Effect of CeO2 buffer layer thickness on the structures and properties of YBCO coated conductors

Biaxially textured YBa2Cu3O7−x (YBCO) films were grown on inclined-substrate-deposited (ISD) MgO-textured metal substrates by pulsed laser deposition. CeO2 was deposited as a buffer layer prior to YBCO growth. CeO2 layers of different thickness were prepared to evaluate the thickness dependence of the YBCO films. The biaxial alignment features of the films were examined by X-ray diffraction 2θ-scans, pole-figure, ϕ-scans and rocking curves of Ω angles. The significant influence of the CeO2 thickness on the structure and properties of the YBCO films were demonstrated and the optimal thickness was found to be about 10 nm. High values of Tc = 91 K and Jc = 5.5 × 105 A/cm2 were obtained on YBCO films with optimal CeO2 thickness at 77 K in zero field. The possible mechanisms responsible for the dependence of the structure and the properties of the YBCO films on the thickness of the CeO2 buffer layers are discussed.