Thin carbon films as electrodes for bioelectronic applications

Thin film diamond-like carbon (DLC) electrodes were fabricated by radio frequency (RF) magnetron sputtering on silicon, silicon oxide, and platinum substrates. The dependence of physical and electrochemical properties on process parameters like temperature, pressure, and incident power was investigated. We deposited carbon layers with hydrogen concentrations below 1%. Therefore, the resistivity was minimized to a value of 30 m Ohm cm. The low surface roughness of all DLC films leaded to a small double-layer capacity of 37 mu F/cm(2). A large electrochemical bandwidth and a nearly ideal reversibility was shown and compared to the properties of conventional glassy carbon electrodes. The applicability of the DLC electrodes to electrochemical investigations and bioelectronic applications was demonstrated. (C) 1998 Elsevier Science S.A. All rights reserved.