SUBSTRATE WITH MULTILAYER REFLECTIVE FILM, REFLECTIVE MASK BLANK FOR EUV LITHOGRAPHY, METHOD FOR PRODUCING REFLECTIVE MASK FOR EUV LITHOGRAPHY, AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

The purpose of the present invention is to provide: a substrate with a multilayer reflective film, which is used for the production of a reflective mask blank for EUV lithography wherein dry etching using a Cl-based gas is carried out, and which is extremely reduced in the loss of a protective film due to the above-mentioned dry etching and wet cleaning after the dry etching; and the like. The present invention is a substrate with a multilayer reflective film, which is used for the production of a reflective mask blank for EUV lithography, and which is characterized in that: the substrate with a multilayer reflective film comprises a substrate, a multilayer reflective film that is formed on the substrate and reflects EUV light, and a protective film that is formed on the multilayer reflective film and protects the multilayer reflective film; the protective film is formed of an alloy that contains at least two kinds of metals; and the alloy is a complete solid solution.