The epitaxial oxidation of the (0 0 1)[1 0 0] textured Ni100-xVxtapes was studied because of the practical interest of NiO as a first buffer layer for the YBCO based coated conductors. The study revealed that the oxidation of the Ni-V alloy is rather complex, the less noble V being internally oxidized, while Ni undergoes an external oxidation. Moreover, the formation of the NiVO3and of Ni7V5O17compounds have negative effects on the epitaxial oxidation and on the surface morphology, as well. The role of vanadium on the epitaxial oxidation of Ni-V alloy has not been fully understood yet. The optimum conditions for the epitaxial oxidation have been found to be: 700<T<800°C, t<30 min and PO2<30 mTorr. The epitaxial NiO films obtained under these conditions have a good out-of-plane and in-plane orientation, with a full-width-half-maximum of about 6.5° and 9.5°, respectively. The in-plane epitaxial relationship is [1 0 0]NiO∥[1 1 0]Ni-V. The as-obtained films have a compact and crack-free morphology, with grain sizes ranging from 30 to 300 nm. Nevertheless, the NiO films grown on (1 1 3) oriented grains or on twins are polycrystalline with a bright aspect, exhibiting a spongeous morphology. Epitaxial YBCO/CeO2/NiO/Ni-V structures grown on the NiO template have a critical current density of about 0.6 MA/cm2at 77 K and zero magnetic field. © 2001 Elsevier Science B.V. All rights reserved.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering
Petrisor, T., Boffa, V., Celentano, G., Ciontea, L., Fabbri, F., Galluzzi, V., ... Varesi, E. (2002). Epitaxial oxidation of Ni-V biaxially textured tapes. Physica C: Superconductivity and its Applications, 377(1-2), 135 - 145. https://doi.org/10.1016/S0921-4534(01)01128-5