Resin composition for phase separation structure formation, and method for manufacturing structure including phase separation structure

Abstract

To provide a resin composition for phase separation structure formation which enables formation of a phase separation structure reduced in pattern roughness and pattern errors, and a method for manufacturing a structure including a phase separation structure which uses the same.SOLUTION: A resin composition for phase separation structure formation contains a first block copolymer having a first a block and a first b block, and a second block copolymer having a second a block and a second b block, wherein the first a block and the second a block are each independently constituted of a polymer composed of a repeated structure of a constitutional unit represented by a formula (b1), the second b block is constituted of a polymer composed of a repeated structure of a constitutional unit represented by a formula (b2b), and the number average molecular weight of the second block copolymer is 40,000 or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resin composition for forming a phase separation structure and a method for manufacturing a structure including the phase separation structure.

Background Art

[0002] In recent years, with the further miniaturization of large-scale integrated circuits (LSIs), technologies for processing more delicate structures have been demanded. In response to such demands, technologies for forming finer patterns have been developed by utilizing phase separation structures formed by self-organization of block copolymers in which blocks that are incompatible with each other are bonded (see, for example, Patent Document 1).

[0003] The above block copolymer separates (phase separates) in microscopic regions due to the repulsion between blocks that are incompatible with each other, and by performing heat treatment or the like, a structure having a regular periodic structure is formed. Specific examples of this periodic structure include cylinders (columnar), lamellae (plate-like), spheres (spherical), and the like.

[0004] In order to utilize the phase separation structure of the block copolymer, it is essential to form a self-organized nanostructure formed by microphase separation only in specific regions and arrange it in a desired direction. In order to achieve these position control and orientation control, processes such as graphoepitaxy for controlling the phase separation pattern by a guide pattern and chemical epitaxy for controlling the phase separation pattern by differences in the chemical state of the substrate have been proposed (see, for example, Non-Patent Document 1).

[0005] The block copolymer forms a structure having a regular periodic structure by phase separation. The "period of the structure" means the period of the phase structure observed when a structure of the phase separation structure is formed, and refers to the sum of the lengths of the respective phases that are incompatible with each other. When the phase separation structure forms a cylinder structure perpendicular to the substrate surface, the period (L0) of the structure is the center-to-center distance (pitch) between two adjacent cylinder structures.

[0006] The period (L0) of the structure is known to be determined by the degree of polymerization N and the inherent polymerization characteristics such as the Flory-Huggins interaction parameter χ. That is, the larger the product “χ·N” of χ and N, the greater the mutual repulsion between different blocks in the block copolymer. Therefore, when χ·N > 10.5 (hereinafter referred to as the “strength separation limit point”), the repulsion between different types of blocks in the block copolymer is large, and the tendency of phase separation to occur becomes stronger. And at the strength separation limit point, the period of the structure is approximately N 2 / 3 ·χ 1 / 6 and the relationship of the following formula (1) holds. That is, the period of the structure is proportional to the degree of polymerization N that correlates with the molecular weight and the molecular weight ratio between different blocks.

[0007] L0 ∝ a·N 2 / 3 ·χ 1 / 6 ···(1) [In the formula, L0 represents the period of the structure. a is a parameter indicating the size of the monomer. N represents the degree of polymerization. χ is the interaction parameter, and the larger this value, the higher the phase separation performance.]

[0008] Therefore, by adjusting the composition and total molecular weight of the block copolymer, the period (L0) of the structure can be adjusted. For this reason, in order to form a structure with a smaller L0 using the phase separation structure formed by the self-assembly of the block copolymer, a method of reducing the molecular weight of the block copolymer has been considered. However, simply reducing the molecular weight of the block copolymer may cause a problem that the degree of polymerization (N) decreases and phase separation does not occur. Therefore, a material (High χ material) having a large interaction parameter (χ) is required so that phase separation occurs even when the molecular weight of the block copolymer is reduced. However, since many of such High χ materials have a slow phase separation rate, the conditions for phase separation are limited and they lack practicality.

[0009] As a Highχ material that eliminates such drawbacks, for example, Patent Document 2 proposes a block copolymer having a block of styrene and a block composed of a random copolymer of 2-hydroxy-3-(2,2,2-trifluoroethylsulfanyl)propyl methacrylate and methyl methacrylate, which has a larger χ than a block copolymer having a block of styrene and a block of methyl methacrylate, and it has been shown that phase separation can be achieved under conventional conditions.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0011]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0012] As described above, Patent Document 2 shows that phase separation can be achieved under conventional conditions. However, for the purpose of further improving practicality, it is required to further improve the phase separation speed, reduce FER (Fingerprint Edge Roughness), or enlarge the Grain. When phase separation is caused to occur in a lamellar structure without forming a guide pattern, a phase separation structure with a random fingerprint pattern is obtained, and the roughness index of such a fingerprint pattern is FER. It is known that the roughness during DSA pattern formation can be reduced by using a material that can obtain a phase separation structure with a low FER. Also, when phase separation is caused to occur in a cylinder structure without forming a guide pattern, a pattern in which the cylinder structure is oriented at positions corresponding to a hexagonal closest-packed structure is formed in a plan view, and a region (cluster) where the same orientation pattern continues is a Grain. That is, there is a deviation in the orientation pattern of the cylinder structure between a certain Grain and the Grain adjacent to it. It is known that the error during DSA pattern formation can be reduced by using a material that can obtain a phase separation structure with large Grains.

[0013] The present invention has been made in view of the above circumstances, and an object thereof is to provide a resin composition for forming a phase separation structure capable of forming a phase separation structure with reduced pattern roughness and pattern error, and a method for manufacturing a structure including the phase separation structure using the same.

Means for Solving the Problems

[0014] As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by using a predetermined second block copolymer in addition to a predetermined first block copolymer that is a High χ material, and have completed the present invention. Specifically, the present invention provides the following.

[0015] [1] A resin composition for forming a phase separation structure containing a first block copolymer and a second block copolymer, wherein the first block copolymer has a first a block and a first b block, the second block copolymer has a second a block and a second b block, The first block (1a) and the second block (2a) are each independently composed of a polymer having a repeating structure of a structural unit represented by the following formula (b1). The second block (2b) is composed of a polymer having a repeating structure of a structural unit represented by the following formula (b2b). The number average molecular weight of the second block copolymer in terms of standard polystyrene determined by gel permeation chromatography (GPC) measurement is 40,000 or less. The resin composition for forming a phase separation structure, wherein the first block copolymer satisfies any one of the following (1) or (2). (1) The first block (1b) is composed of a random copolymer having a structure in which a structural unit represented by the following formula (b2a) and a structural unit represented by the following formula (b2b) are randomly arranged. (2) In the first block (1a), n in the following formula (b1) is an integer of 1 or more and 5 or less. The first block (1b) is composed of a polymer having a repeating structure of a structural unit represented by the following formula (b2b). [Chemical formula] (In formula (b1), R b1 is a hydrogen atom or a methyl group, R 1 is an alkyl group which may have an oxygen atom or a silicon atom, n is an integer of 0 or more and 5 or less, and when n is an integer of 2 or more, a plurality of R 1 may be the same or different from each other. In formula (b2a), X is a sulfur atom or an oxygen atom, R 3 is an alkylene group which may have a hydroxy group, R 2 is a hydrogen atom or a monovalent organic group. In formula (b2a) and formula (b2b), R b2 is each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and a plurality of R b2 may be the same or different from each other.)

[0016] [2] In formula (b2a), R 2 is a hydrogen atom, an acyl group, a thioacyl group, an alkenyl group, or an alkyl group which may have a silyl group, a fluorine atom, a carboxy group, an amino group, a hydroxy group or a phosphate group, The resin composition for forming a phase separation structure according to [1].

[0017] [3] The ratio of the mass of the first block copolymer to the total of the mass of the first block copolymer and the mass of the second block copolymer is 30% by mass or more and 95% by mass or less, The resin composition for forming a phase separation structure according to [1] or [2].

[0018] [4] The ratio of the number of moles of the constitutional unit of the first block a to the total of the number of moles of the constitutional unit of the first block a and the number of moles of the constitutional unit of the first block b is 20 mol% or more and 80 mol% or less, The ratio of the number of moles of the constitutional unit of the second block a to the total of the number of moles of the constitutional unit of the second block a and the number of moles of the constitutional unit of the second block b is 20 mol% or more and 80 mol% or less, The resin composition for forming a phase separation structure according to any one of [1] to [3].

[0019] [5] When the first block copolymer satisfies the above (1), in the first block b, the ratio of the number of moles of the constitutional unit represented by the formula (b2a) to the total of the number of moles of the constitutional unit represented by the formula (b2a) and the number of moles of the constitutional unit represented by the formula (b2b) is 0.90 or less, The resin composition for forming a phase separation structure according to any one of [1] to [4].

[0020] [6] Coating the resin composition for forming a phase separation structure according to any one of [1] to [5] on a support to form a layer containing a block copolymer, Phase-separating the layer containing the block copolymer, A method for producing a structure having a phase separation structure, comprising:

Effects of the Invention

[0021] According to the present invention, it is possible to provide a resin composition for forming a phase separation structure capable of forming a phase separation structure with reduced pattern roughness and pattern errors, and a method for manufacturing a structure including the phase separation structure using the same.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0023] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present invention.

[0024] In this specification, "aliphatic" is a relative concept with respect to aromatic, and means a group, compound, etc. that does not have aromaticity. "Alkyl group" means a linear or branched monovalent saturated hydrocarbon group unless otherwise specified. The same applies to the alkyl group in an alkoxy group. "Cycloalkyl group" means a monocyclic cyclic saturated hydrocarbon group unless otherwise specified. "Alkylene group" means a linear or branched divalent saturated hydrocarbon group unless otherwise specified. "Haloalkyl group" means a group in which some or all of the hydrogen atoms of an alkyl group are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. "Fluoroalkyl group" or "fluoroalkylene group" means a group in which some or all of the hydrogen atoms of an alkyl group or an alkylene group are substituted with fluorine atoms. "Constituent unit" means a monomer unit (monomeric unit) that constitutes a polymer compound (resin, polymer, copolymer). "Derived constituent unit" means a constituent unit formed by cleavage of an ethylenic double bond or a cyclic ether. When it is described as "may have a substituent", it includes both the case of substituting a hydrogen atom (-H) with a monovalent group and the case of substituting a methylene group (-CH2-) with a divalent group. "Exposure" means irradiation with radiation in general. "α-position (α-carbon atom)" means, unless otherwise specified, the carbon atom to which the side chain of a block copolymer is bonded. The "α-carbon atom" of a methyl methacrylate unit means the carbon atom to which the carbonyl group of methacrylic acid is bonded. The "α-carbon atom" of a styrene unit means the carbon atom to which the benzene ring is bonded. "Number average molecular weight" (Mn) and "weight average molecular weight" (Mw) mean, unless otherwise specified, the number average molecular weight and weight average molecular weight in terms of standard polystyrene conversion determined by gel permeation chromatography (GPC) measurement (solvent: tetrahydrofuran (THF), flow rate (sample injection volume): 20 μL, column: TOSOH TSK Gel Super HM-N (three columns in series), column temperature: 40 °C, flow rate: 0.6 mL / min, detector: differential refractometer (RI)). When the value of Mn or Mw is -1 attached with the unit (gmol In this specification, depending on the structure represented by a chemical formula, there may be asymmetric carbons, and enantiomers or diastereomers may exist. In such a case, these isomers are represented by one formula. These isomers may be used alone or as a mixture.

[0025] ≪Resin Composition for Forming Phase Separation Structure≫ The resin composition for forming a phase separation structure contains a first block copolymer and a second block copolymer. The first block copolymer has a first a block and a first b block, and the second block copolymer has a second a block and a second b block. The first a block and the second a block are each independently composed of a polymer having a repeating structure of a structural unit represented by the following formula (b1), and the second b block is composed of a polymer having a repeating structure of a structural unit represented by the following formula (b2b). The number average molecular weight of the second block copolymer in terms of standard polystyrene determined by gel permeation chromatography (GPC) measurement is 40,000 or less. The first block copolymer satisfies either of the following (1) or (2). (1) The first b block is composed of a random copolymer having a structure in which a structural unit represented by the following formula (b2a) and a structural unit represented by the following formula (b2b) are randomly arranged. (2) In the first a block, n in the following formula (b1) is an integer of 1 or more and 5 or less, and the first b block is composed of a polymer having a repeating structure of a structural unit represented by the following formula (b2b).

Chemical formula

[0026] Since the first block copolymer satisfies any one of the above (1) or (2), it has a large interaction parameter and can form a structure with a smaller L0. In addition, the number average molecular weight of the second block copolymer is 40,000 or less, and from the relationship between the above interaction parameter and the polymerization degree product χ·N, the second block copolymer is less likely to phase separate. The inventors have found that by using such a second block copolymer that is less likely to phase separate in addition to the first block copolymer having a large interaction parameter, the phase separation rate can be improved and pattern roughness and pattern errors can be reduced.

[0027] <First block copolymer> The first block copolymer has a first a block and a first b block, and the first a block is composed of a polymer having a repeating structure of a structural unit represented by formula (b1) and satisfies any one of the above (1) or (2).

[0028] 〔First a block〕 The first a block is composed of a polymer having a repeating structure of a structural unit represented by the following formula (b1) (hereinafter also referred to as structural unit (b1)).

[0029]

Chemical formula

[0030] As the alkyl group which may have an oxygen atom and / or a silicon atom, an alkyl group which may be interrupted by an oxygen atom and may be substituted with an alkylsilyl group is preferable. Specifically, an alkyl group, an alkylsilyl group, an alkylsilylalkyl group, an alkylsilyloxy group, an alkylsilyloxyalkyl group, an alkoxy group and the like can be mentioned.

[0031] Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group and the like.

[0032] As the alkylsilyl group, a trialkylsilyl group is preferable. Specifically, a trimethylsilyl group and the like can be mentioned. As the alkylsilylalkyl group, a trialkylsilylalkyl group is preferable. Specifically, a trimethylsilylmethyl group, a 2-trimethylsilylethyl group, a 3-trimethylsilyl-n-propyl group and the like can be mentioned. As the alkylsilyloxy group, a trialkylsilyloxy group is preferable. Specifically, a trimethylsilyloxy group and the like can be mentioned. As the alkylsilyloxyalkyl group, a trialkylsilyloxyalkyl group is preferable. Specifically, a trimethylsilyloxymethyl group, a 2-trimethylsilyloxyethyl group, a 3-trimethylsilyloxy-n-propyl group and the like can be mentioned. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group and the like.

[0033] The total number of carbon atoms of the alkyl group, which may be interrupted by an oxygen atom and may be substituted with an alkylsilyl group, is preferably 1 or more and 10 or less, more preferably 1 or more and 5 or less, still more preferably 1 or more and 3 or less, and particularly preferably 1 or 2.

[0034] In the case of the above (1), n is preferably an integer of 0 or more and 3 or less, more preferably 0 or 1, and still more preferably 0. In the case of the above (2), n is an integer of 1 or more and 5 or less, preferably an integer of 1 or more and 3 or less, and more preferably 1.

[0035] 〔Block 1b〕 In the case of the above (1), Block 1b is composed of a random copolymer having a structure in which a structural unit represented by the following formula (b2a) (hereinafter also referred to as structural unit (b2a)) and a structural unit represented by the following formula (b2b) (hereinafter also referred to as structural unit (b2b)) are randomly arranged. In the case of the above (2), Block 1b is composed of a polymer having a repeating structure of a structural unit represented by formula (b2b).

[0036]

Chemical formula

[0037] (Structural unit (b2a)) R 2The number of carbon atoms of the monovalent organic group in is preferably 1 or more and 30 or less, more preferably 1 or more and 20 or less, still more preferably 1 or more and 10 or less, and particularly preferably 1 or more and 5 or less.

[0038] R 2 As the monovalent organic group in , an acyl group, a thioacyl group, an alkenyl group, or an alkyl group which may have a silyl group, a fluorine atom, a carboxy group, an amino group, a hydroxy group or a phosphoric acid group is preferable, and an acyl group or an alkyl group which may have a fluorine atom is more preferable.

[0039] R 2 The number of carbon atoms of the acyl group in is preferably 1 or more and 10 or less, more preferably 1 or more and 5 or less, and still more preferably 1 or more and 3 or less. R 2 Examples of the acyl group in include a formyl group, an acetyl group, and a propionyl group. Among them, an acetyl group is preferable. R 2 The number of carbon atoms of the thioacyl group in is preferably 1 or more and 10 or less, more preferably 1 or more and 5 or less, and still more preferably 1 or more and 3 or less. R 2 Examples of the thioacyl group in include a thioformyl group, a thioacetyl group, and a thiopropionyl group. Among them, a thioacetyl group is preferable. R 2 The number of carbon atoms of the alkenyl group in is preferably 2 or more and 10 or less, more preferably 3 or more and 5 or less. R 2 Examples of the alkenyl group in include an allyl group and an isopropenyl group. Among them, an allyl group is preferable.

[0040] R 2 The number of carbon atoms of the alkyl group in is preferably 1 or more and 20 or less, more preferably 1 or more and 20 or less, still more preferably 1 or more and 10 or less, and particularly preferably 1 or more and 5 or less. R 2 The alkyl group in is preferably linear. R 2Examples of the alkyl group in [compound name] include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, and the like. Among them, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, and an n-octyl group are preferable, and a methyl group, an ethyl group, and an n-propyl group are more preferable.

[0041] R 2 When the alkyl group in [compound name] has a silyl group, a fluorine atom, a carboxy group, an amino group, a hydroxy group, or a phosphoric acid group, the silyl group or the like is a substituent that replaces the hydrogen atom of the alkyl group. The number of hydrogen atoms to be replaced is preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less. R 2 Examples of the silyl group that the alkyl group in [compound name] may have include alkylsilyl groups such as a monoalkylsilyl group, a dialkylsilyl group, and a trialkylsilyl group. Among them, a trialkylsilyl group is preferable. The number of carbon atoms of the alkyl group in the alkylsilyl group is preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less. Examples of the alkyl group in the alkylsilyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and the like. Among them, a methyl group and an ethyl group are preferable, and a methyl group is more preferable.

[0042] R 3 The number of carbon atoms of the alkylene group in [compound name] is preferably 1 or more, more preferably 3 or more. Also, the number of carbon atoms of the alkylene group is preferably 10 or less, more preferably 8 or less, still more preferably 5 or less, and particularly preferably 4 or less, from the viewpoint of phase separation performance. The number of carbon atoms of the alkylene group is most preferably 3. R 3 The alkylene group in [compound name] is preferably linear.

[0043] R 3When the alkylene group in [it] has a hydroxy group, the number of hydroxy groups is preferably 1 or more and 3 or less, more preferably 1 or 2, and even more preferably 1.

[0044] In formula (b2a), R b2 Examples of the alkyl group having 1 to 5 carbon atoms as [it] include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a tert-pentyl group, and the like. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferable.

[0045] In formula (b2a), R b2 is preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom or a methyl group from the viewpoint of easy availability in industry, and even more preferably a methyl group.

[0046] The structural unit (b2a) is preferably a structural unit represented by the following formula (b2a-1). [Chemical formula] (In formula (b2a-1), R 31 is a hydrogen atom or a hydroxy group, n1 is an integer of 1 or more and 5 or less, n2 is an integer of 0 or more and 5 or less, X, R 2 , and R b2 are the same as X, R 2 , and R b2 in formula (b2a).)

[0047] n1 is preferably an integer of 1 or more and 3 or less, more preferably 1 or 2, and even more preferably 1. n2 is preferably an integer of 0 or more and 3 or less, more preferably 0 or 1, and even more preferably 1.

[0048] (Constituent unit (b2b)) R in formula (b2b) b2 is the same as R in formula (b2a) b2 .

[0049] When the first block copolymer satisfies the above (1), in the first b block, the ratio of the number of moles of the constituent unit represented by formula (b2a) to the total number of moles of the constituent unit represented by formula (b2a) and the number of moles of the constituent unit represented by formula (b2b) is preferably 0.90 or less, more preferably 0.30 or less, and even more preferably 0.01 or more and 0.10 or less from the viewpoint of more easily obtaining the effects of the present invention.

[0050] In the first block copolymer, the ratio of the number of moles of the constituent unit of the first a block to the total number of moles of the constituent unit of the first a block and the number of moles of the constituent unit of the first b block is preferably 20 mol% or more and 80 mol% or less. The ratio of the number of moles of the constituent unit of the first a block is more preferably 30 mol% or more, and even more preferably 35 mol% or more. Also, the ratio of the number of moles of the constituent unit of the first a block is more preferably 75 mol% or less, and even more preferably 70 mol% or less.

[0051] The first block copolymer may have other blocks in addition to the first a block and the first b block. In a preferred embodiment, the first block copolymer is a diblock copolymer composed of the first a block and the first b block.

[0052] The number average molecular weight (Mn) of the first block copolymer is not particularly limited, but is preferably 3,000 or more and 100,000 or less, more preferably 6,000 or more and 70,000 or less, even more preferably 8,000 or more and 50,000 or less, and particularly preferably 10,000 or more and 40,000 or less. The molecular weight distribution (Mw / Mn) of each block constituting the block copolymer is preferably 1.0 or more and 1.5 or less, more preferably 1.0 or more and 1.4 or less, and even more preferably 1.0 or more and 1.3 or less.

[0053] 〔Method for producing the first block copolymer〕 The first block copolymer can be produced by a known method. For example, it can be produced by a production method similar to the production method described in JP-A-2022-20519.

[0054] <Second block copolymer> The second block copolymer has a 2a block and a 2b block. The 2a block is composed of a polymer having a repeating structure of a structural unit represented by formula (b1), and the 2b block is composed of a polymer having a repeating structure of a structural unit represented by formula (b2b). The number average molecular weight of the second block copolymer in terms of standard polystyrene determined by gel permeation chromatography (GPC) measurement is 40,000 or less.

Chemical formula

[0055] A preferred embodiment of the structural unit represented by formula (b1) in the 2a block is the same as the structural unit represented by formula (b1) in the 1a block.

[0056] In the block of 2a, n in the formula (b1) is preferably 0. Thereby, when the second block copolymer is used, phase separation is less likely to occur, and the effects of the present invention are more easily obtained.

[0057] A preferred embodiment of the structural unit represented by the formula (b2b) in the block of 2b is the same as that of the structural unit represented by the formula (b2b) in the block of 1b.

[0058] In the second block copolymer, the ratio of the number of moles of the structural units of the 2a block to the total number of moles of the structural units of the 2a block and the structural units of the 2b block is preferably 20 mol% or more and 80 mol% or less. The ratio of the number of moles of the structural units of the 2a block is more preferably 30 mol% or more, and even more preferably 35 mol% or more. Also, the ratio of the number of moles of the structural units of the 2a block is more preferably 75 mol% or less, and even more preferably 70 mol% or less.

[0059] In addition to the 2a block and the 2b block, the second block copolymer may have other blocks. In a preferred embodiment, the second block copolymer is a diblock copolymer composed of the 2a block and the 2b block.

[0060] The number average molecular weight (Mn) of the second block copolymer is 40,000 or less, preferably 3,000 or more and 40,000 or less, more preferably 6,000 or more and 40,000 or less, even more preferably 8,000 or more and 35,000 or less, and particularly preferably 10,000 or more and 35,000 or less. The molecular weight dispersity (Mw / Mn) of each block constituting the block copolymer is preferably 1.0 or more and 1.5 or less, more preferably 1.0 or more and 1.4 or less, and even more preferably 1.0 or more and 1.3 or less.

[0061] The ratio of the mass of the first block copolymer to the total of the mass of the first block copolymer and the mass of the second block copolymer is preferably 30% by mass or more and 95% by mass or less, more preferably 40% by mass or more and 85% by mass or less, still more preferably 40% by mass or more and 70% by mass or less, and particularly preferably 40% by mass or more and 60% by mass or less. When within the above numerical range, the effects of the present invention are more easily obtained.

[0062] <Organic solvent component> The resin composition for forming a phase separation structure preferably contains an organic solvent. As the organic solvent component, any organic solvent can be used as long as it can dissolve each component to be used and form a uniform solution. Conventionally, any organic solvent selected from known organic solvents as the solvent of a composition mainly composed of a resin can be used.

[0063] As the organic solvent component, for example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol; monoacetates of polyhydric alcohols such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate; monoalkyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether of the polyhydric alcohols or compounds having an ether bond such as monophenyl ether, etc., derivatives of polyhydric alcohols [among these, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferred]; cyclic ethers such as dioxane, and esters other than monoacetates of polyhydric alcohols and derivatives of the aforementioned polyhydric alcohols, such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethyl benzene, diethyl benzene, pentyl benzene, isopropyl benzene, toluene, xylene, cymene, mesitylene, etc. The organic solvent component may be used alone or as a mixed solvent of two or more kinds. Among them, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone, and ethyl lactate (EL) are preferred.

[0064] The organic solvent component contained in the resin composition for forming a phase separation structure is not particularly limited. The organic solvent component is appropriately set according to the coating film thickness so that the concentration of the resin composition for forming a phase separation structure is a coatable concentration. The organic solvent component is generally used so that the solid content concentration of the resin composition for forming a phase separation structure is in the range of 0.2% by mass or more and 70% by mass or less, preferably 0.2% by mass or more and 50% by mass or less.

[0065] <Optional component> The resin composition for forming a phase separation structure may contain optional components other than the block copolymer and the organic solvent component described above. Examples of the optional components include other resins, surfactants, dissolution inhibitors, plasticizers, stabilizers, colorants, anti-halation agents, dyes, sensitizers, base proliferators, basic compounds, and the like.

[0066] ≪Method for manufacturing a structure including a phase separation structure≫ The method for manufacturing a structure including a phase separation structure includes applying a resin composition for forming a phase separation structure on a support to form a layer containing a block copolymer (hereinafter referred to as "step (i)"), and phase-separating the layer containing the block copolymer (hereinafter referred to as "step (ii)"). Hereinafter, the method for manufacturing a structure including such a phase separation structure will be specifically described with reference to FIG. 1. However, the method for manufacturing a structure including a phase separation structure is not limited to the embodiment specifically shown in FIG. 1.

[0067] FIG. 1 shows an example of an embodiment of the method for manufacturing a structure including a phase separation structure. In the embodiment shown in FIG. 1, first, a primer is applied on a support 1 to form a primer layer 2 (FIG. 1(I)). Next, a resin composition for forming a phase separation structure is applied on the primer layer 2 to form a layer containing a block copolymer (BCP layer) 3 (FIG. 1(II); the above is step (i)). Next, heating and annealing are performed to phase-separate the BCP layer 3 into phase 3a and phase 3b (FIG. 1(III); step (ii)). According to the manufacturing method of such an embodiment, that is, the manufacturing method having steps (i) and (ii), a structure 3' including a phase separation structure is manufactured on a support 1 on which an undercoat layer 2 is formed.

[0068] <Step (i)> In step (i), a resin composition for forming a phase separation structure is applied onto the support 1 to form a BCP layer 3. In the embodiment shown in FIG. 1, first, an undercoat agent is applied onto the support 1 to form an undercoat layer 2. By providing the undercoat layer 2 on the support 1, the hydrophilic-hydrophobic balance between the surface of the support 1 and the layer containing the block copolymer (BCP layer) 3 can be achieved. That is, when the undercoat layer 2 contains a resin component having a structural unit constituting the first a block, the adhesion between the phase composed of the first a block in the BCP layer 3 and the support 1 is enhanced. When the undercoat layer 2 contains a resin component having a structural unit constituting the first b block, the adhesion between the phase composed of the first b block in the BCP layer 3 and the support 1 is enhanced. Accordingly, due to the phase separation of the BCP layer 3, a phase separation structure oriented in the direction perpendicular to the surface of the support 1 is likely to be formed.

[0069] Undercoat agent: As the undercoat agent, a resin composition can be used. The resin composition for the undercoat agent can be appropriately selected from conventionally known resin compositions used for forming thin films according to the types of blocks constituting the block copolymer. The resin composition for the undercoat agent may be, for example, a thermopolymerizable resin composition, or a photosensitive resin composition such as a positive resist composition or a negative resist composition. Alternatively, a non-polymerizable film formed by applying a compound as a surface treatment agent may be used as the undercoat layer. For example, a siloxane-based organic monolayer film formed using phenethyltrichlorosilane, octadecyltrichlorosilane, hexamethyldisilazane, etc. as the surface treatment agent can also be suitably used as the undercoat layer.

[0070] Examples of such resin compositions include resin compositions containing a resin having both the structural units constituting the first a block and the first b block, and resin compositions containing a resin having both structural units highly compatible with each block constituting the block copolymer. Examples of the resin composition for the undercoat agent include compositions containing a resin having both styrene and methyl methacrylate as structural units, and compounds or compositions containing both a site highly compatible with styrene such as an aromatic ring and a site highly compatible with methyl methacrylate (a highly polar functional group or the like). It is preferable to use such compounds or compositions. Examples of the resin having both styrene and methyl methacrylate as structural units include a random copolymer of styrene and methyl methacrylate, an alternating polymer of styrene and methyl methacrylate (a polymer in which each monomer is copolymerized alternately), and the like. Examples of the composition containing both a site highly compatible with styrene and a site highly compatible with methyl methacrylate include, for example, a composition containing a resin obtained by polymerizing, as monomers, at least a monomer having an aromatic ring and a monomer having a highly polar functional group. Examples of the monomer having an aromatic ring include aryl groups obtained by removing one hydrogen atom from the ring of aromatic hydrocarbons such as phenyl group, biphenyl group, fluorenyl group, naphthyl group, anthryl group, phenanthryl group, or heteroaryl groups in which some of the carbon atoms constituting the ring of these groups are substituted with heteroatoms such as oxygen atom, sulfur atom, nitrogen atom, etc. Examples of the monomer having a highly polar functional group include monomers having a trimethoxysilyl group, trichlorosilyl group, epoxy group, glycidyl group, carboxy group, hydroxy group, cyano group, hydroxyalkyl group in which some of the hydrogen atoms of the alkyl group are substituted with hydroxy groups, and the like. In addition, examples of the compound containing both a site having a high affinity for styrene and a site having a high affinity for methyl methacrylate include compounds containing both an aryl group such as phenethyltrichlorosilane and a highly polar functional group, and compounds containing both an alkyl group such as an alkylsilane compound and a highly polar functional group.

[0071] The resin composition for the undercoat agent can be produced by dissolving the aforementioned resin in a solvent. Such a solvent may be any solvent that can dissolve each component to be used and form a uniform solution. For example, solvents similar to the organic solvent components exemplified in the description of the resin composition for forming a phase separation structure can be mentioned.

[0072] The type of the support 1 is not particularly limited as long as the resin composition can be applied on its surface. For example, substrates made of inorganic substances such as silicon, metals (copper, chromium, iron, aluminum, etc.), glass, titanium oxide, silica, mica; substrates made of oxides such as SiO2; substrates made of nitrides such as SiN; substrates made of oxynitrides such as SiON; substrates made of organic substances such as acrylic resin, polystyrene, cellulose, cellulose acetate, phenolic resin can be mentioned. Among these, a silicon substrate (Si substrate) or a metal substrate is preferable, an Si substrate or a copper substrate (Cu substrate) is more preferable, and an Si substrate is particularly preferable. The size and shape of the support 1 are not particularly limited. The support 1 does not necessarily have to have a smooth surface, and substrates of various shapes can be appropriately selected. For example, substrates having a curved surface, flat plates with a concavo-convex surface, substrates in the shape of flakes, etc. can be mentioned.

[0073] An inorganic and / or organic film may be provided on the surface of the support 1. Examples of the inorganic film include an inorganic antireflection film (inorganic BARC). Examples of the organic film include an organic antireflection film (organic BARC). The inorganic film can be formed, for example, by coating an inorganic antireflection film composition such as a silicon-based material on the support and performing firing or the like. The organic film can be formed, for example, by applying a material for forming an organic film, in which a resin component or the like constituting the film is dissolved in an organic solvent, onto a substrate using a spinner or the like, and preferably baking it under heating conditions of 200°C or higher and 300°C or lower, preferably for 30 seconds or longer and 300 seconds or shorter, more preferably for 60 seconds or longer and 180 seconds or shorter. This material for forming an organic film does not necessarily require sensitivity to light or an electron beam like a resist film, and may or may not have sensitivity. Specifically, a resist or resin generally used in the manufacture of semiconductor elements and liquid crystal display elements can be used. Also, by etching the organic film using a pattern made of a block copolymer formed by processing the BCP layer 3, the pattern can be transferred to the organic film to form an organic film pattern. Therefore, the material for forming an organic film is preferably a material that can form an organic film that can be etched, particularly dry-etched. Among them, it is preferably a material that can form an organic film that can be etched, such as oxygen plasma etching. Such a material for forming an organic film may be a material conventionally used for forming an organic film such as an organic BARC. For example, the ARC series manufactured by Nissan Chemical Industries, Ltd., the AR series manufactured by Rohm and Haas, the SWK series manufactured by Tokyo Ohka Kogyo Co., Ltd., etc. can be mentioned.

[0074] The method for forming the underlayer agent layer 2 by applying the underlayer agent onto the support 1 is not particularly limited and can be formed by a conventionally known method. For example, the underlayer agent can be applied onto the support 1 by a conventionally known method such as spin coating or using a spinner to form a coating film, and the underlayer agent layer 2 can be formed by drying it. As a method for drying the coating film, it is sufficient if the solvent contained in the underlayer agent can be volatilized, and examples include a baking method. At this time, the baking temperature is preferably 80°C or higher and 300°C or lower, more preferably 180°C or higher and 270°C or lower, and even more preferably 220°C or higher and 250°C or lower. The baking time is preferably 30 seconds or longer and 600 seconds or shorter, more preferably 60 seconds or longer and 600 seconds or shorter. The thickness of the undercoat layer 2 after drying of the coating film is preferably about 10 nm or more and 100 nm or less, more preferably about 40 nm or more and 90 nm or less.

[0075] Before forming the undercoat layer 2 on the support 1, the surface of the support 1 may be washed in advance. By washing the surface of the support 1, the coatability of the undercoat agent is improved. As the washing treatment method, a conventionally known method can be used, for example, oxygen plasma treatment, ozone oxidation treatment, acid-alkali treatment, chemical modification treatment, etc.

[0076] After forming the undercoat layer 2, if necessary, the undercoat layer 2 may be rinsed using a rinse liquid such as a solvent. By this rinsing, uncrosslinked portions in the undercoat layer 2 are removed, so the affinity with at least one block constituting the block copolymer is improved, and a phase separation structure composed of a cylinder structure oriented in the direction perpendicular to the surface of the support 1 is likely to be formed. The rinse liquid only needs to be able to dissolve the uncrosslinked portion, and solvents such as propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), ethyl lactate (EL), or commercially available thinner liquids can be used. Also, after this washing, post-baking may be performed to volatilize the rinse liquid. The temperature condition of this post-baking is preferably 80°C or more and 300°C or less, more preferably 100°C or more and 270°C or less. The baking time is preferably 30 seconds or more and 500 seconds or less, more preferably 60 seconds or more and 240 seconds or less. The thickness of the undercoat layer 2 after such post-baking is preferably about 1 nm or more and 10 nm or less, more preferably about 2 nm or more and 7 nm or less.

[0077] Next, a layer (BCP layer) 3 containing a block copolymer is formed on the undercoat layer 2. As a method for forming the BCP layer 3 on the underlayer 2, there are no particular limitations. For example, a method can be employed where the resin composition for forming the phase separation structure of the above-described embodiment is applied onto the underlayer 2 using a conventionally known method such as spin coating or a spinner to form a coating film, followed by drying.

[0078] The thickness of the BCP layer 3 only needs to be sufficient for phase separation to occur. Considering the type of the support 1, or the structural period size of the phase separation structure to be formed or the uniformity of the nanostructures, etc., it is preferably 20 nm or more and 100 nm or less, and more preferably 20 nm or more and 80 nm or less. For example, when the support 1 is a Si substrate, the thickness of the BCP layer 3 is preferably adjusted to be 10 nm or more and 100 nm or less, and more preferably 20 nm or more and 80 nm or less.

[0079] <Step (ii)> In step (ii), the BCP layer 3 formed on the support 1 is phase-separated. By heating the support 1 after step (i) and performing an annealing treatment, a phase separation structure is formed such that at least a part of the surface of the support 1 is exposed by selective removal of the block copolymer. That is, a structure 3' including a phase separation structure phase-separated into phase 3a and phase 3b is manufactured on the support 1. The temperature condition for the annealing treatment is preferably carried out at a temperature equal to or higher than the glass transition temperature of the block copolymer being used and lower than the thermal decomposition temperature. For example, when the block copolymer is a polystyrene - polymethyl methacrylate (PS - PMMA) block copolymer (weight average molecular weight of 5000 or more and 100000 or less), it is preferably 180°C or more and 270°C or less. The heating time is preferably 30 seconds or more and 3600 seconds or less. Also, the annealing treatment is preferably carried out in a gas with low reactivity such as nitrogen.

[0080] <Optional Step> The method for manufacturing a structure including a phase separation structure is not limited to the above-described embodiment and may have steps (optional steps) other than steps (i) and (ii).

[0081] Examples of such an arbitrary step include a step of selectively removing a phase composed of at least one of the first block and the second block constituting the block copolymer in the BCP layer 3 (hereinafter referred to as "step (iii)"), a step of forming a guide pattern, and the like.

[0082] · Regarding step (iii) In step (iii), a phase composed of at least one of the first block and the second block constituting the block copolymer in the BCP layer formed on the undercoat layer 2 is selectively removed. Thereby, a fine pattern (polymer nanostructure) is formed.

[0083] Examples of the method of selectively removing the phase composed of the block include a method of performing oxygen plasma treatment on the BCP layer, a method of performing hydrogen plasma treatment, and the like. For example, after phase-separating the BCP layer containing the block copolymer, by performing oxygen plasma treatment, hydrogen plasma treatment, etc. on the BCP layer, the phase composed of the first a block (b1) is not selectively removed, and the phase composed of the first b block (b2) is selectively removed.

[0084] FIG. 2 shows an example of an embodiment of step (iii). In the embodiment shown in FIG. 2, by performing oxygen plasma treatment on the structure 3' manufactured on the support 1 in step (ii), the phase 3a is selectively removed, and a pattern (polymer nanostructure) composed of the separated phase 3b is formed. In this case, the phase 3b is the phase composed of the first block, and the phase 3a is the phase composed of the second block.

[0085] The support 1 on which a pattern is formed by phase separation of the BCP layer 3 made of the block copolymer as described above can be used as it is, but by further heating, the shape of the pattern (polymer nanostructure) on the support 1 can also be changed. The temperature condition for heating is preferably equal to or higher than the glass transition temperature of the block copolymer to be used and lower than the thermal decomposition temperature. Further, the heating is preferably performed in a gas with low reactivity such as nitrogen.

[0086] ·Regarding the guide pattern formation step In the method for producing a structure including a phase separation structure, a step of providing a guide pattern on the underlayer agent layer (guide pattern formation step) may be included between the above-described steps (i) and (ii). Thereby, it becomes possible to control the arrangement structure of the phase separation structure. For example, even in the case of a block copolymer in which a random fingerprint-like phase separation structure is formed when no guide pattern is provided, by providing a groove structure of a resist film on the surface of the underlayer agent layer, a phase separation structure oriented along the grooves can be obtained. Based on such a principle, a guide pattern may be provided on the underlayer agent layer 2. Further, when the surface of the guide pattern has an affinity with any of the blocks constituting the block copolymer, a phase separation structure composed of a cylinder structure oriented in a direction perpendicular to the surface of the support is likely to be formed.

[0087] The guide pattern can be formed using, for example, a resist composition. The resist composition for forming the guide pattern can be appropriately selected from resist compositions generally used for forming resist patterns and modified products thereof, and a composition having an affinity with any of the blocks constituting the block copolymer. As the resist composition, either a positive resist composition for forming a positive pattern in which the exposed portion of the resist film is dissolved and removed or a negative resist composition for forming a negative pattern in which the unexposed portion of the resist film is dissolved and removed may be used, but a negative resist composition is preferred. As the negative resist composition, for example, a resist composition containing an acid generator and a base material component whose solubility in a developer containing an organic solvent decreases due to the action of an acid, and the base material component contains a resin component having a structural unit that decomposes due to the action of an acid and increases in polarity is preferred. After the BCP composition is poured onto the primer layer on which the guide pattern is formed, an annealing process is performed to cause phase separation. Therefore, as the resist composition for forming the guide pattern, a composition capable of forming a resist film excellent in solvent resistance and heat resistance is preferable.

Example

[0088] The present invention will be described in more detail based on the examples, but the present invention is not limited by these examples.

[0089] Hereinafter, the block copolymers used in the examples and comparative examples will be described. For BCP(1-1) to BCP(1-3), they were prepared with reference to the examples of JP 2022-20519 A. For BCP(1-4) to BCP(1-6) and BCP(1-0), they were prepared with reference to the examples of JP 2022-20519 A and using 1-propanethiol, 1-octanethiol, or thioacetic acid instead of 2,2,2-trifluoroethanethiol, respectively. BCP(1-1) to BCP(1-3): A block copolymer composed of a block made of polystyrene and a block made of a random copolymer of 2-hydroxy-3-(2,2,2-trifluoroethylsulfanyl)propyl methacrylate and methyl methacrylate BCP(1-4) and BCP(1-10): A block copolymer composed of a block made of polystyrene and a block made of a random copolymer of 2-hydroxy-3-(propylsulfanyl)propyl methacrylate and methyl methacrylate BCP(1-5): A block copolymer composed of a block made of polystyrene and a block made of a random copolymer of 2-hydroxy-3-(octylsulfanyl)propyl methacrylate and methyl methacrylate BCP(1-6): A block copolymer composed of a block made of polystyrene and a block made of a random copolymer of 2-hydroxy-3-(acetylsulfanyl)propyl methacrylate and methyl methacrylate BCP(1-7) and BCP(1-11): Block copolymer of a block consisting of polystyrene and a block consisting of a random copolymer of 2-methoxyethyl methacrylate and methyl methacrylate BCP(1-8) and BCP(1-12): Block copolymer of a block consisting of polystyrene and a block consisting of a random copolymer of 2-hydroxyethyl methacrylate and methyl methacrylate BCP(1-9) and BCP(1-13): Block copolymer of a block consisting of poly(4-ethylstyrene) and a block consisting of polymethyl methacrylate

[0090] BCP(2-1) to BCP(2-6): Block copolymer of a block consisting of polystyrene and a block consisting of polymethyl methacrylate

[0091] <Measurement of molar ratio of constituent units of each block> Using an NMR apparatus (manufactured by Bruker, equipped with a CryoProbe) 1 By 1H-NMR measurement (600 MHz, deuterated acetone), the integral ratio value (area ratio) was measured from the chemical shifts of the constituent units of each block of the block copolymer, and the molar ratio of the constituent units of each block was calculated.

[0092] The number average molecular weight (Mn), molecular weight dispersity (PDI = Mw / Mn) of each of the above block copolymers, and the ratio (x:y:z) of the number of moles of the constituent unit (b1), the number of moles of the constituent unit (b2a), and the number of moles of the constituent unit (b2b) to the total number of moles of all constituent units, and the ratio (y / (y + z)) of the number of moles of the constituent unit (b2a) to the total number of moles of the constituent units (b2a) and (b2b), and L o These are summarized in Table 1 and Table 2.

[0093]

Table 1

[0094]

Table 2

[0095] <Preparation of Resin Composition for Forming Phase Separation Structure and Manufacture of Structure Containing Phase Separation Structure> Each BCP shown in Table 3 and Table 4 was mixed and dissolved with propylene glycol monomethyl ether to prepare a resin composition for forming a phase separation structure (solid content concentration: 1.0% by mass) for each example.

[0096] A neutralization film composition solution (underlayer agent) prepared in a 2 wt% PGMEA solution was applied onto a 12-inch silicon wafer at 1500 rpm using a spinner, and baked at 250 °C for 300 seconds in a nitrogen atmosphere to dry, thereby forming a layer (underlayer agent layer) composed of a neutralization film with a film thickness of 60 nm on the substrate. Next, the portion other than the portion where the neutralization film was in close contact with the substrate was removed with OK73 thinner (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.), post-baked at 100 °C for 60 seconds, and after spin-coating the resin composition for purifying the phase separation structure of each example on the layer composed of the neutralization film, soft-baked at 90 °C for 60 seconds to form a BCP layer with a film thickness of 25 nm. As the neutralization film composition solution, a propylene glycol monomethyl ether acetate solution of a copolymer having styrene (St) units, methyl methacrylate (MMA) units, and 2-hydroxyethyl methacrylate (HEMA) units (St / MMA / HEMA = 82 / 12 / 6 (mol%), number average molecular weight 25,700, weight average molecular weight (Mw) 45,300, dispersity (PDI) 1.76) was used.

[0097] The formed resin composition layer was annealed in a nitrogen atmosphere to form a phase separation structure. The annealing temperature and time were 220 °C for 5 minutes in the case of Examples 1 to 11 and Comparative Example 1 (lamellar structure), and 200 °C for 15 minutes in the case of Examples 12 to 16 and Comparative Example 2 (cylindrical structure).

[0098] Subsequently, in Examples 12 to 16 and Comparative Example 2, for the substrate on which the phase separation structure was formed, ultraviolet rays (λ172 nm, 160 mJ) were irradiated in a nitrogen atmosphere using CLEAN TRACK LITHIUS Pro-Z (manufactured by Tokyo Electron Limited). Subsequently, development was performed with isopropyl alcohol to selectively remove the phase containing polymethyl methacrylate, and a hole pattern was formed.

[0099] The following evaluations were conducted. The results of Examples 1 to 11 and Comparative Example 1 are shown in Table 3, and the results of Examples 12 to 16 and Comparative Example 2 are shown in Table 4. Also, the image of Example 3 is shown in Figure 3, the image of Comparative Example 1 is shown in Figure 4, the image of Example 12 is shown in Figure 5, and the image of Comparative Example 2 is shown in Figure 6.

[0100] (Evaluation of FER (Fingerprint Edge Roughness)) For 100 images of the surfaces (phase separation states) of the substrates obtained in Examples 1 to 11 and Comparative Example 1, 3σ, which is a measure indicating FER, was determined. This is shown in Table 3 as "FER (nm)". "3σ" was measured by observing the fingerprint pattern of the obtained surface (phase separation state) of the substrate with a length-measuring SEM (scanning electron microscope, trade name CG6300, manufactured by Hitachi High-Technologies Corporation, acceleration voltage 800 eV, current value 15 pA, Frame 256, magnification 100k (image of 1350 nm square)) using off-line length-measuring software (manufactured by Hitachi High-Technologies Corporation). 3σ indicates three times the standard deviation (σ) (unit: nm) obtained from the measurement results. The smaller the value of 3σ, the smaller the roughness of the structure including the phase separation structure, meaning that a structure with a better shape with reduced roughness generation was obtained.

[0101] (Evaluation of Grain Number) For each of the hole patterns formed in Examples 12 to 16 and Comparative Example 2, image analysis was performed using the off-line length-measuring software, and the number of grains was determined from an image of 1350 nm square. This is shown in Table 4 as "Grain (pieces)". The fewer the number of Grains, the more continuously the hole patterns with the same pitch and the same shape are formed, which means an increase in the process margin and a reduction in defects.

[0102] (Annealing temperature) In the production of the structure including the above phase separation structure, the annealing temperature was changed every 10°C, and the highest temperature among the temperatures at which normal orientation occurred was determined. The results are shown in Tables 3 and 4. Note that normal orientation means that in the SEM images of the substrate after annealing, in Examples 1 to 11 and Comparative Example 1, the ratio of the finger print structure without defects is 80% or more, and in Examples 12 to 16 and Comparative Example 2, the ratio of the vertical random hole structure is 80% or more.

[0103]

Table 3

[0104]

Table 4

[0105] As shown in Tables 3 and 4, it was confirmed that in Examples 1 to 11, a phase separation structure with a low FER could be formed. Also, in Examples 12 to 16, it was confirmed that a phase separation structure with a small number of Grains could be formed. Therefore, it can be seen that the resin composition for forming a phase separation structure used in Examples 1 to 16 can form a phase separation structure with reduced pattern roughness and pattern error. Furthermore, in these examples, it was confirmed that normal orientation still occurred even when the annealing temperature was raised.

Claims

1. A resin composition for forming a phase separation structure, comprising a first block copolymer and a second block copolymer, wherein the first block copolymer has a first a block and a first b block, the second block copolymer has a second a block and a second b block, the first a block and the second a block are each independently composed of a polymer having a repeating structure of a structural unit represented by the following formula (b1), the second b block is composed of a polymer having a repeating structure of a structural unit represented by the following formula (b2b), the number average molecular weight of the second block copolymer in terms of standard polystyrene determined by gel permeation chromatography (GPC) measurement is 40,000 or less, the resin composition for forming a phase separation structure, wherein the first block copolymer satisfies any one of the following (1) or (2). (1) The first b block is composed of a random copolymer having a structure in which a structural unit represented by the following formula (b2a) and a structural unit represented by the following formula (b2b) are randomly arranged. (2) In the first a block, n in the following formula (b1) is an integer of 1 or more and 5 or less, the first b block is composed of a polymer having a repeating structure of a structural unit represented by the following formula (b2b). 【Chemical 1】 (In formula (b1), R ｂ１ is a hydrogen atom or a methyl group, R １ is an alkyl group which may have an oxygen atom or a silicon atom, n is an integer of 0 or more and 5 or less, and when n is an integer of 2 or more, a plurality of R １ may be the same or different from each other, In formula (b2a), X is a sulfur atom or an oxygen atom, and R ３ is an alkylene group which may have a hydroxy group, and R ２ is a hydrogen atom or a monovalent organic group. In formula (b2a) and formula (b2b), R ｂ２ is, independently of one another, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and a plurality of R ｂ２ may be the same or different. )

2. R in the formula (b2a) ２ is a hydrogen atom, an acyl group, a thioacyl group, an alkenyl group, or an alkyl group which may have a silyl group, a fluorine atom, a carboxy group, an amino group, a hydroxy group or a phosphate group, The resin composition for forming a phase separation structure according to claim 1.

3. The resin composition for forming a phase separation structure according to claim 1, wherein the ratio of the mass of the first block copolymer to the total of the mass of the first block copolymer and the mass of the second block copolymer is 30% by mass or more and 95% by mass or less.

4. The ratio of the number of moles of the structural unit of the first a block to the total of the number of moles of the structural unit of the first a block and the number of moles of the structural unit of the first b block is 20 mol% or more and 80 mol% or less, The ratio of the number of moles of the structural unit of the second a block to the total of the number of moles of the structural unit of the second a block and the number of moles of the structural unit of the second b block is 20 mol% or more and 80 mol% or less. The resin composition for forming a phase separation structure according to claim 1.

5. When the first block copolymer satisfies the above (1), in the first b block, the ratio of the number of moles of the structural unit represented by the formula (b2a) to the total of the number of moles of the structural unit represented by the formula (b2a) and the number of moles of the structural unit represented by the formula (b2b) is 0.90 or less. The resin composition for forming a phase separation structure according to claim 1.

6. Coating the resin composition for forming a phase separation structure according to any one of claims 1 to 5 on a support to form a layer containing a block copolymer; Phase-separating the layer containing the block copolymer; A method for manufacturing a structure having a phase separation structure, comprising:

Images