SEM Electron Microprobe Analyzer

What is electron microprobe analysis?

Electron microprobe analysis is the quantitative detection of the electron-bombardment-induced emission of characteristic X-rays. This allows for the rapid, nondestructive determination of the chemical composition of regions smaller than 1 µm in a planar, well-polished sample that is stable under high vacuum (elements B to U for the JXA-8530F).

The JEOL JXA-8530F electron microprobe is an electron microscope that has a nominal imaging resolution of 3 nm with six spectrometers for non-destructive X-ray microanalysis and imaging of solid samples up to 10 cm in size.

The Schottky field-emission electron gun yields probe diameters that are only 1/5 to 1/10 the size of those produced in conventional electron microprobe instruments with tungsten filament or LaB₆ tips, allowing for sub-micron analytical spatial resolution. Even at low acceleration and large currents, small probe diameters are obtained that allow high X-ray spatial resolution.

The instrument has 5 wavelength-dispersive spectrometers (WDS) that permit the measurement of elements from B through U, and is set up for conventional microanalysis as well as trace-element analysis. In addition, this instrument is equipped with an energy-dispersive spectrometer, which is capable of X-ray count rates in excess of 200k cps and has high-speed X-ray mapping and quantitative microanalytical capabilities that rival the WDS. It is also equipped with a panchromatic cathodoluminescence system that allows the detection of cathodoluminescence in the wavelength range between 200‒900 nm. For instrument control, we can utilize the customized JEOL system software and the PC-based Probe for Windows software.

Applications

• Mineralogy.
• Geology.
• Meteorites.
• Semiconductors.
• Metals.
• Catalyzers.

Key Analytical Advantages

• 3 nm secondary electron resolution.
• Large crystal spectrometers for high detection sensitivity for trace element concentrations.
• Increased count rate without sacrificing energy resolution and P/B ratio.
• High accuracy of quantitative analysis.
• High resolving power (resolution) for adjacent x-rays.
• 2 WDS spectrometers dedicated to the quantitative analysis of light elements (B to O).
• Dual TMP system for clean sample environment.
• Combined WDS / EDS.

Techniques

• Quantitative WDS of elements from B to U.
• Semi-quantitative EDS of elements from Be to U.
• Panchromatic CL imaging.
• BSE imaging.
• SE imaging.
• X-ray intensity mapping.

Contact

Axel Wittmann
Associate Research Scientist
Axel.Wittmann@asu.edu
480.727.8732