Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1995-04-13
1996-03-26
Sikes, William L.
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
250557, G01N 286
Patent
active
055023118
ABSTRACT:
A plane positioning apparatus comprises a projector for projecting beams to a given portion on the surface of a substrate in a diagonal direction, a light receiving device to receive beams reflected from the substrate surface and output photoelectric signals in accordance with variation of the light receiving position, a calculating circuit to output deviation signals in accordance with the deviation amount of the substrate surface with respect to a predetermined fiducial plane based on the deviation signals, a substrate shifting device to shift and set the substrate at a given position in a direction perpendicular to the fiducial plane in accordance with the deviation signals, a level variation detecting device to detect level variation of the deviation signals generated when the substrate surface and the fiducial plane are displaced interrelatedly, an inclination calculating device to calculate, in accordance with the level variation characteristics, the value of the inclination of the level variation characteristics at a point where the substrate surface and the fiducial plane are substantially matched, and a correction device to correct the allowable range set for the level variation characteristics in order to control the substrate shifting device in accordance with the difference between the inclination value and the fiducial value thus calculated.
REFERENCES:
patent: 4699515 (1987-10-01), Tanimoto et al.
patent: 4853745 (1989-08-01), Kamiya et al.
patent: 4902900 (1990-02-01), Kamiya et al.
patent: 4962318 (1990-10-01), Nishi
patent: 5015866 (1991-05-01), Hayashi
patent: 5153678 (1992-10-01), Ota
patent: 5241188 (1993-08-01), Mizutani
patent: 5323016 (1994-06-01), Yamada et al.
SPIE Optical/Laser Microlithography V, vol. 1674, 1992, pp. 741-752.
Imai Yuji
Tanaka Yasuaki
Wakamoto Shinji
Dudek James A.
Nikon Corporation
Sikes William L.
LandOfFree
Method of and apparatus for detecting plane position does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of and apparatus for detecting plane position, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of and apparatus for detecting plane position will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-917768