Dresden 2003 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
O: Oberflächenphysik
O 24: Postersitzung (Epitaxie und Wachstum, Oxide und Isolatoren, Elektronische Struktur, Oberfl
ächenreaktionen, Adsorption an Oberfl
ächen, Organische Dünnschichten)
O 24.18: Poster
Mittwoch, 26. März 2003, 14:30–17:30, P1
Electronic structure of Ni-Zn layers on Cu(111) — •Andreas Bayer, Christian Ammon, and Hans-Peter Steinrück — Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstr. 3, D-91058 Erlangen
Alternating evaporation of monolayers of Ni and Zn onto Cu(111) at low temperatures (100 K) leads to the formation of thin multilayer films with different properties as compared to the bimetallic Ni/Cu and Zn/Cu systems. The electronic structures of the films were studied by high resolution X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS) and temperature programmed desorption (TPD) of CO. The XP spectra clearly show that Ni on top of Zn layers results in a higher desorption temperature of Zn as compared to Zn terminated layers. After annealing the trimetallic systems to 600 K the binding energies of Zn 2p3/2, Ni 2p3/2 and Cu 2p3/2 are nearly identical, independent of the preparation procedure (Ni or Zn as first layer on Cu(111)). Furthermore the TPD spectra of CO adsorbed at 100 K are in both cases the same. This indicates that a surface alloy is formed with Zn partly desorbing and Ni partly segregating into the bulk.