A Novel High Schottky Barrier Based Bilateral Gate and Assistant Gate Controlled Bidirectional Tunnel Field Effect Transistor

Xi Liu,Jong-Ho Lee,Xiaoshi Jin,Kailu Ma,Yicheng Wang,Meile Wu

doi:10.1109/jeds.2020.3020920

Abstract

In this article, we propose a high Schottky barrier source/drain contacts based bilateral gate and assistant Gate controlled bidirectional tunnel field Effect transistor (HSB-BTFET). Different from Schottky barrier (SB) MOSFET which use lower Schottky barrier to produces the thermionic emission current, the proposed HSB -BTFET utilizes higher Schottky barrier to minimize the thermionic emission current and adopts bilateral gate to generate a strong band-to-band tunneling (BTBT) current which works as the conduction mechanism of the forward current. An assistant gate is introduced which efficiently blocks the reverse biased leakage current. Compared to SB MOSFET, HSB-BTFET can realize lower subthreshold swing, much smaller leakage current, higher $\text{I}_{\mathrm{ on}}-{\mathrm{ I}}_{\mathrm{ off}}$ ratio, compared to TFET, it can realize larger forward current. Besides the device symmetry, it's more compatible with MOSFET technology. The function and influence of the Schottky barrier height have been analyzed.

Highlights

The research on the basic unit of integrated circuit focuses on two aspects
For the most ideal case, φBp is 0V, and the device can work as an ideal pn junction based p-type MOSFET which shows subthreshold swing (SS) (dlog(IDS)/dVGS) equals to 60mV/dec at room temperature [16], for a finite Schottky barrier height, the thermionic emission current is always smaller than in the ideal 0V barrier height case, thereafter, the SS of SB MOSFETs is often larger than 60mV/dec, the inability of subthermal SS through a Schottky barrier without considering others physical mechanisms such as band-to-band tunneling (BTBT) has been proved by a simple potential mapping method [17]
Take n type HSB-BTFET as an example, as Fig. 2(a) shows, if both the main gate and the assistant gate are forwardly biased, electron hole pairs generated by BTBT mainly in the source tunnel layer, the holes flow to the source contact, and the electrons in the conduction band flow to the drain contact due to that there is no barrier formed for electrons from source to drain

Summary

Introduction

The research on the basic unit of integrated circuit focuses on two aspects. One is to improve the integration, multi-gate FETs [1]–[2] is impressive in sub-30nm technology nodes. To realize larger forward current and smaller SS, the generation efficiency of BTBT should be increased as much as possible, that means the gate control ability should be strengthened and a sharp abrupt junction between the heavily doped region and intrinsic region should

Results

Conclusion