Design of Si0.45Ge0.55-based core–shell-type dual-material dual-gate nanotube TFET with source pocket technique

In this paper, dual-material dual-gate nanotube TFET (DMDG-NTTFET) is proposed. Dual gates in this regard are of the core–shell type, and dual-gate materials (GM 1 and GM 2 ) are used as control gate having work functions of φ tunnel and φ Auxiliary , respectively. The device is further explored with source pocket and various underlap gate lengths. When device characteristics are compared with the conventional NWTFET, significant improvements in I ON , I OFF , I ON /I OFF , transconductance (g m ), recombination rate, and transconductance factor (g m /I d ) are observed. The proposed structure also results in improved linearity and tunnelling in the device. The effects of the device variables, such as φ tunnel , φ Auxiliary , source pocket length (L 1 ), gate underlap length (L 2 ), and molar concentration in Si 1-x Ge x (x), on various analog performance indicators, such as transconductance factor (g m /I d ), transconductance (g m ), unity gain cut-off frequency (f T ), intrinsic device delay ( τ ), transconductance frequency product ( g m / I d ∗ f T ), and gain–bandwidth product (GBWP), have been investigated. The I ON and I ON /I OFF in source pocket dual-material dual-gate nanotube TFET (SPDMDG NTTFET) is improved by a factor of 21.11 and 846.12, respectively. The subthreshold slope achieved using the proposed structure is 18.28 mV/decade.