Effects of the Gate Dielectric on the Subthreshold Transport of Carbon Nanotube Network Transistors Grown by Using Plasma-enhanced Chemical Vapor Deposition

Abstract

In this study, we investigated the subthreshold slope of random network carbon nanotube transisters with different geometries and passivations. Single-wall carbon nanotubes with lengths of 1-2 in were grown by using plasma-enhanced chemical vapor deposition to form the transistor channels. A critical channel length, where the subthreshold slope was saturated. of 7 pm was obtained. This was due to the percolational behavior of the nanotube random networks. With the dielectric passivation, the subthreshold slope was dramatically reduced from 9 V/decade to 0.9 V/decade by reducing interfacial trap sites, which then reduced the interface capacitance between the nanotube network and the gate dielectric.