AMaSiS 2021 - Abstract

Nastasi, Giovanni

Simulation of graphene field effect transistors

Coauthor: Vittorio Romano
Università degli Studi di Catania, Italy

Metal Oxide Semiconductor Field Effect Transistor (MOSFET) is the backbone of the modern integrated circuits. In the case the active area is made of traditional semiconductor materials such as, for example, silicon or gallium arsenide, a lot of analysis and simulations have been performed in order to optimize the design.
Lately, a great attention has been devoted to graphene [1] on account of its peculiar features and, in particular, from the point of view of nano-electronics, for the high electrical conductivity. It is highly tempting to try to replace the traditional semiconductors with graphene in the active area of electron devices like the MOSFETs (cfr.[2,3,4,5]).
Here, graphene field effect transistors, where the active area is made of monolayer large-area graphene, are simulated including a full 2D Poisson equation and a drift-diffusion model with mobilities deduced by a direct numerical solution of the semiclassical Boltzmann equations for charge transport by a suitable discontinuous Galerkin approach (cfr. [6,7,8]).
The critical issue in a graphene field effect transistor is the difficulty of fixing the off state which requires an accurate calibration of the gate voltages. We propose and simulate a graphene field effect transistor structure which has well-behaved characteristic curves similar to those of conventional (with gap) semiconductor materials. The introduced device has a clear off region and can be the prototype of devices suited for post-silicon nanoscale electron technology. We compare numerical results with the simulation of standard GFET structures.

Acknowledgments: The authors acknowledge the financial support from Università degli Studi di Catania, Piano della Ricerca 2020/2022 Linea di intervento 2/“QICT”. G. N. acknowledges the financial support from the National Group of Mathematical Physics (GNFM-INdAM) it Progetti Giovani GNFM 2020.

References
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