New miniaturized SAW-sensor array for organic gas detection driven by multiplexed oscillators

The use of sensor arrays with polymer-coated surface acoustic wave (SAW) devices as the key element for analytical sensor systems is a very promising technique for organic gas detection in process or quality control. In this work we present a new improved array of eight SAW sensors showing up reduced size, sampling volume and assembling costs. Moreover, its most important novelty is an in-built multiplexing technique which allow an automated and fast adjustment of the phase position of the SAW devices within the oscillators, respectively. This enables an easy optimization of the signal to noise ratio; expands the choice of coatings for the SAW sensors and improves the sensor to sensor reproducibility for a certain coating material. (C) 2000 Elsevier Science S.A. All rights reserved.