Pulsed laser deposition of high critical current density YBa2Cu3O7−x/CeO2/Ni–W architecture for coated conductors applications

• Published in: Superconductor science & technology Vol. 16; no. 4; pp. 498 - 505
• Main Authors: Varesi, E, Celentano, G, Petrisor, T, Boffa, V, Ciontea, L, Galluzzi, V, Gambardella, U, Mancini, A, Rufoloni, A, Vannozzi, A
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.04.2003
• ISSN: 0953-2048; 1361-6668
• DOI: 10.1088/0953-2048/16/4/313

Epitaxial YBa2Cu3O7-x (YBCO) films with critical current densities exceeding 1 MA cm-2 (at 77 K in self magnetic field) were epitaxially grown on biaxially textured Ni 5 at% W (Ni-W) substrate using only a CeO2 buffer layer. Both YBCO and CeO2 films were deposited in situ by pulsed laser ablation. The oxidation behaviour of the Ni-W substrate enables the epitaxial growth of a CeO2 oxide buffer layer without using the forming gas (Ar 4%H2). SEM investigations of YBCO and CeO2 films reveal a dense microstructure without cracks or porosity. X-ray pole figures show a cube-on-cube epitaxy with a [100]YBCO//[110]CeO2 // [100]Ni-W epitaxial relationship. The YBCO superconducting film has a good out-of-plane and in-plane texture with a full-width-half-maximum of 5.8DG and 6.6DG, respectively. No severe degradation of JC with film thickness, up to 1 *mm thick films, was observed. The use of a single buffer layer on Ni-W substrates represents an important simplification in the scaling-up for long tape fabrication.