Graphene Field Effect Transistor

The SB-FET (Schottky-barrier field-effect transistor) is a field-effect transistor with metallic source and drain contact electrodes, which create Schottky barriers at both the source-channel and drain-channel interfaces. The GFET is a highly sensitive graphene-based field effect transistor. Graphene, because of its excellent mechanical, electrical, chemical, physical properties, sparked great interest to develop and extend its applications. Particularly, graphene based field‐effect transistors (GFETs) present exciting and bright prospects for sensing applications due to their greatly higher sensitivity and stronger selectivity. Graphene field-effect transistors (GFETs) take the typical FET device and insert a graphene channel tens of microns in size between the source and drain. Being graphene, a lattice of carbon atoms that is only one atom thick, the channels in GFETs have. Graphene field-effect transistors (GFETs) are emerging as bioanalytical sensors, in which their responsive electrical conductance is used to perform quantitative analyses of biologically-relevant molecules such as DNA, proteins, ions and small molecules.

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Abstract: The past decade has seen rapid growth in the research area of graphene andits application to novel electronics. With Moore's law beginning to plateau,the need for post-silicon technology in industry is becoming more apparent.Moreover, existing technology is insufficient for implementing terahertzdetectors and receivers, which are required for a number of applicationsincluding medical imaging and security scanning. Graphene is considered to be akey potential candidate for replacing silicon in existing CMOS technology aswell as realizing field effect transistors for terahertz detection, due to itsremarkable electronic properties, with observed electronic mobilities reachingup to $2 times 10^5$ cm$^2$ V$^{-1}$ s$^{-1}$ in suspended graphene samples.This report reviews the physics and electronic properties of graphene in thecontext of graphene transistor implementations. Common techniques used tosynthesize graphene, such as mechanical exfoliation, chemical vapor deposition,and epitaxial growth are reviewed and compared. One of the challengesassociated with realizing graphene transistors is that graphene issemimetallic, with a zero bandgap, which is troublesome in the context ofdigital electronics applications. Thus, the report also reviews different waysof opening a bandgap in graphene by using bilayer graphene and graphenenanoribbons. The basic operation of a conventional field effect transistor isexplained and key figures of merit used in the literature are extracted.Finally, a review of some examples of state-of-the-art graphene field effecttransistors is presented, with particular focus on monolayer graphene, bilayergraphene, and graphene nanoribbons.