| 摘要 |
PURPOSE:To execute a highly accurate alignment operation over the whole region of a semiconductor wafer by a method wherein marks on the wafer side are put not only in the central part but also in the peripheral part on the semiconductor wafer and the semiconductor wafer is aligned with a photomask by using the marks. CONSTITUTION:Two each of marks 11 to 16 which are symmetric are arranged at the upper part, in the central part and at the lower part on a semiconductor wafer 1. As the marks on the wafer side, e.g. the upper-part mark 11 is constituted of two line segments 11a, 11b as slanted lines which are spread in an upward open manner. Four line segments 21a to 21d are put in advance on a photomask with reference to the upper-part mark 11, on the wafer side on the left side, which is composed of the two line segments 11a, 11b. The same is applied to the other marks on the wafer side. A positioning operation is executed by using the central marks 13, 14 on the wafer side and marks on the mask side which correspond to them; after that, an offset value between the corresponding marks on both is decided. In succession, offset values between corresponding marks are decided in the same manner regarding the upper-part marks and the lower-part marks on the wafer side. The position between the semiconductor wafer 1 and the photomask is corrected on the basis of the offset values in the above 6 points; after that, an exposure operation is executed. |
