Fabrication of SnO2 based CO gas sensor device using thick film technology

Abstract

This research was aimed at fabricating a CO gas sensor based on SnO2 material synthesized using sol-gel method. The sensor components include thin film gold electrode and a PdAg heater screen printed on the backside of the alumina substrate. The device was tested to study the effect of temperature variation on the resistivity of the heater component, and the response of the SnO2 sensitive layer to 10 ppm CO gas. The SnO2 layer was characterized using SEM and EDS to determine the morphology and composition of the material. It was found that the SnO2 sensitive layer contained 21.21% C atoms, 22.43% O atoms, 14.98% Si atoms, 0.34% Cr atoms, 1.16% Ag atoms, 1.78% Sn atoms, and 38.11% Au atoms. The sensor sensitivity to CO gas increased with increasing temperature. The Operational temperature of this sensor was 95° C with the highest sensitivity value obtained was 16.59.