Characterization of textured NiO films for application as buffer layers in high temperature superconducting tapes

Abstract

Textured NiO films have been grown, by thermal oxidation, on biaxially textured Ni substrates. The films have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The XRD results showed two texture components, cube texture (001)[100] and (111) with out of plane orientation only. SEM showed much inhomogeneity of grain size on the sample surface. Analysis by EBSD revealed that coarse grained regions were cube textured and fine grained regions were <111> fibre textured. The ability to correlate textural and microstructural data is crucial to the optimization of textured NiO films for use in coated conductor technology.

Application of electron backscatter diffraction to the study of phase transformations

“…(i) rough areas with coarse cube or {111} textured grains and smaller, possibly faceted 'intergranular' grains (ii) smooth regions having the desired epitaxial cube or rotated cube texture (Woodcock et al, 2002a(Woodcock et al, , 2002b(Woodcock et al, and 2004).…”

Combinatorial substrate epitaxy: a new approach to growth of complex metastable compounds

“…Electron backscatter diffraction (EBSD) is an appropriate characterization tool, having been developed over the course of the last few decades for the complete quantification of crystallographic distributions in polycrystalline microstructures. [37][38][39][40] EBSD has been used for film characterization, [41][42][43][44][45][46][47] though less commonly than for bulk specimens, and has been sparsely used for epitaxial film growth. 21,[48][49][50][51][52] We recently demonstrated using CSE that the phase and orientation relationship of TiO 2 films on BaTiO 3 51 and BiFeO 3 35 polycrystals could be probed over a spread of orientation space using just one polycrystalline substrate.…”

Crystal orientation mapping of NiO grown on cube textured Ni tapes

“…The major advantage of EBSD over XRD, that textures of individual microstructure components can be measured, is shown clearly here. Both of the above orientation relationships have been previously reported in Ni/NiO (Matsumoto et al ., 1999; Woodcock et al ., 2002a; Lockman et al ., 2003).…”

“…Electron backscatter diffraction (EBSD) facilitates spatial correlations between texture and microstructure and has proved valuable in many fields of study (Randle, 1992). Some initial results showing crystal orientation maps (COMs) of NiO have been published (Woodcock et al ., 2002a,b) but poor resolution and image quality limited the effectiveness of the results. Further optimization of the technique of EBSD on NiO layers has been carried out and new results are presented which enable direct correlation of textures and microstructures of the oxide grown on textured Ni substrates.…”