# US 10,481,485 B2 ยท Mask blank, transfer mask, method of manufacturing transfer mask and method of manufacturing semiconductor device > Agents: this data is available as JSON from the patentgrep API and MCP server โ€” see https://patentgrep.com/llms.txt - Number: US 10,481,485 B2 - Document ID: US10481485B2 - Status: Granted - Kind: B2 - Application number: 15/571,131 - Filed: 2016-05-10 - Published: 2018-09-13 - Granted: 2019-11-19 - Earliest claimed: 2015-05-15 - Assignees: Hoya Corporation - Applicants: Hoya Corporation - Inventors: Osamu Nozawa; Takenori Kajiwara; Ryo Ohkubo - Web page: https://patentgrep.com/patent/US10481485B2 ## CPC - G03F 1/32: Attenuating PSM [att-PSM], e.g. halftone PSM or PSM having semi-transparent phase shift portion,; Preparation thereof - G03F 1/50: Mask blanks not covered by G03F1/20 - G03F1/34; Preparation thereof - G03F 1/54: Absorbers, e.g. of opaque materials - G03F 1/74: by charged particle beam [CPB], e.g. focused ion beam - G03F 1/78: by charged particle beam [CPB], e.g. electron beam patterning of masks - G03F 1/80: Etching - 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) ## Abstract A mask blank comprising an etching stopper film. The mask blank comprises a thin film for pattern formation on a main surface of a transparent substrate, and is featured in that: the thin film for pattern formation contains silicon, an etching stopper film is provided between the transparent substrate and the thin film for pattern formation, and the etching stopper film contains silicon, aluminum, and oxygen. ## Claims ### Claim 1 A mask blank comprising: a transparent substrate; a thin film for pattern formation provided on a main surface of the transparent substrate; an etching stopper film provided between the transparent substrate and the thin film for pattern formation, wherein the thin film for pattern formation contains silicon; wherein the etching stopper film is single layered film; and wherein the etching stopper film contains silicon, aluminum, and oxygen. ### Claim 2 (depends on 1) The mask blank according to claim 1, wherein the oxygen content of the etching stopper is 60 atom % or more. ### Claim 3 (depends on 1) The mask blank according to claim 1, wherein the ratio of the silicon content to the total content of silicon and aluminum in the etching stopper film is โ…˜ or less in terms of atom %. ### Claim 4 (depends on 1) The mask blank according to claim 1, wherein the etching stopper film consists essentially of silicon, aluminum, and oxygen. ### Claim 5 (depends on 1) The mask blank according to claim 1, wherein the etching stopper film is formed in contact with the main surface of the transparent substrate. ### Claim 6 (depends on 1) The mask blank according to claim 1, wherein the etching stopper film has a thickness of 3 nm or more. ### Claim 7 (depends on 1) The mask blank according to claim 1, wherein the thin film for pattern formation contains silicon and nitrogen. ### Claim 8 (depends on 1) The mask blank according to claim 1, wherein the thin film for pattern formation contains a transition metal, silicon, and nitrogen. ### Claim 9 (depends on 1) The mask blank according to claim 1, wherein the thin film for pattern formation is a phase shift film. ### Claim 10 (depends on 9) The mask blank according to claim 9, wherein the phase shift film has a function to transmit exposure light at a transmittance of 1% or more, and a function to cause a phase difference of not less than 150 and not more than 180 degrees between the exposure light having transmitted through the phase shift film and the exposure light having passed through air for the same distance as the thickness of the phase shift film. ### Claim 11 (depends on 9) The mask blank according to claim 9, wherein the mask blank includes a light shielding film on the phase shift film. ### Claim 12 (depends on 1) The mask blank according to claim 1, wherein the etching stopper film has the difference in content of each constituent element in the thickness direction is within 5 atom %. ### Claim 13 (depends on 1) The mask blank according to claim 1, wherein the etching stopper film has an amorphous structure in a state including a bond of silicon and oxygen and a bond of aluminum and oxygen. ### Claim 14 (depends on 1) The mask blank according to claim 1, the etching stopper film is made of materials combined Al2O3 and SiO2. ### Claim 15 A transfer mask comprising: a transparent substrate; a thin film, having a pattern, provided on a main surface of the transparent substrate; an etching stopper film provided between the transparent substrate and the thin film for pattern formation, wherein the thin film for pattern formation contains silicon; wherein the etching stopper film is single layered film; and wherein the etching stopper film contains silicon, aluminum, and oxygen. ### Claim 16 (depends on 15) The transfer mask according to claim 15, wherein the oxygen content of the etching stopper is 60 atom % or more. ### Claim 17 (depends on 15) The transfer mask according to claim 15, wherein the ratio of the silicon content to the total content of silicon and aluminum in the etching stopper film is โ…˜ or less in terms of atom %. ### Claim 18 (depends on 15) The transfer mask according to claim 15, wherein the etching stopper film consists essentially of silicon, aluminum, and oxygen. ### Claim 19 (depends on 15) The transfer mask according to claim 15, wherein the etching stopper film is formed in contact with the main surface of the transparent substrate. ### Claim 20 (depends on 15) The transfer mask according to claim 15, wherein the etching stopper film has a thickness of 3 nm or more. ### Claim 21 (depends on 15) The transfer mask according to claim 15, wherein the thin film contains silicon and nitrogen. ### Claim 22 (depends on 15) The transfer mask according to claim 15, wherein the thin film contains a transition metal, silicon, and nitrogen. ### Claim 23 (depends on 15) The transfer mask according to claim 15, wherein the thin film is a phase shift film. ### Claim 24 (depends on 15) The transfer mask according to claim 15, wherein the phase shift film has a function to transmit exposure light at a transmittance of 1% or more, and a function to cause a phase difference of not less than 150 and not more than 180 degrees between the exposure light having transmitted through the phase shift film and the exposure light having passed through air for the same distance as the thickness of the phase shift film. ### Claim 25 (depends on 15) The transfer mask according to claim 15, wherein the etching stopper film has the difference in content of each constituent element in the thickness direction is within 5 atom %. ### Claim 26 (depends on 15) The transfer mask according to claim 15, wherein the etching stopper film has an amorphous structure in a state including a bond of silicon and oxygen and a bond of aluminum and oxygen. ### Claim 27 (depends on 15) The transfer mask according to claim 15, the etching stopper film is made of materials combined Al2O3 and SiO2. ### Claim 28 (depends on 23) The transfer mask according to claim 23, wherein the mask blank includes a light shielding film, having a pattern including a light shielding band, on the phase shift film. ### Claim 29 A method of manufacturing a semiconductor device, including: transferring by exposure a transfer pattern to a resist film on a semiconductor substrate using a transfer mask comprising: a transparent substrate; a thin film, having a pattern, provided on a main surface of the transparent substrate; an etching stopper film provided between the transparent substrate and the thin film for pattern formation, wherein the thin film for pattern formation contains silicon; wherein the etching stopper film is single layered film; and wherein the etching stopper film contains silicon, aluminum, and oxygen.