skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

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
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. 2016. "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 = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Save / Share:
  • The surface structure of thick (400 A) Gd(0001) films, epitaxially grown on W(110), is investigated by low-energy electron-diffraction (LEED) {ital IV} measurements in combination with dynamical LEED calculations. A first-layer contraction of 2.4% and a second-layer spacing expansion of 1% is found. These findings are in good agreement with literature values determined for the (0001) surface of bulk Gd crystals. No significant difference in the LEED {ital IV} data is found between films grown at room temperature and films grown at elevated temperatures.
  • The surface symmetry of cubic boron nitride (111) (c-BN) is characterized by low-electron energy diffraction. The polished c-BN (111) and hydrogen-plasma-treated sample both exhibit a 1{times}1 surface structure. The surface is effectively etched by hydrogen plasma. High-resolution Auger and electron-energy-loss spectroscopy studies confirmed that the hydrogen-etched surface retains the integrity of crystalline c-BN (111). Characteristic energy-loss peaks at 15 eV due to an interband transition and at 37 eV due to a bulk plasmon can be observed on the single-crystal surface, even though they are usually absent from the energy-loss spectra of pyrolytic or polycrystalline BN samples. {copyright} {ital 1997}more » {ital The American Physical Society}« less
  • Carbonaceous matter in peridotite xenoliths and basalt from the Hualalai Volcano, in a basalt glass collected directly from an active lava lake on the east rift of Kilauea, in garnet and diopside megacrysts from the Jagersfontein kimberlite, and in gabbros from the Stillwater and Bushveld Complexes has been studied by X-ray photoelectron spectroscopy (XPS), thermal-desorption surface analysis by laser ionization (SALI), and low-energy electron diffraction (LEED). The basalt and two of the four xenoliths from Hualalai and both Jagersfontein megacrysts yielded trace quantities ({le}10 nanomoles) of organic compounds on heating to 700C. Organics were not detected in the rocks frommore » the layered intrusions, and neither carbonaceous matter nor organics were detected in the glass from the lava lake. Where detected, organics appear to be associated with carbonaceous films on microcrack surfaces. Carbonaceous matter exists as films less than a few nm thick and particles up to 20 {mu}m across, both of which contain elements expected to be present in significant quantities in magmatic vapors, namely Si, alkalis, halogens, N, and transition metals. LEED studies suggest that the carbonaceous films are amorphous. The data suggest two possible mechanisms for the formation of the organics. One is that they are a product of abiotic heterogeneous catalysis of volcanic gas on new, chemically active mineral surfaces formed by fracturing during cooling. Alternatively, organics may have been assimilated into the volcanic gases prior to eruption and then deposited on cracks formed during eruption and cooling. In any case, there is no evidence to suggest that the organics represent laboratory or field biogenic contamination.« less
  • Previous low-energy electron-diffraction patterns show that the W(001) surface reconstructs at room temperature when exposed to hydrogen. Vibrational EELS data indicate that the tungsten atoms move together to form dimers which must be aligned in (10) directions to satisfy the symmetry requirement. The two possible dimer orientations define two orthogonal, degenerate domains. It has also been shown that steps on a surface may limit the growth of the reconstruction domains and may also influence the relative abundance of the domain orientations. The authors report here an extension of this previous work on step effects involving the relationship of step orientationmore » to domain growth and selection. Results obtained for three W(001) surfaces are compared. 7 references, 2 figures.« less