Towards nanowire (bio) sensors

Abstract

Nanowire based electrochemical devices represent a new and emerging class of sensors. In this work, we fabricate gold nanowires with well controlled critical dimensions using hybrid-electron beam lithography. Individual nanowire electrodes are routinely fabricated and are easily electrically contacted using overlay electrodes. Following fabrication, nanowire device performance is assessed using both electrical and electrochemical characterization techniques. We observe low electrical resistances (∼ 900 Ω) with typical linear Ohmic responses from fully packaged nanowire devices. Steady-state cyclic voltammograms in ferrocenemonocarboxylic acid demonstrate scan rate independence up to 1000 mV s-1 with low interfacial capacitance. The applicability of these nanowire electrodes for sensing was explored using square wave voltammetry.