Simulation and optimization of HEMTs

TL;DR

This paper presents a comprehensive simulation system for nanoscale HEMTs using self-consistent Poisson-Schrödinger solutions, incorporating mobility dependence, and proposes a graded channel design to enhance device performance.

Contribution

The paper introduces a detailed simulation framework for HEMTs that accurately models quantum and electrostatic effects and suggests a novel graded channel design for performance improvement.

Findings

Simulation results match experimental measurements.

Inclusion of mobility dependence improves accuracy.

Graded channel design enhances transconductance.

Abstract

We have developed a simulation system for nanoscale high-electron mobility transistors, in which the self-consistent solution of Poisson and Schr\"odinger equations is obtained with the finite element method. We solve the exact set of nonlinear differential equations to obtain electron wave function, electric potential distribution, electron density, Fermi surface energy and current density distribution in the whole body of the device. For more precision, local dependence of carrier mobility on the electric field distribution is considered. We furthermore compare the simulation to a recent experimental measurement and observe perfect agreement. We also propose a graded channel design to improve the transconductance and thereby the threshold frequency of the device.