WO2016120944A1

WO2016120944A1 - Adhesion layer-forming composition, method of manufacturing cured product pattern, method of manufacturing optical component, method of manufacturing circuit board, method of manufacturing imprinting mold, and device component

Info

Publication number: WO2016120944A1
Application number: PCT/JP2015/006471
Authority: WO
Inventors: Takeshi Honma; Toshiki Ito; Tomonori OTANI
Original assignee: Canon Kabushiki Kaisha
Priority date: 2015-01-30
Filing date: 2015-12-25
Publication date: 2016-08-04

Abstract

An adhesion layer-forming composition contains a compound (A) containing either or both of alkoxyalkyl and alkylol groups, the number of either of the alkoxyalkyl and alkylol groups per molecule or the number of the alkoxyalkyl and alkylol groups per molecule being at least 5 in total, and a compound (B) containing at least two thiol groups per molecule.

Description

ADHESION LAYER-FORMING COMPOSITION, METHOD OF MANUFACTURING CURED PRODUCT PATTERN, METHOD OF MANUFACTURING OPTICAL COMPONENT, METHOD OF MANUFACTURING CIRCUIT BOARD, METHOD OF MANUFACTURING IMPRINTING MOLD, AND DEVICE COMPONENT

The present invention relates to an adhesion layer-forming composition, a method of manufacturing a cured product pattern, a method of manufacturing an optical component, a method of manufacturing a circuit board, a method of manufacturing an imprinting mold, and a device component.

In semiconductor devices, microelectromechanical systems (MEMSs), and the like, requirements for microfabrication have been increasing. In particular, a photonanoimprinting technique has been attracting attention.

In the photonanoimprinting technique, a photocurable composition (resist) is cured in such a state that a mold having a surface with a fine irregular pattern is pressed against a base member, such as a substrate (wafer), coated with the photocurable composition. This transfers the irregular pattern of the mold to a cured film of the photocurable composition, thereby forming the irregular pattern on the base member. The photonanoimprinting technique is capable of forming a fine structure on the order of several nanometers.

In the photonanoimprinting technique, a photocurable composition is applied to a pattern-forming region of the base member (a placement step). Next, the photocurable composition is molded using a patterned mold (a mold-contacting step). The photocurable composition is cured by irradiating the photocurable composition with light (a light irradiation step) and is then demolded (a demolding step). Through these steps, a resin pattern (photocured product) having a predetermined shape is formed on the base member.

In the demolding step of the photonanoimprinting technique, the adhesion between the photocurable composition and the base member is important. This is because when the adhesion between the photocurable composition and the base member low, portions of a photocured product obtained by curing the photocurable composition adhere to the mold and are peeled off in the operation of removing the mold in the demolding step, that is, pattern peeling defects are caused in some cases.

Hitherto, the following technique has been proposed as a technique for improving the adhesion between a photocurable composition and a base member: a technique in which an adhesion layer for sticking the photocurable composition and the base member is formed between the photocurable composition and the base member (PTL 1).

Japanese Patent Laid-Open No. 2013-202982

In the technique disclosed in PTL 1, the adhesion layer is formed using a composition containing a curable base resin and a urea crosslinking agent. However, since the composition contains the urea crosslinking agent, the curing of the composition is insufficient to form the adhesion layer. Therefore, there is a problem in that the adhesion between the photocurable composition and the base member cannot be sufficiently increased and pattern peeling defects occur.

In view of the above circumstances, the present invention provides an adhesion layer-forming composition capable of suppressing the occurrence of pattern peeling defects.

The present invention provides an adhesion layer-forming composition containing a compound (A) containing either or both of alkoxyalkyl and alkylol groups, the number of either of the alkoxyalkyl and alkylol groups per molecule or the number of the alkoxyalkyl and alkylol groups per molecule being at least 5 in total, and a compound (B) containing at least two thiol groups per molecule.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawing.

Fig. 1A is a schematic sectional view showing a method of manufacturing a cured product pattern according to an embodiment of the present invention. Fig. 1B is a schematic sectional view showing the method of manufacturing the cured product pattern. Fig. 1C is a schematic sectional view showing the method of manufacturing the cured product pattern. Fig. 1D is a schematic sectional view showing the method of manufacturing the cured product pattern. Fig. 1E is a schematic sectional view showing the method of manufacturing the cured product pattern. Fig. 1F is a schematic sectional view showing the method of manufacturing the cured product pattern. Fig. 1G is a schematic sectional view showing the method of manufacturing the cured product pattern. Fig. 1H is a schematic sectional view showing the method of manufacturing the cured product pattern.

Embodiments of the present invention will now be described in detail. The present invention is not limited to the embodiments. Modifications, improvements, and the like that are made to the embodiments on the basis of knowledge of those skilled in the art without departing from the gist of the present invention are included in the scope of the present invention.

An adhesion layer-forming composition 100 according to an embodiment of the present invention is one for forming an adhesion layer 101 between a base member 102 and a photocurable composition 103. The adhesion layer-forming composition 100 contains a compound (A) containing either or both of alkoxyalkyl and alkylol groups, the number of either of the alkoxyalkyl and alkylol groups per molecule or the number of the alkoxyalkyl and alkylol groups per molecule being at least 5 in total, and a compound (B) containing at least two thiol groups per molecule.

The adhesion layer-forming composition 100 is preferably used in such a manner that the adhesion layer-forming composition 100 is placed on the base member 102 and is cured and a photocured product is thereby formed. A stack including the adhesion layer 101, which is obtained by curing the adhesion layer-forming composition 100, and the base member 102 can be preferably used as a base member for obtaining a photocured product 109 obtained by placing the photocurable composition 103 on the stack. The adhesion layer-forming composition 100 can be used as an adhesion layer-forming composition for imprinting and is particularly useful as an adhesion layer-forming composition for photonanoimprinting.

Components contained in the adhesion layer-forming composition 100 are described below in detail.

Compound (A)

The compound (A) contains either or both of the alkoxyalkyl and alkylol groups (hereinafter referred to as "functional groups a") and the number of either of the alkoxyalkyl and alkylol groups per molecule or the number of the alkoxyalkyl and alkylol groups per molecule is at least 5 in total.

The functional groups a contained in the compound (A) are those that react with the thiol groups contained in the compound (B) in an adhesion layer-forming step below. Therefore, bonds are formed between the compound (A) and the compound (B). Since the compound (A) contains the functional groups a, each molecule of the compound (A) can be bonded to a plurality of molecules of the compound (B). Since each molecule of the compound (A) can be bonded to molecules of the compound (B), a structure (crosslinked structure) in which compounds forming the adhesion layer 101 are crosslinked to each other can be formed.

The reaction between the functional groups a contained in the compound (A) and the thiol groups contained in the compound (B) is preferably caused by a heating process in the adhesion layer-forming step.

The amount of the free, unreacted compound (A) or (B) not bonded to the base member 102 can be reduced in such a manner that the adhesion layer 101 is formed so as to have the crosslinked structure as described above. This allows the adhesion layer 101 to have increased strength.

When the unreacted compounds (A) and (B) are present in the adhesion layer 101 in a free state, the unreacted compounds (A) and (B) may possibly be dissolved in the photocurable composition 103 in a step of placing the photocurable composition 103. As a result, the composition of the photocurable composition 103 varies and therefore characteristics of the photocurable composition 103 vary, thereby causing, for example, pattern peeling defects or the like in the photocured product 109, which is obtained by curing the photocurable composition 103.

However, using the adhesion layer-forming composition 100 enables the amount of the free compound (A) or (B) not bonded to the base member 102 to be more significantly reduced than ever. This enables the dissolution of the compound (A) or (B) in the photocurable composition 103 to be significantly suppressed in the step of placing the photocurable composition 103. As a result, the occurrence of pattern peeling defects or the like in the photocured product 109 can be suppressed.

The functional groups a contained in the compound (A) may form interactions or chemical bonds such as covalent bonds, ionic bonds, hydrogen bonds, or intermolecular forces with functional groups present on the base member 102. When the base member 102 has, for example, hydroxy groups such as silanol groups on the surface thereof, a dealcoholization reaction occurs between the alkoxyalkyl groups and the silanol groups. Therefore, covalent bonds can be formed between the compound (A) and the base member 102. This allows the adhesion between the adhesion layer 101 and the base member 102 to be increased.

The compound (A) is preferably a compound represented by Formula (1) below.

In Formula (1), R₁ to R₆ independently represent a hydrogen atom, an alkyl group, an alkoxyalkyl group, or an alkylol group and at least five of R₁ to R₆ are alkoxyalkyl groups or alkylol groups.

The compound represented by Formula (1) is a melamine derivative containing a triazine ring at the center of its structure. That is, the compound represented by Formula (1) has a structure in which each nitrogen atom is bonded to a corresponding one of the 2-, 4-, and 6-positions of 1,3,5- triazine. The compound represented by Formula (1) contains five or six functional groups a. That is, the compound represented by Formula (1) contains a larger number of functional groups a as compared to urea compounds such as glycoluril derivatives.

A urea compound contains electron-withdrawing oxygen atoms in its molecule. Therefore, the reactivity of functional groups a contained in a functional groups a-containing urea compound with thiol groups or the like tends to be lower as compared to compounds containing no electron-withdrawing oxygen atoms in its molecule. However, the triazine ring is a nucleus in the compound represented by Formula (1) and contains no electron-withdrawing oxygen atoms in its structure. Therefore, the functional groups a contained in the compound represented by Formula (1) probably have higher reactivity as compared to functional groups a in such a urea compound.

From the above, using the compound (A), which is the compound represented by Formula (1), allows the adhesion layer-forming composition 100 to have enhanced curability and also allows the adhesion layer 101, which is formed using the adhesion layer-forming composition 100, to have increased strength.

The type of the alkoxyalkyl or alkylol groups contained in the compound (A) is not particularly limited. The alkoxyalkyl groups are preferably methoxymethyl groups and the alkylol groups are preferably methylol groups. Using functional groups with low formula weight as the alkoxyalkyl or alkylol groups allows the adhesion layer 101 to have increased crosslink density per unit mass and therefore allows the adhesion layer 101 to have increased strength.

Examples of the compound (A) include, but are not limited to, pentamethoxymethylmelamine, hexamethoxymethylmelamine, (hydroxymethyl)pentakis(methoxymethyl)melamine, hexaethoxymethylmelamine, hexabutoxymethylmelamine, pentamethylolmelamine, and hexamethylolmelamine.

The compound (A) may be composed of a single type of compound or multiple types of compounds.

Compound (B)

The compound (B) is one containing at least two thiol groups in its molecule.

The thiol groups contained in the compound (B) are functional groups reacting with the functional groups a contained in the compound (A) as described above. Therefore, bonds are formed between the compound (A) and the compound (B). Since the compound (B) contains the thiol groups, each molecule of the compound (B) can be bonded to a plurality of molecules of the compound (A). Since each molecule of the compound (B) can be bonded to molecules of the compound (A), a structure (crosslinked structure) in which compounds forming the adhesion layer 101 are crosslinked to each other can be formed.

The amount of the free, unreacted compound (A) or (B) not bonded to the base member 102 can be reduced in such a manner that the adhesion layer 101 is formed so as to have the crosslinked structure as described above. This allows the base member 102 to have increased strength and enables the dissolution of the compound (A) or (B) in the photocurable composition 103 to be significantly suppressed in the step of placing the photocurable composition 103. As a result, the occurrence of pattern peeling defects or the like in the photocured product 109 can be suppressed.

The thiol groups contained in the compound (B) can form interactions or chemical bonds such as covalent bonds, hydrogen bonds, or intermolecular forces with the functional groups present on the base member 102. This allows the adhesion between the adhesion layer 101 and the base member 102 to be increased.

The thiol groups contained in the compound (B) are covalently bonded to a polymerizable compound contained in the photocurable composition 103 through chain transfer reactions between the thiol groups contained in the compound (B) and radicals generated in the photocurable composition 103 in a light irradiation step below. This allows the adhesion between the adhesion layer 101 and the photocurable composition 103 or the photocured product 109 to be increased. The adhesion layer 101 forms the chemical bonds or the interactions with the base member 102 as described above and therefore can increase the adhesion between the base member 102 and the photocurable composition 103 or the photocured product 109.

In order to exhibit the above effects, the number of the thiol groups contained in the compound (B) is preferably large, more preferably at least 3, and further more preferably at least 4. When the number of the thiol groups contained in the compound (B) is at least 3, a crosslinked structure formed by the compound (B) is three-dimensional and the adhesion layer 101 has increased strength. Furthermore, the compound (B), the compound (A), and the base member 102 are likely to be bonded to each other. As the number of the thiol groups contained in the compound (B) is larger, the above effects are more significant. Therefore, the number of the thiol groups contained in the compound (B) is preferably at least 4.

The compound (B) is preferably a primary thiol. When the compound (B) is the primary thiol, steric hindrance around the thiol groups contained in the compound (B) can be reduced. As a result, the reactivity of the thiol groups contained in the compound (B) can be increased and curability of the adhesion layer-forming composition 100 can be enhanced.

Examples of the compound (B) include, but are not limited to, difunctional thiol compounds such as 1,6-hexanedithiol, 1,8-octanedithiol, 1,10-decanedithiol, 1,4-butanediol bis(thioglycolate), and 1,4-bis(3-mercaptobutyryloxy)butane; trifunctional thiol compounds such as 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(3-mercaptopropionate), and pentaerythritol tris(3-mercaptobutyrate); and tetrafunctional thiol compounds such as pentaerythritol tetrakis(mercaptoacetate), pentaerythritol tetrakis(3-mercaptobutyrate), and pentaerythritol tetrakis(3-mercaptopropionate).

The compound (B) may be a single type of compound or multiple types of compounds.

Blending ratio of compound (A) and compound (B)

When the blending ratio of the compound (A) or (B) in the adhesion layer-forming composition 100 is extremely small, the adhesion layer 101 has reduced crosslink density, insufficient strength, and insufficient curability. Thus, the ratio α:β is preferably 1:9 to 9:1 and more preferably 1:4 to 4:1, where α (%) is the weight fraction of the compound (A) and β (%) is the weight fraction of the compound (B) when the whole of the adhesion layer-forming composition 100 is 100% by weight. That is, the proportion α/β is preferably 0.11 to 9 and more preferably 0.25 to 4. Though the optimum blending ratio of each of the compound (A) and the compound (B) depends on the number, molecular weight, and reactivity of functional groups of the compounds (A) and (B), adjusting the blending ratio substantially within the above range allows the adhesion layer-forming composition 100 to have enhanced curability.

The blending ratio (the sum of α and β) of the compounds (A) and (B) in the adhesion layer-forming composition 100 can be appropriately adjusted depending on the viscosity of the adhesion layer-forming composition 100, the target thickness of the adhesion layer 101, or the like. The sum of α and β is preferably 0.01 to 10 or less, more preferably 0.1 to 10, and further more preferably 0.1 to 7. Adjusting the blending ratio of the compounds (A) and (B) in the adhesion layer-forming composition 100 within the above range allows the adhesion layer-forming composition 100 to have reduced viscosity and also allows the adhesion layer 101 to have reduced thickness.

Volatile solvent (C)

The adhesion layer-forming composition 100 further contains a volatile solvent (C) (hereinafter simply referred to as the "solvent (C)"). Since the adhesion layer-forming composition 100 contains the solvent (C), the viscosity of the adhesion layer-forming composition 100 can be reduced. As a result, application properties of the adhesion layer-forming composition 100 to the base member 102 can be enhanced.

The solvent (C) is not particularly limited and may dissolve the compound (A) and the compound (B). The solvent (C) preferably has a boiling point of 80°C to 200°C at atmospheric pressure. The solvent (C) is preferably an organic solvent having at least one of a hydroxy group, an ether structure, an ester structure, and a ketone structure. The solvent (C) is excellent in dissolving the compound (A) and the compound (B) and has excellent wettability to the base member 102.

Examples of the solvent (C) include alcohol solvents such as propyl alcohol, isopropyl alcohol, and butyl alcohol; ether solvents such as ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol monoethyl ether, ethylene glycol diethyl ether, ethylene glycol monobutyl ether, and propylene glycol monomethyl ether; ester solvents such as butyl acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, and propylene glycol monomethyl ether acetate; and ketone solvents such as methyl isobutyl ketone, diisobutyl ketone, cyclohexanone, 2-heptanone, γ-butyrolactone, and ethyl lactate. These solvents may be used alone or in combination. In particular, propylene glycol monomethyl ether acetate or a mixture containing propylene glycol monomethyl ether acetate is preferable from the viewpoint of application properties.

The blending ratio of the solvent (C) in the adhesion layer-forming composition 100 can be adjusted depending on the viscosity of the compounds (A) and (B), application properties of the compounds (A) and (B), the thickness of the adhesion layer 101, or the like. The blending ratio of the solvent (C) in the adhesion layer-forming composition 100 is preferably 70% by mass or more, more preferably 90% by mass or more, and further more preferably 95% by mass or more with respect to the amount of the adhesion layer-forming composition 100. As the blending ratio of the solvent (C) in the adhesion layer-forming composition 100 is larger, the thickness of the adhesion layer 101 can be made smaller, which is preferable for adhesion layer-forming compositions for imprinting. When the blending ratio of the solvent (C) in the adhesion layer-forming composition 100 is less than 70% by mass, sufficient application properties cannot be achieved in some cases. The upper limit of the blending ratio of the solvent (C) is not particularly limited. The upper limit of the blending ratio of the solvent (C) is preferably 99.9% by mass or less and more preferably 99% by mass or less.

Another component (D)

The adhesion layer-forming composition 100 may further contain a component (D) in addition to the compound (A), the compound (B), and the solvent (C) depending on various purposes unless effects of the present invention are impaired. Examples of the component (D) include surfactants, crosslinking agents, polymer components, oxidation inhibitors, and polymerization inhibitors. The adhesion layer-forming composition 100 is placed on the base member 102 and is then cured by heating with the solvent (C) evaporated, whereby the thickness of the adhesion layer 101 can be reduced. Therefore, it is preferable that the adhesion layer-forming composition 100 does not contain any photopolymerization initiator used for the purpose of curing the adhesion layer-forming composition 100 by photoirradiation. If the adhesion layer-forming composition 100 contains a photopolymerization initiator, then photopolymerization occurs in the course of forming the adhesion layer 101 to cure the adhesion layer-forming composition 100 before the solvent (C) volatilizes completely; hence, the adhesion layer 101 may possibly have increased thickness.

Viscosity of adhesion layer-forming composition

The viscosity of the adhesion layer-forming composition 100 depends on the type and blending ratio of components, such as the compound (A), the compound (B), and the solvent (C). The viscosity of the adhesion layer-forming composition 100 is preferably 0.5 millipascal-seconds to 20 millipascal-seconds, more preferably 1 millipascal-second to 10 millipascal-seconds, and further more preferably 1 millipascal-second to 5 millipascal-seconds at 23°C.

When the viscosity of the adhesion layer-forming composition 100 is 20 millipascal-seconds or less, application properties of the adhesion layer-forming composition 100 to the base member 102 are excellent. Therefore, the thickness of a layer of the adhesion layer-forming composition 100 placed on the base member 102 can be readily adjusted.

Impurities trapped in adhesion layer-forming composition

The adhesion layer-forming composition 100 preferably contains substantially no impurities. The term "impurities" as used herein refers to those other than the compound (A), the compound (B), the solvent (C), and the component (D). In the case where the adhesion layer-forming composition 100 is used in a nanoimprinting process, the adhesion layer-forming composition 100 particularly preferably contains none of particles and solid components. The term "particles" as used herein typically refers to gelled or solid particulate substances with a size (diameter) of several nanometers to several micrometers. Thus, the content of particles with a size of greater than 0.2 μm in the adhesion layer-forming composition 100 is preferably 0% or more and less than 3% by mass when the whole of the adhesion layer-forming composition 100 is 100% by mass.

Thus, the adhesion layer-forming composition 100 is preferably obtained through a purification step. In the purification step, filtration or the like is preferably performed using a filter.

In the case of performing filtration using a filter, a mixture obtained by mixing the compound (A), the compound (B), the solvent (C), and the component (D), which is added as required, is preferably filtered through a filter with a pore size of, for example, 0.001 μm to 5.0 μm. The mixture is more preferably filtered through a filter with a pore size of 0.001 μm to 0.2 μm. It is more preferable that filtration is performed using a filter in multiple steps or is repeated using a filter multiple times. A filtrate may be filtered again. A plurality of filters with different pore sizes may be used for filtration. A filter used for filtration is not particularly limited and may be made of a polyethylene resin, a polypropylene resin, a fluorinated resin, a nylon resin, or the like.

Impurities, such as particles, trapped in the adhesion layer-forming composition 100 can be removed through the purification step. This allows defects to be prevented from being carelessly caused in the adhesion layer 101, which is obtained by applying the adhesion layer-forming composition 100.

In the case of using the adhesion layer-forming composition 100 to manufacture a circuit board for use in semiconductor devices such as semiconductor integrated circuits, the trapping of impurities (metal impurities) containing metal atoms in the adhesion layer-forming composition 100 is preferably avoided if possible. This is because the impurities, such as metals, are prevented from inhibiting the operation of the circuit board. In this case, the concentration of metal impurities in the adhesion layer-forming composition 100 is preferably 10 ppm or less and more preferably 100 ppb or less.

Thus, the adhesion layer-forming composition 100 is preferably prepared without being in contact with metal in preparation steps thereof. That is, in the case where raw materials of the compound (A), the compound (B), the solvent (C), and the component (D), which is added as required, are weighed, are formulated, and are mixed together, no metal weighing tool or container is preferably used. Furthermore, in the above purification step, filtration is preferably performed using a metal impurity-removing filter. The metal impurity-removing filter is not particularly limited and may be a filter made of cellulose, diatomaceous earth, an ion-exchange resin, or the like. The metal impurity-removing filter is preferably used after being cleaned. A cleaning method is preferably as follows: washing with ultra-pure water, washing with alcohol, and co-washing with the adhesion layer-forming composition 100 are performed in that order.

Photocurable composition

The photocurable composition 103, which is used together with the adhesion layer 101 formed from the adhesion layer-forming composition 100, usually contains a component (E) that is a polymerizable compound and a component (F) that is a photopolymerization initiator.

Component (E): polymerizable compound

The component (E) is the polymerizable compound. The term "polymerizable compound" as used herein refers to a compound that reacts with polymerization factors (radicals and the like) generated from the photopolymerization initiator (component (F)) to form a film made of a polymeric compound (polymer) by a chain reaction (polymerization reaction).

The component (E) may be composed of a single type of polymerizable compound or multiple types of polymerizable compounds.

The polymerizable compound is, for example, a radically polymerizable compound. The radically polymerizable compound is preferably a compound containing one or more acryloyl or methacryloyl groups, that is, a (meth)acrylic compound.

Thus, the component (E), which is the polymerizable compound, preferably contains the (meth)acrylic compound. A main ingredient of the component (E) is more preferably the (meth)acrylic compound. The component (E) is most preferably the (meth)acrylic compound. As used herein, the expression "a main ingredient of the component (E) is the (meth)acrylic compound" means that 90% by weight or more of the component (E) is the (meth)acrylic compound.

When the radically polymerizable compound is composed of multiple types of compounds containing one or more acryloyl or methacryloyl groups, the radically polymerizable compound preferably contains a monofunctional (meth)acrylate monomer and a polyfunctional (meth)acrylate monomer. This is because a cured film with high strength is obtained using the monofunctional (meth)acrylate monomer and the polyfunctional (meth)acrylate monomer in combination.

Examples of a monofunctional (meth)acrylic compound containing one or more acryloyl or methacryloyl groups include, but are not limited to, phenoxyethyl (meth)acrylate, phenoxy-2-methylethyl (meth)acrylate, phenoxyethoxyethyl (meth)acrylate, 3-phenoxy-2-hydroxypropyl (meth)acrylate, 2-phenylphenoxyethyl (meth)acrylate, 4-phenylphenoxyethyl (meth)acrylate, 3-(2-phenylphenyl)-2-hydroxypropyl (meth)acrylate, (meth)acrylates of EO-modified p-cumylphenol, 2-bromophenoxyethyl (meth)acrylate, 2,4-dibromophenoxyethyl (meth)acrylate, 2,4,6-tribromophenoxyethyl (meth)acrylate, EO-modified phenoxy (meth)acrylate, PO-modified phenoxy (meth)acrylate, polyoxyethylene nonylphenyl ether (meth)acrylate, isobornyl (meth)acrylate, 1-adamantyl (meth)acrylate, 2-methyl-2-adamantyl (meth)acrylate, 2-ethyl-2-adamantyl (meth)acrylate, bornyl (meth)acrylate, tricyclodecanyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, cyclohexyl (meth)acrylate, 4-butylcyclohexyl (meth)acrylate, acryloyl morpholine, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, amyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, benzyl (meth)acrylate, 1-naphthylmethyl (meth)acrylate, 2-naphthylmethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, butoxyethyl (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, methoxyethylene glycol (meth)acrylate, ethoxyethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, diacetone (meth)acrylamide, isobutoxymethyl (meth)acrylamide, N,N-dimethyl (meth)acrylamide, t-octyl (meth)acrylamide, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 7-amino-3,7-dimethyloctyl (meth)acrylate, N,N-diethyl (meth)acrylamide, and N,N-dimethylaminopropyl (meth)acrylamide.

Examples of the monofunctional (meth)acrylic compound include, but are not limited to, products such as ARONIX M101, ARONIX M102, ARONIX M110, ARONIX M111, ARONIX M113, ARONIX M117, ARONIX M5700, TO1317, ARONIX M120, ARONIX M150, and ARONIX M156 commercially available from Toagosei Co., Ltd.; products such as MEDOL 10, MIBDOL 10, CHDOL 10, MMDOL 30, MEDOL 30, MIBDOL 30, CHDOL 30, LA, IBXA, 2-MTA, HPA, Viscoat #150, Viscoat #155, Viscoat #158, Viscoat #190, Viscoat #192, Viscoat #193, Viscoat #220, Viscoat #2000, Viscoat #2100, and Viscoat #2150 commercially available from Osaka Organic Chemical Industry Ltd.; products such as Light Acrylate BO-A, Light Acrylate EC-A, Light Acrylate DMP-A, Light Acrylate THF-A, Light Acrylate HOP-A, Light Acrylate HOA-MPE, Light Acrylate HOA-MPL, Light Acrylate PO-A, Light Acrylate P-200A, Light Acrylate NP-4EA, Light Acrylate NP-8EA, and EPOXY ESTER M-600A commercially available from Kyoeisha Chemical Co., Ltd.; products such as KAYARAD TC110S, KAYARAD R-564, and KAYARAD R-128H commercially available from Nippon Kayaku Co., Ltd.; products such as NK Ester AMP-10G and NK Ester AMP-20G commercially available from Shin-Nakamura Chemical Co., Ltd.; products such as FA-511A, FA-512A, and FA-513A commercially available from Hitachi Chemical Co., Ltd.; products such as PHE, CEA, PHE-2, PHE-4, BR-31, BR-31M, and BR-32 commercially available from Dai-ichi Kogyo Seiyaku Co., Ltd.; VP commercially available from BASF; and products such as ACMO, DMMA, and DMAPAA commercially available from Kohjin Co., Ltd.

Examples of a polyfunctional (meth)acrylic compound containing two or more acryloyl or methacryloyl groups include, but are not limited to, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate, PO-modified trimethylolpropane tri(meth)acrylate, EO-PO-modified trimethylolpropane tri(meth)acrylate, dimethyloltricyclodecane diacrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-adamantanedimethanol diacrylate, o-xylylene di(meth)acrylate, m-xylylene di(meth)acrylate, p-xylylene di(meth)acrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate, tris(acryloyloxy) isocyanurate, bis(hydroxymethyl)tricyclodecane di(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, EO-modified 2,2-bis(4-((meth)acryloxy)phenyl)propane, PO-modified 2,2-bis(4-((meth)acryloxy)phenyl)propane, and EO-PO-modified 2,2-bis(4-((meth)acryloxy)phenyl)propane.

Examples of the polyfunctional (meth)acrylic compound include, but are not limited to, products such as YUPIMER UV, YUPIMER SA1002, and YUPIMER SA2007 commercially available from Mitsubishi Chemical Corporation; products such as Viscoat #195, Viscoat #230, Viscoat #215, Viscoat #260, Viscoat #335HP, Viscoat #295, Viscoat #300, Viscoat #360, Viscoat #700, Viscoat GPT, and Viscoat 3PA commercially available from Osaka Organic Chemical Industry Ltd.; products such as Light Acrylate 4EG-A, Light Acrylate 9EG-A, Light Acrylate NP-A, Light Acrylate DCP-A, Light Acrylate BP-4EA, Light Acrylate BP-4PA, Light Acrylate TMP-A, Light Acrylate PE-3A, Light Acrylate PE-4A, and Light Acrylate DPE-6A commercially available from Kyoeisha Chemical Co., Ltd.; products such as A-DCP, A-HD-N, A-NOD-N, and A-DOD-N commercially available from Shin-Nakamura Chemical Co., Ltd.; products such as KAYARAD PET-30, KAYARAD TMPTA, KAYARAD R-604, KAYARAD DPHA, KAYARAD DPCA-20, KAYARAD DPCA-30, KAYARAD DPCA-60, KAYARAD DPCA-120, KAYARAD HX-620, KAYARAD D-310, and KAYARAD 330 commercially available from Nippon Kayaku Co., Ltd.; products such as ARONIX M208, ARONIX M210, ARONIX M215, ARONIX M220, ARONIX M240, ARONIX M305, ARONIX M309, ARONIX M310, ARONIX M315, ARONIX M325, and ARONIX M400 commercially available from Toagosei Co., Ltd.; and products such as Ripoxy VR-77, Ripoxy VR-60, and Ripoxy VR-90 commercially available from Showa Denko K.K.

In the above compounds, the term "(meth)acrylate" refers to an acrylate or a methacrylate, containing an alcohol residue, equivalent to the acrylate; the term "(meth)acryloyl group" refers to an acryloyl group or a methacryloyl group, containing an alcohol residue, equivalent to the acryloyl group; EO represents ethylene oxide; the term "EO-modified compound A" refers to a compound in which a (meth)acrylic acid residue and alcohol residue of a compound A are linked to each other through a block structure composed of ethylene oxide groups; PO represents propylene oxide; and the term "PO-modified compound B" refers to a compound in which a (meth)acrylic acid residue and alcohol residue of a compound B are linked to each other through a block structure composed of propylene oxide groups.

Component (F): photopolymerization initiator

The component (F) is the photopolymerization initiator. The term "photopolymerization initiator" as used herein refers to a compound that absorbs light with a predetermined wavelength to generate polymerization factors (radicals). In particular, the photopolymerization initiator is a polymerization initiator (radical generator) that absorbs light (an infrared ray, a visible ray, an ultraviolet ray, a far infrared ray, an X-ray, a charged-particle beam such as an electron beam, or a radiation) to generate radicals. In more particular, the photopolymerization initiator is a polymerization initiator that absorbs light with a wavelength of, for example, 150 nm to 400 nm to generate radicals.

The component (F) may be composed of a single type of photopolymerization initiator or multiple types of photopolymerization initiators.

Examples of the radical generator include, but are not limited to, 2,4,5-triarylimidazole dimers such as a 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, a 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, a 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, a 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, and a 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer; benzophenone derivatives such as benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone (Michler's ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxyl-4'-dimethylaminobenzophenone, 4-chlorobenzophenone, 4,4'-dimethoxylbenzophenone, and 4,4'-diaminobenzophenone; α-aminoaromatic ketone derivatives such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone -1 and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propane-1-one; quinones such as 2-ethylanthraquinone, phenanthrenequinone, 2-t-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, and 2,3-dimethylanthraquinone; benzoin ether derivatives such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; benzoin derivatives such as benzoin, methylbenzoin, ethylbenzoin, and propylbenzoin; benzil derivatives such as benzil dimethyl ketal; acridine derivatives such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; N-phenylglycine derivatives such as N-phenylglycine; acetophenone derivatives such as acetophenone, 3-methylacetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, and 2,2-dimethoxy-2-phenylacetophenone; thioxanthone derivatives such as thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, and 2-chlorothioxanthone; acylphosphine oxide derivatives such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide; oxime ester derivatives such as 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)] and ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-, 1-(O-acetyloxime); xanthone; fluorenone; benzaldehyde; fluorene; anthraquinone; triphenylamine; carbazole; 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-1-one; and 2-hydroxy-2-methyl-1-phenyl propane-1-one. The 2,4,5-triarylimidazole dimers may contain a substituent.

Examples of the radical generator include, but are not limited to, products such as Irgacure 184, Irgacure 369, Irgacure 651, Irgacure 500, Irgacure 819, Irgacure 907, Irgacure 784, Irgacure 2959, Irgacure CGI-1700, Irgacure CGI-1750, Irgacure CGI-1850, Irgacure CG24-61, Darocure 1116, Darocure 1173, Lucirin TPO, Lucirin LR 8893, and Lucirin LR 8970 commercially available from BASF and Uvecryl P36 commercially available from UCB.

The blending ratio of the component (F) in the photocurable composition 103 is preferably 0.01% to 10% by weight and more preferably 0.1% to 7% by weight with respect to the amount of the component (E).

When the blending ratio of the component (F) in the photocurable composition 103 is 0.01% by weight or more with respect to the amount of the component (E), the curing rate of the photocurable composition 103 is high, thereby enabling reaction efficiency to be increased. When the blending ratio of the component (F) in the photocurable composition 103 is 10.0% by weight or less with respect to the amount of the component (E), the reduction in strength of an obtained cured film (109, 110) is prevented in many cases.

Another added component (G)

The photocurable composition 103 may further contain an added component (G) in addition to the component (E) and the component (F) depending on various purposes unless effects of the present invention are impaired. Examples of the added component (G) include sensitizers, hydrogen donors, internal mold release agents, surfactants, oxidation inhibitors, volatile solvents, polymer components, and polymerization initiators other than the component (F).

The sensitizers are compounds that are used for the purpose of promoting a polymerization reaction or increasing reaction conversion. The sensitizers are, for example, sensitizing dyes.

The sensitizing dyes are compounds that absorb light with a specific wavelength to be excited and interact with the component (F). The term "interaction" as used herein refers to the transfer of energy or electrons from an excited sensitizing dye to the component (F).

Examples of the sensitizing dyes include, but are not limited to, anthracene derivatives, anthraquinone derivatives, pyrene derivatives, perylene derivatives, carbazole derivatives, benzophenone derivatives, thioxanthone derivatives, xanthone derivatives, coumarin derivatives, phenothiazine derivatives, camphorquinone derivatives, acridine dyes, thiopyrylium dyes, merocyanine dyes, quinoline dyes, styrylquinoline dyes, ketocoumarin dyes, thioxantene dyes, xantene dyes, oxonol dyes, cyanine dyes, rhodamine dyes, and pyrylium dyes.

The sensitizing dyes may be used alone or in combination.

The hydrogen donors are compounds that react with initiation radicals generated from the component (F) or growing end radicals produced during polymerization to generate more active radicals. When the component (F) is a photoradical generator, a hydrogen donor is preferably used.

Examples of the hydrogen donors include, but are not limited to, amine compounds such as n-butylamine, di-n-butylamine, tri-n-butylphosphine, allylthiourea, s-benzylisothiouronium-p-toluenesulfinate, triethylamine, diethylaminoethyl acrylate, triethylenetetramine, 4,4'-bis(dialkylamino)benzophenone, N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethanolamine and N-phenylglycine and mercapto compounds such as 2-mercapto-N-phenylbenzoimidazole and mercaptopropionic acid esters.

The hydrogen donors may be used alone or in combination.

The hydrogen donors may function as sensitizers.

When the photocurable composition 103 contains a sensitizer or hydrogen donor as the added component (G), the amount of the sensitizer or hydrogen donor contained in the photocurable composition 103 is preferably 0.1% to 20% by weight, more preferably 0.1% to 5.0% by weight, and further more preferably 0.2% to 2.0% by weight of the amount of the component (E). When the amount of the sensitizer contained therein is 0.1% by weight or more of the component (E), the effect of promoting polymerization can be effectively exhibited. When the amount of the sensitizer or hydrogen donor contained therein is 5% by weight or less of the amount of the component (E), the molecular weight of a polymeric compound forming a prepared cured film can be sufficiently increased. Furthermore, the incomplete dissolution of the sensitizer or hydrogen donor in the photocurable composition 103 or the reduction in storage stability of the photocurable composition 103 can be suppressed.

An internal mold release agent may be added to the photocurable composition 103 for the purpose of reducing the interfacial bonding strength between the photocured product 109, which is obtained by curing the photocurable composition 103, and a mold 104, that is, for the purpose of reducing demolding force in a demolding step below. The term "internal" as used herein means that an agent is added to the photocurable composition 103 prior to the step of placing the photocurable composition 103. The internal mold release agent may be used alone or in combination with another internal mold release agent.

Examples of the internal mold release agent include surfactants such as silicone surfactants, fluorinated surfactants, and hydrocarbon surfactants. In this embodiment, the internal mold release agent is not polymerizable.

Examples of the fluorinated surfactants include polyalkylene oxide adducts (such as polyethylene oxide adducts and polyphenylene oxide adducts) of alcohols containing a perfluoroalkyl group and polyalkylene oxide adducts (such as polyethylene oxide adducts and polyphenylene oxide adducts) of perfluoropolyethers. The fluorinated surfactants may contain a hydroxy group, an alkoxy group, an alkyl group, an amino group, a thiol group, or the like in a portion (for example, a terminus) of a molecular structure.

The fluorinated surfactants may be commercially available products. Examples of the commercially available products include, but are not limited to, products such as MEGAFACE F-444, MEGAFACE TF-2066, MEGAFACE TF-2067, and MEGAFACE TF-2068 available from DIC Corporation; products such as FLUORAD FC-430 and FLUORAD FC-431 available from Sumitomo 3M Limited; SURFLON S-382 available from AGC Seimi Chemical Co., Ltd.; products such as EFTOP EF-122A, EFTOP EF-122B, EFTOP EF-122C, EFTOP EF-121, EFTOP EF-126, EFTOP EF-127, and EFTOP MF-100 available from Tohkem Products Corporation; products such as PF-636, PF-6320, PF-656, and PF-6520 available from OMNOVA Solutions Inc.; products such as UNIDYNE DS-401, UNIDYNE DS-403, and UNIDYNE DS-451 available from Daikin Industries, Ltd.; and products such as Ftergent 250, Ftergent 251, Ftergent 222F, and Ftergent 208G available from NEOS Company Limited.

The internal mold release agent may be a hydrocarbon surfactant.

Examples of the hydrocarbon surfactant include alkyl alcohol-alkylene oxide adducts obtained by adding alkylene oxides containing two to four carbon atoms to alkyl alcohols containing one to 50 carbon atoms.

Examples of the alkyl alcohol-alkylene oxide adducts include methyl alcohol-ethylene oxide adducts, decyl alcohol-ethylene oxide adducts, lauryl alcohol-ethylene oxide adducts, cetyl alcohol-ethylene oxide adducts, stearyl alcohol-ethylene oxide adducts, and stearyl alcohol-ethylene oxide/propylene oxide adducts. An end group of each alkyl alcohol-alkylene oxide adduct is not limited to a hydroxy group capable of being produced by simply adding a polyalkylene oxide to an alkyl alcohol. This hydroxy group may be converted into, for example, a polar functional group such as a carboxy group, an amino group, a pyridyl group, a thiol group, or a silanol group or a hydrophobic functional group such as an alkyl group or an alkoxy group.

The alkyl alcohol-alkylene oxide adducts may be commercially available products. Examples of the commercially available products include, but are not limited to, polyoxyethylene methyl ethers (methyl alcohol-ethylene oxide adducts) such as BLAUNON MP-400, BLAUNON MP-550, and BLAUNON MP-1000 available from Aoki Oil Industrial Co., Ltd.; polyoxyethylene decyl ethers (decyl alcohol-ethylene oxide adducts) such as FINESURF D-1303, FINESURF D-1305, FINESURF D-1307, and FINESURF D-1310 available from Aoki Oil Industrial Co., Ltd.; polyoxyethylene lauryl ethers (lauryl alcohol-ethylene oxide adducts) such as BLAUNON EL-1505 available from Aoki Oil Industrial Co., Ltd.; polyoxyethylene cetyl ethers (cetyl alcohol-ethylene oxide adducts) such as BLAUNON CH-305 and BLAUNON CH-310 available from Aoki Oil Industrial Co., Ltd.; polyoxyethylene stearyl ethers (stearyl alcohol-ethylene oxide adducts) such as BLAUNON SR-705, BLAUNON SR-707, BLAUNON SR-715, BLAUNON SR-720, BLAUNON SR-730, and BLAUNON SR-750 available from Aoki Oil Industrial Co., Ltd.; random polymer-type polyoxyethylene polyoxypropylene stearyl ethers such as BLAUNON SA-50/50 1000R and BLAUNON SA-30/70 2000R available from Aoki Oil Industrial Co., Ltd.; polyoxyethylene methyl ethers such as Pluriol A760E available from BASF; and polyoxyethylene alkyl ethers such as Emulgen-series surfactants available from Kao Corporation.

Among these surfactants, the internal mold release agent is preferably an alkyl alcohol-alkylene oxide adduct and more preferably a long-chain alkyl alcohol-alkylene oxide adduct.

When the photocurable composition 103 contains the internal mold release agent as the added component (G), the amount of the internal mold release agent contained therein is preferably, for example, 0.001% to 10% by weight, more preferably 0.01% to 7% by weight, and further more preferably 0.05% to 5% by weight of the amount of the component (E). When the amount of the internal mold release agent contained therein is 0.001% to 10% by weight of the amount of the component (E), the effect of reducing demolding force and filling properties are excellent.

The photocurable composition 103 may contain a volatile solvent as the added component (G) and preferably contains substantially no volatile solvent. As used herein, the expression "contain substantially no solvent" means that any volatile solvent other than an unintentionally contained volatile solvent such as an impurity is not contained. That is, the amount of the volatile solvent contained in the photocurable composition 103 is preferably 3% by weight or less and more preferably 1% by weight or less of the amount of the photocurable composition 103. The term "volatile solvent" as used herein refers to a volatile solvent for general use in the photocurable composition 103 or photoresists. The type of the volatile solvent is not particularly limited and the volatile solvent may dissolve and evenly disperse compounds forming the photocurable composition 103 and may be unreactive with the compounds.

Temperature of photocurable composition during blending

In the course of preparing the photocurable composition 103, the component (E) and the component (F) are mixed and dissolved under predetermined temperature conditions, particularly within the range of 0°C to 100°C. This applies to the case where the photocurable composition 103 contains the added component (G).

Viscosity of photocurable composition

A mixture of the components of the photocurable composition 103, the components excluding the volatile solvent, preferably has a viscosity of 1 millipascal-second to 100 millipascal-seconds, more preferably 1 millipascal-second to 50 millipascal-seconds, and further more preferably 1 millipascal-second to 20 millipascal-seconds at 23°C.

When the viscosity of the mixture is 100 millipascal-seconds or less, it does not take a long time to fill the photocurable composition 103 into a recessed portion of a fine pattern on the mold 104 in the course of bringing the photocurable composition 103 and the mold 104 into contact with each other. Furthermore, pattern defects due to filling failures are unlikely to occur.

When the viscosity of the mixture is 1 millipascal-second or more, uneven application is unlikely to occur in the course of applying the photocurable composition 103 to the base member 102 and the photocurable composition 103 is unlikely to leak from an end portion of the mold 104 when the photocurable composition 103 and the mold 104 are brought into contact with each other.

Surface tension of photocurable composition

The mixture of the components of the photocurable composition 103, the components excluding the volatile solvent, preferably has a surface tension of 5 mN/m to 70 mN/m, more preferably 7 mN/m to 35 mN/m, and further more preferably 10 mN/m to 32 mN/m at 23°C. When the surface tension of the mixture is 5 mN/m or more, it does not take a long time to fill the photocurable composition 103 into the recessed portion of the fine pattern on the mold 104 in the course of bringing the photocurable composition 103 and the mold 104 into contact with each other.

When the surface tension of the mixture is 70 mN/m or less, the cured film (109, 110), which is obtained by photocuring the photocurable composition 103, has surface smoothness.

Impurities trapped in photocurable composition

The photocurable composition 103, as well as the adhesion layer-forming composition 100, preferably contains substantially no impurities.

Thus, the photocurable composition 103, as well as the adhesion layer-forming composition 100, is preferably obtained through a purification step. In the purification step, filtration or the like is preferably performed using a filter.

In the case of performing filtration using a filter, a mixture obtained by mixing the component (E), the component (F), and the added component (G), which is added as required, is preferably filtered through a filter with a pore size of, for example, 0.001 μm to 5.0 μm. It is more preferable that filtration is performed using a filter in multiple steps or is repeated using a filter multiple times. A filtrate may be filtered again. A plurality of filters with different pore sizes may be used for filtration. A filter used for filtration is not particularly limited and may be made of a polyethylene resin, a polypropylene resin, a fluorinated resin, a nylon resin, or the like.

Impurities, such as particles, trapped in the photocurable composition 103 can be removed through the purification step. This allows pattern defects due to irregularities to be prevented from being carelessly caused in the photocured product 109, which is obtained by photocuring the photocurable composition 103.

In the case of using the photocurable composition 103 to manufacture a circuit board for use in semiconductor devices such as semiconductor integrated circuits, the trapping of impurities (metal impurities) containing metal atoms in the photocurable composition 103 is preferably avoided if possible. This is because the impurities, as well as the impurities trapped in the adhesion layer-forming composition 100, are prevented from inhibiting the operation of the circuit board. In this case, the concentration of metal impurities in the photocurable composition 103 is preferably 10 ppm or less and more preferably 100 ppb or less.

Thus, the photocurable composition 103 is preferably prepared without being in contact with metal in preparation steps thereof. That is, in the case where raw materials of the component (E), the component (F), and the added component (G) are weighed, are formulated, and are mixed together, no metal weighing tool or container is preferably used. Furthermore, in the above purification step, filtration is preferably performed using a metal impurity-removing filter. The metal impurity-removing filter is not particularly limited and may be a filter made of cellulose, diatomaceous earth, an ion-exchange resin, or the like. The metal impurity-removing filter is preferably used after being cleaned. A cleaning method is preferably as follows: washing with ultra-pure water, washing with alcohol, and co-washing with the photocurable composition 103 are performed in that order.

Method of manufacturing cured product pattern

A method of manufacturing a cured product pattern 111 (cured film having a pattern shape) according to an embodiment of the present invention is described below. Figs. 1A to 1H are schematic sectional views showing an example of the method of manufacturing the cured product pattern 111.

The method of manufacturing the cured product pattern 111 includes:
(1) a first step (adhesion layer-forming step) of forming the adhesion layer 101 on the base member 102 using the adhesion layer-forming composition 100,
(2) a second step (placement step) of placing the photocurable composition 103 on the adhesion layer 101,
(3) a third step (mold-contacting step) of bringing the mold 104 and the photocurable composition 103 placed on the adhesion layer 101 into contact with each other,
(5) a fourth step (light irradiation step) of irradiating the photocurable composition 103 with light in such a state that the photocurable composition 103 is in contact with the mold 104, and
(6) a fifth step (demolding step) of separating the mold 104 from a cured product obtained in the fourth step.

The method of manufacturing the cured product pattern 111 may further include the following step between the third and fourth steps: (4) a step (alignment step) of aligning the base member 102 with the mold 104.

The method of manufacturing the cured product pattern 111 is one using a photonanoimprinting technique.

The cured product pattern 111, which is obtained by the method, is preferably a film having a pattern with a size of 1 nm to 10 mm and more preferably 10 nm to 100 μm. Incidentally, a pattern-forming technique for preparing a film having a pattern (irregular structure) with a nano-size (1 nm to 100 nm) is generally referred to as the photonanoimprinting technique.

Each step is described below.

(1) Adhesion layer-forming step

In this step (adhesion layer-forming step), the adhesion layer 101 is formed on the base member 102 using the adhesion layer-forming composition 100 as shown in Fig. 1A. The adhesion layer 101 mainly contains a polymeric compound (polymer).

The base member 102, which is a target on which the photocurable composition 103 is placed, is a substrate or a support and can be selected from arbitrary base members depending on various purposes. The base member 102 may be, for example, a silicon wafer; a semiconductor device substrate made of aluminium, a titanium-tungsten alloy, an aluminium-silicon alloy, an aluminium-copper-silicon alloy, silicon oxide, silicon nitride, or the like; a quartz substrate; a glass substrate; an optical film; a ceramic film; a vapor-deposited film; a magnetic film; a reflective film; a metal base member made of Ni, Cu, Cr, Fe, or the like; a paper sheet; a polymer base member such as a polyester film, a polycarbonate film, or a polyimide film; a TFT array base member; an electrode plate for PDPs; a plastic base member; a conductive base member made of ITO or metal; an insulating base member; or the like. In the case where the base member 102 is processed by etching or the like in a base member-processing step below, the base member 102 is preferably the silicon wafer or the semiconductor device substrate. The base member 102 may be one obtained by depositing a single type or multiple types of films on the semiconductor device substrate using spin-on-glass, an organic material, metal, an oxide, a nitride, or the like.

In this embodiment, the base member 102 preferably has hydroxy groups (OH groups) such as silanol groups (SiOH groups) on the surface thereof. This type of base member is, for example, a silicon wafer, a quartz wafer, a glass wafer, or the like. When the base member 102 has the hydroxy groups on the surface thereof, the hydroxy groups, which are present on the surface of the base member 102, probably readily form chemical bonds with the thiol groups of the compound (B) by heat treatment in a basic step. When the compound (A) contains the alkoxyalkyl groups, the hydroxy groups probably form chemical bonds with the alkoxyalkyl groups of the compound (A).

For example, the following processes can be used to apply the adhesion layer-forming composition 100 to the base member 102: an inkjet process, a dip-coating process, an air knife-coating process, a curtain-coating process, a wire bar-coating process, a gravure-coating process, an extrusion-coating process, a spin coating process, a slit-scanning process, and the like. Among these processes, the spin coating process is particularly preferable from the viewpoint of application properties, particularly thickness evenness.

After the adhesion layer-forming composition 100 is applied to the base member 102, the solvent (C) contained in the adhesion layer-forming composition 100 is evaporated by drying. In this operation, it is preferable that the base member 102 is allowed to react with the compound (A) or (B) and the compounds (A) and (B) are allowed to react with each other together with the evaporation of the solvent (C). This forms a bond between the base member 102 and the adhesion layer 101 and a bond between the compounds (A) and (B) in the adhesion layer 101. The bond between the compounds (A) and (B) is estimated to be a sulfide bond formed by the following reaction: a dealcoholization reaction between an alkoxyalkyl group contained in the compound (A) and a thiol group contained in the compound (B) or a dehydration reaction between an alkylol group contained in the compound (A) and the thiol group contained in the compound (B).

During these reactions, heating is preferably performed. The temperature during these reactions can be appropriately selected depending on the reactivity between the base member 102 and the compound (A) or (B); the reactivity between the compounds (A) and (B); the boiling point of the compound (A), the compound (B), or the solvent (C); or the like. The temperature during these reactions is preferably 70°C to 250°C, more preferably 100°C to 220°C, and further more preferably 140°C to 220°C. The drying of the solvent (C), the reaction of the base member 102 with the compound (A) or (B), and a crosslinking reaction between the compounds (A) and (B) may be carried out at the same temperature or different temperatures. That is, these reactions may be carried out at the same time or in a sequential manner.

The thickness of the adhesion layer 101, which is formed by placing the adhesion layer-forming composition 100 on the base member 102, depends on applications. The thickness of the adhesion layer 101 is preferably, for example, 0.1 nm to 100 nm, more preferably 0.5 nm to 60 nm, and further more preferably 1 nm to 10 nm.

In the case where the adhesion layer 101 is formed by applying the adhesion layer-forming composition 100 to the base member 102, another adhesion layer may be formed on the formed adhesion layer 101 by multiple application using the adhesion layer-forming composition 100. The surface of the adhesion layer 101 is preferably as flat as possible. The adhesion layer 101 preferably has a surface roughness of 1 nm or less.

Through the above step, a stack including the base member 102 and a polymer layer (the adhesion layer 101) deposited on the base member 102 can be formed. The adhesion layer 101 contains the sulfide bond formed by the reaction between the alkoxyalkyl or alkylol group contained in the compound (A) and the thiol group contained in the compound (B) as described above.

(2) Placement step

In this step (placement step), the photocurable composition 103 is placed on (applied to) the adhesion layer 101 formed on the base member 102 as shown in Fig. 1B, whereby a wet coating is formed.

In this embodiment, for example, the following processes can be used to place the photocurable composition 103 on the adhesion layer 101: an inkjet process, a dip-coating process, an air knife-coating process, a curtain-coating process, a wire bar-coating process, a gravure-coating process, an extrusion-coating process, a spin coating process, a slit-scanning process, and the like. Among these processes, the inkjet process is particularly preferable in the photonanoimprinting technique. The thickness of the wet coating (shape transfer layer) depends on applications and is, for example, 0.01 μm to 100.0 μm.

(3) Mold-contacting step

Next, as shown in Fig. 1C, the mold 104, which has an original pattern for transferring a pattern shape, is brought into contact with the wet coating, which is formed in the preceding step (placement step) and is made of the photocurable composition 103 (Fig. 1C-1). This allows (a portion of) the wet coating, which is made of the photocurable composition 103, to be filled in a recessed portion of a fine pattern on a surface of the mold 104, whereby a coating film 105 is formed so as to be filled in the fine pattern (Fig. 1C-2).

The mold 104 is preferably made of a light-transmissive material in consideration of a subsequent step (light irradiation step). A material for forming the mold 104 is preferably glass, quartz, a transparent resin such as PMMA or polycarbonate, a transparent metal-deposited film, a flexible film made of polydimethylsiloxane, a photocured film, a metal film, or the like. In the case where the transparent resin is used to form the mold 104, the transparent resin needs to be insoluble in a component contained in the photocurable composition 103. Quartz has a small thermal expansion coefficient and little pattern distortion and therefore is particularly preferably used to form the mold 104.

The fine pattern on the surface of the mold 104 preferably has a height of 4 nm to 200 nm and an aspect ratio of 1 to 10.

The mold 104 may be surface-treated before this step, that is, the mold-contacting step of bringing the photocurable composition 103 and the mold 104 into contact with each other, for the purpose of increasing the releasability of the mold 104 from the photocurable composition 103. An example of a method of surface-treating the mold 104 is a method in which a layer of a release agent is formed by applying the release agent to a surface of the mold 104.

Examples of the release agent, which is applied to a surface of the mold 104, include silicone release agents, fluorinated release agents, hydrocarbon release agents, polyethylene release agents, polypropylene release agents, paraffin release agents, montan release agents, and carnauba release agents. For example, an application-type release agent such as OPTOOL DSX commercially available from Daikin Industries, Ltd. can be preferably used. These release agents may be used alone or in combination. Among these release agents, the fluorinated and hydrocarbon release agents are particularly preferable.

In this step (mold-contacting step), when the mold 104 and the photocurable composition 103 are brought into contact with each other as shown in Fig. 1C-1, the pressure (mold pressure) applied to the photocurable composition 103 is not particularly limited. The pressure applied to the photocurable composition 103 is usually 0 MPa to 100 MPa. In particular, the pressure applied to the photocurable composition 103 is preferably 0 MPa to 50 MPa, more preferably 0 MPa to 30 MPa, and further more preferably 0 MPa to 20 MPa.

In this step, the contact time of the mold 104 with the photocurable composition 103 is not particularly limited and is usually 0.1 seconds to 600 seconds. The contact time of the mold 104 with the photocurable composition 103 is preferably 0.1 seconds to 300 seconds, more preferably 0.1 seconds to 180 seconds, and further more preferably 0.1 seconds to 120 seconds.

This step can be performed under either of an air atmosphere, a reduced pressure atmosphere, and an inert gas atmosphere. The reduced pressure atmosphere and the inert gas atmosphere are preferable because the influence of oxygen or moisture on a curing reaction can be prevented. Examples of an inert gas capable of being used in the case of performing this step in the inert gas atmosphere include nitrogen, carbon dioxide, helium, argon, chlorofluorocarbon gases, and mixtures of these gases. In the case of performing this step in a specific gas atmosphere including the air atmosphere, the pressure therein is preferably 0.0001 atmospheres to 10 atmospheres.

The mold-contacting step may be performed under an atmosphere (hereinafter referred to as "condensable gas atmosphere") containing a condensable gas. The term "condensable gas" as used herein refers to gas that is condensed and liquefied by the capillary force created by the pressure during filling. In particular, the condensable gas is condensed and liquefied when gases in the condensable gas atmosphere are filled in the recessed portion of the fine pattern formed on the mold 104 and a space between the mold 104 and the base member 102 or the adhesion layer 101 together with (a portion of) the coating film 105. Before the photocurable composition 103 (shape transfer layer) and the mold 104 are brought into contact with each other in the mold-contacting step (Fig. 1C-1), the condensable gas is present in the condensable gas atmosphere in the form of gas.

Performing the mold-contacting step in the condensable gas atmosphere liquefies the condensable gas in the recessed portion of the fine pattern to eliminate bubbles and therefore is excellent in filling properties. The condensable gas may be dissolved in the photocurable composition 103.

The boiling point of the condensable gas is not particularly limited and may be lower than or equal to the temperature of an atmosphere used in the mold-contacting step. The boiling point of the condensable gas is preferably -10°C to 23°C and more preferably 10°C to 23°C. When the boiling point of the condensable gas is within this range, filling properties are excellent.

The vapor pressure of the condensable gas at the temperature of the atmosphere used in the mold-contacting step is not particularly limited and may be lower than or equal to the molding pressure during pressing in the mold-contacting step. The vapor pressure of the condensable gas at the atmosphere temperature is preferably 0.1 MPa to 0.4 MPa. When the vapor pressure of the condensable gas at the atmosphere temperature is within this range, filling properties are excellent. When the vapor pressure of the condensable gas at the atmosphere temperature is higher than 0.4 MPa, the effect of eliminating bubbles cannot be sufficiently achieved in some cases. However, when the vapor pressure of the condensable gas at the atmosphere temperature is lower than 0.1 MPa, decompression is necessary. The configuration of an imprinting device for manufacturing a film with a pattern shape by the manufacturing method according to this embodiment tends to be complicated.

The atmosphere temperature in the mold-contacting step is not particularly limited and is preferably 20°C to 25°C.

Examples of the condensable gas include, but are not limited to, chlorofluorocarbons (CFCs) such as trichlorofluoromethane, fluorocarbons (FCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs) such as 1,1,1,3,3-pentafluoropropane (CHF₂CH₂CF₃, HFC-245fa, PFP), and hydrofluoroethers (HFEs) such as pentafluoroethyl methyl ether (CF₃CF₂OCH₃, HFE-245mc).

Among these compounds, 1,1,1,3,3-pentafluoropropane (a vapor pressure of 0.14 MPa at 23°C and a boiling point of 15°C), trichlorofluoromethane (a vapor pressure of 0.1056 MPa at 23°C and a boiling point of 24°C), and pentafluoroethyl methyl ether are preferable from the viewpoint that filling properties are excellent when the atmosphere temperature in the mold-contacting step is 20°C to 25°C. Furthermore, 1,1,1,3,3-pentafluoropropane is particularly preferable from the viewpoint of excellent safety.

The condensable gas may be used alone or in combination with another condensable gas. Alternatively, a gas mixture prepared by mixing the condensable gas with a non-condensable gas such as air, nitrogen, carbon dioxide, helium, or argon may be used. The non-condensable gas, which is mixed with the condensable gas, is preferably helium from the viewpoint of filling properties. Helium can pass through the mold 104. Therefore, when gases (the condensable gas and helium) in the atmosphere are filled in the recessed portion of the fine pattern formed on the mold 104 together with (a portion of) the coating film 105 in the mold-contacting step, the condensable gas is liquefied and helium passes through the mold 104. Thus, using helium as a non-condensable gas is excellent in filling properties.

(4) Alignment step

Next, as shown in Fig. 1D, the position of the mold 104 and/or the position of the base member 102 is adjusted as required such that mold-side positioning marks 106 are aligned with positioning marks 107 of the base member 102.

(5) Light irradiation step

Next, as shown in Fig. 1E, a portion of the photocurable composition 103 that is in contact with the mold 104 is irradiated with light through the mold 104 in such a state that the mold-side positioning marks 106 are aligned with positioning marks 107 in Step (4) (the alignment step). In particular, the coating film 105 filled in the fine pattern of the mold 104 is irradiated with light through the mold 104 (Fig. 1E-1). This allows the coating film 105 filled in the fine pattern of the mold 104 to be cured with applied light 108, thereby forming the photocured product 109 (Fig. 1E-2).

Herein, light applied to the photocurable composition 103, which forms the coating film 105 filled in the fine pattern of the mold 104, is selected depending on the sensitivity wavelength of the photocurable composition 103. In particular, ultraviolet light with a wavelength of 150 nm to 400 nm, an X-ray, an electron beam, or the like is appropriately selected and is preferably used.

Light (the applied light 108) applied to the photocurable composition 103 is preferably ultraviolet light. This is because most of commercially available curing aids (photopolymerization initiators) have sensitivity to ultraviolet light. Examples of a light source emitting ultraviolet light include high-pressure mercury lamps, ultra-high-pressure mercury lamps, low-pressure mercury lamps, deep-UV lamps, carbon-arc lamps, chemical lamps, metal halide lamps, xenon lamps, KrF excimer lasers, ArF excimer lasers, and F₂ excimer lasers. An ultra-high-pressure mercury lamp is preferably used. The number of light sources used may be 1 or more. Light may be applied to the whole or a portion of the coating film 105 filled in the fine pattern of the mold 104.

Light may be intermittently applied to all regions on the base member 102 multiple times or may be continuously applied to the all regions. Alternatively, light may be applied to a region A in a first irradiation course and may be applied to a region B different from the region A in a second irradiation course.

In this embodiment, the light exposure of the photocurable composition 103 in this step is preferably 90 mJ/cm² or less and more preferably 30 mJ/cm² or less.

(6) Demolding step

Next, the photocured product 109 and the mold 104 are separated from each other. At this point in time, the base member 102 is overlaid with a cured film 110 having a predetermined pattern shape.

In this step (demolding step), the photocured product 109 and the mold 104 are separated from each other as shown in Fig. 1F, whereby the cured film 110 is obtained. In Step (5) (light irradiation step), the cured film 110 is formed so as to have a pattern shape that is the inverse of the fine pattern formed on the mold 104.

In the case of performing the mold-contacting step in the condensable gas atmosphere, the condensable gas evaporates because the pressure at the interface between the photocured product 109 and the mold 104 reduces when the photocured product 109 and the mold 104 are separated from each other in the demolding step. This tends to have the effect of reducing the demolding force needed to separate the photocured product 109 and the mold 104 from each other.

A method of separating the photocured product 109 and the mold 104 from each other is not particularly limited and may cause no physical damage to a portion of the photocured product 109 when the photocured product 109 and the mold 104 are separated from each other. Conditions for separating the photocured product 109 and the mold 104 from each other are not particularly limited. For example, the mold 104 may be separated from the photocured product 109 in such a manner that the base member 102 is fixed and the mold 104 is moved away from the base member 102. Alternatively, the photocured product 109 may be separated from the mold 104 in such a manner that the mold 104 is fixed and the base member 102 is moved away from the mold 104. The photocured product 109 and the mold 104 may be separated from each other in such a manner that the base member 102 and the mold 104 are pulled in opposite directions.

Through a series of steps including Steps (1) to (6) (manufacturing process), a cured film having a desired irregular pattern shape (a pattern shape following the irregular shape of the mold 104) in a desired position can be obtained. The obtained cured film can be used as, for example, an optical member such as a Fresnel lens or a diffraction grating (including use as a portion of the optical member). In this case, an optical member including the base member 102 and the cured film 110 placed thereon can be obtained.

In the method of manufacturing the cured product pattern 111, a repeating unit (shot) composed of Steps (1) to (6) may be repeatedly performed on the base member 102 multiple times. Repeating the repeating unit (shot) composed of Steps (1) to (6) multiple times allows the cured film 110 to have a plurality of desired irregular pattern shapes (pattern shapes following the irregular shape of the mold 104) in desired positions on the base member 102.

(7) Residual film-removing step of partly removing cured film

The cured film 110 obtained in Step (6) (demolding step) has a specific pattern shape. A portion of the cured film 110 may possibly remain on a region other than a region of the cured film 110 that has the pattern shape (such a portion of the cured film 110 is hereinafter referred to as "residual film" in some cases). In this case, the residual film located in a region of the cured film 110 that should be removed and the adhesion layer 101, which underlies the residual film, are removed as shown in Fig. 1G. This allows the cured product pattern 111 to be obtained. The cured product pattern 111 has a desired irregular pattern shape (a pattern shape following the irregular shape of the mold 104).

An example of a method of removing the residual film and the adhesion layer 101, which underlies the residual film, is a method in which the residual film, which is a recessed portion of the cured film 110, is removed by a process such as etching. This allows a surface of the base member 102 to be exposed from a recessed portion of the cured film 110.

In the case of removing the residual film, which is in the recessed portion of the cured film 110, and the adhesion layer 101, which underlies the residual film, by etching, a method of removing the residual film and the adhesion layer 101 is not particularly limited. For example, dry etching can be used. A known dry etching system can be used for dry etching. A source gas for dry etching is appropriately selected depending on the composition of the cured film 110 to be etched. The following gases can be used: halogen-containing gases such as CF₄, C₂F₆, C₃F₈, CCl₂F₂, CCl₄, CBrF₃, BCl₃, PCl₃, SF₆, and Cl₂; gases, such as O₂, CO, and CO₂, containing an oxygen atom; inert gases such as He, N₂, and Ar; H₂; and NH₃. These gases can be used in combination.

By a manufacturing process including Steps (1) to (7), the cured product pattern 111, which has a desired irregular pattern shape (a pattern shape following the irregular shape of the mold 104) in a desired position, can be obtained and an article including the cured product pattern 111 can be also obtained. That is, the following component can be obtained: a device component including the base member 102; the adhesion layer 101, which is placed on the base member 102; and a photocured product (the cured product pattern 111) which is placed on the adhesion layer 101 and which has an irregular pattern.

In the device component, which is obtained in this embodiment, the adhesion layer 101 has a crosslinked structure formed from the compounds (A) and (B). When the compound (A) used is the compound represented by Formula (1), the adhesion layer 101 contains a sulfide bond and a 1,3,5-triazine ring in which the 2-, 4-, and 6-positions are substituted with nitrogen atoms in its structure. That is, the device component includes a base member, a photocured product which overlies the base member and which has an irregular pattern, and an organic layer placed between the base member and the photocured product. The organic layer contains a 1,3,5-triazine ring and a sulfide bond.

In the case of processing the base member 102 using the cured product pattern 111, the base member-processing step (Step (8)) is performed as described below.

An optical component can be obtained using the cured product pattern 111 as an optical member such as a diffraction grating or a polarizer (including use as a portion of the optical member). This allows the optical component to include the base member 102 and the cured product pattern 111, which is placed on the base member 102.

(8) Base member-processing step

The cured product pattern 111, which has the irregular pattern, can be used as, for example, an interlayer insulating film for use in electronic components such as semiconductor elements. Furthermore, the cured product pattern 111 can be used as a resist film for semiconductor element fabrication. The term "semiconductor element" as used herein includes, but is not limited to, for example, LSIs, system LSIs, DRAMs, SDRAMs, RDRAMs, and D-RDRAMs.

In the case of using the cured product pattern 111 as a resist film, a portion (a region represented by reference numeral 112 in Fig. 1G) of the base member 102 that is exposed in Step (7) (residual film-removing step) is subjected to etching, ion implantation, or the like. In this operation, the cured product pattern 111 functions as an etching mask. In addition, an electronic member is formed, whereby a circuit structure 113 (Fig. 1H) based on the pattern shape of the cured product pattern 111 can be formed on the base member 102. This enables a circuit board for use in semiconductor elements and the like to be manufactured. Furthermore, an electronic device such as a display, a camera, or a medical device can be manufactured by connecting the circuit board to a circuit control system or the like.

Likewise, a device component such as an optical component, a microfluidic channel structure, or a structure for patterned media can be obtained in such a manner that etching, ion implantation, or the like is performed using the cured product pattern 111 as a resist film.

Furthermore, an optical component can be obtained in such a manner that etching, ion implantation, or the like is performed using the cured product pattern 111 as a mask (resist film).

Alternatively, an imprinting mold can be manufactured in such a manner that a quartz substrate corresponding to the base member 102 is etched using the cured product pattern 111. In this case, the quartz substrate, which corresponds to the base member 102, may be directly etched using the cured product pattern 111 as a mask. The quartz substrate may be etched in such a manner that a hardmask material layer is etched using the cured product pattern 111 as a mask and a pattern, made of a hardmask material, transferred from the etched hardmask material layer is used as a mask. Alternatively, the quartz substrate may be etched in such a manner that a second cured product is formed in a recessed portion of the cured product pattern 111 using a second curable material and is used as a mask.

In the case where an exposed surface portion of a substrate is etched using the cured product pattern 111 as a mask, dry etching can be used. A known dry etching system can be used for dry etching. A source gas for dry etching is appropriately selected depending on the composition of a cured film to be etched. The following gases can be used: halogen-containing gases such as CF₄, CHF₃, C₂F₆, C₃F₈, C₄F₈, CCl₂F₂, CCl₄, CBrF₃, BCl₃, PCl₃, SF₆, and Cl₂; gases, such as O₂, CO, and CO₂, containing an oxygen atom; inert gases such as He, N₂, and Ar; H₂; and NH₃. Fluorine-containing gases such as CF₄, CHF₃, C₂F₆, C₃F₈, C₄F₈, CCl₂F₂, CBrF₃, and SF₆ are preferable. This is because the photocurable composition 103 has high resistance to dry etching using the fluorine-containing gases. These gases can be used in combination.

Etching and ion implantation have been described as a method of processing the base member 102 using the cured product pattern 111 as a mask. The method of processing the base member 102 using the cured product pattern 111 as a mask is not limited to etching or ion implantation. For example, the base member 102 may be plated in such a state that the cured product pattern 111 is placed on the base member 102.

In the case of manufacturing a circuit board or an electronic component, the cured product pattern 111 may be finally removed from the processed base member 102. The cured product pattern 111 may remain in the form of a member for forming an element.

The present invention is further described below in detail with reference to examples. The technical scope of the present invention is not limited to the examples. Incidentally, "parts" and "%" below are on a weight basis unless otherwise specified.

(1) Evaluation of curability

Adhesion layer-forming compositions were evaluated for curability by a method below.

(1-1) Preparation of adhesion layer-forming compositions

A compound (A) and a compound (B) were blended at a weight ratio shown in Table 1 and were dissolved in a volatile solvent (C) which was polypropylene glycol monomethyl ether acetate available from Tokyo Chemical Industry Co., Ltd., whereby a mixed solution in which the total concentration of the compounds (A) and (B) was 5% was obtained.

Next, the obtained mixed solution was filtered through a polytetrafluoroethylene filter with a pore size of 0.2 μm. In this way, adhesion layer-forming compositions for the evaluation of curability, that is, compositions 1 to 11 were prepared.

(Compound (A))
(A-1) Compound containing six methoxymethyl groups: hexamethoxymethylmelamine, represented by Formula (a), available from Sanwa Chemical Co., Ltd. under the trade name NIKALAC MW-390.

(A-2) Compound containing four methoxymethyl groups (for comparison): 1,3,4,6-tetrakis(methoxymethyl)glycoluril, represented by Formula (b), available from Sanwa Chemical Co., Ltd. under the trade name NIKALAC MX-270.

(Compound (B))
(B-1) 1,3,5-Tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, represented by Formula (c), available from Showa Denko K.K. under the trade name Karenz MT NR-1.

(B-2) Trimethylolpropane tris(3-mercaptopropionate), represented by Formula (d), available from Tokyo Chemical Industry Co., Ltd.

(B-3) Pentaerythritol tetrakis(3-mercaptobutyrate), represented by Formula (e), available from Showa Denko K.K. under the trade name Karenz MT PE-1.

(B-4) Pentaerythritol tetrakis(3-mercaptopropionate), represented by Formula (f), available from Tokyo Chemical Industry Co., Ltd.

(1-2) Formation of adhesion layers

Each of the prepared compositions 1 to 11 was applied to a silicon wafer by spin coating at 3,000 rpm for 30 seconds. Thereafter, each of the prepared compositions 1 to 11 was heated on a hotplate, whereby an adhesion layer was formed. Heating conditions are shown in Table 2.

(1-3) Evaluation of curability

The adhesion layer, which was formed in (1-2), was evaluated for curability in such a manner that a surface of the adhesion layer was wiped with BEMCOT impregnated with acetone and the dissolution and peeling of the adhesion layer were visually checked. In this evaluation, an adhesion layer not dissolved or peeled off was rated A and an adhesion layer partly dissolved or peeled off was rated B. Evaluation results are summarized in The 2.

The compositions 1 to 7 are those in which the compound (A) used is A-1. The compositions 1 to 7 have excellent curability (Examples 1 to 7).

The compositions 8 to 11 are those in which the compound (A) used is A-2. The compositions 8 to 11 have insufficient curability (Comparative Examples 1 to 4).

A-1 contains six methoxymethyl groups which are functional groups capable of being bonded to thiol groups contained in the compound (B). Therefore, A-1 has probably high reactivity with the compound (B) and a network structure formed by crosslinking A-1 and the compound (B) in an adhesion layer formed after a reaction is probably dense. As a result, the compositions 1 to 7 have excellent curability.

On the other hand, A-2 contains four methoxymethyl groups which are functional groups capable of being bonded to the thiol groups contained in the compound (B). That is, the number of the methoxymethyl groups contained in A-2 is less than the number of the methoxymethyl groups contained in A-1. Therefore, A-2 probably has insufficient reactivity with the compound (B). Furthermore, a network structure formed by crosslinking A-2 and the compound (B) in an adhesion layer formed after a reaction is probably sparser than the network structure formed by crosslinking A-1 and the compound (B). As a result, the compositions 8 to 11 have insufficient curability.

A-2 contains a carbonyl group in its molecular structure. Since an oxygen atom in the carbonyl group has electron withdrawing ability, the methoxymethyl groups contained in A-2 are less reactive with the thiol groups contained in the compound (B) as compared to the methoxymethyl groups contained in A-1. This is probably part of the reason that the compositions 8 to 11 have insufficient curability. On the other hand, A-1 contains no carbonyl group in its molecular structure. Therefore, unlike the above, the methoxymethyl groups contained in A-1 are not reduced in reactivity. Hence, it is conceivable that the compositions 1 to 7 have excellent curability.

As described above, the compositions 1 to 7 have sufficient curability. Therefore, the occurrence of pattern peeling defects can probably be suppressed by forming an adhesion layer using each of the compositions 1 to 7.

(2) Evaluation of adhesion

Next, the adhesion between a base member and a cured film obtained by curing each photocurable composition was evaluated by a method below.

(2-1) Preparation of adhesion layer-forming compositions

The compositions 1 to 7, which exhibited sufficient curability in the evaluation of curability as described above, were 10 times diluted with a volatile solvent (C), that is, propylene glycol monomethyl ether acetate available from Tokyo Chemical Industry Co., Ltd., whereby mixed solutions in which the total concentration of the compound (A), the compound (B), and an added component (D) was 0.5% were obtained.

Next, the obtained mixed solutions were filtered through a polytetrafluoroethylene filter with a pore size of 0.2 μm, whereby compositions 1' to 7' for adhesion evaluation were prepared.

(2-2) Preparation of photocurable compositions

A component (E) (polymerizable compound), component (F) (photopolymerization initiator), and added component (G) below were blended together at a weight ratio shown in Table 3, whereby mixed solutions were obtained. Values in Table 3 are on a weight basis.

The obtained mixed solutions were filtered through an ultra-high-molecular weight polyethylene filter with a pore size of 0.2 μm, whereby a photocurable composition a and a photocurable composition b were prepared.

Compound (E): polymerizable compound

(E-1) Isobornyl acrylate available from Kyoeisha Chemical Co., Ltd. under the trade name IB-XA.
(E-2) Benzyl acrylate available from Osaka Organic Chemical Industry Ltd. under the trade name V#160.
(E-3) Neopentyl glycol diacrylate available from Kyoeisha Chemical Co., Ltd. under the trade name NP-A.
(E-4) Dimethyloltricyclodecane diacrylate available from Kyoeisha Chemical Co., Ltd. under the trade name DCP-A.

Compound (F): photopolymerization initiator

(F-1) Lucirin TPO, represented by Formula (g), available from BASF.

Another compound (G)

(G-1) 4,4'-Bis(diethylamino)benzophenone available from Tokyo Chemical Industry Co., Ltd.
(G-2) Polyoxyethylene stearyl ether, represented by Formula (h), available from Kao Corporation under the trade name Emulgen 320P.

(2-3) Formation of adhesion layers

Each of the prepared compositions 1' to 7' was applied to a silicon wafer by spin coating at 3,000 rpm for 30 seconds. Thereafter, each of the prepared compositions 1' to 7' was heated on a hotplate, whereby an adhesion layer was formed. Heating conditions were as follows: 220°C for 30 minutes for the compositions 1' to 3' and 220°C for 3 minutes for the compositions 4' to 7'. The formed adhesion layer had a thickness of 10 nm or less.

(2-4) Curing of photocurable compositions

On the adhesion layer formed on the silicon wafer as described in Item (2-3), 2 μL of the photocurable composition a prepared in Item (2-2) was dropped and placed. A quartz glass plate with a thickness of 1 mm was placed on the resulting photocurable composition a, whereby a 35 mm × 25 mm region was filled with the photocurable composition a.

Next, light emitted from a UV light source equipped with an ultra-high-pressure mercury lamp was filtered through an interference filter below and was then applied to the photocurable composition a for 200 seconds through the quartz glass plate, whereby the photocurable composition a was cured and a cured film was thereby obtained. The interference filter used for light irradiation was VPF-25C-10-15-31300 available from SIGMAKOKI Co., Ltd. The light used was UV light with a single wavelength of 313 ± 5 nm and the irradiance was 1 mW/cm².

The photocurable composition b, as well as the photocurable composition a, was photocured, whereby a cured film was obtained.

(2-5) Evaluation of adhesion

After photocuring, the quartz glass plate was peeled off and whether the cured film was peeled from the silicon wafer was visually checked. In this evaluation, a cured film not at all peeled from the 35 mm × 25 mm region was rated A and a cured film peeled from a portion of the 35 mm × 25 mm region was rated B.

Evaluation results are summarized in Table 4.

Examples 1a to 7a are those in which the adhesion layers were formed using the compositions 1' to 7' and the cured films were formed using the photocurable composition a. Examples 1b to 7b are those in which the adhesion layers were formed using the compositions 1' to 7' and the cured films were formed using the photocurable composition b. Comparative Example 5a and Comparative Example 5b are those in which cured films were formed directly on silicon wafers using the photocurable composition a and the photocurable composition b, respectively, without forming adhesion layers.

No peeling defects occurred in Examples 1a to 7a and 1b to 7b. However, peeling defects occurred in Comparative Examples 5a and 5b, in which no adhesion layers were formed.

That is, using an adhesion layer-forming composition enables an adhesion layer capable of increasing the adhesion between a base member and a cured film to be formed and also enables the occurrence of pattern peeling defects to be suppressed.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

This application claims the benefit of Japanese Patent Application No. 2015-017714, filed January 30, 2015, and Japanese Patent Application No. 2015-221384, filed November 11, 2015, which are hereby incorporated by reference herein in their entirety.

Claims

An adhesion layer-forming composition containing:
a compound (A) containing either or both of alkoxyalkyl and alkylol groups, the number of either of the alkoxyalkyl and alkylol groups per molecule or the number of the alkoxyalkyl and alkylol groups per molecule being at least 5 in total; and
a compound (B) containing at least two thiol groups per molecule.
The adhesion layer-forming composition according to Claim 1, further containing a volatile solvent, wherein the content of the volatile solvent is 70% to 99.9% by mass when the whole of the adhesion layer-forming composition is 100% by mass.
The adhesion layer-forming composition according to Claim 1 or 2, containing no photopolymerization initiator.
The adhesion layer-forming composition according to any one of Claims 1 to 3, wherein the content of particles with a size of greater than 0.2 μm is less than 3% by mass when the whole of the adhesion layer-forming composition is 100% by mass.
The adhesion layer-forming composition according to any one of Claims 1 to 4, wherein the compound (A) is a compound represented by the following formula:

where R₁ to R₆ independently represent a hydrogen atom, an alkyl group, an alkoxyalkyl group, or an alkylol group and at least five of R₁ to R₆ are alkoxyalkyl groups or alkylol groups.
The adhesion layer-forming composition according to any one of Claims 1 to 5, wherein the compound (A) includes at least one selected from the group consisting of pentamethoxymethylmelamine, hexamethoxymethylmelamine, (hydroxymethyl)pentakis(methoxymethyl)melamine, hexaethoxymethylmelamine, hexabutoxymethylmelamine, pentamethylolmelamine, and hexamethylolmelamine.
The adhesion layer-forming composition according any one of Claims 1 to 6, wherein the compound (A) is a compound containing either or both of alkoxyalkyl and alkylol groups, the number of either of the alkoxyalkyl and alkylol groups per molecule or the number of the alkoxyalkyl and alkylol groups per molecule being at least 6 in total.
The adhesion layer-forming composition according to any one of Claims 1 to 7, wherein the compound (B) contains at least three thiol groups per molecule.
The adhesion layer-forming composition according to any one of Claims 1 to 8, wherein the compound (B) is a primary thiol.
The adhesion layer-forming composition according to any one of Claims 1 to 9, wherein the proportion α/β is 0.25 to 4, where α (%) is the weight fraction of the compound (A) and β (%) is the weight fraction of the compound (B) when the whole of the adhesion layer-forming composition is 100% by weight.
The adhesion layer-forming composition according to any one of Claims 1 to 10, wherein the sum of α and β is 0.1 to 10, where α (%) is the weight fraction of the compound (A) and β (%) is the weight fraction of the compound (B) when the whole of the adhesion layer-forming composition is 100% by weight.
The adhesion layer-forming composition according to any one of Claims 1 to 11, being for photonanoimprinting.
A method of manufacturing a cured product pattern, comprising:
a first step of placing the adhesion layer-forming composition according to any one of Claims 1 to 12 on a base member to form an adhesion layer;
a second step of placing a photocurable composition on the adhesion layer;
a third step of bringing the photocurable composition and a mold having an original pattern used to transfer a pattern shape into contact with each other;
a fourth step of irradiating the photocurable composition with light to produce a cured product; and
a fifth step of separating the cured product and the mold from each other.
The method according to Claim 13, wherein the photocurable composition contains a compound containing an acryloyl group or a methacryloyl group.
The method according to Claim 13 or 14, wherein the base member has hydroxy groups on the surface thereof.
A method of manufacturing an optical component, comprising a step of obtaining a cured product pattern by the method according to any one of Claims 13 to 15.
A method of manufacturing a circuit board, comprising:
a step of obtaining a cured product pattern by the method according to any one of Claims 13 to 15; and
a step of etching or ion-implanting the base member using the obtained cured product pattern as a mask.
The method according to Claim 17, wherein the circuit board is a circuit board for use in semiconductor elements.
A method of manufacturing an imprinting mold, comprising:
a step of obtaining a cured product pattern on the base member by the method according to any one of Claims 13 to 15; and
a step of etching the base member using the obtained cured product pattern as a mask.
A device component comprising:
a base member;
a cured product which overlies the base member and which has an irregular pattern; and
an organic layer placed between the base member and the cured product,
wherein the organic layer contains a 1,3,5-triazine ring and a sulfide bond.