Formation of oxidation-resistant Cu-Mg coatings on (001) Cu for oxide superconducting tapes

✍ Scribed by K.H. Kim; D.P. Norton; D.K. Christen; J.D. Budai

• Book ID: 104094290
• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 589 KB
• Volume: 202
• Category: Article
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2008.05.026

✦ Synopsis

The formation of oxidation-resistant buffer layers on (001) oriented Cu for coated high-temperature superconducting tape applications was investigated. The approach employed Cu/Mg multilayer precursor films that were subsequently annealed to form either Mg-doped fcc Cu or intermetallic Cu 2 Mg. The precursor consisted of an Mg/Cu multilayer stack with 5 each of 25 nm thick Mg and 25 nm thick Cu layers which were grown at room temperature by sputter deposition. At annealing temperature of 400 °C, formation of the intermetallic Cu 2 Mg was observed. X-ray diffraction showed that the Cu 2 Mg (100) oriented grains were epitaxial with respect to the underlying Cu film, possessing a cube-on-cube orientation. In order to test oxidation resistance, CeO 2 films were deposited at elevated temperature on Ni/(Cu,Mg)/Cu/MgO structures. In case of the CeO 2 film on Ni/Cu/MgO, significant surface roughness due to the metal oxidation is observed. In contrast, no surface roughness is observed in the SEM images for the CeO 2 /Ni/(Cu,Mg)/Cu/MgO structure.