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arXiv · 1302.5318

Identification of a strong contamination source for graphene in vacuum systems

Christophe Caillier·Dong-Keun Ki·Yuliya Lisunova·Iaroslav Gaponenko·Patrycja Paruch·Alberto F. Morpurgo
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Abstract

To minimize parasitic doping effects caused by uncontrolled material adsorption, graphene is often investigated under vacuum. Here we report an entirely unexpected phenomenon occurring in vacuum systems, namely strong n-doping of graphene due to chemical species generated by common ion high-vacuum gauges. The effect --reversible upon exposing graphene to air-- is significant, as doping rates can largely exceed 10^{12} cm^{-2}/hour, depending on pressure and the relative position of the gauge and the graphene device. It is important to be aware of the phenomenon, as its basic manifestation can be mistakenly interpreted as vacuum-induced desorption of p-dopants.

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Christophe Caillier, Dong-Keun Ki, Yuliya Lisunova, Iaroslav Gaponenko, Patrycja Paruch, Alberto F. Morpurgo. 2013-11-08. Identification of a strong contamination source for graphene in vacuum systems. https://doi.org/10.1088/0957-4484%2F24%2F40%2F405201

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