An introduction to analytical electron microscopy

Abstract Analytical electron microscopy combines the techniques of high resolution electron microscopy and high sensitivity X-ray microanalysis on thin specimens. Elemental analysis depends upon the characteristic X-ray spectrum generated by the electrons passing through the specimen. This spectrum is analysed either by X-ray wavelength dispersion using crystal spectrometers or by non-dispersive energy discrimination using solid state or gas flow counters. Areas as small as 2,000A diameter can be chosen for analysis by focusing the illumination with a ‘minilens’ while observing the image on the fluorescent screen. There are many advantages in performing analysis on thin specimens. The area of analysis is always exactly located; specimen damage is minimal and corrections for absorption and fluorescence, usually necessary in analysis of bulk material, are negligible with thin specimens.