Formulae for light-element microanalysis by electron energy-loss spectrometry.

Simple expressions are derived for elemental concentration in terms of quantities measurable from the energy-loss spectrum and suitable cross sections for inner-shell excitation. The derivation takes into account the predominant scattering processes occurring in a thin sample: elastic and quasi-elastic scattering and valence-electron excitation. Consideration is given to the choice of specimen orientation and thickness, the detection angle and energy window, from the point of view of accuracy of the simple formulae and other factors. The requirements for displaying chemical information in an energy-filtered image are discussed briefly.