Method and apparatus for inspecting surfaces for contrast variat

Image analysis – Histogram processing – For setting a threshold

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358101, 358106, 358107, G06K 900

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050919636

ABSTRACT:
A method of and apparatus for inspecting the surface of an article for isolated contrast variations by illuminating the surface, forming an image of the surface from the reflected light, the image being composed of pixels that contain digitized information indicative of the relative intensity level of light reflected from a particular portion of the surface, comparing the intensity levels of at least some of the pixels to a predetermined intensity threshold to identify portions of the surface contrasting with other portions of that surface, and determining from the identified pixels the number of isolated contrast variations on the surface and the area of each of the variations. The number and size of the contrast variations appearing on the inspected article surface are compared to acceptability criteria to decide whether the article is acceptable for a particular use or in particular channels of commerce.

REFERENCES:
patent: 4547987 (1985-10-01), Peterson
patent: 4669123 (1987-05-01), Kobayashi et al.
patent: 4670779 (1987-06-01), Nagano
patent: 4736851 (1988-04-01), Ricros et al.
patent: 4771468 (1988-09-01), Batchelder et al.
patent: 4823194 (1989-04-01), Mishima et al.
patent: 4881269 (1989-11-01), Billiotte et al.
Rosenfeld, Azriel, "Edge Detection", Digital Picture Processing, Academic Press, Chapters 10.2 and 11.3, pp. 84-96 and 240-257.
Galbraith, "Automated Detection of Wafer Surface Defects by Laser Scanning", Silicon Processing, ASTM STP 804, Gupta, ed., ASTM (1983) pp. 492-500.
Green, "Overview of Surface Defect Detection Systems", Northern New England Chapter of I.E.S. (1984).
Inspex, Inc., Undated Data Sheets for W1515-2, W1616, W1990, W1996, EX1500, EX1992, Wafer Inspection Systems.
Martin et al., "Optical Scanning of Silicon Wafers For Surface Contaminants", Electro-Optical Systems Design (Sep. 1980) pp. 45-49.
Harris, et al., "Wafer Inspection Automation; Current and Future Needs," Solid State Tech. (Aug. 1983) pp. 199-205.
"SEMs for Semiconductor Inspection and CD Measurements", Solid State Technology (Jun. 1983) pp. 37-38.
Baker, "Semiconductor Wafer Inspection", SPIE vol. 480 Integrated Circuit Metrology II (1984) pp. 14-21.
Gara, "Automatic Microcircuit and Wafer Inspection", Electronics Test pp. 60-70.
Harris et al., "Process Controlled by Automated in-Process Wafer Inspection", SPIE vol. 470 Optical Microlithography III pp. 253-260.

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