| 摘要 |
PURPOSE:To prevent the lowering of yield rate due to having a blackspot type defect and an opaque stuck matter generating when a pattern transfer is performed by a method wherein an exposure is performed on the same part located on the surface of a wafer through two or more of photo masks having no blackspot type common defect. CONSTITUTION:The first and the second photomasks 23 and 28 are operated in the form of one body, and narrow-stripped beams of light 22b and 22c are scanned on the whole surface of the first and the second photomasks 23 and 28 and a wafer 27 by performing a scanning operation in synchronization with the first and the second photomasks 23 and 28 and the wafer 27. Also, the same mask pattern is formed on the first photomask 23 and the second photomask 28, and the positions of mirrors 24, 25 and 29 are set in such a manner that the beam of light passed through the first and the second photomasks 23 and 28 will be image-formed overlapping on the wafer 27. Consequently, as there is a very little possibility for existence of a blackspot type defect and an opaque stuck manner at the same part of the first photomask 23 and the second photomask 28, an almost complete exposure can be performed. |
