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arXiv · 2106.14712

Electric-field-driven conductance switching in encapsulated graphene nanogaps

E. Pyurbeeva·J. L. Swett·Q. Ye·O. W. Kennedy·J. A. Mol
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Abstract

Feedback-controlled electric breakdown of graphene in air or vacuum is a well-established way of fabricating tunnel junctions, nanogaps, and quantum dots. We show that the method is equally applicable to encapsulated graphene constrictions fabricated using hydrogen silsesquioxane. The silica-like layer left by hydrogen silsesquioxane resist after electron-beam exposure remains intact after electric breakdown of the graphene. We explore the conductance switching behavior that is common in graphene nanostructures fabricated via feedback-controlled breakdown, and show that it can be attributed to atomic-scale fluctuations of graphene below the encapsulating layer. Our findings open up new ways of fabricating encapsulated room-temperature single-electron nanodevices and shed light on the underlying physical mechanism of conductance switching in these graphene nanodevices.

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E. Pyurbeeva, J. L. Swett, Q. Ye, O. W. Kennedy, J. A. Mol. 2021-06-28. Electric-field-driven conductance switching in encapsulated graphene nanogaps. https://doi.org/10.1063/5.0061630

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