A grazing-incidence small-angle X-ray scattering view of vertically aligned ZnO nanowires

Abstract

We report a grazing-incidence small-angle X-ray scattering study of ZnO films with vertically aligned and randomly distributed nanowires, grown through a hydrothermal growth process on nanostructured ZnO seeding coatings and deposited by electron beam evaporation on silicon and glass, respectively. The comparison of the scattering patterns of seeding coatings and nanowires showed that the scattering of vertically aligned nanowires exhibited a specific feature: the dominant characteristic of their scattering patterns is the appearance of fine structure effects around the specular peak. These effects were clarified by the combined reflection and scattering phenomena, suggested for the aligned nanowires-substrate system. Furthermore, they enabled the calculation of the average gyration radius of nanowires in horizontal direction. The calculated value was in good agreement with the radii of nanowires estimated by surface electron microscopy. Therefore, the observed feature in the scattering pattern can serve as evidence of the aligned growth of nanowires. © 2013 M. Lučić Lavčević et al.