Patent ID: 11892768

Abstract:
Provided is a reflective mask blank that can reduce the shadowing effect of a reflective mask and form a fine and high-precision absorbent body pattern.The reflective mask blank comprises a substrate, a multi-layer reflective film disposed on the substrate, and an absorbent body film disposed on the multi-layer reflective film, and is characterized in that: the absorbent body film includes, in at least a part thereof, at least one element with a high absorption coefficient, chosen from the group consisting of cobalt (Co) and nickel (Ni), and an element that increases the speed of dry etching; the absorbent body film includes a lower-surface region that includes a surface on the substrate side and an upper-surface region that includes a surface on the side opposite the substrate; and the concentration (atomic percentage) of the element with the high absorption coefficient in the upper-surface region is greater than the concentration (atomic percentage) of the element with the high absorption coefficient in the lower-surface region.