Model of detection for a modulated conductivity sensor: application for a NOx gas sensor

The performance of a chemical gas sensor based on polycrystalline tin oxide films is strongly related to their structure, thickness and doping. In previous works we have studied the influence of the thickness on the detection by impedance spectroscopy analysis [1,2]. In the present work we have focused our attention in designing and modelizing a sensor for detection of NO
_x
for environmental applications. Reactive sputtered films with Al, In and Pt were characterized by complex impedance spectroscopy, Hall effect and d.c measurements.