Deposition of potential Y2-xBixO3 buffer layers for YBCO coated conductor

Abstract

Potential Y2-xBixO3 (x = 0.8, 0.9, 1, 1.1, and 1.2) buffer layer for YBCO coated conductor has been deposited on the LaAlO3(100) substrate via a chemical solution deposition route. For the sample with x = 1, which has the best lattice match with YBCO, YBCO thin film has been deposited using MOD method. XRD θ-29 scan reveals an excellent c-axis alignment for both Y2-xBixO3 and YBCO. ∅-scan and co-scan show good in-plane and out-of-plane texture for both YBiO3 and YBCO layer. A dense, homogeneous, pinhole-free and crack-free morphology has been observed for Y2-xBixO3 through ESEM images. Influence of thermal process on the epitaxial growth as well as the microstructure of the deposited buffer layer has been discussed. The dense and smooth YBCO film exhibit a sharp superconducting transition at around 90 K as well as a Jc > 2 MA/cm2 at 77 K and self-field. This work offers a new approach to search for better lattice matched buffer layer materials for YBCO or even REBCO.