Atomic structure and thermal stability of two-dimensional Er silicide on Si(111)

Journal Article · Mon Jul 01 04:00:00 EDT 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.54.2004· OSTI ID:286370

Lohmeier, M; Huisman, W J; ter Horst, G; Zagwijn, P M; Vlieg, E ^[1]; Nicklin, C L ^[2]; Turner, T S ^[3]

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1. FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam (The Netherlands)
2. Condensed Matter Physics Group, Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)
3. Daresbury Rutherford Appleton Laboratories, Warrington WA4 4AD (United Kingdom)

The atomic structure of Er silicides on Si(111) in the submonolayer range has been studied by means of medium-energy ion scattering and surface x-ray diffraction. We find good agreement between the two techniques. The ion-scattering measurements indicate that the Er adsorbs in a single two-dimensional layer on top of which a completely relaxed (bulklike) Si bilayer is located. This bilayer is exclusively of {ital B} type, i.e., rotated by 180{degree} with respect to the substrate bilayers. The x-ray diffraction results show that Er is positioned on {ital T}{sub 4} sites only, i.e., above second-layer substrate atoms. For low coverages (0.23 ML), the height of the top bilayer appears to be reduced by approximately 0.4 A. We attribute this to the fact that the Er does not form a closed layer, leading to the formation of less ordered Er-Si complexes in which extra Si adatoms provide the backbonds for the Si hexagons on top of the Er. Finally, we investigate the thermal stability of the two-dimensional silicide, and find that the two-dimensional Er layer evolves into relaxed three-dimensional islands at temperatures above 800{degree}C with concomitant strain relaxation. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 286370
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 3 Vol. 54; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ANNEALING
CHEMISORPTION
CRYSTAL STRUCTURE
ELECTRON DIFFRACTION
EPITAXY
ERBIUM SILICIDES
HYDROGEN IONS
ION SCATTERING ANALYSIS
KEV RANGE 10-100
SILICON
SORPTIVE PROPERTIES
STRESS RELAXATION
SYNCHROTRON RADIATION
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
X-RAY DIFFRACTION