Boosting the performance of an ultrascaled carbon nanotube junctionless tunnel field-effect transistor using an ungated region: NEGF simulation

摘要

This paper focuses on the role of the longitudinal spacing between the auxiliary gate and control gate in boosting the performance of an ultrascaled junctionless carbon nanotube tunnel field-effect transistor (JL CNT-TFET). The investigation is based on self-consistent quantum simulations in the nonequilibrium Green's function formalism in the ballistic limit. It is found that dilation of the ungated longitudinal space between the gates causes a significant improvement in the leakage current, ambipolar behavior, subthreshold swing, on/off-current ratio, power-delay product, and intrinsic delay. In addition, a substantial enhancement in the swing factor and current ratio is also recorded for the JL CNT-TFET with coaxial control gate length below 10 nm. The results indicate that adjusting the spacing between the auxiliary gate and control gate is a simple, efficient, and promising approach to achieve ultrascaled JL CNT-TFETs with very high performance.