| 摘要 |
PURPOSE:To precisely detect the position of a mark image, by installing a projection lens system which projects the pattern of a first object on a second object by using exposure light, and a detection means which detects the image of a mark on the second object by using detection light whose wavelength is different from that of the exposure light, and correcting coma aberration generated in the projection lens system. CONSTITUTION:The pattern of a reticle 8 as a first object is projected on a wafer 3 as a second object by a projection lens system 5 with exposure light. The wafer 3 is illuminated with detection light whose wavelength is different from that of the exposure light. The detection light reflected from the wafer is received via the projection lens system 5, and the image of a mark 4 on the wafer 3 is detected by using a detection means 101. A part of a lens group 13 constituting the detection means 101 is deviated from the optical axis of the detection means 101, and the coma aberration generated in the projection lens system 5 is corrected. Thereby the position of a mark image can be precisely detected when the mark is detected with the detection light whose wavelength is different from that of the exposure light, so that highly precise alignment can be realized. |
