Hollow target magnetron-sputter-type solid material ion source.

A thin-walled aluminum (Al) hollow electrode has been inserted into an ion source to serve as an electrode for a radio frequency magnetron discharge. The produced plasma stabilized by argon (Ar) gas sputters the Al electrode to form a beam of Al+ and Ar+ ions. The total beam current extracted through a 3 mm diameter extraction hole has been 50 μA, with the Al+ ion beam occupying 30% of the total beam current.