Scaling Behaviors of Graphene Nanoribbon FETs: A Three Dimensional Quantum Simulation Study

Abstract

The scaling behaviors of graphene nanoribbon (GNR) Schottky barrier field-effect transistors (SBFETs) are studied by solving the non-equilibrium Green's function (NEGF) transport equation in an atomistic basis set self-consistently with a three-dimensional Poisson equation. The armchair edge GNR channel shares similarities with a zigzag CNT, but it has a different geometry and quantum confinement boundary condition in the transverse direction. The results indicate that the I-V characteristics are ambipolar and strongly depend on the GNR width because the bandgap of the GNR is approximately inversely proportional to its width, which agrees with recent experiments. A multiple gate geometry improves immunity to short channel effects, but it offers smaller improvement than it does for Si MOSFETs in terms of the on-current and transconductance. Reducing the oxide thickness is more useful for improving transistor performance than using a high-k gate insulator. Significant increase of the minimal leakage current is observed when the channel length is scaled below 10nm because the small effective mass facilitates strong source-drain tunneling. The GNRFET, therefore, does not promise extending the ultimate scaling limit of Si MOSFETs. The intrinsic switching speed of a GNR SBFET, however, is several times faster than that of Si MOSFETs, which could lead to promising high speed electronics applications, where the large leakage of GNR SBFETs is of less concern.

*These authors contributed equally to this work. 33 pages, 12 figures. The replacement of this manuscript is because a typo found in program which changes the quantitative results by factor of 2. The qualitative features and conclusions are not changed

References in corpus (3)

• Electric Field Effect in Atomically Thin Carbon Films
• Graphene Nano-Ribbon Electronics
• Room-temperature ballistic transport in narrow graphene strips

Cited by in corpus (10)

• Production, properties and potential of graphene
• Performance Comparison of Graphene Nanoribbon FETs with Schottky Contacts and Doped Reservoirs
• Computational Study of Tunneling Transistor Based on Graphene Nanoribbon
• Effect of Edge Roughness on Electronic Transport in Graphene Nanoribbon Channel Metal Oxide Semiconductor Field-Effect Transistors
• Modeling edge effects in Graphene Nanoribbon Field-effect Transistors with real and mode space methods
• An Ab Initio Study on Energy Gap of Bilayer Graphene Nanoribbons with Armchair Edges
• A current-voltage model for Schottky-barrier graphene based transistors
• Diluted chirality dependence in edge rough graphene nanoribbon field-effect transistors
• Field-Effect Transistor Based on MoSi${}_2$N${}_4$ and WSi${}_2$N${}_4$ Monolayers Under Biaxial Strain: A Computational Study of the Electronic Properties
• Mode space approach for tight-binding transport simulations in graphene nanoribbon field-effect transistors including phonon scattering