A study on fabrication of SERS substrates base on porous Si nanostructures and gold nanoparticles

In this report, we present a quick and straightforward approach to the fabrication of active-surface-enhanced Raman scattering (SERS) substrates based on gold nanoparticles (Au NPs) and porous silicon nanostructures (denoted by Si/Au substrate). SERS substrates were fabricated after 3-stage-process, including the Au NPs deposited on Si wafer, etching for porous Si wafer, and coating Au NPs on porous Si to produce SERS-active layers. Sputtering technique is used to coat Au NPs. The surface morphology of each Si/Au substrate in each fabrication process and their characteristics were examined in detail. The absorption spectrum of the Si/Au substrates exhibited a strong absorption band at 480 nm due to surface plasmon resonance of Au NPs. Using Si/Au substrates to detect Rhodamine B (RB) dispersed in ethanol showed that Si/Au substrates morphology greatly enhanced the Raman intensity of RB, and the trace detection limit for RB was estimated to be 0.5 ppm. This result opens up a promising approach to the use of SERS spectroscopy for food, environment, and pharmaceutics applications.Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.The authors and their respective affiliations have been correctly identified