Precursor evolution and growth mechanism of BTO/YBCO films by TFA-MOD process

In this study, BaTiO₃ (BTO)-doped YBCO films are prepared on LaAlO₃ (100) single-crystal substrates by metal-organic decomposition (MOD) using trifluoroacetate (TFA) precursor solutions. The critical current density (J_c) of BTO/YBCO film is as high as 10 MA/cm² (77 K, 0 T). The BTO peak is found in the X-ray diffraction (XRD) pattern of a final YBCO superconductivity film. Moreover, a comprehensive study of the precursor evolution is conducted mainly by X-ray analysis and μ-Raman spectroscopy. It is found that the TFA begins to decompose at the beginning of the thermal process, and then further decomposes as temperature increases, and at 700℃ BTO nanoparticles begin to appear. It suggests that the YBCO film embedded with BTO nanoparticles, whose critical current density (J_c) is enhanced, is successfully prepared by an easily scalable chemical solution deposition technique.