Texture and surface analysis of NiO buffer deposited on biaxially textured Ni tapes by a MOCVD method

NiO buffer layers for YBCO coated conductors were deposited on textured Ni substrates by a metal-organic chemical vapor deposition(MOCVD) method. Processing variables were the oxygen partial pressure and substrate temperature. The degree of texture and the surface roughness of the deposited NiO surface were analyzed by X-ray pole figure, atomic force microscopy (AFM), and scanning electron microscope (SEM). The (200) textured NiO layer was formed at 450 ~ 470 (degree)C and oxygen partial pressure of 1.67 Torr. Out-of-plane((omega)-scan) and in-plane((Phi)-scan) texture were 10.34(degree) and 10.00(degree), respectively. The surface roughness estimated by atomic force microscopy was in the range of 3.1 ~ 4.6 nm which was much smoother than that prepared by an oxidation method. We discuss the development of the (200) texture in the MOCVD-NiO films in terms of processing variables.