A Novel Comb-Gate-Overlap-Source Tunnel Field-Effect Transistor Based on the Electric Field Fringe Effect

Abstract

In this article, a novel comb-gate-overlap-source TFET (CGOS-TFET) is designed and fabricated. The device combines surface tunneling with the electric field fringe effect to improve the tunneling probability. Compared with TFET devices fabricated with the same process parameters, the CGOS-TFET devices can improve the On-state current of the device by more than 31 times. Moreover the subthreshold swing of the device is reduced by more than 61%, and the turn-on voltage of the device is reduced by about half. The electric field fringe effect improves the surface tunneling probability of the tunneling region but also introduces nonideal effects, such as the hot carrier effect when the voltage is large. This article briefly analyzes the On-state current deterioration caused by the hot carrier effect and the ambipolar effect in the devices. The study is important to improve the characteristics of TFET devices, which have a good guiding role in accelerating the progress of device applications.