WO2002032622A1 - A method to avoid striae in euv lithography mirrors - Google Patents

A method to avoid striae in euv lithography mirrors Download PDF

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Publication number
WO2002032622A1
WO2002032622A1 PCT/US2001/029100 US0129100W WO0232622A1 WO 2002032622 A1 WO2002032622 A1 WO 2002032622A1 US 0129100 W US0129100 W US 0129100W WO 0232622 A1 WO0232622 A1 WO 0232622A1
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WO
WIPO (PCT)
Prior art keywords
glass material
mirror
top face
produce
striae
Prior art date
Application number
PCT/US2001/029100
Other languages
French (fr)
Inventor
Claude L. Davis, Jr.
Michael E. Best
Mary J. Edwards
Thomas W. Hobbs
Gregory L. Murray
Original Assignee
Corning Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Corning Incorporated filed Critical Corning Incorporated
Priority to JP2002535847A priority Critical patent/JP5142444B2/en
Priority to EP01979254A priority patent/EP1324857A4/en
Publication of WO2002032622A1 publication Critical patent/WO2002032622A1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B13/00—Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor
    • B24B13/06—Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor grinding of lenses, the tool or work being controlled by information-carrying means, e.g. patterns, punched tapes, magnetic tapes
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B19/00—Other methods of shaping glass
    • C03B19/14—Other methods of shaping glass by gas- or vapour- phase reaction processes
    • C03B19/1453—Thermal after-treatment of the shaped article, e.g. dehydrating, consolidating, sintering
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B19/00—Other methods of shaping glass
    • C03B19/14—Other methods of shaping glass by gas- or vapour- phase reaction processes
    • C03B19/1469—Means for changing or stabilising the shape or form of the shaped article or deposit
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B23/00—Re-forming shaped glass
    • C03B23/02—Re-forming glass sheets
    • C03B23/023—Re-forming glass sheets by bending
    • C03B23/025—Re-forming glass sheets by bending by gravity
    • C03B23/0252—Re-forming glass sheets by bending by gravity by gravity only, e.g. sagging

Definitions

  • the present invention relates to extreme ultraviolet (EUV) mirrors for EUV lithography. More particularly, it relates to methods for manufacturing EUV mirrors.
  • EUV extreme ultraviolet
  • EUVL Extreme ultraviolet lithography
  • EUVL uses extreme ultraviolet (EUV, also called soft X-ray) radiation with a wavelength in the range of 10 to 14 nanometers (nm) to perform the imaging.
  • EUV extreme ultraviolet
  • optical lithography has been the lithographic technique of choice in the high-volume manufacture of integrated circuits (IC).
  • IC integrated circuits
  • NGL Next-Generation Lithographies
  • EUVL is similar to the optical lithography.
  • the basic optical design for an EUVL system is similar to that of an optical lithographic system. It comprises a light source 1, a condenser 2, a mask (reticle) 4 on a mask stage 5, an optical system 6, and a wafer 7 on a wafer stage 8.
  • Both EUV and optical lithographies use optical systems (cameras) to project images on the masks onto substrates which comprise silicon wafers coated with photo resists.
  • the apparent similarity stops here. Because EUV is strongly absorbed by virtually all materials, EUV imaging must be performed in vacuum, which is achieved by enclosing the system in a chamber 3.
  • the chamber 3 might be further partitioned into different compartments 10 and 20, which have their own vacuum systems. Because EUV is absorbed by most materials, there are no suitable lenses to focus and project an image on mask 4 onto a substrate (wafer) 7. As a result, it is necessary to operate EUVL in a reflective mode instead of a transmissive mode. In the reflective mode, light is reflected from mirrors (not shown; inside the optical system 6), instead of being transmitted through lenses. Even with reflective optics, there are not many materials capable of reflecting EUV. In order to achieve reasonable reflectivities at near normal incidence (i.e., an incident beam landing on the surface of a mirror at an angle close to normal to the surface), the surface of a mirror is typically coated with multilayer, thin-film coatings. These multilayer, thin- film coatings reflect EUV in a phenomenon known as distributed Bragg reflection.
  • the multilayer coatings for the reflective surfaces in EUVL imaging system consist of a large number of alternating layers of materials having dissimilar EUV optical constants. These multilayers provide a resonant reflectivity when the period of the layers is approximately ⁇ /2, where ⁇ is the wavelength.
  • the most promising EUV multilayers are coatings of alternating layers of molybdenuum (Mo) and silicon (Si). These layers are deposited with magnetron sputtering. Each layer of Mo or Si is coated to a thickness of ⁇ /4 of the EUV light so that it will have a periodicity of ⁇ /2. In this type of reflector, a small portion of the incident light is reflected from each silicon surface.
  • the thickness of the layers causes the reflected light waves to interfere constructively. The more layers there are, the more light will be reflected. However, imperfections in the surface coating will eventually diminish the reflectivity return of more coatings.
  • most mirrors in EUVL systems have around 40 alternating layer pairs of Mo:Si. Furthermore, most of these Mo:Si multilayers are optimized to function best with wavelengths at around 13.4 nm, which is the wavelength of a typical laser plasma light source.
  • a typical EUVL optical system or camera (see 6 in FIG. 1) consists of several mirrors (e.g., a four-mirror ring-field camera shown in FIG. 2).
  • the mirrors that comprise the camera must have a very high degree of perfection in surface figure and surface finish in order to achieve diffraction limited imaging. It is predicted that the surface figure (basic shape) of each mirror must be accurate to 0.25 nm rms (root mean square) deviation, or better. In addition to surface figure, stringent requirement must also be placed on the finish of the surfaces.
  • the challenge for a fabricator of optics for EUVL is to achieve the desired levels of surface figure accuracy and surface finish simultaneously.
  • FIG. 2 illustrates a typical prior art four-mirror optical system for EUVL application.
  • Such an optical system is used to project and reduce an image from a mask onto a wafer.
  • the reduction achieved by the optical system permits the printing of a image smaller than that on the mask onto a wafer.
  • the projection operation is typically carried out in a step-and-scan process.
  • a light beam from a light source (see 1 and 2 in FIG. 1) is used to scan the image on the mask.
  • the light beam L reflected from the mask is further reflected by four mirrors Ml, M2, M3 and M4 in succession to project and reduce the image from the mask onto the wafer.
  • mirrors should be substantially invariant to environmental changes, e.g., temperature changes.
  • these mirrors be made of light weight materials with very low coefficients of thermal expansion (CTE).
  • CTE coefficients of thermal expansion
  • ULE glass has a CTE of about 0+30 ppb/°C over the temperature range of 5 to 35 °C.
  • the CTE in ULE glass is a function of the titanium concentration.
  • ULE glass typically contains about 6 to 8 wt. % of TiO 2 . Compositions containing about 7 wt. % TiO 2 have near zero CTE.
  • ULE glass is also unique in that it hAs no crystalline phase. In other words, ULE glass is completely amorphous.
  • ULE glass is a high temperature glass which makes it unsuitable for manufacturing by conventional means. Instead of being poured, it is fabricated by a flame hydrolysis fused glass process which is similar in scope to chemical vapor deposition.
  • ULE glass is formed in layer deposits. This means ULE glass inherently has striae, though these striae are not apparent and do not affect most applications. Although ULE glass has been polished to 0.5 A rms (root mean square) surface roughness, the striae may present problems for stringent applications like EUV mirrors. For example, it can create a mid frequency surface structure that would cause image degradation in mirrors used in the projection systems for EUV microlithography.
  • FIG. 3A illustrates a piece of ULE " glass 31, in which striae 32 are shown.
  • FIG. 3B shows a cylinder of ULE glass 33 with its top ground to give a convex surface. It is apparent that different layers of striae planes are cut across, leaving approximately concentric circles of striae edges 34. This is not a problem for applications where the source light is in the range of visible to infrared. However, in EUV lithography, which uses lights with wavelengths around 13 nanometer (nm), these striae edges 34 may manifest themselves as small ridges. These can cause aberrations which would degrade any images projected within the optical train.
  • ULE glass Although this problem is illustrated with ULE glass, the problem is not unique to this glass.
  • the same problem due to striae will be encountered in any material that is prepared by gradual deposition of newly formed material onto the materials, like the flame hydrolysis process in the formation of ULE glass.
  • Such materials which inherently have striae, will be generally referred to as the ULE M glass-like materials herein.
  • Embodiments of the invention relate to methods for manufacturing mirrors for use in EUV lithography. Some embodiments include sagging a plate of a glass material to produce a mirror blank; and polishing a top face of the mirror blank to produce a polished mirror. Other embodiments include grinding a top face of a piece of a glass material; sagging a plate of the glass material over the top face of the piece to produce a mirror blank; and polishing a top face of the mirror blank to produce a polished mirror.
  • the glass material may be ultra low expansion glass material with a coefficient of thermal expansion of no more than 30 parts per billion per degree Celsius in a temperature range of 5 to 35 °C.
  • FIG. 1 is a diagram of a prior art EUVL system.
  • FIG. 2 is a diagram illustrating a prior art four-mirror optic system for an
  • FIG. 3 A is a diagram illustrating a piece of a ULE glass-like material having striae.
  • FIG. 3B illustrates a cylindrical piece of a ULE glass-like material. The top of the cylinder has been ground to a convex configuration.
  • FIG. 4A is a diagram illustrating a side view of a thin plate of a ULE glasslike material showing striae on the side.
  • FIG. 4B shows the same side view after the thin plate was sagged to have a curved surface.
  • FIG. 5A is a diagram illustrating a cylinder of a ULETM glass-like material having striae planes perpendicular to the axis of the cylinder.
  • FIG. 5B is a convex mirror blank prepared from the cylinder shown in FIG. 5A, showing the concentric striae ridges on the convex surface.
  • FIG. 6k shows a top plate made of a ULETM glass-like material about to be attached to a mirror base with a convex top face.
  • FIG. 6B shows a mirror blank with the top plate annealed to the base.
  • Embodiments of the invention relate to methods for manufacturing EUV mirrors from the ULE glass-like materials.
  • the invention significantly reduces the striae effects which might degrade image qualities.
  • Some embodiments relate to methods of manufacturing thin-plate mirrors.
  • FIG. 4A illustrates a side view of a thin plate 41, showing striae 42 on the side.
  • the striae planes are parallel with the surfaces of the plate. If the surface of this plate were to be ground to the desired curvature, the grinding would cut across striae planes, and the above-mentioned problem will be unavoidable.
  • the thin plate 41 is "sagged" to the desired curved surface to produce a mirror blank 43, in which the striae planes 44 remain substantially parallel to the sagged, curved surface of the mirror. Because this sagged, curved surface has a near net shape of the final mirror, only minor polishing and grinding are required to produced a finished mirror.
  • Sagging refers to the process of thermal deformation of a plate-like glass material.
  • the polishing or lapping of a finished mirror may be achieved by any method known in the art.
  • coating of molybdenum (Mo) and silicon (Si) can be accomplished with either magnetron sputtering, ion-beam sputtering, or other suitable methods.
  • magnetron sputtering ion-beam sputtering, or other suitable methods.
  • these mirrors should be coated with multiple alternating layers of Mo and Si. Polishing as used herein may include the Mo:Si coating step.
  • FIG. 1 Another embodiments of the invention relate to methods of manufacturing thick mirrors. With thick mirrors, the above-described sagging method is not applicable. When a mirror is sagged over a form, the material flows. This makes it difficult to maintain enough material to have a desired thickness. This difficulty can be overcome by using a combination of sagging and grinding.
  • FIG. 5A illustrates a thick cylindrical plate/block 53 showing that striae planes 54 are perpendicular to the axis of the cylinder.
  • this cylindrical block 53 is first ground to provide a top face with a shape near the net shape of the mirror.
  • a thin plate may be annealed (sagged) to this base.
  • a thin plate 61 with striae planes 62 parallel with the surfaces of the plate may be sagged over the base 63, which is like the one shown in FIG. 5B.
  • the mirror base 63 has a top face with a near net shape and striae ridges 64 due to cut through of striae planes.
  • Mirror 65 has a top face devoid of striae ridges because this top face is the top face of the thin plate 61 as shown in FIG. 6A.
  • annealing the top late 61 to the base 63 include thermal fusion, frit fusion, and annealing using an adhesive (i.e., adhesion).
  • thermal fusion the top plate 61 and the base 63 are fused (joined) by applying thermal energy to melt the regions at the joint.
  • frit fusion low-melting frits (powders) of a glass material are added to the joint to "glue" the pieces together when heated.
  • U.S. Patent No. 6,048,811 which was assigned to the same assignee herein, discloses a frit fusion process suitable for this process.
  • the annealing may be achieve by adhesion, i.e., by applying suitable adhesive materials at the joint.
  • suitable adhesive materials include, but not limited to, epoxies, silicone adhesives, and solder or bonding materials which, upon heating, will melt and form a bond between the base and the faceplate.
  • the faceplate is constructed of a material having a CTE closely equivalent or identical to that of the base, the adhesive should ideally match the CTE.

Abstract

A method for manufacturing an EUV lithography element mirror includes sagging a plate of a glass material (41) to produce an EUV mirror blank (43) and polishing a top face of the EUV mirror blank (43) to produce a polished EUV mirror. A method for manufacturing an EUV lithography element mirror includes grinding a top face of a piece of a glass material (61); sagging a plate of the glass material over the top face of the piece (63) to produce an EUV mirror blank (66); and polishing a top face of the EUV mirror blank to produce an EUV polished mirror (65).

Description

A METHOD TO AVOID STRIAE IN EUV LITHOGRAPHY MIRRORS
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority of provisional U.S. Application Serial No. 60/240,303, filed on October 13, 2000, and entitled "Method to Avoid Striae in EUV Mirrors."
FIELD OF THE INVENTION
[0001] The present invention relates to extreme ultraviolet (EUV) mirrors for EUV lithography. More particularly, it relates to methods for manufacturing EUV mirrors.
BACKGROUND OF THE INVENTION
[0002] Extreme ultraviolet (EUV) lithography (EUVL) is a relatively new form of lithography. EUVL uses extreme ultraviolet (EUV, also called soft X-ray) radiation with a wavelength in the range of 10 to 14 nanometers (nm) to perform the imaging. Up to now, optical lithography has been the lithographic technique of choice in the high-volume manufacture of integrated circuits (IC). The constant improvement in optical lithography has allowed it to remain the semiconductor industry's workhorse through the 100 nm or smaller generation of devices. However, to pack even higher density circuits into IC chips, new technologies (Next-Generation Lithographies, NGL) will be required. EUVL is one NGL technology vying to become the successor to optical lithography.
[0003] In many respects, EUVL is similar to the optical lithography. For example, as illustrated in FIG. 1, the basic optical design for an EUVL system is similar to that of an optical lithographic system. It comprises a light source 1, a condenser 2, a mask (reticle) 4 on a mask stage 5, an optical system 6, and a wafer 7 on a wafer stage 8. Both EUV and optical lithographies use optical systems (cameras) to project images on the masks onto substrates which comprise silicon wafers coated with photo resists. However, the apparent similarity stops here. Because EUV is strongly absorbed by virtually all materials, EUV imaging must be performed in vacuum, which is achieved by enclosing the system in a chamber 3. In addition, the chamber 3 might be further partitioned into different compartments 10 and 20, which have their own vacuum systems. Because EUV is absorbed by most materials, there are no suitable lenses to focus and project an image on mask 4 onto a substrate (wafer) 7. As a result, it is necessary to operate EUVL in a reflective mode instead of a transmissive mode. In the reflective mode, light is reflected from mirrors (not shown; inside the optical system 6), instead of being transmitted through lenses. Even with reflective optics, there are not many materials capable of reflecting EUV. In order to achieve reasonable reflectivities at near normal incidence (i.e., an incident beam landing on the surface of a mirror at an angle close to normal to the surface), the surface of a mirror is typically coated with multilayer, thin-film coatings. These multilayer, thin- film coatings reflect EUV in a phenomenon known as distributed Bragg reflection.
[0004] The multilayer coatings for the reflective surfaces in EUVL imaging system consist of a large number of alternating layers of materials having dissimilar EUV optical constants. These multilayers provide a resonant reflectivity when the period of the layers is approximately λ/2, where λ is the wavelength. The most promising EUV multilayers are coatings of alternating layers of molybdenuum (Mo) and silicon (Si). These layers are deposited with magnetron sputtering. Each layer of Mo or Si is coated to a thickness of λ/4 of the EUV light so that it will have a periodicity of λ/2. In this type of reflector, a small portion of the incident light is reflected from each silicon surface. The thickness of the layers causes the reflected light waves to interfere constructively. The more layers there are, the more light will be reflected. However, imperfections in the surface coating will eventually diminish the reflectivity return of more coatings. Currently, most mirrors in EUVL systems have around 40 alternating layer pairs of Mo:Si. Furthermore, most of these Mo:Si multilayers are optimized to function best with wavelengths at around 13.4 nm, which is the wavelength of a typical laser plasma light source.
[0005] A typical EUVL optical system or camera (see 6 in FIG. 1) consists of several mirrors (e.g., a four-mirror ring-field camera shown in FIG. 2). The mirrors that comprise the camera must have a very high degree of perfection in surface figure and surface finish in order to achieve diffraction limited imaging. It is predicted that the surface figure (basic shape) of each mirror must be accurate to 0.25 nm rms (root mean square) deviation, or better. In addition to surface figure, stringent requirement must also be placed on the finish of the surfaces. The challenge for a fabricator of optics for EUVL is to achieve the desired levels of surface figure accuracy and surface finish simultaneously.
[0006] FIG. 2 illustrates a typical prior art four-mirror optical system for EUVL application. Such an optical system is used to project and reduce an image from a mask onto a wafer. The reduction achieved by the optical system permits the printing of a image smaller than that on the mask onto a wafer. The projection operation is typically carried out in a step-and-scan process. In a step-and-scan operation, a light beam from a light source (see 1 and 2 in FIG. 1) is used to scan the image on the mask. The light beam L reflected from the mask is further reflected by four mirrors Ml, M2, M3 and M4 in succession to project and reduce the image from the mask onto the wafer.
[0007] The high degree of precision in figure and finish required for EUVL imaging requires that the mirrors should be substantially invariant to environmental changes, e.g., temperature changes. In order to afford better thermal management, it is preferred that these mirrors be made of light weight materials with very low coefficients of thermal expansion (CTE). One promising material for such application is a ultra low expansion glass material, such as the ULE glass from Corning, Inc.
[0008] ULE glass has a CTE of about 0+30 ppb/°C over the temperature range of 5 to 35 °C. The CTE in ULE glass is a function of the titanium concentration. ULE glass typically contains about 6 to 8 wt. % of TiO2. Compositions containing about 7 wt. % TiO2 have near zero CTE. In addition to having extremely low thermal expansion, ULE glass is also unique in that it hAs no crystalline phase. In other words, ULE glass is completely amorphous. ULE glass is a high temperature glass which makes it unsuitable for manufacturing by conventional means. Instead of being poured, it is fabricated by a flame hydrolysis fused glass process which is similar in scope to chemical vapor deposition. In the flame hydrolysis process, high purity precursors of titanium oxide and silicon oxide are injected into flames to form deposit onto the surface of the growing glass. The process minimizes impurities such as sodium and other alkali or alkaline earth metals. [0009] Due to its unique process of formation, ULE glass is formed in layer deposits. This means ULE glass inherently has striae, though these striae are not apparent and do not affect most applications. Although ULE glass has been polished to 0.5 A rms (root mean square) surface roughness, the striae may present problems for stringent applications like EUV mirrors. For example, it can create a mid frequency surface structure that would cause image degradation in mirrors used in the projection systems for EUV microlithography.
[0010] FIG. 3A illustrates a piece of ULE " glass 31, in which striae 32 are shown.
When the striae are oriented perpendicular to the axis of a mirror and that mirror is subsequently ground and polished to a concave or convex shape, the striae planes are cut across. FIG. 3B shows a cylinder of ULE glass 33 with its top ground to give a convex surface. It is apparent that different layers of striae planes are cut across, leaving approximately concentric circles of striae edges 34. This is not a problem for applications where the source light is in the range of visible to infrared. However, in EUV lithography, which uses lights with wavelengths around 13 nanometer (nm), these striae edges 34 may manifest themselves as small ridges. These can cause aberrations which would degrade any images projected within the optical train. Although this problem is illustrated with ULE glass, the problem is not unique to this glass. The same problem due to striae will be encountered in any material that is prepared by gradual deposition of newly formed material onto the materials, like the flame hydrolysis process in the formation of ULE glass. Such materials, which inherently have striae, will be generally referred to as the ULE M glass-like materials herein.
[0011] To make good use of the ULE glass-like materials, it is desirable to have methods that can reduce the striae effect in the manufacturing of EUV mirrors of ultra low expansion materials.
SUMMARY OF INVENTION
[0012] Embodiments of the invention relate to methods for manufacturing mirrors for use in EUV lithography. Some embodiments include sagging a plate of a glass material to produce a mirror blank; and polishing a top face of the mirror blank to produce a polished mirror. Other embodiments include grinding a top face of a piece of a glass material; sagging a plate of the glass material over the top face of the piece to produce a mirror blank; and polishing a top face of the mirror blank to produce a polished mirror. The glass material may be ultra low expansion glass material with a coefficient of thermal expansion of no more than 30 parts per billion per degree Celsius in a temperature range of 5 to 35 °C.
[0013] Other aspects and advantages of the invention will be apparent from the accompanying descriptions and drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0014] FIG. 1 is a diagram of a prior art EUVL system.
[0015] FIG. 2 is a diagram illustrating a prior art four-mirror optic system for an
EUVL camera.
[0016] FIG. 3 A is a diagram illustrating a piece of a ULE glass-like material having striae. FIG. 3B illustrates a cylindrical piece of a ULE glass-like material. The top of the cylinder has been ground to a convex configuration.
[0017] FIG. 4A is a diagram illustrating a side view of a thin plate of a ULE glasslike material showing striae on the side. FIG. 4B shows the same side view after the thin plate was sagged to have a curved surface.
[0018] FIG. 5A is a diagram illustrating a cylinder of a ULE™ glass-like material having striae planes perpendicular to the axis of the cylinder. FIG. 5B is a convex mirror blank prepared from the cylinder shown in FIG. 5A, showing the concentric striae ridges on the convex surface.
[0019] FIG. 6k shows a top plate made of a ULE™ glass-like material about to be attached to a mirror base with a convex top face. FIG. 6B shows a mirror blank with the top plate annealed to the base.
DETAILED DESCRIPTION
Embodiments of the invention relate to methods for manufacturing EUV mirrors from the ULE glass-like materials. The invention significantly reduces the striae effects which might degrade image qualities. [0021] Some embodiments relate to methods of manufacturing thin-plate mirrors.
FIG. 4A illustrates a side view of a thin plate 41, showing striae 42 on the side. The striae planes are parallel with the surfaces of the plate. If the surface of this plate were to be ground to the desired curvature, the grinding would cut across striae planes, and the above-mentioned problem will be unavoidable. According to one embodiment of the invention, as illustrated in FIG. 4B, instead, the thin plate 41 is "sagged" to the desired curved surface to produce a mirror blank 43, in which the striae planes 44 remain substantially parallel to the sagged, curved surface of the mirror. Because this sagged, curved surface has a near net shape of the final mirror, only minor polishing and grinding are required to produced a finished mirror. The problem associated with cutting across striae planes will be substantially eliminated. Sagging, as used herein, refers to the process of thermal deformation of a plate-like glass material. One skilled in the art would know that the exact conditions (temperature and duration) needed to achieve the desired degree of sagging will depend on the properties of the materials used. For ULE glass, a temperature of over 1300 °C, preferably 1450 - 1500 °C, is typically required.
[0022] The polishing or lapping of a finished mirror may be achieved by any method known in the art. When the mirror has been polished to the desired figure and finish, coating of molybdenum (Mo) and silicon (Si) can be accomplished with either magnetron sputtering, ion-beam sputtering, or other suitable methods. In a typical EUVL application, these mirrors should be coated with multiple alternating layers of Mo and Si. Polishing as used herein may include the Mo:Si coating step.
[0023] Other embodiments of the invention relate to methods of manufacturing thick mirrors. With thick mirrors, the above-described sagging method is not applicable. When a mirror is sagged over a form, the material flows. This makes it difficult to maintain enough material to have a desired thickness. This difficulty can be overcome by using a combination of sagging and grinding.
[0024] According to one embodiment of the invention, FIG. 5A illustrates a thick cylindrical plate/block 53 showing that striae planes 54 are perpendicular to the axis of the cylinder. In this embodiment, this cylindrical block 53 is first ground to provide a top face with a shape near the net shape of the mirror. This produces a mirror base 55, which has a top face with striae planes cut through showing approximately concentric striae ridges 56. Once the mirror base is ground to a near net shape, a thin plate (see 61 in FIG. 6A) may be annealed (sagged) to this base.
[0025] As illustrated in FIG. 6A, a thin plate 61 with striae planes 62 parallel with the surfaces of the plate may be sagged over the base 63, which is like the one shown in FIG. 5B. The mirror base 63 has a top face with a near net shape and striae ridges 64 due to cut through of striae planes. When the thin plate 61 is sagged over the top face of the mirror base 63, it produces a mirror blank 65, which is ready to be polished. Mirror 65 has a top face devoid of striae ridges because this top face is the top face of the thin plate 61 as shown in FIG. 6A. Sagging of thin plate 61 over the mirror base results in the striae planes 67 to remain parallel with the curved top face 66. Thus, in mirror blank 65, all striae ridges are on the side, instead of the top face. Because this mirror 65 has a near net shape, only minor grinding and polishing are needed to produce the finished mirror. This will eliminate or minimize the cutting through of the striae planes and the problems associated with it.
[0026] Several methods known in the art are suitable for annealing the top late 61 to the base 63. These include thermal fusion, frit fusion, and annealing using an adhesive (i.e., adhesion). With thermal fusion, the top plate 61 and the base 63 are fused (joined) by applying thermal energy to melt the regions at the joint. In frit fusion, low-melting frits (powders) of a glass material are added to the joint to "glue" the pieces together when heated. For example, U.S. Patent No. 6,048,811, which was assigned to the same assignee herein, discloses a frit fusion process suitable for this process. Similarly, the annealing may be achieve by adhesion, i.e., by applying suitable adhesive materials at the joint. Suitable adhesive materials include, but not limited to, epoxies, silicone adhesives, and solder or bonding materials which, upon heating, will melt and form a bond between the base and the faceplate. When the faceplate is constructed of a material having a CTE closely equivalent or identical to that of the base, the adhesive should ideally match the CTE.
[0027] While the invention has been described using a limited number of embodiments, those skilled in the art, having the benefit of this disclosure, will appreciate that other variations are possible without departing from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims.

Claims

What is claimed is:
[cl[ A method for manufacturing an EUV lithography element, comprising:
sagging a plate of a glass material to produce a blank; and
polishing a top face of the blank to produce a finished lithography element.
[c2] The method of claim 1, wherein the glass material is made by flame hydrolysis.
[c3] The method of claim 1, wherein the glass material comprises an ultra low expansion glass material.
[c4] The method of claim 3, wherein the ultra low expansion glass material has a coefficient of thermal expansion of no more than about 30 parts per billion per degree Celsius in a temperature range of 5 to 35 degrees Celsius.
[c5] A method for manufacturing a EUV lithography element, comprising:
grinding a top face of a piece of a glass material;
sagging a plate of the glass material over the top face of the piece to produce a blank; and
polishing a top face of the blank to produce a finished lithography element.
[c6] The method of claim 5, wherein the glass material is made by flame hydrolysis.
[c7] The method of claim 5, wherein the glass material comprises an ultra low expansion glass material.
[c8] The method of claim 5, wherein the ultra low expansion glass material has a coefficient of thermal expansion of no more than about 30 parts per billion per degree Celcius in a temperature range of 5 to 35 degrees Celcius.
[c9] A method for manufacturing a mirror, comprising:
sagging a plate of a glass material to produce a mirror blank; and
polishing a top face of the mirror blank to produce a finished mirror. [clO] The method of claim 9, wherein the glass material is made by flame hydrolysis.
[ell] The method of claim 9, wherein the glass material comprises an ultra low expansion glass material.
[cl2] The method of claim 11, wherein the ultra low expansion glass material has a coefficient of thermal expansion of no more than about 30 parts per billion per degree Celsius in a temperature range of 5 to 35 degrees Celsius.
[cl3] A method for manufacturing a mirror, comprising:
grinding a top face of a piece of a glass material;
sagging a plate of the glass material over the top face of the piece to produce a mirror blank; and
polishing a top face of the mirror blank to produce a finished mirror.
[cl4] The method of claim 13, wherein the glass material is made by flame hydrolysis.
[cl5] The method of claim 13, wherein the glass material comprises an ultra low expansion glass material.
[cl6] The method of claim 13, wherein the ultra low expansion glass material has a coefficient of thermal expansion of no more than about 30 parts per billion per degree Celcius in a temperature range of 5 to 35 degrees Celcius.
PCT/US2001/029100 2000-10-13 2001-09-18 A method to avoid striae in euv lithography mirrors WO2002032622A1 (en)

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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004089838A1 (en) * 2003-04-03 2004-10-21 Asahi Glass Company Limited Silica glass containing tio2 and optical material for euv lithography
EP1471038A2 (en) * 2003-04-26 2004-10-27 Schott Glas Process for producing glass articles of doped silica glass
WO2004092082A1 (en) * 2003-04-11 2004-10-28 Nikon Corporation METHOD FOR PRODUCING SiO2-TiO2 BASED GLASS, SiO2-TiO2 BASED GLASS AND EXPOSURE SYSTEM
DE10318935A1 (en) * 2003-04-26 2004-11-18 Schott Glas Production of glass bodies made from doped quartz glass by flame hydrolysis used in extreme ultraviolet light lithography comprises adding precursors to the fuel to form the doped quartz glass and producing a first blank on a target
US6829908B2 (en) 2002-02-27 2004-12-14 Corning Incorporated Fabrication of inclusion free homogeneous glasses
US6832493B2 (en) 2002-02-27 2004-12-21 Corning Incorporated High purity glass bodies formed by zero shrinkage casting
DE102004015766A1 (en) * 2004-03-23 2005-10-13 Schott Ag SiO2-TiO2 glass with increased radiation resistance
US7155936B2 (en) 2003-08-08 2007-01-02 Corning Incorporated Doped silica glass articles and methods of forming doped silica glass boules and articles
EP1795506A1 (en) 2005-12-08 2007-06-13 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass and making method, euv lithographic member and photomask substrate
EP2003098A1 (en) * 2007-06-06 2008-12-17 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass for nanoimprint molds
EP2146244A1 (en) * 2007-05-09 2010-01-20 Nikon Corporation Photomask substrate, photomask substrate forming member, photomask substrate manufacturing method, photomask, and exposure method using photomask
EP2014624A3 (en) * 2007-06-06 2010-04-21 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass for nanoimprint molds
WO2011006759A1 (en) * 2009-07-15 2011-01-20 Heraeus Quarzglas Gmbh & Co. Kg Meniscus lens of synthetic quartz glass and method for the production thereof
JP2013177299A (en) * 2003-04-03 2013-09-09 Asahi Glass Co Ltd METHOD OF MANUFACTURING SILICA GLASS CONTAINING TiO2
EP2757078A1 (en) 2013-01-22 2014-07-23 Shin-Etsu Chemical Co., Ltd. Euv lithography member, making method, and titania-doped quartz glass
KR20140095422A (en) * 2013-01-24 2014-08-01 신에쯔 세끼에이 가부시키가이샤 Silica-titania glass, process for production thereof and silica-titania glass sorting method

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10127086A1 (en) * 2001-06-02 2002-12-05 Zeiss Carl Reflector for electromagnetic waves in wavelength range below 200 mm
JP4158009B2 (en) * 2001-12-11 2008-10-01 信越化学工業株式会社 Synthetic quartz glass ingot and method for producing synthetic quartz glass
US7053017B2 (en) 2002-03-05 2006-05-30 Corning Incorporated Reduced striae extreme ultraviolet elements
US20040025542A1 (en) * 2002-06-07 2004-02-12 Ball Laura J. Method of making extreme ultraviolet lithography glass substrates
JP2004131373A (en) * 2002-09-09 2004-04-30 Corning Inc Method of manufacturing silica and titania extreme ultraviolet ray optical element
US7691279B2 (en) * 2003-03-27 2010-04-06 Hoya Corporation Method of producing a glass substrate for a mask blank and method of producing a mask blank
JP4792706B2 (en) * 2003-04-03 2011-10-12 旭硝子株式会社 Silica glass containing TiO2 and method for producing the same
DE102006020991B4 (en) * 2006-05-04 2009-09-10 Carl Zeiss Ag Process for producing a shaped body of glass or glass ceramic
US20080266651A1 (en) * 2007-04-24 2008-10-30 Katsuhiko Murakami Optical apparatus, multilayer-film reflective mirror, exposure apparatus, and device
JP5287271B2 (en) * 2009-01-13 2013-09-11 旭硝子株式会社 Method for molding silica glass containing TiO2 and optical member for EUV lithography molded thereby
US8524319B2 (en) 2011-11-18 2013-09-03 Memc Electronic Materials, Inc. Methods for producing crucibles with a reduced amount of bubbles
US8857214B2 (en) * 2011-11-18 2014-10-14 Sunedison Semiconductor Limited Methods for producing crucibles with a reduced amount of bubbles
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DE102016217428A1 (en) 2016-09-13 2017-09-07 Carl Zeiss Smt Gmbh Method for processing a workpiece in the manufacture of an optical element
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3958052A (en) * 1974-06-12 1976-05-18 Corning Glass Works Subsurface-fortified glass laminates
US4130437A (en) * 1978-04-12 1978-12-19 Corning Glass Works Photochromic glasses suitable for simultaneous heat treatment and shaping
US4231827A (en) * 1979-03-29 1980-11-04 Ppg Industries, Inc. Press polishing and laminating plastic transparencies using polycarbonate pressing plates
US4282021A (en) * 1978-10-02 1981-08-04 Corning Glass Works Method of making photochromic glasses suitable for simultaneous heat treatment and shaping
US5750448A (en) * 1995-12-12 1998-05-12 Schott Glaswerke Copper(II) oxide-containing aluminophosphate glasses

Family Cites Families (69)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2272342A (en) 1934-08-27 1942-02-10 Corning Glass Works Method of making a transparent article of silica
US2239551A (en) 1939-04-22 1941-04-22 Corning Glass Works Method of making sealing glasses and seals for quartz lamps
BE438752A (en) * 1939-04-22
US2482698A (en) * 1943-05-06 1949-09-20 American Optical Corp Optical lens means having a nonspherical refracting surface
US3130029A (en) * 1959-06-23 1964-04-21 Bausch & Lomb Method for making fused multifocal lenses
US3155748A (en) * 1960-08-03 1964-11-03 American Optical Corp Method of making optical components
US3560182A (en) * 1968-01-24 1971-02-02 Ppg Industries Inc Bending glass sheets
US3930824A (en) * 1974-07-19 1976-01-06 Metrologic Instruments, Inc. Method of forming laser components
US4002512A (en) 1974-09-16 1977-01-11 Western Electric Company, Inc. Method of forming silicon dioxide
JPS54127284A (en) 1978-03-27 1979-10-03 Cho Lsi Gijutsu Kenkyu Kumiai Method of forming reflective pattern
US4344816A (en) 1980-12-19 1982-08-17 Bell Telephone Laboratories, Incorporated Selectively etched bodies
JPS57106031A (en) 1980-12-23 1982-07-01 Toshiba Corp Transferring device for fine pattern
JPS60173551A (en) 1984-02-20 1985-09-06 Hideki Matsumura Pattern transferring method by reflecting projection of light such as x rays or the like
JPS61291427A (en) * 1985-06-17 1986-12-22 Hoya Corp Molded lens and production thererof
US5016265A (en) 1985-08-15 1991-05-14 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Variable magnification variable dispersion glancing incidence imaging x-ray spectroscopic telescope
US5146482A (en) 1985-08-15 1992-09-08 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Multispectral variable magnification glancing incidence x-ray telescope
US4891830A (en) 1986-03-28 1990-01-02 Shimadzu Corporation X-ray reflective mask and system for image formation with use of the same
DE3752314T2 (en) 1986-07-11 2000-09-14 Canon Kk Reduction type projection exposure system of the reflection type for X-ray radiation
US5165954A (en) 1986-09-02 1992-11-24 Microbeam, Inc. Method for repairing semiconductor masks & reticles
JPS63142301A (en) 1986-12-04 1988-06-14 Nikon Corp Optical thin film influenced only slightly by cummulative effect
JPS63142302A (en) 1986-12-04 1988-06-14 Nikon Corp Optical thin film having high resistance to laser light
DE3856054T2 (en) 1987-02-18 1998-03-19 Canon Kk Reflection mask
US4776696A (en) 1987-03-20 1988-10-11 Michael C. Hettrick Optical system for high resolution spectrometer/monochromator
FR2626082B1 (en) 1988-01-14 1991-10-18 Commissariat Energie Atomique INTEGRATED OPTICAL DEVICE FOR SEPARATING POLARIZED COMPONENTS FROM A GUIDED ELECTROMAGNETIC FIELD AND METHOD FOR PRODUCING THE DEVICE
US5003567A (en) 1989-02-09 1991-03-26 Hawryluk Andrew M Soft x-ray reduction camera for submicron lithography
US4917934A (en) * 1989-04-27 1990-04-17 Corning Incorporated Telescope mirror blank and method of production
US5051326A (en) 1989-05-26 1991-09-24 At&T Bell Laboratories X-Ray lithography mask and devices made therewith
US5146518A (en) 1990-03-30 1992-09-08 The Furukawa Electric Co., Ltd. Optical directional coupler device and a method of driving same
US5152819A (en) 1990-08-16 1992-10-06 Corning Incorporated Method of making fused silica
US5043002A (en) 1990-08-16 1991-08-27 Corning Incorporated Method of making fused silica by decomposing siloxanes
JP3153230B2 (en) 1990-09-10 2001-04-03 株式会社日立製作所 Pattern formation method
US5315629A (en) 1990-10-10 1994-05-24 At&T Bell Laboratories Ringfield lithography
US5203977A (en) 1991-03-11 1993-04-20 Regents Of The University Of California Magnetron sputtered boron films and TI/B multilayer structures
US5154744A (en) 1991-08-26 1992-10-13 Corning Incorporated Method of making titania-doped fused silica
US5173930A (en) 1991-11-22 1992-12-22 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration X-ray monochromator
US5304437A (en) 1992-04-03 1994-04-19 At&T Bell Laboratories Mask for x-ray pattern delineation
US5353322A (en) 1992-05-05 1994-10-04 Tropel Corporation Lens system for X-ray projection lithography camera
US5220590A (en) 1992-05-05 1993-06-15 General Signal Corporation X-ray projection lithography camera
US5395738A (en) 1992-12-29 1995-03-07 Brandes; George R. Electron lithography using a photocathode
US5356662A (en) * 1993-01-05 1994-10-18 At&T Bell Laboratories Method for repairing an optical element which includes a multilayer coating
US5332702A (en) 1993-04-16 1994-07-26 Corning Incorporated Low sodium zircon refractory and fused silica process
JP3513236B2 (en) 1993-11-19 2004-03-31 キヤノン株式会社 X-ray mask structure, method for manufacturing X-ray mask structure, X-ray exposure apparatus and X-ray exposure method using the X-ray mask structure, and semiconductor device manufactured using the X-ray exposure method
JP2569426B2 (en) 1994-03-24 1997-01-08 工業技術院長 Superlattice multilayer film manufacturing method
US5605490A (en) 1994-09-26 1997-02-25 The United States Of America As Represented By The Secretary Of The Army Method of polishing langasite
US5510230A (en) 1994-10-20 1996-04-23 At&T Corp. Device fabrication using DUV/EUV pattern delineation
US5521031A (en) 1994-10-20 1996-05-28 At&T Corp. Pattern delineating apparatus for use in the EUV spectrum
JP3064857B2 (en) * 1995-03-28 2000-07-12 株式会社ニコン Optical member for optical lithography and method for producing synthetic quartz glass
US5868605A (en) 1995-06-02 1999-02-09 Speedfam Corporation In-situ polishing pad flatness control
US5637962A (en) 1995-06-09 1997-06-10 The Regents Of The University Of California Office Of Technology Transfer Plasma wake field XUV radiation source
US6007963A (en) 1995-09-21 1999-12-28 Sandia Corporation Method for extreme ultraviolet lithography
US5815310A (en) 1995-12-12 1998-09-29 Svg Lithography Systems, Inc. High numerical aperture ring field optical reduction system
US5698113A (en) 1996-02-22 1997-12-16 The Regents Of The University Of California Recovery of Mo/Si multilayer coated optical substrates
US5737137A (en) 1996-04-01 1998-04-07 The Regents Of The University Of California Critical illumination condenser for x-ray lithography
DE19616922A1 (en) 1996-04-27 1997-10-30 Zeiss Carl Fa High-resolution, bright lens
US6133577A (en) 1997-02-04 2000-10-17 Advanced Energy Systems, Inc. Method and apparatus for producing extreme ultra-violet light for use in photolithography
US6093484A (en) 1997-04-04 2000-07-25 Hoya Corporation Method for the production of glass product
US5956192A (en) 1997-09-18 1999-09-21 Svg Lithography Systems, Inc. Four mirror EUV projection optics
KR100574123B1 (en) * 1997-09-24 2006-04-25 코닝 인코포레이티드 Fused Silica-Titania glass method
JPH11221742A (en) 1997-09-30 1999-08-17 Hoya Corp Grinding method, grinding device, glass substrate for magnetic recording medium and magnetic recording medium
US6118577A (en) 1998-08-06 2000-09-12 Euv, L.L.C Diffractive element in extreme-UV lithography condenser
US6312373B1 (en) 1998-09-22 2001-11-06 Nikon Corporation Method of manufacturing an optical system
US5970751A (en) 1998-09-22 1999-10-26 Corning Incorporated Fused SiO2 -TiO2 glass method
US6048652A (en) 1998-12-04 2000-04-11 Advanced Micro Devices, Inc. Backside polish EUV mask and method of manufacture
US6013399A (en) 1998-12-04 2000-01-11 Advanced Micro Devices, Inc. Reworkable EUV mask materials
US6178221B1 (en) * 1998-12-04 2001-01-23 Advanced Micro Devices, Inc. Lithography reflective mask
US6319634B1 (en) * 1999-03-12 2001-11-20 Corning Incorporated Projection lithography photomasks and methods of making
US6931097B1 (en) 1999-07-22 2005-08-16 Corning Incorporated Extreme ultraviolet soft x-ray projection lithographic method system and lithographic elements
EP1218796A4 (en) 1999-07-22 2006-08-23 Corning Inc Extreme ultraviolet soft x-ray projection lithographic method and mask devices
US6368942B1 (en) 2000-03-31 2002-04-09 Euv Llc Method for fabricating an ultra-low expansion mask blank having a crystalline silicon layer

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3958052A (en) * 1974-06-12 1976-05-18 Corning Glass Works Subsurface-fortified glass laminates
US4130437A (en) * 1978-04-12 1978-12-19 Corning Glass Works Photochromic glasses suitable for simultaneous heat treatment and shaping
US4282021A (en) * 1978-10-02 1981-08-04 Corning Glass Works Method of making photochromic glasses suitable for simultaneous heat treatment and shaping
US4231827A (en) * 1979-03-29 1980-11-04 Ppg Industries, Inc. Press polishing and laminating plastic transparencies using polycarbonate pressing plates
US5750448A (en) * 1995-12-12 1998-05-12 Schott Glaswerke Copper(II) oxide-containing aluminophosphate glasses

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP1324857A4 *

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6829908B2 (en) 2002-02-27 2004-12-14 Corning Incorporated Fabrication of inclusion free homogeneous glasses
US6832493B2 (en) 2002-02-27 2004-12-21 Corning Incorporated High purity glass bodies formed by zero shrinkage casting
US7462574B2 (en) 2003-04-03 2008-12-09 Asahi Glass Company, Limited Silica glass containing TiO2 and optical material for EUV lithography
JP2013177299A (en) * 2003-04-03 2013-09-09 Asahi Glass Co Ltd METHOD OF MANUFACTURING SILICA GLASS CONTAINING TiO2
WO2004089838A1 (en) * 2003-04-03 2004-10-21 Asahi Glass Company Limited Silica glass containing tio2 and optical material for euv lithography
WO2004092082A1 (en) * 2003-04-11 2004-10-28 Nikon Corporation METHOD FOR PRODUCING SiO2-TiO2 BASED GLASS, SiO2-TiO2 BASED GLASS AND EXPOSURE SYSTEM
DE202004021665U1 (en) 2003-04-26 2009-11-26 Schott Ag Glass body of doped quartz glass
EP1471038A3 (en) * 2003-04-26 2005-11-23 Schott Ag Process for producing glass articles of doped silica glass
DE10318935A1 (en) * 2003-04-26 2004-11-18 Schott Glas Production of glass bodies made from doped quartz glass by flame hydrolysis used in extreme ultraviolet light lithography comprises adding precursors to the fuel to form the doped quartz glass and producing a first blank on a target
EP1471038A2 (en) * 2003-04-26 2004-10-27 Schott Glas Process for producing glass articles of doped silica glass
US7155936B2 (en) 2003-08-08 2007-01-02 Corning Incorporated Doped silica glass articles and methods of forming doped silica glass boules and articles
US7589040B2 (en) 2003-08-08 2009-09-15 Corning Incorporated Doped silica glass articles and methods of forming doped silica glass boules and articles
US7172983B2 (en) 2004-03-23 2007-02-06 Schott Ag SiO2-TIO2 Glass body with improved resistance to radiation
DE102004015766A1 (en) * 2004-03-23 2005-10-13 Schott Ag SiO2-TiO2 glass with increased radiation resistance
DE102004015766B4 (en) * 2004-03-23 2016-05-12 Asahi Glass Co., Ltd. Use of a SiO 2 -tiO 2 glass as a radiation-resistant substrate
EP1795506A1 (en) 2005-12-08 2007-06-13 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass and making method, euv lithographic member and photomask substrate
EP2146244A4 (en) * 2007-05-09 2010-04-28 Nikon Corp Photomask substrate, photomask substrate forming member, photomask substrate manufacturing method, photomask, and exposure method using photomask
US8153336B2 (en) 2007-05-09 2012-04-10 Nikon Corporation Photomask substrate, photomask substrate forming member, photomask substrate fabricating method, photomask, and exposing method that uses the photomask
EP2146244A1 (en) * 2007-05-09 2010-01-20 Nikon Corporation Photomask substrate, photomask substrate forming member, photomask substrate manufacturing method, photomask, and exposure method using photomask
EP2014624A3 (en) * 2007-06-06 2010-04-21 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass for nanoimprint molds
EP2003098A1 (en) * 2007-06-06 2008-12-17 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass for nanoimprint molds
US7923394B2 (en) 2007-06-06 2011-04-12 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass for nanoimprint molds
US7935648B2 (en) 2007-06-06 2011-05-03 Shin-Etsu Chemical Co., Ltd. Titania-doped quartz glass for nanoimprint molds
US8850850B2 (en) 2009-07-15 2014-10-07 Heraeus Quarzglas Gmbh & Co. Kg Meniscus lens of synthetic quartz glass and method for the production thereof
WO2011006759A1 (en) * 2009-07-15 2011-01-20 Heraeus Quarzglas Gmbh & Co. Kg Meniscus lens of synthetic quartz glass and method for the production thereof
KR20140094451A (en) 2013-01-22 2014-07-30 신에쓰 가가꾸 고교 가부시끼가이샤 EUV Lithography Member, Making Method, and Titania-Doped Quartz Glass
EP2757078A1 (en) 2013-01-22 2014-07-23 Shin-Etsu Chemical Co., Ltd. Euv lithography member, making method, and titania-doped quartz glass
US9278881B2 (en) 2013-01-22 2016-03-08 Shin-Etsu Chemical Co., Ltd. EUV lithography member, making method, and titania-doped quartz glass
KR20140095422A (en) * 2013-01-24 2014-08-01 신에쯔 세끼에이 가부시키가이샤 Silica-titania glass, process for production thereof and silica-titania glass sorting method
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JP5142444B2 (en) 2013-02-13
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EP1324857A1 (en) 2003-07-09
US20020043080A1 (en) 2002-04-18

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