Performance Assessment of GaSb-Si Vertical TFET with Triple Metal Gate for Low Power Application

This chapter represents the simulation study of a GaSb-Si triple metal gate vertical tunnel field-effect transistor (TMG-VTFET). The TMG-VTFET has distinct work function which is analysed using technology CAD (TCAD) in this chapter. In this proposed device structure, the metal gate is segregated into three regions. In this study, we have obtained better switching characteristics of TMG-VTFET by using a narrow bandgap material in the source region and improved electrostatic control on the channel because of triple metal gate. It exhibits an Ion of 1.75×10−4Aμm, an Ioff of 8.835×10−19Aμm, an IonIoff ratio of 1.9×1014, and subthreshold slope (SS) of 22.1 mVdec at VDS=0.5V. The heterojunction gate dielectric assists in upgrading the properties (ON current and OFF current) of the proposed device. There are three distinct metal work functions used in the channel junction that generates potential difference in the channel junction, thereby decreasing the current flowing through the drain. In this work, ambipolarity is being controlled by the structure of triple metal gate. We have also explored the influence of metal work functions and gate oxide on the proposed device characteristics. The simulation results demonstrate that the proposed TMG-vertical TFET exhibits low power consumption and fast switching characteristics, making it a promising candidate for digital applications.