Preparation of Epitaxial YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7−y</sub> Films and CeO<sub>2</sub> Buffer Layer on Ni-5at.%W Substrates by MOD Method

Abstract

Biaxially textured CeO2 films were deposited on Ni–5at.%W (Ni–5W) tapes by a metal-organic deposition (MOD) method. Subsequent YBa2Cu3O7-y (YBCO) films were prepared using the (MOD) method leading to a simplified coated conductor architecture of YBCO/CeO2/Ni–5W. X-ray diffraction measurements revealed an epitaxial growth of the CeO2 buffer layer the 7.06°, 5.16°, for the out-of-plane and in-plane alignment, respectively. The superconducting coated film with a texture spread down to the out-of-plane texture is ω = 6.2° and the in-plane texture is φ = 7.6°. The results indicate that single CeO2-buffered Ni–5W tapes are suitable for the epitaxial growth of YBCO higher cube texture and the epitaxial YBCO film was obtained. To microstructural investigations, the film’s SEM results showed a dense, smooth and crack-free surface morphology. The superconducting properties were measured by four probe method. The superconducting transition temperature (Tc) was about 90 K with a narrow transition of 0.8 K and the critical current density (Jc) was about 1.5×104 A/cm2 at 77 K, 4T.