Nano-scale self-ordering in anodic porous alumina films and on electropolished aluminum surfaces has been studied. The Masuda process for pore ordering, consisting of a single cycle of long-time anodization plus stripping of the oxide layer, was extended to multi-cycle variant. A multi-cycle process increases the initial ordering rate, but as soon as the ordered domain area of 1-1.5 μm~2 is achieved, the ordering rate slows down, and does not depend on initial ordering. Long-time anodization improves the ordering; after 100 hours an ordering on 10x10 μm~2 size is demonstrated by 2D Fourier analysis. Electropolishing Al single crystals produce different topographies on different crystalline faces. For Al (110) highly ordered periodic stripes (periodicity 40-65 run, height 2-7 nm) covered the whole sample (area ≈1 cm~2). On Al (100) and Al (111) surfaces ordered topographies with hexagonal symmetry were obtained (periodicity 62-70 nm, height 5-10 nm), but only over 1-2 μm~2 domains.
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