(19)

(11)

EP 0 672 302 A1

(12)

(43) Date of publication: 20.09.1995 Bulletin 1995/38 (21) Application number: 92923643.0 (22) Date of filing: 01.12.1992

(51) International Patent Classification (IPC):  H01L 29/ 417( . ) H01L 29/ 786( . ) (86) International application number: PCT/CA1992/000520 (87) International publication number: WO 1994/013019 (09.06.1994 Gazette 1994/13)

(84) Designated Contracting States: DE FR GB NL (71) Applicant: LITTON SYSTEMS CANADA LIMITED Etobicoke Ontario M9W 5A7 (CA)	(72) Inventor: FARRELL, James, F. Etobicoke, Ontario M9W 5A7 (CA) (74) Representative: Naismith, Robert Stewart, et al  CRUIKSHANK & FAIRWEATHER 19 Royal Exchange Square Glasgow, G1 3AE Scotland Glasgow, G1 3AE Scotland (GB)