AVS 47th International Symposium
    Material Characterization Tuesday Sessions
       Session MC-TuA

Paper MC-TuA8
Intercomparison of IMFPs Determined by Elastic Peak Electron Spectroscopy

Tuesday, October 3, 2000, 4:20 pm, Room 207

Session: Quantitative Surface Analysis
Presenter: S. Tougaard, University of Southern Denmark
Authors: S. Tougaard, University of Southern Denmark
M. Krawczyk, Polish Academy of Sciences
A. Jablonski, Polish Academy of Sciences
J. Pavluch, Dept. Electronics and Vacuum Physics, Czech Rep.
J. Toth, Hungarian Academy of Sciences
D. Varga, Hungarian Academy of Sciences
G. Gergerly, Hungarian Academy of Sciences
M. Menyhard, Hungarian Academy of Sciences
A. Sulyok, Hungarian Academy of Sciences
Correspondent: Click to Email
We have evaluated the consistency and accuracy of IMFPs determined from comparison of the intensity of elastically reflected electrons with theoretical calculations. The scatter in determined IMFPs with experimental geometry, spectrometer energy resolution and the procedure for background subtraction was determined. Four spectrometers with widely different geometries and energy resolutions, placed in four different laboratories in three countries were used. Four background subtraction methods (Shirley, linear, Tougaard, and ELPSEP) were applied to isolate the elastic peak intensity from the reflected electron spectra. The RMS deviation of the IMFP from a function fitted to the data is 3.01 - 4.11 A depending on the background subtraction method and it is smallest for the Tougaard method. The RMS deviation from IMFP values calculated by Tanuma et al is 3.41 - 4.41 A again with the smallest value for the Tougaard method. The mean percentage deviation from the Tanuma et al values is ~ 18 %. The results point to the conclusion that the major contribution to the inaccuracies in IMFPs determined with the elastic peak method is not the background subtraction procedure but rather lack of accuracy of the presently available models for elastic electron scattering, i.e. atomic elastic scattering cross sections and effects of crystallinity that are not included in the presently applied models. @FootnoteText@ @footnote@ Work supported by EU contract INCO COPERNICUS ERBIC15CT960800.