10.1021/nn1017507.s001
Seungwoo Lee
Seungwoo
Lee
Jonghwa Shin
Jonghwa
Shin
Yong-Hee Lee
Yong-Hee
Lee
Jung-Ki Park
Jung-Ki
Park
Fabrication of the Funnel-Shaped Three-Dimensional Plasmonic Tip Arrays by Directional Photofluidization Lithography
American Chemical Society
2010
Directional Photofluidization LithographyPlasmonics
plasmonic light enhancement
nanofabrication technique
photofluidization lithography
plasmonic tip
tip features
nanofunnel tips
nanophotonic applications
fabrication method
EM field enhancement
2010-12-28 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Fabrication_of_the_Funnel_Shaped_Three_Dimensional_Plasmonic_Tip_Arrays_by_Directional_Photofluidization_Lithography/2702149
Plasmonics allow localization of an electromagnetic (EM) field into nanoscale “hotspots”, a feature that is of technological significance due to potential applications related to spectroscopic sensing and nanofocusing. In relation to this, many researchers have sought to fabricate metallic nanostructures with sharp edges, as they provide much higher EM field enhancement compared with rounded structures. However, a fabrication method satisfying stringent requirements for the efficient EM field enhancement including three-dimensionality, vertical orientation, large-area fabrication, and tunability of structural features, which are of practical importance for efficient plasmonic light enhancement at hotspots, has yet to be achieved. Herein, we fabricate large-area, vertically aligned three-dimensional plasmonic tip (<i>i.e.</i>, nanofunnel) arrays with unprecedented flexibility in the control of the structural features by directional photofluidization lithography. Using this approach, the structural features of nanofunnel tips including the sharpness, shape, and orientation were precisely controlled in a scalable and deterministic manner. The effects of the structural features of the nanofunnel on the EM field enhancement were systematically investigated and analyzed, and the optimum tip features for maximum EM field enhancement were thereupon identified. The suggested nanofabrication technique and resulting structures will be of practical importance in spectroscopic and nanophotonic applications.