High-resolution transmission electron microscopy/analytical electron microscopy characterization of epitaxial oxide multilayers fabricated by laser ablation on biaxially textured Ni

Microstructural characterization of rolling-assisted biaxially textured substrates (RABiTS) was conducted using high-resolution transmission electron microscopy (TEM) and high-resolution analytical electron microscopy (AEM). RABiT substrates with a multilayer configuration YSZ (0.2 mu m)/CeO2 (0.9 mu m)/Ni (125 mu m) were studied. The substrates were fabricated by epitaxial deposition of oxide layers using laser ablation on biaxially textured Ni substrates. High critical current density YBa2Cu3Ox thick films have been fabricated on such RABiT substrates and typically yield J(c) values over 1 MA/cm(2). TEM examinations show that a reaction layer 10-40 nm thick is formed at the CeO2/Ni interface. Detailed microstructural and chemical analyses indicate that the layer is epitaxial {001} nickel oxide on {001} Ni. The CeO2 layer is found to consist of three distinct morphologies corresponding to the growth atmosphere during the deposition. The YSZ layer exhibited a columnar structure aligned along the [100] axis, with little or no orientation variation between the columns. The interface between the YSZ and CeO2 layers is atomically sharp and neither interdiffusion of elements nor an interfacial reaction layer is observed, Implications of these results on processing are discussed. (C) 1999 Published by Elsevier Science B.V. All rights reserved.