JP6887563B2 - Underlayer film forming composition for imprint and its application - Google Patents

Description

The present invention relates to an imprint underlayer film forming composition, a kit, an imprint curable composition, a laminate, a method for producing a laminate, a pattern forming method, and a method for producing a semiconductor device.

The imprint method is a method of transferring a mold pattern to form a desired structure in a resin layer. Among them, according to the optical imprint method, a light-transmitting mold or a light-transmitting substrate is irradiated with light to photo-cure the curable composition, and then the mold is peeled off to transfer a fine pattern to the photo-cured product. be able to. Since this method enables imprinting at room temperature, it can be applied to the field of precision processing of ultrafine patterns such as the fabrication of semiconductor integrated circuits. Recently, new developments such as a nanocasting method that combines these advantages and a reversal imprint method for producing a three-dimensional laminated structure have been reported.
Inkjet coating has been studied as a method for coating a curable composition for imprint (for example, Patent Document 1). The curable composition for imprint is often dropped onto the substrate as droplets of about 1 to 100 pL. By adopting inkjet coating, the coating amount can be adjusted according to the density of the imprint pattern, and a uniform imprint pattern can be secured. In order to further strengthen the adhesion of the imprint layer formed from the curable composition for imprint to the substrate, an underlayer film formed from the underlayer film forming composition for imprint between the two (Patent Document). There are examples in which 2 and 3) and an adhesive layer (Patent Documents 4 and 5) are applied.

Japanese Patent Application Laid-Open No. 2005-533393 Japanese Unexamined Patent Publication No. 2013-093552 Japanese Unexamined Patent Publication No. 2014-093385 Japanese Unexamined Patent Publication No. 2016-146468 JP-A-2017-206695

In the optical imprint method, as described above, the curable composition for imprint is applied to the surface of the substrate, and the curable composition for imprint is cured by irradiating light with the mold in contact with the surface. Form an imprint layer. Then, the step of peeling off the mold is included. In the process of peeling the mold, the imprint layer (cured product) may peel off from the substrate and adhere to the mold. It is considered that one of the causes is that the adhesive force between the substrate and the imprint layer is not sufficiently high with respect to the adhesive force between the mold and the imprint layer. In order to solve such a problem, for example, the techniques described in Patent Documents 2 to 5 have been proposed, and a certain solution has been achieved by this. However, with the expansion of the use of the imprint method and the activation of product development using this method, in addition to ensuring the adhesion between the substrate and the imprint layer, it is necessary to ensure the adhesion to various substrates. Is becoming important.
Therefore, the present invention relates to an imprint underlayer film forming composition capable of ensuring sufficient adhesion to various substrates, a kit using this imprint underlayer film forming composition, and curing for imprinting. It is an object of the present invention to provide a sex composition, a laminate, a method for producing a laminate, a pattern forming method, and a method for producing a semiconductor device.

Based on the above problems, the present inventors have proceeded with research on a technique for utilizing an underlayer film forming composition for imprinting in an imprinting method. Then, they have found that the above-mentioned problems can be solved by using a polymer having a polymerizable group and an acidic partial structure having a low pKa as a polymer to be contained in the underlayer film forming composition for imprinting. Specifically, the above-mentioned problems have been solved by the means according to the following <1> and the means according to the preferred embodiments <2> to <23>.

<1> Imprint underlayer film forming composition containing a polymer and a solvent, wherein the polymer contains a structural unit derived from a monomer having a pKa of 4.0 or less and a polymerizable group. Stuff.
<2> The underlayer film forming composition for imprint according to <1>, wherein the polymer is an acrylic resin.
<3> The underlayer film forming composition for imprint according to <1> or <2>, wherein the weight average molecular weight of the polymer is 2,000 or more.
<4> The underlayer film forming composition for imprint according to any one of <1> to <3>, wherein the polymerizable group of the polymer is a (meth) acryloyl group.
<5> The imprint according to any one of <1> to <4>, wherein the structural unit derived from a monomer having a pKa of 4.0 or less contained in the polymer is a structural unit derived from a monomer having a pKa of 3.0 or less. Underlayer film forming composition for printing.
<6> The structural unit derived from the monomer of pKa 4.0 or less is composed of a hydroxyl group, a carboxyl group, a thiocarboxylic acid group, a dithiocarboxylic acid group, a sulfonic acid group, a phosphoric acid monoester group, a phosphoric acid diester group and a phosphoric acid group. The underlayer film forming composition for imprint according to any one of <1> to <5>, which comprises at least one selected from the group.
<7> The underlayer film forming composition for imprint according to any one of <1> to <6>, wherein 99.0% by mass or more of the underlayer film forming composition for imprint is a solvent.
<8> The underlayer film forming composition for imprint according to any one of <1> to <7>, wherein the polymer has a structural unit having a polymerizable group.
<9> A kit containing the imprint underlayer film forming composition and the imprint curable composition according to any one of <1> to <8>.
<10> A curable composition for imprinting used in the kit according to <9>.
<11> On the surface of the substrate, the underlayer film formed from the underlayer film forming composition for imprint according to any one of <1> to <8>, which is located on the surface of the substrate, and the surface of the underlayer film. A laminate having an imprint layer formed from a curable composition for imprint located.
<12> The laminate according to <11>, wherein a substrate having an organic layer as the outermost layer is used as the substrate.
<13> The laminate according to <11> or <12>, wherein a substrate having a basic layer as the outermost layer is used as the substrate.
<14> A step of applying the imprint underlayer film forming composition according to any one of <1> to <8> to the surface of a substrate to form an imprint underlayer film, the step of forming an imprint underlayer film on the surface of the underlayer film. A method for producing a laminate, which comprises a step of applying a curable composition for printing.
<15> The method for producing a laminate according to <14>, wherein a substrate having an organic layer as the outermost layer is used as the substrate.
<16> The method for producing a laminate according to <14> or <15>, wherein a substrate having a basic layer as the outermost layer is used as the substrate.
<17> A step of forming a lower layer film on the surface of a substrate using the lower layer film forming composition for imprint according to any one of <1> to <8>, a lower layer film for imprinting on the lower layer film. A step of applying the forming composition to form a curable composition layer for imprint, a step of bringing a mold into contact with the curable composition layer for imprint, and a step of bringing the mold into contact with the curable for imprint. A pattern forming method comprising a step of exposing a composition layer and a step of peeling the mold from the exposed curable composition layer for imprinting.
<18> The pattern forming method according to <17>, wherein a substrate having an organic layer as the outermost layer is used as the substrate.
<19> The pattern forming method according to <17> or <18>, wherein a substrate having a basic layer as the outermost layer is used as the substrate.
<20> The pattern forming method according to any one of <17> to <19>, wherein the underlayer film forming composition for imprint is applied to the surface of a substrate by a spin coating method.
<21> The pattern forming method according to any one of <17> to <20>, wherein the curable composition for imprint is applied onto an underlayer film by an inkjet method.
<22> A method for manufacturing a semiconductor device, which comprises the pattern forming method according to any one of <17> to <21>.

According to the underlayer film forming composition for imprinting of the present invention, sufficient adhesion to various substrates can be ensured. Further, it has become possible to provide a kit using this underlayer film forming composition for imprinting, a curable composition for imprinting, a laminate, a method for producing a laminate, a pattern forming method, and a method for producing a semiconductor device.

It is a process explanatory drawing which shows an example of the manufacturing process in the case of forming a cured product pattern, and using the obtained cured product pattern for processing a substrate by etching.

Hereinafter, the contents of the present invention will be described in detail. In addition, in this specification, "~" is used in the meaning which includes the numerical values described before and after it as the lower limit value and the upper limit value.
As used herein, "(meth) acrylate" refers to acrylate and methacrylate.
As used herein, "imprint" preferably refers to a pattern transfer having a size of 1 nm to 10 mm, and more preferably a pattern transfer having a size of about 10 nm to 100 μm (nanoimprint).
In the notation of a group (atomic group) in the present specification, the notation that does not describe substitution and non-substitution includes those having no substituent as well as those having 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).
In the present specification, "light" includes not only light having wavelengths in the ultraviolet, near-ultraviolet, far-ultraviolet, visible, and infrared regions, and electromagnetic waves, but also radiation. Radiation includes, for example, microwaves, electron beams, extreme ultraviolet rays (EUV), and X-rays. Further, laser light such as a 248 nm excimer laser, a 193 nm excimer laser, and a 172 nm excimer laser can also be used. As these lights, monochrome light (single wavelength light) that has passed through an optical filter may be used, or light having a plurality of different wavelengths (composite light) may be used.
Unless otherwise specified, the weight average molecular weight (Mw) in the present invention refers to those measured by gel permeation chromatography (GPC).
Unless otherwise specified, the temperature in the present invention is 23 ° C.
The boiling point in the present invention means the boiling point at 1 atm (1 atm = 1013.25 hPa).

The underlayer film forming composition for imprint of the present invention is an underlayer film forming composition for imprint containing a polymer and a solvent, and the polymer contains a structural unit derived from a monomer having a pKa of 4.0 or less and a polymerizable group. (In the present specification, this polymer is referred to as a specific polymer). As a result, good adhesion between the imprint layer and the substrate can be realized. In particular, according to the preferred embodiment, it is possible to realize a low-defect imprint process that does not depend on the substrate type.

<Specific polymer>
The specific polymer used in the present invention contains a monomer-derived structural unit having a pKa of 4.0 or less.
The pKa of the monomer is preferably 3.0 or less, more preferably 2.5 or less, and even more preferably 2.0 or less. As a lower limit value, it is practical that it is −3.0 or more, and further, 1.0 or more.

In the present specification, pKa represents pKa in an aqueous solution, and is a value calculated by the method described in Examples described later.

The constituent units derived from the monomers having a pKa of 4.0 or less are a hydroxyl group (alcoholic hydroxyl group, phenolic hydroxyl group), a carboxyl group, an amide group, an imide group, a urea group, a urethane group, a cyano group, and an ether group (preferably poly). At least one selected from the group consisting of an alkyleneoxy group), a cyclic ether group, a lactone group, a sulfonyl group, a sulfonic acid group, a sulfonamide group, a sulfonimide group, a phosphoric acid group, a phosphoric acid ester group and a nitrile group (hereinafter, It is preferable to include (sometimes referred to simply as an "acid group"). Among these, it may have at least one selected from the group consisting of a hydroxyl group, a carboxyl group, a thiocarboxylic acid group, a dithiocarboxylic acid group, a sulfonic acid group, a phosphoric acid monoester group, a phosphoric acid diester group, and a phosphoric acid group. It is more preferable to contain at least one selected from the group consisting of a sulfonic acid group, a phosphoric acid monoester group, a phosphoric acid diester group, and a phosphoric acid group.

The monomer having a pKa of 4.0 or less preferably has a molecular weight of 50 or more, more preferably 100 or more, further preferably 150 or more, and further preferably 200 or more. Further, the molecular weight is preferably 1000 or less, more preferably 800 or less, further preferably less than that, and even more preferably 600 or less. Within such a range, the effects of improving the film-forming property and the adhesiveness are more effectively exhibited.

Examples of the polymerizable group contained in the monomer having a pKa of 4.0 or less include a (meth) acryloyl group, an epoxy group, an oxetane group, a methylol group, a methylol ether group, and a vinyl ether group. From the viewpoint of easiness of polymerization, a (meth) acryloyl group is particularly preferable. In the present specification, the polymerizable groups specified and exemplified here are referred to as polymerizable groups Ps.

The monomer having a pKa of 4.0 or less preferably has a structure represented by an acid group-linking group-polymerizable group. Examples of the linking group here include the linking group L described later.

In the specific polymer, the ratio of the constituent units derived from the monomers having a pKa of 4.0 or less in all the constituent units is preferably 0.5% by mass or more based on the molar ratio when each constituent unit is used as a monomer. It is more preferably 3% by mass or more, and further preferably 3% by mass or more. The upper limit is preferably 50% by mass or less, more preferably 30% by mass or less, and further preferably 15% by mass or less.
The specific polymer may contain only one type of structural unit derived from a monomer having a pKa of 4.0 or less, or may contain two or more types. When two or more types are included, the total amount is preferably in the above range.

The specific polymer has a polymerizable group.
The polymerizable group may be attached to the side chain of the specific polymer or to the end. In the present invention, it is preferable that the specific polymer has a structural unit having a polymerizable group. Further, in the specific polymer, the structural unit derived from the monomer of pKa 4.0 or less may also contain a polymerizable group, or the structural unit having a polymerizable group in addition to the structural unit derived from the monomer of pKa 4.0 or less. May be contained, and it is preferable that a structural unit having a polymerizable group is contained in addition to the structural unit derived from the monomer having a pKa of 4.0 or less.
Specific examples of the polymerizable group include polymerizable groups Ps, and a (meth) acryloyl group is particularly preferable. The polymerizable group is preferably introduced into the polymer in a form incorporated into the structural unit. Since the specific polymer has a polymerizable group, the lower layer film for imprinting forms a crosslinked structure, prevents cohesive failure of the lower layer film at the time of peeling, and makes it possible to secure more effective adhesion. preferable.
In the specific polymer, the ratio of the structural units having a polymerizable group to all the structural units is preferably 50% by mass or more, preferably 70% by mass or more, based on the molar ratio when each structural unit is used as a monomer. More preferably, it is more preferably 85% by mass or more. The upper limit is preferably 99.5% by mass or less, more preferably 99% by mass or less, and further preferably 97% by mass or less.
The specific polymer may contain only one type of structural unit having a polymerizable group, or may contain two or more types. When two or more types are included, the total amount is preferably in the above range.

In the specific polymer, the total ratio of the structural unit having an acid group and the structural unit having a polymerizable group in all the structural units shall be 90% by mass or more based on the molar ratio when each structural unit is used as a monomer. Is more preferable, 95% by mass or more is more preferable, and 97% by mass or more is further preferable. The upper limit may be 100% by mass.

The specific polymer is preferably at least one selected from the group consisting of acrylic resin, novolak resin, epoxy resin, polyurethane resin, phenol resin, polyester resin and melamine resin, and is composed of acrylic resin, polyester resin and novolak resin. It is more preferably at least one selected from the group, and even more preferably an acrylic resin.

The acrylic resin is generally a polymer of acrylic acid, acrylic acid ester, and methacrylic acid ester, or a monomer having these as main components and copolymerizable with these, for example, styrene, vinyltoluene, vinyl acetate, and acrylonitrile. Refers to resin. Acrylic resins can be synthesized by addition polymerization of acrylic monomers. Addition polymerization is triggered by radicals, cations and anionics, which are called radical polymerization, cationic polymerization and anionic polymerization, respectively. The most industrially used is radical polymerization. Examples of acrylic monomers include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, propyl (meth) acrylic acid, isopropyl (meth) acrylic acid, n-butyl (meth) acrylic acid, and i (meth) acrylic acid. Examples thereof include -butyl, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylexyl (meth) acrylate, and lauryl (meth) acrylate.

Phenol resins are produced by the reaction of phenol, which is a trifunctional monomer (which may be bi- or monofunctional with substituted phenol), and formaldehyde, which is a bifunctional monomer, under an acid or base catalyst. What is obtained by an acid catalyst is called novolac, and what is obtained by a base catalyst is called resol. Resol self-cures when heated. Novolac cures when heated with a curing agent such as hexamethylenetetramine (HMTA). As raw materials, phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3, Examples thereof include 5-xylenol, resosinol, pt-butylphenol, p-nonylphenol, and bisphenol.
Melamine sealant is a thermosetting synthetic resin obtained by addition condensation of melamine (2,4,6-triamino-1,3,5-triazine) and formaldehyde. It is counted as one of the amino resins because it uses an amino group (-NH _{2) as a reactive group together with urea resin and the like.} It is transparent, hard, and has excellent coloring, heat resistance, and arc resistance, so it has a wide range of uses such as molding materials, decorative boards, and paints. Melamine reacts with formaldehyde using an amino group as a reactive group to become methylol melamine. As for methylol melamine, all substitutions from monomethylol melamine to hexamethylol melamine are easily obtained as a mixture.

Epoxy resin is a general term for compounds having two or more epoxy groups in one molecule, and usually does not cure even when heated by itself, and a curing agent or catalyst is required to obtain a cured product. By adding a curing agent, an addition reaction is carried out to obtain an insoluble and infusible thermosetting resin, so that volatile substances are not generated and workability is good. Various primary and secondary amines, acid anhydrides, and phenol resins can be used as the curing agent. The epoxy resin is produced by two methods: a reaction between a compound having active hydrogen and epichlorohydrin, and oxidation of a compound having a double bond. Compounds with active hydrogen include 2,2-bis (4-hydroxyphenyl) propane (also known as bisphenol A), 4,4'-dihydroxydiphenylmethane (also known as bisphenol F), and 2,2-bis (3,5-dibromo). -4-Hydroxyphenyl) propane (also known as tetrabromobisphenol A), orthocresol, hexahydrophthalic acid, metaaminophenol, paraaminophenol can be mentioned. As other epoxy resin raw materials, novolak type phenol resin, dimer acid, polybutadiene, soybean oil, alicyclic compound, tetrahydrophthalic acid, p-hydroxybenzoic acid, m-xylylene diamine, hydantin compound, cyanuric acid and the like are used. Be done.

The polyester resin is obtained by a polycondensation reaction of a dibasic acid and a dihydric alcohol, and has an ester bond (-COO-) in the main chain. Examples of the dibasic acid include terephthalic acid, naphthalenedicarboxylic acid, cyclohexanedicarboxylic acid, adipic acid, maleic anhydride, fumaric acid, itaconic acid and the like. Propylene glycol, ethylene glycol, and diethylene glycol are often used as the basic acid polyhydric alcohol. However, other dihydric alcohols may be used as appropriate depending on the properties of the resin. In addition to PET (polyethylene terephthalate), polyesters that can be generally used as plastic materials include polyptylene terephthalate (PBT) in which the ethylene glycol component of PET is replaced with tetramethylene glycol, and polycyclohexanedimethylene tereph in which cyclohexanedimethanol is replaced. There is tarate (PCT), and polyethylene-2,6 naphthalate (PEN) in which the terephthalic acid component is replaced with 2,6-naphthalenedicarboxylic acid is also known.

Polyurethane (PU) is a group of polymers having urethane bonds (carbamic acid ester bonds) obtained by the reaction of polyisocyanates with polyols. When each of the reacting compounds is bifunctional, a linear thermoplastic PU is obtained, and when at least one of them is trifunctional or higher, or when a side chain reaction occurs, a PU having a network structure is formed.

For each of the above resins, you can also refer to "Plastic Dictionary" (Asakura Shoten) edited by Keizo Miyasaka and others.

Ｒ^１は水素原子またはメチル基であり、メチル基が好ましい。
Ｘ^Ｒは酸素原子またはＮＨであり、酸素原子が好ましい。
ｎは１〜３の整数であり、１または２が好ましく、１がより好ましい。
ｍは１〜５の整数であり、１または２が好ましく、１がより好ましい。
Ｒは、ｐＫａ４．０以下となる部分構造（酸基）であることが好ましい。式（１）〜式（６）におけるＲが２つ以上ある場合、複数のＲは互いに結合して環を形成していてもよい。酸基の好ましいものは、上述したｐＫａ４．０以下のモノマーが有する酸基と同じである。
式（１）〜（６）において、主鎖やベンゼン環は本発明の効果を奏する範囲内で後述する置換基Ｔを有していてもよい。また、Ｒや置換基Ｔは主鎖と結合して環を形成していてもよい。The specific polymer preferably has a main chain represented by a structural unit represented by any of the following formulas (1) to (6).

R ¹ is a hydrogen atom or a methyl group, preferably a methyl group.
X ^R is an oxygen atom or NH, preferably an oxygen atom.
n is an integer of 1 to 3, preferably 1 or 2, and more preferably 1.
m is an integer of 1 to 5, preferably 1 or 2, and more preferably 1.
R preferably has a partial structure (acid group) having a pKa of 4.0 or less. When there are two or more Rs in the formulas (1) to (6), the plurality of Rs may be combined with each other to form a ring. The preferred acid group is the same as that of the above-mentioned monomer having pKa 4.0 or less.
In the formulas (1) to (6), the main chain and the benzene ring may have a substituent T, which will be described later, within the range in which the effect of the present invention is exhibited. Further, R and the substituent T may be bonded to the main chain to form a ring.

Ｒ^１は水素原子またはメチル基であり、メチル基が好ましい。
Ｘ^Ｒは酸素原子またはＮＨであり、酸素原子が好ましい。
ｎは１〜３の整数であり、１または２が好ましく、１がより好ましい。
ｍは１〜５の整数であり、１または２が好ましく、１がより好ましい。
Ｒ^２はそれぞれ独立に重合性基を含む置換基である。Ｒ^２に含まれる重合性基は上記Ｐｓであることが好ましい。式（１−１）〜式（１−６）におけるＲ^２が２つ以上ある場合、複数のＲ^２は互いに結合して環を形成していてもよい。また、式（１−１）〜式（１−６）の主鎖およびベンゼン環には本発明の効果を奏する範囲で置換基Ｔが置換していてもよい。
Ｒ^２としては下記式（Ｔ２）であることが好ましい。Ｒ^２の式量は、８０以上１０００以下が好ましく、１００以上８００以下がより好ましく、１５０以上６００以下がさらに好ましい。
−（Ｌ^４）_ｎ６−（Ｐ）_ｎ７ （Ｔ２）
Ｌ^４は下記の連結基Ｌであり、なかでもアルキレン基、アリーレン基、(オリゴ)アルキレンオキシ基、カルボニル基、酸素原子、これらの組合せに係る連結基が好ましい。ｎ６は０または１であり、１が好ましい。Ｐは重合性基を含む基であり、ＰｓまたはＰｓと連結基Ｌで構成された基が好ましい。ｎ７は１〜６の整数であり、１または２が好ましい。なお、ｎ７が２以上であるときは、Ｌ^４が３価以上の連結基となっていればよく、例えば、３価以上のアルカン構造の基（炭素数１〜１２が好ましく、１〜６がより好ましく、１〜３がさらに好ましい）、アルケン構造の基（炭素数２〜１２が好ましく、２〜６がより好ましく、２〜３がさらに好ましい）、またはアリール構造の基（炭素数６〜２２が好ましく、６〜１８がより好ましく、６〜１０がさらに好ましい）を含む連結基が挙げられる。なお、(オリゴ)アルキレンオキシ基とは、モノアルキレンオキシ基でも、オリゴアルキレンオキシ基でもよいことを意味する。Ｌ^４の連結原子数は、１〜２４が好ましく、１〜１２がより好ましく、１〜６がさらに好ましい。
特定ポリマーが式（１）で表される構成単位を含み、コポリマーである場合、式（１−１）で表される構成単位を含むことが好ましい。式（２）〜式（６）についても、同様に、それぞれ、式（１−２）〜式（１−６）で表される構成単位を含むことが好ましい。The specific polymer is also preferably a copolymer. The copolymerization component preferably contains at least one of the structural units represented by any of the following formulas (1-1) to (1-6) together with the structural units of the above formulas (1) to (6). ..

R ¹ is a hydrogen atom or a methyl group, preferably a methyl group.
X ^R is an oxygen atom or NH, preferably an oxygen atom.
n is an integer of 1 to 3, preferably 1 or 2, and more preferably 1.
m is an integer of 1 to 5, preferably 1 or 2, and more preferably 1.
R ² is a substituent containing a polymerizable group independently. The polymerizable group contained in ^{R 2 is preferably Ps. If R 2} in the formula (1-1) to Formula (1-6) there are two or more, plural ^{R 2} may be bonded to each other to form a ring. Further, the main chain and the benzene ring of the formulas (1-1) to (1-6) may be substituted with the substituent T within the range in which the effect of the present invention is exhibited.
It is preferred as R ² is the following formula (T2). Formula weight of R ² is preferably 80 to 1,000, more preferably 100 or more 800 or less, more preferably 150 or more and 600 or less.
-(L ⁴ ) _n6- (P) _n7 (T2)
L ⁴ is the following linking group L, and among them, an alkylene group, an arylene group, a (oligo) alkyleneoxy group, a carbonyl group, an oxygen atom, and a linking group related to a combination thereof are preferable. n6 is 0 or 1, preferably 1. P is a group containing a polymerizable group, and a group composed of Ps or Ps and a linking group L is preferable. n7 is an integer of 1 to 6, preferably 1 or 2. Incidentally, when n7 is 2 or more, it is sufficient that L ⁴ is a trivalent or more connecting group, for example, group (1 to 12 carbon atoms are preferable tri- or higher alkane structure, 1 to 6 More preferably, 1 to 3 is more preferable), an alkene structure group (2 to 12 carbon atoms is preferable, 2 to 6 is more preferable, and 2 to 3 is more preferable), or an aryl structure group (6 to 22 carbon atoms is preferable). , 6-18 is more preferred, and 6-10 is even more preferred). The (oligo) alkyleneoxy group means that it may be a monoalkyleneoxy group or an oligoalkyleneoxy group. The ^{number of linked atoms of L 4} is preferably 1 to 24, more preferably 1 to 12, and even more preferably 1 to 6.
When the specific polymer contains a structural unit represented by the formula (1) and is a copolymer, it preferably contains a structural unit represented by the formula (1-1). Similarly, it is preferable that the formulas (2) to (6) also include the structural units represented by the formulas (1-2) to (1-6), respectively.

The specific polymer also preferably contains a structural unit that does not have an acid group and a polymerizable group (sometimes referred to as "another structural unit"). The other structural unit preferably has the skeletons of the above formulas (1-1) to (1-6). However, the substituent R ^{2 is a substituent R 3} having no acid group and a polymerizable group. Further, the substituent T may be substituted in the other main chain or the benzene ring as long as the effect of the present invention is exhibited. Also, it may be R ³ or substituent T is bonded to the main chain to form a ring.
R ³ is preferably given the following formula (T3). The formula amount of R ³ is preferably 80 or more and 1000 or less, more preferably 100 or more and 800 or less, and further preferably 150 or more and 600 or less.
_{^{- (L 5) n8 - (}} T 1) n9 (T3)
L ⁵ is a linking group L described later, and among them, an alkylene group, an arylene group, a (oligo) alkyleneoxy group, a carbonyl group, an oxygen atom, and a linking group related to a combination thereof are preferable. The ^{number of linked atoms of L 5} is preferably 1 to 24, more preferably 1 to 12, and even more preferably 1 to 6. n8 is 0 or 1. T ¹ is a substituent T described later, and among them, an alkyl group that may be substituted with a halogen atom, an aryl group that may be substituted with a halogen atom, and an arylalkyl group that may be substituted with a halogen atom. Is preferable. n9 is an integer of 1 to 6, preferably 1 or 2. When n9 is 2 or more has only to which L ⁵ is trivalent or more connecting group, for example, group (1 to 12 carbon atoms are preferable tri- or higher alkane structure, and more preferably 1 to 6 , 1-3 are more preferred), alkene-structured groups (preferably 2-12 carbon atoms, more preferably 2-6, more preferably 2-3), or aryl-structured groups (preferably 6-22 carbon atoms). , 6-18 is more preferred, 6-10 is even more preferred).

As the substituent T, an alkyl group (preferably 1 to 24 carbon atoms, more preferably 1 to 12 carbon atoms, further preferably 1 to 6 carbon atoms) and an arylalkyl group (preferably 7 to 21 carbon atoms, more preferably 7 to 15 carbon atoms). , 7-11 is more preferred), an alkenyl group (preferably 2 to 24 carbon atoms, more preferably 2 to 12 and even more preferably 2 to 6), an alkynyl group (preferably 2 to 12 carbon atoms, 2 to 6 carbon atoms). More preferably, 2-3), hydroxyl group, amino group (preferably 0 to 24 carbon atoms, more preferably 0 to 12 and even more preferably 0 to 6), thiol group, carboxyl group, aryl group (carbon). Numbers 6 to 22 are preferred, 6 to 18 are more preferred, 6 to 10 are even more preferred), heteroaryl groups (1 to 22 carbon atoms are preferred, 1 to 16 are more preferred, 1 to 12 are even more preferred), alkoxyls. Group (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1-3), aryloxy group (preferably 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, still more preferably 6 to 10 carbon atoms). ), Acrylic group (preferably 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, further preferably 2 to 3), acyloxy group (preferably 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, 2 to 3 carbon atoms). More preferably), an allyloyl group (preferably 7 to 23 carbons, more preferably 7 to 19 and even more preferably 7 to 11), an allyloyloxy group (preferably 7 to 23 carbons, more preferably 7 to 19). 7 to 11 are more preferable), carbamoyl group (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 3), sulfamoyl group (preferably 0 to 12 carbon atoms, 0 to 6 carbon atoms are more preferable). Preferably, 0 to 3 are more preferable), a sulfo group, an alkylsulfonyl group (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 6 carbon atoms), and an arylsulfonyl group (6 to 22 carbon atoms are preferable). Preferably, 6 to 18 is more preferable, 6 to 10 is more preferable), a heterocyclic group (1 to 12 carbon atoms is preferable, 1 to 8 is more preferable, 2 to 5 is more preferable, and a 5-membered ring or a 6-membered ring is preferable. (Preferably containing), (meth) acryloyl group, (meth) acryloyloxy group, halogen atom (eg, fluorine atom, chlorine atom, bromine atom, iodine atom), oxo group (= O), imino group (= NR) ^N), an alkylidene group _{^{(= C (R N) 2}} ) , and the like.
^RN is a hydrogen atom, an alkyl group (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 6 carbon atoms), and an alkenyl group (preferably 2 to 12 carbon atoms, 2 to 6 carbon atoms are more preferable). Preferably, 2-3 are more preferred), alkynyl groups (2-12 carbon atoms are preferred, 2-6 are more preferred, 2-3 are more preferred), aryl groups (6-22 carbon atoms are preferred, 6-18 carbon atoms are preferred). Is more preferable, 6 to 10 is more preferable), a heteroaryl group (carbon number 1 to 22 is preferable, 1 to 16 is more preferable, 1 to 12 is more preferable), and among them, a hydrogen atom, a methyl group, and the like. An ethyl group or a propyl group is preferable. R ^N may have a respective group defined by substituent T to the extent that the effects of the present invention.
The alkyl moiety, alkenyl moiety, and alkynyl moiety contained in each substituent may be chain or cyclic, and may be linear or branched. When the substituent T is a group capable of taking a substituent, it may further have a substituent T. For example, the alkyl group may be an alkyl halide group, a (meth) acryloyloxyalkyl group, an aminoalkyl group or a carboxyalkyl group.

As the linking group L, an alkylene group (preferably 1 to 24 carbon atoms, more preferably 1 to 12 carbon atoms, further preferably 1 to 6 carbon atoms) and an alkenylene group (preferably 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms). 2-3 are more preferred), alkynylene groups (2-12 carbon atoms are preferred, 2-6 are more preferred, 2-3 are more preferred), (oligo) alkyleneoxy groups (alkylene groups in one building block. The number of carbon atoms is preferably 1-12, more preferably 1-6, still more preferably 1-3; the number of repetitions is preferably 1-50, more preferably 1-40, even more preferably 1-30), arylene group ( 6 to 22 carbon atoms are preferred, 6 to 18 are more preferred, 6 to 10 are even more preferred), oxygen atoms, sulfur atoms, sulfonyl groups, carbonyl groups, thiocarbonyl groups, -NR ^N- , and combinations thereof. Linking groups can be mentioned. The alkylene group may have the following substituent T. For example, the alkylene group may have a hydroxyl group. The number of atoms contained in the linking group L is preferably 1 to 50, more preferably 1 to 40, and even more preferably 1 to 30, excluding hydrogen atoms. The number of linked atoms means the number of atoms located in the shortest path among the atomic groups involved in the linking. For example, in the case of -CH _2- (C = O) -O-, the number of atoms involved in the connection is 6, and even excluding the hydrogen atom, it is 4. On the other hand, the shortest atom involved in the connection is -C-C-O-, which is three. The number of connected atoms is preferably 1 to 24, more preferably 1 to 12, and even more preferably 1 to 6. The alkylene group, alkenylene group, alkynylene group, and (oligo) alkyleneoxy group may be chain or cyclic, and may be linear or branched.

The specific polymer preferably has a weight average molecular weight of 2,000 or more, more preferably 3,000 or more, further preferably 4,000 or more, further preferably 6,000 or more, and 10,000 or more. Even more preferably, 15,000 or more is particularly preferable. The upper limit of the weight average molecular weight is not particularly specified, but for example, 200,000 or less is preferable, 100,000 or less is more preferable, 70,000 or less is further preferable, 50,000 or less is further preferable, and 35,000 or less. May be. By setting the weight average molecular weight to the above lower limit value or more, the film stability during the baking process can be improved, and the surface shape during the formation of the imprint underlayer film can be further improved. Further, by setting the weight average molecular weight to the above upper limit value or less, the solubility in a solvent becomes high, and the application by spin coating or the like becomes easier. When the above molecular weight is in an appropriate range, the fluidity is maintained and the wettability of the curable composition for imprinting is improved.
The specific polymer preferably has a dispersity (Mw / Mn) of 3.0 or less, and more preferably 2.5 or less. The lower limit of the dispersity may be 1.0, but even if it is 1.5 or more, it is a sufficiently practical level.

The content of the specific polymer in the underlayer film forming composition for imprint is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and 0.1% by mass or more. It is more preferable to have. The upper limit is preferably 10% by mass or less, more preferably 7% by mass or less, further preferably 5% by mass or less, further preferably 4% by mass or less, and 3% by mass. % Or less is even more preferable, and it may be 1% by mass or less, or 0.7% by mass or less.
The content of the specific polymer in the non-volatile component (meaning a component other than the solvent in the composition, the same applies hereinafter) is preferably 5% by mass or more, more preferably 20% by mass or more, and 30% by mass. % Or more, more preferably 50% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, and 95% by mass or more. It may be 99% by mass or more. The upper limit may be 100% by mass.
By setting this amount to the above lower limit value or more, the effect of blending the polymer can be suitably exhibited, and a uniform thin film can be easily prepared. On the other hand, when the value is not more than the above upper limit, the effect of using the solvent is preferably exhibited, and it becomes easy to form a uniform film over a wide area.
Only one type of specific polymer may be used, or two or more types may be used. When two or more types are used, the total amount is preferably in the above range.

Examples of the specific polymer include the following polymers, but the present invention is not construed as being limited thereto. The crosslinkable unit in the table corresponds to the structural unit having the above-mentioned polymerizable group Ps (for example, formulas (1-1) to (1-6)), and the acidic unit is derived from the above-mentioned monomer of pKa4.0 or less. Corresponds to the structural unit of (for example, equations (1) to (6)).

<Solvent>
The underlayer film forming composition for imprint contains a solvent (hereinafter, may be referred to as "solvent for underlayer film"). The solvent is, for example, a compound that is liquid at 23 ° C. and has a boiling point of 250 ° C. or lower. Usually, the non-volatile component finally forms the underlayer film. The underlayer film forming composition for imprint preferably contains the solvent for the underlayer film in an amount of 99.0% by mass or more, more preferably 99.5% by mass or more, and may contain 99.6% by mass or more. In the present invention, the liquid means that the viscosity at 23 ° C. is 100,000 mPa · s or less. By setting the ratio of the solvent in the above range, the film thickness at the time of film formation is kept thin, which leads to the improvement of the pattern formation property at the time of etching processing.
The solvent may be contained in only one kind or two or more kinds in the underlayer film forming composition for imprinting. When two or more types are included, the total amount is preferably in the above range.
The boiling point of the solvent for the underlayer film is preferably 230 ° C. or lower, more preferably 200 ° C. or lower, further preferably 180 ° C. or lower, further preferably 160 ° C. or lower, and 130 ° C. or lower. Is even more preferable. It is practical that the lower limit is 23 ° C, but it is more practical that it is 60 ° C or higher. By setting the boiling point in the above range, the solvent can be easily removed from the underlayer film, which is preferable.

The solvent for the underlayer film is preferably an organic solvent. The solvent is preferably a solvent having at least one of an ester group, a carbonyl group, a hydroxyl group and an ether group. Of these, it is preferable to use an aprotic polar solvent.

As specific examples, alkoxy alcohols, propylene glycol monoalkyl ether carboxylates, propylene glycol monoalkyl ethers, lactic acid esters, acetate esters, alkoxypropionic acid esters, chain ketones, cyclic ketones, lactones, and alkylene carbonates are selected.

Examples of the alkoxy alcohol include methoxyethanol, ethoxyethanol, methoxypropanol (for example, 1-methoxy-2-propanol), ethoxypropanol (for example, 1-ethoxy-2-propanol), and propoxypropanol (for example, 1-propanol-2-. (Propanol), methoxybutanol (eg 1-methoxy-2-butanol, 1-methoxy-3-butanol), ethoxybutanol (eg 1-ethoxy-2-butanol, 1-ethoxy-3-butanol), methylpentanol (For example, 4-methyl-2-pentanol) and the like.

As the propylene glycol monoalkyl ether carboxylate, at least one selected from the group consisting of propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, and propylene glycol monoethyl ether acetate is preferable, and propylene glycol monomethyl ether acetate (propylene glycol monomethyl ether acetate). PGMEA) is particularly preferable.

Further, as the propylene glycol monoalkyl ether, propylene glycol monomethyl ether (PGME) or propylene glycol monoethyl ether is preferable.
As the lactate ester, ethyl lactate, butyl lactate, or propyl lactate is preferable.
As the acetic acid ester, methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, propyl acetate, isoamyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, or 3-methoxybutyl acetate are preferable.
As the alkoxypropionate ester, methyl 3-methoxypropionate (MMP) or ethyl 3-ethoxypropionate (EEP) is preferable.
Chain ketones include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutylketone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone, Acetoneacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methylnaphthyl ketone or methyl amyl ketone are preferred.
As the cyclic ketone, methylcyclohexanone, isophorone or cyclohexanone is preferable.
As the lactone, γ-butyrolactone (γBL) is preferable.
As the alkylene carbonate, propylene carbonate is preferable.

In addition to the above components, it is preferable to use an ester solvent having 7 or more carbon atoms (preferably 7 to 14, more preferably 7 to 12 and even more preferably 7 to 10) and having a heteroatom number of 2 or less.

Preferred examples of ester solvents having 7 or more carbon atoms and 2 or less heteroatoms include amyl acetate, 2-methylbutyl acetate, 1-methylbutyl acetate, hexyl acetate, pentyl propionate, hexyl propionate, butyl propionate, and the like. Examples thereof include isobutyl isobutyrate, heptyl propionate, butyl butanoate, and the like, and isoamyl acetate is particularly preferable.

It is also preferable to use a solvent having a flash point (hereinafter, also referred to as p component) of 30 ° C. or higher. Examples of such components include propylene glycol monomethyl ether (p component: 47 ° C.), ethyl lactate (p component: 53 ° C.), ethyl 3-ethoxypropionate (p component: 49 ° C.), and methylamyl ketone (p component: 49 ° C.). 42 ° C.), cyclohexanone (p component: 30 ° C.), pentyl acetate (p component: 45 ° C.), methyl 2-hydroxyisobutyrate (p component: 45 ° C.), γ-butyrolactone (p component: 101 ° C.) or propylene carbonate. (P component: 132 ° C.) is preferable. Of these, propylene glycol monoethyl ether, ethyl lactate, pentyl acetate or cyclohexanone are more preferred, and propylene glycol monoethyl ether or ethyl lactate is particularly preferred.

Among the preferred solvents for the underlayer film are alkoxyalcohol, propylene glycol monoalkyl ether carboxylate, propylene glycol monoalkyl ether, lactic acid ester, acetate ester, alkoxypropionic acid ester, chain ketone, cyclic ketone, lactone, and alkylene. Examples include carbonates.

<Other ingredients>
In addition to the above, the underlayer film forming composition for imprint contains one or more alkylene glycol compounds, polymerization initiators, polymerization inhibitors, antioxidants, leveling agents, thickeners, surfactants and the like. You may.
As the thermal polymerization initiator and the like, each component described in JP-A-2013-036027, JP-A-2014-090133, and JP-A-2013-189537 can be used. Regarding the content and the like, the description in the above publication can be taken into consideration.

<< alkylene glycol compound >>
The underlayer film forming composition for imprint may contain an alkylene glycol compound. The alkylene glycol compound preferably has 3 to 1000 alkylene glycol constituent units, more preferably 4 to 500, still more preferably 5 to 100, and 5 to 100. It is more preferable to have 50 of them. The weight average molecular weight (Mw) of the alkylene glycol compound is preferably 150 to 10000, more preferably 200 to 5000, further preferably 300 to 3000, and even more preferably 300 to 1000.
The alkylene glycol compounds are polyethylene glycol, polypropylene glycol, these mono or dimethyl ethers, mono or dioctyl ethers, mono or dinonyl ethers, mono or didecyl ethers, monostearate esters, monooleic acid esters, monoadiponic acid esters, monosuccinates. Acid esters are exemplified, and polyethylene glycol and polypropylene glycol are preferable.
The surface tension of the alkylene glycol compound at 23 ° C. is preferably 38.0 mN / m or more, and more preferably 40.0 mN / m or more. The upper limit of the surface tension is not particularly specified, but is, for example, 48.0 mN / m or less. By blending such a compound, the wettability of the curable composition for imprint provided directly above the underlayer film can be further improved.
The surface tension is measured at 23 ° C. using a surface tension meter SURFACE TENS-IOMETER CBVP-A3 manufactured by Kyowa Interface Science Co., Ltd. and a glass plate. The unit is mN / m. Two samples are prepared for each level and measured three times each. The arithmetic mean value of a total of 6 times is adopted as the evaluation value.

When the alkylene glycol compound is contained, it is 40% by mass or less, preferably 30% by mass or less, more preferably 20% by mass or less, and preferably 1 to 15% by mass of the non-volatile component. More preferred.
Only one kind of alkylene glycol compound may be used, or two or more kinds may be used. When two or more types are used, the total amount is preferably in the above range.

<< Polymerization Initiator >>
The underlayer film forming composition for imprint may contain a polymerization initiator, and preferably contains at least one of a thermal polymerization initiator and a photopolymerization initiator. By including the polymerization initiator, the reaction of the polymerizable group contained in the underlayer film forming composition for imprinting is promoted, and the adhesion tends to be improved. A photopolymerization initiator is preferable from the viewpoint of improving the cross-linking reactivity with the curable composition for imprinting. As the photopolymerization initiator, a radical polymerization initiator and a cationic polymerization initiator are preferable, and a radical polymerization initiator is more preferable. Further, in the present invention, a plurality of types of photopolymerization initiators may be used in combination.

As the photoradical polymerization initiator, a known compound can be arbitrarily used. For example, halogenated hydrocarbon derivatives (for example, compounds having a triazine skeleton, compounds having an oxadiazole skeleton, compounds having a trihalomethyl group, etc.), acylphosphine compounds such as acylphosphine oxide, hexaarylbiimidazole, oxime derivatives and the like. Oxime compounds, organic peroxides, thio compounds, ketone compounds, aromatic onium salts, ketooxime ethers, aminoacetophenone compounds, hydroxyacetophenones, azo compounds, azide compounds, metallocene compounds, organic boron compounds, iron arene complexes, etc. Can be mentioned. For details thereof, the description in paragraphs 0165 to 0182 of JP-A-2016-0273557 can be referred to, and the contents thereof are incorporated in the present specification.
Examples of the acylphosphine compound include 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide. Further, commercially available products such as IRGACURE-819, IRGACURE1173, and IRGACURE-TPO (trade names: all manufactured by BASF) can be used.

The content of the photopolymerization initiator used in the underlayer film forming composition for imprint is, for example, 0.0001 to 5% by mass, preferably 0.0005 to 3% by mass, among the non-volatile components when blended. %, More preferably 0.01 to 1% by mass. When two or more kinds of photopolymerization initiators are used, the total amount thereof is within the above range.

<Container>
A conventionally known storage container can be used as the storage container for the underlayer film forming composition for imprinting. In addition, as the storage container, for the purpose of suppressing impurities from being mixed into the raw materials and compositions, the inner wall of the container is made of a multi-layer bottle composed of 6 types and 6 layers of resin, and 6 types of resin are formed into a 7-layer structure. It is also preferable to use a bottle of resin. Examples of such a container include the container described in Japanese Patent Application Laid-Open No. 2015-123351.

<Surface free energy>
The surface free energy of the imprint underlayer film formed from the imprint underlayer film forming composition of the present invention is preferably 30 mN / m or more, more preferably 40 mN / m or more, and 50 mN / m or more. Is more preferable. The upper limit is preferably 200 mN / m or more, more preferably 150 mN / m or more, and even more preferably 100 mN / m or more.
The surface free energy can be measured at 23 ° C. using a surface tension meter SURFACE TENS-IOMETER CBVP-A3 manufactured by Kyowa Interface Science Co., Ltd. and a glass plate.

<Curable composition for imprint>
The underlayer film forming composition of the present invention is usually used as a composition for forming an underlayer film of a curable composition for imprinting.
The composition of the curable composition for imprinting is not particularly specified, but preferably contains a polymerizable compound.

Ｌ^２０は、１＋ｑ２価の連結基であり、例えば、１＋ｑ２価の、アルカン構造の基（炭素数１〜１２が好ましく、１〜６がより好ましく、１〜３がさらに好ましい）、アルケン構造の基（炭素数２〜１２が好ましく、２〜６がより好ましく、２〜３がさらに好ましい）、アリール構造の基（炭素数６〜２２が好ましく、６〜１８がより好ましく、６〜１０がさらに好ましい）、ヘテロアリール構造の基（炭素数１〜２２が好ましく、１〜１８がより好ましく、１〜１０がさらに好ましい、ヘテロ原子としては、窒素原子、硫黄原子、酸素原子が挙げられる、５員環、６員環、７員環が好ましい）、またはこれらを組み合わせた基を含む連結基が挙げられる。アリール基を２つ組み合わせた基としてはビフェニルやジフェニルアルカン、ビフェニレン、インデンなどの構造を有する基が挙げられる。ヘテロアリール構造の基とアリール構造の基を組合せたものとしては、インドール、ベンゾイミダゾール、キノキサリン、カルバゾールなどの構造を有する基が挙げられる。
Ｒ^２１およびＲ^２２はそれぞれ独立に水素原子またはメチル基を表す。
Ｌ^２１およびＬ^２２はそれぞれ独立に単結合または上記連結基Ｌを表し、なかでもヘテロ原子を有する連結基が好ましい。Ｌ^２０とＬ^２１またはＬ^２２は連結基Ｌを介してまたは介さずに結合して環を形成していてもよい。Ｌ^２０、Ｌ^２１およびＬ^２２は上記置換基Ｔを有していてもよい。置換基Ｔは複数が結合して環を形成してもよい。置換基Ｔが複数あるとき互いに同じでも異なっていてもよい。
ｑ２は０〜５の整数であり、０〜３の整数が好ましく、０〜２の整数がより好ましく、０または１がさらに好ましい。<< Polymerizable compound >>
The curable composition for imprint preferably contains a polymerizable compound, and it is more preferable that the polymerizable compound constitutes the maximum amount of the component. The polymerizable compound may have one polymerizable group in one molecule or may have two or more polymerizable groups. At least one of the polymerizable compounds contained in the curable composition for imprint preferably contains 2 to 5 polymerizable groups in one molecule, more preferably 2 or 3 polymerizable groups. It is more preferable to include three, and it is more preferable to include three.
At least one of the polymerizable compounds contained in the curable composition for imprint is an aromatic ring (preferably 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, further preferably 6 to 10 carbon atoms) and an alicyclic ring (carbon). The numbers 3 to 24 are preferable, 3 to 18 are more preferable, and 3 to 6 are more preferable), and it is more preferable to contain an aromatic ring. The aromatic ring is preferably a benzene ring.
The molecular weight of the polymerizable compound is preferably 100 to 900.
At least one of the above polymerizable compounds is preferably represented by the following formula (I-1).

L ²⁰ is a 1 + q2 valent linking group, for example, a 1 + q2 valent group having an alcan structure (preferably 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 3 carbon atoms), and an alkene structure group. (Preferably 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, further preferably 2 to 3 carbon atoms), Group having an aryl structure (preferably 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, further preferably 6 to 10 carbon atoms). ), A group having a heteroaryl structure (preferably 1 to 22 carbon atoms, more preferably 1 to 18 carbon atoms, still more preferably 1 to 10 carbon atoms, and examples of the heteroatom include a nitrogen atom, a sulfur atom, and an oxygen atom. , 6-membered ring, 7-membered ring is preferable), or a linking group containing a group combining these. Examples of the group in which two aryl groups are combined include a group having a structure such as biphenyl, diphenylalkane, biphenylene, and indene. Examples of the combination of the heteroaryl structure group and the aryl structure group include groups having a structure such as indole, benzimidazole, quinoxaline, and carbazole.
R ²¹ and R ²² independently represent a hydrogen atom or a methyl group, respectively.
L ²¹ and L ²² each independently represent a single bond or the above-mentioned linking group L, and among them, a linking group having a hetero atom is preferable. L ²⁰ and L ²¹ or L ²² may be combined with or without the linking group L to form a ring. L ²⁰ , L ²¹ and L ²² may have the above-mentioned substituent T. A plurality of substituents T may be bonded to form a ring. When there are a plurality of substituents T, they may be the same or different from each other.
q2 is an integer of 0 to 5, preferably an integer of 0 to 3, more preferably an integer of 0 to 2, and even more preferably 0 or 1.

Examples of the polymerizable compound include the compounds used in the following examples, paragraphs 0017 to 0024 of JP2014-090133A, and the compounds described in Examples, paragraphs 0024 to 0089 of JP2015-009171. Examples of the compound, the compound described in paragraphs 0023 to 0037 of JP2015-070145A, and the compound described in paragraphs 0012 to 0039 of International Publication No. 2016/152597 can be mentioned, but the present invention is limited thereto. It is not interpreted.

The polymerizable compound is preferably contained in the curable composition for imprint in an amount of 30% by mass or more, more preferably 45% by mass or more, further preferably 50% by mass or more, further preferably 55% by mass or more, and further preferably 60% by mass. % Or more, and further 70% by mass or more. Further, the upper limit value is preferably less than 99% by mass, more preferably 98% by mass or less, and may be 97% by mass or less.

It is preferable that the boiling point of the polymerizable compound is set and designed in relation to the specific compound contained in the above-mentioned underlayer film forming composition for imprinting. The boiling point of the polymerizable compound is preferably 500 ° C. or lower, more preferably 450 ° C. or lower, and even more preferably 400 ° C. or lower. The lower limit is preferably 200 ° C. or higher, more preferably 220 ° C. or higher, and even more preferably 240 ° C. or higher.

<< Other ingredients >>
The curable composition for imprint may contain additives other than the polymerizable compound. Other additives may include a polymerization initiator, a surfactant, a sensitizer, a mold release agent, an antioxidant, a polymerization inhibitor and the like.
Specific examples of the curable composition for imprint that can be used in the present invention include the compositions described in JP2013-036027, JP2014-090133, and JP2013-189537. These contents are incorporated herein by reference. Further, the description of the above-mentioned publication can be referred to with respect to the preparation of the curable composition for imprint and the method of forming the film (pattern forming layer), and these contents are incorporated in the present specification.

In the present invention, the content of the solvent in the curable composition for imprint is preferably 5% by mass or less, more preferably 3% by mass or less, and 1% by mass. The following is more preferable.
The curable composition for imprint is a polymer (preferably a polymer having a weight average molecular weight of more than 1,000, more preferably a weight average molecular weight of more than 2,000, still more preferably a weight average molecular weight of 10,000 or more. ) Can be substantially not contained. The term "substantially free of polymer" means, for example, that the content of the polymer is 0.01% by mass or less of the curable composition for imprinting, preferably 0.005% by mass or less, and not contained at all. Is more preferable.

<< Physical characteristics, etc. >>
The viscosity of the curable composition for imprint is preferably 20.0 mPa · s or less, more preferably 15.0 mPa · s or less, further preferably 11.0 mPa · s or less, 9 It is more preferably 0.0 mPa · s or less. The lower limit of the viscosity is not particularly limited, but can be, for example, 5.0 mPa · s or more. Viscosity is measured according to the method below.
The viscosity is measured by adjusting the temperature of the sample cup to 23 ° C. using an E-type rotational viscometer RE85L manufactured by Toki Sangyo Co., Ltd. and a standard cone rotor (1 ° 34'x R24). The unit is mPa · s. Other details regarding the measurement are in accordance with JISZ8803: 2011. Two samples are prepared for each level and measured three times each. The arithmetic mean value of a total of 6 times is adopted as the evaluation value.

The surface tension (γResist) of the curable composition for imprint is preferably 28.0 mN / m or more, more preferably 30.0 mN / m or more, and may be 32.0 mN / m or more. .. By using the curable composition for imprint having a high surface tension, the capillary force is increased, and the curable composition for imprint can be filled into the mold pattern at high speed. The upper limit of the surface tension is not particularly limited, but is preferably 40.0 mN / m or less, preferably 38.0 mN / m, from the viewpoint of imparting the relationship with the underlying film and inkjet suitability. It is more preferably 36.0 mN / m or less, and may be 36.0 mN / m or less. The surface tension of the curable composition for imprinting is measured according to the following method.

The Onishi parameter of the curable composition for imprint is preferably 5.0 or less, more preferably 4.0 or less, and further preferably 3.7 or less. The lower limit of the Onishi parameter of the curable composition for imprint is not particularly specified, but may be, for example, 1.0 or more, and further may be 2.0 or more.
The Onishi parameter can be obtained by substituting the numbers of carbon atoms, hydrogen atoms and oxygen atoms of all the constituents into the following formulas for the non-volatile components of the curable composition for imprint.
Onishi parameter = sum of the number of carbon atoms, hydrogen atoms and oxygen atoms / (number of carbon atoms-number of oxygen atoms)

<< Storage container >>
As a container for the curable composition for imprint used in the present invention, a conventionally known container can be used. In addition, as the storage container, for the purpose of suppressing impurities from being mixed into the raw materials and compositions, the inner wall of the container is made of a multi-layer bottle composed of 6 types and 6 layers of resin, and 6 types of resin are formed into a 7-layer structure. It is also preferable to use a bottle of resin. Examples of such a container include the container described in Japanese Patent Application Laid-Open No. 2015-123351.

<Pattern and pattern formation method>
A method for forming a pattern according to a preferred embodiment of the present invention includes a step of forming a lower layer film on a substrate surface using the lower layer film forming composition for imprinting of the present invention (lower layer film forming step), and a step of forming the lower layer film on the lower layer film (lower layer film forming step). Preferably, a step of applying the underlayer film forming composition for imprinting (the surface of the underlayering film) to form a curable composition layer for imprinting (step of forming a curable composition layer for imprinting), for the above-mentioned imprinting A step of bringing the mold into contact with the curable composition layer, a step of exposing the curable composition layer for imprint in contact with the mold, and a step of exposing the mold to the curable composition layer for imprint. Including the step of peeling from.
Hereinafter, a pattern forming method (a method for producing a cured product pattern) will be described with reference to FIG. It goes without saying that the configuration of the present invention is not limited by the drawings.

<< Underlayer film forming process >>
In the lower layer film forming step, as shown in FIGS. 1 (1) and 1 (2), the lower layer film 2 is formed on the surface of the substrate 1. The underlayer film is preferably formed by applying the underlayer film forming composition for imprinting on the substrate in a layered manner. The substrate 1 may have an undercoat layer or an adhesive film as well as a single layer.

The method of applying the underlayer film forming composition for imprinting to the surface of the substrate is not particularly specified, and a generally well-known application method can be adopted. Specifically, as the application method, for example, a dip coating method, an air knife coating method, a curtain coating method, a wire bar coating method, a gravure coating method, an extrusion coating method, a spin coating method, a slit scan method, or an inkjet method. Is exemplified, and the spin coating method is preferable.
Further, after applying the imprinting underlayer film forming composition on the substrate in a layered manner, the solvent is preferably volatilized (dried) by heat to form a thin underlayer film.

The thickness of the underlayer film 2 is preferably 2 nm or more, more preferably 3 nm or more, further preferably 4 nm or more, 5 nm or more, or 7 nm or more. It may be 10 nm or more. The thickness of the underlayer film is preferably 40 nm or less, more preferably 30 nm or less, further preferably 20 nm or less, and may be 15 nm or less. By setting the film thickness to the above lower limit value or more, the expandability (wetting property) of the curable composition for imprinting on the lower film is improved, and a uniform residual film can be formed after imprinting. By setting the film thickness to the above upper limit value or less, the residual film after imprinting becomes thin, the film thickness unevenness is less likely to occur, and the uniformity of the residual film tends to be improved.

The material of the substrate is not particularly specified, and the description in paragraph 0103 of JP-A-2010-109092 can be referred to, and these contents are incorporated in the present specification. In the present invention, a silicon substrate, a glass substrate, a quartz substrate, a sapphire substrate, a silicon carbide (silicon carbide) substrate, a gallium nitride substrate, an aluminum substrate, an amorphous aluminum oxide substrate, a polycrystalline aluminum oxide substrate, SOC (spin-on carbon), SOG ( Spin-on glass), silicon nitride, silicon oxynitride, and substrates composed of GaAsP, GaP, AlGaAs, InGaN, GaN, AlGaN, ZnSe, AlGa, InP, or ZnO. Specific examples of the material of the glass substrate include aluminosilicate glass, aluminoborosilicate glass, and bariumborosilicate glass. In the present invention, a silicon substrate and a substrate coated with SOC (spin-on carbon) are preferable.

In the present invention, it is preferable to use a substrate having an organic layer as the outermost layer.
Examples of the organic layer of the substrate include an amorphous carbon film formed by CVD (Chemical Vapor Deposition) and a spin-on carbon film formed by dissolving a high carbon material in an organic solvent and performing spin coating. Examples of the spin-on carbon film include nortricyclene copolymer, hydrogenated naphthol novolac resin, naphthol dicyclopentadiene copolymer, phenoldicyclopentadiene copolymer, fluorenbisphenol novolac described in JP-A-2005-128509, and JP-A. Asenaftylene copolymer, inden copolymer described in Japanese Patent Application Laid-Open No. 2005-250434, fullerene having a phenol group, bisphenol compound and its novolac resin, dibisphenol compound and this novolak resin, adamantanphenol described in JP-A-2006-227391. Examples thereof include a novolak resin, a hydroxyvinylnaphthalene copolymer, a bisnaphthol compound described in JP-A-2007-199653, and a resin compound shown in the novolak resin, ROMP, and tricyclopentadiene copolymer.
As an example of SOC, the description in paragraph 0126 of JP2011-164345A can be referred to, the contents of which are incorporated herein by reference.

The contact angle of water on the surface of the substrate is preferably 20 ° or more, more preferably 40 ° or more, and further preferably 60 ° or more. It is practical that the upper limit is 90 ° or less. The contact angle is measured according to the method described in the examples described below.

In the present invention, it is preferable to use a substrate having a basic layer as the outermost layer (hereinafter, referred to as a basic substrate). Examples of the basic substrate include a substrate containing a basic organic compound (for example, an amine compound, an ammonium compound, etc.) and an inorganic substrate containing a nitrogen atom.

<< Imprint curable composition layer forming step >>
In the application step, for example, as shown in FIG. 1 (3), the imprintable curable composition 3 is applied to the surface of the underlayer film 2.
The method of applying the curable composition for imprint is not particularly specified, and paragraph 0102 of JP-A-2010-109092 (the publication number of the corresponding US application is the publication number of US Patent Application Publication No. 2011/0183127). This description is incorporated herein by reference. The curable composition for imprinting is preferably applied to the surface of the underlayer film by an inkjet method. Further, the curable composition for imprint may be applied by multiple coating. In a method of arranging droplets on the surface of the lower layer film by an inkjet method or the like, the amount of the droplets is preferably about 1 to 20 pL, and it is preferable to arrange the droplets on the surface of the lower layer film at intervals. The droplet interval is preferably 10 to 1000 μm. In the case of the inkjet method, the droplet interval is the arrangement interval of the inkjet nozzles.
Further, the volume ratio of the lower layer film 2 to the film-like curable composition for imprint 3 applied on the lower layer film is preferably 1: 1 to 500, and more preferably 1: 10 to 300. It is preferably 1:50 to 200, and more preferably 1:50 to 200.
Further, the method for producing a laminate according to a preferred embodiment of the present invention is a method for producing a laminate using the kit of the present invention, in which the surface of the underlayer film formed from the above-mentioned underlayer film forming composition for imprinting is used. Includes applying a curable composition for imprinting. Further, the method for producing a laminate according to a preferred embodiment of the present invention includes a step of applying the imprint underlayer film forming composition on a substrate in a layered manner, and the imprinting underlayer film forming composition applied in the layered manner. It is preferable to include heating (baking) the product at preferably 100 to 300 ° C., more preferably 130 to 260 ° C., still more preferably 150 to 230 ° C. The heating time is preferably 30 seconds to 5 minutes.

<< Mold contact process >>
In the mold contact step, for example, as shown in FIG. 1 (4), the imprintable curable composition 3 and the mold 4 having a pattern for transferring the pattern shape are brought into contact with each other. By going through such a step, a desired cured product pattern (imprint pattern) can be obtained.
Specifically, the mold 4 is pressed against the surface of the film-like curable composition for imprint 3 in order to transfer a desired pattern to the film-like curable composition for imprint.

The mold may be a light-transmitting mold or a light-impermeable mold. When a light-transmitting mold is used, it is preferable to irradiate the curable composition 3 with light from the mold side. In the present invention, it is more preferable to use a light-transmitting mold and irradiate light from the mold side.
The mold that can be used in the present invention is a mold having a pattern to be transferred. The pattern possessed by the mold can be formed according to a desired processing accuracy by, for example, photolithography or an electron beam drawing method, but the mold pattern manufacturing method is not particularly limited in the present invention. Further, the pattern formed by the cured product pattern manufacturing method according to the preferred embodiment of the present invention can also be used as a mold.
The material constituting the light-transmitting mold used in the present invention is not particularly limited, but is limited to glass, quartz, polymethylmethacrylate (PMMA), light-transmitting resin such as polycarbonate resin, transparent metal vapor-deposited film, polydimethylsiloxane, and the like. A flexible film, a photocurable film, a metal film and the like are exemplified, and quartz is preferable.
The non-light-transmitting mold material used when the light-transmitting substrate is used in the present invention is not particularly limited, but may be any material having a predetermined strength. Specific examples include ceramic materials, vapor-deposited 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. It is not particularly restricted.

In the method for producing a cured product pattern, the mold pressure is preferably 10 atm or less when performing imprint lithography using the curable composition for imprinting. By setting the mold pressure to 10 atm or less, the mold and the substrate are less likely to be deformed, and the pattern accuracy tends to be improved. It is also preferable because the pressurization is low and the device tends to be reduced in size. The mold pressure is preferably selected from a range in which the uniformity of mold transfer can be ensured while the residual film of the curable composition for imprint corresponding to the convex portion of the mold is reduced.
It is also preferable that the contact between the curable composition for imprint and the mold is performed in an atmosphere containing helium gas or condensable gas, or both helium gas and condensable gas.

<< Light irradiation process >>
In the light irradiation step, the curable composition for imprint is irradiated with light to form a cured product. The irradiation amount of light irradiation in the light irradiation step may be sufficiently larger than the minimum irradiation amount required for curing. The irradiation amount required for curing is appropriately determined by examining the consumption amount of unsaturated bonds of the curable composition for imprinting.
The type of light to be irradiated is not particularly specified, but ultraviolet light is exemplified.
Further, in the imprint lithography applied to the present invention, the substrate temperature at the time of light irradiation is usually room temperature, but light irradiation may be performed while heating in order to enhance the reactivity. If a vacuum state is created as a pre-stage of light irradiation, it is effective in preventing air bubbles from being mixed in, suppressing a decrease in reactivity due to oxygen mixing, and improving the adhesion between the mold and the curable composition for imprinting. You may irradiate with light. Further, in the above-mentioned method for producing a cured product pattern, the preferable degree of vacuum at the time of light irradiation is in ^{the range of 10 -1} Pa to normal pressure.
In photoexposure, the light intensity is preferably in the range of 1 to 500 mW / cm ^2, and more preferably in the range of 10~400mW / cm ^2. The exposure time is not particularly limited, but is preferably 0.01 to 10 seconds, more preferably 0.5 to 1 second. Exposure amount is preferably in a range of 5~1000mJ / cm ^2, and more preferably in the range of 10 to 500 mJ / cm ^2.
In the above-mentioned method for producing a cured product pattern, a film-like curable composition for imprinting (pattern forming layer) is cured by light irradiation, and then, if necessary, heat is applied to the cured pattern to further cure it. It may include steps. The temperature for heat-curing the imprint curable composition after light irradiation is preferably 150 to 280 ° C, more preferably 200 to 250 ° C. The time for applying heat is preferably 5 to 60 minutes, more preferably 15 to 45 minutes.

<< Molding process >>
In the mold release step, the cured product and the mold are separated from each other (FIG. 1 (5)). The obtained cured product pattern can be used for various purposes as described later.
That is, the present invention discloses a laminate having a cured product pattern formed from the curable composition for imprinting on the surface of the underlayer film. The film thickness of the pattern forming layer made of the curable composition for imprint used in the present invention varies depending on the intended use, but is about 0.01 μm to 30 μm.
Further, as will be described later, etching or the like can also be performed.

<Cured product pattern and its application>
As described above, the cured product pattern formed by the above-mentioned cured product pattern manufacturing method is used as a permanent film used in a liquid crystal display (LCD) or the like, or as an etching resist (lithography mask) for manufacturing a semiconductor element. Can be done. In particular, the present specification discloses a method for manufacturing a semiconductor device (circuit board), which includes a step of obtaining a cured product pattern by the method for producing a cured product pattern according to a preferred embodiment of the present invention. Further, in the method for manufacturing a semiconductor device according to a preferred embodiment of the present invention, a step of etching or ion-implanting a substrate using the cured product pattern obtained by the above-mentioned method for producing a cured product pattern as a mask and forming an electronic member are formed. It may have a process and. The semiconductor device is preferably a semiconductor element. That is, this specification discloses a method for manufacturing a semiconductor device including the above pattern forming method. Further, the present specification discloses a manufacturing method of an electronic device having a step of obtaining a semiconductor device by the manufacturing method of the semiconductor device and a step of connecting the semiconductor device and a control mechanism for controlling the semiconductor device. ..
Further, a grid pattern is formed on the glass substrate of the liquid crystal display device by using the pattern formed by the above-mentioned cured product pattern manufacturing method, and there is little reflection or absorption, and polarized light having a large screen size (for example, 55 inches or more than 60 inches). It is possible to manufacture the plate at low cost. For example, the polarizing plates described in JP-A-2015-132825 and International Publication No. 2011/132649 can be manufactured.
As shown in FIGS. 1 (6) and 1 (7), the cured product pattern formed in the present invention is also useful as an etching resist (mask for lithography). When the cured product pattern is used as an etching resist, first, a fine cured product pattern on the order of nano or micron is formed on the substrate by the above-mentioned cured product pattern manufacturing method. The present invention is particularly advantageous in that a nano-order fine pattern can be formed, and a pattern having a size of 50 nm or less, particularly 30 nm or less can be formed. The lower limit of the size of the cured product pattern formed by the above-mentioned cured product pattern manufacturing method is not particularly specified, but can be, for example, 1 nm or more.
Further, in the present invention, a step of obtaining a cured product pattern on a substrate by the method for producing a cured product pattern according to a preferred embodiment of the present invention, and a step of etching the substrate using the obtained cured product pattern. Also disclosed is a method for manufacturing an imprint mold having the above.
A desired cured product pattern can be formed on the substrate by etching with an etching gas such as hydrogen fluoride in the case of wet etching and CF _{4 in the case of dry etching.} The cured product pattern has particularly good etching resistance to dry etching. That is, the pattern formed by the cured product pattern manufacturing method is preferably used as a mask for lithography.

Specifically, the pattern formed in the present invention includes a recording medium such as a magnetic disk, a light receiving element such as a solid-state imaging element, a light emitting element such as an LED (light emitting diode) or an organic EL (organic electroluminescence), and a liquid crystal display. Optical devices such as liquid crystals (LCDs), diffraction grids, relief holograms, optical waveguides, optical filters, optical components such as microlens arrays, thin film transistors, organic transistors, color filters, antireflection films, polarizing plates, polarizing elements, optical films, Flat panel display members such as pillars, nanobiodevices, immunoanalytical chips, deoxyribonucleic acid (DNA) separation chips, microreactors, photonic liquid crystals, and fine pattern formation (directed self-assembury) using self-assembly of block copolymers, It can be preferably used for producing a guide pattern or the like for DSA).

Hereinafter, the present invention will be described in more detail with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

<Synthesis of A-1 / B-1 (90/10) copolymer>
Water; 100 g as a solvent was placed in a flask, and the temperature was raised to 90 ° C. under a nitrogen atmosphere. In the water, glycidyl methacrylate; 16.0 g (0.16 mol) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), disodium disodium phosphate 2-acryloyloxyethyl below; 1.8 g (7 mmol) (Fujifilm Wako Pure Chemical Industries, Ltd.) Yakuhin), 2,2'-azobis (2- (2-imidazolin-2-yl) propane dihydrochloride) (VA-044); 1.0 g (3 mmol) (Fujifilm Wako Pure Chemical Industries, Ltd.), water 50 g of the mixed solution was added dropwise over 2 hours. After completion of the dropping, the copolymer was further stirred at 90 ° C. for 4 hours to obtain a copolymer.
Acrylic acid; 11.6 g (0.16 mol) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), tetraethylammonium bromide (TEAB); 2.1 g (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 4-hydroxy- Tetramethylpiperidin 1-oxyl (4-HO-TEMPO); 50 mg (manufactured by Wako Pure Chemical Industries, Ltd.) was added and reacted at 90 ° C. for 8 hours, and it was confirmed from H-NMR that the acrylic acid disappeared by the reaction. , An aqueous solution of resin was obtained. The reaction scheme is shown below.
1N Hydrochloric acid was added to the above aqueous solution, and the precipitated product was purified by washing with water to obtain a powder of resin A-1 / B-1.
Other copolymers were synthesized in the same manner.

リン酸二ナトリウム２−アクリロイルオキシエチル（分子量２５４．２）

Disodium Phosphate 2-Acryloyloxyethyl (Molecular Weight 254.2)

The above resin was dissolved in PGMEA to obtain a PGMEA solution.
The weight average molecular weight (Mw, polystyrene equivalent) determined from gel permeation chromatography (GPC) of the obtained resin was 20,000, and the dispersity (Mw / Mn) was 2.2.
<Measurement method of molecular weight>
The weight average molecular weight (Mw) of the resin was defined as a polystyrene-equivalent value according to gel permeation chromatography (GPC measurement). The apparatus used was HLC-8220 (manufactured by Tosoh Corporation), and guard columns HZ-L, TSKgel Super HZM-M, TSKgel Super HZ4000, TSKgel Super HZ3000 and TSKgel Super HZ2000 (manufactured by Tosoh Co., Ltd.) were used as columns. .. The eluate used was THF (tetrahydrofuran). An RI detector was used for detection.

<Preparation of underlayer film forming composition>
A solution containing the components shown in the table below was prepared. This was filtered through a 0.02 μm nylon filter and a 0.010 μm PTFE (polytetrafluoroethylene) filter to prepare the preparation of the underlayer film forming composition shown in Examples and Comparative Examples.

<Preparation of curable composition for imprint>
The various compounds listed in the table below are mixed, and 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl-free radical (manufactured by Tokyo Kasei Co., Ltd.) is added as a polymerization inhibitor in the total amount of the polymerizable compounds. It was prepared by adding the amount to 200% by mass (0.02% by mass). This was filtered through a 0.02 μm nylon filter and a 0.001 μm PTFE filter to prepare a curable composition for imprinting.

<Calculation of pKa>
It was calculated using the following software package.
Software Package: Advanced Chemistry Development (ACD / Labs) Software V8.14 for Solaris (1994-2007 ACD / Labs)

<Formation of underlayer film / film thickness evaluation>
The underlayer film forming composition for imprint described in the table was spin-coated on the substrate shown in the table below, and heated using a hot plate under the baking conditions described in the table to form the underlayer film. The film thickness of the underlayer film was measured by an ellipsometer.

<Evaluation of adhesion>
On the surface of the underlayer film obtained above, a curable composition for imprint whose temperature was adjusted to 23 ° C. was ejected at a droplet amount of 6 pL per nozzle using an inkjet printer DMP-2831 manufactured by Fujifilm Dimatics. Then, the droplets were applied onto the underlayer film so as to form a square arrangement at intervals of about 100 μm to form a pattern forming layer. Next, a quartz wafer spin-coated with the composition for forming an adhesion layer shown in Example 6 of JP2014-024322A was pressed against the pattern forming layer in a He atmosphere (replacement rate of 90% or more) and imprinted. The curable composition for use was imprinted. When 10 seconds had passed after the stamping, exposure was performed from the mold side using a high-pressure mercury lamp under ^{the condition of 150 mJ / cm 2.} The force required to peel off the exposed sample was measured and used as the adhesion force F of the underlayer film.
A: F ≧ 30N
B: 25N ≤ F <30N
C: 20N ≤ F <25N
D: F <20N

<Surface (evaluation of peeling defects)>
On the surface of the underlayer film obtained above, a curable composition for imprint whose temperature was adjusted to 25 ° C. was ejected at a droplet amount of 6 pL per nozzle using an inkjet printer DMP-2831 manufactured by Fujifilm Dimatics. Then, the droplets were applied onto the underlayer film so as to form a square arrangement at intervals of about 100 μm to form a pattern forming layer. Next, a quartz mold (a line pattern having a line width of 28 nm and a depth of 60 nm) was pressed against the pattern forming layer under a He atmosphere (replacement rate of 90% or more), and the curable composition for imprint was filled in the mold. When 10 seconds had passed after the imprint, the mold was exposed from the mold side using a high-pressure mercury lamp under ^{the condition of 150 mJ / cm 2} , and then the mold was peeled off to transfer the pattern to the pattern forming layer. The presence or absence of peeling of the transferred pattern was confirmed by optical microscope observation (macro observation) and SEM observation (micro observation).
A: No pattern peeling was confirmed B: No peeling was confirmed by macro observation, but pattern peeling was confirmed by micro observation C: Partial area (demolding end) by macro observation ) Was confirmed to be peeled off. D: Peeling was confirmed over the front of the transfer area by macro observation.

In Tables 5 and 6 below, A-1 / B-1 of the polymer means that it is a copolymer having a structural unit of A-1 and a structural unit of B-1. 90/10 represents the copolymerization ratio (molar ratio), and means the ratio of the left structural unit and the right structural unit, respectively. As the pKa of the monomer, the pKa value of the monomer having a pKa of 4.0 or less among the monomers constituting the polymer was adopted. The meanings of the abbreviations in the table are as follows.
PGMEA: Propylene glycol monomethyl ether acetate PGME: Propylene glycol monomethyl ether γBL: γ-butyrolactone Mw: Weight average molecular weight

<Board>
Substrate Si: Silicon wafer with a diameter of 8 inches (1 inch is 2.54 cm) Substrate 1: Spin-on carbon film ODL-102 (manufactured by Shin-Etsu Chemical Co., Ltd.) is spun-coated on a silicon wafer with a diameter of 8 inches. A substrate formed by coating and baking at 240 ° C. for 60 seconds to form a SOC (Spin on Carbon) film having a film thickness of 200 nm.
Substrate 2: A spin-on carbon film ODL-50 (manufactured by Shin-Etsu Chemical Co., Ltd.) is applied on a silicon nitride wafer having a diameter of 8 inches by a spin coating method, baked at 240 ° C. for 60 seconds, and SOC (Spin on) having a film thickness of 200 nm is applied. Carbon) A substrate on which a film is formed.
Substrate 3: SOC NCA9053EH (manufactured by Nissan Chemical Industries, Ltd.) was applied on a silicon wafer having a diameter of 8 inches by a spin coating method, and baked at 240 ° C. for 60 seconds to form an SOC (Spin on Carbon) film having a film thickness of 200 nm. substrate.
Substrate SOG: A substrate obtained by applying OCD T-12 (manufactured by Tokyo Ohka Kogyo Co., Ltd.) on a silicon wafer having a diameter of 8 inches by a spin coating method and subjecting it to UV ozone treatment for 120 seconds to form an SOG film having a film thickness of 200 nm.

As is clear from the above results, when a lower layer film is formed in the lower layer film forming composition for imprint using a polymer having a structural unit derived from a monomer having a pKa of 4.0 or less and a polymerizable group, a curable composition for imprinting is formed. It was possible to realize the excellent adhesion of (Examples 1 to 15). In particular, these imprint underlayer film forming compositions have realized good adhesion on various substrates such as substrates having different carbon contents and SOG substrates, and it has been found that they are highly versatile materials. It was. Further, in the samples of all the examples, the imprint layer formed on the surface of the underlayer film had a good surface shape.
On the other hand, when the above-mentioned specific polymer was not used (Comparative Example 1), the adhesion was inferior.

1 Substrate 2 Underlayer film 3 Imprint curable composition 4 Mold

Claims (22)

An imprint underlayer film forming composition containing a polymer and a solvent, wherein the polymer contains a structural unit derived from a monomer having a pKa of 4.0 or less and a polymerizable group. The underlayer film forming composition for imprint according to claim 1, wherein the polymer is an acrylic resin. The underlayer film forming composition for imprint according to claim 1 or 2, wherein the polymer has a weight average molecular weight of 2,000 or more. The underlayer film forming composition for imprint according to any one of claims 1 to 3, wherein the polymerizable group of the polymer is a (meth) acryloyl group. The underlayer film formation for imprint according to any one of claims 1 to 4, wherein the structural unit derived from a monomer having a pKa of 4.0 or less contained in the polymer is a structural unit derived from a monomer having a pKa of 3.0 or less. Composition. The structural unit derived from the monomer having a pKa of 4.0 or less consists of a group consisting of a hydroxyl group, a carboxyl group, a thiocarboxylic acid group, a dithiocarboxylic acid group, a sulfonic acid group, a phosphoric acid monoester group, a phosphoric acid diester group and a phosphoric acid group. The underlayer film forming composition for imprint according to any one of claims 1 to 5, which has at least one selected. The imprint underlayer film forming composition according to any one of claims 1 to 6, wherein 99.0% by mass or more of the imprint underlayer film forming composition is a solvent. The underlayer film forming composition for imprint according to any one of claims 1 to 7, wherein the polymer has a structural unit having a polymerizable group. A kit comprising the underlayer film forming composition for imprinting and the curable composition for imprinting according to any one of claims 1 to 8. A curable composition for imprinting used in the kit according to claim 9. An imprint film formed from the substrate, the underlayer film forming composition for imprint according to any one of claims 1 to 8 located on the surface of the substrate, and an imprint film located on the surface of the underlayer film. A laminate having an imprint layer formed from a curable composition. The laminate according to claim 11, wherein a substrate having an organic layer as the outermost layer is used as the substrate. The laminate according to claim 11 or 12, wherein a substrate having a basic layer as the outermost layer is used as the substrate. A step of applying the imprint underlayer film forming composition according to any one of claims 1 to 8 to the surface of a substrate to form an imprint underlayer film, a curable composition for imprinting on the surface of the underlayer film. A method for producing a laminate, which comprises a step of applying an object. The method for producing a laminate according to claim 14, wherein a substrate having an organic layer as the outermost layer is used as the substrate. The method for producing a laminate according to claim 14 or 15, wherein a substrate having a basic layer as the outermost layer is used as the substrate. A step of forming a lower layer film on the surface of a substrate using the lower layer film forming composition for imprint according to any one of claims 1 to 8, applying the lower layer film forming composition for imprinting on the lower layer film. The step of forming the curable composition layer for imprint, the step of bringing the mold into contact with the curable composition layer for imprint, and exposing the curable composition layer for imprint in the state where the mold is in contact. A pattern forming method, which comprises a step of peeling the mold from the exposed curable composition layer for imprinting. The pattern forming method according to claim 17, wherein a substrate having an organic layer as the outermost layer is used as the substrate. The pattern forming method according to claim 17 or 18, wherein a substrate having a basic layer as the outermost layer is used as the substrate. The pattern forming method according to any one of claims 17 to 19, wherein the underlayer film forming composition for imprint is applied to a substrate surface by a spin coating method. The pattern forming method according to any one of claims 17 to 20, wherein the curable composition for imprint is applied onto an underlayer film by an inkjet method. A method for manufacturing a semiconductor device, which comprises the pattern forming method according to any one of claims 17 to 21.

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