Multiscale Modeling of Nanowire-based Schottky-Barrier Field-Effect Transistors for Sensor Applications

TL;DR

This paper introduces a multiscale theoretical framework combining electrostatics and quantum transport to model nanowire-based Schottky-barrier FETs, aiding sensor development.

Contribution

It develops a unified simulation platform integrating finite elements and Green's functions for realistic nanowire FET modeling.

Findings

Accurately reproduces I-V characteristics of nanowire FETs.

Shows good agreement with experimental data on device behavior.

Provides a versatile tool for designing nanowire sensors.

Abstract

We present a theoretical framework for the calculation of charge transport through nanowire-based Schottky-barrier field-effect transistors that is conceptually simple but still captures the relevant physical mechanisms of the transport process. Our approach combines two approaches on different length scales: (1) the finite elements method is used to model realistic device geometries and to calculate the electrostatic potential across the Schottky-barrier by solving the Poisson equation, and (2) the Landauer approach combined with the method of non-equilibrium Green's functions is employed to calculate the charge transport through the device. Our model correctly reproduces typical I-V characteristics of field-effect transistors and the dependence of the saturated drain current on the gate field and the device geometry are in good agreement with experiments. Our approach is suitable for one-dimensional Schottky-barrier field-effect transistors of arbitrary device geometry and it is intended to be a simulation platform for the development of nanowire-based sensors.