Adsorption geometry and saturation coverage of Na on the Si(100)-(2 times 1) surface: First-principles calculations

Journal Article · Tue Oct 15 04:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.44.8210· OSTI ID:5021386

Zhang, B L; Chan, C T; Ho, K M ^[1]

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1. Ames Laboratory and Department of Physics, Iowa State University, Ames, Iowa (USA)

We have performed first-principles total-energy calculations for Na on the Si(100)-(2{times}1) surface at different coverages. At half-monolayer Na coverage (one Na atom per Si(100)-(2{times}1) unit cell), the most favorable adsorption site of Na is found to be the valley bridge site. At one-monolayer Na coverage (two Na atoms per Si(100)-(2{times}1) unit cell), the Na atoms occupy both the valley bridge sites and the pedestal sites. The one-monolayer-coverage models have substantially lower surface energies than the half-monolayer-coverage models, indicating that the saturation coverage should be one monolayer. We also found that the surface is metallic at half-monolayer Na coverage and semiconducting at one-monolayer coverage.

• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 5021386
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 44:15; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

656000* -- Condensed Matter Physics
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ADSORPTION
ALKALI METALS
ELEMENTS
GEOMETRY
MATHEMATICS
METALS
SATURATION
SEMIMETALS
SILICON
SODIUM
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES