Dresden 2003 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

DS: Dünne Schichten

DS 1: FV-internes Symposium „Dünnschichtanalytik“ I

DS 1.5: Hauptvortrag

Montag, 24. März 2003, 12:10–12:50, GER/37

A Sharp Eye on Thin Films - Advances Through Synchrotron Radiation — •Ralf Röhlsberger — Physikdepartment, Technische Universität München, James-Franck-Str. 1, 85747 Garching

The enormous brilliance of modern synchrotron radiation sources has opened unique avenues for the study of thin films. X-ray reflection in grazing incidence geometry allows one to determine density profiles of buried layers with very high spatial resolution. Applications include the structure refinement of organic films, the characterization of ultrathin oxide layers on metal surfaces and atomic layering of liquids in contact with boundaries. From the analysis of diffuse (small-angle) scattering and (wide-angle) surface diffraction one obtains information about the lateral ordering within stratified media. X-ray interference effects like the excitation of waveguide modes allow for a selective enhancement of the radiation intensity inside single layers. A further increase of the selectivity is achieved by tuning the energy of the radiation to an absorption edge. Due to the elemental specifity one is able to obtain layer-resolved information about the layer system, which is applied in many areas of thin-film magnetism, for example. A recent application is the determination of magnetization density profiles with very high spatial resolution. Another promising scattering technique is nuclear resonant scattering of synchrotron radiation which is the time-based analogue of classical Mössbauer spectroscopy. In this field the use of isotopic probe layers in combination with x-ray standing-wave techniques allows one to study the internal magnetic structure of thin films with atomic resolution.