Regensburg 2004 – scientific programme

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DS: Dünne Schichten

DS 8: Dünnschichtanalytik I

DS 8.1: Invited Talk

Monday, March 8, 2004, 14:30–15:15, HS 32

Electron holography — •Hannes Lichte — Institut fuer Strukturphysik, TU Dresden, 01062 Dresden

Today, the performance of transmission electron microscopy (TEM) is well developed to a resolution limit of close to 0.1nm; in particular since the recently successful correction of spherical aberration of electron lenses, the interpretability of electron images allows quantitative analysis of most interesting structures, e.g. at defects and interfaces. Nevertheless, a conventional electron microscope is still a poor phase contrast microscope, i.e. it is virtually blind for pure phase structures such as electric or magnetic fields. Electron holography has overcome this blindness: by superposition of a reference wave on the object wave, a hologram is produced, from which the phase structure of the object wave can quantitatively be determined. This allows access to electric and magnetic fields, from mesoscopic to atomic dimensions, as well as the determination of atom species in compound specimen. Recent applications in the field of nanomagnetics, dopant profiling in semiconductors, and in ferroelectrics show the state of the art and the limits of the holographic method.