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Metal-on-Metal Heteroepitaxy and the Influence of a Surfactant: Cu/O/Ru(0001)

  • H. Wolter
  • M. Schmidt
  • M. Nohlen
  • K. Wandelt

Abstract

Cu-on-Ru(OOOl) has been a suitable model system for metal-on-metal heteroepitaxy for many years because of the immiscibility of the two components. In contrast to most ex-situ studies the present work emphasizes dynamical work function change (ΔØ) measurements using a special KELVIN-capacitor probe as being a sensitive method to monitor the film morphology in-situ , that is during film growth. In particular, it is demonstrated that preadsorbed oxygen on the Ru(0001) substrate permanently “floats out” to the Cu surface and acts as a surfactant for layer-by- layer growth at a temperature of 400 K, at which in the absence of oxygen non-ergodic growth leads to the formation of pyramidal clusters and, hence, a very rough film. The mechanistic influence of the surfactant oxygen is discussed in detail and may certainly be carried over to other metal-on-metal systems.

Keywords

Work Function Thin Metal Film Step Atom Work Function Change Rough Film 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • H. Wolter
    • 1
  • M. Schmidt
    • 1
  • M. Nohlen
    • 1
  • K. Wandelt
    • 1
  1. 1.Institut für Physikalische und Theoretische ChemieUniversität BonnBonnGermany

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