Abstract
The sensitive characteristics of surface-enhanced Raman scattering (SERS) can be applied to various fields, and this has been of interest to many researchers. Propagating surface plasmon resonance (PSPR) was initially utilized but, recently, it has been studied coupled with localized surface plasmon resonance that occurs in metal nanostructures. In this study, a new type of metal microstructure, named crater, was used for generating PSPR and Ag nanowires (AgNWs) for the generation of LSPR. A crater structure was fabricated on a GaAs (100) wafer using the wet chemical etching method. Then, a metal film was deposited inside the crater, and AgNWs were uniformly coated inside using the spray coating method. Metal films were used to enhance the electromagnetic field when coupled with AgNWs to obtain a high SERS intensity. The SERS intensity measured inside the crater structure with deposited AgNWs was up to 17.4 times higher than that of the flat structure with a deposited Ag film. These results suggest a new method for enhancing the SERS phenomenon, and it is expected that a larger SERS intensity can be obtained by fine-tuning the crater size and diameter and the length of the AgNWs.
Highlights
Surface plasmon resonance (SPR) is a phenomenon in which free electrons within the metal surface oscillate collectively when light is irradiated on the metal-dielectric interface [1,2]
To determine which metal film has high surface-enhanced Raman scattering (SERS) properties when combined with Ag nanowires (AgNWs), we prepared 2 nm thick Au and Ag films on GaAs (100) substrates, and 4 cm3 of AgNWs/ethanol dispersion was spray-coated on each sample
This indicates that the electric field is enhanced by the localized surface plasmon resonance (LSPR) generated in the gap between the AgNWs and Ag film
Summary
Surface plasmon resonance (SPR) is a phenomenon in which free electrons within the metal surface oscillate collectively when light is irradiated on the metal-dielectric interface [1,2]. There are several methods for generating SPR, such as making micro- and nano-sized holes [4,5] or creating a rough surface using nanoparticles [6,7], nanospheres [8,9], and nanowires [10,11] on metal films such as Ag and Au. The electric field is enhanced through resonance between the incident light source that has a specific wavelength, and either a sharp corner of the metal nanostructures or the narrow gap between the nanoparticles, which is called the “hot spot” [12]. Abutoama et al obtained ultra-high field enhancement through coupling localized and propagating surface plasmons by fabricating grating geometry structures and depositing nanoparticles [14]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
