We present ab initio calculations of electron energy loss spectroscopy in the reflection geometry (REELS) for the Si(100) surface for which several experimental data are available. The standard surface models [p(2x1), c(4x2), and p(2x2)] are structurally very similar in nature, and precise calculations are necessary to differentiate between them. Starting from optimized geometries we compute REELS spectra within the framework of the three-layer model. We adopt several methodologies to ensure a realistic model of the experiment, including a precise partitioning of the surface and bulk dielectric functions and a numerical integration over the detector aperture. We obtain good agreement with the various available experimental energy loss and reflectance anisotropy spectra. The calculations allow us to definitively rule out the presence of the p(2x1) reconstruction. We interpret the S-0 peak observed by Farrell [Phys. Rev. B 30, 721 (1984)] in high resolution REELS. Furthermore, we explain the observed dependence of the spectra on temperature by inferring the presence of dimer flipping at room temperature.

Caramella, L., Hogan, C., Onida, G., DEL SOLE, R. (2009). High-resolution electron energy loss spectra of reconstructed Si(100) surfaces: first-principles study. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 79(15) [10.1103/PhysRevB.79.155447].

High-resolution electron energy loss spectra of reconstructed Si(100) surfaces: first-principles study

ONIDA, GIOVANNI;DEL SOLE, RODOLFO
2009-01-01

Abstract

We present ab initio calculations of electron energy loss spectroscopy in the reflection geometry (REELS) for the Si(100) surface for which several experimental data are available. The standard surface models [p(2x1), c(4x2), and p(2x2)] are structurally very similar in nature, and precise calculations are necessary to differentiate between them. Starting from optimized geometries we compute REELS spectra within the framework of the three-layer model. We adopt several methodologies to ensure a realistic model of the experiment, including a precise partitioning of the surface and bulk dielectric functions and a numerical integration over the detector aperture. We obtain good agreement with the various available experimental energy loss and reflectance anisotropy spectra. The calculations allow us to definitively rule out the presence of the p(2x1) reconstruction. We interpret the S-0 peak observed by Farrell [Phys. Rev. B 30, 721 (1984)] in high resolution REELS. Furthermore, we explain the observed dependence of the spectra on temperature by inferring the presence of dimer flipping at room temperature.
2009
Pubblicato
Rilevanza internazionale
Articolo
Sì, ma tipo non specificato
Settore FIS/03 - FISICA DELLA MATERIA
English
Con Impact Factor ISI
ab initio calculations; dielectric function; electron energy loss spectra; elemental semiconductors; geometry; reflectivity; silicon; surface reconstruction
http://link.aps.org/doi/10.1103/PhysRevB.79.155447
Caramella, L., Hogan, C., Onida, G., DEL SOLE, R. (2009). High-resolution electron energy loss spectra of reconstructed Si(100) surfaces: first-principles study. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 79(15) [10.1103/PhysRevB.79.155447].
Caramella, L; Hogan, C; Onida, G; DEL SOLE, R
Articolo su rivista
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/8043
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 8
social impact