Deposition of CeO₂ and NiO buffer layers for YBCO coated conductors on biaxially textured Ni substrates by a MOCVD technique

CeO₂ and NiO buffers for YBCO coated conductors were deposited on biaxially textured Ni substrates by a metal-organic chemical vapor deposition method. The degree of texture and surface roughness of the oxide films were analyzed by X-ray pole figure, atomic force microscope (AFM) and scanning electron microscopy. The texture of deposited CeO₂ films was a function of deposition temperature and oxygen partial pressure (P_O2). The (200) texture of CeO₂ was fully developed at T = 500-520 °C and P_O2 = 3.33 Torr. The growth rate of the CeO₂ films was 200 nm/min at T = 520 °C and P_O2 = 2.30 Torr, which is much faster than those prepared by other physical deposition methods. The (200) texture of NiO was formed at T = 450 °C and P_O2 = 1.67 Torr. The full width half maximum of the both films was in the range of 8-10°. The AFM surface roughness of the films was between 3.0-10 nm, depending on the deposition temperature.