Efficient SERS substrates based on laterally ordered gold nanostructures made using interference lithography.

Laterally ordered gold nanoisland arrays made using interference lithography has been investigated in this work as SERS substrates. The developed substrates demonstrate performance in enhancing Raman signal of common dye analyte (crystal violet (CV)) comparable to commercial SERS substrates, with the lowest detectable concentration of CV ~10⁻⁶…10⁻⁷ M. They can be reused after heat treatment at 300 °C without any drop of performance. Furthermore, we found a principal difference in the effect of annealing of SERS substrates before deposition of the analyte molecules and additional in situ annealing (with molecules) on the intensity of Raman signal. Possible physical origin of the latter effect has been discussed. [ABSTRACT FROM AUTHOR]