Gas sensing characteristics of carbon nanotube gas sensor using a diaphragm structure

The micro-gas sensor based on carbon nanotubes (CNTs) was fabricated and its gas sensing characteristics on nitrogen dioxide () have been investigated. The sensor consists of a heater, an insulating layer, a pair of contact electrodes, and CNT-sensing film on a micromachined diaphragm. The heater plays a role in the temperature change to modify sensor operation. Gas sensor responses of CNT-film to at room temperature are reported. The sensor exhibits a reversible response with a time constant of a few minutes at thermal treatment temperature of .