| 摘要 |
PURPOSE:To protect a photomask from pollution and protect light shielding material constituting elements from pollution due to impurities and virulence, by arranging a plate-shaped member separated from a light shielding film so that this member faces a substrate with the light shielding film, which is provided for forming a pattern on a part of the substrate, between themselves and making one of the substrate and the plate-shaped member light-transmissive at least to constitute and photomask. CONSTITUTION:A laser beam 5 is made incident to a photomask blank 12 from the surface of an optical glass 1 on the side opposite to that of formation of a light shielding film 2 on this glass 1, and the light shielding film 2 is worked directly into a desired pattern by a laser describing device to form a reticle pattern. A photomask 12' formed in this manner is set as a reticle of a reduction projecting exposure device in an optically fixed position. The pattern of the photomask 12' passes through a reduction projecting lens 8 to form a reduction pattern on a sample table 9 having a wafer. Since the reticle attained by using the photomask blank 12 is covered with optical materials, the occurrence of a defective pattern on the wafer due to stucking of foreign matters is prevented at this time. |
