The hydrogenated and bare diamond (110) surface: a combined LEED-, XPS-, and ARPES study

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Details zur Publikation

Autor(en): Hammer L, Ristein J, Ley L
Zeitschrift: Surface Science
Verlag: Elsevier
Jahr der Veröffentlichung: 1999
Band: 443
Seitenbereich: 177
ISSN: 0039-6028


Abstract

The atomic and electronic structures of the hydrogenated and hydrogen-free diamond (110) surface are investigated by low-energy electron diffraction (LEED), angle-resolved photoelectron spectroscopy (ARPES), and X-ray induced core-level spectroscopy (XPS). From the C 1s core-level spectra, different states of surface termination can be distinguished. The plasma-hydrogenated surface exhibits a surface C 1s component shifted by 0.8 eV towards a higher binding energy, which we attribute to coadsorbed hydrocarbons. During thermal annealing up to 900 °C, gradual desorption first of the hydrocarbons and then of hydrogen yields a clean surface with a surface C 1s component shifted by -1.1 eV and an increase in downward band bending of about 1.2 eV compared to the as-prepared surface. From the valence band spectra, we conclude that an essentially hydrogen-terminated surface is maintained at an annealing temperature of 600-800 °C. All states of the surface are unreconstructed. After the plasma treatment, the surface reveals monoatomic steps running parallel to the [11̄0] direction. From an analysis of the extinction of LEED reflexes, we conclude that within the chains of surface atoms running along [11̄0], the C-C bond length is uniformly altered in a way that keeps the chains undimerized. Finally, for the hydrogen-free surface, an occupied surface band is observed with a dispersion of 0.35 eV between Γ̄ and J̄ that lies entirely below the valence band maximum.


FAU-Autoren / FAU-Herausgeber

Hammer, Lutz Dr.
Lehrstuhl für Festkörperphysik
Ley, Lothar Prof. Dr.
Naturwissenschaftliche Fakultät
Ristein, Jürgen apl. Prof. Dr.
Lehrstuhl für Laserphysik

Zuletzt aktualisiert 2018-09-08 um 05:38