3D TCAD modeling of NO2CNT FET sensors

A new approach for TCAD modeling of CNT FET gas sensors is presented, whose key feature is the use of an effective Gaussian DOS to mimic the 1D CNT DOS. The TCAD procedure has been applied to the simulation of a suspended CNT FET for NO₂ sensing. Our results indicate that the model is able to provide I- V characteristics in excellent agreement with the experimental data, both before and after gas exposure.

I. Introduction

Being all-surface objects exhibiting at the same time chemical, thermal and mechanical stability, carbon nanotubes (CNTs) are ideally suited to build highly sensitive, low-power and low-cost miniaturized gas sensors [1]. In [2] a device architecture based on a suspended CNT FET has been presented that offers the advantage of reduced power consumption, hysteresis-free operation and improved signal-to-noise ratio.