Present and future of light element analysis with electron beam instruments

The developments in the field of quant. electron probe microanal (EPMA) of ultralight elements in the past 10 years discussed. It is shown that the matrix correction procedures have evolved to such a high level of performance that they are no longer a limiting factor in this particular field, provided that they are used in conjunction with consistent sets of mass absorption coeffs. A major improvement has been the introduction of new synthetic multilayer analyzer crystals that provide not only much higher peak intensities but sometimes also a strong suppression of higher order reflections. An addnl. advantage is their reduced sensitivity to peak shape alterations, which is one of the major practical problems in light element anal. The latter effect appears to be one of the major drawbacks in ultralight element analysis, because it requires that, in principle, all intensity measurements be carried out in an integral manner. Areas that still offer much room for improvement are the contamination with carbon and oxygen and the problems assocd. with electrically nonconducting materials.