Method for the calculation of the chemical composition of a thin film by Monte Carlo simulation and electron probe microanalysis

Abstract

Based on a simplified Monte Carlo simulation model of electron scattering and characteristic x-ray excitation of a multicomponent film on a substrate, a calculation method with an iteration approach was developed to transform the x-ray intensity ratios measured by an electron probe microanalyzer into the chemical composition of the thin film on the substrate. The calculation of the characteristic fluorescence is also included in the simulation. The calculation results of compositions for several specimens agree well with measured data. individually: J D 14.0 1 exp 0.1Z C 75.5 Z z/7.5 Z 100 C Z Z 19 J D 9.76 C 58.8Z 1.19 Z 20 J D 13.5Z 21 J D 11.5Z 22 J D [9.0 1 C Z 2/3 C 0.03Z]Z 23 J D 12.4 C 0.027Z Z 24

Characterization of the Chemical Composition of Uranium Microparticles with Irregular Shapes Using Standardless Electron Probe Microanalysis and Micro-Raman Spectrometry

“…MC simulations have also been proven to be viable to deal with complex analysis in nonconventional samples such as microparticles 8 and thin films. 10 In MC codes, the interactions of electrons and photons with matter are described by a set of differential cross-sections (DCSs) that characterize the probability distribution of each interaction mechanism. Nevertheless, even the most accurate and widely used approaches for cross-section determination are based on approximations, which may lead to important uncertainties.…”

“…Numerous works have shown promising results when the calculation of X-ray intensities is performed by Monte Carlo (MC) simulations. − It is presumed that by including instrument characteristics as well as the morphological and physical–chemical properties of samples, rigorous corrections can be obtained. MC simulations have also been proven to be viable to deal with complex analysis in nonconventional samples such as microparticles and thin films …”

Monte Carlo Simulation of Characteristic Secondary Fluorescence in Electron Probe Microanalysis of Homogeneous Samples Using the Splitting Technique

“…Despite there exist many approaches available for the assessment of fluorescence enhancement (Reed, 1965; Ugarte et al, 1987), it is impossible to compare these predictions with experimental data as the photons produced by fluoresced atoms cannot be discriminated from the total recorded radiation. Therefore, Monte Carlo simulations constitute a very important tool for estimating the fluorescence enhancement and a number of specific situations have been faced with this approach (Fisher, 1971; Hu & Pan, 2001; Llovet & Galan, 2003; Fournelle et al, 2005; Fournelle, 2007).…”

Separate K-line contributions to fluorescence enhancement in electron probe microanalysis

“…In the present work, the contribution to F due to the Kβ line in binary samples is considered according to Reed's approach [4], and certain cases of special interest are shown, in which the omission or the improper assessment of this contribution leads to inaccurate quantification results. These cases are for example when Kβ is the only K line capable of producing fluorescence excitement [5], and when the need to determine trace elements [6,7] makes this contribution absolutely necessary to improve the quantification accuracy.…”