Adhesive for pellicle, pellicle, exposed master plate with pellicle, manufacturing method for semiconductor device, manufacturing method for liquid crystal display panel, recycling method for exposed master plate, and method for reducing peeling residue

Abstract

To provide a pellicle adhesive whereby, when a pellicle is peeled from an exposure master plate after use in lithography, particularly after use in ArF lithography, residues stuck on the exposure master plate can be reduced, and provide a pellicle, an exposure master plate with a pellicle, an exposure master plate regeneration method and a peeling residue reduction method.SOLUTION: A pellicle adhesive for attaching a pellicle to an exposure master plate, the pellicle adhesive containing a polyvinyl ether compound.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an adhesive for a pellicle, a pellicle, an exposed master plate with a pellicle, a method for manufacturing a semiconductor device, a method for manufacturing a liquid crystal display panel, a method for recycling an exposed master plate, and a method for reducing peeling residue. [Background technology]

[0002] In the manufacture of semiconductor devices such as LSI and VLSI, or liquid crystal display panels, a pattern is created by irradiating a semiconductor wafer or a liquid crystal master with light, but if dust is attached to the exposure master used in this case, the dust absorbs or bends the light, causing problems such as deformation of the transferred pattern, rough edges, and black staining of the base, impairing dimensions, quality, appearance, etc. In this invention, "exposure master" is a general term for lithography masks and reticles.

[0003] These operations are usually carried out in a clean room. However, since it is difficult to keep the exposure master clean even in this clean room, a method is used in which a pellicle that allows exposure light to easily pass through is attached to the surface of the exposure master to keep out dirt. In this case, the dust does not adhere directly to the surface of the exposure master, but adheres to the pellicle film. Therefore, if the focus is aligned on the pattern of the exposure master during lithography, the dust on the pellicle film will not affect the transfer.

[0004] The basic structure of a pellicle is a pellicle frame and a pellicle film stretched over it. The pellicle film is made of nitrocellulose, cellulose acetate, fluoropolymer, etc., which transmits light used for exposure (g-line, i-line, 248 nm, 193 nm, 157 nm, etc.) well. The pellicle frame is made of aluminum alloys such as A7075, A6061, A5052, stainless steel, polyethylene, etc., which have been subjected to black anodizing treatment. A good solvent for the pellicle film is applied to the upper part of the pellicle frame, and the pellicle film is air-dried and bonded, or is bonded with an adhesive such as acrylic resin, epoxy resin, or fluororesin. In addition, since the exposure master plate is attached to the lower part of the pellicle frame, an adhesive layer made of polybutene resin, polyvinyl acetate resin, acrylic resin, silicone resin, etc., and a protective liner for protecting the adhesive layer are provided.

[0005] The pellicle is installed so as to surround the pattern area formed on the surface of the exposure master. The pellicle is provided to prevent dust from adhering to the exposure master, and therefore this pattern area is isolated from the outside of the pellicle so that dust outside the pellicle does not adhere to the pattern surface.

[0006] In recent years, LSI design rules have been miniaturized to the sub-quarter micron level, and as a result, exposure light sources are becoming shorter in wavelength, that is, they are shifting from the previously mainstream g-line (436 nm) and i-line (365 nm) from mercury lamps to KrF excimer lasers (248 nm), ArF excimer lasers (193 nm), F2 lasers (157 nm), etc. As a result of miniaturization, the allowable size of foreign matter and haze that may occur on the pattern surface of a mask substrate to which a pellicle is attached is becoming increasingly strict. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 5638693 [Patent Document 2] JP 2016-18008 A [Patent Document 3] JP 2006-146085 A [Patent Document 4] JP 2008-21182 A Summary of the Invention [Problem to be solved by the invention]

[0008] In recent years, phase shift films have become the norm for mask substrates in order to keep up with the miniaturization of design rules. However, phase shift films are very delicate, and mask cleaning under excessive conditions can cause damage such as corrosion or scraping. For this reason, there has been a trend in recent years to reconsider the chemicals used for mask cleaning and to weaken the cleaning conditions.

[0009] Furthermore, advanced masks are shifting from the previously mainstream positive type mask patterns to negative type mask patterns, and as a result, there are many cases where there is no light-shielding layer in the area where the pellicle is attached. Without the light-shielding layer, there is a possibility that the exposure light will be irradiated onto the pellicle adhesive through the mask substrate. This may result in more residue of the adhesive layer remaining on the mask substrate when the pellicle is peeled off.

[0010] When a pellicle is attached to a mask for use, if foreign matter or haze occurs or the pellicle film is damaged, the pellicle must be peeled off, the mask regenerated and cleaned, and replaced with a new pellicle (hereinafter, this will be referred to as a "repellicle"). The most important thing about a repellicle is to regenerate and clean the mask to a high degree of cleanliness, but in order to regenerate and clean the mask under recent weak cleaning conditions, it is important to minimize the residue remaining on the mask substrate when the pellicle is peeled off. This regeneration cleaning generally involves cleaning with chemicals such as sulfuric acid / hydrogen peroxide or ammonia / hydrogen peroxide, or physical cleaning using brushes, sponges, etc. However, in order to prevent damage to the photomask and to prevent sulfate ions from remaining on the photomask, regeneration cleaning using functional water has been considered.

[0011] Functional water is generally defined as an aqueous solution that has been given a reproducible and useful function by artificial processing, and the scientific basis of the processing and function has been clarified or is about to be clarified.Specific examples include ozone water, hydrogen water, fine bubble water such as microbubble water and nanobubble water, electrolytic water, supercritical water, and subcritical water, and ozone water and hydrogen water are often used to clean photomasks.In addition, the cleaning power can be improved by adding a small amount of ammonia.

[0012] However, the inventors have found that functional water has a weaker cleaning power than chemicals such as sulfuric acid / hydrogen peroxide, and therefore, when cleaning a photomask after peeling off a pellicle, the residue of the adhesive layer that fixed the pellicle and the photomask is difficult to remove by cleaning with functional water alone. In particular, in the case of a phase shift photomask, damage to the phase shift film leads to changes in transmittance and phase difference, so it is difficult to add physical cleaning in addition to cleaning with functional water.

[0013] Furthermore, when lithography is performed using exposure light such as an ArF excimer laser (193 nm) with a lithography pellicle in which a pellicle film is attached to the upper end surface of the pellicle frame via an adhesive layer for attaching the pellicle film, and an adhesive layer for attaching a mask is provided on the other end surface, the adhesive layer formed on the lower end surface of the pellicle frame is altered by the exposure light, and when it is peeled off from the exposed master, the altered parts of the adhesive layer remain on the exposed master as peeling residue, which is a problem.

[0014] To date, attempts have been made to reduce residue by adding surface modifiers to the adhesive (see Patent Documents 1 and 2). 2Disclosed are a large pellicle having an adhesive layer having the above structure (Patent Document 3), and a pellicle having an adhesive for a pellicle having a ratio of peel strength to tensile strength of 0.10 or more and 0.33 or less (Patent Document 4).

[0015] The present invention has been made in view of the above circumstances, and aims to provide a pellicle adhesive, a pellicle, an exposed master with a pellicle, a method for regenerating an exposed master, and a method for reducing residues left behind after peeling, which are capable of reducing residues left on an exposed master when the pellicle is peeled off from the exposed master after use in lithography, particularly after use in ArF lithography, and thereby to provide a method for manufacturing a semiconductor device and a liquid crystal display panel that can improve production efficiency. [Means for solving the problem]

[0016] The above-mentioned problems of the present invention have been solved by the following means. [1] A pellicle adhesive for attaching a pellicle to an exposure master, comprising: An adhesive for a pellicle comprising a polyvinyl ether compound. [2] The adhesive for pellicles described in [1] above, wherein the polyvinyl ether compound is a polymer having vinyl ethers as monomer components, or a polymer having vinyl ethers and monomers copolymerizable with vinyl ethers as polymerization components. [3] The adhesive for pellicles according to [2] above, wherein the vinyl ether is at least one selected from the group consisting of methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether and (2-methoxyethyl) vinyl ether. [4] The pressure-sensitive adhesive for a pellicle according to any one of [1] to [3] above, further comprising at least one selected from the group consisting of an acrylic polymer, a silicone resin, and a thermoplastic elastomer. [5] The adhesive for pellicles according to any one of [1] to [3], further comprising an acrylic polymer, wherein the content of the polyvinyl ether compound is 0.5 to 10 parts by mass per 100 parts by mass of the solid content of the acrylic polymer. [6] The adhesive for pellicles according to [4] or [5], wherein the acrylic polymer comprises a (meth)acrylic acid ester having an ether bond as a monomer component. [7] The adhesive for pellicles according to [6], wherein the (meth)acrylic acid ester having an ether bond is a (meth)acrylic acid ester having an alkylene oxide group. [8] The adhesive for pellicles according to [7] above, wherein the alkylene oxide group is an ethylene oxide group. [9] The pressure-sensitive adhesive for pellicles according to [4] or [5], wherein the acrylic polymer has a side chain containing an ether bond.

[10] The adhesive for pellicles described in [9], wherein the side chain containing an ether bond has an alkylene oxide group.

[11] The adhesive for pellicles according to

[10] above, wherein the alkylene oxide group is an ethylene oxide group.

[12] A pellicle frame with an adhesive layer, comprising: a pellicle frame; and an adhesive layer obtained from the adhesive for a pellicle described in any one of [1] to

[11] provided on one end surface of the pellicle frame.

[13] A pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface thereof, and an adhesive layer obtained from the adhesive for a pellicle described in any one of [1] to

[11] provided on the other end surface of the pellicle frame.

[14] The pellicle according to

[13] , wherein the adhesive layer is irradiated with an exposure light beam.

[15] The pellicle according to

[13] above, which is attached to a phase shift photomask.

[16] The pellicle according to

[13] above, which is attached to a negative type exposure master plate.

[17] The pellicle according to

[13] above, which is attached to an exposure master having a non-light-shielding area or a semi-transparent light-shielding area in the area where the adhesive layer is attached.

[18] The pellicle according to

[13] above, which is attached to an exposure master having a transparent area at the attachment portion of the adhesive layer in the exposure master.

[19] The pellicle according to

[13] above, which is attached to a surface mainly composed of silicon oxide.

[20] The pellicle according to

[19] , wherein the surface mainly composed of silicon oxide is a quartz surface.

[21] The pellicle according to

[13] above, which is suitable for regeneration and cleaning using functional water.

[22] An exposure master with a pellicle, comprising the pellicle described in

[13] or

[14] attached to the exposure master.

[23] The exposure master with a pellicle according to the above

[22] , wherein the exposure master is a phase shift photomask.

[24] The exposure master with a pellicle according to the above

[22] , wherein the exposure master is of a negative type.

[25] An exposure master with a pellicle according to the above

[22] , wherein the adhesive layer of the exposure master has an area that is not light-shielded or a semi-transparent light-shielded area in the area to which the adhesive layer is attached.

[26] The exposure master with a pellicle according to

[22] above, wherein the adhesive layer of the exposure master has a transparent area attached thereto.

[27] The exposure master with a pellicle according to

[22] , wherein the exposure master is mainly composed of silicon oxide.

[28] The exposure master with a pellicle according to

[22] above, wherein the exposure master is a quartz substrate.

[29] A method for manufacturing a semiconductor device, comprising a step of exposing using an exposure master with a pellicle according to any one of

[22] to

[28] above.

[30] A method for producing a liquid crystal display panel, comprising a step of exposing using an exposure master with a pellicle according to any one of

[22] to

[28] above.

[31] A method for regenerating an exposed master, comprising peeling off the pellicle from the pellicle-attached exposed master described in any one of

[22] to

[28] above, and washing off any adhesive residue remaining on the exposed master with functional water, thereby regenerating the exposed master.

[32] A method for reducing the residue of an adhesive layer of a pellicle remaining on an exposure master when the pellicle is peeled off from an exposure master to which the pellicle is affixed, the method using a pellicle described in any one of

[13] to

[21] as the pellicle.

[33] An application of a pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface thereof, and an adhesive layer obtained from the pellicle adhesive provided on the other end surface of the pellicle frame, wherein the adhesive layer is exposed to exposure light.

[34] An application of a pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface, and an adhesive layer obtained from the pellicle adhesive provided on the other end surface of the pellicle frame, the application of the pellicle being attached to a phase shift photomask.

[35] An application of a pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface, and an adhesive layer obtained from the pellicle adhesive provided on the other end surface of the pellicle frame, the application of the pellicle being attached to a negative-type exposure master plate.

[36] An application of a pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface, and an adhesive layer obtained from the pellicle adhesive provided on the other end surface of the pellicle frame, wherein the pellicle is attached to an exposed master having a non-light-shielded area or a translucent light-shielded area in the adhesive layer attachment portion of the exposed master.

[37] An application of a pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface, and an adhesive layer obtained from the pellicle adhesive provided on the other end surface of the pellicle frame, wherein the pellicle is attached to an exposed master having a transparent area in the attachment portion of the adhesive layer on the exposed master.

[38] An application of a pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface, and an adhesive layer obtained from the pellicle adhesive provided on the other end surface of the pellicle frame, the application of the pellicle being attached to a surface primarily composed of silicon oxide (particularly a quartz surface).

[39] An application of a pellicle having a pellicle membrane, a pellicle frame having the pellicle membrane provided on one end surface, and an adhesive layer obtained from the pellicle adhesive provided on the other end surface of the pellicle frame, the application of the pellicle being compatible with regeneration and cleaning using functional water.

[40] A peeling residue-reducing pellicle comprising a pellicle film, a pellicle frame with the pellicle film attached to one end surface thereof, and an adhesive layer provided on the other end surface of the pellicle frame for attaching the pellicle to an exposure master, wherein the adhesive layer is formed from a composition containing an acrylic resin and a polyvinyl ether compound.

[41] The pellicle having reduced peeling residue according to

[40] above, wherein the composition according to

[40] above contains 0.5 to 10 parts by mass of a polyvinyl ether compound per 100 parts by mass of the solid content of the acrylic resin.

[42] The pellicle having reduced peeling residue according to

[40] or

[41] above, which is a pellicle having reduced peeling residue for ArF lithography.

[43] A method for producing a pellicle with reduced peeling residue, comprising forming an adhesive for attaching a pellicle to an exposure master from a composition containing an acrylic resin and a polyvinyl ether compound, applying the adhesive to one end surface of a pellicle frame to form an adhesive layer, removably attaching a protective member to the adhesive layer, and applying an adhesive to the other end surface of the pellicle frame and attaching a pellicle film to the adhesive layer.

[44] The method for producing a pellicle with reduced peeling residue according to

[43] above, wherein the composition contains 0.5 to 10 parts by mass of a polyvinyl ether compound per 100 parts by mass of the solid content of the acrylic resin.

[45] A method for reducing the peeling residue of an adhesive layer of a pellicle remaining on an exposure master when the pellicle is peeled off from an exposure master to which the pellicle is affixed, the method being characterized in that a pellicle described in any one of

[40] to

[42] above is used as the pellicle. Effect of the Invention

[0017] According to the present invention, when a pellicle is peeled off from an exposed master after lithography, particularly after ArF lithography, it is possible to provide a pellicle adhesive, a pellicle, an exposed master with a pellicle, a method for regenerating an exposed master, and a method for reducing peeling residue, which can reduce the peeling residue of the adhesive layer of the pellicle remaining on the exposed master. The pellicle, the exposed master with a pellicle, the method for regenerating an exposed master, and the method for reducing peeling residue of the pellicle of the present invention can peel off the pellicle from the exposed master with very little peeling residue of the adhesive even if the exposure light is irradiated through the exposed master. As a result, the regeneration cleaning of the exposed master from which the pellicle has been peeled off can be carried out well, and furthermore, it is possible to alleviate the cleaning conditions, which is advantageous in terms of reducing damage to the exposed master surface during cleaning. In addition, it is possible to improve the production efficiency in the manufacture of semiconductor devices and liquid crystal display panels. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a conceptual diagram showing the basic structure of a pellicle of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The basic structure of the pellicle of the present invention will first be described with reference to FIG.

[0020] 1, the pellicle 10 of the present invention comprises a pellicle film 12 stretched over the upper end surface of a pellicle frame 11 via an adhesive layer 13 for attaching the pellicle film, and in this case, an adhesive layer 14 for adhering the pellicle 10 to an exposure master (mask substrate or reticle) 1 is usually formed on the lower end surface of the pellicle frame 11, and a liner (not shown) is releasably attached to the lower end surface of the adhesive layer 14. The pellicle frame 11 may also be provided with an air pressure adjustment hole (vent) 15, and may further be provided with a dust filter 16 for the purpose of removing particles.

[0021] In this case, the size of these pellicle components is similar to that of ordinary pellicles, such as pellicles used in semiconductor lithography and pellicles used in the lithography process of manufacturing large liquid crystal display panels, and the materials thereof can be the well-known materials as described above.

[0022] The type of pellicle film 12 is not particularly limited, and for example, an amorphous fluoropolymer that has been conventionally used for excimer lasers may be used. Examples of amorphous fluoropolymers include Cytop (trade name of Asahi Glass Co., Ltd.), Teflon (registered trademark) AF (trade name of DuPont Co., Ltd.), etc. These polymers may be dissolved in a solvent as necessary when preparing the pellicle film, and can be appropriately dissolved in, for example, a fluorine-based solvent.

[0023] The base material of the pellicle frame 11 may be, for example, a conventionally used aluminum alloy material, preferably JIS A7075, JIS A6061, or JIS A5052 material, but there is no particular restriction on the aluminum alloy material as long as the strength of the pellicle frame is ensured. The surface of the pellicle frame is preferably roughened by sandblasting or chemical polishing, and a polymer coating may be provided after roughening. In the present invention, the method of roughening the frame surface may be a conventionally known method. A method of roughening the surface of an aluminum alloy material by blasting the surface with stainless steel, carborundum, glass beads, or the like, and then chemically polishing the surface with NaOH or the like is preferable.

[0024] Meanwhile, the inventors of the present invention have conducted extensive research and experiments in order to solve the above-mentioned problems of the present invention, focusing in particular on the characteristics of the adhesive that forms the adhesive layer, and have comparatively analyzed the experimental results, and have found that the following measures are effective.

[0025] That is, by incorporating a polyvinyl ether compound into the adhesive for attaching the pellicle to the exposed master, it is possible to reduce the peeling residue of the adhesive layer remaining on the exposed master when the pellicle is peeled off from the exposed master. In addition, even if the adhesive layer is irradiated with exposure light (for example, ultraviolet light of 193 nm) during use of the pellicle, peeling residue is easily suppressed. As a result, not only does the regeneration cleaning of the mask substrate from which the pellicle has been peeled off proceed smoothly, but it is also possible to alleviate the cleaning conditions, which is advantageous in reducing damage to the mask surface during cleaning. Although the function of reducing peeling residue is not clear, it is presumed that by incorporating a polyvinyl ether compound into the adhesive, it is possible to easily control the hydrophilicity of the adhesive and improve the cohesive force of the adhesive.

[0026] Examples of polyvinyl ether compounds include homopolymers of vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether, and (2-methoxyethyl) vinyl ether, copolymers of two or more vinyl ethers, copolymers of these vinyl ethers with other monomers, etc. Among these, polyvinyl ether compounds containing methyl vinyl ether as a raw material monomer are preferred from the viewpoint of controlling peeling residues.

[0027] The pellicle adhesive may contain other high molecular weight components in addition to the polyvinyl ether compound. Examples of these high molecular weight components include acrylic polymers (also called acrylic resins), silicone resins, and thermoplastic elastomers. Since acrylic polymers can be selected from a variety of monomer components, they can be easily designed to meet the desired adhesive properties. Silicone resins have an excellent balance of light resistance, adhesive properties, peeling properties, and the like. Thermoplastic elastomers are highly cost-competitive.

[0028] These high molecular weight components are preferably compatible with the polyvinyl ether compound. By increasing the compatibility, it is possible to uniformly disperse the vinyl ether group in the adhesive layer, which is thought to lead to improved peeling properties. When the compatibility is low, it is preferable that the polymer blend state is such that a substantially uniform dispersion can be maintained under the conditions of use of the pellicle adhesive and during the period of use. Here, the polymer blend state means a state in which a thin film (e.g., a thin film of 20 μm) can be formed from the mixture of the polyvinyl ether compound and the high molecular weight component, or a state in which the mixture maintains transparency. In order to maintain these states, a compatibilizer or a solvent that dissolves both the polyvinyl ether compound and the high molecular weight component may be used for mixing.

[0029] The acrylic polymer is, for example, a polymer containing a (meth)acrylic acid ester as a monomer component, and can be copolymerized with a monomer component copolymerizable with the (meth)acrylic acid ester as necessary. Examples of the (meth)acrylic acid ester include a (meth)acrylic acid ester having an ether bond, a (meth)acrylic acid alkyl ester, and an unsaturated monomer having a carboxyl group or a hydroxyl group. By including a (meth)acrylic acid ester having an ether bond as a monomer component, an ether bond can be introduced into the side chain of the acrylic polymer.

[0030] Examples of the (meth)acrylic acid ester having an ether bond (component (A)) include (meth)acrylic acid esters having an alkylene oxide group such as an ethylene oxide group, a propylene oxide group, and a butylene oxide group. Among these, (meth)acrylic acid esters having an ethylene oxide group (also referred to as (meth)acrylates containing an ethylene oxide group) are preferred, and examples thereof include 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, phenoxyethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate such as methoxydiethylene glycol (meth)acrylate, ethoxypolyethylene glycol (meth)acrylate such as ethoxydiethylene glycol (meth)acrylate, butoxypolyethylene glycol (meth)acrylate such as butoxydiethylene glycol (meth)acrylate, and phenoxypolyethylene glycol (meth)acrylate such as phenoxydiethylene glycol (meth)acrylate. These may be used alone or in combination of two or more.

[0031] Examples of (meth)acrylic acid alkyl esters (component (B)) include (meth)acrylic acid alkyl esters having an alkyl group with 1 to 14 carbon atoms. Specific examples include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, and lauryl (meth)acrylate. Among these, (meth)acrylic acid alkyl esters having an alkyl group with 4 or 8 carbon atoms are preferred from the viewpoint of achieving both pressure-sensitive adhesive properties and release properties. These may be used alone or in combination of two or more.

[0032] Examples of unsaturated monomers having a carboxyl group or a hydroxyl group (component (C)) include α,β-unsaturated carboxylic acids such as (meth)acrylic acid, maleic acid, crotonic acid, itaconic acid, and fumaric acid, and hydroxyl group-containing methacrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meth)acrylate. These may be used alone or in combination of two or more.

[0033] In the acrylic polymer, the proportion of the (A) component used in the total monomer components is preferably 30% by mass or more, more preferably 35% by mass or more, particularly preferably 35 to 98% by mass, and extremely preferably 40 to 95% by mass. By setting the proportion of the (A) component within the above range, it becomes easy to control the peeling residue and light resistance.

[0034] In the acrylic polymer, the proportion of the (B) component used is preferably 0 to 70% by mass, more preferably 3 to 55% by mass, based on the total monomer components. By setting the proportion of the (B) component within the above range, it becomes easy to control the adhesion.

[0035] In the acrylic polymer, the proportion of the (C) component used is preferably 0 to 10% by mass, more preferably 2 to 8% by mass, of the total monomer components. By setting the proportion of the (C) component within the above range, it becomes easy to control the degree of crosslinking caused by the reaction with the peeling residue and the curing agent.

[0036] The acrylic polymer can be produced by appropriately selecting a known production method such as solution polymerization, bulk polymerization, emulsion polymerization, radical polymerization, etc. The obtained acrylic polymer may be any of a random copolymer, a block copolymer, a graft copolymer, etc.

[0037] When the molecular weight of the acrylic polymer is within the range of 700,000 to 2,500,000 as the weight average molecular weight, the pressure-sensitive adhesive layer has an appropriate cohesive strength and adhesive strength, is less likely to leave adhesive residue, and has sufficient adhesive strength and load-bearing capacity, which is preferable. The weight average molecular weight is a value measured by gel permeation chromatography (GPC) analysis and is expressed in terms of standard polystyrene. The GPC analysis can be performed using tetrahydrofuran (THF) as a solvent.

[0038] In this embodiment, the adhesive of the adhesive layer preferably contains a reaction product of an acrylic polymer and a curing agent, but may contain an acrylic polymer that does not react with the curing agent in consideration of softness.

[0039] The curing agent is not particularly limited as long as it is a curing material used as a normal adhesive, and examples thereof include metal salts, metal alkoxides, aldehyde compounds, non-amino resin amino compounds, urea compounds, isocyanate compounds, polyfunctional epoxy compounds, metal chelate compounds, melamine compounds, aziridine compounds, etc. Among these, isocyanate compounds and epoxy compounds are preferred from the viewpoint of reactivity with carboxyl groups or hydroxyl groups.

[0040] Examples of the isocyanate compound include xylylene diisocyanate, hexamethylene diisocyanate, tolylene diisocyanate, and multimers, derivatives, polymers, etc. These may be used alone or in combination of two or more.

[0041] Examples of epoxy compounds include compounds having two or more epoxy groups in the molecule, and specific examples thereof include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, diglycidylaniline, diamine glycidylamine, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N'-diamine glycidylaminomethyl), etc. These may be used alone or in combination of two or more.

[0042] As the silicone resin, for example, a silicone resin known as an adhesive can be suitably used. Specifically, an organopolysiloxane having silanol groups at both ends of the molecular chain and RSiO 0.5 (wherein R represents a substituted or unsubstituted monovalent hydrocarbon group) and an organopolysiloxane having a SiO2 unit, and the like. These are available as silicone adhesives KR-101-10, KR-120, KR-130, and X-40-3068 (all of which are product names manufactured by Shin-Etsu Chemical Co., Ltd.).

[0043] Examples of the thermoplastic elastomer include styrene-based thermoplastic elastomers, (meth)acrylic acid ester-based thermoplastic elastomers, olefin-based thermoplastic elastomers, etc. More specifically, the thermoplastic elastomers described in Japanese Patent No. 5513616 can be used. Among these high molecular weight components, acrylic polymers are preferred because it is easy to control the mixability with the polyvinyl ether compound. These high molecular weight components may be used alone or in combination of two or more.

[0044] In the present invention, the content of the polyvinyl ether compound is preferably 0.5 parts by mass or more, more preferably 0.5 to 10 parts by mass, and particularly preferably 3 to 7 parts by mass, per 100 parts by mass of the solid content of the high molecular weight component. By making the content of the polyvinyl ether compound 0.5 parts by mass or more, it becomes easy to suppress the increase in peeling residue caused by ultraviolet irradiation. Also, by making it 10 parts by mass or less, it becomes easy to obtain stable pellicle attachment performance.

[0045] In addition, the adhesive (the composition) that forms the adhesive layer of the pellicle may contain other components such as crosslinkers, tackifiers, plasticizers, stabilizers, viscosity regulators, antistatic agents, lubricants, electrical conductivity agents, flame retardant agents, thermal conductivity improvers, heat resistance improvers, weather resistance improvers, thixotropy agents, antioxidants, antibacterial agents, antifungal agents, and colorants, depending on the purpose, within the scope of the present invention.

[0046] The shape of the adhesive layer 14 is preferably flattened to reduce deformation during pellicle attachment and to suppress residual stress due to pellicle attachment, thereby reducing the effects of distortion and the like on the mask substrate to which it is attached.

[0047] The adhesive layer 14 is formed by applying an uncured liquid or paste adhesive to the lower end surface of the pellicle frame 11, and then performing a curing process to form an adhesive layer. The adhesive may be applied once, or may be applied several times in order to obtain a predetermined thickness of the adhesive layer. In this case, it is preferable to leave the adhesive between each application until the shape of the adhesive after application is stabilized. In addition, if the viscosity of the adhesive is high and application is difficult, the adhesive may be diluted with an organic solvent, alcohol, water, etc. as necessary to reduce the viscosity of the adhesive before application. The adhesive can be applied by, for example, dipping, spraying, brushing, or using an application device such as a dispenser, but application using an application device such as a dispenser is preferable in terms of stability, workability, yield, etc.

[0048] In the manufacture of pellicle 10, normally, the adhesive layer 14 is applied and formed first, and then the pellicle film 12 is stretched, but the order may be reversed. The pellicle film 12 is stretched, for example, by applying an adhesive to the upper end surface of pellicle frame 11, then heating pellicle frame 11 to harden the adhesive, and finally attaching the upper end surface of pellicle frame 11 on which the adhesive layer 13 for attaching the pellicle film has been formed, to a pellicle film mounted on an aluminum frame larger than pellicle frame 11, and removing any excess of the pellicle film that protrudes outside pellicle frame 11 to complete the pellicle.

[0049] By using the pellicle of the present invention having the above-described configuration, it is possible to reduce the amount of adhesive residue when the pellicle is peeled off from the exposure master after use in lithography. In addition, according to the present invention, a method for reducing the peeling residue of the adhesive layer of the pellicle is provided by using the pellicle of the present invention. Therefore, the pellicle of the present invention is useful as a pellicle that can be attached to a phase shift photomask having the above-mentioned delicate phase shift film or a surface mainly composed of silicon oxide such as quartz.

[0050] It is also useful as a pellicle applied to an exposure master in which the pressure-sensitive adhesive layer is irradiated with exposure light during exposure, such as a negative-type exposure master, an exposure master having a non-light-shielded area or a semi-transparent light-shielded area in the adhesive-attached area, an exposure master having a transparent area in the adhesive-attached area, etc. The pressure-sensitive adhesive layer of the pellicle used in such an exposure master is exposed to exposure light through the exposure master from the side opposite to the side of the exposure master on which the pellicle is provided.

[0051] The pellicle of the present invention may be used not only as a protective member for preventing foreign matter from adhering to an exposed master in an exposure device, but also as a protective member for protecting the exposed master during storage or transportation of the exposed master. An exposed master with a pellicle can be manufactured by attaching the above-mentioned pellicle to an exposed master such as a photomask.

[0052] The manufacturing method of a semiconductor device or liquid crystal display panel according to this embodiment includes a step of exposing a substrate (semiconductor wafer or liquid crystal original plate) using the above-mentioned exposure master with pellicle. For example, in a lithography process, which is one of the manufacturing processes of a semiconductor device or liquid crystal display panel, the above-mentioned exposure master with pellicle is placed on a stepper and exposed to light in order to form a photoresist pattern corresponding to an integrated circuit or the like on the substrate. As a result, even if foreign matter adheres to the pellicle in the lithography process, the foreign matter is not imaged on the wafer coated with photoresist, so that short circuits or breaks in the integrated circuits or the like due to the image of the foreign matter can be prevented. Therefore, the use of the exposure master with pellicle can improve the yield in the lithography process.

[0053] In general, when a desired number of lithography steps are performed, when foreign matter or haze occurs, or when the pellicle film is damaged, the pellicle may be peeled off from the exposure master plate and the exposure master plate may be regenerated and cleaned.By using the pellicle of the present invention, even if the exposure master plate has a surface mainly composed of silicon oxide that is likely to cause peeling residue of the adhesive layer, a negative type exposure master plate in which the adhesive layer is irradiated with more exposure light than before, an exposure master plate having a non-shielded area or a semi-transparent light-shielded area in the adhesive attachment part in which the exposure light is irradiated with more exposure light than before, or an exposure master plate having a transparent area in the adhesive attachment part in which the exposure light is irradiated with more exposure light than before, the exposure master plate in which the adhesive layer is irradiated with more exposure light than before, the exposure master plate in which the adhesive layer is irradiated with more exposure light than before, etc., the peeling residue during repellicle can be reduced. In addition, by using the pellicle of the present invention, the amount of peeled off residue of the adhesive layer is reduced, making it easier to apply cleaning with functional water, and the cleaning properties of delicate exposure masters such as phase shift photomasks can be improved. In addition, cleaning with functional water can contribute to reducing the environmental load. EXAMPLES

[0054] The present invention will be specifically illustrated and described below with reference to examples. Note that the "mask" in the examples and comparative examples is described as an example of an "exposure master", and it goes without saying that the present invention can also be applied to a reticle in the same manner.

[0055] Example 1 After precision cleaning of an aluminum alloy pellicle frame (outer dimensions 149mm x 115mm x 3mm, thickness 2mm, flatness of the end surface coated with the adhesive for attaching the mask: 15um), a solution of acrylic adhesive manufactured by Soken Chemical Industries, Ltd. (product name: SK Dyne SN-70A, a solution containing 30% by mass (solid content) of an acrylic polymer in which 95% by mass of the monomer component is ethylene oxide group-containing (meth)acrylate as a base material and 2% by mass (solid content) of a polyvinyl ether compound) was applied to the end surface with a flatness of 15um, and left to stand at room temperature for 60 minutes. After that, a separator was placed on an aluminum plate with a flatness of 5um, and the pellicle frame coated with the adhesive was placed so that the adhesive was facing downwards. As a result, the adhesive came into contact with the flat separator and was flattened. Next, the pellicle on the aluminum plate was placed in a 60°C oven for 60 minutes to harden the adhesive. Then, the pellicle was taken out together with the aluminum plate, and the separator was peeled off.

[0056] Then, an adhesive (product name: Cytop CTX-A) manufactured by Asahi Glass Co., Ltd. was applied to the end surface opposite to the adhesive application. The pellicle frame was then heated at 130°C to harden the adhesive. Finally, the adhesive-coated end face of the pellicle frame was attached to a pellicle film mounted on an aluminum frame larger than the pellicle frame, and the portion outside the pellicle frame was removed to complete the pellicle.

[0057] Next, the 6025 mask substrate and the pellicle prepared above were set in the attachment device, and the pellicle was attached to the mask substrate by applying a pressure of 50 N for a loading time of 30 seconds.

[0058] The mask substrate with the pellicle attached was left at room temperature for 24 hours, and then ultraviolet light was applied from the back of the mask at 10 mJ / cm using a 193 nm ultraviolet lamp so that the light hit the pellicle adhesive. 2 Irradiated. After the ultraviolet irradiation, the mask was left at room temperature for 1 hour, and then the pellicle was slowly peeled upward from the mask substrate at a speed of 0.1 mm / sec.

[0059] Visual inspection of the mask substrate after peeling revealed that the only visible signs were slight faint streaks around the outline of where the pellicle had been attached, and that the mask substrate was clean with almost no peeling residue visible. This residue could be removed in five minutes by immersing it in a cleaning tank (with functional water overflowing) using ultrasonic waves in combination with functional water (ultrapure water to which hydrogen and ammonia have been added).

[0060] Example 2 A pellicle was completed using the same method and materials as in Example 1, except that an adhesive containing 5 parts by mass of a polyvinyl ether compound was used for 100 parts by mass of an acrylic adhesive solution manufactured by Soken Chemical & Engineering Co., Ltd. (product name: SK Dyne SK-1495S, a solution with a solid content of 30% by mass containing an acrylic polymer as a base material that does not contain a (meth)acrylic acid ester having an ether bond as a monomer component). Furthermore, the pellicle was attached to a mask substrate and peeled off under the same conditions as in Example 1.

[0061] When the mask substrate after peeling was visually observed, only a few thin lines were seen around the outline where the pellicle had been attached, and the mask substrate was clean with almost no peeling residue. As in Example 1, this residue could be removed in 5 minutes by immersing it in a cleaning tank (with functional water overflowing) using ultrasonic waves and functional water (ultrapure water with hydrogen and ammonia added).

[0062] Example 3 A pellicle was completed using the same method and materials as in Example 1, except that an adhesive containing 2 parts by mass of a polyvinyl ether compound for 100 parts by mass of an acrylic adhesive solution (product name: SK Dyne SN-70A) manufactured by Soken Chemical & Engineering Co., Ltd. was used as the adhesive. Furthermore, the pellicle was attached to a mask substrate and peeled off under the same conditions as in Example 1.

[0063] When the mask substrate after peeling was visually observed, only a few thin lines were seen around the outline where the pellicle had been attached, and the mask substrate was clean with almost no peeling residue. As in Examples 1 and 2, this residue could be removed in 3 minutes by immersing it in a cleaning tank (with functional water overflowing) using ultrasonic waves and functional water (ultrapure water with hydrogen and ammonia added).

[0064] Example 4 A pellicle was completed using the same method and materials as in Example 1, except that an adhesive containing 11 parts by mass of a polyvinyl ether compound for 100 parts by mass of an acrylic adhesive solution (product name: SK Dyne SK-1495S) manufactured by Soken Chemical & Engineering Co., Ltd. was used as the adhesive. Furthermore, the pellicle was attached to a mask substrate and peeled off under the same conditions as in Example 1.

[0065] When the mask substrate after peeling was visually observed, only a few thin lines were seen around the outline where the pellicle had been attached, and the mask substrate was clean with almost no peeling residue. This residue could be removed in 3 minutes by immersing it in a cleaning tank (with functional water overflow) using ultrasonic waves and functional water (ultrapure water with hydrogen and ammonia added) in the same manner as in Example 1-3.

[0066] Example 5 A pellicle was completed using the same method and materials as in Example 1, except that an adhesive containing 3 parts by mass of a polyvinyl ether compound was used for 100 parts by mass of an acrylic adhesive solution manufactured by Soken Chemical & Engineering Co., Ltd. (product name: SK Dyne SK-1425S, a solution with a solid content of 30% by mass containing an acrylic polymer as a base material that does not contain a (meth)acrylic acid ester having an ether bond as a monomer component). Furthermore, the pellicle was attached to a mask substrate and peeled off under the same conditions as in Example 1. When the mask substrate was visually inspected after peeling, a thin adhesive residue was found in the area where the pellicle had been attached. This residue was also removed by ultrasonic cleaning with functional water for 5 minutes x 5 times.

[0067] Comparative Example 1 A pellicle was completed using the same method and materials as in Example 1, except that a polyvinyl ether compound was not used as the adhesive, and only an acrylic adhesive solution (product name: SK Dyne SK-1495S) manufactured by Soken Chemical & Engineering Co., Ltd. was used. Furthermore, the pellicle was attached to a mask substrate and peeled off under the same conditions as in Example 1.

[0068] When the mask substrate was visually inspected after peeling, a thin adhesive residue was found in the area where the pellicle had been attached. The peeling residue was removed by washing twice for 5 minutes using the same equipment as in Example 1, but it could not be completely removed, so it was necessary to lightly rub the surface with a polyvinyl alcohol foam before the washing.

[0069] Comparative Example 2 A pellicle was completed using the same method and materials as in Example 1, except that a polyvinyl ether compound was not used as the adhesive, and only an acrylic adhesive solution (product name: SK Dyne SK-1425S) manufactured by Soken Chemical & Engineering Co., Ltd. was used. Furthermore, the pellicle was attached to a mask substrate and peeled off under the same conditions as in Example 1.

[0070] When the mask substrate was visually inspected after peeling, a thin adhesive residue was found in the area where the pellicle had been attached. The peeling residue was removed by washing twice for 5 minutes using the same equipment as in Example 1, but it could not be completely removed, so it was necessary to lightly rub the surface with a polyvinyl alcohol foam before the washing. From the results of the examples, it was confirmed that by using an acrylic polymer containing polyvinyl ether as an adhesive, it is possible to peel off the film satisfactorily with almost no peeling residue remaining on the exposed substrate, even when the film is irradiated with 193 nm ultraviolet light after being attached to the exposed substrate. [Explanation of symbols]

[0071] 1 Exposure master 10 Pellicle 11 Pellicle frame 12 Pellicle membrane 13 Adhesive layer for attaching pellicle membrane 14 Adhesive layer 15 Air pressure adjustment hole (vent) 16 Dust removal filter

Claims

1. A pellicle frame with an adhesive layer, comprising: a pellicle frame; an adhesive layer obtained from an adhesive for a pellicle for attaching a pellicle to an exposure master plate provided on one end surface of the pellicle frame; and a liner for protecting the adhesive layer, the liner is releasably provided on the pressure-sensitive adhesive layer, The pellicle adhesive is a pellicle frame with an adhesive layer, which comprises a polyvinyl ether compound and at least one member selected from the group consisting of an acrylic polymer, a silicone resin, and a thermoplastic elastomer.

2. A pellicle frame with an adhesive layer, comprising: a pellicle frame; an adhesive layer obtained from an adhesive for a pellicle for attaching a pellicle to an exposure master plate provided on one end surface of the pellicle frame; and a liner for protecting the adhesive layer, the liner is releasably provided on the pressure-sensitive adhesive layer, The pellicle adhesive comprises a polyvinyl ether compound and an acrylic polymer, and the content of the polyvinyl ether compound is 0.5 to 10 parts by mass per 100 parts by mass of the solid content of the acrylic polymer.

3. A pellicle frame with an adhesive layer as described in claim 1 or 2, wherein the polyvinyl ether compound is a polymer having vinyl ethers as monomer components, or a polymer having vinyl ethers and monomers copolymerizable with vinyl ethers as polymerization components.

4. 4. The pellicle frame with an adhesive layer according to claim 3, wherein the vinyl ether is at least one selected from the group consisting of methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether and (2-methoxyethyl) vinyl ether.

5. 5. The pellicle frame with an adhesive layer according to claim 1, wherein the acrylic polymer contains a (meth)acrylic acid ester having an ether bond as a monomer component.

6. 6. The pellicle frame with an adhesive layer according to claim 5, wherein the (meth)acrylic acid ester having an ether bond is a (meth)acrylic acid ester having an ethylene oxide group.

7. A pellicle comprising a pellicle membrane and a pellicle frame with an adhesive layer according to any one of claims 1 to 6.

8. 8. An exposure master with a pellicle, comprising the pellicle according to claim 7 attached to the exposure master.

9. 9. An exposure method comprising exposing using the exposure master with a pellicle according to claim 8.

10. A method for manufacturing a semiconductor device, comprising a step of exposing using the exposure master with a pellicle according to claim 8.

11. A method for manufacturing a liquid crystal display panel, comprising a step of exposing using the exposure master with a pellicle according to claim 8.

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