| 摘要 |
PURPOSE:To enable immediate exposure after alignment and prevent the destruction of an alignment pattern on a wafer during exposure by simultaneously aligning X and Y axes due to approaching the alignment pattern on a reticle and a circuit pattern. CONSTITUTION:When light which has the same wave length with exposing light is irradiated from an optical fiber 11, the alignment pattern 13 on a reticle 1 is illuminated through a relay lens 6. The reflected light reaches on a wafer 3 through a reduction projection lens 16, the image of the alignment pattern on the wafer returns again on the same light route and an image is formed on a moving slit 9 by a magnifying lens 8. The difference DELTA between the center 22 of the alignment pattern on the reticle and the center 23 of the alignment pattern on the wafer is sought and if the difference is made zero, the alignment finishes. Since the alignment pattern 13 on the reticle is provided approaching a circuit pattern 15, both the X and the Y directions can be aligned simultaneously and the alignment pattern on the wafer is not exposed during the exposure. |
