Overlay error detection

Optics: measuring and testing – By alignment in lateral direction – With registration indicia

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C356S399000, C382S151000

Reexamination Certificate

active

07375810

ABSTRACT:
An overlay target with gratings thereon is illuminated and radiation scattered by the target is imaged onto detectors. A phase difference is then detected between the outputs of the detectors to find the mis-alignment error. In another aspect, an overlay target with gratings or box-in-box structures is illuminated and radiation scattered by the target is imaged onto detectors located away from the specular reflection direction of the illumination in a dark field detection scheme. Medium numerical aperture optics may be employed for collecting the radiation from the overlay target in a bright or dark field configuration so that the system has a larger depth of focus and so that the two structures of the target at different elevations can be measured accurately at the same time. Analytical functions are constructed for the grating type targets. By finding the phase difference between the two gratings at different elevations, misalignment errors can be detected. Analytical functions are constructed as a model for box-in-box type targets where data points away from the edges of the box or bars can be used in the curve fitting. Symmetrical functions are employed to further reduce noise.

REFERENCES:
patent: 4662753 (1987-05-01), Yabu
patent: 4705593 (1987-11-01), Haigh et al.
patent: 4728193 (1988-03-01), Bartelt et al.
patent: 4871955 (1989-10-01), Berger
patent: 5000573 (1991-03-01), Suzuki et al.
patent: 5130554 (1992-07-01), Nose et al.
patent: 5182610 (1993-01-01), Shibata
patent: 5216257 (1993-06-01), Brueck et al.
patent: 5333050 (1994-07-01), Nose et al.
patent: 5343292 (1994-08-01), Brueck et al.
patent: 5465148 (1995-11-01), Matsumoto et al.
patent: 5495336 (1996-02-01), Nose et al.
patent: 5585923 (1996-12-01), Nose et al.
patent: 5610718 (1997-03-01), Sentoku et al.
patent: 5682239 (1997-10-01), Matsumoto et al.
patent: 5712707 (1998-01-01), Ausschnitt et al.
patent: 5751426 (1998-05-01), Nose et al.
patent: 5757507 (1998-05-01), Ausschnitt et al.
patent: 5808742 (1998-09-01), Everett et al.
patent: 5847974 (1998-12-01), Mori et al.
patent: 5917604 (1999-06-01), Dirksen et al.
patent: 5923041 (1999-07-01), Cresswell et al.
patent: 6023338 (2000-02-01), Bareket
patent: 6130750 (2000-10-01), Ausschnitt et al.
patent: 6317211 (2001-11-01), Ausschnitt et al.
patent: 6556305 (2003-04-01), Aziz et al.
patent: 6710876 (2004-03-01), Nikoonahad et al.
patent: 10-270347 (1998-10-01), None
R. Pforr, et al., “In-Process Image Detecting Technique For Determination Of Overlay, And Image Quality For ASM-L Wafer Stepper”, SPIE vol. 1674 Optical/Laser Microlithography V (1992) pp. 594-608.
“Microinterferometre differentiel a ondes polarises,” G. Nomarski, J. Phys Radium 16, (S-13S (1955).
“Lithography Process Control,” H. Levinson, SPIE press, vol. TT28, Bellingham, Washington, 1999.
International Preliminary Examination Report for corresponding PCT application No. PCT/US01/51287 dated May 30, 2003, 8 pages.
Written Opinion for corresponding PCT application No. PCT/US01/51287 dated Dec. 31, 2002, 7 pages.
Notification of the Transmittal of the International Search Report or the Declaration for corresponding PCT application No. PCT/US01/51287 dated Aug. 16, 2002, 6 pages.
Japanese Patent Office, “Notification of Reasons for Refusal,” dispatch date in related patent application 2004-521380 on Nov. 27, 2007, 9 pgs.
Amended Claims for Japanese Patent Application No. 2004-521380, Oct. 26, 2004, 12 pgs.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Overlay error detection does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Overlay error detection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Overlay error detection will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2751266

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.