Interdigitated microelectrode arrays based on sputtered carbon thin-films

Thin-film carbon microelectrodes deposited by RF sputtering onto a Si/Si3N4 substrate are presented. By optimizing the deposition parameters, films showing low resistivity (10(-3) Omega cm) and good adhesion are achieved. Physical, spectroscopic and electrochemical characterizations are carried out. The electrocatalytical properties of the carbon thin-films are assessed with and without surface activation. Successful patterning in O-2 plasma is demonstrated by the fabrication of interdigitated microelectrode arrays featuring a resolution of 2 mu m. The analytical performance of the interdigitated microelectrodes is illustrated by the detection of dopamine over a concentration range of 50 nM to 100 mu M.