IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Applied Surface Analysis Tuesday Sessions
       Session AS-TuM

Paper AS-TuM3
The Combination of a Laboratory X-ray Source with an Energy Filtered Bolt-on PEEM Optics: An Innovative Approach Towards Micro-XPS Instrumentation of the Future

Tuesday, October 30, 2001, 9:00 am, Room 134

Session: High Spatial Resolution and Imaging
Presenter: M. Merkel, FOCUS GmbH, Germany
Authors: M. Merkel, FOCUS GmbH, Germany
M. Escher, FOCUS GmbH, Germany
Th. Kammler, FOCUS GmbH, Germany
J. Settemeyer, FOCUS GmbH, Germany
D. Funnemann, OMICRON GmbH, Germany
B. Gottschlich, OMICRON GmbH, Germany
M. Klais, Johannes Gutenberg Universität, Germany
A. Oelsner, Johannes Gutenberg Universität, Germany
Ch. Ziethen, Johannes Gutenberg Universität, Germany
G. Schönhense, Johannes Gutenberg Universität, Germany
Correspondent: Click to Email
Due to remarkable advances in micro and nano technology, the need for microscopically resolved spectroscopic information continues to increase. The photoemission electron microscope (PEEM) is capable of delivering, laterally, high-resolution images together with detailed spectroscopic information.@footnote 1@ In combination with laboratory excitation sources in the VUV and X-ray range, it offers a very simple method for chemically analysing sample surfaces. To this end, dispersive filters (e.g. of the hemispherical type) are already being used successfully.@footnote 2@ The use of a retarding field analyser combined with a PEEM is an innovative and versatile attempt to obtain microspectra and/or energy filtered images. We describe the instrumentation and we present results obtained with a bolt-on, state-of-the-art PEEM, combined with a modular imaging, high pass energy filter of the RFA type. The excitation is accomplished using a common monochromatised laboratory bolt-on X-ray source. With this equipment, it is possible to obtain XPS-spectra from sample regions smaller than 1µm with an electron energy range up to more than 1000 eV wide.@footnote 3@ Despite the fact that the PEEM acts as a low-pass filter, one could acquire spectra up to the Fermi cut-off without difficulty. The low intensity of high-energy photoelectrons arising from a low excitation source intensity is crucial for tuning the PEEM optics to the desired kinetic energy. The optimal, electron optical parameters typically deviate strongly from those applying to the threshold regime of the PEEM. We offer a means to optimise the optics regardless of the available intensity of the excitation source. @FootnoteText@ @footnote 1@ H. Ade (Ed.), 'Spectromicroscopy', J. Electron Spectrosc. Relat. Phenom. 84 (1997) @footnote 2@ E. Bauer, J. Electron Spectrosc. Relat. Phenom. 114 -116 (2001) 975-987 . @footnote 3@ M.Merkel et al., Surface Science, to be published.