Porous anodic alumina and pillar titania structures have been fabricated and used for the vertical alignment of nematic liquid crystals (LCs). Reliable LC penetration into pores was achieved for a pore entrance of more than 20 nm in width. The LC penetration into pillar structures has no restrictions owing to the absence of closed pore spaces. The aspect ratios of titania pillars ranged from 2 up 6, the maximum of which was limited by the mechanical stability of the fabricated pillars. The approaches developed are useful in fabricating LC projection displays.

A method to fabricate tubular nanoporous alumina layers by anodization of aluminum at current densities up to 1400 mA/ cm 2 and anodization rates up to 70 m / min has been developed. It implies anodization in the meniscal region of the sample dipping into an electrolyte. The formed porous alumina has been found to be selforganized nanotube cells when the anodization current excides 100 mA/ cm 2. The formation of nanotubes is supposed to be controlled by the increased volume expansion factor ͑more than 2͒ at high forming current densities. The meniscal anodization allows fabrication of porous alumina nanotubes with desired tilt angles in the range of 0°-16°.

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