Curable composition, film forming method, and manufacturing method

Abstract

The invention provides a curable composition, a film forming method and a manufacturing method. A curable composition containing a polymerizable compound, a photopolymerization initiator, and a solvent, in which the viscosity of the curable composition at 23 DEG C and 1 atm is not less than 1.3 mPa.s and not more than 60 mPa.s, the content of the solvent relative to the entire curable composition is not less than 5 vol% and not more than 95 vol%, the boiling point of the solvent at 1 atm is not less than 135 DEG C, and the photopolymerization initiator is not less than 5 vol%. And defining the surface tension of the composition obtained by removing the solvent from the curable composition at 1 atm as [gamma] 1 [mN / m], the surface tension of the solvent at 23 DEG C and 1 atm as [gamma] 2 [mN / m], [gamma] 1 not greater than 30, [gamma] 2 not greater than 24, and [gamma] 1 greater than [gamma] 2.

Description

Technical Field

[0001] The present invention relates to a curable composition, a film forming method and a manufacturing method. Background Art

[0002] For semiconductor devices and MEMS, the requirements of micronization are getting higher and higher, and as a micro-patterning technology, imprinting technology (optical imprinting technology) has received great attention as a micro-machining technology. In imprinting technology, a mold with a fine concave-convex pattern is formed on the surface and the curable composition supplied (applied) to the substrate is contacted to make the curable composition solidified. Therefore, the pattern of the mold is transferred to the cured film of the curable composition, so as to form a pattern on the substrate. According to imprinting technology, a fine pattern (structure) of several nanometers can be formed on the substrate.

[0003] The master mold used in the imprinting technology is very expensive because a fine pattern is formed on the surface of silicon, quartz glass, metal, etc. by precision machining. Therefore, a replica mold is manufactured by the imprinting technology, and the replica mold has a cured product layer on the surface of a mold substrate (such as quartz glass), and the fine pattern of the master mold is transferred to the cured product layer. As a curable composition for forming a cured product layer of a replica mold, Japanese Patent No. 5794387 proposes a composition containing fluorine atoms.

[0004] The method for forming a replica mold using an embossing technique will be described. First, a curable composition in liquid form (curable composition for replica) is discretely dripped (arranged) in a pattern forming area on a mold base material (substrate). The droplets of the curable composition arranged in the pattern forming area are diffused on the mold base material. This phenomenon is called pre-diffusion. Next, the master mold (mold) is contacted (pressed) with the curable composition on the mold base material. Therefore, the droplets of the curable composition are diffused to the entire area of ​​the gap between the mold base material and the master mold by capillary phenomenon. This phenomenon is called diffusion. In addition, by capillary phenomenon, the curable composition fills the concave portion of the pattern forming the master mold. This phenomenon is called filling. Please note that the time until diffusion and filling are completed is called filling time. If the filling of the curable composition is completed, the curable composition is irradiated with light to solidify the curable composition. Then, the master mold is separated from the cured curable composition on the mold base material. By performing these steps, the pattern of the master mold is transferred to the curable composition on the mold base material, and the pattern (cured product layer) of the curable composition is formed.

[0005] However, in the conventional technology, if the mold is brought into contact with the curable composition in a state where the droplets of the curable composition arranged on the substrate are not in contact with each other, the bubbles entrapped between the droplets of the curable composition grow in the space between the mold and the substrate. Therefore, it takes a long time until the bubbles diffuse to the mold or the substrate and disappear, which is one of the factors that reduce productivity (throughput). Summary of the invention

[0006] The present invention provides a new technology regarding curable compositions.

[0007] According to a first aspect of the present invention, a curable composition is provided, which contains a polymerizable compound (a), a photopolymerization initiator (b) and a solvent (c), wherein the viscosity of the curable composition at 23°C and 1atm (1 atmosphere) is not less than 1.3mPa·s and not more than 60mPa·s, the content of the solvent (c) relative to the entire curable composition is not less than 5 volume % and not more than 95 volume %, the boiling point of the solvent (c) at 1atm is not lower than 135°C, and the surface tension of the composition obtained by removing the solvent (c) from the curable composition at 1atm is defined as γ1 [mN / m], the surface tension of the solvent (c) at 23°C and 1atm is defined as γ2 [mN / m], γ1 is not more than 30, γ2 is not more than 24, and γ1 is greater than γ2.

[0008] According to a second aspect of the present invention, a curable composition is provided, comprising a polymerizable compound (a), a photopolymerization initiator (b) and a solvent (c), wherein the viscosity of the curable composition at 23°C and 1 atm is not less than 1.3 mPa·s and not more than 60 mPa·s, the content of the solvent (c) relative to the entire curable composition is not less than 5 volume % and not more than 95 volume %, and the solvent (c) contains one of ethylene glycol di-tert-butyl ether and diethylene glycol methyl tert-butyl ether.

[0009] According to a third aspect of the present invention, a film forming method is provided, which forms a film of a curable composition in a space between a mold and a substrate, the film forming method comprising: discretely arranging a plurality of droplets of the above curable composition on one of the substrate and the mold; waiting until each of the plurality of droplets combines with adjacent droplets to form a liquid film; and after waiting, bringing the mold and the liquid film into contact with each other.

[0010] According to a fourth aspect of the present invention, there is provided a manufacturing method comprising: manufacturing a replica mold by forming a cured film having a pattern corresponding to the master mold pattern on a mold substrate using the above film forming method.

[0011] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figures 1A to 1G It is a diagram for explaining a film forming method according to one aspect of the present invention.

[0013] FIG. 2A to FIG. 2D is a diagram for explaining the flow behavior of a droplet of a curable composition during a waiting step.

[0014] Figures 3A to 3G It is a diagram for explaining a film forming method according to one aspect of the present invention.

[0015] Figure 4 is a diagram showing a comparison between a contact step in a conventional technique and a contact step according to the present invention. DETAILED DESCRIPTION

[0016] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the present invention. A plurality of features are described in the embodiments, but are not limited to the invention requiring all of these features, and a plurality of such features may be appropriately combined. In addition, in the accompanying drawings, the same reference numerals are given to the same or similar configurations, and redundant descriptions thereof will be omitted.

[0017] To provide new technology regarding curable compositions, the present inventors have discovered a curable composition and process conditions that can form a substantially continuous liquid film before droplets of the curable composition discretely disposed on a substrate combine with each other and a mold contacts the curable composition.

[0018] [Curable composition]

[0019] The curable composition (A) according to the present invention is a curable composition for spraying. The curable composition (A) according to the present invention is a composition containing at least: a component (a) as a polymerizable compound, a component (b) as a photopolymerization initiator, and a component (c) as a solvent. The curable composition (A) according to the present invention may further contain: a component (as) as a polymerizable silicon compound, a component (af) as a polymerizable fluorine compound, and at least one of a component (d) as a non-polymerizable compound.

[0020] In this specification, the cured film refers to a film cured by polymerizing a curable composition on a substrate. Note that the shape of the cured film is not particularly limited, and the cured film may or may not have a pattern shape on the surface.

[0021] <Component (as): Silicon-containing polymerizable compound>

[0022] The silicon compound as component (as) can be understood as a silicon-containing polymerizable compound. In this specification, the silicon-containing polymerizable compound is a compound that reacts with a polymerization factor (e.g., free radical) generated by a photopolymerization initiator (component (b)) and forms a film made of a polymer compound through a chain reaction (polymerization reaction).

[0023] An example of the silicon-containing polymerizable compound is a radical polymerizable compound. The polymerizable compound as the component (as) may be formed of only one type of polymerizable compound or may be formed of a plurality of types of polymerizable compounds.

[0024] Examples of the silicon-containing radical polymerizable compound are (meth)acrylate-based compounds, (meth)acrylamide-based compounds, vinylphenyl compounds, aryl ether-based compounds, alkenyl ether-based compounds, and maleimide-based compounds.

[0025] Silicon-containing polymerizable compounds can be straight or branched. As silicon-containing polymerizable compounds, for example, the following structure can be used. The example of the polymerizable functional group in the group Q with polymerizable functional group is a free radical polymerizable functional group. The detailed example of the free radical polymerizable functional group is a (meth) acrylate compound, a (meth) acrylamide compound, a vinyl phenyl compound, an aryl ether compound, an alkenyl ether compound and a maleimide compound. The group Q with polymerizable functional group can be a group with the above-mentioned polymerizable functional group.

[0026]

[0027]

[0028] In addition, examples of silicon-containing polymerizable compounds are silsesquioxane skeletons indicated by the following formula (1) and silicone skeletons indicated by the following formula (2). Here, in formula (1), m+n=8 (8≥m≥1), and R1 is a divalent organic group. In addition, in formula (2), A, B, R2 and R3 are independently alkyl, cycloalkyl, alkoxy, phenyl or hydroxyl groups having 1 to 6 carbon atoms (t is an integer from 1 to 3), and at least one of A and B is a polymerizable functional group.

[0029]

[0030] Examples of polymerizable functional groups in the groups Q, A and B having polymerizable functional groups are free radical polymerizable functional groups. Detailed examples of free radical polymerizable functional groups are (meth) acrylate-based compounds, (meth) acrylamide-based compounds, vinylphenyl compounds, aryl ether-based compounds, alkenyl ether-based compounds and maleimide-based compounds. The group Q having a polymerizable functional group may be a group having the above-mentioned polymerizable functional groups.

[0031] Silicon-containing (meth)acrylate compounds include compounds having one or more acryloyl groups or methacryloyl groups. Examples of silicon-containing monofunctional (meth)acrylate compounds having one acryloyl group or methacryloyl group are as follows, but the compounds are not limited to these examples. (2-Acryloylethoxy)trimethylsilane,

[0032] N-(3-acryloyl-2-hydroxypropyl)-3-aminopropyltriethoxysilane, acryloxymethyltrimethoxysilane,

[0033] (Acryloyloxymethyl)phenethyltrimethoxysilane,

[0034] Acryloyloxymethyltrimethylsilane,

[0035] (3-Acryloxypropyl)dimethylmethoxysilane,

[0036] (3-Acryloxypropyl)methylbis(trimethylsiloxy)silane,

[0037] (3-Acryloxypropyl)methyldichlorosilane,

[0038] (3-Acryloxypropyl)methyldiethoxysilane,

[0039] (3-Acryloxypropyl)methyldimethoxysilane,

[0040] (3-Acryloxypropyl)trichlorosilane,

[0041] (3-Acryloxypropyl)trimethoxysilane,

[0042] (3-acryloxypropyl)tris(trimethylsiloxy)silane, acryloxytriisopropylsilane,

[0043] Acryloyloxytrimethylsilane,

[0044] Methacryloxymethyltrimethoxysilane,

[0045] O-(methacryloyloxyethoxy)carbamoylpropylmethyldimethoxysilane, (methacryloyloxymethyl)bis(trimethylsiloxy)methylsilane, N-(3-methacryloyl-2-hydroxypropyl)-3-aminopropyltriethoxysilane,

[0046] (Methacryloxymethyl)methyldimethoxysilane,

[0047] (Methacryloxymethyl)methyldiethoxysilane,

[0048] Methacryloxymethyltriethoxysilane,

[0049] Methacryloxypropyltrimethoxysilane,

[0050] Methacryloylpropyltriisopropoxysilane,

[0051] O-(methacryloyloxyethyl)-N-(triethoxysilylpropyl) carbamate, methacryloxypropylmethyldimethoxysilane,

[0052] Methacryloxypropylmethyldiethoxysilane,

[0053] Methacryloxypropyl dimethylmethoxysilane,

[0054] Methacryloxypropyl dimethylethoxysilane,

[0055] (Methacryloxymethyl)dimethylethoxysilane,

[0056] Methacryloxypropyltriethoxysilane,

[0057] Methacryloxypropylsilane,

[0058] Methacryloylpentamethyldisiloxane,

[0059] (Methacryloxymethyl)phenyldimethylsilane,

[0060] Methacryloxytrimethylsilane,

[0061] Methacryloxymethyltrimethylsilane,

[0062] (3-methacryloyloxy-2-hydroxypropoxypropyl)methylbis(trimethylsiloxy)silane,

[0063] Methacryloyloxypropyl pentamethyldisiloxane,

[0064] O-(Methacryloyloxyethyl)-3-[bis(trimethylsiloxy)methylsilyl]propylcarbamate,

[0065] Methacryloxymethyltris(trimethylsiloxy)silane,

[0066] Methacryloxyethoxytrimethylsilane,

[0067] (3-methacryloyloxy-2-hydroxypropoxypropyl)methylbis(trimethylsiloxy)silane,

[0068] Methacryloxypropyl tris(vinyldimethylsiloxy)silane, methacryloxypropyl tris(trimethylsiloxy)silane,

[0069] 3-methacryloxypropyltriacetoxysilane,

[0070] Methacryloyloxypropylmethyldichlorosilane,

[0071] Methacryloyloxypropyltrichlorosilane,

[0072] 3-Methacryloxypropylbis(trimethylsiloxy)methylsilane,

[0073] 3-Methoxypropyldimethylsilyl chloride,

[0074] O-methacryloyloxy (polyethyleneoxy) trimethylsilane,

[0075] Poly(methacryloxypropylsilsesquioxane),

[0076] Methacryloxypropyl heptaisobutyl-T8-silsesquioxane, and

[0077] Methacryloxypropyltris(trimethylsiloxy)silane.

[0078] Examples of commercially available products of the above silicon-containing monofunctional (meth)acrylic compound are as follows, but the products are not limited to these examples.

[0079] SIA0160.0, SIA0180.0, SIA0182.0, SIA0184.0, SIA0186.0, SIA0190.0, SIA0194.0, SIA0196.0, SIA01 97.0, SIA0198.0, SIA0199.0, SIA0200.0, SIA0200.A1, SIA0210.0, SIA0315.0, SIA0320.0, SIM6483.0, SIM6487.5, SIM6480.76, SIM6481.2, SIM6486.1, SIM6481.1, SIM6481.46, SIM6481.43, SIM6482.0, SI M6487.4, SIM6487.35, SIM6480.8, SIM6486.9, SIM6486.8, SIM6486.5, SIM6486.4, SIM6481.3, SIM6487 .3. SIM6487.1, SIM6487.6, SIM6486.14, SIM6481.48, SIM6481.5, SIM6491.0, SIM6485.6, SIM6481.15 , SIM6487.0, SIM6481.05, SIM6485.8, SIM6481.0, SIM6487.4LI, SIM6481.16, SIM6487.8, SIM6487.6HP , SIM6487.17, SIM6486.7, SIM6487.2, SIM6486.0, SIM6486.2, SIM6487.6-06, SIM6487.6-20, SIM6485.9, SST-R8C42, SLT-3R01, and SIM6486.65 (manufactured by GELEST) and TM-0701T, FM-0711, FM-0721, and FM-0725 (manufactured by JNC)

[0080] The silicon-containing (meth)acrylamide-based compound includes a compound having one or more acrylamide groups or methacrylamide groups. Examples of the silicon-containing monofunctional (meth)acrylamide-based compound having one acrylamide group or methacrylamide group are as follows, but the compound is not limited to these examples.

[0081] 3-Acrylamidopropyltrimethoxysilane, and 3-acrylamidopropyltri(trimethylsiloxy)silane.

[0082] Examples of commercially available products of the above silicon-containing monofunctional (meth)acrylamide compound are as follows, but the products are not limited to these examples.

[0083] SIA0146.0 and SIA0150.0 (manufactured by GELEST)

[0084] Examples of the multifunctional (meth)acrylate-based compound having two or more acryloyl groups or methacryloyl groups are as follows, but the compound is not limited to these examples.

[0085] Linear polydimethylsiloxane modified with acryloyloxypropyl groups at both ends,

[0086] Linear polydimethylsiloxane modified with methacryloxypropyl groups at both ends, cyclic siloxane modified with multiple acryloxypropyl groups,

[0087] Cyclic siloxane modified with multiple methacryloxypropyl groups,

[0088] Silsesquioxane modified with multiple acryloxypropyl groups, and

[0089] Silsesquioxane is modified with multiple methacryloxypropyl groups.

[0090] Examples of commercially available products of the above silicon-containing monofunctional (meth)acrylate compound are as follows, but the products are not limited to these examples.

[0091] SIA0200.2, SIA0200.3, SIM6487.42, DMS-R11, DMS-R05, DMS-R22, DMS-R18, DMS-R31 (manufactured by GELEST),

[0092] FM-7711, FM-7721, FM-7725 (manufactured by JNC),

[0093] X-22-2445 (manufactured by Shin-Etsu Chemical), and AC-SQ TA-100, MAC-SQ TM-100, AC-SQ SI-20, MAC-SK SI-20 (manufactured by TOAGOSEI).

[0094] In addition, for example, the following compounds can be synthesized and / or obtained from the known document 1. A linear modified polydimethylsiloxane (MA-Si-12) having methacryloxypropyl groups at both ends, an 8-membered cyclosiloxane (8 rings) modified with four methacryloxypropyl groups, and a 10-membered cyclosiloxane (10 rings) modified with five methacryloxypropyl groups.

[0095] Reference 1: Ogawa et al. “Ultraviolet curable branched siloxanes as low-k dielectrics for imprint lithography”

[0096] <Component (a): Silicon-free polymerizable compound>

[0097] Component (a) contains a silicon-free polymerizable compound. In this specification, the silicon-free polymerizable compound is a compound that reacts with a polymerization factor (such as a radical) generated by a photopolymerization initiator (component (b)) and forms a film made of a polymer compound through a chain reaction (polymerization reaction).

[0098] An example of the above-mentioned polymerizable compound is a radical polymerizable compound.The polymerizable compound as component (a) may be formed of only one type of polymerizable compound, and may also be formed of a plurality of types (one or more types) of polymerizable compounds.

[0099] Examples of the radical polymerizable compound are silicon-free (meth)acrylic compounds, silicon-free styrene-based compounds, silicon-free vinyl-based compounds, silicon-free allyl-based compounds, silicon-free fumaric acid compounds, and silicon-free maleic acid compounds.

[0100] <Component (af): Fluorine-containing polymerizable compound>

[0101] The fluorine compound as component (af) can be understood as a fluorine-containing polymerizable compound. In this specification, the fluorine-containing polymerizable compound is a compound that reacts with a polymerization factor (such as a free radical) generated by a photopolymerization initiator (component (b)) and forms a film made of a polymer compound through a chain reaction (polymerization reaction).

[0102] An example of the fluorine-containing polymerizable compound is a radical polymerizable compound. The polymerizable compound as component (af) may be formed of only one type of polymerizable compound or may be formed of a plurality of types (one or more types) of polymerizable compounds.

[0103] Examples of the fluorine-containing radical polymerizable compound are (meth)acrylate-based compounds, (meth)acrylamide-based compounds, vinylphenyl compounds, aryl ether-based compounds, alkenyl ether-based compounds, and maleimide-based compounds.

[0104] Examples of commercially available products of the above-mentioned fluorine-containing monofunctional (meth)acrylate-based compound are as follows, but the products are not limited to these examples.

[0105] 2,2,2-trifluoroethyl acrylate, 2,2,3,4,4-hexafluorobutyl methacrylate, 1,1,1,3,3,3-hexafluoroisopropyl acrylate, 2,3,3,3,3-hexafluoroisopropyl methacrylate, 2,2,3,3,4-tetrafluorobutyl acrylate, 2,2,2-trifluoroethyl methacrylate, 1,1,1,3,3,4-3-hexafluoroisopropyl methacrylate, 1H,1H,2H,2H nonafluorohexyl methacrylate, 1H,1H,2H,2H-nonafluorohexyl methacrylate, 1H,1H,5H-octafluoropentyl methacrylate, pentafluorophenyl acrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, Pentafluorobenzyl methacrylate, methylpropane 2,2,3,3-tetrafluoropropyl acrylate, methacrylate 1H,1H,2H,2H-trifluorooctyl, acrylate 1H,1H,2H,2H,1H-trifluorooctyl, methacrylate 2,2,3,3-tetrafluoropropyl, acrylate 1H,1H,2H,2H-heptadecafluorodecyl, acrylate 2,2,,3,4,4,4,5,6,6,7-dodecafluoroheptyl, methacrylate 2,2,3,4,5,5,6,6,7,7-dodecafluorooctyl, acrylate 1H,1H,5H octafluoropentyl, methyl pentafluorophenyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0106] C6 (meth)acrylate, C4 (meth)acrylate, C2 (meth)acrylate (manufactured by Uni-chem)

[0107] Viscat 3F, Viscat 4F, Viscat 8F, Viscat 8FM, Viscat 13F (manufactured by OSAKA ORGANIC CHEMICAL INDUSTRY)

[0108] 1H,1H,2H,2H heptadecafluorodecyl methacrylate, 1,1,1,3,3-hexafluoroisopropyl methacrylate, 1H,1H,5H octafluoropentyl methacrylate, pentafluorophenyl acrylate, 2,2,2-trifluoroethyl acrylate, 2,2,2-trifluoroethyl methacrylate (manufactured by Polysciences)

[0109] Methyl-2-fluoroacrylate, 2,2,2-trifluoroethyl acrylate, 2,2,3,3,3-pentafluoropropyl acrylate, 2-(perfluorobutyl)ethyl acrylate, 3-perfluorohexyl-2-hydroxypropyl acrylate, 1H,1H,3H-tetrafluoropropyl acrylate, 1H,1H,5H-octafluoropentyl acrylate, 1H-1,1H,7H-dodecafluoroheptyl acrylate, 1H-1-(trifluoromethyl)trifluoroethyl acrylate, 1H,1H,3H-hexafluorobutyl acrylate, 2,2-2-trifluoroethyl methacrylate, 2,2,4,3,3-pentafluoropropyl methacrylate, 2-methacrylate, methacrylate 1H,1H,7H dodecafluoroheptyl methacrylate, methacrylate 1H-1-(trifluoromethyl)trifluoroethyl ester, methacrylate 1H,1H,3H hexafluorobutyl ester (manufactured by DAIKIN)

[0110] Examples of the above-mentioned fluorine-containing multifunctional (meth)acrylate-based compound obtained using the method disclosed in Japanese Patent No. 3963028 are as follows, but the compound is not limited to these examples.

[0111] A compound obtained by introducing a linking group into the polyol portion of trivalent trimethylolethane, tetravalent pentaerythritol or hexavalent dipentaerythritol using a normal organic synthesis reaction, forming a core portion with a high fluorine content through a fluorination reaction, and then introducing an acrylic acid group at the terminal.

[0112] The silicon-free (meth)acrylic compound includes a compound having one or more acryloyl groups or methacryloyl groups. Examples of the silicon-free monofunctional (meth)acrylic compound having one acryloyl group or methacryloyl group are as follows, but the compound is not limited to these examples.

[0113] 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, EO-modified p-cumylphenol (meth)acrylate, 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, poly Oxyethylene nonylphenyl ether (meth)acrylate, isobornyl (meth)acrylate, 1-adamantyl (meth)acrylate, 2-methyl-2-adamantyl (meth)acrylate, 2-ethyl-2-adamantyl (meth)acrylate, boron (meth)acrylate, tricyclodecyl (meth)acrylate, dicyclopentyl (meth)acrylate, dicyclopentenyl (meth)acrylate, cyclohexyl (meth)acrylate, 4-butylcyclohexyl (meth)acrylate, acryloylmorpholine, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, (meth) Isopropyl acrylate, butyl (meth)acrylate, amyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (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, tetrahydrofurfuryl (meth)acrylate, (meth)acrylate Butoxyethyl (meth)acrylate, ethoxydiglycol (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, tert-octyl (meth)acrylamide, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 7-amino-3,7-dimethyloctyl (meth)acrylate, N,N-diethyl (meth)acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, 1- or 2-naphthyl (meth)acrylate, 1- or 2-naphthylmethyl (meth)acrylate, 3- or 4-phenoxybenzyl (meth)acrylate, and cyanobenzyl (meth)acrylate.

[0114] Examples of commercially available products of the above-mentioned silicon-free monofunctional (meth)acrylic compound are as follows, but the products are not limited to these examples.

[0115] M101, M102, M110, M111, M113, M117, M5700, TO-1317, M120, M150, and M156 (manufactured by TOAGOSEI)

[0116] MEDOL10, MIBDOL10, CHDOL10, MMDOL30, MEDOL30, MIBDOL30, CHDOL30, LA, IBXA, 2-MMA, HPA, and Viscoat #150, #155, #158, #190, #192, #193, #220, #2000, #2100, and #2150 (manufactured by Osaka Organic Chemical Industry)

[0117] Light acrylate BO-A, EC-A, DMP-A, THF-A, HOP-A, HOA-MPE, HOA-MPL, PO-A, P-200A, NP-4EA, NP-8EA, epoxy ester M-600A, POB-A, and OPP-EA (manufactured by KYOEISHA CHEMICAL)

[0118] TC110S, R-564 and R-128H (manufactured by NIPPON KAYAKU) NK ester AMP-10G, AMP-20G and A-LEN-10 (manufactured by SHIN-NAKAMURA CHEMICAL)

[0119] FA-511A, 512A and 513A (manufactured by Hitachi Chemical)

[0120] PHE, CEA, PHE-2, PHE-4, BR-31, BR-31M and BR-32 (manufactured by DKS) VP (manufactured by BASF)

[0121] and ACMO, DMAA and DMAPAA (manufactured by Kohjin).

[0122] Examples of the silicon-free multifunctional (meth)acrylic compound having two or more acryloyl groups or methacryloyl groups are as follows, but the compound is not limited to these examples.

[0123] Trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropylene tri(meth)acrylate, PO-modified trimethylolpropylene di(meth)acrylate, EO- and PO-modified trimethylolpropylene tri(meth)acrylate, dimethyloltricyclodecane di(meth)acrylate, 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(methyl ester)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(methyl ester)acrylate, 1,9-nonanediol di(meth)acrylate Acrylates, 1,10-decanediol di(methyl)acrylate, 1,3-adamantanedimethanol di(meth)acrylate, tri(2-hydroxyethyl)isocyanurate tri(meth)acrylate, tri(acryloxy)isocyanurate, bis(hydroxymethyl)tricyclodecane di(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipropylenetriol hexa(meth)acrylate, EO-modified 2,2-bis(4-((meth)acryloyloxy)phenyl)propane, PO-modified 2,2-bis(4-((meth)propionyloxy)phenyl)propane, EO- and PO-modified 2,2-bis(4-((meth)acrylamido)phenyl)propane, o-, m- or p-terephthalene di(meth)acrylate, and o-, m- or p-xylene di(meth)acrylate.

[0124] Examples of commercially available products of the above-mentioned silicon-free multifunctional (meth)acrylic compound are as follows, but the products are not limited to these examples.

[0125] UV SA1002 and SA2007 (manufactured by Mitsubishi Chemical)

[0126] Viscoat #195, #230, #215, #260, #335HP, #295, #300, #360, #700, GPT and 3PA (manufactured by OSAKA ORGANIC CHEMICAL INDUSTRY)

[0127] Lightweight acrylates 4EG-A, 9EG-A, NP-A, DCP-A, BP-4EA, BP-4PA, TMP-A, PE-3A, PE-4A, and DPE-6A (manufactured by KYOEISHA CHEMICAL)

[0128] PET-30, TMPTA, R-604, DPHA, DPCA-20, -30, -60 and -120, HX-620, D-310 and D-330 (manufactured by NIPPON KAYAKU)

[0129] M208, M210, M215, M220, M240, M305, M309, M310, M315, M325, and M400 (manufactured by TOAGOSEI)

[0130] VR-77, VR-60 and VR-90 (manufactured by Showa Highpolymer)

[0131] OGSOL EA-0200 and OGSOL EA-0300 (manufactured by Osaka Gas Chemicals)

[0132] Note that in the above compound group (county), (meth)acrylate refers to acrylate or methacrylate in which the alcohol residue is equal to acrylate. (Meth)acryloyl refers to acryloyl or methacryloyl having an alcohol residue equal to acryloyl. EO indicates ethylene oxide, and EO-modified compound A indicates a compound in which the (meth)acrylic acid residue and the alcohol residue of compound A are combined via a block structure of an ethylene oxide group. In addition, PO indicates propylene oxide, and PO-modified compound B indicates a compound in which the (meth)acrylic acid residue and the alcohol residue of compound B are combined via a block structure of a propylene oxide group.

[0133] Practical examples of the silicon-free styrene-based compound are as follows, but the compound is not limited to these examples. Alkyl styrenes such as styrene, 2,4-dimethyl-α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 2,6-dimethylstyrene, 3,4-dimethylstyrene, 3,5-dimethylstyrene, 2,4,6-trimethylstyrene, 2,4,5-trimethylstyrene and pentamethylstyrene, o-ethylstyrene, m-ethylstyrene, p-ethylstyrene, diethylstyrene, triethylstyrene, propylstyrene 2,4-diisopropylstyrene, butylstyrene, hexylstyrene, heptylstyrene and octylstyrene; halogenated styrenes such as fluorostyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, o-bromostyrene, m-bromostyrene, p-bromostyrene Styrene, dibromostyrene and iodostyrene; and compounds having a styryl group as a polymerizable functional group, such as nitrosostyrene, acetylstyrene, o-methoxystyrene, m-methoxystyrene, p-methoxyethylene, o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, 2-vinylbiphenyl, 3-vinylbiphenyl, 4-vinylbiphenyl, 1-vinylnaphthalene, 2-vinylnaphthalene, 4-vinyl-p-thienyl, 1-vinylanthracene, α-methylstyrene, o-isopropenyltoluene, m-isopropenyltoluene, p-isopropenyltoluene, 2,3-dimethyl-α-methylstyrene, 3,5-dimethyl-α-methylstyrene, p-isopropyl-α-methylstyrene, α-ethylstyrene, α-chlorostyrene, divinylbenzene, diisopropylbenzene and divinylbiphenyl.

[0134] Examples of the silicon-free vinyl compound are as follows, but the compound is not limited to these examples.

[0135] Vinyl pyridine, vinyl pyrrolidone, vinyl carbazole, vinyl acetate and acrylonitrile; conjugated diene monomers such as butadiene, isoprene and chloroprene; vinyl halides such as vinyl chloride and vinyl bromide; compounds having a vinyl group as a polymerizable functional group, for example, vinylidene halides such as vinylidene chloride, organic carboxylic acid vinyl esters and their derivatives (for example, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate and divinyl adipate) and (meth)acrylonitrile.

[0136] Note that in this specification, (meth)acrylonitrile is a general term for acrylonitrile and methacrylonitrile.

[0137] Examples of the silicon-free allyl compound are as follows, but the compound is not limited to these examples.

[0138] Allyl acetate, allyl benzoate, diallyl adipate, diallyl terephthalate, diallyl isophthalate and allyl phthalate.

[0139] Examples of the silicon-free fumaric acid compound are as follows, but the compound is not limited to these examples.

[0140] dimethyl fumarate, diethyl fumarate, diisopropyl fumarate, di-sec-butyl fumarate, diisobutyl fumarate, di-n-butyl fumarate, di-2-ethylhexyl fumarate and dibenzyl fumarate.

[0141] Examples of the silicon-free maleic acid compound are as follows, but the compound is not limited to these examples.

[0142] dimethyl maleate, diethyl maleate, diisopropyl maleate, di-tert-butyl maleate, diisobutyl maleate, di-n-butyl maleate, di-2-ethylhexyl maleate and dibenzyl maleate.

[0143] Other examples of the silicon-free radical polymerizable compound are as follows, but the compound is not limited to these examples.

[0144] Dialkyl esters of itaconic acid and their derivatives (for example, dimethyl itaconate, diethyl itaconate, diisopropyl itaconate, di-sec-butyl itaconate, diisobutyl itaconate, di-n-butyl itaconate, di-2-ethylhexyl itaconate and dibenzyl itaconate), N-vinylamide derivatives of organic carboxylic acids (for example, N-methyl-N-vinylacetamide) and maleimide and its derivatives (such as N-phenylmaleimide and N-cyclohexylmaleimide).

[0145] If component (a) is formed by a variety of compounds having one or more polymerizable functional groups, it is preferably composed of monofunctional compounds and polyfunctional compounds. This is because, if monofunctional compounds and polyfunctional compounds are combined, a cured film with good balance properties (e.g., high mechanical strength, high dry etching resistance and high heat resistance) can be obtained.

[0146] The film forming method of the present invention takes several milliseconds to several hundred seconds until the droplets of the curable composition (A) discretely arranged on the substrate combine with each other and form a practically continuous liquid film, so a waiting step (described later) is required. In this waiting step, the solvent (c) volatilizes, but the polymerizable compound (a) does not volatilize. Therefore, in the polymerizable compound (a) that may contain various types of compounds, the boiling point of all compounds at normal pressure is preferably above 250°C, more preferably above 300°C, and further preferably above 350°C. In addition, in order to obtain high dry etching resistance and high heat resistance, the cured film of the curable composition (A) preferably contains at least a compound having a cyclic structure (such as an aromatic structure, an aromatic heterocyclic structure or an alicyclic structure). Note that normal pressure is assumed to be 1atm (atmospheric pressure).

[0147] The boiling point of the polymerizable compound (a) is almost related to the molecular weight. Therefore, the molecular weight of all polymerizable compounds (a) is preferably 200 or more, more preferably 240 or more, and further preferably 250 or more. However, even if the molecular weight is 200 or less, if the boiling point is 250° C. or more, the compound is preferably used as the polymerizable compound (a) of the present invention.

[0148] In addition, the vapor pressure of the polymerizable compound (component (a)) at 80° C. is preferably 0.001 mmHg or less. This is because, although heating the curable composition is advantageous in accelerating the volatilization of the solvent (component (c)) (described later), the volatilization of the polymerizable compound (component (a)) needs to be suppressed during the heating process.

[0149] Note that the boiling point and vapor pressure of each organic compound at normal pressure can be determined by, for example,

[0150] The Hansen solubility parameters in “HSPiP Practice (HSPiP) 5th Edition.5.3.04” were used for calculation.

[0151] Practical examples of the polymerizable compound (component (a)) having a boiling point of 250° C. or higher are as follows, but the compound is not limited to these examples.

[0152] Dicyclopentyl acrylate (boiling point = 262°C, molecular weight = 206)

[0153] Dicyclopentenyl acrylate (boiling point = 270°C, molecular weight = 204)

[0154] 1,3-Cyclohexanedimethanol diacrylate (boiling point = 310°C, molecular weight = 252)

[0155] Meta-xylene diacrylate (boiling point = 336°C, molecular weight = 246)

[0156] 1,4-Cyclohexanedimethanol diacrylate (boiling point = 339°C, molecular weight = 252)

[0157] 4-Hexyl resol phenolic resin diacrylate (boiling point = 379°C, molecular weight = 302)

[0158] 6-phenylhexane-1,2-diol diacrylate (boiling point = 381°C, molecular weight = 302)

[0159] 7-phenylheptane-1,2-diol diacrylate (boiling point = 393°C, molecular weight = 316)

[0160] 1,3-Bis((2-hydroxyethoxy)methyl)cyclohexane diacrylate (boiling point = 403°C, molecular weight = 340)

[0161] 8-Phenyloctane-1,2-diol diacrylate (boiling point = 404°C, molecular weight = 330)

[0162] 1,3-Bis((2-hydroxyethoxy)methyl)benzene diacrylate (boiling point = 408°C, molecular weight = 334) 1,4-Bis((2-hydroxyethoxy)methyl)cyclohexane diacrylate (boiling point = 445°C, molecular weight = 340)

[0163] 3-Phenoxybenzyl acrylate (mPhOBzA, OP = 2.54, boiling point = 367.4 ° C, 80 ° C vapor pressure = 0.0004 mmHg, molecular weight = 254.3)

[0164]

[0165] 1-Naphthyl acrylate (NaA, OP = 2.27, boiling point = 317 ° C, 80 ° C vapor pressure = 0.0422 mmHg, molecular weight = 198)

[0166]

[0167] 2-Phenoxyethyl acrylate (PhPhOEA, OP = 2.57, boiling point = 364.2 ° C, 80 ° C vapor pressure = 0.0006 mmHg, molecular weight = 268.3)

[0168]

[0169] 1-Naphthylmethyl acrylate (Na1MA, OP = 2.33, boiling point = 342.1 ° C, 80 ° C vapor pressure = 0.042 mmHg, molecular weight = 212.2)

[0170]

[0171] 2-Naphthylmethyl acrylate (Na2MA, OP = 2.33, boiling point = 342.1°C, vapor pressure at 80°C = 0.042 mmHg, molecular weight = 212.2)

[0172]

[0173] 4-Benzyl cyanoacrylate (CNBzA, OP = 2.44, boiling point = 316 ° C, molecular weight = 187)

[0174]

[0175] DVBzA represented by the following molecular formula (OP = 2.50, boiling point = 304.6°C, vapor pressure at 80°C = 0.0848 mmHg, molecular weight = 214.3)

[0176]

[0177] DPhPA represented by the following molecular formula (OP = 2.38, boiling point = 354.5°C, vapor pressure at 80°C = 0.0022 mmHg, molecular weight = 266.3)

[0178]

[0179] PhBzA represented by the following molecular formula (OP = 2.29, boiling point = 350.4°C, vapor pressure at 80°C = 0.0022 mmHg, molecular weight = 238.3)

[0180]

[0181] FLMA represented by the following molecular formula (OP = 2.20, boiling point = 349.3°C, vapor pressure at 80°C = 0.0018 mmHg, molecular weight = 250.3)

[0182]

[0183] ATMA represented by the following molecular formula (OP = 2.13, boiling point = 414.9°C, vapor pressure at 80°C = 0.0001 mmHg, molecular weight = 262.3)

[0184]

[0185] DNaMA represented by the following molecular formula (OP = 2.00, boiling point = 489.4 ° C, 80 ° C vapor pressure < 0.0001 mmHg, molecular weight = 338.4)

[0186]

[0187] Tricyclodecane dimethanol diacrylate (DCPDA, OP = 3.29, boiling point = 342 ° C, 80 ° C vapor pressure <0.0024 mmHg, molecular weight = 304)

[0188]

[0189] Meta-xylene diacrylate (mXDA, OP = 3.20, boiling point = 336 ° C, 80 ° C vapor pressure <0.0043 mmHg, molecular weight = 246)

[0190]

[0191] 1-phenylethane-1,2-diyl diacrylate (PhEDA, OP = 3.20, 80°C vapor pressure < 0.0057 mmHg, boiling point = 354°C, molecular weight = 246)

[0192]

[0193] 2-Phenyl-1,3-propanediol diacrylate (PhPDA, OP = 3.18, boiling point = 340 ° C, 80 ° C vapor pressure < 0.0017 mmHg, molecular weight = 260)

[0194]

[0195] VmXDA represented by the following molecular formula (OP = 3.00, boiling point = 372.4°C, vapor pressure at 80°C = 0.0005 mmHg, molecular weight = 272.3)

[0196]

[0197] BPh44DA represented by the following molecular formula (OP = 2.63, boiling point = 444 ° C, 80 ° C vapor pressure < 0.0001 mmHg, molecular weight = 322.3)

[0198]

[0199] BPh43DA represented by the following molecular formula (OP = 2.63, boiling point = 439.5 ° C, 80 ° C vapor pressure < 0.0001 mmHg, molecular weight = 322.3)

[0200]

[0201] DPhEDA represented by the following molecular formula (OP = 2.63, boiling point = 410°C, vapor pressure at 80°C < 0.0001 mmHg, molecular weight = 322.3)

[0202]

[0203] BPMDA represented by the following molecular formula (OP = 2.68, boiling point = 465.7 ° C, 80 ° C vapor pressure < 0.0001 mmHg, molecular weight = 364.4)

[0204]

[0205] Na13MDA represented by the following molecular formula (OP = 2.71, boiling point = 438.8 ° C, 80 ° C vapor pressure < 0.0001 mmHg, molecular weight = 296.3)

[0206]

[0207] The amount of component (as) or component (af) in component (a) is preferably 1% by weight or more and 99% by weight or less. The amount of component (as) or component (af) is more preferably 50% by weight or more and 95% by weight or less, and further preferably 60% by weight or more and 90% by weight or less.

[0208] At least a portion of component (a), which may include various types of additive components, may be a polymer having a polymerizable functional group. The polymer preferably contains at least a cyclic structure, such as an aromatic structure, an aromatic heterocyclic structure, or an alicyclic structure. For example, the polymer preferably contains at least one of the constituent units represented by the following molecular formulas (3) to (8):

[0209]

[0210] In the molecular formulae (3) to (8), the substituents R are substituents containing a partial structure each independently containing an aromatic ring, 1 is a hydrogen atom or a methyl group. In the present specification, in the constituent units represented by molecular formulae (3) to (8), the portion other than R is the main chain of the specific polymer. The formula molecular weight of the substituent R is 80 or more, preferably 100 or more, more preferably 130 or more, and further preferably 150 or more. The upper limit of the formula molecular weight of the substituent R is actually 500 or less.

[0211] The polymer with a polymerizable functional group is generally a compound with a weight average molecular weight of 500 or more. The weight average molecular weight is preferably 1000 or more, more preferably 2000 or more. The upper limit of the weight average molecular weight is not particularly determined, but it is preferably, for example, 50000 or less. When the weight average molecular weight is set above the above lower limit, the boiling point can be set above 250°C, and the mechanical properties after curing are further improved. In addition, when the weight average molecular weight is set below the above upper limit, the solubility in the solvent increases, and the fluidity of the discretely arranged droplets is maintained because the viscosity is not too high. This makes it possible to further improve the flatness of the liquid film surface. Note that, unless otherwise specifically stated, the weight average molecular weight (Mw) in the present invention is a molecular weight measured by gel permeation chromatography (GPC).

[0212] Practical examples of the polymerizable functional group of the polymer are a (meth)acryloyl group, an epoxy group, an oxetanyl group, a hydroxymethyl group, a hydroxymethyl ether group, and an alkenyl ether group. From the viewpoint of ease of polymerization, a (meth)acryloyl group is particularly advantageous.

[0213] When adding a polymer having a polymerizable functional group as at least a part of component (a), the mixing ratio can be freely set as long as the mixing ratio falls within the viscosity adjustment range described later. For example, the mixing ratio of the total mass of all components other than the polymer and the solvent (c) is preferably 0.1% by weight or more and 60% by weight or less, more preferably 1% by weight or more and 50% by weight or less, and further preferably 10% by weight or more and 40% by weight or less. When the mixing ratio of the polymer having a polymerizable functional group is set to 0.1% by weight or more, heat resistance, dry etching resistance, mechanical strength and low volatility can be improved. In addition, when the mixing ratio of the polymer having a polymerizable functional group is set to 60% by weight or less, the mixing ratio can be made to fall within the range of the viscosity upper limit adjustment (described later).

[0214] <Component (b): Photopolymerization Initiator>

[0215] Component (b) is a photopolymerization initiator. In the present specification, a photopolymerization initiator is a compound that senses light having a predetermined wavelength and generates the polymerization factor (free radical) described above. More specifically, a photopolymerization initiator is a polymerization initiator (free radical generator) that generates free radicals by light (infrared light, visible light, ultraviolet light, far ultraviolet light, X-rays, charged particle beams such as electron beams, or radiation). Component (b) may be formed of only one type of photopolymerization initiator, and may also be formed of multiple types of photopolymerization initiators.

[0216] Examples of the radical generator are as follows, but the radical generator is not limited to these examples.

[0217] 2,4,5-triaryl imidazole dimers which may have a substituent, such as 2-(o-chlorophenyl)-4,5-diphenyl imidazole dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl) imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenyl imidazole dimer, and 2-(o- or p-methoxyphenyl)-4,5-diphenyl imidazole dimer; benzophenone derivatives, such as benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone (mishile ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone; benzophenone and 4,4'-diaminobenzophenone; α-aminoaromatic ketone derivatives, such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one; quinones, such as 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2-methyl-1,4-naphthoquinone and 2,3-dimethylanthraquinone; benzoin ether derivatives, such as benzoin methyl ether, benzoin ethyl ... ethers and benzoin phenyl ethers; benzoin derivatives such as benzoin, methyl benzoin, ethyl benzoin and propyl benzoin; benzyl derivatives such as benzyl 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-hydroxyhexyl phenone 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-trimethylthioxanthone; Benzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide; oxime ester derivatives, such as 1,2-octanedione, 1-[4-(benzenethiol)-, 2-(O-benzoyloxime)], ethyl ketone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]- and 1-(O-acetoxime); and oxanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-1-one and 2-hydroxy-2-methyl-1-phenylpropane-1-one.

[0218] Examples of commercially available products of the above-mentioned free radical generators are as follows, but the products are not limited to these examples. Irgacure 184, 369, 651, 500, 819, 907, 784 and 2959, CGI-1700, -1750 and -1850, CG24-61, Darocur 1116 and 1173, TPO, LR8893 and LR8970 (manufactured by BASF), and Ubecryl P36 (manufactured by University of California, Berkeley (UCB)).

[0219] Among the above-mentioned radical generators, component (b) is preferably an acylphosphine oxide-based polymerization initiator. Note that, among the above-mentioned radical generators, the acylphosphine oxide-based polymerization initiator is as follows.

[0220] Acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0221] The mixing ratio of component (b) in curable composition (A) relative to the sum (i.e. the total mass of all components outside solvent (c)) of component (a), component (b) and component (d) (described later) is preferably 0.1% by weight or more and 50% by weight or less. In addition, the mixing ratio of component (b) relative to the total mass of all components outside solvent (c) in curable composition (A) is more preferably 0.1% by weight or more and 20% by weight or less, further preferably 1% by weight or more and 20% by weight or less. When the mixing ratio of component (b) is set to more than 0.1% by weight, the curing rate of composition increases, so the reaction efficiency can be improved. In addition, when the mixing ratio of component (b) is set to less than 50% by weight, a cured film with certain mechanical strength can be obtained.

[0222] <Component (c): Solvent>

[0223] The curable composition (A) contains a solvent as component (c), the boiling point of the solvent at normal pressure is 135° C. or higher and 250° C. or lower, and the surface tension at normal temperature is 24 [mN / m] or lower. Component (c) contains, for example, 10 atomic % or lower of silicon atoms or fluorine atoms. Component (c) is a solvent that dissolves components (a), (b) and (d), and examples are ether hydrocarbon solvents, perfluorocarbon solvents, fluorine-containing alcohol solvents, ester-based fluorinated solvents and halogenated fluorinated solvents.

[0224] Another example of component (c) is a polyol ether obtained by alkyl etherifying all the hydroxyl groups of the polyol ether. Yet another example of component (c) is ethylene glycol di-tert-butyl ether or diethylene glycol methyl tert-butyl ether. One type of component (c) can be used alone, or two or more types of components (c) can be used in combination. The boiling point of component (c) at normal pressure is above 130°C, preferably above 145°C, and particularly preferably above 150°C. The boiling point of component (c) at normal pressure is lower than 250°C, preferably below 200°C. As described above, the boiling point of component (c) at normal pressure is above 130°C, but lower than 250°C. If the boiling point of component (c) at normal pressure is lower than 130°C, drying is performed near the injection nozzle, resulting in discharge failures such as clogging or deformation. In addition, since the volatilization rate in the waiting step described later is too high, component (c) may volatilize before the droplets of the curable composition (A) combine with each other, and the droplets of the curable composition may not combine. On the other hand, if the boiling point of component (c) at normal pressure is 250° C. or more, discharge failures such as clogging or deformation are improved. However, in the waiting step described later, the volatilization of the solvent (c) is insufficient, and component (c) may remain in the cured product of the curable composition (A).

[0225] Examples of the ether hydrocarbon solvents are as follows.

[0226] Ethylene glycol di-tert-butyl ether, diethylene glycol methyl tert-butyl ether, MFDG tBu (manufactured by NIPPON NYUKAZAI)

[0227] Examples of perfluorocarbon solvents are as follows.

[0228] FC-40, FC-43 (manufactured by 3M)

[0229] Examples of the fluorine-containing alcohol solvent are as follows.

[0230] 3-(Perfluorobutyl)propanol, 3-(Perfluorohexyl)propanol, 2,2,3,4,4,5,5-octafluoro-1,6-hexanediol

[0231] Examples of the ester-based fluorinated solvents are as follows.

[0232] 5H-octafluoropentanoic acid ethyl ester

[0233] Examples of the halogenated fluorinated solvents are as follows.

[0234] 2-(Perfluorobutyl)ethyl iodide, 2-(Perfluorohexyl)ethyl iodide, octafluoro-1,4-diiodobutane, dodecafluoro-1,6-diiodohexane, 1-bromoheptafluoropropane

[0235] Among the above solvents, ether hydrocarbon solvents, perfluorocarbon solvents, ester-based fluorinated solvents and halogenated fluorinated solvents are preferred.

[0236] Other preferred examples of the solvent are as follows.

[0237] Ethylene glycol di-tert-butyl ether, diethylene glycol methyl tert-butyl ether

[0238] In the present invention, if the surface tension of the curable composition in a state where the solvent (c) is removed is γ1 [mN / m], and the surface tension of the solvent (c) at 23 ° C is γ2 [mN / m], the curable composition is constructed so that γ1 is greater than γ2. In other words, when Δγ = γ1-γ2, the curable composition is constructed so that Δγ is greater than zero. More specifically, the solvent (c) is selected so that Δγ is greater than zero. If Δγ is greater than zero, in the waiting step described later, the diffusion of each droplet of the curable composition will be accelerated due to the Marangoni effect, and the droplets will quickly combine with each other to form a continuous liquid film. In addition, since the rapid diffusion of the droplets accelerates the volatilization of the solvent, the waiting step described later is completed in a short time, or the conditions of the baking step are relaxed or omitted. Δγ is preferably 0.1 or more (γ1-γ2>0.1 [mN / m]), particularly preferably 1.0 or more (γ1-γ2>1 [mN / m]), and further preferably 2.0 or more. Note that both γ1 and γ2 are surface tensions at normal pressure (1 atm).

[0239] In the present invention, a polymerizable compound having a boiling point of 80° C. or higher and lower than 250° C. under normal pressure can also be used as component (d). Examples of the polymerizable compound having a boiling point of 80° C. or higher and lower than 250° C. under normal pressure are as follows.

[0240] Cyclohexyl acrylate (198°C), benzyl acrylate (229°C), isobornyl acrylate (245°C), tetrahydrofurfuryl acrylate (202°C), trimethylcyclohexyl acrylate (232°C), isooctyl acrylate (217°C), n-octyl acrylate (228°C), ethoxyethyl acrylate (230°C), divinylbenzene (193°C), 1,3-diisopropenylbenzene (218°C), styrene (145°C) and α-methylstyrene (165°C).

[0241] In the present invention, when the total amount of the curable composition (A) is 100% by volume, the content of the solvent (c) is 5% by volume or more and 95% by volume or less, preferably 70% by volume or more and 85% by volume or less, and more preferably 70% by volume or more and 80% by volume or less. If the content of the solvent (c) is less than 5% by volume, a thin film cannot be obtained after the solvent (b) evaporates under the condition of obtaining a substantially continuous liquid film. In addition, if the content of the solvent (c) is greater than 95% by volume, even if the droplets are densely dripped by a spraying method, it is difficult to obtain a thick film after the solvent (d) evaporates.

[0242] <Component (d): Non-polymerizable compound>

[0243] In addition to the above-mentioned components (a) and (b), the curable composition (A) may also contain a non-polymerizable compound as a component (d). An example of component (d) is a compound that does not contain a polymerizable functional group such as a (meth)acryloyl group and does not have the ability to sense light having a predetermined wavelength and generate the previously described polymerization factor (free radical). Examples of non-polymerizable compounds are sensitizers, hydrogen donors, internal mold release agents, antioxidants, polymer components, and other additives. Component (d) may contain various types of the above-mentioned compounds.

[0244] The sensitizer is a compound added appropriately to promote the polymerization reaction and improve the reaction conversion rate. As the sensitizer, one type of compound may be used alone, or two or more types of compounds may be used by mixing.

[0245] An example of a sensitizer is a sensitizing dye. The sensitizing dye is a compound that is excited by absorbing light having a specific wavelength, and interacts with a photopolymerization initiator as component (b). The "interaction" mentioned here is energy transfer or electron transfer from the sensitizing dye in an excited state to the photopolymerization initiator as component (b). Examples of sensitizing dyes are as follows, but the sensitizing dyes are not limited to these examples.

[0246] Anthracene derivatives, anthraquinone derivatives, pyrene derivatives, perylene derivatives, carbazole derivatives, benzophenone derivatives, thioxanthone derivatives, flavonoid derivatives, coumarin derivatives, phenothiazine derivatives, camphorquinone derivatives, acridine dyes, thiopyrylium salt-based dyes, cyanine dyes, quinoline dyes, styrylquinoline dyes, ketocoumarin dyes, thioxanthenyl dyes, xanthenyl dyes, oxo alcohol-based dyes, cyanine dyes, rhodamine-based dyes and pyrylium salt-based dyes.

[0247] The hydrogen donor is a compound that reacts with the initiation radical generated from the photopolymerization initiator as component (b) or the radical at the end of polymerization growth and generates a radical having higher reactivity. When the photopolymerization initiator as component (b) is a photo radical generator, it is preferred to add the hydrogen donor.

[0248] Examples of the above-mentioned hydrogen donor are as follows, but the hydrogen donor is not limited to these examples.

[0249] Amine compounds such as n-butylamine, di-n-butylamine, tri-n-butylphosphine, allylthiourea, s-benzylisothiourea p-toluenesulfinate, triethylamine, diethylaminoethyl methacrylate, triethylenetetramine, 4,4'-bis(dialkylamino)benzophenone, N,N-dimethylaminoethyl benzoate, N,N-dimethylaminoisoamyl benzoate, 4-dimethylaminobenzoic acid amyl ester, triethanolamine and N-phenylglycine; and mercapto compounds such as 2-mercapto-N-phenylbenzimidazole and mercaptopropionate.

[0250] One type of hydrogen donor may be used alone, or two or more types of hydrogen donors may be used by mixing. The hydrogen donor may also function as a sensitizer.

[0251] In order to reduce the interfacial bonding force between mold and curable composition, i.e. reduce the demoulding force in demoulding step (described later), internal mold release agent can be added to curable composition. In this specification, "inside" refers to that before curable composition arrangement step, mold release agent is pre-added to curable composition. As internal mold release agent, surfactant can be used, such as, silicon-based surfactant, fluorine-based surfactant and hydrocarbon-based surfactant. However, in the present invention, as described later, the addition amount of fluorine-based surfactant is limited. Note that the internal mold release agent according to the present invention is non-polymerizable. One type of internal mold release agent can be used alone, or two or more types of internal mold release agents can be used in combination.

[0252] Fluorine-based surfactants include the following.

[0253] Polyoxyalkylene (eg polyethylene oxide or polypropylene oxide) adducts of alcohols having a perfluoroalkyl group and polyoxyalkylene (eg polyethylene oxide or polypropylene oxide) adducts of perfluoropolyethers.

[0254] Note that the fluorine-based surfactant may have a hydroxyl group, an alkoxy group, an alkyl group, an amino group, or a mercapto group in a part of the molecular structure (eg, a terminal group). An example is pentaethylene glycol mono1H,1H,2H,2H perfluorooctyl ether.

[0255] Commercially available products may also be used as the fluorine-based surfactant. Examples of commercially available products of the fluorine-based surfactant are as follows.

[0256] F-444, TF-2066, TF-2067 and TF-2068, and DEO-15 (abbreviation) (manufactured by DIC)

[0257] Fluorad FC-430 and FC-431 (manufactured by Sumitomo 3M) S-382 (manufactured by AGC); EFTOP EF-122A, 122B, 122C, EF-121, EF-126, EF-127, and MF-100 (manufactured by Tochem Products)

[0258] PF-636, PF-6320, PF-656 and PF-6520 (manufactured by OMNOVA Solutions) DS-401, DS-403 and DS-451 (manufactured by DAIKIN)

[0259] 250, 251, 222F and 208G (manufactured by NEOS).

[0260] The internal mold release agent may also be a hydrocarbon-based surfactant. The hydrocarbon-based surfactant includes an alkyl alcohol polyoxyalkylene adduct obtained by adding an alkylene oxide having 2 to 4 carbon atoms to an alkyl alcohol having 1 to 50 carbon atoms.

[0261] Examples of the alkyl alcohol polyoxyalkylene adducts are as follows.

[0262] Methanol ethylene oxide adduct, decyl alcohol ethylene oxide adduct, lauryl alcohol ethylene oxide adduct, hexyl alcohol ethylene oxide adduct, stearyl alcohol ethylene oxide adduct and stearyl alcohol-ethylene oxide / propylene oxide adduct.

[0263] Note that the terminal group of the alkyl alcohol polyoxyalkylene adduct is not limited to a hydroxyl group which can be prepared by simply adding polyoxyalkylene to an alkyl alcohol. The hydroxyl group may also be substituted with a polar functional group such as a carboxyl group, an amino group, a pyridyl group, a mercapto group or a silanol group, or with a hydrophobic group such as an alkyl group or an alkoxy group.

[0264] Examples of the polyoxyalkylenes are as follows.

[0265] Polyethylene glycol, polypropylene glycol, their mono- or dimethyl ethers, mono- or dioctyl ethers, mono- or dinonyl ethers and mono- or didecyl ethers, monoadipates, monooleates, monostearates and monosuccinates.

[0266] Commercially available products can also be used as the alkyl alcohol polyoxyalkylene adduct. Examples of commercially available products of the alkyl alcohol polyoxyalkylene adduct are as follows.

[0267] Polyoxyethylene methyl ether (methanol ethylene oxide adduct) (BLAUNON MP-400, MP-550 and MP-1000) manufactured by AOKIOIL INDUSTRIAL, polyoxyethylene decyl ether (decyl alcohol ethylene oxide adduct) (FINESURF D-1303, D-1305, D-1307 and D-1310) manufactured by AOKIOIL INDUSTRILD, lauryl alcohol polyoxyethylene ether (lauryl alcohol ethylene oxide adduct) (BLAUNON EL-1505) manufactured by AOKIOIL INDUSTRIAL, polyoxyethylene cetyl ether (cetyl alcohol ethylene oxide adduct) (BLAUNON CH-305 and CH-310) manufactured by AOKI OIL INDUSTRIAL, polyoxyethylene stearyl ether (stearyl alcohol ethylene oxide adduct) (BLAUNON SR-705, SR-707, SR-715, SR-720, SR-730 and SR-750), random polymerized polyoxyethylene polyoxypropylene stearyl ether (BLAUNON SA-50 / 50 1000R and SA-30 / 70 2000R) manufactured by AOKIOIL INDUSTRING, polyoxyethylene methyl ether manufactured by BASF A760E) and polyoxyethylene alkyl ether manufactured by KAO (EMULGEN series).

[0268] Commercially available products can also be used as polyoxyalkylenes. An example is an ethylene oxide / propylene oxide copolymer (Pluronic PE6400) manufactured by BASF.

[0269] Fluorine-based surfactants have excellent demoulding force reduction effects, so they are effective as internal release agents. The mixing ratio of component (d) other than fluorine-based surfactants in the curable composition (A) relative to the sum of component (a), component (b) and component (d) (i.e., the total mass of all components except solvent (c)) is preferably 0% by weight or more and 50% by weight or less. The mixing ratio of component (d) other than fluorine-based surfactants in the curable composition (A) relative to the total mass of all components except solvent (c) is more preferably 0.1% by weight or more and 50% by weight or less, and further preferably 0.1wt% or more and 20% by weight or less. When the mixing ratio of component (d) other than fluorine-based surfactants is set to 50% by weight or less, a cured film with a certain mechanical strength can be obtained.

[0270] <Temperature when mixing the curable composition>

[0271] When preparing the curable composition (A), at least component (a), component (b) and component (c) are mixed and dissolved under a predetermined temperature condition. More specifically, the predetermined temperature condition is 0° C. or higher and 100° C. or lower. Note that the same applies to the case where the curable composition (A) contains component (d).

[0272] <Viscosity of Curable Composition>

[0273] The curable composition (A) is a liquid. This is because in the arrangement step (described later), droplets of the curable composition (A) are discretely dropped on the substrate by a jetting method. At 23°C and 1atm, the viscosity of the curable composition (A) is 1.3mPa·s or more and 60mPa·s or less, preferably 3mPa·s or more and 30mPa·s or less, and further preferably 3mPa·s or more and 15mPa·s or less. If the viscosity of the curable composition (A) is less than 1.3mPa·s, the discharge performance of the droplets of the jetting method becomes unstable. In addition, if the viscosity of the curable composition (A) is greater than 60mPa·s, it is difficult to form droplets of a volume of about 1.0pL to 3.0pL, which is favorable in the present invention.

[0274] In the state after the solvent (c) has volatilized from the curable composition (A), that is, in the state in which the solvent (c) has been removed, the viscosity of the composition at 23°C and 1atm is 30mPa·s or more and 10000mPa·s or less. In the state in which the solvent (c) has been removed, the viscosity of the composition at 23°C and 1atm is preferably 90mPa·s or more and 2000mPa·s or less, for example, 120mPa·s or more and 1000mPa·s or less. In the state in which the solvent (c) has been removed, the viscosity of the composition at 23°C and 1atm is further preferably 200mPa·s or more and 500mPa·s or less. The composition in the state in which the solvent (c) has been removed is also expressed as a curable composition (A'). When the viscosity of the curable composition (A') at 23°C is set to 1000mPa·s or less, when the curable composition (A') is brought into contact with the mold, diffusion and filling are quickly completed. Therefore, the use of the curable composition (A) makes it possible to perform an imprint process with high throughput and suppress pattern defects caused by insufficient filling. In addition, when the viscosity of the curable composition (A') at 23°C is set to 30 mPa·s or more, it is possible to prevent the droplets of the curable composition from flowing unnecessarily. In addition, when the curable composition (A') is brought into contact with the mold, it is possible to suppress the curable composition from flowing out from the end of the mold.

[0275] <Surface Tension of Curable Composition>

[0276] At 23°C and 1 atm, the surface tension of the curable composition (A) in a state where the solvent (component (c)) is removed is 5 mN / m or more and 30 mN / m or less. At 23°C and 1 atm, the curable composition (A) in a state where the solvent (component (c)) is removed more preferably has a surface tension of 7 mN / m or more and 28 mN / m or less, and further preferably has a surface tension of 10 mN / m or more and 26 mN / m or less. In other words, the curable composition (A') preferably has a surface tension of 5 mN / m or more and 30 mN / m or less, more preferably has a surface tension of 7 mN / m or more and 28 mN / m or less, and further preferably has a surface tension of 10 mN / m or more and 28 mN / m or less. Note that when the surface tension is high, for example, 5 mN / m or more, capillary action works strongly, so when the curable composition (A) and the mold are in contact with each other, filling (diffusion and filling) is completed in a short time. Furthermore, when the surface tension is 30 mN / m or less, a cured film obtained by curing the curable composition has surface smoothness.

[0277] <Contact Angle of Curable Composition>

[0278] The contact angle of the curable composition (A) in the state where the solvent (component (c)) is removed relative to both the substrate surface and the mold surface is preferably 0 ° or more and 90 ° or less, and particularly preferably 0 ° or more and 10 ° or less. In other words, the contact angle of the curable composition (A ') is preferably 0 ° or more and 90 ° or less, and particularly preferably 0 ° or more and 10 ° or less. If the contact angle is greater than 90 °, capillary action acts in the pattern of the mold or in the gap between the substrate and the mold in the negative direction (the direction in which the contact interface between the mold and the curable composition contracts), and the mold may not be filled with the curable composition (A). When the contact angle is small, capillary action works strongly and the filling rate increases.

[0279] <Impurities Mixed in Curable Composition>

[0280] The curable composition (A) preferably contains as few impurities as possible. Note that impurities refer to components other than the above-mentioned components (as), (a), (b), (c) and (d). Therefore, the curable composition (A) is advantageously a composition obtained by a refining step. Such a refining step is preferably filtered using a filter.

[0281] As the filtration using a filter, it is advantageous to mix the above-mentioned components (a), component (b) and component (c), and by using a filter having a pore size of more than 0.001 μm and less than 5.0 μm to filter the mixture. When filtering using a filter, it is further advantageous to filter in multiple stages, or to repeat multiple filtrations (circulation filtration). It is also possible to refilter the liquid filtered by the filter, or to filter using a filter with different pore sizes. The example of the filter used for filtering is a filter made of, for example, polyethylene resin, polypropylene resin, fluororesin and nylon resin, but the filter is not particularly limited. Impurities such as particles mixed in the curable composition can be removed by the above-mentioned refining step. Therefore, it is possible to prevent the impurities mixed in the curable composition from causing pattern defects by forming undesirable inhomogeneities on the cured film obtained after the curing composition is cured.

[0282] Note that when using the curable composition (A) to manufacture a semiconductor integrated circuit, it is advantageous to avoid mixing impurities containing metal atoms (metal impurities) into the curable composition as much as possible so as not to hinder the operation of the product. The concentration of the metal impurities contained in the curable composition is preferably 10 ppm or less, and more preferably 100 ppb or less.

[0283] [Drip Components]

[0284] In the present specification, a member (dropping member) on which droplets of the curable composition (A) are discretely dropped is described as a substrate (mold base material) or a mold (master mold).

[0285] The mold substrate is made of, for example, quartz. The mold substrate can have an adhesive layer on the surface. However, the mold substrate is not limited to quartz. For example, the mold substrate can be freely selected from those materials known as semiconductor device substrates such as silicon, aluminum, titanium tungsten alloy, aluminum silicon alloy, aluminum copper silicon alloy, silicon oxide and silicon nitride. Note that it is preferred to process the surface of the mold substrate by a surface treatment such as silane coupling treatment, silazane treatment or organic film deposition, thereby improving the adhesion to the curable composition (A). The adhesive layer described in Japanese Patent Laid-Open No. 2009-503139 can be used as an example of an organic film deposited with surface treatment.

[0286] [First Pattern Formation Method]

[0287] Will refer to Figures 1A to 1GThe first pattern forming method according to the present invention is described. In the first pattern forming method, the member on which the droplets of the curable composition (A) are discretely dripped is a mold substrate. The cured film formed by the present invention is preferably a film with a pattern having a size of more than 1nm and less than 10mm, more preferably a film with a size of more than 10nm but less than 100μm. Generally, the film forming method of a film having a pattern (concave-convex structure) of nanometer size (more than 1nm and less than 100nm) is called a photoembossing method. The film forming method of the present invention forms a film of a curable composition in the space between a mold substrate and a master mold by using a photoembossing method. However, the curable composition can also be cured by another energy (for example, heat or electromagnetic waves). In addition, the film forming method according to the present invention can be performed as a method for forming a film with a pattern, that is, a pattern forming method, or can be performed as a method for forming a film without a pattern (for example, a flat film), that is, a flat film forming method.

[0288] The following will describe an example in which the film forming method according to the present invention is applied to the first pattern forming method. The first pattern forming method includes, for example, a preparation step, an arrangement step, a waiting step, a contact step, a curing step, and a demoulding step. The preparation step is a step of preparing the bottom layer. The arrangement step is a step of discretely arranging droplets of the curable composition (A) on the bottom layer. The waiting step is a step of waiting until the droplets of the curable composition (A) are combined with each other and the solvent (c) is volatilized. The contact step is a step of contacting the curable composition (A or A'), preferably the curable composition (A') with the master mold. The curing step is a step of curing the curable composition (A or A'), preferably the curable composition (A'). The demoulding step is a step of separating the master mold from the cured film of the curable composition (A or A'). The arrangement step is performed after the preparation step, the waiting step is performed after the arrangement step, the contact step is performed after the waiting step, the curing step is performed after the contact step, and the demoulding step is performed after the curing step.

[0289] <Layout steps>

[0290] In the layout step, Figure 1A As schematically shown in FIG. 1 , droplets 102 of the curable composition (A) are discretely arranged on a mold substrate 101 .

[0291] The spraying method is particularly preferred as a method for arranging the droplets 102 of the curable composition (A) on the mold substrate. The droplets 102 of the curable composition (A) are densely arranged on the area of ​​the mold substrate 101 facing the area where the concave portions forming the pattern of the master mold 106 are densely present. In addition, the droplets 102 of the curable composition (A) are sparsely arranged on the area of ​​the mold substrate 101 facing the area where the concave portions forming the pattern of the master mold 106 are sparsely present. Therefore, regardless of whether the pattern of the master mold 106 is dense or sparse, the film (residual film) of the curable composition (A) (described later) formed on the mold substrate 101 can be controlled to a uniform thickness.

[0292] In order to define the volume of the curable composition (A) to be arranged on the mold substrate, an index called average liquid film thickness is defined. The average liquid film thickness is a value obtained by dividing the volume of the curable composition (A) (excluding solvent (c)) arranged in the arrangement step by the area of ​​the film forming region of the master mold. The volume of the cured product or cured film of the curable composition (A) (excluding solvent (c)) is the sum of the droplet volumes of the curable composition (A) after the solvent (c) volatilizes. According to this definition, even if the surface of the mold substrate has a concave-convex pattern, the average liquid film thickness can be defined without considering the concave-convex state.

[0293] <Waiting Step>

[0294] In the present invention, a waiting step is provided after the arrangement step and before the contact step (between the arrangement step and the contact step). Here, the value obtained by dividing the total volume of the droplets of the curable composition (A) dripped in the primary pattern formation by the total area of ​​the region (film formation region) where the pattern is formed by the primary pattern formation is defined as the average film thickness. In the waiting step, the droplets 102 of the curable composition (A) are spread on the mold substrate 101, as shown in FIG. Figure 1B The entire pattern forming area of ​​the mold substrate 101 is covered with the curable composition (A). If the average film thickness is 130nm or more, as Figure 1C As schematically shown in FIG. 1 , the droplets of the curable composition (A) are combined with each other on the mold substrate to form a substantially continuous liquid film 103. If the average film thickness is 150 nm or more, the surface of the liquid film 103 is flat. 2 The liquid droplets 102 of the curable composition (A) having a volume of 1.0 pL or more can be arranged at a density of 150 / mm to obtain a liquid film 103 having an average film thickness of 130 nm or more. 2By arranging the droplets 102 of the curable composition (A) having a volume of 1.0 pL or more at the above density, a liquid film 103 having an average film thickness of 150 nm or more can be obtained. Note that in this embodiment, the average film thickness is preferably 10 μm or less, and particularly preferably 1 μm or less. If the average film thickness is greater than 10 μm, the stability of the pattern shape of the replica mold is low.

[0295] Will refer to FIG. 2A to FIG. 2D Explain the flow behavior of the droplets of the curable composition (A) arranged on the mold substrate during the waiting step. Figure 2A As shown, droplets of the curable composition (A) are discretely arranged on the mold substrate, such as Figure 2B As shown in FIG. 1 , each droplet will gradually spread on the mold substrate. Then, as Figure 2C As shown, the droplets of curable composition (A) on the mold substrate begin to combine with each other and Figure 2D As shown, a continuous liquid film is formed (a state in which the surface of the mold substrate is covered with the curable composition (A) and no exposed surface is left). Figure 2D The state of the curable composition (A) shown is referred to as a "practically continuous liquid film".

[0296] In addition, in the waiting step, if Figure 1D Schematically, the solvent 105 (solvent (c)) contained in the liquid film 103 is volatilized. Assuming that the total weight of components other than the solvent (c) is 100% by volume, the residual amount of the solvent (c) in the liquid film 104 after the waiting step (for example, in the contact step) is preferably 10% by volume or less. If the residual amount of the solvent (c) is greater than 10% by volume, the mechanical properties of the cured film may be deteriorated.

[0297] In the waiting step, in order to accelerate the volatilization of the solvent (c), a baking step of heating the mold substrate 101 and the curable composition (A) may be performed, or the atmosphere around the mold substrate 101 may be ventilated. The heating is performed at a temperature of, for example, 30° C. to 200° C., preferably 80° C. to 150° C., particularly preferably 90° C. to 110° C. The heating time may be 10 seconds to 600 seconds. The baking step may be performed by using a known heater such as an electric furnace or an oven.

[0298] The waiting step is, for example, 0.1 seconds to 600 seconds, preferably 10 seconds to 300 seconds. If the waiting step is shorter than 0.1 seconds, the combination of the droplets of the curable composition (A) becomes insufficient, so a continuous liquid film is not actually formed. If the waiting step exceeds 600 seconds, productivity will decrease. Therefore, in order to suppress the reduction in productivity, the mold substrate that is completely processed in the arrangement step can also be moved to the waiting step in sequence, the waiting step is carried out in parallel with a plurality of mold substrates, and the mold substrate that is completely processed in the waiting step is moved to the contact step in sequence. Note that in the related art, before forming an actual continuous liquid film, it is theoretically necessary to have several thousand seconds to tens of thousands of seconds. However, in practice, because the diffusion of the droplets of the curable composition stagnates due to the influence of volatilization, it is impossible to form a continuous liquid film.

[0299] In the waiting step, when the solvent (c) evaporates, a substantially continuous liquid film 104 of the composition made of the component (as), the component (af), the component (a), the component (b), and the component (d), namely, the curable composition (A'), remains. The average film thickness of the substantially continuous liquid film 104 of the curable composition (A) from which the solvent (c) evaporates (is removed), namely, the curable composition (A'), is smaller than the average film thickness of the liquid film 103 by the amount of the evaporated solvent (c). The state in which the pattern forming area of ​​the mold substrate 101 is completely covered by the substantially continuous liquid film 104 of the curable composition (A') is maintained.

[0300] <Contact Steps>

[0301] In the contacting step, Figure 1E Schematically shown in FIG, the curable composition (A) from which the solvent (c) is removed, that is, the substantially continuous liquid film 104 of the curable composition (A') is brought into contact with the master mold 106. The contact step includes a step of changing the state in which the curable composition (A') and the master mold 106 are not in contact with each other to a state in which they are in contact with each other, and a step of maintaining the state in which they are in contact with each other. Thus, the liquid of the curable composition (A') is filled into the recesses of the fine pattern on the surface of the master mold 106, and the liquid forms a liquid film filled in the fine pattern of the master mold 106.

[0302] In the waiting step, since the solvent (c) is removed from the curable composition (A) and a substantially continuous liquid film 104 of the curable composition (A') is formed, the volume of gas trapped between the mother mold 106 and the mold substrate 101 is small. Therefore, the diffusion of the curable composition (A') in the contacting step is completed quickly. Figure 4 A comparison (difference) between a contact step in the related art disclosed in Japanese Patent No. 6584578 and the like and a contact step according to the present invention is shown.

[0303] If the diffusion and filling of the curable composition (A') are completed quickly in the contact step, the time (the time required for the contact step) in which the master mold 106 is in contact with the curable composition (A') can be shortened. Since shortening the time required for the contact step shortens the time required for pattern formation (film formation), productivity is improved. The contact step is preferably 0.1 seconds or more and 3 seconds or less, and particularly preferably 0.1 seconds or more and 1 second or less. If the contact step is shorter than 0.1 seconds, diffusion and filling become insufficient, and therefore many defects referred to as incomplete filling defects tend to occur.

[0304] If the curing step includes a light irradiation step, it is preferable to use a mold made of a light-transmitting material as the master mold 106. Favorable examples of the type of material forming the master mold 106 are glass, quartz, PMMA, a light-transmitting resin such as a polycarbonate resin, a transparent metal deposition film, a soft film such as polydimethylsiloxane, a photocurable film, and a metal film. Note that when a light-transmitting resin is used as a material forming the master mold 106, a resin that is insoluble in the components contained in the curable composition is selected. Quartz is suitable as a material for forming the master mold 106 because it has a small thermal expansion coefficient and a small pattern deformation.

[0305] The pattern formed on the surface of master mold 106 has a height of, for example, more than 4nm and less than 200nm. As the pattern height of master mold 106 decreases, the force that mold is separated from the cured film of curable composition, i.e. the demoulding force in the demoulding step, can be reduced. Therefore, the quantity of demoulding defects retained in master mold 106 due to the pattern of curable composition being torn can be reduced. In addition, in some cases, when master mold 106 is demoulded, the pattern of curable composition can be elastically deformed due to impact, and adjacent pattern elements can contact each other and adhere to each other or damage each other. Note that, in order to avoid these problems, it is advantageous to make the height of pattern elements about less than twice of pattern element width (making aspect ratio less than 2). On the other hand, if the height of pattern elements is too small, the machining accuracy of mold base material 101 can be reduced.

[0306] Before the contacting step is performed, the master mold 106 may also be subjected to a surface treatment to improve the releasability of the master mold 106 relative to the curable composition (A). An example of such a surface treatment is to form a release agent layer by coating the surface of the master mold 106 with a release agent. Examples of the release agent applied to the surface of the master mold 106 are silicon-based release agents, fluorine-based release agents, hydrocarbon-based release agents, polyethylene-based release agents, polypropylene-based release agents, paraffin-based release agents, lignite-based release agents, and carnauba-based release agents. Commercially available coating-type release agents, such as those manufactured by Daikin, may also be appropriately used. DSX. Note that one type of releasing agent may be used alone, or two or more types of releasing agents may be used simultaneously. Among the above-mentioned releasing agents, fluorine-based and hydrocarbon-based releasing agents are particularly advantageous.

[0307] In the contact step, the pressure applied to the curable composition (A) when the master mold 106 is brought into contact with the curable composition (A) is not particularly limited, and is, for example, 0 MPa or more and 100 MPa or less. Note that the pressure applied to the curable composition (A) when the master mold 106 is brought into contact with the curable composition (A) is preferably 0 MPa or more and 50 MPa or less. In addition, the pressure applied to the curable composition (A) when the master mold 106 is brought into contact with the curable composition (A) is more preferably 0 MPa or more and 30 MPa or less, and further preferably 0 MPa or more and 20 MPa or less.

[0308] The contact step can be carried out in any one of a normal air atmosphere, a reduced pressure atmosphere and an inert gas atmosphere. However, a reduced pressure atmosphere or an inert gas atmosphere is advantageous because the effect of oxygen or water on the curing reaction can be prevented. Practical examples of inert gases used when the contact step is carried out in an inert gas atmosphere are nitrogen, carbon dioxide, helium, argon, various freon gases and gas mixtures thereof. When the contact step is carried out in a specific gas atmosphere including a normal air atmosphere, a favorable pressure is 0.0001 atm or more and 10 atm or less.

[0309] <Curing Step>

[0310] During the curing step, Figure 1F Schematically shown in FIG, the curable composition (A') is cured by being irradiated with the irradiation light 107 used as the curing energy, thereby forming a cured film. In the curing step, for example, the curable composition (A') is irradiated with the irradiation light 107 through the master mold 106. More specifically, the curable composition (A') filled in the fine pattern of the master mold 106 is irradiated with the irradiation light 107 through the master mold 106. Therefore, the curable composition (A') filled in the fine pattern of the master mold 106 is cured, and a cured film 108 having a pattern is formed.

[0311] The irradiation light 107 is selected according to the sensitivity wavelength of the curable composition (A). More specifically, the irradiation light 107 is appropriately selected from ultraviolet light, X-rays and electron beams each having a wavelength of more than 150nm and less than 400nm. Note that the irradiation light 107 is particularly preferably ultraviolet light. This is because many commercially available compounds as curing aids are sensitive to ultraviolet light. Examples of light sources that emit ultraviolet light are high-pressure mercury lamps, ultra-high-pressure mercury lamps, low-pressure mercury lamps, deep ultraviolet lamps, carbon arc lamps, metal halide lamps, xenon lamps, KrF excimer lasers, ArF excimer lasers and F2 lasers. Note that ultra-high-pressure mercury lamps are particularly advantageous as light sources that emit ultraviolet light. One light source or multiple light sources can be used. Light can be emitted to the entire area of ​​the curable composition (A) filled in the fine pattern of the master mold, or (by limiting the area) only to a portion of its area. It is also possible to emit light to the entire area of ​​the mold substrate intermittently for many times, or to emit light to the entire area of ​​the mold substrate continuously. Furthermore, in the first irradiation process, a first region of the mold substrate may be irradiated with light, and in the second irradiation process, a second region different from the first region of the mold substrate may be irradiated with light.

[0312] <Demolding Step>

[0313] In the demoulding step, Figure 1G As schematically shown in FIG. 1 , the master mold 106 is separated from the cured film 108. By separating the cured film 108 having a pattern and the master mold 106 from each other, the cured film 108 having a pattern formed by inverting the fine pattern of the master mold 106 is obtained in an independent state on the mold base material. Here, the cured film remains in the concave portion of the cured film 108 having a pattern corresponding to the pattern of the master mold 106. This film is referred to as a residual film.

[0314] The method of detaching the master mold 106 from the cured film 108 having a pattern may be any method as long as the method does not physically damage the portion of the cured film 108 having a pattern during the detachment process, and various conditions, etc. are not particularly limited. For example, the mold base 101 may be fixed and the master mold 106 may be moved away from the mold base 101. The master mold 106 may also be fixed and the mold base 101 may be moved away from the master mold 106. In addition, the master mold 106 may be detached from the cured film 108 having a pattern by moving both the master mold 106 and the mold base 101 in completely opposite directions.

[0315] <repeat>

[0316] A series of steps (manufacturing process) having the above steps from the arrangement step to the demolding step in this order makes it possible to obtain a cured film having a desired concavo-convex pattern shape (a pattern shape conforming to the concavo-convex shape of the mother mold 106) at a desired position.

[0317] In the first pattern forming method, the repetition unit (shot) from the arrangement step to the demolding step can be repeated multiple times on the same mold substrate, and the cured film 108 having multiple desired patterns at desired positions of the mold substrate can be obtained.

[0318] [Second Pattern Formation Method]

[0319] Will refer to Figures 3A to 3G The second pattern forming method according to the present invention is described. In the second pattern forming method, the member on which droplets of the curable composition (A) are discretely dropped is a master mold.

[0320] The following describes an example in which the film forming method according to the present invention is applied to the second pattern forming method. For example, the second pattern forming method includes: a preparation step, an arrangement step, a waiting step, a contact step, a curing step, and a demolding step. The arrangement step is performed after the preparation step, the waiting step is performed after the arrangement step, the contact step is performed after the waiting step, the curing step is performed after the contact step, and the demolding step is performed after the curing step.

[0321] <Layout steps>

[0322] In the layout step, Figure 3A As schematically shown in FIG. 1 , droplets 102 of the curable composition (A) are discretely arranged on a master mold 106 .

[0323] The jetting method is particularly preferred as a method of arranging the droplets 102 of the curable composition (A) on the master mold. The droplets 102 of the curable composition (A) are densely arranged on the region where the concave portions forming the pattern of the master mold 106 are densely present, and the droplets 102 of the curable composition (A) are sparsely arranged on the region where the concave portions forming the pattern of the master mold 106 are sparsely present. Therefore, regardless of whether the pattern of the master mold 106 is dense or sparse, the film (residual film) of the curable composition (A) (described later) formed on the mold base material 101 is controlled to be uniform in thickness.

[0324] In order to define the volume of the curable composition (A) to be arranged on the master mold, an index called the average liquid film thickness is defined. As described above, the average liquid film thickness is a value obtained by dividing the volume of the curable composition (A) (excluding solvent (c)) arranged in the arrangement step by the area of ​​the film forming region of the master mold. The volume of the cured product or cured film of the curable composition (A) (excluding solvent (c)) is the sum of the droplet volumes of the curable composition (A) after the volatilization of the solvent (c). According to this definition, even if the surface of the mold substrate has a concave-convex pattern, the average liquid film thickness can be defined regardless of the concave-convex state.

[0325] <Waiting Step>

[0326] In the present invention, a waiting step is provided after the arranging step and before the contacting step (between the arranging step and the contacting step). Here, as described above, the value obtained by dividing the total volume of the droplets of the curable composition (A) dripped in one pattern formation by the total area of ​​the region (film formation region) patterned by the one pattern formation is defined as the average film thickness. In the waiting step, as Figure 3B As schematically shown in FIG. 1 , a droplet 102 of the curable composition (A) spreads on the master mold 106. The entire pattern forming area of ​​the master mold 106 is covered with the curable composition (A). Figure 3C As schematically shown in , the droplets of the curable composition (A) are combined with each other on the master mold, and form a substantially continuous liquid film 103. If the average film thickness is 150 nm or more, the surface of the liquid film 103 is flat.

[0327] The flow behavior of the droplets of the curable composition (A) arranged on the master mold during the waiting step is similar to that of the reference FIG. 2A to FIG. 2D The described flow behavior of the droplets of the curable composition (A) arranged on the mold substrate during the waiting step is the same. More specifically, the "mold substrate" only needs to be replaced with "mother mold", and its detailed description will be omitted here.

[0328] In addition, in the waiting step, if Figure 3D , the solvent 105 (solvent (c)) contained in the liquid film 103 is volatilized. Assuming that the total weight of the components other than the solvent (c) is 100% by volume, the residual amount of the solvent (c) in the liquid film 104 after the waiting step (for example, in the contact step) is preferably 10% by volume or less. If the residual amount of the solvent (c) is greater than 10% by volume, the mechanical properties of the cured film may be deteriorated.

[0329] In the waiting step, in order to accelerate the volatilization of the solvent (c), a baking step of heating the master mold 106 and the curable composition (A) or ventilating the atmosphere around the master mold 106 may be performed. The heating is performed at a temperature of, for example, 30° C. to 200° C., preferably 80° C. to 150° C., particularly preferably 90° C. to 110° C. The heating time may be 10 seconds to 600 seconds. The baking step may be performed by using a known heater such as an electric furnace or an oven.

[0330] The waiting step is, for example, 0.1 to 600 seconds, preferably 10 to 300 seconds. If the waiting step is shorter than 0.1 seconds, the combination of the droplets of the curable composition (A) becomes insufficient, so that a substantially continuous liquid film is not formed. If the waiting step exceeds 600 seconds, productivity will decrease. Therefore, in order to suppress the reduction in productivity, the master mold that is completely processed in the arrangement step can also be moved to the waiting step in sequence, the waiting step is performed in parallel with a plurality of master molds, and the master mold that is completely processed in the waiting step is moved to the contact step in sequence.

[0331] In the waiting step, when the solvent (c) evaporates, a substantially continuous liquid film 104 of the composition made of the component (as), the component (af), the component (a), the component (b), and the component (d), i.e., the curable composition (A'), is retained. The average film thickness of the substantially continuous liquid film 104 of the curable composition (A) from which the solvent (c) evaporates (is removed), i.e., the curable composition (A'), is smaller than the average film thickness of the liquid film 103 by the amount of the evaporated solvent (c). The state in which the pattern forming area of ​​the master mold 106 is completely covered by the substantially continuous liquid film 104 of the curable composition (A') is maintained.

[0332] <Contact Steps>

[0333] In the contacting step, Figure 3E Schematically shown in FIG. 1 , a substantially continuous liquid film 104 of the curable composition (A) from which the solvent (c) has been removed, i.e., the curable composition (A'), is brought into contact with the mold base material 101. The contact step includes: a step of changing the state in which the curable composition (A') and the mold base material 101 are not in contact with each other to a state in which they are in contact with each other, and a step of maintaining the state in which they are in contact with each other.

[0334] In the waiting step, since the solvent (c) is removed from the curable composition (A) and a substantially continuous liquid film 104 of the curable composition (A') is formed, the volume of the gas trapped between the mother mold 106 and the mold substrate 101 is small. Therefore, the diffusion of the curable composition (A') in the contacting step is completed quickly.

[0335] If the curing step includes a light irradiation step, it is preferable to use a substrate made of a light-transmitting material as the mold substrate 101. Favorable examples of the type of material forming the mold substrate 101 are glass, quartz, PMMA, a light-transmitting resin such as a polycarbonate resin, a transparent metal deposition film, a soft film such as polydimethylsiloxane, a photocurable film, and a metal film. Note that when a light-transmitting resin is used as a material forming the mold substrate 101, a resin that is insoluble in the components contained in the curable composition is selected. Quartz is suitable as a material for forming the mold substrate 101 because it has a small thermal expansion coefficient and a small pattern deformation.

[0336] In the contact step, the pressure applied to the curable composition (A) when the mold base material 101 is in contact with the curable composition (A) is not particularly limited, for example, 0 MPa or more and 100 MPa or less. Note that when the mold base material 101 is in contact with the curable composition (A), the pressure applied to the curable composition (A) is preferably 0 MPa or more and 50 MPa or less. In addition, when the mold base material 101 is in contact with the curable composition (A), the pressure applied to the curable composition (A) is more preferably 0 MPa or more and 30 MPa or less, and more preferably 0 MPa or more and 20 MPa or less.

[0337] <Curing Step>

[0338] During the curing step, Figure 3F Schematically shown in FIG. 1 , the curable composition (A') is cured by being irradiated with the irradiation light 107 used as the curing energy, thereby forming a cured film. In the curing step, for example, the curable composition (A') is irradiated with the irradiation light 107 through the mold base material 101. More specifically, the curable composition (A') filled in the fine pattern of the master mold 106 is irradiated with the irradiation light 107 through the mold base material 101. Therefore, the curable composition (A') filled in the fine pattern of the master mold 106 is cured, and a cured film 108 having a pattern is formed.

[0339] In the irradiation step, light may be emitted to the entire area of ​​the curable composition (A) filled in the fine pattern of the master mold, or (by limiting the area) only to a partial area thereof. It is also possible to emit light to the entire area of ​​the master mold intermittently multiple times, or to emit light to the entire area of ​​the master mold continuously. In addition, in the first irradiation process, the first area of ​​the master mold may be irradiated with light, and in the second irradiation process, the second area of ​​the master mold different from the first area may be irradiated with light.

[0340] <Demolding Step>

[0341] In the demoulding step, Figure 3G , the mother mold 106 is separated from the cured film 108. By separating the cured film 108 having a pattern and the mother mold 106 from each other, the cured film 108 having a pattern formed by inverting the fine pattern of the mother mold 106 is obtained in an independent state on the mold base material. Here, the cured film, that is, the residual film remains in the concave portion of the cured film 108 having a pattern corresponding to the pattern of the mother mold 106.

[0342] The method of detaching the master mold 106 from the cured film 108 having a pattern may be any method as long as the method does not physically damage the portion of the cured film 108 having a pattern during the detachment process, and various conditions, etc. are not particularly limited. For example, the mold base 101 may be fixed and the master mold 106 may be moved away from the mold base 101. The master mold 106 may also be fixed and the mold base 101 may be moved away from the master mold 106. In addition, the master mold 106 may be detached from the cured film 108 having a pattern by moving both the master mold 106 and the mold base 101 in completely opposite directions.

[0343] If the glass transition temperature of the curable composition is much higher than the temperature during demolding, the cured product during demolding exhibits a strong glass state, i.e., high mechanical strength, and therefore, pattern collapse or damage caused by the impact of demolding hardly occurs. Therefore, when the demolding step is performed at room temperature, the glass transition temperature of the cured product is preferably 70°C or higher, more preferably 100°C or higher, and particularly preferably 150°C or higher.

[0344] A method for measuring using differential scanning calorimetry (DSC) or a dynamic viscoelasticity measuring device can be applied as a method for measuring the glass transition temperature of a cured product. For example, the case of measuring the glass transition temperature using DSC will be studied. In this case, obtain: a straight line obtained by extending the baseline of the DSC curve on the low temperature side (the portion of the DSC curve in the temperature region where neither transformation nor reaction occurs in the sample) to the high temperature side, and a tangent drawn at the point where the gradient of the curve of the step change portion of the glass transition is the largest. The inferred glass transition starting temperature (Tig) is obtained according to the intersection of the straight line and the tangent, and the temperature can be obtained as the glass transition temperature. STA-6000 (manufactured by Perkin-Eimer) and the like can be used as the main device. On the other hand, when the glass transition temperature is measured using a dynamic viscoelasticity measuring device, the temperature at which the loss sine (tan δ) of the cured product is the largest is defined as the glass transition temperature. MCR301 (manufactured by Anton Paar) and the like can be used as the main device for measuring dynamic viscoelasticity.

[0345] [Example]

[0346] More practical examples will be explained to supplement the above-described embodiments.

[0347] <Conditions for obtaining a substantially continuous liquid film>

[0348] Droplets of a curable composition (A) having a surface tension of 24 mN / m, a viscosity of 30 mPa·s, and a volume of 1 pL were dropped (arranged) in a square array at predetermined intervals on a flat substrate (mold substrate). The curable composition was calculated by numerical calculation based on the Navier-Stokes equation.

[0349] The diffusion behavior of each droplet of (A) on the substrate is obtained by the thin film approximation of the free surface (lubrication theory). Table 1 below shows the film thickness at the center of the drop position (the thickest part of the liquid film on the substrate) and the film thickness at the center of the square formed by four droplets arranged in a square (the thinnest part of the liquid film on the substrate) after 300 seconds from the droplet of the curable composition (A). Note that it is assumed that the contact angle of the droplet of the curable composition (A) relative to the substrate is 0°, and the volatilization of the solvent (c) during 300 seconds from the droplet of the curable composition (A) can be ignored.

[0350] [Table 1]

[0351]

[0352] Referring to Table 1, in Examples 1 to 5 having an average film thickness of 130 nm or more, it was found that the entire area of ​​the substrate was covered with the curable composition (A). In addition, in Examples 1 to 3 having an average film thickness of 150 nm or more, it was found that a flat liquid film having a difference of substantially 0 nm between the thickness of the thickest portion and the thickness of the thinnest portion was formed.

[0353] <Controllability check of average film thickness>

[0354] Both the droplet volume and the square array spacing of the curable composition (A) can be changed, but as mentioned above, even in the area where the liquid film thickness is the smallest, the liquid film thickness before the solvent (c) evaporates is 130nm. Calculate the thickness of the liquid film retained after the solvent (c) evaporates from the state where a practically continuous liquid film is formed. Assuming that the minimum value of the square array spacing of the droplets of the curable composition (A) dripped onto the substrate is 35μm, calculate the maximum value of the thickness before contact with the mold (mother mold). As mentioned above, the minimum value of the liquid film thickness before the solvent (c) that forms a practically continuous liquid film evaporates is calculated to be 130nm. Therefore, the minimum value of the thickness of the liquid film before contact with the mold can be calculated by the main component concentration (volume %) × 130nm. Here, the main component concentration (volume %) is the value obtained by subtracting the volume % of the solvent (c) from 100 volume %. The case where the volume of the droplet of the curable composition (A) was 1.0 pL is shown in Table 2 below, and the case where the volume of the droplet of the curable composition (A) was 3.0 pL is shown in Table 3 below.

[0355] [Table 2]

[0356] Average residual film thickness at a droplet volume of 1.0 pL of the curable composition (A)

[0357]

[0358] [Table 3]

[0359] Average residual film thickness at a droplet volume of 3.0 pL of the curable composition (A)

[0360]

[0361] For example, in the photolithography step for manufacturing semiconductor devices, the film thickness required for film formation including pattern formation (or planarization) is 30 nm or more and 200 nm or less. Referring to Tables 2 and 3, if the main component concentration is 10% by volume or more, a film (thick film) with a thickness of 200 nm or more can be formed. If the main component concentration is 20% by volume or less, a film (thin film) with a thickness of 30 nm or less can be formed.

[0362] <Evaluation of ejection performance and filling performance>

[0363] According to Table 4 below, the curable composition (A) was mixed so that the total weight of component (as), component (a), component (b) and component (c) was 100 wt%. In addition, the curable composition (A) was mixed without using component (a) and component (c). Table 5 below shows the results of measuring the viscosity of the curable composition (A) at 23°C. Please note that the abbreviations in Table 4 are as follows.

[0364] “Component (as)”

[0365] TM-0701T: 3-Methacryloxypropyl tris(trimethylsiloxy)silane (manufactured by JNC)

[0366] AC-SQ TA-100: Silsesquioxane derivative having an acrylate group (manufactured by TOAGOSEI)

[0367] "Component (af)"

[0368] Viscosity 8F: 1H, 1H, 5H octafluoropentyl acrylate (manufactured by Osaka Organic Chemical Industry)

[0369] “Component (a)”

[0370] IBXA: Isobornyl acrylate (manufactured by Osaka Organic Chemical Industry)

[0371] DCP-A: dihydroxymethyl tricyclodecane diacrylate (manufactured by KYOEISHA CHEMICAL) "component (b)"

[0372] Omnirad 819: Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (manufactured by IGM Resin)

[0373] “Component (c)”

[0374] tBuG-Bu: Ethylene glycol di-tert-butyl ether (manufactured by NIPPON NYUKAZAI) (boiling point: 165°C)

[0375] MDG tBu: Diethylene glycol methyl tert-butyl ether (manufactured by NIPPON NYUKAZAI) (boiling point: 185°C)

[0376] MFDG tBu: 3,10,12,12-Tetramethyl-2,5,8,11-tetraoxytridecane (manufactured by NIPPON NYUKAZAI) (boiling point: 201° C.)

[0377] EOFP: 5H-ethyloctafluoropentanoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) (boiling point: 142° C.) PFEI: 2-perfluorohexylethyl iodide (manufactured by DAIKIN) (boiling point: 180° C.)

[0378] PGMEA: Propylene glycol monomethyl ether acetate (manufactured by KANTO CHEMICAL) (boiling point: 146°C)

[0379] 2-Trifluoromethyl-3-ethoxydodecafluorohexane (manufactured by FUJIFILM Wako Pure Chemical) (boiling point: 130° C.)

[0380] [Table 4]

[0381]

[0382]

[0383]

[0384]

[0385] [Table 5]

[0386]

[0387]

[0388] <Evaluation of jet discharge velocity>

[0389] In order to evaluate the ejection discharge speed, a commercially available industrial material printer DMP-2850 (manufactured by FUJIFILM) was used. Each curable composition of Examples 12 to 29 and Comparative Examples 4 to 6 shown in Table 4 was filled into a box (1 pL). The droplet discharge state was observed by an internal discharge observation camera, and the ejection discharge speed was evaluated based on the following evaluation criteria.

[0390] (Evaluation Criteria)

[0391] AAA: At a discharge speed (flying speed) of 6 m / s or more, no deviation (deformation) of the landing position was observed at all.

[0392] AA: At discharge velocities above 6 m / s, very slight deviations in the landing position were observed without practical effect.

[0393] A: At discharge speeds above 4 m / s, very slight deviations in the landing position were observed without practical impact.

[0394] B: No discharge occurs.

[0395] <Evaluation of intermittent discharge performance of injection>

[0396] In order to evaluate the intermittent discharge performance of the jet, a commercially available industrial material printer DMP-2850 (manufactured by FUJIFILM) was used. Each curable composition of Examples 12 to 29 and Comparative Examples 4 to 6 shown in Table 4 was filled into a box (1 pL). Droplets were discharged from all (12) nozzles for 1 second at a frequency of 40 kHz. After a predetermined rest period, a droplet was discharged from each nozzle, and its state was observed by an internal discharge observation camera, and the intermittent discharge performance of the jet was evaluated based on the following evaluation criteria.

[0397] (Evaluation Criteria)

[0398] AAA: Even after a rest period of 10 seconds, more than half of the nozzles were able to discharge droplets.

[0399] AA: Even after a rest period of 5 seconds, more than half of the nozzles were able to discharge droplets.

[0400] A: Even after a 3-second rest period, more than half of the nozzles were able to discharge droplets.

[0401] B: After a rest period of 3 seconds, more than half of the nozzles failed to discharge droplets.

[0402] <Evaluation of filling performance>

[0403] Under the condition that the liquid film thickness before the solvent (c) volatilized was 130 nm, each curable composition (A) of Examples 12 to 29 and Comparative Examples 4 to 6 shown in Table 4 was discretely dropped (arranged) on a silicon substrate. The time until a substantially continuous liquid film was formed was measured, and the filling performance was evaluated based on the following evaluation criteria.

[0404] (Evaluation Criteria)

[0405] AAA: A virtually continuous liquid film is formed in less than 100 seconds.

[0406] AA: A substantially continuous liquid film is formed within a time period of 100 seconds or more and less than 200 seconds.

[0407] A: A substantially continuous liquid film is formed within a period of 200 seconds or more and less than 300 seconds.

[0408] B: Even after 300 seconds, a substantially continuous liquid film was not formed.

[0409] Table 6 shows the evaluation results.

[0410]

[0411]

[0412] It was found that if the viscosity of the curable composition at 23° C. is 1.3 mPa·s or more and 60 mPa·s or less, the ejection discharge is excellent, and the viscosity is preferably 5 mPa·s or more and 30 mPa·s or less, more preferably 5 mPa·s or more and 15 mPa·s or less.

[0413] It was found that if the boiling point of the solvent contained in the curable composition is 135° C. or higher, the intermittent discharge performance of the spray is excellent, and the boiling point is preferably 145° C. or higher and 250° C. or lower, more preferably 150° C. or higher and 200° C. or lower.

[0414] It was found that, when the surface tension of the nonvolatile components other than the solvent at 23°C is defined as γ1 [mN / m] and the surface tension of the solvent at 23°C is defined as γ2 [mN / m], if γ1 is 30 or less, γ2 is 24 or less, and γ1 is greater than γ2, the filling performance is excellent. It was also found that γ1-γ2>0.1 is preferred, and γ1-γ2>1 is more preferred.

[0415] 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.

Claims

1. A curable composition comprising a polymerizable compound (a), a photopolymerization initiator (b) and a solvent (c), wherein: The viscosity of the curable composition at 23° C. and 1 atm is not less than 1.3 mPa·s and not more than 60 mPa·s, The content of the solvent (c) relative to the entire curable composition is not less than 5 volume % and not more than 95 volume %, The boiling point of the solvent (c) at 1 atm is not less than 135°C, and The surface tension of the composition obtained by removing the solvent (c) from the curable composition at 1 atm is defined as γ1 [mN / m], the surface tension of the solvent (c) at 23° C. and 1 atm is defined as γ2 [mN / m], γ1 is not greater than 30, γ2 is not greater than 24, and γ1 is greater than γ2.

2. The curable composition according to claim 1, wherein γ1-γ2>0.1[mN / m].

3. The curable composition according to claim 1, wherein γ1-γ2>1[mN / m].

4. The curable composition according to claim 1, wherein The solvent (c) contains not more than 10 at % of silicon atoms or fluorine atoms.

5. The curable composition according to claim 1, wherein The polymerizable compound (a) includes a compound containing a silicon atom or a fluorine atom.

6. The curable composition according to claim 1, wherein The boiling point of the solvent (c) at 1 atm is not lower than 130°C and lower than 250°C.

7. The curable composition according to claim 1, wherein The solvent (c) includes polyol ethers obtained by etherifying all hydroxyalkyl groups of polyol.

8. The curable composition according to claim 1, wherein The solvent (c) contains one of ethylene glycol di-tert-butyl ether and diethylene glycol methyl tert-butyl ether.

9. A curable composition comprising a polymerizable compound (a), a photopolymerization initiator (b) and a solvent (c), wherein: The viscosity of the curable composition at 23° C. and 1 atm is not less than 1.3 mPa·s and not more than 60 mPa·s, The content of the solvent (c) relative to the entire curable composition is not less than 5 volume % and not more than 95 volume %, and The solvent (c) contains one of ethylene glycol di-tert-butyl ether and diethylene glycol methyl tert-butyl ether.

10. A film forming method for forming a film of a curable composition in a space between a mold and a substrate, the film forming method comprising: an arranging step of discretely arranging a plurality of droplets of the curable composition defined in claim 1 or 9 on one of the substrate and the mold; a waiting step of waiting until each of the plurality of droplets combines with an adjacent droplet to form a liquid film; as well as The contacting step, after waiting, brings the mold and the liquid film into contact with each other.

11. The film forming method according to claim 10, wherein In the waiting step, waiting is performed until the solvent contained in the liquid film evaporates and the content of the solvent does not exceed 10 volume % relative to the entire liquid film.

12. The film forming method according to claim 10, wherein In the waiting step, the substrate is heated under the conditions of not lower than 30° C. and not higher than 200° C. and for not less than 10 seconds and not more than 600 seconds.

13. The film forming method according to claim 10, wherein: In the arranging step, droplets of the curable composition each having a volume of not less than 1.0 pL are arranged at a rate of not less than 130 / mm 2 density arrangement.

14. The film forming method according to claim 10, wherein The average film thickness, which is a value obtained by dividing the volume of the curable composition remaining after the waiting by the area of ​​the film-forming region where the film is formed, is not more than 10 μm.

15. The film forming method according to claim 10, wherein The mold includes a master mold, and The substrate includes a mold base.

16. The film forming method according to claim 15, wherein The master mold includes a pattern, and The film forming method further includes curing the film after bringing the mold and the liquid film into contact with each other to form a cured film having a pattern corresponding to the pattern of the master mold.

17. The film forming method according to claim 10, wherein: In the arranging step, a plurality of liquid droplets are discretely arranged using a jetting method.

18. A manufacturing method, comprising: The replica mold is manufactured by forming a cured film having a pattern corresponding to the master mold pattern on the mold substrate using the film forming method defined in claim 16.

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