The stability of Pt heater and temperature sensing elements for silicon integrated tin oxide gas sensors

Good performance of alarm systems and environmental as well as industrial c ontrol methods requires an optimal operation of the gas sensors involved. A n essential point related to this challenge is an accurate control of the s ensor working temperature. Therefore, the stability of the Ti/Pt heater ele ment used in tin oxide thin film gas sensors has been investigated. It turn s out that the heater element is influenced by diffusion and oxidation proc esses taking place during thermal treatment. This is illustrated by RES, AE S and XPS measurements. The modifications in chemical composition are also found to influence the electrical characteristics R-o and TCR of the heater . (C) 2000 Elsevier Science S.A Ail rights reserved.