Current status of silicon carbide based high-temperature gas sensors

Abstract

Silicon carbide (SiC) based field effect gas sensors can be operated at very high temperatures. Catalytic metal-insulator-silicon carbide (MISiC) Schottky diodes respond very fast to a change between a reducing and an oxidizing atmosphere, and cylinder-specific combustion engine monitoring has been demonstrated. The sensors have also been suggested for high-temperature electronic nose applications. Car applications and other harsh environments put very strong requirements on the long-term stability of the sensors. Here we review the current status of the field of SiC based Schottky diode gas sensors with emphasis on the work in our group. Basic work on understanding of the detection mechanism and the influence of interfacial layers on the long-term stability of the sensors is reviewed. The direction of future research and device development in our group is also discussed.