Publikations Einzelansicht

Titel: EPMA Sputter Depth Profiling, Part I: Theory and Evaluation
 

Autor(en):
 
S. Richter, N. Lesch und P. Karduck
 
Journal: Mikrochim. Acta
Jahr: 1998
Band: 15
Seite(n): 125-131


Zusammenfassung:
Electron probe x-ray microanalysis is capable of the sensitive detection and the reliable quantification of small (partial)mass coverages on a submicron scale. To improve depth profiling so as to give reasonable depth resolution, the technique can be combined with a sputtering process. This paper presents theoretical aspects concerning the experiment of EPMA sputter depth profiling and the evaluation of the measured data. By means of a Monte-Carlo-Simulation program sputter-intensity profiles for multilayered systems can be calculated. It is shown that the calculated intensity-sputter profiles provide more information about elemental depth distributions than those obtained by the more common EPMA-method of electron beam energy variation.<br> For optimising the new technique, its sensitivity to the measuring parameters and the material’s composition and structure is studied. As a result, at low electron beam energies the calculated profiles of intensity versus sputtered depth correspond approximately to the elemental-depth profiles. At relatively high energies the sensitivity is reduced but, due to the characteristic features in the intensity profiles such as kinks at sharp interfaces, there is sufficient information (although convoluted by the excitation volume) for structure determination.<br> For reconstructing elemental-depth distributions from intensity-sputter profiles an algorithm based on maximum entropy analysis is developed. The algorithm is tested using calculated x-ray data from a well-characterised multilayer structure and the data are overlaid by statistical noise. Then elemental-depth profiles can be determined quantitatively with regard to both composition and depth coordinate.

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Publikations Einzelansicht

Titel: EPMA Sputter Depth Profiling, Part I: Theory and Evaluation
 

Autor(en):
 
S. Richter, N. Lesch und P. Karduck
 
Journal: Mikrochim. Acta
Jahr: 1998
Band: 15
Seite(n): 125-131


Zusammenfassung:
Electron probe x-ray microanalysis is capable of the sensitive detection and the reliable quantification of small (partial)mass coverages on a submicron scale. To improve depth profiling so as to give reasonable depth resolution, the technique can be combined with a sputtering process. This paper presents theoretical aspects concerning the experiment of EPMA sputter depth profiling and the evaluation of the measured data. By means of a Monte-Carlo-Simulation program sputter-intensity profiles for multilayered systems can be calculated. It is shown that the calculated intensity-sputter profiles provide more information about elemental depth distributions than those obtained by the more common EPMA-method of electron beam energy variation.<br> For optimising the new technique, its sensitivity to the measuring parameters and the material’s composition and structure is studied. As a result, at low electron beam energies the calculated profiles of intensity versus sputtered depth correspond approximately to the elemental-depth profiles. At relatively high energies the sensitivity is reduced but, due to the characteristic features in the intensity profiles such as kinks at sharp interfaces, there is sufficient information (although convoluted by the excitation volume) for structure determination.<br> For reconstructing elemental-depth distributions from intensity-sputter profiles an algorithm based on maximum entropy analysis is developed. The algorithm is tested using calculated x-ray data from a well-characterised multilayer structure and the data are overlaid by statistical noise. Then elemental-depth profiles can be determined quantitatively with regard to both composition and depth coordinate.

Zurück zur Listen Ansicht