Patent SG-11201901331Y-A (SG)
Title: Method for defocus detection
Inventor: JIANG XUGUANG
IPC: H01L21/66
Filed: 2017-09-15
Abstract: INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property 11111111111 0111010101111101111101 0 011111001H01111101H 011111E111111111111 Organization International Bureau (10) International Publication Number (43) International Publication Date .....0\"\" WO 2018/057433 Al 29 March 2018 (29.03.2018) WI P0 I P C T (51) International Patent Classification: Yong; 20781 Cheryl Drive, Cupertino, California 95014 HO1L 21/66 (2006.01) (US). (21) International Application Number: (74) Agent: MCANDREWS, Kevin et al.; KLA-Tencor Corp., (22) PCT/US2017/051901 Legal Department, One Technology Drive, Milpitas, Cali- fornia 95035 (US). International Filing Date: 15 September 2017 (15.09.2017) (81) Designated States (unless otherwise indicated, for every (25) Filing Language: English kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, BZ, (26) Publication Language: English CA, CH, CL, CN, CO, CR, CU, CZ, DE, DJ, DK, DM, DO, (30) Priority Data: DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, 62/399,251 23 September 2016 (23.09.2016) US HR, HU, ID, IL, IN, IR, IS, JO, JP, KE, KG, KH, KN, KP, 15/669,030 04 August 2017 (04.08.2017) US KR, KW, KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, (71) Applicant: KLA-TENCOR CORPORATION [US/US]; OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, Legal Department, One Technology Drive, Milpitas, Cali- SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, fornia 95035 (US). TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (72) Inventors: JIANG, Xuguang; 750 Brahms Way, Apt. 16, (84) Designated States (unless otherwise indicated, for every Sunnyvale, California 94087 (US). LI, Shifang; 3357 Sage- kind of regional protection available): ARIPO (BW, GH, wood Court, Pleasanton, California 94588 (US). ZHANG, GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, TZ, = Title: METHOD FOR DEFOCUS DETECTION = (54) 300 = \, = 301 = = Z = = 302 — (..-----/ Y X = 303 304 307 \ I L P = 305 = = = = 306 FIG. 5 ,-, M en si. (57) : Two or more color data can be combined to form a new data source to enhance sensitivity to defocus signal. Defocus IN detection can be performed on the newly formed data source. In a setup step, a training wafer can be used to select the best color 11 in © combination, and obtain defocus detection threshold. This can include applying a segment mask, calculating mean intensities of the ---- segment, determining a color combination that optimizes defocus sensitivity, and generating a second segment mask based on pixels GC , 1 that are above a threshold to sensitivity. In a detection step, the selected color combination is calculated, and the threshold is applied 0 to ei obtain defocus detection result. C [Continued on next page] WO 2018/057433 Al IMEDIMOM0101011MERI00 IIMINEHNOMOVOIMIE UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, MC, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, SM, TR), OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ, GW, KM, ML, MR, NE, SN, TD, TG). Published: — with international search report (Art. 21(3))