TWI643893B - Curable composition for photo-imprints, method for forming pattern, and pattern - Google Patents

Abstract

The present invention provides a hardenable composition for photoimprinting with excellent inkjet ejection accuracy and mold release properties. In particular, a hardenable composition and pattern formation for photoimprinting with excellent stability over time with inkjet ejection accuracy and release characteristics. Methods and patterns.

This curable composition for photoimprint contains a polymerizable compound, a photopolymerization initiator, and a fluorine-containing compound, and the fluorine-containing compound is represented by the following general formula (I); in the general formula (I), Rf ¹ has two The above fluorine-containing fluorine-containing alkyl group having 1 to 6 carbon atoms; R ¹ represents an alkyl group having 1 to 7 carbon atoms or an aryl group having 6 to 8 carbon atoms; m represents an integer of 0 to 2 and n represents 1 to 3 An integer; when n is 2 or 3, Rf ¹ may be different from each other.

Description

Curable composition for photoimprint, pattern forming method, and pattern

The present invention relates to a curable composition for photoimprint. In more detail, optical devices such as semiconductor integrated circuits, flat screens, micro-electro-mechanical systems (MEMS), sensor elements, optical disks, high-density memory disks, diffraction gratings, or embossed holograms, etc. Parts, nano-devices, optical devices, optical films or polarizing elements for the production of flat-panel displays, thin-film transistors, organic transistors, color filters, overcoat layers, pillars, and liquid crystal alignment for liquid crystal displays Photoimprinting for the production of ribs, microlens arrays, immunoassay wafers, DNA separation wafers, microreactors, nano biological devices, optical waveguides, filters, photonic liquid crystals, etc. A curable composition, a pattern forming method, and a pattern.

The embossing method develops the embossing technology that is well known in the production of optical discs. The prototype of a metal mold (commonly referred to as a mold, a stamper, and a template) formed with an uneven pattern is pressed against the photoresist to mechanically deform it and transfer it accurately. Fine pattern technology. Once a mold is manufactured, it is economical because a fine structure such as a nano structure can be simply repeatedly molded, and it is expected to be applied to various fields in recent years.

As the embossing method, a thermal embossing method using a thermoplastic resin as a material to be processed (for example, refer to Non-Patent Document 1) and a light embossing method using a hardening composition (for example, refer to Non-Patent Document 2 and Non-Patent Document) are proposed. 3). The hot stamping method is a resin that is heated to a temperature higher than the glass transition temperature, presses the mold, cools to the temperature below the glass transition temperature, and then releases the mold to transfer the fine structure to the substrate. This method is extremely simple and can also be applied to a variety of resin materials or glass materials.

On the other hand, the photo-imprint method is a method in which a fine pattern is transferred to a photo-hardened object by light-hardening a hardening composition after light irradiation through a light-transmitting mold or a light-transmitting substrate. Since this method can be embossed at room temperature, it can be applied to the field of precision processing of ultra-fine patterns such as the production of semiconductor integrated circuits. Recently, there have been reported new developments such as a nano casting method combining the advantages of the two or an inverse embossing method for making a three-dimensional laminated structure.

In such an imprint method, there are proposals as follows. The first application is that the formed shape (pattern) itself has a function and is used as an element part or a structural member of nanotechnology. Examples include various micron and nanometer optical elements or high-density recording media, optical films, and structural members in flat displays.

The second application is to build a laminated structure by the simultaneous integral molding of microstructure and nanostructure or simple interlayer positioning, and use it in the production of μ-TAS (Micro-Total Analysis System) or biochip.

The third application is to use the formed pattern as a mask to facilitate It is used for processing a substrate by a method such as etching. In such technology, by using high-precision positioning and high integration, instead of the conventional lithography technology, it can be used for the production of high-density semiconductor integrated circuits or the production of transistors for liquid crystal displays. Magnetic processing of the next generation hard disk of patterned media. The progress of imprint methods related to these applications toward practical use has been active in recent years.

Since the imprint method has a step of peeling the mold, its release property has been a problem since the beginning. As an attempt to improve the releasability, a method is known in which a fluorinated monomer molecule or a non-reactive fluorinated compound is contained in the curable composition (Non-Patent Document 4).

On the other hand, the inkjet method has attracted attention for applications in which ultra-fine patterns are formed with a high precision by an imprint method (for example, an etching photoresist for semiconductor substrate processing) (Patent Document 1).

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 2008-502157

[Non-patent literature]

[Non-Patent Document 1] S. Chou et al., Appl. Phys. Lett. 67, 3114 (1995)

[Non-Patent Document 2] J. Haisma et al., J. Vac. Sci. Technol. B 14 (6), 4124 (1996)

[Non-Patent Document 3] M. Colbun et al., Proc. SPIE 3676, 379 (1999)

[Non-Patent Document 4] M. W. Lin et al., J. Micro / Nanolith. MEMS MOEMS 7 (3), 033005 (2008)

Here, since the inkjet method can adjust the coating amount of the hardened composition according to the thickness of the pattern, the thickness unevenness of the residual film can be reduced, and there is an advantage that the pattern quality is excellent. In addition, compared with the spin coating method, the utilization efficiency of the material is high, and it also has the advantage of reducing the production cost or the environmental load. However, if inkjet discharge cannot be performed with high accuracy and stability, problems such as poor filling of the curable composition and uneven thickness of the residual film occur.

On the other hand, the inventors of the present case conducted an intensive review of the conventional technology. As a result, they learned that the non-reactive fluorinated compound described in Non-Patent Document 4 is contained in the hardenable composition for photoimprint. Although there is a certain degree of releasability improvement effect, the inkjet ejection accuracy and the releasability cannot be coexisted, and the inkjet ejection accuracy and the releasability of the hardening composition are significantly deteriorated over time. Further, the curable composition for photoimprint containing a fluorine-containing monomer molecule described in Non-Patent Document 4 is not a level capable of satisfying the mold releasability.

The problem to be solved by the present invention is to solve the above-mentioned problems, and an object thereof is to provide a light-imprinting hardening composition having excellent inkjet discharge accuracy and mold release properties, and in particular, light having excellent stability over time with inkjet discharge accuracy and mold release properties. Hardening composition for imprinting. Another object is to provide a pattern forming method and a pattern.

Under such circumstances, the inventors of the present case conducted an intensive review, and found that by including a specific fluorine-containing compound in the curable composition for photoimprint, the inkjet discharge accuracy and mold release property can be improved, and With the stability of their accompanying time, the present invention has finally been completed.

Specifically, the above-mentioned problem is solved by means of the following solution <1>, and more preferably by means of <2> to <15>.

<1> A curable composition for photoimprint, which contains a polymerizable compound, a photopolymerization initiator, and a fluorine-containing compound, and the fluorine-containing compound is represented by the following general formula (I);

In the general formula (I), Rf ¹ represents a fluorine-containing alkyl group having 1 to 6 carbon atoms having 2 or more fluorine atoms; R ¹ represents an alkyl group having 1 to 7 carbon atoms or an aryl group having 6 to 8 carbon atoms; m represents an integer from 0 to 2, and n represents an integer from 1 to 3. When n represents 2 or 3, Rf ¹ may be different from each other.

<2> The curable composition for photoimprinting as described in <1>, which contains 1 to 5% by mass of a fluorine-containing compound with respect to all components other than the solvent.

<3> The curable composition for photoimprinting according to <1> or <2>, wherein in the general formula (I), Rf ¹ is a perfluoroalkyl group having 4 to 6 carbon atoms.

<4> The curable composition for photoimprinting according to any one of <1> to <3>, wherein in the general formula (I), R ¹ is an alkyl group having 1 to 7 carbon atoms.

<5> The curable composition for photoimprinting according to any one of <1> to <4>, wherein the polymerizable compound is a (meth) acrylate compound.

<6> The curable composition for photoimprinting according to any one of <1> to <5>, wherein the polymerizable compound contains 40 to 100% by mass of 2 (a) (Meth) acrylate polymerizable compound.

<7> The curable composition for photoimprinting according to <6>, wherein the polymerizable compound contains 10 to 45% by mass of a polymerizable compound having one (meth) acrylate group relative to the total polymerizable compound. Compound.

<8> The curable composition for photoimprinting as described in any one of <1> to <7>, wherein the curable composition for photoimprint further contains a non-polymeric polymer having a polyalkylene glycol structure. Sexual compounds.

<9> The curable composition for photoimprinting according to <8>, wherein the non-polymerizable compound having a polyalkylene glycol structure is represented by the following general formula (II);

In the general formula (II), Rf ² and Rf ³ each independently represent a fluorine-containing alkyl group having 1 to 6 carbon atoms having 2 or more fluorine atoms; p ¹ and p ² each independently represent an integer of 1 to 3, q ¹ and q ² each independently represent an integer of 0 to 2, r represents an integer of 2 to 4, and s represents 6 to 20.

<10> The curable composition for photoimprinting according to <8> or <9>, wherein the mass ratio of the fluorine-containing compound represented by the general formula (I) to the non-polymerizable compound having a polyalkylene glycol structure is 1: 5 ~ 5: 5.

<11> The curable composition for light imprinting according to any one of <1> to <10>, wherein the curable composition for light imprint does not substantially contain Solvent.

<12> The hardenable composition for light imprinting according to any one of <1> to <11>, wherein the hardenable composition for light imprinting has a viscosity of 15 mPa at 23 ° C. s or less and the surface tension is 25 ~ 35mN / m.

<13> A pattern forming method comprising applying a curable composition for photoimprint according to any one of <1> to <12> on a substrate or a mold having a pattern, and using the mold and the substrate The light is irradiated while the hardenable composition for photoimprint is sandwiched between the substrates.

<14> The pattern forming method according to <13>, wherein the method of applying the curable composition for photoimprint on a substrate or a mold having a pattern is an inkjet method.

<15> A pattern obtained by the pattern forming method described in <13> or <14>.

According to the present invention, it is possible to provide a hardenable composition for photoimprinting which is excellent in inkjet ejection accuracy and releasability. In particular, it is possible to provide a hardenability for photoimprinting which is excellent in stability over time with inkjet ejection accuracy and release characteristics.组合 物。 Composition. In addition, a pattern forming method and a pattern can be provided.

[Form of Implementing Invention]

Hereinafter, the content of the present invention will be described in detail. The description of the constituent elements described below is based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment. this The so-called "~" in the document description is used to include the numerical value described before and after it as a lower limit value and an upper limit value.

In the description of this case, "(meth) acrylate" means acrylate and methacrylate, "(meth) acryl" means acrylic and methacrylic acid, and "(meth) acryl" refers to acryl and Methacrylfluorenyl. In the present specification, "monomer" is synonymous with "monomer molecule". The single system in the present invention is distinguished from oligomers and polymers, and refers to a compound having a weight average molecular weight of less than 1,000. In the description of this case, "functional group" refers to a group participating in a polymerization reaction. The term "imprint" as used in the present invention preferably refers to a pattern transfer with a size of 1 nm to 100 μm, and more preferably refers to a pattern transfer with a size of 10 nm to 1 μm (nano imprint).

In the description of this case, "(meth) acrylate" means acrylate and methacrylate, "(meth) acryl" means acrylic and methacrylic acid, and "(meth) acryl" refers to acryl and Methacrylfluorenyl. In the present specification, "monomer" is synonymous with "monomer molecule". Single system is different from oligomers and polymers, and refers to compounds with a weight average molecular weight of less than 1,000. In the description of this case, "functional group" refers to a group participating in a polymerization reaction. The term "imprint" as used in the present invention preferably refers to a pattern transfer with a size of 1 nm to 100 μm, and more preferably refers to a pattern transfer with a size of 10 nm to 1 μm (nano imprint).

In the description of the radical (atomic group) in the description of the present case, the descriptions that are not substituted or unsubstituted include those without a substituent and those with a substituent. For example, the so-called "alkyl group" includes not only an alkyl group (unsubstituted alkyl group) having no substituent, but also an alkyl group (substituted alkyl group) having a substituent.

Furthermore, in the description of this case, "light" means not only light or electromagnetic waves with a wavelength in the range of ultraviolet, near ultraviolet, far ultraviolet, visible, infrared, etc., but also includes radiation. The radiation includes, for example, microwaves, electron beams, EUV, and X-rays. Alternatively, laser light such as a 248 nm excimer laser, a 193 nm excimer laser, or a 172 nm excimer laser may be used. These types of light may be monochromatic light (single-wavelength light) that has passed through a filter, or plural kinds of light (composite light) having different wavelengths.

In the specification of the present case, the term “all solid components” refers to the total mass of the components after removing the solvent from the entire composition of the composition.

<The curable composition for photoimprint of the present invention>

The curable composition for photoimprint of the present invention (hereinafter sometimes referred to simply as "curable composition of the present invention" or "composition of the present invention") contains a polymerizable compound (A) and a photopolymerization initiator (B) a fluorine-containing compound (C) represented by the following general formula (I);

In the general formula (I), Rf ¹ represents a fluorine-containing alkyl group having 1 to 6 carbon atoms having 2 or more fluorine atoms; R ¹ represents an alkyl group having 1 to 7 carbon atoms or an aryl group having 6 to 8 carbon atoms; m represents an integer from 0 to 2, and n represents an integer from 1 to 3. When n represents 2 or 3, Rf ¹ may be different from each other.

According to the present invention, it is possible to provide a hardenable composition for photoimprinting which is excellent in inkjet ejection accuracy and releasability, and particularly a hardenable composition for photoimprinting which is excellent in stability over time with inkjet ejection accuracy and release characteristics. . Although the mechanism is not clear, the carbon atom adjacent to Rf ¹ in the general formula (I) does not have a fluorine atom, and R ¹ in the general formula (I) is an alkyl group having 1 to 7 carbon atoms or 6 carbon atoms. ~ 8 aryl group, which can inhibit the hydrolysis of fluorinated compounds, and can improve the stability of inkjet discharge accuracy and release time with time.

<Polymerizable compound (A)>

The polymerizable compound used in the curable composition of the present invention is not particularly limited as long as it does not depart from the gist of the present invention, and examples thereof include a polymerizable unsaturated group having 1 to 6 groups containing an ethylenically unsaturated bond. Monomers; epoxy compounds, oxetane compounds; vinyl ether compounds; styrene derivatives; allyl ether or butenyl ether. Specific examples of the polymerizable compound (A) include those described in paragraph numbers 0020 to 0098 of Japanese Patent Application Laid-Open No. 2011-231308, and the contents are incorporated into the specification of the present application.

Specific examples of the polymerizable unsaturated monomer having one ethylenically unsaturated bond-containing group include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and N- Vinyl pyrrolidone, 2-propenyloxyethyl phthalate, 2-propenyloxy 2-hydroxyethyl phthalate, 2-propenyloxyethyl hexahydroxylbenzene Acid ester, 2-propenyloxypropyl phthalate, 2-ethyl-2-butylpropanediol acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylhexylcarbidine Alcohol (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth) acrylate- 4-hydroxybutyl ester, acrylic acid dimer, benzyl (meth) acrylate, 1- or 2-naphthyl (meth) acrylate, butoxyethyl (meth) acrylate, cetyl (meth) acrylate Wax esters, cresol (meth) acrylates modified with ethylene oxide (hereinafter referred to as "EO"), dipropylene glycol (meth) acrylates, ethoxylated phenyl (meth) acrylates, ( Isooctyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) propyl Isobutyl Esters, dicyclopentyl (meth) acrylate, dicyclopentyloxyethyl (meth) acrylate, (meth) acrylic myristate, lauryl (meth) acrylate, methoxydipropylene glycol ( (Meth) acrylate, methoxytripropylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, neopentyl glycol Benzoate (meth) acrylate, nonylphenoxy polyethylene glycol (meth) acrylate, nonylphenoxy polypropylene glycol (meth) acrylate, octyl (meth) acrylate, para Cumene phenoxyethylene glycol (meth) acrylate, phenoxy acrylate modified with epichlorohydrin (hereinafter referred to as "ECH"), phenoxyethyl (meth) acrylate, benzene Oxydiethylene glycol (meth) acrylate, phenoxyhexaethylene glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, polyethylene glycol (meth) acrylate Ester, polyethylene glycol-polypropylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, octadecyl (meth) acrylate, EO-modified succinic acid (meth) acrylate, ( Methacrylate Bromophenyl, EO-modified tribromophenyl (meth) acrylate, dodecyl (meth) acrylate, tri-dodecyl (meth) acrylate, p-isopropenylphenol, N-ethylene Pyrrolidone, N-vinylcaprolactam.

Among the monofunctional polymerizable monomers containing an ethylenically unsaturated bond, a monofunctional (meth) acrylate compound is preferably used in the present invention from the viewpoint of photocurability. Examples of the monofunctional (meth) acrylate compound include monofunctional (meth) acrylate compounds exemplified in the monofunctional polymerizable monomer containing an ethylenically unsaturated bond.

Furthermore, among monofunctional (meth) acrylate compounds, a monofunctional (meth) acrylate having an aromatic structure and / or an alicyclic hydrocarbon structure is preferred from the viewpoint of dry etching resistance, more preferably A monofunctional (meth) acrylate having an aromatic structure.

Among such monofunctional (meth) acrylates having an aromatic structure and / or an alicyclic hydrocarbon structure, benzyl (meth) acrylate and 2-phenoxyethyl (meth) acrylate are preferred. Ester, benzyl (meth) acrylate having a substituent on the aromatic ring (preferable substituents are alkyl having 1 to 6 carbons, alkoxy having 1 to 6 carbons, cyano), (methyl ) 1- or 2-naphthyl acrylate, 1- or 2-naphthyl methyl (meth) acrylate, 1- or 2-naphthyl ethyl (meth) acrylate, bicyclo (meth) acrylate Amyl ester, dicyclopentyloxyethyl (meth) acrylate, iso (meth) acrylate Ester, adamantane (meth) acrylate, more preferably benzyl (meth) acrylate, benzyl (meth) acrylate having a substituent on the aromatic ring, monofunctional (meth) acrylate having a naphthalene structure The compound is particularly preferably 1- or 2-naphthyl (meth) acrylate and 1- or 2-naphthyl methyl (meth) acrylate.

In the present invention, as the polymerizable monomer, it is also preferable to use a polyfunctional polymerizable unsaturated monomer having two or more ethylenically unsaturated bond-containing groups.

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, dihydroxy Methyldicyclopentane di (meth) acrylate, di (meth) acrylated isotricyanate, 1,3-butanediol 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, allyl Oxypolyethylene glycol acrylate, 1,9-nonanediol di (meth) acrylate, EO modified bisphenol A di (meth) acrylate, PO modified bisphenol A bis ( (Meth) acrylates, modified bisphenol A di (meth) acrylate, EO modified bisphenol F di (meth) acrylate, ECH modified hexahydrophthalic acid diacrylate Hydroxytrimethylacetic 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, modified with caprolactone Hydroxytrimethylacetate 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) acrylic acid Ester, polypropylene glycol di (meth) acrylate, ECH-modified propylene glycol di (meth) acrylate, siloxane di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethyl Diethylene glycol di (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, neomethylol modified trimethylolpropane di (meth) acrylate, tripropylene glycol di (Meth) acrylate, EO-modified tripropylene glycol di (meth) acrylate, triglycerol di (meth) acrylate, dipropylene glycol di (meth) acrylate, divinylethylene urea, diethylene glycol Vinylpropion urea, o-, m-, p-xylylene di (meth) acrylate, 1,3-adamantane diacrylate, Alkanedimethanol diacrylate, m-xylylene di (meth) acrylate.

Among these, neopentyl glycol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, and tripropylene glycol di (meth) propylene Acid ester, tetraethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, o-, m-, Bifunctional (meth) acrylates such as p-benzenedi (meth) acrylate, o-, m-, p-benzenedimethyldi (meth) acrylate and the like are particularly suitable for use in the present invention.

The polymerizable compound used in the curable composition of the present invention is preferably a (meth) acrylate compound, and particularly from the viewpoint of etching resistance, the polymerizable compound having an alicyclic hydrocarbon group and / or an aromatic group ( The (meth) acrylate compound is particularly preferably a (meth) acrylate compound having an aromatic group.

The (meth) acrylate compound is preferably a compound having two (meth) acrylate groups, more preferably a compound having one (meth) acrylate group and two (meth) groups. Acrylate-based compounds.

The molecular weight of the compound having two (meth) acrylate groups is preferably 100 to 500, and more preferably 170 to 300. The compound having two (meth) acrylate groups is preferably represented by, for example, the formula "A ¹ -LA ² ". Here, A ¹ and A ² in the formula each independently represent a (meth) acrylate group, and L represents a divalent linking group. The divalent linking group is preferably an alkylene group, an alkylene group, or a combination thereof. The carbon number of the divalent linking group is preferably from 2 to 20, more preferably from 4 to 12, and even more preferably from 5 to 10.

The molecular weight of the compound having one (meth) acrylate is preferably 100 to 500, more preferably 170 to 400, and even more preferably 200 to 300. The compound having one (meth) acrylate group is preferably represented by the formula "A ¹ -LH", for example. Here, A ¹ and L in the formula are synonymous with A ¹ and L in the formula “A ¹ -LA ² ” of the compound having two (meth) acrylate groups, and preferred ranges are also the same. H is a hydrogen atom.

The curable composition of the present invention may contain a polymerizable compound having a silicon atom and / or a fluorine atom. Examples of the polymerizable compound having a fluorine atom include a polymerizable compound having a fluorine-containing alkyl group having 1 to 9 carbon atoms. Examples of the polymerizable group include a (meth) acrylate group. As the polymerizable compound having a fluorine atom, for example, reference may be made to the descriptions in paragraphs 0022 to 0223 of International Publication No. 2010/137724, and the content thereof is incorporated into the specification of the present application.

On the other hand, in the present invention, it is preferable that the polymerizable compound having a silicon atom and / or a fluorine atom is not substantially contained. In the present invention, since the fluorine-containing compound represented by the general formula (I) is blended, even if the polymerizable compound having a silicon atom and / or a fluorine atom is not substantially contained, the inkjet discharge accuracy and Releasability and their stability over time have been improved. The term “substantially free” means, for example, that the total amount of the fluorine-containing compound represented by the general formula (I) is 1% by mass or less.

Among the components of all polymerizable compounds contained in the curable composition of the present invention, the total of the polymerizable compounds having one (meth) acrylate group is preferably 60% by mass relative to the total polymerizable compounds. Hereinafter, it is more preferably 45% by mass or less, and even more preferably 35% by mass or less. The lower limit value is preferably 5 mass% or more, and more preferably 10 mass% or more. By blending a polymerizable compound having one (meth) acrylate group, the pattern forming property can be further improved. The total of the polymerizable compounds having two (meth) acrylate groups is preferably more than all the polymerizable compounds. 40 to 100% by mass, more preferably 55 to 95% by mass, and even more preferably 65 to 90% by mass.

Among the components of all polymerizable compounds contained in the curable composition of the present invention, the total of the polymerizable compounds having an alicyclic hydrocarbon group and / or an aromatic group is preferably 30 to 100% by mass of the total polymerizable compounds. , More preferably 50 to 100% by mass, and even more preferably 60 to 100% by mass.

The (meth) acrylate polymerizable compound containing an aromatic group as the polymerizable compound is preferably 30 to 100% by mass of the total polymerizable components, more preferably 50 to 100% by mass, and particularly preferably 60 to 100% by mass. .

A particularly preferred embodiment is that the amount of the following polymerizable compound (A1) is 0 to 60% by mass of all polymerizable components, more preferably 5 to 45% by mass, and even more preferably 10 to 40% by mass. The following polymerization The amount of the sexual compound (A2) is 40 to 100% by mass of all polymerizable components, more preferably 55 to 95% by mass, and even more preferably 60 to 90% by mass.

(A1) A polymerizable compound having a linear or branched alkyl group having 10 to 20 carbon atoms and a (meth) acrylate group, or a linear or branched group having 1 to 12 carbon atoms Polymerizable compound of alkyl-substituted aromatic group and (meth) acrylate group

(A2) A polymerizable compound having an aromatic group (preferably phenyl, naphthyl, and phenylene, more preferably phenylene) and two (meth) acrylate groups

The polymerizable compound may be used singly or in combination of two or more kinds.

In the pattern inversion method described later, it is preferable to have no etching resistance.

<Photopolymerization initiator (B)>

The curable composition of the present invention contains a photopolymerization initiator. The photopolymerization initiator used in the present invention can be used as long as it is a compound that generates an active species that polymerizes the polymerizable compound by light irradiation. The photopolymerization initiator is preferably a radical polymerization initiator or a cationic polymerization initiator, and more preferably a radical polymerization initiator. In the present invention, a plurality of photopolymerization initiators may be used in combination.

As the radical photopolymerization initiator used in the present invention, for example, a commercially available initiator can be used. As such examples, for example, those described in paragraph number 0091 of Japanese Patent Application Laid-Open No. 2008-105414 can be preferably used. Among them, acetophenone-based compounds, fluorenylphosphine oxide-based compounds, and oxime ester-based compounds are particularly preferred from the viewpoint of curing sensitivity and absorption characteristics.

The photopolymerization initiator may be used alone or in combination of two or more. When two or more kinds are used in combination, it is more preferable to use two or more kinds of radical polymerization initiators in combination. Specific examples include Darocure (registered trademark) 1173 and Irgacure (registered trademark) 907, Darocure 1173 and Lucirin (registered trademark) TPO, Darocure 1173 and Irgacure (registered trademark) 819, Darocure 1173 and Irgacure (registered trademark) OXE01, Irgacure Combination of 907 and Lucirin TPO, Irgacure 907 and Irgacure 819. By making such a combination, it is possible to further expand the exposure margin.

The preferred ratio (mass ratio) when combined with a photopolymerization initiator is preferably 9: 1 to 1: 9, more preferably 8: 2 to 2: 8, and even more preferably 7: 3 to 3: 7.

The content of the photopolymerization initiator used in the present invention is in all the components other than the solvent, that is, in the entire solid content of the curable composition of the present invention. For example, it is preferably 0.01 to 15% by mass, and more preferably 0.1 to 10 mass%, particularly preferably 0.5 to 7 mass%. When two or more photopolymerization initiators are used, the total amount thereof falls within the above range. If the content of the photopolymerization initiator is 0.01% by mass or more, the sensitivity (rapid curing), resolution, line edge roughness, and coating film strength tend to be further improved, which is preferable. In addition, if the content of the photopolymerization initiator is 15% by mass or less, the light transmittance, coloring properties, and handling properties tend to be further improved, which is preferable.

<Fluorine compound (C)>

The curable composition of the present invention contains a fluorine-containing compound (C) represented by the following general formula (I). By using such a fluorine-containing compound (C), the mold release property, inkjet discharge accuracy, and time-dependent stability of the curable composition of the present invention can be improved.

In the general formula (I), Rf ¹ represents a fluorine-containing alkyl group having 1 to 6 carbon atoms having 2 or more fluorine atoms; R ¹ represents an alkyl group having 1 to 7 carbon atoms or an aryl group having 6 to 8 carbon atoms; m represents an integer from 0 to 2, and n represents an integer from 1 to 3. When n represents 2 or 3, Rf ¹ may be different from each other.

In the general formula (I), Rf ¹ represents a fluorine-containing alkyl group having 1 to 6 carbon atoms having two or more fluorine atoms. Rf ¹ represents any of linear, branched, and cyclic, but is preferably linear or branched, and more preferably linear.

The carbon number of Rf ¹ is more preferably 3 to 6, particularly preferably 4 to 6, and particularly preferably 5 or 6.

The structure of the terminal of Rf ¹ is preferably -CF ₃ or -C (HF ₂ ), and particularly preferably -CF ₃ .

The substitution rate of the fluorine atom of Rf ¹ is preferably 80 to 100%, more preferably 90 to 100%, and even more preferably 100% (perfluoroalkyl). For example, Rf ^{1 is} preferably a perfluoroalkyl group having 4 to 6 carbon atoms. The substitution rate of fluorine atoms refers to the ratio (%) of hydrogen atoms to fluorine atoms in alkyl groups having 1 to 6 carbon atoms.

Specific examples of Rf ¹ include -CF ₃ , CF ₃ CF _2- , CF ₃ (CF ₂ ) _2- , CF ₃ (CF ₂ ) _3- , CF ₃ (CF ₂ ) _4- , CF ₃ ( CF ₂ ) _5- , (CF ₃ ) ₂ CH-, (CF ₃ ) ₂ C (CH ₃ )-, (CF ₃ ) ₂ CF (CF ₂ ) _2- , (CF ₃ ) ₂ CF (CF ₂ ) ₄ -, H (CF ₂ ) _2- , H (CF ₂ ) _4- , H (CF ₂ ) ₆ -and so on. Among these, CF ₃ (CF ₂ ) _4- , CF ₃ (CF ₂ ) _5- , and H (CF ₂ ) ₆ -are more preferred, and CF ₃ (CF ₂ ) ₅ -is particularly preferred.

In the general formula (I), R ¹ represents an alkyl group having 1 to 7 carbon atoms or an aryl group having 6 to 8 carbon atoms, preferably an alkyl group having 1 to 7 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. base. R ¹ may be any of linear, branched, and cyclic, but is preferably linear or branched, and more preferably linear.

The number of carbon atoms of the aryl group having 6 to 18 carbon atoms is preferably 6 to 8, and more preferably 6.

Specific examples of R ¹ include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, third butyl, n-pentyl, isopentyl, neopentyl, and hexyl. , Heptyl, cyclopentyl, cyclohexyl, phenyl, tolyl, benzyl and the like. Among these, a methyl group, an ethyl group, an n-propyl group, and an isopropyl group are more preferable, a methyl group or an ethyl group is more preferable, and an ethyl group is particularly preferable.

In the general formula (I), m represents an integer of 0 to 2, preferably 1 or 2, and more preferably 1.

n represents an integer of 1 to 3, preferably 1 or 2, and more preferably 1.

As preferable specific examples of the fluorine-containing compound (C), the following compounds C-1 to C-15 can be mentioned, but the fluorine-containing compound (C) used in the present invention is not limited to these compounds.

The molecular weight of the fluorine-containing compound (C) is preferably 140 to 550, more preferably 200 to 500, and even more preferably 400 to 450.

The content of the fluorinated compound (C) in the curable composition of the present invention is preferably 1 to 10% by mass, more preferably 1 to 5% by mass, and even more preferably 1 to 5% by mass of all components other than the solvent. 3% by mass. When the content of the fluorine-containing compound (C) is 1% by mass or more, the releasability is further increased. When the content of the fluorine-containing compound (C) is 10% by mass or less, the pattern roughness is further optimized. The fluorine-containing compound (C) may be used alone or in combination of two or more. When two or more kinds of fluorine-containing compounds (C) are used, the total amount thereof falls within the above range.

<Non-polymerizable compound (D) having a polyalkanediol structure>

The curable composition of the present invention is preferred in order to improve the mold release property. It is a non-polymerizable compound (D) containing a polyalkanediol structure. Here, a non-polymerizable compound means a compound which does not have a polymerizable group.

The polyalkylene structure is preferably a polyethylene glycol structure, a polypropylene glycol structure, a polybutylene glycol structure, or a mixed structure thereof, and more preferably a polyethylene glycol structure or a polypropylene glycol structure. Further, a branched structure using a polyglycol such as glycerin or pentaerythritol as a core is also preferable.

The polyalkylene glycol structure preferably has 3 to 30 alkanediol constituent units, more preferably 5 to 20, particularly preferably 7 to 15 and particularly preferably 9 to 13.

At least one hydroxyl group at the terminal of the polyalkylene glycol structure may be substituted with an organic group, or all the hydroxyl groups may be unsubstituted. The substituted organic group is preferably an organic group having 1 to 20 carbon atoms, and more preferably has an oxygen atom, a fluorine atom, or a silicon atom. The substituted organic group is connected to the polyalkylene glycol structure by an ether bond, an ester bond, or a divalent linking group. Specific examples of the substituted organic group are a hydrocarbon group such as methyl, ethyl, butyl, allyl, benzyl, phenyl, a fluoroalkyl group, a fluoroalkyl ether group, and a polysiloxane group.

The number-average molecular weight of the non-polymerizable compound (D) is preferably 300 to 3000, more preferably 400 to 2000, and even more preferably 500 to 1500.

Specific examples of the preferred non-polymerizable compound (D) include polyethylene glycol, polypropylene glycol, polyethylene glycol glyceryl ether, polypropylene glycol glyceryl ether, and the like, methyl etherate, and acetamidate. A fluorine-containing compound represented by the following general formula (II).

Formula (II)

In the general formula (II), Rf ² and Rf ³ each independently represent a fluorine-containing alkyl group having 1 to 6 carbon atoms having 2 or more fluorine atoms; p ¹ and p ² each independently represent an integer of 1 to 3, q ¹ and q ² each independently represent an integer of 0 to 2, r represents an integer of 2 to 4, and s represents 6 to 20.

The preferred ranges of Rf ² and Rf ³ in the general formula (II) are synonymous with the preferred ranges of Rf ¹ in the general formula (I), and the preferred ranges or specific examples of Rf ² and Rf ³ are also the same.

In the general formula (II), p ¹ and p ² each independently represent an integer of 1 to 3, preferably 1 or 2, and more preferably 1.

q ¹ and q ² each independently represent an integer of 0 to 2, preferably 1 or 2, and more preferably 1.

r represents an integer of 2 to 4, preferably 2 or 3, and more preferably 2.

s represents 6-20, preferably 7-15, and more preferably 9-13.

Regarding the non-polymerizable compound (D), reference can be made to the descriptions in paragraphs 0105 to 0106 of Japanese Patent Application Laid-Open No. 2013-036027, the contents of which are incorporated into the description of this case.

The content of the non-polymerizable compound (D) is preferably 1 to 10% by mass, more preferably 2 to 8% by mass, even more preferably 3 to 7% by mass, and even more preferably 4 to 6% by mass in all compositions except the solvent. %.

In the curable composition of the present invention, the quality of the fluorine-containing compound represented by the general formula (I) and the non-polymerizable compound having a polyalkylene glycol structure is preferably 1: 5 to 5: 5, more preferably It is preferably 1: 5 ~ 2: 5. By setting it as such a range, the effect of the invention can be achieved more effectively.

<Polymerization inhibitor>

The curable composition of the present invention preferably contains a polymerization inhibitor. The content of the polymerization inhibitor is 0.001 to 0.1% by mass, preferably 0.005 to 0.08% by mass, and more preferably 0.01 to 0.05% by mass with respect to the total polymerizable monomer. The viscosity change over time is suppressed while maintaining a high degree of hardening sensitivity. The polymerization inhibitor may be added during the production of the polymerizable monomer, or may be added to the hardened composition of the present invention at a later time. Specific examples of the polymerization inhibitor include 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxy radical. Moreover, as a specific example of another polymerization inhibitor, the thing described in the paragraph number 0121 of Unexamined-Japanese-Patent No. 2012-169462 is mentioned, The content is integrated in the specification of this case.

<Surfactant>

The curable composition of the present invention may contain a surfactant as needed. In general, a so-called surfactant is a substance that has a hydrophobic portion and a hydrophilic portion in the molecule, and changes the properties of the interface significantly with a small amount of addition. The surfactant in the present invention is a substance having a hydrophobic part and a hydrophilic part in the molecule, and a small amount of addition to significantly reduce the surface tension of the hardenable composition. For example, it is added at 1% by mass or less with respect to the hardenable composition. A substance that reduces the surface tension of the curable composition from 40 mN / m to 30 mN / m or less. When a surfactant is contained in the curable composition of the present invention, the effect of improving the uniformity of coating or the effect of improving the mold release property can be expected.

As the surfactant used in the present invention, a nonionic surfactant is preferred, and a fluorine-based surfactant and a Si-based surfactant are more preferred. At least one of a surfactant and a fluorine-Si surfactant, and a fluorine-based nonionic surfactant is particularly preferred. Here, the so-called "fluorine-Si surfactant" refers to a person who has both the fluorine-based surfactant and the Si-based surfactant.

Examples of the fluorine-based nonionic surfactant that can be used in the present invention include trade names Fluorad (Sumitomo 3M), Megafac (DIC), Surflon (AGC Seimi Chemical), Unidyne (DAIKIN Industries), Ftergent (NEOS), Eftop (Mitsubishi Materials Electronics), Polyflow (Kyoeisha Chemical), KP (Shin-Etsu Chemical Industry), Troyzol (TROY Chemical), PolyFox (OMNOVA), Capstone (DuPont), etc.

The content of the surfactant used in the present invention is in the entire composition, for example, it is preferably 0.01 to 5% by mass, more preferably 0.1 to 4% by mass, and even more preferably 1 to 3% by mass. The surfactant may be used alone or in combination of two or more. When two or more surfactants are used, the total amount is within the above range. If the surfactant is in the range of 0.01 to 5% by mass in the curable composition of the present invention, the effect of uniformity of coating is good, and it is difficult to cause deterioration of mold transfer characteristics due to excessive surfactant.

In the present invention, by blending the fluorine-containing compound represented by the general formula (I), a low mold release force can be achieved even when the surfactant is substantially free of the surfactant. The term “substantially free” means, for example, that the total amount of the fluorine-containing compound represented by the general formula (I) is 1% by mass or less.

<Other ingredients>

The curable composition of the present invention contains, in addition to the above-mentioned components, a photosensitizer, an antioxidant, an ultraviolet absorber, and a light stabilizer, if necessary. Agents, anti-aging agents, plasticizers, adhesion promoters, thermal polymerization initiators, photobase generators, colorants, inorganic particles, elastomer particles, basic compounds, photoacid generators, photoacid promoters, chains Transfer agent, antistatic agent, flow regulator, defoamer, dispersant, etc. Specific examples of such components include those described in paragraph numbers 092 to 0093 and paragraph numbers 0113 to 0137 of Japanese Patent Application Laid-Open No. 2008-105414, which are incorporated into the specification of this case.

In the present invention, by blending a fluorine-containing compound represented by the general formula (I), even if it becomes substantially free of a fluorine-containing surfactant, a fluorine-containing silane coupling agent, a fluorine-containing monomer molecule, or Non-Patent Document 4 The described form of the non-reactive fluorinated compound can also achieve a low release force. Further, in the present invention, the non-reactive fluorine-containing compound described in Non-Patent Document 4 is substantially not included, the stability of the hardening composition over time is improved, and deterioration in inkjet discharge accuracy can be suppressed. . The term "substantially free" means, for example, 1% by mass or less of the blending amount of the fluorine-containing compound represented by the general formula (I).

<Solvent>

The curable composition of the present invention may contain a solvent. The content of the solvent in the curable composition of the present invention is preferably 5% by mass or less, more preferably 3% by mass or less, and particularly preferably does not substantially contain a solvent. Here, the term "substantially free of a solvent" means, for example, that the total mass in the curable composition of the present invention is 1% by mass or less. When the curable composition of the present invention is coated on a substrate by an inkjet method, if the blending amount of the solvent is small, it is preferable because the viscosity change of the composition due to volatilization of the solvent can be suppressed.

As described above, the curable composition of the present invention does not necessarily include a solvent, but may be added arbitrarily when the viscosity of the composition is finely adjusted and the like. As the kind of solvent that can be preferably used in the curable composition of the present invention, as long as it is a solvent generally used for the photocurable curable composition or photoresist, the compound used in the present invention can be dissolved and uniformly dispersed. Yes, and there is no particular limitation as long as it does not respond to these ingredients. Examples of the solvent that can be used in the present invention include those described in Paragraph No. 0088 of Japanese Patent Application Laid-Open No. 2008-105414, the contents of which are incorporated in the description of this case.

The curable composition system of this invention can be adjusted by mixing each said component. The mixing and dissolution of the curable composition of the present invention is usually performed in a range of 0 ° C to 100 ° C. Moreover, after mixing each said component, it is preferable to filter with the filter which has a pore diameter of 0.003 micrometer-1.0 micrometer, for example. The filtration system can be carried out in multiple stages or repeated many times. In addition, the filtered liquid may be re-filtered. The material of the filter used for filtration can be polyethylene resin, polypropylene resin, fluororesin, nylon resin, etc., but it is not particularly limited.

The viscosity of the hardenable composition of the present invention at 23 ° C is preferably 15 mPa. Below s, more preferably 12mPa. Below s, especially preferred is 11mPa. Below s, especially good is 10mPa. s or less. By setting it as such a range, the inkjet discharge precision and pattern formation property can be improved. In the curable composition of the present invention, in order to reduce the viscosity of the solvent while reducing the blending amount of the solvent, the polymerizable compound (A) is preferably blended to act as a reactive diluent. Examples of the polymerizable compound that functions as a reaction diluent include a polymerizable compound having one (meth) acrylate group. Thing.

The surface tension of the hardenable composition of the present invention is preferably 25 to 35 mN / m, more preferably 27 to 34 mN / m, particularly preferably 28 to 32 mN / m, and particularly preferably 29 to 31 mN / m. By setting it as such a range, the inkjet discharge precision and surface smoothness can be improved. In particular, the curable composition of the present invention preferably has a viscosity of 15 mPa at 23 ° C. Below s and the surface tension is 25 ~ 35mN / m, more preferably the viscosity is 11mPa. Below s, the surface tension is 28 ~ 32mN / m, especially the viscosity is 10mPa. s or less and surface tension of 29 to 31 mN / m.

<Pattern formation method>

Hereinafter, a pattern forming method (pattern transfer method) using the curable composition of the present invention will be specifically described. In the pattern forming method of the present invention, the curable composition of the present invention is first coated on a substrate or a mold having a pattern, and the curing composition of the present invention is sandwiched between the mold and the substrate. Light exposure.

As a method for applying the curable composition of the present invention to a substrate, generally known coating methods can be used, and for example, a dip coating method, an air knife coating method, a curtain coating method, a wire rod coating method, and a gravure coating can be used. Method, a squeeze coating method, a spin coating method, a slit scanning method, or an inkjet method, etc., a coating film or a droplet is arranged on a substrate. In particular, since the curable composition of the present invention contains the fluorine-containing compound (C) represented by the general formula (I), even when an inkjet method is used, the inkjet dischargeability can be improved.

When the curable composition of the present invention is sandwiched between a mold and a substrate, helium gas may be introduced between the mold and the substrate. By using such a method, it is possible to promote the gas to penetrate the quartz mold and promote the disappearance of residual air bubbles. . In addition, by reducing the dissolved oxygen in the curable composition, it is possible to suppress the barrier of radical polymerization during exposure. Instead of helium, a condensable gas may be introduced between the mold and the substrate. By using such a method, the introduced condensable gas system is condensed to reduce the volume, and the elimination of residual air bubbles can be further promoted. The so-called condensable gas refers to a gas that condenses due to temperature or pressure. For example, trichlorofluoromethane, 1,1,1,3,3-pentafluoropropane and the like can be used. Regarding the condensable gas, for example, reference can be made to the description in paragraph 0023 of Japanese Patent Application Laid-Open No. 2004-103817 and paragraph 0003 of Japanese Patent Application Laid-Open No. 2013-254783, which are incorporated into the specification of this case.

During exposure, the exposure illuminance should be in the range of 1 mW / cm ² to 200 mW / cm ² . When it is 1 mW / cm ² or more, the productivity can be improved because the exposure time can be shortened. When it is 200 mW / cm ² or less, the deterioration of the characteristics of the cured film due to the occurrence of side reactions is preferably suppressed. Preferably in the range of exposure amount ^{5mJ / cm 2 ~ 1000mJ / cm} 2 of. If it is less than 5 mJ / cm ² , the exposure margin becomes narrow, the photo-hardening becomes insufficient, and problems such as adhesion of unreacted substances to the mold tend to occur. On the other hand, if it exceeds 1000 mJ / cm ² , the cured film may be deteriorated due to the decomposition of the composition.

In addition, in order to suppress the radical polymerization obstruction caused by oxygen during exposure, inert gases such as nitrogen, helium, argon, and carbon dioxide may be flowed, and the oxygen concentration in the atmosphere is preferably controlled to 10 kPa or less. The oxygen concentration in the atmosphere is more preferably 3 kPa or less, and even more preferably 1 kPa or less.

In the pattern forming method of the present invention, after the pattern forming layer (the layer formed of the curable composition of the present invention) is cured by light irradiation, if necessary, the cured pattern may be further heated by heating it. Steps of hardening. The heat for curing the curable composition of the present invention after light irradiation is preferably 150 to 280 ° C, and more preferably 200 to 250 ° C. The time for applying heat is preferably 5 to 60 minutes, and more preferably 15 to 45 minutes.

As a specific example of the pattern forming method, those described in paragraph numbers 0125 to 0136 of Japanese Patent Application Laid-Open No. 2012-169462 can be cited, and the contents thereof are incorporated into the specification of this case.

The pattern forming method of the present invention is applicable to a pattern inversion method. Specifically, a photoresist pattern is formed on a substrate to be processed having a carbon film (SOC) by the pattern forming method of the present invention. Next, after the photoresist pattern is covered with a Si-containing film (SOG), the upper portion of the Si-containing film is etched back to expose the photoresist pattern, and the exposed photoresist pattern is removed by an oxygen plasma or the like to form Si-containing Inverted pattern of the film. Furthermore, the reverse pattern containing the Si film is used as an etching mask, and the carbon film on the lower layer is etched to transfer the reverse pattern to the carbon film. Finally, the carbon film to which the above-mentioned reverse pattern is transferred is used as an etching mask to etch the substrate. As examples of such a method, refer to paragraphs 0016 to 0030 of Japanese Patent Application Laid-Open No. 5-267253, Japanese Patent Application Laid-Open No. 2002-110510, and Japanese Patent Application Laid-Open No. 2006-521702, the contents of which are incorporated into the description of this case.

In addition, the pattern forming method of the present invention may include: a step of coating an underlayer film composition on a substrate to form an underlayer film; a step of coating the curable composition of the present invention on a surface of the underlayer film; A step of curing the curable composition of the present invention by light irradiation in a state where the curable composition of the present invention and an underlayer film are sandwiched between molds; and a step of peeling the mold. Furthermore, after the underlayer film composition is coated on the substrate, the underlayer film composition may be irradiated by heat or light. After being partially cured, the curable composition of the present invention is applied.

The lower-layer film composition contains, for example, a curable main agent. The curable main agent system may be thermosetting or photocuring, and is preferably thermosetting. The molecular weight of the curable main agent is preferably 400 or more, and may be a low-molecular compound or a polymer, and is preferably a polymer. The molecular weight of the curable main agent is preferably 500 or more, more preferably 1,000 or more, and even more preferably 3,000 or more. The upper limit of the molecular weight is preferably 200,000 or less, more preferably 100,000 or less, and even more preferably 50,000 or less. When the molecular weight is 400 or more, the volatilization of the components can be more effectively suppressed. For example, there may be mentioned those described in Japanese Patent Application Publication No. 2009-503139 in paragraph numbers 0040 to 0056, and the contents thereof are incorporated into the specification of this case.

The content of the curable main agent is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more in all components other than the solvent. The curable main agent may be two or more types. In this case, the total amount is preferably in the above range.

The underlayer film composition preferably contains a solvent. The preferred solvent is a solvent having a boiling point of 80 to 200 ° C under normal pressure. The type of the solvent may be any solvent that can dissolve the underlayer film composition, and a solvent having any one or more of an ester structure, a ketone structure, a hydroxyl group, and an ether structure is preferred. Specifically, the preferred solvent is a single or mixed solvent selected from propylene glycol monomethyl ether acetate, cyclohexanone, 2-heptanone, γ-butyrolactone, propylene glycol monomethyl ether, and ethyl lactate. From the viewpoint of coating uniformity, a solvent containing propylene glycol monomethyl ether acetate is most preferable.

The content of the above-mentioned solvent in the underlayer film composition is optimally adjusted according to the viscosity, coatability, and intended film thickness of components other than the solvent. It can be added in the range of 70% by mass or more in the entire composition from the viewpoint of improving the coating property, preferably 90% by mass or more, more preferably 95% by mass or more, and even more preferably 99% by mass or more.

The lower film composition system may contain at least one of a surfactant, a thermal polymerization initiator, a polymerization inhibitor, and a catalyst as other components. These blending amounts are preferably 50% by mass or less with respect to all components other than the solvent.

The underlayer film composition can be adjusted by mixing the above components. Moreover, after mixing each said component, it is preferable to filter with the filter which has a pore diameter of 0.003 micrometer-1.0 micrometer, for example. The filtration system can be carried out in multiple stages or repeated many times. In addition, the filtered liquid may be re-filtered. The material of the filter used for filtration can be polyethylene resin, polypropylene resin, fluororesin, nylon resin, etc., but it is not particularly limited.

The underlayer film composition is applied on a substrate to form an underlayer film. As a method for coating on a substrate, for example, a dip coating method, an air knife coating method, a curtain coating method, a wire rod coating method, a gravure coating method, a squeeze coating method, a spin coating method, and a slit scanning method can be used. Method, inkjet method, etc., a coating film or a droplet is arranged on a substrate. From the viewpoint of film thickness uniformity, a spin coating method is more preferred. Then, the solvent was dried. The preferred drying temperature is 70 ° C to 130 ° C. The hardening is more preferably performed by active energy (preferably heat and / or light). It is preferable to heat-harden at a temperature of 150 ° C to 250 ° C. The step of drying the solvent and the step of hardening may be performed simultaneously. As described above, it is preferable to apply a curable composition of the present invention after coating a part of the underlayer film composition by applying heat or light to harden a part of the underlayer film composition. If such a method is adopted, the hardenability of the present invention When the composition is photo-cured, the underlying film composition is also completely cured, and the adhesiveness tends to further increase.

The film thickness of the underlayer film formed from the curable composition of the present invention varies depending on the intended use, but is about 0.1 nm to 100 nm, preferably 1 to 20 nm, and more preferably 2 to 10 nm. The underlayer film composition can also be applied by multiple application. The resulting lower layer film is preferably as flat as possible.

The substrate (substrate or support) can be selected according to various applications, such as quartz, glass, optical film, ceramic material, vapor-deposited film, magnetic film, reflective film, metal substrates such as Ni, Cu, Cr, Fe, etc. Polymer substrates such as paper, SOG (Spin On Glass), polyester film, polycarbonate film, polyimide film, TFT array substrate, electrode plate for PDP, glass or transparent plastic substrate, ITO or metal There are no particular restrictions on conductive substrates, insulating substrates, semiconductor substrates such as silicon, silicon nitride, polycrystalline silicon, silicon oxide, and amorphous silicon. However, when used for etching, as described later, it is preferable to use a semiconductor as a substrate.

<Pattern>

As described above, the pattern formed by the pattern forming method of the present invention can be used as a permanent film (a photoresist for a structural member) or an etching resist used in a liquid crystal display (LCD) or the like.

Moreover, the solvent resistance of the pattern using the curable composition of this invention is also favorable. The curable composition in the present invention is preferably highly resistant to a variety of solvents. Particularly preferred is a solvent used in a general substrate manufacturing process, such as immersion in an N-methylpyrrolidone solvent at 25 ° C for 10 No change in film thickness occurs in minutes.

The pattern formed by the pattern forming method of the present invention is also suitable as an etching photoresist. When the curable composition of the present invention is used as an etching photoresist, first, for example, a silicon wafer having a thin film of SiO ₂ or the like is used as a base material, and a nanometer-level photoresist is formed on the base material by the pattern forming method of the present invention. Fine pattern. Then, in the case of wet etching, hydrogen fluoride or the like is used, and in the case of dry etching, etching is performed using an etching gas such as CF ₄ to form a desired pattern on the substrate. The hardenable composition of the present invention is also excellent in etching resistance against dry etching using carbon fluoride or the like.

<Method for Manufacturing Semiconductor Device>

The method for manufacturing a semiconductor device according to the present invention is characterized by using the above pattern as an etching mask. Using the above pattern as an etching mask, the substrate is treated. For example, a pattern is used as an etching mask, and dry etching is performed to selectively remove the upper layer portion of the substrate. By repeating such a process on the substrate, a semiconductor device can be obtained. The semiconductor device is, for example, an LSI (Large Scale Integrated Circuit).

[Example]

Examples are given below to explain the present invention more specifically. The materials, usage amounts, proportions, processing contents, processing procedures, and the like shown in the following examples can be appropriately changed as long as they do not depart from the spirit of the present invention. Therefore, the scope of the present invention is not limited by the specific examples shown below. In addition, unless otherwise specified in advance, "%" is the quality benchmark.

<Synthesis of fluorine-containing compound (C)>

The fluorine-containing compounds (C-10) to (C-13) were synthesized by the methods described below.

Synthesis of fluorinated compound (C-10)

18.2 g of 3,3,4,4,5,5,5,6,7,7,8,8,8,8-tridecylfluorooctanol (manufactured by Wako Pure Chemical Industries) and 10.2 g of acetic anhydride (and (Made by Koko Pure Chemical Industries) and 50 mL of ethyl acetate were stirred and mixed under an ice bath, and 10.1 g of triethylamine (made by Wako Pure Chemical Industries) was dropped while maintaining an internal temperature of 10 ° C or lower. After the completion of the dropping, a reaction was performed at 25 ° C. for 6 hours, and then 150 mL of ethyl acetate and 100 mL of 2% sodium bicarbonate water were added and stirred for 10 minutes. Then, the organic layer obtained by the liquid separation was washed with 100 mL of 0.1N hydrochloric acid water, and then washed with 100 mL of pure water, and then concentrated under reduced pressure to obtain 19.1 g (yield: 94%) of the intended fluorine-containing compound (94%). C-10) is a colorless liquid.

¹ H-NMR (400 MHz, CDCl ₃ , TMS, δ = ppm,): δ = 2.22 (s, 3H), 2.49 (m, 2H), 4.38 (t, 2H).

Synthesis of fluorinated compound (C-11)

Except for using 13.0 g of propionic anhydride (manufactured by Wako Pure Chemical Industries), in the same manner as in the synthesis of the fluorinated compound (C-10), 20.6 g (yield 98%) of the fluorinated compound (C-11) was obtained. It is a colorless liquid.

¹ H-NMR (400 MHz, CDCl ₃ , TMS, δ = ppm,): δ = 1.15 (t, 3H), 2.35 (q, 2H), 2.47 (m, 2H), 4.38 (t, 2H).

Synthesis of fluorinated compound (C-12)

Except that 9.8 g of octyl chloride (manufactured by Wako Pure Chemical Industries) was used, 22.6 g (yield 92%) of the fluorinated compound (C-12) was obtained in the same manner as in the synthesis of the fluorinated compound (C-10). , Is a colorless liquid.

¹ H-NMR (400MHz, CDCl ₃ , TMS, δ = ppm,): δ = 0.88 (t, 3H), 1.29 (m, 6H), 1.63 (m, 2H), 2.32 (t, 2H), 2.47 ( m, 2H), 4.38 (t, 2H).

Synthesis of fluorinated compound (C-13)

Except that 8.4 g of benzamidine chloride (manufactured by Wako Pure Chemical Industries, Ltd.) was used, 22.3 g (yield: 95%) of the fluorine-containing compound (C-13) was obtained in the same manner as in the synthesis of the fluorine-containing compound (C-10). ).

¹ H-NMR (400MHz, CDCl ₃ , TMS, δ = ppm,): δ = 2.61 (m, 2H), 4.63 (t, 2H), 7.45 (t, 2H), 7.58 (t, 1H), 8.04 ( d, 2H).

<Preparation of hardenable composition for photoimprint>

The polymerizable compound (A), the photopolymerization initiator (B), and the fluorine-containing compound (C) were mixed at a mass ratio shown in Table 1 below, and the content was 200 ppm (0.02% by mass) based on the curable composition. In one embodiment, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxy radical (manufactured by Tokyo Chemical Industry Co., Ltd.) is added as a polymerization inhibitor. This was filtered through a 0.1 μm PTFE filter to prepare the hardenable compositions X-1 to X-10 for photoimprinting according to the present invention and the hardenable compositions R-1 to R-4 for comparison. The viscosity and surface tension of the prepared hardening composition at 23 ° C were measured. Using an E-type viscometer RE85L (Toki Sangyo) and a surface tensiometer CBVP-A3 (Kyowa Interface Chemistry), the viscosity and surface tension of the prepared hardening composition at 23 ° C were measured.

The details of the polymerizable compound (A), the photopolymerization initiator (B), the additive (D), and the comparative compound (S) used in the examples and comparative examples are as follows.

<Polymerizable compound (A)>

A-1: 2-phenoxyethyl acrylate (manufactured by Osaka Organic Chemical Industry, Viscoat # 192)

A-2: 4-isobutyl benzyl acrylate (synthesized from 4-isobutyl benzyl alcohol and propylene chloride)

A-3: Dodecyl acrylate (manufactured by Kyoeisha Chemical, Light Acrylate L-A)

A-4: neopentyl glycol diacrylate (manufactured by Kyoeisha Chemical, Light Acrylate NP-A)

A-5: m-xylylene diacrylate (synthesized from α, α'-dichloro-m-xylene and acrylic acid)

<Photopolymerization initiator (B)>

B-1: Irgacure 819 (manufactured by BASF)

B-2: Darocure 1173 (manufactured by BASF)

Non-polymerizable compound (D) having a polyalkanediol structure

D-1: Polypropylene glycol (number average molecular weight 700, manufactured by Wako Pure Chemical Industries)

D-2: A fluorine-containing compound having the following structure (polyethylene glycol dicarboxymethyl ether (number average molecular weight 600, manufactured by Sigma-Aldrich) and 3,3,4,4,5,5,6,6, 6-Ninefluorohexanol (manufactured by Tokyo Chemical Industry Co., Ltd.) is synthesized by dehydration condensation)

Comparative compound (S)

S-1: Methyl Perfluorooctanoate (manufactured by Wako Pure Chemical Industries)

S-2: Acrylic acid 2- (perfluorooctyl) ethyl ester (manufactured by Tokyo Chemical Industry)

<Preparation of lower film composition>

3 g of NK oligo EA-7140 / PGMAc (manufactured by Shin Nakamura Chemical Industry Co., Ltd.) was dissolved in 997 g of propylene glycol monomethyl ether acetate, and then filtered through a 0.1 μm tetrafluoroethylene filter to obtain a lower layer membrane composition. .

NK oligomer EA-7140 / PGMAc (solid content 70%)

Average m + n = 4, average n / (m + n) = 0.5

(Evaluation)

The obtained curable compositions for imprint of each of the examples and comparative examples were evaluated as follows. The results are shown in Table 2 below.

<Inkjet discharge accuracy>

On a silicon wafer, an inkjet printer DMP-2831 (manufactured by FUJIFILM Dimatix) was used to dispense a hardening composition for photoimprint, the temperature of which was adjusted to 23 ° C. with a droplet volume of 1 pl per nozzle, The droplets were applied on a silicon wafer in a square arrangement with 100 μm intervals.

The 2500 points on a 5 mm square of the coated substrate were observed, and the deviation from the square arrangement was measured to calculate the standard deviation σ. The inkjet discharge accuracy is evaluated as A to D as follows.

A: σ <3μm

B: 3μm ≦ σ <5μm

C: 5μm ≦ σ <10μm

D: 10μm ≦ σ

<Release Evaluation>

The lower film composition was spin-coated on a silicon wafer, and heated on a hot plate at 100 ° C. for 1 minute to dry the solvent. Furthermore, the lower-layer film composition was hardened by heating on a hot plate at 220 ° C. for 5 minutes to form an lower-layer film. The film thickness of the lower layer film after curing was 3 nm.

On the surface of the lower film on the silicon wafer, an inkjet printer DMP-2831 (manufactured by FUJIFILM Dimatix) was used, and a droplet amount of 1 pl per nozzle was used to spit out light embossing for which the temperature was adjusted to 23 ° C. The sexual composition is applied on the lower layer film so that the droplets are arranged in a square array with an interval of about 100 μm.

For the hardenable composition that has been applied on the underlayer film, contact it with a quartz mold under a reduced pressure of 0.1 atmospheres (line / gap = 1/1, line width 30nm, groove depth 60nm, line edge roughness 3.0nm), Using a high-pressure mercury lamp from the side of the quartz mold, exposure was performed under the condition of 100 mJ / cm ² . After the exposure, the quartz mold was removed and the demolding force (F) at that time was measured. The mold release force (F) is measured according to the methods described in [0102] to [0107] of Japanese Patent Application Laid-Open No. 2011-206977, and is evaluated by S to E as follows. In addition, C or higher is a practical level.

S: F <12N

A: 12N ≦ F <13N

B: 13N ≦ F <15N

C: 15N ≦ F <20N

D: 20N ≦ F <30N

E: 30N ≦ F

<Stability evaluation after storage for 3 months with time>

After the curable composition for photoimprint was filled in the material cartridge for the inkjet printer DMP-2831 for 3 months, the inkjet ejection accuracy and mold release properties were evaluated.

As is clear from the results in the table, the hardenable compositions for photoimprinting in Examples 1 to 10 did not show inkjet ejection accuracy and mold release after comparison with the time before the test and three months later. Degradation shows good performance.

In particular, when R ¹ of the general formula (I) is an alkyl group, it can be seen that the ink jetting property is more excellent than that of an aryl group. In addition, by blending the compound represented by the general formula (II), the ink jet characteristics and the mold release properties are more effectively improved.

On the other hand, in the curable composition for photoimprint of Comparative Examples 1 and 2, the inkjet ejection accuracy and mold releasability were significantly deteriorated after 3 months.

The curable composition for photoimprint of Comparative Example 3 and Comparative Example 4 had a level of unsatisfactory releasability before the test over time.

As described above, according to the present invention, it is found that the polymerizable compound (A) and the photopolymerization initiator are contained in the curable composition for photoimprint. (B) and the fluorine-containing compound (C) represented by the general formula (I) can provide a hardenable composition for photoimprint, which is excellent in inkjet ejection accuracy and mold releasability, especially in terms of inkjet ejection accuracy and releasability. A curable composition for photoimprint that is excellent in stability over time.

In addition, it can be seen that if the viscosity of the curable composition of the present invention differs by 1 mPa. s, has a great impact on the effect of the present invention. In addition, it can be seen that even if the curable composition of the present invention has the same viscosity, if the surface tension is different by 3 mN / m, for example, the effect of the present invention is greatly affected.

Claims (15)

A curable composition for photoimprint, comprising a polymerizable compound, a photopolymerization initiator, and a fluorine-containing compound, and the fluorine-containing compound is represented by the following general formula (I); In the general formula (I), Rf ¹ represents a fluorine-containing alkyl group having 1 to 6 carbon atoms having 2 or more fluorine atoms; R ¹ represents an alkyl group having 1 to 7 carbon atoms or an aryl group having 6 to 8 carbon atoms; m represents an integer from 0 to 2, and n represents an integer from 1 to 3. When n represents 2 or 3, Rf ¹ may be different from each other. For example, the curable composition for photoimprint according to claim 1, which contains the fluorine-containing compound in an amount of 1 to 5 mass% with respect to all components other than the solvent. The hardenable composition for photoimprint according to claim 1 or 2, wherein in the general formula (I), Rf ¹ is a perfluoroalkyl group having 4 to 6 carbon atoms. The hardenable composition for photoimprint according to claim 1 or 2, wherein in the general formula (I), R ¹ is an alkyl group having 1 to 7 carbon atoms. The curable composition for photoimprint according to claim 1 or 2, wherein the polymerizable compound is a (meth) acrylate compound. For example, the curable composition for photoimprint according to claim 1 or 2, wherein the polymerizable compound contains 40 to 100% by mass of a polymerizable compound having two (meth) acrylate groups relative to the total polymerizable compound. . The curable composition for photoimprint according to claim 6, wherein the polymerizable compound is a polymerizable compound having one (meth) acrylate group at 10 to 45% by mass based on the total polymerizable compound. The curable composition for photoimprint according to claim 1 or 2, wherein the curable composition for photoimprint further contains a non-polymerizable compound having a polyalkylene glycol structure. The curable composition for photoimprint according to claim 8, wherein the non-polymerizable compound having a polyalkylene glycol structure is represented by the following general formula (II); In the general formula (II), Rf ² and Rf ³ each independently represent a fluorine-containing alkyl group having 1 to 6 carbon atoms having 2 or more fluorine atoms; p ¹ and p ² each independently represent an integer of 1 to 3, q ¹ and q ² each independently represent an integer of 0 to 2, r represents an integer of 2 to 4, and s represents 6 to 20. The curable composition for photoimprint according to claim 8 or 9, wherein the mass ratio of the fluorine-containing compound represented by the general formula (I) to the non-polymerizable compound having a polyalkanediol structure is 1: 5 ~ 5: 5. The curable composition for photoimprint according to claim 1 or 2, wherein the curable composition for photoimprint does not substantially contain a solvent. For example, the curable composition for photoimprinting according to item 1 or 2, wherein the viscosity of the curable composition for photoimprinting is 15 mPa at 23 ° C. s or less and the surface tension is 25 ~ 35mN / m. A pattern forming method comprising applying a hardenable composition for photoimprint according to any one of claims 1 to 12 on a substrate or a mold having a pattern, and sandwiching the light pressure between the mold and the substrate In the state of the curable composition for printing, light irradiation is performed. The pattern forming method according to claim 13, wherein the method of applying the curable composition for photoimprint on a substrate or a mold having a pattern is an inkjet method. A pattern obtained by a pattern forming method as claimed in claim 13 or 14.