ELECTRON PROBE (EPMA)
An electron microprobe, also defined as an electron probe micro analyzer or electron microprobe analyzer, is a kind of measuring instruments which used to detect the chemical structure of relatively small quantities of bulk objects in a non-destructive manner. EPMA is a technology for obtaining specific and reliable quantitative chemical tests of our specimens’ micron size ranges.
EPMA operates by hitting a sample in micro-volume with a concentrated electron beam (average energy = 5-30 keV) and gathering the X-ray photons produced by different chemical components. An electron microprobe works on the assumption that when a solid substance is probed with an amplified and targeted beam of electrons, the incoming electron beam has enough energy to release both energy and matter from the specimen.
EPMA equipment have a complete collection of developed microscope tools that enable continuous X-ray, SEM, and BSE imaging, as well as advanced light source microscopes; they offer extremely versatile sample screening with image magnification ranging from 40 to 400,000.
- To determine which elements make up a material, irradiate it using electron beams and measure the distinctive X-ray that is produced.
- In certain situations, a mineral’s U-Th age, such as monazite, may be determined without testing isotopic ratios.
- EPMA is also often used to examine synthetic materials such as optical wafers, thin films, microcircuits, semi-conductors, and superconducting ceramics.
- The most often used approach for the chemical examination of geological materials at small scales is quantitative EPMA analysis.
Electron Probe Micro-Analyzer Fundamental Principles (EPMA) An electron microprobe begins with the idea that when a solid substance is attacked with an amplified and concentrated electron beam, the incoming beam of electrons has enough energy to release both energy and matter from specimen.
- Some elements produce x-rays with overlap peak regions (both in terms of power and wavelength) that must be separated.
- The electron probe is incapable of detecting the lightest elements (H, He, and Li).
- Probe analysis is also unable of distinguishing between the various valences states of Fe.