title: Constant current etching of gold tips suitable for tip-enhanced Raman spectroscopy.
abstract: We introduce a setup and method to produce gold tips that are suitable for tip-enhanced Raman spectroscopy by using a single step constant current electrochemical etch. The etching process is fully automated with only three preset parameters: the etching current, the reference voltage and the immersed length of gold wires. By optimizing these parameters, reproducible high quality tips with smooth surface and a radius curvature of about 20 nm can be formed. Tips prepared with this method were examined by tip-enhanced Raman spectroscopy experiments on the samples of single-wall carbon nanotube, p-aminothiophenol, and graphene. In the Raman mapping of single-wall carbon nanotubes, the spatial resolution is about 15 nm.
authors.affiliation: Suzhou Institute of Nano-tech and Nano-bionics, CAS, Suzhou 215123, People's Republic of China.
authors.forename: Gengzhao
authors.initials: G
authors.lastname: Xu
authors.forename: Zhenghui
authors.initials: Z
authors.lastname: Liu
authors.forename: Ke
authors.initials: K
authors.lastname: Xu
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Haijian
authors.initials: H
authors.lastname: Zhong
authors.forename: Yingmin
authors.initials: Y
authors.lastname: Fan
authors.forename: Zengli
authors.initials: Z
authors.lastname: Huang