Photocopying – Projection printing and copying cameras – Step and repeat
Patent
1995-05-04
2000-01-25
Moses, R. L.
Photocopying
Projection printing and copying cameras
Step and repeat
355 55, 355 67, G03B 2742, G03B 2752, G03B 2754
Patent
active
060183845
ABSTRACT:
A projection exposure system for printing the pattern formed on a reticle onto a wafer includes a reticle stage (5) and a wafer stage. A first reference plate (9) having a first reference pattern (MM1) formed thereon is mounted on the reticle stage (5), and a second reference plate (25) having a second reference pattern (WM1) formed thereon is mounted on the wafer stage. The first reference pattern (MM1) comprises two cross-marks (60a, 60b) spaced apart from each other in X-direction, and the second reference pattern (WM1) comprises two cross-marks (61a, 61b) spaced apart from each other in X-direction., Images of the cross-marks (61a, 61b) of the second reference pattern (WM1) are formed through a projection optical system (2) on the reticle stage (5) and superimposed with the cross-marks (60a, 60b) of the first reference pattern (MM1). A pair of observation optical systems (10, 11) spaced apart from each other in X-direction are used to observe the superimposed images of the corresponding cross-marks (60a and 61a, 60b and 61b), so as to determine the position shifts in X-direction between the corresponding superimposed images at two positions spaced from each other in X-direction. The determined position shifts are used to calculate the variation in projection magnification. The projection exposure system is capable of quick and high precision detection of the magnification of the projection optical system (2).
REFERENCES:
patent: 4629313 (1986-12-01), Tanimoto
patent: 5214489 (1993-05-01), Mizutani et al.
patent: 5406373 (1995-04-01), Kamon
patent: 5408320 (1995-04-01), Katagiri et al.
patent: 5414514 (1995-05-01), Smith et al.
patent: 5506684 (1996-04-01), Ota et al.
patent: 5528027 (1996-06-01), Mizutani
patent: 5661546 (1997-08-01), Taniguchi
Moses R. L.
Nikon Corporation
Virmani Shival
LandOfFree
Projection exposure system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Projection exposure system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Projection exposure system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2319350