| 摘要 |
PURPOSE:To enable to measure superposing precision with high precision, and to enable to measure in regard to places of a large number on a wafer in a short time by a method wherein superposing precision is measured using the mark detection method. CONSTITUTION:The detect the positions of chip marks 20-23, heights Z in the neighborhood of the position detecting chip marks are measured, the deflection distortion correcting coefficients C, D at the heights Z thereof are calculated by a controlling computer 130, and the results thereof are set in a deflection distortion correcting arithmetic circuit 144. Beam deflected position data Xm, Ym for detection of position are stored in a memory unit 145. When the positions are to be detected, by changing over change-over switches 143, 172, operations are performed for data Xm, Ym at the deflection distortion correcting arithmetic circuit 144, and a beam deflector 101 is driven according to the result thereof. As a result, a beam is deflected to the prescribed position on a coordinate system constructed by a laser measuring machine. Accordingly, the positions of the respective chip marks 20-23 are detected, and the coefficients of a chip distortion correction formula are calculated from the result thereof. The calculated coefficients are set in a chip distortion correcting arithmetic circuit 142. |
