A reflective mask blank includes a substrate; a multilayer reflective film that reflects EUV light; a protection film that protects the multilayer reflective film; and a phase shift film that shifts a phase of the EUV light, the substrate, the multilayer reflective film, the protection film, and the phase shift film being arranged in this order.
The phase shift film contains at least one first element X1 selected from the first group consisting of ruthenium (Ru), iridium (Ir), platinum (Pt), palladium (Pd), and gold (Au), and at least one second element X2 selected from the second group consisting of oxygen (O), boron (B), carbon (C), and nitrogen (N). In the phase shift film, a chemical shift of a peak of 3d5/2 or a peak of 4f7/2 of the first element X1 observed by X-ray electron spectroscopy is less than 0.3 eV.