Electron confinement inside magnet of ion implanter

摘要

A method and apparatus are disclosed for improving space charge neutralization adjacent a magnet of an ion implanter by confining the electrons inside a magnetic region thereof to reduce electron losses and therefore improve the transport efficiency of a low energy beam. A magnetic pole member for a magnet of an ion implanter is provided that includes an outer surface having a plurality of magnetic field concentration members that form magnetic field concentrations adjacent the magnetic pole member. Electrons that encounter this increased magnetic field are repelled back along the same magnetic field line rather than allowed to escape. An analyzer magnet and ion implanter including the magnet pole are also provided so that a method of improving low energy ion beam space charge neutralization in an ion implanter is realized.