PHOTOMASK BLANK, PHOTOMASK AND METHOD FOR MANUFACTURING THE PHOTOMASK

摘要

Provided is a photomask blank to be used for manufacturing a photomask (100) to which exposure light with a wavelength of 200 nm or less is to be applied.  The photomask blank is provided with a light transmitting substrate (1), and a light blocking film (10) formed on the light transmitting substrate.  The light blocking film has a light blocking layer (12), which contains a transition metal and silicon, and a surface reflection preventing layer (13), which is formed on the light blocking layer in contact with the light blocking layer and is composed of a material containing oxygen and/or nitrogen.  In the case where the surface reflectivity to the exposure light is a predetermined value or less and the film thickness of the surface reflection preventing layer fluctuates within the range of 2 nm, the light blocking film has characteristics of controlling the surface reflectivity such that the fluctuation range with the exposure wavelength is within 2%.  A surface reflection preventing layer material having a refraction index (n) and an extinction coefficient (k) that give such characteristics is selected.