Chalcogenide based sensitive layers for work function gas and humidity sensors

Abstract

In this work the authors report about characterization of chalcogenide based thin films, as a materials for gas – sensing applications. The sensing behavior of the As-S-Te-Ge films was tested with environmental pollutant gases such as NO2, CO, O3 and atmospheric humidity using the Kelvin probe technique at room temperature. A significant sensitivity has been observed for nitrogen dioxide. The detection range for NO2 was between 0.85 – 1.9 ppm in ambient air. The response and the recovery time are rapid with good reproducibility and high sensibility. The work function measurements showed, that chalcogenide semiconductors in question are well suited materials for the detection of not only small concentrations of NO2, but also for humidity sensing.