WO2010074125A1 - 反射型マスクブランク及び反射型マスクの製造方法 - Google Patents
反射型マスクブランク及び反射型マスクの製造方法 Download PDFInfo
- Publication number
- WO2010074125A1 WO2010074125A1 PCT/JP2009/071397 JP2009071397W WO2010074125A1 WO 2010074125 A1 WO2010074125 A1 WO 2010074125A1 JP 2009071397 W JP2009071397 W JP 2009071397W WO 2010074125 A1 WO2010074125 A1 WO 2010074125A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- film
- reflective mask
- pattern
- absorber
- absorber film
- Prior art date
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 239000006096 absorbing agent Substances 0.000 claims abstract description 151
- 238000007689 inspection Methods 0.000 claims abstract description 112
- 239000000463 material Substances 0.000 claims abstract description 87
- 239000000758 substrate Substances 0.000 claims abstract description 46
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 33
- 150000004767 nitrides Chemical class 0.000 claims abstract description 29
- 238000012546 transfer Methods 0.000 claims abstract description 29
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 19
- 150000001875 compounds Chemical class 0.000 claims abstract description 16
- KJTLSVCANCCWHF-UHFFFAOYSA-N Ruthenium Chemical compound [Ru] KJTLSVCANCCWHF-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052707 ruthenium Inorganic materials 0.000 claims abstract description 15
- 230000001681 protective effect Effects 0.000 claims description 54
- 239000011651 chromium Substances 0.000 claims description 52
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 32
- 229910052715 tantalum Inorganic materials 0.000 claims description 29
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims description 17
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 16
- 239000010703 silicon Substances 0.000 claims description 16
- 239000010955 niobium Substances 0.000 claims description 6
- 150000003304 ruthenium compounds Chemical class 0.000 claims description 3
- 229910052758 niobium Inorganic materials 0.000 claims description 2
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims description 2
- 239000002075 main ingredient Substances 0.000 abstract 2
- 239000010408 film Substances 0.000 description 377
- 239000010410 layer Substances 0.000 description 103
- 238000005530 etching Methods 0.000 description 27
- 239000007789 gas Substances 0.000 description 27
- 238000002310 reflectometry Methods 0.000 description 23
- 238000000034 method Methods 0.000 description 19
- 229910052760 oxygen Inorganic materials 0.000 description 16
- 229910052796 boron Inorganic materials 0.000 description 15
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 13
- 238000012790 confirmation Methods 0.000 description 13
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 12
- 238000001312 dry etching Methods 0.000 description 12
- 229910052757 nitrogen Inorganic materials 0.000 description 12
- 239000001301 oxygen Substances 0.000 description 12
- 239000004065 semiconductor Substances 0.000 description 12
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 11
- 239000000460 chlorine Substances 0.000 description 11
- 229910052801 chlorine Inorganic materials 0.000 description 11
- 230000007547 defect Effects 0.000 description 11
- 230000000737 periodic effect Effects 0.000 description 11
- 238000013461 design Methods 0.000 description 10
- 239000000203 mixture Substances 0.000 description 10
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 230000000694 effects Effects 0.000 description 8
- 238000002834 transmittance Methods 0.000 description 8
- 239000011521 glass Substances 0.000 description 7
- 230000003287 optical effect Effects 0.000 description 7
- 230000010363 phase shift Effects 0.000 description 6
- 238000004544 sputter deposition Methods 0.000 description 6
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 5
- 229910052731 fluorine Inorganic materials 0.000 description 5
- 239000011737 fluorine Substances 0.000 description 5
- 238000001755 magnetron sputter deposition Methods 0.000 description 5
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 4
- 238000000151 deposition Methods 0.000 description 4
- 238000010894 electron beam technology Methods 0.000 description 4
- 238000001659 ion-beam spectroscopy Methods 0.000 description 4
- 229910052814 silicon oxide Inorganic materials 0.000 description 4
- 239000002210 silicon-based material Substances 0.000 description 4
- 239000010409 thin film Substances 0.000 description 4
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 229910004298 SiO 2 Inorganic materials 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 238000001900 extreme ultraviolet lithography Methods 0.000 description 3
- 239000012528 membrane Substances 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 229910004535 TaBN Inorganic materials 0.000 description 2
- 229910010413 TiO 2 Inorganic materials 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 238000012937 correction Methods 0.000 description 2
- 229910052732 germanium Inorganic materials 0.000 description 2
- 230000031700 light absorption Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 230000007261 regionalization Effects 0.000 description 2
- 229910001374 Invar Inorganic materials 0.000 description 1
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- CXOWYMLTGOFURZ-UHFFFAOYSA-N azanylidynechromium Chemical compound [Cr]#N CXOWYMLTGOFURZ-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000007687 exposure technique Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 229910003465 moissanite Inorganic materials 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 229910000484 niobium oxide Inorganic materials 0.000 description 1
- URLJKFSTXLNXLG-UHFFFAOYSA-N niobium(5+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Nb+5].[Nb+5] URLJKFSTXLNXLG-UHFFFAOYSA-N 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000001552 radio frequency sputter deposition Methods 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 150000003377 silicon compounds Chemical class 0.000 description 1
- 238000005477 sputtering target Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910000500 β-quartz Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/027—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34
- H01L21/033—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising inorganic layers
- H01L21/0334—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising inorganic layers characterised by their size, orientation, disposition, behaviour, shape, in horizontal or vertical plane
- H01L21/0337—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising inorganic layers characterised by their size, orientation, disposition, behaviour, shape, in horizontal or vertical plane characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- 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
- G03F1/00—Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles therefor; Containers specially adapted therefor; Preparation thereof
- G03F1/22—Masks or mask blanks for imaging by radiation of 100nm or shorter wavelength, e.g. X-ray masks, extreme ultraviolet [EUV] masks; Preparation thereof
- G03F1/24—Reflection masks; Preparation thereof
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- 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
- G03F1/00—Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles therefor; Containers specially adapted therefor; Preparation thereof
- G03F1/22—Masks or mask blanks for imaging by radiation of 100nm or shorter wavelength, e.g. X-ray masks, extreme ultraviolet [EUV] masks; Preparation thereof
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- 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
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/20—Exposure; Apparatus therefor
- G03F7/2002—Exposure; Apparatus therefor with visible light or UV light, through an original having an opaque pattern on a transparent support, e.g. film printing, projection printing; by reflection of visible or UV light from an original such as a printed image
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- 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
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/20—Exposure; Apparatus therefor
- G03F7/2002—Exposure; Apparatus therefor with visible light or UV light, through an original having an opaque pattern on a transparent support, e.g. film printing, projection printing; by reflection of visible or UV light from an original such as a printed image
- G03F7/2008—Exposure; Apparatus therefor with visible light or UV light, through an original having an opaque pattern on a transparent support, e.g. film printing, projection printing; by reflection of visible or UV light from an original such as a printed image characterised by the reflectors, diffusers, light or heat filtering means or anti-reflective means used
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/027—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34
- H01L21/0271—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers
- H01L21/0273—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers characterised by the treatment of photoresist layers
- H01L21/0274—Photolithographic processes
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- 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
- G03F1/00—Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles therefor; Containers specially adapted therefor; Preparation thereof
- G03F1/68—Preparation processes not covered by groups G03F1/20 - G03F1/50
Definitions
- the present invention relates to a reflective mask for exposure used for manufacturing semiconductor devices and the like, and a reflective mask blank which is an original for manufacturing the mask.
- EUV lithography which is an exposure technique using extreme ultraviolet (Extreme Ultra Violet: hereinafter referred to as EUV) light with a shorter wavelength
- EUV light refers to light in the wavelength band of the soft X-ray region or the vacuum ultraviolet region, and specifically refers to light having a wavelength of about 0.2 to 100 nm.
- an exposure reflective mask described in Patent Document 1 below has been proposed.
- a multilayer reflective film that reflects exposure light is formed on a substrate, a buffer film is formed on the multilayer reflective film, and an absorber film that absorbs exposure light is formed thereon in a pattern.
- the buffer film is provided between the multilayer reflective film and the absorber film for the purpose of protecting the multilayer reflective film in the pattern forming process and the correcting process of the absorber film.
- Light incident on a reflective mask mounted on an exposure machine (pattern transfer device) is absorbed in a part where the absorber film is present, and a light image reflected by the multilayer reflective film is reflected in a part where there is no absorber film. And transferred onto the semiconductor substrate.
- Such a reflective mask is manufactured by the following process, for example.
- a predetermined resist pattern is formed on the upper surface of a reflective mask blank in which a multilayer reflective film, a buffer film, and an absorber film are sequentially formed on a substrate, and dry etching is performed using the resist pattern as an etching mask.
- a predetermined pattern is formed on the absorber film.
- the inspection light is used to inspect whether the pattern is formed on the absorber film as designed. At this time, the inspection light reflected by the absorber film and the inspection light reflected by the buffer film exposed by removing the absorber film are detected, and the inspection is performed by observing the contrast.
- the absorber film pattern has white defects or black defects
- the white defects are repaired by pinholes etc. by the FIB assist deposition method, etc.
- the portion is corrected by removing unnecessary portions by FIB irradiation or the like.
- the buffer film is removed according to the absorber film pattern by dry etching, and the pattern is transferred to the buffer film.
- a final confirmation inspection of the formed pattern is performed using inspection light. At this time, inspection is performed by detecting inspection light reflected by the absorber film and inspection light reflected by the multilayer reflection film exposed by removing the absorber film and the buffer film, and observing the contrast. .
- JP-A-8-213303 Japanese Patent No. 3806702 JP 2004-207593 A
- the inspection light reflected by the absorber film and the buffer film exposed by removing the absorber film are reflected.
- the final confirmation inspection is performed after transferring the absorber film pattern to the buffer film, the inspection light reflected by the absorber film, the absorber film, Since the inspection is performed by observing the contrast with the inspection light reflected by the exposed multilayer reflection film after the buffer film is removed, sufficient contrast is obtained between the absorber film and the buffer film or the multilayer reflection film. Otherwise, accurate pattern inspection cannot be performed.
- the absorber layer has a laminated structure in which an absorber layer for exposure light such as EUV light is a lower layer and a low reflection layer for inspection light is an upper layer, thereby improving the contrast and improving the accuracy. Reflective mask blanks that can perform simple pattern inspection are described.
- the multilayer reflective film is a multilayer film in which elements having different refractive indexes are periodically stacked.
- a thin film of a heavy element or a compound thereof and a thin film of a light element or a compound thereof are alternately 40 to 60.
- a multi-layered film having a period is used.
- a Mo / Si periodic laminated film in which Mo films and Si films are alternately laminated for about 40 cycles is preferably used.
- Mo is easily oxidized when exposed to the atmosphere, and the reflectivity is reduced.
- the outermost layer is a Si film and the film thickness is lower than that of the lower Si film. It was formed thick and functioned as a protective film. That is, it can be said that the contrast with respect to the inspection light has been adjusted so as to be substantially secured between the absorber film, the protective film, and the buffer film (when the buffer film is provided).
- a thick Si film is formed as a protective film on the multilayer reflective film, there is a problem that the reflectance of EUV light is lowered.
- the outermost layer of the multilayer reflective film is a Si film having the same thickness as the lower layer of the same material, and a protective film made of a material mainly composed of Ru is provided on the upper surface. I'm starting. In this case, the contrast with respect to the inspection light must be considered with a protective film containing Ru as a main component.
- the upper low reflection layer for example, a material containing Ta, B, and O is used.
- a material containing Ta, B, and O is usually used as the inspection light used for the above-described pattern inspection.
- the wavelength is about 257 nm. It is possible to adjust so that the reflectance with respect to the inspection light is minimized.
- inspection light having a shorter wavelength than conventional ones for example, ArF excimer laser (wavelength 193 nm) and F2 excimer laser (wavelength 157 nm). Has occurred.
- the reflectivity with respect to the inspection light having a wavelength of 200 nm or less is very high, so that the contrast can be ensured to some extent even if the reflectivity of the absorber film is high.
- the reflectivity for the inspection light with a wavelength of 200 nm or less is not as high as in the case of Si. There is a problem that it is difficult to ensure contrast.
- the thickness of an absorber film having a function of absorbing exposure light is large, and the thickness of a resist film necessary for forming a pattern by etching the absorber film is also large. End up.
- the line width of a pattern required for a mask is narrowed, if a thin line width pattern is formed on a conventional thick resist (usually about 500 nm to 800 nm), first, the aspect ratio may increase and the resist pattern may collapse.
- the etching gas is difficult to be supplied to the narrow passage of the resist pattern, and the gas generated by the etching Therefore, it is difficult for the etching reaction to proceed in the narrow part of the line width, which causes a difference in the etching rate between the wide part and the narrow part, so that uniform etching can be performed within the mask surface. Therefore, if a conventional thick resist is used, a fine pattern with a thin line width such as a resolution of 50 nm or less is used. Formation of it is difficult.
- the object of the present invention is to provide a reflective mask that improves the contrast at the time of inspection with respect to inspection light having a wavelength of 200 nm or less used for pattern inspection, even when a material mainly containing Ru is used for the protective film. It is to provide a blank and a reflective mask manufactured using the same. Secondly, it is to provide a reflective mask blank with improved contrast to exposure light when using the mask and a reflective mask manufactured using the same. A third object is to provide a reflective mask blank using a phase shift effect and a reflective mask manufactured using the same even when a material mainly containing Ru is used for the protective film. Fourthly, it is to provide a reflective mask blank capable of forming a high-resolution fine pattern and a reflective mask manufactured using the same.
- a reflective mask blank having a substrate, a multilayer reflective film that reflects exposure light formed on the substrate, and an absorber film that absorbs exposure light formed on the multilayer reflective film.
- the absorber film has a laminated structure including an uppermost layer and a lower layer other than the uppermost layer, and the uppermost layer is a nitride of at least one element of silicon (Si) and chromium (Cr).
- a reflective mask blank characterized by having a protective film.
- the uppermost layer of the absorber film is made of nitride, oxide, oxynitride, nitrided carbide, or oxynitride carbide of at least one element of silicon (Si) and chromium (Cr).
- the main component is ruthenium (Ru) or a compound thereof with a low reflectivity with respect to the inspection light. Even when a material is used for the protective film, a reflective mask blank with improved contrast during pattern inspection can be provided.
- the uppermost layer of the absorber film is mainly composed of nitride, oxide, oxynitride, nitrided carbide, or oxynitride carbide of at least one element of silicon (Si) and chromium (Cr).
- Si silicon
- Cr chromium
- the adjustment range of the transmittance is relatively narrow.
- the uppermost layer of the absorber film is made of silicon (Si) and chromium (Cr).
- the transmittance of the entire absorber film with respect to EUV exposure light by being formed of a material mainly composed of nitride, oxide, oxynitride, nitride carbide, or oxynitride carbide of at least one element. Adjustment becomes easier, and it becomes easier to adjust the phase difference.
- the lower layer of the absorber film is formed of a chromium (Cr) nitride, oxide, oxynitride, carbide, nitrided carbide, or oxynitride carbide as a main component.
- the lower layer of the absorber film is also made of a chromium-based material (chromium (Cr) nitride, oxide, oxynitride, carbide, nitrided carbide) having lower EUV exposure light absorption than tantalum-based materials.
- a material containing oxynitride carbide as a main component the transmittance of the entire absorber film can be adjusted more easily with respect to EUV exposure light, and the phase difference can be easily adjusted.
- the chromium-based material forming the lower layer of the absorber film is dry-etched with an etching gas of a mixed gas of chlorine and oxygen, but a ruthenium-based material (ruthenium (Ru) or a compound thereof forming a protective film as a main component.
- the material (1) has high resistance to the etching gas, and the protective film can also serve as an etching stopper.
- the uppermost layer of the absorber film is formed of a material mainly composed of silicon (Si) nitride, oxide, oxynitride, carbide, nitrided carbide, or oxynitride carbide, and the protective film
- a reflective mask blank according to Configuration 1 further comprising a buffer film mainly composed of chromium (Cr) between the absorber film and the absorber film.
- the uppermost layer formed of a silicon-based material (a silicon (Si) nitride, oxide, oxynitride, carbide, nitride carbide, or oxynitride carbide as a main component) Since it has high resistance to dry etching of a mixed gas of chlorine and oxygen, the buffer film can be formed of a chromium-based material (material containing chromium as a main component) that is dry-etched with this etching gas.
- a reflective mask wherein an absorber film pattern serving as a transfer pattern for a transfer target is formed on the absorber film of the reflective mask blank according to any one of Structures 1 to 6.
- Manufacturing method By manufacturing a reflective mask using the reflective mask blanks having the above configurations 1 to 6, the contrast at the time of inspection with respect to inspection light having a wavelength of 200 nm or less used for pattern inspection is improved, and the contrast with respect to exposure light when using the mask. And a reflective mask having a phase shift effect can be obtained.
- a reflective mask blank having improved contrast at the time of inspection with respect to inspection light having a wavelength of 200 nm or less used for pattern inspection, and the same are used.
- a reflective mask manufactured in this manner can be provided.
- the reflective mask blank which improved the contrast with respect to the exposure light at the time of mask use and the reflective mask manufactured using it can be provided.
- the reflective mask blank which can form a high-resolution fine pattern, and a reflective mask manufactured using it can be provided.
- the reflective mask blank of the present invention includes a substrate, a multilayer reflective film that reflects exposure light formed on the substrate, and an absorber film that absorbs exposure light formed on the multilayer reflective film.
- It is a type
- membrane has a laminated structure which consists of an uppermost layer and other lower layers, and the said uppermost layer is at least 1 or more of silicon (Si) and chromium (Cr) And a ruthenium (Ru) or a material between the multilayer reflective film and the absorber film.
- the nitride film, the oxide, the oxynitride, the nitrided carbide, or the oxynitride carbide of the element has a protective film containing a compound as a main component. According to such a reflective mask blank, a reflective mask blank and a reflective mask having the following effects can be obtained.
- the protective film is made of ruthenium (Ru) or a material mainly composed of a compound thereof that can reduce the reflectance to inspection light with a wavelength of 200 nm or less used for pattern inspection to the minimum and does not have a very high reflectance for the inspection light.
- ruthenium ruthenium
- the contrast when the short wavelength light having a wavelength of 200 nm or less is used for the pattern inspection is improved.
- an accurate pattern inspection of the mask on which the fine pattern is formed can be performed.
- the exposure light transmittance at the time of using the mask in the uppermost layer can be increased, the mask contrast with respect to the exposure light, for example, EUV light can be improved, and a fine pattern can be transferred with high accuracy.
- Si silicon
- Cr chromium
- the uppermost layer of the absorber film in the present invention is mainly composed of nitride, oxide, oxynitride, nitrided carbide, or oxynitride carbide of at least one element of silicon (Si) and chromium (Cr).
- silicon (Si) nitride, oxide, oxynitride, nitride carbide, or oxynitride carbide include, for example, Si 3 N 4 , SiO 2 , SiON , SiC and the like. These silicon compounds may further contain a transition metal having a relatively small atomic weight such as Mo.
- the N content in the material is in the range of 15 to 60 at%, and the O content is 15 It is preferably in the range of ⁇ 60 at%.
- typical examples of the chromium (Cr) nitride, oxide, oxynitride, nitrided carbide, or oxynitride carbide include CrN, CrNO, CrOCN, and the like.
- the N content in the material is in the range of 15 to 60 at%, and the O content is 15 It is preferably in the range of ⁇ 60 at%.
- the material forming the uppermost layer of the absorber film may further contain boron (B). By containing B, the amorphousness and surface smoothness of the film can be further improved.
- the film thickness of the uppermost layer of the absorber film can be about 5 to 30 nm, but the material forming the uppermost layer in the present invention has the minimum reflectivity for inspection light with a wavelength of 200 nm or less used for pattern inspection. Therefore, it is preferable to optimize the film thickness so that the reflectance is minimized.
- the lower layer of the absorber film is preferably formed of a material mainly composed of nitride (chromium), oxide, oxynitride, carbide, nitride carbide, or oxynitride carbide.
- the lower layer of the absorber film is also mainly composed of a chromium-based material (chromium (Cr) nitride, oxide, oxynitride, carbide, nitrided carbide, or oxynitride carbide) that has a lower absorption rate of EUV exposure light than tantalum-based materials. Therefore, the transmittance of the entire absorber film can be easily adjusted for the EUV exposure light, and the phase difference can be easily adjusted.
- the chromium-based material forming the lower layer of the absorber film is dry-etched by an etching gas of a mixed gas of chlorine and oxygen, but a ruthenium-based material (ruthenium (Ru) or a compound thereof forming a protective film as a main component.
- the material (1) has high resistance to the etching gas, and the protective film can also serve as an etching stopper.
- Specific examples of the chromium-based material can be the same as the specific examples of the chromium-based material used for the uppermost layer.
- the lower layer of the absorber film may be formed of a tantalum material containing tantalum (Ta) as a main component.
- the absorber film when the uppermost layer of the absorber film is formed of a silicon (Si) nitride, oxide, oxynitride, carbide, nitrided carbide, or oxynitride carbide as a main component, the absorber film
- the lower layer is also preferably formed of a tantalum-based material containing tantalum (Ta) as a main component.
- the ruthenium-based material forming the protective film has high resistance to chlorine-based gas, and the protective film can also serve as an etching stopper.
- the lower layer of the absorber film is particularly preferably formed of a tantalum-based material containing tantalum (Ta), boron (B), and nitrogen (N).
- Ta tantalum
- B boron
- N nitrogen
- B the amorphousness and surface smoothness of the absorber film can be further improved.
- N the film
- the uppermost layer and the lower layer of the absorber film do not necessarily have a uniform composition as a whole.
- the composition may be inclined so that the composition differs in the film thickness direction.
- the composition of the contained elements may be continuously different, or the composition may be changed stepwise.
- a buffer film having etching characteristics different from those of the absorber film may be formed between the multilayer reflective film and the absorber film.
- a buffer film made of a chromium-based material containing chromium has high smoothness, the surface of the absorber film formed thereon can also have high smoothness, and pattern blur can be reduced.
- chromium (Cr) alone or at least one element selected from chromium (Cr) and nitrogen (N), oxygen (O), carbon (C), and fluorine (F) is used.
- It can be a material containing.
- the inclusion of nitrogen provides excellent smoothness
- the inclusion of carbon improves the etching resistance of the absorber film under dry etching conditions
- the inclusion of oxygen can reduce film stress.
- materials such as CrN, CrO, CrC, CrF, CrON, CrCO, and CrCON are preferred.
- the reflective mask blank may be in a state in which a resist film for forming a predetermined transfer pattern is formed on the uppermost layer of the absorber film.
- the following aspects are mentioned as a reflective mask obtained using the said reflective mask blank.
- FIG. 1 is a schematic cross-sectional view showing an embodiment of a reflective mask blank of the present invention and a process for producing a reflective mask using the mask blank.
- a multilayer reflective film 2 is formed on a substrate 1
- a protective film 6 is provided thereon, and further thereon.
- the buffer film 3 and the absorber film 4 having a laminated structure of the lower layer 4a and the uppermost layer 4b are formed.
- a resist film 5 is provided on the upper surface of the absorber film 4.
- the substrate 1 has a range of 0 ⁇ 1.0 ⁇ 10 ⁇ 7 / ° C., more preferably within a range of 0 ⁇ 0.3 ⁇ 10 ⁇ 7 / ° C. in order to prevent pattern distortion due to heat during exposure. Those having a low coefficient of thermal expansion are preferred.
- a material having a low thermal expansion coefficient in this range any of amorphous glass, ceramic, and metal can be used.
- amorphous glass SiO 2 —TiO 2 glass, quartz glass, and crystallized glass
- crystallized glass in which ⁇ -quartz solid solution is precipitated can be used.
- metal substrates include Invar alloys (Fe—Ni alloys).
- a single crystal silicon substrate can also be used.
- the substrate 1 is preferably a substrate having high smoothness and flatness in order to obtain high reflectivity and high transfer accuracy.
- the substrate 1 preferably has high rigidity in order to prevent deformation of the film formed thereon due to film stress.
- those having a high Young's modulus of 65 GPa or more are preferable.
- unit Rms which shows smoothness is a root mean square roughness, and can be measured with an atomic force microscope.
- the flatness is a value representing the warpage (deformation amount) of the surface indicated by TIR (Total Indicated Reading), and a plane determined by the least square method with the substrate surface as a reference is a focal plane and is above the focal plane. This is the absolute value of the height difference between the highest position on the substrate surface and the lowest position on the substrate surface below the focal plane.
- the multilayer reflective film 2 is a multilayer film in which elements having different refractive indexes are periodically stacked.
- a thin film of a heavy element or a compound thereof, a thin film of a light element or a compound thereof, A multilayer film in which about 40 to 60 cycles are alternately stacked is used.
- a multilayer reflective film for EUV light having a wavelength of 13 to 14 nm a Mo / Si periodic laminated film in which the aforementioned Mo film and Si film are alternately laminated for about 40 cycles is preferably used.
- Ru / Si periodic multilayer film As the multilayer reflective film used in the EUV light region, Ru / Si periodic multilayer film, Mo / Be periodic multilayer film, Mo compound / Si compound periodic multilayer film, Si / Nb periodic multilayer film, Si / Mo / Examples include Ru periodic multilayer films, Si / Mo / Ru / Mo periodic multilayer films, and Si / Ru / Mo / Ru periodic multilayer films.
- the material may be appropriately selected depending on the exposure wavelength.
- the multilayer reflective film 2 can be formed by depositing each layer by DC magnetron sputtering or ion beam sputtering.
- a Si film having a thickness of about several nm is first formed using a Si target, and then a Mo film having a thickness of about several nm is formed using the Mo target. A film is formed, and this is set as one period. After 40 to 60 periods are laminated, a Si film is finally formed.
- the protective film 6 made of ruthenium (Ru) or a compound thereof is provided between the multilayer reflective film 2 and the buffer film 3.
- ruthenium (Ru) or a compound thereof is provided between the multilayer reflective film 2 and the buffer film 3.
- Examples of typical ruthenium compounds of the protective film in the present invention include RuNb and RuZr.
- the buffer film 3 for example, the chromium-based buffer film described above can be preferably used.
- the buffer film 3 can be formed on the protective film by a sputtering method such as ion beam sputtering other than DC sputtering and RF sputtering.
- the film thickness of the buffer film 3 is preferably about 20 to 60 nm, for example, when correcting the absorber film pattern using a focused ion beam (FIB), but when correcting with an electron beam or the like.
- the thickness may be about 5 to 15 nm.
- the absorber film 4 has a function of absorbing, for example, EUV light that is exposure light.
- the absorber film 4 has a laminated structure of a lower layer 4a and an uppermost layer 4b.
- the uppermost layer 4b is as described above.
- the lower layer 4a is preferably made of a material mainly composed of, for example, tantalum (Ta) in the present invention.
- the material mainly composed of Ta is usually an alloy of Ta.
- Such an absorber film preferably has an amorphous or microcrystalline structure in terms of smoothness and flatness.
- a material having Ta as a main component a material containing Ta and B, a material containing Ta and N, a material containing Ta and B and further containing at least one of O and N, a material containing Ta and Si, Ta A material containing Si and N, a material containing Ta and Ge, a material containing Ta, Ge and N can be used.
- B, Si, Ge or the like an amorphous material can be easily obtained and the smoothness can be improved.
- N or O is added to Ta, resistance to oxidation is improved, so that an effect that stability with time can be improved is obtained.
- a material containing Ta and B (composition ratio Ta / B is in the range of 8.5 / 1.5 to 7.5 / 2.5), Ta, B and N are included. Materials (N is 5 to 30 atomic%, and B is 10 to 30 atomic% when the remaining component is 100). In the case of these materials, a microcrystalline or amorphous structure can be easily obtained, and good smoothness and flatness can be obtained.
- the uppermost layer of the absorber film and the lower layer of the absorber film containing Ta as a main component are preferably formed by a sputtering method such as magnetron sputtering.
- a target containing tantalum and boron can be used and a film can be formed by a sputtering method using an argon gas to which nitrogen is added.
- the internal stress can be controlled by changing the power and gas pressure supplied to the sputtering target.
- it since it can be formed at a low temperature of about room temperature, the influence of heat on the multilayer reflective film and the like can be reduced.
- the film thickness of the uppermost layer 4b of the absorber film 4 is as described above.
- the film thickness of the lower layer 4a may be a thickness that can sufficiently absorb, for example, EUV light as exposure light, but usually 50 to It is about 100 nm.
- the film thickness is preferably as thin as about 25 to 50 nm.
- the reflective mask blank 10 is configured as described above and has a buffer film.
- the buffer film may not be provided.
- each layer of the reflective mask blank 10 (see FIG. 1A) are as described above.
- a predetermined transfer pattern is formed on the uppermost layer 4 b of the absorber film 4 of the reflective mask blank 10.
- a predetermined pattern is drawn on the resist film 5 on the absorber film 4 by using an electron beam drawing machine, and this is developed to form a predetermined resist pattern 51 (see FIG. 5B). ).
- the uppermost layer 4b of the absorber film 4 is dry-etched to form an uppermost layer pattern 41b having a predetermined transfer pattern (see FIG. 10C).
- the uppermost layer 4b is made of a material including, for example, a Si nitride portion, dry etching using a fluorine-based gas such as SF 6 or CHF 3 can be used.
- the lower layer 4a of the absorber film 4 is dry-etched as a formed uppermost layer pattern 41b mask to form a lower layer pattern 41a having a predetermined transfer pattern (Refer to FIG. 4D).
- the lower layer 4a is made of a material mainly composed of Ta, dry etching using chlorine gas can be used.
- the absorber film pattern (laminated pattern of the lower layer pattern 41a and the uppermost layer pattern 41b) is formed as designed. Inspection light used for pattern inspection is incident on the mask on which the absorber film pattern is formed, and is reflected by the inspection light reflected on the uppermost layer pattern 41b and the buffer film 3 exposed by removing the absorber film 4. Inspection is performed by detecting the inspection light and observing the contrast.
- the reflectance of the uppermost layer pattern 41b with respect to inspection light having a wavelength of 200 nm or less can be reduced to a minimum, and sufficient contrast with respect to inspection light can be obtained between the absorber film 4 and the buffer film 3. Therefore, accurate pattern inspection can be performed.
- pinhole defects white defects
- etching deficient defects black defects
- the buffer film 3 serves as a protective film that protects the multilayer reflective film 2 against FIB irradiation.
- the exposed buffer film 3 is removed in accordance with the absorber film pattern, and a pattern 31 is formed on the buffer film to produce the reflective mask 20 (see FIG. 5E).
- a pattern 31 is formed on the buffer film to produce the reflective mask 20 (see FIG. 5E).
- dry etching using a mixed gas containing chlorine and oxygen can be used.
- the multilayer reflective film 2 that is a reflection region of the exposure light is exposed.
- a protective film 6 is formed on the exposed multilayer reflective film. At this time, the protective film 6 protects the multilayer reflective film 2 against dry etching of the buffer film 3.
- an inspection for final confirmation as to whether or not the absorber film pattern is formed with a dimensional accuracy according to the specification is performed. Also in the case of this final confirmation inspection, the above-described inspection light is used.
- a sufficient pattern inspection can be obtained between the absorber film 4 and the multilayer reflective film 2 having the protective film 6 on the surface, so that inspection light with a wavelength of 200 nm or less can be obtained.
- a reflective mask manufactured using the reflective mask blank of the present invention is particularly suitable when EUV light (with a wavelength of about 0.2 to 100 nm) is used as exposure light. Can also be used as appropriate.
- Example 1 The substrate to be used is a SiO 2 —TiO 2 glass substrate (152.4 mm square, thickness 6.35 mm). This substrate has a thermal expansion coefficient of 0.2 ⁇ 10 ⁇ 7 / ° C. and a Young's modulus of 67 GPa. This glass substrate was formed by mechanical polishing to have a smooth surface of 0.2 nmRms or less and a flatness of 50 nm or less. As the multilayer reflective film formed on the substrate, a Mo film / Si film periodic multilayer reflective film was employed in order to obtain a multilayer reflective film suitable for an exposure light wavelength band of 13 to 14 nm.
- the multilayer reflective film was formed by alternately stacking on the substrate by ion beam sputtering using a Mo target and a Si target.
- the Si film is 4.2 nm
- the Mo film is 2.8 nm, and this is one period.
- the Si film is formed to 4.2 nm
- a RuNb film was formed to 2.5 nm.
- a substrate with a multilayer reflective film was thus obtained.
- the reflectance of this multilayer reflective film was measured with 13.5 nm EUV light at an incident angle of 6.0 degrees, the reflectance was 66.1%.
- a buffer film was formed on the protective film of the multilayer reflective film-coated substrate obtained as described above.
- a chromium nitride film was formed to a thickness of 10 nm.
- a film was formed by a DC magnetron sputtering method using a mixed gas of argon (Ar) and nitrogen (N 2 ) as a sputtering gas.
- a material containing Ta, B, and N was formed to a thickness of 80 nm as a lower layer of the absorber film on the buffer film. That is, using a target containing Ta and B, 10% nitrogen (N 2 ) was added to argon (Ar), and a film was formed by DC magnetron sputtering. The composition ratio of the formed TaBN film was Ta at 80 at%, B at 10 at%, and N at 10 at%. Subsequently, a material containing SiON having a thickness of 20 nm was formed as the uppermost layer of the absorber film.
- a film was formed by DC magnetron sputtering under a mixed gas in which nitrogen (N 2 ) and oxygen (O 2 ) were added to argon (Ar).
- the film thickness of the uppermost layer was set so that the reflectance was minimized when an ArF excimer laser (wavelength 193 nm) was used as pattern inspection light.
- the composition ratio of the SiON film was 36 at% for Si, 45 at% for O, and 19 at% for N.
- a reflective mask blank of this example was produced as described above.
- a reflective mask for EUV exposure having a design rule of the DRAM hp32 nm generation pattern was produced as follows. First, a resist film for electron beam drawing was formed on the reflective mask blank, a predetermined pattern was drawn using an electron beam drawing machine, and after drawing, a resist pattern was formed by development. The film thickness of the resist film was 100 nm, which is thinner than the conventional film.
- the uppermost layer of the absorber film was dry-etched using a fluorine-based (SF 6 ) gas to form a transfer pattern on the uppermost layer.
- the lower layer of the absorber film is dry-etched with chlorine gas using the uppermost layer on which this transfer pattern is formed as a mask, and the absorber film is formed by stacking the lower layer and the uppermost layer.
- a pattern was formed.
- pattern inspection of the absorber film was performed using ArF excimer laser (wavelength 193 nm) as inspection light.
- the buffer film remaining on the reflective region (the portion without the absorber film pattern) is removed by dry etching according to the absorber film pattern, and a protective film is formed on the surface.
- the multilayer reflective film provided with was exposed to obtain a reflective mask.
- a final confirmation inspection of the obtained reflective mask was performed using an ArF excimer laser (wavelength 193 nm) as inspection light.
- a pattern transfer apparatus 50 equipped with a reflective mask is roughly composed of a laser plasma X-ray source 31, a reduction optical system 32, and the like.
- the reduction optical system 32 uses an X-ray reflection mirror.
- the pattern reflected by the reflective mask 20 is usually reduced to about 1 ⁇ 4. Since the wavelength band of 13 to 14 nm is used as the exposure wavelength, the optical path was set in advance so as to be in a vacuum. In this state, EUV light obtained from the laser plasma X-ray source 31 is incident on the reflective mask 20, and the light reflected here passes through the reduction optical system 32 on the silicon wafer (semiconductor substrate with resist layer) 33. Transcribed to.
- the light incident on the reflective mask 20 is absorbed by the absorber film and is not reflected in the portion having the absorber film pattern, while the light incident on the portion without the absorber film pattern is reflected by the multilayer reflective film.
- the exposure light passing through the reduction optical system 32 exposes the transfer pattern on the resist layer on the silicon wafer 33.
- a resist pattern was formed on the silicon wafer 33 by developing the exposed resist layer.
- the mask contrast of the reflective mask of this example was as high as 1: 1000 at the peak wavelength and 1: 250 in the entire wavelength band of EUV light. It was confirmed that the accuracy was 4.8 nm or less, which is the required accuracy of the DRAM hp32nm design rule.
- Example 2 A reflective mask blank of Example 1 was prepared in the same manner as in Example 1 except that an absorber film was laminated without forming a buffer film on the upper surface of the protective film.
- a reflective mask was manufactured by the same process as in Example 1 except that the manufactured reflective mask blank was used and a dry etching process for the buffer film was performed.
- a final confirmation inspection was performed on the produced reflective mask in the same manner as in Example 1 using an ArF excimer laser (wavelength: 193 nm). That is, an ArF excimer laser (wavelength 193 nm) was used as inspection light, and a final confirmation inspection of the obtained reflective mask was performed.
- the mask contrast of the reflective mask of this example was 1: 1000 at the peak wavelength, and the EUV light The entire wavelength band was as high as 1: 250, and it was confirmed that the mask accuracy was 4.8 nm or less, which is the required accuracy of the DRAM hp32 nm design rule.
- Example 3 A reflective mask blank of Example 2 was prepared in the same manner as in Example 2 except that CrOCN was applied to the uppermost layer of the absorber film.
- the composition ratio of the CrOCN film was 33 at% for Cr, 39 at% for O, 11 at% for C, and 17 at% for N.
- a reflective mask was produced by the same process as in Example 2 except that the produced reflective mask blank was used and the uppermost layer of the absorber film was dry-etched with a mixed gas of chlorine and oxygen.
- a final confirmation inspection was performed on the produced reflective mask in the same manner as in Example 1 using an ArF excimer laser (wavelength: 193 nm).
- an ArF excimer laser (wavelength 193 nm) was used as inspection light, and a final confirmation inspection of the obtained reflective mask was performed.
- the mask contrast of the reflective mask of this example was 1: 1000 at the peak wavelength, and the EUV light The entire wavelength band was as high as 1: 250, and it was confirmed that the mask accuracy was 4.8 nm or less, which is the required accuracy of the DRAM hp32 nm design rule.
- Example 4 A reflective mask blank of Example 3 was prepared in the same manner as in Example 1 except that CrN was applied to the lower layer of the absorber film.
- Example 1 except that the reflective mask blank thus produced was used and the thickness of the resist film was 150 nm, and that the uppermost layer and the lower layer of the absorber film were dry-etched with a mixed gas of chlorine and oxygen.
- a reflective mask was fabricated by the same process as described above.
- a final confirmation inspection was performed on the produced reflective mask in the same manner as in Example 1 using an ArF excimer laser (wavelength: 193 nm). That is, an ArF excimer laser (wavelength 193 nm) was used as inspection light, and a final confirmation inspection of the obtained reflective mask was performed.
- the mask contrast of the reflective mask of this example was 1: 1000 at the peak wavelength, and the EUV light The entire wavelength band was as high as 1: 250, and it was confirmed that the mask accuracy was 6.8 nm or less, which is the required accuracy of the DRAM hp45 nm design rule.
- Example 5 The reflective mask blank of Example 2 is the same as in Example 1 except that CrN is applied to the lower layer of the absorber film (that is, the uppermost layer of the absorber film is formed of SiON).
- a mask blank was prepared.
- a reflective mask was produced in the same process as in Example 1 except that the produced reflective mask blank was used and the lower layer of the absorber film was dry-etched with a mixed gas of chlorine and oxygen.
- a final confirmation inspection was performed on the produced reflective mask in the same manner as in Example 1 using an ArF excimer laser (wavelength: 193 nm). That is, an ArF excimer laser (wavelength 193 nm) was used as inspection light, and a final confirmation inspection of the obtained reflective mask was performed.
- an ArF excimer laser wavelength 193 nm
- the mask contrast of the reflective mask of this example was 1: 1000 at the peak wavelength, and the EUV light The entire wavelength band was as high as 1: 250, and it was confirmed that the mask accuracy was 4.8 nm or less, which is the required accuracy of the DRAM hp32 nm design rule.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Nanotechnology (AREA)
- Crystallography & Structural Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Inorganic Chemistry (AREA)
- Preparing Plates And Mask In Photomechanical Process (AREA)
- Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
Abstract
Description
(1)基板上に、順次、多層反射膜、バッファ膜、および吸収体膜を成膜した反射型マスクブランクの上面に所定のレジストパターンを形成し、該レジストパターンをエッチングマスクとして、ドライエッチングによって吸収体膜に所定のパターンを形成する。
(2)ここで、検査光を用いて、吸収体膜にパターンが設計通りに形成されているかどうかの検査を行う。このとき、吸収体膜で反射される検査光と、吸収体膜が除去されて露出されたバッファ膜で反射される検査光を検出し、そのコントラストを観察することによって検査を行う。
(3)検査の結果、吸収体膜のパターンに白欠陥や黒欠陥があることが判明した場合は、白欠陥に対してはFIBアシストデポジション法等でピンホール等の修復を行い、黒欠陥部分に対してはFIB照射等による不要部分の除去によって修正を行う。
(4)次に、上記パターンが形成された吸収体膜をエッチングマスクとして、ドライエッチングによってバッファ膜を吸収体膜パターンに従って除去し、バッファ膜にパターンを転写する。
(5)最後に、検査光を用いて、形成されたパターンの最終確認検査を行う。このとき、吸収体膜で反射される検査光と、吸収体膜およびバッファ膜が除去されて露出された多層反射膜で反射される検査光を検出し、そのコントラストを観察することによって検査を行う。
(構成1)基板と、該基板上に形成された露光光を反射する多層反射膜と、該多層反射膜上に形成された露光光を吸収する吸収体膜とを有する反射型マスクブランクであって、前記吸収体膜は、最上層と、それ以外の下層とからなる積層構造となっており、前記最上層は、ケイ素(Si)およびクロム(Cr)のうち少なくとも1以上の元素の窒化物、酸化物、酸化窒化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料で形成され、前記多層反射膜と前記吸収体膜との間に、ルテニウム(Ru)又はその化合物を主成分とする保護膜を有することを特徴とする反射型マスクブランク。
また、前記吸収体膜の最上層が、ケイ素(Si)およびクロム(Cr)のうち少なくとも1以上の元素の窒化物、酸化物、酸化窒化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料で形成されていることにより、最上層におけるマスク使用時の露光光透過率を高めるとともに、露光光に対するマスクコントラストを向上させた反射型マスクブランクを提供できる。
構成2によれば、さらに吸収体膜の下層もタンタル系材料に比べてEUV露光光の吸収率が低いクロム系材料(クロム(Cr)の窒化物、酸化物、酸化窒化物、炭化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料)を用いることから、吸収体膜全体でのEUV露光光に対する透過率の調整がさらに容易になり、位相差の調整もし易くなる。
この構成3によれば、シリコン系材料(ケイ素(Si)の窒化物、酸化物、酸化窒化物、炭化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料)で形成された最上層は、塩素と酸素の混合ガスのドライエッチングに対して高い耐性を有するため、このエッチングガスでドライエッチングするクロム系材料(クロムを主成分とする材料)でバッファ膜を形成することができる。
この構成4によれば、吸収体膜の最上層にフッ素系ガスでドライエッチングされるシリコン系材料を適用し、吸収体膜の下層に塩素ガスでドライエッチングされるタンタル系材料を適用したことにより、最上層をエッチングマスクとして機能させることができる。これにより、高解像度の微細パターンを形成することができる。また、保護膜を形成するルテニウム系材料は、塩素系ガスに対して高い耐性を有しており、保護膜にエッチングストッパーとしての役割も持たすことができる。
構成5によれば、吸収体膜の最上層に用いられるシリコン系材料やクロム系材料は、波長200nm以下の検査光に対する反射率が最小にできるため、パターン検査時のコントラストを向上させて正確なパターン検査を行える。
構成6によれば、この反射型マスクブランクから反射型マスクを作製したときに、保護膜が露出することで、この保護膜の表層にニオブ酸化層が形成され、これによって、マスク洗浄時における耐薬性が向上する。特に、オゾン水洗浄に対する耐性が非常に高く、露光光反射率の低下を防止できる。特に、保護層の上面に接してクロムを主成分とするバッファ膜が形成される構成の場合においては、バッファ膜のドライエッチング時の塩素と酸素との混合ガスに対して高い耐性を有する。
上記構成1乃至6の反射型マスクブランクを用いて反射型マスクを製造することにより、パターン検査に用いる波長200nm以下の検査光に対する検査時のコントラストを向上させ、またマスク使用時の露光光に対するコントラストを向上させ、また位相シフト効果を有する反射型マスクが得られる。
また、本発明によれば、マスク使用時の露光光に対するコントラストを向上させた反射型マスクブランク及びそれを用いて製造される反射型マスクを提供することができる。保護膜にRuを主成分とする材料を用いた場合においても、位相シフト効果を利用した反射型マスクブランク及びそれを用いて製造される反射型マスクを提供することができる。
また、本発明によれば、高解像度の微細パターンを形成できる反射型マスクブランク及びそれを用いて製造される反射型マスクを提供することができる。
本発明の反射型マスクブランクは、基板と、該基板上に形成された露光光を反射する多層反射膜と、該多層反射膜上に形成された露光光を吸収する吸収体膜とを有する反射型マスクブランクであって、前記吸収体膜は、最上層と、それ以外の下層とからなる積層構造となっており、前記最上層は、ケイ素(Si)、クロム(Cr)のうち少なくとも1以上の元素の窒化物、酸化物、酸化窒化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料で形成され、前記多層反射膜と前記吸収体膜との間に、ルテニウム(Ru)又はその化合物を主成分とする保護膜を有することを特徴としている。
このような反射型マスクブランクによれば、以下の効果を有する反射型マスクブランクおよび反射型マスクが得られる。
なお、マスクコントラストとは、例えばEUV光を露光光とする反射型マスクのコントラスト、すなわち、コントラスト=反射率比=1:(保護膜を有する多層反射膜からの反射率/吸収体膜からの反射率)で定義される値を意味するものとする。
また、上記クロム(Cr)の窒化物、酸化物、酸化窒化物、窒化炭化物、または酸化窒化炭化物の代表的な化合物例としては、例えば、CrN、CrNO、CrOCN等が挙げられる。これらの材料を吸収体膜の最上層に用いる場合で波長200nm以下の検査光に対する反射率を最小に低減するには、材料中のN含有量は15~60at%の範囲、O含有量は15~60at%の範囲とすることが好ましい。
上記吸収体膜の最上層を形成する材料は、さらにホウ素(B)を含有していてもよい。Bを含有することにより、膜のアモルファス性、表面平滑性をより向上することができる。
また、上記吸収体膜の下層は、本発明においては、タンタル(Ta)を主成分として含有するタンタル系材料で形成されていてもよい。とくに、吸収体膜の最上層が、ケイ素(Si)の窒化物、酸化物、酸化窒化物、炭化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料で形成される場合、吸収体膜の下層は、タンタル(Ta)を主成分として含有するタンタル系材料で形成されることも好ましい。吸収体膜の最上層にフッ素系ガスでドライエッチングされるシリコン系材料を適用し、吸収体膜の下層に塩素ガスでドライエッチングされるタンタル系材料を適用したことにより、最上層をエッチングマスクとして機能させることができる。これにより、高解像度の微細パターンを形成することができる。また、保護膜を形成するルテニウム系材料は、塩素系ガスに対して高い耐性を有しており、保護膜にエッチングストッパーとしての役割も持たすことができる。
本発明においては、吸収体膜の下層は、タンタル(Ta)とホウ素(B)と窒素(N)を含有するタンタル系材料で形成されていることが特に好ましい。Bを含有することにより、吸収体膜のアモルファス性、表面平滑性をより向上することができる。また、Nを含有することにより、吸収体膜の膜応力を低減し、また下層のバッファ膜あるいは多層反射膜との密着性が良好となる。
上記反射型マスクブランクを使用して得られる反射型マスクとしては、以下のような態様が挙げられる。
(1)基板上に形成された多層反射膜の上面に保護膜が設けられ、その上に、所定の転写パターンを有するバッファ膜と吸収体膜のパターンが形成された反射型マスク。
(2)基板上に形成された多層反射膜の上面に保護膜が設けられ、その上に、所定の転写パターンを有する吸収体膜パターンが形成された反射型マスク。
本発明の反射型マスクブランクの一実施の形態としては、図1(a)に示すように、基板1上に多層反射膜2が形成され、その上に保護膜6を設け、更にその上に、バッファ膜3及び、下層4aと最上層4bの積層構造からなる吸収体膜4の各層が形成された構造をしている。また、吸収体膜4の上面にレジスト膜5を有している。
また、基板1は、高反射率及び高転写精度を得るために、高い平滑性と平坦度を備えた基板が好ましい。特に、0.2nmRms以下の平滑な表面(10μm角エリアでの平滑性)と、50m以下の平坦度(基板主表面の142mm角エリアにおける平坦度)を有することが好ましい。また、基板1は、その上に形成される膜の膜応力による変形を防止するために、高い剛性を有しているものが好ましい。特に、65GPa以上の高いヤング率を有しているものが好ましい。
なお、平滑性を示す単位Rmsは、二乗平均平方根粗さであり、原子間力顕微鏡で測定することができる。また平坦度は、TIR(Total Indicated Reading)で示される表面の反り(変形量)を表す値で、基板表面を基準として最小自乗法で定められる平面を焦平面とし、この焦平面より上にある基板表面の最も高い位置と、焦平面より下にある基板表面の最も低い位置との高低差の絶対値である。
例えば、波長13~14nmのEUV光に対する多層反射膜としては、前述のMo膜とSi膜を交互に40周期程度積層したMo/Si周期積層膜が好ましく用いられる。その他に、EUV光の領域で使用される多層反射膜として、Ru/Si周期多層膜、Mo/Be周期多層膜、Mo化合物/Si化合物周期多層膜、Si/Nb周期多層膜、Si/Mo/Ru周期多層膜、Si/Mo/Ru/Mo周期多層膜、Si/Ru/Mo/Ru周期多層膜などがある。露光波長により、材質を適宜選択すればよい。
多層反射膜2は、DCマグネトロンスパッタ法や、イオンビームスパッタ法などにより、各層を成膜することにより形成できる。上述したMo/Si周期多層膜の場合、例えばイオンビームスパッタ法により、まずSiターゲットを用いて厚さ数nm程度のSi膜を成膜し、その後Moターゲットを用いて厚さ数nm程度のMo膜を成膜し、これを一周期として、40~60周期積層した後、最後にSi膜を成膜する。
なお、バッファ膜3の膜厚は、たとえば集束イオンビーム(FIB)を用いた吸収体膜パターンの修正を行う場合には、20~60nm程度とするのが好ましいが、電子線等で修正する場合には、5~15nm程度とすることができる。
Taを主成分とする材料としては、TaとBを含む材料、TaとNを含む材料、TaとBを含み、更にOとNの少なくとも何れかを含む材料、TaとSiを含む材料、TaとSiとNを含む材料、TaとGeを含む材料、TaとGeとNを含む材料、等を用いることが出来る。TaにBやSi、Ge等を加えることにより、アモルファス状の材料が容易に得られ、平滑性を向上させることができる。また、TaにNやOを加えれば、酸化に対する耐性が向上するため、経時的な安定性を向上させることが出来るという効果が得られる。
前述の吸収体膜の最上層、上述のTaを主成分とする吸収体膜の下層は、マグネトロンスパッタリングなどのスパッタ法で形成するのが好ましい。例えば、TaBN膜の場合、タンタルとホウ素を含むターゲットを用い、窒素を添加したアルゴンガスを用いたスパッタリング法で成膜することができる。スパッタ法で形成した場合には、スパッタターゲットに投入するパワーや投入ガス圧力を変化させることにより内部応力を制御できる。また、室温程度の低温での形成が可能であるので、多層反射膜等への熱の影響を少なくすることが出来る。
反射型マスクブランク10(図1(a)参照)の各層の材料及び形成方法については上述した通りである。
そして、この反射型マスクブランク10の吸収体膜4の最上層4bに所定の転写パターンを形成する。まず、吸収体膜4上のレジスト膜5に対して、電子線描画機を用いて所定のパターン描画を行い、これを現像して、所定のレジストパターン51を形成する(同図(b)参照)。
最上層パターン41b上に残ったレジストパターン51を除去した後、形成された最上層パターン41bマスクとして、吸収体膜4の下層4aをドライエッチングして、所定の転写パターンを有する下層パターン41aを形成する(同図(d)参照)。下層4aがTaを主成分とする材料からなる場合、塩素ガスを用いたドライエッチングを用いることが出来る。
ピンホール欠陥の修正には、例えば、FIBアシストデポジション法により炭素膜等をピンホールに堆積させるなどの方法がある。また、エッチング不足による欠陥の修正には、FIB照射による不要部分の除去を行うなどの方法がある。このとき、バッファ膜3は、FIB照射に対して、多層反射膜2を保護する保護膜となる。
また、本発明の反射型マスクブランクを用いて製造される反射型マスクは、EUV 光(波長0.2~100nm程度)を露光光として用いた場合に特に好適であるが、他の波長の光に対しても適宜用いることができる。
(実施例1)
使用する基板は、SiO2-TiO2系のガラス基板(152.4mm角、厚さが6.35mm)である。この基板の熱膨張係数は0.2×10-7/℃、ヤング率は67GPaである。そして、このガラス基板は機械研磨により、0.2nmRms以下の平滑な表面と、50nm以下の平坦度に形成した。
基板上に形成される多層反射膜は、13~14nmの露光光波長帯域に適した多層反射膜とするために、Mo膜/Si膜周期多層反射膜を採用した。即ち、多層反射膜は、MoターゲットとSiターゲットを使用し、イオンビームスパッタリングにより基板上に交互に積層して形成した。Si膜を4.2nm、Mo膜を2.8nm、これを一周期として、40周期積層した後、Si膜を4.2nm成膜し、最後に保護膜としてRuNbターゲット(at%比 Ru:Nb=20:80)を用いてRuNb膜を2.5nmに成膜した。
このようにして多層反射膜付き基板を得た。この多層反射膜に対し、13.5nmのEUV光を入射角6.0度で反射率を測定したところ、反射率は66.1%であった。
続いて、吸収体膜の最上層として、SiONを含む材料を20nmの厚さで形成した。即ち、Siターゲットを用いて、アルゴン(Ar)に窒素(N2)と酸素(O2)を添加した混合ガス下で、DCマグネトロンスパッタリング法によって成膜した。なお、上記最上層は、ArFエキシマレーザー(波長193nm)をパターンの検査光として用いた場合、反射率が最小となるように膜厚を設定した。SiON膜の組成比は、Siが36at%、Oが45at%、Nが19at%であった。
以上のようにして本実施例の反射型マスクブランクを作製した。
まず、上記反射型マスクブランク上に電子線描画用レジスト膜を形成し、電子線描画機を使用して所定のパターン描画を行い、描画後、現像によりレジストパターンを形成した。なお、上記レジスト膜の膜厚は従来よりも薄い100nmとした。
この段階で、検査光としてArFエキシマレーザー(波長193nm)を使用して吸収体膜のパターン検査を行った。ArFエキシマレーザーの検査光に対するコントラストは、吸収体膜からの反射率:バッファ膜からの反射率=9.5%:53.1%=1:5.59であり、吸収体膜のパターン検査には十分なコントラストが得られることが確認できた。
さらに、塩素と酸素の混合ガスを用いて、反射領域上(吸収体膜のパターンのない部分)に残存しているバッファ膜を吸収体膜のパターンに従ってドライエッチングして除去し、表面に保護膜を備えた多層反射膜を露出させ、反射型マスクを得た。
反射型マスクを搭載したパターン転写装置50は、レーザープラズマX線源31、縮小光学系32等から概略構成される。縮小光学系32は、X線反射ミラーを用いている。縮小光学系32により、反射型マスク20で反射されたパターンは通常1/4程度に縮小される。尚、露光波長として13~14nmの波長帯を使用するので、光路が真空中になるように予め設定した。
このような状態で、レーザープラズマX線源31から得られたEUV光を反射型マスク20に入射し、ここで反射された光を縮小光学系32を通してシリコンウエハ(レジスト層付き半導体基板)33上に転写した。
以上のようにして半導体基板上へのパターン転写を行ったところ、本実施例の反射型マスクのマスクコントラストは、ピーク波長において1:1000、EUV光の波長帯全域でも1:250と高く、マスク精度はDRAM hp32nmデザインルールの要求精度である4.8nm以下であることが確認できた。
実施例1の反射型マスクブランクとは、保護膜の上面にバッファ膜を形成せずに、吸収体膜を積層したこと以外は、実施例1と同様にして反射型マスクブランクを作製した。
また、作製した反射型マスクブランクを用い、バッファ膜に対するドライエッチングを行うプロセス以外は、実施例1と同様のプロセスで反射型マスクを作製した。
作製した反射型マスクに対して、実施例1と同様に、ArFエキシマレーザー(波長193nm)を用いて最終確認検査を行った。即ち、検査光としてArFエキシマレーザー(波長193nm)を使用して、得られた反射型マスクの最終確認検査を行った。ArFエキシマレーザーの検査光に対するコントラストは、吸収体膜からの反射率:保護膜を有する多層反射膜からの反射率=9.5%:58.1%=1:6.12であり、吸収体膜のパターン検査には十分なコントラストが得られることが確認できた。また、反射型マスクのパターン検査の結果、デザインルールがDRAM hp32nm世代のパターンを設計通りに形成できていることが確認できた。また、反射領域におけるEUV露光光の反射率は、多層反射膜付き基板で測定した反射率からほとんど変わらず、65.8%であった。
さらに、この反射型マスクを用い、実施例1と同様に、半導体基板上へのパターン転写を行ったところ、本実施例の反射型マスクのマスクコントラストは、ピーク波長において1:1000、EUV光の波長帯全域でも1:250と高く、マスク精度はDRAM hp32nmデザインルールの要求精度である4.8nm以下であることが確認できた。
実施例2の反射型マスクブランクとは、吸収体膜の最上層にCrOCNを適用したこと以外は、実施例2と同様にして反射型マスクブランクを作製した。CrOCN膜の組成比は、Crが33at%、Oが39at%、Cが11at%、Nが17at%であった。
また、作製した反射型マスクブランクを用い、吸収体膜の最上層を塩素と酸素の混合ガスでドライエッチングを行うプロセス以外は、実施例2と同様のプロセスで反射型マスクを作製した。
作製した反射型マスクに対して、実施例1と同様に、ArFエキシマレーザー(波長193nm)を用いて最終確認検査を行った。即ち、検査光としてArFエキシマレーザー(波長193nm)を使用して、得られた反射型マスクの最終確認検査を行った。ArFエキシマレーザーの検査光に対するコントラストは、吸収体膜からの反射率:保護膜を有する多層反射膜からの反射率=9.4%:58.1%=1:6.18であり、吸収体膜のパターン検査には十分なコントラストが得られることが確認できた。また、反射型マスクのパターン検査の結果、デザインルールがDRAM hp32nm世代のパターンを設計通りに形成できていることが確認できた。また、反射領域におけるEUV露光光の反射率は、多層反射膜付き基板で測定した反射率からほとんど変わらず、65.8%であった。
さらに、この反射型マスクを用い、実施例1と同様に、半導体基板上へのパターン転写を行ったところ、本実施例の反射型マスクのマスクコントラストは、ピーク波長において1:1000、EUV光の波長帯全域でも1:250と高く、マスク精度はDRAM hp32nmデザインルールの要求精度である4.8nm以下であることが確認できた。
実施例3の反射型マスクブランクとは、吸収体膜の下層にCrNを適用したこと以外は、実施例1と同様にして反射型マスクブランクを作製した。
また、作製した反射型マスクブランクを用い、レジスト膜の膜厚を150nmとしたこと、吸収体膜の最上層および下層を塩素と酸素の混合ガスでドライエッチングを行ったこと以外は、実施例1と同様のプロセスで反射型マスクを作製した。
作製した反射型マスクに対して、実施例1と同様に、ArFエキシマレーザー(波長193nm)を用いて最終確認検査を行った。即ち、検査光としてArFエキシマレーザー(波長193nm)を使用して、得られた反射型マスクの最終確認検査を行った。ArFエキシマレーザーの検査光に対するコントラストは、吸収体膜からの反射率:保護膜を有する多層反射膜からの反射率=9.8%:58.2%=1:5.94であり、吸収体膜のパターン検査には十分なコントラストが得られることが確認できた。また、反射型マスクのパターン検査の結果、デザインルールがDRAM hp45nm世代のパターンを設計通りに形成できていることが確認できた。また、反射領域におけるEUV露光光の反射率は、多層反射膜付き基板で測定した反射率からほとんど変わらず、66.0%であった。
さらに、この反射型マスクを用い、実施例1と同様に、半導体基板上へのパターン転写を行ったところ、本実施例の反射型マスクのマスクコントラストは、ピーク波長において1:1000、EUV光の波長帯全域でも1:250と高く、マスク精度はDRAM hp45nmデザインルールの要求精度である6.8nm以下であることが確認できた。
実施例2の反射型マスクブランクとは、吸収体膜の下層にCrNを適用したこと以外(すなわち、吸収体膜の最上層は、SiONで形成。)は、実施例1と同様にして反射型マスクブランクを作製した。
また、作製した反射型マスクブランクを用い、吸収体膜の下層を塩素と酸素の混合ガスでドライエッチングを行ったこと以外は、実施例1と同様のプロセスで反射型マスクを作製した。
作製した反射型マスクに対して、実施例1と同様に、ArFエキシマレーザー(波長193nm)を用いて最終確認検査を行った。即ち、検査光としてArFエキシマレーザー(波長193nm)を使用して、得られた反射型マスクの最終確認検査を行った。ArFエキシマレーザーの検査光に対するコントラストは、吸収体膜からの反射率:保護膜を有する多層反射膜からの反射率=9.2%:58.0%=1:6.30であり、吸収体膜のパターン検査には十分なコントラストが得られることが確認できた。また、反射型マスクのパターン検査の結果、デザインルールがDRAM hp32nm世代のパターンを設計通りに形成できていることが確認できた。また、反射領域におけるEUV露光光の反射率は、多層反射膜付き基板で測定した反射率からほとんど変わらず、66.0%であった。
さらに、この反射型マスクを用い、実施例1と同様に、半導体基板上へのパターン転写を行ったところ、本実施例の反射型マスクのマスクコントラストは、ピーク波長において1:1000、EUV光の波長帯全域でも1:250と高く、マスク精度はDRAM hp32nmデザインルールの要求精度である4.8nm以下であることが確認できた。
2 多層反射膜
3 バッファ膜
4 吸収体膜
4a 下層
4b 最上層
5 レジスト膜
6 保護膜
10 反射型マスクブランク
20 反射型マスク
50 パターン転写装置
Claims (7)
- 基板と、該基板上に形成された露光光を反射する多層反射膜と、該多層反射膜上に形成された露光光を吸収する吸収体膜とを有する反射型マスクブランクであって、
前記吸収体膜は、最上層と、それ以外の下層とからなる積層構造となっており、
前記最上層は、ケイ素(Si)およびクロム(Cr)のうち少なくとも1以上の元素の窒化物、酸化物、酸化窒化物、炭化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料で形成され、
前記多層反射膜と前記吸収体膜との間に、ルテニウム(Ru)又はその化合物を主成分とする保護膜を有することを特徴とする反射型マスクブランク。 - 前記吸収体膜の下層は、クロム(Cr)の窒化物、酸化物、酸化窒化物、炭化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料で形成されていることを特徴とする請求項1に記載の反射型マスクブランク。
- 前記吸収体膜の最上層は、ケイ素(Si)の窒化物、酸化物、酸化窒化物、炭化物、窒化炭化物、または酸化窒化炭化物を主成分とする材料で形成され、
前記保護膜と前記吸収体膜との間にクロム(Cr)を主成分とするバッファ膜を備えることを特徴とする請求項1に記載の反射型マスクブランク。 - 前記吸収体膜の下層は、タンタル(Ta)を主成分とする材料で形成されていることを特徴とする請求項3に記載の反射型マスクブランク。
- 前記吸収体膜の最上層は、パターン検査に用いる波長200nm以下の検査光に対する反射率が最小となるように膜厚が最適化されていることを特徴とする請求項1乃至4のいずれか一項に記載の反射型マスクブランク。
- 前記保護膜は、ルテニウム(Ru)とニオブ(Nb)とを含有するルテニウム化合物を主成分とすることを特徴とする請求項1乃至5のいずれか一項に記載の反射型マスクブランク。
- 請求項1乃至6のいずれか一項に記載の反射型マスクブランクの前記吸収体膜に、被転写体に対する転写パターンとなる吸収体膜パターンを形成することを特徴とする反射型マスクの製造方法。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2010544111A JP5677852B2 (ja) | 2008-12-26 | 2009-12-24 | 反射型マスクブランク及び反射型マスクの製造方法 |
KR1020177003832A KR101802721B1 (ko) | 2008-12-26 | 2009-12-24 | 반사형 마스크 블랭크 및 반사형 마스크의 제조 방법 |
KR1020117004623A KR101707591B1 (ko) | 2008-12-26 | 2009-12-24 | 반사형 마스크 블랭크 및 반사형 마스크의 제조 방법 |
US13/122,099 US8546047B2 (en) | 2008-12-26 | 2009-12-24 | Reflective mask blank and method of manufacturing a reflective mask |
US14/013,870 US9229315B2 (en) | 2008-12-26 | 2013-08-29 | Reflective mask blank and method of manufacturing a reflective mask |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2008-332212 | 2008-12-26 | ||
JP2008332212 | 2008-12-26 |
Related Child Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/122,099 A-371-Of-International US8546047B2 (en) | 2008-12-26 | 2009-12-24 | Reflective mask blank and method of manufacturing a reflective mask |
US14/013,870 Division US9229315B2 (en) | 2008-12-26 | 2013-08-29 | Reflective mask blank and method of manufacturing a reflective mask |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010074125A1 true WO2010074125A1 (ja) | 2010-07-01 |
Family
ID=42287732
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2009/071397 WO2010074125A1 (ja) | 2008-12-26 | 2009-12-24 | 反射型マスクブランク及び反射型マスクの製造方法 |
Country Status (5)
Country | Link |
---|---|
US (2) | US8546047B2 (ja) |
JP (2) | JP5677852B2 (ja) |
KR (2) | KR101802721B1 (ja) |
TW (2) | TWI545389B (ja) |
WO (1) | WO2010074125A1 (ja) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015008265A (ja) * | 2013-05-31 | 2015-01-15 | 旭硝子株式会社 | Euvリソグラフィ用反射型マスクブランク |
JP2016046370A (ja) * | 2014-08-22 | 2016-04-04 | Hoya株式会社 | 反射型マスクブランク及びその製造方法、反射型マスクの製造方法、並びに半導体装置の製造方法 |
JP2017004008A (ja) * | 2016-09-07 | 2017-01-05 | Hoya株式会社 | マスクブランク、位相シフトマスクの製造方法および半導体デバイスの製造方法 |
TWI603144B (zh) * | 2010-12-17 | 2017-10-21 | Hoya股份有限公司 | 光罩基底、轉印用光罩、轉印用光罩之製造方法及半導體裝置之製造方法 |
JP2018109780A (ja) * | 2018-03-02 | 2018-07-12 | Hoya株式会社 | マスクブランク、位相シフトマスクおよびこれらの製造方法 |
WO2018159785A1 (ja) * | 2017-03-02 | 2018-09-07 | Hoya株式会社 | 反射型マスクブランク、反射型マスク及びその製造方法、並びに半導体装置の製造方法 |
US10180622B2 (en) | 2013-01-15 | 2019-01-15 | Hoya Corporation | Mask blank, phase-shift mask, method of manufacturing mask blank, method of manufacturing phase-shift mask and method of manufacturing semiconductor device |
US11150550B2 (en) | 2017-08-10 | 2021-10-19 | AGC Inc. | Reflective mask blank and reflective mask |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013077430A1 (ja) * | 2011-11-25 | 2013-05-30 | 旭硝子株式会社 | Euvリソグラフィ用反射型マスクブランクおよびその製造方法 |
US8841047B2 (en) * | 2012-04-02 | 2014-09-23 | Taiwan Semiconductor Manufacturing Company, Ltd. | Extreme ultraviolet lithography process and mask |
US9341941B2 (en) | 2013-08-01 | 2016-05-17 | Samsung Electronics Co., Ltd. | Reflective photomask blank, reflective photomask, and integrated circuit device manufactured by using reflective photomask |
US9075316B2 (en) | 2013-11-15 | 2015-07-07 | Globalfoundries Inc. | EUV mask for use during EUV photolithography processes |
US9739913B2 (en) * | 2014-07-11 | 2017-08-22 | Applied Materials, Inc. | Extreme ultraviolet capping layer and method of manufacturing and lithography thereof |
US9581890B2 (en) | 2014-07-11 | 2017-02-28 | Applied Materials, Inc. | Extreme ultraviolet reflective element with multilayer stack and method of manufacturing thereof |
JP6968945B2 (ja) * | 2016-03-28 | 2021-11-24 | Hoya株式会社 | 反射型マスクブランク、反射型マスク及び半導体装置の製造方法 |
US11204545B2 (en) | 2020-01-16 | 2021-12-21 | Taiwan Semiconductor Manufacturing Co., Ltd. | EUV photo masks and manufacturing method thereof |
KR102583075B1 (ko) * | 2021-01-27 | 2023-09-27 | 주식회사 에스앤에스텍 | 극자외선 리소그래피용 위상반전 블랭크마스크 및 포토마스크 |
JP2022124344A (ja) | 2021-02-15 | 2022-08-25 | 株式会社トッパンフォトマスク | 反射型フォトマスクブランク及び反射型フォトマスク |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007273656A (ja) * | 2006-03-31 | 2007-10-18 | Hoya Corp | 反射型マスクブランクス及び反射型マスク並びに半導体装置の製造方法 |
JP2007335908A (ja) * | 2007-09-18 | 2007-12-27 | Hoya Corp | 反射型マスクブランクス及び反射型マスク |
JP2008078551A (ja) * | 2006-09-25 | 2008-04-03 | Toppan Printing Co Ltd | 反射型フォトマスクブランク及び反射型フォトマスク並びに半導体装置の製造方法 |
JP2008118143A (ja) * | 2002-04-11 | 2008-05-22 | Hoya Corp | 反射型マスクブランクス及び反射型マスク及びそれらの製造方法並びに半導体の製造方法 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08213303A (ja) | 1995-02-03 | 1996-08-20 | Nikon Corp | 反射型x線マスク及びその製造法 |
EP1498936B1 (en) | 2002-04-11 | 2012-11-14 | Hoya Corporation | Reflection type mask blank and reflection type mask and production methods for them |
JP3806702B2 (ja) | 2002-04-11 | 2006-08-09 | Hoya株式会社 | 反射型マスクブランクス及び反射型マスク及びそれらの製造方法並びに半導体の製造方法 |
JP2004207593A (ja) | 2002-12-26 | 2004-07-22 | Toppan Printing Co Ltd | 極限紫外線露光用マスク及びブランク並びにパターン転写方法 |
US20060222961A1 (en) * | 2005-03-31 | 2006-10-05 | Pei-Yang Yan | Leaky absorber for extreme ultraviolet mask |
FR2894691B1 (fr) * | 2005-12-13 | 2008-01-18 | Commissariat Energie Atomique | Procede de fabrication de masque lithographique en reflexion et masque issu du procede |
JP4926521B2 (ja) | 2006-03-30 | 2012-05-09 | Hoya株式会社 | 反射型マスクブランクス及び反射型マスク並びに半導体装置の製造方法 |
JP4867695B2 (ja) | 2006-04-21 | 2012-02-01 | 旭硝子株式会社 | Euvリソグラフィ用反射型マスクブランク |
TWI444757B (zh) * | 2006-04-21 | 2014-07-11 | Asahi Glass Co Ltd | 用於極紫外光(euv)微影術之反射性空白光罩 |
TWI417647B (zh) * | 2006-06-08 | 2013-12-01 | Asahi Glass Co Ltd | Euv微影術用之反射性空白遮光罩及用於彼之具有功能性薄膜的基板 |
JP4998082B2 (ja) | 2007-05-17 | 2012-08-15 | 凸版印刷株式会社 | 反射型フォトマスクブランク及びその製造方法、反射型フォトマスク、並びに、半導体装置の製造方法 |
-
2009
- 2009-12-24 US US13/122,099 patent/US8546047B2/en active Active
- 2009-12-24 KR KR1020177003832A patent/KR101802721B1/ko active IP Right Grant
- 2009-12-24 KR KR1020117004623A patent/KR101707591B1/ko active IP Right Grant
- 2009-12-24 WO PCT/JP2009/071397 patent/WO2010074125A1/ja active Application Filing
- 2009-12-24 JP JP2010544111A patent/JP5677852B2/ja active Active
- 2009-12-25 TW TW103129413A patent/TWI545389B/zh active
- 2009-12-25 TW TW098145239A patent/TWI453530B/zh active
-
2013
- 2013-08-29 US US14/013,870 patent/US9229315B2/en active Active
-
2015
- 2015-01-05 JP JP2015000138A patent/JP5974321B2/ja active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2008118143A (ja) * | 2002-04-11 | 2008-05-22 | Hoya Corp | 反射型マスクブランクス及び反射型マスク及びそれらの製造方法並びに半導体の製造方法 |
JP2007273656A (ja) * | 2006-03-31 | 2007-10-18 | Hoya Corp | 反射型マスクブランクス及び反射型マスク並びに半導体装置の製造方法 |
JP2008078551A (ja) * | 2006-09-25 | 2008-04-03 | Toppan Printing Co Ltd | 反射型フォトマスクブランク及び反射型フォトマスク並びに半導体装置の製造方法 |
JP2007335908A (ja) * | 2007-09-18 | 2007-12-27 | Hoya Corp | 反射型マスクブランクス及び反射型マスク |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI603144B (zh) * | 2010-12-17 | 2017-10-21 | Hoya股份有限公司 | 光罩基底、轉印用光罩、轉印用光罩之製造方法及半導體裝置之製造方法 |
US10180622B2 (en) | 2013-01-15 | 2019-01-15 | Hoya Corporation | Mask blank, phase-shift mask, method of manufacturing mask blank, method of manufacturing phase-shift mask and method of manufacturing semiconductor device |
US10539866B2 (en) | 2013-01-15 | 2020-01-21 | Hoya Corporation | Mask blank, phase-shift mask, and method of manufacturing semiconductor device |
US10942442B2 (en) | 2013-01-15 | 2021-03-09 | Hoya Corporation | Mask blank, phase-shift mask, and method of manufacturing semiconductor device |
JP2015008265A (ja) * | 2013-05-31 | 2015-01-15 | 旭硝子株式会社 | Euvリソグラフィ用反射型マスクブランク |
JP2016046370A (ja) * | 2014-08-22 | 2016-04-04 | Hoya株式会社 | 反射型マスクブランク及びその製造方法、反射型マスクの製造方法、並びに半導体装置の製造方法 |
JP2017004008A (ja) * | 2016-09-07 | 2017-01-05 | Hoya株式会社 | マスクブランク、位相シフトマスクの製造方法および半導体デバイスの製造方法 |
WO2018159785A1 (ja) * | 2017-03-02 | 2018-09-07 | Hoya株式会社 | 反射型マスクブランク、反射型マスク及びその製造方法、並びに半導体装置の製造方法 |
US11237472B2 (en) | 2017-03-02 | 2022-02-01 | Hoya Corporation | Reflective mask blank, reflective mask and manufacturing method thereof, and semiconductor device manufacturing method |
US11150550B2 (en) | 2017-08-10 | 2021-10-19 | AGC Inc. | Reflective mask blank and reflective mask |
US11703751B2 (en) | 2017-08-10 | 2023-07-18 | AGC Inc. | Reflective mask blank and reflective mask |
JP2018109780A (ja) * | 2018-03-02 | 2018-07-12 | Hoya株式会社 | マスクブランク、位相シフトマスクおよびこれらの製造方法 |
Also Published As
Publication number | Publication date |
---|---|
KR101707591B1 (ko) | 2017-02-16 |
TW201040657A (en) | 2010-11-16 |
TWI545389B (zh) | 2016-08-11 |
US9229315B2 (en) | 2016-01-05 |
TWI453530B (zh) | 2014-09-21 |
TW201447472A (zh) | 2014-12-16 |
JP5677852B2 (ja) | 2015-02-25 |
US20140011122A1 (en) | 2014-01-09 |
KR20170019484A (ko) | 2017-02-21 |
KR101802721B1 (ko) | 2017-11-28 |
JPWO2010074125A1 (ja) | 2012-06-21 |
KR20110103386A (ko) | 2011-09-20 |
JP5974321B2 (ja) | 2016-08-23 |
US8546047B2 (en) | 2013-10-01 |
JP2015084447A (ja) | 2015-04-30 |
US20110217633A1 (en) | 2011-09-08 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5974321B2 (ja) | 反射型マスクブランク及び反射型マスクの製造方法 | |
JP5507876B2 (ja) | 反射型マスクブランク及び反射型マスクの製造方法 | |
JP5638769B2 (ja) | 反射型マスクブランクの製造方法及び反射型マスクの製造方法 | |
JP4926521B2 (ja) | 反射型マスクブランクス及び反射型マスク並びに半導体装置の製造方法 | |
JP4163038B2 (ja) | 反射型マスクブランク及び反射型マスク並びに半導体の製造方法 | |
JP5372455B2 (ja) | 反射型マスクブランク及び反射型マスク、並びにこれらの製造方法 | |
JP4553239B2 (ja) | 反射型マスクブランクス及び反射型マスク並びに半導体装置の製造方法 | |
US20100084375A1 (en) | Method of producing a reflective mask | |
JP4418700B2 (ja) | 反射型マスクブランクス及び反射型マスク並びに半導体装置の製造方法 | |
JP4320050B2 (ja) | 反射型マスクブランクス及びその製造方法、反射型マスク | |
JP2004281967A (ja) | 反射型マスクブランクス及び反射型マスク |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 09834923 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 20117004623 Country of ref document: KR Kind code of ref document: A |
|
ENP | Entry into the national phase |
Ref document number: 2010544111 Country of ref document: JP Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13122099 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 09834923 Country of ref document: EP Kind code of ref document: A1 |