Title
High Layer Uniformity of Two-Dimensional Materials Demonstrated Surprisingly from Broad Features in Surface Electron Diffraction
Publication Date
9-9-2020
Department
Chemistry; Materials Science and Engineering; Ames Laboratory; Physics and Astronomy
Campus Units
Chemistry, Materials Science and Engineering, Physics and Astronomy, Ames Laboratory
OSTI ID+
1709117
Report Number
IS-J 10311
DOI
10.1021/acs.jpclett.0c02113
Journal Title
The Journal of Physical Chemistry Letters
Volume Number
11
Issue Number
21
First Page
8937
Last Page
8943
Abstract
Paradoxically, a very broad diffraction background, named the bell-shaped-component (BSC), has been established as a feature of graphene growth. Recent diffraction studies as a function of electron energy have shown that the BSC is not related to scattering interference. Here, additional experiments are carried out as a function of temperature over the range in which single-layer graphene (SLG) grows. Quantitative fitting of the profiles shows that the BSC follows the increase of the Gr(10) spot, proving directly that the BSC indicates high-quality graphene. Additional metal deposition experiments provide more information about the BSC. The BSC is insensitive to metal deposition, and it increases with metal intercalation, because a more uniform interface forms between graphene and SiC. These experiments support the conclusion that the BSC originates from electron confinement within SLG, and surprisingly, it is an excellent measure of graphene uniformity.
DOE Contract Number(s)
AC02-07CH11358
Language
en
Department of Energy Subject Categories
36 MATERIALS SCIENCE
Publisher
Iowa State University Digital Repository, Ames IA (United States)