TW202122448A - Radiation-sensitive resin composition, method for forming resist pattern, polymer, and compound - Google Patents

Abstract

The purpose of the present invention is to provide a radiation-sensitive resin composition that exhibits a good sensitivity to exposure light and an excellent LWR performance and CDU performance, a method for forming resist patterns, a polymer, and a compound that can be used in the preceding. The present invention pertains to a radiation-sensitive resin composition comprising a polymer having a structural unit represented by formula (1) and a radiation-sensitive acid generator. In formula (1), A is an oxygen atom or sulfur atom. m + n is 2 or 3, m is 1 or 2, and n is 1 or 2. X is a C1-20 divalent organic group. R1 is an acid-dissociable group or a polar group.

Description

Radiation-sensitive resin composition, resist pattern forming method, polymer and compound

The present invention relates to a radiation-sensitive resin composition, a method for forming a resist pattern, a polymer and a compound.

The radiation-sensitive resin composition used in microfabrication by lithography is made of ArF excimer laser light (wavelength 193 nm), KrF excimer laser light (wavelength 248 nm) and other extreme ultraviolet and extreme ultraviolet (wavelength). Electromagnetic waves such as ultraviolet, EUV), electron beams, and other charged particle beams are irradiated to generate acid in the exposed part. The chemical reaction using the acid as a catalyst causes the dissolution speed of the exposed part and the unexposed part to the developer solution. Poor, thereby forming a resist pattern on the substrate.

The radiation-sensitive resin composition requires not only good sensitivity to exposure light, but also line width roughness (LWR) performance showing uniformity of line width and line width display with a long period. The deviation of the critical dimension uniformity (Critical Dimension Uniformity, CDU) performance. In response to these requirements, studies have been conducted on the types or molecular structures of polymers, acid generators, and other components used in the radiation-sensitive resin composition (refer to Japanese Patent Laid-Open No. 2009-14815 and Japanese Patent Laid-Open 2013-200560 Bulletin). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2009-14815 [Patent Document 2] Japanese Patent Laid-Open No. 2013-200560

[The problem to be solved by the invention] However, under the current situation where the miniaturization of the resist pattern has progressed to a level of less than 40 nm in line width, the required level of the performance has further increased, and the conventional radiation-sensitive resin composition cannot meet these requirements.

The present invention is completed based on the above situation, and its object is to provide a radiation-sensitive resin composition, a resist pattern forming method, a polymer, and the above that have good sensitivity to exposure light and excellent LWR performance and CDU performance Compounds that can be used in. [Means to solve the problem]

The invention completed to solve the above-mentioned problems is a radiation-sensitive resin composition containing: a polymer having a structural unit represented by the following formula (1) (hereinafter, also referred to as "structural unit (T)") ( Hereinafter, it is also referred to as [A] polymer) and a radiation-sensitive acid generator (hereinafter, also referred to as [B] acid generator).

所述式（1）中，A為氧原子或硫原子。m+n為2或3，m為1或2，n為1或2。X為碳數1～20的二價有機基。R¹ 為酸解離性基或極性基。[化1]

In the formula (1), A is an oxygen atom or a sulfur atom. m+n is 2 or 3, m is 1 or 2, and n is 1 or 2. X is a divalent organic group having 1 to 20 carbons. R ¹ is an acid dissociable group or a polar group.

Another invention completed to solve the problem is a method for forming a resist pattern, including: directly or indirectly applying a radiation-sensitive resin composition to a substrate; And the step of developing the exposed resist film, and the radiation-sensitive resin composition contains [A] polymer and [B] acid generator.

Another invention completed to solve the above-mentioned problem is a [A] polymer having a structural unit (T).

所述式（i）中，A為氧原子或硫原子。m+n為2或3，m為1或2，n為1或2。X為碳數1～20的二價有機基。R¹ 為酸解離性基或極性基。 [發明的效果]Another invention completed to solve the above-mentioned problem is a compound represented by the following formula (i) (hereinafter, also referred to as "compound (i)"). [化2]

In the formula (i), A is an oxygen atom or a sulfur atom. m+n is 2 or 3, m is 1 or 2, and n is 1 or 2. X is a divalent organic group having 1 to 20 carbons. R ¹ is an acid dissociable group or a polar group. [Effects of the invention]

According to the radiation-sensitive resin composition, resist pattern forming method, polymer, and compound of the present invention, a resist pattern with good sensitivity to exposure light and excellent LWR performance and CDU performance can be formed. Therefore, these can be preferably used for semiconductor device manufacturing applications that are expected to be further miniaturized in the future.

＜Radiation-sensitive resin composition＞ This radiation-sensitive resin composition contains [A] a polymer and [B] an acid generator. The radiation-sensitive resin composition may also contain a second larger total mass content ratio of fluorine atoms than [C] acid diffusion controller, [D] solvent, and [A] polymer (also referred to as the first polymer). A polymer (hereinafter, also referred to as "[E] polymer") is a preferable component, and other optional components may be contained within a range that does not impair the effects of the present invention.

By containing the [A] polymer and [B] acid generator, the radiation-sensitive resin composition can form a resist pattern with good sensitivity to exposure light and excellent LWR performance and CDU performance. Although the reason why the radiation-sensitive resin composition has the structure and exerts the effect is not necessarily clear, it can be estimated as follows, for example. That is, it is considered that it is due to the structural unit (T) in the [A] polymer contained in the radiation-sensitive resin composition, thereby improving the sensitivity and also improving the LWR performance and the CDU performance. Hereinafter, each component of this radiation sensitive resin composition is demonstrated.

＜[A] Polymer＞ [A] The polymer is a polymer having a structural unit (T). It is preferable that in addition to the structural unit (T), the [A] polymer also has a structural unit containing an acid-dissociable group (hereinafter, also referred to as "structural unit (I)"), a lactone structure, and a cyclic carbonate A structural unit of a structure, a sultone structure, or a combination of these (hereinafter also referred to as "structural unit (II)"), a structural unit containing an alcoholic hydroxyl group (hereinafter also referred to as "structural unit (III)") , A structural unit containing a phenolic hydroxyl group (hereinafter also referred to as "structural unit (IV)") and the like are preferable optional components. [A] The polymer may have other structural units other than the structural unit (I) to the structural unit (IV). In addition, the structural unit (I) to the structural unit (IV) are structural units other than the structural unit (T). [A] The polymer may have one or two or more of each structural unit. Hereinafter, each structural unit will be described.

[Structural unit (T)] The structural unit (T) is a structural unit represented by the following formula (1). [A] The polymer has a structural unit (T), and a resist pattern with good sensitivity to exposure light and excellent LWR performance and CDU performance can be formed. In addition, when the structural unit (T) has an acid-dissociable group, the acid-dissociable gene in the exposed part is dissociated by the action of acid generated by exposure, and the solubility of the developer in the exposed part and the unexposed part is generated. Differences, whereby a resist pattern can be formed. The "acid dissociable group" refers to a group that substitutes a hydrogen atom of a carboxyl group, and is a group that is dissociated by the action of an acid. "Ring structure" includes alicyclic structure and aromatic ring structure.

[化3]

In the formula (1), A is an oxygen atom or a sulfur atom. m+n is 2 or 3, m is 1 or 2, and n is 1 or 2. X is a divalent organic group having 1 to 20 carbons. R ¹ is an acid dissociable group or a polar group.

As said A, an oxygen atom is preferable. As the m, 1 is preferred, and 1 is preferred as n (that is, 2 is preferred as m+n).

The X is preferably a divalent hydrocarbon group having 1 to 20 carbon atoms, -X ¹ -O- ^{, -X 2} -NH- or -X ³ -OX ⁴ -, for example. The X ¹ , X ² , X ³ and X ⁴ are each independently a divalent hydrocarbon group having 1 to 20 carbons. These hydrocarbon groups may have substituents such as halogen atoms. That is, the ^{X, X 1, X 2,} X 3 and X ⁴ may each independently represent a divalent hydrocarbon group having a carbon number of 1 to 20 halogen atoms and other substituents.

The divalent hydrocarbon groups having 1 to 20 carbons represented by X, X ¹ , X ² , X ³ and X ⁴ are each independently preferably a divalent chain hydrocarbon group having 1 to 4 carbons, and 6 carbons. ~10 divalent alicyclic hydrocarbon group or carbon 6-10 divalent aromatic hydrocarbon group.

Examples of the divalent chain hydrocarbon group having 1 to 4 carbon atoms include alkanediyl groups such as methanediyl, ethanediyl, n-propanediyl, and isopropanediyl; and alkanediyl groups such as ethylenediyl and propylenediyl. Group; Acetylene diyl, propynyl diyl and other alkynyl diyl groups and so on. Examples of the divalent alicyclic hydrocarbon group having 6 to 10 carbon atoms include: monocyclic cycloalkane diyl groups such as cyclohexanediyl group; monocyclic cycloalkene diyl groups such as cyclohexene diyl group; norbornane diyl group Polycyclic cycloalkane diyl group, adamantane diyl group and tricyclodecane diyl group; polycyclic cycloalkene diyl group such as norbornene diyl group and tricyclodecene diyl group, etc. Examples of divalent aromatic hydrocarbon groups having 6 to 10 carbon atoms include aromatic hydrocarbon diyl groups such as benzenediyl, toluene diyl, and naphthalenediyl; aromatic hydrocarbon diyl alkanediyl groups such as benzenediylmethanediyl and the like.

The X is preferably a divalent hydrocarbon group with 1 to 20 carbons, more preferably a chain hydrocarbon group with 1 to 4 carbons, an alicyclic hydrocarbon group with 6 to 10 carbons, and 6 to 10 carbons. The aromatic hydrocarbon groups are particularly preferably methanediyl, cyclohexanediyl, norbornanediyl, adamantanediyl, and benzenediyl. As the ^{divalent hydrocarbon group of X 1} , X ² , X ³ and X ^4, among them, a divalent hydrocarbon group having 1 to 20 carbons is preferable, and a chain hydrocarbon group having 1 to 4 carbons is more preferable.

As the ^{acid dissociable group of R 1} , preferably, a group represented by the following formula (1-1) or formula (1-2) can be cited.

所述式（1-1）中，R^1A 為碳數1～20的一價烴基。R^1B 及R^1C 分別獨立地為碳數1～20的一價有機基，或者表示R^1B 及R^1C 相互結合並與該些所鍵結的碳原子一起構成的環員數3～20的環結構的一部分。*表示與鄰接於所述式（1）的R¹ 的氧原子鍵結的部位。 所述式（1-2）中，Y為-O-或-S-。R^1D 及R^1E 分別獨立地為碳數1～20的一價烴基，或者表示R^1D 及R^1E 相互結合並與該些所鍵結的原子鏈一起構成的環員數4～20的環結構的一部分。*表示與鄰接於所述式（1）的R¹ 的氧原子鍵結的部位。[化4]

In the formula (1-1), R ^1A is a monovalent hydrocarbon group having 1 to 20 carbons. R ^1B and R ^1C are each independently a monovalent organic group having 1 to 20 carbons, or represent a ring with 3 to 20 ring members formed by combining ^{R 1B} and R ^{1C with the carbon atoms to which they are bonded} Part of the structure. * Represents the site bonded to the oxygen atom ^{adjacent to R 1} in the formula (1). In the formula (1-2), Y is -O- or -S-. R ^1D and R ^1E are each independently a monovalent hydrocarbon group having 1 to 20 carbons, or represent a ring structure of 4 to 20 ring members formed by ^{R 1D} and R ^{1E combined with each other and together with these bonded atomic chains} a part of. * Represents the site bonded to the oxygen atom ^{adjacent to R 1} in the formula (1).

^{Examples of the monovalent hydrocarbon group having 1 to 20 carbons represented by R 1A} of the formula (1-1) include, for example, a monovalent chain hydrocarbon group having 1 to 20 carbons, and a monovalent alicyclic ring having 3 to 20 carbons. Formula hydrocarbon group, a monovalent aromatic hydrocarbon group with 6 to 20 carbon atoms, etc.

Examples of monovalent chain hydrocarbon groups having 1 to 20 carbon atoms include alkyl groups such as methyl, ethyl, n-propyl, and isopropyl; alkenyl groups such as vinyl and propenyl; ethynyl, propynyl, etc. Alkynyl and so on. Examples of monovalent alicyclic hydrocarbon groups having 3 to 20 carbon atoms include alicyclic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, norbornyl, and adamantyl; cyclopropenyl , Cyclobutenyl, cyclopentenyl, cyclohexenyl, norbornenyl and other alicyclic unsaturated hydrocarbon groups. Examples of monovalent aromatic hydrocarbon groups having 6 to 20 carbon atoms include aryl groups such as phenyl, tolyl, xylyl, naphthyl, and anthryl; benzyl, phenethyl, naphthylmethyl, and anthryl Methyl and other aralkyl groups.

^{Examples of the monovalent organic group having 1 to 20 carbons represented by R 1B} and R ^1C of the formula (1-1) include the monovalent hydrocarbon group; having a halogen atom, -OH (hydroxyl), and -CO ( Carboxyl), -CN (cyano), -NH ₂ (amine) and other substituents monovalent hydrocarbon groups; including oxacycloalkane structure, oxacycloalkene structure, lactone structure, cyclic carbonate structure, sulfonate Monovalent groups such as monovalent cyclic polar groups such as lactone structures.

Examples of the ring structure having 3 to 20 ring members formed by bonding ^{R 1B} and R ^{1C of} the formula (1-1) include: cyclopropane structure, cyclobutane structure, cyclopentane structure, and cyclohexane Saturated alicyclic structures such as alkane structure, norbornene structure, and adamantane structure; unsaturated alicyclic structures such as cyclopropene structure, cyclobutene structure, cyclopentene structure, cyclohexene structure, norbornene structure; cyclic ether Structure, lactone structure, cyclic carbonate structure, sultone structure and other heterocyclic structures.

Y in the formula (1-2) is -O- or -S-, more preferably -O-. Examples of the monovalent hydrocarbon group having 1 to 20 carbons represented ^{by R 1D} and R ^1E of the formula (1-2) include those with the carbon number of 1 to 20 represented by ^{R 1A of the formula (1-1).} The same group as the monovalent hydrocarbon group.

Examples of the ring structure having 4 to 20 ring members formed by bonding ^{R 1D} and R ^{1E of} the formula (1-2) include an aliphatic heterocyclic structure having 4 to 20 ring members. Examples of the aliphatic heterocyclic structure having 4 to 20 ring members include: oxetane structure, oxolane structure, oxane structure, and other oxetane structures; oxetene Structure, oxolene structure, oxolene structure and other oxoheterocyclic olefin structures; lactone structure, etc.

Examples of the polar group R ¹ include the following (2-1), group (2-2) or (2-3) are represented as preferred. Further, the polar group R ¹ of said R ¹ is an acid solution from the outside of the base group. (2-1) A monovalent organic group _{having -O-, -CO-, -SO 2} -or -NH- between the carbon-carbon bonds constituting the substituted or unsubstituted hydrocarbon group having 2 to 20 carbon atoms ( Excluding those included in (2-3) below). (2-2) A monovalent organic compound having a structure in which one or more hydrogen atoms constituting a substituted or unsubstituted hydrocarbon group with 1 to 20 carbon atoms are substituted by halogen atoms, -OH, -COOH, -CN or -NH ₂ Base (excluding those included in (2-3) below). _{(2-3) There is -O-, -CO-, -SO 2} -or -NH- between the carbon-carbon bonds that constitute a substituted or unsubstituted hydrocarbon group having 2 to 20 carbon atoms, and has the structure A monovalent organic group in which one or more hydrogen atoms of the hydrocarbon group are substituted with halogen atoms, -OH, -COOH, -CN, or -NH _2.

The polar groups represented by (2-1) and (2-3) include, for example, a group having a lactone structure, a group having a cyclic carbonate structure, a group having a sultone structure, and a group having a cyclic structure. A group having a ketone structure, a group having a cyclic ether structure, and the like are preferable. As described above, the monovalent organic group exemplified as the polar group represented by (2-1) and (2-3) may have a choice between the carbon-carbon bonds constituting the hydrocarbon group From the multiple bases exemplified as described above. Moreover, as the polar group represented by said (2-2), the group which has a phenolic hydroxyl group, the group which has an alcoholic hydroxyl group, etc. are mentioned as preferable ones. Furthermore, the monovalent organic group exemplified as the polar group represented by (2-2) may have one or more hydrogen atoms constituting the hydrocarbon group selected from a plurality of groups exemplified as described above. A structure in which multiple groups are substituted.

[Compound (M)] As a monomer that provides the structural unit (T), for example, a compound (M) represented by the following formula (i) (hereinafter, also referred to as "compound (M)"), etc. are mentioned.

所述式（i）中，A為氧原子或硫原子。m+n為2或3，m為1或2，n為1或2。X為碳數1～20的二價有機基。R¹ 為酸解離性基或極性基。[化5]

In the formula (i), A is an oxygen atom or a sulfur atom. m+n is 2 or 3, m is 1 or 2, and n is 1 or 2. X is a divalent organic group having 1 to 20 carbons. R ¹ is an acid dissociable group or a polar group.

As the ^{acid-dissociable group of R 1} , preferably, a group represented by the formula (1-1) or (1-2) can be cited.

In the formula (i), A, X ^{, and R 1} are equal to ^{A, X, and R 1} in the formula (1).

The compound (M) is produced by the cyclization reaction described below during polymerization, thereby forming the structural unit (T).

[化6]

Among the specific examples of the compound (M), specific examples of the compound in which R ¹ is an acid-dissociable group include the compounds described in the following formulas (1-1-1) to (1-1-25), etc. A compound having a group represented by the formula (1-1). Moreover, as a compound which has the group represented by said formula (1-2), the compound etc. which are represented by following formula (1-2-1)-formula (1-2-2) are mentioned.

[化7]

In the compound (M), ^{specific examples of the compound in which R 1} is a polar group include the compounds described in the following formulas (2-1-1) to (2-1-20) as having the above (2- 1) The compound of the group represented. Moreover, as a compound which has the group represented by said (2-2), the compound etc. which are represented by following formula (2-2-1)-formula (2-2-8) are mentioned. Moreover, as a compound which has the group represented by said (2-3), the compound etc. which are represented by following formula (2-3-1)-formula (2-3-3) are mentioned.

[化8]

[化9]

As a structural unit (T), the structural unit etc. which use the said compound as a monomer are mentioned, for example.

The lower limit of the content ratio of the structural unit (T) is preferably 5 mol%, more preferably 10 mol%, and still more preferably 20 mol% with respect to all the structural units constituting the [A] polymer. Preferably, it is 30 mol%. The upper limit of the content ratio is preferably 80 mol%, more preferably 70 mol%, further preferably 60 mol%, and particularly preferably 50 mol%. By setting the content ratio of the structural unit (T) in the above range, the sensitivity of the radiation-sensitive resin composition to exposure light can be further improved, and the LWR performance and CDU performance can be further improved.

[Structural unit (I)] The structural unit (I) is a structural unit other than the structural unit (T), and is a structural unit containing an acid-dissociable group. The "acid dissociable group" refers to a group substituted with a hydrogen atom of a carboxyl group or a phenolic hydroxyl group, and is a group that is dissociated by the action of an acid. Since [A] polymer has an acid-dissociable group in the structural unit (I), the acid-dissociable gene in the exposed part is dissociated by the action of the acid generated by the exposure, and the exposed part and the unexposed part have an effect on the developer There is a difference in solubility, whereby a resist pattern can be formed.

As the structural unit (I), for example, the structural unit represented by the following formula (2-1A), formula (2-1B), formula (2-2A), and formula (2-2B) (hereinafter also referred to as "Structural unit (I-1A), structural unit (I-1B), structural unit (I-2A), structural unit (I-2B)"), etc. Furthermore, in the structural unit (I-1A) to the structural unit (I-2B), -CR ^X R ^Y R ^Z or -CR ^U R ^{V bonded to an oxy oxygen atom derived from a carboxyl group or a phenolic hydroxyl group} (OR ^W ) is an acid dissociable group.

[化10]

In the above formulas (2-1A) and (2-1B), R ^T is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R ^X is a monovalent hydrocarbon group having 1 to 20 carbons. R ^Y and R ^Z are each independently a monovalent hydrocarbon group having 1 to 20 carbons, or an alicyclic ring having 3 to 20 ring members formed by combining ^{R Y} and R ^{Z with each other and the carbon atoms to which they are bonded} Part of the structure.

In the formulas (2-2A) and (2-2B), R ^T is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. R ^U is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbons. R ^V and R ^W are each independently a monovalent hydrocarbon group with 1 to 20 carbon atoms, or are formed by the combination of ^{a carbon atom to which R V} and R ^{W are bonded to R U} and an oxygen atom adjacent to the carbon atom Part of an aliphatic heterocyclic structure with 4-20 ring members.

Examples of the monovalent hydrocarbon group having 1 to 20 carbons represented by R ^X , R ^Y , R ^Z , R ^U , R ^V and R ^W include those represented by ^{R 1A in the formula (1-1).} The same group as the monovalent hydrocarbon group of 1-20.

Examples of the alicyclic structure having 3 to 20 ring members formed by R ^Y and R ^Z being bonded to each other include, for example, the ring member having 3 to 20 ring members formed by bonding R ^1B and R ^{1C of the above formula (1-1).} The alicyclic structure of 20 has the same alicyclic structure, etc.

Examples of the aliphatic heterocyclic structure having 4 to 20 ring members formed by R ^V and R ^W are combined with each other, for example, the ring member formed by ^{R 1E} and R ^{1F of the above formula (1-2) combined with 4} ～20 Aliphatic heterocyclic structure and so on.

As R ^T , a hydrogen atom or a methyl group is preferable from the viewpoint of copolymerization of the monomer providing the structural unit (I). As R ^X , a hydrogen atom, an alkyl group, or an aryl group is preferable. R ^Y and R ^{Z are} preferably an alkyl group or an alicyclic saturated hydrocarbon group. As the structural unit (I), the above-mentioned structural unit (I-1A) is preferred.

As the structural unit (I), for example, a structural unit in which the compound represented by the formula (m-1) to the formula (m-4), and the formula (m-21) described in the examples described later is a monomer is a monomer. . In addition, as the structural unit (I), for example, the structural unit exemplified as the structural unit (I) in Japanese Patent Application Laid-Open No. 2018-013744, and the above-mentioned formula (2-1A) and formula (2- 1B), formula (2-2A) and formula (2-2B) equivalent structural units, etc.

The lower limit of the content ratio of the structural unit (I) is preferably 5 mol%, more preferably 10 mol%, and still more preferably 20 mol% relative to all the structural units constituting the [A] polymer. Preferably, it is 30 mol%. The upper limit of the content ratio is preferably 80 mol%, more preferably 70 mol%, and still more preferably 60 mol%. When the exposure light is ArF excimer laser light, the content ratio is particularly preferable. When the exposure light is EUV, as the lower limit of the content ratio, relative to all the structural units, it is preferably 10 mol%, more preferably 20 mol%. The upper limit of the content ratio is preferably 70 mol%, and more preferably 60 mol%. By setting the content ratio of the structural unit (I) in the above range, the sensitivity of the radiation-sensitive resin composition to exposure light can be further improved, and the LWR performance and CDU performance can be further improved.

[Structural unit (II)] The structural unit (II) is a structural unit other than the structural unit (T) and the structural unit (I), and is a structural unit including a lactone structure, a cyclic carbonate structure, a sultone structure, or a combination of these. Since the [A] polymer has the structural unit (II), it is easy to more moderately adjust the solubility of the [A] polymer to the developer. As a result, the LWR performance and CDU performance of the radiation-sensitive resin composition can be further improved .

As the structural unit (II), for example, the formula (m-5) to the formula (m-11), the formula (m-13), the formula (m-22), and the formula (m -23) The compound represented is a structural unit of a monomer, etc. In addition, as the structural unit (II), for example, the structural unit exemplified as the structural unit (III) in JP 2018-013744 A, and the like can be cited.

As the lower limit of the content ratio of the structural unit (II), relative to all the structural units in the [A] polymer, it is preferably 5 mol%, more preferably 10 mol%, and still more preferably 20 mol%. Preferably, it is 30 mol%. The upper limit of the content ratio is preferably 80 mol%, more preferably 70 mol%, further preferably 60 mol%, and particularly preferably 50 mol%. By setting the content ratio of the structural unit (II) in the above range, it is easy to further moderately adjust the solubility of the [A] polymer in the developer, and as a result, it is possible to further improve the LWR performance and the CDU performance.

[Structural unit (III)] The structural unit (III) is a structural unit other than the structural unit (T), the structural unit (I), and the structural unit (II), and is a structural unit containing an alcoholic hydroxyl group. Since the [A] polymer has the structural unit (III), it is easy to more moderately adjust the solubility of the [A] polymer to the developer. As a result, the LWR performance and CDU performance of the radiation-sensitive resin composition can be further improved .

As the structural unit (III), for example, a structural unit in which the compound represented by the formula (m-12) and the formula (m-17) described in the examples described later is a monomer is a monomer. In addition, as the structural unit (III), for example, the structural unit exemplified as the structural unit (IV) in JP 2018-028574 A, etc. can be cited.

The lower limit of the content ratio of the structural unit (III) is preferably 1 mol%, and more preferably 5 mol% with respect to all the structural units in the [A] polymer. The upper limit of the content ratio is preferably 40 mol%, more preferably 30 mol%, and still more preferably 20 mol%. When the exposure light is ArF excimer laser light, the content ratio is particularly preferable. When the exposure light is EUV, the lower limit of the content ratio is preferably 1 mol%, and more preferably 5 mol% relative to all the structural units. The upper limit of the content ratio is preferably 60 mol%, more preferably 50 mol%, and still more preferably 40 mol%. By setting the content ratio of the structural unit (III) in the above range, it is easy to further moderately adjust the solubility of the [A] polymer in the developer, and as a result, the LWR performance of the radiation-sensitive resin composition can be further improved And CDU performance.

[Structural unit (IV)] The structural unit (IV) is a structural unit other than the structural unit (T), the structural unit (I), the structural unit (II), and the structural unit (III), and is a structural unit containing a phenolic hydroxyl group. The "phenolic hydroxyl group" is not limited to the hydroxyl group directly bonded to the benzene ring, but refers to all the hydroxyl groups directly bonded to the aromatic ring. In the case of using ArF excimer laser light, KrF excimer laser light, EUV, electron beam, etc. as radiation, the [A] polymer has a structural unit (IV), which can further improve the sensitivity to exposure light. In addition, The LWR performance and CDU performance of the radiation-sensitive resin composition can be further improved. As a structural unit (IV), the structural unit etc. which are represented by following formula (P), for example are mentioned.

[化11]

In the formula (P), R ^A is a hydrogen atom, a fluorine atom, methyl or trifluoromethyl. R ^B is a single bond, -O-, -COO- or -CONH-. Ar ² is a group obtained by removing (p+q+1) hydrogen atoms on an aromatic ring from an aromatic hydrocarbon having 6 to 20 ring members. p is an integer of 0-10. When p is 1, R ^C is a monovalent organic group having 1 to 20 carbons or a halogen atom. When p is 2 or more, a plurality of R ^Cs are the same or different from each other and are a monovalent organic group or a halogen atom having 1 to 20 carbons, or ^{two or more of the plurality of R Cs} are combined with each other and are combined with these The bonded carbon chains together constitute a part of a ring structure with 4 to 20 ring members. q is an integer of 1-11. Here, p+q is 11 or less.

As R ^A , a hydrogen atom or a methyl group is preferable, and a hydrogen atom is more preferable from the viewpoint of copolymerization of the monomer providing the structural unit (IV). As R ^B , a single bond or -COO- is preferred, and a single bond is more preferred. Examples of aromatic hydrocarbons providing Ar ² with 6 to 20 ring members include benzene, naphthalene, anthracene, phenanthrene, fused tetrabenzene, and pyrene. Among these, benzene or naphthalene is preferred, and benzene is more preferred.

Examples of the monovalent organic group having 1 to 20 carbons represented by R ^C include: a monovalent hydrocarbon group having 1 to 20 carbons, and the hydrocarbon group contains a divalent hydrocarbon group at the end of the carbon-to-carbon or bonding bond side. A group of a heteroatom group, a group obtained by substituting a part or all of the hydrogen atoms of the hydrocarbon group and the group including the divalent heteroatom-containing group with a monovalent heteroatom-containing group, and the like. As R ^C , a hydrocarbon group is preferable, and an alkyl group is more preferable. Examples of the ring structure having 4 to 20 ring members in which two or more of the plurality of R ^C are bonded to each other include alicyclic structures such as a cyclohexane structure and the like. As p, 0-2 is preferable, 0 or 1 is more preferable, and 0 is still more preferable. As q, 1 to 3 are preferable, and 1 or 2 is more preferable.

As the structural unit (IV), for example, a structural unit in which the compound represented by the formula (m-18) and the formula (m-19) described in the examples described later is a monomer is a monomer. In addition, as the structural unit (IV), for example, the structural unit exemplified as the structural unit (II) in JP 2018-013744 A, etc. can be cited.

The lower limit of the content ratio of the structural unit (IV) is preferably 5 mol%, more preferably 10 mol%, and particularly preferably 20 mol% with respect to all the structural units constituting the [A] polymer. The upper limit of the content ratio is preferably 80 mol%, more preferably 70 mol%, and particularly preferably 60 mol%. By setting the content ratio of the structural unit (IV) within the above range, the LWR performance and CDU performance of the radiation-sensitive resin composition can be further improved.

[Other structural units] As the other structural unit, for example, a structural unit containing a non-acid-dissociable hydrocarbon group, etc. can be cited. Examples of the non-acid-dissociable hydrocarbon group include a monovalent chain hydrocarbon group bonded to an oxy group of -COO-, a monovalent alicyclic hydrocarbon group, and the like. For example, as a structural unit containing a monovalent alicyclic hydrocarbon group, the structural unit etc. which the compound represented by the formula (m-20) described in the Example mentioned later is a monomer, etc. are mentioned. In the case where the [A] polymer has other structural units, the upper limit of the content of the other structural units is preferably 30 mol%, and more preferably 20 mol%. The lower limit of the content ratio is, for example, 1 mol%.

[A] The lower limit of the polystyrene-converted weight average molecular weight (Mw) obtained by gel permeation chromatography (GPC) as the polymer is preferably 2000, more preferably 3000, and still more preferably It is 4000, particularly preferably 5000. The upper limit of the Mw is preferably 30,000, more preferably 20,000, still more preferably 15,000, and particularly preferably 10,000. By setting the Mw of the polymer [A] in the above range, the coating property of the radiation-sensitive resin composition can be improved, and as a result, the LWR performance and the CDU performance can be further improved.

[A] The upper limit of the ratio (Mw/Mn) of the Mw obtained by GPC to the polystyrene-converted number average molecular weight (Mn) of the polymer [A] is preferably 3.00, more preferably 2.50, and still more preferably 2.00 , Particularly preferably 1.85. As the lower limit of the ratio, it is usually 1.00, preferably 1.10.

In addition, the Mw and Mn of the polymer in this specification are values measured by gel permeation chromatography (GPC) based on the following conditions. GPC string: two "G2000HXL", one "G3000HXL" and one "G4000HXL" from Tosoh (stock) Dissolution solvent: tetrahydrofuran Flow rate: 1.0 mL/min Sample concentration: 1.0% by mass Sample injection volume: 100 μL Column temperature: 40℃ Detector: Differential refractometer Standard material: monodisperse polystyrene

As the lower limit of the content ratio of the [A] polymer in all components other than the [D] solvent of the radiation-sensitive resin composition, it is preferably 50% by mass, more preferably 70% by mass, and still more preferably 80% by mass %. [A] One type or two or more types of polymers can be used.

[[A] Synthesis method of polymer] [A] The polymer can be synthesized by, for example, polymerizing monomers that provide each structural unit by a known method.

＜[B] Acid generator＞ [B] The acid generator is a component that generates acid by irradiation with radiation. Examples of radiation include electromagnetic waves such as visible rays, ultraviolet rays, extreme ultraviolet rays, EUV, X-rays, and gamma rays; and charged particle beams such as electron beams and alpha rays. The action of the acid generated from the [B] acid generator can further promote the change in the solubility of the [A] polymer in the radiation-sensitive resin composition to the developer. As a result, the resolution can be further improved. And LWR. The [B] acid generator contained in the radiation-sensitive resin composition may be in the form of a low-molecular compound (hereinafter, also referred to as "[B] acid generator"), or may be used as [A] A form in which a part of a polymer such as a polymer is incorporated, or the form of both may be used.

[B] The acid generator includes, for example, onium salt compounds, N-sulfonyloxyimide compounds, halogen-containing compounds, and diazolone compounds.

Examples of the onium salt compound include sulfonium salt, tetrahydrothiophenium salt, iodonium salt, phosphonium salt, diazonium salt, and pyridinium salt.

Examples of the alumium salt include: triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octylsulfonate, and triphenylsulfonate 2 -Bicyclo[2.2.1]hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, triphenylacumin camphorsulfonate, 4-cyclohexylphenyldiphenylacumene nonafluoro- N-butane sulfonate, 4-methanesulfonyl phenyl diphenyl sulfonate nonafluoro-n-butane sulfonate, triphenyl sulfonate 1,1,2,2-tetrafluoro-6-(1-adamantane carbonyl Oxy)-hexane-1-sulfonate (a compound represented by the formula (B-4) in the examples described later), triphenylaluminum 2-(1-adamantyl)-1,1-difluoro Ethyl sulfonate, triphenyl sulfonate 2-(adamantane-1-ylcarbonyloxy)-1,1,3,3,3-pentafluoropropane-1-sulfonate (the formula of the following examples ( B-3) The compound represented by), triphenyl alumium maleate, etc. In addition, the compounds represented by the formula (B-1) and the formula (B-5) of the examples described later can be cited.

As the tetrahydrothiophenium salt, for example, 1-(4-n-butoxynaphthalene-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1-(4-n-butoxynaphthalene-1-yl) Yl)tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1-(4-n-butoxynaphthalene-1-yl)tetrahydrothiophenium perfluoro-n-octylsulfonate, 1-(4-n-butane Oxynaphthalene-1-yl) tetrahydrothiophenium 2-bicyclo[2.2.1]hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate (formula (B- 2) The compound represented), 1-(4-n-butoxynaphthalene-1-yl)tetrahydrothiophenium camphorsulfonate, 1-(6-n-butoxynaphthalene-2-yl)tetrahydrothiophene Onium nonafluoro-n-butanesulfonate, 1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium nonafluoro-n-butanesulfonate, etc.

Examples of the iodonium salt include diphenyl iodonium trifluoromethanesulfonate, diphenyl iodonium nonafluoro-n-butanesulfonate, diphenyl iodonium perfluoro-n-octane sulfonate, and diphenyl iodonium 2 -Bicyclo[2.2.1]hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, diphenyl iodophor camphorsulfonate, bis(4-tertiary butylphenyl) iodonium nine Fluorine-n-butanesulfonate and so on.

Examples of the N-sulfonyloxyimide compound include N-trifluoromethanesulfonyloxyphthalimide, N-(trifluoromethanesulfonyloxy)-1,8 -Naphthalimide, N-(trifluoromethylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimidine, N-(nonafluoro-n-butyl Sulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide, N-(perfluoro-n-octylsulfonyloxy)-1,8-naphthalene dimethyl Diimines, N-(perfluoro-n-octylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimines, N-(2-bicyclo[2.2.1 ]Hept-2-yl-1,1,2,2-tetrafluoroethylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimidimine, N-(2 - (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] dodecyl) -1,1-difluoroethyl sulfonylurea yloxy) bicyclo [2.2.1] hept-5-ene - 2,3-Dicarboxyimines, N-(camphorsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimines, etc.

Among these compounds, the [B] acid generator is preferably a sulfonium salt or a tetrahydrothiophenium salt, and more preferably the compound represented by the formula (B-1) to (B-5). In addition, as [B] acid generators, for example, those exemplified as [B] acid generators in JP 2018-013744 A, etc. can be cited.

In the case where the [B] acid generator is [B] the acid generator, the lower limit of the content of the [B] acid generator is preferably 0.1 parts by mass relative to 100 parts by mass of the [A] polymer, and more preferably It is 1 part by mass, more preferably 2 parts by mass, particularly preferably 5 parts by mass. The upper limit of the content is preferably 100 parts by mass, more preferably 60 parts by mass, still more preferably 40 parts by mass, and particularly preferably 30 parts by mass. By setting the content of the [B] acid generator in the above range, the sensitivity of the radiation-sensitive resin composition to exposure light can be further improved, and the LWR performance and CDU performance can be further improved. The radiation-sensitive resin composition may contain one or two or more [B] acid generators.

In addition, as the [B] acid generator, a polymer in which the structure of the acid generator is incorporated as a part of the [A] polymer can also be cited.

＜[C] Acid diffusion control body＞ This radiation-sensitive resin composition contains [C] an acid diffusion control body as an optional component. [C] The acid diffusion control body exerts the effect of controlling the diffusion phenomenon of acid generated from the [B] acid generator or the like by exposure in the resist film, and controlling the poor chemical reaction in the non-exposed area. The [C] acid diffusion controller in the radiation-sensitive resin composition may be in the form of a low-molecular compound (hereinafter, also referred to as "[C] acid diffusion controller"), or as [A] A form in which a part of a polymer such as a polymer is incorporated, or it may be in the form of both.

[C] The acid diffusion control agent includes, for example, a photodegradable base that generates light by exposure to light and generates a weak acid. As the photodegradable base, for example, a compound containing a radiation-sensitive onium cation that is decomposed by exposure and an anion of a weak acid, and the like can be cited. The photodegradable base generates a weak acid due to the protons generated by the decomposition of the radiosensitive onium cation and the anion of the weak acid in the exposed portion, so the acid diffusion controllability is reduced. As a photodegradable base, the compound etc. which are represented by formula (C-1)-a formula (C-4) described in the Example mentioned later, etc. are mentioned, for example. In addition, as the [C] acid diffusion control agent, nitrogen-containing compounds can be cited. As this nitrogen-containing compound, the compound etc. which are represented by the formula (C-5) described in the Example mentioned later, etc. are specifically mentioned. As specific examples of [C] acid diffusion control agents other than these photodegradable bases and nitrogen-containing compounds, for example, those exemplified as [D] acid diffusion control agents in Japanese Patent Laid-Open No. 2018-013744, etc. .

When the radiation-sensitive resin composition contains [C] acid diffusion control agent, the lower limit of the content of [C] acid diffusion control agent is preferably 0.1 mass with respect to 100 parts by mass of the polymer component [A] Part, more preferably 0.5 part by mass, and still more preferably 1 part by mass. The upper limit of the content is preferably 20 parts by mass, more preferably 10 parts by mass, and still more preferably 5 parts by mass.

[C] The lower limit of the content of the acid diffusion control agent is preferably 1 mol%, more preferably 5 mol%, and still more preferably 10 mol% relative to 100 mol% of the [B] acid generator . The upper limit of the content ratio is preferably 250 mol%, more preferably 150 mol%, and still more preferably 100 mol%.

By setting the content and the content ratio of the [C] acid diffusion control agent within the above range, the sensitivity of the radiation-sensitive resin composition to exposure light, LWR performance, and CDU performance can be further improved. The radiation-sensitive resin composition may contain one or two or more [C] acid diffusion controllers.

＜[D] Solvent＞ This radiation-sensitive resin composition usually contains [D] solvent. [D] The solvent is not particularly limited as long as it is a solvent that can dissolve or disperse at least the [A] polymer, [B] acid generator, and optional components contained therein.

[D] Solvents include, for example, alcohol-based solvents, ether-based solvents, ketone-based solvents, amide-based solvents, ester-based solvents, and hydrocarbon-based solvents.

Examples of alcohol-based solvents include: aliphatic monoalcohol-based solvents having 1 to 18 carbon atoms such as 4-methyl-2-pentanol; and alicyclic monoalcohol-based solvents having 3 to 18 carbon atoms such as cyclohexanol; Polyol solvents with 2 to 18 carbon atoms such as 1,2-propylene glycol; partial ether solvents with 3 to 19 carbon atoms such as propylene glycol-1-monomethyl ether.

Examples of ether solvents include dialkyl ether solvents such as diethyl ether, cyclic ether solvents such as tetrahydrofuran, and aromatic ring-containing ether solvents such as diphenyl ether.

Examples of ketone solvents include chain ketone solvents such as acetone; cyclic ketone solvents such as cyclohexanone; 2,4-pentanedione, acetonylacetone, acetophenone, and the like.

Examples of amide-based solvents include cyclic amide-based solvents such as N,N'-dimethylimidazolidinone; and chain-like amide-based solvents such as N-methylformamide.

Examples of ester solvents include monocarboxylic acid ester solvents such as ethyl lactate; polyhydric alcohol carboxylic acid ester solvents such as propylene glycol acetate; and polyhydric alcohol partial ether carboxylic acid ester solvents such as propylene glycol monomethyl ether acetate. ; Polycarboxylic acid diester solvents such as diethyl oxalate; lactone solvents such as γ-butyrolactone; carbonate solvents such as dimethyl carbonate, etc.

Examples of hydrocarbon solvents include aliphatic hydrocarbon solvents having 5 to 12 carbon atoms such as n-pentane; aromatic hydrocarbon solvents having 6 to 16 carbon atoms such as toluene.

Among these, ketone-based solvents or ester-based solvents are preferred, cyclic ketone-based solvents, monocarboxylate-based solvents, polyol partial ether carboxylate-based solvents, or lactone-based solvents are more preferred, and cyclic Hexanone, ethyl lactate, propylene glycol monomethyl ether acetate or γ-butyrolactone. The radiation-sensitive resin composition may contain one or more [D] solvents.

The lower limit of the [D] solvent content in the radiation-sensitive resin composition is preferably 50% by mass, more preferably 60% by mass, and still more preferably 70% by mass. The upper limit of the content ratio is preferably 99.9% by mass, more preferably 99.5% by mass, and still more preferably 99% by mass.

[D] The lower limit of the content of the solvent is preferably 100 parts by mass, more preferably 500 parts by mass, and still more preferably 1000 parts by mass relative to 100 parts by mass of the [A] polymer. The upper limit of the content is preferably 20,000 parts by mass, more preferably 15,000 parts by mass, and still more preferably 10,000 parts by mass.

＜[E] Polymer＞ The [E] polymer is a polymer having a larger total mass content of fluorine atoms than the [A] polymer. Compared with the polymer as the base polymer, polymers with higher hydrophobicity tend to exist on the surface of the resist film, and [E] polymer contains more fluorine atoms in total mass than [A] polymer. The larger the ratio, the characteristics due to the hydrophobicity tend to be on the surface of the resist film. In addition, the receding contact angle between the resist film and the immersion medium increases due to the characteristics due to the hydrophobicity. Therefore, the radiation-sensitive resin composition is suitable for the immersion exposure method by containing the [E] polymer, and can form a resist pattern in which the occurrence of defects is suppressed.

[E] The lower limit of the content of the fluorine atom in the polymer is preferably 1% by mass, more preferably 2% by mass, and still more preferably 3% by mass. The upper limit of the mass content ratio is preferably 60% by mass, more preferably 50% by mass, and still more preferably 40% by mass. By setting the total mass content ratio of fluorine atoms in the above-mentioned range, it is possible to more moderately adjust the presence of [E] polymer bias in the resist film. Furthermore, the structure of the polymer can be determined by ¹³ C-nuclear magnetic resonance (NMR) spectroscopy, and the total mass content ratio of fluorine atoms in the polymer can be calculated based on the structure.

When the [E] polymer is a fluorine atom-containing polymer, the form of the fluorine atom in the [E] polymer is not particularly limited, and it may be bonded to any of the main chain, side chain, and terminal. However, it is preferable to have a structural unit that is a structural unit other than the structural unit (T) and contains a fluorine atom (hereinafter, also referred to as "structural unit (F)").

[Structural unit (F)] As a structural unit (F), the structural unit etc. which are represented by following formula (f-1), for example are mentioned.

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In the formula (f-1), R ^J is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group. G is a single bond, an oxygen atom, a sulfur atom, -COO-, -SO ₂ NH-, -CONH- or -OCONH-. R ^K is a monovalent organic group having 1 to 18 carbons containing a fluorine atom.

As said R ^J , a hydrogen atom or a methyl group is preferable from the viewpoint of copolymerization of the monomer which provides a structural unit (F), and a methyl group is more preferable. The G is preferably -COO-, -SO ₂ NH-, -CONH- or -OCONH-, more preferably -COO-.

As the structural unit (F), for example, a structural unit in which the compound represented by the formula (m-14) to the formula (m-16) described in the examples described later is a monomer is a monomer.

The lower limit of the content ratio of the structural unit (F) is preferably 10 mol%, more preferably 20 mol%, and still more preferably 30 mol% with respect to all the structural units constituting the [E] polymer. The upper limit of the content ratio is preferably 100 mol%, more preferably 90 mol%, and still more preferably 85 mol%. By setting the content ratio of the structural unit (F) in the above range, the mass content ratio of the fluorine atoms of the [E] polymer can be further appropriately adjusted.

[E] The polymer preferably has a structural unit containing an acid-dissociable group and/or a structural unit containing an alcoholic hydroxyl group. As the structural unit containing an acid-dissociable group, for example, the structural unit exemplified as the structural unit (I) of the [A] polymer, and the like. As the structural unit containing an alcoholic hydroxyl group, for example, the structural unit exemplified as the structural unit (III) of the [A] polymer, and the like.

The lower limit of the content of the structural unit containing the acid-dissociable group is preferably 5 mol%, and more preferably 10 mol% with respect to all the structural units constituting the [E] polymer. The upper limit of the content ratio is preferably 60 mol%, more preferably 50 mol%, and still more preferably 40 mol%.

The lower limit of the content ratio of the structural unit containing an alcoholic hydroxyl group is preferably 10 mol%, more preferably 15 mol%, and still more preferably 20 mol% relative to all the structural units constituting the [E] polymer. . The upper limit of the content ratio is preferably 60 mol%, more preferably 50 mol%, and still more preferably 40 mol%.

[Other structural units] [E] The polymer may have other structural units within a range that does not impair the effects of the present invention. The content ratio of the other structural unit can be appropriately determined according to the purpose.

[E] The lower limit of Mw obtained by GPC of the polymer is preferably 1,000, more preferably 3,000, still more preferably 4,000, and particularly preferably 5,000. The upper limit of the Mw is preferably 50,000, more preferably 20,000, still more preferably 10,000, and particularly preferably 8,000.

[E] The upper limit of the ratio of the ratio of Mw to Mn (Mw/Mn) obtained by GPC of the polymer of [E] is preferably 5.00, more preferably 3.00, still more preferably 2.50, and particularly preferably 2.00. As the lower limit of the ratio, it is usually 1.00, preferably 1.20.

The lower limit of the content of the [E] polymer is preferably 0.1 parts by mass, more preferably 1 part by mass, and still more preferably 2 parts by mass relative to 100 parts by mass of the [A] polymer. The upper limit of the content is preferably 20 parts by mass, more preferably 10 parts by mass, and still more preferably 7.5 parts by mass. The radiation-sensitive resin composition may contain one or two or more [E] polymers.

[E] The polymer can be synthesized by, for example, polymerizing monomers that provide each structural unit by a known method.

＜Other optional ingredients＞ As other optional components, for example, surfactants and the like can be cited. The radiation-sensitive resin composition may each contain one or two or more other optional components.

＜Preparation method of radiation-sensitive resin composition＞ The radiation-sensitive resin composition can be prepared by combining optional components such as [A] polymer, [B] acid generator, and optionally [C] acid diffusion controller, [D] solvent, [E] polymer, etc. The mixture is mixed at a predetermined ratio, and it is preferably prepared by filtering the obtained mixture with a membrane filter having a pore size of 0.2 μm or less.

The radiation-sensitive resin composition can be used for both positive pattern formation applications using alkaline developers and negative pattern formation applications using organic solvent-containing developers. The radiation-sensitive resin composition can also be preferably used for ArF exposure applications for exposing ArF excimer laser light, EUV exposure applications for exposing extreme ultraviolet (EUV), and electron beam exposure applications for exposing electron beams.

<Method of forming resist pattern> The resist pattern forming method includes a step of directly or indirectly applying the radiation-sensitive resin composition to a substrate (hereinafter, also referred to as "coating step"); The step of exposing the resist film of (hereinafter, also referred to as "exposure step"); and the step of developing the exposed resist film (hereinafter, also referred to as "development step").

According to this resist pattern forming method, since the radiation-sensitive resin composition described above is used, it is possible to form a resist pattern with good sensitivity to exposure light and small LWR and CDU. Hereinafter, each step will be described.

[Coating Step] In this step, the radiation-sensitive resin composition is directly or indirectly applied to the substrate. Thereby, a resist film is formed. Examples of the substrate include conventionally known ones such as silicon wafers, silicon dioxide, and aluminum-coated wafers. In addition, an organic or inorganic antireflection film disclosed in, for example, Japanese Patent Publication No. 6-12452 or Japanese Patent Application Publication No. 59-93448 may be formed on the substrate. Examples of the coating method include spin coating (spin coating), cast coating, roll coating, and the like. After coating, in order to volatilize the solvent in the coating film, pre-baking (prebake, PB) may be performed as needed. The lower limit of the temperature of PB is preferably 60°C, more preferably 80°C. The upper limit of the temperature is preferably 150°C, more preferably 140°C. The lower limit of the PB time is preferably 5 seconds, and more preferably 10 seconds. The upper limit of the time is preferably 600 seconds, more preferably 300 seconds. The lower limit of the average thickness of the formed resist film is preferably 10 nm, and more preferably 20 nm. As the upper limit of the average thickness, it is preferably 1000 nm, more preferably 500 nm.

[Exposure Step] In this step, the resist film formed by the coating step is exposed. This exposure is performed by irradiating exposure light through a photomask (water-proof and other liquid immersion medium as the case may be). As the exposure light, depending on the line width of the target pattern, for example, electromagnetic waves such as visible light, ultraviolet, extreme ultraviolet, EUV (wavelength 13.5 nm), X-rays, and gamma rays; and charged particle beams such as electron beams and alpha rays. Among these, it is preferably extreme ultraviolet, EUV or electron beam, more preferably ArF excimer laser light (wavelength 193 nm), KrF excimer laser light (wavelength 248 nm), EUV or electron beam, and more preferably ArF beam Molecular laser light or EUV. In addition, exposure conditions such as the amount of exposure can be appropriately selected according to the formulation composition of the radiation-sensitive resin composition, the type of additives, the type of exposure light, and the like.

It is preferable to perform Post Exposure Bake (PEB) after the exposure to promote the [A] polymer generated by the acid generated by the exposure in the exposed part of the resist film. Dissociation of the acid dissociable group. With this PEB, the difference in solubility to the developer can be increased between the exposed part and the unexposed part. The lower limit of the temperature of PEB is preferably 50°C, more preferably 80°C. The upper limit of the temperature is preferably 180°C, more preferably 130°C. The lower limit of the PEB time is preferably 5 seconds, more preferably 10 seconds, and still more preferably 30 seconds. The upper limit of the time is preferably 600 seconds, more preferably 300 seconds, and still more preferably 100 seconds.

[Development step] In this step, the exposed resist film is developed. Thereby, a predetermined resist pattern can be formed. Generally speaking, rinse with water or alcohol and other rinsing liquid after development and then dry. The development method in the development step may be alkali development using an alkaline developer, or organic solvent development using a developer containing an organic solvent.

In the case of alkaline development, as the alkaline developer used for development, for example, dissolving sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propyl Amine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethyl ammonium hydroxide (TMAH), pyrrole , Piperidine, choline, 1,8-diazabicyclo-[5.4.0]-7-undecene, 1,5-diazabicyclo-[4.3.0]-5-nonene, etc. An alkaline aqueous solution containing at least one compound, etc. Among these, a TMAH aqueous solution is preferred, and a 2.38% by mass TMAH aqueous solution is more preferred.

In the case of organic solvent development, the organic solvent-containing developer includes organic solvents such as alcohol-based solvents, ether-based solvents, ketone-based solvents, ester-based solvents, and hydrocarbon-based solvents, and solvents containing the organic solvents. . As the organic solvent, for example, one or two or more of the solvents exemplified as the [D] solvent can be cited. Among these, ester-based solvents or ketone-based solvents are preferred. As the ester solvent, an acetate solvent is preferred, and n-butyl acetate is more preferred. As the ketone solvent, a chain ketone is preferred, and 2-heptanone is more preferred. The lower limit of the content of the organic solvent in the developer is preferably 80% by mass, more preferably 90% by mass, still more preferably 95% by mass, and particularly preferably 99% by mass. Examples of components other than the organic solvent in the developer include water and silicone oil.

Examples of the development method include: a method of immersing the substrate in a tank filled with a developer solution for a fixed period of time (dipping method); and a method of performing development by depositing the developer solution on the surface of the substrate using surface tension for a fixed period of time (covering Puddle method); method of spraying developer on the surface of the substrate (spray method); method of continuously spraying developer on the substrate rotating at a fixed speed while scanning the developer ejection nozzle at a fixed speed (dynamic distribution method) Wait.

Examples of patterns formed by this resist pattern forming method include line and space patterns, hole patterns, and the like.

＜Polymer＞ This polymer is a polymer [A] having a structural unit (T) represented by the formula (1). The polymer can be preferably used as a component of the radiation-sensitive resin composition. This polymer is described as the aforementioned [A] polymer.

＜Compounds＞ This compound is the compound (M) represented by the above formula (i). This compound is described as the compound (M). [Example]

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. The measurement methods of various physical properties are shown below.

[Weight average molecular weight (Mw) and number average molecular weight (Mn)] The Mw and Mn of the polymer are obtained by gel permeation chromatography (GPC) using Tosoh (stock) GPC columns (two "G2000HXL", one "G3000HXL" and one "G4000HXL") ), use the following conditions for measurement. In addition, the degree of dispersion (Mw/Mn) is calculated from the measurement results of Mw and Mn. Dissolution solvent: tetrahydrofuran Flow rate: 1.0 mL/min Sample concentration: 1.0% by mass Sample injection volume: 100 μL Column temperature: 40℃ Detector: Differential refractometer Standard material: monodisperse polystyrene

[ ¹³ C-NMR Analysis] The 13C-NMR analysis of the polymer was performed using a nuclear magnetic resonance device ("JNM-Delta400" of JEOL Co., Ltd.).

＜[M] Synthesis of compound (monomer)＞ [Synthesis Example 1] (Synthesis of Compound (M-1)) 20.0 mmol of ethyl 2-(bromomethyl)acrylate, 30.0 mmol of allyl alcohol, 40.0 mmol of triethylamine, and 50 g of ethyl acetate were added to the reaction vessel, and the mixture was stirred at 60°C for 3 hours. Thereafter, the reaction solution was cooled to 30°C or lower, diluted with water, and ethyl acetate was added to perform extraction, and the organic layer was separated. The obtained organic layer was washed with a saturated sodium chloride aqueous solution and then with water. After drying with sodium sulfate, the solvent was distilled off. Purification is performed by column chromatography, whereby the alkoxy derivative is obtained in a good yield.

After adding a mixture of methanol: water (1:1 (mass ratio)) to the alkoxy derivative to make a 1M solution, 18.5 mmol of sodium hydroxide was added, and the reaction was carried out at 50°C for 4 hours. After that, the reaction solution was cooled to 30°C or less, and 1M hydrochloric acid was added to make the system acidic. Ethyl acetate was added for extraction, and the organic layer was separated. The obtained organic layer was washed with a saturated sodium chloride aqueous solution and then with water. After drying with sodium sulfate, the solvent is distilled off to obtain a carboxylic acid derivative with a good yield.

To the carboxylic acid derivative, add 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride 30.0 mmol, 4-dimethylaminopyridine 3.0 mmol, 1 30.0 mmol of -methylcyclopentyl-2-hydroxyacetate and 50 g of dichloromethane were stirred at 50°C for 24 hours. Thereafter, the reaction solution was cooled to 30°C or lower, diluted with water, and dichloromethane was added to perform extraction, and the organic layer was separated. The obtained organic layer was washed with a saturated sodium chloride aqueous solution and then with water. After drying with sodium sulfate, the solvent was distilled off. Purification is performed by column chromatography to obtain a compound represented by the following formula (M-1) (hereinafter, sometimes referred to as "compound (M-1)" or "monomer (M-1)" in a good yield. -1)"). The synthesis scheme of compound (M-1) is shown below.

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[Synthesis example 2-Synthesis example 40] (Synthesis of monomer (M-2)-monomer (M-40)) Except for suitably changing the raw materials and precursors, the compound represented by the following formula (M-2) to formula (M-40) was synthesized in the same manner as in Synthesis Example 1. Hereinafter, the compounds represented by formula (M-2) to formula (M-40) may be described as "compound (M-2)" to "compound (M-40)" or "monomer (M-2), respectively )" ~ "Single (M-40)".

[化14]

[化15]

＜Synthesis of [A] polymer and [E] polymer＞ Among the monomers used in the synthesis of each polymer, monomers other than the monomers (M-1) to (M-40) are shown below. In addition, in the following synthesis examples, unless otherwise specified, parts by mass refers to the value when the total mass of the monomers used is 100 parts by mass, and mole% refers to the value of the monomers used The value when the total number of moles is set to 100 mole%.

[化16]

[Synthesis example 41] (Synthesis of polymer (A-1)) The monomer (M-2) and the monomer (m-5) were dissolved in 2 at a molar ratio of 50/50 (mol %). -In butanone (200 parts by mass), azobisisobutyronitrile (AIBN) (4 mol% relative to 100 mol% of the total monomers used) is added as a starting agent to prepare a monomer Solution. Put 2-butanone (100 parts by mass) in an empty reaction vessel, and after flushing with nitrogen for 30 minutes, the inside of the reaction vessel was set to 80°C, and the monomer solution was added dropwise over 3 hours while stirring. The start of the dropwise addition was taken as the start time of the polymerization reaction, and the polymerization reaction was performed for 6 hours. After the completion of the polymerization reaction, the polymerization solution was water-cooled and cooled to 30°C or less. The cooled polymerization solution was put into methanol (2,000 parts by mass), and the precipitated white powder was separated by filtration. After washing the white powder separated by filtration twice with methanol, it was separated by filtration, and dried at 50° C. for 15 hours to obtain a white powdery polymer (A-1) (yield: 85%). The Mw of the polymer (A-1) was 8,100, and the Mw/Mn was 1.55. In addition, as ^{a result of 13} C-NMR analysis, the content ratio of each structural unit derived from (M-2) and (m-5) was 51.2 mol% and 48.8 mol%, respectively.

[Synthesis Example 42-Synthesis Example 88] (Synthesis of Polymer (A-2)-Polymer (A-48)) Except for using monomers of the types and blending ratios shown in Table 1, Table 2 and Table 3 below, the polymer (A-2) to the polymer (A-48) were synthesized in the same manner as in Synthesis Example 41 . The content ratio (mol %) and physical property values (Mw and Mw/Mn) of each structural unit of the obtained polymer are shown in Tables 1 to 3 below. In addition, the "-" in the following Tables 1 to 3 indicates that the corresponding monomer is not used.

[Table 1] [A] Polymer Provide monomers of structural unit (T) Provide monomers of other structural units Mw Mw/Mn species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) Synthesis Example 41 A-1 M-2 50 51.2 Structural unit (II) m-5 50 48.8 8100 1.55 Synthesis example 42 A-2 M-2 40 39.2 Structural unit (II) m-9 50 51.0 7900 1.49 M-10 10 9.8 Synthesis Example 43 A-3 M-3 40 41.2 Structural unit (II) m-8 50 47.6 7700 1.57 M-6 10 11.2 Synthesis example 44 A-4 M-4 40 39.9 Structural unit (II) m-10 50 50.2 7800 1.55 M-8 10 9.9 Synthesis Example 45 A-5 M-5 40 39.6 Structural unit (II) m-6 50 48.3 8200 1.49 M-7 10 12.1 Synthesis Example 46 A-6 M-1 30 28.5 Structural unit (II) m-7 40 40.9 8300 1.59 M-11 30 30.6 Synthesis Example 47 A-7 M-2 10 10.4 Structural unit (II) m-11 40 39.9 8100 1.65 M-9 50 49.7 Synthesis Example 48 A-8 M-2 30 29.7 Structural unit (II) m-13 50 49.9 8000 1.57 M-13 20 20.4 Synthesis Example 49 A-9 M-3 30 30.1 Structural unit (II) m-7 30 28.4 7500 1.55 M-12 30 31.8 Structural unit (III) m-12 10 9.7 Synthesis Example 50 A-10 M-2 40 41.3 Structural unit (II) m-11 50 50.4 7700 1.60 Other structural units m-20 10 8.3 Synthesis Example 51 A-11 M-15 50 50.6 Structural unit (I) m-1 50 49.4 8000 1.65 Synthesis Example 52 A-12 M-14 50 49.8 Structural unit (I) m-1 40 40.1 8300 1.61 Structural unit (I) m-3 10 10.1 Synthesis Example 53 A-13 M-14 25 24.8 Structural unit (I) m-2 40 38.9 8400 1.57 M-16 25 26.1 Structural unit (I) m-4 10 10.2 Synthesis Example 54 A-14 M-14 40 41.2 Structural unit (I) m-2 40 38.9 7100 1.63 M-20 10 9.4 Structural unit (I) m-4 10 10.5 Synthesis Example 55 A-15 M-18 50 51.1 Structural unit (I) m-1 40 40.8 7900 1.55 Structural unit (I) m-3 10 8.1 Synthesis Example 56 A-16 M-19 50 51.7 Structural unit (I) m-2 50 48.3 8100 1.59 Synthesis Example 57 A-17 M-17 40 40.2 Structural unit (I) m-2 50 49.2 7700 1.58 M-21 10 10.6 Synthesis Example 58 A-18 M-15 40 38.9 Structural unit (I) m-2 50 51.6 7100 1.55 M-22 10 9.5

[Table 2] [A] Polymer Provide monomers of structural unit (T) Provide monomers of structural unit (I) Provide monomers of structural unit (II) Mw Mw/Mn species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) Synthesis Example 59 A-19 M-23 50 52.2 - - - m-5 50 47.8 7300 1.70 Synthesis Example 60 A-20 M-24 50 50.6 m-1 50 49.4 - - - 7800 1.65 Synthesis Example 61 A-21 M-25 50 49.6 m-2 40 38.6 - - - 7700 1.61 m-3 10 11.8 Synthesis Example 62 A-22 M-15 50 50.6 m-1 50 49.4 - - - 8500 1.51 Synthesis Example 63 A-23 M-26 50 51.7 - - - m-8 40 37.6 8200 1.69 M-27 10 10.7 Synthesis example 64 A-24 M-28 50 52.1 m-2 50 47.9 - - - 7900 1.59 Synthesis Example 65 A-25 M-29 50 51.1 - - - m-5 50 48.9 8200 1.63 Synthesis Example 66 A-26 M-30 50 49.3 m-2 50 50.7 - - - 8100 1.67 Synthesis Example 67 A-27 M-31 50 50.7 - - - m-5 50 49.3 7900 1.62 Synthesis Example 68 A-28 M-32 50 51.4 m-2 50 48.6 - - - 7800 1.60 Synthesis Example 69 A-29 M-1 20 21.1 m-2 40 41.3 m-8 40 37.6 7700 1.66 Synthesis Example 70 A-30 M-18 40 39.1 m-2 50 50.6 m-10 10 10.3 7200 1.61 Synthesis Example 71 A-31 M-23 20 20.8 m-1 30 30.1 m-6 50 49.1 8200 1.51 Synthesis Example 72 A-32 M-7 10 11.1 m-2 40 38.6 m-5 50 50.3 7900 1.66 Synthesis Example 73 A-33 M-4 10 9.9 m-2 50 48.4 m-5 40 41.7 7800 1.67 Synthesis Example 74 A-34 M-37 25 26.1 m-1 25 25.2 m-5 50 48.7 8200 1.51 Synthesis Example 75 A-35 M-38 25 25.9 m-1 50 49.6 m-5 25 24.5 8100 1.55 Synthesis Example 76 A-36 M-39 25 22.1 m-1 25 25.8 m-5 50 52.1 5900 1.71 Synthesis Example 77 A-37 M-40 25 21.7 m-1 50 49.7 m-5 25 28.6 5700 1.74

[table 3] [A] Polymer Provide monomers of structural unit (I) Provide monomers of structural unit (II) Provide monomers of structural unit (III) Mw Mw/Mn species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) Synthesis Example 78 A-38 m-1 50 50.9 m-5 50 49.1 - - - 8500 1.61 Synthesis Example 79 A-39 m-1 40 41.1 m-9 50 47.8 - - - 7800 1.59 m-3 10 11.1 Synthesis Example 80 A-40 m-2 40 39.8 m-6 50 49.6 - - - 8100 1.65 m-4 10 10.6 Synthesis Example 81 A-41 m-1 40 41.5 m-11 50 48.7 - - - 8000 1.55 m-3 10 9.8 Synthesis Example 82 A-42 m-1 40 40.9 m-8 50 48.5 - - - 7700 1.69 m-3 10 10.6 Synthesis Example 83 A-43 m-2 50 51.8 m-13 50 48.2 - - - 7600 1.59 Synthesis example 84 A-44 m-2 60 60.7 m-7 30 28.9 m-12 10 10.4 8100 1.61 Synthesis Example 85 A-45 m-2 40 37.8 m-10 50 53.3 - - - 7900 1.62 m-3 10 8.9 Synthesis Example 86 A-46 m-21 50 45.9 m-5 50 54.1 - - - 4500 1.58 Synthesis Example 87 A-47 m-2 50 53.2 m-22 50 46.8 - - - 4200 1.70 Synthesis Example 88 A-48 m-2 50 49.3 m-5 40 44.4 - - - 6200 1.64 m-23 10 6.3

[Synthesis example 89] (Synthesis of polymer (A-49)) The molar ratio of monomer (M-2), monomer (m-2) and monomer (m-18) is 10/40/50 (Mol%) was dissolved in 1-methoxy-2-propanol (200 parts by mass), and AIBN (4 mol%) was added as an initiator to prepare a monomer solution. Put 1-methoxy-2-propanol (100 parts by mass) in the reaction vessel, and after flushing with nitrogen for 30 minutes, the inside of the reaction vessel was set to 80° C., while stirring, the monomer solution was added dropwise over 3 hours. The start of the dropwise addition was taken as the start time of the polymerization reaction, and the polymerization reaction was performed for 6 hours. After the completion of the polymerization reaction, the polymerization solution was water-cooled and cooled to 30°C or less. The cooled polymerization solution was put into hexane (2,000 parts by mass), and the precipitated white powder was separated by filtration. After washing the white powder separated by filtration twice with hexane, it was separated by filtration and dissolved in 1-methoxy-2-propanol (300 parts by mass). Then, methanol (500 parts by mass), triethylamine (50 parts by mass), and ultrapure water (10 parts by mass) were added, and the hydrolysis reaction was carried out at 70° C. for 6 hours while stirring. After the reaction, the residual solvent was distilled off. The obtained solid was dissolved in acetone (100 parts by mass), and added dropwise to water (500 parts by mass) to solidify the resin. The obtained solid was separated by filtration, and dried at 50° C. for 13 hours to obtain a white powdery polymer (A-49) (yield: 80%). The Mw of the polymer (A-49) was 7,800, and the Mw/Mn was 1.58. In addition, as ^{a result of 13} C-NMR analysis, the content of each structural unit derived from (M-2), (m-2), and (m-18) was 9.9 mol%, 38.8 mol%, and 51.3, respectively. Mol%.

[Synthesis Example 90-Synthesis Example 96] (Synthesis of Polymer (A-50)-Polymer (A-56)) The polymer (A-50) to the polymer (A-56) were synthesized in the same manner as in Synthesis Example 89 except for using monomers of the types and blending ratios shown in Table 4 and Table 5 below. The content ratio (mol %) and physical property values (Mw and Mw/Mn) of each structural unit of the obtained polymer are shown in Table 4 and Table 5 below.

[Table 4] [A] Polymer Provide monomers of structural unit (T) Provide monomers of structural unit (I) Provide monomers of structural unit (III) Provide monomers of structural unit (IV) Mw Mw/Mn species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) Synthesis Example 89 A-49 M-2 10 9.9 m-2 40 38.8 - - - m-18 50 51.3 7800 1.58 Synthesis Example 90 A-50 M-33 10 11.2 m-1 40 39.6 - - - m-19 50 49.2 7700 1.67 Synthesis Example 91 A-51 M-34 40 40.3 - - - m-17 30 30.5 m-18 30 29.2 7100 1.77 Synthesis Example 92 A-52 M-35 50 50.8 m-3 40 41.2 m-17 10 8.0 - - - 8100 1.62 Synthesis Example 93 A-53 M-36 50 51.2 m-2 40 39.9 m-17 10 8.9 - - - 8000 1.71

[table 5] [A] Polymer Provide monomers of structural unit (I) Provide monomers of structural unit (III) Provide monomers of structural unit (IV) Mw Mw/Mn species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) Synthesis Example 94 A-54 m-2 50 50.3 - - - m-18 50 49.7 7700 1.77 Synthesis Example 95 A-55 m-1 50 50.7 - - - m-19 50 49.3 7100 1.67 Synthesis Example 96 A-56 m-2 40 41.2 m-17 30 31.2 m-18 30 27.6 7000 1.59

[Synthesis Example 97] (Synthesis of polymer (E-1)) The monomer (m-1) and the monomer (m-16) were dissolved in 2 so that the molar ratio became 20/80 (mol %) -In butanone (200 parts by mass), AIBN (5 mol%) was added as an initiator to prepare a monomer solution. Put 2-butanone (100 parts by mass) in the reaction vessel, and after flushing with nitrogen for 30 minutes, the inside of the reaction vessel was set to 80°C, and the monomer solution was added dropwise over 3 hours while stirring. The start of the dropwise addition was taken as the start time of the polymerization reaction, and the polymerization reaction was performed for 6 hours. After the completion of the polymerization reaction, the polymerization solution was water-cooled and cooled to 30°C or less. After replacing the solvent with acetonitrile (400 parts by mass), hexane (100 parts by mass) was added and stirred to recover the acetonitrile layer, and this operation was repeated three times. The solvent was replaced with propylene glycol monomethyl ether acetate, thereby obtaining a solution of polymer (E-1) (yield: 78%). The Mw of the polymer (E-1) was 6,000, and the Mw/Mn was 1.62. In addition, as ^{a result of 13} C-NMR analysis, the content ratio of each structural unit derived from (m-1) and (m-16) was 19.9 mol% and 80.1 mol%, respectively.

[Synthesis Example 98-Synthesis Example 100] (Synthesis of Polymer (E-2)-Polymer (E-4)) The polymer (E-2) to the polymer (E-4) were synthesized in the same manner as in Synthesis Example 97 except for using monomers of the types and blending ratios shown in Table 6 below. The content ratio (mol %) and physical property values (Mw and Mw/Mn) of each structural unit of the obtained polymer are shown in Table 6 below.

[Table 6] [E] Polymer Provide monomers of structural unit (F) Provide monomers of structural unit (I) Provide monomers of structural unit (III) Mw Mw/Mn species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) species Allocation ratio (mol%) Containing ratio of structural unit (mol%) Synthesis Example 97 E-1 m-16 80 80.1 m-1 20 19.9 - - - 6000 1.62 Synthesis Example 98 E-2 m-15 80 81.9 m-1 20 18.1 - - - 7200 1.77 Synthesis Example 99 E-3 m-14 60 62.3 m-1 40 37.7 - - - 6700 1.79 Synthesis Example 100 E-4 m-14 70 72.3 - - - m-17 30 27.7 6200 1.78

<Preparation of Radiation Sensitive Resin Composition> The components other than [A] polymer and [E] polymer used in the preparation of each radiation-sensitive resin composition are shown below.

[[B] Acid Generator] B-1 to B-5: Compounds represented by the following formulas (B-1) to (B-5)

[化17]

[[C] Acid Diffusion Control Agent] C-1 to C-5: Compounds represented by the following formulas (C-1) to (C-5)

[化18]

[[D]Solvent] D-1: Propylene glycol monomethyl ether acetate D-2: Cyclohexanone D-3: γ-butyrolactone D-4: Ethyl lactate

[Preparation of positive radiation-sensitive resin composition for ArF exposure] [Example 1] [A] polymer (A-1) 100 parts by mass, [B] acid generator (B-4) 14.0 parts by mass, and [C] acid diffusion control agent (C-1) 2.3 mass parts Parts, (E-1) 5.0 parts by mass (solid content) as [E] polymer, and 3,230 (D-1)/(D-2)/(D-3) mixed solvent as [D] solvent The mass parts were mixed and filtered with a membrane filter with a pore size of 0.2 μm, thereby preparing a radiation-sensitive resin composition (J-1).

[Example 2 to Example 47 and Comparative Example 1 to Comparative Example 11] Except for the types and contents of each component shown in Table 7 and Table 8 below, the same method as in Example 1 was used to prepare radiation-sensitive resin composition (J-2) to radiation-sensitive resin composition ( J-47) and radiation-sensitive resin composition (CJ-1) ~ radiation-sensitive resin composition (CJ-11).

[Table 7] Radiation-sensitive resin composition [A] Polymer [B] Acid generator [C] Acid diffusion control agent [E] Polymer [D] Solvent species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) Example 1 J-1 A-1 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 2 J-2 A-2 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 3 J-3 A-3 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 4 J-4 A-4 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 5 J-5 A-5 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 6 J-6 A-6 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 7 J-7 A-7 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 8 J-8 A-8 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 9 J-9 A-9 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 10 J-10 A-10 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 11 J-11 A-11 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 12 J-12 A-12 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 13 J-13 A-13 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 14 J-14 A-14 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 15 J-15 A-15 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 16 J-16 A-16 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 17 J-17 A-17 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 18 J-18 A-18 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 19 J-19 A-19 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 20 J-20 A-20 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 21 J-21 A-21 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 22 J-22 A-22 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 23 J-23 A-23 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 24 J-24 A-24 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 25 J-25 A-25 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 26 J-26 A-26 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 27 J-27 A-27 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 28 J-28 A-28 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 29 J-29 A-29 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 30 J-30 A-30 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 31 J-31 A-31 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 32 J-32 A-32 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 33 J-33 A-33 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 34 J-34 A-34 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 35 J-35 A-35 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 36 J-36 A-36 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 37 J-37 A-37 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30

[Table 8] Radiation-sensitive resin composition [A] Polymer [B] Acid generator [C] Acid diffusion control agent [E] Polymer [D] Solvent species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) Example 38 J-38 A-1 100 B-1 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 39 J-39 A-1 100 B-2 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 40 J-40 A-1 100 B-3 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 41 J-41 A-1 100 B-5 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 42 J-42 A-1 100 B-4 14.0 C-2 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 43 J-43 A-1 100 B-4 14.0 C-3 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 44 J-44 A-1 100 B-4 14.0 C-4 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 45 J-45 A-1 100 B-4 14.0 C-5 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Example 46 J-46 A-1 100 B-4 14.0 C-1 2.3 E-2 5.0 D-1/D-2/D-3 2240/960/30 Example 47 J-47 A-1 100 B-4 14.0 C-1 2.3 E-3 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 1 CJ-1 A-38 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 2 CJ-2 A-39 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 3 CJ-3 A-40 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 4 CJ-4 A-41 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 5 CJ-5 A-42 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 6 CJ-6 A-43 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 7 CJ-7 A-44 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 8 CJ-8 A-45 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 9 CJ-9 A-46 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 10 CJ-10 A-47 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30 Comparative example 11 CJ-11 A-48 100 B-4 14.0 C-1 2.3 E-1 5.0 D-1/D-2/D-3 2240/960/30

<Formation of resist pattern using positive radiation-sensitive resin composition for ArF exposure> Using a spin coater ("CLEAN TRACK ACT12" of Tokyo Electron Co., Ltd.), the composition for forming the lower anti-reflection film ("ARC66" of Brewer Science) was applied to 12 After the silicon wafer is placed on the silicon wafer, it is heated at 205°C for 60 seconds to form a lower anti-reflection film with an average thickness of 105 nm. On the lower anti-reflective film, the positive radiation-sensitive resin composition for ArF exposure prepared above was coated using the spin coater, and PB (pre-baking) was performed at 90° C. for 60 seconds. Thereafter, it was cooled at 23° C. for 30 seconds, thereby forming a resist film with an average thickness of 90 nm. Secondly, for the resist film, an ArF excimer laser immersion exposure device ("TWINSCAN XT-1900i" from ASML) was used to set the numerical aperture (NA) = 1.35 and ring ( Annular) (σ=0.8/0.6) under the optical conditions, the mask pattern is exposed with a space of 40 nm and a pitch of 105 nm. After exposure, PEB (post-exposure bake) was performed at 90°C for 60 seconds. Thereafter, the resist film was alkali-developed using a 2.38% by mass TMAH aqueous solution as an alkaline developer, washed with water after the development, and then dried to form a positive resist pattern ( 40 nm line and space pattern). In addition, the mask pattern was changed, and other than that, a positive resist pattern (40 nm hole, 105 nm pitch) was formed in the same manner as the operation described above.

＜Evaluation＞ Regarding the resist pattern formed using the radiation-sensitive resin composition for ArF exposure, the sensitivity, CDU performance, and LWR performance were evaluated in accordance with the following methods. The results are shown in Table 9 below. Furthermore, for the length measurement of the resist pattern, a scanning electron microscope (“CG-5000” of Hitachi High-Technologies (stock)) is used.

[Sensitivity] In the formation of the resist pattern using the radiation-sensitive resin composition for ArF exposure, the exposure level for forming the 40 nm line and space pattern was taken as the optimal exposure level, and the optimal exposure level was taken as the sensitivity (MJ/cm ² ). Regarding the sensitivity, when it is 25 mJ/cm ² or less, it is evaluated as "good", and when it exceeds 25 mJ/cm ² it is evaluated as "poor".

[CDU performance] Using the scanning electron microscope, the length of the resist pattern with a total of 1,800 40 nm holes and 105 nm pitch was measured from the upper part of the pattern at any point. Calculate the size deviation (3σ) and use it as the CDU performance (nm). The smaller the value of CDU, the smaller and better the deviation of the pore diameter in the long period. Regarding the CDU performance, it was evaluated as "good" when it was 4.0 nm or less, and it was evaluated as "bad" when it was over 4.0 nm.

[LWR performance] The optimum exposure amount obtained in the evaluation of the sensitivity is irradiated, and the mask size is adjusted to form a 40 nm line and space pattern to form a resist pattern. Using the scanning electron microscope, the formed resist pattern was observed from the upper part of the pattern. The deviation of the line width at 500 points in total was measured, the 3 sigma value was obtained from the distribution of the measured values, and the 3 sigma value was taken as LWR (nm). The smaller the value of LWR, the smaller and better the roughness of the line. Regarding the LWR performance, when it is 3.5 nm or less, it is evaluated as "good", and when it exceeds 3.5 nm, it is evaluated as "poor".

[Table 9] Radiation-sensitive resin composition Sensitivity (mJ/cm ² ) CDU (nm) LWR (nm) Example 1 J-1 twenty two 3.6 3.1 Example 2 J-2 twenty one 3.7 2.9 Example 3 J-3 twenty three 3.5 3.1 Example 4 J-4 twenty three 3.8 3.0 Example 5 J-5 twenty three 3.7 3.0 Example 6 J-6 twenty four 3.8 3.2 Example 7 J-7 twenty four 3.8 3.3 Example 8 J-8 twenty four 3.5 3.2 Example 9 J-9 twenty two 3.7 3.3 Example 10 J-10 twenty four 3.1 3.0 Example 11 J-11 twenty three 3.7 3.2 Example 12 J-12 twenty four 3.8 3.0 Example 13 J-13 twenty three 3.6 3.3 Example 14 J-14 twenty three 3.7 3.3 Example 15 J-15 twenty four 3.6 3.2 Example 16 J-16 twenty four 3.6 3.2 Example 17 J-17 twenty three 3.7 3.3 Example 18 J-18 twenty three 3.7 2.9 Example 19 J-19 twenty three 3.8 3.0 Example 20 J-20 twenty four 3.8 3.1 Example 21 J-21 twenty four 3.7 3.0 Example 22 J-22 twenty four 3.8 2.9 Example 23 J-23 twenty two 3.6 2.8 Example 24 J-24 twenty two 3.7 3.3 Example 25 J-25 twenty four 3.8 3.2 Example 26 J-26 twenty four 3.8 3.0 Example 27 J-27 twenty four 3.7 3.1 Example 28 J-28 twenty two 3.7 3.0 Example 29 J-29 twenty two 3.7 3.2 Example 30 J-30 twenty three 3.7 3.2 Example 31 J-31 25 3.7 2.9 Example 32 J-32 25 3.8 3.1 Example 33 J-33 twenty four 3.8 3.4 Example 34 J-34 twenty three 3.7 3.1 Example 35 J-35 twenty two 3.7 3.4 Example 36 J-36 twenty three 3.7 3.3 Example 37 J-37 twenty three 3.8 3.2 Example 38 J-38 twenty two 3.6 3.3 Example 39 J-39 twenty three 3.7 3.1 Example 40 J-40 twenty two 3.6 2.8 Example 41 J-41 twenty two 3.7 3.1 Example 42 J-42 twenty two 3.6 3.1 Example 43 J-43 20 3.7 3.0 Example 44 J-44 twenty one 3.6 3.2 Example 45 J-45 twenty two 3.6 3.3 Example 46 J-46 twenty two 3.6 3.1 Example 47 J-47 twenty two 3.6 3.2 Comparative example 1 CJ-1 29 4.3 4.9 Comparative example 2 CJ-2 27 4.4 4.2 Comparative example 3 CJ-3 29 4.5 4.5 Comparative example 4 CJ-4 26 4.3 3.9 Comparative example 5 CJ-5 29 4.7 4.1 Comparative example 6 CJ-6 27 4.3 3.9 Comparative example 7 CJ-7 28 4.8 4.6 Comparative example 8 CJ-8 29 4.3 4.9 Comparative example 9 CJ-9 26 4.1 3.7 Comparative example 10 CJ-10 26 4.2 3.8 Comparative example 11 CJ-11 26 4.1 3.6

As is clear from the results in Table 9, when the radiation-sensitive resin composition of the example is used for ArF exposure, the sensitivity, CDU performance, and LWR performance are good. In contrast, in the comparative example, the characteristics and implementation Cases are worse. Therefore, when the radiation-sensitive resin composition of the example is used for ArF exposure, a resist pattern with good CDU performance and LWR performance can be formed with high sensitivity.

[Preparation of radiation-sensitive resin composition for extreme ultraviolet (EUV) exposure] [Example 48] [A] polymer (A-48) 100 parts by mass, [B] acid generator (B-4) 14.0 parts by mass, and [C] acid diffusion control agent (C-1) 2.3 mass parts Parts, 5.0 parts by mass of [E] polymer (E-4), and 6,110 parts by mass of a mixed solvent of (D-1)/(D-4) as [D] solvent, using a membrane with a pore size of 0.2 μm The filter is filtered to prepare a radiation-sensitive resin composition (J-48).

[Example 49 to Example 60 and Comparative Example 12 to Comparative Example 14] Using the types and contents of the components shown in Table 10 below, except for this, the radiation-sensitive resin composition (J-49) to the radiation-sensitive resin composition (J-60) were prepared in the same manner as in Example 48 ) And radiation-sensitive resin composition (CJ-12) ~ radiation-sensitive resin composition (CJ-14).

[Table 10] Radiation-sensitive resin composition [A] Polymer [B] Acid generator [C] Acid diffusion control agent [E] Polymer [D] Solvent species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) species Content (parts by mass) Example 48 J-48 A-49 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 49 J-49 A-50 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 50 J-50 A-51 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 51 J-51 A-52 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 52 J-52 A-53 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 53 J-53 A-49 100 B-1 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 54 J-54 A-49 100 B-2 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 55 J-55 A-49 100 B-3 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 56 J-56 A-49 100 B-5 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 57 J-57 A-49 100 B-4 14.0 C-2 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 58 J-58 A-49 100 B-4 14.0 C-3 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 59 J-59 A-49 100 B-4 14.0 C-4 2.3 E-4 5.0 D-1/D-4 4280/1830 Example 60 J-60 A-49 100 B-4 14.0 C-5 2.3 E-4 5.0 D-1/D-4 4280/1830 Comparative example 12 CJ-12 A-54 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Comparative example 13 CJ-13 A-55 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830 Comparative example 14 CJ-14 A-56 100 B-4 14.0 C-1 2.3 E-4 5.0 D-1/D-4 4280/1830

<Formation of resist pattern using radiation-sensitive resin composition for EUV exposure> Using a spin coater ("CLEAN TRACK ACT12" of Tokyo Electron Co., Ltd.), the composition for forming the lower anti-reflection film ("ARC66" of Brewer Science) was applied to 12 After the silicon wafer is placed on the silicon wafer, it is heated at 205°C for 60 seconds to form a lower anti-reflection film with an average thickness of 105 nm. On the lower anti-reflection film, the above-prepared radiation-sensitive resin composition for EUV exposure was coated using the spin coater, and PB was performed at 130°C for 60 seconds. Thereafter, it was cooled at 23°C for 30 seconds, thereby forming a resist film with an average thickness of 55 nm. Next, the resist film was exposed using an EUV exposure device (ASML "NXE3300") with NA=0.33, lighting conditions: Conventional s=0.89, and mask: imecDEFECT32FFR02. After exposure, PEB was performed at 120°C for 60 seconds. Thereafter, the resist film was alkali-developed using a 2.38% by mass TMAH aqueous solution as an alkaline developer, washed with water after the development, and then dried to form a positive resist pattern ( 32 nm line and space pattern).

＜Evaluation＞ Regarding the resist pattern formed using the radiation-sensitive resin composition for EUV exposure, the sensitivity and LWR performance were evaluated in accordance with the following methods. The results are shown in Table 11 below. Furthermore, for the length measurement of the resist pattern, a scanning electron microscope (“CG-5000” of Hitachi High-Technologies (stock)) is used.

[Sensitivity] In the formation of the resist pattern using the radiation-sensitive resin composition for EUV exposure, the exposure level for forming the 32 nm line and space pattern is taken as the optimal exposure level, and the optimal exposure level is taken as the sensitivity (MJ/cm ² ). Regarding the sensitivity, when it was 30 mJ/cm ² or less, it was evaluated as "good", and when it exceeded 30 mJ/cm ² it was evaluated as "poor".

[LWR performance] The optimum exposure amount obtained in the evaluation of the sensitivity is irradiated, and the mask size is adjusted to form a 32 nm line and space pattern to form a resist pattern. Using the scanning electron microscope, the formed resist pattern was observed from the upper part of the pattern. The deviation of the line width at 500 points in total was measured, and the 3 sigma value was obtained from the distribution of the measured values, and the 3 sigma value was taken as LWR (nm). The smaller the value of LWR, the smaller and better the line wobble. Regarding the LWR performance, when it is 3.5 nm or less, it is evaluated as "good", and when it exceeds 3.5 nm, it is evaluated as "poor".

[Table 11] Radiation-sensitive resin composition Sensitivity (mJ/cm ² ) LWR (nm) Example 48 J-48 28 3.3 Example 49 J-49 27 3.2 Example 50 J-50 28 3.2 Example 51 J-51 28 3.3 Example 52 J-52 29 3.2 Example 53 J-53 27 3.1 Example 54 J-54 27 3.2 Example 55 J-55 28 3.2 Example 56 J-56 28 3.2 Example 57 J-57 28 3.2 Example 58 J-58 27 3.3 Example 59 J-59 28 3.3 Example 60 J-60 29 3.3 Comparative example 12 CJ-12 34 3.9 Comparative example 13 CJ-13 36 4.0 Comparative example 14 CJ-14 34 4.0

As is clear from the results of Table 11, when the radiation-sensitive resin composition of the examples is used for EUV exposure, the sensitivity and LWR performance are good. In contrast, in the comparative examples, the characteristics are compared with those of the examples. difference.

[Preparation of negative radiation-sensitive resin composition for ArF exposure, formation and evaluation of resist pattern using the composition] [Example 61] [A] polymer (A-1) 100 parts by mass, [B] acid generator (B-4) 14.0 parts by mass, and [C] acid diffusion control agent (C-1) 2.3 mass parts Parts, 2.0 parts by mass (solid content) of (E-3) as [E] polymer, and 3,230 of mixed solvents of (D-1)/(D-2)/(D-3) as [D] solvent The mass parts were mixed and filtered with a membrane filter with a pore size of 0.2 μm, thereby preparing a radiation-sensitive resin composition (J-61).

Using a spin coater ("CLEAN TRACK ACT12" of Tokyo Electron Co., Ltd.), the composition for forming the lower anti-reflection film ("ARC66" of Brewer Science) was applied to 12 After the silicon wafer is placed on the silicon wafer, it is heated at 205°C for 60 seconds to form a lower anti-reflection film with an average thickness of 105 nm. On the lower anti-reflective film, the negative radiation-sensitive resin composition (J-61) for ArF exposure prepared above was coated with the spin coater, and pre-baked at 90°C for 60 seconds ( PB). Thereafter, it was cooled at 23° C. for 30 seconds, thereby forming a resist film with an average thickness of 90 nm. Secondly, for the resist film, an ArF excimer laser immersion exposure device ("TWINSCAN XT-1900i" from ASML) was used, with NA=1.35, Annular (σ=0.8/ Under the optical condition of 0.6), the mask pattern is exposed with a space of 40 nm and a pitch of 105 nm. After exposure, PEB (post-exposure bake) was performed at 90°C for 60 seconds. Thereafter, using n-butyl acetate as an organic solvent developer, the resist film was developed with an organic solvent and dried, thereby forming a negative resist pattern (40 nm line and space pattern).

The resist pattern using the negative radiation sensitive resin composition for ArF exposure was evaluated in the same manner as the evaluation of the resist pattern using the positive radiation sensitive resin composition for ArF exposure. As a result, the radiation-sensitive resin composition of Example 61 has good sensitivity, CDU performance, and LWR performance even when a negative resist pattern is formed by ArF exposure. [Industrial availability]

According to the radiation-sensitive resin composition and the resist pattern forming method of the present invention, it is possible to form a resist pattern with good sensitivity to exposure light and excellent LWR performance and CDU performance. The polymer of the present invention can be preferably used as the polymer component of the radiation-sensitive resin composition. The compound of the present invention can be preferably used as a monomer of the polymer. Therefore, these can be preferably used in the processing of semiconductor devices that are expected to be further miniaturized in the future.

no

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Claims (11)

A radiation-sensitive resin composition comprising: a polymer having a structural unit represented by the following formula (1); and a radiation-sensitive acid generator,

In the formula (1), A is an oxygen atom or a sulfur atom; m+n is 2 or 3, m is 1 or 2, n is 1 or 2; X is a divalent organic group with 1 to 20 carbons; R ¹ is an acid dissociable group or a polar group. The radiation-sensitive resin composition according to claim 1, wherein the ^{acid dissociable group of R 1} in the formula (1) is a group represented by the following formula (1-1) or formula (1-2),

In the formula (1-1), R ^1A is a monovalent hydrocarbon group having 1 to 20 carbons; R ^1B and R ^1C are each independently a monovalent organic group having 1 to 20 carbons, or represent R ^1B and R ^1C A part of a ring structure with 3 to 20 ring members that is bonded to each other and constituted together with the carbon atoms to which it is bonded; * represents the position bonded to the oxygen atom ^{adjacent to R 1 of the formula (1);} In the formula (1-2), Y is -O- or -S-; R ^1D and R ^1E are each independently a monovalent hydrocarbon group having 1 to 20 carbons, or that R ^1D and R ^1E are combined with each other and These bonded atomic chains together constitute a part of a ring structure with 4 to 20 ring members; * represents the bonding site to the oxygen atom ^{adjacent to R 1 of the formula (1).} The radiation-sensitive resin composition according to claim 1 or claim 2, wherein the ^{polar group of R 1} in the formula (1) is the following (2-1), (2-2) or (2-3) _{The group represented by (2-1) has -O-, -CO-, -SO 2} -or -NH- between the carbon-carbon bonds constituting the substituted or unsubstituted hydrocarbon group having 2 to 20 carbons The monovalent organic group (excluding those contained in (2-3) below); (2-2) One or more hydrogen atoms that constitute a substituted or unsubstituted hydrocarbon group with 1 to 20 carbon atoms A monovalent organic group of a structure substituted with a halogen atom, -OH, -COOH, -CN or -NH ₂ (excluding those contained in the following (2-3)); (2-3) When the carbon number is 2 ～20 substituted or unsubstituted hydrocarbon groups have -O-, _{-CO-, -SO 2} -or -NH- between the carbon-carbon bonds, and have one or more hydrogen atoms constituting the hydrocarbon group via halogen atoms , -OH, -COOH, -CN or -NH ₂ substituted structure monovalent organic group. The radiation-sensitive resin composition according to claim 2 or claim 3, wherein X in the formula (1) is a divalent hydrocarbon group having 1 to 20 carbons, -X ¹ -O- ^{, -X 2} -NH- Or -X ³ -OX ⁴ -, wherein the X ¹ , the X ² , the X ³ and the X ⁴ are each independently a divalent hydrocarbon group having 1 to 20 carbons. The radiation-sensitive resin composition according to claim 4, wherein the divalent hydrocarbon groups having 1 to 20 carbons ^{of X, X 1} , X ² , X ³ and X ^{4 in the formula (1) are each independently carbon} A divalent chain hydrocarbon group having 1 to 4, a divalent alicyclic hydrocarbon group having 6 to 10 carbons, or a divalent aromatic hydrocarbon group having 6 to 10 carbons. A method for forming a resist pattern includes: a coating step of directly or indirectly applying a radiation-sensitive resin composition to a substrate; a step of exposing the resist film formed by the coating step; And a step of developing the exposed resist film, and the radiation-sensitive resin composition contains: a polymer having a structural unit represented by the following formula (1); and a radiation-sensitive acid generator ,

In the formula (1), A is an oxygen atom or a sulfur atom; m+n is 2 or 3, m is 1 or 2, n is 1 or 2; X is a divalent organic group with 1 to 20 carbons; R ¹ is an acid dissociable group or a polar group. The method for forming a resist pattern according to claim 6, wherein the ^{acid dissociable group of R 1} of the formula (1) is a group represented by the following formula (1-1) or formula (1-2),

In the formula (1-1), R ^1A is a monovalent hydrocarbon group having 1 to 20 carbons; R ^1B and R ^1C are each independently a monovalent organic group having 1 to 20 carbons, or represent R ^1B and R ^1C A part of a ring structure with 3 to 20 ring members that is bonded to each other and constituted together with the carbon atoms to which it is bonded; * represents the position bonded to the oxygen atom ^{adjacent to R 1 of the formula (1);} In the formula (1-2), Y is -O- or -S-; R ^1D and R ^1E are each independently a monovalent hydrocarbon group having 1 to 20 carbons, or that R ^1D and R ^1E are combined with each other and These bonded atomic chains together constitute a part of a ring structure with 4 to 20 ring members; * represents the bonding site to the oxygen atom ^{adjacent to R 1 of the formula (1).} A polymer having a structural unit represented by the following formula (1),

In the formula (1), A is an oxygen atom or a sulfur atom; m+n is 2 or 3, m is 1 or 2, n is 1 or 2; X is a divalent organic group with 1 to 20 carbons; R ¹ is an acid dissociable group or a polar group. The polymer according to claim 8, wherein the ^{acid dissociable group of R 1} in the formula (1) is a group represented by the following formula (1-1) or formula (1-2),

In the formula (1-1), R ^1A is a monovalent hydrocarbon group having 1 to 20 carbons; R ^1B and R ^1C are each independently a monovalent organic group having 1 to 20 carbons, or represent R ^1B and R ^1C A part of a ring structure with 3 to 20 ring members that is bonded to each other and constituted together with the carbon atoms to which it is bonded; * represents the position bonded to the oxygen atom ^{adjacent to R 1 of the formula (1);} In the formula (1-2), Y is -O- or -S-; R ^1D and R ^1E are each independently a monovalent hydrocarbon group having 1 to 20 carbons, or that R ^1D and R ^1E are combined with each other and These bonded atomic chains together constitute a part of a ring structure with 4 to 20 ring members; * represents the bonding site to the oxygen atom ^{adjacent to R 1 of the formula (1).} A compound represented by the following formula (i):

In the formula (i), A is an oxygen atom or a sulfur atom; m+n is 2 or 3, m is 1 or 2, n is 1 or 2; X is a divalent organic group with 1 to 20 carbons; R ¹ is an acid dissociable group or a polar group. The compound according to claim 10, wherein the ^{acid dissociable group of R 1} of the formula (i) is a group represented by the following formula (1-1) or formula (1-2),

In the formula (1-1), R ^1A is a monovalent hydrocarbon group having 1 to 20 carbons; R ^1B and R ^1C are each independently a monovalent organic group having 1 to 20 carbons, or represent R ^1B and R ^1C A part of a ring structure with 3 to 20 ring members that is bonded to each other and constituted together with the carbon atoms to which it is bonded; * represents the position bonded to the oxygen atom ^{adjacent to R 1 of the formula (i);} In the formula (1-2), Y is -O- or -S-; R ^1D and R ^1E are each independently a monovalent hydrocarbon group having 1 to 20 carbons, or that R ^1D and R ^1E are combined with each other and These bonded atomic chains together constitute a part of a ring structure with 4 to 20 ring members; * represents the bonding site to the oxygen atom ^{adjacent to R 1 of the formula (i).}