Abstract
Bottom-up fabrication of nanopatterns with single nanometer-scale periodicity is quite challenging. In this study, we have focused on the use of the outermost convex surfaces of lyotropic liquid crystals (LLCs) as a template. Periodically arrayed single nanometer-scale nanogrooves consisting of silica are successfully formed on a Si substrate covered with LLCs composed of cylindrical micelles of cetyltrimethylammonium chloride. Soluble silicate species are generated from the Si substrate by a treatment with an NH3-water vapor mixture, infilling the interspaces between the Si substrate and the LLCs. The cross section of the nanogrooves has a symmetrical sawtooth-like profile with a periodicity of 4.7 nm, and the depth of each nanogroove is around 2 nm. Uniaxial alignment of the nanogrooves can be achieved using micrometer-scale grooves fabricated by a focused ion beam technique. Although formed nanogrooves contain defects, such as bends and discontinuities, this successful concept provides a novel fabrication method of arrayed concave patterns with sub-5 nm periodicity on the surfaces of Si substrates.
Original language | English |
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Pages (from-to) | 5160-5166 |
Number of pages | 7 |
Journal | ACS Nano |
Volume | 11 |
Issue number | 5 |
DOIs | |
Publication status | Published - 2017 May 23 |
Keywords
- liquid crystals
- nanoimprint mold
- nanopattern
- silicification
- template
ASJC Scopus subject areas
- Materials Science(all)
- Engineering(all)
- Physics and Astronomy(all)