JP4118082B2 - Protective film repair method for photomask - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for correcting a protective film for a photomask, and more particularly to a method for correcting a protective film for a photomask such as a photoengraving original or a printed wiring board original which does not want to be mixed with fine dust.
[0002]
[Prior art]
Conventionally, in order to protect a photomask whose surface is easily damaged, a thin plastic film such as polyethylene terephthalate is used as a support, an adhesive or an adhesive is laminated on the plastic film, and a mold release is applied on the adhesive or the adhesive. A surface protective film formed by laminating films is used. Recently, a photomask, which is a manuscript used for photoengraving and a printed wiring board, has a complicated pattern to be created, and high resolution has been required. For this reason, a thinner protective film is required. However, in the surface protective film having the above-described structure, when the plastic film is further thinned, there is a problem that workability at the time of laminating on the photomask is deteriorated and wrinkles, bubbles and the like are easily generated.
[0003]
As a method for improving such a thing, for example, in Japanese Patent Application Laid-Open No. 2001-337443, a protective film transfer sheet for a photomask formed by sequentially laminating a protective layer and an adhesive layer from the peelable support side is used. A method for transferring a protective film to the image surface of a mask is described.
[0004]
[Problems to be solved by the invention]
And when sticking such a surface protection film or protective film transfer sheet to the image surface of the photomask, it is done in a clean environment so that foreign matters such as dust are not caught, but completely It is impossible to prevent foreign objects from being caught. In this way, if foreign matter is sandwiched between the photomask and the surface protective film or the transferred protective film, the foreign matter causes an exposure failure, so that the photomask itself becomes a defective product.
[0005]
When a surface protective film is used here, when such foreign matter is sandwiched, the attached surface protective film can be peeled off and reattached with a new one, but this increases the cost. . On the other hand, in the protective film transferred by the protective film transfer sheet, since the protective film is extremely thin, it is impossible to reattach the entire surface of the protective film after transfer.
[0006]
Accordingly, the present invention has been made to solve the above-described problems, and in order to prevent the photomask itself from becoming a defective product, the foreign matter caught in the transfer of the protective film for the photomask is removed. A method for correcting a protective film for a photomask that can partially correct the transferred protective film by removing and repairing the protective film by dropping a protective film repair solution for the photomask on the defective portion of the protective film. The purpose is to provide.
[0007]
[Means for Solving the Problems]
The method for correcting a protective film for a photomask according to the present invention, after the transfer of the protective film to the image surface of the photomask using a protective film transfer sheet for a photomask in which a protective film is provided on a peelable support, When transferring and adhering the protective film, sticking an adhesive member to the protective film part that is not adhered to the image surface because foreign matter has been sandwiched between the photomask and the protective film, After removing the foreign matter from the photomask together with the protective film portion not adhered to the image surface by peeling off the adhesive member, the photomask is applied to the lost portion of the protective film lost by peeling off the adhesive member. A repair film is formed by dripping a protective film repair solution.
[0008]
The method for correcting a protective film for a photomask according to the present invention includes the step of rubbing the adhesive tape when the adhesive member is an adhesive tape, and the adhesive tape is attached to a protective film portion not adhered to the image surface. By pressure bonding, cracks are generated at the end portions of the protective film portion not adhered to the image surface.
[0009]
In the method for correcting a protective film for a photomask according to the present invention, the adhesive member is removed from the photomask together with the protective film portion not adhered to the image surface by peeling off the adhesive member, and then the adhesive member is peeled off. By rubbing the lost portion of the protective film lost by removing the flash of the defective portion of the protective film, and then forming a repair film by dropping a protective film repair solution for photomask To do.
[0010]
The method for correcting a protective film for a photomask according to the present invention is characterized in that when a repair film is formed by dropping the protective film repair liquid for the photomask, a portion protruding from a defective portion of the protective film is removed. To do.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The photomask protective film correcting method of the present invention will be described with reference to FIGS.
[0012]
In the method for correcting a protective film for a photomask of the present invention, the protective film 2 is transferred and adhered to the image surface 11 of the photomask 1 using a protective film transfer sheet for a photomask in which a protective film is provided on a peelable support. Thereafter, when the protective film 2 is transferred and adhered, the foreign matter 3 is sandwiched between the photomask 1 and the protective film 2, so that the protective film portion 21 (FIG. 1) that is not adhered to the image surface 11 is attached. After removing the foreign material 3 from the photomask 1 together with the protective film portion 21 not adhered to the image surface 11 by applying an adhesive member (not shown) and then peeling off the adhesive member (FIG. 2), the adhesive member The protective film 41 is formed by dropping the protective film repair solution 4 for the photomask onto the defective portion 22 of the protective film lost by peeling off the film (FIG. 4).
[0013]
The protective film transfer sheet for a photomask used here is a sheet in which a protective film is provided on a peelable support, and a separator can be laminated on the protective film as necessary. . Here, the protective film is composed of at least a protective layer in direct contact with the support, and is preferably formed by laminating an adhesive layer on the protective layer as necessary.
[0014]
Here, the support is a base material when a protective film such as a protective layer or an adhesive layer is laminated, and has a function of transferring a thin protective film onto the image surface of the photomask with good workability. Here, since it is necessary for the support to be able to peel off the protective film, a release treatment such as providing a release layer on the surface is performed as necessary in order to improve the peelability of the protective film. It is preferable to use what was done.
[0015]
Here, the protective layer has an influence on the scratch resistance and solvent resistance of the protective film because the protective film comes to the outermost surface after being transferred to the image surface of the photomask. Therefore, in order to increase the scratch resistance and solvent resistance of the protective film, the protective layer is preferably formed from a material containing at least a thermosetting resin or an ionizing radiation curable resin.
[0016]
Furthermore, the adhesive layer provided as necessary is a layer that makes it easy to attach the photomask to the image surface. Adhesion to the photomask image surface and scratch resistance as a protective film can be achieved with only one protective layer. It is provided when it is difficult to achieve both solvent resistance. Further, in order to exhibit excellent scratch resistance and solvent resistance, it is preferable to increase the hardness of the adhesive layer itself. In order to increase the hardness of the adhesive layer as described above, the adhesive layer is also preferably made of at least a thermosetting resin or an ionizing radiation curable resin.
[0017]
The photomask in the present invention is one in which one surface of a substrate is an image surface. For example, the image surface is composed of an emulsion layer on which an exposure pattern is formed. Here, as the base material, those having good ionizing radiation transmittance are used, and for example, glass or plastic film is preferably used.
[0018]
As a means for transferring and adhering the protective film to the image surface of the photomask using such a photomask protective film transfer sheet, first, a protective layer of the photomask protective film transfer sheet or an adhesive provided as necessary Adhere the layer to the image side of the photomask. Then, after heating and / or ionizing radiation irradiation as necessary, the protective layer and / or the adhesive layer provided as necessary is cured to improve the adhesion to the image surface of the photomask, The protective film is transferred to the image surface of the photomask by peeling the support.
[0019]
Here, when the protective film 2 is transferred and adhered to the image surface 11 of the photomask 1 using the photomask protective film transfer sheet, the foreign matter 3 may be sandwiched between the photomask 1 and the protective film 2. (FIG. 1). Here, in the present invention, when the protective film 2 is transferred and adhered in this way, the foreign material 3 is sandwiched between the photomask 1 and the protective film 2 so that the protective film is not adhered to the image surface 11. A method of correcting the portion (hereinafter, referred to as a “protective film non-adhered portion”) 21 is provided.
[0020]
That is, according to the present invention, an operation is performed in which a pressure-sensitive adhesive member is attached to an unadhered portion of the protective film, and then the foreign material is removed from the photomask together with the non-adhered protective film portion by peeling off the pressure-sensitive adhesive member.
[0021]
The adhesive member used here is not particularly limited as long as it is a material having a surface that can be repeatedly applied and peeled by having at least partial adhesiveness, such as an adhesive tape or an adhesive roller. It can be used without
[0022]
In particular, when the adhesive member is an adhesive tape, it is preferable that the adhesive tape is pressure-bonded while being rubbed when the adhesive tape is attached to the non-adhered portion of the protective film. By pressure bonding while rubbing the adhesive tape in this way, cracks can be generated at the end of the non-adhered portion of the protective film, and it becomes easy to remove only the non-adhered portion of the protective film together with the foreign matter, and It is possible to make it difficult to cause the disadvantage that even the bonded protective film portion is removed.
[0023]
Here, the pressure bonding while rubbing means rubbing with a hard substance such as a nail or a spatula on the adhesive tape to prevent air from entering between the adhesive tape and the protective film. By crimping in this way, the effect of increasing the adhesive force between the pressure-sensitive adhesive tape and the protective film can be produced at the same time.
[0024]
As described above, when the protective film non-adhered portion is removed from the photomask 1 together with foreign substances by peeling off the adhesive member, a part of the protective film 2 covering the image surface 11 of the photomask 1 is lost. A defective portion 22 is generated in the protective film (FIG. 2). Hereinafter, the defective part of the protective film lost by peeling off the adhesive member in this way is simply referred to as “the defective part of the protective film”.
[0025]
Here, a “burr” 23 as shown in FIG. 2 may occur at the end of the defect 22 of the protective film. In such a case, it is preferable to remove the flash of the defective portion of the protective film by rubbing the defective portion of the protective film. This is because, by removing the flash of the defective portion of the protective film in this way, it is possible to make it difficult for the flash remaining in the whitened state to cause adverse effects such as generating scattered light during exposure and causing exposure failure. .
[0026]
At the time of rubbing, by using an organic solvent, the organic solvent soaks into only the gap portion floating as a flash, and only the flash can be removed without damaging the protective film portion bonded to the image surface. Specifically, rubbing can be performed by rubbing using a cotton swab or the like soaked with an organic solvent. In addition, as an organic solvent here, an alcohol type, a ketone type | system | group, an aromatic hydrocarbon type | system | group, an alcohol ester type | system | group, etc. can be used.
[0027]
Next, the repair film 41 is formed by dropping the protective film repair solution 4 for the photomask onto the defective portion 22 of the protective film (FIG. 3), whereby the correction of the protective film 2 can be completed. .
[0028]
As the photomask protective film repair solution used here, there can be used a solution containing at least a resin capable of forming a repair film and appropriately adding a diluent or an additive.
[0029]
The protective film repair solution for a photomask is required to be capable of adhering the formed repair film to the photomask. Here, from the viewpoint of developing adhesiveness to the photomask, the protective film repair solution for photomask contains a thermoplastic resin such as a thermoplastic polyester resin, a thermoplastic acrylic resin, or a vinyl acetate resin as a resin for forming the repair film. It is preferable to include.
[0030]
Moreover, it is preferable that the protective film repair liquid for photomasks is such that high scratch resistance and solvent resistance can be obtained as the performance of the repair film to be formed. That is, it is preferable that the repair film has the same performance as the protective film part adhered to the image surface.
[0031]
Here, as means for increasing the scratch resistance and solvent resistance, it is preferable to include at least a thermosetting resin or an ionizing radiation curable resin as the resin for forming the repair film.
[0032]
Here, as the thermosetting resin, those obtained by crosslinking and curing a crosslinkable resin such as silicone, melamine, epoxy, aminoalkyd, urethane, acrylic, polyester, and phenol by heat can be used. Among these, acrylic thermosetting resins having good light resistance and ionizing radiation transparency are preferably used. These can be used alone, but it is desirable to add a curing agent in order to further improve the crosslinkability and the hardness of the crosslinked cured coating film.
[0033]
Here, as the curing agent, a compound such as polyisocyanate, amino resin, epoxy resin, or carboxylic acid can be appropriately used in accordance with a suitable resin.
[0034]
In particular, it is desirable to use a curing agent that becomes a one-component curing reaction that causes a crosslinking reaction when heated to a certain temperature or higher without reacting at room temperature. As such a curing agent, a blocked isocyanate or the like using a method for blocking a catalyst or a functional group can be used.
[0035]
Here, the blocked isocyanate is a polyisocyanate masked with a masking agent, which does not react at room temperature and does not proceed with the curing reaction. When heated above the temperature at which the masking agent dissociates, an active isocyanate group is formed. It is regenerated and causes a sufficient crosslinking reaction. Further, since such a blocked isocyanate contains an isocyanate component, adhesion with the emulsion layer of the photomask is improved, and it can also play a role of improving the durability of the protective film.
[0036]
Polyisocyanate is obtained by polymerizing or copolymerizing an isocyanate monomer, and can be used without any particular limitation. Isocyanate monomers include 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 1,3- or 1,4-diisocyanate cyclohexane, m- or p-tetramethylxylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,12- Examples include dodecamethylene diisocyanate.
[0037]
The masking agent can be used without any particular limitation, for example, phenolic, alcoholic, active methylene, mercaptan, acid amide, acid imide, lactam, imidazole, urea, oxime, Examples thereof include amine-based, imide-based, and hydrazine compounds. Specifically, phenol, cresol, 2-hydroxypyridine, butyl cellosolve, propylene glycol monomethyl ether, ethylene glycol, benzyl alcohol, ethanol, diethyl malonate, ethyl acetoacetate, acetylacetone, butyl mercaptan, acetanilide, acetic acid amide, succinimide , Ε-caprolactam, imidazole, urea, thiourea, acetaldoxime, acetone oxime, cyclohexane oxime, diphenylamine, aniline, carbazole, ethyleneimine, dimethylhydrazine and the like.
[0038]
The dissociation temperature of the mask agent is preferably 100 ° C. or higher. Even when the diluted solvent is contained in the photomask protective film repair solution by setting the temperature to 100 ° C. or higher, the mask agent does not dissociate even if the diluted solvent is volatilized by heating at 100 ° C. or lower, Workability can be improved. However, when the photomask base material is inferior in heat resistance, such as a plastic film, the dissociation temperature of the mask agent is preferably 120 ° C. or lower. By setting the dissociation temperature of the mask agent to 120 ° C. or less, it is possible to prevent the photomask from being deteriorated in precision due to a dimensional change due to thermal shrinkage of the plastic film.
[0039]
In addition, as the ionizing radiation curable resin, it is preferable to use a resin formed from a paint that can be crosslinked and cured by irradiation with ionizing radiation (ultraviolet rays or electron beams). As such an ionizing radiation curable coating, one or a mixture of two or more of a photocationic polymerizable resin capable of photocationic polymerization, a photopolymerizable prepolymer or a photopolymerizable monomer capable of radical photopolymerization, and the like. Can be used.
[0040]
Examples of the photocationically polymerizable resin include epoxy resins such as bisphenol-based epoxy resins, novolac-type epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins, and vinyl ether-based resins.
[0041]
Examples of the photopolymerizable prepolymer include polyester (meth) acrylate, epoxy (meth) acrylate, urethane (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, and melamine (meth) acrylate. (Meth) acrylates can be used.
[0042]
Examples of the photopolymerizable monomer include styrene monomers such as styrene and α-methylstyrene, methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, methoxyethyl (meth) acrylate, (meth ) Butoxyethyl acrylate, butyl (meth) acrylate, methoxybutyl (meth) acrylate, phenyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, ethoxymethyl (meth) acrylate, (Meth) acrylic acid esters such as (meth) acrylic acid lauryl, unsaturated carboxylic acid amides such as (meth) acrylamide, (meth) acrylic acid-2- (N, N-diethylamino) ethyl, (meth) acrylic acid -2- (N, N-dibenzylamino) ethyl, (meth) acrylic acid-2- (N, N-diethylamino) propyl Substituted amino alcohol esters of unsaturated acids such as ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, nonaethylene glycol di ( (Meth) acrylate, polyethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, nonapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, pentaerythritol tri (Meth) acrylate, dipentaerythritol tri (meth) acrylate, pentaerythritol hexa (meth) acrylate, trimethylol pro Tri (meth) acrylate, glycerol tri (meth) acrylate, tris- (2-hydroxyethyl) -isocyanuric acid ester (meth) acrylate, 2,2-bis [4- (acryloxydiethoxy) phenyl] propane, 3- Polyfunctional compounds such as phenoxy-2-propanoyl acrylate, 1,6-bis (3-acryloxy-2-hydroxypropyl) -hexyl ether, and trimethylolpropane trithioglycolate, trimethylolpropane trithiopropylate, A polythiol compound having two or more thiol groups in a molecule such as pentaerythritol tetrathioglycolate can be used.
[0043]
In addition, various additives can be added to such an ionizing radiation curable coating. However, when ultraviolet rays are used for curing, it is preferable to add a photopolymerization initiator, an ultraviolet sensitizer or the like. As this photopolymerization initiator, photo radical polymerization initiators such as acetophenones, benzophenones, Michler ketone, benzoin, benzylmethyl ketal, benzoylbenzoate, α-acyloxime ester, thioxanthone, onium salts, sulfonate esters, organic Examples include photocationic polymerization initiators such as metal complexes, and examples of the ultraviolet sensitizer include n-butylamine, triethylamine, and tri-n-butylphosphine.
[0044]
In addition, a diluting solvent can be appropriately added to the photomask protective film repair solution as described above, but the diluting solvent that can be added here is particularly limited as long as it can dissolve the above-described resin. Can be used without Specific examples include ethyl acetate, butyl acetate, toluene, xylene, methyl ethyl ketone and the like. It is preferable to use a solvent having a low evaporation rate in order to obtain the leveling property of the liquid. By using a solvent having a low evaporation rate in this way, workability until the solvent volatilizes after dropping of the liquid can be improved. As such a diluting solvent, propylene glycol monomethyl ether, xylene, butyl acetate, cyclohexanone, or the like is used.
[0045]
In addition, an additive such as a leveling agent may be added to the photomask protective film repair solution as long as the above-described performance is not impaired.
[0046]
The various resins described above can be used alone, but several types can be mixed and used. For example, by using a mixture of a thermoplastic resin and an ionizing radiation curable resin, it is possible to form a repair film that has excellent adhesion to a photomask and that is particularly excellent in scratch resistance and solvent resistance. become.
[0047]
Next, as a means of dripping the protective film repair solution for photomasks, use a microsyringe needle or capillary tube to make a fine droplet, or drop the droplet attached to the tip of the needle to the defect. Or by dripping. Usually, since the area of the defective portion of the protective film is often very small, the inner diameter of, for example, a microsyringe needle or a capillary tube is desirably 200 μm or less. The thickness of the repair film can be adjusted by the amount of liquid droplets.
[0048]
In addition, as a means for forming a repair film from the photomask protective film repair solution dropped on the defective portion of the protective film, if the repair liquid contains a diluted solvent, the diluted solvent is volatilized, and the repaired film is also repaired. When the curable resin is contained in the resin forming the repair film included in the liquid, the repair film can be formed by curing the curable resin to form a film of the repair liquid.
[0049]
Thus, when forming a repair film by coating the protective film repair liquid for photomask, when the repair liquid dripped onto the defective part of the protective film protrudes from the defective part, it protrudes from the defective part. After removing the repair liquid, it is preferable to cure the curable resin or the like. In this way, by removing the repair liquid that protrudes from the defective portion, the repair film is not formed over the protective film to be corrected, and it is possible to make it difficult to cause unevenness in the thickness of the protective film. Thus, it is possible to make it difficult to cause an exposure failure due to deterioration of light transmittance or generation of scattered light.
[0050]
As a specific means for removing the repair liquid protruding from the defective portion, it can be performed by wiping with a cotton swab soaked with an organic solvent or the like. In addition, as an organic solvent here, an alcohol type, a ketone type | system | group, an aromatic hydrocarbon type | system | group, an alcohol ester type | system | group, etc. can be used.
[0051]
Further, as a means for curing the curable resin contained in the photomask protective film repair solution, when the curable resin uses a blocked isocyanate as a curing agent, it is heated above the temperature at which the mask agent is dissociated. To accelerate the curing reaction of the curable resin. Further, when the curable resin is an ionizing radiation curable resin, it can be cured by irradiating with ionizing radiation.
[0052]
Here, as a method of irradiating ionizing radiation (ultraviolet or electron beam), ultra-high pressure mercury lamp, high pressure mercury lamp, low pressure mercury lamp, carbon arc, xenon arc, metal halide lamp, etc. are used to irradiate ultraviolet rays, Cockloft Walton type, A method of irradiating an electron beam using various electron accelerators such as a van der graph type, a co-transformer type, an insulated core transformer type, a dynamitron type, and a high frequency type can be employed.
[0053]
【Example】
Examples of the present invention will be described below. “Part” and “%” are based on weight unless otherwise specified.
[0054]
[Example 1]
1. Production of protective film transfer sheet for photomask
A mold release layer coating liquid a having the following composition is applied to one surface of a polyethylene terephthalate film (T-600E: Mitsubishi Chemical Polyester Film Co., Ltd.) having a thickness of 50 μm, and dried to release a mold having a thickness of about 1 μm. A support provided with a layer was prepared.
[0055]
<Release layer coating solution a>
・ Polyvinyl methyl ether / maleic anhydride copolymer
(GANTREZ AN119: ISP) 50 copies
・ 414 parts of distilled water
・ Meta-modified alcohol 36 parts
[0056]
Next, a protective layer coating liquid b and an adhesive layer coating liquid c having the following composition are sequentially applied onto the release layer of the support and dried to thereby form a protective layer having a thickness of about 2 μm and a thickness of about 2 μm. The adhesive layer was laminated. At that time, the protective layer was dried and then cured by ultraviolet irradiation with a high-pressure mercury lamp. Further, a release treatment surface of a separator (ester film E7006: Toyobo Co., Ltd.) having a thickness of 38 μm was bonded onto the adhesive layer to obtain a protective film transfer sheet for a photomask.
[0057]
<Protective layer coating solution b>
・ Urethane acrylate (Unidic V4005 <Solid content
64%>: Dainippon Ink & Chemicals, Inc.) 125 parts
・ Photo radical polymerization initiator (Irgacure 184: Ciba
2.4 Charity Chemicals)
・ Toluene 275 parts
[0058]
<Coating liquid c for adhesive layer>
・ Photo cationic polymerizable resin (bisphenol A type epoxy)
resin <Product name: Adeka Optomer KRM-2410>: Asahi Denka
Industrial company) 1.5 parts
・ Photocationic polymerization initiator (triphenylsulfonium
salt <Product name: Adekaoptomer SP-170>: Asahi Denka Kogyo
Company) 0.1 part
・ Acrylic adhesive resin (SK Dyne 1102 <Solid content 40
%>: Soken Chemical Co., Ltd.)
・ 20 parts of ethyl acetate
・ Propylene glycol monomethyl ether 10 parts
[0059]
2. Transfer of protective film and removal of unbonded part of protective film
A laminator is used for the image surface on which the circuit pattern of the photomask having the circuit wiring pattern formed on the surface of the glass is formed by peeling the separator from the protective film transfer sheet for the photomask obtained above and exposing the adhesive layer. It was stuck by a heat roll heated to 100 ° C. Next, the adhesive layer was cured by irradiating ultraviolet rays with a high-pressure mercury lamp, and then the support was peeled off from the protective film, and the protective film was transferred and adhered to the image surface of the photomask.
[0060]
Next, since a foreign matter having a diameter of about 300 μm is sandwiched between the protective film transferred and adhered and the photomask image surface, the protective film is not adhered to the photomask image surface. A part was found, and a cellophane adhesive tape (CT-405A-18: Nichiban Co., Ltd.) was rubbed with a nail on the non-adhered part of the protective film, and pressed while causing cracks at the end of the non-adhered part of the protective film. Next, the adhesive tape was peeled off vigorously, and the protective film non-adhered portion was partially removed from the protective film together with foreign substances.
[0061]
3. Burr removal
When the defect portion of the protective film was observed, a burr was found on the defect portion. The burr was removed by rubbing with a cotton swab soaked with methyl ethyl ketone. The diameter of the defective portion of the protective film after the flash was removed was about 1 mm.
[0062]
4). Dropping of protective film repair solution for photomask and formation of repair film
A protective film repair solution d for the photomask having the following composition was dropped onto the defective portion of the protective film from which the flash had been removed.
[0063]
<Photomask protective film repair solution d>
・ Thermoplastic acrylic resin (LMS-55 <Solid content 40%>
Chemical Industry Co., Ltd.) 25 parts
・ Urethane acrylate (Unidic 17-824-9 <Solid
Min. 80%>: Dainippon Chemical Co., Ltd.) 12.5 parts
・ Methyl ethyl ketone 180 parts
・ 180 parts of propylene glycol monomethyl ether
[0064]
The part of the photomask protective film dripped here that protrudes from the defective part of the protective film was wiped off with a cotton swab soaked with methyl ethyl ketone. The diluted solvent in the repair solution was evaporated and dried at 80 ° C. for 3 minutes, and then irradiated with ultraviolet light with a high-pressure mercury lamp to cure the dripped repair solution to form a repair film.
[0065]
In addition, when dropping, a capillary with an inner diameter of about 70 μm is used, and the amount of the dropped liquid is set to about 0.5 μl, so that the thickness of the formed repair film is about the same as that of the surrounding protective film. became.
[0066]
[Example 2]
1. Production of protective film transfer sheet for photomask
A photomask protective film transfer sheet was obtained in the same manner as in Example 1 except that the following adhesive layer coating solution e was used instead of the adhesive layer coating solution c of Example 1.
[0067]
<Coating liquid e for adhesive layer>
・ Thermosetting acrylic resin (Acridic A-814 <Solid
50%>: Dainippon Ink & Chemicals, Inc.) 10 parts
・ Block isocyanate curing agent (DB-980K <7 solids
5%>: Dainippon Ink & Chemicals, Inc., masking agent dissociation temperature
Degree: 130 ° C) 0.86 parts
・ Acrylic adhesive resin (SK Dyne 1102 <Solid content 40
%>: Soken Chemical Co., Ltd.) 20 copies
・ 50 parts of ethyl acetate
・ Methyl ethyl ketone 50 parts
・ Propylene glycol monomethyl ether 100 parts
[0068]
2. Transfer of protective film and removal of unbonded part of protective film
After the protective film transfer sheet for the photomask is adhered to the image surface of the photomask, when the adhesive layer is cured, instead of irradiating with ultraviolet rays, the block isocyanate masking agent is dissociated by heating at 140 ° C. for 180 minutes. The protective film was transferred and adhered in the same manner as in Example 1 except that the adhesive layer was cured, and the non-adhered portion of the protective film was removed.
[0069]
3. Burr removal
In the same manner as in Example 1, the flash generated on the defects in the defect portion was removed.
[0070]
4). Dropping of protective film repair solution for photomask and formation of repair film
Instead of dripping a protective film f for a photomask protective film f having the following composition on the defective part of the protective film from which the burrs have been removed and irradiating it with ultraviolet rays as a curing means, heating is performed at 140 ° C. for 180 minutes to block the blocked isocyanate. A repair film was formed in the same manner as in Example 1 except that the repair solution was cured by dissociating.
[0071]
<Photomask protective film repair solution f>
・ Thermoplastic acrylic resin (LMS-55 <Solid content 40%>
Chemical Industry Co., Ltd.) 10 parts
・ Thermosetting acrylic resin (Acridic A-814 <Solid
50%>: Dainippon Ink & Chemicals, Inc.) 10 parts
・ Block isocyanate curing agent (DB-980K <7 solids
5%>: Dainippon Ink & Chemicals, Inc., masking agent dissociation temperature
Degree: 130 ° C) 0.86 parts
・ Methyl ethyl ketone 110 parts
・ 110 parts of propylene glycol monomethyl ether
[0072]
In both the first and second embodiments, the foreign matter sandwiched between the protective film transferred from the photomask protective film transfer sheet and the photomask image surface can be easily removed together with the protective film non-adhered portion. It is possible to form a repair film on the defective portion of the protective film by dropping the protective film repair solution for photomask into the defective portion of the protective film, and to easily correct the protective film after transfer It was possible.
[0073]
【The invention's effect】
According to the photomask protective film correcting method of the present invention, even when foreign matter is caught when transferring and adhering the photomask protective film, the foreign matter is removed and the foreign matter is removed. By forming a repair film by dripping a protective film repair solution for the photomask on the defective part of the protective film that occurs during removal, the transferred protective film can be partially corrected, so the photomask itself is not defective. It can be prevented from becoming a non-defective product.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a state in which foreign matter has been sandwiched between a photomask and a protective film.
FIG. 2 is a cross-sectional view showing a state in which a non-adhered portion of the protective film is removed from the image surface of the photomask and a defective portion is generated in the protective film.
FIG. 3 is a cross-sectional view showing a state in which a protective film repair solution for a photomask is dropped on a defective portion of the protective film on the image surface of the photomask.
FIG. 4 is a cross-sectional view showing a state in which a repair film is formed on a defect portion of the protective film on the image surface of the photomask.
[Explanation of symbols]
1 ... Photomask
11. Image plane
2 ... Protective film
21 ... Protective film non-bonded part
22 ... Defects in protective film
23 ... Bari
3 ... Foreign matter
4 .... Protective film repair solution for photomask
41 ... repair film

Claims (4)

When the protective film is transferred and bonded to the image surface of the photomask using a protective film transfer sheet for a photomask having a protective film provided on a peelable support, the photomask is transferred and bonded. Adhesive member is attached to the protective film portion that is not adhered to the image surface because foreign matter has been sandwiched between the protective film and the protective film, and then adhered to the image surface by peeling off the adhesive member After removing the foreign matter from the photomask together with the protective film portion that has not been removed, a repair film by dropping a protective film repair solution for the photomask onto the defective portion of the protective film that has been lost by peeling off the adhesive member A method for correcting a protective film for a photomask, comprising: forming a mask. The method for correcting a protective film for a photomask according to claim 1, wherein the adhesive member is an adhesive tape, and the adhesive tape is rubbed when the adhesive tape is attached to a protective film portion not adhered to the image surface. A method for correcting a protective film for a photomask, comprising: cracking the edge of the protective film part not adhered to the image surface by pressure bonding. 2. The photomask protective film correcting method according to claim 1, wherein the foreign material is removed from the photomask together with the protective film portion not adhered to the image surface by peeling off the adhesive member, and then the adhesive member is pulled. By rubbing the defective part of the protective film lost by peeling, the flash of the defective part of the protective film is removed, and then a protective film is formed by dropping a protective film repair solution for photomask. A method for correcting a protective film for a photomask. 2. The method for correcting a protective film for a photomask according to claim 1, wherein when the repair film is formed by dripping the protective film repair liquid for the photomask, a portion protruding from the defective portion of the protective film is removed. A method for correcting a protective film for a photomask.

Images