This thesis examines the fabrication of Au and Ag nanostructures for surface-enhanced Raman scattering (SERS) to improve molecular detection sensitivity. Silicon nanowire substrates were prepared and coated using magnetron sputtering on etched samples and LPCVD techniques. Raman measurements with 4-MBA and thiram show that signal intensity depends on concentration. Silver substrates outperform gold in sensitivity. LPCVD Ag structures achieved the lowest detection limits. The results confirm the effectiveness of nanostructured substrates for chemical sensing.