Comparison of the I–V characteristics of a topological insulator quantum well resonant tunneling transistor and its conventional counterpart: A TCAD simulation study

Abstract

In this study, we investigated and simulated the structure of a quantum well resonant tunneling (QWRT) transistor based on two barriers and a well in the middle. The barriers were formed of semiconductors with a higher bandgap and the well separating the barriers comprised a semimetal-like material with a very small bandgap, i.e., close to zero. The device was positioned on the oxide to exploit the benefits of SOI technology, e.g., improving leakage and the immunity of the device against environment effects. When the well thickness was a few nanometers, the electron-bound states appeared in the quantum well region. By tuning the voltage and work function of the top gate, the bound states moved in the potential well and the carriers were transferred through the well via the resonant tunneling phenomenon. Our simulations showed the step-like behavior of the output characteristics and the oscillatory quantum switching of the transfer characteristics for the proposed device. We also investigated the influence of the well thickness and gate voltage on the device characteristics, and we compared the optimal case with a theoretical analysis of a QWRT transistor based on a topological insulator.