| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for manufacturing a photomask blank, capable of improving light fastness of a light semi-transmitting film or a light-shielding film containing metal and silicon to exposure light at a wavelength of 200 nm or shorter, and improving a service life of a photomask.SOLUTION: A photomask is manufactured by forming a thin film comprising a material containing molybdenum and silicon on a light-transmitting substrate, then subjecting the thin film to a treatment of increasing the number of SiOmolecules in a surface layer of the thin film to form a layer containing silicon and oxide on the surface layer of the thin film, and patterning the thin film. The above treatment on the thin film is carried out in such a manner that, when a thin film pattern of a photomask manufactured by patterning the treated thin film is continuously irradiated with ArF excimer laser light up to the total dose of 30 kJ/cm, a change amount of the line width of the thin film pattern after the irradiation is 5 nm or less.</p> |
