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Title: Laser-nanostructured Ag films as substrates for surface-enhanced Raman spectroscopy

Abstract

Pulsed-laser (248 nm) irradiation of Ag thin films was employed to produce nanostructured Ag/SiO{sub 2} substrates. By tailoring the laser fluence, it was possible to controllably adjust the mean diameter of the resultant near-spherical Ag droplets. Thin films of tetrahedral amorphous carbon (ta-C) were subsequently deposited onto the nanostructured substrates. Visible Raman measurements were performed on the ta-C films, where it was observed that the intensity of the Raman signal was increased by nearly two orders of magnitude, when compared with ta-C films grown on nonstructured substrates. The use of laser annealing as a method of preparing substrates, at low macroscopic temperatures, for surface-enhanced Raman spectroscopy on subnanometer-thick films is discussed.

Authors:
; ;  [1]
  1. Nano-Electronics Centre, Advanced Technology Institute, School of Electronics and Physical Sciences, University of Surrey, Guildford GU2 7XH (United Kingdom)
Publication Date:
OSTI Identifier:
20778688
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 88; Journal Issue: 8; Other Information: DOI: 10.1063/1.2178387; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMORPHOUS STATE; ANNEALING; CARBON; DROPLETS; IRRADIATION; LASERS; NANOSTRUCTURES; RAMAN SPECTROSCOPY; SIGNALS; SILICON OXIDES; SILVER; SUBSTRATES; THIN FILMS

Citation Formats

Henley, S.J., Carey, J.D., and Silva, S.R.P. Laser-nanostructured Ag films as substrates for surface-enhanced Raman spectroscopy. United States: N. p., 2006. Web. doi:10.1063/1.2178387.
Henley, S.J., Carey, J.D., & Silva, S.R.P. Laser-nanostructured Ag films as substrates for surface-enhanced Raman spectroscopy. United States. doi:10.1063/1.2178387.
Henley, S.J., Carey, J.D., and Silva, S.R.P. Mon . "Laser-nanostructured Ag films as substrates for surface-enhanced Raman spectroscopy". United States. doi:10.1063/1.2178387.
@article{osti_20778688,
title = {Laser-nanostructured Ag films as substrates for surface-enhanced Raman spectroscopy},
author = {Henley, S.J. and Carey, J.D. and Silva, S.R.P.},
abstractNote = {Pulsed-laser (248 nm) irradiation of Ag thin films was employed to produce nanostructured Ag/SiO{sub 2} substrates. By tailoring the laser fluence, it was possible to controllably adjust the mean diameter of the resultant near-spherical Ag droplets. Thin films of tetrahedral amorphous carbon (ta-C) were subsequently deposited onto the nanostructured substrates. Visible Raman measurements were performed on the ta-C films, where it was observed that the intensity of the Raman signal was increased by nearly two orders of magnitude, when compared with ta-C films grown on nonstructured substrates. The use of laser annealing as a method of preparing substrates, at low macroscopic temperatures, for surface-enhanced Raman spectroscopy on subnanometer-thick films is discussed.},
doi = {10.1063/1.2178387},
journal = {Applied Physics Letters},
number = 8,
volume = 88,
place = {United States},
year = {Mon Feb 20 00:00:00 EST 2006},
month = {Mon Feb 20 00:00:00 EST 2006}
}
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