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.
@article{arxiv.2106.14712,
title = {Electric-field-driven conductance switching in encapsulated graphene nanogaps},
author = {E. Pyurbeeva and J. L. Swett and Q. Ye and O. W. Kennedy and J. A. Mol},
journal= {arXiv preprint arXiv:2106.14712},
year = {2021}
}