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arXiv · 1206.5077

Modeling of a vertical tunneling graphene heterojunction field-effect transistor

S. Bala Kumar·Gyungseon Seol·Jing Guo
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Abstract

Vertical tunneling field-effect-transistor (FET) based on graphene heterojunctions with layers of hBN is simulated by self-consistent quantum transport simulations. It is found that the asymmetric p-type and n-type conduction is due to work function deference between the graphene contact and the tunneling channel material. Modulation of the bottom-graphene-contact plays an important role in determining the switching characteristic of the device. Due to the electrostatic short-channel-effects stemming from the vertical-FET structure, the output I-V characteristics do not saturate. The scaling behaviors the vertical-FET as a function of the gate insulator thickness and the thickness of the tunneling channel material are examined.

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S. Bala Kumar, Gyungseon Seol, Jing Guo. 2012-06-22. Modeling of a vertical tunneling graphene heterojunction field-effect transistor. https://doi.org/10.1063/1.4737394

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