Systems and methods that neutralize ion beams in implantation processes are
provided. The methods involve introducing a gas into the ion beam. The gas, for
example, can be introduced into a region defined by an electrode through which
the ion beam travels. The gas increases the generation of electrons in the beam
which, in turn, neutralizes the beam. The neutralized beam has a reduced tendency
to diverge (i.e., greater beam stability) during transport which can increase the
beam current delivered to the wafer and implant uniformity, amongst other advantages.
The systems and methods are particularly useful in limiting the divergence of low
energy ion beams.
