Unipolar Schottky-Ohmic carbon nanotube field effect transistor

Abstract

A new structure for carbon nanotube field effect transistors (CNTFETs) is proposed and its current-voltage characteristic is simulated. The terminals of the transistor channel which is a single-wall carbon nanotube (CNT) are contacted to the metal electrodes and form different type of contacts at the interfaces. The carbon nanotube end which will form the source is contacted to the metal intrinsically and the other end of the CNT which forms the drain is doped with potassium and then contacted to the metal. We name this kind of CNTFET Schottky-Ohmic CNTFET (SO-CNTFET). The coaxial geometry SO-CNTFET has been considered for simulation. The proposed device is modeled using a semi-classical approach based on the assumption of ballistic transport through the channel. The SO-CNTFET exhibits unipolar characteristics and lower off current than conventional Schottky barrier CNTFETs (SB-CNTFETs). This paper adds the SO-CNTFEt to the library of different types of CNTFETs for future ULSI designs and applications.