Barbara Armbruster, Michael Cable, Ewa Kosmowska, Kim Larsen, Patrick Trimby and Ronald Vane
Plasma cleaners have been recognized as a necessary accessory for rapidly and effectively eliminating hydrocarbon contamination from vacuum chambers and samples. Operating at turbopump pressures, the Evactron plasma radical source with a unique RF hollow cathode generates a low-temperature RF plasma to create oxygen radicals when air is the feed gas. The oxygen radicals combine with surface hydrocarbons to form gaseous phases which are removed by the pumping system. The benefits of plasma cleaning include faster pumpdown times, improved image quality of serial block-face SEM volumetric sets, prevention of hydrocarbon deposition during imaging and no damage to EDS detectors or x-ray windows due to oxygen radical generation.