Gas sensing applications of novel semiconductor materials

Abstract

Recent trends in research on gas sensors based on semiconducting thin films are presented. The films, all deposited by RF reactive sputtering from metallic targets, are investigated by the volt-amperometric technique for electrical and gas-sensing properties. The layers were able to sense CO and NO/sub 2/. No surface poisoning effect was recorded, and resistance recovery was complete. Concentrations as low as 0.5 ppm NO/sub 2/ and 15 ppm of CO were detected with a high relative change in the resistance and a fast dynamic. A detection limit lower than 100 ppb of NO/sub 2/ is expected.