Abstract
In this paper we will present the main patents in the domain of the Carbon Nanotubes Field Effect Transistors (CNTFETs) based gas sensors. Although these devices have allowed to achieve sensors with an impressive sensitivity, compared to existing technologies, the physical interpretation of the effect of interaction between the gas molecules and the CNTFETs has not been clarified yet. This is pointed out not only by the scientific papers issued in the last years in the domain but also by the patents that have been filled. Considering that the selectivity is the main issue for this kind of devices, we will focus our analysis on the different routes that have been proposed in patents to overcome this problem : carbon nanotubes functionalization using polymers or biomolecules (e. g. DNA), electrodes metal diversification and metal decoration of Single-Walled-Carbon-NanoTubes (i.e. SWCNTs) mats. We will discuss about the physics behind each approach and we will try to compare them.
Keywords: SWCNT, CNTFET, nanosensors, nanotechnology, gas sensing