Fabrication of gold tips suitable for tip-enhanced Raman spectroscopy

The authors report on a simple method of fabricating gold tips, suitable for use in a shear-force mode atomic force microscope for tip-enhanced Raman spectroscopy (TERS). The proposed electrochemical method is highly optimized and offers five advantages: produces a low-aspect ratio tip that can withstand the lateral force at the end of the tip during scanning, produces a sharp tip end to generate good Raman enhancements for TERS, a self-terminating process that makes the etching process easy, use of inexpensive electronic systems so that it can be adopted by any laboratory, and less time consuming (takes less than 20s to fabricate a single tip). This article demonstrates TERS imaging using such tips.