JP5305091B2 - Photosensitive resin composition for optical nanoimprint lithography Resin composition, pattern forming method using the same, fine structure, and photocured product removal method - Google Patents

Description

The present invention relates to a photosensitive resin composition for optical nanoimprint lithography for forming a fine pattern, a pattern forming method using the same, a fine structure, and a photocured product removing method.

2. Description of the Related Art In recent years, semiconductor integrated circuits have been miniaturized and integrated, and photolithography apparatuses have been improved in accuracy as a pattern transfer technique for realizing the fine processing. But,
The processing accuracy has approached the wavelength of the light source for light exposure, and the lithography technology has also approached its limit. Therefore, in order to advance further miniaturization and higher accuracy, an electron beam drawing apparatus, which is a kind of charged particle beam apparatus, has been used in place of lithography technology.

Unlike the batch exposure method in pattern formation using a light source such as i-line or excimer laser, pattern formation using an electron beam takes a method of drawing a mask pattern. The exposure (drawing) takes time and the pattern formation takes time. Therefore, the memory capacity is 256 mega, 1 giga, 4 giga,
As the degree of integration increases dramatically, the density of the pattern increases, and the pattern formation time increases correspondingly, and there is a concern that the throughput is significantly inferior. Therefore, in order to increase the speed of the electron beam drawing apparatus, development of a collective figure irradiation method in which various shapes of masks are combined and irradiated with an electron beam collectively to form an electron beam with a complicated shape is underway. . As a result, while miniaturization of the pattern has been promoted, there has been a drawback that the electron beam drawing apparatus needs to be enlarged and complicated, and the apparatus cost is increased.

On the other hand, technologies for performing fine pattern formation at low cost are disclosed in Patent Documents 1 and 2 below.
Non-Patent Document 1 and the like. In this method, a predetermined pattern is transferred by embossing a mold (mold) having the same pattern as the pattern to be formed on the substrate against the resin film layer formed on the surface of the substrate to be transferred. is there. In particular, according to the nanoimprint technology described in Patent Document 2 and Non-Patent Document 1, a silicon wafer is used as a mold, and a fine structure of 25 nanometers or less can be formed by transfer.

Nanoimprint technology is roughly divided into two types depending on the material to be transferred. One is a thermal nanoimprint technique in which a material to be transferred is heated, plastically deformed by a mold, and then cooled to form a pattern. The other is a photo-nanoimprint that forms a pattern by applying a light-curing resin that is liquid at room temperature on a substrate, then pressing a light-transmitting mold against the resin and irradiating it with light. Technology. In particular, optical nanoimprint technology enables pattern formation at room temperature, so that distortion due to differences in the linear expansion coefficient between the substrate and mold due to heat is unlikely to occur, and high-precision pattern formation is possible. Have been bathed. Non-Patent Document 2 introduces PAK-01 (manufactured by Toyo Gosei Co., Ltd.) as a photocurable resin used in the optical nanoimprint technology.

The process when the optical nanoimprint technique is used for fine processing of a substrate is as follows. The flow is shown in FIG.
(A) The photosensitive resin composition film 2 is formed on the substrate 1 by a spin coating method or an ink jet method.
(B) The mold 3 having a fine pattern formed on the surface is pressed against the surface of the photosensitive resin composition film 2. Thereby, the photosensitive resin composition film | membrane 2 is patterned in the shape of a mold.
(C) The photosensitive resin composition is cured by irradiating ultraviolet rays from the upper part of the mold 3. In this case, the mold 3 is transparent. As a transparent mold material, quartz or the like is usually used. Also,
When the substrate 1 is transparent, ultraviolet rays may be irradiated from the substrate side.
(D) The mold 3 is peeled off from the cured photosensitive resin composition film 2 (5).
(E) When forming a pattern, the layer (base layer) 4 which is not patterned normally remains.
The base layer 4 is removed by etching such as ion irradiation, and a resist pattern 6 is formed.
(F) The substrate 1 is processed by etching or the like using the resist pattern 6 as a mask.
(G) The resist pattern 6 is removed.

Through the above process, a fine pattern can be formed on the substrate surface using the optical nanoprint technique.

In the optical nanoimprint technology, a mold having a fine processing corresponding to a target pattern is required. In general, since a mold is processed by drawing a pattern with an electron beam, the processing time increases dramatically as the number of patterns becomes finer, and the throughput is significantly inferior. Therefore, the cost of the mold becomes very high.

From such circumstances, regeneration of the mold is required in the optical nanoimprint technology,
The releasability from the mold of the photocured resin composition (photocured product) is a problem. It is difficult to remove a photocured product composed of a highly crosslinked polymer once attached to a mold with a general organic solvent, acid, alkali or the like. There is also a method of removing by heating at a high temperature, but there is a possibility that the mold is deformed or damaged.

So far, the cured product can be obtained by a method using a mold made of hydrogenated silsesquioxane or a fluorinated ethylene propylene copolymer having excellent releasability, or a surface treatment of the mold with a fluorinated alkylene oxide or the like. Attempts have been made to resolve the adhesion. However, there is a problem that the surface treatment of the mold is peeled off by repeatedly performing nanoimprinting, and there is a demand for a method that can remove the photocured product under mild conditions and regenerate the mold.

In recent years, various studies have been made on constituent materials of decomposable photosensitive resin compositions for nanoimprinting. For example, a photocrosslinking polymer that can be resolubilized by heating and a composition for forming the same have been proposed. Non-Patent Document 3 discloses a method of removing a cured product containing a diacrylate having an acetal structure in an acidic solvent, a method of heating a polymer having a structure wound with a Diels-Alder reaction to 130 ° C., and a urethane. A method for decomposing a polymer having a structure by heating to 150 ° C. is disclosed.

Non-Patent Document 4 discloses a method of replicating a mold using a photosensitive composition. A photosensitive composition obtained by adding a photo radical initiator and a photo acid generator to a diacrylate containing a hemiacetal structure as a decomposable group is cured with light having a wavelength of 365 nm, and then a wavelength of 265 nm.
When an acid is generated by this light, the hemiacetal structure is decomposed, and the photocured product can be dissolved in methanol.

US Pat. No. 5,259,926 US Pat. No. 5,772,905

S. Y. Chou et al. Appl. Phys. Lett. vol. 67, p. 3314 (1995) Y. Kurashima, Jpn. J. et al. Appl. Phys. vol. 42. p. 3871 (2003) W. H. Heath et al. Macromolecules. vol. 41, p. 719 (2008) Daisaku Matsukawa, two others, Polymer Preprints, Japan Vol. 57, p. 5383 (2008)

However, the methods disclosed in Non-Patent Documents 3 and 4 require an acidic solvent, an acid generator, or heating in order to remove the photocured product. When removing photocured material by thermal decomposition,
There was a problem that the mold was deformed or damaged by heating. In addition, when photocured material is removed by cutting the cross-linked polymer bond with an acid generator, the material cannot be applied to a cationic polymerization resin composition, or cannot be used for applications that hate acid impurities and corrosion. There was a problem that the usage was limited.

For example, Non-Patent Document 4 uses a photosensitive resin composition containing a photoacid generator that generates acid by light and heating. In this case, the replicated resin mold is also heated at the same time and is further in contact with an acid, which may cause deformation and corrosion of the resin mold. If solubilization is performed only with light at a low temperature such as room temperature, a strong acid must be generated.

The present invention has been made in view of the actual situation as described above, and is a photosensitive resin composition for photo-nanoimprint lithography that is excellent in removability of a photocured product, a resist pattern forming method using the same, and a microstructure. And it aims at providing the removal method of photocured material.

The present invention provides [1] (A) two or more polymerizable groups and a characteristic group containing a bond that is cleaved when irradiated with a second actinic ray having a wavelength shorter than that of the first actinic ray. There is provided a photosensitive resin composition for optical nanoimprint lithography, comprising a photopolymerizable compound contained therein and (B) a photopolymerization initiator that generates active species when irradiated with a first actinic ray.

In the present invention, [2] the characteristic group containing a bond that is cleaved when irradiated with a second actinic ray having a shorter wavelength than the first actinic ray of the photopolymerizable compound (A) is represented by the following formula: (1) to formula (4)
The photosensitive resin composition for optical nanoimprint lithography according to the above [1], which is a group represented by any one of:

[3] The photosensitive resin composition for optical nanoimprint lithography according to [1] or [2], wherein the polymerizable group of the photopolymerizable compound (A) is an ethylenically unsaturated bond. I will provide a.

The present invention also provides [4] the above [3], wherein the polymerizable group of the photopolymerizable compound (A) is any one of acrylate, methacrylate, vinyl ether, allyl ether, or styrene.
The photosensitive resin composition for optical nanoimprint lithography as described in 1. is provided.

The present invention also provides [5] the photosensitive resin composition for optical nanoimprint lithography according to [1] or [2] above, wherein the polymerizable group of the photopolymerizable compound (A) is epoxy or oxetane. To do.

Moreover, this invention is [6] Any of said [1]-[4] in which the said (A) photopolymerizable compound contains the compound represented by either of the following general formula (5)-(8). A photosensitive resin composition for photo-nanoimprint lithography as described above is provided.

［一般式（５）〜（８）中、Ｘ^１、Ｘ^２、Ｘ^３、Ｘ^４及び、Ｙ^１、Ｙ^２、Ｙ^３、Ｙ^４は、
それぞれ独立にメチレン基、エチレン基又はプロピレン基を示し、Ｒ^１、Ｒ^２、Ｒ^３、及
びＲ^４は、それぞれ独立に２価の有機基を示し、Ｒは水素原子又はメチル基を示し、ｍ_１
＋ｎ_１、ｍ_２＋ｎ_２、ｍ_３＋ｎ_３、ｍ_４＋ｎ_４は、それぞれ０〜２０の整数である。］

[In General Formulas (5) to (8), X ¹ , X ² , X ³ , X ⁴ and Y ¹ , Y ² , Y ³ , Y ⁴ are
Each independently represents a methylene group, ethylene group or propylene group; R ¹ , R ² , R ³ and R ⁴ each independently represents a divalent organic group; R represents a hydrogen atom or a methyl group; ₁
+ N ₁ , m ₂ + n ₂ , m ₃ + n ₃ , and m ₄ + n ₄ are each an integer of 0 to 20. ]

[7] The present invention provides [7] wherein the viscosity at 25 ° C. is 20 mPa · s or less.
The photosensitive resin composition for optical nanoimprint lithography as described in any one of-[6] is provided.

Furthermore, the present invention provides [8] The optical nanoimprint lithography according to any one of the above [1] to [7], further comprising a photopolymerizable compound having in the molecule thereof at least one polymerizable group and a cyclic structure. A photosensitive resin composition is provided.
In the present invention, [9] the photopolymerizable compound having at least one polymerizable group and a cyclic structure in the molecule contains a compound having one (meth) acryloyl group and a cyclic structure in the molecule. The photosensitive resin composition for optical nanoimprint lithography as described in said [8] is provided.
The present invention also includes a step of forming a resin film made of the photosensitive resin composition according to any one of [1] to [9] on a [10] substrate;
A step of pressing a mold having a fine concavo-convex pattern on the surface to the surface of the resin film, and transferring the concavo-convex pattern of the mold to the resin film;
Irradiating a first actinic ray to cure the resin film and forming a cured film on the substrate;
Peeling the mold from the cured film surface;
And removing a base layer formed between the convex part of the mold of the cured film and the substrate by etching to form a cured pattern on the substrate.

Moreover, this invention provides the pattern formation method as described in said [10] which further includes the process of [11] etching the said board | substrate using the said hardening pattern as a mask, and the process of removing the said hardening pattern.
[12] The present invention also provides a microstructure having a fine pattern formed by the pattern forming method described in [12] above [10] or [11].
The present invention also provides [13] above-mentioned [10] cured by irradiating a first actinic ray.
Or a photocured product obtained by irradiating the photocured product obtained by the pattern forming method according to [11] with a second actinic ray having a wavelength shorter than that of the first actinic ray. A method for removing objects is provided.

According to the present invention, a photosensitive resin composition for optical nanoimprint lithography capable of removing a photocured product without generation of heat or acid, and a pattern forming method using the same,
A method for removing the fine structure and the photocured product can be provided.

It is a schematic diagram explaining the process of optical nanoimprint lithography method.

Hereinafter, preferred embodiments of the present invention will be described in detail. In the present invention, (meth) acrylate means acrylate or a corresponding methacrylate, and (meth) acryloyl group means an acryloyl group or a corresponding methacryloyl group.

(Photosensitive resin composition for optical nanoimprint lithography)
As described above, the photosensitive resin composition for optical nanoimprint lithography of the present invention includes the following components (A) and (B).
(A) A photopolymerizable compound having in its molecule two or more polymerizable groups and a characteristic group containing a bond that is cleaved when irradiated with a second actinic ray having a wavelength shorter than that of the first actinic ray ,
(B) A photopolymerization initiator that generates active species when irradiated with the first actinic ray is contained.

(A) A photopolymerizable compound having in its molecule two or more polymerizable groups and a characteristic group containing a bond that is cleaved when irradiated with a second actinic ray having a wavelength shorter than that of the first actinic ray Will be described.
(A) The photopolymerizable compound is a compound having the above-described configuration, and when the compound is irradiated with a second actinic ray having a wavelength shorter than that of the first actinic ray, the bond in the characteristic group is cleaved. The
Here, the characteristic group containing a bond that is cleaved by irradiating the photoactive compound (A) with the second actinic ray is represented by the above formula (1), (2), (3) or (4). From the viewpoint of curability of the photosensitive resin composition, a group represented by the above general formula (1), (2) or (3) is more preferable.

In addition, the polymerizable group in the (A) photopolymerizable compound is preferably an ethylenically unsaturated bond, more preferably any one of (meth) acrylate, vinyl ether, allyl ether, and styrene. From the viewpoint of curability of the resin composition, (meth) acrylate is more preferable.

Furthermore, (A) the photopolymerizable compound preferably contains a compound represented by the above general formula (5), (6), (7) or (8), and a curable viewpoint of the photosensitive resin composition. Therefore, it is more preferable to contain the compound represented by the general formula (5), (6) or (7).

In the general formula (5), X ¹ and Y ¹ each independently represent a methylene group, an ethylene group or a propylene group, and are preferably a methylene group or an ethylene group. R ¹ and R ² are
Each independently represents a divalent organic group, and R represents a hydrogen atom or a methyl group. m ₁ + n ₁ is
It is an integer of 0 to 20, preferably 0 to 10, and more preferably 0 to 5.

Examples of the divalent organic group include a linear or branched alkylene group, an arylene group,
Examples thereof include divalent groups including an ether bond, a sulfide bond, a disulfide bond, a carbonyl group, an ester bond, an amino group, an amide bond, and a urethane bond. The hydrogen atom of the linear or branched alkylene group may be substituted with an arbitrary substituent to such an extent that the effects of the present invention are not impaired.

In the general formula (6), X ² and Y ² each independently represent a methylene group, an ethylene group or a propylene group, and are preferably a methylene group or an ethylene group. R represents a hydrogen atom or a methyl group. m < ₂ > + n < ₂ > is an integer of 0-20, it is preferable that it is 0-10, and it is more preferable that it is 0-5.

In the general formula (7), X ³ and Y ³ each independently represent a methylene group, an ethylene group or a propylene group, and are preferably a methylene group or an ethylene group. R ³ and R ⁴ are
Each independently represents a divalent organic group, and R represents a hydrogen atom or a methyl group. m ₃ + n ₃ is
It is an integer of 0 to 20, preferably 0 to 10, and more preferably 0 to 5.

In the general formula (8), X ⁴ and Y ⁴ each independently represent a methylene group, an ethylene group or a propylene group, and are preferably a methylene group or an ethylene group. R represents a hydrogen atom or a methyl group, and m ₄ + n ₄ is an integer of 0 to 20, preferably 0 to 10, and more preferably 0 to 5.

In addition, the photopolymerizable compound (A) needs to have a wavelength of the second actinic ray at which the bond in the above characteristic group is cleaved shorter than that of the first actinic ray, but is 300 nm or less. Preferably, it is 200-300 nm. In the case where the bond is cleaved with an actinic ray having a wavelength longer than that of the first actinic ray, the cleaving occurs unintentionally when the photosensitive resin composition is cured.

Examples of the synthesis of the photopolymerizable compound (A) having a characteristic group having the structure represented by the above formula (1) (general formula (5)) include one or more per molecule after dimerization of maleic anhydride. And a method of reacting a compound having one hydroxyl group with one amino group.
Examples of the compound having one or more hydroxyl groups and one amino group in one molecule include 2-aminoethanol, p-aminophenol, amino-2-methoxymethylphenol, 2- (
2-aminoethoxy) ethanol, 4-amino-3-fluorophenol, 4-amino-3-hydroxymethylphenol, 4-amino-2-methylphenol, 4-amino-2-hydroxymethylphenol, 4-amino-2 -Methoxymethylphenol, 4-amino-2-aminomethylphenol, 4-amino-2- (β-hydroxyethylaminomethyl) phenol, 4-amino-2-fluorophenol, and the like.

As the photopolymerizable compound (A) having a characteristic group having the structure represented by the above formula (2) (general formula (6)), a compound synthesized by dimerizing a commercially available coumarin derivative such as 6-hydroxycoumarin is used. be able to.

Examples of the method for synthesizing the photopolymerizable compound (A) having the characteristic group having the structure represented by the above formula (3) (general formula (7)) include a method of reacting alcohol after dimerization of maleic anhydride. It is done.

Examples of the alcohol include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and the like.

The photopolymerizable compound (A) having a characteristic group having the structure represented by the above formula (4) (general formula (8)) is synthesized by dimerizing a commercially available anthracene derivative such as 9-anthracenylmethyl methacrylate. Can be used.

In the photosensitive resin composition of the present invention, these (A) photopolymerizable compounds may be used alone or in combination.
More than one species can be used in combination.
(A) Light having two or more polymerizable groups of the present invention and a characteristic group containing a bond that is cleaved when irradiated with a second active light having a shorter wavelength than the first active light in the molecule The polymerizable compound is
It is preferable to contain 5-50 mass% with respect to the solid content mass of the whole photosensitive resin composition,
More preferably, the content is 45% by mass, and more preferably 15-40% by mass. If this content is less than 5% by mass, the removability tends to decrease, and if it exceeds 50% by mass, the viscosity tends to increase.

In addition to the photopolymerizable compound (A), the photosensitive resin composition of the present invention is not limited to (A ′) other polymer having at least one polymerizable group in the molecule as long as the effects of the present invention are not impaired. You may contain a photopolymerizable compound. Examples of other photopolymerizable compounds include (meth) acrylate compounds, epoxy compounds, oxetane compounds, vinyl ether compounds, styrene compounds, and the like.

Examples of the (meth) acrylate compound include phenoxy glycol (meth) acrylate, phenoxyethylene glycol (meth) acrylate, 2-phenoxyethyl (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, behenyl (meth) acrylate, benzyl (meth) acrylate, 1-adamantyl (meth) acrylate, isobornyl (meth) acrylate , Tridecyl (meth) acrylate, lauryl (meth) acrylate, octoxypolyethylene glycol (meth) acrylate, 2-
Hydroxy-3-phenoxypropyl (meth) acrylate, isostearyl (meth) acrylate, lauryl (meth) acrylate, polyethylene glycol di (meth) acrylate,
Ethoxylated bisphenol A di (meth) acrylate, propoxylated bisphenol A di (
(Meth) acrylate, 1,10-decanediol di (meth) acrylate, cyclodecane dimethanol di (meth) acrylate, ethoxylated-2-methyl-1,3-propanediol di (meth) acrylate, diethylene glycol di (meth) Acrylate, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 2,2,3
, 3,4,4,5,5-octafluoro-1,6-hexyl di (meth) acrylate, 2-
Hydroxy-3-acryloxypropyl (meth) acrylate, ethylene di (meth) acrylate, propoxylated ethoxylated bisphenol A di (meth) acrylate, 1,6-
Hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth)
Acrylate, polypropylene glycol di (meth) acrylate, ethylene glycol di
(Meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, tricyclo [5.2.1.02,6] decane dimethanol ( (Meth) acrylate, ethoxylated isocyanuric acid tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) ) Acrylate, ethoxylated pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, propoxylated pentaerythritol tetra (
(Meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, dicyclopentenyl (meth) acrylate, 1,4-cyclohexanedimethanol di (meth) acrylate 1,4-benzenedimethanol di (meth) acrylate, hydrogenated bisphenol A di (meth) acrylate, 1,3-adamantanediol di (meth) acrylate, and the like, but are not limited thereto. These may be used alone or in combination of two or more.

Examples of the epoxy compound include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, brominated bisphenol A diglycidyl ether, brominated bisphenol F diglycidyl ether, brominated bisphenol S diglycidyl ether, water Bisphenol A diglycidyl ether, hydrogenated bisphenol F diglycidyl ether, hydrogenated bisphenol S diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin triglycidyl ether, trimethylol Examples include, but are not limited to, propane triglycidyl ether, polyethylene glycol diglycidyl ether, and the like. These may be used alone or in combination of two or more.

Examples of the oxetane compound include 3-ethyl-3-hydroxymethyloxetane, 3- (meth) allyloxymethyl-3-ethyloxetane, (3-ethyl-3-oxetanylmethoxy) methylbenzene, 4-fluoro- [1- (3-Ethyl-3-oxetanylmethoxy) methyl]
Benzene, 4-methoxy- [1- (3-ethyl-3-oxetanylmethoxy) methyl] benzene, [1- (3-ethyl-3-oxetanylmethoxy) ethyl] phenyl ether, isobutoxymethyl (3-ethyl-3 -Oxetanylmethyl) ether, isobornyloxyethyl (
Examples include, but are not limited to, 3-ethyl-3-oxetanylmethyl) ether, isobornyl (3-ethyl-3-oxetanylmethyl) ether, and the like. These may be used alone or in combination of two or more.

Examples of the vinyl ether compound include n-propyl vinyl ether, n-butyl vinyl ether, n-hexyl vinyl ether, t-butyl vinyl ether, t-amyl vinyl ether, cyclohexyl vinyl ether, aryl vinyl ether, dodecyl vinyl ether, ethylene glycol butyl vinyl ether, ethylhexyl vinyl ether, isobutyl vinyl ether. , Polyethylene glycol methyl vinyl ether, triethylene glycol methyl vinyl ether, triethylene glycol divinyl ether, butanediol divinyl ether, cyclohexane dimethanol divinyl ether, diethylene glycol divinyl ether, hexanediol divinyl ether, tetraethylene glycol divinyl ether, 1,4-buta Diol divinyl ether, tricyclodecane dimethanol divinyl ether, trimethylolpropane trivinyl ether, and the like, but are not limited thereto. These may be used alone or in combination of two or more.

Examples of the styrene compound include styrene, p-methylstyrene, p-methoxystyrene,
β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene, p-methoxy-
Examples include, but are not limited to, β-methylstyrene and p-hydroxystyrene.
These may be used alone or in combination of two or more.

In addition, the number of polymerizable groups of the photopolymerizable compound can in principle be four or more functional groups,
As the size of the molecule increases, the viscosity increases, which is disadvantageous for the formation of a fine structure of several nanometers. Therefore, it is preferable to use a monomer having two or less functional groups.

The photosensitive resin composition of the present invention preferably further contains a photopolymerizable compound having at least one polymerizable group and a cyclic structure in the molecule from the viewpoint of improving etching resistance. And a compound having a cyclic structure in the molecule is more preferable. As the cyclic structure, either an aliphatic ring or an aromatic ring can be used. As the aliphatic ring, a cycloalkyl group having 4 to 12 carbon atoms and a hydrogen atom thereof substituted with an arbitrary substituent. In addition, examples of the aromatic ring include a phenyl group, a naphthyl group, a furanyl group, a pyrrole group, and the like, and those in which these hydrogen atoms are substituted with an arbitrary substituent.

The polymerizable group is preferably an ethylenically unsaturated bond, more preferably (meth) acrylate, vinyl ether, allyl ether or styrene, from the viewpoint of curability of the photosensitive resin composition. More preferably, it is (meth) acrylate.
When the photosensitive resin composition contains a photopolymerizable compound having one polymerizable group and a cyclic structure in the molecule, the content improves the viscosity, curability and etching resistance of the photosensitive resin composition in a balanced manner. From the viewpoint of, it is preferably 5 to 60% by mass, more preferably 10 to 60% by mass, and further preferably 15 to 60% by mass based on the solid content mass of the entire photosensitive resin composition. preferable.
Further, when the photosensitive resin composition contains a photopolymerizable compound having two or more polymerizable groups and a cyclic structure in the molecule, the content is determined by the viscosity, curability and etching resistance of the photosensitive resin composition. From the viewpoint of improving the balance in a balanced manner, it is 5 to 50 with respect to the solid mass of the entire photosensitive resin composition.
It is preferable that it is mass%, It is more preferable that it is 10-45 mass%, 15-40
More preferably, it is mass%.

  Next, (B) the photopolymerization initiator will be described.

The photopolymerization initiator (B) used in the present invention that generates active species when irradiated with the first actinic ray is a photoradical polymerization initiator and / or photoacid having an appropriate activity corresponding to the reaction system and wavelength. A generator is used. These can be applied alone, but can also be used in combination of two or more. In addition, it can also be applied in combination with known photopolymerization accelerators and sensitizers. The blending ratio of the photopolymerization initiator used in the present invention is 0.1 to 15% by mass, preferably 0.3 to 10% by mass, based on the entire photosensitive resin composition.
More preferably, it is 5-5 mass%.

As radical photopolymerization initiators, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propane-1 -One, benzophenone, 1- [4- (2-hydroxyethoxy) -phenyl
] -2-Hydroxy-2-methyl-1-propan-1-one, 2-methyl-1- [4- (methylthio)
Phenyl] -2-morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1- (
4-morpholinophenyl) -butanone-1, bis (2,6-dimethoxybenzoyl) -2,4
4-trimethyl-pentylphosphine oxide, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (η5-2, 4-Cyclopentadiene-1-yl) -bis (2,6-difluoro-
3- (1H-pyrrol-1-yl) -phenyl) titanium, 2- (dimethylamino) -2-[(4
-Methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone and the like. Among them, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one is preferable because of its high curing rate.

Examples of the photoacid generator include diazonium salts, iodonium salts, bromonium salts, chloronium salts, sulfonium salts, selenonium salts, pyrylium salts, thiapyrylium salts, pyridinium salts and other onium salts; tris (trihalomethyl) -s-triazine and Halogenated compounds such as derivatives thereof; 2-nitrobenzyl ester of sulfonic acid; iminosulfonate; 1-oxo-2-diazonaphthoquinone-4-sulfonate derivative; N-hydroxyimidosulfonate; tri (methanesulfonyloxy) benzene derivative Bissulfonyldiazomethanes; sulfonylcarbonylalkanes; sulfonylcarbonyldiazomethanes; disulfone compounds and the like.

In the present invention, the entire photosensitive resin composition needs to be liquid at normal temperature (15 to 30 ° C.). In particular, by using a solvent-free composition, shrinkage and deformation during pattern formation can be prevented, and a highly accurate pattern can be formed. Accordingly, it is preferable that the oligomer as well as the monomer are liquid at room temperature.

The photosensitive resin composition according to the present invention may contain a reactive diluent. The following can be applied as the reactive diluent used. N-vinylpyrrolidone, acryloylmorpholine, N, N-dimethylacrylamide, N-methylolacrylamide, N
, N-dimethylaminopropylacrylamide and the like. These can be used alone or in combination.

The photosensitive resin composition of the present invention has a viscosity at 25 ° C. of 20 mPa · s or less, preferably 3 to 15 mPa · s, and more preferably 8 to 13 mPa · s. preferable. By setting such a viscosity, it is possible to impart the ability to form a fine concavo-convex pattern before curing, coating suitability and other processing suitability, and after curing, in terms of resolution, residual film properties, substrate adhesion or other points Excellent film properties can be imparted. When the viscosity of the photosensitive resin composition exceeds 20 mPa · s, the followability to the concavo-convex pattern is deteriorated, and a longer time or stronger pressure is required until the mold is filled.

The photosensitive resin composition according to the present invention may contain a fluorine-based surfactant. As the fluorosurfactant, a perfluoroalkyl-containing oligomer and a perfluoroalkyl-containing oligomer solution dissolved in a solvent can be used. In addition, as the fluorosurfactant, those having a hydrocarbon chain bonded to a perfluoroalkyl chain may be used. In addition, as the fluorosurfactant, one having a structure in which an ethoxy chain or a methoxy chain is bonded to a perfluoroalkyl chain can be used. Further, as the fluorosurfactant, those having a structure in which siloxane is bonded to these perfluoroalkyl chains can also be used. A commercially available fluorine surfactant can also be used as the fluorine surfactant. The addition amount is preferably within the range of 0.01% by mass to 1% by mass of the whole.

Hereinafter, a pattern forming method and a pattern transfer method using the photosensitive resin composition for optical nanoimprint lithography of the present invention will be described.

The photosensitive resin composition for optical nanoimprint lithography of the present invention can be formed by coating by a generally well-known coating method, for example, a dip coating method, a spin coating method, an ink jet method, a slit scanning method, or the like.

The mold used in the present invention has a fine pattern to be transferred,
The method for forming the pattern on the mold (stamper) is not particularly limited. For example, it is selected according to desired processing accuracy such as photolithography or electron beam drawing. The material of the mold (mold) may be any material having strength and required workability such as silicon wafer, various metal materials, glass, quartz, ceramic, and plastic. Specifically, S
Preferred examples include i, SiC, SiN, polycrystalline Si, Ni, Cr, Cu, and those containing one or more of these. In particular, quartz is preferable because it is highly transparent and light is efficiently irradiated to the resin during photocuring. When an opaque material is used, light is irradiated from the surface opposite to the mold to cure the resin.

Moreover, it is more preferable that the mold surface is subjected to a mold release treatment for preventing adhesion with the resin. As a surface treatment method, it is preferable that a fluorine compound is formed on the surface with a thickness of several nanometers in addition to a silicone release agent.

In the present invention, the material to be the substrate is not particularly limited, but any material having a predetermined strength may be used. Specifically, silicon, various metal materials, glass, ceramic, plastic,
In the case where the mold (mold) is opaque, a transparent substrate can be used.

Although it does not restrict | limit especially as light which hardens the photosensitive resin composition of this invention, The light or radiation of the wavelength of area | regions, such as near ultraviolet, far ultraviolet, visible, and infrared, is mentioned. Examples of the ultraviolet ray source include an ultraviolet fluorescent lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a xenon lamp, a carbon arc lamp, and a solar lamp. Examples of radiation include microwaves and EUV (Extreme Ultra Viol).
et, extreme ultraviolet). These lights may be light having a plurality of different wavelengths, but the wavelength of the second active light having a characteristic group is shorter than the first active light having a wavelength at which the polymerization initiator generates active species. It is necessary to select an appropriate light.

The method for removing a photocured product of the present invention can be applied to a use in which it is necessary to remove the photosensitive resin composition after it has been cured without any particular limitation. And according to the removal method of this photocured material, since the photosensitive resin composition of the present invention having the above-described effects is used, the removal is performed after irradiation with the second actinic ray or while irradiation. It can be removed easily and reliably.

Reversible photodimerization has been known over the last few decades. [2 + 2] cycloaddition and photocleavage of the corresponding cyclobutane derivative, and [4 + 4] cycloaddition and the corresponding reverse reaction. Usually, the dimerization proceeds at longer wavelengths around 300-400 nm and photocleavage is 254n.
This is done at shorter wavelengths near m. Reversible photodimerization has been reported for maleimide derivatives, coumarin derivatives, cinnamates, stilbenes, and the like and is well known.

In the [2 + 2] photoreaction, both the photodimerization reaction and radical polymerization may proceed.
The radical polymerization is considered to be initiated by radicals generated from ethylenically unsaturated bonds excited by light irradiation by extracting hydrogen from a hydrogen donor and generating ethyl radicals on the ethylenically unsaturated bonds.

In the case of the photopolymerizable compound (A) of the present invention, a structure in which a ring is wound by a [2 + 2] reaction is included in the molecule in advance, and there is no possibility that radical polymerization proceeds.

With such a photosensitive resin composition, it is possible to form a photocured product having high sensitivity and a high degree of curing and capable of forming a fine structure by nanoimprinting, and excellent resolution can be obtained.
And about the removability of the formed photocured material, since the above-mentioned photopolymerizable compound is used, the photocured material can be decomposed by irradiating light of a predetermined wavelength, and the photocured material can be removed. Is possible.

Hereinafter, the present invention will be described based on examples, but the present invention is not limited thereto. Unless otherwise indicated, “part” and “%” used below are based on mass.

[(A) Synthesis of photopolymerizable compound]
<(A) Synthesis of Photopolymerizable Compound A-1>
By irradiating maleic anhydride with a high-pressure xenon lamp in carbon tetrachloride for 1 hour,
1,2,3,4-Cyclobutanetetracarboxy dianhydride was obtained. Add aminophenol to a DMF (dimethylformaldehyde) solution of 1,2,3,4-cyclobutanetetracarboxy dianhydride, stir for 3 hours, add acrylic chloride, and stir for another 1 hour to obtain photopolymerizable compound A-1. Obtained. In addition, when the structure was analyzed by measuring the NMR spectrum of this compound, it was confirmed that it had two acryloyl groups in one molecule, and it was confirmed that it was a compound represented by the following formula (9) It was done.

<Synthesis of (A) Photopolymerizable Compound A-2>
To a DMF solution of 1,2,3,4-cyclobutanetetracarboxy dianhydride, add 2- (2-aminoethoxy) ethanol, stir for 3 hours, add acrylic chloride and stir for an additional hour, and then photopolymerizable compound A-2 was obtained. As a result of measuring the NMR spectrum of this compound and analyzing the structure, it was confirmed that it had two acryloyl groups in one molecule, and it was confirmed that it was a compound represented by the following formula (10). It was done.

<Synthesis of (A) Photopolymerizable Compound A-3>
To a DMF solution of 1,2,3,4-cyclobutanetetracarboxy dianhydride, add 2- (2-aminoethoxy) ethanol, stir for 3 hours, add 2-isocyanatoethyl methacrylate, stir for an additional hour, Polymerizable compound A-3 was obtained. In addition, when the structure was analyzed by measuring the NMR spectrum of this compound, it was confirmed that it had two acryloyl groups in one molecule, and it was confirmed that it was a compound represented by the following formula (11) It was done.

<Synthesis of (A) Photopolymerizable Compound A-4>
Hydroxycoumarin, potassium carbonate, acrylic chloride, and potassium iodide were dissolved in DMF and stirred overnight at 110 ° C. under nitrogen. It cooled to room temperature (25 degreeC) and extracted with ethyl acetate, and photopolymerizable compound A-4 was obtained. In addition, when the structure was analyzed by measuring a NMR spectrum about this compound, it was confirmed that it has two acryloyl groups in 1 molecule, and following formula (1)
It was confirmed that it was a compound represented by 2).

<Synthesis of (A) Photopolymerizable Compound A-5>
Hydroxycoumarin, potassium carbonate, 2-hydroxyethyl vinyl ether and potassium iodide were dissolved in DMF and stirred overnight at 110 ° C. under nitrogen. The mixture was cooled to room temperature and extracted with ethyl acetate to obtain a photopolymerizable compound A-5. As a result of measuring the NMR spectrum of this compound and analyzing its structure, it was confirmed that it had two vinyl ether groups in one molecule, and it was confirmed that it was a compound represented by the following formula (13). It was done.

<Synthesis of (A) Photopolymerizable Compound A-6>
Hydroxycoumarin, potassium carbonate, 2-bromoethanol, potassium iodide in DMF
And stirred at 110 ° C. overnight under nitrogen. The mixture was cooled to room temperature, extracted with ethyl acetate, purified by flash chromatography, and then reacted with acrylic chloride in DMF to produce photopolymerizable compound A.
-6 was obtained. In addition, when the structure was analyzed by measuring the NMR spectrum of this compound, it was confirmed that it had two acryloyl groups in one molecule, and it was a compound represented by the following general formula (14). confirmed.

<Synthesis of (A) Photopolymerizable Compound A-7>
Add 2-hydroxyethyl acrylate and 4-methoxyphenol to a THF solution of 1,2,3,4-cyclobutanetetracarboxy dianhydride and stir overnight at 65 ° C. under nitrogen to obtain photopolymerizable compound A-7. It was. In addition, when the structure was analyzed by measuring the NMR spectrum of this compound, it was confirmed that it had two acryloyl groups in one molecule, and it was a compound represented by the following general formula (15). confirmed.

<(A) Synthesis of Photopolymerizable Compound A-8>
To a THF solution of 1,2,3,4-cyclobutanetetracarboxy dianhydride, add 2-hydroxyethyl vinyl ether and 4-methoxyphenol, and stir overnight at 65 ° C. under nitrogen.
Photopolymerizable compound A-8 was obtained. In addition, when the structure was analyzed by measuring the NMR spectrum of this compound, it was confirmed that it had two vinyl ether groups in one molecule, and it was a compound represented by the following general formula (16). confirmed.

<Synthesis of (A) Photopolymerizable Compound A-9>
By irradiating 9-antolol in carbon tetrachloride with a high-pressure xenon lamp for 1 hour,
A dimer was obtained. The obtained dimer was dissolved in DMF, 2-hydroxyethyl acrylate and 4-methoxyphenol were added, and the mixture was stirred under nitrogen for 5 days to obtain a photopolymerizable compound A-9.
In addition, when the structure was analyzed by measuring the NMR spectrum of this compound, it was confirmed that it had two acryloyl groups in one molecule, and it was a compound represented by the following general formula (17). confirmed.

<Synthesis of (A) Photopolymerizable Compound A-10>
By irradiating 9-antolol in carbon tetrachloride with a high-pressure xenon lamp for 1 hour,
A dimer was obtained. The obtained dimer was dissolved in DMF, 2-hydroxyethyl vinyl ether and 4-methoxyphenol were added, and the mixture was stirred for 5 days under nitrogen to obtain photopolymerizable compound A-10. In addition, when the structure was analyzed by measuring the NMR spectrum of this compound, it was confirmed that it had two vinyl ether groups in one molecule, and it was a compound represented by the following general formula (18). confirmed.

(Examples 1-12 and Comparative Example 1)
(A) Photopolymerizable compounds A-1 to A- synthesized as described above as photopolymerizable compounds
10 and A′-1: tetraethylene glycol dimethacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 4G) were prepared for comparison.
And (A) Photopolymerizable compounds other than the photopolymerizable compound shown in Table 1, (B) Photopolymerization initiator (photoradical polymerization initiator, photoacid generator), and additives are used according to the following preparation method. Fabricate a photosensitive resin composition for photo-nanoimprint lithography, kinematic viscosity, curability, etching resistance,
The cured product removability was evaluated, and the results are summarized in Table 1.

The (meth) acrylate compound which is a photopolymerizable compound other than the photopolymerizable compound (A) used in Examples and Comparative Examples of the present invention is as follows.
A′-2: 2-phenoxyethyl acrylate (manufactured by SARTOMER)
A′-3: Isobornyl acrylate (manufactured by SARTOMER)
A′-4: Lauryl acrylate (manufactured by SARTOMER)
A′-5: Neopentyl glycol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.)

The vinyl ether compound which is a photopolymerizable compound other than the photopolymerizable compound (A) used in Examples and Comparative Examples of the present invention is as follows.
A'-6: Octadecyl vinyl ether (Nippon Carbide Industries Co., Ltd.)
A′-7: Triethylene glycol divinyl ether (manufactured by BASF)

Abbreviations for the photo radical polymerization initiator and photo acid generator used in the examples and comparative examples of the present invention are as follows.
B-1: 2-Methyl-1- [4- (methylthio) phenyl] -2-morpholino-propane-1-
ON (Ciba Specialty Chemicals, trade name: Irgacure I-907)
B-2: Bis [4- (di (4- (2-hydroxyethoxy) phenyl) sulfonio) -phenyl] sulfide bis-hexafluoroantimonate (manufactured by ADEKA Corporation, trade name: SP170)

The abbreviations of the additives used in Examples and Comparative Examples of the present invention are as follows.
C-1: 9-methylanthracene (manufactured by Tokyo Chemical Industry Co., Ltd.)

(Formulation method); The procedure is as follows.
1) Weigh photopolymerization initiator 2) Add photopolymerization initiator to photopolymerizable compound and stir and dissolve 3) Stir for 1 hour with mix rotor 4) Filter with 0.2 μm membrane filter

(Measurement of kinematic viscosity)
Using an E-type viscometer (manufactured by Tokyo Keiki Co., Ltd., VISCONIC ELD), 1.2 mL of the evaluation sample was injected into the sample cup. Next, a sample cup was attached to the main body, and the viscosity was measured by rotating the rotor. All viscosity measurements were made at 25 ° C. The unit is “mPa · s”.

(Curability evaluation)
The surface was previously released with OPTOOL DSX (Daikin Industries, Ltd.) and the diameter was 160 nm.
An evaluation sample is 0.05 μm on a silicon mold having a trench having a depth of 400 nm.
After dropping L, a 15 mm × 15 mm glass substrate was placed on the mold. 500W under reduced pressure
Using an ultra-high pressure mercury lamp, light of 365 nm was irradiated from the glass substrate side by 0.1 J / cm ² . After irradiation (exposure), the mold is peeled off, and AFM (Neescope D5000, manufactured by Veeco)
) Was used to observe the shape of the cured resist present on the substrate surface. And sclerosis | hardenability was evaluated as follows.
“○”: The resist is completely cured, and pillars that are almost the same as the pattern shape of the mold are formed. “△”: Confirm that the resist is not partially cured. “X”: The resist is almost cured. Or the pillars are not formed overall

(Evaluation of etch rate)
After 0.2 μL of an evaluation sample was dropped on a 15 mm × 15 mm glass substrate (manufactured by Nippon Electric Glass Co., Ltd., OA-10), the surface was previously subjected to mold release treatment with Optool DSX (Daikin Industries, Ltd.). A 15 mm x 15 mm glass substrate is placed and 500 W is applied under reduced pressure.
Using an ultra-high pressure mercury lamp, light of 365 nm was irradiated from the glass substrate side at 3 J / cm ² . The glass substrate on which the mold release treatment was performed was peeled to form a resin film, and a part of the resin film was masked with a polyimide adhesive tape to prepare a sample. Next, this sample was introduced into a processing chamber of a dry etcher (manufactured by Shinko Seiki Co., Ltd., RIE etching apparatus with EXAM turbo), and then CHF ₃ gas was treated for 900 s under conditions of a flow rate of 50 mL / min, a pressure of 3 Pa, and an output of 100 W. Remove the masking tape and measure the level difference between the treated and non-treated surfaces (Veeco, Dektak 200V-Si
). Resist OFPR-800 (manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used as a reference. 15 mm × 15 mm glass substrate (manufactured by Nippon Electric Glass Co., Ltd., OA-1
0) After dropping 0.1 g on the top, spin coater (Mikasa Co., Ltd., 1H-DX2) 50
After preliminary rotation at 0 rpm / 10 s, main rotation at 2000 rpm / 30 s and 2500 rpm / 3 s was performed. A 15 mm × 15 mm glass substrate whose surface was previously subjected to release treatment with OPTOOL DSX (manufactured by Daikin Industries, Ltd.) was placed on this, and 36 ° C. using a 500 W ultrahigh pressure mercury lamp in a reduced pressure.
Light of 5nm was irradiated 3J / cm ² from the glass substrate side. The glass substrate on which the mold release treatment was performed was peeled to form a resin film, and etching evaluation was performed in the same manner as the above sample, and the etching rate was calculated by dividing the step of the evaluation sample by the step of OFPR-800, Evaluation was performed as follows.
“◯”: The etching rate is less than 1 “Δ”: The etching rate is 1 or more and less than 1.5 “×”: The etching rate is 1.5 or more

(Evaluation of removal of cured product)
After forming a resist pattern on the substrate surface using the same method as the evaluation of curability, the resist was removed by immersion in methanol at 1000 J / cm ² with 265 nm light using a low-pressure mercury lamp. . Thereafter, the substrate surface was observed using a digital microscope and evaluated as follows.
“◯”: The resist is completely removed from the substrate surface “△”: A part of the resist remains on the substrate surface “×”: The resist pattern is completely left on the substrate surface

(A) the photopolymerizable compound of the present invention and (B) a photopolymerization initiator, (B) the photopolymerization initiator contains a compound that generates active species when irradiated with the first actinic ray, (A) The photopolymerizable compound contains two or more polymerizable groups and a characteristic group containing a bond that is cleaved when irradiated with a second actinic ray having a wavelength shorter than that of the first actinic ray. In the examples containing the compound contained in the above, the viscosity is equivalent to that of the photopolymerizable compound of Comparative Example 1 that is often used conventionally, the formation of the fine structure is easy, and the cured product removability is excellent. In this example, Example 3 using A′-4 which does not have a ring, and when a photoacid generator is used as a polymerization initiator (Examples 7, 10, and 12), curability,
Although slightly inferior in etching resistance, (A) the photopolymerizable compound is particularly excellent in cured product removability by using the above compound.

From the above results, according to the photosensitive resin composition of the present invention, it is possible to improve the removability of the cured product while maintaining the fine structure forming ability.

1... Substrate 2. Photosensitive resin composition film (photo-curable resin)
3 ... Mold 4 ... Base layer 6 ... Resist pattern.

Claims (13)

(A) A photopolymerizable compound having in its molecule two or more polymerizable groups and a characteristic group containing a bond that is cleaved when irradiated with a second actinic ray having a wavelength shorter than that of the first actinic ray And (B) A photosensitive resin composition for optical nanoimprint lithography, containing a photopolymerization initiator that generates active species when irradiated with a first actinic ray. (A) The characteristic group containing the bond cut | disconnected when irradiated with the 2nd actinic ray whose wavelength is shorter than the 1st actinic ray of the photopolymerizable compound of following formula (1)-a formula (4) The photosensitive resin composition for optical nanoimprint lithography according to claim 1, which is a group represented by any one of the above.

The photosensitive resin composition for optical nanoimprint lithography according to claim 1, wherein the polymerizable group of the photopolymerizable compound (A) is an ethylenically unsaturated bond. The photosensitive resin composition for optical nanoimprint lithography according to claim 3, wherein the polymerizable group of the photopolymerizable compound (A) is any one of acrylate, methacrylate, vinyl ether, allyl ether, or styrene. The photosensitive resin composition for optical nanoimprint lithography according to claim 1, wherein the polymerizable group of the photopolymerizable compound (A) is epoxy or oxetane. The photosensitive resin composition for optical nanoimprint lithography according to any one of claims 1 to 4, wherein the (A) photopolymerizable compound contains a compound represented by any one of the following general formulas (5) to (8). object.

[In General Formulas (5) to (8), X ¹ , X ² , X ³ , X ⁴ and Y ¹ , Y ² , Y ³ , Y ⁴ are
Each independently represents a methylene group, ethylene group or propylene group; R ¹ , R ² , R ³ and R ⁴ each independently represents a divalent organic group; R represents a hydrogen atom or a methyl group; ₁
+ N ₁ , m ₂ + n ₂ , m ₃ + n ₃ , and m ₄ + n ₄ are each an integer of 0 to 20. ] The photosensitive resin composition for optical nanoimprint lithography according to claim 1, wherein the viscosity at 25 ° C. is 20 mPa · s or less. Furthermore, the photosensitive resin composition for optical nanoimprint lithography in any one of Claims 1-7 containing the photopolymerizable compound which has at least 1 polymeric group and cyclic structure in a molecule | numerator. The photopolymerizable compound having in the molecule thereof at least one polymerizable group and a cyclic structure is 1
The photosensitive resin composition for optical nanoimprint lithography of Claim 8 containing the compound which has two (meth) acryloyl groups and a cyclic structure in a molecule | numerator. Forming a resin film comprising the photosensitive resin composition according to any one of claims 1 to 9 on a substrate;
A step of pressing a mold having a fine concavo-convex pattern on the surface to the surface of the resin film, and transferring the concavo-convex pattern of the mold to the resin film;
Irradiating a first actinic ray to cure the resin film and forming a cured film on the substrate;
Peeling the mold from the cured film surface;
Removing the base layer formed between the convex part of the mold of the cured film and the substrate by etching, and forming a cured pattern on the substrate;
A pattern forming method. Etching the substrate using the cured pattern as a mask;
Removing the cured pattern;
The pattern formation method according to claim 10, further comprising: A fine structure having a fine pattern formed by the pattern forming method according to claim 10. The photocured material obtained by the pattern forming method according to claim 10 or 11 cured by irradiating with the first actinic ray is irradiated with a second actinic ray having a wavelength shorter than that of the first actinic ray. A method for removing the photocured product, wherein the photocured product is removed.

Images