Role of Quasi-Fermi potential in modeling III-V TFETs: InAs as a case study

Abstract

TFET accurate physically based models are highly required to analyze and predict the device character- istics for its future utilization in circuits. In order to precisely model TFETs, it is essential to understand the several aspects related to the physics-based modeling of these devices. Using 2D TCAD simulation, we showed that in order to appropriately model the electrostatic potential in InAs-based TFETs, the electron quasi-Fermi potential (eQFP) should be taken to depend on biasing conditions, both VDS and VGS, contrary to the case of Si-based TFETs in which the eQFP is considered independent of VGS which is widely encoun- tered in the literature. The study is carried out for InAs double-gate homojunction tunnel FETs (DG- TFETs). In addition, we applied the main key factor of dependence of eQFP on a modified TFET model and it is revealed that the interpretation of eQFP correctly predicts the electrostatic potential and the drain-to-source band to band tunneling current. 2022 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Ain Shams Uni- versity. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/ by-nc-nd/4.0/).