Elemental analysis by high-energy electron excitation

摘要

The possibility of using high-energy beta-particles (10(2)-10(3) keV) to induce the emission of characteristic x-rays from pure chemical elements, with important improvements with respect to conventional excitation methods, has been recently reviewed. An excitation procedure named BIXE (beta-induced x-ray emission) is used for implementing a spectrometric technique along the lines developed for EPMA (electron probe microanalysis). We have found that by using BIXE it is possible to determine binary sample compositions of elements present at concentrations higher than 1%, by comparisons with reference samples to obtain calibration curves. Experience with EPMA shows that when ternary and higher order samples are analyzed, the use of reference samples is not enough and it is necessary to perform theoretical corrections to the relationship between the line intensity and the corresponding concentrations, as a suitable complement to the analytical procedure. Semi-quantitative results are thus obtained with corrections applied through the ZAF method usually used in EPMA. In this work we concentrated in finding whether calibration curves as used in EPMA (where the electron beam is monochromatic) can be used in BIXE, where the electron beam is polychromatic (the beta spectrum).We expect that BIXE can be developed as a spectrometric technique whose main advantages are that it is a low-cost technique suitable for in situ studies and that the experimental arrangement and data acquisition and its evaluation are comparatively simple. Copyright (C) 2004 John Wiley Sons, Ltd.