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arXiv · 1402.0734

Impact of graphene polycrystallinity on the performance of graphene field-effect transistors

David Jiménez·Aron W. Cummings·Ferney Chaves·Dinh Van Tuan·Jani Kotakoski·Stephan Roche
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Abstract

We have used a multi-scale physics-based model to predict how the grain size and different grain boundary morphologies of polycrystalline graphene will impact the performance metrics of graphene field-effect transistors. We show that polycrystallinity has a negative impact on the transconductance, which translates to a severe degradation of the maximum and cutoff frequencies. On the other hand, polycrystallinity has a positive impact on current saturation, and a negligible effect on the intrinsic gain. These results reveal the complex role played by graphene grain boundaries, and can be used to guide the further development and optimization of graphene-based electronic devices.

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David Jiménez, Aron W. Cummings, Ferney Chaves, Dinh Van Tuan, Jani Kotakoski, Stephan Roche. 2014-02-04. Impact of graphene polycrystallinity on the performance of graphene field-effect transistors. https://doi.org/10.1063/1.4863842

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