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Inelastic Mean Free Path Data for Si Corrected for Surface Excitation

Published online by Cambridge University Press:  15 November 2005

Gábor Tamás Orosz
Affiliation:
Research Institute for Technical Physics and Materials Sciences, P.O. Box 49, H-1525 Budapest, Hungary
György Gergely
Affiliation:
Research Institute for Technical Physics and Materials Sciences, P.O. Box 49, H-1525 Budapest, Hungary
Sándor Gurbán
Affiliation:
Research Institute for Technical Physics and Materials Sciences, P.O. Box 49, H-1525 Budapest, Hungary
Miklós Menyhard
Affiliation:
Research Institute for Technical Physics and Materials Sciences, P.O. Box 49, H-1525 Budapest, Hungary
Aleksander Jablonski
Affiliation:
Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Kasprzaka 44/52, Poland
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Abstract

Surface-sensitive electron spectroscopies, like Auger electron spectroscopy, X-ray photoelectron spectroscopy and elastic peak electron spectroscopy (EPES) are suitable techniques to investigate surfaces and thin layers. A theoretical model for electron transport is needed to process the observed electron spectra. Electron transport descriptions are based on the differential elastic cross sections for the sample atoms and the inelastic mean free path (IMFP) of backscattered electrons. An electron impinging on the sample can lose energy either due to surface or volume excitations. In the present work a Monte Carlo (MC) simulation of the elastic peak of Si, Ag, Ni, Cu, and Au for surface analysis is presented. The IMFP of Si was determined applying the EPES method. The integrated elastic peak ratio of Si with the standard metal reference samples corrected for surface excitation provided IMFP values of Si in the energy range E = 0.2–2.0 keV. Experiments were made with the ESA 31 HSA (ATOMKI) and with the DESA-100 (Staib) spectrometers. Surface correction was based on the application of Chen's model and material parameters. The Monte Carlo simulations of elastically backscattered electron trajectories were made using new EPESWIN software of Jablonski. An improvement of IMFP experimental results was achieved applying the presented procedure.

Type
Papers from the European Microbeam Analysis Society Regional Workshop in Bled, Slovenia
Copyright
© 2005 Microscopy Society of America

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References

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