MicroAnalytical Facility John Donovan

Electron Probe Micro Analysis (EPMA)

Left - Mg K-alpha x-ray map of a highly deformed metamorphic schist with garnet crystals

Right - Comparison of performance in modeling thin film specimen structure using homogeneous vs. replicate models

EMPA Provides:

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Electron Probe Microanalysis (EPMA) is an elemental analysis technique that uses a focused beam of high-energy electrons to non-destructively ionize a solid specimen surface, which induces emission of x-rays that are characteristic to the elements.

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Spatial resolution of approximately 1 micrometer

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Flexibility and accuracy in analyzing unknown samples of arbitrary composition by physics-based quantitative matrix correction procedures.

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Spatial distribution of elemental constituents can be visualized quantitatively by digital composition maps and displayed in gray scale or false color.

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Detection limits are of the order of 100 ppm (0.01 wt%) with wavelength dispersive spectrometry and 1000 ppm (0.1 wt%) with energy dispersive spectrometry.

Typical Applications:

Metallurgical studies, failure analysis, thin film, particulate analysis, mineral analysis, igneous petrology, semiconductor materials ceramic analysis, anthropological studies, art history and many others.