Improved Electrostatic Performance of Hetero Oxide and Work-function Modulated Ferro Tunnel Field Effect Transistor for Low Power Applications

Abstract

The present work suggests and examines a hetero-oxide, dual-metal, negative-capacitance, double-gate tunnel field-effect transistor (HDM-NC-DGTFET) to achieve improved electrostatic control, ON-state current, and analog/RF characteristics to low-power applications. The suggested architecture combines (i) dual metal gate work-function engineering (φ₁ < φ₂), (ii) hetero-gate dielectric arrangement, and (iii) a ferroelectric covering to produce negative capacitance voltage amplification. The low-work-function gate at the source-channel interface not only sharpens the band bending and increases band-to-band tunneling (BTBT) but also the high-work-function drain-side gate prevents ambipolar conduction by reinforcing the channel-drain barrier. Extensive 2D TCAD simulations with a non-local BTBT model show a great deal of improvement over the traditional single-metal HSM-NC-DGTFET. The proposed device is able to attain a 90% increase in ON-current, 42% decrease in threshold voltage, and a 38% decrease in subthreshold swing. Work-function modulation and optimized dielectric eliminate ambipolar leakage. Also, the device demonstrates greater analog/RF figures of merit, such as increased levels of transconductance (g_m), greater transconductance generation factor (TGF), higher cut-off frequency (f_T), and gain-bandwidth product (GBP). The synergistic combination of hetero-oxide engineering, dual metal work-function modulation and negative capacitance effect makes the HDM-NC-DGTFET a good candidate in next-generation low-power, high-frequency nanoelectronic applications.