MASK BLANK AND PHOTO MASK

摘要

[PROBLEMS] To provide a large-size mask and a mask blank for FPD for manufacturing an FPD device appropriate for multi-color wave exposure. [MEANS FOR SOLVING PROBLEMS] A mask blank includes a light shielding film having a lower layer portion having the light shielding function and an upper layer portion having the reflection preventing function formed on a translucent substrate. The light shielding film is controlled so that a fluctuation width of the film surface reflectance is below 1% in a wavelength band at least from i-line to g-line emitted from an ultra high pressure mercury lamp.