DESIGN OF A SILICON MICROSENSOR ARRAY DEVICE FOR GAS-ANALYSIS

This paper describes the design of a silicon-based microsensor array f or application in gas or odour monitoring. Individual sensor cells con sist of both lateral and vertical electrode pairs to measure film cond uctance and/or capacitance. The fabrication process involves standard silicon technologies to integrate a platinum or nickel-iron heater bel ow the sensor cells. A simulation of the device gives a thermal respon se time of only 60 ms and an ultra low power loss of about 50 mW at 40 0 degrees C per sensor. This compares well with experimental values ob served on a similar device. The process technology is suitable for bot h the deposition of organic materials (e.g. conducting polymers) and i norganic materials (e.g. semiconducting oxides). A scheme of the trans ducer interface circuitry is also provided, and could be used in a por table battery-powered instrument. (C) 1996 Elsevier Science Ltd.