Authors: P. Bondavalli, P. Legagneux and D. Pribat
Affilation: THALES, France
Pages: 29 - 32
Keywords: nanotube, Chemical detection, nanosensors
The first paper showing the great potentiality of Carbon Nanotubes Field Effect transistors (CNTFET) for gas sensing applications was published in 2000. From this moment a lot of scientific teams have focused their interest on this new kind of sensors. These devices exploit the extremely sensitive change of the Schottky junction built up between carbon nanotubes (CNT) and drain/source metal electrodes : the gas change the metal work function and so the bending and the height of the Schottky barrier. Actually the principal issue selectivity. This paper deals with a new approach which should allow the quick and selective detection of different gas. Actually we propose to realize an array of CNFET transistors where each device is obtained using different contact metals (drain/source). Each gas will change the work function of metal electrodes in a very specific way and will thus modify the CNTFET electrical characteristics. With this approach we can obtain a highly detailed electronic fingerprinting of the gas. Moreover gas molecules desorption could be easily achieved using UV light exposition or with thermal anneal without failing to degrade the device performances. Results concerning exposition of a matrix of CNTFET with different metals contacts to DiMethyl-Methyl-Phosphonate (simulant for sarin gas) in environmental conditions will be presented during the meeting for proof-of-concept demonstration of our device.