I used to work for a company that built Ion Implanters - which turned wafers of pure silicone into semi-conductor material for computer chips, using an Ion beam.
A wheel spinning at 1250 RPM, which had 20 seven inch silicon discs on its spokes, scanning backwards and forwards through an Ion beam that was firing different weights of Ions at the silicone - the heavier the Ions the deeper they penetrated, allowing multiple levels of tracks in the silicone. All done in a vacuum achieved by Edwards roughing pumps, followed by turbo pumps followed by cryogenic pumps . . . the weights of the Ions were determined by an analysing magnet that bent the Ion beam by 90 degrees. The strength of the electro magnet determined what weight of Ion would bend exactly 90 degrees and therefore hit the wafers - heavier Ions not quite making it, lighter ones bending too much. . . . really clever stuff and very difficult to look at the massive hardware and relate it to the result being something you can only see under a microscope!
