A circuit model for defective bilayer graphene transistors

Abstract

a b s t r a c tThis paper investigates the behaviour of a defective single-gate bilayer graphene transistor. Point defects were introduced into pristine graphene crystal structure using a tightly focused helium ion beam. The transfer characteristics of the exposed transistors were measured ex-situ for different defect concentrations. The channel peak resistance increased with increasing defect concentration whilst the on-off ratio showed a decreasing trend for both electrons and holes. To understand the electrical behaviour of the transistors, a circuit model for bilayer graphene is developed which shows a very good agreement when validated against experimental data. The model allowed parameter extraction of bilayer transistor and can be implemented in circuit level simulators.

Defect Interaction and Deformation in Graphene

“…In reality, its surface is easily affected by deformation because of the material’s elasticity influence in the third dimension, which gives rise to strained structures such as ripples and bubbles. − In addition to physical deformation, the carbon atoms of graphene can also be removed, added, or rearranged during growth − and defects are introduced into the material. Recent experimental studies show that various defects can be introduced into graphene using focused electron beam irradiation. − These defects inevitably affect the physical properties of graphene. , …”