Influences of Ni–5 at.%W Alloy Substrates on the Epitaxial Growth and Surface Morphologies of CeO2 Films Deposited by PLD

Abstract

We fabricated CeO2 films using pulsed laser deposition (PLD) for YBa2Cu3O7−δ coated conductors on Ni–5 at.%W alloy substrates and investigated the effect of Ni–5 at.%W tapes on the epitaxial growth and surface morphologies of CeO2 deposited on various substrates at various temperatures ranging from 650 to 770 °C. The texture and microstructure of substrates and CeO2 films were measured by X-ray diffraction (XRD), optical microscope (OM), field emission scanning electron microscope (FESEM) and atomic force microscopy (AFM). It was found that the texture and microstructure of Ni–5 at.%W substrates, such as Ni(111), grain size, the depth of grain boundary grooves and surface roughness, affected the growth of CeO2 films. Especially, the depth of grain boundary grooves of substrates resulted in high intensity of CeO2(111) peak and high surface roughness of CeO2 films. We also found that high growth temperature effectively reduced the influence of substrate surface roughness on the epitaxial growth of CeO2 films. CeO2 films with high in-plane and out-of-plane alignments (Δφ=5.54°, Δω=3.40°) were obtained under optimum condition.