Photocopying – Projection printing and copying cameras – Focus or magnification control
Reexamination Certificate
2011-08-30
2011-08-30
Nguyen, Hung Henry (Department: 2882)
Photocopying
Projection printing and copying cameras
Focus or magnification control
C355S052000
Reexamination Certificate
active
08009274
ABSTRACT:
Focus monitoring for a photolithographic applications is provided by illuminating a photoresist layer with a light beam transmitted through a first binary mask to define a circuit pattern on an underlying substrate and then illuminating the photoresist layer with an unbalanced off-axis light beam transmitted through a second binary mask. The second mask contains a shifting feature configuration in one portion, while another portion blocks light transmission to the chip design area of the photoresist. After development of the photoresist layer, the pattern formed by illumination of the second mask can be compared with a predefined reference feature on the photoresist layer to determine whether a shift, if any, is within acceptable focus limits.
REFERENCES:
patent: 5418092 (1995-05-01), Okamoto
patent: 5936738 (1999-08-01), Liebmann et al.
patent: 6251564 (2001-06-01), Lin et al.
patent: 7396621 (2008-07-01), Fujisawa et al.
patent: 2002/0195539 (2002-12-01), Nakao et al.
patent: 2009/0092926 (2009-04-01), Gutmann et al.
Zhang, G. et al., Across Wafer Focus Mapping and Its Application in Advanced Technology Nodes, Optical Proceedings of SPIE, the International Society for Optical Engineering, Feb. 21-24, 2006, 10 pages, vol. 6154, Society of Photo-Optical Instrumentation Engineers, Bellingham, WA USA.
Brunner, T.A. et al, Simulations and Experiments with the Phase Shift Focus Monitor, Proceedings of SPIE, the International Society for Optical Engineering, 1996, pp. 236-243, vol. 2726, Society of Photo-Optical Instrumentation Engineers, Bellingham, WA USA.
Nakao, S. et al., Implementation of phase-shift focus monitor with modified illumination, Proceedings of SPIE, the International Society for Optical Engineering, Mar. 5, 2002, pp. 918-926, vol. 4691.
Advanced Micro Devices , Inc.
Ditthavong Mori & Steiner, P.C.
Nguyen Hung Henry
LandOfFree
In-die focus monitoring with binary mask does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with In-die focus monitoring with binary mask, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and In-die focus monitoring with binary mask will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2666063