Abstract of the Disclosure

A method and apparatus for detecting positions of chips on a semiconductor wafer. The method comprises an illuminating step for illuminating obliquely the semiconductor wafer from above including at least a position detecting direction; a totalizing step for optically totalizing, when the irregular reflecting rays reflecting at the semiconductor wafer illuminated at the illuminating step are photographed by an image pickup element or device, the irregular reflecting rays in the direction normal to the position detecting direction or for electrically totalizing the levels of a video signal produced by the image pickup element or device in the same direction; a video signal detecting step for producing a video signal with coordinates lying in the position detecting direction by photographing an image resulting from optical totalization at the totalizing step by the image pickup element or device or electrically totalizing the image; and a street position detecting step for detecting a street position between chips by extracting a specific coordinate with a wide width and a low level corresponding to dark from the video signal produced at the video signal detecting step. The apparatus executes the above-mentioned method

• a schematic diagram of an embodiment of an apparatus for detecting the positions of chips on a semiconductor wafer according to the invention.

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