Get access
Advanced Materials

Angle-Scanned Photoelectron Diffraction: Probing crystalline ultrathin films

Authors

  • Prof. Gaetano Granozzi,

    Corresponding author
    1. Dipartimento di Chimica Inorganica, Metallorganica ed Analitica Centro CSSRCC del CNR. Università di Padova via Loredan 4. I–35131 Padova (Italy)
    • Dipartimento di Chimica Inorganica. Metallorganica ed Analitica Centro CSSRCC del CNR. University di Padova via Loredan 4. I–35131 Padova (Italy)
    Search for more papers by this author
    • Gaetano Granozzi is Full Professor of Inorganic Chemistry in the Department of Inorganic, Metallorganic and Analytical Chemistry of the University of Padova. He is currently the Director of the Research Unit of the Consortium INCM at te University of Padova. He is autor of over 150 papers in the following fields: Electronic structure of mono- and polynuclear inorganic and organometallic molecules by quantum mechanical calculations and spectroscopic measurements (1976–1988); Surface chemistry of materials and chemisorption studied by srface-sensitive spectroscopic measurements (since 1987); Thin film deposition and characterization (since 1989). His current main interests are in the growth mechanism and structure of ultrathin epitaxial films.

  • Dr. Mauro Sambi

    1. Dipartimento di Chimica Inorganica, Metallorganica ed Analitica Centro CSSRCC del CNR. Università di Padova via Loredan 4. I–35131 Padova (Italy)
    Search for more papers by this author

  • We thank Prof. C. S. Fadley (University of California, Davis and Lawrence Berkeley Laboratory) for critically reading the manuscript and for his many valuable comments and suggestions. We thank Prof. Ugo Bardi and Dr. Monica Galeotti (University of Firenze) for providing original data on the Co/Pt(111) system. Thanks are due also to the whole group of the Surface Science and Thin Film Laboratory of the University of Padova, and in particular to Prof. Eugenio Tondello for his encouragement in the implementation of the XPD technique

Abstract

Electrons emitted from the core levels of a photon-irradiated crystalline sample undergo scattering by atoms in the vicinity of the emitting species. Subsequent interference phenomena between the electron wave portions propagating to the detector produce intensity modulations as a function of the direction of detection. This process constitutes the physical basis of the angle-scanned X-ray photoelectron diffraction (XPD) technique. The resulting modulations, properly interpreted, are rich in structural information concerning the near-surface atomic layers. In this review, after an introduction to the principles of XPD, some selected results in the field of ultrathin epitaxial films will be reported in order to outline the merits of the technique. Qualitative structural information (e. g., growth modes and lattice distortions) is directly obtained from the experimental raw data without the need for theoretical simulation. On the other hand, quantitative structural parameters, as well as the presence of stacking faults and other structural defects, may be deduced by using a trial-and-error fitting procedure based on simple scattering models.

Get access to the full text of this article

Ancillary