Optics: measuring and testing – By polarized light examination – With light attenuation
Patent
1997-11-26
1999-04-13
Pham, Hoa Q.
Optics: measuring and testing
By polarized light examination
With light attenuation
356446, 235462, 235455, G06K 710
Patent
active
058943480
ABSTRACT:
A scribe mark reader (10) uses a source of circularly polarized light and a holographic beam-shaping optical element (40) to uniformly illuminate an area of a substrate (20) that includes a scribe mark (18). Light incident on the substrate at a scribe mark is predominantly scattered, whereas light incident on the substrate at a processed area (30) of the wafer surface between the pits (28) of the scribe mark is predominantly specularly reflected. The phase-reversed, specularly reflected light from the processed area is blocked by a circular analyzer that passes light scattered from the scribe mark. Light passing the polarizer can then be used to form an image of the scribe mark. The intensity of the images formed are sufficiently consistent that the automatic gain control of the CCD camera can be used and the images formed can be readily interpreted by optical character recognition software.
REFERENCES:
patent: 3581100 (1971-05-01), Milford
patent: 3812374 (1974-05-01), Tuhro
patent: 4019026 (1977-04-01), Nakanishi et al.
patent: 4418467 (1983-12-01), Iwai
patent: 4435732 (1984-03-01), Hyatt
patent: 4444492 (1984-04-01), Lee
patent: 4471385 (1984-09-01), Hyatt
patent: 4636080 (1987-01-01), Feldman
patent: 4672457 (1987-06-01), Hyatt
patent: 4704027 (1987-11-01), Phillips
patent: 4732473 (1988-03-01), Bille et al.
patent: 4769523 (1988-09-01), Tanimoto et al.
patent: 4782751 (1988-11-01), Colapinto
patent: 4818847 (1989-04-01), Hara et al.
patent: 4864629 (1989-09-01), Deering
patent: 4884178 (1989-11-01), Roberts
patent: 4926409 (1990-05-01), Tsuyuguchi
patent: 5048968 (1991-09-01), Suzuki
patent: 5053612 (1991-10-01), Pielemier et al.
patent: 5109432 (1992-04-01), Hori et al.
patent: 5149948 (1992-09-01), Chisholm
patent: 5177346 (1993-01-01), Chisholm
patent: 5197105 (1993-03-01), Uemura et al.
patent: 5231536 (1993-07-01), Wilt et al.
patent: 5239169 (1993-08-01), Thomas
patent: 5265170 (1993-11-01), Hine et al.
patent: 5371347 (1994-12-01), Plesko
patent: 5386481 (1995-01-01), Hine et al.
patent: 5406060 (1995-04-01), Gitin
patent: 5449892 (1995-09-01), Yamada
patent: 5469294 (1995-11-01), Wilt et al.
patent: 5515452 (1996-05-01), Penkethman et al.
patent: 5585615 (1996-12-01), Iwanami et al.
Brochure entitled "Self-Illuminating Camera System (SICS)," of Stahl Research Laboratories, Inc., 3 Westchester Plaza, Elmsford, NY 10523, 2 pages (undated but believed to have been published by Jan. 1990).
Brochure entitled "HineSight.RTM. Wafer I.D. Reader," of Hine Design, 1901 Embarcadero Road #104 Palo Alto, CA 94303, 2 pages (undated).
Bacchi Paul
Filipski Paul S.
Kensington Laboratories, Inc.
Pham Hoa Q.
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