# US 10,481,484 B2 · Reflective mask blank, reflective mask, method for manufacturing reflective mask blank, and method for manufacturing semiconductor device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,481,484 B2 - Document ID: US10481484B2 - Status: Granted - Kind: B2 - Application number: 15/829,090 - Filed: 2017-12-01 - Published: 2018-05-03 - Granted: 2019-11-19 - Earliest claimed: 2013-12-25 - Assignees: Hoya Corporation - Applicants: Hoya Corporation - Inventors: Yohei Ikebe; Takahiro Onoue; Tsutomu Shoki - Web page: https://patentgrep.com/patent/US10481484B2 ## CPC - G03F 1/24: Reflection masks; Preparation thereof - G03F 1/26: Phase shift masks [PSM]; PSM blanks; Preparation thereof - G03F 1/38: Masks having auxiliary features, e.g. special coatings or marks for alignment or testing; Preparation thereof - G03F 1/48: Protective coatings - G03F 7/2004: {characterised by the use of a particular light source, e.g. fluorescent lamps or deep UV light} - C23C 14/0641: {Nitrides (C23C14/0617 takes precedence)} - C23C 14/185: {by cathodic sputtering} - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) ## Abstract A reflective mask blank that comprises a multilayer reflective film 13, protective film 14, and phase-shift film 16 for shifting a phase of the EUV light, which are formed in said order on a substrate 12. The protective film 14 is made of a material containing ruthenium as a main component, and an anti-diffusion layer 15 which is an oxidized layer containing ruthenium as a main component is formed on a surface of the protective film 14, or as a part of the protective film 14 on a side adjacent to the phase-shift layer 16, so as to inhibit counter diffusion in relation to the phase-shift film 16, thereby inhibiting the thermal diffusion between the protective film 14 and the material of the phase-shift film pattern. Also, a reflective mask and method of manufacture. ## Claims ### Claim 1 A reflective mask blank comprising: a substrate, and a multilayer reflective film, a protective film, and a phase-shift film for shifting a phase of EUV light, which are formed in said order on the substrate, wherein the protective film is made of a material containing ruthenium as a main component, and wherein an anti-diffusion layer which contains ruthenium and oxygen is formed on a surface of the protective film, or as a part of the protective film on a side adjacent to the phase-shift film, so as to inhibit counter diffusion in relation to the phase-shift film. ### Claim 2 (depends on 1) The reflective mask blank according to claim 1, wherein the phase-shift film has a material layer which is etchable with a chlorine-based gas or a fluorine-based gas, and wherein the material layer is adjacent to the anti-diffusion layer. ### Claim 3 (depends on 1) The reflective mask blank according to claim 1, wherein a thickness of the anti-diffusion layer is not less than 0.2 nm and not more than 1.5 nm. ### Claim 4 (depends on 1) The reflective mask blank according to claim 1, wherein a ratio of oxygen to ruthenium in the anti-diffusion layer is not less than 0.8 and not more than 2.2. ### Claim 5 (depends on 1) The reflective mask blank according to claim 1, wherein the phase-shift film is formed in a laminated structure, and has a chromium-based material layer as an outermost surface layer. ### Claim 6 (depends on 5) The reflective mask blank according to claim 5, wherein the chromium-based material layer comprises carbon. ### Claim 7 (depends on 1) The reflective mask blank according to claim 1, wherein the phase-shift film is formed in a laminated structure, and has a ruthenium-based material layer as an outermost surface layer. ### Claim 8 (depends on 1) The reflective mask blank according to claim 1, wherein an etching mask film is formed on the phase-shift film. ### Claim 9 (depends on 1) The reflective mask blank according to claim 1, wherein an uppermost layer of the multilayer reflective film is silicon (Si), and a silicon oxide layer comprising silicon and oxygen is provided between the uppermost layer and the protective film. ### Claim 10 (depends on 1) A method for manufacturing a reflective mask blank, comprising forming the phase-shift film in the reflective mask blank according to claim 1 by a sputtering method, continuously without exposure to the atmosphere from the beginning to the end of film formation. ### Claim 11 (depends on 1) The reflective mask blank according to claim 1, wherein the protective film is made of a material which is a Ru metal simple substance; a Ru alloy containing Ru and at least one metal selected from Nb, Zr, Y, B, Ti, La, Mo, Co, and Re; a Ru metal simple substance containing nitrogen; or a Ru alloy containing Ru, nitrogen, and at least one metal selected from Nb, Zr, Y, B, Ti, La, Mo, Co, and Re. ### Claim 12 (depends on 1) The reflective mask blank according to claim 1, wherein the anti-diffusion layer contains N or H. ### Claim 13 A reflective mask comprising: a substrate, and a multilayer reflective film, a protective film, and a phase-shift film pattern for shifting a phase of EUV light, which are formed in said order on the substrate, wherein the protective film is made of a material containing ruthenium as a main component, and wherein an anti-diffusion layer which contains ruthenium and oxygen is formed on a surface of the protective film, or as a part of the protective film on a side adjacent to the phase-shift film pattern, so as to inhibit counter diffusion in relation to the phase-shift film pattern. ### Claim 14 (depends on 13) The reflective mask according to claim 13, wherein a thickness of the anti-diffusion layer is not less than 0.2 nm and not more than 1.5 nm. ### Claim 15 (depends on 13) The reflective mask according to claim 13, wherein a ratio of oxygen to ruthenium in the anti-diffusion layer is not less than 0.8 and not more than 2.2. ### Claim 16 (depends on 13) The reflective mask according to claim 13, wherein the phase-shift film pattern is formed in a laminated structure, and has a ruthenium-based material layer as an outermost surface layer. ### Claim 17 (depends on 13) The reflective mask according to claim 13, wherein the protective film is made of a material which is a Ru metal simple substance; a Ru alloy containing Ru and at least one metal selected from Nb, Zr, Y, B, Ti, La, Mo, Co, and Re; a Ru metal simple substance containing nitrogen; or a Ru alloy containing Ru, nitrogen, and at least one metal selected from Nb, Zr, Y, B, Ti, La, Mo, Co, and Re. ### Claim 18 (depends on 13) The reflective mask according to claim 13, wherein the anti-diffusion layer contains N or H. ### Claim 19 A method for manufacturing a semiconductor device, comprising: setting a reflective mask in an exposure apparatus having an exposure light source for emitting EUV light, so as to transfer a transfer pattern onto a resist film formed on a transfer target substrate, wherein the reflective mask comprises: a substrate, and a multilayer reflective film, a protective film, and a phase-shift film pattern for shifting a phase of EUV light, which are formed in said order on the substrate, wherein the protective film is made of a material containing ruthenium as a main component, and wherein an anti-diffusion layer which contains ruthenium and oxygen is formed on a surface of the protective film, or as a part of the protective film on a side adjacent to the phase-shift film pattern, so as to inhibit counter diffusion in relation to the phase-shift film pattern. ### Claim 20 (depends on 19) The method for manufacturing a semiconductor device according to claim 19, wherein an electric power consumption of the exposure light source is 80 W or more.