In this paper we describe the fabrication of a periodic, two-dimensional arrangement of gold square patches on a Silicon substrate, and highlight technological limitations due to the roughness of the metal layer. Scanning Electron Microscope (SEM) and Atomic Force Microscope analyses are also reported showing that the geometrical parameters obtained are almost identical to the nominal parameters of the simulated structure. The device is functionalized by means of a conjugated rigid thiol forming a very dense, closely packed, reproducible 18 angstrom-thick, self-assembled monolayer. The nonlinear response of the 2D array is characterized by means of a micro-Raman spectrometer and it is compared with a conventional plasmonic platform consisting of a gold nano-particles ensemble on Silicon substrate, revealing a dramatic improvement in the Raman signal. The SERS response is empirically investigated using a laser source operating in the visible range at 633 nm. SERS mapping and estimation of the provided SERS enhancement factor (EF) are carried out to evaluate their effectiveness, stability and reproducibility as SERS substrate. Moreover, we take advantage of the simple geometry of this 2D array to investigate the dependence of the SERS response on the number of total illuminated nano-patches
Nonlinear response of 2D plasmonic gold patches for SERS applications / Grande, M.; Petruzzelli, V.; D'Orazio, A.; Vincenti, M. A.; de Ceglia, D.; Bianco, G. V.; Bruno, G.; Stomeo, T.; De Vittorio, M.; Scalora, M. (PROCEEDINGS OF SPIE, THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING). - In: Plasmonics : metallic nanostructures and their optical properties X / [a cura di] Mark I. Stockman. - STAMPA. - Bellingham WA : The international society for optics and photonics, 2012. - ISBN 978-0-8194-9174-9. [10.1117/12.929474]
Nonlinear response of 2D plasmonic gold patches for SERS applications
M. Grande;V. Petruzzelli;A. D'Orazio;M. A. Vincenti;D. de Ceglia;
2012-01-01
Abstract
In this paper we describe the fabrication of a periodic, two-dimensional arrangement of gold square patches on a Silicon substrate, and highlight technological limitations due to the roughness of the metal layer. Scanning Electron Microscope (SEM) and Atomic Force Microscope analyses are also reported showing that the geometrical parameters obtained are almost identical to the nominal parameters of the simulated structure. The device is functionalized by means of a conjugated rigid thiol forming a very dense, closely packed, reproducible 18 angstrom-thick, self-assembled monolayer. The nonlinear response of the 2D array is characterized by means of a micro-Raman spectrometer and it is compared with a conventional plasmonic platform consisting of a gold nano-particles ensemble on Silicon substrate, revealing a dramatic improvement in the Raman signal. The SERS response is empirically investigated using a laser source operating in the visible range at 633 nm. SERS mapping and estimation of the provided SERS enhancement factor (EF) are carried out to evaluate their effectiveness, stability and reproducibility as SERS substrate. Moreover, we take advantage of the simple geometry of this 2D array to investigate the dependence of the SERS response on the number of total illuminated nano-patchesI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
