KR-102960763-B1 - Radiation-sensitive resin composition and pattern formation method

Abstract

A radiation-reducing resin composition and a pattern forming method are provided, which can form a resist film having a sufficient level of sensitivity or CDU performance even when next-generation technology is applied. The radiation-reducing resin composition comprises a resin having a structural unit represented by the following formula (1), one or more onium salts having an organic acid anion portion and an onium cation portion, and a solvent, wherein at least a portion of the organic acid anion portion in the onium salt has an iodine-substituted aromatic ring structure. (In the above formula (1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halide group having 1 to 5 carbon atoms, Y1 is a divalent linker, and X1 is an acid-dissociable group. n is 0 or 1.)

Inventors

• 마루야마, 겐

Assignees

• 제이에스알 가부시키가이샤

Dates

Publication Date

20260507

Application Date

20211220

Priority Date

20210319

Claims (9)

1. A resin comprising a structural unit represented by the following formula (1), and One or more onium salts comprising an organic acid anion portion and an onium cation portion, and solvent Contains, A radiation-reducing resin composition in which at least a portion of the organic acid anion portion of the above onium salt comprises an iodine-substituted aromatic ring structure. (In the above formula (1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halide group having 1 to 5 carbon atoms, Y1 is a divalent linker, and X1 is an acid-dissociable group. n is 1, and X 1 of the above equation (1) is represented by the following equation (s1) or (s2). (among the above formula (s1), Cy is an aliphatic cyclic group formed with a carbon atom. Ra O1 to Ra O3 each independently represent a hydrogen atom, a substituted or unsubstituted monovalent chain-type saturated hydrocarbon group having 1 to 10 carbon atoms, or a substituted or unsubstituted monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or an aliphatic cyclic structure formed by combining two or more of these, provided that the aliphatic cyclic structure does not form a cross-linked structure. Among the above equation (s2), Cy is synonymous with the above formula (s1). Ra O4 is a substituted or unsubstituted aromatic hydrocarbon group. In the above formulas, * represents all bond losses with oxygen atoms.
2. In paragraph 1, the above onium salt A radioactive acid generator comprising the above organic acid anion portion and the above onium cation portion, and An acid diffusion control agent comprising the above organic acid anion portion and the above onium cation portion, which generates an acid having a higher pKa than the acid generated from the above radioactive acid generator by irradiation with radiation. At least one type selected from the group consisting of, and A radioactive resin composition in which at least one of the organic acid anion portion in the above radioactive acid generator and the organic acid anion portion in the above acid diffusion control agent comprises the above iodine-substituted aromatic ring.
3. A radiation-reducing resin composition according to claim 1 or 2, wherein the organic acid anion portion comprises at least one selected from the group consisting of sulfonate anions, carboxylate anions, and sulfonimide anions.
4. A radiation-reducing resin composition according to claim 1 or 2, wherein the resin further comprises a structural unit having a phenolic hydroxyl group.
5. A radiation-reducing resin composition according to claim 1 or 2, wherein the resin further comprises a structural unit comprising at least one selected from the group consisting of a lactone structure, a cyclic carbonate structure, and a sulfone structure.
6. A radiation-reducing resin composition according to claim 1 or 2, further comprising a high-fluorine content resin having a mass content of fluorine atoms greater than that of the resin.
7. A process of forming a resist film by applying a radiation-sensitive resin composition described in claim 1 or 2 directly or indirectly onto a substrate, and A process for exposing the above resist film, and A process of developing the above-exposed resist film with a developer. A pattern forming method including
8. A pattern forming method according to claim 7, wherein the exposure is performed using extreme ultraviolet rays or electron beams.
9. delete

Description

Radiation-sensitive resin composition and pattern formation method The present invention relates to a radiation-sensitive resin composition and a pattern-forming method. Photolithography technology using a resist composition is utilized for forming fine circuits in semiconductor devices. As a typical procedure, for example, acid is generated by exposure through radiation irradiating a film of the resist composition through a mask pattern, and a resist pattern is formed on a substrate by creating a difference in the solubility of the resin with respect to an alkaline or organic solvent-based developer in the exposed and unexposed areas through a reaction catalyzed by the acid. In the above photolithography technology, pattern miniaturization is promoted by using short-wavelength radiation such as an ArF excimer laser, or by combining this radiation with liquid emulsion lithography. As a next-generation technology, the use of even shorter-wavelength radiation such as electron beams, X-rays, and EUV (extreme ultraviolet) is being pursued, and resist materials containing an acid-generating agent having a benzene ring that increases the absorption efficiency of such radiation are also being considered (Japanese Patent Publication No. 2014-2359). Embodiments of the present invention will be described in detail below, but the present invention is not limited to these embodiments. <Radioactive Resin Composition> The radiation-sensitive resin composition according to the present embodiment (hereinafter also simply referred to as the “composition”) comprises one or more of the specified onium salts, and also comprises a compound and a solvent. Additionally, it comprises a resin as needed. The composition may also include other optional components as long as they do not impair the effects of the present invention. By including the specified onium salt and compound, the radiation-sensitive resin composition can impart a high level of sensitivity and CDU performance to the radiation-sensitive resin composition. <Radiation Insulation> A radioactive resin (hereinafter also simply referred to as "resin") is an aggregate of polymers containing a structural unit (I) (hereinafter also referred to as "base resin"). In addition to the structural unit (I), the base resin may contain a structural unit having a phenolic hydroxyl group or a structural unit imparting a phenolic hydroxyl group by the action of an acid (hereinafter both are referred to as "structural unit (II)"), a structural unit (III) containing a lactone structure, etc. Each structural unit will be described below. (Structural Unit (I)) The structural unit (I) is represented by the following equation (1). (In the above formula (1), R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halide group having 1 to 5 carbon atoms, Y1 is a divalent linker, and X1 is an acid-dissociable group. n is 0 or 1. Among the above formula (1), the alkyl group having 1 to 5 carbon atoms represented by R is preferably a straight-chain or branched-chain alkyl group, and specifically, examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, etc. In the above formula (1), the alkyl halide group having 1 to 5 carbon atoms represented by R may be a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with a halogen atom. Examples of the halogen atoms may include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc., and fluorine atoms are particularly preferred. Suitable linkers for Y1 include divalent hydrocarbon groups that may have substituents, divalent linkers containing heteroatoms, etc., although not specifically limited. The phrase “having a substituent” in a hydrocarbon group means that some or all of the hydrogen atoms in the hydrocarbon group are replaced by a substituent (a group or atom other than a hydrogen atom). The above hydrocarbon group may be an aliphatic hydrocarbon or an aromatic hydrocarbon. Aliphatic hydrocarbon groups refer to hydrocarbon groups that do not possess aromaticity. The aliphatic hydrocarbon group as the divalent hydrocarbon group in the above Y1 may be saturated or unsaturated, and is usually preferably saturated. As the above aliphatic hydrocarbon group, more specifically, examples include straight-chain or branched-chain aliphatic hydrocarbon groups, aliphatic hydrocarbon groups containing rings in their structure, etc. The above straight-chain or branched-chain aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1 to 3. As for straight-chain aliphatic hydrocarbon groups, straight-chain alkylene groups are preferred, specifically methylene groups [ -CH2- ], ethylene groups [-( CH2 ) 2- ], trimethylene groups [-( CH2 ) 3- ], tetramethyle