Abstract: Provided are an EUV mask blank in which deterioration in reflectivity due to oxidation of a Ru protective layer is prevented, a reflective layer-equipped substrate to be used for producing the EUV mask blank, and a process for producing the reflective layer-equipped substrate. A reflective layer-equipped substrate for EUV lithography comprising a substrate, and a reflective layer for reflecting EUV light and a protective layer for protecting the reflective layer, formed in this order on the substrate, wherein the reflective layer is a Mo/Si multilayer reflective film, the protective layer is a Ru layer or a Ru compound layer, and an intermediate layer containing from 0.5 to 25 at % of nitrogen and from 75 to 99.5 at % of Si is formed between the reflective layer and the protective layer.

Abstract: Provided are a multilayer mirror for EUVL in which deterioration in reflectivity due to oxidation of a Ru protective layer is prevented, and a process for its production. A multilayer mirror for EUV lithography comprising a substrate, and a reflective layer for reflecting EUV light and a protective layer for protecting the reflective layer, formed in this order on the substrate, wherein the reflective layer is a Mo/Si multilayer reflective film, the protective layer is a Ru layer or a Ru compound layer, and an intermediate layer containing from 0.5 to 25 at % of nitrogen and from 75 to 99.5 at % of Si is formed between the reflective layer and the protective layer.

Abstract: Provided are an EUV mask blank in which deterioration in reflectivity due to oxidation of a Ru protective layer is prevented, a reflective layer-equipped substrate to be used for producing the EUV mask blank, and a process for producing the reflective layer-equipped substrate. A reflective layer-equipped substrate for EUV lithography comprising a substrate, and a reflective layer for reflecting EUV light and a protective layer for protecting the reflective layer, formed in this order on the substrate, wherein the reflective layer is a Mo/Si multilayer reflective film, the protective layer is a Ru layer or a Ru compound layer, and an intermediate layer containing from 0.5 to 25 at % of nitrogen and from 75 to 99.5 at % of Si is formed between the reflective layer and the protective layer.

Abstract: Provided are a multilayer mirror for EUVL in which deterioration in reflectivity due to oxidation of a Ru protective layer is prevented, and a process for its production. A multilayer mirror for EUV lithography comprising a substrate, and a reflective layer for reflecting EUV light and a protective layer for protecting the reflective layer, formed in this order on the substrate, wherein the reflective layer is a Mo/Si multilayer reflective film, the protective layer is a Ru layer or a Ru compound layer, and an intermediate layer containing from 0.5 to 25 at % of nitrogen and from 75 to 99.5 at % of Si is formed between the reflective layer and the protective layer.

Abstract: An apparatus for polishing an edge surface of a glass substrate for magnetic recording media. The apparatus includes a grindstone including abrasive grains mixed with a resin. The grindstone is configured to polish at least the edge surface of the glass substrate. The grindstone has a reentrant groove with a bottom surface and sidewall surfaces such that the bottom surface of the reentrant groove contacts the edge surface of the glass substrate and the sidewall surfaces of the reentrant groove contacts chamfered sidewalls of the glass substrate. The reentrant groove and sidewall surfaces are formed in the resin of the grindstone by pressing the glass substrate into the resin of the grindstone with a force higher than a pressing force during polishing.

Abstract: An apparatus for polishing an edge surface of a glass substrate for magnetic recording media. The apparatus includes a grindstone including abrasive grains mixed with a resin. The grindstone is configured to polish at least the edge surface of the glass substrate. The grindstone has a reentrant groove with a bottom surface and sidewall surfaces such that the bottom surface of the reentrant groove contacts the edge surface of the glass substrate and the sidewall surfaces of the reentrant groove contacts chamfered sidewalls of the glass substrate.

Abstract: To provide an apparatus for polishing an edge surface of a glass substrate for magnetic recording media and a process for producing a glass substrate for magnetic recording media, whereby with respect to a glass substrate to be used as a substrate for a hard disk, the quality and productivity can be improved without requiring extra effort. In a process for practically producing a hard disk by using a glass substrate 2, the arithmetic average roughness (Ra) required for the outer edge surface of the glass substrate is at most 100 nm. With the roughness of this level, highly productive mechanical polishing by a grindstone is possible. Further, since such mechanical polishing is possible, the productivity can be increased by adopting sheet treatment. Further, by stabilizing the processing margin by employing a grindstone 4 made of resin, variations in the dimensional precision in the individual glass substrates can be minimized.