| 摘要 |
PURPOSE:To perform position alignment at a specified aligning accuracy in a short time, by performing theta alignment of a planar body such as a wafer, which has a suitable pattern on its surface, by an image recognizing device and the like, thereby automating the theta alignment. CONSTITUTION:An (x) stage 1 is moved, and an image, which is taken by a camera 8, is compared with an image, which is stored before, in an image recognizing device. Thus deviating amounts DELTAx1 and DELTAy1 in the directions (x) and (y) are obtained. A deviating amount theta1 between a moving direction 39 of the (x) stage 1 and a scribing line in the direction of the (x) axis of a wafer 4 can be computed based on the deviating amounts DELTAx1 and DELTAy1. When the (x) stage 1 is moved more than a position 34, coordinates X2 and Y2 of the position 37, at which the camera 8 arrives, are computed by using the value of theta1. The (x) and (y) stages are moved to the position 37, and the image taken by the camera 8 is compared with the image stored before, and deviating amounts DELTA2 and DELTAy2 are obtained. When theta1 is a correct value, the camera 8 takes the same image at a position 31, which is stored before, at a position 33. Based on the deviating amounts DELTAx2 and DELTAy2, actual deviating amout theta2 between the moving direction 39 of the (x) stage and the scribing line of the wafer 4 is computed. A chuck 3 is rotated by the computed devaiting amount theta2.
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