Charge-related problems associated with X-ray microanalysis in the variable pressure scanning electron microscope at...

Area of Science:

• Materials Science
• Analytical Chemistry
• Physics

Background:

• Variable pressure scanning electron microscopy (VPSEM) is a powerful technique for analyzing nonconductive samples.
• However, charging effects in VPSEM can significantly complicate X-ray data interpretation.
• Understanding these charging effects is crucial for accurate material analysis.

Purpose of the Study:

• To review approaches for mitigating charging effects in VPSEM.
• To present data illustrating the impact of charging on X-ray emissions.
• To provide guidance for obtaining reliable X-ray data from nonconductive samples.

Main Methods:

• Review of documented methods for charge mitigation in VPSEM.
• Experimental data collection under various VPSEM operating conditions.
• Analysis of X-ray emissions influenced by sample charging and chamber gas pressure.

Main Results:

• Charging effects in VPSEM can significantly alter detected X-ray signals.
• Higher specimen chamber gas pressures are often necessary for reliable X-ray data.
• Sample composition strongly influences local charging and primary electron landing energy.

Conclusions:

• Careful consideration of operating conditions is essential for interpreting VPSEM X-ray data from nonconductive materials.
• Optimizing gas pressure and understanding sample-specific charging behaviors are key to accurate analysis.
• This work highlights the importance of managing charging artifacts for robust VPSEM investigations.