TEM study of nanofinger structures for surface enhanced Raman scattering

Chemical sensing applications utilizing surface enhanced Raman spectroscopy (SERS) have drawn significant attention recently. However, developing a reliable, high performance SERS platform remains a challenge. A novel SERS substrate based on nanofingers was successfully demonstrated to provide large enhancement reliably and showed great promise for practical applications. Capillary forces bring the gold caps on the nanofingers into close proximity upon exposure to a solution containing molecules of interest, trapping molecules within the gaps and producing greatly enhanced Raman signals. Transmission electron microscopy (TEM) was used to characterize the structure of the nanofingers, in particular the gaps between finger tips to improve the fundamental understanding of the structural-performance relationship.