Stability Analysis in CNTFETs

We present a Nyquist stability criterion, together with step time responses, for the small-signal equivalent circuit model of common-source-configured carbon-nanotube (CNT) field-effect transistors (CNTFETs) made of 100 CNTs at 10-nm pitch as well as single CNTs, for the first time. In this analysis considering tube-to-tube variations in CNTs´ diameters, dependence of the degree of relative stability on CNT dimensions is acquired. Simulations show that the step responses for both types of CNTFETs, unlike those for CNT/GNR-based local interconnects, pose multiharmonic oscillations. Amplification of such harmonics by CNTFET can cause instability.