Ionization depth-distribution in EPMA: improvement of the random walk model

G. CASTELLANO; S. SEGUI; J. TRINCAVELLI

X-RAY SPECTROMETRY

Wiley

Lugar: Amberes, Bélgica; Año: 1998 vol. 27 p. 293 - 298

0049-8246

<!-- @page { size: 8.5in 11in; margin: 0.79in } P { margin-bottom: 0.08in } --> A model for the parameter γ involved in Packwood and Brown's expression for the ionization depth-distribution ϕ(ρz) in EPMA is developed. Assuming that the electrons perform a random walk within the sample, the parameter γ is related to the probability of finding an electron in the surface layer after a large number of steps. Despite the simplicity of the model, the resulting γ values produce a very good description of ϕ(ρz) distributions obtained through Monte Carlo simulations and experimental data.