Modeling and simulation of a dual-material asymmetric heterodielectric-gate TFET

Abstract

Analytical modeling of a dual-material asymmetric heterodielectric-gate tunnel field-effect transistor (FET) is carried out based on the Poisson equation and parabolic approximation techniques. An asymmetric gate with two materials having different work functions is used to eliminate the influence of the OFF-current (leakage current) and short-channel effects in the device. The lengths of metal 1 and metal 2 are taken to be 10 nm and 10 nm, respectively, and the device performance is analyzed. Expressions for the surface potential, electric field, and drain current are obtained by using a two-dimensional (2D) mathematical model, whose results are compared with those obtained using the Silvaco technology computer-aided design (TCAD) simulator, revealing good agreement. The proposed dual-material asymmetric gate tunnel FET produces an improved ON-current of 10−5 A/µm and a decreased OFF current of 10−10 A/µm, with an ON/OFF ratio of 105.