| 摘要 |
PURPOSE:To compress the data amount and calculating time required for detecting the position of a reference pattern of a plurality of samples by a self teaching system by employing the average value of position coordinates data and as reference coordinates. CONSTITUTION:Two reference patterns 14, 14', 15, 15' are respectively provided on the surface of a substrate 3 of sample 2 and of a chip 4. The coordinates (Xi, Yi) of the position of the reference pattern are obtained for the larger sample number N higher than the prescribed value, and the average value is stored as reference coordinates. Since the reference coordinates approximately coincide with the distribution center of the position of the entire reference pattern, the reference coordinates (Xi, Yi) are specified as the coordinates of the center P of the detecting window 1. The size of the detecting window 1 is set approximately equal to the width of distribution of the coordinates of the position of the reference pattern to reduce the signal amount in the quantity corresponding to the contraction of the area of the window and to also reduce the required calculating time. |
