Improved Switching Performance of Nanoscale p-i-n Carbon Nanotube Tunneling Field-Effect Transistors Using Metal-Ferroelectric-Metal Gating Approach

Abstract

In this paper, the metal-ferroelectric-metal (MFM) gating design is used to boost the switching performance of the nanoscale p-i-n carbon nanotube (CNT) tunneling field-effect transistors (TFET). The modeling investigation is based on a rigorous computational approach that combines a self-consistent quantum simulation with the one dimensional Landau–Khalatnikov equation while considering ballistic transport conditions. The numerical results have revealed that the ferroelectric-induced amplified internal gate voltage is efficient in improving the switching performance of the p-i-n CNT tunneling FET. Particularly, the negative capacitance (NC) CNT tunneling FET has exhibited higher on-current, higher current ratio, steeper subthreshold swing, higher I60 factor, and faster intrinsic delay than those provided by the conventional design. In addition, the impact of the ferroelectric (FE) layer thickness on the switching figures of merit has also been assessed, where TFETs with thicker FE layers have exhibited more improved switching performance than those with thinner FE layers. The obtained results indicate that the MFM-based gating design can be an alternative improvement technique for ultrascaled p-i-n CNT tunneling FETs.