Focus detecting method and apparatus

Details Focus detecting method and apparatus Focus detecting method and apparatus

1995-09-12

1997-07-22

Grimley, Arthur T.

Photocopying

Projection printing and copying cameras

Focus or magnification control

355 53, 250548, 396111, 396116, 396118, H01L 2130, G03B 2752

Patent

active

056508409

ABSTRACT:
A method of detecting a focus position of a projection optical system at a high throughput and with high accuracy. A sensor pattern (SP) which is provided on a wafer stage (WS) as a light-receiving part of a photoelectric sensor (PES) is moved in the direction of an optical axis (AX) of a projection optical system (PL), and at the same time, it is moved in a direction (X) perpendicular to the optical axis (AX). While doing so, a reticle pattern (RP) which is provided on a reticle (R) is illuminated by illuminating light (IL) for exposure, and an image of the reticle pattern (RP) is formed on the sensor pattern (SP) through the projection optical system (PL). Light passing through the sensor pattern (SP) is received by the photoelectric sensor (PES), and a focus position is detected on the basis of the intensity of the transmitted light.

REFERENCES:
patent: 3904869 (1975-09-01), Stauffer
patent: 4441810 (1984-04-01), Momose et al.
patent: 4540277 (1985-09-01), Mayes et al.
patent: 4629313 (1986-12-01), Tanimoto
patent: 4650983 (1987-03-01), Suwa
patent: 4689480 (1987-08-01), Stern
patent: 4829193 (1989-05-01), Nishi
patent: 4952815 (1990-08-01), Nishi
patent: 5241188 (1993-08-01), Mitzutani
patent: 5420438 (1995-05-01), Sensui et al.

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