| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To make a current density of ion beams uniform in an ion gun having a plurality of filaments. <P>SOLUTION: In this ion gun, a cathode comprises a plurality of filaments extending in a longitudinal direction, and a grid has an ion beam extracting hole extending in a longitudinal direction. The ion gun comprises a plurality of main magnets arranged around the ion beam extracting hole, and arranged such that an S pole is directed to an ion beam emission direction and an N pole is directed to the opposite direction, respectively; at least four first auxiliary magnets arranged at ends of the plural main magnets symmetrically to a longitudinal direction and a width direction, and arranged such that an S pole is directed to a longitudinal inward direction and an N pole is directed to the opposite direction; and second auxiliary magnets arranged symmetrically to a width direction at a position corresponding to an isolation portion between the plural filaments, and arranged such that an N pole is directed to the ion beam emission direction and an S pole is directed to the opposite direction. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
