Modeling of a Room-Temperature Silicon Quantum Dot-Based Single-Electron Transistor and the Effect of Energy-Level Broadening on Its Performance

Abstract

In this work, we have modeled silicon quantum dot (QD)-based single-electron transistors (SETs) operating at room temperature and investigated the effect of the QD’s energy-level broadening on the performance of the SET. First we obtained the energy levels and corresponding wave functions for spherical Si QDs by solving the coupled Schrodinger–Poisson equations in three dimensions. Then, we demonstrated different tunneling current rates for separated energy levels by considering nonequal energy-level broadenings. Accordingly, an expression for the corresponding tunneling rates in the quantum Coulomb blockade regime was derived. In the next step, the transconductance characteristics of the Si QD SET device with Coulomb oscillations were simulated, and their differences from previously investigated metal-based SETs were demonstrated. Finally, by applying different bias voltages, we determined the effect of temperature variations on the transconductance characteristics.