Elastic Scattering Corrections in AES and XPS. III. Behaviour of Electron Transport Mean Free Path in Solids for Kinetic Energies in the Range 100 eV<E<400 eV

In the gas phase, the Ioffe–Regel criterion that electron transport becomes modified when the mean free path equals the electron wavelength (L = λ) applies clearly only to helium and hydrogen, which have a net repulsive interaction with electrons. The Mott criterion, that when L = λ/2π the electron is in a localized state, also applies to these two gases. The two criteria are less effective for molecules that have net attractive interactions with the electrons, because the interactions are not simply additive. They are not useful for xenon gas. The criteria are also assessed for: (a) several highly polarizable, spherical and nonspherical molecules; (b) polar molecules; (c) nitrogen and carbon dioxide, which form transient anions.

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Determination of the inelastic mean free path of electrons in silver and copper by measurement and calculation of the elastic scattering coefficient

Surface Science ◽

10.1016/0039-6028(88)90538-9 ◽

1988 ◽

Vol 200 (2-3) ◽

pp. 361-367 ◽

Cited By ~ 45

Author(s):

W. Doliński ◽

S. Mróz ◽

M. Zagórski

Keyword(s):

Elastic Scattering ◽

Free Path ◽

Mean Free Path ◽

Scattering Coefficient ◽

Inelastic Mean Free Path

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Inelastic Mean Free Path Data for Si Corrected for Surface Excitation

Microscopy and Microanalysis ◽

10.1017/s1431927605050713 ◽

2005 ◽

Vol 11 (6) ◽

pp. 581-585

Author(s):

Gábor Tamás Orosz ◽

György Gergely ◽

Sándor Gurbán ◽

Miklós Menyhard ◽

Aleksander Jablonski

Keyword(s):

Monte Carlo ◽

Electron Transport ◽

Free Path ◽

Photoelectron Spectroscopy ◽

Electron Spectroscopy ◽

Mean Free Path ◽

Thin Layers ◽

Elastic Peak ◽

Surface Excitation ◽

Inelastic Mean Free Path

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.

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