Relation of iron, aluminum, and silicon layer thicknesses to the electron microprobe beam size

Nonconventional standards containing layers of known thicknesses of iron, aluminum, and silicon in a beryllium matrix were used to determine the effect of the size of a region enriched in these elements on the x-ray emission generated by an electron microprobe beam. These thicknesses were nominally 0.5, 1.0, 2.0, 5.0, and 10.0 $mu$m and represent regions with dimensions of the order of the effective spot size. By analyzing these layers, calibration curves were generated to allow corrections to be made to standard intensities used for quantitative analyses in this size regime. As a result, a procedure was developed to allow a more accurate quantitative analysis of regions as small as 0.5 $mu$m using characteristic x-ray emission. (auth)