High-aspect-ratio cylindrical nanopore arrays and their use for templating titania nanoposts

A method to prepare nanoporous templates has been demonstrated with controlled aspect-ratio and uniformity. The method used a top self-assembled layer for high silicon-containing etch mask and an underlying organic polymer layers. The study used spin-coating for thin self-assembled pattern layer on the transfer layer, while the pattern layer consists a polymethylsilixane resin and a diblock copolymer of polystyrene and poly(ehtylene oxide). The study also used a nanoporous films for templating the functional materials and the nanopores were filled with a chelated oligomeric titanate precursor (OT). It was observed that the direct contact of the PS microdomains with the transfer layer surface can improve the one-step oxygen plasma etching to remove the PS microdomains.