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



Dale E. Newbury


X-ray spectra measured on uncoated insulators in the low voltage scanning electron microscope (LVSEM) and the variable pressure environmental scanning electron microscope (VP-ESEM) are subject to artifacts due to charging effects despite the capability of obtaining stable SEM imaging under these conditions. Spectral features are investigated that can be used to reveal anomalous charging conditions to avoid or at least recognize such artifacts. The Duane-Hunt limit of the x-ray continuum is a valuable tool for examining the incident beam energy which responds to charging conditions, but the dynamic nature of charging can introduce time dependent effects that can mask the expected effects. Protocols are described to evaluate the charging situation and to minimize or even eliminate it while retaining the ability to examine unmodified surfaces.
Journal of Research (NIST JRES) -
107 No. 6


Duane-Hunt limit, electron probe microanalysis, energy dispersive spectrometry, microbeam analysis, scanning electron microscopy, x-ray spectrometry


Newbury, D. (2002), X-Ray Microanalyses in the Variable Pressure (Environmental) Scanning Electron Microscopy, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed July 20, 2024)


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Created December 1, 2002, Updated February 17, 2017