AVS 53rd International Symposium
    Exhibitor Workshop Tuesday Sessions
       Session EW-TuL

Paper EW-TuL4
Next Generation Commercial LEEM FE-LEEM P90

Tuesday, November 14, 2006, 1:20 pm, Room Exhibit Hall

Session: Exhibitor Workshop
Presenter: A. Berghaus, SPECS GmbH, Germany
Authors: B. Achilles, SPECS GmbH, Germany
A. Berghaus, SPECS GmbH, Germany
Correspondent: Click to Email
A next generation Low Energy Electron Microscope (FE-LEEM P90) with unsurpassed 5 nm resolution for dynamic LEEM experiments is available from SPECS GmbH, Berlin. With this instrument, based on the design of Dr. Rudolf Tromp, nanometer scale processes on surfaces can be made visible in real-time. At this year's AVS Fall Meeting an innovative energy filter for PEEM imaging will be presented, which enables imaging with an energy resolution down to 250meV with a minimal impact on the high spatial resolution of the instrument. Low Energy Electron Microscopy, invented by E. Bauer, is a key technique for research in the field of surface dynamical processes, growth and structure. In a LEEM electrons are slowed down to energies of not more than several ten eV before they interact with the sample. Therefore the information only comes from the very surface of the sample. This allows in situ observation and analysis of surface processes. Guiding the design of the SPECS FE-LEEM P90 was the goal to achieve the highest resolution with a minimum number of electron-optical elements. Incoming and outgoing electrons are separated by a 90° magnetic prism array. This geometry allows a simple, intuitive step by step adjustment of all lens parameters. The magnetic prism transfers both the LEEM image and the LEED pattern astigmatically, allowing routine switching between real image and diffraction pattern. Both image and LEED pattern are transferred without the negative effects of chromatic dispersion, offering superior image and diffraction capabilities. The SPECS FE-LEEM P90 is integrated into a UHV LEEM sample analysis chamber with facilities for sample preparation and in-situ high temperature sample processing.