Abstract: | One of the most widely used methods for surface‐enhanced Raman scattering (SERS) employs silver or gold nanoparticles either in colloidal suspension or in the dry‐drop form. In such substrates the SERS amplification factors depend critically on the interparticle distances. Here, we report that microwave absorption as a function of temperature in dry‐drop substrates can be used as a probe to demarcate temperature regions for thermal annealing to produce SERS substrates with very high amplification factors. Copyright © 2011 John Wiley & Sons, Ltd. |