Monte Carlo simulations of coaxial backscattered electrons in SEM

We simulate the trajectories of backscattered electrons within a SEM of particular detection geometry which is adapted to topographic contrast attenuation and Z atomic number contrast enhancement. The calculations are performed choosing the different experimentally possible conditions as regards the primary electron energy, the detector aperture angle and the energy window of the detected electrons. From such simulations, it is possible to deduce the backscattering coefficient and consequently the conditions which optimize the Z analysis, particularly in order to avoid confusion between Z and topographic contrast.