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arXiv · 1608.05023

Field effect in stacked van der Waals heterostructures: Stacking sequence matters

Daniele Stradi·Nick R. Papior·Mads Brandbyge
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Abstract

Stacked van der Waals (vdW) heterostructures where semi-conducting two-dimensional (2D) materials are contacted by overlayed graphene electrodes enable atomically-thin, flexible electronics. We use first-principles quantum transport simulations of graphene-contacted MoS2 devices to show how the transistor effect critically depends on the stacking configuration relative to the gate electrode. We can trace this behavior to the stacking-dependent response of the contact region to the capacitive electric field induced by the gate. The contact resistance is a central parameter and our observation establish an important design rule for devices based on 2D atomic crystals.

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Daniele Stradi, Nick R. Papior, Mads Brandbyge. 2016-08-17. Field effect in stacked van der Waals heterostructures: Stacking sequence matters. https://doi.org/10.1021/acs.nanolett.7b00473

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