2. Amplifying surfaces

Little described in the literature, signal-amplifying thin films are once again in the spotlight thanks to the current craze for nanotechnologies. Their role in optical instrumentation, in particular, means that equipment previously limited to characterizing microstructures can now be used to analyze structures of nanometric dimensions.

Signal-amplifying surfaces are made up of thin and/or microstructured layers that transform the basic characteristics of the substrate to increase the signal intensity of the sample being analyzed. These amplifying surfaces boost the performance of nanometric characterization tools. In this sense, they are often referred to as "intelligent" surfaces, and their development is seen as strategic for the years to come. Today, these specific surfaces are used in particular in the fields of label-free biological analysis and Raman spectroscopy....