ИСТИНА

Here, we present the results of examination of 3D porous structure of anodic alumina films formed on low-index and vicinal planes of Al single crystals under self-ordering conditions using the combination of small-angle X-ray scattering and statistical analysis of SEM images. The in-plane orientational order and the mosaicity of AAO porous structure are completely predetermined by the symmetry of the Al surface subjected to anodization. The Al(111) substrate with the 6-fold rotation axis normal to the surface is prone to the formation of hexagonally ordered areas on a large scale, while the 4-fold symmetry of the Al(100) substrate leads to a large number of completely misoriented small domains. The inclination of channels from the normal to the metal surface on the vicinal planes is explained by the competitive impact of electromigration driving force and the crystallographic anisotropy of the substrate. It was also shown that pores growing in different directions during anodization retain hexagonal domains with various in-plane orientations. These results for the first time demonstrate the strong correlations between the longitudinal alignment and in-plane packing options of pores in anodic alumina films.