Study of Surface-Enhanced Raman Scattering of Rhodamine 6G from repeated dewetted gold thin film

This study reports the fabrication of gold nanoislands by thermal dewetting of gold thin film deposited on a silicon wafer to study the SERS of Rhodamine 6G molecules at an ultra-low concentration. It provides a comparative study of single dewetting and repeated dewetting, showing that repeated dewetting provides ten times higher SERS enhancement than the other. Repeated dewetting reduces the gap between the particles and increases the number of plasmonic hotspots. We analyzed the SERS by using DI water and ethanol as the solvent for R6G, using a laser excitation of 532 nm. We also reported the single-molecule detection of the R6G molecule using our SERS substrate. This simple fabrication method of SERS substrate can be used in the future to detect analytes at a single-molecule regime.