(19)

(11)

EP 0 898 782 A2

(12)

(43) Date of publication: 03.03.1999 Bulletin 1999/09 (21) Application number: 97926529.0 (22) Date of filing: 14.05.1997

(51) International Patent Classification (IPC):  H01J 9/ 02( . ) H01J 29/ 86( . ) H01J 31/ 15( . ) H01J 29/ 04( . ) H01J 31/ 12( . ) (86) International application number: PCT/US1997/008257 (87) International publication number: WO 1997/043781 (20.11.1997 Gazette 1997/50)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 14.05.1996 US 19960645615 31.12.1996 US 19960777797 09.04.1997 US 19970840084 (71) Applicant: Micron Technology, Inc. Boise, ID 83706-0006 (US)	(72) Inventors: CHADHA, Surjit, S. Meridian, ID 83642 (US) RASMUSSEN, Robert, T. Boise, ID 83706 (US) (74) Representative: Gowshall, Jonathan Vallance  FORRESTER & BOEHMERT Franz-Joseph-Strasse 38 80801 München 80801 München (DE)