Focused ion beam production of nanoelectrode arrays

We present a method for the production of nanoelectrodes using focussed ion beam techniques (FIB). The electrodes utilise nanometric holes milled in a silicon nitride based pasivation layer, followed by wet etching of a silicon oxide based pasivation layer, to expose an underlying gold electrode. After functionalisation using a surface assembled monolayer and an electrochemically grown polypyrrole, these gold nanoelectrodes have been tested, via cyclic voltammetry, in the detection of Fe(CN)(6) ions. The nanoelectrodes will be used to investigate the electrical properties of nanometric biological specimen. (c) 2007 Elsevier B.V. All rights reserved.