Optical properties of ordered Dot-on-Plate nano-sandwich arrays

A cost-effective fabrication method for realizing ordered Dot-on-Plate nanostructure array is presented. This fabrication method is a combination of Nanoplastic forming (NPF) and thermal dewetting, which does not involve costly and complicated processes such as lithography. The fabricated Au-SiO2-Au sandwich nanostructures exhibit double plasmon resonances and strong magnetic response, which makes it a potential candidate for metamaterials. It is also found that the Dot-on-Plate nanostructure shows good performance as surface-enhanced Raman scattering (SERS)-active substrate. The milling of SiO2 spacer layer by dry etching is studied and the relation between the plasmonic properties and SERS enhancement is discussed. (C) 2014 Elsevier B.V. All rights reserved.