Highly Selective Sensing of DMMP and NH_3 Using CNTFET Based Gas Sensors Obtained using Spray-gun Technique and Fabricated with Different Metals As Electrodes

摘要

This paper deals with the fabrication of CNTFET obtained using carbon nanotube networks and with the utilization of these last as gas sensors. The method for depositing uniform and highly controlled density CNT mats is spray-gun technique. Using this technique we have demonstrated that we can achieve CNTFET with I_(on)/I_(Off) reproducible ratios of around 10~5/10~6. These transistors have been subsequently exposed to Acetic Anhydride which is a heroin precursor, showing a very short response time and a recovery time, without heating, of around 30 minutes. In this paper are also shown preliminary results after exposure of CNTFET to subppm concentrations of DMMP and NH, using two different metals as electrodes. In this case devices were obtained using drop-casting technique.