Structure analysis of Si(111)-( radical 3 times radical 3 ) R 30 degree /Ag using x-ray standing waves

Journal Article · Fri Mar 15 04:00:00 EST 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.7185· OSTI ID:5853768

Vlieg, E; Fontes, E; Patel, J R ^[1]

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1. AT T Bell Laboratories, Murray Hill, New Jersey 07974 (US)

The x-ray standing-wave technique has been used to determine the positions of the Ag atoms in the Si(111)-({radical}3 {times} {radical}3 ){ital R}30{degree}/Ag reconstruction. Using the (111) reflection, the Ag atoms are found to be located in one plane at a height of 3.44{plus minus}0.02 A above the center of the extrapolated bulk Si(111) bilayer. This rules out several models that have been previously proposed in the literature for the reconstructed surface. Data obtained by using the (11{bar 1}) and (220) reflections show that the Ag atoms are reconstructed, i.e., are laterally displaced away from bulk Si positions. This directly rules out the Ag-honeycomb model. Taking into account the many other studies on this system, the most favored arrangement of the Ag atoms is in the form of triangles, with three Ag atoms per unit cell. The registry of this Ag triangle with respect to the substrate has also been determined.

• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5853768
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 43:9; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
COHERENT SCATTERING
CRYSTAL STRUCTURE
DIFFRACTION
ELEMENTS
LAYERS
METALS
SCATTERING
SEMIMETALS
SILICON
SILVER
STANDING WAVES
STRUCTURAL MODELS
TRANSITION ELEMENTS
X-RAY DIFFRACTION