| 摘要 |
PURPOSE:To detect and correct the deviation of position with high accuracy by detecting diffracted light beams by a 2nd one-dimensional linear diffraction grating so that the incident angle of the light beam may be detected, correcting the deviation of position and transferring a mask pattern on a wafer. CONSTITUTION:The incident angle of the light beam 21 onto a linear Fresnel zone plate 23 formed on a mask 22 is scanned. Therefore, a slit image 27 formed on the wafer 25 by the linear Fresnel zone plate 23 is moved. When the slit image 27 is superposed on a 1st one-dimensional linear diffraction grating 26 formed on the wafer 25 and the diffracted light beams by the diffraction grating 26 is detected, the deviation of position between the mask 22 and the wafer 25 is detected from the incident angle of the light 21. The diffracted light beams by the 2nd one-dimensional linear diffraction gratings 24a and 24b are detected and the incident angle of the light 21 is detected. After correcting the deviation of position, the mask pattern is transferred on the wafer. |
