Open AccessHigh signal collection efficiency in a 3D SERS chip using a micro-reflector
Author(s) -
Feng Yang,
Ping Wen,
Zhiqiang Zhang,
Li Danyang,
Chen Li,
Shunbo Li
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.410966
Subject(s) - materials science , rhodamine 6g , raman spectroscopy , wafer , raman scattering , isotropic etching , optics , optoelectronics , substrate (aquarium) , surface enhanced raman spectroscopy , deep reactive ion etching , reflector (photography) , silicon , signal (programming language) , etching (microfabrication) , nanotechnology , reactive ion etching , computer science , light source , oceanography , physics , layer (electronics) , geology , fluorescence , programming language
To improve the sensitivity of surface-enhanced Raman spectroscopy (SERS) detection, we propose a three-dimensional (3D) SERS chip based on an inverted pyramid micro-reflector (IPMR) that converges Raman scattering light signals to improve the signal collection efficiency. The influence of the geometric parameters of the inverted pyramid structure on the Raman signal collection efficiency was analyzed by simulation for the determination of the optimal design parameters. The inverted pyramid through-hole structure was prepared on the silicon wafer through an anisotropic wet etching process, followed by the sputtering of a gold film to form the IPMR. The 3D SERS chip was constructed by bonding the IPMR and the active substrate that assembled with silver nanoparticles. Using Rhodamine 6G molecules, the Raman intensity measured with the 3D SERS chip was threefold greater than that of the silicon-based SERS substrate under the same test conditions. These experimental results show that the 3D SERS chip can significantly improve the SERS signal intensity. Its 3D structure is convenient for integration with microfluidic devices and has great potential in biochemical detection applications.