Reflective blank photomask and manufacturing method of reflective photomask

Abstract

[Objective] To provide a reflective blank photomask in which the protective film, whether made of rhodium (Rh) or a material containing rhodium (Rh) and ruthenium (Ru), is not easily damaged even when dry etching with oxygen (O) gas is used in the photomask manufacturing process, and to suppress the reduction of the protective film thickness and the oxidation of the protective film, and a method for manufacturing a reflective photomask using the reflective blank photomask. [Solution] The reflective blank photomask (100) is a material used in EUV lithography (110) where EUV light is used as the exposure light. The reflective blank photomask (100) comprises: a substrate (1); a multilayer reflective film (2) formed above a main surface of the substrate (1) to reflect exposure light; a protective film (3) formed on the multilayer reflective film (2) to protect the multilayer reflective film (2); an absorbing film (5) formed above the protective film (3) to absorb exposure light; and an etch stop film (4) disposed between the protective film (3) and the absorbing film (5) and containing niobium (Nb). The protective film (3) has at least one layer containing rhodium (Rh). The layer of the multilayer reflective film (2) in contact with the protective film (3) contains Mo.

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