Nature of dopants and effects on sensitivity of SnO2 based gas sensor

Abstract

In this work, a thick film SnO2 sensor was fabricated on a 1′ × 1′ alumina substrate. It consists of a gas sensitive layer (SnO2 ) doped with Pd and Pt; a pair of electrodes in array form underneath the gas sensing layers serves as a contact pad for sensor and a common heater element on the backside of the substrate. Alumina substrate (96%) has been used as a substrate for sensor fabrication. The fabricated sensor was tested for varying concentration of LPG and methane in a locally developed test chamber. The response of sensors to varying concentration of LPG and methane was studied at 350° C. The Pd-doped sensor was found to be more sensitive towards LPG and methane.