Details

Autor(en) / Beteiligte

• Schmidt, Wolf Gero
• Wenzien, Bernd
• Bechstedt, Friedhelm

Titel

Coverage-dependent bonding of Sb on GaAs (110)

Ist Teil von

• Surface science, 1994-04, Vol.307, p.235-240

Ort / Verlag

Lausanne: Elsevier B.V

Erscheinungsjahr

1994

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• We performed total-energy Pseudopotential calculations for a variety of structures for Sb adsorbed on the GaAs (110) surface. Sb coverages of θ = 1 and θ = 1 2 are considered. For θ = 1 we investigate five earlier proposed structures and find the epitaxial continued layer structure (ECLS) to be the lowest one in energy. The epitaxial on top structure (EOTS) which fits better to recent STM images is slightly higher in energy. The electronic structure and the changes of the ionization energies for these models are also discussed in the context of experimental results and give further evidence for the ECLS. Its structural parameters are found to be in excellent agreement both with LEED and XSW data. For a coverage of θ = 1 2 we find two equivalent minima in the total-energy surface corresponding to long-bridge positions in the 1 × 1 surface unit cell. Studies of 1×2 and 2 × 1 reconstructions for this coverage are performed as well. Together with the energetical results for θ = 1 they indicate the tendency of Sb to form two-dimensional clusters for low coverages as observed experimentally.