Effect of CNTs Parameter Variation on the Performance of Analog Device

Carbon nanotubes (CNTs) have emerged as a prominent material for present day nano-scale systems design. In spite of their widespread use in biology, and nano-electro mechanical systems (NEMS, CNTs have encroached upon conventional MOSFETs for the design of low power and high speed circuits. Because CNT possesses higher current carrying capability, higher transconductance and near ballistic transport of charge carriers. The diameter of the CNTs laid from the Source to the Drain in a CNFET has the significant influence on the characteristics of the device itself as well as on the features of circuits implemented using the said CNFET. Such variations in circuit parameters with CNT diameter can be shown to be more pronounced in analog circuits as compared to digital CNFET-based designs. The present work attempts to investigate the effect of diameter variation on a versatile analog building block (ABB) viz. the inverting current conveyor. It is demonstrated that various parameters of the ICC-II under scrutiny, like voltage bandwidth, current bandwidth, average power dissipation, etc. depend on the diameter of CNT(s) used in the CNFETs. HSPICE simulations performed on a 0.9V; 32nm CNFET-based ICC-II are included to exemplify the dependencies studied.