Reflective mask blank, reflective mask, method of manufacturing reflective mask blank, and method of manufacturing reflective mask

Abstract

A reflective mask blank containing a substrate, a multilayer reflective film that reflects EUV light, and a phase shift film that shifts a phase of the EUV light, the substrate, the multilayer reflective film, and the phase shift film being arranged in this order. The phase shift film contains a compound containing Ru and Cr, an element ratio between Cr and Ru (Cr:Ru) in the phase shift film is 5:95 to 42:58, and a melting point MP1 of an oxide of the compound and a melting point MP2 of a fluoride or an oxyfluoride of the compound satisfy the following relation (1): 0.625MP1+MP2≤1000  (1).

Dependencies are inferred from the claim text.