Modelling of Carbon NanoTube Field Effect Transistors oriented to simulation software: applications to A/D circuit design

In this chapter we analyze a compact, semi-empirical model of Carbon Nanotube Field Effect Transistors (CNTFETs) directly and easily implementable in simulation software. The model is based on the hypothesis of fully ballistic transport in a mesoscopic system between two non-reflective contacts and analytical approximations are introduced to avoid the resort to self-consistency. A new procedure, based on a best-fitting between the measured and simulated values of output device characteristics, is proposed. This procedure allows to extract, from the measured output characteristics of the device, the optimal values of the CNTFET equivalent circuit elements. To verify the versatility of the proposed model, we use it in circuit simulators to design some electronic circuits. In particular we investigate about the effects of the CNT quantum resistances and inductances, then demonstrating their role for both analog and digital applications at frequencies over about ten THz.