It is well known fact that the Auger electrons are produced by back-scattered electrons (BSE) as well as by a primary electron beam. Therefore, it becomes very important to consider the effect of BSE on AES signal from buried layer in a sample.
We selected the case of Au layer buried in Ni for Au Auger transition, M5N67N67, and calculated the Auger backscattering factor (ABF) for this transition and for this layer versus its depth. The MC simulation technique used for layered system reveals that ABF for buried layer of thickness 10 A changes with the increasing depth (from 0 to about 3 inelastic mean free paths) from 1.55 to 1.9 for primary electron beam energy of 5 keV. As can be expected the ABF for thicker Au layer takes greater values. This phenomenon can be explained in terms of excitation depth distribution function.
The results obtained are very useful when the variation in the ABF is expected to be the most important matrix effect, as can happen for a layered system investigated by the technique known as the Auger depth profiling.
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