Fabrication of Large-Scale Patterned Gold-Nanopillar Arrays on a Silicon Substrate Using Imprinted Porous Alumina Templates

摘要

We demonstrate the fabrication of large scale nano- and micropatterned gold-nanopillar arrays at predefined positions on a silicon substrate. Our method employs an imprinted porous alumina layer as a template film for electrodeposition. The stamps for the imprinting procedure are formed by a standard lithographic process combined with wet-chemical etching of silicon. This method facilitates the fabrication of large-scale stamps displaying defined nano- and microstructures without the use of electron-beam (e-beam) lithography. The stamp pattern is transferred onto a thin gold/aluminum film covering a silicon substrate. Anodization of the imprinted aluminum film generates nanochannels that connect to the underlying gold surface selectively at the indented regions. Patterned areas of Au nanopillars are created by electrochemical deposition of gold inside the nanochannels and subsequent dissolution of the alumina membrane. The pattern can be controlled by the stamps geometry, while the diameter, density, and height of the pillars are determined by the anodization conditions and thickness of the aluminum film.