Schottky Barrier Carbon Nanotube Field Effect Transistor: Electronic Characterizations

For the equilibrium condition, the carrier concentrations in valence and conduction band of the proposed carbon nanotube field effect transistor were found by allowing the local electrostatic potential to rigidly shift the one dimension density of states. Results suggest that the Maxwell-Boltzman approximation can be used as a good estimation for determining the carbon nanotube charge for the mid band of the nanotube for low gate voltages at equilibrium. The electrostatics of CNFETs was explored by self-consistently solving the Poisson equation in one dimension with the equilibrium carrier concentration. The CNFET I-V characteristic is estimated by applying voltage to the source/drain contacts and considering the triangle shape for Schottky barriers. The result confirms the evolution of the drain characteristics and it can be seen that ballistic CNFETs show similar I-V characteristics to the ballistic MOSFETs. The drain current saturation displayed in the output characteristics occurs when the drain bias is large similar to the same situation in ballistic MOSFET