Optimization of annealing conditions in oxide-precursor-based MOD process for YBCO thin films

A low cost YBCO oxide powder was employed as a starting precursor for MOD process. YBCO oxide is advantageous over metal acetates or TFA salts which are popular starting precursors for conventional MOD-TFA process because that YBCO oxide precursor is cheap and easy to control molar ratio. YBCO thin films were prepared by this oxide-precursor-based MOD process and annealing condition was optimized. The YBCO thin film annealed at below 780 degree C shows no transport Ic and poor microstructure. Raman spectroscopic study of YBCO thin film indicates that YBCO thin film prepared at below 780 degree C contains a number of imperfections such as non-superconducting BaCuO2 phase, cation disorder, etc. However, the YBCO thin film treated at above 800 degree C shows improvement in microstructure and current transport properties. This research was supported by a grant from Center for Applied Superconductivity Technology of the 21st Century Frontier R and D Program funded by the Ministry of Science and Technology, Republic of Korea.