Estimation of surface excitation correction factor for 200-5000 eV in Ni from absolute elastic scattering electron spectroscopy

Abstract

We have determined the surface plasmon excitation correction (SEC) factor for nickel in the 200-5000 eV range from the ratios of the absolute elastic scattering electron intensities measured by a novel cylindrical mirror analyser and those by the Monte Carlo method. The inelastic mean free paths (IMFPs) of nickel used for the Monte Carlo method in the energy range specified were calculated by the Penn algorithm. The resulting SECs were smaller than the values calculated from Chen and Oswald general equations of surface excitation parameters (SEPs), which describe the influence of surface plasmon excitations by electrons crossing a solid surface. We also found that SEPs (obtained from SECs) could be fitted to the equation P s (α, E) = C/[E n cos(α) + C] or P s (α, E) = aE -b / cos(α) (<7% root-mean-square error) in the 200-5000 eV energy range, where P s is the SEP, a is the surface crossing angle of the electron to the surface normal, n(= 0.41), C(= 5.39), a(= 1.7) and b(= 0.29) are parameters and E is the electron energy.