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(11)

EP 0 198 908 A1

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(43) Date of publication: 29.10.1986 Bulletin 1986/44 (21) Application number: 85905575.0 (22) Date of filing: 25.10.1985

(51) International Patent Classification (IPC):  G03F 1/ 00( . ) H01J 37/ 317( . ) (86) International application number: PCT/US1985/002109 (87) International publication number: WO 1986/002774 (09.05.1986 Gazette 1986/10)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 26.10.1984 US 19840665251 26.08.1985 US 19850769370 (71) Applicants: ION BEAM SYSTEMS, INC. Beverly, MA 01915 (US) MASSACHUSETTS INSTITUTE OF TECHNOLOGY Cambridge, MA 02139 (US)	(72) Inventors: KELLOGG, Edwin, M. Lexington, MA 02173 (US) MELNGAILIS, John Newton, MA 02160 (US) (74) Representative: Heidrich, Udo, Dr. jur., Dipl.-Phys.  Rechtsanwalt & Patentanwalt Dipl.-Phys. Dr. jur. U. HEIDRICH Franziskanerstrasse 30 D-81669 München D-81669 München (DE)