High performance surface-enhanced Raman scattering substrates of Si-based Au film developed by focused ion beam nanofabrication.

Content Provider	Europe PMC
Author	Gao, Tingting Xu, Zongwei Fang, Fengzhou Gao, Wenlong Zhang, Qing Xu, Xiaoxuan
Copyright Year	2012
Abstract	A novel method with high flexibility and efficiency for developing SERS substrates is proposed by patterning nanostructures on Si substrates using focused ion beam direct writing (FIBDW) technology following with precise thermal evaporation of gold film on the substrate. The effect of SERS on the substrate was systematically investigated by optimizing the processing parameters and the gold film thickness. The results proved that small dwell time could improve the machining accuracy and obtain smaller nanogap. The Raman-enhanced performance of the substrate was investigated with 10−6mol/L Rhodamine 6 G solution. It was indicated that the elliptic nanostructures with 15-nm spacing on Si substrates, coated with approximately 15-nm thick gold film, have exhibited a high-enhanced performance, but dramatic performance degradation was found as the gold film thickness further increased, which most probably resulted from changes of the nanostructures’ morphology such as elliptical tip and spacing. To avoid the morphological changes effectively after depositing gold film, optimization design of the nanostructures for FIBDW on Si substrates was proposed. Besides, a similar phenomenon was found when the gold film was less than 15nm because there was little gold remaining on the substrate. The method proposed in this paper shows a great potential for the higher performance SERS substrates development, which can further reduce the spacing between hot spots.
ISSN	19317573
Journal	Nanoscale Research Letters
Volume Number	7
PubMed Central reference number	PMC3502558
Issue Number	1
PubMed reference number	22804810
e-ISSN	1556276X
DOI	10.1186/1556-276x-7-399
Language	English
Publisher	Springer
Publisher Date	2012-07-17
Access Restriction	Open
Rights License	This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Copyright ©2012 Gao et al.; licensee BioMed Central Ltd.
Subject Keyword	SERS Si-based Au nanostructures Focus ion beam nanofabrication Thermal evaporation
Content Type	Text
Resource Type	Article
Subject	Nanoscience and Nanotechnology Condensed Matter Physics Materials Science