Chalcogenide semiconductors as gas sensors

Abstract

A brief survey of experimental results to gas sensing with chalcogenide semiconductor based devices is given. It is pointed out that physical phenomena such as electrical conductivity can be coupled to chemical reactions on the surface or within the sensing material. Sensors based on tellurium alloys for detection of nitrogen dioxide, ammonia or carbon oxide are described in some detail. A general discussion is given about the fundamental mechanisms of gas sensing with these materials taking into consideration their special chemistry and defect states.