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arXiv · 1202.2905

Molecular beam growth of graphene nanocrystals on dielectric substrates

Ulrich Wurstbauer·Theanne Schiros·Cherno Jaye·Annette S. Plaut·Rui He·Albert Rigosi·Christopher Gutiérrez·Daniel Fischer·Loren N. Pfeiffer·Abhay N. Pasupathy·Aron Pinczuk·Jorge M. García
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Abstract

We demonstrate the growth of graphene nanocrystals by molecular beam methods that employ a solid carbon source, and that can be used on a diverse class of large area dielectric substrates. Characterization by Raman and Near Edge X-ray Absorption Fine Structure spectroscopies reveal a sp2 hybridized hexagonal carbon lattice in the nanocrystals. Lower growth rates favor the formation of higher quality, larger size multi-layer graphene crystallites on all investigated substrates. The surface morphology is determined by the roughness of the underlying substrate and graphitic monolayer steps are observed by ambient scanning tunneling microscopy.

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Ulrich Wurstbauer, Theanne Schiros, Cherno Jaye, Annette S. Plaut, Rui He, Albert Rigosi, Christopher Gutiérrez, Daniel Fischer, Loren N. Pfeiffer, Abhay N. Pasupathy, Aron Pinczuk, Jorge M. García. 2012-02-14. Molecular beam growth of graphene nanocrystals on dielectric substrates. https://doi.org/10.1016/j.carbon.2012.06.008

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