Noun
a beam of ions moving in the same direction at the same speed
Source: WordNetIon beam lithography It is known that focused- ion beam lithography has the capability of writing extremely fine lines (less than 50 nm line and space has been achieved) without proximity effect. Source: Internet
Ion beam milling may also be used for cross-section polishing prior to SEM analysis of materials that are difficult to prepare using mechanical polishing. Source: Internet