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arXiv · 1606.04167

Thickness characterization of atomically-thin WSe$_2$ on epitaxial graphene by low-energy electron reflectivity oscillations

Sergio C. de la Barrera·Yu-Chuan Lin·Sarah M. Eichfeld·Joshua A. Robinson·Qin Gao·Michael Widom·Randall M. Feenstra
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Abstract

In this work, low-energy electron microscopy is employed to probe structural as well as electronic information in few-layer WSe$_2$ on epitaxial graphene on SiC. The emergence of unoccupied states in the WSe$_2$--graphene heterostructures are studied using spectroscopic low-energy electron reflectivity. Reflectivity minima corresponding to specific WSe$_2$ states that are localized between the monolayers of each vertical heterostructure are shown to reveal the number of layers for each point on the surface. A theory for the origin of these states is developed and utilized to explain the experimentally observed featured in the WSe$_2$ electron reflectivity.

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Sergio C. de la Barrera, Yu-Chuan Lin, Sarah M. Eichfeld, Joshua A. Robinson, Qin Gao, Michael Widom, Randall M. Feenstra. 2016-06-13. Thickness characterization of atomically-thin WSe$_2$ on epitaxial graphene by low-energy electron reflectivity oscillations. https://doi.org/10.1116/1.4954642

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