(19)

(11)

EP 0 151 585 A1

(12)

(43) Date of publication: 21.08.1985 Bulletin 1985/34 (21) Application number: 84902405.0 (22) Date of filing: 04.06.1984

(51) International Patent Classification (IPC):  H01L 29/ 78( . ) H01L 21/ 265( . ) H01L 29/ 167( . ) H01L 21/ 225( . ) H01L 21/ 322( . ) (86) International application number: PCT/US1984/000851 (87) International publication number: WO 1985/000694 (14.02.1985 Gazette 1985/04)

(84) Designated Contracting States: BE DE FR GB NL (30) Priority: 25.07.1983 US 19830516755 (71) Applicant: AT&T Corp. New York, NY 10013-2412 (US)	(72) Inventors: KELLY, Michael, James Orefield, PA 18069 (US) LEVINSTEIN, Hyman, Joseph Berkeley Heights, NJ 07922 (US) MURARKA, Shyam, Prasad Murray Hill, NJ 07974 (US) YANEY, David, Stanley Bethlehem, PA 18017 (US) (74) Representative: Watts, Christopher Malcolm Kelway, Dr.  AT&T (UK) Ltd. 5, Mornington Road Woodford Green Essex, IG8 0TU Woodford Green Essex, IG8 0TU (GB)