A large volume reduction and calcining profile for large-area YBa₂Cu₃O_7 xfilm by metalorganic deposition using trifluoroacetates

Abstract

We have routinely obtained high critical current density (J c ) YBa 2 Cu 3 O 7−x (YBCO) film by metalorganic deposition using trifluoroacetates (TFA-MOD). This method requires a relatively long calcining process of 9-17 h to obtain the optimal J c for 0.15 nm thick film. To apply this method to long wires and tapes, we need to know the thickness dependence of the calcining condition. We found that the optimal time of about 10 h was independent of the final thickness of 150, 180 or 240 nm. Furthermore, the results imply that the chemical reaction during the calcining process was decomposition and that a large-area film could be calcined with the same profile as used for a short one. We successfully calcined seven YBCO films using this profile on 10 × 10 mm LaAlO 3 single crystals in a line. All fired films were 156-188 nm thick and had J c of 5.53-6.73 MA cm −2 (77 K, 0 T) as measured by the four-probe method.

Progress in Nanoengineered Microstructures for Tunable High‐Current, High‐Temperature Superconducting Wires

“…This is a common feature of these MOD films, even with variations in the composition of the precursors. [69][70][71] An important point to make here is that the chemistry, composition, and thickness of the precursor are not independent variables with respect to producing crack-free, high-performance MOD films. The evaluation of new precursor materials continues to be an area of intense research, especially with regards to the development of thick YBCO films.…”

“…The evaluation of new precursor materials continues to be an area of intense research, especially with regards to the development of thick YBCO films. [25,69,72] …”

Ethanol-based TFA–MOD method for preparation of YBCO films

“…1. The film reveals a homogeneous and dense surface, similar to the typical TFA-MOD YBCO films [4,10].…”

“…Growth mechanism and influence of various processing parameters for TFA-MOD method have been widely investigated [8][9][10][11][12][13][14]. However, to our knowledge, little attention has been paid to the effect of solvent used for precursor solution preparation.…”

“…Methanol is the most commonly used solvent in TFA-MOD route [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. It is toxic and may cause death or blindness [15], which would involve serious health risk for industrial manufacture.…”