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Embracing Uncertainty: Modeling the Standard Uncertainty in Electron Probe Microanalysis-Part I
1Microanalysis Group, Materials Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, MD20899-8371, USA.
Summary
A new framework for calculating standard uncertainty in electron excited X-ray microanalysis (EXM) measurements is introduced. This framework improves measurement accuracy and aids in optimizing experimental designs for EXM analysis.
Area of Science:
- Materials Science
- Analytical Chemistry
- Physics
Background:
- Electron excited X-ray microanalysis (EXM) is crucial for elemental analysis.
- Accurate uncertainty quantification in EXM is essential for reliable results.
- Current methods often overlook significant sources of error.
Purpose of the Study:
- To present a novel framework for computing standard uncertainty in EXM measurements.
- To address limitations in existing uncertainty models.
- To provide a foundation for more sophisticated EXM uncertainty analysis.
Main Methods:
- Development of a new computational framework for uncertainty.
- Application of the framework to simple subcomponents of EXM measurements.
- Identification of key factors influencing uncertainty, including surface roughness and coating thickness.
Main Results:
- A robust framework for calculating standard uncertainty in EXM.
- Inclusion of previously overlooked factors like surface roughness and coating thickness.
- Demonstration of the framework's applicability to basic EXM measurement scenarios.
Conclusions:
- The proposed framework offers a more comprehensive approach to EXM uncertainty.
- It enables more accurate error bar determination for EXM data.
- It serves as a basis for measurement optimization and expert system development in EXM.
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