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Updated: May 12, 2026
07:24
Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Note: Alignment/focus dependent core-line sensitivity for quantitative chemical analysis in hard x-ray photoelectron
Conan Weiland1, Raymond Browning, Barry A Karlin
1Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
The Review of Scientific Instruments
|April 6, 2013
Summary
Quantitative chemical analysis using X-ray photoelectron spectroscopy (XPS) can be inaccurate. Focus and alignment affect peak intensities in position imaging mode, but not in angular imaging mode, which is essential for reliable XPS analysis.
Area of Science:
- Surface Science
- Analytical Chemistry
- Spectroscopy
Background:
- X-ray photoelectron spectroscopy (XPS) is a key surface-sensitive analytical technique.
- Accurate quantitative chemical analysis via XPS relies on precise peak intensity measurements.
- Previous studies have not fully addressed focus and alignment effects on XPS peak intensities.
Purpose of the Study:
- To investigate the impact of focus and alignment on relative peak intensities in XPS.
- To compare the performance of position imaging mode versus angular imaging mode for quantitative XPS.
- To determine the optimal mode for reliable quantitative chemical analysis using XPS.
Main Methods:
- Utilized X-ray photoelectron spectroscopy (XPS) with a hemispherical electron analyzer.
- Operated the analyzer in both position imaging mode and angular imaging mode.
- Analyzed relative peak intensities of silver (Ag) 2p₃/₂ and Ag 3d peaks in an Ag specimen.
Main Results:
- Observed a significant focus and alignment dependence of relative peak intensities in position imaging mode.
- Documented a decrease of over 50% in the Ag 2p₃/₂ to Ag 3d ratio under varying focus/alignment conditions.
- Found no focus/alignment dependence when employing the angular imaging mode.
Conclusions:
- The focus and alignment of the electron analyzer critically influence quantitative XPS results in position imaging mode.
- Angular imaging mode provides robust and reliable quantitative chemical analysis by eliminating focus/alignment artifacts.
- For accurate quantitative chemical analysis, XPS should be performed using angular imaging mode.
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