US 7,564,557 B2
Apparatus and methods for detecting overlay errors using scatterometry
Walter D. Mieher, Los Gatos, Calif. (US); Ady Levy, Sunnyvale, Calif. (US); Boris Golovanesky, Haifa, Ill. (US); Michael Friedmann, Mountain View, Calif. (US); Ian Smith, Los Gatos, Calif. (US); Michael E. Adel, Zichron Ya'akov, Ill. (US); and Anatoly Fabrikant, Fremont, Calif. (US)
Assigned to KLA-Tencor Technologies Corp., Milpitas, Calif. (US)
Filed on Oct. 29, 2007, as Appl. No. 11/926,603.
Application 11/926603 is a division of application No. 10/785732, filed on Feb. 23, 2004, granted, now 7,289,213.
Application 10/785732 is a continuation in part of application No. 10/729838, filed on Dec. 05, 2003, granted, now 7,317,531.
Claims priority of provisional application 60/504093, filed on Sep. 19, 2003.
Claims priority of provisional application 60/449496, filed on Feb. 22, 2003.
Claims priority of provisional application 60/498524, filed on Aug. 27, 2003.
Claims priority of provisional application 60/440970, filed on Jan. 17, 2003.
Claims priority of provisional application 60/431314, filed on Dec. 05, 2002.
Prior Publication US 2008/0049226 A1, Feb. 28, 2008
Int. Cl. G01B 11/00 (2006.01); G01B 11/14 (2006.01); G01B 11/04 (2006.01); G01B 11/08 (2006.01); G01N 21/00 (2006.01); G01N 23/00 (2006.01); G01N 21/86 (2006.01); G21K 7/00 (2006.01); G01V 8/00 (2006.01)
U.S. Cl. 356—401  [356/72; 356/625; 356/636; 250/311; 250/559.19; 250/559.3] 7 Claims
OG exemplary drawing
 
1. A single metrology tool, comprising:
a scatterometry overlay measurement system configured to measure overlay on a combined mark having a scatterometry overlay target disposed over a scatterometry CD or profile target; and
a CD-SEM system configured to measure critical dimension on the CD or profile target of the combined mark,
wherein the scatterometry overlay measurement system is configured to measure overlay on both the scatterometry overlay target and the scatterometry CD or profile target based on a scatterometry overlay technique without using calibration or a model regression technique, wherein the scatterometry overlay technique is a phase based technique that includes representing each measured optical signal as a set of periodic functions having a plurality of known parameters and an unknown overlay error parameter and analyzing the set of periodic functions to solve for the unknown overlay error parameter to thereby determine the overlay error.