Resist composition, laminate, and pattern forming method

Abstract

The invention relates to a resist composition, a laminate, and a pattern forming method. The present invention addresses the problem of providing: a resist composition having excellent sensitivity and resolution in optical lithography using high-energy rays, particularly electron beam (EB) lithography and EUV lithography; and a pattern forming method using the resist composition. The resist composition is characterized by containing a hypervalent iodine compound represented by formula (1), a carboxyl group-containing compound, and a solvent. In the formula, when m is 0, n is an integer of 0-4, when m is 1, n is an integer of 0-6, and when m is 2, n is an integer of 0-8. R1, R2 and R3 are halogen atoms or alkyl with 1-10 carbon atoms. And R4 represents a halogen atom or a hydrocarbon group having 1-40 carbon atoms. And R5 represents a carbonyl group or a C1-10 alkylene group. I and R5 are bonded to adjacent carbon atoms on an aromatic ring.

Description

Technical Field

[0001] This invention relates to a resist composition, a laminate, and a method for forming a pattern using the aforementioned resist composition. Background Technology

[0002] With the expansion of the IoT market, there is a growing demand for high integration, high speed, and low power consumption in LSI (Light Silica) technology, and the miniaturization of patterning is also progressing rapidly. In particular, logic devices are leading the way in miniaturization. Regarding the most advanced miniaturization technologies, mass production of 10nm node devices using ArF immersion lithography with dual, triple, and quadruple patterning is already underway. Furthermore, research is progressing on next-generation 7nm node devices using extreme ultraviolet (EUV) lithography with a wavelength of 13.5nm.

[0003] As miniaturization progresses, image blurring caused by acid diffusion has become a problem (Non-Patent Literature 1). To ensure the resolution of fine patterns with a processing size of less than 45 nm, it has been proposed that not only is the improvement of dissolution contrast, as previously advocated, important, but also the control of acid diffusion is crucial (Non-Patent Literature 2). However, since chemically amplified resist compositions improve sensitivity and contrast through acid diffusion, if acid diffusion is suppressed to the limit by lowering the post-exposure baking (PEB) temperature or shortening the PEB time, sensitivity and contrast will be significantly reduced.

[0004] Adding acid-generating agents that produce bulky acids is effective in suppressing acid diffusion. Therefore, it has been proposed to use onium salts of polymerizable olefins as acid-generating agents in polymer copolymerization. However, considering acid diffusion, in the patterning of resist films with dimensions smaller than 16 nm, it is believed that chemically amplified resist compositions are no longer suitable for patterning, and the development of non-chemically amplified resist compositions is desired.

[0005] Materials used in non-chemically amplified resist compositions include polymethyl methacrylate (PMMA). PMMA is a positive resist material whose solubility in organic solvent developers is improved by breaking down the main chain and reducing the molecular weight through EUV irradiation.

[0006] Hydrosilsesquioxane (HSQ) is a negative resist material that is insoluble in alkaline developers, resulting from the crosslinking reaction of silanols produced by EUV irradiation. Chlorinated calixarnes also function as negative resist materials. These negative resist materials, due to their small molecular size before crosslinking and the absence of blurring caused by acid diffusion, can be used as pattern transfer materials with low edge roughness and very high resolution, showcasing the resolving limits of exposure devices. However, these materials have insufficient sensitivity and require further improvement.

[0007] One of the main reasons hindering material development for EUV lithography applications is the low photon count in EUV exposure. EUV energy is significantly higher than ArF excimer lasers, and the photon count in EUV exposure is only one-fourteenth that of ArF exposure. Furthermore, the size of patterns formed by EUV exposure is less than half that of ArF exposure. Therefore, EUV exposure is susceptible to variations in photon count. These variations in photon count in extremely short wavelength emission regions constitute shot noise, a physical phenomenon that cannot be eliminated. Thus, so-called stochastics are a concern. While the effects of shot noise cannot be eliminated, we will discuss how to reduce them. Due to shot noise, not only do dimensional uniformity (CDU) and linewidth roughness (LWR) increase, but there is also a one in a million chance of observing hole blockage. Hole blockage leads to poor conductivity and transistor malfunction, thus negatively impacting overall device performance. When considering practical sensitivity, resist compositions with PMMA and HSQ as the main components are greatly affected by randomness and cannot achieve the desired resolution performance.

[0008] As a method to reduce the impact of shot noise from the resist aspect, introducing elements with high absorption of EUV light has attracted attention. Patent Document 1 proposes a chemically amplified resist composition containing iodine atoms with high absorption of EUV light. However, as mentioned above, chemically amplified resist compositions cannot achieve excellent resolution performance in EUV lithography with increasingly smaller processing dimensions in the future.

[0009] Patent Document 2 proposes a negative resist composition using tin compounds. This composition uses tin, which has high absorption under EUV light, as the main component, thus improving randomness and enabling high sensitivity and high resolution. However, such metal resists suffer from many problems, including insufficient solubility in resist solvents, storage stability, and defects caused by etching residues.

[0010] In contrast, Patent Document 3 proposes a positive resist composition using a high-valent iodine compound. It contains iodine, which has high absorption for EUV light, thus improving randomness similar to metal resists and achieving high sensitivity and high resolution. Furthermore, since it consists only of organic molecules, it addresses the problems of metal resists, namely developer solubility and defects caused by residue. However, the performance of this resist material remains unsatisfactory, and there is a need to develop resist materials useful for forming finer patterns.

[0011] Existing technical documents

[0012] Patent documents

[0013] [Patent Document 1] Japanese Patent Application Publication No. 2018-005224

[0014] [Patent Document 2] Japanese Patent Publication No. 2021-503482

[0015] [Patent Document 3] Japanese Patent Application Publication No. 2023-167368

[0016] Non-patent literature

[0017] [Non-Patent Literature 1] SPIE Vol.5039p1 (2003)

[0018] [Non-Patent Literature 2] SPIE Vol.6520p65203L-1(2007) Summary of the Invention

[0019] [The problem that the invention aims to solve]

[0020] The present invention was made in view of the foregoing circumstances, and aims to provide a resist composition with excellent sensitivity and resolution in optical lithography using high-energy rays, especially electron beam (EB) lithography and EUV lithography, and to provide a laminate and a method for forming a pattern using the resist composition.

[0021] [Methods for solving the problem]

[0022] To address the aforementioned issues, the present invention provides a resist composition characterized by containing a high-valent iodine compound represented by formula (1), a carboxyl-containing compound, and a solvent.

[0023] [Chemistry 1]

[0024]

[0025] In the formula, m is an integer from 0 to 2, n is an integer from 0 to 4 when m is 0, an integer from 0 to 6 when m is 1, and an integer from 0 to 8 when m is 2. R 1 R 2 R 3 Each group consists of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. R 1 R 2 R 3 They can also bond together to form a loop. R 4 It is a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. When n is 2 or more, each R 4 They can be the same or different. Also, multiple R's... 4 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. R 5 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms. *1 and *2 represent atomic bonds of carbon atoms in the aromatic ring in the formula. However, *1 and *2 are bonded to adjacent carbon atoms on the aromatic ring.

[0026] If the resist composition of the present invention is used, it exhibits excellent sensitivity and resolution in optical lithography using high-energy rays, especially electron beam (EB) lithography and EUV lithography.

[0027] In this invention, the aforementioned carboxyl-containing compound may be any one or both of a polymer containing a repeating unit represented by formula (2) and a compound represented by formula (3).

[0028] [Chemistry 2]

[0029]

[0030] In the formula, R A It can be a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group. X A It is a single bond, phenylene, naphthylene, or *-C(=O)-OX A1 -. X A1 It is a saturated hydrocarbon group, phenylene group, or naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbon group may also contain a hydroxyl group, ether bond, ester bond, or lactone ring. * indicates an atomic bond with a carbon atom in the main chain. p is 1, 2, 3, or 4. R 31 R is a p-valent hydrocarbon group with 1 to 40 carbon atoms or a p-valent heterocyclic group with 2 to 40 carbon atoms; when p is 2, R 31 It can also be an ether bond, carbonyl group, azo group, thioether bond, carbonate bond, carbamate bond, sulfinyl group, or sulfonyl group. Furthermore, some or all of the hydrogen atoms in the aforementioned p-valent hydrocarbon group or p-valent heterocyclic group can be substituted by a group containing a heteroatom, and a portion of the -CH2- group in the aforementioned p-valent hydrocarbon group can also be substituted by a group containing a heteroatom. R 32 It is a single bond or a hydrocarbon group with 1 to 20 carbon atoms, and some or all of the hydrogen atoms of the hydrocarbon group can be replaced by a group containing a heteroatom, and part of the -CH2- of the hydrocarbon group can also be replaced by a group containing a heteroatom. When p is 2, 3 or 4, each R 32 They can be the same or different.

[0031] The carboxyl-containing compounds contained in the resist composition of the present invention are preferably polymers or monomeric compounds of such nature.

[0032] The resist composition of the present invention preferably contains at least one of the high-valent iodine compounds represented by formula (4) or (5).

[0033] [Chemistry 3]

[0034]

[0035] In the formula, m1 and m2 are integers from 0 to 2. n1 is an integer from 0 to 4 when m1 is 0, an integer from 0 to 6 when m1 is 1, and an integer from 0 to 8 when m1 is 2. When m2 is 0, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 5, satisfying 1 ≤ (n2 + n3) ≤ 6. When m2 is 1, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 7, satisfying 1 ≤ (n2 + n3) ≤ 8. When m2 is 2, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 9, satisfying 1 ≤ (n2 + n3) ≤ 10. R 41 A hydrocarbon group consisting of 1 to 10 carbon atoms, which may also contain heteroatoms. R 42 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. When n1 is 2 to 6, each R 42 They can be the same or different. Also, multiple R's... 42 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. R 43 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms. *3 and *4 represent atomic bonds of the carbon atoms in the aromatic ring in the formula. However, *3 and *4 must be bonded to adjacent carbon atoms on the aromatic ring. R 51 and R 52 Each group consists independently of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. Also, R 51 and R 52 They can also bond to each other and form rings together with the carbon atoms they are bonded to and the atoms between those carbon atoms. When n2 is 2 to 3, each R 51 and R 52 They can be the same or different. R 53 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. When n3 is 2 to 9, each R 53 They can be the same or different. Also, multiple R's... 53 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

[0036] The present invention allows for the control of the light reactivity of the composition and the adjustment of its sensitivity by using at least one of high-valent iodine compounds containing such iodine (III).

[0037] Furthermore, the present invention provides a laminated body characterized by comprising:

[0038] substrate, and

[0039] The resist film on the substrate is a film-forming body of the aforementioned resist composition.

[0040] The laminate containing the resist film derived from the resist composition of the present invention has a wide range of applications and is highly useful in resist manufacturing technology because the resist film of the resist composition is highly sensitive and exhibits excellent resolution. It is effective for precision micro-machining and can be used for forming any type of pattern, whether positive or negative.

[0041] At this point, a lower resist film may be provided between the aforementioned substrate and the aforementioned resist film. Furthermore, it is preferable that the aforementioned resist film is a laminate containing the ligand exchange reaction product of the aforementioned high-valent iodine compound and a carboxyl-containing compound.

[0042] The laminate of the present invention can be configured in such a manner as required.

[0043] Furthermore, the present invention provides a pattern forming method, characterized by comprising the following steps:

[0044] A resist film is formed on a substrate or on the resist underlayer film of a substrate having a resist underlayer film laminated thereon using the above-described resist composition.

[0045] The aforementioned resist film was exposed to high-energy rays, and

[0046] The previously exposed resist film was developed using a developer.

[0047] If it is the pattern forming method of the present invention, it is useful for forming finer patterns because of the use of a specific resist composition; the specific resist composition has excellent sensitivity and resolution in optical lithography using high-energy rays, especially electron beam (EB) lithography and EUV lithography.

[0048] At this time, the aforementioned high-energy rays should preferably be i-rays, KrF excimer lasers, ArF excimer lasers, electron beams, or extreme ultraviolet rays.

[0049] The pattern forming method of the present invention can form finer patterns by using such high-energy rays.

[0050] In the pattern forming method of the present invention, the developer may be used to dissolve the exposed portion without dissolving the unexposed portion, or it may be used to dissolve the unexposed portion without dissolving the exposed portion.

[0051] The pattern forming method of the present invention can form positive or negative patterns by appropriately selecting the developing solution, and is therefore widely applicable to the formation of various fine patterns.

[0052] [The effects of the invention]

[0053] The resist composition of the present invention is particularly useful in EB lithography and EUV lithography, as it combines high sensitivity and high resolution, making it extremely useful in forming fine patterns. Detailed Implementation

[0054] The inventors, through repeated and in-depth exploration in order to achieve the above-mentioned objectives, have obtained the following insights and thus completed the present invention: a resist composition with a predetermined high-valent iodine compound and a carboxyl-containing compound (polymer or monomer compound) as the main components can provide a resist film with extremely high sensitivity and excellent resolution, which is extremely effective for precision micro-machining.

[0055] That is, the present invention is a resist composition characterized by containing a high-valent iodine compound represented by the following formula (1), a carboxyl-containing compound, and a solvent.

[0056] [Chemistry 4]

[0057]

[0058] In the formula, m is an integer from 0 to 2, n is an integer from 0 to 4 when m is 0, an integer from 0 to 6 when m is 1, and an integer from 0 to 8 when m is 2. R 1 R 2 R 3 Each group consists of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. R 1 R 2 R 3 They can also bond together to form a loop. R 4 It is a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. When n is 2 or more, each R 4 They can be the same or different. Also, multiple R's... 4 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. R 5 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms. *1 and *2 represent atomic bonds of carbon atoms in the aromatic ring in the formula. However, *1 and *2 are bonded to adjacent carbon atoms on the aromatic ring.

[0059] The present invention will now be described in detail, but it is not limited thereto. Furthermore, in this specification, references to the endpoints of a numerical range are defined as including all values ​​contained within that range (e.g., "0 to 3" includes 0, 1, 2, and 3).

[0060] [Resist Composition]

[0061] The resist composition of the present invention contains a predetermined high-valent iodine compound, a carboxyl-containing compound, and a solvent as the main components.

[0062] [High-valent iodine compounds]

[0063] High-valence iodine compounds refer to the general term for iodine compounds that have valence electrons in a form that exceeds the octet rule. Examples include tricoordinate iodine compounds (iodine(III) compounds) with an oxidation number of +3 and pentacoordinate iodine compounds (iodine(V) compounds) with an oxidation number of +5.

[0064] The aforementioned high-valent iodine compound, which is the main component of the resist composition of the present invention, is a pentacoordinate high-valent iodine compound represented by the following formula (1).

[0065] [Chemistry 5]

[0066]

[0067] In the formula, m is an integer from 0 to 2, n is an integer from 0 to 4 when m is 0, an integer from 0 to 6 when m is 1, and an integer from 0 to 8 when m is 2. R 1 R 2 R 3 Each group consists of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. R 1 R 2 R 3 They can also bond together to form a loop. R 4 It is a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. When n is 2 or more, each R 4 They can be the same or different. Also, multiple R's... 4 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. R 5 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms. *1 and *2 represent atomic bonds of carbon atoms in the aromatic ring in the formula. However, *1 and *2 are bonded to adjacent carbon atoms on the aromatic ring.

[0068] In equation (1), m is an integer from 0 to 2, and n is an integer from 0 to 4 when m is 0, an integer from 0 to 6 when m is 1, and an integer from 0 to 8 when m is 2. n is preferably 0 to 8, 0 to 6 is better, 0 to 4 is even better, 0 to 2 is still better, and 0 or 1 is optimal. Furthermore, when m is 0, the aromatic ring is a benzene ring.

[0069] In equation (1), R 1 R 2 R 3Alkyl groups having 1 to 10 carbon atoms, each independently consisting of a halogen atom or possibly containing heteroatoms. Specific examples of the aforementioned halogen atoms include: fluorine, chlorine, bromine, iodine, etc. The aforementioned alkyl groups having 1 to 10 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc., alkyl groups having 1 to 10 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6 [Cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms, such as decyl and adamantyl; alkenyl groups with 2 to 10 carbon atoms, such as vinyl and allyl; aryl groups with 6 to 10 carbon atoms, such as phenyl and naphthyl; and groups obtained by combining them. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups may be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups may also be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, groups may contain hydroxyl, cyano, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone, sulpholactone, carboxylic anhydride (-C(=O)-OC(=O)-), etc.] 1 It is preferable to use a hydrocarbon group with 1 to 4 carbon atoms or a fluorinated hydrocarbon group with 1 to 4 carbon atoms, with a hydrocarbon group with 1 to 4 carbon atoms being more preferred.

[0070] In equation (1), R 4 A hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. Specific examples of the aforementioned halogen atoms include: fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. The aforementioned hydrocarbon group with 1 to 40 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc., alkyl groups with 1 to 40 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6[Cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; aryl groups with 6 to 40 carbon atoms, such as phenyl, naphthyl, and anthracene. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups can also be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. As a result, hydroxyl, cyano, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone ring, sulfonyl ring, carboxylic anhydride (-C(=O)-OC(=O)-), etc. When n is 2 or more, each R...] 4 They can be the same or different. Also, multiple R's... 4 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. Also, R 4 It can replace any position of the aromatic ring in formula (1).

[0071] In equation (1), R 5 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may contain heteroatoms. The aforementioned hydrocarbon groups with 1 to 10 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkylene groups with 1 to 10 carbon atoms, such as methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-2,3-diyl, butane-1,4-diyl, 2-methylpropane-1,2-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, and decane-1,10-diyl; cyclopentanediyl, cyclohexanediyl, norcamphenediyl, adamantanediyl, and tricyclic [5.2.1.0] 2,6 [Cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms, such as decanediyl; vinylidene, propenide, etc., with 2 to 10 carbon atoms; arylene groups with 6 to 10 carbon atoms, such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, naphthylene; and groups obtained by combining these. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups may be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups may also be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, groups may contain hydroxyl, cyano, halogenated alkyl, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), etc.] 5 It is preferable to use a carbonyl group, a hydrocarbon group with 1 to 4 carbon atoms, or a fluorinated hydrocarbon group with 1 to 4 carbon atoms.

[0072] In equation (1), *1 and *2 represent the atomic bonds of the carbon atoms in the aromatic ring. However, *1 and *2 are bonded to adjacent carbon atoms in the aromatic ring. Such combinations of *1, *2, and m can be considered in the following seven states.

[0073] [Chemistry 6]

[0074]

[0075] In the formula, n and R 2 and R 3 Same as above. Dashed lines represent acyl groups (R). 1 -C(=O)-O-、R 2 -C(=O)-O-, and R 3 -C(=O)-O-) atomic bonds.

[0076] Specific examples of high-valent iodine compounds represented by formula (1) are shown below, but are not limited thereto. Additionally, in the following formula, Me represents a methyl group.

[0077] [Chemistry 7]

[0078]

[0079] [Chemistry 8]

[0080]

[0081] [Chemistry 9]

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[0083] [Chemistry 10]

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[0087] [Chemistry 12]

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[0111] [Chemistry 24]

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[0125] [Chemistry 31]

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[0127] [Chemistry 32]

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[0129] [Chemistry 33]

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[0131] [Chemistry 34]

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[0157] [Chemistry 47]

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[0159] [Chemistry 48]

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[0161] [Chemistry 49]

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[0163] [Transformation 50]

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[0165] [Chemistry 51]

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[0167] [Chemistry 52]

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[0169] [Chemistry 53]

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[0171] [Chemistry 54]

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[0177] [Chemistry 57]

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[0179] [Chem.58]

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[0181] [Chemistry 59]

[0182]

[0183] [Compounds containing carboxyl groups]

[0184] The aforementioned carboxyl-containing compounds are preferably polymers containing repeating units represented by formula (2) below, and compounds represented by formula (3) below, or both.

[0185] [Transformation 60]

[0186]

[0187] In equation (2), R A It can be a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group. X A It is a single bond, phenylene, naphthylene, or *-C(=O)-OX A1 -. X A1 It is a saturated hydrocarbon group, phenylene group, or naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbon group may also contain a hydroxyl group, ether bond, ester bond, or lactone ring. * indicates an atomic bond with a carbon atom in the main chain.

[0188] In equation (3), p is 1, 2, 3 or 4.

[0189] In equation (3), R 31 R is a p-valent hydrocarbon group with 1 to 40 carbon atoms or a p-valent heterocyclic group with 2 to 40 carbon atoms; when p is 2, R 31 It can also be an ether bond, carbonyl group, azo group, thioether bond, carbonate bond, carbamate bond, sulfinyl group, or sulfonyl group. Furthermore, some or all of the hydrogen atoms of the aforementioned p-valent hydrocarbon group or p-valent heterocyclic group can be replaced by a group containing heteroatoms, and part of the -CH2- of the aforementioned p-valent hydrocarbon group can also be replaced by a group containing heteroatoms.

[0190] In equation (3), R 32 It is a single bond or a hydrocarbon group with 1 to 20 carbon atoms, and some or all of the hydrogen atoms of the hydrocarbon group can be replaced by a group containing a heteroatom, and part of the -CH2- of the hydrocarbon group can also be replaced by a group containing a heteroatom. When p is 2, 3 or 4, each R 32 They can be the same or different.

[0191] R 31The p-valent hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. The aforementioned p-valent hydrocarbon group is obtained by removing p hydrogen atoms from a hydrocarbon. Examples of such hydrocarbons include: alkanes with 1-40 carbon atoms, alkenes with 2-40 carbon atoms, alkynes with 2-40 carbon atoms, cyclic saturated hydrocarbons with 3-40 carbon atoms, cyclic unsaturated hydrocarbons with 3-40 carbon atoms, and aromatic hydrocarbons with 6-40 carbon atoms.

[0192] The aforementioned alkanes with 1 to 40 carbon atoms include: methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, and their structural isomers.

[0193] The aforementioned alkenes with 2 to 40 carbon atoms include: ethylene, propylene, butene, pentene, hexene, hepten, octene, nonene, decene, and their structural isomers.

[0194] The aforementioned alkynes with 2 to 40 carbon atoms can be listed as follows: acetylene, propyne, butyne, pentyne, hexyne, heptyne, octyne, nonyne, decyne, and their structural isomers.

[0195] Examples of cyclic saturated hydrocarbons with 3 to 40 carbon atoms include: cyclopropane, cyclobutane, cyclohexane, cycloheptane, cyclooctane, adamantane, norcamphene, etc.

[0196] Examples of cyclic unsaturated hydrocarbons with 3 to 40 carbon atoms include: cyclopropylene, cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene, and norcamphene.

[0197] Aromatic hydrocarbons with 6 to 40 carbon atoms mentioned above include: benzene, naphthalene, biphenyl, etc.

[0198] R 31 The p-valent heterocyclic group represents a group obtained by removing p hydrogen atoms from a heterocyclic compound. Examples of such heterocyclic compounds include furan, pyridine, pyrazole, and tetrahydrothiazole.

[0199] The hydrogen atoms of the aforementioned p-valent hydrocarbon groups or p-valent heterocyclic groups can be partially or completely replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms, resulting in the presence of hydroxyl, cyano, fluorine, chlorine, bromine, and iodine atoms. Furthermore, in the aforementioned p-valent hydrocarbon groups, a portion of the -CH2- group can be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms, resulting in the presence of carbonyl groups, ether bonds, thioether bonds, ester bonds, sulfonate bonds, carbonate bonds, carbamate bonds, lactone rings, sulopentalide rings, and carboxylic anhydrides (-C(=O)-OC(=O)-), etc.

[0200] R 32The alkylene groups representing carbon atoms from 1 to 20 can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1, Alkyl groups with 1 to 20 carbon atoms, such as 11-diyl and dodecane-1,12-diyl; cyclic saturated alkylene groups with 3 to 20 carbon atoms, such as cyclopentanediyl, cyclohexanediyl, norcamphenediyl, and adamantanediyl; unsaturated aliphatic alkylene groups with 2 to 20 carbon atoms, such as vinylene and propylene-1,3-diyl; aryl groups with 6 to 20 carbon atoms, such as phenylene and naphthylene; and groups obtained by combining them. Furthermore, some or all of the hydrogen atoms in the aforementioned alkylene group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and a portion of the -CH2- constituting the aforementioned alkylene group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, cyano groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, carbonyl groups, ether bonds, thioether bonds, ester bonds, sulfonate bonds, carbonate bonds, carbamate bonds, lactone rings, sulcinolone rings, carboxylic anhydrides, etc.

[0201] Among the carboxylic acid compounds (monomers) represented by formula (3), those with p = 2, 3, or 4 are preferable. In this case, when mixed with high-valent iodine compounds, it is easy to form a high-molecular-weight, strong resist film, which is ideal considering etching resistance and developer resistance.

[0202] Specific examples of the repeating unit containing a carboxyl group represented by equation (2) are shown below, but are not limited thereto. Additionally, in the following equation, R... A Same as above.

[0203] [Chemistry 61]

[0204]

[0205] [Chemistry 62]

[0206]

[0207] Carboxylic acid compounds represented by formula (3) can be listed below, but are not limited to. Carboxylic acid compounds can be commercially available or synthesized.

[0208] [Chemistry 63]

[0209]

[0210] [Chemistry 64]

[0211]

[0212] [Chemistry 65]

[0213]

[0214] [Chemistry 66]

[0215]

[0216] [Chemistry 67]

[0217]

[0218] [Chemistry 68]

[0219]

[0220] Polymers containing carboxyl groups that contain repeating units represented by formula (2) may also contain repeating units other than those represented by formula (2) (hereinafter also referred to as other repeating units). There are no particular limitations on the aforementioned other repeating units, but they should preferably be those that can improve the solubility of polymers that are poorly soluble in solvents when only repeating units with carboxyl groups are present. The aforementioned other repeating units should preferably be repeating units with a ring structure that can be expected to have high etch resistance due to a rigid backbone, or repeating units containing a styrene backbone.

[0221] Specific examples of the aforementioned repeating units may be listed below, but are not limited to these. Additionally, in the following formula, R... A As mentioned above, X B They are either -CH2- or -O-, respectively.

[0222] [Chemistry 69]

[0223]

[0224] [Chemistry 70]

[0225]

[0226] [Chemistry 71]

[0227]

[0228] [Chemistry 72]

[0229]

[0230] [Chemistry 73]

[0231]

[0232] [Chemistry 74]

[0233]

[0234] [Chemistry 75]

[0235]

[0236] [Chemistry 76]

[0237]

[0238] [Chemistry 77]

[0239]

[0240] [Chemistry 78]

[0241]

[0242] [Chemistry 79]

[0243]

[0244] [Chemistry 80]

[0245]

[0246] [Chemistry 81]

[0247]

[0248] [Chemistry 82]

[0249]

[0250] [Chemistry 83]

[0251]

[0252] [Chemistry 84]

[0253]

[0254] [Chemistry 85]

[0255]

[0256] [Chemistry 86]

[0257]

[0258] [Chemistry 87]

[0259]

[0260] [Chemistry 88]

[0261]

[0262] [Chemistry 89]

[0263]

[0264] [Chemistry 90]

[0265]

[0266] [Chemistry 91]

[0267]

[0268] [Chemistry 92]

[0269]

[0270] [Chemistry 93]

[0271]

[0272] [Chemistry 94]

[0273]

[0274] [Chem. 95]

[0275]

[0276] [Chemistry 96]

[0277]

[0278] [Chemistry 97]

[0279]

[0280] [Chem. 98]

[0281]

[0282] In the aforementioned resist composition, the molar ratio of the aforementioned high-valent iodine compound to the aforementioned carboxyl-containing compound (polymer containing repeating units represented by formula (2) and / or compound represented by formula (3)) is preferably high-valent iodine compound: carboxyl-containing compound = 1:99 to 99:1, more preferably 10:90 to 90:10, and even more preferably 20:80 to 80:20. The aforementioned high-valent iodine compound may be used alone or in combination with two or more. The aforementioned carboxyl-containing polymer may be used alone or in combination with two or more polymers with different composition ratios, weight-average molecular weight (Mw), and / or molecular weight distribution (Mw / Mn). The aforementioned monomolecular compounds may be used alone or in combination of two or more. The aforementioned carboxyl-containing polymers and the aforementioned monomolecular compounds may be used individually or in combination.

[0283] In the aforementioned carboxyl-containing polymers, the molar ratio of carboxyl-containing repeating units to other repeating units should preferably be 10:90 to 90:10, more preferably 15:85 to 85:15, and even more preferably 20:80 to 80:20.

[0284] The weight-average molecular weight (Mw) of the aforementioned carboxyl-containing polymers is preferably between 1,000 and 500,000, and more preferably between 3,000 and 100,000. Furthermore, in this invention, Mw and number-average molecular weight Mn are converted values ​​from standard polystyrene determined by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.

[0285] Furthermore, when the aforementioned carboxyl-containing polymers have a wide molecular weight distribution (Mw / Mn), the presence of both low and high molecular weight polymers may lead to concerns about foreign matter being observed on the pattern after exposure and deterioration of the pattern shape. Therefore, as the pattern becomes more regular and refined, the influence of Mw and Mw / Mn tends to increase. Thus, in order to obtain a resist composition that can be ideally used for fine pattern sizes, the aforementioned carboxyl-containing polymers should preferably have a narrow dispersion of Mw / Mn of 1.0 to 2.0.

[0286] Examples of methods for synthesizing the aforementioned carboxyl-containing polymers include: polymerizing a monomer that provides the aforementioned repeating unit in an organic solvent by adding a free radical polymerization initiator and heating it.

[0287] Specific examples of organic solvents used in the polymerization reaction include: toluene, benzene, THF, diethyl ether, dioxane, cyclohexane, cyclopentane, cyclopentanone, cyclohexanone, methyl ethyl ketone (MEK), propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), γ-butyrolactone (GBL), etc. Specific examples of polymerization initiators include: 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylpentanonitrile), dimethyl-2,2-azobis(2-methylpropionate), 1,1'-azobis(1-acetoxy-1-phenylethane), benzoyl peroxide, lauroyl peroxide, etc. The amount of the aforementioned polymerization initiator added, relative to the total amount of monomers used to polymerize, should preferably be 0.01–25 mol%. The reaction temperature should preferably be 50–150 °C, preferably 60–100 °C. The reaction time should be 2 to 24 hours, but from the perspective of production efficiency, 2 to 12 hours is better.

[0288] The aforementioned polymerization initiator can be added to the aforementioned monomer solution and supplied to the reactor, or a separate initiator solution different from the aforementioned monomer solution can be prepared and supplied to the reactor independently. Since there is a possibility that polymerization may proceed and generate ultra-high molecular weight polymers due to the generation of free radicals from the initiator during the standby time, from a quality management perspective, the monomer solution and initiator solution should preferably be prepared independently and added dropwise. Furthermore, to adjust the molecular weight, known chain transfer agents such as dodecyl mercaptan and 2-mercaptoethanol can also be used in combination. In this case, the amount of the aforementioned chain transfer agent added, relative to the total amount of monomers used to polymerize it, should preferably be 0.01 to 20 mol%.

[0289] In addition, the amount of each monomer in the aforementioned monomer solution can be appropriately set to achieve the ideal content ratio of the aforementioned repeating units.

[0290] [Other high-valent iodine compounds]

[0291] The resist composition of the present invention may further contain at least one of the high-valent iodine compounds (hereinafter also referred to as other high-valent iodine compounds) represented by formula (4) or (5). By adding other high-valent iodine compounds (iodine (III) compounds), the reactivity to light can be controlled and the sensitivity adjusted.

[0292] [Chemistry 99]

[0293]

[0294] In the formula, m1 and m2 are integers from 0 to 2. n1 is an integer from 0 to 4 when m1 is 0, an integer from 0 to 6 when m1 is 1, and an integer from 0 to 8 when m1 is 2. When m2 is 0, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 5, satisfying 1 ≤ (n2 + n3) ≤ 6. When m2 is 1, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 7, satisfying 1 ≤ (n2 + n3) ≤ 8. When m2 is 2, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 9, satisfying 1 ≤ (n2 + n3) ≤ 10. R 41 A hydrocarbon group consisting of 1 to 10 carbon atoms, which may also contain heteroatoms. R 42 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. When n1 is 2 to 6, each R 42 They can be the same or different. Also, multiple R's... 42 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. R 43 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms. *3 and *4 represent atomic bonds of the carbon atoms in the aromatic ring in the formula. However, *3 and *4 must be bonded to adjacent carbon atoms on the aromatic ring. R 51 and R 52 Each group consists independently of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. Also, R 51 and R 52 They can also bond to each other and form rings together with the carbon atoms they are bonded to and the atoms between those carbon atoms. When n2 is 2 to 3, each R 51 and R 52 They can be the same or different. R 53 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. When n3 is 2 to 9, each R 53 They can be the same or different. Also, multiple R's... 53 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

[0295] In the above general formula (4), m1 is an integer from 0 to 2. n1 is an integer from 0 to 4 when m1 is 0, an integer from 0 to 6 when m1 is 1, and an integer from 0 to 8 when m1 is 2. n1 should preferably be 0, 1, 2, 3 or 4, preferably 0, 1, 2 or 3, even better if it is 0, 1 or 2, and best if it is 0 or 1.

[0296] In the above general formula (4), R 41A hydrocarbon group having 1 to 10 carbon atoms, which may contain halogen atoms or heteroatoms. Specific examples of the aforementioned halogen atoms include: fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. The aforementioned hydrocarbon groups having 1 to 10 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc., alkyl groups having 1 to 10 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6 [Cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms, such as decyl and adamantyl; alkenyl groups with 2 to 10 carbon atoms, such as vinyl and allyl; aryl groups with 6 to 10 carbon atoms, such as phenyl and naphthyl; and groups obtained by combining them. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups may be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups may also be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, groups may contain hydroxyl, cyano, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone, sulpholactone, carboxylic anhydride (-C(=O)-OC(=O)-), etc.] 41 It is preferable to use a hydrocarbon group with 1 to 4 carbon atoms or a fluorinated hydrocarbon group with 1 to 4 carbon atoms, with a hydrocarbon group with 1 to 4 carbon atoms being more preferred.

[0297] In the above general formula (4), R 42 A hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. Specific examples of the aforementioned halogen atoms include: fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. The aforementioned hydrocarbon group with 1 to 40 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc., alkyl groups with 1 to 40 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6[Cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; aryl groups with 6 to 40 carbon atoms, such as phenyl, naphthyl, and anthracene. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups can also be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. As a result, hydroxyl, cyano, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone ring, sulfonyl ring, carboxylic anhydride (-C(=O)-OC(=O)-), etc. When n1 is 2 to 8, each R...] 42 They can be the same or different. Also, multiple R's... 42 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

[0298] In the above general formula (4), R 43 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may contain heteroatoms. The aforementioned hydrocarbon groups with 1 to 10 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkylene groups with 1 to 10 carbon atoms, such as methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-2,3-diyl, butane-1,4-diyl, 2-methylpropane-1,2-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, and decane-1,10-diyl; cyclopentanediyl, cyclohexanediyl, norcamphenediyl, adamantanediyl, and tricyclic [5.2.1.0] 2,6 [Cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms, such as decanediyl; vinylidene, propenide, etc., with 2 to 10 carbon atoms; arylene groups with 6 to 10 carbon atoms, such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, naphthylene; and groups obtained by combining these. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups may be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups may also be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, groups may contain hydroxyl, cyano, halogenated alkyl, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), etc.] 43 It is preferable to use a carbonyl group, a hydrocarbon group with 1 to 4 carbon atoms, or a fluorinated hydrocarbon group with 1 to 4 carbon atoms.

[0299] In the above general formula (4), *3 and *4 represent the atomic bonds of the carbon atoms in the aromatic ring. However, *3 and *4 are bonded to adjacent carbon atoms on the aromatic ring. Such combinations of *3, *4 and m1 can be considered in the following 7 states.

[0300] [Chemistry 100]

[0301]

[0302] In the formula, n1 and R 42 and R 43 Same as above. The dashed line represents R. 41 -C(=O)-O- atomic bonds.

[0303] Specific examples of high-valent iodine compounds represented by the above general formula (4) are shown below, but are not limited thereto. Additionally, in the following formula, Me is a methyl group.

[0304] [Chemistry 101]

[0305]

[0306] [Chemistry 102]

[0307]

[0308] [Chemistry 103]

[0309]

[0310] [Chemistry 104]

[0311]

[0312] [Chemistry 105]

[0313]

[0314] [Chemistry 106]

[0315]

[0316] [Chemistry 107]

[0317]

[0318] [Chemistry 108]

[0319]

[0320] [Chemistry 109]

[0321]

[0322] [Chemical 110]

[0323]

[0324] [Chemistry 111]

[0325]

[0326] [Chemistry 112]

[0327]

[0328] [Chemistry 113]

[0329]

[0330] [Chemistry 114]

[0331]

[0332] [Chemistry 115]

[0333]

[0334] [Chemistry 116]

[0335]

[0336] [Chemistry 117]

[0337]

[0338] [Chemistry 118]

[0339]

[0340] [Chemistry 119]

[0341]

[0342] [Chemistry 120]

[0343]

[0344] [Chemistry 121]

[0345]

[0346] [Chemistry 122]

[0347]

[0348] [Chemistry 123]

[0349]

[0350] [Chemistry 124]

[0351]

[0352] [Chemistry 125]

[0353]

[0354] [Chemistry 126]

[0355]

[0356] [Chemistry 127]

[0357]

[0358] [Chemistry 128]

[0359]

[0360] [Chemistry 129]

[0361]

[0362] [Chemistry 130]

[0363]

[0364] [Chemistry 131]

[0365]

[0366] [Chemistry 132]

[0367]

[0368] [Chemistry 133]

[0369]

[0370] [Chemistry 134]

[0371]

[0372] [Chemistry 135]

[0373]

[0374] [Chemistry 136]

[0375]

[0376] [Chemistry 137]

[0377]

[0378] [Chemistry 138]

[0379]

[0380] [Chemistry 139]

[0381]

[0382] [Chemistry 140]

[0383]

[0384] [Chemistry 141]

[0385]

[0386] [Chemistry 142]

[0387]

[0388] [Chemistry 143]

[0389]

[0390] [Chemistry 144]

[0391]

[0392] [Chemistry 145]

[0393]

[0394] [Chemistry 146]

[0395]

[0396] [Chemistry 147]

[0397]

[0398] [Chemistry 148]

[0399]

[0400] [Chemistry 149]

[0401]

[0402] [Chemistry 150]

[0403]

[0404] [Chemistry 151]

[0405]

[0406] [Chemistry 152]

[0407]

[0408] [Chemistry 153]

[0409]

[0410] [Chemistry 154]

[0411]

[0412] [Chemistry 155]

[0413]

[0414] [Chemistry 156]

[0415] In the above general formula (5), m2 is an integer from 0 to 2.

[0416] When m2 is 0, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 5, and 1 ≤ (n2 + n3) ≤ 6. When m2 is 1, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 7, and 1 ≤ (n2 + n3) ≤ 8. When m2 is 2, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 9, and 1 ≤ (n2 + n3) ≤ 10.

[0417] In the above general formula (5), R 51 and R 52 Each group consists independently of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. Also, R 51 and R 52 They can also bond to each other and form rings together with the carbon atoms they are bonded to and the atoms between those carbon atoms. Examples of halogen atoms include: fluorine, chlorine, bromine, iodine, etc. The aforementioned hydrocarbon groups with 1 to 10 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc., alkyl groups with 1 to 10 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6[Cyclic saturated hydrocarbon groups with 3 to 10 carbon atoms, such as decyl and adamantyl; alkenyl groups such as vinyl and allyl; aryl groups with 6 to 10 carbon atoms, such as phenyl and naphthyl; and groups obtained by combining them. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups may be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups may also be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, groups may contain hydroxyl, cyano, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), etc.] 51 and R 52 It should preferably be a hydrocarbon group with 1 to 4 carbon atoms.

[0418] In the above general formula (5), R 53 A hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine. The hydrocarbon group with 1 to 40 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc., alkyl groups with 1 to 40 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6 [Cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; aryl groups with 6 to 40 carbon atoms, such as phenyl, naphthyl, and anthracene. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon groups can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, and halogen atoms, and a portion of the -CH2- group in the aforementioned hydrocarbon groups can also be replaced by groups containing heteroatoms such as oxygen, sulfur, and nitrogen atoms. As a result, hydroxyl, cyano, halogen, carbonyl, ether, thioether, ester, sulfonate, carbonate, carbamate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), etc. When n3 is 2 to 9, each R...] 53 They can be the same or different. Also, multiple R's... 53 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

[0419] Specific examples of high-valent iodine compounds represented by the above general formula (5) are listed below, but are not limited thereto.

[0420] [Chemistry 157]

[0421]

[0422] [Chemistry 158]

[0423]

[0424] [Chemistry 159]

[0425]

[0426] [Chemistry 160]

[0427]

[0428] When the resist composition of the present invention contains other high-valent iodine compounds, the other high-valent iodine compounds may be the high-valent iodine compounds represented by the above general formula (4), or the high-valent iodine compounds represented by the above general formula (5), or a combination of the high-valent iodine compounds represented by the above general formula (4) and the high-valent iodine compounds represented by the above general formula (5). Furthermore, the high-valent iodine compounds represented by the above general formula (4) and the high-valent iodine compounds represented by the above general formula (5) may each be used individually, or two or more different compounds may be used in combination.

[0429] When the resist composition of the present invention contains other high-valent iodine compounds, the molar ratio of the aforementioned high-valent iodine compounds to the aforementioned carboxyl-containing compounds (when the aforementioned carboxyl-containing compounds are carboxyl-containing polymers, it is the molar ratio of the high-valent iodine compounds in the aforementioned polymers to the repeating units containing carboxylic acids) is preferably 1:99 to 99:1, more preferably 10:90 to 90:10, and even more preferably 20:80 to 80:20. Furthermore, the molar ratio of the aforementioned other high-valent iodine compounds to the high-valent iodine compound represented by formula (1) is preferably such that the ratio of other high-valent iodine compounds to the high-valent iodine compound represented by formula (1) is 1:99 to 99:1, and more preferably 1:99 to 50:50.

[0430] [solvent]

[0431] The resist composition of the present invention contains a solvent. There are no particular limitations on the solvent being a soluble high-valent iodine compound represented by formula (1), a carboxyl-containing polymer, other high-valent iodine compounds, and other components described below, and capable of forming a film. Such a solvent is preferably an organic solvent, and specific examples include: ketones such as cyclohexanone, methyl-2-n-pentyl ketone, and methyl isopentyl ketone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, diacetone alcohol, 4-methyl-2-pentanol, and methyl 2-hydroxyisobutyrate; and propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, and ethylene glycol monoethyl ether. Ethers such as monoethyl ether of alcohol, dimethyl propylene glycol, and dimethyl ethylene glycol; esters such as propylene glycol monomethyl ether acetate, monoethyl propylene glycol acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and monotert-butyl propylene glycol acetate; carboxylic acids such as formic acid, acetic acid, and propionic acid; lactones such as γ-butyrolactone; and their mixed solvents, etc.

[0432] In the resist composition of the present invention, the content of the aforementioned solvent is preferably such that the concentration of the solid component in the resist composition is 0.1% to 20% by mass, more preferably 0.1% to 15% by mass, and even more preferably 0.1% to 10% by mass. Furthermore, in the present invention, the solid component refers to the total components other than the solvent in the entire composition of the resist. The aforementioned solvent may be used alone or in combination of two or more.

[0433] [Other ingredients]

[0434] The resist composition of the present invention may further contain a surfactant. The aforementioned surfactant is preferably a fluorinated and / or polysiloxane surfactant. Specific examples of such surfactants include the surfactant described in paragraph

[0276] of U.S. Patent Application Publication 2008 / 0248425. Alternatively, surfactants other than the fluorinated and / or polysiloxane surfactants described in paragraph

[0280] of U.S. Patent Application Publication 2008 / 0248425 may also be used.

[0435] When the resist composition of the present invention contains the aforementioned surfactant, its content in the total solid components is preferably 0.0001 to 2% by mass. The aforementioned surfactant may be used alone or in combination of two or more.

[0436] The resist composition of the present invention may further contain at least one selected from free radical scavengers and crosslinking agents. This allows for control of the photoresponse during optical lithography and adjustment of sensitivity.

[0437] Specific examples of the aforementioned free radical scavengers include hindered phenols, quinones, hindered amines, and thiols. Specifically, examples of hindered phenols include butylated hydroxytoluene (BHT) and 2,2'-methylenebis(4-methyl-6-tert-butylphenol). Examples of quinones include 4-methoxyphenol and hydroquinone. Examples of hindered amines include 2,2,6,6-tetramethylpiperidine and 2,2,6,6-tetramethylpiperidine-N-oxy radical. Examples of thiols include dodecanethiol and hexadecanethiol.

[0438] When the corrosion resist composition of the present invention contains the aforementioned free radical scavenger, its content in the total solid components is preferably 0.01 to 10% by mass. The aforementioned free radical scavenger may be used alone or in combination of two or more.

[0439] Specific examples of the aforementioned crosslinking agents include compounds with carbon-carbon unsaturated bonds as functional groups, such as vinyl, (meth)acrylate, allyl, alkynyl, and aromatic rings. Specifically, examples of compounds with vinyl groups include: chain alkenes, branched alkenes, and cyclic alkenes, which may also have substituents. Examples of compounds with (meth)acrylate groups include: acrylic acid, methacrylic acid, acrylates, and methacrylates, which may also have substituents. Examples of compounds with allyl groups include: allyl alcohols, allyl ethers, allyl esters, allyl amides, allylamines, and isocyanurates containing allyl groups, which may also have substituents. Examples of compounds with alkynyl groups include: chain alkynes, branched alkynes, cyclic alkynes, alkynyl alcohols, alkynyl ethers, alkynyl esters, alkynyl amides, alkynylamines, and isocyanurates containing alkynyl groups, which may also have substituents. Specific examples of compounds containing aromatic rings include: aromatic hydrocarbons, heteroaromatic hydrocarbons, styrene, stilbene, phenylacetylene, acenaphthene, chalcone, etc., which may also have substituents. The crosslinking agent may contain only one or more of the aforementioned functional groups. Preferably, the crosslinking agent contains 1 or more and 10 or less of the aforementioned functional groups, and more preferably 2 or more and 8 or less.

[0440] When the resist composition of the present invention contains the aforementioned crosslinking agent, its content in the total solid components is preferably 0.01 to 50% by mass. The aforementioned crosslinking agent may be used alone or in combination of two or more.

[0441] The resist composition of the present invention, as described above, contains a high-valent iodine compound and a carboxyl-containing polymer or monomeric compound as its main components, but does not contain the acid-insecure base polymer or photoacid generator found in known chemically amplified resist compositions. However, the resist composition of the present invention, in particular, utilizing EB or EUV exposure, can produce differences in solubility between exposed and unexposed areas, forming positive or negative patterns. The mechanism is not fully elucidated, but is hypothesized as follows.

[0442] The high-valent iodine compound represented by formula (1) is a five-coordinate compound with a carboxylate ligand. It is believed that when such a five-coordinate iodine compound is mixed with a carboxylic acid compound, an equilibrium exchange of carboxylate ligands occurs. If the original carboxylate ligand can be removed by any method, a high-valent iodine compound with a new ligand is generated. For example, mixing Dess-Martin periodinane, which is readily available as a high-valent iodine compound, with a large-molecular-weight carboxylic acid compound and removing the resulting low-boiling acetic acid will complete the ligand exchange. Here, the carboxyl-containing compound becomes a polymer cross-linked by the high-valent iodine compound.

[0443] Polymers crosslinked with high-valent iodine compounds are formed during film formation. This is because even if such crosslinked polymers are synthesized beforehand, they are insoluble in most organic solvents, making solution preparation impossible. It is speculated that this is because the high-valent iodine compounds, which inherently have high polarization and low solvent solubility, use carboxyl-containing compounds as ligands, further worsening their solubility. Therefore, it is advisable to design a step where the low-molecular-weight carboxylic acid components are removed during film formation and the subsequent baking process, thereby completing the ligand exchange reaction and simultaneously forming the resist film.

[0444] In the resist film of the present invention, which is formed on a substrate in this manner, the high-valent iodine compound, as its main component, decomposes under light, thereby changing its polarity and forming a pattern using a development step. Furthermore, by appropriately selecting the developer, positive or negative patterns can be formed.

[0445] Based on the foregoing, it can be inferred that the resist composition of the present invention is a non-chemically amplified resist composition. The resist composition of the present invention does not require a base polymer containing acid-instable groups or a photoacid generator as in known chemically amplified resist compositions, and therefore does not suffer from adverse effects caused by acid diffusion (e.g., image blurring), and can resolve fine patterns.

[0446] The resist composition of the present invention is particularly effective in EUV lithography. This is because the resist composition of the present invention has iodine atoms with high absorption capacity for EUV light, and the high-valent iodine compound represented by formula (1) has three carboxylate ligands on one iodine atom that can cause the aforementioned ligand exchange. Therefore, after film formation, crosslinking with carboxyl-containing compounds will occur at a higher density, resulting in a greater difference in dissolution rate between the unexposed and exposed areas compared to using only other high-valent iodine compounds, i.e., a greater dissolution contrast. In other words, the resist composition of the present invention can achieve high sensitivity, high resolution, and low LWR by virtue of these characteristics.

[0447] In contrast, other high-valent iodine compounds (iodine (III) compounds) represented by formulas (4) and (5) have only 1 to 2 carboxylate ligands on the same iodine atom that can cause the aforementioned ligand exchange. Therefore, during film formation, cross-linking of carboxyl-containing compounds (polymers, monomers) does not occur or is difficult to occur. With only iodine (III) compounds, it is not easy to achieve high sensitivity, high resolution and low LWR.

[0448] Regarding resist compositions for EUV lithography capable of forming fine patterns, there have been reports of metal resists with tin compounds as the main component, which have a similar high absorption capacity for EUV light as iodine atoms (e.g., Patent Document 2). However, as mentioned above, such metal resists suffer from many problems, including insufficient solubility in solvents, poor storage stability, and defects caused by etching residues due to the presence of metal elements. On the other hand, the resist composition of the present invention does not use metal elements, thus it is more advantageous than metal resists in terms of defects and does not have the problem of solubility in solvents. Furthermore, the resist composition of the present invention is applicable to both positive and negative modes, thus having a wide range of applications. For example, in the contact hole formation step, metal resists implemented with negative development require a reversal process after the pillar pattern is formed, while positive resists do not require such a step. Therefore, from the viewpoint of process simplicity, the resist composition of the present invention can be considered more useful than metal resists.

[0449] Japanese Patent Application Publication Nos. 2015-180928 and 2018-95853 disclose resist compositions containing hypervalent iodine compounds as additives, or resist compositions formed by incorporating hypervalent iodine compounds into the polymer backbone of a base polymer. However, these patent documents only describe the properties of the aforementioned resist compositions as improving line edge roughness, without mentioning the possibility of photodecomposition of the hypervalent iodine compounds, or their potential function as materials in non-chemically amplified resist compositions. Furthermore, based on the descriptions and specific examples related to the doping amount, the hypervalent iodine compound is not a main component. Also, Patent Document 3 proposes a positive resist composition using a hypervalent iodine compound, but does not describe the hypervalent iodine compound represented by formula (1) of the present invention, and makes no mention of improving resolution or LWR by using such a compound. Therefore, it is impossible to conceive of a non-chemically amplified resist composition like the one of the present invention, which provides extremely high sensitivity and exhibits excellent resolution, and is highly effective in precision micromachining, based on these patent documents. In other words, the present invention clearly provides novel resist compositions and patterning methods.

[0450] [Layered Body]

[0451] This invention provides a laminate characterized by comprising: a substrate, and a resist film formed from the aforementioned resist composition located on the substrate. In such a laminate comprising a resist film formed from the non-chemically amplified resist composition derived from this invention, the resist film formed from the aforementioned resist composition exhibits extremely high sensitivity and excellent resolution, making it highly effective in precision microfabrication. Furthermore, it is applicable to the formation of any pattern, whether positive or negative, thus having a wide range of applications and high usefulness in resist manufacturing technology.

[0452] At this time, a lower resist film may also be provided between the aforementioned substrate and the aforementioned resist film as needed.

[0453] Furthermore, in the laminate of the present invention, the resist film preferably contains the ligand exchange reaction product of the aforementioned high-valent iodine compound and a carboxyl-containing compound. That is, the laminate can be obtained by forming a resist film derived from the resist composition of the present invention on a substrate, and the aforementioned resist film preferably is formed by ligand exchange between the aforementioned high-valent iodine compound and a carboxyl-containing compound.

[0454] As described above, by removing the byproduct low-molecular-weight carboxylic acids during film formation and subsequent baking steps, the hypervalent iodine compound undergoes a ligand exchange reaction with the carboxyl-containing compound, forming a resist film containing the ligand exchange reaction products (i.e., providing the film-forming body). By completing the ligand exchange, the carboxyl-containing compound becomes a polymer cross-linked with the hypervalent iodine compound. It is preferable to complete the ligand exchange reaction simultaneously with the formation of the resist film in this way.

[0455] [Pattern Formation Method]

[0456] When the resist composition of the present invention is used in the manufacture of various integrated circuits, known photolithography techniques can be employed. For example, a patterning method may include the following steps:

[0457] A resist film is formed on a substrate or on the resist underlayer film of a substrate having a resist underlayer film laminated thereon using the aforementioned resist composition.

[0458] The aforementioned resist film was exposed to high-energy rays, and

[0459] The previously exposed resist film was developed using a developer.

[0460] Hereinafter, the resist underlayer film will also be referred to as the "underlayer film".

[0461] First, the resist composition of the present invention is coated onto a substrate for integrated circuit manufacturing, or onto the lower layer film of a substrate with a stacked lower layer film (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective film, etc.), or onto a substrate for shielding circuit manufacturing, or onto the lower layer film of a substrate with a stacked lower layer film (Cr, CrO, CrON, MoSi2, SiO2, etc.), using a suitable coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, or blade coating, with a coating film thickness of 0.01 to 2 μm. The substrate is then pre-baked on a hot plate at a temperature preferably 60 to 200°C for 10 seconds to 30 minutes, and more preferably 80 to 180°C for 30 seconds to 20 minutes, to form a resist film. Furthermore, the lower layer film refers to the film formed between the substrate and the resist film in a multilayer resist process; there are no particular limitations on the aforementioned lower layer film, and known types can be used.

[0462] Then, the aforementioned resist film is exposed using high-energy radiation. Examples of such high-energy radiation include: ultraviolet rays (gamma rays (436nm), h-rays (405nm), i-rays (365nm), etc.), far ultraviolet radiation, EB, EUV, X-rays, soft X-rays, excimer lasers (KrF excimer lasers, ArF excimer lasers, etc.), gamma rays, and synchrotron radiation. I-rays, KrF excimer lasers, ArF excimer lasers, electron beams, or extreme ultraviolet radiation are preferred. When using ultraviolet radiation, far ultraviolet radiation, EUV, X-rays, soft X-rays, excimer lasers, gamma rays, or synchrotron radiation, the exposure dose should be approximately 1–300 mJ / cm², either directly or using a shielding device to form the desired pattern. 2 And preferably, it should be approximately 10–200 mJ / cm³. 2Irradiation is performed in the manner described above. When using EB (Extracorporeal Electron) radiation, high-energy rays are applied directly or with a shield used to form the desired pattern, with an exposure dose preferably ranging from approximately 0.1 to 2000 μC / cm². 2 And preferably, it is about 0.5 to 1500 μC / cm. 2 The resist composition of the present invention is particularly suitable for fine patterning under high-energy radiation, such as EB or EUV.

[0463] After exposure, PEB should be applied as needed. In this case, it is advisable to apply the PEB on a heated plate or in an oven at 30–150°C for 10 to 30 minutes, or more preferably at 60–120°C for 30 to 20 minutes.

[0464] After exposure or PEB, development and patterning are performed using a developer. Examples of developers used include: alkaline aqueous solutions such as tetramethylammonium hydroxide; 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methyl acetophenone, isopropanol, isoamyl alcohol, n-butanol, n-pentanol, cyclohexanol, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butyl acetate, isoamyl acetate, cyclohexyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, methyl valerate, methyl valerate, methyl crotonate, ethyl crotonate, methyl propionate, ethyl propionate. Organic solvents such as ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, ethyl phenylacetate, benzyl formate, ethyl formate, methyl 3-phenylpropionate, benzyl propionate, 2-phenylethyl acetate, 1-propanol, 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, diacetone alcohol, and 4-methyl-2-pentanol are used. These developers can be used alone or in combination of two or more.

[0465] After development, rinsing should be performed as needed. The rinsing solution should ideally be miscible with the developer and not dissolve the resist film. Suitable solvents include: alcohols with 3 to 10 carbon atoms, ether compounds with 8 to 12 carbon atoms, alkanes, alkenes, alkynes, and aromatic solvents with 6 to 12 carbon atoms. Alternatively, water can be used as the rinsing solution instead of an organic solvent.

[0466] By performing rinsing, the collapse of the resist pattern and the occurrence of defects can be reduced. Furthermore, rinsing is not necessary; by not performing rinsing, the amount of solvent used can be reduced.

[0467] The resist composition of the present invention, as described above, utilizes the difference in solubility between exposed and unexposed areas during exposure to form positive or negative patterns. Therefore, a developer can be used that dissolves the exposed areas but not the unexposed areas, and vice versa. Thus, the pattern forming method of the present invention, by appropriately selecting the developer, can form positive or negative patterns, and is therefore widely applicable to the formation of various fine patterns.

[0468] Example

[0469] The present invention will be specifically described below with examples of synthesis, embodiments and comparative examples, but the present invention is not limited to the following embodiments.

[0470] [1] High-valent iodine (V) compounds

[0471] The high-valent iodine compounds used in the examples are represented by the following formulas (I-1) to (I-2).

[0472] [Chemistry 161]

[0473]

[0474] The high-valent iodine compound represented by formula (I-1) was synthesized with reference to Heterocycles, 2021, 103, 694. The high-valent iodine compound represented by formula (I-2) was synthesized with reference to J. Am. Chem. Soc., 1991, 113, 7277.

[0475] [2] Polymer synthesis

[0476] The monomers a-1 to a-3, b-1 to b-3, c-1, and c-2 used in the synthesis of the polymer are described below.

[0477] [Chemistry 162]

[0478]

[0479] [Chemistry 163]

[0480]

[0481] [Chemistry 164]

[0482]

[0483] [Synthetic Example 2-1] Synthesis of Polymer P-1

[0484] Under nitrogen atmosphere, monomer a-1 (56g), monomer b-1 (105g), V-601 (manufactured by Fujifilm and Koimitsu Chemical Co., Ltd.) 5.4g, and MEK (180g) were measured in a flask to prepare a monomer-polymerization initiator solution. In another flask conditioned under nitrogen atmosphere, MEK (55g) was measured, and the mixture was heated to 80°C with stirring. The aforementioned monomer-polymerization initiator solution was then added dropwise over 4 hours. After the addition was complete, the temperature of the polymerization solution was maintained at 80°C and stirred continuously for 2 hours, then cooled to room temperature. The resulting polymerization solution was added dropwise to 4000g of vigorously stirred hexane, and the precipitated polymer was filtered and separated. The obtained polymer was further washed twice with hexane (1200g) and then vacuum dried at 50°C for 20 hours to obtain a white powder polymer P-1 (yield 155g, 96% yield). The Mw of polymer P-1 was 7700, and the Mw / Mn ratio was 1.82. In addition, Mw is the standard polystyrene conversion value determined by GPC using THF as a solvent.

[0485] [Chemistry 165]

[0486]

[0487] [Synthetic Examples 2-2 to 2-10] Synthesis of Polymers P-2 to P-10

[0488] By changing the types and blending ratios of the monomers, the polymers shown in Table 1 below were synthesized using the same method as in Synthesis Example 1.

[0489] [Table 1]

[0490]

[0491]

[0492] [3] Preparation of the resist composition

[0493] [Examples 1-1 to 1-22, Comparative Examples 1-1 to 1-4]

[0494] High-valent iodine compounds, other high-valent iodine compounds, and polymers were dissolved in a solvent containing 0.01% by mass of a surfactant (PF-636, manufactured by OMNOVA) according to the compositions shown in Table 2 below. The resulting solutions were filtered through a 0.2 μm Teflon (registered trademark) filter to obtain resist compositions (R-01 to R-22) and comparative resist compositions (CR-01 to CR-02). Furthermore, polymers, photoacid generators, and sensitivity modifiers were dissolved in a solvent containing 0.01% by mass of a surfactant (PF-636, manufactured by OMNOVA) according to the compositions shown in Table 3 below. The resulting solutions were filtered through a 0.2 μm Teflon (registered trademark) filter to obtain comparative resist compositions (CR-03 to CR-04).

[0495] [Table 2]

[0496]

[0497]

[0498] [Table 3]

[0499]

[0500] In Tables 2 and 3, the other high-valent iodine compound O-1, carboxyl-containing compounds m-1 to m-6, photoacid generator PAG-1, sensitivity modifier Q-1, and solvents are described below.

[0501] [Chemistry 166]

[0502]

[0503] [Chemistry 167]

[0504]

[0505] [Chemistry 168]

[0506]

[0507] [Chemistry 169]

[0508]

[0509] Solvent: PGMEA (Propylene Glycol Monomethyl Ether Acetate)

[0510] AcOH (acetic acid)

[0511] HBM (methyl 2-hydroxyisobutyrate)

[0512] PA (propionic acid)

[0513] GBL (γ-butyrolactone)

[0514] [4] Evaluation of EUV lithography (line and spacing patterns, positive tone development)

[0515] [Examples 2-1 to 2-22, Comparative Examples 2-1 to 2-4]

[0516] Each resist composition (R-01 to R-22, CR-01 to CR-04) was spin-coated onto a Si substrate containing Shin-Etsu Chemical Co., Ltd. silicon-containing spin-coated hard shielding SHB-A940 (silicon content 43% by mass) with a film thickness of 20 nm. A pre-baking (PAB) process was then performed on a heated plate at the temperatures listed in Table 4 for 60 seconds to obtain a resist film with a thickness of 40 nm. A 36 nm line-to-spacing (LS) 1:1 pattern was then exposed using an ASML EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9, 90-degree dipole illumination). A PEB process was then performed on a heated plate at the temperatures listed in Table 4 for 60 seconds, followed by development with the developer listed in Table 4 for 30 seconds to form an LS pattern with a spacing width of 18 nm and a pitch of 36 nm.

[0517] The obtained resist pattern was evaluated as follows. The results are shown in Table 4.

[0518] [Sensitivity Evaluation]

[0519] The aforementioned LS pattern was observed using a Hitachi Advanced Technology Co., Ltd. (GAD) CG-6300 measuring SEM, and the optimal exposure Eop (mJ / cm²) for obtaining an LS pattern with a spacing width of 18nm and a pitch of 36nm was determined. 2 And make it a sensitivity.

[0520] [LWR Evaluation]

[0521] The dimensions of 10 points on an LS pattern obtained by exposure to the optimal amount of light along the length direction of the pitch width were measured using a Hitachi Advanced Technology Co., Ltd. The LWR was defined as three times the standard deviation (σ) obtained from the results (3σ). The smaller this value, the more uniform and less rough the pitch width pattern can be obtained.

[0522] [Evaluation of Extreme Resolution]

[0523] Using a Hitachi Advanced Technologies (AGT) CG-6300 long-range SEM, the limiting linewidth (nm) obtained by progressively increasing the exposure amount to form the aforementioned LS pattern was determined, and this limiting linewidth was set as the limiting resolution (nm). The smaller this value, the better the limiting resolution, and the finer the pattern can be formed.

[0524] [Table 4]

[0525]

[0526] Developer: nBA (Butyl acetate)

[0527] CHA (cyclohexyl acetate)

[0528] TMAH (2.38% by mass tetramethylammonium hydroxide aqueous solution)

[0529] [5] Evaluation of EUV lithography (line and spacing patterns, negative tone development)

[0530] [Examples 3-1 to 3-22, Comparative Examples 3-1 to 3-4]

[0531] Each resist composition (R-01 to R-22, CR-01 to CR-04) was spin-coated onto a Si substrate containing Shin-Etsu Chemical Co., Ltd. silicon-containing spin-coated hard shielding SHB-A940 (silicon content 43% by mass) with a film thickness of 20 nm. A pre-baking (PAB) process was then performed on a heated plate at the temperature described in Table 5 for 60 seconds to obtain a resist film with a thickness of 40 nm. A 36 nm line-to-spacing (LS) 1:1 pattern was then exposed using an ASML EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9, 90-degree dipole illumination). After exposure, a baking (PEB) process was performed on a heated plate at the temperature described in Table 5 for 60 seconds, followed by development with the developer described in Table 5 for 30 seconds to form an LS pattern with a spacing width of 18 nm and a pitch of 36 nm.

[0532] The obtained resist patterns were evaluated as follows. The results are shown in Table 5.

[0533] [Sensitivity Evaluation]

[0534] The aforementioned LS pattern was observed using a Hitachi Advanced Technology Co., Ltd. (GAD) CG-6300 measuring SEM, and the optimal exposure Eop (mJ / cm²) for obtaining an LS pattern with a spacing width of 18nm and a pitch of 36nm was determined. 2 And make it a sensitivity.

[0535] [LWR Evaluation]

[0536] The dimensions of 10 points on an LS pattern obtained by exposure to the optimal amount of light along the length direction of the pitch width were measured using a Hitachi Advanced Technology Co., Ltd. The LWR was defined as three times the standard deviation (σ) obtained from the results (3σ). The smaller this value, the more uniform and less rough the pitch width pattern can be obtained.

[0537] [Evaluation of Extreme Resolution]

[0538] Using a Hitachi Advanced Technologies (AG) CG-6300 long-range SEM, the limiting linewidth (nm) obtained by progressively increasing the exposure amount to form the aforementioned LS pattern was determined, and this limiting linewidth was set as the limiting resolution (nm). The smaller this value, the better the limiting resolution, and the finer the pattern can be formed.

[0539] [Table 5]

[0540]

[0541] As shown in Tables 4 and 5, the resist composition of the present invention exhibits excellent sensitivity, LWR, and resolution during EUV exposure for the formation of line and spacing patterns, regardless of whether it is positive or negative tone development.

[0542] [6] Evaluation of EUV lithography (contact hole pattern)

[0543] [Examples 4-1 to 4-22, Comparative Examples 4-1 to 4-4]

[0544] Each resist composition (R-01 to R-22, CR-01 to CR-04) was spin-coated onto a Si substrate with a silicon-containing spin-coated hard shielding material (SHB-A940, 43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd., having a film thickness of 20 nm. The substrate was then pre-baked (PAB) for 60 seconds at the temperatures listed in Table 6 using a heated plate to obtain a resist film with a thickness of 50 nm. The resist film was then exposed using an ASML EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9 / 0.6, quadrupole illumination, wafer-scale hole pattern shielding with a pitch of 64 nm and a +20% offset). The film was then baked (PEB) for 60 seconds at the temperatures listed in Table 6 using a heated plate, followed by development for 30 seconds using the developer listed in Table 6 to obtain a hole pattern with a size of 32 nm.

[0545] The obtained resist patterns were evaluated as follows. The results are shown in Table 6.

[0546] [Sensitivity Evaluation]

[0547] The aforementioned contact hole pattern was observed using a Hitachi Advanced Technology Co., Ltd. (HIT) CG-6300 SEM, and the optimal exposure value Eop (mJ / cm²) for obtaining a hole pattern with a size of 32nm was determined. 2 ).

[0548] [CD Uniformity (CDU) Evaluation]

[0549] The dimensions of 50 hole patterns obtained by irradiation with the optimal exposure were measured, and the standard deviation (σ) of the results was defined as three times the value of 3σ (CDU). The smaller this value, the more uniform the hole diameter of the pattern can be obtained.

[0550] [Evaluation of Extreme Resolution]

[0551] Using a Hitachi Advanced Technologies (AGT) CG-6300 long-range SEM, the limiting aperture diameter (nm) was determined by progressively decreasing the exposure amount to form the aforementioned aperture pattern, starting from the optimal exposure. This value was then set as the limiting resolution (nm). The smaller this value, the better the limiting resolution, and the more finer the aperture pattern can be formed.

[0552] [Table 6]

[0553]

[0554] As shown in Table 6, the resist composition of the present invention exhibits excellent sensitivity, CDU, and resolution during contact hole pattern formation under EUV exposure.

[0555] This specification contains the following specifications.

[0556] [1]: An anti-corrosion composition characterized by containing a high-valent iodine compound represented by formula (1), a carboxyl-containing compound, and a solvent.

[0557] [Chemistry 170]

[0558]

[0559] In the formula, m is an integer from 0 to 2, n is an integer from 0 to 4 when m is 0, an integer from 0 to 6 when m is 1, and an integer from 0 to 8 when m is 2. R 1 R 2 R 3 Each group consists of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. R 1 R 2 R 3 They can also bond together to form a loop. R 4 It is a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. When n is 2 or more, each R 4 They can be the same or different. Also, multiple R's... 4 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. R 5 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms. *1 and *2 represent atomic bonds of carbon atoms in the aromatic ring in the formula. However, *1 and *2 are bonded to adjacent carbon atoms on the aromatic ring.

[0560] [2]: The resist composition of [1], wherein the aforementioned carboxyl-containing compound is either or both of a polymer containing a repeating unit represented by formula (2) and a compound represented by formula (3).

[0561] [Chemistry 171]

[0562]

[0563] In the formula, R A It can be a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group. X A It is a single bond, phenylene, naphthylene, or *-C(=O)-OX A1 -. X A1 It is a saturated hydrocarbon group, phenylene group, or naphthylene group having 1 to 10 carbon atoms, and the saturated hydrocarbon group may also contain a hydroxyl group, ether bond, ester bond, or lactone ring. * indicates an atomic bond with a carbon atom in the main chain. p is 1, 2, 3, or 4. R 31 R is a p-valent hydrocarbon group with 1 to 40 carbon atoms or a p-valent heterocyclic group with 2 to 40 carbon atoms; when p is 2, R 31 It can also be an ether bond, carbonyl group, azo group, thioether bond, carbonate bond, carbamate bond, sulfinyl group, or sulfonyl group. Furthermore, some or all of the hydrogen atoms in the aforementioned p-valent hydrocarbon group or p-valent heterocyclic group can be substituted by a group containing a heteroatom, and a portion of the -CH2- group in the aforementioned p-valent hydrocarbon group can also be substituted by a group containing a heteroatom. R 32 It is a single bond or a hydrocarbon group with 1 to 20 carbon atoms, and some or all of the hydrogen atoms of the hydrocarbon group can be replaced by a group containing a heteroatom, and part of the -CH2- of the hydrocarbon group can also be replaced by a group containing a heteroatom. When p is 2, 3 or 4, each R 32 They can be the same or different.

[0564] [3]: The resist composition such as [1] or [2] further contains at least one of the high-valent iodine compounds represented by formula (4) or (5).

[0565] [Chemistry 172]

[0566]

[0567] In the formula, m1 and m2 are integers from 0 to 2. n1 is an integer from 0 to 4 when m1 is 0, an integer from 0 to 6 when m1 is 1, and an integer from 0 to 8 when m1 is 2. When m2 is 0, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 5, satisfying 1 ≤ (n2 + n3) ≤ 6. When m2 is 1, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 7, satisfying 1 ≤ (n2 + n3) ≤ 8. When m2 is 2, n2 is an integer from 1 to 3, and n3 is an integer from 0 to 9, satisfying 1 ≤ (n2 + n3) ≤ 10. R 41 A hydrocarbon group consisting of 1 to 10 carbon atoms, which may also contain heteroatoms. R 42 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. When n1 is 2 to 6, each R 42 They can be the same or different. Also, multiple R's... 42 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to. R 43 It is a carbonyl group, or a hydrocarbon group with 1 to 10 carbon atoms that may also contain heteroatoms. *3 and *4 represent atomic bonds of the carbon atoms in the aromatic ring in the formula. However, *3 and *4 must be bonded to adjacent carbon atoms on the aromatic ring. R 51 and R 52 Each group consists independently of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 10 carbon atoms. Also, R 51 and R 52 They can also bond to each other and form rings together with the carbon atoms they are bonded to and the atoms between those carbon atoms. When n2 is 2 to 3, each R 51 and R 52 They can be the same or different. R 53 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain halogen atoms or heteroatoms. When n3 is 2 to 9, each R 53 They can be the same or different. Also, multiple R's... 53 They can also bond to each other and form rings together with the carbon atoms of the aromatic rings they are bonded to.

[0568] [4]: A laminated body characterized by having:

[0569] substrate, and

[0570] The substrate has a resist film consisting of a resist composition as described in any of [1] to [3].

[0571] [5]: As in [4], a laminated body, wherein a lower resist film is provided between the aforementioned substrate and the aforementioned resist film.

[0572] [6]: such as [4] or [5], wherein the aforementioned resist film contains the ligand exchange reaction product of the aforementioned high-valent iodine compound and the carboxyl-containing compound.

[0573] [7]: A method for forming a pattern, characterized by comprising the following steps:

[0574] A resist film is formed on a substrate or on the resist underlayer of a substrate having a resist composition as described in any of [1] to [3].

[0575] The aforementioned resist film was exposed to high-energy rays, and

[0576] The previously exposed resist film was developed using a developer.

[0577] [8]: The pattern forming method as in [7], wherein the aforementioned high-energy rays are i-rays, KrF excimer lasers, ArF excimer lasers, electron beams or extreme ultraviolet rays.

[0578] [9]: The pattern forming method as in [7] or [8], wherein the aforementioned developing solution is used to dissolve the exposed portion but not the unexposed portion.

[0579]

[10] : The pattern forming method, such as [7] or [8], wherein the aforementioned developer is used to dissolve the unexposed portion and not the exposed portion.

[0580] Furthermore, the present invention is not limited to the embodiments described above. The embodiments described above are illustrative examples, and those having substantially the same structure and performing the same effects as the technical concept described in the claims of the present invention are all intended to be included within the technical scope of the present invention.

Claims

1. A resist composition, characterized by A high-valent iodine compound represented by the following formula (1), a carboxyl group-containing compound, and a solvent; wherein m is an integer of 0 to 2, n is an integer of 0 to 4 when m is 0, an integer of 0 to 6 when m is 1, and an integer of 0 to 8 when m is 2; R 1 , R 2 , R 3 are each independently a halogen atom or a hydrocarbon group having 1 to 10 carbons which can also contain a hetero atom; R 1 , R 2 , R 3 may be bonded to each other and form a ring; R 4 is a halogen atom or a hydrocarbon group having 1 to 40 carbons which can also contain a hetero atom; when n is 2 or more, the R 4 may be the same or different; further, a plurality of R 4 may be bonded to each other and form a ring together with the carbon atoms of the aromatic ring to which they are bonded; R 5 is a carbonyl group or a hydrocarbylene group having 1 to 10 carbons which can also contain a hetero atom; *1 and *2 indicate atomic bonds to the carbon atoms of the aromatic ring in the formula; however, *1 and *2 are bonded to adjacent carbon atoms on the aromatic ring.

2. The resist composition according to claim 1, wherein, The carboxyl group-containing compound is either one or both of a polymer containing a repeating unit represented by the following formula (2) and a compound represented by the following formula (3); wherein R A is a hydrogen atom, a halogen atom, a methyl group or a trifluoromethyl group; X A is a single bond, a phenylene group, a naphthylene group or a *-C(=O)-O-X A1 - group; X A1 is a saturated hydrocarbylene group having 1 to 10 carbon atoms, a phenylene group or a naphthylene group, and the saturated hydrocarbylene group can also have a hydroxyl group, an ether bond, an ester bond or a lactone ring; * indicates an atomic bond to a carbon atom of the main chain; p is 1, 2, 3 or 4; R 31 is a p-valent hydrocarbon group having 1 to 40 carbon atoms or a p-valent heterocyclic group having 2 to 40 carbon atoms, and when p is 2, R 31 may also be an ether bond, a carbonyl group, an azo group, a sulfide bond, a carbonate bond, a carbamate bond, a sulfinyl group or a sulfonyl group; further, a part or all of the hydrogen atoms of the p-valent hydrocarbon group or the p-valent heterocyclic group can be substituted with a heteroatom-containing group, and a part of the -CH2- of the p-valent hydrocarbon group can also be substituted with a heteroatom-containing group; R 32 is a single bond or a hydrocarbylene group having 1 to 20 carbon atoms, and a part or all of the hydrogen atoms of the hydrocarbylene group can be substituted with a heteroatom-containing group, and a part of the -CH2- of the hydrocarbylene group can also be substituted with a heteroatom-containing group; when p is 2, 3 or 4, each R 32 may be the same or different.

3. The resist composition according to claim 1, further containing at least one of high-valent iodine compounds represented by the following formula (4) or (5). wherein m1 and m2 are integers of 0 to 2, n1 is an integer of 0 to 4 when m1 is 0, an integer of 0 to 6 when m1 is 1, and an integer of 0 to 8 when m1 is 2; n2 is an integer of 1 to 3, n3 is an integer of 0 to 5, and 1 ≤ (n2 + n3) ≤ 6 when m2 is 0; n2 is an integer of 1 to 3, n3 is an integer of 0 to 7, and 1 ≤ (n2 + n3) ≤ 8 when m2 is 1; n2 is an integer of 1 to 3, n3 is an integer of 0 to 9, and 1 ≤ (n2 + n3) ≤ 10 when m2 is 2; R 41 is a halogen atom or a hydrocarbon group having 1 to 10 carbon atoms which can also contain a hetero atom; R 42 is a halogen atom or a hydrocarbon group having 1 to 40 carbon atoms which can also contain a hetero atom; when n1 is 2 to 6, each R 42 may be the same or different; further, a plurality of R 42 may be bonded to each other and form a ring together with the carbon atoms of the aromatic ring to which they are bonded; R 43 is a carbonyl group or an alkylene group having 1 to 10 carbon atoms which can also contain a hetero atom; *3 and *4 represent atomic bonds to the carbon atoms of the aromatic ring in the formula; however, *3 and *4 must be bonded to adjacent carbon atoms on the aromatic ring; R 51 and R 52 are each independently a halogen atom or a hydrocarbon group having 1 to 10 carbon atoms which can also contain a hetero atom; further, R 51 and R 52 may be bonded to each other and form a ring together with the carbon atoms to which they are bonded and the atoms between the carbon atoms; when n2 is 2 to 3, each R 51 and R 52 may be the same or different; R 53 is a halogen atom or a hydrocarbon group having 1 to 40 carbon atoms which can also contain a hetero atom; when n3 is 2 to 9, each R 53 may be the same or different; further, a plurality of R 53 may be bonded to each other and form a ring together with the carbon atoms of the aromatic ring to which they are bonded.

4. A laminate characterized by comprising: a substrate, and an resist film of a film-forming body of the resist composition according to any one of claims 1 to 3 on the substrate.

5. The laminate according to claim 4, wherein Further comprising a resist underlayer film between the substrate and the resist film.

6. The laminate according to claim 4, wherein The resist film contains a ligand exchange reaction product of the high-valent iodine compound and the carboxyl group-containing compound.

7. A pattern forming method characterized by comprising the steps of: forming a resist film on a substrate or a resist underlayer film of a substrate having the resist underlayer film using the resist composition according to any one of claims 1 to 3, exposing the resist film to a high-energy ray, and developing the exposed resist film using a developer.

8. The pattern forming process according to claim 7, wherein The high-energy ray uses an i-ray, a KrF excimer laser, an ArF excimer laser, an electron beam, or an extreme ultraviolet ray.

9. The pattern forming process according to claim 7, wherein The developer dissolves the exposed portion and does not dissolve the unexposed portion.

10. The pattern forming process according to claim 8, wherein The developer dissolves the exposed portion and does not dissolve the unexposed portion.

11. The pattern forming process according to claim 7, wherein The developer dissolves the unexposed portion and does not dissolve the exposed portion.

12. The pattern forming process according to claim 8, wherein The developer dissolves the unexposed portion and does not dissolve the exposed portion. The developer dissolves the unexposed portion and does not dissolve the exposed portion.

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