Performance of an electron beam ion trap as an ion source

The objective of this paper is to show that the Electron Beam Ion Trap (EBIT) can be used as an efficient source of high-quality, high-charge-state, high-Z ions. This is demonstrated by producing and extracting ions up to Th
⁸⁰⁺
and U
⁷⁰⁺
with EBIT. These ions were produced after injecting low-charge-state Th and U ions initially from a Metallic Vapor Vacuum Arc ion source into the trap. Measurements and calculations indicate that the background pressure in the trap is less than 10
^-10
Torr. With an electron beam current density of 3000 A/cm
²
, the extracted ions provide microsecond-wide ion beam pulses of about 10
⁴
ions per second. The duty cycle is determined by the time it takes for the charge state distribution to reach steady-state, which is 1 second for Th and U. The extracted ions can be used as a beam of slow (few e V kinetic energy), very-highly-charged (more than 100 keV per ion potential energy) ions for solid surface modification and processing.