| 摘要 |
SOLUTION: A binary photomask blank is provided, which includes a light-shielding film on a transparent substrate, the light-shielding film containing a transition metal M and silicon Si, or a transition metal M, silicon Si and nitrogen N, as essential components, comprising a single layer or a plurality of layers, and having an optical density of 3.0 or more. The light-shielding film includes a layer satisfying B≤0.68×A+0.23 with regard to the composition of the transition metal, silicon and nitrogen, where A represents an atomic ratio of M relative to Si and B represents an atomic ratio of N relative to Si, and has a film thickness of 47 nm or less.EFFECT: The binary photomask blank of the present invention has a thinner light-shielding film that can sufficiently shields against exposure light. When the binary photomask blank is processed into a photomask, a resist film having a reduced film thickness can be used and thereby, a binary photomask with higher accuracy can be obtained.SELECTED DRAWING: Figure 5 |
