ABSTRACT
The finely focused high-energy electron beam used to create the image in a scanning electron microscope (SEM) happens also to generate characteristic X-rays in the parts of the specimen exposed to it, and can therefore be used as a chemical ‘probe’. An SEM equipped with a suitable X-ray analyser provides a versatile, non-destructive means of analysing chemical variation on the micrometre scale in the specimen surface. ‘Electron probe microanalysis’ (EPMA) has found innumerable applications in earth science, metallurgy, solid-state physics, biology and environmental science. General reviews of the subject are given by Potts (1987), Goldstein et al. (1992), Reed (1993, 1995) and Champness (1995).
