Electron flood apparatus for neutralising charge build-up on a substrate during ion implantation

摘要

Electron flood apparatus for neutralising positive charge build-up on a substrate during implantation of ions in a substrate by ion beam implantation apparatus. The electron flood apparatus comprises a tube (13) for axially receiving and passing an ion beam (12) to a substrate (10), an opening (14) in a sidewall of the tube, a plasma chamber (15) having an exit aperture (16) in communication with said opening of said tube, a supply (17) of inert gas to said plasma chamber, a high frequency power generator (19), and means (20,18) to deliver high frequency power from said generator to maintain a plasma in said chamber to produce low energy electrons, whereby a flux of said low energy electrons emerges from said chamber through said exit aperture into said tube to merge with the ion beam. <IMAGE>