Thin Film Semiconducting Metal Oxide Gas Sensors

Abstract

As far as security and environmental protection are concerned, the specifications are more and more severe, and require the development of highly sophisticated regulation and control systems. To this end, the development of gas sensors, associated with microelectronic technology and data processing, allows the realization of systems which can be used as alarms for gas detection or regulation. The large field of applications of gas sensors, the realization of portable systems and the necessity of developing multisensor systems (“electronic noise”) by mean of a pattern recognition method, require cheap sensor devices with low power consumption. The development of thin film gas sensors based on semiconducting metal oxides appears in this context as a possible answer because of the full compatibility of the modern techniques of deposition with the microelectronic technology. Then, it is possible to realize miniaturized gas sensors and, by using micromachining, to develop thermally isolated structures with a small level of power consumption. Moreover, the batch process fabrication assures good reproducibility and a low cost.