Carbon Nanotube Transistors as Gas Sensors: Response Differentiation Using Polymer Gate Dielectrics

The high sensitivity of carbon nanotube devices as gas sensors is generally attributed to the large surface area of the material. 

Francois Lapointe et al. demonstrate that bottom gate carbon nanotube network field-effect transistors (CNN-FETs) fabricated on a variety of polymer dielectrics, but with the same pristine carbon nanotubes, show differentiated responses to analytes. 

Scientists tested CNN-FETs with different polymer gate dielectrics against a series of analytes ranging from common alcohols to organic solvents and amines, among others. A rich set of distinct and complementary analyte signatures could be observed, identifying the polymer gate dielectric as a differentiator for chemical discrimination in a future printed cross-reactive sensor array, that is, an electronic nose.