Nanostructured gold-coated AFM tips generated by potentiostatic electrodeposition for tip-enhanced Raman spectroscopy

Potentiostatic electrodeposition was used to manufacture gold-coated atomic force microscopy (AFM) tips for applications in tip-enhanced Raman spectroscopy (TERS). The growth of the gold film was found to be initiated by the instantaneous nucleation mechanism on the doped-silicon AFM tip taken as substrate. This cost-effective method allowed robust AFM-TERS probes with localized surface plasmon resonances in the visible range to be produced with 53 % yield. These probes enable TERS mapping of a graphene oxide flake and a carbon nanotube to be performed with lateral spatial resolution below 20 nm, which was uncorrelated with the curvature radius of the metallized tip apex.