JP7421976B2 - Pellicle and its manufacturing method - Google Patents

Description

The present invention relates to a pellicle used as a dust guard for a lithography mask in a lithography process for semiconductor devices such as LSIs and VLSIs, liquid crystal display panels, etc., and a method for manufacturing the same.

A pellicle is used in a lithography process for semiconductor devices such as LSIs and VLSIs, liquid crystal display panels, etc., by being attached to a lithography mask to prevent foreign matter from adhering to the mask. A pellicle usually has a pellicle frame, a transparent pellicle membrane stretched over its upper end surface, and an adhesive layer provided on its lower end surface for attaching the pellicle to a mask. Adhesives used in the adhesive layer of the pellicle include rubber-based or polyurethane-based adhesives, silicone-based adhesives as described in Patent Document 1, and acrylic-based adhesives as described in Patent Document 2. It has been known.

In recent years, with the miniaturization of mask patterns, the wavelength of exposure light has become shorter. Examples of short wavelength light include excimer light such as KrF excimer laser and ArF excimer laser. Since such short wavelengths have high energy, the adhesive component is likely to decompose during exposure, and the decomposition of the adhesive component may cause problems such as peeling off of the pellicle from the mask during the exposure process. In order to prevent such problems, the adhesive layer of the pellicle is required to have a load-bearing property that will not peel off even when a certain load is applied.

For example, Patent Document 2 discloses a pellicle in which the adhesive layer has a cohesive breaking strength of 20 g/mm ² or more.

Japanese Patent Application Publication No. 05-281711 Japanese Patent Application Publication No. 2006-146085

In Patent Document 2, the cohesive rupture strength of the adhesive layer is increased as a method for improving adhesive residue after pellicle peeling. However, when the cohesive breaking strength is increased, the adhesive layer tends to become harder, and as a result, the load-bearing property often decreases.

An object of the present invention is to provide a pellicle that has high adhesion to a substrate and excellent load resistance, and a method for manufacturing the same.

The present invention is a cured product of a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B), as a result of intensive research aimed at solving such problems. ) By irradiating the pellicle, which has an adhesive layer containing an acrylic adhesive, with ultraviolet rays of a specific wavelength, the hardness of the outermost surface of the adhesive layer increases, and at the same time, the adhesive strength improves, resulting in better adhesion to the substrate. was found to increase. In particular, the stress generated when the indentation depth is 4 μm is 25 μN or more and 50 μN or less, as measured by the nanoindentation method on the surface of the adhesive layer of the pellicle opposite to the surface in contact with the pellicle frame after UV irradiation. It has been found that within this range, the load resistance is improved. Although the reason is not certain, it is presumed as follows.

The adhesive layer of the pellicle of the present invention contains a (meth)acrylic adhesive that is a cured product of a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B). It will be done. When UV rays of a specific wavelength are irradiated so that the stress on the outermost surface of the adhesive layer (i.e., the indentation depth of 4 μm) is within the above range, the (meth)acrylic adhesive contained in the surface of the adhesive layer is It is thought that the amount of -OH and -COOH, which are functional groups that can improve the adhesiveness of the adhesive, increased, and the adhesion between the substrate and the adhesive layer improved. Based on these findings, we have completed the present invention.

Therefore, the present invention relates to the following pellicle.
[1] A pellicle frame,
a pellicle membrane stretched over one end surface of the pellicle frame;
A pellicle comprising an adhesive layer provided on the other end surface of the pellicle frame,
The adhesive layer includes a (meth)acrylic adhesive that is a cured product of a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B),
The stress measured on the surface of the adhesive layer opposite to the surface in contact with the pellicle frame is 25 μN or more and 50 μN or less, and the stress is measured by a nanoindentation method when the indentation depth is 4 μm. A pellicle is a stress that sometimes occurs.
[2] The (meth)acrylic acid ester copolymer (A) has a structural unit derived from a (meth)acrylic acid ester and a side chain consisting of a carbon-carbon multiple bond-containing group, as described in [1]. pellicle.
[3] The pellicle according to [2], wherein the carbon-carbon multiple bond-containing group is a carbon-carbon double bond-containing group.
[4] The pellicle according to any one of [1] to [3], wherein the curing agent (B) is a radical polymerization initiator.
[5] The pellicle according to [4], wherein the radical polymerization initiator is a thermal radical polymerization initiator.

Furthermore, the present invention relates to the following method for manufacturing a pellicle.
[6] A method for manufacturing a pellicle according to any one of [1] to [5], comprising:
a step of stretching a pellicle membrane on one end surface of the pellicle frame;
providing an adhesive layer on the other end surface of the pellicle frame using a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B);
irradiating the composite including the pellicle film, the pellicle frame, and the adhesive layer with ultraviolet rays having a wavelength of 193 nm or less in an oxygen gas atmosphere,
By the step of irradiating the ultraviolet rays, the stress measured on the surface of the adhesive layer opposite to the surface in contact with the pellicle frame becomes 25 μN or more and 50 μN or less, and the stress is measured by a nanoindentation method. , is the stress that occurs when the indentation depth is 4 μm,
How to make a pellicle.
[7] The (meth)acrylic ester copolymer (A) has a structural unit derived from a (meth)acrylic ester and a side chain consisting of a carbon-carbon multiple bond-containing group, as described in [6]. manufacturing method.

According to the present invention, it is possible to provide a pellicle that has high adhesion to a substrate and excellent load resistance, and a method for manufacturing the same.

FIG. 1 is a schematic diagram showing the configuration of a load-bearing test.

1. Pellicle The pellicle of the present invention includes a pellicle frame, a pellicle membrane stretched over one end surface of the pellicle frame, and an adhesive layer provided on the other end surface of the pellicle frame.

1-1. Pellicle Frame The pellicle frame may be one commonly used as a pellicle frame. Examples of materials for the pellicle frame include aluminum alloy, stainless steel, polyethylene, black alumite-treated aluminum, and the like. Among these, aluminum alloys, black alumite-treated aluminum, and the like are preferred because of their light weight.

1-2. Pellicle Membrane The pellicle membrane is fixed to one opening of the pellicle frame. The pellicle membrane may be one commonly used as a pellicle membrane. Examples of the material for the pellicle membrane include nitrocellulose, ethylcellulose, cellulose acetate, cellulose propionate, pullulan compounds, amorphous fluoropolymers, and silicone-modified polyvinyl alcohol. Among these, amorphous fluoropolymers having sufficient resistance to excimer light are preferred.

1-3. Adhesive Layer The adhesive layer contains a (meth)acrylic adhesive that is a cured product of a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B).

[(meth)acrylic acid ester copolymer (A)]
In the present invention, "(meth)acrylic acid ester copolymer (A) (hereinafter sometimes abbreviated as "copolymer (A)") is a (meth)acrylic acid ester copolymer (meth) having an alkyl group having 1 to 14 carbon atoms. It is preferable that the monomer unit contains an acrylic acid alkyl ester and a reactive monomer having a functional group that is reactive with the curing agent (B) described below.

Specific examples of (meth)acrylic acid alkyl esters in which the alkyl group has 1 to 14 carbon atoms include butyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, and decyl (meth)acrylate. , (meth)acrylic esters of linear aliphatic alcohols such as dodecyl (meth)acrylate, lauryl (meth)acrylate, isobutyl (meth)acrylate, isoamyl (meth)acrylate, and 2-(meth)acrylate. Examples include ethylhexyl, isooctyl (meth)acrylate, isononyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, and the like. These may be used alone or in combination of two or more. Among them, two types of combinations of (meth)acrylic acid alkyl ester having an alkyl group having 1 to 3 carbon atoms and a (meth)acrylic acid alkyl ester having an alkyl group having 4 to 14 carbon atoms are used. is preferred. For example, a combination of butyl (meth)acrylate, octyl (meth)acrylate, etc., and methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, etc. be.

Examples of reactive monomers having a functional group reactive with a curing agent include carboxyl group-containing monomers such as (meth)acrylic acid, itaconic acid, maleic acid, and crotonic acid, 2-hydroxyethyl (meth)acrylate, Examples include hydroxyl group-containing monomers such as 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. These monomers may be used alone or in combination of two or more. Among them, from the viewpoint of copolymerizability, versatility, etc., hydroxyl group-containing compounds having a hydroxyalkyl group having 2 to 4 carbon atoms, such as 2-hydroxyethyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate, are preferred. Carboxyl group-containing monomers such as meth)acrylate and (meth)acrylic acid are preferred. Particularly from the viewpoint of reducing adhesive residue, (meth)acrylic acid is preferred.

Furthermore, the copolymer (A) is a polymer having a structural unit derived from (meth)acrylic acid ester (hereinafter also referred to as "structural unit (I)") and a side chain consisting of a carbon-carbon multiple bond-containing group. It is preferable that there be. Moreover, it is preferable that the copolymer (A) further has a structural unit containing a hydroxy group (hereinafter also referred to as "structural unit (II)") in addition to the structural unit (I). Furthermore, it may further contain structural units other than structural units (I) to (II).

The copolymer (A) further has a side chain consisting of a carbon-carbon multiple bond-containing group. The carbon-carbon multiple bond-containing group may be included in structural unit (II) or other structural units. The carbon-carbon multiple bond-containing group and each structural unit will be explained below.

(Carbon-carbon multiple bond-containing group)
The carbon-carbon multiple bond-containing group is not particularly limited as long as it contains a carbon-carbon double bond and/or a carbon-carbon triple bond. Polymerizable carbon-carbon multiple bonds refer to ethylenic as well as alkyne carbon-carbon multiple bonds.

The carbon-carbon double bond-containing group is not particularly limited as long as it is a group containing a carbon-carbon double bond. Examples include polyethylene glycol #600 diacrylate, isoprene, diallyl ether, divinylbenzene ((meth)acryloyl group, vinyl group, allyl group, styryl group, etc.). Further, the carbon-carbon triple bond-containing group is not particularly limited as long as it is a group containing a carbon-carbon triple bond. Examples include hexane-1,5-diyne, diethynylbenzene, and diethylene glycol bis(2-propynyl) ether. Among these, a (meth)acrylic group, which is a carbon-carbon double bond-containing group, is preferred from the viewpoint of being superior in radical stability and reactivity and sufficiently increasing the extent of decrease in adhesive strength after heating.

In this specification, when the expression "(meth)acrylic" is used, it means one or both of "acrylic" and "methacrylic", and "(meth)acryloyl" has the same meaning. shall be.

The copolymer (A) may have a multiple bond-containing group either in the side chain or at the end, but it improves the reactivity of the polymerizable carbon-carbon multiple bond and reduces the adhesiveness after heating or UV curing. From the viewpoint of sufficiently increasing the range of decrease in force, it is preferable to have it in the side chain.

The copolymer (A) in which multiple bond-containing groups have been introduced into the side chains can be obtained by preparing a precursor polymer having hydroxy groups or epoxy groups in the side chains, and adding multiple bonds to the hydroxy groups or carboxy groups of the precursor polymer. It can be obtained by a method of reacting an isocyanate compound and an epoxy compound having a bond.

The range of multiple bond equivalent, which represents the content of multiple bond-containing groups in the copolymer (A), is preferably from 156 g/mol to 100,000 g/mol, more preferably from 500 g/mol to 50,000 g/mol. It is preferably 1000 g/mol or more and 20,000 g/mol or less. By setting the content of the multiple bond-containing group within the above range, the adhesive strength after curing by heating or UV irradiation can be designed from weak to strong adhesive, and adhesive residue can be more sufficiently reduced.

The multiple bond equivalent is the solid content mass (g) of the copolymer (A) with respect to the total number of moles (mol) of multiple bonds (i.e., double bonds and triple bonds) possessed by the copolymer (A), It can be expressed by the following formula.
Multiple bond equivalent (g/mol)=solid mass (g) in copolymer (A)/number of moles of multiple bonds in copolymer (A).
In addition, the solid content mass of copolymer (A) here is the average molecular weight (Mw) of copolymer (A). Moreover, the number of moles of multiple bonds in the copolymer (A) is the number of moles of the compound having a polymerizable multiple bond group located in the side chain.

The weight average molecular weight (Mw) of the copolymer (A) is the weight average molecular weight in terms of polystyrene determined by GPC. The measuring method will be described later.

Further, the number of moles of multiple bonds in the copolymer (A) can be calculated from the integral value of ¹ H-NMR. For example, prepare a solution in which an arbitrary amount (for example, 0.1 mmol) of a standard reagent (such as styrene) is added to the copolymer (A), dilute it with a heavy solvent (for example, CDCl ₃ ), Prepare sample solution. A spectrum is obtained by measuring ¹ H-NMR of the prepared sample solution. Regarding the obtained spectrum, the number of moles of multiple bonds can be obtained from the integral value of the peak derived from the standard reagent and the integral value of the peak derived from the multiple bond contained in the copolymer (A).

(Structural unit (I))
Structural unit (I) is a structural unit derived from (meth)acrylic acid ester. Structural unit (I) has a structure represented by -CH ₂ -CH(COOCH ₃ )-.

Further, the structural unit (I) is a structural unit derived from a (meth)acrylic acid alkyl ester containing an alkyl group having 4 or more and 10 or less carbon atoms. Examples of the alkyl group having 4 to 10 carbon atoms include n-butyl group, n-pentyl group, n-hexyl group, n-octyl group, 2-ethylhexyl group, n-decyl group, and the like. Among these, n-butyl group and 2-ethylhexyl group are preferred.

Further, the structural unit (I) is preferably one in which the eliminated product derived from the structural unit (I) becomes a compound having a boiling point of 150° C. or lower. For example, when the structural unit (I) is butyl acrylate, the eliminated product is butanol with a boiling point of 117°C. If the boiling point of the desorbed product is 150° C. or lower, outgas can be easily removed. Structural units (I) that produce desorbed products with a boiling point of 150°C or less include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, vinyl acetate, etc. Examples include (meth)acrylic acid esters in which the number of carbon atoms in the ester group is 5 or less.

When the copolymer (A) has a structural unit (I), the lower limit of the content of the structural unit (I) is preferably 5% by mass, more preferably 10% by mass, even more preferably 30% by mass, and 40% by mass. % by weight is particularly preferred. The upper limit of the content ratio is preferably 95% by mass, more preferably 80% by mass, even more preferably 70% by mass, and particularly preferably 60% by mass. By setting the content of the structural unit (I) within the above range, the strength of the adhesive layer can be further increased, and as a result, the adhesive force can be further increased. By setting the content ratio of the structural unit (I) within the above range, the adhesive strength can be designed from weak to strong, and adhesive residue can be sufficiently reduced.

(Structural unit (II))
Structural unit (II) is a structural unit containing a hydroxy group. When the copolymer (A) has the structural unit (II), the adhesive strength is further improved.

Examples of the hydroxy group include alcoholic hydroxy groups. Among these, alcoholic hydroxy groups are preferred from the viewpoint of reducing adhesive residue.

Examples of monomers providing structural unit (II) include hydroxyalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate; hydroxyphenyl (meth)acrylate, hydroxynaphthyl Examples include hydroxyaryl (meth)acrylates such as (meth)acrylates. Among these, hydroxyalkyl (meth)acrylate is preferred, hydroxyalkyl acrylate is more preferred, and hydroxyethyl acrylate is even more preferred.

When the copolymer (A) has a structural unit (II), the lower limit of the content of the structural unit (II) is preferably 1% by mass, more preferably 3% by mass, even more preferably 4% by mass, and 5% by mass. % by weight is particularly preferred. The upper limit of the content ratio is preferably 30% by mass, more preferably 25% by mass, even more preferably 15% by mass, and particularly preferably 10% by mass.

The weight average molecular weight of the copolymer (A) is preferably from 10,000 to 1,000,000, and more preferably from 30,000 to 100,000. If it is within the above range, the cohesive force and adhesive force of the pressure-sensitive adhesive layer will be appropriate, and adhesive will not easily remain, which is preferable.

Note that the weight average molecular weight is a polystyrene equivalent weight average molecular weight (Mw) determined by gel permeation chromatography (GPC).

The lower limit of the molecular weight distribution of the copolymer (A), that is, the ratio of Mw to the polystyrene equivalent number average molecular weight (Mn) by GPC (Mw/Mn) is usually 1, preferably 1.1. The upper limit of the above ratio is preferably 5, more preferably 3, even more preferably 2, and particularly preferably 1.7. When the molecular weight distribution is within the above range, the degree of crosslinking can be controlled, and functional groups that are considered to be bad for adhesive residue can be better controlled, thereby reducing adhesive residue.

In this specification, the GPC conditions used to measure Mw and Mn of copolymer (A) are as follows.
GPC columns: For example, two Tosoh “TSKgel Multipore HXL-M” Column temperature: 40°C
Elution solvent: Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.)
Flow rate: 1.0mL/min Sample concentration: 0.05% by mass
Sample injection volume: 100μL
Detector: Differential refractometer Standard material: Monodisperse polystyrene

[Curing agent (B)]
The type of curing agent (B) used in the adhesive is not particularly limited as long as it can polymerize the copolymer (A) used, but a radical polymerization initiator is preferable. Further, as the radical polymerization initiator, a photo radical polymerization initiator and a thermal radical polymerization initiator can be used.

The photoradical polymerization initiator refers to a compound that generates radicals when irradiated with light, that is, a compound that absorbs light energy and decomposes to generate radical species. Further, the thermal radical polymerization initiator refers to a compound that generates radicals by heat, that is, a compound that absorbs thermal energy and decomposes to generate radical species. When using a radical polymerization initiator as the curing agent (B), either one of a photo radical polymerization initiator and a thermal radical polymerization initiator can be used, or multiple types of radical polymerization initiators can be used in combination. You can also do it. Pellicles are used under light irradiation, so in order to prevent the photo-radical polymerization initiator remaining in the adhesive from reacting with the light in the usage environment and changing the physical properties and characteristics of the adhesive, it is necessary to A thermal radical polymerization initiator is preferable to a radical polymerization initiator. In addition, since the resin composition is applied to the pellicle frame to form an adhesive layer, it is necessary to use a thermal radical polymerization initiator and a photoradical polymerization initiator together in order to easily increase the thickness of the adhesive layer. You can also do it.

As the thermal radical polymerization initiator, a peroxide radical polymerization initiator or an azo radical polymerization initiator is preferable.

Specific examples of peroxide-based radical polymerization initiators include the following compounds and commercially available products. Diisobutyryl peroxide, cumyl peroxyneodecanoate, di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, di-sec-butyl peroxydicarbonate, 1,1,3,3-tetramethylbutyl Peroxyneodecanoate, di(4-t-butylcyclohexyl)peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, t-hexylperoxyneodecanoate, t-butylperoxyneodecano ate, t-butyl peroxy neoheptanoate, t-hexyl peroxy pivalate, t-butyl peroxy pivalate, di(3,5,5-trimethylhexanoyl) peroxide, dilauroyl peroxide, 1, 1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, disuccinic acid peroxide, 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, t-hexylperoxide Oxy-2-ethylhexanoate, di(4-methylbenzoyl)peroxide, t-butylperoxy-2-ethylhexanoate, di(3-methylbenzoyl)peroxide, benzoyl(3-methylbenzoyl)peroxide oxide, dibenzoyl peroxide, dibenzoyl peroxide, 1,1-di(t-butylperoxy)-2-methylcyclohexane, 1,1-di(t-hexylperoxy)-3,3,5-trimethyl Cyclohexane, 1,1-di(t-hexylperoxy)cyclohexane, 1,1-di(t-butylperoxy)cyclohexane, 2,2-di[4,4-di(t-butylperoxy)cyclohexyl] ] Propane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, t-butylperoxy Isopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-butylperoxyacetate, 2, 2-di(t-butylperoxy)butane, t-butylperoxybenzoate, n-butyl-4,4-di-t-butylperoxyvalerate, di(2-t-butylperoxyisopropyl)benzene, dichloromethane Mil peroxide, di-t-hexyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-butyl peroxide, p-methane Hydroperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexan-3-yne, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene Hydroperoxide, t-butylhydroperoxide, 2,4-dichlorobenzoyl peroxide, o-chlorobenzoyl peroxide, p-chlorobenzoyl peroxide, tris(t-butylperoxy)triazine, 2,4,4- Trimethylpentylperoxyneodecanoate, α-cumylperoxyneodecanoate, t-amylperoxy 2-ethylhexanoate, t-butylperoxyisobutyrate, di-t-butylperoxyhexahydroterephthalate , di-t-butylperoxytrimethyladipate, di-3-methoxybutylperoxydicarbonate, diisopropylperoxydicarbonate, t-butylperoxyisopropyl carbonate, 1,6-bis(t-butylperoxycarbonyloxy) Examples include hexane, diethylene glycol bis(t-butyl peroxycarbonate), and t-hexyl peroxyneodecanoate.

Ketone peroxides such as Perhexa H commercially available from NOF Corporation, peroxyketals such as Perhexa TMH, hydroperoxides such as Perbutyl H-69, Percyl D, Perbutyl C, Perbutyl D, Perbutyl O, etc. Diacyl peroxides such as Niper BW, peroxyesters such as Perbutyl Z and Perbutyl L, and peroxydicarbonates such as Perloyl TCP.

In addition, Kayaku Akzo's Trigonox 36-C75, Laurox, Perkadox L-W75, Perkadox CH-50L, Trigonox TMBH, Kayakumen H, Kayabutyl H-70, Perkadox BC-FF, Kayahexa AD, Perkadox 14 , Kayabutyl C, Kayabutyl D, Perkadox 12-XL25, Trigonox 22-N70 (22-70E), Trigonox D-T50, Trigonox 423-C70, Kaya Ester CND-C70, Trigonox 23-C70, Trigonox 257-C70, Kaya Ester P-70, Kaya Ester TMPO-70, Trigonox 121, Kaya Ester O, Kaya Ester HTP-65W, Kaya Ester AN, Trigonox 42, Trigonox F-C50, Kayabutyl B, Kayacarvone EH, Kayacarvone I-20, Kayacarvone BIC- 75, Trigonox 117, and Kayalen 6-70.

The above peroxide-based radical polymerization initiators may be used alone or in combination.

Examples of the azo radical polymerization initiator include compounds having an azo group, such as azonitrile compounds, azo ester compounds, azoamide compounds, azoamidine compounds, azoimidazoline compounds, and polymeric azo compounds.

Examples of polymeric azo compounds include trade names VPE-0201, VPE-0401, VPE-0601, and VPS-1001 (all manufactured by Wako Pure Chemical Industries, Ltd.).

The above azo radical polymerization initiators may be used alone or in combination.

The 10-hour half-life temperature of the radical polymerization initiator is preferably 50°C to 150°C, more preferably 60°C to 140°C, even more preferably 70°C to 130°C. When the 10-hour half-life temperature is within the above range, there are few curing defects, so it is possible to suppress adhesive residue.

Note that the numerical value of the 10-hour half-life temperature of the radical polymerization initiator can also be obtained from literature, and the catalog of the manufacturer can be referred to. For example, the catalog values of NOF Corporation (http://www.nof.co.jp/upload_public/sogo/B0100.pdf) can be referred to.

The photoradical polymerization initiator used as the curing agent (B) in the present invention is not particularly limited as long as it has absorption in the light source used during photocuring. Further, as the photoradical polymerization initiator, a UV irradiation curing agent is preferable.

Specific examples of photoradical polymerization initiators include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 1-[4-(2-hydroxyethoxy) )-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl- 2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2-hydroxy-1-{4-[4-(2 -Hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propane, 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyloxime)], 2- Hydroxy-2-methyl-1-phenyl-propan-1-one, phenylglyoxylic acid methyl ester, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, and the like can be used.

The above compounds are available as commercial products, and include OMNIRAD1000, 248, 481, 4817, 4MBZ-flakes, 500, 659, 73, 784, 81, BDK, MBS, and 4MBZ-flakes. BP-flakes, DETX, EDB, EHA, EMK, ITX, MBF, OMBB, TPO, 410, BL723, BL724, BL750, BL751, 1173, 127, 184, 184FF, 2022, 2100, 2959, 369, 369E, 379, 379EG, 4265, 754, 819, 819DW, 907, 907FF, BP, 127D, ESACURE1001M, ONE, A198, KIP 160, KIP 150, KIP100F, KIP-LT, KIP-IT, KTO-46, DP-250, TZT, KT-55 (manufactured by IMG) ), etc.

The amount of the curing agent (B) in the resin composition is preferably 0.01 to 10 parts by mass, and preferably 0.05 to 5 parts by mass, based on 100 parts by mass of the copolymer (A). is more preferable. If the amount of the curing agent (B) is 0.01 parts by mass or more, the curability is sufficient, and if the amount is 10 parts by mass or less, there is no fear that a large amount of outgas derived from the curing agent (B) will be generated. .

[Crosslinking agent (C)]
The resin composition according to the present invention may further contain a crosslinking agent (C).
The crosslinking agent (C) is a component that can form a crosslinked structure in the copolymer (A) by heating. When the resin composition further contains a crosslinking agent (C), a pressure-sensitive adhesive layer having a crosslinked structure can be formed.

The crosslinking agent (C) is preferably a polyfunctional compound having carbon-carbon multiple bonds, and particularly preferably polyfunctional (meth)acrylate.

The polyfunctional (meth)acrylate is not particularly limited as long as it has 2 to 10 (meth)acryloyl groups, but it is preferable that the number of (meth)acryloyl groups is 2 to 6.

Specific examples of the polyfunctional (meth)acrylate used as the crosslinking agent (C) include the following compounds. Alkyl (meth)acrylate, hydroxyl group-containing alkyl acrylate, polyalkylene glycol acrylate, dioxane acrylate, tricyclodecanol acrylate, fluorene acrylate, alkoxylated bisphenol A acrylate, (alkoxylated) trimethylolpropane acrylate, alkoxylated serine acrylate, ( caprolactone-modified) isocyanurate acrylate, pentaerythritol acrylate, alkoxylated pentaerythritol acrylate, (alkoxylated) pentaerythritol acrylate, (alkoxylated) ditrimethylolpropane acrylate, (alkoxylated) dipentaerythritol acrylate.

Preferred examples of polyfunctional acrylate compounds include polyethylene glycol #400 diacrylate (NK Ester A-400 (molecular weight 508)), polyethylene glycol #600 diacrylate (NK Ester A-600 (molecular weight 742), manufactured by Shin Nakamura Chemical Co., Ltd. )), A-DOD-N, A-BPE-10, A-GLY-9E, A-9300, A-9300-1CL, and AD-TMP-L.

The crosslinking agent (C) is more preferably a bifunctional or higher (meth)acrylate curing agent containing 2 to 10 acrylate groups in one molecule. Specific examples of such compounds include glycerolpropyl tri(meth)acrylate, ditrimethyloltetra(meth)acrylate, and dipentaerythritol penta(meth)acrylate.

There is no particular limitation on the content of carbon-carbon multiple bonds possessed by the crosslinking agent (C), but the multiple bond equivalent is preferably 60 g/mol or more and 1000 g/mol or less, more preferably 80 g/mol or more and 900 g/mol or less. , more preferably 100 g/mol or more and 700 g/mol or less, further preferably 200 g/mol or more and 400 g/mol or more.
Incidentally, the multiple bond equivalent can be determined by the method described above in connection with the copolymer (A).

The blending amount of the crosslinking agent (C) is preferably 0 parts by mass or more and 20 parts by mass or less, and more preferably 0.5 parts by mass or more and 5 parts by mass or less, based on 100 parts by mass of the copolymer (A). By setting the content of the crosslinking agent (C) within the above range, adhesive residue can be further suppressed.

[Other ingredients]
The resin composition according to the present invention may contain other optional components in addition to the above components. Examples of optional components include antioxidants, anti-aging agents, ultraviolet absorbers, light stabilizers, antifoaming agents, leveling agents, antistatic agents, surfactants, storage stabilizers, thermal polymerization inhibitors, plasticizers, Examples include wettability improvers, adhesion agents, tackifiers (Tacky Fire), organic solvents, and the like. These optional components may be used alone or in combination of two or more.

Such optional components may be added in an amount that does not impair the effects of the present invention. For example, the amount may be 0 parts by mass or more and 10 parts by mass or less based on 100 parts by mass of the entire resin composition. It is.

[(meth)acrylic adhesive]
There are no particular limitations on the method for producing the (meth)acrylic adhesive that forms the adhesive layer of the pellicle, and any known method for producing an adhesive may be used. For example, (meth)acrylic-based A (meth)acrylic adhesive can be obtained by obtaining a resin composition and curing a solution of the adhesive.

A (meth)acrylic pressure-sensitive adhesive can be obtained by curing the resin composition according to the present invention, but for the curing method and the like, please refer to step 2) of the pellicle manufacturing method below.

[Characteristics of adhesive layer]
The pressure-sensitive adhesive layer in the pellicle of the present invention has a stress of 25 μN or more and 50 μN or less when measured on the surface opposite to the surface in contact with the pellicle frame. The stress is the stress that occurs when the indentation depth is 4 μm, as measured by the nanoindentation method.

If the above-mentioned stress is within the range of 25 μN or more and 50 μN or less, the adhesive layer will not peel off from the mask substrate when a load is applied to the exposure master plate including the mask substrate and the pellicle attached via the adhesive layer. It becomes possible to suppress the In particular, if the stress is 25 μN or more, the load resistance will increase, and if the stress is 50 μN or less, the curing of the resin composition will not progress too much and the adhesion will not deteriorate. The stress range is preferably 34 μN or more and 42 μN or less, more preferably 39 μN or more and 40 μN or less.

In the present invention, the stress of the adhesive layer is a value measured in accordance with ISO 14577-1 (instrumented indentation hardness). For example, in the examples of the present application, a nanoindentation method was carried out using Hyditron TI Premier (manufactured by Bruker) as an apparatus. Specifically, a 20 μm conical diamond indenter was brought into contact with the adhesive layer, and the indenter was pushed in from there to a depth of 4 μm at a pushing speed of 0.8 μm/sec, and the stress generated at this time was measured.

2. Method for manufacturing a pellicle The pellicle of the present invention can be manufactured by a method including the following steps.
Step 1) of stretching a pellicle membrane on one end surface of the pellicle frame;
Step 2) of providing an adhesive layer on the other end surface of the pellicle frame using a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B);
Step 3) of irradiating the composite including the pellicle film, the pellicle frame, and the adhesive layer with ultraviolet light having a wavelength of 193 nm or less in an inert gas atmosphere.

The pellicle of the present invention is different from the conventional pellicle except that in step 2), an adhesive layer is provided using the above-mentioned (meth)acrylic resin composition, and in step 3), ultraviolet irradiation is performed. It can be manufactured similarly. Note that step 1) and step 2) can also be performed with the order changed.

Regarding step 1), a pellicle membrane is stretched over one opening of the pellicle frame. The pellicle membrane can be stretched in a conventional manner. For example, a commonly used adhesive may be applied to one end surface of the pellicle frame to form an adhesive layer, and the pellicle membrane may be fixed on the adhesive layer.

The adhesive may be a known adhesive, such as a cellulose derivative, chlorinated polypropylene, polyamide adhesive, fluororesin adhesive, acrylic adhesive, epoxy resin, or polyimide adhesive.

Regarding Step 2) Next, an adhesive layer is provided on the end face of the opening of the pellicle frame on the opposite side to where the pellicle membrane is stretched. To form the adhesive layer, prepare the above-mentioned (meth)acrylic resin composition itself or a coating solution containing the (meth)acrylic resin composition, apply it to the end face of the opening of the pellicle frame, and dry. and cure to form an adhesive to form an adhesive layer.

The coating solution may further contain an organic solvent together with the resin composition. Specific examples of the solvent include the following compounds.
Aromatic solvents such as toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and 2-methyl-5-hexanone; ester solvents such as ethyl acetate and butyl acetate; methyl chloride, dichloromethane, dichloroethane, etc. Halogen solvent;
Ethylene glycol monoethyl ether, propylene glycol monomethyl ether,
Glycol ether solvents such as propylene glycol mono-n-propyl ether and propylene glycol; glycol ether carboxylate solvents such as propylene glycol monomethyl ether acetate.
One type of organic solvent may be used, or a mixture of two or more types can also be used.

The boiling point of the organic solvent (that is, the boiling point of the solvent used in the case of one kind, and the boiling point of the mixture in the case of two or more kinds) is preferably 150° C. or less. Since the thermal decomposition initiation temperature of the (meth)acrylic acid ester copolymer used as the copolymer (A) is around 150°C, if the boiling point of the organic solvent used is 150°C or lower, the copolymer (A) ) can be removed without heating to around 150° C., which can cause decomposition.

There is no particular limitation on the amount of the organic solvent, but it is usually preferably 0 parts by mass or more and 90 parts by mass or less, more preferably 0 parts by mass or more and 50 parts by mass or less, based on 100 parts by mass of the entire coating solution. preferable.

The (meth)acrylic resin composition or coating solution can be applied using any coating method, such as a spray coating method, a dipping coating method, a brush coating method, a spatula coating method, a roller coating method, This can be done by a casting coating method or the like. In the casting coating method, for example, after droplets are dropped onto the surface of a pellicle frame, the droplets can be spread with a jig to coat the pellicle to an even thickness.

The (meth)acrylic pressure-sensitive adhesive after application is dried and then cured by heating or light irradiation to form a pressure-sensitive adhesive. Drying and curing may be performed simultaneously. As heating conditions, the heating can be carried out at a temperature of 40° C. to 170° C. for 10 minutes to 2880 minutes. The light irradiation can be carried out under conditions of a wavelength of 254 nm to 365 nm and for 10 minutes to 30 minutes.

There is no particular limitation on the thickness of the adhesive thus obtained, but it is generally 0.2 mm or more and 0.8 mm or less. Further, from the viewpoint of enabling uniform application to the mask, the thickness is preferably 0.1 mm or more. The adhesive thus obtained is used as an adhesive layer.

Regarding Step 3) A pressure-sensitive adhesive layer is formed as described above to obtain a composite including a pellicle membrane, a pellicle frame, and a pressure-sensitive adhesive layer. The obtained composite is irradiated with ultraviolet rays having a wavelength of 193 nm or less, preferably 172 nm or more and 193 nm or less in an oxygen atmosphere.

The irradiated ultraviolet rays are not particularly limited as long as they have a wavelength of 193 nm or less. If the irradiated wavelength is 193 nm or less, the hardness of the outermost surface of the adhesive layer increases and mask-bondable functional groups (such as -OH and -COOH) is increased, which is thought to improve the load resistance. As the ultraviolet light with a wavelength of 193 nm or less, for example, an ArF excimer laser with a wavelength of 193 nm or VUV light with a wavelength of 172 nm can be used. Further, the amount of ultraviolet irradiation in step 3) can be generally 10 mJ/cm ² or more and 20 mJ/cm ² or less, preferably 13 mJ/cm ² or more and 15 mJ/cm ^{2 or} less.

Note that the ultraviolet irradiation in step 3) can be performed after carrying out the above steps 1) and 2). Therefore, step 3) is not only performed as part of the pellicle manufacturing process, but also can be performed by attaching the pellicle after steps 1) and 2) to a mask to create an exposure master plate, and performing exposure for lithography. can.

By step 3), the stress measured on the surface of the adhesive layer opposite to the surface in contact with the pellicle frame becomes 25 μN or more and 50 μN or less. As described above in connection with the pellicle of the present invention, this stress is the stress that occurs when the indentation depth is 4 μm, as measured by the nanoindentation method.

A protective film can also be attached to the adhesive layer of the pellicle. As the protective film, a polyester film or a polyethylene film that has been subjected to a release treatment with silicone or fluorine can be used.

Further, the adhesive layer can be further subjected to a flattening treatment. By performing the flattening treatment, the thickness of the adhesive layer can be adjusted and its flatness can be increased. For example, the pellicle can be flattened by sandwiching the pellicle between highly flat surface plates and by performing curing and molding in two steps. When molding is performed in two stages, the molding temperature in the second stage is preferably set higher than the molding temperature in the first stage. The molding temperature can be determined as appropriate depending on the composition of the adhesive, but the curing temperature in the first stage is preferably about 40°C to 150°C, and the molding temperature in the second stage is 60°C to 200°C. It is preferable that the temperature is about ℃.

Furthermore, in order to suppress the generation of outgas due to the adhesive layer, volatile components can also be removed. For example, volatile components can be removed by heating and drying the pellicle under conditions that do not cause deterioration of the adhesive layer or pellicle film, such as at 150° C. for 4 hours or at 120° C. for 20 hours.

3. Application of Pellicle The pellicle thus obtained is mounted on a mask via the adhesive layer. This can prevent foreign matter from adhering to the mask. When exposure light is focused on foreign matter adhering to the mask, it causes poor resolution to the wafer. Therefore, the pellicle is attached so as to cover the exposed area of the mask.

The mask is a glass substrate or the like on which a patterned light-shielding film is placed. The light shielding film may be a metal film such as Cr or MoSi.

Exposure light enters the mask from a portion other than the light-shielding film and passes through the pellicle film. Exposure light is normally incident approximately parallel to the normal line of the pellicle film, but may be incident obliquely to the normal line of the pellicle film.

Exposure light used in lithography, such as the process of forming circuit patterns drawn on semiconductor elements, is a short beam such as i-line (wavelength 365 nm) from a mercury lamp, KrF excimer laser (wavelength 248 nm), or ArF excimer laser (wavelength 193 nm). It can be excimer light of different wavelengths.
Note that when the exposure for lithography and the ultraviolet irradiation in step 3) of the above-described pellicle manufacturing method are performed simultaneously, the exposure light is an ArF excimer laser (wavelength: 193 nm).

As described above, in the present invention, the load resistance of the pellicle is improved when the stress generated when the pressure-sensitive adhesive layer of the pellicle is pushed in to a depth of 4 μm is within the range of 25 μN or more and 50 μN or less.

Hereinafter, the present invention will be explained in more detail based on Examples, but the present invention should not be construed as being limited by these Examples.

1. Materials The following materials were used in the following examples and comparative examples.

1-1. Copolymer (A)
RA-341: "Art Cure RA-341" manufactured by Negami Kogyo Co., Ltd. (multiple bond equivalent: 13,000 g/mol, weight average molecular weight: 80,000)
SEBS: Styrene-ethylene/butylene-styrene block copolymer (trade name “7A” (manufactured by Mitsui Chemicals), elastic modulus: 1.0×10 ⁵ to 2.0×10 ⁵ Pa, tan δ: 10 to 18°C )
SIPS: Styrene-isoprene-styrene block copolymer (trade name "HYBRAR 7125" (manufactured by Kuraray Co., Ltd.), solution viscosity: 30.0 to 90.0 mPa・S, volatile content 0.30% or less)

1-2. Hardening agent (B)
Photoradical polymerization initiator: “omnirad1173” manufactured by BASF
Thermal radical polymerization initiator: “Parkadox 12-XL25” manufactured by Kayaku Nourion Co., Ltd.

2. Preparation of resin composition Example 1: Preparation of resin composition 1 RA-341, which is a (meth)acrylic acid ester copolymer, was used as the polymer (A), and 100 parts by mass of RA-341 was subjected to photoradical polymerization. 0.01 part by mass of an initiator and 1 part by mass of a thermal radical polymerization initiator (diluted with xylene) were added and mixed to obtain a resin composition 1.

Comparative Example 1: Preparation of Resin Composition 2 A resin composition was prepared in the same manner as in Example 1 except that SIPS was used as the polymer (A), and Resin Composition 2 was obtained.

Comparative Example 2: Preparation of Resin Composition 3 A resin composition was prepared in the same manner as in Example 1 except that SEBS was used as the polymer (A), and Resin Composition 3 was obtained.

Comparative Example 3: Preparation of Resin Composition 4 A (meth)alkyl ester copolymer was prepared as follows. Put butyl acetate (30 parts by mass) into a reaction container, and add isobutyl acrylate/butyl acrylate/acrylic acid/2-hydroxyethyl acrylate/2.2-azobisisobutylnitrile (AIBN) = 40/56/1.5/2. A mixture of .5/1.0 (32 parts by mass) was charged and reacted at 60° C. for 10 hours under a nitrogen atmosphere. After the completion of the reaction, toluene (38 parts by mass) was added to obtain a (meth)alkyl ester copolymer.
0.25 parts by mass of an epoxy compound (a toluene solution of 1,3-bis(N,N-dicrycidylaminomethyl)cyclohexane) was added to the obtained (meth)alkyl ester copolymer, and the mixture was stirred to form a resin. Composition 4 was obtained.

3. Production of Pellicle Pellicles were produced using each of Resin Compositions 1 to 4 according to the following procedure.

3-1. Formation of Adhesive Layer Using a dispenser, apply a resin composition to the end face of an anodized aluminum pellicle frame (external dimensions: 149 mm x 122 mm, frame height: 5.8 mm, frame width: 2 mm). Coating was carried out at a coating temperature of 60°C. After drying this by heating (60°C, 30 minutes), the irradiation amount was adjusted to 654 mJ/ ^cm2 , and the resin composition was UV-cured at a wavelength of around 365 nm. Adhesive was applied to the end surface. Next, a PET separator was attached on top of the adhesive. In order to flatten the adhesive with a separator, the adhesive was heated and cured (120°C, 30 minutes) while pressing a flat glass plate over the separator to form an adhesive layer with a maximum thickness of 550 μm. .

3-2. Preparation of Pellicle A film was formed by spin coating a Cytop solution (trade name "CYTOP", manufactured by AGC, concentration 9%) on a glass substrate. Next, a peeling frame (made of plastic) is coated with an adhesive (trade name "AZ-2050", manufactured by Asahi Kagakusei Co., Ltd.), and is pasted on the film formed on the substrate, and the film is peeled off from the substrate. We made the pellicle membrane self-supporting.

An adhesive (trade name "CYAF", manufactured by AGC) was applied to the other end surface of the pellicle frame provided with the above adhesive layer. Next, the self-supporting pellicle membrane was uniformly attached to an adhesive to avoid wrinkles, and fused by UV irradiation. Finally, the unnecessary pellicle membrane protruding from the frame was cut off with a blade along the frame to obtain a pellicle, which was a composite including the pellicle membrane, pellicle frame, and adhesive layer.

4. UV irradiation 4-1. Attaching the pellicle to the mask A mask (manufactured by HOYA, 6025 substrate) was attached to the obtained pellicle using a pellicle mounter (manufactured by Matsushita Seiki). Specifically, the pellicle and mask were placed on a pellicle mounter, and the pellicle was crimped onto the mask. The pressure bonding conditions were room temperature, pressure of 10 kgF/cm ² , and 30 seconds.

4-2. Laser Irradiation The mask substrate to which the pellicle was attached was irradiated with an ArF excimer laser from the mask substrate side in an oxygen atmosphere to obtain a pellicle for evaluation to which the mask was attached. For irradiation with ArF excimer laser, an ArF irradiation device manufactured by COHERENT was used, and irradiation was performed at 15 J/cm ² .

5. Evaluation method 5-1. Stress in Adhesive Layer Stress, which is an index of the hardness of the adhesive layer of the pellicle, was measured by the following method.
After irradiation with the ArF excimer laser, the mask was peeled off from the evaluation pellicle to which the mask was attached, and the adhesive layer was exposed. A nanoindentation method was performed on the exposed adhesive layer using Hyditron TI Premier (manufactured by Bruker) as an apparatus. When the 20 μm conical diamond indenter came into contact with the adhesive layer, the indenter was pushed to a depth of 4 μm at a pushing speed of 0.8 μm/sec, and the stress generated at this time was measured.

5-2. Load Resistance Test Each evaluation pellicle and weight were assembled as shown in FIG. 1, and a load test was conducted under the conditions (temperature, load) shown in Table 1. Specifically, a weight 300 was fixed to the pellicle frame 122 of the evaluation pellicle 100 using epoxy resin 200 (product name: HiSuper 5, manufactured by Cemedine). Next, it was fixed in a clean oven set at an arbitrary temperature with the mask 110 facing upward, so that the evaluation pellicle 100 and the weight 300 were suspended, and left for 24 hours. It was observed whether the peri-adhesive layer 121 peeled off from the mask 110 and the pellicle part 120 fell within 24 hours, and evaluation was made according to the following criteria.
○: No fall within 24 hours ×: Fall within 24 hours

The evaluation results are shown in Table 1 together with the test conditions of the load resistance test.

As is clear from Table 1 above, an adhesive containing a (meth)acrylic adhesive that is a cured product of a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B). The pellicle of Example 1, in which the stress of the adhesive layer was within the range of 25 μN or more and 50 μN or less, exhibited good load resistance under a load of 500 to 800 g at a temperature of 50°C (load resistance test). 1, 3, 4). In addition, good load resistance was exhibited even under the conditions of a temperature of 70° C. and a load of 500 g (load resistance test 2).

On the other hand, in Comparative Example 1, which has an adhesive layer containing an adhesive that is a cured product of a resin composition that does not contain the (meth)acrylic acid ester copolymer (A), and the stress of the adhesive layer is less than 25 μN. The pellicle had low load resistance even under conditions of a temperature of 50° C. and a load of 500 g (load resistance test 5). Furthermore, the pellicle of Comparative Example 3 has an adhesive layer containing an adhesive that is a cured product of a resin composition containing the (meth)acrylic acid ester copolymer (A), but the stress of the adhesive layer is less than 25 μN. Also, the load resistance was low even under the conditions of a temperature of 50° C. and a load of 500 g (load resistance test 7). Furthermore, the pellicle of Comparative Example 2 in which the stress of the adhesive layer exceeded 50 μN also had low load resistance under conditions of a temperature of 50° C. and a load of 500 g (load resistance test 6). This is considered to be because the adhesive layer was cured too much and the adhesion was reduced.

According to the present invention, it is possible to provide a pellicle that has high adhesion to a substrate and excellent load resistance, and a method for manufacturing the same. By using the pellicle of the present invention, it becomes possible to perform lithography using short wavelength exposure light without causing problems such as the pellicle peeling off from the mask.

100 Pellicle for evaluation 110 Mask 120 Pellicle part 121 Adhesive layer 122 Pellicle frame (including pellicle film)
200 Epoxy resin 300 Weight

Claims (6)

pellicle frame and
a pellicle membrane stretched over one end surface of the pellicle frame;
A pellicle comprising an adhesive layer provided on the other end surface of the pellicle frame,
The adhesive layer includes a (meth)acrylic adhesive that is a cured product of a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B),
The stress measured on the surface of the adhesive layer opposite to the surface in contact with the pellicle frame is 25 μN or more and 50 μN or less, and the stress is measured by a nanoindentation method when the indentation depth is 4 μm. A pellicle is a stress that sometimes occurs. The pellicle according to claim 1, wherein the (meth)acrylic ester copolymer (A) has a structural unit derived from a (meth)acrylic ester and a side chain consisting of a carbon-carbon multiple bond-containing group. The pellicle according to claim 2, wherein the carbon-carbon multiple bond-containing group is a carbon-carbon double bond-containing group. The pellicle according to any one of claims 1 to 3, wherein the curing agent (B) is a radical polymerization initiator. The pellicle according to claim 4, wherein the radical polymerization initiator is a thermal radical polymerization initiator. A method for manufacturing a pellicle according to any one of claims 1 to 5, comprising:
a step of stretching a pellicle membrane on one end surface of the pellicle frame;
providing an adhesive layer on the other end surface of the pellicle frame using a resin composition containing a (meth)acrylic acid ester copolymer (A) and a curing agent (B);
irradiating the composite including the pellicle film, the pellicle frame, and the adhesive layer with ultraviolet rays with a wavelength of 193 nm or less in an oxygen atmosphere,
By the step of irradiating the ultraviolet rays, the stress measured on the surface of the adhesive layer opposite to the surface in contact with the pellicle frame becomes 25 μN or more and 50 μN or less, and the stress is measured by a nanoindentation method. , is the stress that occurs when the indentation depth is 4 μm,
How to make a pellicle.

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