CN101687696A - Method for removing foreign matter from glass substrate surface and method for processing glass substrate surface - Google Patents
Method for removing foreign matter from glass substrate surface and method for processing glass substrate surface Download PDFInfo
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- CN101687696A CN101687696A CN200880022677A CN200880022677A CN101687696A CN 101687696 A CN101687696 A CN 101687696A CN 200880022677 A CN200880022677 A CN 200880022677A CN 200880022677 A CN200880022677 A CN 200880022677A CN 101687696 A CN101687696 A CN 101687696A
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- 239000011521 glass Substances 0.000 title claims abstract description 149
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- 238000012545 processing Methods 0.000 title claims description 24
- 238000010884 ion-beam technique Methods 0.000 claims abstract description 65
- 238000005530 etching Methods 0.000 claims abstract description 42
- 239000012535 impurity Substances 0.000 claims description 110
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- 230000001133 acceleration Effects 0.000 claims description 24
- 238000001020 plasma etching Methods 0.000 claims description 22
- 239000002002 slurry Substances 0.000 claims description 17
- 238000005299 abrasion Methods 0.000 claims description 16
- 230000007547 defect Effects 0.000 claims description 2
- 239000007789 gas Substances 0.000 description 123
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- 230000000694 effects Effects 0.000 description 13
- 239000000084 colloidal system Substances 0.000 description 12
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- 238000006243 chemical reaction Methods 0.000 description 3
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- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
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Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C15/00—Surface treatment of glass, not in the form of fibres or filaments, by etching
- C03C15/02—Surface treatment of glass, not in the form of fibres or filaments, by etching for making a smooth surface
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C15/00—Surface treatment of glass, not in the form of fibres or filaments, by etching
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C23/00—Other surface treatment of glass not in the form of fibres or filaments
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C23/00—Other surface treatment of glass not in the form of fibres or filaments
- C03C23/0005—Other surface treatment of glass not in the form of fibres or filaments by irradiation
- C03C23/0025—Other surface treatment of glass not in the form of fibres or filaments by irradiation by a laser beam
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C23/00—Other surface treatment of glass not in the form of fibres or filaments
- C03C23/0005—Other surface treatment of glass not in the form of fibres or filaments by irradiation
- C03C23/006—Other surface treatment of glass not in the form of fibres or filaments by irradiation by plasma or corona discharge
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C23/00—Other surface treatment of glass not in the form of fibres or filaments
- C03C23/0075—Cleaning of glass
-
- 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
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- 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
- G03F1/82—Auxiliary processes, e.g. cleaning or inspecting
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
- H01J2237/06—Sources
- H01J2237/08—Ion sources
- H01J2237/0812—Ionized cluster beam [ICB] sources
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
- H01J2237/30—Electron or ion beam tubes for processing objects
- H01J2237/31—Processing objects on a macro-scale
- H01J2237/3151—Etching
Abstract
An object of the invention is to provide a method for removing foreign matter from a glass substrate surface to be finish-processed by a method accompanied with beam irradiation or laser light irradiation on the glass substrate surface. The present invention relates to a method for removing foreign matter from a glass substrate surface, which includes subjecting the glass substrate surface to gascluster ion beam etching at an accelerating voltage of from 5 to 15 keV.
Description
Technical field
The present invention relates to a kind of method of removing impurity from glass substrate surface, especially, relate to the method that the glass substrate surface that has a high flat degree from needs is removed impurity as the glass substrate of the reflective mask that is used for EUV (extreme ultraviolet) photoetching semiconductor fabrication process.More specifically, the present invention relates to a kind of by with the method for on glass substrate surface, restrainting (beam) irradiation or laser irradiation such as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation, the method for removing impurity from pending glass substrate surface.
In addition, the present invention relates to a kind of method, described method comprises from glass substrate surface removes impurity, then by with the method for restrainting irradiation or laser irradiation on glass substrate surface such as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation glass substrate surface being handled.
Background technology
In photoetching technique, known so far being extensive use of by the fine circuitry pattern transfer being made the exposure tool of unicircuit to the wafer.Along with trending towards unicircuit more high integration, more speed and higher functionization, it is meticulousr that unicircuit becomes.Based on this reason, require exposure tool to realize that with high resolving power and long depth of focus the image of circuit pattern forms on wafer surface, and advance the wavelength decreases of exposure light source.Exposure light source is from the g-light of routine (wavelength: 436nm), i-light (wavelength 365nm) and KrF excimer laser (wavelength: 248nm) further progressive, and bring into use ArF excimer laser (wavelength: 193nm).In addition, in order to deal with the unicircuit of future generation that the circuitry lines width will be no more than 100nm, think and use F
2Laser apparatus (wavelength: be likely 157nm) as exposure light source.Yet, also only can cover line width this generation like this up to 70nm even think.
Under this technological trend, it is last and caused people's attention as the many generations after the 45nm to use EUV light to be considered to can be used for live width as the photoetching technique of exposure light source of future generation.Described EUV refers to that only wave band is the light in soft X-ray zone or vacuum ultraviolet (VUV) zone, is meant that particularly wavelength is the light of about 0.2～100nm.At present, research uses 13.5nm as the photoetching light source.About using projection optical system transfer mask pattern, the exposure principle of this EUV photoetching (hereinafter being abbreviated as " EUVL ") is identical with conventional photoetching.Yet, in the energy area of EUV light, owing to there is not material can see through light, therefore can not use dioptric system, but use reflective optics (referring to patent documentation 1) inevitably.
The mask that is used for EUVL is made of following basically: the absorption layer that (1) glass substrate, (2) form on described reflection multilayer film in the reflection multilayer film that forms on the described glass substrate and (3).As reflection multilayer film, use the reflection multilayer film with following structure: the multiple material that the wavelength of exposure light is had different refractivity is at nanoscale cocycle lamination, and Mo and Si are known as representative materials.In addition, Ta and Cr have been studied as the material that is used for absorption layer.As glass substrate,, and studied and used the crystal glass that has the glass of low thermal coefficient of expansion or have low thermal coefficient of expansion even, need have the material of low thermal coefficient of expansion in order when carrying out irradiation, also not produce strain with EUV light.In this manual, the crystal glass that has the glass of low thermal coefficient of expansion and have a low thermal coefficient of expansion is referred to as " low expansion glass " or " super-low expansion glass ".
As low expansion glass or the super-low expansion glass treated as the EUVL mask, use mainly by SiO the most widely
2The silica glass that constitutes has wherein added TiO for the thermal expansivity that reduces glass in described silica glass
2, SnO
2Or ZrO
2As doping agent.
By washing, make glass substrate with the raw material of this glass of high Precision Processing or crystal glass and to it.Handling under the situation of glass substrate, usually, glass substrate surface is ground in advance with high relatively treatment rate, reach until it and have predetermined Flatness and surfaceness; Remove the grinding waste material of impurity by washing as producing because of pre-grinding; Then, by the method with higher processing accuracy glass substrate surface being carried out precision work handles to have required Flatness and surfaceness.As being used for the method that precision work is handled with high processing accuracy, preferably use with the method for on glass substrate surface, restrainting irradiation or laser irradiation, as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation.
Yet, the situation that the impurity that existence is not removed fully by washing remains; And impurity is attached to situation on the glass substrate surface again after washing.When by with the method for on glass substrate surface, restrainting irradiation or laser irradiation such as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation, when the glass substrate surface that has this impurity is carried out the precision work processing, the part that has on the glass substrate surface that has impurity is not processed, and the washing of carrying out in order to remove impurity from glass substrate surface subsequently causes the problem of the convex defective generation of glass.
Patent documentation 1:JP-T-2003-505891
Summary of the invention
In order to solve the foregoing problems of association area, the purpose of this invention is to provide a kind of by with the method for on glass substrate surface, restrainting irradiation or laser irradiation such as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation, from the method for the treatment of that glass substrate surface that precision work is handled is removed impurity.
Another object of the present invention provides a kind of method, wherein after glass substrate surface is removed impurity, by with the method for on glass substrate surface, restrainting irradiation or laser irradiation such as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation, glass substrate surface is handled.
In order to realize aforementioned purpose, the invention provides a kind of method that is used for removing impurity from glass substrate surface, described method is included under the acceleration voltage of 5～15keV carries out the corrosion of gas ion beam to described glass substrate surface.
In addition, the present invention provides a kind of method of removing impurity from glass substrate surface, and described method comprises with being selected from O
2, Ar, B, CO
2, N
2, N
2At least a gas in O and the hydroborons carries out the corrosion of gas ion beam as source gas to described glass substrate surface.
In the present invention, be called " impurity of the present invention is removed method " hereinafter at the whole bag of tricks described in aforementioned two paragraphs.
Removing in the method at impurity of the present invention, is to be no more than to implement the corrosion of gas ion beam under the condition of 20nm at etching extent preferably.
Remove in the method at impurity of the present invention, the preferred glass substrate is that 0 ± 30ppb/ ℃ low expansion glass is made by the thermal expansivity of 20 ℃ or 50～80 ℃.
Remove in the method at impurity of the present invention, preferably before implementing described gas ion beam corrosion, the surfaceness of described glass substrate surface (Rms) is for being not more than 5nm
Remove in the method at impurity of the present invention, preferably under gas bunch size is condition more than 2000, implement described gas ion beam corrosion.
Remove in the method at impurity of the present invention, preferably make remain 3～60 degree by the normal of described glass substrate and the formed angle of gas ion beam of inciding described glass substrate surface in, implement described gas ion beam corrosion.
Preferably when making described glass substrate surface remain on respect to horizontal direction under downward 3～60 states of spending, implement described gas ion beam corrosion herein.
In addition, the present invention provides a kind of method of handling glass substrate surface, and described method comprises the steps:
By the impurity of the present invention method of removing the impurity on the described glass substrate surface is removed; And
Handle described glass substrate surface by the treatment process (this method will be called " treatment process of the present invention (1) " hereinafter) that is selected from ion beam etching, gas ion beam burn into plasma etching and the nanometer abrasion.
In treatment process of the present invention (1), preferred described treatment process is the corrosion of gas ion beam.
Herein, preferably surpassing under the acceleration voltage of 15keV, the gas ion beam of using mixed gas to implement in the described treatment step as source gas is corroded, and described mixed gas is selected from: SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3And O
2Mixed gas; NF
3, Ar and O
2Mixed gas; NF
3And N
2Mixed gas; And NF
3, Ar and N
2Mixed gas.
Preferred described source gas is to be selected from any one following mixed gas: SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3And O
2Mixed gas; And NF
3, Ar and O
2Mixed gas.
In addition, the present invention provides a kind of method of handling glass substrate surface, and described method comprises the steps:
Measure the Flatness of described glass substrate surface;
By the impurity of the present invention method of removing the impurity on the described glass substrate surface is removed; And
Handle described glass substrate surface by the treatment process that is selected from ion beam etching, gas ion beam burn into plasma etching and the nanometer abrasion,
Wherein in the step of handling described glass substrate surface, the result who obtains according to step from described mensuration Flatness, treatment condition (hereinafter, this method being called " treatment process of the present invention (2) ") to each set positions glass substrate surface of described glass substrate.
In treatment process of the present invention (2), preferred described treatment process is ion beam etching, the corrosion of gas ion beam or plasma etching; According to the result that the step from described mensuration glass substrate surface Flatness obtains, stipulate ripple (waviness) width that exists on the described glass substrate surface; And with the bundle described glass substrate surface is handled, the beam diameter with FWHM (halfwidth) value representation of described bundle is not more than described waviness width.
Herein, the FWHM value of preferred described beam diameter is for being not more than 1/2 of described waviness width.
In treatment process of the present invention (2), preferred described treatment process is the corrosion of gas ion beam; And surpassing under the acceleration voltage of 15keV, the described gas ion beam of using mixed gas to implement in the described treatment step as source gas is corroded, and described mixed gas is selected from: SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3And O
2Mixed gas; NF
3, Ar and O
2Mixed gas; NF
3And N
2Mixed gas; And NF
3, Ar and N
2Mixed gas.
More preferably described source gas is to be selected from any one following mixed gas: SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3And O
2Mixed gas; And NF
3, Ar and O
2Mixed gas.
In treatment process of the present invention (1) and (2), preferably after the step of described processing glass substrate surface, implement to be used to improve second treatment step of the surfaceness of described glass substrate surface.
As second treatment step, preferably, use independent O more than the 3keV and under the acceleration voltage less than 30keV
2Gas or O
2Be selected from Ar, CO and CO
2In the gas ion beam corrosion implemented as source gas of the mixed gas of at least a gas.
As second treatment step, preferably at 1～60gf/cm
2Surface pressure under, the mechanical mill of implement to use grinding slurry.
In addition, the present invention provides the glass substrate that obtains by treatment process of the present invention, and wherein said substrate surface has the Flatness that is no more than 50nm, and does not have highly to surpass the convex glass defect of 1.5nm.
According to the present invention, by with at the method for restrainting irradiation or laser irradiation on the glass substrate surface such as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation glass substrate surface being carried out under the situation that precision work handles, can stop the convex defective that produces glass on the glass substrate surface after handling, and described glass substrate surface is processed into the Flatness with excellence and the surface of surfaceness.
Description of drawings
Fig. 1 removes the synoptic diagram that concerns between the treat surface of substrate in the method and the GCIB for showing impurity of the present invention.
Employed Reference numeral is expressed as follows meaning respectively in the accompanying drawing.
1: substrate
10: treat surface
Embodiment
The impurity method of removing of the present invention relates to, by with the method for on the glass substrate bottom surface, restrainting irradiation or laser irradiation such as ion beam etching, gas ion beam burn into plasma etching with by means of the nanometer abrasion of laser irradiation, from treating that the glass substrate surface (also this glass substrate surface being called " treat surface ") that precision work is handled is the method that treat surface is removed impurity.
Before handling under the enforcement finishing, this treat surface is washed.In the case, the situation that exists the impurity do not removed fully by washing to remain; Or impurity is attached to the situation on the glass substrate surface after the washing again.The purpose that impurity of the present invention is removed method is to remove this impurity.
The impurity of removing the target of method as impurity of the present invention is meant by Van der Waals (Vander Waals) power and is attached to the material on the treat surface, rather than be fixed to material on the treat surface by chemical bond, and the size of described impurity is generally 1～2 μ m.
The glass substrate of removing the target of method as impurity of the present invention is to be used for mainly dealing with the more high integration of unicircuit and the glass substrate of the reflective mask of the EUVL of high definition more.The glass substrate that is used for the application is to have little thermal expansivity and the little glass substrate of its scattering.Described glass substrate is that 0 ± 30ppb/ ℃ low expansion glass is made by the thermal expansivity of 20 ℃ or 50～80 ℃ preferably, is that 0 ± 10ppb/ ℃ super-low expansion glass is made by the thermal expansivity of 20 ℃ or 50～80 ℃ more preferably.
Shape, size and the thickness etc. to glass substrate do not carry out particular restriction.Under the situation of the substrate of the reflective mask that is used for EUVL, consider rectangular planar shape, it is shaped as the rectangular plate body.
In the glass substrate of the target of removing method as impurity of the present invention, preferably treat surface is carried out pre-treatment so that have predetermined Flatness and surfaceness.
Although being used for the pretreated ion beam etching, gas ion beam burn into plasma etching of treat surface and nanometer abrasion can be processed into glass substrate surface and have the excellent Flatness and the surface of surfaceness, but consider treatment rate, the particularly treatment rate under the situation of handling the large-area glass substrate surface, these treatment processs are inferior to conventional mechanical mill.On the other hand, the impurity method of describing in detail below of removing of the present invention is that a kind of impurity that will be present on the treat surface is removed and do not handled the method for described treat surface basically.Based on described reason, preferably before enforcement impurity of the present invention is removed method, described treat surface is carried out pre-treatment so that have predetermined Flatness and surfaceness by treatment process with high relatively treatment rate.
Do not carry out particular restriction to being used for pretreated treatment process, but can extensively select in the known treatment method that is used for handling glass surface.Yet, have the grinding pad of big treatment rate and high surface area by use, can once implement milled processed with big area, therefore use mechanical grinding method usually.Except only carrying out the milled processed by means of the grinding function of abrasive grain, the mechanical grinding method of mentioning herein also comprises the method for grinding slurry of using, and described method combination utilizes the grinding function of abrasive grain and the chemical grinding function of chemical.Described mechanical grinding method any one and in grinding for polishing, and employed abrasive tool and abrasive material can suitably be chosen from known abrasive tool and abrasive material.When using mechanical grinding method, in order to make treatment rate big, under the situation of polishing, preferably at 30～70gf/cm
2Surface pressure under, more preferably at 40～60gf/cm
2Surface pressure under, implement described polishing; And under the situation of grinding, preferably at 60～140gf/cm
2Surface pressure under, more preferably at 80～120gf/cm
2Surface pressure under, implement to grind.The described polishing of preferred enforcement makes that polished amount is 100～300 μ m, and preferably implements described grinding, makes that amount of grinding is 1～60 μ m.
Implementing under the pretreated situation, after pre-treatment, the surfaceness of preferred described treat surface (Rms) is for being no more than 5nm, more preferably no more than 1nm.The surfaceness of mentioning in this specification sheets is meant the surfaceness that the zone square with respect to 1～10 μ m measured by atomic force microscope.When the surfaceness of the glass substrate after described pre-treatment surpasses 5nm, needing cost considerable time that treat surface is carried out precision work handles, so that after enforcement impurity of the present invention is removed method, have predetermined Flatness and surfaceness, therefore, this becomes the factor that increases cost.
The impurity method of removing of the present invention is characterised in that, by under the specified conditions that low etching extent is provided with respect to treat surface (hereinafter this condition being called " low etching condition "), implement gas ion beam (hereinafter becoming " GCIB ") corrosion, when making the treatment capacity of described treat surface extremely low, remove impurity from described treat surface.
The GCIB that mentions herein is following method: will be under normal temperature and normal atmosphere spurt in the vacuum apparatus to form gas bunch with pressurized state by means of the expanded polystyrene veneer nozzle for gasiform reactive materials (source gas), described gas bunch carries out ionization then under electron irradiation, and with the GCIB irradiation that obtains on the target to realize corrosion.Described gas bunch a thick atom group or the molecular grouping be made up of several thousand atoms or molecule usually constitute.Remove in the method at impurity of the present invention, by treat surface being implemented the GCIB corrosion, when gas bunch bumps with treat surface,, remove impurity from treat surface thus because of producing multiple collision effect with the solid interaction.Then, owing under low etching condition, described treat surface is implemented the GCIB corrosion, therefore described treat surface is not handled basically.
Remove in the method at impurity of the present invention,, can on this position, optionally implement the GCIB corrosion by there being the position of impurity on the clear and definite treat surface.Yet, be difficult to clear and definite size for the position of the meticulous impurity of about 1～2 μ m and be difficult to optionally implement the GCIB corrosion in this position.Therefore, usually, under low etching condition, the GCIB corrosion is implemented on the entire treatment surface.Under described situation, must on described treat surface, scan GCIB.As the method for scanning GCIB, gloss scanning (luster scanning) and spiral scan are known, can use in these methods any one.
Remove in first embodiment of method at impurity of the present invention, in order under low etching condition treat surface to be implemented the GCIB corrosion, the acceleration voltage that will be used to be applied to accelerating electrode is controlled to be 5～15keV.Under described situation,, precision work implements that employed source gas can be source gas commonly used in the GCIB corrosion for handling glass substrate surface.The specific examples of this conventional source gas comprises SF
6, NF
3, CHF
3, CF
4, C
2F
6, C
3F
8, C
4F
6, SiF
4And COF
2Can use separately or use these gas with the form of mixture.
Be controlled to be 5～15keV by the acceleration voltage that will be applied to accelerating electrode, even source gas commonly used is being used for for treat surface being carried out precision work handle under the enforcement GCIB corrosive situation, etching extent on treat surface is also enough low, and also can remove and be present in the impurity on the treat surface and can not handle described treat surface basically.Under the situation of acceleration voltage less than 5keV, when gas bunch and treat surface bumped, kinetic energy was little, made the impurity that is present on the treat surface not to be removed, and this depends on the size of impurity.Particularly, size can not be removed for the impurity of about 1～2 μ m.Under acceleration voltage surpassed the situation of 15keV, when gas bunch bumped with described treat surface, kinetic energy was big.Therefore, more obvious to the become effect of removing than the meticulous impurity that will be present on the treat surface of the corrosive nature of treat surface; Equally, the treat surface that has impurity is being carried out under the situation of precision work processing by the GCIB corrosion, only exist the treat surface of impurity partly to keep not being corroded, thereby cause waiting the problem that produces the convex defective on the treat surface of removing impurity by washing.
Acceleration voltage is 5～10keV more preferably.
Remove in second embodiment of method at impurity of the present invention, be selected from O in order under low etching condition, described treat surface to be implemented the GCIB corrosion, to use
2, Ar, B, CO
2, N
2O and hydroborons (BH for example
3And B
4H
10) at least a gas implement the GCIB corrosion as source gas.When this species of gases and treat surface bumped, it is initiating chamical reaction hardly, and a little less than the effect extremely on corrosion treatment surface.Using this species of gases to implement under the GCIB corrosive situation, can remove and be present in the impurity on the treat surface and can not handle described treat surface basically as source gas.
Remove in second embodiment of method at impurity of the present invention, the acceleration voltage that the species of gases that will have extremely weak corrosive nature is applied to accelerating electrode does not carry out particular restriction.Yet from being present in that impurity on the treat surface is removed and the viewpoint that can not handle described treat surface basically, preferred described acceleration voltage is more than the 15keV.Described acceleration voltage is more preferably more than the 20keV, more preferably more than the 30keV.Under the situation of acceleration voltage less than 15keV, when gas bunch and treat surface bumped, kinetic energy was little, therefore had the possibility that the impurity that is present on the treat surface can not be removed, and this depends on the size of impurity.Yet, even,, also the impurity that is present on the treat surface can be removed by adjustments of gas bunch size, dosage, irradiation time etc. when acceleration voltage during less than 15keV.
Impurity according to the present invention is removed aforementioned first embodiment and second embodiment of method, owing under low etching condition, described treat surface is implemented the GCIB corrosion, therefore can remove and can not handle described treat surface basically being present in impurity on the treat surface.The low etching condition of mentioning herein is preferably that etching extent is no more than the condition of 20nm, more preferably etching extent is no more than the condition of 10nm.
Remove in first embodiment and second embodiment of method at impurity of the present invention, according to the kind of source gas, be applied to the acceleration voltage of accelerating electrode etc., can suitably select radiation parameter, for example gas bunch size, be applied to and be used for the ionization electric current of the ionising electrode of the GCIB etching apparatus of described gas cluster ionization and the dosage of GCIB.Be to implement described GCIB corrosion under the condition more than 2000 preferably in gas bunch size.When described bunch size is 2000 when above,,, expection improves because of multiple collision effect so will being present in the effect that the impurity on the treat surface removes because big relatively gas bunch bumps with treat surface.Described bunch size more preferably more than 3000, is preferably more than 5000 especially.
Remove in first embodiment and second embodiment of method at impurity of the present invention, preferably from the direction that tilts with treat surface with GCIB irradiation to handling on the surface.When from the direction that tilts with treat surface with GCIB irradiation on described treat surface the time, expection will be present in the effect that the impurity on the treat surface removes and improve because of multiple collision effect.Fig. 1 is for showing from the direction that tilts with treat surface GCIB irradiation to the figure that handles lip-deep state.
In Fig. 1, preferably make normal N (therefore being the normal N of treat surface 10) remain 3～60 degree with the angle θ that the GCIB that incides treat surface 10 forms by glass substrate 1.By angle 9 is remained more than 3 degree, the effect that expection will be present in the impurity on the treat surface improves because of multiple collision effect.On the other hand, when angle θ being remained surpass 60 to spend, the some shape of the GCIB on treat surface obviously becomes ellipse.Therefore, when gas bunch and described treat surface bumped, kinetic energy disperseed, and will be present in the effect that the impurity on the treat surface removes thus and reduce.In addition, because the some shape of the GCIB on treat surface obviously becomes ellipse, the possibility of the Flatness deterioration of described treat surface after therefore existence enforcement GCIB corrodes.
Make angle θ keep 10～60 degree more preferably, more preferably 30～60 degree.
From the direction that tilts with treat surface with GCIB irradiation to handling under the lip-deep situation, as shown in fig. 1, under the states of treat surface 10 downward 3～60 degree with respect to horizontal direction, with GCIB with horizontal direction irradiation.According to this situation, not only will be present in the effect that the impurity on the treat surface removes and improve because of multiple collision effect, and, can stop the impurity of removing to be attached to again on the described treat surface.Described treat surface 10 is remained on respect to preferred downwards 10～60 degree of horizontal direction, more preferably under the states of 30～60 degree.
Treatment process of the present invention (1) comprises by the aforementioned impurity method of removing of the present invention will be present in the step (hereinafter, this step being called " impurity is removed step ") that the impurity on the glass substrate surface is removed; And handle the step (hereinafter, this step being called " treatment step ") of glass substrate surface by being selected from treatment process in the abrasion of ion beam etching, GCIB burn into plasma etching and nanometer.
Treat surface is being ground in advance so that have under the situation of predetermined Flatness and surfaceness, to be present in by the aforementioned impurity method of removing of the present invention after impurity on the treat surface removes, and treat surface is carried out precision work handle by being selected from treatment process in ion beam etching, GCIB burn into plasma etching and the nanometer abrasion.
In order after impurity is removed step, to stop new impurity to be attached on the treat surface, preferably same indoor or indoorly implement described impurity in such a way and remove step and described treatment step what place side by side, described mode makes it possible to transmit substrate and can not discharge in the slave unit.In treatment step, utilize under the GCIB corrosive situation, preferably remove and use identical GCIB etching apparatus in step and the described treatment step at described impurity.
In the aforementioned processing method, preferably use the GCIB corrosion, because can handle described surface so that have little surfaceness and excellent smoothness.
Utilizing under the GCIB corrosive situation, can use separately or use such as SF with the form of mixture
6, Ar, O
2, N
2, NF
3, N
2O, CHF
3, CF
4, C
2F
6, C
3F
8, C
4F
6, SiF
4And COF
2Gas as source gas.Wherein, from the viewpoint of the chemical reaction that when gas bunch bumps with treat surface, taken place, as source gas, SF
6, NF
3, CHF
3, CF
4, C
2F
6, C
3F
8, C
4F
6, SiF
4And COF
2For excellence.Particularly, in order to improve erosion rate and to improve and handle, preferably contain SF in section
6Or NF
3Mixed gas, be in particular SF
6And O
2Mixed gas, SF
6, Ar and O
2Mixed gas, NF
3And O
2Mixed gas, NF
3, Ar and O
2Mixed gas, NF
3And N
2Mixed gas, and NF
3, Ar and N
2Mixed gas.In this mixed gas, although the favourable ratio of mixture of various compositions is along with condition such as radiation parameter and change preferred following ratio of mixture.
SF
6/ O
2=0.1～5%/95～99.9% (SF
6And O
2Mixed gas)
SF
6/ Ar/O
2=0.1～5%/9.9～49.9%/50～90% (SF
6, Ar and O
2Mixed gas)
NF
3/ O
2=0.1～5%/95～99.9% (NF
3And O
2Mixed gas)
NF
3/ Ar/O
2=0.1～5%/9.9～49.9%/50～90% (NF
3, Ar and O
2Mixed gas)
NF
3/ N
2=0.1～5%/95～99.9% (NF
3And N
2Mixed gas)
NF
3/ Ar/N
2=0.1～5%/9.9～49.9%/50～90% (NF
3, Ar and N
2Mixed gas)
In these mixed gass, preferred SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3And O
2Mixed gas; And NF
3, Ar and O
2Mixed gas.
According to the kind of source gas, the surface properties of treat surface, the purpose that precision work is handled etc., can suitably select radiation parameter, for example gas bunch size, the ionization electric current of ionising electrode that is applied to the GCIB etching apparatus that is used for described gas cluster ionization and the dosage of GCIB.For example, for improve treat surface after pre-treatment Flatness and implement under the situation that precision work handles, the acceleration voltage that preferably is applied to accelerating electrode is for surpassing 15keV; The deterioration surfaceness within reason for the Flatness that improves treat surface, preferred acceleration voltage surpasses 15keV and is not more than 30keV.
In addition, in described treatment step,, must on treat surface, scan GCIB utilizing under the GCIB corrosive situation.As the method for scanning GCIB, gloss scanning and spiral scan are known, can use in these methods any one.
Treatment process of the present invention (2) comprises the step (hereinafter, this step being called " Flatness determination step ") of the Flatness of measuring glass substrate surface; The step (hereinafter, this step being called " impurity is removed step ") of the impurity on the treat surface being removed by the aforementioned impurity of the present invention method of removing; And the step of treat surface being handled by the treatment process that is selected from the abrasion of ion beam etching, GCIB burn into plasma etching and nanometer (hereinafter, this step is called " treatment step "), wherein in described treatment step, according to the result who obtains from the Flatness determination step, to the treatment condition of each set positions treat surface of treat surface.
In order to handle the treat surface of glass substrate, for example be used for EUVL mask glass substrate treat surface and denude by ion beam etching, GCIB burn into plasma etching or nanometer and to implement under the situation that pre-treatment and precision work handles, may have the situation that on described treat surface, has the part ripple after the pre-treatment.The ripple of mentioning herein is meant the irregular body that has 5～30mm cycle (cycle) in the periodicity irregular body on being present in treat surface.
Be difficult to remove this ripple so that on treat surface, have required Flatness by the precision work processing.In addition, also may exist in the ripple that produces in the pre-treatment grows into bigger ripple in the precision work treating processes situation.
Treatment process of the present invention (2) removes and described treat surface precision work is processed into the method on the surface with excellent Flatness for this ripple that will produce on treat surface after pre-treatment.
In treatment process of the present invention (2), for according to the result who obtains from the Flatness determination step and to the treatment condition of each set positions treat surface of treat surface, it is just better to implement the Flatness determination step before treatment step.Can after removing step, impurity implement described Flatness determination step.Yet, be attached on the treat surface in order after impurity is removed step, to stop new impurity, preferably before removing step, implements impurity described Flatness determination step.
In addition, in order after impurity is removed step, to stop new impurity to be attached on the treat surface, preferably same indoor or indoorly implement described impurity as follows and remove step and treatment step what place side by side, described mode makes it possible to transmit described substrate and can not discharge from described equipment.In treatment step, utilize under the GCIB corrosive situation, preferably remove and use identical GCIB etching apparatus in step and the treatment step at impurity.
In the Flatness determination step, the Flatness of measuring each position of treat surface is a difference of altitude.Therefore, the result who obtains from the Flatness determination step becomes the Flatness figure (hereinafter, it being called " Flatness figure ") of the difference of altitude of each position that is presented at treat surface.
Flatness in each position of described treat surface can for example be measured by laser interference type Flatness determinator.Yet, not should be understood to the present invention and be limited to this.Use laser displacement table, ultrasound displacement table or contact-type offset table, the measurement result of utilizing the difference of altitude of each position by measuring described treat surface to obtain can be prepared described Flatness figure.
In treatment process of the present invention (2), implementing after described Flatness determination step and impurity removes step, according to the treatment condition of the result who obtains from the Flatness determination step to each set positions treat surface of treat surface.
As previously mentioned, the result who obtains from the Flatness determination step becomes Flatness figure.(x under situation y), is expressed as S (x, y) (μ m) with Flatness figure being defined as the treat surface coordinate of two dimensional surface shape.To be expressed as T (x, y) (minute) treatment time.Under the situation that treatment rate is defined as Y (μ m/ minute), by the relation of following this tittle of The Representation Equation.
T(x，y)＝S(x，y)/Y
Therefore, under the basis situation of result that obtains from described Flatness determination step, according to aforementioned equation each set positions treatment condition, particularly treatment time to treat surface to the treatment condition of each set positions treat surface of treat surface.
In treatment step, utilizing with under the situation of the method for restrainting irradiation on the treat surface, particularly under the situation of utilizing ion beam etching, GCIB corrosion or plasma etching, according to the treatment condition of the result who obtains from the Flatness determination step to each set positions treat surface of treat surface.Specifically describe this setting program below.
Under the situation of implementing this setting program, the result that use obtains from the Flatness determination step stipulates to be present in the waviness width on the described treat surface.The waviness width of mentioning herein is meant the sunk part that periodically is present in the convex concave on the described treat surface or the length of bossing.Therefore, described waviness width is generally 1/2 of the described waviness width cycle.Have in existence under the situation of a plurality of ripples of different cycles, the waviness width that will have a minimum period is considered as being present in the waviness width on the described treat surface.
As previously mentioned, the measurement result that obtains from the Flatness determination step is the Flatness figure of difference of altitude of each position on display process surface.Therefore, can easily stipulate to be present in waviness width on the treat surface from Flatness figure.
According to the waviness width of stipulating in the aforementioned program, utilizing beam diameter is that the bundle that is no more than described waviness width is implemented ion beam etching, GCIB corrosion or plasma etching.The beam diameter of mentioning herein is based on FWHM (halfwidth) value.In this manual, when mentioning beam diameter, it is meant the FWHM value of beam diameter.In treatment step, more preferably using beam diameter is the bundle that is no more than waviness width 1/2.By using beam diameter to be no more than the bundle of waviness width, can be when concentrating on the ripple that is present on the treat surface irradiation beams, and effectively remove described ripple.
In treatment step, when utilizing when on described treat surface, restrainting the method for irradiation, promptly under the situation of utilizing ion beam etching, GCIB corrosion or plasma etching, must be on treat surface sweep beam.This is because for the treatment condition to each set positions treat surface of treat surface, requires to make once the scope with bundle irradiation as far as possible little.Especially, using beam diameter to be no more than under the situation of bundle of waviness width, must scan described treat surface with described bundle.As using the Shu Jinhang method for scanning, gloss scanning and spiral scan are known, can use in these methods any one.
In the aforementioned processing method, preferably use the GCIB corrosion, because can handle described surface so that have little surfaceness and excellent smoothness.
Utilizing under the GCIB corrosive situation, source gas and radiation parameter are with identical with radiation parameter about treatment process of the present invention (1) described source gas.
When implementing the treatment step of treatment process of the present invention (1) or (2), the surfaceness that may have a treat surface is the situation of deterioration a little, and this depends on the character of treat surface or the radiation parameter of bundle.In addition, may have following situation, even when can realize required Flatness in the aforementioned processing step time, can not handle described surface and have required surfaceness, this depends on the specification of glass substrate.Based on described reason, preferably afterwards, implement to be used to improve second treatment step of the surfaceness of treat surface in aforementioned processing step (hereinafter being called " first treatment step ").
In described second treatment step, can use the GCIB corrosion.In the case, by from being used for GCIB employed those condition changing radiation parameters of corrosion such as source gas, ionization electric current and the acceleration voltage that impurity is removed the GCIB corrosion of method and is used for first treatment step, implement the GCIB corrosion.Particularly, under making etching extent, implement the GCIB corrosion than the little radiation parameter of the etching extent of the GCIB that is used for first treatment step corrosion.Compare with the GCIB corrosion that is used for first treatment step, under the milder condition of using lower ionization electric current or lower acceleration voltage, implement the GCIB corrosion.More specifically, acceleration voltage is preferably more than the 3keV and less than 30keV, more preferably 3～20keV.In addition,, cause the viewpoint of chemical reaction hardly, preferably use independent O from when source gas and treat surface bump
2Gas or O
2Be selected from Ar, CO and CO
2In the mixed gas of at least a gas as source gas.Particularly, preferably use O
2Mixed gas with Ar.
In addition, in described second treatment step, can be at 1～60gf/cm
2Low surface pressure implement down to use the mechanical mill of grinding slurry, described mechanical mill to be called contact to grind.In contact is ground, between the abrasive sheet that has the grinding pad of making by non-woven fabrics, woven fabric etc. respectively, insert glass substrate, when having the slurry of predetermined character, make abrasive sheet rotate relatively through adjusting in supply with respect to glass substrate, thereby at 1～60gf/cm
2Surface pressure under described treat surface is carried out milled processed.
As grinding pad, for example, (Kanebo, Ltd.) the BELLATRIX K7512 of Zhi Zaoing is an available by Kanebo Ltd.As grinding slurry, the preferred grinding slurry that contains colloid silica that uses; More preferably use and contain the grinding slurry that average primary particle size is no more than colloid silica and the water of 50nm and has the pH in 0.5～4 scope through adjusting.The surface pressure that grinds is 1～60gf/cm
2When surface pressure surpasses 60gf/cm
2The time, owing on substrate surface, produce cut etc., therefore treat surface can not be handled to required surfaceness.In addition, exist the rotary load of abrasive sheet to become big possibility.When surface pressure less than 1gf/cm
2The time, it is long-time to handle cost, and therefore, this is actually disabled.In addition, when surface pressure less than 30gf/cm
2The time, it is long-time to handle cost.Therefore, preferably at 30～60gf/cm
2Surface pressure handle down after to a certain degree, at 1～30gf/cm
2Surface pressure under precision work carried out on the surface handled.
The average primary particle size of colloid silica is preferably less than 20nm, more preferably less than 15nm, is preferably less than 10nm especially.When the average primary particle size of colloid silica surpasses 50nm, be difficult to treat surface is handled and had a required surfaceness.In addition, from managing the viewpoint of described granularity arduously, the expectation colloid silica does not contain secondary granule as far as possible, and described secondary granule forms because of the primary granule coagulation.Contain at colloid silica under the situation of secondary granule, its mean particle size is preferably and is no more than 70nm.The granularity of the colloid silica of mentioning herein amplifies 15～105 * 10 for measuring by SEM (scanning electronic microscope)
3Image doubly and the granularity that obtains.
The content of the colloid silica in grinding slurry is preferably 10～30 quality %.When the content of colloid silica is less than 10 quality % in grinding slurry, there is the possibility of mill efficiency possible deviation, thereby can't realizes economic grinding.On the other hand, when the content of colloid silica surpassed 30 quality %, because the consumption of colloid silica increases, therefore there was the possibility of bringing problem in the viewpoint from cost and scourability.The content that grinds colloid silica in the slurry is 18～25 quality % more preferably, are preferably 18～22 quality % especially.
When the pH that grinds slurry is dropped in the aforementioned acid range, even when pH drops in 0.5～4 scope, can carry out chemistry and mechanical mill processing to treat surface, thereby with effective milled processed of good smoothness realization treat surface.That is to say that therefore the bossing of treat surface, can easily remove described bossing by mechanical mill by aching and limpization of grinding slurry.According to this situation, not only improved processing efficiency, and made that the glass waste of removing by milled processed is softening, therefore, stop the generation of the new damage that causes because of glass waste etc.When the pH that grinds slurry less than 0.5 the time, exist the shredder that is used for contacting grinding to produce the corrosive possibility.From the viewpoint of the handling property that grinds slurry, preferred pH is more than 1.In order to obtain sufficient chemical grinding treatment effect, preferred pH is preferably in 1.8～2.5 scopes especially for being no more than 4.
By adding mineral acid or organic acid separately or with its combination, can realize grinding the pH regulator of slurry.The representative examples of mineral pigments that can use comprises nitric acid, sulfuric acid, hydrochloric acid, perchloric acid and phosphoric acid.Wherein, consider and be convenient to handle, preferred nitric acid.In addition, the organic acid example comprises oxalic acid and citric acid.
As the water that is used for grinding slurry, preferred pure water or the ultrapure water of impurity having been removed that use.That is to say that overall dimension is that the above fine particle of 0.1 μ m is no more than one pure water or ultrapure water basically among preferred every ml, described overall dimension records by the scattering of light mode of using laser etc.When incorporating the quality that surpasses an impurity and do not consider material and shape among every ml into, be present in the possibility that forms surface imperfection such as scratch and hole on the treat surface.By for example filtering or ultrafiltration, the impurity in pure water or the ultrapure water can be removed, but the method for removing that not should be understood to impurity is limited to this with film filter.
In by treatment process of the present invention (1) or (2) handled glass substrate, treat surface has excellent Flatness and surfaceness; The Flatness of described treat surface is for being no more than 50nm after handling; And on described treat surface, there is not highly a glass convex defective that surpasses 1.5nm.After handling, the Flatness of described treat surface more preferably is no more than 30nm, more preferably is no more than 20nm.
Industrial applicibility
Glass substrate by disposal methods of the present invention is as being used for employed optics in the semi-conductor manufacturing exposure tool optical system, being no more than especially for line width in the semi-conductor manufacturing of 45nm that employed optics is favourable in the exposure tool optical system of future generation, because treat surface has excellent Flatness and surfaceness.The specific examples of this optics comprises lens, diffraction grating, optics film body and complex body thereof, for example lens, poly-lens, lens arra, biconvex lens, fly's-eye lens, non-spherical lens, speculum, diffraction grating, binary optical device, photomask and complex body thereof.
In addition, the glass substrate by disposal methods of the present invention is as photomask and be used to make the photoblank of this photomask, is favourable especially for the reflective mask of EUVL and the photoblank of making this mask.
The light source to exposure tool does not carry out particular restriction, and it can be for launching g-light (wavelength: 436nm) or the conventional laser device of i-light (wavelength 365nm).Yet preferred more short wavelength's light source is in particular the light source that wavelength is no more than 250nm.The specific examples of this light source comprises KrF excimer laser (wavelength: 248nm), ArF excimer laser (wavelength: 193nm), F
2Laser apparatus (wavelength: 157nm) and EUV (wavelength: 13.5nm).
Although at length and with reference to its specific embodiments described the present invention, to those skilled in the art, under the condition that does not deviate from the spirit and scope of the invention, it is conspicuous can finishing multiple variation and modification.
The application is Japanese patent application 2007-172274 number that submits to based on June 29th, 2007, and its content is incorporated herein by reference.
Claims (21)
1. method of removing impurity from glass substrate surface, described method comprises
Under the acceleration voltage of 5～15keV, described glass substrate surface is carried out the corrosion of gas ion beam.
2. method of removing impurity from glass substrate surface, described method comprises
With being selected from O
2, Ar, B, CO
2, N
2, N
2At least a gas in O and the hydroborons carries out the corrosion of gas ion beam as source gas to described glass substrate surface.
3. method of removing impurity from glass substrate surface as claimed in claim 1 or 2 wherein is not more than at etching extent and implements described gas ion beam corrosion under the condition of 20nm.
4. as each described method of removing impurity from glass substrate surface in the claim 1～3, wherein said glass substrate is that 0+30ppb/ ℃ low expansion glass is made by 20 ℃ thermal expansivity.
5. as each describedly removes the method for last impurity from glass substrate surface in the claim 1～4, wherein before implementing described gas ion beam corrosion, the surfaceness of described glass substrate surface (Rms) is for being not more than 5nm.
6. as each described method of removing impurity in the claim 1～5, wherein under being condition more than 2000, gas bunch size implements described gas ion beam corrosion from glass substrate surface.
7. as each described method of removing impurity from glass substrate surface in the claim 1～6, wherein when making the angle that forms by the normal of described glass substrate and the gas ion beam that incides described glass substrate surface remain 3～60 degree, implement described gas ion beam and corrode.
8. method of removing impurity from glass substrate surface as claimed in claim 7 wherein when making described glass substrate surface remain on respect to horizontal direction under downward 3～60 states of spending, is implemented described gas ion beam corrosion.
9. method of handling glass substrate surface, described method comprises the steps:
By each method in the claim 1～8 impurity on the described glass substrate surface is removed; And
Handle described glass substrate surface by the treatment process that is selected from ion beam etching, gas ion beam burn into plasma etching and the nanometer abrasion.
10. the method for processing glass substrate surface as claimed in claim 9, wherein said treatment process is the corrosion of gas ion beam.
11. the method for processing glass substrate surface as claimed in claim 10 is wherein surpassing under the acceleration voltage of 15keV, the gas ion beam of using mixed gas to implement in the described treatment step as source gas is corroded, and described mixed gas is selected from: SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3Sharp O
2Mixed gas; NF
3, Ar and O
2Mixed gas; NF
3And N
2Mixed gas; And NF
3, Ar and N
2Mixed gas.
12. the method for processing glass substrate surface as claimed in claim 11, wherein said source gas are to be selected from any one following mixed gas: SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3And O
2Mixed gas; And NF
3, the sharp O of Ar
2Mixed gas.
13. a method of handling glass substrate surface, described method comprises the steps:
Measure the Flatness of glass substrate surface;
By each method in the claim 1～8 impurity on the described glass substrate surface is removed; And
Handle described glass substrate surface by the treatment process that is selected from ion beam etching, gas ion beam burn into plasma etching and the nanometer abrasion,
Wherein in handling the step of described glass substrate surface, the result who obtains according to the step from described mensuration Flatness is to the treatment condition of each set positions glass substrate surface of described glass substrate.
14. the method for processing glass substrate surface as claimed in claim 13,
Wherein said treatment process is ion beam etching, the corrosion of gas ion beam or plasma etching,
Wherein according to the result who obtains from the step of described mensuration glass substrate surface Flatness, stipulate the waviness width that exists on the described glass substrate surface, and
Wherein with bundle described glass substrate surface is handled, the beam diameter with FWHM (halfwidth) value representation of described bundle is not more than described waviness width.
15. the method for processing glass substrate surface as claimed in claim 14, the FWHM value of wherein said beam diameter is for being not more than 1/2 of described waviness width.
16. the method for processing glass substrate surface as claimed in claim 15,
Wherein said treatment process is the corrosion of gas ion beam, and
Wherein surpassing under the acceleration voltage of 15keV, using mixed gas to implement described gas ion beam corrosion in the described treatment step as source gas, described mixed gas is to be selected from following any one: SF
6And O
2Mixed gas; SF
6, Ar and O
2Mixed gas; NF
3And O
2Mixed gas; NF
3, Ar and O
2Mixed gas; NF
3And N
2Mixed gas; And NF
3, Ar and N
2Mixed gas.
17. the method for processing glass substrate surface as claimed in claim 16, wherein said source gas are to be selected from any one following mixed gas: SF
6And O
2Mixed gas; SF
6, the sharp O of Ar
2Mixed gas; NF
3And O
2Mixed gas; And NF
3, Ar and O
2Mixed gas.
18. as the method for each described processing glass substrate surface in the claim 9～17, after the step of described processing glass substrate surface, described method also comprises second treatment step of the surfaceness that is used to improve described glass substrate surface.
19. the method for processing glass substrate surface as claimed in claim 18, wherein said second treatment step comprises: more than the 3keV and under the acceleration voltage less than 30keV, use independent O
2Gas or O
2Be selected from Ar, CO and CO
2In the gas ion beam corrosion carried out as source gas of the mixed gas of at least a gas.
20. the method for processing glass substrate as claimed in claim 18, wherein said second treatment step comprises: use to grind slurry and at 1～60gf/cm
2The mechanical mill implemented down of surface pressure.
21. a glass substrate that obtains by each method in the claim 9～20, wherein said substrate surface has the Flatness that is not more than 50nm, and does not have highly to surpass the convex glass defect of 1.5nm.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2007172274 | 2007-06-29 | ||
| JP172274/2007 | 2007-06-29 | ||
| PCT/JP2008/057553 WO2009004852A1 (en) | 2007-06-29 | 2008-04-11 | Method for removing foreign matter from glass substrate surface and method for processing glass substrate surface |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101687696A true CN101687696A (en) | 2010-03-31 |
Family
ID=39642873
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200880022677A Pending CN101687696A (en) | 2007-06-29 | 2008-04-11 | Method for removing foreign matter from glass substrate surface and method for processing glass substrate surface |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US20100101940A1 (en) |
| EP (1) | EP2170778A1 (en) |
| JP (1) | JP2009029691A (en) |
| KR (1) | KR20100032865A (en) |
| CN (1) | CN101687696A (en) |
| TW (1) | TW200902461A (en) |
| WO (1) | WO2009004852A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110227675A (en) * | 2018-03-06 | 2019-09-13 | 通用汽车环球科技运作有限责任公司 | The method of pollutant is optionally removed from optical component |
| CN111261498A (en) * | 2014-04-01 | 2020-06-09 | Ev 集团 E·索尔纳有限责任公司 | Method and device for treating a surface of a substrate |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5169163B2 (en) | 2006-12-01 | 2013-03-27 | 旭硝子株式会社 | Method for finishing a pre-polished glass substrate surface |
| JP5470703B2 (en) * | 2007-12-27 | 2014-04-16 | 旭硝子株式会社 | EUVL optical member and surface treatment method thereof |
| JP5490563B2 (en) | 2010-02-19 | 2014-05-14 | 東京エレクトロン株式会社 | Substrate cleaning method and substrate cleaning apparatus |
| JP2011173184A (en) * | 2010-02-23 | 2011-09-08 | Tokyo Electron Ltd | Polishing method |
| JP5236687B2 (en) * | 2010-05-26 | 2013-07-17 | 兵庫県 | Surface treatment method and surface treatment apparatus |
| JP5776397B2 (en) * | 2011-07-19 | 2015-09-09 | 東京エレクトロン株式会社 | Cleaning method, processing apparatus and storage medium |
| US8512586B2 (en) | 2011-09-01 | 2013-08-20 | Tel Epion Inc. | Gas cluster ion beam etching process for achieving target etch process metrics for multiple materials |
| US8557710B2 (en) | 2011-09-01 | 2013-10-15 | Tel Epion Inc. | Gas cluster ion beam etching process for metal-containing materials |
| US8513138B2 (en) | 2011-09-01 | 2013-08-20 | Tel Epion Inc. | Gas cluster ion beam etching process for Si-containing and Ge-containing materials |
| US8722542B2 (en) | 2012-06-08 | 2014-05-13 | Tel Epion Inc. | Gas cluster ion beam process for opening conformal layer in a high aspect ratio contact via |
| US8728947B2 (en) | 2012-06-08 | 2014-05-20 | Tel Epion Inc. | Gas cluster ion beam process for opening conformal layer in a high aspect ratio contact via |
| US20160004152A1 (en) * | 2013-02-25 | 2016-01-07 | Sean R. Kirkpatrick | Defect reduction in a substrate treatment method |
| US9209033B2 (en) | 2013-08-21 | 2015-12-08 | Tel Epion Inc. | GCIB etching method for adjusting fin height of finFET devices |
| KR102305099B1 (en) * | 2020-11-19 | 2021-09-27 | 한국기초과학지원연구원 | Mixed gas cluster ion beam generator and mass spectrometer comprising the same |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4278493A (en) * | 1980-04-28 | 1981-07-14 | International Business Machines Corporation | Method for cleaning surfaces by ion milling |
| US6808606B2 (en) * | 1999-05-03 | 2004-10-26 | Guardian Industries Corp. | Method of manufacturing window using ion beam milling of glass substrate(s) |
| US6368664B1 (en) * | 1999-05-03 | 2002-04-09 | Guardian Industries Corp. | Method of ion beam milling substrate prior to depositing diamond like carbon layer thereon |
| JP4207153B2 (en) * | 2002-07-31 | 2009-01-14 | 旭硝子株式会社 | Substrate polishing method and apparatus |
| JP4219718B2 (en) * | 2003-03-28 | 2009-02-04 | Ｈｏｙａ株式会社 | Manufacturing method of glass substrate for EUV mask blanks and manufacturing method of EUV mask blanks |
| JP4665443B2 (en) * | 2004-06-22 | 2011-04-06 | 旭硝子株式会社 | Glass substrate polishing method |
| EP1843985B1 (en) * | 2005-02-02 | 2012-06-06 | Asahi Glass Company, Limited | Process for polishing glass substrate |
| JP4548319B2 (en) * | 2005-02-02 | 2010-09-22 | 旭硝子株式会社 | Glass substrate polishing method |
| WO2006135098A1 (en) * | 2005-06-14 | 2006-12-21 | Asahi Glass Co., Ltd. | Method of finishing pre-polished glass substrate surface |
| JP4506689B2 (en) * | 2005-06-14 | 2010-07-21 | 旭硝子株式会社 | Method for finishing a pre-polished glass substrate surface |
| JP4997815B2 (en) * | 2006-04-12 | 2012-08-08 | 旭硝子株式会社 | Method for producing a highly flat and highly smooth glass substrate |
| JP5169163B2 (en) * | 2006-12-01 | 2013-03-27 | 旭硝子株式会社 | Method for finishing a pre-polished glass substrate surface |
-
2008
- 2008-04-11 EP EP08740610A patent/EP2170778A1/en not_active Ceased
- 2008-04-11 TW TW097113328A patent/TW200902461A/en unknown
- 2008-04-11 KR KR1020097027326A patent/KR20100032865A/en not_active Application Discontinuation
- 2008-04-11 WO PCT/JP2008/057553 patent/WO2009004852A1/en active Application Filing
- 2008-04-11 CN CN200880022677A patent/CN101687696A/en active Pending
- 2008-04-25 JP JP2008115127A patent/JP2009029691A/en not_active Withdrawn
-
2009
- 2009-12-29 US US12/648,481 patent/US20100101940A1/en not_active Abandoned
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111261498A (en) * | 2014-04-01 | 2020-06-09 | Ev 集团 E·索尔纳有限责任公司 | Method and device for treating a surface of a substrate |
| CN111326405A (en) * | 2014-04-01 | 2020-06-23 | Ev 集团 E·索尔纳有限责任公司 | Method and device for treating a surface of a substrate |
| CN110227675A (en) * | 2018-03-06 | 2019-09-13 | 通用汽车环球科技运作有限责任公司 | The method of pollutant is optionally removed from optical component |
Also Published As
| Publication number | Publication date |
|---|---|
| US20100101940A1 (en) | 2010-04-29 |
| TW200902461A (en) | 2009-01-16 |
| JP2009029691A (en) | 2009-02-12 |
| KR20100032865A (en) | 2010-03-26 |
| EP2170778A1 (en) | 2010-04-07 |
| WO2009004852A1 (en) | 2009-01-08 |
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Application publication date: 20100331 |