US 7,321,198 B2
Ion source with uniformity of radial distribution of ion beam intensity
Naoki Kubota, Tokyo (Japan); and Akihiro Horita, Tokyo (Japan)
Assigned to TDK Corporation, Tokyo (Japan)
Filed on Jun. 02, 2006, as Appl. No. 11/445,260.
Claims priority of application No. P2005-170007 (JP), filed on Jun. 09, 2005.
Prior Publication US 2007/0029501 A1, Feb. 08, 2007
Int. Cl. H01J 7/24 (2006.01); H01J 27/00 (2006.01)
U.S. Cl. 315—111.31  [315/111.81; 250/423 R] 8 Claims
OG exemplary drawing
 
1. An ion source, comprising:
a discharge chamber, in which is formed an opening;
a coil, provided outside said discharge chamber, for generating plasma within said discharge chamber;
an extraction electrode, which extracts ions in said plasma generated in said discharge chamber from said opening and generates an ion beam;
a power supply device, which supplies power to said coil; and
a control device, which repeatedly halts output power output from said power supply device over prescribed intervals, while maintaining a value of said output power at a value, set in advance, which renders radial direction distribution of ion beam intensity of said ion beam uniform.