Composite chemical sensors based on carbon-filled patterned negative resists

Conductometric chemical sensors based on polymer composite films, synthesized by adding conductive fillers to the polymer solutions and deposited between two predefined electrodes, are well established. Deposition of the sensitive composites is usually applied to sensor devices by solvent casting methods such as spin coating, spray coating and drop casting. These methods lack in pattern precision and repeatability. In order to overcome pertinent problems the application of conventional patterning methods for the fabrication of the conductive sensing array is proposed. In this work, we present the deposition of two conductive polymer composites poly(dimethylsiloxane)/carbon black and epoxy polymer/carbon black on the same substrate. Each polymer composite is deposited onto two respective electrodes, effectively creating a conductive polymer chemical sensor pair. The two sensors performance is evaluated and considered as a first step towards the fabrication of a conductometric polymer composite array. Electrical vs dimensional sensitivity issues and the significance of electrode configuration are considered.