[Sneap] Helium in Freeman Ion Source

[Shon B Gilliam]

We have an Eaton NV-3204 medium current ion implanter system which uses a 
Freeman ion source. Does anyone have experience achieving a decent helium 
beam current from a system such as this. Recently, the implanter has been 
used for neon and carbon beams providing as much as ~100 uA and ~20 uA, 
respectively. However, we never get more than ~10 nA from helium. Any ideas 
about why we get so little helium beam and/or how to get much more?


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Shon B. Gilliam
Dept. of Physics & Astronomy
UNC-Chapel Hill
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