A Three-Dimensional Simulation Study of the Performance of Carbon Nanotube Field-Effect Transistors with Doped Reservoirs and Realistic Geometry

Gianluca Fiori, IEEE
Giuseppe Iannaccone, IEEE
Gerhard Klimeck, Network for Computational Nanotechnology and Purdue University

Abstract

This paper simulates the expected device performance and scaling perspectives of carbon nanotube (CNT) fieldeffect transistors with doped source and drain extensions. The simulations are based on the self-consistent solution of the threedimensional Poisson–Schrödinger equation with open boundary conditions, within the nonequilibrium Green’s function formalism, where arbitrary gate geometry and device architecture can be considered. The investigation of short channel effects for different gate configurations and geometry parameters shows that doublegate devices offer quasi-ideal subthreshold slope and draininduced barrier lowering without extremely thin gate dielectrics. Exploration of devices with parallel CNTs shows that ON currents per unit width can be significantly larger than the silicon counterpart, while high-frequency performance is very promising.