Self-consistent analysis of Carbon NanoTube (CNT) transistors: state-of-the-art and crytical discussion

With this contribution we attempt to synthesize the recent developments in modeling carbon nanotubes by means of analytical approaches. The starting point is provided by an approximate self-consistent model of nano-FETs, currently proposed in the literature: our task is to apply this technique in order to obtain all significant quantities related to the nano-transistor operation, such as charge diffusion, transmission probability of carriers through the channel and current-voltage characteristics. Moreover, we develop a critical discussion about the real limitations of this approach, by analyzing its implicit assumptions. We highlight that the effective mass approximation is consistent with the nanotube characterization, but is conventionally extended also to the metal region. Further limiting assumptions are given by the cylindrical symmetry of charge and potential and by the single-mode description of the charge transport through the channel.