| 摘要 |
PURPOSE:To obtain a photomask and a photomask blank which enables formation of a good pattern by a conventional normal exposing method without requiring increase in luminance of a light source even when the wavelength of the exposure light is decreased, by using a compd. of alkali metal element and halogen element for the substrate where a light-shielding film is formed. CONSTITUTION:This blank consists of a transparent substrate 1 and a light- shielding layer 2 formed on the substrate 1. The transparent substrate 1 consists of a compd. of alkali metal or alkaline earth metal and halogen element which has enough transparency for short wavelength light. For example, lithium fluoride, sodium fluoride, potassium chloride, calcium fluoride, and barium fluoride can be used. By this method, even when short wavelength light is used for exposure in the exposing process for photolithography to produce semiconductors, decrease in the effective intensity of exposure light conventionally caused by the strong light absorption of a photomask can be avoided and highly efficient exposure can performed. |
