title: Using colloid lithography to fabricate silicon nanopillar arrays on silicon substrates.
abstract: In this study, we partially grafted geminal silanol groups in the protecting organic shells on the surfaces of gold nanoparticles (AuNPs) and then assembled the alkyl-AuNP-Si(OH)(4) particles onto the surfaces of silicon (Si) wafers. The density of assembled AuNPs on the Si surface was adjusted by varying the geminal silanol group content on the AuNP surface; at its optimal content, it approached the high assembly density (0.0254 particles/nm(2)) of an AuNP assembled monolayer. Using reactive-ion etching (RIE) with the templates as masks, we transferred the patterned AuNP assemblies to form large-area, size-tunable, Si nanopillar arrays, the assembly density of which was controlled by the dimensions of the AuNPs. Using this colloidal lithography (CL) process, we could generate Si nanopillars having sub-10-nm diameters and high aspect ratios. The water contact angles of the high-aspect-ratio Si nanopillars approached 150°. We used another fabrication process, involving electron beam lithography and oxygen plasma treatment, to generate hydrophilic 200-nm-resolution line patterns on a Si surface to assemble the AuNPs into 200-nm-resolution dense lines for use as an etching mask. Subsequent CL provided a patterned Si nanopillar array having a feature size of 200 nm on the Si surface. Using this approach, it was possible to pattern sub-10-nm Si nanopillar arrays having densities as high as 0.0232 nm(-2).
authors: Department of Materials Science and Engineering, National Taiwan University of Science and Technology, 43, Sec. 4, Keelung Road, Taipei 106, Taiwan, ROC. jkchen@mail.ntust.edu.tw
authors: Jem-Kun
authors: JK
authors: Chen
authors: Jia-Qi
authors: JQ
authors: Qui
authors: Shih-Kang
authors: SK
authors: Fan
authors: Shiao-Wei
authors: SW
authors: Kuo
authors: Fu-Hsiang
authors: FH
authors: Ko
authors: Chih-Wei
authors: CW
authors: Chu
authors: Feng-Chih
authors: FC
authors: Chang