EFFECT OF ELASTIC-SCATTERING AND CYLINDRICAL MIRROR ANALYZER GEOMETRYON THE EVALUATION OF ESCAPE DEPTHS OF AUGER ELECTRONS

We have studied the effect of elastic scattering and analyser geometry on calculations of electron escape depths. A theoretical analysis of the electron escape depth has been presented that shows how it is rela ted to the solid angle for detection and the geometrical configuration of a cylindrical mirror analyser. To estimate the extent to which ela stic scattering can modify the values of the escape depth, Monte Carlo simulations of the emission of Auger electrons were carried out for C u MVV (59 eV), Cu LMM (916 eV), Au NW (238 eV) and Au MNN (2025 eV) si gnals. From the calculated depth distributions of signal electrons, we have derived a correction factor for the electron escape depth in ter ms of the corresponding inelastic mean free path which includes both t he effects of elastic scattering and analyser geometry. We have found that elastic scattering reduces the value of the escape depth by sever al tens of per cent and, depending on the target, signal electron ener gy and analyser geometry, the ratio between the escape depth and the i nelastic mean free path varies from 0.4 to 0.6.