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X-Ray Microanalyses in the Variable Pressure (Environmental) Scanning Electron Microscope



Dale E. Newbury


Electron-excited x-ray microanalysis performed in the variable pressure and environmental scanning electron microscopes is subject to additional artifacts beyond those encountered in the conventional scanning electron microscope. Gas scattering leads to direct contributions to the spectrum from the environmental gas, as well as remote generation of x-rays by electrons scattered out of the focussed beam. The analyst can exert some degree of control over these artifacts, but depending on the exact situation, spurious elements can appear at the trace ( 0.1 mass fraction) levels. Dispersed particle samples give the least compromised results, while fine scale microstructures are the most severely compromised. Procedures to optimize the situation based upon specimen preparation as well as spectral processing are described.
Journal of Research (NIST JRES) -
107 No. 6


energy dispersive x-ray spectrometry, environmental, scanning electron microscopy, variable pressure, x-ray mapping, x-ray microanalysis, x-ray spectrometry


Newbury, D. (2002), X-Ray Microanalyses in the Variable Pressure (Environmental) Scanning Electron Microscope, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed June 13, 2024)


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Created November 1, 2002, Updated February 17, 2017