Unexpected scaling of the performance of carbon nanotube Schottky-barrier transistors

Abstract

We show that carbon nanotube Schottky-barrier transistors exhibit scaling that is qualitatively different than conventional transistors. The performance depends in an unexpected way on both the thickness and the dielectric constant of the gate oxide. Experimental measurements and theoretical calculations for ambipolar devices provide a consistent understanding of the novel scaling, which reflects the very different device physics of a Schottky-barrier transistor with a quasi-one-dimensional channel contacting a sharp edge. A simple analytic model gives explicit scaling expressions for key device parameters such as subthreshold slope, turn-on voltage, and transconductance. © 2003 The American Physical Society.