Graphene field-effect transistors

Abstract

Owing in part to scaling challenges for metal oxide semiconductor field-effect transistors (MOSFETs) and complementary metal oxide semiconductor (CMOS) logic, the semiconductor industry is placing an increased emphasis on emerging materials and devices that may provide improved MOSFET performance beyond the 22 nm node, or provide novel functionality for, e.g. ‘beyond CMOS’ devices. Graphene, with its novel and electron–hole symmetric band structure and its high carrier mobilities and thermal velocities, is one such material that has garnered a great deal of interest for both purposes. Single and few layer carbon sheets have been fabricated by a variety of techniques including mechanical exfoliation and chemical vapour deposition, and field-effect transistors have been demonstrated with room-temperature mobilities as high as 10 000 cm2 V−1 s−1. But graphene is a gapless semiconductor and gate control of current is challenging, off-state leakage currents are high, and current does not readily saturate with drain voltage. However, various ways to overcome, adapt to, or even embrace this property are now being considered for device applications. In this work we explore through illustrative examples the potential of and challenges to graphene use for conventional and novel device applications.

Nanomaterials in transistors: From high-performance to thin-film applications

“…Extensive articles reviewing the distinctive properties of each of these nanomaterials have been published (8)(9)(10)(11)(12)(13)(14)(15); as the focus of this Review is on the use of the nanomaterials in transistors, only a brief summary of their key attributes is given. Of note is that single-walled CNTs and graphene share the sp 2 -bonded, hexagonal carbon lattice and thus exhibit similar carrier transport properties, including high Fermi velocity (v F ), which can lead to higher switching speeds.…”

DFT study on the interaction between atomic aluminum and graphene

“…2 On the other hand, it has been proposed that, considering its chemical a±nity against certain molecules, the incorporation of a particular heteroatom to the graphene lattice would make it a very speci¯c sensor for gases, for example, by testing the ohmic response of doped graphene as well as measuring the characteristic current-voltage curves of a FET with this material in the gate. 10,11 In the speci¯c case of an Al heteroatom, several theoretical works have been reported concerning to the adsorption of diatomic (CO, NO, O 2 , H 2 ), 12-15 triatomic (NO 2 , SO 2 , CO 2 , H 2 O) 13,14 and larger molecules (NH 3 , H 2 CO). 13,14,16 It should be underlined that in all the inherent calculations with Al and other heteroatoms, only the PBE functional for exchange and correlation was employed.…”

Field-Effect Phototransistors Based on Graphene-Quantum Dot Hybrids

“…The photoconductive gain of FEpTs based on graphene-QD hybrids has reached up to 10 8 and was several orders of magnitude larger that of any graphene FETs or QD FETs reported before [2][3][4][5]. The excellent performance of extra high mobility and responsivity of FEpTs based on graphene-quantum dots is mainly attributed to the large absorbance of PbSe QDs and the fast transport in graphene [6].…”