A Monte Carlo calculation of low-energy secondary electron emission from metals

A Monte Carlo simulation is applied to investigate the escape process of the secondary electrons in a metal. The calculated energy distribution of secondary electrons agrees satisfactorily with the experimental results. The lateral distribution of secondary electrons is also calculated and is similar 10 Å for normal incidence, which corresponds to the theoretical limit of the scanning electron microscope in the image of secondary electrons. The decay of slow secondary electrons is shown not to obey a simple exponential decay law because of the cascade process from the calculation of the depth distribution. The calculated results suggest that a higher resolution in the scanning electron microscope can be attained by detecting only the secondary electrons with higher energies. The energy distribution of secondary electrons excited by Auger electrons is widely spread over the range between zero and the characteristic energy of Auger electrons.