Abstract
Raman scattering is an excellent analysis tool because a wealth of information can be obtained using a single measurement. It can also be configured as a diagnostic tool as a label free sensing method. In that case, enhancing the Raman signal is important to improve the sensitivity and detect low concentrations of analytes. A nanoparticle showing a particular Raman enhancement shows a much higher enhancement when it is on a nanowire. This was also confirmed experimentally. We report on a simple fabrication method of silver nanoparticles and silicon nanowires decorated with these nanoparticles. The nanowires were fabricated using metal assisted chemical etching. The nanoparticles were formed using electrodeposition. Samples were then immersed in Pyridine. An enhancement factor of around 6 to 8x10(5) was observed for silver nanoparticles alone. By depositing the same nanoparticles on silicon nanowires, the enhancement factor jumped 10-fold to 7x10(6). Finite Difference Time Domain simulations showed that a range of enhancement factors is possible up to 10(9).