Velocity Saturation effect on Low Frequency Noise in short channel Single Layer Graphene FETs

Abstract

Graphene devices for analog and RF applications are prone to Low Frequency Noise (LFN) due to its upconversion to undesired phase noise at higher frequencies. Such applications demand the use of short channel graphene transistors that operate at high electric fields in order to ensure a high speed. Electric field is inversely proportional to device length and proportional to channel potential so it gets maximized as the drain voltage increases and the transistor length shrinks. Under these conditions though, short channel effects like Velocity Saturation (VS) should be taken into account. Carrier number and mobility fluctuations have been proved to be the main sources that generate LFN in graphene devices. While their contribution to the bias dependence of LFN in long channels has been thoroughly investigated, the way in which VS phenomenon affects LFN in short channel devices under high drain voltage conditions has not been well understood. At low electric field operation, VS effect is negligible since carriers velocity is far away from being saturated. Under these conditions, LFN can be precicely predicted by a recently established physics-based analytical model. The present paper goes a step furher and proposes a new model which deals with the contribution of VS effect on LFN under high electric field conditions. The implemented model is validated with novel experimental data, published for the first time, from CVD grown back-gated single layer graphene transistors operating at gigahertz frequencies. The model accurately captures the reduction of LFN especially near charge neutrality point because of the effect of VS mechanism. Moreover, an analytical expression for the effect of contact resistance on LFN is derived. This contact resistance contribution is experimentally shown to be dominant at higher gate voltages and is accurately described by the proposed model.

arXiv commentMain Manuscript:10 pages, 6 figures

References in corpus (21)

• Electric Field Effect in Atomically Thin Carbon Films
• Detection of Individual Gas Molecules Absorbed on Graphene
• Graphene Photonics and Optoelectronics
• Graphene field effect transistors as room-temperature Terahertz detectors
• Review of the Low-Frequency 1/f Noise in Graphene Devices
• Mobility and Saturation Velocity in Graphene on SiO2
• Transport properties of graphene in the high-current limit
• Electrical and Noise Characteristics of Graphene Field-Effect Transistors: Ambient Effects and Noise Sources
• Graphene transistors for bioelectronics
• Direct Probing of 1/f Noise Origin with Graphene Multilayers: Surface vs. Volume
• Mobility-dependent Low-frequency Noise in Graphene Field Effect Transistors
• Effect of Spatial Charge Inhomogeneity on 1/f Noise Behavior in Graphene
• Role of Joule Heating on Current Saturation and Transient Behavior of Graphene Transistors
• Reduction of 1/f Noise in Graphene after Electron-Beam Irradiation
• Explicit drain current, charge and capacitance model of graphene field-effect transistors
• Graphene Thickness-Graded Transistors with Reduced Low-Frequency 1/f Noise
• Low-Frequency 1/f Noise in MoS2 Thin-Film Transistors: Comparison of Single and Multilayer Structures
• A physics based model of gate tunable metal-graphene contact resistance benchmarked against experimental data
• Large-Signal Model of Graphene Field-Effect Transistors -- Part I: Compact Modeling of GFET Intrinsic Capacitances
• Understanding the Bias Dependence of Low Frequency Noise in Sin-gle Layer Graphene FETs
• 1/f noise in graphene

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