JP2013179159A - Curable composition for imprint, patterning method and pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable composition for imprint having high cured film strength, excellent peelability and patternability, few defects, and exhibiting excellent line edge roughness after etching when used for processing a substrate, and to provide a patterning method using the curable composition for imprint, and a pattern obtained by the patterning method.SOLUTION: The curable composition for imprint contains a polymerizable monomer (A), and a photoinitiator (B). The polymerizable monomer (A) contains a first polymerizable monomer (Ax) represented by a compound Ax-5, and a second polymerizable monomer different from the first polymerizable monomer.

Description

  The present invention relates to a curable composition for imprints. More specifically, semiconductor integrated circuits, flat screens, micro electro mechanical systems (MEMS), sensor elements, optical recording media such as high-density memory disks, optical components such as diffraction gratings and relief holograms, nano devices, optical devices, Optical films and polarizing elements for manufacturing flat panel displays, thin film transistors for liquid crystal displays, organic transistors, color filters, overcoat layers, pillar materials, rib materials for liquid crystal alignment, microlens arrays, immunoassay chips, DNA separation chips The present invention relates to a curable composition for imprinting for forming a fine pattern using light irradiation, which is used for producing a microreactor, nanobiodevice, optical waveguide, optical filter, photonic liquid crystal, and the like.

  The nanoimprint method has been developed by developing an embossing technique that is well-known in optical disc production, and mechanically pressing a mold master (generally called a mold, stamper, or template) with a concavo-convex pattern onto a resist. This is a technology that precisely deforms and transfers fine patterns. Once the mold is made, it is economical because nanostructures and other microstructures can be easily and repeatedly molded, and it is economical, and since it is a nano-processing technology with less harmful waste and emissions, it has recently been applied to various fields. Is expected.

  The nanoimprint method includes two methods: a thermal imprint method using a thermoplastic resin as a material to be processed (for example, see Non-Patent Document 1) and an optical imprint method using a curable composition (for example, see Non-Patent Document 2). Street technology has been proposed. In the case of the thermal nanoimprint method, the mold is pressed on a polymer resin heated to a temperature higher than the glass transition temperature, and the mold is released after cooling to transfer the fine structure to the resin on the substrate. Since this method can be applied to various resin materials and glass materials, application to various fields is expected. For example, Patent Documents 1 and 2 disclose a nanoimprint method for forming a nanopattern at low cost using a thermoplastic resin.

  On the other hand, in the optical nanoimprint method in which light is irradiated through a transparent mold or a transparent substrate and the curable composition for optical nanoimprint is photocured, it is not necessary to heat the material transferred when the mold is pressed, and imprinting at room temperature is possible. It becomes possible. Recently, new developments such as a nanocasting method combining the advantages of both and a reversal imprint method for producing a three-dimensional laminated structure have been reported.

In such a nanoimprint method, the following applied technologies have been proposed.
The first technique is a case where a molded shape (pattern) itself has a function and can be applied as various nanotechnology element parts or structural members. Examples include various micro / nano optical elements, high-density recording media, optical films, and structural members in flat panel displays. The second technology is to build a laminated structure by simultaneous molding of microstructure and nanostructure and simple interlayer alignment, and apply this to the production of μ-TAS (Micro-Total Analysis System) and biochips. It is what. The third technique is used for processing a substrate by a method such as etching using the formed pattern as a mask. In this technology, high-precision alignment and high integration enable high-density semiconductor integrated circuit fabrication, liquid crystal display transistor fabrication, and magnetic media for next-generation hard disks called patterned media instead of conventional lithography technology. It can be applied to processing. In recent years, efforts have been made to put the nanoimprint method relating to these applications into practical use.

  As an application example of the nanoimprint method, first, an application example for manufacturing a high-density semiconductor integrated circuit will be described. 2. Description of the Related Art In recent years, semiconductor integrated circuits have been miniaturized and integrated, and photolithography apparatuses have been improved in accuracy as a pattern transfer technique for realizing the fine processing. However, it has become difficult to satisfy three requirements of fine pattern resolution, apparatus cost, and throughput for further miniaturization requirements. On the other hand, nanoimprint lithography (optical nanoimprint method) has been proposed as a technique for performing fine pattern formation at low cost. For example, Patent Documents 1 and 3 listed below disclose nanoimprint technology that uses a silicon wafer as a stamper and forms a fine structure of 25 nm or less by transfer. In this application, a pattern forming property of a level of several tens of nanometers and a high etching resistance for functioning as a mask during substrate processing are required.

An application example of the nanoimprint method to the production of the next generation hard disk drive (HDD) will be described.
HDDs have increased in capacity by increasing the surface recording density. However, when the recording density is increased, so-called magnetic field spreading from the side surface of the magnetic head becomes a problem. Since the magnetic field spread does not become smaller than a certain value even if the head is made smaller, a phenomenon called sidelight occurs as a result. When side writing occurs, writing to an adjacent track occurs during recording, and already recorded data is erased. Further, due to the magnetic field spread, a phenomenon such as reading an excessive signal from an adjacent track occurs during reproduction. In order to solve such a problem, technologies such as discrete track media and bit patterned media have been proposed which are solved by filling the spaces between tracks with a nonmagnetic material and physically and magnetically separating the tracks. The application of nanoimprinting has been proposed as a method for forming a magnetic or nonmagnetic pattern in the production of these media. Also in this application, a pattern forming property of several tens of nm level and high etching resistance for functioning as a mask during substrate processing are required.

Next, an application example of the nanoimprint method to a flat display such as a liquid crystal display (LCD) or a plasma display (PDP) will be described.
With the trend toward larger and higher definition LCD substrates and PDP substrates, the optical nanoimprint method has recently attracted attention as an inexpensive lithography that replaces the conventional photolithography method used in the manufacture of thin film transistors (TFTs) and electrode plates. Yes. Therefore, it has become necessary to develop a photo-curable resist that replaces the etching photoresist used in the conventional photolithography method.
Further, as a structural member such as an LCD, application of the optical nanoimprint method to the transparent protective film material described in Patent Document 4 and Patent Document 5, the spacer described in Patent Document 5, and the like has begun to be studied. Unlike the etching resist, such a resist for a structural member is finally left in the display, and is sometimes referred to as “permanent resist” or “permanent film”.
In addition, a spacer that defines a cell gap in a liquid crystal display is also a kind of permanent film. In conventional photolithography, a photocurable composition comprising a resin, a photopolymerizable monomer, and an initiator has been widely used. (For example, see Patent Document 6). The spacer is generally a pattern having a size of about 10 μm to 20 μm by photolithography after applying the photocurable composition after forming the color filter on the color filter substrate or after forming the protective film for the color filter. And is further heated and cured by post-baking.
The nanoimprint method can also be used to create an antireflection structure generally called moth eye. By forming innumerable fine irregularities made of a transparent material on the surface of the transparent molded article at a pitch equal to or less than the wavelength of light, an antireflection structure in which the refractive index of light changes in the thickness direction can be formed. Since the refractive index of such an antireflection structure continuously changes in the thickness direction, there is no refractive index interface, and theoretically it can be made non-reflective. Further, since the wavelength dependency is small and the antireflection performance against oblique light is high, the antireflection performance superior to that of the multilayer antireflection film is provided.

Furthermore, microelectromechanical systems (MEMS), sensor elements, optical components such as diffraction gratings and relief holograms, nanodevices, optical devices, optical films and polarizing elements for the production of flat panel displays, thin film transistors for liquid crystal displays, organic transistors , Color filter, overcoat layer, pillar material, rib material for liquid crystal alignment, microlens array, immunoassay chip, DNA separation chip, microreactor, nanobiodevice, optical waveguide, optical filter, photonic liquid crystal, etc. Nanoimprint lithography is also useful in applications.
In these permanent film applications, the formed pattern will eventually remain in the product, so the durability of the film, mainly heat resistance, light resistance, solvent resistance, scratch resistance, high mechanical properties against external pressure, hardness, etc. And strength-related performance is required.
As described above, most of the patterns conventionally formed by the photolithography method can be formed by nanoimprinting, and attention has been paid as a technique capable of forming a fine pattern at low cost.

In order to use nanoimprint in the industry, in addition to good pattern formability, characteristics according to the application as described above, and also high productivity are required. To achieve high productivity, high-speed patterning is required. Also in the transfer, performances such as good pattern formability and few defects, and excellent mold releasability even when a repetitive mold is used are required.
Patent Documents 7 to 9 disclose that when a photocurable composition containing a fluorine-containing monomer is used for nanoimprinting, good pattern forming properties are exhibited. However, even if these compositions are used, pattern formation and defect performance deteriorate when pattern transfer is performed at high speed, and so-called line edge roughness that causes irregularities on the pattern side wall after etching deteriorates when used for substrate processing. There was a problem.
Moreover, although the thing of patent document 10 is known as a curable composition for imprints containing a fluorine-containing polymerizable monomer, there is neither description nor suggestion about performing pattern transfer at high speed. Moreover, there was no description regarding the durability and strength of the cured film, and there was room for study.
Although the thing of patent document 11 is also known from a viewpoint of a polymerizable fluorine-containing monomer, there is no description or suggestion about the use as a curable composition for imprints.

US Pat. No. 5,772,905 US Pat. No. 5,956,216 US Pat. No. 5,259,926 JP 2005-197699 A Japanese Patent Laying-Open No. 2005-301289 Japanese Patent Laid-Open No. 2004-240241 JP 2006-310565 A JP 2008-95037 A JP 2006-137021 A JP 2010-239121 A JP 2006-028280 A

S. Chou et al. : Appl. Phys. Lett. Vol. 67, 3114 (1995) M.M. Colbun et al ,: Proc. SPIE, Vol. 3676, 379 (1999)

  The object of the present invention is to solve the above-mentioned problems, and has a high cured film strength, excellent releasability, good pattern forming properties even when pattern transfer is performed at high speed, and defects. It aims at providing the curable composition for imprints with few. Furthermore, an object of the present invention is to provide a curable composition for imprints having good line edge roughness after etching when used for substrate processing. Moreover, it is providing the pattern obtained by the pattern formation method using this curable composition for imprints, and this pattern formation method.

  As a result of intensive studies by the inventors of the present invention based on the above problems, the cured film strength can be increased by using a fluorine-containing compound having three or more specific polymerizable groups in combination with another polymerizable monomer. Providing a curable composition for imprints that has a high level, excellent releasability, good pattern formation, few defects, and good line edge roughness after etching when used in substrate processing applications We have found that this is possible and have completed the invention. Specifically, the above problems have been achieved by the following means.

[1]
A curable composition for imprints containing a polymerizable monomer (A) and a photopolymerization initiator (B), wherein at least one of the following general formulas (A) Curability for imprints containing the first polymerizable monomer (Ax) represented by 1) and a second polymerizable monomer different from the first polymerizable monomer (Ax) Composition.
Formula (1): Rf {-(L) m-Y} n
(In the formula, Rf represents an n-valent group selected from the following f-1 to f-10, n represents an integer of 3 to 6, and L represents an alkylene group having 1 to 10 carbon atoms and 6 to 6 carbon atoms. It is obtained by combining 10 arylene groups, -O-, -S-, -N (R)-, an alkylene group having 1 to 10 carbon atoms and -O-, -S-, or -N (R)-. Or a group obtained by combining an arylene group having 6 to 10 carbon atoms and —O—, —S—, or —N (R) —, wherein R represents a hydrogen atom or an alkyl having 1 to 5 carbon atoms; M represents 0 or 1. Y represents a polymerizable group selected from a (meth) acryloyl group, an allyl group, an α-fluoroacryloyl group, an epoxy group, and —C (O) OCH═CH _2. .)

[2]
The curable composition for imprints according to the above [1], wherein the first polymerizable monomer (Ax) is any one of the following Ax-1 to Ax-13.

[3]
The curable composition for imprints according to the above [1] or [2], wherein the viscosity of the mixed liquid of all components excluding the solvent is 100 mPa · s or less.
[4]
The other polymerizable monomer different from the first polymerizable monomer (Ax) is a (meth) acrylate having an aromatic group, an alicyclic hydrocarbon group, or a Si atom, [1] to [1] [3] The curable composition for imprints according to any one of [3].
[5]
The curable composition for imprints according to any one of [1] to [4], wherein the first polymerizable monomer (Ax) is contained in an amount of 0.1 to 5% by mass of the total polymerizable monomer component. Composition.
[6]
Furthermore, the curable composition for imprints according to any one of the above [1] to [5], further comprising a polymerization inhibitor.
[7]
Applying the curable composition for imprints according to any one of [1] to [6] above onto a substrate to form a pattern forming layer, and pressing the mold against the surface of the pattern forming layer A pattern forming method comprising: a step; and a step of irradiating the pattern forming layer with light.
[8]
The pattern forming method according to [7], wherein the method for applying the curable composition for imprints onto a substrate is an inkjet method.
[9]
The pattern obtained by the pattern formation method as described in said [7] or [8].

  When the composition of the present invention is used as a curable composition for imprints, it has high cured film strength, excellent releasability, good pattern formability, few defects, and etching when used for substrate processing applications. It is possible to provide a curable composition for imprints having good later line edge roughness.

  Hereinafter, the contents of the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

In the present specification, “(meth) acrylate” represents acrylate and methacrylate, “(meth) acryl” represents acryl and methacryl, and “(meth) acryloyl” represents acryloyl and methacryloyl. In the present specification, “monomer” and “monomer” are synonymous. The monomer in the present invention is distinguished from oligomers and polymers, and refers to a compound having a weight average molecular weight of 2,000 or less.
The “imprint” referred to in the present invention preferably refers to pattern transfer having a size of 1 nm to 10 mm, and more preferably refers to pattern transfer having a size (nanoimprint) of approximately 10 nm to 100 μm.
Furthermore, in the description of the group (atomic group) in this specification, the description which does not describe substitution and unsubstituted includes the thing which has a substituent with the thing which does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

[Curable composition for imprints of the present invention]
The curable composition for imprints of the present invention (hereinafter sometimes simply referred to as “the curable composition of the present invention” or “the composition of the present invention”) is composed of a polymerizable monomer (A) and a photopolymerization. A curable composition for imprints containing an initiator (B), wherein the polymerizable monomer (A) is at least one first polymerizable monomer represented by the following general formula (1). It contains a monomer (Ax) and a second polymerizable monomer different from the polymerizable monomer (Ax).

(Polymerizable monomer (A))
-First polymerizable monomer (Ax)-
The first polymerizable monomer (Ax) of the present invention mainly comprises a plurality of fluorine atoms and carbon atoms (however, it may partially contain oxygen atoms and / or hydrogen atoms) and is substantially polymerized. 3 to 6 having radical polymerizability or cationic polymerizability via an atomic group that does not participate in (hereinafter also referred to as “fluorinated core portion”) and a linking group such as an ester bond or an ether bond. It is a fluorine-containing compound having one polymerizable group, and preferably has 4 to 6 and most preferably 4 polymerizable groups. By having three or more polymerizable groups, the crosslink density of the polymer is increased, and the strength of the cured film obtained is improved.
Further, the first polymerizable monomer (Ax) of the present invention preferably has a fluorine content of 35 to 60% by mass of the fluorine-containing compound, more preferably 40 to 55% by mass, and still more preferably. It is 40-50 mass%. By setting the fluorine content in the above range, mold contamination can be reduced and the line edge roughness after dry etching is improved.
The first polymerizable monomer (Ax) of the present invention may be a crosslinking agent having a polymerizable group as a crosslinkable group.

The first polymerizable monomer (Ax) of the present invention is represented by the following general formula (1).
General formula (1): Rf {-(L) m-Y} n

(In the formula, Rf represents an n-valent group selected from the following f-1 to f-10, n represents an integer of 3 to 6, and L represents an alkylene group having 1 to 10 carbon atoms and 6 to 6 carbon atoms. It is obtained by combining 10 arylene groups, -O-, -S-, -N (R)-, an alkylene group having 1 to 10 carbon atoms and -O-, -S-, or -N (R)-. Or a group obtained by combining an arylene group having 6 to 10 carbon atoms and —O—, —S—, or —N (R) —, wherein R represents a hydrogen atom or an alkyl having 1 to 5 carbon atoms; M represents 0 or 1. Y represents a polymerizable group selected from a (meth) acryloyl group, an allyl group, an α-fluoroacryloyl group, an epoxy group, and —C (O) OCH═CH _2. .)

In general formula (1), Rf represents a "fluorine-containing core part", represents an n-valent group selected from the above f-1 to f-10, and n represents an integer of 3 or more.
1/4 or less is preferable and the number of hydrogen atoms / fluorine atoms in Rf is more preferably 1/9 or less. n represents an integer of 3 or more and 6 or less, and n is preferably 4 or more and 6 or less, and most preferably 4.
Rf is preferably a group having a molecular weight between crosslinks of 300 or less when all polymerizable groups are polymerized. The molecular weight between crosslinks will be described later.
Rf is preferably f-1, f-6, or f-7, more preferably f-1 or f-6, and f-6 from the viewpoints of compound viscosity and crosslinking reactivity. Most preferred.

L is an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, -O-, -S-, -N (R)-, an alkylene group having 1 to 10 carbon atoms and -O-, -S. A group obtained by combining-or -N (R)-, or a group obtained by combining an arylene group having 6 to 10 carbon atoms with -O-, -S-, or -N (R)- Represents.
Examples of the alkylene group having 1 to 10 carbon atoms include a methylene group, an ethylene group, and a propylene group, and a methylene group is preferable.
Examples of the arylene group having 6 to 10 carbon atoms include a phenylene group and a naphthylene group.
When L represents an alkylene group or an arylene group, the alkylene group and the arylene group represented by L may be substituted with a halogen atom, and when substituted with a halogen atom, it is preferably substituted with a fluorine atom. .
L is a group obtained by combining a single bond (that is, m = 0), —O—, or an alkylene group having 1 to 10 carbon atoms and —O— from the viewpoint of compound viscosity and compound synthesis. A group obtained by combining —O— or an alkylene group having 1 to 10 carbon atoms and —O— is more preferable. The group obtained by combining the alkylene group having 1 to 10 carbon atoms and —O— may be substituted with a halogen atom, but is preferably not substituted with a halogen atom.

Y represents a polymerizable group selected from a (meth) acryloyl group, an allyl group, an α-fluoroacryloyl group, an epoxy group, and —C (O) OCH═CH ₂ .
Among these, Y is preferably a (meth) acryloyl group or —C (O) OCH═CH ₂ from the viewpoint of polymerizability.

  R represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R is preferably a hydrogen atom or a methyl group, more preferably a hydrogen atom.

  m represents 0 or 1;

  More preferred as the fluorine-containing polyfunctional monomer of the present invention is one represented by the formula (2) or (3).

Equation (2) Rf- {OC (O ) CH = CH 2} n
Equation (3) Rf- {C (O ) OCH = CH 2} n
In the above formula, Rf and n have the same meaning as in formula (1), and the preferred range is also the same.

  Although the preferable specific example of the 1st polymerizable monomer (Ax) of this invention is given to the following, this invention is not limited by these.

The fluorine contents of Ax-1 to Ax-13 are 37.5, 46.2, 48.6, 49.8, 36.6, 39.8, 47.0, 35.1, 44.9, respectively. 42.5, 36.2, 36.7, 45.8 mass%.
Of Ax-1 to Ax-13, Ax-2 to Ax-5 or Ax-9 to Ax-11 are preferable from the viewpoint of compound viscosity and crosslinking reactivity, and Ax-5 or Ax-9 to Ax. It is more preferably −11, and most preferably Ax-9 or Ax-10.

  The first polymerizable monomer (Ax) of the present invention is a calculated value of the molecular weight between crosslinks when all the polymerizable groups of the first polymerizable monomer (Ax) are polymerized from the viewpoint of crosslink density. It is preferable to have a fluorine-containing core portion Rf in which all are 300 or less. The calculated value of the molecular weight between crosslinks is a polymer in which all the polymerizable groups of the first polymerizable monomer (Ax) are polymerized, and a total of three or more carbon atoms or silicon atoms substituted by silicon atoms (a ), (A) and (a), (b) and (b), or (a) and (b), when a silicon atom substituted with 3 or more carbon atoms or oxygen atoms is defined as (b) It refers to the molecular weight of an atomic group sandwiched between. For example, Ax-2 will be described as an example of the first polymerizable monomer (Ax). Assuming that all the polymerizable groups of Ax-2 are polymerized, it is expressed as shown in Formula (4).

Formula (4)

In this case, the partial structure which is the target of calculation of the molecular weight between crosslinks defined above is a portion surrounded by a broken line in the formula (4), and the calculated value of the molecular weight between crosslinks is C ₂ F ₄ O = 116, respectively. 0.0 and C ₅ H ₂ F ₆ O ₃ = 224.1, both of which are 300 or less.

  The calculated value of the molecular weight between crosslinks is more preferably 250 or less, and still more preferably 200 or less.

  As a method for producing these fluorine-containing polyfunctional monomers, a compound having an ester bond, a dialkoxy group, and / or a halogen atom is subjected to liquid phase fluorination, whereby 80 mol% or more, preferably 90 mol% or more of hydrogen. A method of introducing 3 to 6 polymerizable groups, preferably 4 to 6 polymerizable groups, after substituting atoms with fluorine atoms is suitable. Most preferably, four polymerizable groups are introduced. Liquid phase fluorination is described, for example, in US Pat. No. 5,093,432.

The compound to be subjected to liquid phase fluorination is required to be dissolved in a fluorine-based solvent used for liquid phase fluorination or to be liquid, but there is no particular limitation other than that. From the viewpoint of such solubility and reactivity, a compound containing fluorine in advance may be used. In addition, a compound having an ester bond, a dialkoxy group, and / or a halogen atom is preferable because it can serve as a reaction point when a polymerizable group is introduced after liquid phase fluorination.
By introducing fluorine atoms by liquid phase fluorination, it is possible to extremely increase the fluorine content of the portion other than the polymerizable group to be introduced later, and give a resin with extremely high water and ink repellency. A first polymerizable monomer (Ax) can be obtained.

  The content of (Ax) in the curable composition of the present invention is not particularly limited, but is preferably 0.01 to 50% by mass in the total polymerizable monomer from the viewpoint of curability and composition viscosity. 0.02 to 25% by mass is more preferable, 0.05 to 10% by mass is further preferable, and 0.1 to 5% by mass is particularly preferable.

-Second polymerizable monomer-
In the curable composition of the present invention, the second polymerizable property different from the first polymerizable monomer (Ax) from the viewpoint of improving the composition viscosity, dry etching resistance, imprint suitability, curability and the like. Contains monomer.
Examples of the second polymerizable monomer include a polymerizable unsaturated monomer having 1 to 6 ethylenically unsaturated bond-containing groups; a compound having an oxirane ring (epoxy compound); a vinyl ether compound; a styrene derivative. A compound having a fluorine atom; a propenyl ether or a butenyl ether, and the like. From the viewpoint of curability, a polymerizable unsaturated monomer having 1 to 6 ethylenically unsaturated bond-containing groups is preferable.

The polymerizable unsaturated monomer having 1 to 6 ethylenically unsaturated bond-containing groups (1 to 6 functional polymerizable unsaturated monomer) will be described.
First, specific examples of the polymerizable unsaturated monomer having one ethylenically unsaturated bond-containing group (monofunctional polymerizable unsaturated monomer) include 2-acryloyloxyethyl phthalate, 2-acryloyloxy 2 -Hydroxyethyl phthalate, 2-acryloyloxyethyl hexahydrophthalate, 2-acryloyloxypropyl phthalate, 2-ethyl-2-butylpropanediol acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylhexyl carbitol (meth) Acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 4-hydroxy Butyl (medium ) Acrylate, acrylic acid dimer, benzyl (meth) acrylate, 1- or 2-naphthyl (meth) acrylate, butanediol mono (meth) acrylate, butoxyethyl (meth) acrylate, butyl (meth) acrylate, cetyl (meth) acrylate , Ethylene oxide modified (hereinafter referred to as “EO”) cresol (meth) acrylate, dipropylene glycol (meth) acrylate, ethoxylated phenyl (meth) acrylate, ethyl (meth) acrylate, isoamyl (meth) acrylate, isobutyl (meth) acrylate , Isooctyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclohentanyl (meth) acrylate, dicyclopentanyloxyethyl (Meth) acrylate, isomyristyl (meth) acrylate, lauryl (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxytriethylene glycol (meta ) Acrylate, methyl (meth) acrylate, neopentyl glycol benzoate (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolypropylene glycol (meth) acrylate, octyl (meth) acrylate, paracumylphenoxyethylene glycol (meth) Acrylate, epichlorohydrin (hereinafter referred to as “ECH”) modified phenoxy acrylate, phenoxyethyl ( Acrylate), phenoxydiethylene glycol (meth) acrylate, phenoxyhexaethylene glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate, polyethylene glycol-polypropylene glycol (meth) acrylate, polypropylene glycol (meth) ) Acrylate, stearyl (meth) acrylate, EO-modified succinic acid (meth) acrylate, tert-butyl (meth) acrylate, tribromophenyl (meth) acrylate, EO-modified tribromophenyl (meth) acrylate, tridodecyl (meth) acrylate, Examples are p-isopropenylphenol, styrene, α-methylstyrene, and acrylonitrile.

  Among these, a monofunctional (meth) acrylate having an aromatic structure and / or an alicyclic hydrocarbon structure is preferable from the viewpoint of improving dry etching resistance, and a monofunctional (meth) acrylate having an aromatic structure is more preferable. . Specific examples include benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, 1- or 2-naphthyl (meth) acrylate, 1- or 2-naphthylmethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, Dicyclopentanyloxyethyl (meth) acrylate, isobornyl (meth) acrylate, and adamantyl (meth) acrylate are preferred, and benzyl (meth) acrylate, 1- or 2-naphthyl (meth) acrylate, 1- or 2-naphthylmethyl ( Particularly preferred is (meth) acrylate.

It is also preferable to use a polyfunctional polymerizable unsaturated monomer having two ethylenically unsaturated bond-containing groups as the second polymerizable monomer.
Examples of the bifunctional polymerizable unsaturated monomer having two ethylenically unsaturated bond-containing groups that can be preferably used in the present invention include diethylene glycol monoethyl ether (meth) acrylate, dimethylol dicyclopentane di (meta ) Acrylate, di (meth) acrylated isocyanurate, 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, EO-modified 1,6-hexanediol di (meth) acrylate, ECH modified 1,6-hexanediol di (meth) acrylate, allyloxy polyethylene glycol acrylate, 1,9-nonanediol di (meth) acrylate, EO modified bisphenol A di (meth) acrylate, PO modified bisphenol A di (meth) Acrylate, modified screw Enol A di (meth) acrylate, EO modified bisphenol F di (meth) acrylate, ECH modified hexahydrophthalic acid diacrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, EO modified Neopentyl glycol diacrylate, propylene oxide (hereinafter referred to as “PO”) modified neopentyl glycol diacrylate, caprolactone modified hydroxypivalate ester neopentyl glycol, stearic acid modified pentaerythritol di (meth) acrylate, ECH modified phthalic acid di ( (Meth) acrylate, poly (ethylene glycol-tetramethylene glycol) di (meth) acrylate, poly (propylene glycol-tetramethylene glycol) ) Di (meth) acrylate, polyester (di) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, ECH-modified propylene glycol di (meth) acrylate, silicone di (meth) acrylate, ethylene glycol Di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, neopentyl glycol modified trimethylolpropane di (meth) acrylate, tripropylene Glycol di (meth) acrylate, EO-modified tripropylene glycol di (meth) acrylate, triglycerol di (meth) acrylate, dipropylene glycol Examples thereof include di (meth) acrylate, divinylethyleneurea and divinylpropyleneurea.

  Among these, neopentyl glycol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, neopentyl hydroxypivalate Glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, dicyclopentane dimethanol di (meth) acrylate, p- or m-xylylene di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, etc. It is suitably used in the present invention. Among these, (meth) acrylates having an aromatic structure and / or an alicyclic hydrocarbon structure are preferable from the viewpoint of improving dry etching resistance.

  Examples of the polyfunctional polymerizable unsaturated monomer having 3 or more ethylenically unsaturated bond-containing groups include ECH-modified glycerol tri (meth) acrylate, EO-modified glycerol tri (meth) acrylate, PO-modified glycerol tri (meta) ) Acrylate, pentaerythritol triacrylate, EO modified phosphoric acid triacrylate, trimethylolpropane tri (meth) acrylate, caprolactone modified trimethylolpropane tri (meth) acrylate, EO modified trimethylolpropane tri (meth) acrylate, PO modified trimethylol Propane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) Acrylate, dipentaerythritol hydroxypenta (meth) acrylate, alkyl-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol poly (meth) acrylate, alkyl-modified dipentaerythritol tri (meth) acrylate, ditrimethylolpropane tetra (meth) Examples include acrylate, pentaerythritol ethoxytetra (meth) acrylate, and pentaerythritol tetra (meth) acrylate.

  Among these, EO-modified glycerol tri (meth) acrylate, PO-modified glycerol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, PO-modified trimethylolpropane tri (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol ethoxytetra (meth) acrylate, pentaerythritol tetra (meth) acrylate and the like are preferably used in the present invention.

  Among the (meth) acrylate compounds, acrylate compounds are preferred from the viewpoint of curability.

  Examples of the compound having an oxirane ring (epoxy compound) include polyglycidyl esters of polybasic acids, polyglycidyl ethers of polyhydric alcohols, polyglycidyl ethers of polyoxyalkylene glycol, and polyglycidyl ethers of aromatic polyols. Examples include teters, hydrogenated compounds of polyglycidyl ethers of aromatic polyols, urethane polyepoxy compounds, and epoxidized polybutadienes. These compounds can be used alone or in combination of two or more thereof.

  Examples of the compound having an oxirane ring (epoxy compound) that can be preferably used in the present invention include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, brominated bisphenol A diglycidyl ether, bromine Bisphenol F diglycidyl ether, brominated bisphenol S diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hydrogenated bisphenol S diglycidyl ether, 1,4-butanediol diglycidyl ether, 1 , 6-hexanediol diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyethylene glycol di Glycidyl ethers, polypropylene glycol diglycidyl ethers; polyglycidyl ethers of polyether polyols obtained by adding one or more alkylene oxides to aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin; Diglycidyl esters of aliphatic long-chain dibasic acids; monoglycidyl ethers of higher aliphatic alcohols; monoglycidyl ethers of polyether alcohols obtained by adding phenol, cresol, butylphenol or alkylene oxide to these; higher fatty acid Examples thereof include glycidyl esters.

  Among these, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol Diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, neopentyl glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether are preferred.

  Commercially available products that can be suitably used as the glycidyl group-containing compound include UVR-6216 (manufactured by Union Carbide), glycidol, AOEX24, cyclomer A200, (manufactured by Daicel Chemical Industries, Ltd.), Epicoat 828, Epicoat 812, Epicoat 1031, Epicoat 872, Epicoat CT508 (above, manufactured by Yuka Shell Co., Ltd.), KRM-2400, KRM-2410, KRM-2408, KRM-2490, KRM-2720, KRM-2750 (above, Asahi Denka Kogyo ( Product)). These can be used individually by 1 type or in combination of 2 or more types.

  The compound having these oxirane rings may be produced by any method, for example, see Maruzen KK Publishing, 4th Edition Experimental Chemistry Course 20 Organic Synthesis II, 213, 1992, Ed. By Alfred Hasfner, The Chemistry of Heterocyclic compounds, Vol. 30, Advertisement, Small Ring Heterocycle part3 Oxilanes, John & Wiley and Sons, An Inc. No. 5, 42, 1986, Yoshimura, Adhesion, Vol. 30, No. 7, 42, 1986, Japanese Patent Application Laid-Open No. 11-1000037, Japanese Patent No. 2906245, Japanese Patent No. 2926262, and the like.

  A vinyl ether compound may be used in combination as the second polymerizable monomer used in the present invention. As the vinyl ether compound, known compounds can be appropriately selected. For example, 2-ethylhexyl vinyl ether, butanediol-1,4-divinyl ether, diethylene glycol monovinyl ether, diethylene glycol monovinyl ether, ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,2-propanediol divinyl ether, 1,3-propanediol divinyl ether, 1,3-butanediol divinyl ether, 1,4-butanediol divinyl ether, tetramethylene glycol divinyl ether, neopentyl glycol divinyl ether, trimethylol Propane trivinyl ether, trimethylol ethane trivinyl ether, hexanediol divinyl ether, tetra Tylene glycol divinyl ether, pentaerythritol divinyl ether, pentaerythritol trivinyl ether, pentaerythritol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, ethylene glycol diethylene vinyl ether, triethylene glycol diethylene vinyl ether, ethylene glycol dipropylene vinyl ether, triethylene glycol diethylene vinyl ether , Trimethylolpropane triethylene vinyl ether, trimethylolpropane diethylene vinyl ether, pentaerythritol diethylene vinyl ether, pentaerythritol triethylene vinyl ether, pentaerythritol tetraethylene vinyl ether, 1,1,1-to Scan [4- (2-vinyloxy ethoxy) phenyl] ethane, bisphenol A divinyloxyethyl carboxyethyl ether.

  These vinyl ether compounds are described in, for example, Stephen. C. Lapin, Polymers Paint Color Journal. 179 (4237), 321 (1988), that is, synthesis by reaction of polyhydric alcohol or polyhydric phenol and acetylene, or reaction of polyhydric alcohol or polyhydric phenol and halogenated alkyl vinyl ether. These can be used singly or in combination of two or more.

  Moreover, a styrene derivative can also be employ | adopted as a 2nd polymerizable monomer used by this invention. Examples of styrene derivatives include styrene, p-methylstyrene, p-methoxystyrene, β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene, p-methoxy-β-methylstyrene, p-hydroxy. Examples include styrene.

  In addition, trifluoroethyl (meth) acrylate, pentafluoroethyl (meth) acrylate, (perfluorobutyl) ethyl (meth) acrylate, (perfluorohexyl) ethyl (meth) acrylate, octafluoropentyl (meth) acrylate, perfluoroalkyl First polymerizable monomers such as tilethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, 2,2,3,3,4,4,5,5 octafluorohexanediol di (meth) acrylate ( A compound having a fluorine atom other than Ax) can also be used in combination.

Propenyl ether and butenyl ether can also be used as the second polymerizable monomer used in the present invention. Examples of the propenyl ether or butenyl ether include 1-dodecyl-1-propenyl ether, 1-dodecyl-1-butenyl ether, 1-butenoxymethyl-2-norbornene, 1,4-di (1-butenoxy) butane, 1,10-di (1-butenoxy) decane, 1,4-di (1-butenoxymethyl) cyclohexane, diethylene glycol di (1-butenyl) ether, 1,2,3-tri (1-butenoxy) propane, propenyl ether propylene Carbonate or the like can be suitably applied.
Si atom-containing (meth) acrylate compounds are also preferred as the second polymerizable monomer. Preferred silicon-containing (meth) acrylate compounds include 3- (meth) acryloxypropyltris (trimethylsiloxy) silane, (meth) acryloxymethylbis (trimethylsiloxy) methylsilane, (meth) acryloxymethyltris (trimethylsiloxy) Examples include silane, 3-acryloxypropylbis (trimethylsiloxy) methylsilane, 1,3-bis (3- (meth) acryloxypropyl) tetramethyldisiloxane.
As a 2nd polymerizable monomer, 30-100 mass% of (meth) acrylates containing at least 1 sort (s) of an aromatic group, an alicyclic hydrocarbon group, and Si atom are contained in a 2nd polymerizable monomer. It is preferable to contain, More preferably, it is 70-100 mass%, More preferably, it contains 90-100 mass%.
In a more preferred embodiment, a (meth) acrylate polymerizable monomer containing an aromatic group (preferably a phenyl group, a naphthyl group, and more preferably a naphthyl group) is used as the second polymerizable monomer. It is preferable to contain 50-100 mass% in a weight body, More preferably, it is 70-100 mass%, More preferably, it contains 90-100 mass%.

  As the polymerizable monomer having an aromatic group used in the present invention, a monofunctional (meth) acrylate compound represented by the following general formula (I) or a polyfunctional (meta) represented by the following general formula (II): ) Acrylate compounds are preferred.

(In the general formula, Z represents a group containing an aromatic group, and R ¹ represents a hydrogen atom, an alkyl group or a halogen atom, provided that the first polymerizable monomer (Ax) is liquid at 25 ° C. In some cases, the viscosity at 25 ° C. is 500 mPa · s or less.)
R ¹ is preferably a hydrogen atom or an alkyl group, preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom from the viewpoint of curability. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Z is preferably an aralkyl group which may have a substituent, an aryl group which may have a substituent, or a group in which these groups are bonded via a linking group. The linking group herein may include a linking group containing a hetero atom, and preferably a group consisting of —CH ₂ —, —O—, —C (═O) —, —S—, and combinations thereof. It is. The aromatic group contained in Z is preferably a phenyl group or a naphthyl group. The molecular weight of Z is preferably 90 to 300, more preferably 120 to 250.

When the polymerizable monomer represented by formula (I) is a liquid at 25 ° C., the viscosity at 25 ° C. is preferably 2 to 500 mPa · s, more preferably 3 to 200 mPa · s, and more preferably 3 to 100 mPa · s. s is most preferred. The polymerizable monomer is liquid at 25 ° C, or even if it is solid, the melting point is preferably 60 ° C or lower, more preferably the melting point is 40 ° C or lower, and it is liquid at 25 ° C. Further preferred.
Z is preferably a group represented by -Z ¹ -Z ² . Here, Z ¹ is a single bond or a hydrocarbon group, and the hydrocarbon group may include a linking group containing a hetero atom in the chain. Z ² is an aromatic group which may have a substituent, and has a molecular weight of 90 or more.
Z ¹ is preferably a single bond or an alkylene group, and the alkylene group may contain a linking group containing a hetero atom in the chain. Z ¹ is more preferably an alkylene group that does not contain a linking group containing a hetero atom in the chain, and more preferably a methylene group or an ethylene group. Examples of the linking group containing a hetero atom include —O—, —C (═O) —, —S—, and a group composed of a combination of these and an alkylene group. Moreover, it is preferable that carbon number of a hydrocarbon group is 1-3.

Z ² is also preferably a group in which two or more aromatic groups are linked directly or via a linking group. The linking group in this case is also preferably a group consisting of —CH ₂ —, —O—, —C (═O) —, —S—, and combinations thereof.

  Examples of the substituent that the aromatic group of the polymerizable monomer represented by the general formula (I) may have include, for example, a halogen atom (fluorine atom, chloro atom, bromine atom, iodine). Atom), linear, branched or cyclic alkyl group, alkenyl group, alkynyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, cyano group, carboxyl group, hydroxyl group, alkoxy group, aryloxy Group, alkylthio group, arylthio group, heterocyclic oxy group, acyloxy group, amino group, nitro group, hydrazino group, heterocyclic group and the like. A group further substituted with these groups is also preferred.

The addition amount of the polymerizable monomer represented by the general formula (I) in the photocurable composition is preferably 10 to 100% by mass, more preferably 20 to 100% by mass, 30 It is especially preferable that it is -80 mass%.
Specific examples of the compound represented by the general formula (I) having no substituent on the aromatic ring include benzyl (meth) acrylate, phenethyl (meth) acrylate, phenoxyethyl (meth) acrylate, 1- Or 2-naphthyl (meth) acrylate, 1- or 2-naphthylmethyl (meth) acrylate, 1- or 2-naphthylethyl (meth) acrylate, 1- or 2-naphthoxyethyl (meth) acrylate is preferable.

  As the compound represented by the general formula (I), a compound having a substituent on the aromatic ring represented by the following general formula (III) is also preferable.

(In the general formula (III), R ¹ represents a hydrogen atom, an alkyl group or a halogen atom, X ₁ is a single bond or a hydrocarbon group, and the hydrocarbon group is a linking group containing a hetero atom in the chain. Y ₁ represents a substituent having a molecular weight of 15 or more, n ₁ represents an integer of 1 to 3. Ar represents an aromatic linking group, and is preferably a phenylene group or a naphthylene group.

R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
X ₁ has the same meaning as Z ¹ described above, and the preferred range is also the same.
Y ₁ is a substituent having a molecular weight of 15 or more, and examples thereof include an alkyl group, an alkoxy group, an aryloxy group, an aralkyl group, an acyl group, an alkoxycarbonyl group, an alkylthio group, an arylthio group, a halogen atom, and a cyano group. These substituents may have further substituents.
When n ₁ is 2, X ₁ is preferably a single bond or a hydrocarbon group having 1 carbon atom.
In a particularly preferred embodiment, n ₁ is 1 and X ₁ is an alkylene group having 1 to 3 carbon atoms.

  The compound represented by the general formula (III) is more preferably a compound represented by (IV) or (V).

  Compound represented by general formula (IV):

In general formula (IV), R ¹ represents a hydrogen atom, an alkyl group, or a halogen atom. X ² is a single bond or a hydrocarbon group, and the hydrocarbon group may contain a linking group containing a hetero atom in the chain. Y ² represents a substituent having no aromatic group having a molecular weight of 15 or more, and n ₂ represents an integer of 1 to 3. Ar ₁ represents an aromatic linking group, and is preferably a phenylene group or a naphthylene group.
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
When X ² is a hydrocarbon group, it is preferably a hydrocarbon group having 1 to 3 carbon atoms, preferably a substituted or unsubstituted alkylene group having 1 to 3 carbon atoms, and an unsubstituted carbon number. It is more preferably an alkylene group of 1 to 3, more preferably a methylene group or an ethylene group. By employing such a hydrocarbon group, a photocurable composition having a lower viscosity and lower volatility can be obtained.
Y ² represents a substituent having no aromatic group having a molecular weight of 15 or more, and the upper limit of the molecular weight of Y ² is preferably 150 or less. Y ² is an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group or a cyclohexyl group, a halogen atom such as a fluoro group, a chloro group or a bromo group, a methoxy group or an ethoxy group. Preferred examples include C1-C6 alkoxy groups such as cyclohexyloxy group, and cyano groups.
n ₂ is preferably an integer of 1 to 2. When n ₂ is 1, the substituent Y is preferably in the para position. From the viewpoint of viscosity, when n ₂ is 2, X ² is preferably a single bond or a hydrocarbon group having 1 carbon atom.

From the viewpoint of achieving both low viscosity and low volatility, the molecular weight of the (meth) acrylate compound represented by the general formula (IV) is preferably 175 to 250, and more preferably 185 to 245.
Moreover, it is preferable that the viscosity in 25 degreeC of the (meth) acrylate compound represented by general formula (IV) is 50 mPa * s or less, and it is more preferable that it is 20 mPa * s or less.
The compound represented by the general formula (IV) can be preferably used as a reaction diluent.

  The addition amount of the compound represented by the general formula (IV) in the photocurable composition is preferably 10% by mass or more from the viewpoint of the viscosity of the composition or the pattern accuracy after curing, and is 15% by mass or more. More preferably, it is particularly preferably 20% by mass or more. On the other hand, from the viewpoint of tackiness after curing and mechanical strength, the addition amount is preferably 95% by mass or less, more preferably 90% by mass or less, and particularly preferably 85% by mass or less.

Although the compound represented by general formula (IV) is illustrated below, it cannot be overemphasized that this invention is not limited to these. Each R ¹ in the following formula has the same meaning as R ¹ in the general formula (IV), and the preferred range is also the same _.

  Compound represented by general formula (V):

(In the general formula (V), R ¹ represents a hydrogen atom, an alkyl group or a halogen atom, X ³ is a single bond or a hydrocarbon group, and the hydrocarbon group contains a hetero atom in its chain. Y ³ represents a substituent having an aromatic group, n ₃ represents an integer of 1 to _3. Ar ₁ represents an aromatic linking group.
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
Y ³ represents a substituent having an aromatic group. As the substituent having an aromatic group, the aromatic group is bonded to the aromatic ring of the general formula (V) through a single bond or a linking group. Is preferred. Preferred examples of the linking group include an alkylene group, a linking group having a hetero atom (preferably —O—, —S—, —C (═O) O—), or a combination thereof. A group consisting of O- and combinations thereof is more preferred. The substituent having an aromatic group is preferably a substituent having a phenyl group. A mode in which the phenyl group is bonded through a single bond or the above linking group is preferable, and a phenyl group, a benzyl group, a phenoxy group, a benzyloxy group, and a phenylthio group are particularly preferable. The molecular weight of Y ³ is preferably a 230 to 350.
n ₃ is preferably 1 or 2, and more preferably 1.
Ar ₁ is preferably a phenylene group or a naphthylene group.

  The addition amount of the compound represented by the general formula (V) in the photocurable composition used in the present invention is preferably 10% by mass or more, more preferably 20% by mass or more, and 30% by mass. The above is particularly preferable. On the other hand, from the viewpoint of tackiness after curing and mechanical strength, the addition amount is preferably 90% by mass or less, more preferably 80% by mass or less, and particularly preferably 70% by mass or less.

Although the compound represented by general formula (V) is illustrated below, it cannot be overemphasized that this invention is not limited to these. R ₁ in the following formula has the same meaning as R ¹ in the general formula (V), and the preferred range is also the same.

  Polyfunctional (meth) acrylate compound represented by general formula (II):

In the formula, Ar ₂ represents an n-valent linking group having an aromatic group. X ₁ and R ¹ are as defined above. n represents 1-3.
Ar ₂ is preferably a linking group having a phenylene group.
n is preferably 1.

The compound represented by the general formula (II) is preferably a compound represented by the general formula (VI) or (VII).
Compound represented by general formula (VI):

(In General Formula (VI), X ⁶ is a (n ₆ +1) -valent linking group, R ¹ is a hydrogen atom, an alkyl group, or a halogen atom, respectively. R ² and R ³ are each substituted. Each of n ₄ and n ₅ is an integer of 0 to _4. n ₆ is 1 or 2, X ⁴ and X ⁵ are each a hydrocarbon group, and the hydrocarbon group is , The chain may contain a linking group containing a heteroatom.)

X ⁶ represents a single bond or a (n ₆ +1) -valent linking group, and preferably an alkylene group, —O—, —S—, —C (═O) O—, or a combination thereof. It is a linking group. The alkylene group is preferably an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms. An unsubstituted alkylene group is preferred.
n ₆ is preferably 1. When n6 is 2, a plurality of R ¹ , X ⁵ and R ² may be the same or different.
X ⁴ and X ⁵ are each preferably an alkylene group containing no linking group, more preferably an alkylene group having 1 to 5 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms, A methylene group is preferred.
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
R ² and R ³ each represent a substituent, preferably an alkyl group, a halogen atom, an alkoxy group, an acyl group, an acyloxy group, an alkoxycarbonyl group, a cyano group, or a nitro group. As an alkyl group, a C1-C8 alkyl group is preferable. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable. As an alkoxy group, a C1-C8 alkoxy group is preferable. As the acyl group, an acyl group having 1 to 8 carbon atoms is preferable. As the acyloxy group, an acyloxy group having 1 to 8 carbon atoms is preferable. As an alkoxycarbonyl group, a C1-C8 alkoxycarbonyl group is preferable.
n ₄ and n ₅ are each an integer of 0 to 4, and when n ₄ or n ₅ is 2 or more, a plurality of R ² and R ³ may be the same or different.

  The compound represented by the general formula (VI) is preferably a compound represented by the following general formula (VIII).

(X ⁶ is an alkylene group, —O—, —S—, and a linking group in which a plurality of these are combined, and R ¹ is a hydrogen atom, an alkyl group, or a halogen atom, respectively.)
R ¹ has the same meaning as R ¹ in the formula, the preferred range is also the same.
If X ⁶ is an alkylene group, preferably an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms. An unsubstituted alkylene group is preferred.
The _{^{X 6, -CH 2 -, -}} CH 2 CH 2 -, - O -, - S- it is preferred.

  The content of the compound represented by the general formula (VI) in the photocurable composition used in the present invention is not particularly limited, but from the viewpoint of the viscosity of the photocurable composition, 1-100 mass% is preferable, 5-70 mass% is more preferable, 10-50 mass% is especially preferable.

Although the compound represented by general formula (VI) is illustrated below, it cannot be overemphasized that this invention is not limited to these. R ¹ in the following formula has the same meaning as R ¹ in the general formula (VI), and the preferable range is also the same, and particularly preferably a hydrogen atom.

  A polymerizable monomer represented by the following general formula (VII):

(In the formula, Ar represents an arylene group which may have a substituent, X represents a single bond or an organic linking group, R ¹ represents a hydrogen atom or a methyl group, and n represents 2 or 3. )

  In the general formula, the arylene group includes a hydrocarbon-based arylene group such as a phenylene group and a naphthylene group; a heteroarylene group in which indole, carbazole and the like are linked groups, preferably a hydrocarbon-based arylene group, More preferred is a phenylene group from the viewpoint of viscosity and etching resistance. The arylene group may have a substituent, and preferred examples of the substituent include an alkyl group, an alkoxy group, a hydroxyl group, a cyano group, an alkoxycarbonyl group, an amide group, and a sulfonamide group.

  Examples of the organic linking group for X include an alkylene group, an arylene group, and an aralkylene group, which may contain a hetero atom in the chain. Among these, an alkylene group and an oxyalkylene group are preferable, and an alkylene group is more preferable. X is particularly preferably a single bond or an alkylene group.

R ¹ is a hydrogen atom or a methyl group, preferably a hydrogen atom.
n is 2 or 3, preferably 2.

  That the polymerizable monomer represented by the general formula (VII) is a polymerizable monomer represented by the following general formula (Ia) or (Ib) reduces the viscosity of the composition. It is preferable from the viewpoint.

(In formula, X < ¹ >, X < ² > represents the alkylene group which may have a single bond or a C1-C3 substituent each independently, and R < ¹ > represents a hydrogen atom or a methyl group.)

In the general formula (Ia), X ¹ is preferably a single bond or a methylene group, and more preferably a methylene group from the viewpoint of viscosity reduction.
A preferred range of the X ² is the same as the preferred range of the X ^1.
Wherein R ¹ is as in formula and R ¹ synonymous, and preferred ranges are also the same.

  When the polymerizable monomer is liquid at 25 ° C., it is preferable that the generation of foreign matters can be suppressed even when the addition amount is increased.

Specific examples of the polymerizable monomer represented by formula (VII) are shown below. R ¹ has the same meaning as R ¹ in the general formula represents a hydrogen atom or a methyl group. The present invention is not limited to these specific examples.

Although the more preferable specific example of the polymerizable monomer which has an aromatic group used with the photocurable composition used by this invention below is given, this invention is not limited to these.
Examples of the polymerizable monomer having an aromatic group include benzyl (meth) acrylate which is unsubstituted or has a substituent on an aromatic ring, phenethyl which is unsubstituted or has a substituent on an aromatic ring ( (Meth) acrylate, unsubstituted or substituted phenoxyethyl (meth) acrylate having an aromatic ring, 1- or 2-naphthyl (meth) acrylate having an unsubstituted or substituted aromatic ring, 1- or 2-naphthylmethyl (meth) acrylate having a substituent on unsubstituted or aromatic ring, 1- or 2-naphthylethyl (meth) having a substituent on unsubstituted or aromatic ring Acrylate, 1- or 2-naphthoxyethyl (meth) acrylate, resorcinol di (meth) acrylate, m-xylylene di (meth) acrylate, naphthalene di (meth) acrylate Ethoxylated bisphenol A diacrylate is preferred, benzyl acrylate having a substituent on the unsubstituted or an aromatic ring, 1 or 2-naphthylmethyl acrylate, m- xylylene acrylate, are more preferred.

  As a particularly preferred embodiment, a polymerizable monomer containing an aromatic group (preferably a phenyl group, a naphthyl group, more preferably a naphthyl group) as the second polymerizable monomer and having one (meth) acrylate group. Preferably the compound of the general formula (I) is 0 to 80% by mass, preferably 20 to 70% by mass in the second polymerizable monomer, and an aromatic group (preferably phenyl group, naphthyl group, more preferably A polymerizable monomer containing a phenyl group) and having two (meth) acrylate groups, preferably the compound of the general formula (II) is 20 to 100% by mass in the second polymerizable monomer, preferably 30 to 80% by mass is contained.

  As the content of the second polymerizable monomer described above, the preferred content of the second polymerizable monomer also varies depending on the content of the first polymerizable monomer (Ax) in the present invention. For example, the total polymerizable monomer of the present invention may contain 0 to 99.9% by mass, preferably 50 to 99.8% by mass, and more preferably 90 to 99.5% by mass. It is more preferable.

  Next, a preferred blend form of the first polymerizable monomer (Ax) and the second polymerizable monomer in the present invention will be described.

The monofunctional polymerizable monomer is usually used as a reactive diluent and has an effect of lowering the viscosity of the curable composition of the present invention, and is 15 mass based on the total amount of the polymerizable monomer. % Or more, preferably 20 to 90% by mass, more preferably 25 to 85% by mass, and particularly preferably 30 to 80% by mass.
The monomer having two polymerizable reactive groups (bifunctional polymerizable monomer) is preferably 90% by mass or less, more preferably 80% by mass or less, and particularly preferably 70% by mass of the total polymerizable monomer. It is added in the following range.
The ratio of the monofunctional and bifunctional polymerizable monomers is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, and particularly preferably 50 to 90% by mass of the total polymerizable monomer. Added.

  The ratio of the polyfunctional polymerizable monomer having 3 or more unsaturated bond-containing groups is preferably 50% by mass or less, more preferably 30% by mass or less, and particularly preferably 10% by mass of the total polymerizable monomer. % Is added in a range of not more than%. Since the viscosity of a composition can be lowered | hung by making the ratio of the polymerizable monomer which has 3 or more polymerizable reactive groups into 80 mass% or less, it is preferable.

(Photopolymerization initiator (B))
The curable composition of the present invention contains a photopolymerization initiator. As the photopolymerization initiator used in the present invention, any compound can be used as long as it is a compound that generates an active species capable of polymerizing the above polymerizable monomer by light irradiation. As the photopolymerization initiator, a radical polymerization initiator and a cationic polymerization initiator are preferable, and a radical polymerization initiator is more preferable. In the present invention, a plurality of photopolymerization initiators may be used in combination.

Content of the photoinitiator used for this invention is 0.01-15 mass% in all the compositions except a solvent, for example, Preferably it is 0.1-12 mass%, More preferably, it is 0. 2 to 7% by mass. When using 2 or more types of photoinitiators, the total amount becomes the said range.
When the content of the photopolymerization initiator is 0.01% by mass or more, the sensitivity (fast curability), resolution, line edge roughness, and coating strength tend to be improved, which is preferable. On the other hand, when the content of the photopolymerization initiator is 15% by mass or less, light transmittance, colorability, handleability and the like tend to be improved, which is preferable.

As the radical photopolymerization initiator used in the present invention, for example, a commercially available initiator can be used. As these examples, for example, those described in paragraph No. 0091 of JP-A No. 2008-105414 can be preferably used. Among these, acetophenone compounds, acylphosphine oxide compounds, and oxime ester compounds are preferred from the viewpoints of curing sensitivity and absorption characteristics.
Preferred examples of the acetophenone compound include hydroxyacetophenone compounds, dialkoxyacetophenone compounds, and aminoacetophenone compounds. Irgacure (R) 2959 (1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one, preferably available from BASF as a hydroxyacetophenone compound, Irgacure® 184 (1-hydroxycyclohexyl phenyl ketone), Irgacure® 500 (1-hydroxycyclohexyl phenyl ketone, benzophenone), Darocur® 1173 (2-hydroxy-2-methyl-1-phenyl) -1-propan-1-one).
The dialkoxyacetophenone compound is preferably Irgacure (registered trademark) 651 (2,2-dimethoxy-1,2-diphenylethane-1-one) available from BASF.
As the aminoacetophenone compound, Irgacure (registered trademark) 369 (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1), Irgacure (registered trademark) 379 (available from BASF Corporation) is preferable. EG) (2-dimethylamino-2- (4methylbenzyl) -1- (4-morpholin-4-ylphenyl) butan-1-one, Irgacure® 907 (2-methyl-1 [4- Methylthiophenyl] -2-morpholinopropan-1-one.
As the acylphosphine oxide-based compound, preferably Irgacure (registered trademark) 819 (bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, Irgacure (registered trademark) 1800 (bis (2, 6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, Lucirin TPO (2,4,6-trimethylbenzoyldiphenylphosphine oxide) available from BASF, Lucirin TPO-L (2,4,4) 6-trimethylbenzoylphenylethoxyphosphine oxide).
Irgacure (registered trademark) OXE01 (1,2-octanedione, 1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime), Irgacure (registered trademark), preferably available from BASF as an oxime ester compound Trademark) OXE02 (ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime).
The cationic photopolymerization initiator used in the present invention is preferably a sulfonium salt compound, an iodonium salt compound, an oxime sulfonate compound, and the like, and 4-methylphenyl [4- (1-methylethyl) phenyliodonium tetrakis (pentafluorophenyl) Examples include borate (PI2074 manufactured by Rhodea), 4-methylphenyl [4- (2-methylpropyl) phenyliodonium hexafluorophosphate (IRGACURE250 manufactured by BASF), IRGACURE PAG103, 108, 121, 203 (manufactured by Ciba). .

  In the present invention, “light” includes not only light having a wavelength in the ultraviolet, near-ultraviolet, far-ultraviolet, visible, infrared, etc., and electromagnetic waves but also radiation. Examples of the radiation include microwaves, electron beams, EUV, and X-rays. Laser light such as a 248 nm excimer laser, a 193 nm excimer laser, and a 172 nm excimer laser can also be used. The light may be monochromatic light (single wavelength light) that has passed through an optical filter, or may be light with a plurality of different wavelengths (composite light). The exposure can be multiple exposure, and the entire surface can be exposed after forming a pattern for the purpose of increasing the film strength and etching resistance.

(Other ingredients)
The curable composition of the present invention includes a surfactant, an antioxidant, and a solvent as long as the effects of the present invention are not impaired according to various purposes in addition to the above-described polymerizable monomer and photopolymerization initiator. Other components such as a polymer component, a pigment, and a dye may be included. The curable composition of the present invention preferably contains at least one selected from a polymerization inhibitor, a surfactant, and an antioxidant.

-Surfactant-
The curable composition of the present invention preferably contains a surfactant. The content of the surfactant used in the present invention is, for example, 0.001 to 5% by mass, preferably 0.002 to 4% by mass, and more preferably 0.005 to 5% in the entire composition. 3% by mass. When using 2 or more types of surfactant, the total amount becomes the said range. When the surfactant is in the range of 0.001 to 5% by mass in the composition, the effect of coating uniformity is good, and deterioration of mold transfer characteristics due to excessive surfactant is unlikely to occur.

The surfactant is preferably a nonionic surfactant, and preferably contains at least one of a fluorine-based surfactant, a Si-based surfactant, and a fluorine / Si-based surfactant. It is more preferable to include both of the Si-based surfactant or the fluorine / Si-based surfactant, and it is most preferable to include the fluorine / Si-based surfactant. The fluorine-based surfactant and the Si-based surfactant are preferably nonionic surfactants.
Here, the “fluorine / Si-based surfactant” refers to one having both the requirements of both a fluorine-based surfactant and a Si-based surfactant.
By using such a surfactant, a silicon wafer for manufacturing a semiconductor element, a glass square substrate for manufacturing a liquid crystal element, a chromium film, a molybdenum film, a molybdenum alloy film, a tantalum film, a tantalum alloy film, a silicon nitride film, Striation that occurs when the curable composition for imprinting of the present invention is applied to a substrate on which various films such as an amorphous silicone film, an indium oxide (ITO) film doped with tin oxide, and a tin oxide film are formed. In addition, it is possible to solve the problem of poor application such as a scale-like pattern (unevenness of drying of the resist film). In addition, the fluidity of the composition of the present invention into the cavity of the mold recess is improved, the peelability between the mold and the resist is improved, the adhesion between the resist and the substrate is improved, the viscosity of the composition is decreased, etc. Is possible. In particular, the curable composition for imprints of the present invention can significantly improve the coating uniformity by adding the surfactant, and the coating using a spin coater or slit scan coater does not depend on the substrate size. Good applicability is obtained.

Examples of nonionic fluorosurfactants that can be used in the present invention include trade names Florard FC-430 and FC-431 (manufactured by Sumitomo 3M Limited), trade names Surflon S-382 (Asahi Glass ( EFTOP EF-122A, 122B, 122C, EF-121, EF-126, EF-127, MF-100 (manufactured by Tochem Products), trade names PF-636, PF-6320, PF -656, PF-6520 (both OMNOVA Solutions, Inc.), trade names FT250, FT251, DFX18 (all manufactured by Neos Co., Ltd.), trade names Unidyne DS-401, DS-403, DS-451 ( All are manufactured by Daikin Industries, Ltd.) and trade names Megafuk 171, 172, 173, 178K 178A, F780F (all manufactured by Dainippon Ink & Chemicals Co., Ltd.) and the like.
Examples of the nonionic Si-based surfactant include trade name SI-10 series (manufactured by Takemoto Yushi Co., Ltd.), MegaFac Paintad 31 (manufactured by Dainippon Ink & Chemicals, Inc.), KP -341 (manufactured by Shin-Etsu Chemical Co., Ltd.).
Examples of the fluorine / Si surfactant include trade names X-70-090, X-70-091, X-70-092, X-70-093 (all Shin-Etsu Chemical Co., Ltd. )), And trade names Megafuk R-08 and XRB-4 (both manufactured by Dainippon Ink & Chemicals, Inc.).

-Antioxidant-
Furthermore, the curable composition of the present invention preferably contains a known antioxidant. Content of the antioxidant used for this invention is 0.01-10 mass% with respect to a polymerizable monomer, for example, Preferably it is 0.2-5 mass%. When two or more kinds of antioxidants are used, the total amount is within the above range.
The antioxidant suppresses fading caused by heat or light irradiation and fading caused by various oxidizing gases such as ozone, active oxygen, NO _x , and SO _x (X is an integer). In particular, in the present invention, by adding an antioxidant, there is an advantage that coloring of a cured film can be prevented and a reduction in film thickness due to decomposition can be reduced. Examples of such antioxidants include hydrazides, hindered amine antioxidants, nitrogen-containing heterocyclic mercapto compounds, thioether antioxidants, hindered phenol antioxidants, ascorbic acids, zinc sulfate, thiocyanates, Examples include thiourea derivatives, sugars, nitrites, sulfites, thiosulfates, hydroxylamine derivatives, and the like. Among these, hindered phenol antioxidants and thioether antioxidants are particularly preferable from the viewpoint of coloring the cured film and reducing the film thickness.

  Commercially available products of the antioxidant include trade names Irganox 1010, 1035, 1076, and 1222 (above, manufactured by Ciba Geigy Co., Ltd.), trade names Antigene P, 3C, FR, Sumilyzer S, and Sumilyzer GA80 (Sumitomo Chemical Co., Ltd.). Product name) ADK STAB AO70, AO80, AO503 (manufactured by ADEKA Corporation) and the like. These may be used alone or in combination.

-Polymerization inhibitor-
Furthermore, the curable composition of the present invention preferably contains a polymerization inhibitor. By including a polymerization inhibitor, it tends to be possible to suppress changes in viscosity over time, generation of foreign matters, and deterioration of pattern formation. As content of a polymerization inhibitor, it is 0.001-1 mass% with respect to all the polymerizable monomers, More preferably, it is 0.005-0.5 mass%, More preferably, it is 0.008-0. 05% by mass. By blending an appropriate amount of the polymerization inhibitor, it is possible to suppress a change in viscosity over time while maintaining high curing sensitivity. The polymerization inhibitor may be contained in advance in the polymerizable monomer to be used, or may be further added to the composition.
Preferred polymerization inhibitors that can be used in the present invention include hydroquinone, p-methoxyphenol, di-tert-butyl-p-cresol, pyrogallol, tert-butylcatechol, benzoquinone, 4,4′-thiobis (3-methyl-6). -Tert-butylphenol), 2,2'-methylenebis (4-methyl-6-tert-butylphenol), N-nitrosophenylhydroxyamine cerium salt, phenothiazine, phenoxazine, 4-methoxynaphthol, 2,2,6 , 6-Tetramethylpiperidine-1-oxyl free radical, 2,2,6,6-tetramethylpiperidine, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, nitrobenzene, dimethyl And aniline. Particularly effective in the absence of oxygen, phenothiazine, 4-methoxynaphthol, 2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 2,2,6,6-tetramethylpiperidine, 4- Hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical is preferred.

-Solvent-
A solvent can be used for the curable composition of this invention as needed. A preferable solvent is a solvent having a boiling point of 80 to 200 ° C. at normal pressure. Any solvent can be used as long as it can dissolve the composition, but a solvent having any one or more of an ester structure, a ketone structure, a hydroxyl group, and an ether structure is preferable. Specifically, preferred solvents are propylene glycol monomethyl ether acetate, cyclohexanone, 2-heptanone, gamma butyrolactone, propylene glycol monomethyl ether, ethyl lactate alone or a mixed solvent, and a solvent containing propylene glycol monomethyl ether acetate. Most preferable from the viewpoint of coating uniformity.
The content of the solvent in the composition of the present invention is optimally adjusted depending on the viscosity of the components excluding the solvent, coating properties, and the desired film thickness. From the viewpoint of improving coating properties, 99% by mass in the total composition. % Or less can be added. When applying the composition of this invention on a board | substrate by an inkjet method, it is preferable that a solvent does not contain substantially (for example, 3 mass% or less). On the other hand, when forming a pattern having a film thickness of 500 nm or less by a method such as spin coating, it may be included in the range of 20 to 99% by mass, preferably 40 to 99% by mass, particularly preferably 70 to 98% by mass. .

-Polymer component-
In the composition of the present invention, for the purpose of further increasing the crosslinking density, a polyfunctional oligomer having a molecular weight higher than that of the polyfunctional second polymerizable monomer is blended within a range that achieves the object of the present invention. You can also. Examples of the polyfunctional oligomer having photoradical polymerizability include various acrylate oligomers such as polyester acrylate, urethane acrylate, polyether acrylate, and epoxy acrylate. The addition amount of the oligomer component is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, further preferably 0 to 10% by mass, and most preferably 0 to 5% by mass with respect to the component excluding the solvent of the composition. %.
The curable composition of the present invention may further contain a polymer component from the viewpoint of improving dry etching resistance, imprint suitability, curability and the like. The polymer component is preferably a polymer having a polymerizable functional group in the side chain. As a weight average molecular weight of the said polymer component, 2000-100000 are preferable from a compatible viewpoint with a polymerizable monomer, and 5000-50000 are more preferable. The addition amount of the polymer component is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, still more preferably 0 to 10% by mass, and most preferably 2% by mass or less, relative to the component excluding the solvent of the composition. It is. In the composition except for the solvent in the composition of the present invention, if the content of the compound having a molecular weight of 2000 or more is 30% by mass or less, the pattern forming property is improved. It is preferable not to contain a resin component except for an agent and a trace amount of additives.

  In addition to the above components, the curable composition of the present invention may include a release agent, a silane coupling agent, an ultraviolet absorber, a light stabilizer, an antiaging agent, a plasticizer, an adhesion promoter, and a thermal polymerization initiator. , Colorants, elastomer particles, photoacid growth agents, photobase generators, basic compounds, flow regulators, antifoaming agents, dispersants, and the like may be added.

  The curable composition of the present invention can be prepared by mixing the above-described components. Mixing and dissolution of the curable composition is usually performed in the range of 0 ° C to 100 ° C. Moreover, after mixing each said component, it is preferable to filter with a filter with the hole diameter of 0.003 micrometer-5.0 micrometers, for example. Filtration may be performed in multiple stages or repeated many times. Moreover, the filtered liquid can be refiltered. The material of the filter used for filtration may be polyethylene resin, polypropylene resin, fluorine resin, nylon resin or the like, but is not particularly limited.

  In the curable composition of the present invention, the viscosity of the mixed liquid of all components excluding the solvent is preferably 100 mPa · s or less, more preferably 1 to 70 mPa · s, still more preferably 2 to 50 mPa · s, most preferably 3 to 30 mPa · s.

[Pattern formation method]
Next, the formation method of the pattern (especially fine uneven | corrugated pattern) using the curable composition for imprints of this invention is demonstrated. In the pattern forming method of the present invention, the step of forming the pattern forming layer by placing the curable composition for imprints of the present invention on a substrate or a support (base material), and pressing the mold on the surface of the pattern forming layer A fine uneven | corrugated pattern can be formed by hardening the composition of this invention through the process to perform and the process of irradiating the said pattern formation layer with light.
Here, the curable composition for imprints of the present invention is preferably further heated and cured after light irradiation. Specifically, a layer (pattern forming layer) comprising at least a pattern forming layer comprising the composition of the present invention on a base material (substrate or support) and drying as necessary. To form a pattern receptor (with a pattern-forming layer provided on the substrate), press the mold against the surface of the pattern-receiving layer of the pattern receptor, and transfer the mold pattern. The concavo-convex pattern forming layer is cured by light irradiation. The optical imprint lithography according to the pattern forming method of the present invention can be laminated and multiple patterned, and can be used in combination with ordinary thermal imprint.

  The curable composition for imprints of the present invention can form a fine pattern with low cost and high accuracy by an optical nanoimprint method. For this reason, what was formed using the conventional photolithographic technique can be formed with further high precision and low cost. For example, the composition of the present invention is applied to a substrate or a support, and a layer comprising the composition is exposed, cured, and dried (baked) as necessary, thereby being used for a liquid crystal display (LCD), It can also be applied as a permanent film such as an overcoat layer or an insulating film, an etching resist for a semiconductor integrated circuit, a recording material, or a flat panel display. In particular, the pattern formed using the curable composition for imprints of the present invention is excellent in etching property, and can be preferably used as an etching resist for dry etching using fluorocarbon or the like.

  In permanent films (resist for structural members) used in liquid crystal displays (LCDs) and resists used in substrate processing of electronic materials, ions of metals or organic substances in the resist are used so as not to hinder the operation of the product. It is desirable to avoid contamination with sexual impurities as much as possible. For this reason, the concentration of the ionic impurities of the metal or organic substance in the curable composition for imprints of the present invention is preferably 1000 ppm or less, desirably 10 ppm or less, more preferably 100 ppb or less.

Hereinafter, a pattern forming method (pattern transfer method) using the curable composition for imprints of the present invention will be specifically described.
In the pattern forming method of the present invention, first, a pattern forming layer is formed by applying the composition of the present invention on a substrate.
As a method for applying the curable composition for imprints of the present invention onto a substrate, a generally well-known application method can be adopted.
As an application method of the present invention, for example, dip coating method, air knife coating method, curtain coating method, wire bar coating method, gravure coating method, extrusion coating method, spin coating method, slit scanning method, ink jet method, etc. A coating film or droplets can be applied onto the substrate, and it is preferable to use an ink jet method. Moreover, although the film thickness of the pattern formation layer which consists of a composition of this invention changes with uses to be used, it is about 0.03 micrometer-30 micrometers. Further, the composition of the present invention may be applied by multiple coating. In the method of installing droplets on a substrate by an inkjet method or the like, the amount of droplets is preferably about 1 pl to 20 pl, and the droplets are preferably arranged on the substrate at intervals. Furthermore, you may form other organic layers, such as a planarization layer, for example between a base material and the pattern formation layer which consists of a composition of this invention. Thereby, since the pattern formation layer and the substrate are not in direct contact with each other, it is possible to prevent adhesion of dust to the substrate, damage to the substrate and the like. In addition, the pattern formed with the composition of this invention is excellent in adhesiveness with an organic layer, even when it is a case where an organic layer is provided on a base material.

  The base material (substrate or support) for applying the curable composition for imprints of the present invention can be selected depending on various applications, for example, quartz, glass, optical film, ceramic material, vapor deposition film, magnetic property. Film, reflective film, metal substrate such as Ni, Cu, Cr, Fe, paper, polymer substrate such as SOG (Spin On Glass), polyester film, polycarbonate film, polyimide film, TFT array substrate, PDP electrode plate, glass, There are no particular restrictions on transparent plastic substrates, conductive substrates such as ITO or metal, insulating substrates, semiconductor fabrication substrates such as silicon, silicon nitride, polysilicon, silicon oxide, and amorphous silicon. Further, the shape of the substrate is not particularly limited, and may be a plate shape or a roll shape. In addition, as described later, a light transmissive or non-light transmissive material can be selected as the base material depending on the combination with the mold or the like.

Next, in the pattern forming method of the present invention, a mold is pressed against the surface of the pattern forming layer in order to transfer the pattern to the pattern forming layer. Thereby, the fine pattern previously formed on the pressing surface of the mold can be transferred to the pattern forming layer.
Alternatively, the composition of the present invention may be applied to a mold having a pattern and the substrate may be pressed.
The molding material that can be used in the present invention will be described. In optical nanoimprint lithography using the composition of the present invention, a light transmissive material is selected as at least one of a molding material and / or a base material. In optical imprint lithography applied to the present invention, a curable composition of the present invention is applied onto a substrate to form a pattern forming layer, a light-transmitting mold is pressed against this surface, and the back surface of the mold Then, the pattern forming layer is cured by irradiating light. Moreover, a curable composition is apply | coated on a transparent base material, a mold is pressed, light can be irradiated from the back surface of a base material, and a curable composition can also be hardened.
The light irradiation may be performed with the mold attached or after the mold is peeled off. In the present invention, the light irradiation is preferably performed with the mold in close contact.

As the mold that can be used in the present invention, a mold having a pattern to be transferred is used. The pattern on the mold can be formed according to the desired processing accuracy by, for example, photolithography, electron beam drawing, or the like, but the mold pattern forming method is not particularly limited in the present invention.
The light-transmitting mold material used in the present invention is not particularly limited as long as it has predetermined strength and durability. Specifically, a light transparent resin such as glass, quartz, PMMA, and polycarbonate resin, a transparent metal vapor-deposited film, a flexible film such as polydimethylsiloxane, a photocured film, and a metal film are exemplified.

  In the present invention, the non-light-transmitting mold material used when a light-transmitting substrate is used is not particularly limited as long as it has a predetermined strength. Specific examples include ceramic materials, vapor deposition films, magnetic films, reflective films, metal substrates such as Ni, Cu, Cr, and Fe, and substrates such as SiC, silicon, silicon nitride, polysilicon, silicon oxide, and amorphous silicon. There are no particular restrictions. Further, the shape of the mold is not particularly limited, and may be either a plate mold or a roll mold. The roll mold is applied particularly when continuous transfer productivity is required.

  The mold used in the pattern forming method of the present invention may be a mold that has been subjected to a release treatment in order to improve the peelability between the curable composition and the mold surface. As such a mold, those treated with a silane coupling agent such as silicon-based or fluorine-based, for example, OPTOOL DSX manufactured by Daikin Industries, Ltd., Novec EGC-1720 manufactured by Sumitomo 3M Limited, etc. Commercially available release agents can also be suitably used.

  When performing photoimprint lithography using the composition of the present invention, it is usually preferable to perform the mold pressure at 10 atm or less in the pattern forming method of the present invention. By setting the mold pressure to 10 atm or less, the mold and the substrate are hardly deformed and the pattern accuracy tends to be improved. Further, it is preferable from the viewpoint that the apparatus can be reduced because the pressure is low. As the mold pressure, it is preferable to select a region in which the uniformity of mold transfer can be ensured within a range in which the residual film of the curable composition on the mold convex portion is reduced.

In the pattern forming method of the present invention, the irradiation amount of the light irradiation in the step of irradiating the pattern forming layer may be sufficiently larger than the irradiation amount necessary for curing. The irradiation amount necessary for curing is appropriately determined by examining the consumption of unsaturated bonds of the curable composition and the tackiness of the cured film.
When the curable composition for imprints according to the present invention is used, the curable composition for imprints is applied onto a substrate, and then left under reduced pressure (for example, 0.01 MPa or less) or left for 1 minute or longer. It is possible to maintain good imprintability even if the mold is pressed and exposed after elapse of time after application to the substrate in a situation where volatilization of the liquid and contamination from the environment are likely to occur. The imprintability can be maintained particularly well when the time between the application and pressing of the mold is 1 to 20 minutes. This effect is highly significant when applied by the ink jet method. Moreover, even if the time from the pressing of the mold to the exposure is shortened, it is possible to maintain good imprintability with good mold filling. That is, the curable composition must be properly filled into the mold between the time the mold is pressed against the cured composition and exposed, but if the filling property is poor, it takes time to fill, If time is shortened, it may harden | cure in the state which cannot be filled. However, in the present invention, such a problem can be suppressed, so that the time between the pressing of the mold and the exposure is, for example, less than 60 seconds, preferably less than 30 seconds, more preferably less than 10 seconds. In addition, imprintability can be maintained.
In the photoimprint lithography applied to the present invention, the substrate temperature at the time of light irradiation is usually room temperature, but the light irradiation may be performed while heating in order to increase the reactivity. As a pre-stage of light irradiation, if it is in a vacuum state, it is effective in preventing bubbles from being mixed, suppressing the decrease in reactivity due to oxygen mixing, and improving the adhesion between the mold and the curable composition. May be. Moreover, the preferable vacuum degree at the time of light irradiation in the pattern formation method of this invention is the range of 10 ^<-1 > Pa to a normal pressure.

  The light used for curing the curable composition of the present invention is not particularly limited, and examples thereof include high energy ionizing radiation, light having a wavelength in the region of near ultraviolet, far ultraviolet, visible, infrared, or radiation. . As the high-energy ionizing radiation source, for example, an electron beam accelerated by an accelerator such as a cockcroft accelerator, a handagraaf accelerator, a linear accelerator, a betatron, or a cyclotron is industrially most conveniently and economically used. However, radiation such as γ rays, X rays, α rays, neutron rays, proton rays emitted from radioisotopes or nuclear reactors can also be used. Examples of the ultraviolet ray source include an ultraviolet fluorescent lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, a carbon arc lamp, and a solar lamp. The radiation includes, for example, microwaves and EUV. Also, laser light used in semiconductor microfabrication such as LED, semiconductor laser light, or 248 nm KrF excimer laser light or 193 nm ArF excimer laser can be suitably used in the present invention. These lights may be monochromatic lights, or may be lights having different wavelengths (mixed lights).

During exposure is preferably in the range of exposure intensity of ^{1mW / cm 2 ~50mW / cm 2} . By setting it to 1 mW / cm ² or more, the exposure time can be shortened, so that productivity is improved. By setting it to 50 mW / cm ² or less, deterioration of the properties of the permanent film due to side reactions can be suppressed. It tends to be preferable. The exposure amount is desirably in the range of 5 mJ / cm ^{2 to} 1000 mJ / cm ² . If it is less than 5 mJ / cm ² , the exposure margin becomes narrow, photocuring becomes insufficient, and problems such as adhesion of unreacted substances to the mold tend to occur. On the other hand, when it exceeds 1000 mJ / cm ² , there is a risk of deterioration of the permanent film due to decomposition of the composition.
Further, during exposure, in order to prevent inhibition of radical polymerization by oxygen, an inert gas such as nitrogen or argon may be flowed to control the oxygen concentration to less than 100 mg / L.

  In the pattern formation method of this invention, after hardening a pattern formation layer by light irradiation, it may include the process of applying the heat | fever to the pattern hardened | cured as needed and further making it harden | cure. As heat which heat-hardens the composition of this invention after light irradiation, 150-280 degreeC is preferable and 200-250 degreeC is more preferable. In addition, the time for applying heat is preferably 5 to 60 minutes, and more preferably 15 to 45 minutes.

[pattern]
As described above, the pattern formed by the pattern forming method of the present invention can be used as a permanent film (resist for a structural member) or an etching resist used in a liquid crystal display (LCD) or the like. In addition, the permanent film is bottled in a container such as a gallon bottle or a coated bottle after manufacture, and is transported and stored. In this case, in order to prevent deterioration, the inside of the container is made of inert nitrogen or argon. It may be replaced. Further, at the time of transportation and storage, the temperature may be normal temperature, but the temperature may be controlled in the range of −20 ° C. to 0 ° C. in order to prevent the permanent film from being altered. Of course, it is preferable to shield from light so that the reaction does not proceed.

The pattern formed by the pattern forming method of the present invention is also useful as an etching resist. When the imprint composition of the present invention is used as an etching resist, first, a silicon wafer or the like on which a thin film such as SiO ₂ is formed as a substrate is used, and the pattern forming method of the present invention is used on the substrate. A nano-order fine pattern is formed. Thereafter, a desired pattern can be formed on the substrate by etching using an etching gas such as hydrogen fluoride in the case of wet etching or CF _{4 in} the case of dry etching. The curable composition of the present invention has particularly good etching resistance against dry etching.

  The present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

(Preparation of curable composition)
A polymerizable monomer and a polymerization initiator shown in the following table are mixed, and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical (manufactured by Tokyo Chemical Industry Co., Ltd.) is further used as a polymerization inhibitor. In addition, it adjusted so that it might become 200 ppm (0.02 mass%) with respect to the gross mass of a polymerizable monomer. This was filtered through a polytetrafluoroethylene filter having a pore size of 0.1 μm to prepare a curable composition.
The table shows the mass ratio.

Comparative compound X-1: Daikin Industries, Ltd., R-1420
X-2: Daikin Industries, Ltd., R-1620
X-3: 2,2,3,3,4,4,5,5-octafluoro-1,6-hexane diacrylate (manufactured by SynQuest Laboratories, Inc.)
X-4: Dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name: KAYARAD DPHA)

<First polymerizable monomer (Ax)>

<Second polymerizable monomer>
R-1: benzyl acrylate (Osaka Organic Chemical Co., Ltd., Biscoat # 160)
R-2: 2-naphthylmethyl acrylate (synthesized in a conventional manner from 2-bromomethylnaphthalene and acrylic acid)
R-3: Ethylene glycol diacrylate (manufactured by Aldrich)
R-4: m-xylylene diacrylate (synthesized in a conventional manner from α, α'-dichloro-m-xylene and acrylic acid)
R-5: Isobornyl acrylate (IBXA, Osaka Organic Chemical Co., Ltd.)
R-6: 3-acryloxypropyltris (trimethylsiloxy) silane (Gelest, SIA0210)
R-7: Tricyclodecane dimethanol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-DCP)

<Photopolymerization initiator>
P-1: 2-hydroxy-2-methyl-1-phenyl-1-propan-1-one (manufactured by BASF, Darocur 1173)
P-2: (2-dimethylamino-2- (4methylbenzyl) -1- (4-morpholin-4-ylphenyl) butan-1-one (Irgacure 379EG, manufactured by BASF)

(Evaluation)
The following evaluation was performed about the obtained curable composition of each Example and a comparative example. The results are shown in the table below.

<Viscosity measurement>
The viscosity was measured at 25 ± 0.2 ° C. using a RE-80L rotational viscometer manufactured by Toki Sangyo Co., Ltd.
<Photocurability of curable composition>
After apply | coating the curable composition prepared above on Si wafer, the mold was not crimped | bonded but exposed by exposure amount 240mJ / cm < ² > in nitrogen atmosphere. All of the obtained exposure films were tack-free and a good cured film was obtained.
<Pencil scratch test (pencil hardness)>
About the obtained hardened | cured material, the pencil scratch test was implemented by the weight of 750g according to JIS5600-5-4. The hardness of the pencil that was not scratched was evaluated. It is better that a harder pencil is not scratched. When used as a display surface member, it is at least H or higher, preferably 3H or higher, more preferably 5H or higher. In particular, those of 6H or higher have high utility value.
<Pattern formation method>
The mold has a rectangular line / space pattern (1/1) with a line width of 30 nm and a groove depth of 60 nm, and the pattern surface is treated with OPTOOL DSX (manufactured by Daikin Industries). The thing which is 2.3 nm was used.

  A pattern was formed under any of the following (Condition 1) to (Condition 3) using the mold.

(Condition 1)
Using an inkjet printer manufactured by FUJIFILM Daimatics, the photocurable composition was discharged on a silicon wafer by controlling the discharge timing so as to form a square array with an interval of 450 μm with a droplet amount of 8 pl per nozzle. . Five minutes after discharge, the mold was placed on this at 25 ° C. and 1 atm. One minute later, exposure was performed from the mold side using a mercury lamp under the condition of 300 mJ / cm ^2. After exposure, the mold was released to obtain a pattern.
(Condition 2)
A pattern was obtained by performing the same operation as in Condition 1 except that the time from placing the mold to exposure was set to 5 seconds.
(Condition 3)
A pattern was obtained by performing the same operation as in Condition 1 except that the environment when placing the mold was reduced to 0.1 atm and the time from placing the mold to exposure was set to 5 seconds.

<Pattern evaluation>
The pattern shape and pattern defect of the obtained pattern were observed with a scanning electron microscope and evaluated as follows.
(Shape evaluation)
A: A rectangular pattern faithful to the mold was obtained.
B: The pattern top was rounded. C: The pattern top was rounded and the pattern height was low.
(Defect assessment)
Pattern defects such as pattern peeling, cracking and crushing were observed.
a: No pattern defect was observed.
b: Defects were found in some of the region patterns, but they were less than 5% of the total pattern area.
c: Pattern defects were observed in a region of 5% or more with respect to the total pattern area.

<Line edge roughness after dry etching (LER)>
The pattern-formed substrate obtained in the pattern formation evaluation under Condition 3 is plasma dry etched with Ar / CF ₄ / O ₂ gas using a dry etcher manufactured by Hitachi High-Technology Co., Ltd. The distance from the reference line where the edge should be in the range of 5 μm in the longitudinal direction was measured by 50 points with a length measurement SEM, the standard deviation was obtained, and 3σ was calculated. The smaller the value, the better the line edge roughness.
<Mold peelability>
Twenty coating films were prepared for each sample by spin coating on a silicon substrate obtained by treating the curable composition prepared above with KBM-5103 (manufactured by Shin-Etsu Chemical Co., Ltd.). The resulting coated film has a rectangular line / space pattern (1/1) having a line width of 100 nm and a groove depth of 150 nm, and the surface of the pattern is treated with a silane coupling agent having a perfluoropolyether structure. Was placed on the nanoimprinting device. The inside of the apparatus was evacuated and then purged with nitrogen to replace the inside of the apparatus with nitrogen. The mold was pressure-bonded to the substrate at 25 ° C. and a pressure of 0.5 MPa, and exposed to this from the back surface of the mold under the condition of 240 mJ / cm ^2. After exposure, the mold was released to obtain a pattern. Using the same mold, pattern transfer was repeated for 20 coating films. The pattern obtained by the 20th transfer was observed with a scanning microscope. Further, whether or not the composition component was attached to the mold used for pattern formation was observed with a scanning electron microscope and an optical microscope to evaluate the peelability.
A: Adhesion of the curable composition to the mold was not recognized at all.
B: Slight adhesion of the curable composition was observed on the mold.
C: Adherence of the curable composition to the mold was clearly recognized.
D: The cured composition adhered to the mold space, and 20 pattern transfers could not be performed normally.

  Examples using the polymerizable composition of the present invention are excellent in pattern shape even when pattern formation is performed under conditions 2 and 3 with high throughput, have few defects, and are excellent in line edge roughness after dry etching. Moreover, the cured film strength is high and the peelability is also excellent. On the other hand, in the comparative example, the performance of any one of the pattern shape, the defect, and the line edge roughness after dry etching is inferior, and the cured film strength and the peelability cannot be compatible.

Claims (9)

A curable composition for imprints containing a polymerizable monomer (A) and a photopolymerization initiator (B), wherein at least one of the following general formulas (A) Curability for imprints containing the first polymerizable monomer (Ax) represented by 1) and a second polymerizable monomer different from the first polymerizable monomer (Ax) Composition.
Formula (1): Rf {-(L) m-Y} n
(In the formula, Rf represents an n-valent group selected from the following f-1 to f-10, n represents an integer of 3 to 6, and L represents an alkylene group having 1 to 10 carbon atoms and 6 to 6 carbon atoms. It is obtained by combining 10 arylene groups, -O-, -S-, -N (R)-, an alkylene group having 1 to 10 carbon atoms and -O-, -S-, or -N (R)-. Or a group obtained by combining an arylene group having 6 to 10 carbon atoms and —O—, —S—, or —N (R) —, wherein R represents a hydrogen atom or an alkyl having 1 to 5 carbon atoms; M represents 0 or 1. Y represents a polymerizable group selected from a (meth) acryloyl group, an allyl group, an α-fluoroacryloyl group, an epoxy group, and —C (O) OCH═CH _2. .)

The curable composition for imprints according to claim 1, wherein the first polymerizable monomer (Ax) is any one of Ax-1 to Ax-13 below.

  The curable composition for imprints according to claim 1 or 2, wherein the viscosity of the mixed liquid of all components excluding the solvent is 100 mPa · s or less.   The other polymerizable monomer different from the first polymerizable monomer (Ax) is an aromatic group, an alicyclic hydrocarbon group, or a (meth) acrylate having an Si atom. The curable composition for imprints according to any one of the above.   The curable composition for imprints according to any one of claims 1 to 4, wherein the first polymerizable monomer (Ax) is contained in an amount of 0.1 to 5% by mass of the total polymerizable monomer component.   Furthermore, the curable composition for imprints of any one of Claims 1-5 containing a polymerization inhibitor.   Applying the curable composition for imprints according to any one of claims 1 to 6 on a substrate to form a pattern forming layer; and pressing a mold on the surface of the pattern forming layer; Irradiating the pattern forming layer with light. A pattern forming method comprising:   The pattern forming method according to claim 7, wherein a method of applying the curable composition for imprints on a substrate is an inkjet method.   The pattern obtained by the pattern formation method of Claim 7 or 8.