Auger electron emission from Al induced by keV Ar bombardment: Experiments and Monte Carlo simulations

We have used a Monte Carlo program to study the Al L₂,3 Auger electron spectra induced by 1--10-keV Ar ions at 45^∘{} incidence. From a comparison of experimental intensities of the main atomic line and the number of excited sputtered recoils we have evaluated the relative role of symmetric and asymmetric exciting collisions. Angular and energy distributions of the excited sputtered atoms were calculated for different L₂,3 vacancy lifetimes in the solid, and from these distributions we obtained the energy shifts of the Auger energies. By including the interaction between the metal surface and the excited sputtered atoms we have reproduced the shape of the main atomic line for various values of the projectile energy.