Sub-bands energy effect in the CNTFET chracteristics

Due to the rapid development of technology, the size of the transistor becomes smaller thus enable the production of sophisticated integrated circuit. Correspond to this objective, carbon nanotubes (CNT) has been seen as a potentially future material to provide an ultra small device by their exceptional electronic, optical, thermal, and mechanical properties. Among the many remarkable properties of nanotubes, we can mention 1D character that allows a good confinement of the charges and thus a good electrostatic control, which is essential in an application type transistor CNTFET (Carbon Nanotube Field Effect Transistor). The sub-band effects become significant and its effects have been studied in this research report. The band structure of the rolled-up nanotube can be obtained by zone-folding the band structure of the graphene sheet. This method is used in this work and we simulated electrical characteristics in order to show the influence of the three first sub-band energy in electrical characteristic of CNTFET.