Depth selective CEMS in the energy range 0 to 20 keV

Abstract The “depth selectivity” can be expressed by weight functions T E , Θ ( x ) giving the probability that electrons, starting in depth x , reach and leave the surface with an energy E , and an emission angle Θ relative to the surface normal. T E , Θ ( x ) was available up to now only for K conversion electrons of iron in the energy range 6.3–7.3 keV. To extend the available depth range for 57 Fe DCEMS, we calculated T E , Θ ( x ) for energies down to about 2 keV, and up to 14.4 keV, including K, L and M conversion and KLL Auger electrons. Based on these results a program has been developed to simulate for a given sample composition DCEMS and also ICEMS spectra. First results of electron transport calculations for the 19.6 keV L conversion electrons of 119 Sn indicate a reduced surface sensitivity in comparison to 57 Fe, but the depth resolution seems to be reasonably good for deep layers.