Improving chemical solution deposited YBa2Cu3O 7-δ film properties via high heating rates
Physica C: Superconductivity and its Applications
The superconducting and structural properties of YBa2Cu 3O7-δ (YBCO) films grown from chemical solution deposited (CSD) metallofluoride-based precursors improve by using high heating rates to the desired growth temperature. This is due to avoiding the nucleation of undesirable a-axis grains at lower temperatures, from 650 to 800 °C in p(O2) = 0.1%. Minimizing time spent in this range during the temperature ramp of the ex situ growth process depresses a-axis grain growth in favor of the desired c-axis orientation. Using optimized conditions, this results in high-quality YBCO films on LaAlO3(100) with J c(77 K)∼3 MA/cm2 for films thicknesses ranging from 60 to 140 nm. In particular, there is a dramatic decrease in a-axis grains in coated-conductors grown on CSD Nb-doped SrTiO3(100) buffered Ni(100) tapes. © 2003 Elsevier B.V. All rights reserved.