Ionization Depth Distribution in EPMA : Improvement of the Random Walk Model

G. CASTELLANO; S. SEGUI; J. TRINCAVELLI

X-RAY SPECTROMETRY

J. Wiley & Sons

Año: 1998 vol. 27 p. 293 - 298

0049-8246

A model for the parameter c involved in Packwood and BrownÏs expression for the ionization depth distribution Phi(rhoz) in EPMA is developed. Assuming that the electrons perform a random walk within the sample, the parameter gamma 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 gamma values produce a very good description of Phi(rhoz) distributions obtained through Monte Carlo simulations and experimental data.