The discovery in 1974 of the enhancement of Raman scattering by molecules adsorbed on nanostructured metal surfaces is considered a landmark in the history of spectroscopic and analytical techniques. Much experimental and theoretical effort has been spent toward understanding the surface enhanced Raman scattering (SERS) effect, and demonstrating its potential toward various types of ultrasensitive sensing applications in a wide variety of fields. Forty five years later, SERS has blossomed as an extremely rich area of research and technology, but additional efforts are still needed before it can be routinely used as a commercial product. In this Review, prominent authors from all over the world joined efforts to summarize the current state-of-the-art in understanding and using SERS, as well as to propose what can be expected in the near future, in terms of research, applications, and technological development.

By positioning a single gold particle at different locations along the length axis on a cantilever based mass sensor, we have investigated the effect of mass position on the mass responsivity and compared the results to simulations. A significant improvement in quality factor and responsivity was achieved by operating the cantilever in the fourth bending mode thereby increasing the intrinsic sensitivity. It is shown that the use of higher bending modes grants a spatial resolution and thereby enhances the functionality of the cantilever based mass sensor.

Using a simple two step fabrication process substrates with a large and uniform Raman enhancement, based on flexible free standing nanopillars can be manufactured over large areas using readily available silicon processing equipment.