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arXiv · 2010.08404

Tuning the doping of epitaxial graphene on a conventional semiconductor via substrate surface reconstruction

Miriam Galbiati·Luca Persichetti·Paola Gori·Olivia Pulci·Marco Bianchi·Luciana Di Gaspare·Jerry Tersoff·Camilla Coletti·Philip Hofmann·Monica De Seta·Luca Camilli
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Abstract

Combining scanning tunneling microscopy and angle-resolved photoemission spectroscopy, we demonstrate how to tune the doping of epitaxial graphene from p to n by exploiting the structural changes that occur spontaneously on the Ge surface upon thermal annealing. Furthermore, using first principle calculations we build a model that successfully reproduces the experimental observations. Since the ability to modify graphene electronic properties is of fundamental importance when it comes to applications, our results provide an important contribution towards the integration of graphene with conventional semiconductors.

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Miriam Galbiati, Luca Persichetti, Paola Gori, Olivia Pulci, Marco Bianchi, Luciana Di Gaspare, Jerry Tersoff, Camilla Coletti, Philip Hofmann, Monica De Seta, Luca Camilli. 2020-10-16. Tuning the doping of epitaxial graphene on a conventional semiconductor via substrate surface reconstruction. https://doi.org/10.1021/acs.jpclett.0c03649

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