Multiwall carbon nanotube gas sensor fabricated using thermomechanical structure

Abstract

We address a multiwall carbon nanotube (MWCNT) gas sensor that has an enhanced reproducibility. The sensor consists of a heater, an insulating layer, a pair of contact electrodes, and an MWCNT-sensing film on a micromachined diaphragm. The heater plays a role in the temperature changes to modify the rates for desorption of gases on the sensing surface during sensor operation. Gas sensor responses of MWCNT-film to NO2 at room temperature are reported. We show that the sensor exhibits a reversible response with a time constant of a few minutes at thermal treatment temperature of 130 degrees C.