Angular and energy distribution of backscattered electrons simulated by Monte-Carlo—Assessment by experiment I

The angular and energy distributions of backscattered electrons for the primary energies of 0.2, 0.5 and 1 keV and for Cu and Au were calculated by Monte-Carlo method and compared to measurement. The elastic differential cross-sections were calculated by ELSEPA code. For inelastic scattering a modified Tougaard's model of universal cross-section was used. We fit inelastic mean free path (IMFP) obtained from energy loss distribution, given by the modified Tougaard's model, in order they agreed with the value of IMFP from the TPP-2 formula. By this way we obtained an energy-dependent correction of the constants in Tougaard's formula. A very good agreement was found for the calculated and measured values of angular distribution of elastically reflected electrons. For the energy distribution of backscattered electrons some differences between experiment and calculation appeared, which were probably caused mainly by very low energy losses, e.g. losses at exiting of bremsstrahlung radiation.