High-resolution structural analysis of the Sb-terminated GaAs(001)-(2{times}4) surface

Journal Article · Mon Jun 01 04:00:00 EDT 1998 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.57.R15056· OSTI ID:636176

Lee, T ^[1]; Bedzyk, M J ^[1]

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1. Department of Materials Science and Engineering and Materials Research Center, Northwestern University, Evanston, Illinois 60208 (United States)

The precise locations of Sb atoms for the GaAs(001):Sb-(2{times}4) surface were measured by the x-ray standing-wave (XSW) technique. The XSW results are consistent with symmetric Sb dimers, whose formation has recently been predicted by four competing models. The (004) and (022) XSW analysis determined the Sb dimer height and bond length to be 1.72 and 2.84 {Angstrom}, respectively. The Sb coverage of the (2{times}4) reconstruction was measured by Rutherford backscattering to be 0.48 monolayers. This coverage agrees with the two proposed structural models that have two Sb dimers per (2{times}4) unit cell and disagrees with the models that propose one or three Sb dimers. Finally, a (111) XSW measurement, which tested for lateral displacement of the Sb dimers in the [110] direction, was used to discriminate between the remaining two models. {copyright} {ital 1998} {ital The American Physical Society}

• Research Organization: Brookhaven National Laboratory
• DOE Contract Number: AC02-76CH00016; W-31109-ENG-38
• OSTI ID: 636176
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 24 Vol. 57; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANTIMONY
BOND LENGTHS
CRYSTAL STRUCTURE
GALLIUM ARSENIDES
STANDING WAVES
STRUCTURAL MODELS
SURFACES
X RADIATION