Patent ID: 11934093

Abstract:
A reflective mask blank for EUV lithography, includes: a substrate; a conductive film; a reflective layer; and an absorption layer, the absorption layer absorbing the EUV light, wherein the conductive film has a refractive index nλ1000-1100 nm of 5.300 or less and has an extinction coefficient kλ1000-1100 nm of 5.200 or less, at a wavelength of 1000 nm to 1100 nm, the conductive film has a refractive index nλ600-700 nm of 4.300 or less and has an extinction coefficient kλ600-700 nm of 4.500 or less, at a wavelength of 600 nm to 700 nm, the conductive film has a refractive index nλ400-500 nm of 2.500 or more and has an extinction coefficient kλ400-500 nm of 0.440 or more, at a wavelength of 400 nm to 500 nm, and the conductive film has a film thickness t of 40 nm to 350 nm.