Schottky-Barrier Carbon Nanotube Field Effect Transistor Modeling

Abstract

The theoretical performance of Carbon Nanotube Field Effect Transistors (CNFETs) with Schottky barriers is examined by means of a ballistic model. A novel approach is used to treat the Schottky barriers at the metal-nanotube contacts as mesoscopic scatterers. Evanescent-mode analysis is used to derive a length-scale and potential profile for the device. Noticeable current reduction is observed compared to previous ballistic models without Schottky barriers. The effects of device geometry, nanotube diameter and chirality as well as Schottky barrier height on the drain current are studied. Quantum conductance degradation due to Schottky barriers is also observed.