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Title: Dy uniform film morphologies on graphene studied with SPA-LEED and STM

Abstract

The use of graphene for microelectronics and spintronic applications requires strategies for metals to wet graphene and to grow layer-by-layer. This is especially important when metals will be used as electrical contacts or as spin filters. Extensive work in the literature so far has shown that this is very challenging, since practically all metals grow 3D, with multi-height islands forming easily. Reasons for the 3D morphology are the much weaker metal carbon bond when compared to the metal cohesive energy and the role of Coulomb repulsion of the poorly screened charges at the metal graphene interface. We employed the complementary techniques of SPA-LEED and STM to study the growth of Dy on graphene. It was found that under kinetic limitations it is possible to fully cover graphene with a bilayer Dy film, by growing well below room temperature in stepwise deposition experiments. Lastly, the Dy film, however, is amorphous but ways to crystallize it within the 2D morphology are possible, since long range order improves at higher growth temperature.

Authors:
 [1];  [1];  [1];  [1];  [2];  [1];  [1]
  1. Ames Lab. and Iowa State Univ., Ames, IA (United States)
  2. Univ. of Duisburg-Essen, Duisburg (Germany)
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1335039
Alternate Identifier(s):
OSTI ID: 1358880
Report Number(s):
IS-J-9090
Journal ID: ISSN 0008-6223; PII: S0008622316305383
Grant/Contract Number:
AC02-07CH11358; LPDS 2013-04
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Carbon
Additional Journal Information:
Journal Volume: 108; Journal Issue: C; Journal ID: ISSN 0008-6223
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

McDougall, D., Hattab, H., Hershberger, M. T., Hupalo, M., Horn von Hoegen, M., Thiel, P. A., and Tringides, M. C. Dy uniform film morphologies on graphene studied with SPA-LEED and STM. United States: N. p., 2016. Web. doi:10.1016/j.carbon.2016.06.083.
McDougall, D., Hattab, H., Hershberger, M. T., Hupalo, M., Horn von Hoegen, M., Thiel, P. A., & Tringides, M. C. Dy uniform film morphologies on graphene studied with SPA-LEED and STM. United States. doi:10.1016/j.carbon.2016.06.083.
McDougall, D., Hattab, H., Hershberger, M. T., Hupalo, M., Horn von Hoegen, M., Thiel, P. A., and Tringides, M. C. Fri . "Dy uniform film morphologies on graphene studied with SPA-LEED and STM". United States. doi:10.1016/j.carbon.2016.06.083. https://www.osti.gov/servlets/purl/1335039.
@article{osti_1335039,
title = {Dy uniform film morphologies on graphene studied with SPA-LEED and STM},
author = {McDougall, D. and Hattab, H. and Hershberger, M. T. and Hupalo, M. and Horn von Hoegen, M. and Thiel, P. A. and Tringides, M. C.},
abstractNote = {The use of graphene for microelectronics and spintronic applications requires strategies for metals to wet graphene and to grow layer-by-layer. This is especially important when metals will be used as electrical contacts or as spin filters. Extensive work in the literature so far has shown that this is very challenging, since practically all metals grow 3D, with multi-height islands forming easily. Reasons for the 3D morphology are the much weaker metal carbon bond when compared to the metal cohesive energy and the role of Coulomb repulsion of the poorly screened charges at the metal graphene interface. We employed the complementary techniques of SPA-LEED and STM to study the growth of Dy on graphene. It was found that under kinetic limitations it is possible to fully cover graphene with a bilayer Dy film, by growing well below room temperature in stepwise deposition experiments. Lastly, the Dy film, however, is amorphous but ways to crystallize it within the 2D morphology are possible, since long range order improves at higher growth temperature.},
doi = {10.1016/j.carbon.2016.06.083},
journal = {Carbon},
number = C,
volume = 108,
place = {United States},
year = {Fri Jul 01 00:00:00 EDT 2016},
month = {Fri Jul 01 00:00:00 EDT 2016}
}

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