Electron Bombardment Ion Source for Low Energy Beams

Abstract
A high current, electron bombardment ion source of simple design and suitable for low energy ion beam production is described. The source produces ion beams in the energy range from a few electron volts to several kilo‐electron volts with an energy spread of a fraction of 1 eV, with high current density (5 μA/cm2 at 25 eV), and without the problems associated with rf ion sources. The source has been used successfully to produce low energy beams of noble gas ions such as He+ and Ar+ without metastable contamination, as well as for H2+ and N2+.