Nippondenso Co., Ltd.

Takahiro Itakura

Yoshio Yokoyama

Pixels A, B, C, D and E of a reference image X, which are suitable for use in a pattern matching operation, are automatically determined on a pattern of the reference image. The automatic determination of the pixels is done based on a change of brightness at areas around the selected pixels. Coordinates of all of the selected pixels, such as (x.sub.1, y.sub.1), (x.sub.2, y.sub.2), (x.sub.3, y.sub.3), (x.sub.4, y.sub.4) and (x.sub.5, y.sub.5) are stored in memory. A scan of the image to be detected is done at a fixed offset area for each of the selected pixels. The values of the difference in brightness between the selected pixels and the scanned points are accumulated. The minimum value of the accumulated difference is detected, and the coordinate of the scanned point which provides the minimum accumulated difference is determined as a deviation of the detected image from the reference image.

Method and device for measuring the position of a pattern

An inspection device and method that closely approximates a visual inspection technique for evaluating the quality of a sample. A mask image generation section generates a master image from an image signal of a known good sample. The image signal is used to a first mask image. A plurality of second mask images are generated by magnifying a pattern area of the first mask image by different magnification ratios. A discrimination surface area threshold is set for each mask image. An image under inspection generation section generates a binary image of an unknown sample. A discrimination section takes the logical AND of the binary images of the unknown sample and each mask image, calculates surface areas of pinhole flaws existing in a background area of the binary image under inspection, compares the calculated surface areas and the threshold corresponding to the mask images, and performs a pass/fail judgement of the unknown sample based on the result of this comparison.

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Kariya, Japan

Takahiro Itakura