The CAMCOR MicroAnalytical Facility provides resources for sample preparation and materials analysis by Electron Probe Micro Analysis (EPMA) and Environmental Scanning Electron Microscopy (ESEM).
- 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.
- Spatial resolution of 1 micrometer in x-y dimension and for thin films, can obtain composition and thickness of nanometer scale layers.
- Flexibility and accuracy in analyzing unknown samples of arbitrary composition by physics-based quantitative matrix correction procedures.
- Spatial distribution of elemental constituents can be visualized quantitatively by digital composition maps and displayed in gray scale or false color.
- 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.
- The scanning electron microscope focuses an electron beam while it is scanned across a sample’s surface.
- Secondary electrons emitted from the atoms on the top surface are used to construct quantitative 3 dimensional elevation models of complex surfaces, for example porous materials or fracture surfaces.
- Backscattered electrons are used to show the distribution of different chemical phases in the sample.
- Qualitative or quantitative elemental analysis at microscale can be achieved with Energy Dispersive X-ray Spectroscopy (EDS). X-rays may also be used to form maps or line profiles, showing the elemental distribution in a sample surface.
- Cathodo-luminescence emission is the result of band gap excitation in insulating and semi-conductor materials generally on the order of a few electron volts, and can produce visible light emission. These emissions are often correlated with trace elements and also lattice defects and/or crystallographic stresses.
- Electron Backscatter Diffraction (EBSD) patterning can provide texture and orientation information for crystalline materials.
- PDF of MicroAnalytical Facility Brochure available
- CAMCOR Testing Services Agreement (PDF)
- Geology 619 – Electron Beam Analysis (PDF)
|John J. Donovan
CAMCOR Microanalytical Facility