System and method for process variation monitor

Data processing: generic control systems or specific application – Specific application – apparatus or process – Product assembly or manufacturing

Reexamination Certificate

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C348S014090, C382S145000

Reexamination Certificate

active

06862491

ABSTRACT:
A method to extend the process monitoring capabilities of a semiconductor wafer optical inspection system so as to be able to detect low-resolution effects of process variations over the surface of a wafer at much higher sensitivity than heretofore possible. The method consists, in essence, of grouping sensed pixels by geometric blocks over the inspected surface and comparing each block with a corresponding one from another die on the same wafer, from another wafer or from a stored model image. In one embodiment of the invention, pixel values are compared directly and differences are thresholded at a considerably lower level than during a defects detection process. In another embodiment, there is calculated a signature for each block, based on the sensed light intensity values, and corresponding signatures are compared.

REFERENCES:
patent: 5909276 (1999-06-01), Kinney et al.
patent: 5991699 (1999-11-01), Kulkarni et al.
patent: 6456899 (2002-09-01), Gleason et al.
patent: 6484306 (2002-11-01), Bokor et al.
patent: 20020165636 (2002-11-01), Hasan
patent: 20030063791 (2003-04-01), Smilansky et al.

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