Reflective photomask blank and method for manufacturing reflective photomask

A reflective photomask blank to be used as a material of a reflective photomask used in EUV lithography using EUV light as exposure light, the reflective photomask blank comprising:

• a substrate;
• a reflective multilayer film that is formed on one main surface of the substrate and reflects the exposure light;
• a protective film formed in contact with the reflective multilayer film;
• and
• an absorbing film that is formed on the protective film and absorbs the exposure light,
• wherein the protective film is formed using a film containing ruthenium (Ru),
• wherein the absorbing film is formed using a single-layer film containing tantalum (Ta) and nitrogen (N), and has a content of nitrogen of 30 atom % or more and less than 60 atom %, and
• wherein contrast between light reflected from a surface of the protective film and light reflected on a surface of the absorbing film with respect to light having a wavelength of 193 nm to 248 nm is 20% or more.