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Standardless EDS analysis of bulk and thin specimens
1Structure Research Laboratory, University of Science and Technology of China, Anhui.
Journal of Electron Microscopy Technique
|December 1, 1987
Summary
A revised electron scattering model establishes a direct link between x-ray intensity and concentration ratios. This improves quantitative standardless energy-dispersive X-ray spectroscopy (EDS) analysis for bulk and thin samples.
Area of Science:
- Materials Science
- Analytical Chemistry
- Physics
Background:
- Quantitative analysis using electron microscopy relies on accurate elemental composition determination.
- Standardless energy-dispersive X-ray spectroscopy (EDS) methods require precise calculation of elemental sensitivity factors.
- Existing methods for calculating these factors can be limited in accuracy, especially for complex samples.
Purpose of the Study:
- To establish a direct relationship between x-ray intensity ratios and concentration ratios for bulk and thin specimens.
- To determine accurate ionization cross sections for improved quantitative standardless EDS analysis.
- To validate a revised full-diffusion model for electron scattering in quantitative elemental analysis.
Main Methods:
- Development and application of a revised full-diffusion model of electron scattering.
- Comparison of experimental x-ray intensity ratios (I(L)/I(K) and I(M)/I(L)) with calculated values for various elements.
- Quantitative standardless EDS analysis of bulk and thin film samples.
Main Results:
- A direct relationship between x-ray intensity ratio and concentration ratio was established.
- Suitable ionization cross sections were determined, significantly improving accuracy.
- The revised method provides more satisfactory quantitative standardless EDS analysis for bulk samples compared to commercial indirect methods.
- Quantitative standardless analysis of thin samples showed significant improvement.
Conclusions:
- The revised full-diffusion model and determined ionization cross sections enhance the accuracy of quantitative standardless EDS analysis.
- This direct method offers a more reliable approach for elemental analysis of bulk and thin film materials.
- The method is applicable to diverse sample types, including films on substrates with or without common elements.
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