Article

Nanoimprint fabrication of gold nanocones with ~10 nm tips for enhanced optical interactions

Optoelectronics Research Centre, Tampere University of Technology, Department of Physics, Optics Laboratory, Tampere, Finland.
Optics Letters (Impact Factor: 3.18). 08/2009; 34(13):1979-81. DOI: 10.1364/OL.34.001979
Source: PubMed

ABSTRACT We show that nanoimprint lithography combined with electron-beam evaporation provides a cost-efficient, rapid, and reproducible method to fabricate conical nanostructures with very sharp tips on flat surfaces in high volumes. We demonstrate the method by preparing a wafer-scale array of gold nanocones with an average tip radius of 5 nm. Strong local fields at the tips enhance the second-harmonic generation by over 2 orders of magnitude compared with a nonsharp reference.

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    • "They may serve, for example, as anchor points for electro-optic active molecules, used for electrooptical devices. Usually, metal nanoparticle arrays are prepared by electron beam lithography [53] [54] [55] or photolithography [56] [57]. While electron beam lithography is time consuming and expensive, photolithography has lower limits concerning nanoparticle size. "
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