Screening and interlayer coupling in multilayer graphene field-effect transistors

TL;DR

This paper presents a systematic experimental study and modeling of charge distribution, interlayer coupling, and noise reduction in multilayer graphene transistors, revealing thickness-dependent performance characteristics without altering graphene's band structure.

Contribution

It introduces a resistor network model incorporating screening and interlayer coupling to explain experimental results in multilayer graphene transistors, without modifying the band structure.

Findings

Thickness dependence of Ion, Ioff, and Ion/Ioff ratio

Experimental demonstration of noise reduction in few-layer graphene transistors

Model explains charge distribution without changing graphene's band structure

Abstract

With the motivation of improving the performance and reliability of aggressively scaled nano-patterned graphene field-effect transistors, we present the first systematic experimental study on charge and current distribution in multilayer graphene field-effect transistors. We find a very particular thickness dependence for Ion, Ioff, and the Ion/Ioff ratio, and propose a resistor network model including screening and interlayer coupling to explain the experimental findings. In particular, our model does not invoke modification of the linear energy-band structure of graphene for the multilayer case. Noise reduction in nano-scale few-layer graphene transistors is experimentally demonstrated and can be understood within this model as well.