Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1996-01-02
1997-02-11
Westin, Edward P.
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
25055920, 356401, 355 53, G03B 2742
Patent
active
056023995
ABSTRACT:
A surface position detecting apparatus is suitable for detecting a position of a surface of the substrate supported by a support means in an exposure apparatus. The surface position detecting apparatus comprises a light source, an irradiation optical system for irradiating light from the light source obliquely onto the substrate surface and forming an image of a measurement pattern of a pattern plate on the substrate surface, and a converging optical system for converging light irradiated from the irradiation optical system and then reflected by the substrate surface to re-image the image of the measurement pattern on a photodetector surface. The photodetector can detect the surface position based on the position of pattern image re-imaged on the photodetector surface. The image of the measurement pattern comprises a linear image extending in a predetermined direction. Also, a direction in which the line image of the measurement pattern on the substrate surface is displaced when the substrate is vertically moved is neither parallel nor perpendicular to a longitudinal direction of the measurement pattern image.
REFERENCES:
patent: 4558949 (1985-12-01), Uehara et al.
patent: 4874954 (1989-10-01), Takahashi et al.
patent: 4902900 (1990-02-01), Kamiya et al.
patent: 4952970 (1990-08-01), Suzuki et al.
patent: 5015866 (1991-05-01), Hayashi
patent: 5118957 (1992-06-01), Kawashima et al.
patent: 5124562 (1992-06-01), Kawashima et al.
patent: 5414515 (1995-05-01), Kawashima
patent: 5416562 (1995-05-01), Ota et al.
patent: 5434425 (1995-07-01), Ishiyama
Lee John R.
Nikon Corporation
Westin Edward P.
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