal growth and physical properties of carbonsubstituted YBa 2 Cu 3 O 7– δ

“…For these problems, the exact amounts of substituted carbon and the substitution effects on physical properties were unknown. Given the recent importance of TFA-MOD methods in practical application [6], the relationship between carbon substitution and superconductivity should be clarified.…”