Influence of water vapor and illumination on conductivity of tin dioxide thin films at room temperature

Abstract

Investigation results of water vapour and illumination influence on the conductivity of tin dioxide thin film based gas sensors are presented. According to literature it is known that water vapor has a donor effect on the conductivity of the tin dioxide (n-type semiconductor), i.e. its conductivity in the water vapor atmosphere increases. It was experimentally found that the presence of water vapor in the measuring chamber leads to an increase in the conductivity of the sensor (in the dark) or to a decrease in conductivity (when the active layer of the sensor is illuminated).

Keywords

• gas sensors
• thin films
• tin dioxide
• acceptor action of water vapor