Thickness characterization of atomically thin WSe2 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

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


In this work, low-energy electron microscopy is employed to probe structural as well as electronic information in few-layer WSe2 on epitaxial graphene on SiC. The emergence of unoccupied states in the WSe2-graphene heterostructures is studied using spectroscopic low-energy electron reflectivity. Reflectivity minima corresponding to specific WSe2 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 WSe2 electron reflectivity. This method allows for unambiguous counting of WSe2 layers, and furthermore may be applied to other two-dimensional transition metal dichalcogenide materials.

Original languageEnglish (US)
Article number04J106
JournalJournal of Vacuum Science and Technology B: Nanotechnology and Microelectronics
Issue number4
StatePublished - Jul 1 2016

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Instrumentation
  • Process Chemistry and Technology
  • Surfaces, Coatings and Films
  • Electrical and Electronic Engineering
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Thickness characterization of atomically thin WSe<sub>2</sub> on epitaxial graphene by low-energy electron reflectivity oscillations'. Together they form a unique fingerprint.

Cite this