Self-correcting directed self-assembly process using self-assembling block copolymers comprising cyclic cross-linkable groups

Abstract

The present application relates to self-assembled block copolymers containing cyclic cross-linkable groups and self-correcting directed self-assembly methods. The self-assembled block copolymers contain cyclic cross-linkable groups selected from one or more of the group consisting of fused saturated alicyclic aryl, cyclic amine aryl, cyclic ether, and saturated alicyclic aryl. The self-correcting directed self-assembly methods include a first directed self-assembly using a first self-assembled block copolymer, which is the self-assembled block copolymer containing cyclic cross-linkable groups described above, and cross-linking to obtain a first nanostructure, and using the first nanostructure to direct a second self-assembly of a second block copolymer to obtain a second nanostructure. The self-correcting directed self-assembly methods using the self-assembled block copolymers containing cyclic cross-linkable groups of the present application substantially reduce pattern defects and reduce line edge roughness and line width roughness.

Description

Technical Field

[0001] This disclosure relates to the field of guided self-assembly, and more particularly to a self-assembly block copolymer comprising cyclic crosslinkable groups and a self-correcting guided self-assembly method using the self-assembly block copolymer. Background Technology

[0002] In 2003, Paul Nealey's research group at the University of Wisconsin invented a method for preparing long-range ordered linear nanostructures perpendicular to the substrate by using chemical patterns to guide the assembly of diblock copolymer films (Nature, 2003, 424, 411). This method utilizes photolithography to prepare physical or chemically guided templates (such as trenches or chemically modified regions) on the substrate surface, controlling the arrangement and alignment of the nanostructures by restricting the spatial distribution direction of the block copolymers.

[0003] Ruiz et al. invented a method for guiding the self-assembly of columnar phase block copolymers using hexagonal lattice chemical patterns. They obtained sparse hexagonal lattice photoresist patterns using electron beam exposure, and then oxidized the exposed PS (polystyrene) molecules using plasma to obtain the hexagonal lattice chemical pattern. The period (L) of the chemical pattern... s The period (L0) is twice that of the block copolymer, thus achieving a 4-fold density increase in directed self-assembly (DSA) (Science, 2008, 321, 936).

[0004] Liu et al. invented an effective method for preparing chemical patterns for density-multiplying DSA (LiNeflow): First, a pre-pattern is formed on a PS (polystyrene) or PMMA (polymethyl methacrylate) homopolymer felt / brush by photolithography, then the desired size is obtained by plasma etching, and finally a random copolymer brush is backfilled to form a pattern with periodic chemical differences, thereby achieving 2x and 4x density-multiplying guided self-assembly (Macromolecules, 2011, 44, 1876; Macromolecules, 2013, 46, 1415).

[0005] Density-multiply guided self-assembly of block copolymers can yield nanostructures with smaller resolution than existing photolithography equipment, breaking through the resolution limits of photolithography. Compared with traditional photolithography, nanostructures prepared by guided self-assembly have three advantages in addition to highly accurate phase domain positioning: 1) Nanostructures obtained by guided self-assembly have lower edge roughness (LER) and linewidth roughness (LWR); 2) Block copolymer self-assembly is thermodynamically controlled, which can repair some defects caused by photolithography; 3) Density-multiply guided self-assembly can break through the resolution limits of photolithography equipment and obtain smaller nanostructures. As the wavelength of light sources gradually reaches its physical limit, the method of guiding the self-assembly of block copolymers to form regular patterns using physical or chemical methods has become one of the alternative solutions for 3nm and below process node technologies.

[0006] Currently, density-multiply guided self-assembly (DSA) typically employs block copolymers for one-step assembly. During density-multiply DSA, due to the template period (L... s Due to factors such as the matching of phase separation cycle (L0) with block copolymers, template quality, and assembly kinetics, defects such as dislocations and bridging often occur. At the same time, considering the need for pattern transfer, thicker films need to be prepared. However, increasing the film thickness will lead to more defects. Therefore, it is necessary to optimize polymer parameters, annealing conditions, and template parameters to reduce or eliminate defects.

[0007] Wan et al. (ACS Nano, 2017, 11, 7666) blended hydroxyl-terminated PS (PS-OH) and hydroxyl-terminated PMMA (PMMA-OH) with PS-b-PMMA to obtain ternary blends. These blends were then subjected to density-multiply guided self-assembly on a template prepared using a LiNe flow process. During assembly, PS-OH and PMMA-OH were confined within their respective phase domains (PS and PMMA domains) of PS-b-PMMA, then migrated to the vicinity of the substrate and underwent condensation reactions with silanol groups, inserting into the existing random copolymer molecular brush layer. The PS-b-PMMA and unreacted PS-OH and PMMA-OH were removed using a solvent, resulting in a chemical pattern of alternating PS and PMMA-rich homopolymer molecular brushes. This chemical pattern was then used to guide the 1:1 guided self-assembly of PS-b-PMMA. After grafting homopolymer molecular brushes, this technique requires the removal of PS-b-PMMA and unreacted PS-OH and PMMA-OH with solvents. Due to the solvent effect, the phase interface of the chemical pattern of the PS and PMMA-rich homopolymer molecular brushes is blurred, resulting in a large LER / LWR of the nanostructures obtained by guided self-assembly; at the same time, it may be difficult to eliminate defects.

[0008] Therefore, new processes or materials need to be developed to address the defects in the fabrication of nanostructures using density-multiplying DSA. Invention Overview

[0010] To address the shortcomings of density-multiplying DSA, this disclosure proposes a novel guided self-assembly block copolymer and a guided self-assembly method. This disclosure involves introducing cyclic crosslinkable groups into one or more blocks of the block copolymer, performing density-multiplying DSA on a template, and then treating it with heat or light to crosslink and solidify it. The solidified nanostructure is then used as a chemical template to guide the guided self-assembly of a second layer of the block copolymer.

[0011] On the one hand, this disclosure proposes a self-assembled block copolymer comprising one or more cyclic crosslinkable groups selected from the group consisting of fused saturated alicyclic aryl, cyclic amino aryl, cyclic ether, and saturated alicyclic aryl.

[0012] In some embodiments, the fused saturated alicyclic aryl group has the general formula (I):

[0013]

[0014] In some embodiments, the cyclic aminoaryl group has the general formula (II):

[0015]

[0016] In some embodiments, the cyclic ether group has the general formula (III):

[0017]

[0018] In some embodiments, the saturated alicyclic aryl group has the general formula (IV):

[0019]

[0020] In the above formulas, Indicates the linking site of the crosslinkable group in the self-assembled block copolymer; each R1 and each R2 is independently selected from (C1-C4) alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups, preferably (C1-C4) alkyl; each R A Each R B Each R C and each R D Each is independently selected from hydrogen, (C1-C4)alkyl, carboxyl, amino, nitro, hydroxyl, cyano, and amino, preferably hydrogen, (C1-C4)alkyl, or hydroxyl; R3, each R E Each R F Each R G and each R HEach is independently selected from hydrogen, (C1-C4)alkyl and substituted or unsubstituted phenyl, preferably hydrogen or (C1-C4)alkyl; a is an integer from 0 to 3; b is an integer from 0 to 4; m is an integer from 1 to 5; n is an integer from 2 to 5; p and q are each independently an integer from 0 to 4, and p+q is an integer from 1 to 4; Ph represents a substituted or unsubstituted phenylene; Cy represents a substituted or unsubstituted (C3-C4) saturated alicyclic hydrocarbon group.

[0021] In some embodiments, each substituent of the substituted phenyl group is independently selected from (C1-C4) alkyl, carboxyl, amino, nitro, hydroxyl, cyano, and amino groups.

[0022] In some embodiments, each substituent of the substituted phenylene group is independently selected from (C1-C4) alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups.

[0023] In some embodiments, each substituent of the substituted (C3-C4) saturated alicyclic hydrocarbon group is independently selected from (C1-C4) alkyl, carboxyl, amino, nitro, hydroxy, hydroxy-(C1-C4)alkyl, cyano and amino, preferably (C1-C4)alkyl or hydroxy-(C1-C4)alkyl.

[0024] In some embodiments, the cyclic crosslinkable group is selected from any one or more of the following formulas (V) to (XI):

[0025]

[0026] In the above formulas, R1, R2, R3, R E R F R G R H The definitions of a and b are the same as in claim 2; each of R4, each of R5 and each of R6, each of R7, each of R8, each of R9, and each of R 10 Each is independently selected from one or more of (C1-C4) alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups, preferably (C1-C4) alkyl; c, d, f, and h are each independently integers from 0 to 4, e is an integer from 0 to 6, g is an integer from 0 to 5, and i is an integer from 0 to 7.

[0027] In some embodiments, the cyclic crosslinkable group is selected from any one or more of the following group:

[0028]

[0029] On the other hand, this disclosure proposes a self-assembled block copolymer composition comprising the self-assembled block copolymer comprising cyclic crosslinkable groups proposed in this disclosure.

[0030] Furthermore, this disclosure proposes a guided self-assembly method for nanostructures, comprising:

[0031] A first nanostructure is obtained by first guided self-assembly using a first self-assembly block copolymer or a first self-assembly block copolymer composition and crosslinking, wherein the first self-assembly block copolymer is a self-assembly block copolymer containing cyclic crosslinkable groups as disclosed herein, and the first self-assembly block copolymer composition is a self-assembly block copolymer composition containing cyclic crosslinkable groups as disclosed herein.

[0032] In some embodiments, the method further includes performing a second guided self-assembly on the first nanostructure using a second self-assembly block copolymer or a second self-assembly block copolymer composition to obtain a second nanostructure.

[0033] In some embodiments, the crosslinking is performed after the first guided self-assembly is completed.

[0034] In another aspect, this disclosure proposes a method for forming patterns, which includes a guided self-assembly step using a self-assembly block copolymer or self-assembly block copolymer composition containing cyclic crosslinkable groups as proposed in this disclosure.

[0035] This disclosure utilizes density multiplication to guide self-assembly of crosslinkable block copolymers with a relatively small thickness, which can significantly reduce defects in the first layer. By using the first crosslinked layer as a new chemical pattern to guide the self-assembly of the second block copolymer, assembly kinetics are improved, defects are reduced, film thickness is increased, and minor defects that may arise during the assembly of the first layer are repaired, while simultaneously reducing LER / LWR. The thickness of the first block copolymer film can be controlled to a relatively small thickness, thereby significantly reducing density multiplication defects. The second block copolymer undergoes guided self-assembly on the first block copolymer film, significantly improving assembly kinetics, effectively reducing or eliminating defects generated by the template itself and during assembly, and greatly increasing the period and volume fraction window of the second block copolymer. Attached Figure Description

[0036] Figure 1 This is an exemplary self-rectified guided self-assembly (srDSA) flowchart based on this disclosure.

[0037] Figure 2 This is a cross-sectional schematic diagram of the assembly of layered phase materials according to Example 1, which is first performed by using a line template to conduct a 3x density multiplication DSA to guide the assembly of layered phase materials to form a first layer of nanostructure, and then guide the assembly of layered phase materials on it.

[0038] Figure 3The cross-linked nanostructure was obtained by using PS-bP (MMA-r-Oxe) block copolymer containing cyclic cross-linkable groups on a line template to perform 3-fold density multiplication guided self-assembly according to Example 1.

[0039] Figure 4 Therefore Figure 3 The nanostructure shown is used as a template to obtain the nanostructure through 1:1 guided self-assembly using PS-b-PMMA without crosslinking groups prepared in Example 1.

[0040] Figure 5 The nanostructure was obtained by direct self-assembly guided by 3 times density multiplication on a line template using PS-b-PMMA.

[0041] Figure 6 This is a cross-sectional schematic diagram of a first nanostructure, which is formed by first performing a 9-fold density multiplication DSA guided assembly of spherical phase materials using a tetragonal lattice template to form a first nanostructure, and then guiding the assembly of columnar phase materials on top of it. Detailed Implementation

[0042] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0043] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0044] In this document, the terms “contains,” “includes,” “containing,” and similar terms encompass the meanings of “basically composed of” and “composed of.” For example, when this document discloses “A contains B and C,” “A is basically composed of B and C” and “A is composed of B and C” should be considered as having been disclosed in this document.

[0045] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0046] Unless otherwise specified, percentages refer to mass percentages and proportions refer to mass ratios in this article.

[0047] In this document, when describing embodiments or examples, it should be understood that it is not intended to limit the invention to those embodiments or examples. Rather, all alternatives, modifications, and equivalents of the methods and materials described herein are covered within the scope defined by the claims.

[0048] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0049] In this invention, (alkylene) includes both alkyl and alkylene groups. An alkyl group refers to a monovalent saturated group with a straight-chain or branched structure composed of carbon and hydrogen atoms, while an alkylene group refers to a divalent saturated group with a straight-chain or branched structure composed of carbon and hydrogen atoms. In this invention, the number of carbon atoms preceding the group indicates the number of carbon atoms contained in the group. For example, C1 (alkylene) represents an alkylene group containing one carbon atom, i.e., (methylene). The (alkylene) applicable to this invention can be C1 to C10 (alkylene), such as C1 (alkylene), C2 (alkylene), C3 (alkylene), C4 (alkylene), C5 (alkylene), C6 (alkylene), C7 (alkylene), C8 (alkylene), C9 (alkylene), and C10 (alkylene).

[0050] In this invention, ()alkenyl groups include both alkenyl and alkenyl groups. An alkenyl group refers to a monovalent unsaturated group composed of carbon atoms and hydrogen atoms, having a straight-chain or branched structure and containing at least one carbon-carbon double bond. An alkenyl group refers to a divalent unsaturated group composed of carbon atoms and hydrogen atoms, having a straight-chain or branched structure and containing a carbon-carbon double bond. The alkenyl groups suitable for this invention can be C2-C10 alkenyl groups, such as C2, C3, C4, C5, C6, C7, C8, C9, and C10 alkenyl groups.

[0051] In this invention, (cycloalkylene) includes both cycloalkyl and cycloalkylene groups. A cycloalkyl group is a monovalent saturated group with an aliphatic ring structure composed of carbon and hydrogen atoms, and the cycloalkyl group is connected to other parts of the molecule through a carbon atom on the aliphatic ring. A cycloalkylene group is a divalent saturated group with an aliphatic ring structure composed of carbon and hydrogen atoms, and the cycloalkylene group is connected to other parts of the molecule through a carbon atom on the aliphatic ring. The (cycloalkylene) to which this invention is applicable can be C5-C10 (cycloalkylene) to which cycloalkylene is used, such as C5 (cycloalkylene), C6 (cycloalkylene), C7 (cycloalkylene), C8 (cycloalkylene), C9 (cycloalkylene), and C10 (cycloalkylene).

[0052] In this invention, (sub)cycloalkenyl groups include both cycloalkenyl and subcycloalkenyl groups. A cycloalkenyl group refers to a monovalent unsaturated group with an aliphatic ring structure, consisting of carbon and hydrogen atoms, containing at least one carbon-carbon double bond, and the cycloalkenyl group is connected to other parts of the molecule through a carbon atom on the aliphatic ring. A subcycloalkenyl group refers to a divalent unsaturated group with an aliphatic ring structure, consisting of carbon and hydrogen atoms, containing a carbon-carbon double bond, and the subcycloalkenyl group is connected to other parts of the molecule through a carbon atom on the aliphatic ring. The (sub)cycloalkenyl groups suitable for this invention can be C5-C10 (sub)cycloalkenyl groups, such as C5 (sub)cycloalkenyl, C6 (sub)cycloalkenyl, C7 (sub)cycloalkenyl, C8 (sub)cycloalkenyl, C9 (sub)cycloalkenyl, and C10 (sub)cycloalkenyl.

[0053] In this invention, hydrogen atoms include protium, deuterium, and tritium.

[0054] This disclosure addresses the problems of slow kinetics and defect-proneness in the commonly used one-step density-multiply guided self-assembly (DSA) method through a two-step guided self-assembly. It also overcomes issues such as blurred chemical template phase region interfaces, large LER / LWR of the assembled structure, and high defect density in existing technologies. In the first step of guided self-assembly (also referred to as the first guided self-assembly in this disclosure), a first self-assembly block copolymer is used. This first self-assembly block copolymer can be obtained by introducing a certain amount of specific crosslinkable groups into one or more blocks of a conventional self-assembly block copolymer. The first self-assembly block copolymer is crosslinked and cured by heating or light treatment during / after density-multiply DSA on a template. Then, the cured nanostructure (the first nanostructure) is used as a chemical template to guide the self-assembly of the second self-assembly block copolymer, i.e., the second step of guided self-assembly (also referred to as the second guided self-assembly in this disclosure), to obtain the second nanostructure. This process prepares the first layer of chemical pattern under thermodynamic control, resulting in a lower LER / LWR compared to existing technologies. Furthermore, the second layer guided self-assembly can repair any minor defects that may have been generated during the first layer density-multiply guided self-assembly. This two-step process is referred to in this disclosure as self-rectified guided self-assembly (srDSA), such as... Figure 1 As shown.

[0055] refer to Figure 1 The self-correcting guided self-assembly method disclosed herein may include, but is not limited to, the following steps:

[0056] 1) Provide templates;

[0057] 2) Choose any template to modify, such as using a molecular brush or molecular felt, plasma treatment, or no modification.

[0058] 3) First guided self-assembly is performed using the first self-assembly block copolymer, i.e., the self-assembly block copolymer or self-assembly block copolymer composition containing cyclic crosslinkable groups of the present invention is spin-coated onto a template, and then, for example, heat treatment or solvent treatment is applied to complete self-assembly, and crosslinking is completed under, for example, heat treatment or light irradiation (first density multiplication DSA and thermal crosslinking or photocrosslinking) to obtain a cured nanostructure (first nanostructure, i.e. first layer chemical pattern);

[0059] 4) A second guided self-assembly is performed on the first nanostructure using a second self-assembled block copolymer or a self-assembled block copolymer composition, i.e., the second self-assembled block copolymer or composition is coated on the first layer chemical pattern, and a second DSA is performed by, for example, heat treatment or solvent treatment, to obtain the second nanostructure.

[0060] By designing the structure of crosslinking groups and controlling the crosslinking temperature or light conditions of the crosslinkable block copolymer, the assembly kinetics are made faster than the crosslinking kinetics. This allows for controlled crosslinking to be completed after density-multiply guided self-assembly, and then the crosslinked nanostructure guides the second block copolymer to complete guided self-assembly, thus forming a defect-free nanostructure.

[0061] Regarding the template, this disclosure does not impose any particular limitation on the method of forming a template pattern on the substrate. It can be any method known to those skilled in the art, such as chemical, topological, optical, electron beam, mechanical, nanoimprint, etc., which can be used to etch the substrate, as well as new methods to be developed in the future.

[0062] For template modification, the choice must be made according to the template itself. For example, the template can be modified with a molecular brush or molecular felt, or subjected to plasma treatment, or left unmodified. The function of the molecular brush / felt material is to adjust the surface energy of the substrate to control the interfacial energy of two or more blocks of the block copolymer. This disclosure does not impose any particular limitation on the template modification method; methods well known to those skilled in the art can be used.

[0063] Guided self-assembly typically employs two methods: patterned epitaxy (geometric control) and chemical epitaxy (chemical induction). The former involves preparing guiding templates using photolithography, and then inducing guided self-assembly of the block copolymers under the geometric control of these templates. The latter involves chemically modifying the template surface, altering its polarity, affinity, surface tension, etc., to enable the self-assembly of the block copolymers to achieve guided self-assembly under the chemical induction of the template surface. For more information on these two self-assembly methods, please refer to Wang Qianqian et al., “Guided Self-Assembly of Block Copolymers,” Progress in Chemistry, 2017, 29(4): 435-442, the content of which is incorporated herein by reference.

[0064] Both of the above methods are applicable to this disclosure. Therefore, in the methods of this disclosure, the template may or may not be chemically modified.

[0065] In some embodiments, the method further includes preparing a first self-assembled block copolymer. In some embodiments, the method further includes preparing a second self-assembled block copolymer. The second self-assembled block copolymer may be the same as or different from the first self-assembled block copolymer. If the second self-assembled block copolymer differs from the first self-assembled block copolymer, a commercially available self-assembled block copolymer may be used. The second self-assembled block copolymer may or may not contain crosslinkable groups. If the second self-assembled block copolymer contains crosslinkable groups, these crosslinkable groups may be the same as or different from the cyclic crosslinkable groups defined in this disclosure.

[0066] Self-assembly occurs under certain conditions and is commonly referred to as annealing. Traditional annealing methods mainly include thermal annealing and solvent annealing. There are also some rapid annealing methods, such as microwave annealing, laser annealing, and solvent thermal annealing. For more information on annealing, please refer to Liu Yuling et al., “Rapid Self-Assembly Method for Block Copolymer Films,” Progress in Chemistry, 2022, 34(3), 609-615, the contents of which are incorporated herein by reference. This disclosure does not impose any particular restrictions on the annealing method.

[0067] This disclosure does not impose any particular limitation on the type of block copolymers, which may be AB-type diblock copolymers, ABA-type triblock copolymers, ABC-type triblock copolymers, AmBn-type heteroblock copolymers, bottle brush-type block copolymers, etc., which are well known to those skilled in the art.

[0068] Block copolymers comprise different blocks, each block typically comprising one or more identical repeating units arranged side-by-side along the polymer chain. Each block may include multiple repeating units of its corresponding type. For example, an AB block copolymer may have multiple type A repeating units in said (or each) A block and multiple type B repeating units in said (or each) B block.

[0069] Conventional self-assembled block copolymers are known in the art. Conventional self-assembled block copolymers are a class of block copolymers in which the compositions and / or structures of the blocks differ, and under certain conditions (e.g., through heat annealing or solvent treatment), phase separation occurs, forming regularly arranged domains. For example, in Figure 1In the density multiplication DSA step shown, the block copolymer of the coating forms a pattern of alternating red and blue portions. Different blocks in the self-assembled block copolymer have different properties; one block can be selectively removed while others remain, thereby forming a trench or hole pattern on the surface. Methods for removing blocks include plasma etching, solvent etching, developer etching, etc. Examples of self-assembled block copolymers include, but are not limited to, poly(styrene-b-methyl methacrylate), poly(styrene-b-methyl acrylate), poly(styrene-b-2-vinylpyridine), poly(styrene-b-butadiene), poly(styrene-b-ferrocene dimethylsilane), poly(styrene-b-ethylene oxide), poly(ethylene oxide-b-rubber matrix), poly(styrene-b-isoprene), poly(styrene-b-alkenyl aromatics), poly(isoprene-b-ethylene oxide), poly(styrene-b-(ethylene-propylene)), poly... (Ethylene oxide-β-caprolactone), poly(butadiene-β-ethylene oxide), poly(styrene-β-(meth)acrylate tert-butyl ester), poly(methyl methacrylate-β-methacrylate tert-butyl ester), poly(styrene-β-tetrahydrofuran), poly(styrene-β-isoprene-β-ethylene oxide), poly(styrene-β-dimethylsiloxane), poly(methyl methacrylate-β-dimethylsiloxane), poly(styrene-β-lactide), poly(styrene-β-glycolic acid), poly(ethylene oxide-β-propylene oxide), etc. The symbol "β" indicates "block". While these are examples of diblock copolymers, it should be understood that self-assembly can also be achieved using triblock copolymers, tetrablock copolymers, or other multiblock copolymers. It should be understood that known, developing, and future self-assembly block copolymers are applicable to this disclosure.

[0070] It should be understood that, although Figure 1 The block copolymer exhibits separation into a layered phase. Depending on the volume fraction of each block, the degree of polymerization of each block (i.e., the number of monomers within each block), the selected solvent, and surface interactions, the block copolymer can also form other phases during self-assembly, such as spherical phases (e.g., cubic) and columnar phases (e.g., quadrilateral or hexagonal). For the formation conditions of these different phases, see U.S. Patent US8501304B2, the contents of which are incorporated herein by reference. It is readily understood that the self-correcting guided self-assembly process of this disclosure is also applicable to these phases.

[0071] Surprisingly, in the "bottom-up" self-correcting guided self-assembly process disclosed herein, adjacent lower layers (e.g., the first layer) and upper layers (e.g., the second layer) can have different ordered phase domains. For example, the lower layer is layered (e.g., ...). Figure 1 As shown), the upper layer can be as follows: Figure 1The layered structure shown may not be layered; for example, it may be spherical or columnar. It is easy to understand that the next layer may also be spherical or columnar, and the previous layer may be any one of spherical, columnar, or layered structures. Those skilled in the art can obtain the same or different phases for each guided self-assembly layer by adjusting existing technology.

[0072] Although Figure 1 The diagram shows that the first layer pattern guides the second layer of self-assembling block copolymers to undergo 1:1 guided self-assembly (i.e., L0 is the same), but guided self-assembly in other ratios can also occur, such as 1:1 to 1:9, for example 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9 and any range therein.

[0073] Although Figure 1 The illustration shows two guided self-assemblies, but the self-correcting guided self-assembly of this disclosure can include more guided self-assemblies, such as three, four, or five guided self-assemblies. Therefore, in some exemplary embodiments, the self-assembly method for nanostructures of this disclosure further includes the step of performing a third guided self-assembly on a second nanostructure using a third self-assembly block copolymer or a third self-assembly block copolymer composition to obtain a third nanostructure. Similarly, the third self-assembly block copolymer can be the same as or different from either the first or second self-assembly block copolymer.

[0074] This disclosure does not impose any particular restrictions on the synthesis method of self-assembled block copolymer materials, and can be any living radical polymerization method known to those skilled in the art, such as ATRP, RAFT, and anionic polymerization.

[0075] For information on the basic principles, fundamental materials, methods of lithographic guidance patterns, and process flow of DSA lithography, please refer to Li Zili et al., “Sub-10 Nanometer Guided Self-Assembly and Deep Ultraviolet Hybrid Lithography Technology” (Laser & Optoelectronics Progress, May 2022, Vol. 59, No. 9, 0922027), the content of which is incorporated into this paper by reference.

[0076] The self-assembled block copolymers containing cyclic crosslinkable groups (e.g., the first self-assembled block copolymer) disclosed herein also possess self-assembly functionality, containing the cyclic crosslinkable groups defined herein. The crosslinkable groups can be located on one or more blocks of the block copolymer. The self-assembled block copolymer containing cyclic crosslinkable groups can be considered as being formed by introducing crosslinking groups into a conventional self-assembled block copolymer without crosslinkable groups. For example, if the self-assembled block copolymer without crosslinkable groups is represented as poly(AbB), then the self-assembled block copolymer containing cyclic crosslinkable groups can be obtained by introducing the cyclic crosslinkable groups G defined herein into the A block and / or the B block. In some exemplary embodiments, the cyclic crosslinkable groups G defined herein can be introduced into the monomer (M1) forming the A block and / or the monomer (M2) forming the B block, and the self-assembled block copolymer containing the cyclic crosslinkable groups G can be obtained by polymerization of the monomers according to the method for synthesizing block copolymers. There are no particular limitations on the method of introducing cyclic crosslinkable groups G onto monomers M1 and M2, and those skilled in the art can make selections based on existing technology. In some other exemplary embodiments, monomer M3, comprising the cyclic crosslinkable groups G as defined in this disclosure, may be additionally introduced. Monomer M3 and monomer M1 first form a random copolymer prepolymer, and then monomer M2 polymerizes in the presence of the prepolymer to form a block copolymer polymer (A'-bB), wherein A' is a block comprising repeating units formed by both monomers M1 and M3. In a preferred embodiment, monomer M3 is formed by introducing cyclic crosslinkable groups G into monomer M1. In other words, in this case, the block copolymer polymer (A'-bB) is equivalent to a block copolymer polymer (AbB) in which some repeating units of block A contain cyclic crosslinkable groups G. It is readily understood that monomer M3 may also first form a random copolymer prepolymer with monomer M2, and then monomer M1 polymerizes in the presence of the prepolymer to form a block copolymer polymer (Ab-B'), wherein B' is a block comprising repeating units formed by both monomers M2 and M3. In a preferred embodiment, monomer M3 is formed by introducing a cyclic crosslinkable group G into monomer M2. In other words, in this case, the block copolymer poly(Ab-B') corresponds to a partially repeating unit of block B in block copolymer poly(AbB) containing a cyclic crosslinkable group G. Where possible, monomer M3 can also be introduced into both block A and block B simultaneously to form block copolymer poly(A'-b-B'). In some exemplary embodiments, monomers M3 and M4 contain the same or different cyclic crosslinkable groups G, with monomer M3 introduced into block A (or block B) and monomer M4 introduced into block B (or block A). Similarly, monomer M3 can be formed by introducing a cyclic crosslinkable group G into monomer M1 (or monomer M2), and monomer M4 can be formed by introducing a cyclic crosslinkable group G into monomer M2 (or monomer M1).For triblock copolymers or copolymers with more blocks, crosslinking groups G can be introduced in the same manner. Methods for synthesizing random copolymers and block copolymers are known in the art.

[0077] Crosslinking groups can also be post-modified onto block copolymers through chemical modification.

[0078] The first self-assembled block copolymer may have the same or completely different block structure as the second self-assembled block copolymer. For example, if the second self-assembled block copolymer is poly(AbB), the first self-assembled block copolymer may be poly(A'-bC), where A' is a cyclic crosslinkable group as defined in this disclosure introduced into block A, and crosslinkable groups may or may not be introduced into C. The first self-assembled block copolymer may also be poly(DbE), where at least one of blocks D and / or E introduces a crosslinkable group, and D and E are different from A and B when no crosslinkable groups are introduced. The first self-assembled block copolymer may also have blocks with the same structure as the second self-assembled block copolymer, and the second self-assembled block copolymer may also contain crosslinkable groups. When the second self-assembled block copolymer contains a crosslinkable group, the crosslinkable group may be a cyclic crosslinkable group as defined in this disclosure (which may be the same as or different from the crosslinkable group of the first self-assembled block copolymer, or even in some embodiments, the second self-assembled block copolymer may be exactly the same as the first self-assembled block copolymer), or it may be a crosslinkable group other than a cyclic crosslinkable group as defined in this disclosure.

[0079] In some exemplary embodiments, the difference between the first self-assembled block copolymer and the second self-assembled block copolymer may be only that the first self-assembled block copolymer contains the cyclic crosslinkable groups defined in this disclosure, that is, if the crosslinkable group portion is removed or the portion containing the crosslinkable group is removed, the two are the same.

[0080] As an example, a self-assembled block copolymer containing the cyclic crosslinkable groups defined in this disclosure (e.g., a first self-assembled block copolymer) may contain or consist of two blocks represented by the following formula (XII):

[0081]

[0082] in Indicates the first segment, Indicates the second segment;

[0083] Self-assembled block copolymers (e.g., second self-assembled block copolymers) that do not contain the cyclic crosslinkable groups defined in this disclosure may contain or consist of two blocks represented by formula (XIII):

[0084]

[0085] in Indicates the first segment, This indicates the second segment.

[0086] In the formula, M1, M2, M3, and M4 represent repeating units capable of forming self-assembled block copolymers, any one of M1 and M2 is different from any one of M3 and M4, M1' and M2' represent repeating units capable of forming self-assembled block copolymers (one or both of M1' and M2' may contain crosslinkable groups different from the cyclic crosslinkable groups defined in this disclosure, or may not contain any crosslinkable groups), and at least one of G1 and G2 represents the cyclic crosslinkable groups defined in this disclosure (preferably both represent the cyclic crosslinkable groups defined in this disclosure). (a defined cyclic crosslinkable group), x1, x2, y1, y2 each represent an integer from 0 to 100 (e.g., 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 and any range thereof), m, n, m', n' each represent an integer from 1 to 100 (e.g., 1, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 and any range thereof), provided that x1+x2≥1, y1+y2≥1, and x2 and y2 are not both 0.

[0087] In some implementations, x2 / (x1+x2) = 0.01%-15% (e.g., 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15% and any range therebetween), and / or y2 / (y1+y2) = 0.01%-15% (e.g., 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15% and any range therebetween).

[0088] (x2+y2) / (x1+x2+y1+y2) = 0.01%-15% (e.g., 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, and any range between them).

[0089] In some implementations, x2 = 0, y2 ≠ 0.

[0090] In some implementations, x2 ≠ 0, y2 = 0.

[0091] In some implementations, x2≠0, y2≠0.

[0092] In some implementations, M1 and M2 are the same.

[0093] In some implementations, M3 and M4 are the same.

[0094] In some implementations, M1, M2, and M1' are the same.

[0095] In some implementations, M3, M4, and M2' are the same.

[0096] In some implementations, G1 and G2 are the same.

[0097] In some implementations, G1 and G2 are different.

[0098] The above situations can be combined.

[0099] In some exemplary embodiments, the self-assembled block copolymer (e.g., a first self-assembled block copolymer) comprising cyclic crosslinkable groups of this disclosure may comprise: (a) two or more repeating units and (b) cyclic crosslinkable groups selected from one or more of the group consisting of fused saturated alicyclic aryl, cyclic amino aryl, cyclic ether, and saturated alicyclic aryl. The two or more repeating units also constitute a self-assembled block copolymer, which may be selected from, for example, poly(styrene-b-methyl methacrylate), poly(styrene-b-methyl acrylate), poly(styrene-b-2-vinylpyridine), poly(styrene-b-butadiene), poly(styrene-b-ferrocene dimethylsilane), poly(styrene-b-ethylene oxide), poly(ethylene oxide-b-rubber matrix), poly(styrene-b-isoprene), poly(styrene-b-alkenyl aromatics), poly(isoprene-b-ethylene oxide), poly(styrene-b-(ethylene-propylene)) The poly(ethylene oxide-b-caprolactone), poly(butadiene-b-ethylene oxide), poly(styrene-b-(meth)acrylate tert-butyl ester), poly(methyl methacrylate-b-methacrylate tert-butyl ester), poly(styrene-b-tetrahydrofuran), poly(styrene-b-isoprene-b-ethylene oxide), poly(styrene-b-dimethylsiloxane), poly(methyl methacrylate-b-dimethylsiloxane), poly(styrene-b-lactide), poly(styrene-b-glycolic acid), and poly(ethylene oxide-b-propylene oxide). The cyclic crosslinkable group is located on one or more repeating units of the two or more repeating units.

[0100] In some exemplary embodiments, self-assembled block copolymers (e.g., second self-assembled block copolymers) that do not contain the cyclic crosslinkable groups defined in this disclosure may be selected from, for example, poly(styrene-b-methyl methacrylate), poly(styrene-b-methyl acrylate), poly(styrene-b-2-vinylpyridine), poly(styrene-b-butadiene), poly(styrene-b-ferrocene dimethylsilane), poly(styrene-b-ethylene oxide), poly(ethylene oxide-b-rubber matrix), poly(styrene-b-isoprene), poly(styrene-b-alkenyl aromatics), poly(isoprene-b-ethylene oxide), poly(styrene-b-rubber matrix), poly(styrene-b-isoprene), poly(styrene-b-alkenyl aromatics), poly(isoprene-b-ethylene oxide), poly(styrene-b-isoprene ... Any one or more of the following: (styrene-b-(ethylene-propylene)), poly(ethylene oxide-b-caprolactone), poly(butadiene-b-ethylene oxide), poly(styrene-b-(meth)acrylate tert-butyl ester), poly(methyl methacrylate-b-methacrylate tert-butyl ester), poly(styrene-b-tetrahydrofuran), poly(styrene-b-isoprene-b-ethylene oxide), poly(styrene-b-dimethylsiloxane), poly(methyl methacrylate-b-dimethylsiloxane), poly(styrene-b-lactide), poly(styrene-b-ethylene lactide), and poly(ethylene oxide-b-propylene oxide).

[0101] In the guided self-assembly method for nanostructures disclosed herein, at least one guided self-assembly (e.g., the first guided self-assembly) utilizes a self-assembly block copolymer (e.g., the first self-assembly block copolymer) containing cyclic crosslinkable groups as defined in this disclosure. Other guided self-assemblies (e.g., the second, third, fourth, etc.) may utilize self-assembly block copolymers containing cyclic crosslinkable groups as defined in this disclosure, or they may utilize self-assembly block copolymers that do not contain cyclic crosslinkable groups as defined in this disclosure (e.g., the second, third, fourth, etc.).

[0102] The cyclic crosslinkable group disclosed herein for self-correcting guided self-assembly can be a fused saturated alicyclic aryl group, a cyclic amino aryl group, a cyclic ether group, or a saturated alicyclic aryl group.

[0103] As used herein, the term "fused saturated alicyclic aryl" refers to a saturated alicyclic aryl group fused with an aryl group, both sharing two carbon atoms, wherein the linker site of the crosslinkable group in a self-assembled block copolymer is on the aryl group. In a more specific embodiment, the fused saturated alicyclic aryl group is formed by substituted or unsubstituted alkylene groups connected at both ends to two adjacent carbon atoms of the aryl group; for example, a substituted or unsubstituted alkylene group may be represented as -(CR... A R B ) m -, where R A and R BEach group is independently selected from one or more of hydrogen, (C1-C4)alkyl, carboxyl, amino, nitro, hydroxyl, cyano, and amino, preferably hydrogen, (C1-C4)alkyl, or hydroxyl; m is an integer from 1 to 5; the aryl group can be a substituted or unsubstituted (C6-C30) aryl group, such as phenyl, naphthyl, anthracene, phenanthrene, etc., and the substituents on the substituted (C6-C30) aryl group can be one or more of (C1-C4)alkyl, carboxyl, amino, and nitro, preferably (C1-C4)alkyl.

[0104] As used herein, the term "saturated alicyclic aryl" refers to an aryl group with a saturated alicyclic aryl group attached to it, both sharing a carbon atom, wherein the linker site of the crosslinkable group in a self-assembled block copolymer is on the aryl group. In a more specific embodiment, the saturated alicyclic aryl group is formed by attaching a substituted or unsubstituted cycloalkyl group to a carbon atom of the aryl group, the cycloalkyl group being (C3-C4)cycloalkyl, such as cyclopropyl or cyclobutyl. Each substituent on the cycloalkyl group is independently selected from one or more of (C1-C4)alkyl, carboxyl, amino, nitro, hydroxy, hydroxy-(C1-C4)alkyl, cyano, and amino groups, preferably (C1-C4)alkyl or hydroxy-(C1-C4)alkyl. The hydroxy-(C1-C4)alkyl group can be, for example, hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxybutyl, and their isomers. The aryl group can be a substituted or unsubstituted (C6-C30) aryl group, such as phenyl, naphthyl, anthracene, phenanthrene, etc. The substituents on the substituted (C6-C30) aryl group can be one or more of (C1-C4) alkyl, carboxyl, amino, and nitro groups, preferably (C1-C4) alkyl.

[0105] As used herein, the term "cyclic aminoaryl" indicates that the cyclic amine is attached to an aryl group via a nitrogen atom (N), wherein the linker site of the crosslinkable group in a self-assembled block copolymer is on the aryl group. In a more specific embodiment, the cyclic amine is formed by substituted or unsubstituted alkylene groups connected to nitrogen atoms at both ends, for example, substituted or unsubstituted alkylene groups may be represented as -(CR C R D ) n -, where R C and R D Each group is independently selected from one or more of hydrogen, (C1-C4)alkyl, carboxyl, amino, nitro, hydroxyl, cyano, and amino, preferably hydrogen or (C1-C4)alkyl; n is an integer from 2 to 5; the aryl group can be a substituted or unsubstituted (C6-C30)aryl group, such as phenyl, naphthyl, anthracene, phenanthrene, etc., and the substituents on the substituted (C6-C30)aryl group can be one or more of (C1-C4)alkyl, carboxyl, amino, and nitro, preferably (C1-C4)alkyl.

[0106] In some embodiments, the fused saturated alicyclic hydrocarbon aryl group has the general formula (I):

[0107]

[0108] In some embodiments, the cyclic aminoaryl group has the general formula (II):

[0109]

[0110] In some embodiments, the cyclic ether group has the general formula (III):

[0111]

[0112] In some embodiments, the cyclic ether group has the general formula (IV):

[0113]

[0114] This represents the linking site of crosslinkable groups in a self-assembled block copolymer. In formula (I), It can be located on any one of the four usable carbon atoms on the benzene ring. In formula (II), It can be located on any one of the five usable carbon atoms on the benzene ring. Each R1 and each R2 is independently selected from one or more of (C1-C4)alkyl, carboxyl, amino (-NH2), nitro, hydroxyl, cyano, and amino (amino refers to (-NR2) herein, and each R is independently a C1-C4)alkyl), preferably (C1-C4)alkyl. In this document, the (C1-C4)alkyl comprises methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tert-butyl. Each R A Each R B Each R C and each R D Each R3 is independently selected from one or more of hydrogen, (C1-C4)alkyl, carboxyl, amino, nitro, hydroxyl, cyano, and amino groups, preferably hydrogen, (C1-C4)alkyl, or hydroxyl. Each R3, each R... E Each R F Each R G and each R HEach phenyl group is independently selected from one or more of hydrogen, (C1-C4)alkyl, substituted or unsubstituted phenyl groups, preferably hydrogen or (C1-C4)alkyl. The substituted phenyl group comprises 1 to 5 substituents, each substituent independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl. a is an integer from 0 to 3, for example, the range of 0, 1, 2, 3, and any two of them. b is an integer from 0 to 4, for example, the range of 0, 1, 2, 3, 4, and any two of them. m is an integer from 1 to 5, for example, the range of 1, 2, 3, 4, 5, and any two of them. n is an integer from 2 to 5, for example, the range of 2, 3, 4, 5, and any two of them. p and q are each independently an integer from 0 to 4, for example, the range of 0, 1, 2, 3, 4, and any two of them. p+q is an integer from 1 to 4, for example, the range of 1, 2, 3, 4, and any two of them. Ph represents a substituted or unsubstituted phenylene group; Cy represents a substituted or unsubstituted (C3-C4) saturated alicyclic hydrocarbon group. The substituent on the substituted phenylene group can be one or more of (C1-C4) alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups, preferably (C1-C4) alkyl. The (C3-C4) saturated alicyclic hydrocarbon group can be cyclopropyl or cyclobutyl. Each substituent on the substituted (C3-C4) saturated alicyclic hydrocarbon group is independently selected from one or more of (C1-C4) alkyl, carboxyl, amino, nitro, hydroxy, hydroxy-(C1-C4) alkyl, cyano, and amino groups, preferably (C1-C4) alkyl or hydroxy-(C1-C4) alkyl.

[0115] As a more specific embodiment, the crosslinkable group is selected from any one of the following formulas (V) to (XI):

[0116]

[0117]

[0118] In the above formulas, R1, R2, R3, R E R F R G R H The definitions of a and b are the same as above; each R4, each R5 and each R6, each R7, each R8, each R9, each R 10Each is independently selected from one or more of (C1-C4) alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups, preferably (C1-C4) alkyl; c, d, f, and h are each independently an integer from 0 to 4, for example, 0, 1, 2, 3, 4, and any combination thereof; e is an integer from 0 to 6, for example, 0, 1, 2, 3, 4, 5, 6, and any combination thereof; g is an integer from 0 to 5, for example, 0, 1, 2, 3, 4, 5, and any combination thereof; i is an integer from 0 to 7, for example, 0, 1, 2, 3, 4, 5, 6, 7, and any combination thereof.

[0119] In some more specific embodiments, the crosslinkable group is selected from the group consisting of:

[0120]

[0121] The self-assembled block copolymer compositions described in this disclosure comprise the self-assembled block copolymers (e.g., first self-assembled block copolymers) containing cyclic crosslinkable groups as described in this disclosure. The compositions may also contain a solvent. The solvent may be any solvent suitable for formulating the self-assembled block copolymers containing crosslinkable groups as coated (e.g., spin-coating) liquids (e.g., solutions). Suitable solvents include, but are not limited to, toluene, propylene glycol methyl ether acetate (PGMEA), etc. The self-assembled block copolymer compositions described in this disclosure may also contain suitable additives as needed, including but not limited to small molecule compounds, homopolymers, block copolymers, etc.

[0122] In such Figure 1 As shown, after the formation of a second (or more) block copolymer self-assembled layer by guided self-assembly, steps such as removing at least a portion of the block copolymer and etching can be performed. These steps are known and can be found in Boyce S. Chang et al., “Sequential Brush Grafting for Chemically and Dimensionally Tolerant Directed Self-Assembly of Block Copolymers”, ACS Appl. Mater. Interfaces, 2023, 15, 2020-2029, the contents of which are incorporated herein by reference.

[0123] The present invention will be described below by way of specific embodiments. It should be understood that these embodiments are merely illustrative and are not intended to limit the scope of the invention. The methods, reagents, and materials used in the embodiments are conventional methods, reagents, and materials in the art, unless otherwise stated. The raw material compounds in the embodiments are all commercially available.

[0124] Example

[0125] 1)Synthetic materials

[0126] Example 1

[0127] First, a block copolymer PS-bP(MMA-r-Oxe) was synthesized using atom transfer radical polymerization (ATRP) as the first crosslinkable layer in the srDSA process. Using commercially available ethyl α-bromophenylacetate (EBPA, CAS: 2882-19-1) as an initiator, and methyl methacrylate (MMA, CAS: 80-62-6) and oxobutane methacrylate (Oxe, CAS: 37674-57-0) as monomers, the P(MMA-r-Oxe)-Br macromolecular initiator was first synthesized. 3.0 g CuBr, 1.0 g CuBr2, 750 g MMA, 28.2 g Oxe, 7.3 g EBPA, and 5.0 g N,N,N',N',N”-pentamethyldiethylenetriamine (PMDETA) were dissolved in 500 g anisole. After deoxygenation by purging with nitrogen for 30 minutes, the mixture was stirred at 70 °C for a certain time, cooled, diluted with 200 mL tetrahydrofuran, and passed through a neutral alumina column to remove copper salts. The solid was precipitated in methanol to obtain a white solid, which was filtered and dried under vacuum to obtain P(MMA-r-Oxe)-Br. Its molecular weight was characterized by gel permeation chromatography (GPC, Waters), with a number-average molecular weight of 26 kJ and a molecular weight distribution (PDI) of 1.04. The molecular weight was further characterized by proton nuclear magnetic resonance spectroscopy (NMR). 1 ¹H NMR (Bruker 500) calculated the molar fraction of Oxe in the copolymer to be 2 mol%.

[0128] Using the synthesized P(MMA-r-Oxe)-Br as a macromolecular initiator, styrene polymerization was further initiated to prepare PS-bP(MMA-r-Oxe) block copolymer. 20g P(MMA-r-Oxe)-Br, 107g styrene, 250mg CuBr, and 0.7g PMDETA were fully dissolved. After purging with nitrogen for 30 minutes to remove oxygen, the mixture was stirred at 100℃ for a certain period, cooled, and allowed to settle into methanol to obtain a white solid. The solid was filtered, vacuum dried, and PS-bP(MMA-r-Oxe) was obtained. Its molecular weight was characterized by gel permeation chromatography (GPC, Waters), with a number average molecular weight of 59kJ and a molecular weight distribution (PDI) of 1.06. Nuclear magnetic resonance (NMR) spectroscopy (NMR) was used to further characterize the solid. 1 The volume fraction (Φ) of PS in the block copolymer was calculated using HNMR (Bruker 500). PS The percentage is 56.3%. PS-bP (MMA-r-Oxe) is a layered phase material with a phase separation period of 27.8 nm.

[0129] Next, ATRP was used to synthesize the block copolymer PS-b-PMMA as the second-layer block copolymer in the srDSA process. The synthesis method is the same as that of PS-bP (MMA-r-Oxe), except that in the synthesis of the PMMA macromolecular initiator, only MMA was used as the monomer, and the ratio of initiator to monomer and the reaction time were changed to obtain PS-b-PMMA with a number-average molecular weight of 60kJ and a molecular weight distribution of 1.05. PS The percentage is 48.2%. PS-b-PMMA is a layered phase material with a phase separation period of 28 nm.

[0130]

[0131] Example 2

[0132] First, a macromolecular initiator (P(Sr-4VBCB)-OH) for the hydroxyl-terminated polystyrene-poly(4-vinylbenzocyclobutene) random copolymer was synthesized. Using commercially available ethylene glycol bromoisobutyrate (HEBIB, CAS: 248603-11-4) as an initiator, the hydroxyl-terminated P(Sr-4VBCB)-OH was synthesized via the ATRP method. 500 g of styrene, 5 g of 4-vinylbenzocyclobutene (4VBCB, CAS: 99717-87-0), 0.95 g of cuprous bromide, and 0.35 g of PMDETA were thoroughly stirred and dissolved. The mixture was then purged with nitrogen for 30 minutes to remove oxygen, reacted at 110 °C for 4.5 hours, cooled, diluted with 100 mL of toluene, and passed through a neutral alumina column to remove the copper salt. The solid precipitated into methanol was filtered, dissolved in tetrahydrofuran, and precipitated into methanol. The mixture was then filtered again and dried under vacuum to obtain P(Sr-4VBCB)-OH. Its molecular weight was characterized by gel permeation chromatography (GPC, Waters), with a number-average molecular weight of 27.8 kJ and a PDI of 1.10. The molecular weight was further characterized by proton nuclear magnetic resonance spectroscopy (NMR). 1 ¹H NMR (Bruker 500) calculated the molar fraction of 4VBCB in the copolymer to be 0.8 mol%.

[0133] Polystyrene-poly(4-vinylbenzocyclobutene)-b-polylactide block copolymer (P(Sr-4VBCB)-b-PLA) was synthesized by ring-opening polymerization. 20 g of P(Sr-4VBCB)-OH was weighed and reacted three times with anhydrous toluene at 120 °C. 30 g of lactide (LA) was added to a glove box, and the mixture was purged with nitrogen three times. 300 mL of toluene and 20 mL of 5 mg / L stannous octoate solution were added, and the reaction was carried out at 120 °C for a certain time. After cooling, 150 mL of chloroform was added for dilution, and the mixture was precipitated in methanol. The mixture was filtered and dried under vacuum to obtain P(Sr-4VBCB)-b-PLA. The molecular weight of PLA was characterized by 1H NMR spectroscopy, with a number-average molecular weight of 11.3kJ. The PDI of P(Sr-4VBCB)-b-PLA was 1.15. The volume fraction of P(Sr-4VBCB) in the block copolymer was calculated to be 74.5% based on density. P(Sr-4VBCB)-b-PLA is a columnar phase material with a phase separation period of 34.3 nm.

[0134] Next, the block copolymer PS-b-PLA was synthesized using the same synthesis process as the second-layer block copolymer in the srDSA process. The synthesis method was the same as that of P(Sr-4VBCB)-b-PLA, except that St was used as the monomer only when synthesizing the P(Sr-4VBCB) macromolecular initiator. By changing the ratio of initiator to monomer and the reaction time, PS-b-PLA was obtained. The number-average molecular weight of the PS segment in PS-b-PLA was 19.3k, the number-average molecular weight of the PLA segment was 56.3k, the PDI of PS-b-PLA was 1.14, the volume fraction of PS in PS-b-PLA was 74.8%, and PS-b-PLA was a columnar phase material with a phase separation period of 34.2 nm.

[0135]

[0136] Example 3

[0137] First, a macromolecular initiator (P(4ClSt-r-CEB)) was synthesized via the RAFT method using 4-ClSt (CAS: 1073-67-2) and 1-cyclopropyl-4-vinylbenzene (CEB, CAS: 19824-39-6) as monomers. 125 g of 4-ClSt, 15 g of CEB, 647 mg of CPCTTPA, and 10.3 mg of AIBN were added to a reaction flask, stirred thoroughly to dissolve, and purged with nitrogen for 30 minutes to remove oxygen. The reaction was carried out at 80 °C for 24 hours. After cooling, the solid precipitated into methanol, filtered, and dried under vacuum to obtain P(4ClSt-r-CEB). Its molecular weight was characterized by gel permeation chromatography (GPC, Waters), with a number-average molecular weight of 15.8 kJ and a PDI of 1.12. The molecular weight was further characterized by proton nuclear magnetic resonance (NMR) spectroscopy.1 ¹H NMR (Bruker 500) calculated the molar fraction of CEB in the copolymer to be 10.3 mol%.

[0138] Using the synthesized P(4ClSt-r-CEB) as a macromolecular initiator, methyl acrylate (MA) polymerization was further initiated to prepare P(4ClSt-r-CEB)-PMA block copolymer. 16g of P(4ClSt-r-CEB), 93g of MA, and 12mg of AIBN were fully dissolved, and after purging with nitrogen for 30 minutes to remove oxygen, the mixture was stirred at 80°C for 40 minutes. After cooling, the solid precipitated into methanol, which was then filtered and vacuum dried to obtain P(4ClSt-r-CEB)-PMA. The molecular weight was characterized by gel permeation chromatography (GPC, Waters). The number-average molecular weight of the PMA segment was 14.1kJ, and the molecular weight distribution (PDI) was 1.10. The volume fraction of P4ClSt in this block copolymer was 51.2%, and P(4ClSt-r-CEB)-PMA was a layered phase material with a period of 35.2nm.

[0139] Next, the block copolymer PS-b-PMMA was synthesized using ATRP polymerization as the second-layer block copolymer in the srDSA process. The synthesis method was the same as that in Example 1, except that the ratio of initiator to monomer and the reaction time were changed. The resulting PS-b-PMMA had a number-average molecular weight of 72.5kJ, a molecular weight distribution of 1.17, and a Ф... PS The percentage is 87.6%. This PS-b-PMMA is a spherical phase material with a phase separation period of 34.8 nm.

[0140]

[0141] Example 4

[0142] First, PMMA-Br macromolecular initiator was synthesized from MMA as monomer via ATRP. 3.0 g CuBr, 1.0 g CuBr2, 520 g MMA, 7.3 g EBPA, and 5.0 g N,N,N',N',N”-pentamethyldiethylenetriamine (PMDETA) were dissolved in 500 g anisole. After deoxygenation by purging with nitrogen for 30 minutes, the mixture was stirred at 70 °C for a certain time, cooled, diluted with 200 mL tetrahydrofuran, and passed through a neutral alumina column to remove copper salts. The solid was precipitated into methanol to obtain a white solid, which was filtered and dried under vacuum to obtain PMMA-Br. Its molecular weight was characterized by gel permeation chromatography (GPC, Waters), showing a number-average molecular weight of 17.2 kJ and a molecular weight distribution (PDI) of 1.04.

[0143] Using the synthesized PMMA-Br as a macromolecular initiator, the copolymerization of p-methylstyrene (4MeSt, CAS: 622-97-9) and 3-vinylbenzocyclobutene (3VBCB, CAS: 135409-92-6) was further initiated to prepare P(4MeSt-r-3VBCB)-b-PMMA block copolymer. 15g PMMA-Br, 130g 4MeSt, 1g 3VBCB, 300mg CuBr, and 0.8g PMDETA were fully dissolved, and after purging with nitrogen for 30 minutes to remove oxygen, the mixture was stirred at 100℃ for a certain time. After cooling, the solid precipitated into methanol, which was filtered and dried under vacuum to obtain P(4MeSt-r-3VBCB)-b-PMMA. Its molecular weight was characterized by gel permeation chromatography (GPC, Waters), with a number-average molecular weight of 83kJ and a molecular weight distribution (PDI) of 1.08. The molecular weight was further characterized by proton nuclear magnetic resonance spectroscopy (NMR). 1 The volume fraction (Φ) of PS in the block copolymer was calculated using ¹H NMR (Bruker 500). PS The percentage is 83.2%. P(4MeSt-r-3VBCB)-b-PMMA is a spherical phase material with a phase separation period of 29.8 nm.

[0144] Next, the block copolymer P4MeSt-b-PMA was synthesized via ATRP polymerization as the second-layer block copolymer in the srDSA process. The obtained P4MeSt-b-PMA had a number-average molecular weight of 63.2 kJ, a molecular weight distribution of 1.12, and a Ф... PS The percentage is 74.3%. This P4MeSt-b-PMA is a columnar phase material with a phase separation period of 30.2 nm.

[0145]

[0146] Example 5-22

[0147] Following the synthesis methods of Examples 1-4, by changing the monomer type, the ratio of initiator to monomer, the proportion of monomers containing crosslinkable groups, the reaction time, and the reaction temperature, a series of first-layer block copolymers containing different crosslinkable groups, of different types, with different molecular weights, and with different volume fractions can be obtained. Details are shown in Table 1 below.

[0148]

[0149]

[0150]

[0151]

[0152] The first-layer block copolymer in Table 1 is a self-assembled block copolymer containing cyclic crosslinkable groups, formed by monomer 1, monomer 2 and a monomer containing crosslinkable groups.

[0153] 2) Template preparation

[0154] PMMA photoresist was spin-coated onto a cross-linked polystyrene-modified substrate. The PMMA photoresist pattern was obtained by electron beam exposure and development. Then, a line pattern with a period of 84 nm was obtained by plasma treatment as a guide template.

[0155] 3) Backfilling with molecular felt

[0156] Taking random copolymer molecular felt as an example, a PS-r-PMMA-r-PGMA random copolymer solution is spin-coated onto the template surface (PGMA: polyglycidyl methacrylate), and then heated and annealed under vacuum conditions to obtain a template modified with molecular felt.

[0157] 4) Density-multiplying DSA (first cross-linked layer)

[0158] The PS-bP(MMA-r-Oxe) block copolymer solution synthesized in Example 1 was spin-coated onto the surface of the molecular felt modified in step 3), and then annealed under vacuum conditions (temperature range 180-300℃) to obtain a cross-linked nanostructure (surface structure as shown in Figure 3). Figure 3 (As shown).

[0159] 5) 1:1 DSA (Second Layer Assembly)

[0160] The PS-b-PMMA block copolymer solution synthesized in Example 1 was spin-coated onto the cross-linked and cured nanostructure surface in step 4), and then annealed under vacuum conditions (temperature range 180-300℃) to obtain a defect-free nanostructure (surface structure as shown in Figure 4). Figure 4 (As shown).

[0161] Example 1 illustrates the process of assembling layered phase materials using a line template with two DSA-guided steps, shown in the cross-sectional diagram. Figure 2 .

[0162] As a control, direct 3x density-multiply guided self-assembly using PS-b-PMMA on a line template yielded nanostructures such as... Figure 5 As shown.

[0163] from Figure 5 It can be seen that the nanostructure obtained using self-assembled block copolymers without the cyclic crosslinkable groups described in this disclosure exhibits large-area dislocation / fingerprint defects, with an LER(3σ) of 2.62 and an LWR(3σ) of 1.95 at uniform lines. In contrast, as Figure 3As shown, the nanostructure obtained using the self-assembled block copolymer containing the cyclic crosslinkable groups described in this disclosure is almost defect-free. Using this nanostructure as a chemically guided template, a second guided self-assembly is performed, resulting in the following nanostructure: Figure 4 As shown, the applicant used SEM to capture images with a total area of ​​0.11 mm². 2 No defects were found, and the estimated number of defects is at least < 1,000 / cm. 2 . Figure 4 The nanostructure shown has an LER(3σ) of 1.93 and an LWR(3σ) of 1.63, which is consistent with... Figure 5 The nanostructure shown is significantly smaller in size compared to its predecessor. The LER and LWR values ​​in this application were measured using MATLAB software.

[0164] Following the processing steps 2)-3), guide templates of different types and cycles were prepared. Then, using the process 4), DSA was performed with the materials from Examples 2-22. The specific parameters are shown in Table 2 below.

[0165] Table 2 Initial template type, cycle, and first-layer block copolymer

[0166]

[0167]

[0168] Experiments show that the self-assembled block copolymers containing cyclic crosslinkable groups disclosed herein (such as the first-layer block copolymers prepared in Examples 2-22 as shown in Table 2) are suitable for different types and periods of templates and can undergo different density multiplications, as can be seen from the initial template period in Table 2 and the phase separation period of the first-layer block copolymers in Table 1 (the phase separation periods of Examples 2-4 are described in the corresponding example descriptions). Similar to the results of Example 1, nanostructures with far fewer defects than those of self-assembled block copolymers without cyclic crosslinkable groups can be obtained through self-assembly. Further guided self-assembly can be performed on these nanostructures, resulting in nanostructures with not only extremely few defects but also very small LER and LWR.

[0169] The applicant has demonstrated through experiments that the method disclosed herein is not limited to guiding the assembly of layered phase materials (such as columnar phase materials in Example 2), and that each layer can be guided by different types of materials (layered phase + columnar phase in Example 3; spherical phase + columnar phase in Example 4). Figure 6 The diagram shows a cross-sectional view of Example 4, in which a four-sided lattice template is used to first guide the assembly of spherical phase materials with a 9-fold density multiplication DSA, and then guide the assembly of columnar phase materials.

[0170] It is not difficult to understand that, based on the technical principles of this disclosure, the method of this disclosure is not limited to two layers, but can perform multi-layer guidance.

[0171] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0172] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A guided self-assembly method for nanostructures, characterized in that, The method includes: The first nanostructure is obtained by first guided self-assembly using a first self-assembly block copolymer and cross-linking. A second self-assembly is performed on the first nanostructure using a second self-assembly block copolymer to obtain a second nanostructure. The first self-assembled block copolymer comprises cyclic crosslinkable groups, wherein the cyclic crosslinkable groups are selected from one or more of the following: fused saturated alicyclic aryl, cyclic amino aryl, cyclic ether, and saturated alicyclic aryl. The fused saturated alicyclic aryl group has the general formula (I): （I）； The cyclic aminoaryl group has the general formula (II): (II); The cyclic ether group has the general formula (III): (III); The saturated alicyclic hydrocarbon aryl group has the general formula (IV): —Ph-Cy (IV) in Indicates the linking site of crosslinkable groups in a self-assembled block copolymer; each R1 and each R2 is independently selected from C1-C4 alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups; each R A Each R B Each R C and each R D Each is independently selected from hydrogen, C1-C4 alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups; R3, each R E Each R F Each R G and each R H Each is independently selected from hydrogen, C1-C4 alkyl and substituted or unsubstituted phenyl; a is an integer from 0 to 3; b is an integer from 0 to 4; m is an integer from 1 to 5; n is an integer from 2 to 5; p and q are each independently integers from 0 to 4, and p+q is an integer from 1 to 4; Ph represents a substituted or unsubstituted phenylene; Cy represents a substituted or unsubstituted C3-C4 saturated alicyclic hydrocarbon group.

2. The method according to claim 1, characterized in that, Each R1 and each R2 is independently a C1-C4 alkyl group.

3. The method according to claim 1, characterized in that, Each R A Each R B Each R C and each R D Each is independently hydrogen, C1-C4 alkyl, or hydroxyl.

4. The method according to claim 1, characterized in that, R3, each R E Each R F Each R G and each R H Each is independently hydrogen or C1-C4 alkyl.

5. The method according to claim 1, characterized in that, Each substituent of the substituted phenyl group is independently selected from C1-C4 alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups; and / or Each substituent of the substituted phenylene group is independently selected from C1-C4 alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups; and / or Each substituent of the substituted C3-C4 saturated alicyclic hydrocarbon group is independently selected from C1-C4 alkyl, carboxyl, amino, nitro, hydroxy, hydroxy-C1-C4 alkyl, cyano, and amino groups.

6. The method according to claim 5, characterized in that, Each substituent of the substituted C3-C4 saturated alicyclic hydrocarbon group is independently a C1-C4 alkyl or hydroxy-C1-C4 alkyl group.

7. The method according to claim 1, characterized in that, The cyclic crosslinkable group is selected from any one or more of formulas (V) to (XI): （V）； (WE); (VII) (VIII); (IX), （X）， (XI), Where R1, R2, R3, R E R F R G R H The definitions of a and b are the same as in claim 1; each R4, each R5, each R6, each R7, each R8, each R9, and each R 10 Each is independently selected from one or more of C1-C4 alkyl, carboxyl, amino, nitro, hydroxy, cyano, and amino groups; c, d, f, and h are each independently integers from 0 to 4, e is an integer from 0 to 6, g is an integer from 0 to 5, and i is an integer from 0 to 7.

8. The method according to claim 7, characterized in that, Each R4, each R5, each R6, each R7, each R8, each R9, and each R 10 Each is independently a C1-C4 alkyl group.

9. The method according to claim 1, characterized in that, The cyclic crosslinkable group is selected from any one or more of the following group: ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； ； 。

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