(19)

(11)

EP 0 776 475 A1

(12)

(43) Date of publication: 04.06.1997 Bulletin 1997/23 (21) Application number: 95928591.0 (22) Date of filing: 18.08.1995

(51) International Patent Classification (IPC):  G01L 1/ 14( . ) G01P 15/ 125( . ) G01P 15/ 18( . ) G01P 15/ 08( . ) G01P 15/ 13( . ) H01L 29/ 84( . ) (86) International application number: PCT/GB1995/001966 (87) International publication number: WO 1996/006358 (29.02.1996 Gazette 1996/10)

(84) Designated Contracting States: DE ES FR GB IT NL SE (30) Priority: 18.08.1994 GB 19940016683 (71) Applicant: BRITISH TECHNOLOGY GROUP LIMITED London SE1 6BU (GB)	(72) Inventor: FAWCETT, John, Neville Jesmond Newcastle-upon-Tyne NE2 3NZ (GB) (74) Representative: Funnell, Samantha Jane  British Technology Group Ltd. Patents Department 101 Newington Causeway London SE1 6BU London SE1 6BU (GB)