High Production Rate Process of YBCO Coated Conductors by TFA-MOD Process

Influence of process conditions including water vapor partial pressure, gas flow rate and total annealing pressure on YBa₂Cu₃O_7-y (YBCO) film growth has been investigated in order to clarify the YBCO growth mechanism and to increase the growth rate. YBCO films have been fabricated on a LaAlO₃ substrate by metalorganic deposition (MOD) process using tri- fluoroacetates (TFA) as a solute source. It was found that the processing parameters such as high water partial pressure, high diffusion constants due to low total pressure, and high gas flow rate affect the YBCO growth rate. Furthermore, it was empirically suggested that the growth rate of the YBCO film was in proportion to both the square root of water partial pressure and gas flow rate and was in inverse proportion to the one sixth power of the total pressure. The YBCO growth rate of about 2 times as fast as the previous condition was achieved with high performance by optimizing the process parameters.