RF ELECTRON SOURCE FOR IONIZING GAS CLUSTERS

摘要

The present invention discloses a system and method for generating gas cluster ion beams (GCIB) having very low metallic contaminants. Gas cluster ion beam systems are plagued by high metallic contamination, thereby affecting their utility in many applications. This contamination is caused by the use of thermionic sources, which impart contaminants and are also susceptible to short lifecycles due to their elevated operating temperatures. While earlier modifications have focused on isolating the filament from the source gas cluster as much as possible, the present invention represents a significant advancement by eliminating the thermionic source completely. In the preferred embodiment, an inductively coupled plasma and ionization region replaces the thermionic source and ionizer of the prior art. Through the use of RF or microwave frequency electromagnetic waves, plasma can be created in the absence of a filament, thereby eliminating a major contributor of metallic contaminants.