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(11)

EP 2 396 815 A2

(12)

(88) Date of publication A3: 28.10.2010 (43) Date of publication: 21.12.2011 Bulletin 2011/51 (21) Application number: 10741683.6 (22) Date of filing: 10.02.2010

(51) International Patent Classification (IPC):  H01L 21/66(2006.01) G01N 21/88(2006.01) (86) International application number: PCT/US2010/023802 (87) International publication number: WO 2010/093733 (19.08.2010 Gazette 2010/33)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR (30) Priority: 13.02.2009 US 152477 P (71) Applicant: KLA-Tencor Corporation Milpitas, CA 95035 (US)

(72) Inventors: HUANG, Junqing Fremont California 94536 (US) ZHANG, Yong Cupertino California 95014 (US) CHEN, Stephanie Fremont California 94555 (US) LUO, Tao Fremont California 94539 (US) GAO, Lisheng Morgan Hill California 95037 (US) WALLINGFORD, Richard San Jose California 95118 (US) (74) Representative: Lukaszyk, Szymon  Kancelaria Patentowa Lukaszyk ul. Glowackiego 8 40-062 Katowice 40-062 Katowice (PL)