College of Science and Engineering

Surface analysis

Energy Dispersive X-Ray Spectroscopy (EDS) is an analytical technique which provides surface elemental analysis and is available on our Transmission Electron Microscope (TEM), Scanning Transmission Electron Microscope (STEM), Focused Ion beam /SEM(Dualbeam) and all our Field Emission Gun Scanning Electron Microscopes.

When an electron beam interacts with a specimen characteristic x-rays are produced. The energy and number of the X-rays emitted can be measured using an EDS detector.

Within AMC all the EDS detectors are silicon drift detectors and therefore can achieve a high count rate, which reduces the acquisition time. It also provides the ability to reduce the beam current which will reduce the interaction volume produced by the electron beam and provide better resolution for the lighter elements such as Carbon and Boron.

Wavelength-dispersive X-ray spectroscopy (WDXS or WDS) is a method used to count the number of X-rays of a specific wavelength diffracted by a crystal. The wavelength of the impinging X-ray and the crystal's lattice spacings are related by Bragg's law and produce constructive interference if they fit the criteria of Bragg's law. Unlike the related technique of energy-dispersive X-ray spectroscopy (EDS), WDS reads or counts only the X-rays of a single wavelength at a time, not producing a broad spectrum of wavelengths or energies simultaneously. WDS is primarily used in chemical analysis and has much higher accuracy and sensitivity than EDS analysis. For WDX samples should be flat and parallel on both sides, with one face well-polished.

In addition to this the AMC has:

  • Mineral analysis
  • Micro XRF analysis
  • Cathodoluminescence

For further information on access to any of the instruments please contact

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