Reduced Coulomb Interactions in a Multi-Beam Column

Performance of a multi-electron-beam system can be improved by reducing Coulomb effects in the illumination path of a multi-beam inspection system. A beam-limiting aperture with multiple holes can be positioned between an electron beam source and a multi-lens array, such as in a field-free region. The beam-limiting aperture is configured to reduce Coulomb interactions between the electron beam source and the multi-lens array. An electron beam system with the beam-limiting aperture can be used in a scanning electron microscope.