Angular distribution of X-ray photoelectrons emitted from silver

The no-loss peak of Ag 3d photoelectrons and 3d XPS spectra at different incidence angles of X-rays were measured with a double angular photoelectron intelligent analyzers (DAPHNIA) attached to a wide energy range X-ray beam line BL15XU at SPring-8. Ag 3d X-ray photoelectron spectroscopy (XPS) spectra were simulated by a Monte Carlo (MC) method using an effective energy loss function. Confirming that the MC simulation based on the use of the effective energy loss function describes successfully Ag 3d XPS spectrum, we applied the MC simulation to the angular distribution of Ag 3d X-ray photoelectrons for different incidence angles of X-rays, and for different take-off angles of photoelectrons. The simulation results agree very well the experimental data for small and medium incidence angle; but there is a large discrepancy for X-ray glancing incidence due to stronger surface generations of photoelectrons in this case.