WO2016159187A1

WO2016159187A1 - Radiation-sensitive composition and pattern forming method

Info

Publication number: WO2016159187A1
Application number: PCT/JP2016/060569
Authority: WO
Inventors: 恭志中川; 宗大白谷; 岳彦成岡; 永井　智樹
Original assignee: Jsr株式会社
Priority date: 2015-04-01
Filing date: 2016-03-30
Publication date: 2016-10-06
Also published as: TW201642030A

Abstract

The radiation-sensitive composition according to the present invention contains a polymer having a first structural unit containing an acid-dissociable group, a radiation-sensitive acid generator, and a metal-containing component, wherein the contained amount of the metal-containing component is 0.1 parts by mass or more with respect to 100 parts by mass of the polymer, and an absorbance derived from the metal-containing component in a solution containing only the metal-containing component in an amount of 0.0001 mass% calculated in terms of metal atoms in a measurement solvent having a transmittance of 95% or more in an entire wavelength region of 250-600 nm, is less than 0.01 in the entire wavelength region of 250-600 nm.

Description

Radiation-sensitive composition and pattern forming method

The present invention relates to a radiation-sensitive composition and a pattern forming method.

Radiation sensitive compositions used for microfabrication by lithography are exposed to irradiated parts such as deep ultraviolet rays such as ArF excimer laser light and KrF excimer laser light, electromagnetic waves such as extreme ultraviolet rays (EUV), and charged particle beams such as electron beams. An acid is generated in the substrate, and a chemical reaction using the acid as a catalyst causes a difference in the dissolution rate of the exposed portion and the unexposed portion in the developer, thereby forming a pattern on the substrate.

Such a radiation-sensitive composition is required to improve resist performance as the processing technique becomes finer. In response to this requirement, the types and molecular structures of polymers, acid generators and other components used in the composition have been studied, and further their combinations have been studied in detail (Japanese Patent Application Laid-Open No. 11-125907, special features). (See Kaihei 8-146610 and JP-A 2000-298347).

Currently, pattern miniaturization has progressed to a level of 40 nm or less, but the radiation-sensitive composition has higher resist performance, especially sensitivity to exposure light such as electron beams and EUV. Is required. In addition, it is also required to further reduce the nano edge roughness of the pattern. However, these requirements cannot be met.

JP-A-11-125907 JP-A-8-146610 JP 2000-298347 A

The present invention has been made based on the above circumstances, and an object of the present invention is to provide a radiation-sensitive composition and a pattern forming method excellent in sensitivity and nanoedge roughness performance.

The invention made in order to solve the above-mentioned problem is a polymer having a first structural unit (hereinafter also referred to as “structural unit (I)”) containing an acid dissociable group (hereinafter referred to as “[A] polymer”). A radiation-sensitive acid generator (hereinafter also referred to as “[B] acid generator”), and a metal-containing component (hereinafter also referred to as “[C] metal-containing component”). The measurement of [C] the content of the [C] metal-containing component with respect to 100 parts by mass of the polymer [A] is 0.1 parts by mass or more and the transmittance in the entire wavelength region of 250 nm to 600 nm is 95% or more. Absorbance due to the [C] metal-containing component in the solution containing only 0.001% by mass of the [C] metal-containing component in terms of metal atoms in the solvent is less than 0.01 in the entire wavelength region of 250 nm to 600 nm. A feeling characterized by Ray composition (hereinafter, "radiation-sensitive composition (I)" also referred) is.

Another invention made in order to solve the above-mentioned problems contains a [A] polymer, a [B] acid generator, and a [C] metal-containing component (hereinafter also referred to as “[C1] metal-containing component”). The content of the [C1] metal-containing component with respect to 100 parts by mass of the [A] polymer is 0.1 parts by mass or more, and the [C1] metal-containing component is represented by the following formula (1). It is a radiation sensitive composition (henceforth "radiation sensitive composition (II)") characterized by being represented by this.

(In Formula (1), M is a metal atom. ^RA is a substituted or unsubstituted alkyl group, alkoxyalkyl group, (poly) cycloalkyl group, alkoxy (poly) with a group having no aromatic ring. A cycloalkyl group, a (poly) cycloalkyloxy (poly) cycloalkyl group, or a combination of these groups and a sulfonyl group, m is an integer of 1 to 6. When m is 2 or more, R ^A may be the same or different, and a plurality of R ^A may be combined with each other to form a ring structure having 4 to 20 ring members together with the oxygen atom to which they are bonded and the metal atom to which the oxygen atom is bonded. Good.)

Still another invention made in order to solve the above-mentioned problems is that [A] a polymer, [B] an acid generator, and [C] a metal-containing component (hereinafter also referred to as “[C2] metal-containing component”). A radiation-sensitive composition to be contained, wherein the content of the [C] metal-containing component with respect to 100 parts by mass of the [A] polymer is 0.1 parts by mass or more, and the [C] metal-containing component is an alkoxy group. , (Poly) cycloalkyloxy group, alkylcarbonyloxy group, metal compound (I) having (poly) cycloalkylcarbonyloxy group or a combination thereof, hydrolyzate of metal compound (I), metal compound (I) And a metal-containing compound (hereinafter also referred to as “[X] metal-containing compound”) which is a hydrolyzed condensate of the above or a combination thereof, and at least one organic compound represented by the following formula (L-1) ( A complex obtained by mixing with “[Y] organic compound” (hereinafter also referred to as “[a] complex”) or a product obtained by hydrolytic condensation of this complex (hereinafter referred to as “[b ] A hydrolyzate ”), and a radiation-sensitive composition (hereinafter, also referred to as“ radiation-sensitive composition (III) ”).

(In the formula (L-1), R ¹ represents n from alkane, alkene, (poly) cycloalkane, (poly) cycloalkene, dialkyl ether, di (poly) cycloalkyl ether or alkyl (poly) cycloalkyl ether. X is —OH, —COOR ^a , —NCO or —NHR ^a, where R ^a is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or 3 to 20 carbon atoms. (N) is an integer of 1 to 4. When n is 2 or more, a plurality of Xs may be the same or different.

Still another invention made in order to solve the above-mentioned problems comprises a step of forming a film, a step of exposing the film, and a step of developing the exposed film, and the film is treated with the radiation-sensitive composition. (I) It is a pattern formation method formed with the said radiation sensitive composition (II) or the said radiation sensitive composition (III).

Here, the “acid-dissociable group” refers to a group that replaces a hydrogen atom such as a carboxy group, a sulfo group, or a phenolic hydroxyl group, and dissociates by the action of an acid. “Number of ring members” means the number of atoms constituting the ring of the alicyclic structure, aromatic ring structure, aliphatic heterocyclic structure and aromatic heterocyclic structure, and in the case of polycyclic, the number of atoms constituting this polycyclic ring Say. “Aromatic ring” of a group having no aromatic ring includes both aromatic carbon rings such as phenyl group, naphthyl group and anthryl group and aromatic heterocyclic rings such as pyrrole ring, furan ring, thiophene ring and pyridine ring. It is a concept. The “(poly) cycloalkyl group” is a concept including both a cycloalkyl group (monocyclic alicyclic saturated hydrocarbon group) and a polycycloalkyl group (polycyclic alicyclic saturated hydrocarbon group). The same applies to (poly) cycloalkane, (poly) cycloalkene and the like.

According to the radiation-sensitive composition and pattern formation method of the present invention, a pattern with small nanoedge roughness can be formed while exhibiting high sensitivity. Therefore, these can be suitably used for manufacturing semiconductor devices that are expected to be further miniaturized in the future.

It is a typical top view at the time of seeing a line pattern from the upper part. It is typical sectional drawing of a line pattern shape.

<Radiation sensitive composition (I)>
Radiation sensitive composition (I) contains a [A] polymer, a [B] acid generator, and a [C] metal containing component. The radiation-sensitive composition (I) may contain [D] acid diffusion controller and [E] solvent as suitable components, and contains other optional components as long as the effects of the present invention are not impaired. May be. Hereinafter, each component will be described.

<[A] polymer>
[A] The polymer is a polymer having the structural unit (I). “Polymer” refers to a compound formed by combining monomers by the formation of a covalent bond, and includes polymers and oligomers. [A] The lower limit of the molecular weight of the polymer is, for example, 500, preferably 1,000. [A] When the polymer has the structural unit (I), the acid dissociable group is dissociated by the action of an acid generated from the acid generator [B] described later. As a result, the solubility of the [A] polymer in the developer changes, so that a pattern can be formed with the radiation-sensitive composition (I).

[A] The polymer is not particularly limited as long as it has the structural unit (I). For example, the polymer having the structural unit (I) (hereinafter also referred to as “[A1] polymer”), the structural unit (I) And calixarene (hereinafter also referred to as “[A2] polymer”). The “calixarene” refers to a cyclic oligomer in which a plurality of aromatic rings to which a hydroxy group is bonded or heteroaromatic rings to which a hydroxy group is bonded are bonded cyclically through a hydrocarbon group.

[[A1] polymer]
[A1] The polymer is a polymer having the structural unit (I). [A1] In addition to the structural unit (I), the polymer includes a second structural unit represented by the formula (3) (hereinafter also referred to as “structural unit (II)”), a lactone structure, and a cyclic carbonate structure. , May have a structural unit (III) containing a sultone structure or a combination thereof, and may have other structural units other than (I) to (III). [A1] In the polymer, various structural units can be easily introduced, and the solubility in a developer can be adjusted. As a result, the resist performances of the radiation sensitive composition (I) can be further improved. [A1] The polymer may have one or more of each structural unit. Hereinafter, each structural unit will be described.

[Structural unit (I)]
The structural unit (I) is a structural unit containing an acid dissociable group. [A1] As the structural unit (I) in the polymer, for example, a structural unit represented by the following formula (2-1) or the following formula (2-2) (hereinafter represented by the following formula (2-1): And the structural unit represented by the following formula (2-2) is also referred to as “structural unit (I-2)”.

In the above formula (2-1), R ² is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R ³ is a monovalent hydrocarbon group having 1 to 20 carbon atoms. R ⁴ and R ⁵ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms, or a ring member having 3 to 5 members composed of these groups together with the carbon atom to which they are bonded. 20 alicyclic structures are represented.
In the above formula (2-2), R ⁶ is a hydrogen atom or a methyl group. L ¹ is a single bond, —COO— or —CONH—. R ⁷ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. R ⁸ and R ⁹ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms or a monovalent oxyhydrocarbon group having 1 to 20 carbon atoms.

The “hydrocarbon group” includes a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. The “hydrocarbon group” may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. The “chain hydrocarbon group” refers to a hydrocarbon group that does not include a cyclic structure but includes only a chain structure, and includes both a linear hydrocarbon group and a branched hydrocarbon group. The term “alicyclic hydrocarbon group” refers to a hydrocarbon group that includes only an alicyclic structure as a ring structure and does not include an aromatic ring structure, and includes a monocyclic alicyclic hydrocarbon group and a polycyclic alicyclic group. Includes both hydrocarbon groups. However, it is not necessary to be composed only of the alicyclic structure, and a part thereof may include a chain structure. “Aromatic hydrocarbon group” refers to a hydrocarbon group containing an aromatic ring structure as a ring structure. However, it is not necessary to be composed only of an aromatic ring structure, and a part thereof may include a chain structure or an alicyclic structure.

As the structural unit (I-1), structural units represented by the following formulas (2-1-1) to (2-1-4) (hereinafter referred to as “structural units (I-1-1) to (I-1) -4) ") is preferred. As the structural unit (I-2), a structural unit represented by the following formula (2-2-1) (hereinafter also referred to as “structural unit (I-2-1)”) is preferable.

In the above formulas (2-1-1) to (2-1-4), R ² to R ⁵ have the same meanings as the above formula (2-1). n _p is each independently an integer of 1 to 4.
In the above formula (2-2-1), R ⁶ to R ⁹ are synonymous with the above formula (2-2).

Examples of the structural unit (I-1) include a structural unit represented by the following formula.

In the above formula, R ² has the same meaning as in the above formula (2-1).

Examples of the structural unit (I-2) include a structural unit represented by the following formula.

In the above formula, R ⁶ has the same meaning as in the above formula (2-2).

As the structural unit (I-1), the structural unit (I-1-2) and the structural unit (I-1-3) are preferable, and the structural unit derived from 1-alkylcyclopentan-1-yl (meth) acrylate And structural units derived from 2-adamantyl-2-propyl (meth) acrylate are more preferred.
The structural unit (I-2) is preferably a structural unit (I-2-1), more preferably a structural unit derived from 1-oxyhydrocarbon-substituted-1-alkyloxystyrene, and 1- (poly) cycloalkyl. A structural unit derived from -1-alkyloxystyrene is more preferable, and a structural unit derived from 1-cyclohexylethyloxy-1-ethyloxystyrene is particularly preferable.

As a minimum of the content rate of structural unit (I), 10 mol% is preferable with respect to all the structural units which comprise a [A1] polymer, 20 mol% is more preferable, 30 mol% is further more preferable, 40 mol% % Is particularly preferred. As an upper limit of the said content rate, 80 mol% is preferable, 70 mol% is more preferable, 60 mol% is further more preferable, 55 mol% is especially preferable. By making the said content rate into the said range, the nano edge roughness performance of a radiation sensitive composition (I) can be improved more.

[Structural unit (II)]
The structural unit (II) is a structural unit containing a phenolic hydroxyl group. [A1] The polymer further has the structural unit (II), so that the solubility in the developer can be adjusted more appropriately. As a result, the nano-edge roughness performance of the radiation-sensitive composition (I) is further improved. Can be improved. In addition, the adhesion of the pattern to the substrate can be improved. Furthermore, in the case of KrF exposure, EUV exposure or electron beam exposure, the sensitivity of the radiation-sensitive composition (I) can be further increased.

Examples of the structural unit (II) include a structural unit represented by the following formula (3) (hereinafter also referred to as “structural unit (II-1)”).

In the formula ^{(3), R 15} is a hydrogen atom or a methyl group. L ² is a single bond or a divalent organic group having 1 to 20 carbon atoms. R ¹⁶ is a monovalent organic group having 1 to 20 carbon atoms. p is an integer of 0-2. q is an integer of 0 to 9. When q is 2 or more, the plurality of R ¹⁶ may be the same or different. r is an integer of 1 to 3.

Examples of the structural unit (II) include structural units represented by the following formulas (3-1) to (3-7) (hereinafter also referred to as “structural units (II-1) to (II-7)”), etc. Is mentioned.

In the above formulas (3-1) to (3-7), R ¹⁵ has the same meaning as in the above formula (3).

Of these, the structural unit (II-1) is preferred.

[A1] When the polymer has the structural unit (II), the content ratio of the structural unit (II) is preferably 10 mol%, preferably 30 mol% with respect to all the structural units constituting the [A1] polymer. Is more preferable, and 45 mol% is more preferable. As an upper limit of the said content rate, 80 mol% is preferable, 70 mol% is more preferable, and 60 mol% is further more preferable. By making the content rate of structural unit (II) into the said range, the nano edge roughness performance of a radiation sensitive composition (I) can further be improved. In addition, the sensitivity in the case of KrF exposure, EUV exposure, or electron beam exposure can be further increased.

[Structural unit (III)]
The structural unit (III) is a structural unit including a lactone structure, a cyclic carbonate structure, a sultone structure, or a combination thereof. [A1] The polymer further has the structural unit (III), so that the solubility in the developer can be further adjusted. As a result, the nanoedge roughness performance of the radiation-sensitive composition (I) is further improved. Can be improved. Further, the adhesion between the pattern and the substrate can be further improved.

Examples of the structural unit (III) include a structural unit represented by the following formula.

In the above formula, R ^L1 represents a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group.

Among these, the structural unit (III) is preferably a structural unit containing a lactone structure, more preferably a structural unit containing a norbornane lactone structure or a structural unit derived from cyanonorbornane lactone-yl (meth) acrylate.

[A1] When the polymer has the structural unit (III), the lower limit of the content ratio of the structural unit (III) is preferably 10 mol% with respect to all the structural units constituting the polymer. Mole% is more preferable, and 40 mol% is more preferable. As an upper limit of the said content rate, 70 mol% is preferable, 60 mol% is more preferable, and 55 mol% is further more preferable. By making the said content rate into the said range, the nano edge roughness performance of a radiation sensitive composition (I) can further be improved. Further, the adhesion of the pattern to the substrate can be further improved.

[Other structural units]
[A1] The polymer may have other structural units in addition to the structural units (I) to (III). Examples of other structural units include a structural unit containing a polar group and a structural unit containing a non-dissociable hydrocarbon group. Examples of the polar group include an alcoholic hydroxyl group, a carboxy group, a cyano group, a nitro group, and a sulfonamide group. Examples of the non-dissociable hydrocarbon group include a linear alkyl group. As an upper limit of the content rate of another structural unit, 20 mol% is preferable and 10 mol% is more preferable.

[A1] The lower limit of polystyrene-equivalent weight average molecular weight (Mw) by gel permeation chromatography (GPC) of the polymer is preferably 1,500, more preferably 2,000, still more preferably 4,000, 000 is particularly preferred. The upper limit of Mw is preferably 50,000, more preferably 30,000, still more preferably 20,000, and particularly preferably 10,000. [A] By making Mw of a polymer into the said range, the sensitivity and limit resolution of a radiation sensitive composition (I) can be improved more.

[A1] The upper limit of the ratio (Mw / Mn) of Mw to the number average molecular weight (Mn) in terms of polystyrene by GPC of the polymer is preferably 5, more preferably 3, and even more preferably 2. The lower limit of the ratio is usually 1, and 1.1 is preferable.

Mw and Mn of the polymer in this specification are values measured using gel permeation chromatography (GPC) under the following conditions.
GPC column: 2 "G2000HXL" from Tosoh Corporation, 1 "G3000HXL", 1 "G4000HXL" Column temperature: 40 ° C
Elution solvent: Tetrahydrofuran (Wako Pure Chemical Industries)
Flow rate: 1.0 mL / min Sample concentration: 1.0% by mass
Sample injection volume: 100 μL
Detector: Differential refractometer Standard material: Monodisperse polystyrene

[[A2] polymer]
[A2] The polymer is a calixarene having the structural unit (I). Radiation sensitive composition (I) can improve nano edge roughness performance more by containing [A2] polymer. [A2] Examples of the structural unit (I) in the polymer include a structural unit represented by the following formula (2-3) (hereinafter also referred to as “structural unit (I-3)”). [A2] The polymer has a structure in which the structural unit (I) is linked by a chain hydrocarbon group.

In the above formula (2-3), R ¹⁰ is a monovalent hydrocarbon group having 1 to 20 carbon atoms or a monovalent oxyhydrocarbon group having 1 to 20 carbon atoms. R ¹¹ is a single bond or a divalent hydrocarbon group having 1 to 10 carbon atoms. R ¹² is a monovalent hydrocarbon group having 1 to 20 carbon atoms. R ¹³ and R ¹⁴ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms, or a ring member having 3 to 3 members together with the carbon atoms to which these groups are combined with each other. 20 alicyclic structures are represented. a is an integer of 0-6. b is an integer of 0-6. However, a + b is 5 or less. k is 0 or 1. When a is 2 or more, the plurality of R ¹⁰ may be the same or different.

Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms and the monovalent oxyhydrocarbon group having 1 to 20 carbon atoms represented by R ¹⁰ include R ^{1 in} the formula (1) of the [C] compound described later. And a group similar to the monovalent hydrocarbon group exemplified as the above, a group containing an oxygen atom at the end of the bond side of this group, and the like.

R ¹⁰ is preferably an oxyhydrocarbon group, more preferably an alkoxy group, and still more preferably a methoxy group.

Examples of the divalent hydrocarbon group having 1 to 10 carbon atoms represented by R ¹¹ include one hydrogen atom from the groups exemplified as the monovalent hydrocarbon group having 1 to 20 carbon atoms represented by R ^10. Among the groups excluding, those having 1 to 10 carbon atoms are exemplified.

R ¹¹ is preferably a single bond or an alkanediyl group, more preferably a methanediyl group.

Examples of each group represented by R ¹² , R ¹³ and R ¹⁴ include the same groups as those exemplified as R ³ , R ⁴ and R ^{5 in} the above formula (2-1).

A is preferably an integer of 0 to 2, and more preferably 1. b is preferably an integer of 0 to 2, and more preferably 1.

[A2] The polymer may have other structural units in addition to the structural unit (I). Examples of other structural units include structural units containing a phenolic hydroxyl group.

[A2] The lower limit of the molecular weight of the polymer is preferably 500, more preferably 1,000, and even more preferably 1,500. The upper limit of the molecular weight is preferably 3,000, more preferably 2,000, and even more preferably 1,500. [A2] By setting the molecular weight of the polymer within the above range, the sensitivity and nanoedge roughness performance of the radiation-sensitive composition (I) can be further improved.

[A] The lower limit of the content of the polymer is preferably 70% by mass, more preferably 80% by mass, and still more preferably 85% by mass with respect to the total solid content of the radiation-sensitive composition (I).

<[A] Polymer Synthesis Method>
[A1] The polymer can be synthesized, for example, by polymerizing a monomer giving each structural unit in a suitable solvent using a radical polymerization initiator or the like.

Examples of radical polymerization initiators include azobisisobutyronitrile (AIBN), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (2-cyclopropylpropio). Nitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), azo radical initiators such as

dimethyl

2,2′-azobisisobutyrate; benzoyl peroxide, t-butyl hydroperoxide, cumene And peroxide radical initiators such as hydroperoxide. Of these, AIBN and dimethyl 2,2'-azobisisobutyrate are preferred, and AIBN is more preferred. These radical initiators can be used alone or in combination of two or more.

Examples of the solvent used for the polymerization include alkanes such as n-pentane, n-hexane, n-heptane, n-octane, n-nonane, and n-decane;
Cycloalkanes such as cyclohexane, cycloheptane, cyclooctane, decalin, norbornane;
Aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene;
Halogenated hydrocarbons such as chlorobutanes, bromohexanes, dichloroethanes, hexamethylene dibromide, chlorobenzene;
Saturated carboxylic acid esters such as ethyl acetate, n-butyl acetate, i-butyl acetate and methyl propionate;
Ketones such as acetone, methyl ethyl ketone, 4-methyl-2-pentanone, 2-heptanone;
Ethers such as tetrahydrofuran, dimethoxyethanes, diethoxyethanes;
Examples thereof include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, and 4-methyl-2-pentanol. The solvent used for these polymerizations may be used alone or in combination of two or more.

The lower limit of the reaction temperature in the polymerization is preferably 40 ° C, more preferably 50 ° C. As an upper limit of the said reaction temperature, 150 degreeC is preferable and 120 degreeC is more preferable. As a minimum of reaction time in a polymer, 1 hour is preferred and 2 hours is more preferred. The upper limit of the reaction time is preferably 48 hours, more preferably 24 hours.

[A2] The polymer is, for example, a compound having a phenolic hydroxyl group represented by the following formula (a) and an aldehyde represented by the following formula (b) in the presence of an acid such as trifluoroacetic acid, chloroform or the like. A compound which gives an acid-dissociable group such as 2-bromoacetyloxy-2-methyladamantane in a solvent such as N-methylpyrrolidone in the presence of a base such as potassium carbonate. It can synthesize | combine by making it react.

In the above formula (a), R ^{10 ′} is a hydrocarbon group having 1 to 20 carbon atoms. a ′ is an integer of 0 to 7. b ′ is an integer of 1 to 7. However, a ′ + b ′ is 8 or less. k is 0 or 1. When a ′ is 2 or more, a plurality of R ^{10 ′} may be the same or different.
In the above formula (b), Y represents a substituted or unsubstituted j-valent hydrocarbon group having 1 to 30 carbon atoms or a hydrogen atom. j is 1 or 2.

J is preferably 2. Y is preferably an unsubstituted divalent hydrocarbon group, more preferably an alkanediyl group, and still more preferably a propanediyl group.

<[B] Acid generator>
[B] The acid generator is a substance that generates an acid upon exposure. [B] The acid generator can be decomposed by directly absorbing the exposure light to generate an acid, and the [C] metal-containing component described later absorbs the exposure light. Acid can also be generated by decomposition by action. The generated acid dissociates the acid dissociable group or the like of the structural unit (I) of the polymer [A] to produce a carboxy group, a phenolic hydroxyl group, and the like, and the solubility of the polymer [A] in the developer is increased. Since it changes, a pattern can be formed from the radiation-sensitive composition (I). The contained form of the [B] acid generator in the radiation sensitive composition (I) may be a low molecular compound form (hereinafter also referred to as “[B] acid generator” as appropriate), as described later. It may be a form incorporated as part or both of these forms.

[B] Examples of the acid generator include onium salt compounds, N-sulfonyloxyimide compounds, halogen-containing compounds, diazoketone compounds, and the like.

Examples of the onium salt compounds include sulfonium salts, tetrahydrothiophenium salts, iodonium salts, phosphonium salts, diazonium salts, pyridinium salts, and the like.

Specific examples of the [B] acid generator include compounds described in paragraphs [0080] to [0113] of JP2009-134088A.

Examples of the sulfonium salt include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, triphenylsulfonium 2-bicyclo [2.2.1] hept- 2-yl-1,1,2,2-tetrafluoroethanesulfonate, triphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1-difluoroethanesulfonate, triphenylsulfonium camphorsulfonate, 4 -Cyclohexylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexyl Ruphenyldiphenylsulfonium perfluoro-n-octanesulfonate, 4-cyclohexylphenyldiphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-cyclohexyl Phenyldiphenylsulfonium camphorsulfonate, 4-methanesulfonylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium perfluoro-n-octanesulfonate, 4-methane Sulfonylphenyldiphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetraph Oro ethanesulfonate, 4-methanesulfonyl-phenyl camphorsulfonate,

triphenylsulfonium

1,1,2,2-tetrafluoro-6- (1-adamantanecarbonyloxy) - hexane-1-sulfonate, and the like.

Examples of the tetrahydrothiophenium salt include 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium nona. Fluoro-n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiofe Nitro 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium camphorsulfonate , 1- (6-n-Butoxynaphthalen-2-yl Tetrahydrothiophenium trifluoromethanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothio Phenium perfluoro-n-octanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2, 2-tetrafluoroethanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium camphorsulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (3,5-dimethyl- -Hydroxyphenyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (3,5-dimethyl -4-hydroxyphenyl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (3,5-dimethyl-4- Hydroxyphenyl) tetrahydrothiophenium camphorsulfonate and the like.

Examples of the iodonium salt include diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, diphenyliodonium 2-bicyclo [2.2.1] hept-2-yl- 1,1,2,2-tetrafluoroethanesulfonate, diphenyliodonium camphorsulfonate, bis (4-tert-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-tert-butylphenyl) iodonium nonafluoro-n-butanesulfonate, Bis (4-t-butylphenyl) iodonium perfluoro-n-octanesulfonate, bis (4-t-butylphenyl) iodonium 2-bicyclo [2. .1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, bis (4-t- butylphenyl) iodonium camphorsulfonate, and the like.

Examples of N-sulfonyloxyimide compounds include N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (nonafluoro-n-butanesulfonyloxy). ) Bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2 , 3-dicarboximide, N- (2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy) bicyclo [2.2.1] hept- 5-ene-2,3-dicarboximide, N- (2- (3- tetracyclo ^[4.4.0.1 2,5 ^{.1 7,10]} dodecanyl) -1,1-difluoro-ethanone Sulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (camphorsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide etc. can be mentioned.

[B] As the acid generator, a compound represented by the following formula (4) can be used. [B] Since the acid generator has the following structure, the diffusion length of the acid generated by exposure in the resist film is appropriately shortened due to the interaction with the polar structure of the [A] polymer and the like. As a result, the resist performance of the radiation-sensitive composition (I) can be further improved.

In the above formula (4), R ¹⁷ is a monovalent group containing an alicyclic structure having 6 or more ring members or a monovalent group containing an aliphatic heterocyclic structure having 6 or more ring members. R ¹⁸ is a fluorinated alkanediyl group having 1 to 10 carbon atoms. G ⁺ is a monovalent radiation-sensitive onium cation.

Examples of the monovalent group containing an alicyclic structure having 6 or more ring members represented by R ¹⁷ include cycloalkyl groups such as a cyclooctyl group, a cyclononyl group, a cyclodecyl group, and a cyclododecyl group;
A cycloalkenyl group such as a cyclooctenyl group or a cyclodecenyl group;
A polycycloalkyl group such as a norbornyl group, an adamantyl group, a tricyclodecyl group, a tetracyclododecyl group;
Examples thereof include polycycloalkenyl groups such as norbornenyl group and tricyclodecenyl group.

Examples of the monovalent group containing an aliphatic heterocyclic structure having 6 or more ring members represented by R ¹⁷ include a group containing a lactone structure such as a norbornanelactone-yl group;
A group containing a sultone structure such as a norbornane sultone-yl group;
An oxygen atom-containing heterocyclic group such as an oxacycloheptyl group and an oxanorbornyl group;
A nitrogen atom-containing heterocyclic group such as an azacyclohexyl group, an azacycloheptyl group, a diazabicyclooctane-yl group;
And sulfur atom-containing heterocyclic groups such as a thiacycloheptyl group and a thianorbornyl group.

The lower limit of the number of ring members of the group represented by R ¹⁷ is preferably 7, more preferably 8, and even more preferably 9. The upper limit of the number of ring members is preferably 15, more preferably 13, and still more preferably 11. By setting the number of ring members of the group represented by R ¹⁷ within the above range, it is considered that the acid diffusion length is further appropriately shortened. As a result, the resist performance of the radiation-sensitive composition (I) is further improved. Can be improved.

Among these, R ¹⁷ is preferably a monovalent group containing an alicyclic structure having 9 or more ring members and a monovalent group containing an aliphatic heterocyclic structure having 9 or more ring members, an adamantyl group, a hydroxyadamantyl group A norbornanelactone-yl group and a 5-oxo-4-oxatricyclo [4.3.1.1 ^3,8 ] undecan-yl group are more preferred, and an adamantyl group is more preferred.

Examples of the fluorinated alkanediyl group having 1 to 10 carbon atoms represented by R ¹⁸ include one or more hydrogen atoms of an alkanediyl group having 1 to 10 carbon atoms such as a methanediyl group, an ethanediyl group, and a propanediyl group. And a group in which is substituted with a fluorine atom. Among these, SO ₃ ^- fluorinated alkane diyl group which has a fluorine atom to carbon atom is bonded to adjacent groups are preferred, SO ₃ ^- 2 fluorine atoms to the carbon atom adjacent to the group is attached More preferred are fluorinated alkanediyl groups, 1,1-difluoromethanediyl group, 1,1-difluoroethanediyl group, 1,1,3,3,3-pentafluoro-1,2-propanediyl group, 1,1 1,2,2-tetrafluoroethanediyl group, 1,1,2,2-tetrafluorobutanediyl group and 1,1,2,2-tetrafluorohexanediyl group are more preferable.

The monovalent radiation-sensitive onium cation represented by G ⁺ is a cation that decomposes upon exposure to exposure light. In the exposed portion, sulfonic acid is generated from protons generated by the decomposition of the radiation-sensitive onium cation and sulfonate anions. Examples of the monovalent radiation-sensitive onium cation represented by X ⁺ include elements such as S, I, O, N, P, Cl, Br, F, As, Se, Sn, Sb, Te, and Bi. Examples include radiation-sensitive onium cations. Examples of the cation containing S (sulfur) as an element include a sulfonium cation and a tetrahydrothiophenium cation. Examples of the cation containing I (iodine) as an element include an iodonium cation. Among these, a sulfonium cation represented by the following formula (G-1), a tetrahydrothiophenium cation represented by the following formula (G-2), and an iodonium cation represented by the following formula (G-3) preferable.

In the above formula (G-1), R ^a1 , R ^a2 and R ^a3 each independently represent a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted group. aromatic hydrocarbon group having 6 to 12 carbon atoms, represents or is a -OSO ₂ -R ^P or _-SO 2 -R ^Q, or two or more are combined with each other configured ring of these groups . R ^P and R ^Q are each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, or a substituted or unsubstituted alicyclic hydrocarbon group having 5 to 25 carbon atoms. Or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms. k1, k2 and k3 are each independently an integer of 0 to 5. When R ^a1 ~ ^{R a3} and ^{R P} and ^{R Q} are a plurality each of the plurality of ^R a1 ^{~ R a3} and ^{R P} and ^{R Q} may be the same as or different from each other.

In the above formula (G-2), R ^b1 represents a substituted or unsubstituted linear or branched alkyl group having 1 to 8 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon having 6 to 8 carbon atoms. It is a group. k4 is an integer of 0 to 7. If R ^b1 is plural, the plurality of R ^b1 may be the same or different, and plural R ^b1 may represent a constructed ring aligned with each other. R ^b2 is a substituted or unsubstituted linear or branched alkyl group having 1 to 7 carbon atoms, or a substituted or unsubstituted aromatic hydrocarbon group having 6 or 7 carbon atoms. k5 is an integer of 0 to 6. If R ^b2 is plural, the plurality of R ^b2 may be the same or different, and plural R ^b2 may represent a keyed configured ring structure. t is an integer of 0 to 3.

In the above formula (G-3), R ^c1 and R ^c2 each independently represent a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted carbon number of 6 aromatic hydrocarbon group having 1-12, indicating whether it is -OSO ₂ -R ^R or _-SO 2 -R ^S, or two or more are combined with each other configured ring of these groups. R ^R and R ^S each independently represent a substituted or unsubstituted linear or branched alkyl group having 1 to 12 carbon atoms, or a substituted or unsubstituted alicyclic hydrocarbon group having 5 to 25 carbon atoms. Or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 12 carbon atoms. k6 and k7 are each independently an integer of 0 to 5. R ^c1, ^R c2, ^R when ^R and ^{R S} is plural respective plurality of ^R ^c1, R c2, ^{R R} and ^{R S} may have respectively the same or different.

Examples of the unsubstituted linear alkyl group represented by R ^a1 to R ^a3 , R ^b1 , R ^b2 , R ^c1 and R ^c2 include a methyl group, an ethyl group, an n-propyl group, and an n-butyl group. Etc.
Examples of the unsubstituted branched alkyl group represented by R ^a1 to R ^a3 , R ^b1 , R ^b2 , R ^c1 and R ^c2 include i-propyl group, i-butyl group, sec-butyl group, t -A butyl group etc. are mentioned.
Examples of the unsubstituted aromatic hydrocarbon group represented by R ^a1 to R ^a3 , R ^c1 and R ^c2 include aryl groups such as a phenyl group, a tolyl group, a xylyl group, a mesityl group, and a naphthyl group; a benzyl group, Examples include aralkyl groups such as phenethyl group.
Examples of the unsubstituted aromatic hydrocarbon group represented by R ^b1 and R ^b2 include a phenyl group, a tolyl group, and a benzyl group.

Examples of the substituent that may be substituted for the hydrogen atom of the alkyl group and aromatic hydrocarbon group include a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, a hydroxy group, a carboxy group, and a cyano group. Nitro group, alkoxy group, alkoxycarbonyl group, alkoxycarbonyloxy group, acyl group, acyloxy group and the like. Among these, a halogen atom is preferable and a fluorine atom is more preferable.

R ^a1 to R ^a3 , R ^b1 , R ^b2 , R ^c1 and R ^c2 include an unsubstituted linear or branched alkyl group, a fluorinated alkyl group, and an unsubstituted monovalent aromatic hydrocarbon group. , —OSO ₂ —R ″ and —SO ₂ —R ″ are preferred, fluorinated alkyl groups and unsubstituted monovalent aromatic hydrocarbon groups are more preferred, and fluorinated alkyl groups are more preferred. R ″ is an unsubstituted monovalent alicyclic hydrocarbon group or an unsubstituted monovalent aromatic hydrocarbon group.

In the above formula (G-1), k1, k2 and k3 are preferably integers of 0 to 2, more preferably 0 and 1, and even more preferably 0.
In the above formula (G-2), k4 is preferably an integer of 0 to 2, more preferably 0 and 1, and further preferably 1. k5 is preferably an integer of 0 to 2, more preferably 0 and 1, and still more preferably 0.
In the above formula (G-3), k6 and k7 are preferably integers of 0 to 2, more preferably 0 and 1, and still more preferably 0.

Examples of the acid generator represented by the above formula (4) include compounds represented by the following formulas (4-1) to (4-14) (hereinafter referred to as “compounds (4-1) to (4-14)”. Also).

In the above formulas (4-1) to (4-14), G ⁺ has the same meaning as in the above formula (4).

[B] The acid generator is preferably an onium salt compound, more preferably a sulfonium salt, still more preferably a triphenylsulfonium salt, and particularly preferably triphenylsulfonium nonafluoro-n-butanesulfonate and the compound (4-14).

[B] The acid generator is also preferably a polymer in which the structure of an acid generator such as a polymer having a structural unit represented by the following formula (5) is incorporated as a part of the polymer.

In the above formula ^{(5), R 19} is a hydrogen atom or a methyl group. L ³ is a single bond, —COO—, —Ar—, —COO—Ar— or —Ar—OSO ₂ —. Ar is a substituted or unsubstituted arenediyl group having 6 to 20 carbon atoms. R ²⁰ is a fluorinated alkanediyl group having 1 to 10 carbon atoms. G ⁺ is a monovalent radiation-sensitive onium cation.

[B] When the acid generator is a [B] acid generator, the lower limit of the content of the [B] acid generator is preferably 0.1 parts by mass with respect to 100 parts by mass of the [A] polymer. 1 mass part is more preferable, 5 mass parts is further more preferable, 10 mass parts is especially preferable, and 20 mass parts is further especially preferable. As an upper limit of the said content, 50 mass parts is preferable, 40 mass parts or less are more preferable, 35 mass parts or less are more preferable, 32 mass parts is especially preferable. [B] By making content of an acid generator into the said range, the sensitivity of a radiation sensitive composition (I) can further be improved. [B] 1 type (s) or 2 or more types can be used for an acid generator.

<[C] Metal-containing component>
[C] A metal-containing component is a solution in which 0.0001% by mass of only the [C] metal-containing component in terms of metal atom is contained in a measurement solvent having a transmittance of 95% or more in the entire wavelength region of 250 nm to 600 nm ( Hereinafter, the absorbance (hereinafter also referred to as “absorbance (A)”) due to the [C] metal-containing component in the “measurement solution”) is less than 0.01 in the entire wavelength region of 250 nm to 600 nm. It is an ingredient.

The measurement solvent is not particularly limited as long as it has the above properties, and examples thereof include 2-propanol, ethanol, 1-butanol, and ethyl lactate. The measurement solvent may be the same as or different from the [E] solvent of the radiation-sensitive composition (I) described later. In the measurement solution, for example, the [C] metal-containing component in the radiation-sensitive composition (I) is identified by analysis, and the [C] metal-containing component is 0.0001% by mass in terms of metal atom in the measurement solvent. It can be prepared by adding.

The absorbance (A) due to the [C] metal-containing component in the measurement solution is measured, for example, by measuring the absorbance of the measurement solution using the measurement solvent as a reference solvent, and from the absorbance of the measurement solution at each wavelength of 250 nm to 600 nm. It can be determined by subtracting the absorbance of the reference solvent. The absorbance (A) is a value measured by a spectrophotometer such as “V-670” manufactured by JASCO Corporation. The absorbance (A) and the transmittance of the measurement solvent are values per 1 cm of the optical path length.

The radiation-sensitive composition (I) contains a [C] metal-containing component in addition to the [A] polymer and the [B] acid generator, thereby improving sensitivity and nanoedge roughness performance. The reason why the radiation-sensitive composition has the above-described configuration provides the above-mentioned effect is not necessarily clear, but can be inferred as follows, for example. That is, due to the action of the metal of the [C] metal-containing component, secondary electrons are generated from exposure light such as EUV, and an acid is generated from the secondary electrons and the [B] acid generator. As a result, it is considered that the sensitivity of the radiation sensitive composition (I) can be improved. Further, by making the absorbance due to the [C] metal-containing component in the entire wavelength region of the specific range below the above value, unintentional generation of secondary electrons due to the out-of-band light of the [C] metal-containing component It can be considered that the adverse effect of can be suppressed, and as a result, the nano edge roughness performance can be improved.

The upper limit of absorbance (A) is preferably 0.09, more preferably 0.08, and even more preferably 0.07. The lower limit of the absorbance is preferably 0.01, more preferably 0.02, and even more preferably 0.03. By setting the absorbance (A) within the above range, sensitivity and nanoedge roughness performance can be improved in a balanced manner.

[C] The metal-containing component is not particularly limited as long as it is a metal compound having the above properties. Examples of such a component include a metal compound having a combination of a metal atom and a ligand such that the absorbance in the entire wavelength region of 250 nm to 600 nm is not more than the above value. Examples of such a ligand include a ligand derived from a compound not having an aromatic ring, a ligand derived from a compound not having a diketone structure, and the like. [C] When the metal-containing component is a mononuclear metal complex, the ligand of the metal complex is preferably not a carboxylate ligand. [C] When the metal-containing component is a mononuclear complex and the ligand is a carboxylate ligand, the nanoedge roughness performance tends to be lowered.

[C] Examples of metal atoms constituting the metal-containing component include Group 3, Group 4, Group 5, Group 6, Group 8, Group 8, Group 9, Group 10 and Group 11. , Group 12, Group 13, and Group 14 metal atoms. Among these, it is considered that the generation of secondary electrons is further promoted, and from the viewpoint of further improving the sensitivity, metal atoms of Group 4, Group 5, Group 6, Group 12 and Group 14 are used. Are preferred, metal atoms of Group 4, Group 5, Group 6, Group 12 and Group 14 are more preferred, and group 4, Group 5, Group 6 and Group 12 metal atoms are more preferred. .

The metal atom is considered to further promote the generation of secondary electrons, and from the viewpoint of further improving the sensitivity, titanium, zirconium, hafnium, tantalum, tungsten, tin and zinc are preferable, titanium, zirconium, hafnium, Tantalum, tungsten and zinc are more preferred, and zirconium, tantalum, tungsten and zinc are even more preferred.

[C] The metal-containing component preferably includes the [C1] metal-containing component and the [C2] metal-containing component described later.

[A] The lower limit of the content of the [C] metal-containing component with respect to 100 parts by mass of the polymer is 0.1 parts by mass, preferably 0.5 parts by mass, more preferably 1 part by mass, and further 2 parts by mass. Preferably, 4 parts by weight is particularly preferred, and 8 parts by weight is even more preferred. As an upper limit of the said content, 100 mass parts is preferable, 50 mass parts is more preferable, 30 mass parts is further more preferable, 25 mass parts is especially preferable, 17 mass parts is further especially preferable. [C] The sensitivity of a radiation sensitive composition (I) falls that content of a metal containing component is less than 0.1 mass part.

[B] When the acid generator is a [B] acid generator, the lower limit of the content of the [C] compound with respect to 100 parts by mass of the [B] acid generator is preferably 0.5 parts by mass. Is more preferable, 4 parts by mass is further preferable, 8 parts by mass is particularly preferable, 15 parts by mass is further particularly preferable, and 30 parts by mass is most preferable. As an upper limit of the said content, 500 mass parts is preferable, 200 mass parts is more preferable, 150 mass parts is more preferable, 100 mass parts is especially preferable, 60 mass parts is further especially preferable.

[C] By setting the content of the metal-containing component in the above range, the radiation-sensitive composition (I) can further enhance sensitivity and nanoedge roughness performance. The radiation sensitive composition (I) may contain only one type of [C] metal-containing component, or may contain two or more types.

<[D] Acid diffusion controller>
The radiation sensitive composition (I) may contain a [D] acid diffusion controller as needed. [D] The acid diffusion controller controls the diffusion phenomenon in the resist film of the acid generated from the [B] acid generator by exposure, and has an effect of suppressing an undesirable chemical reaction in the non-exposed region. In addition, the storage stability of the radiation-sensitive composition is further improved, and the resolution as a resist is further improved. Furthermore, a change in the line width of the resist pattern due to fluctuations in the holding time from exposure to development processing can be suppressed, and a radiation-sensitive composition excellent in process stability can be obtained. [D] The content of the acid diffusion controller in the radiation-sensitive composition (I) may be a free compound (hereinafter referred to as “[D] acid diffusion controller”) as a part of the polymer. Either the built-in form or both forms may be used.

[D] Examples of the acid diffusion controller include a compound represented by the following formula (6a) (hereinafter also referred to as “nitrogen-containing compound (I)”), a compound having two nitrogen atoms in the same molecule (hereinafter referred to as “nitrogen-containing compound (I)”). "Nitrogen-containing compound (II)"), compounds having three nitrogen atoms (hereinafter also referred to as "nitrogen-containing compound (III)"), amide group-containing compounds, urea compounds, nitrogen-containing heterocyclic compounds, etc. It is done.

In the above formula (6a), R ²¹ , R ²² and R ²³ are each independently a hydrogen atom, an optionally substituted linear, branched or cyclic alkyl group, aryl group or aralkyl group. .

Examples of the nitrogen-containing compound (I) include monoalkylamines such as n-hexylamine; dialkylamines such as di-n-butylamine; trialkylamines such as triethylamine and tri-n-pentylamine; and aromatics such as aniline Group amines and the like.

Examples of the nitrogen-containing compound (II) include ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, and the like.

Examples of the nitrogen-containing compound (III) include polyamine compounds such as polyethyleneimine and polyallylamine; and polymers such as dimethylaminoethylacrylamide.

Examples of the amide group-containing compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone and the like. It is done.

Examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tributylthiourea and the like.

Examples of the nitrogen-containing heterocyclic compound include pyridines such as pyridine and 2-methylpyridine; morpholines such as N-propylmorpholine and N- (undecan-1-ylcarbonyloxyethyl) morpholine; pyrazine, pyrazole and the like. .

In addition, as the nitrogen-containing organic compound, a compound having an acid dissociable group can also be used. Examples of the nitrogen-containing organic compound having such an acid dissociable group include Nt-butoxycarbonylpiperidine, Nt-butoxycarbonylimidazole, Nt-butoxycarbonylbenzimidazole, Nt-butoxycarbonyl-2 -Phenylbenzimidazole, N- (t-butoxycarbonyl) di-n-octylamine, N- (t-butoxycarbonyl) diethanolamine, N- (t-butoxycarbonyl) dicyclohexylamine, N- (t-butoxycarbonyl) diphenylamine Nt-butoxycarbonyl-4-hydroxypiperidine, Nt-amyloxycarbonyl-4-hydroxypiperidine and the like.

Further, as the [D] acid diffusion control agent, a photodegradable base that is exposed to light and generates a weak acid can be used. Examples of the photodegradable base include an onium salt compound that loses acid diffusion controllability by being decomposed by exposure. Examples of the onium salt compound include a sulfonium salt compound represented by the following formula (6b-1), an iodonium salt compound represented by the following formula (6b-2), and the like.

In the above formulas (6b-1) and (6b-2), R ²⁴ to R ²⁸ each independently represents a hydrogen atom, an alkyl group, an alkoxy group, a hydroxy group or a halogen atom. E ⁻ and Q ⁻ are each independently an anion represented by OH ⁻ , R ^β —COO ⁻ , R ^β —SO ₃ ^— or the following formula (6b-3). However, R ( ^beta) is an alkyl group, an aryl group, or an aralkyl group.

In the above formula (6b-3), R ²⁹ is a linear or branched alkyl group having 1 to 12 carbon atoms in which part or all of the hydrogen atoms may be substituted with fluorine atoms, or 1 carbon atom 12 to 12 linear or branched alkoxy groups. u is an integer of 0-2. When u is 2, two R ²⁹ may be the same or different.

Of these, the photodegradable base is preferably a sulfonium salt, more preferably a triarylsulfonium salt, and even more preferably triphenylsulfonium salicylate and triphenylsulfonium 10-camphorsulfonate.

When the radiation-sensitive composition (I) contains a [D] acid diffusion controller, when the [D] acid diffusion controller is a [D] acid diffusion controller, the content of the [D] acid diffusion controller The lower limit of [A] is preferably 0.1 parts by weight, more preferably 0.5 parts by weight, and even more preferably 1 part by weight with respect to 100 parts by weight of the polymer. As an upper limit of the said content, 20 mass parts is preferable, 15 mass parts is more preferable, 10 mass parts is further more preferable, 7 mass parts is especially preferable. [D] By making content of an acid diffusion control agent into the said range, the resolution of the radiation sensitive composition (I), nano edge roughness performance, etc. can be improved.

<[E] solvent>
The radiation sensitive composition (I) usually contains a [E] solvent. [E] The solvent is particularly limited as long as it is a solvent capable of dissolving or dispersing at least the [A] polymer, the [B] acid generator, the [C] compound, and the optionally contained [D] acid diffusion controller. Not. [E] As the solvent, a solvent having a transmittance of 95% or more in the entire wavelength region of 250 nm or more and 600 nm or less is preferable.

[E] Examples of the solvent include alcohol solvents, ether solvents, ketone solvents, amide solvents, ester solvents, hydrocarbon solvents, and the like.

Examples of the alcohol solvent include methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol, tert-butanol, n-pentanol, iso-pentanol, 2-methylbutanol, sec-pentanol, tert-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol , Sec-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec -Monoalcohol solvents such as heptadecyl alcohol, furfuryl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, diacetone alcohol;
Ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2 Polyhydric alcohol solvents such as ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol;
Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl Ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol Monomethyl ether, dipropylene glycol monoethyl ether, polyhydric alcohol partial ether solvents such as dipropylene glycol monopropyl ether.

Examples of ether solvents include dialkyl ether solvents such as diethyl ether, dipropyl ether, and dibutyl ether;
Cyclic ether solvents such as tetrahydrofuran and tetrahydropyran;
And aromatic ring-containing ether solvents such as diphenyl ether and anisole.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-iso-butyl ketone, 2-heptanone, ethyl-n-butyl ketone, methyl-n-hexyl ketone, Chain ketone solvents such as di-iso-butyl ketone and trimethylnonanone:
Cyclic ketone solvents such as cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone and methylcyclohexanone:
Examples include 2,4-pentanedione, acetonylacetone, acetophenone, and the like.

Examples of the amide solvent include cyclic amide solvents such as N, N′-dimethylimidazolidinone and N-methylpyrrolidone;
Examples thereof include chain amide solvents such as N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, and N-methylpropionamide.

Examples of ester solvents include methyl acetate, ethyl acetate, n-propyl acetate, iso-propyl acetate, n-butyl acetate, iso-butyl acetate, sec-butyl acetate, n-pentyl acetate, i-pentyl acetate, sec Acetate solvents such as pentyl, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate;
Ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether Polyhydric alcohol partial ether acetate solvents such as acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate;
Carbonate solvents such as dimethyl carbonate and diethyl carbonate;
Diethyl acetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, iso-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl acetoacetate, ethyl acetoacetate, methyl lactate, ethyl lactate N-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate, diethyl phthalate and the like.

Examples of hydrocarbon solvents include n-pentane, iso-pentane, n-hexane, iso-hexane, n-heptane, iso-heptane, 2,2,4-trimethylpentane, n-octane, iso-octane, cyclohexane , Aliphatic hydrocarbon solvents such as methylcyclohexane;
Fragrances such as benzene, toluene, xylene, mesitylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propylbenzene, iso-propylbenzene, diethylbenzene, iso-butylbenzene, triethylbenzene, di-iso-propylbenzene, n-amylnaphthalene Group hydrocarbon solvents and the like.

Of these, ester solvents and ketone solvents are preferred, polyhydric alcohol partial ether acetate solvents, lactate esters and cyclic ketone solvents are more preferred, and propylene glycol monomethyl ether acetate, ethyl lactate and cyclohexanone are even more preferred. The radiation sensitive composition (I) may contain one or more [E] solvents.

<Other optional components>
In addition to the components [A] to [E], the radiation sensitive composition (I) may contain, for example, a fluorine atom-containing polymer and a surfactant as other optional components. The radiation sensitive composition (I) may contain one or more other optional components.

<Fluorine atom-containing polymer>
The fluorine atom-containing polymer is a polymer having a higher fluorine atom content than the [A] polymer. When the radiation-sensitive composition (I) contains a fluorine atom-containing polymer, when the resist film is formed, the distribution is close to the resist film surface due to the oil-repellent characteristics of the fluorine atom-containing polymer in the resist film. There is a tendency to be unevenly distributed, and it is possible to suppress the acid generator, the acid diffusion controller, and the like from being eluted into the immersion medium during immersion exposure. Further, due to the water-repellent characteristics of this fluorine atom-containing polymer, the advancing contact angle between the resist film and the immersion medium can be controlled within a desired range, and the occurrence of bubble defects can be suppressed. Furthermore, the receding contact angle between the resist film and the immersion medium is increased, and high-speed scanning exposure is possible without leaving water droplets. Thus, the radiation sensitive composition (I) can form a resist film suitable for the immersion exposure method by further containing a fluorine atom-containing polymer.

As a minimum of content of a fluorine atom content polymer, 0.1 mass part is preferred to 100 mass parts of [A] polymer, 0.5 mass part is more preferred, and 1 mass part is still more preferred. As an upper limit of the said content, 20 mass parts is preferable, 15 mass parts is more preferable, and 10 mass parts is further more preferable.

[Surfactant]
Surfactants have the effect of improving coatability, striation, developability, and the like. Examples of the surfactant include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenyl ether, polyoxyethylene n-nonylphenyl ether, polyethylene glycol dilaurate, polyethylene glycol diacrylate. Nonionic surfactants such as stearate; commercially available products include KP341 (Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, no. 95 (above, Kyoeisha Chemical Co., Ltd.), F-top EF301, EF303, EF352 (above, Tochem Products), MegaFuck F171, F173 (above, DIC), Florard FC430, FC431 (above, Sumitomo 3M) Asahi Guard AG710, Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (above, Asahi Glass Industrial Co., Ltd.) Can be mentioned. As an upper limit of content of the said surfactant, 2 mass parts is preferable with respect to 100 mass parts of [A] polymers.

The radiation sensitive composition (I) is preferably for extreme ultraviolet (EUV, vacuum ultraviolet) and electron beam exposure, and more preferably for EUV exposure. The use of the present invention for EUV and electron beam exposure has a particularly great advantage in improving sensitivity and nanoedge roughness performance.

<Method for preparing radiation-sensitive composition (I)>
The radiation-sensitive composition (I) is, for example, a mixture of [A] polymer, [B] acid generator, [C] metal-containing component and other optional components as required, and [E] solvent at a predetermined ratio. Preferably, the resultant mixture can be prepared by filtering with a membrane filter having a pore size of about 0.2 μm. As a minimum of solid content concentration of radiation sensitive composition (I), 0.1 mass% is preferred, 0.5 mass% is more preferred, 1 mass% is still more preferred, and 1.5 mass% is especially preferred. The upper limit of the solid content concentration is preferably 50% by mass, more preferably 30% by mass, further preferably 10% by mass, and particularly preferably 5% by mass.

The radiation sensitive composition (I) can be used for forming a positive pattern using an alkaline developer and for forming a negative pattern using a developer containing an organic solvent.

<Pattern formation method>
The pattern forming method includes a step of forming a film (hereinafter also referred to as “film forming step”), a step of exposing the film (hereinafter also referred to as “exposure step”), and a step of developing the exposed film. (Hereinafter also referred to as “development process”). In the pattern forming method, the film is formed from the radiation-sensitive composition (I). According to the pattern forming method, since the above-mentioned radiation sensitive composition (I) is used, it is possible to form a pattern with high sensitivity and excellent nano edge roughness. Hereinafter, each step will be described.

[Film formation process]
In this step, a film is formed using the radiation-sensitive composition (I). The film can be formed, for example, by applying a radiation sensitive composition on a substrate. Although it does not specifically limit as an application | coating method, For example, appropriate application | coating means, such as spin coating, cast coating, roll coating, can be employ | adopted. Examples of the substrate include a silicon wafer and a wafer coated with aluminum. Specifically, after applying the radiation-sensitive composition so that the resulting film has a predetermined thickness, the solvent in the coating film is volatilized by pre-baking (PB) as necessary.

The lower limit of the average film thickness of the film is preferably 1 nm, more preferably 5 nm, still more preferably 10 nm, and particularly preferably 20 nm. The upper limit of the average thickness is preferably 1,000 nm, more preferably 200 nm, further preferably 100 nm, and particularly preferably 50 nm.

The lower limit of the PB temperature is usually 60 ° C., preferably 80 ° C. As an upper limit of the temperature of PB, it is 140 degreeC normally and 120 degreeC is preferable. The lower limit of the PB time is usually 5 seconds, and preferably 10 seconds. The upper limit of the PB time is usually 600 seconds, and preferably 300 seconds.

[Exposure process]
In this step, the film formed in the film forming step is exposed. In some cases, this exposure is performed by irradiating radiation through a mask having a predetermined pattern through an immersion medium such as water. Examples of the radiation include visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light (EUV, vacuum ultraviolet light; wavelength 13.5 nm), electromagnetic waves such as X-rays and γ rays, and charged particle beams such as electron beams and α rays. It is done. Among these, radiation that emits more secondary electrons from the [B] particles by exposure is preferable, and EUV and electron beams are more preferable.

Further, post-exposure baking (PEB) may be performed after exposure. As a minimum of the temperature of PEB, it is 50 degreeC normally and 80 degreeC is preferable. The upper limit of the PEB temperature is usually 180 ° C, preferably 130 ° C. The lower limit of the PEB time is usually 5 seconds, and preferably 10 seconds. The upper limit of the PEB time is usually 600 seconds, and preferably 300 seconds.

In the present invention, in order to maximize the potential of the radiation-sensitive composition, for example, an organic or inorganic antireflection film can be formed on the substrate to be used. Moreover, in order to prevent the influence of the basic impurity etc. which are contained in environmental atmosphere, a protective film can also be provided, for example on a coating film. When immersion exposure is performed, an immersion protective film may be provided on the film, for example, in order to avoid direct contact between the immersion medium and the film.

[Development process]
In this step, the film exposed in the exposure step is developed. Examples of the developer used for the development include an alkaline aqueous solution and an organic solvent-containing solution.

Examples of the alkaline aqueous solution include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, Ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide (TMAH), pyrrole, piperidine, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [4. 3.0] -5-nonene, and an alkaline aqueous solution in which at least one alkaline compound is dissolved.

The lower limit of the content of the alkaline compound in the alkaline aqueous solution is preferably 0.1% by mass, more preferably 0.5% by mass, and even more preferably 1% by mass. As an upper limit of the said content, 20 mass% is preferable, 10 mass% is more preferable, and 5 mass% is further more preferable.

As the alkaline aqueous solution, a TMAH aqueous solution is preferable, and a 2.38 mass% TMAH aqueous solution is more preferable.

Examples of the organic solvent in the organic solvent-containing liquid include the same organic solvents exemplified as the [D] solvent of the radiation-sensitive composition (I). Of these, ester solvents are preferred, and butyl acetate is more preferred.

The lower limit of the content of the organic solvent in the organic solvent developer is preferably 80% by mass, more preferably 90% by mass, further preferably 95% by mass, and particularly preferably 99% by mass.

These developers may be used alone or in combination of two or more. In general, after development, the substrate is washed with water or the like and dried.

When a alkaline aqueous solution is used as the developer, a positive pattern can be obtained. In addition, when an organic solvent is used as the developer, a negative pattern can be obtained.

<Radiation sensitive composition (II)>
The radiation-sensitive composition (II) contains a [A] polymer, a [B] acid generator, and a [C1] metal-containing component, and the [C1] metal-containing component relative to 100 parts by mass of the [A] polymer. Content is 0.1 mass part or more.

The radiation sensitive composition (II) contains a [A] polymer, a [B] acid generator, and a [C1] metal-containing compound, and the content of the [C1] metal-containing component is not less than the above value. Excellent sensitivity and nano edge roughness performance. The reason why the radiation-sensitive composition (II) has the above-described configuration provides the above-mentioned effects is not necessarily clear, but can be inferred as follows, for example. That is, due to the action of the metal of the [C1] metal-containing component, secondary electrons are generated from exposure light such as EUV, and an acid is generated from the secondary electrons and the [B] acid generator. As a result, the sensitivity of the radiation sensitive composition (II) can be improved. Moreover, according to the [C1] metal-containing component, it is considered that the absorbance due to the [C1] metal-containing component in the entire wavelength region of 250 nm to 600 nm can be made 0.01 or less. Therefore, it is considered that the adverse effect of unintended secondary electrons generated due to the out-of-band light of the [C1] metal-containing component can be suppressed, and as a result, the nano edge roughness performance can be improved.

The radiation-sensitive composition (II) may contain [D] acid diffusion controller and [E] solvent as suitable components, and contains other optional components as long as the effects of the present invention are not impaired. May be. As the [A] polymer, [B] acid generator, [D] acid diffusion controller, [E] solvent and other optional components of the radiation sensitive composition (II), the above radiation sensitive composition (I The same thing as what was described as each component of) can be used. Moreover, what is preferable as each component is the same as that of the said radiation sensitive composition (I). Hereinafter, the [C1] metal-containing component will be described.

[[C1] metal-containing component]
[C1] The metal-containing component is represented by the following formula (1).

In said formula (1), M is a metal atom. R ^A is a group not containing an aromatic ring, substituted or unsubstituted alkyl group, alkoxyalkyl group, (poly) cycloalkyl group, alkoxy (poly) cycloalkyl group, (poly) cycloalkyloxy (poly) cycloalkyl group Or it is the group which combined these groups and the sulfonyl group. m is an integer of 1 to 6. When m is 2 or more, the plurality of R ^A may be the same or different, and the plurality of R ^A are combined with each other, and together with the oxygen atom to which they are bonded and the metal atom to which the oxygen atom is bonded, A ring structure may be formed.

[C1] The metal-containing component is a mononuclear metal complex having m —OR ^A as a ligand. R ^A is an alkyl group, an alkoxyalkyl group, a (poly) cycloalkyl group, an alkoxy (poly) cycloalkyl group, a (poly) cycloalkyloxy (poly) cycloalkyl group, an alkylsulfonyl group, an alkoxyalkylsulfonyl group, (poly ) A cycloalkylsulfonyl group, an alkoxy (poly) cycloalkylsulfonyl group or a (poly) cycloalkyloxy (poly) cycloalkylsulfonyl group, wherein some or all of the hydrogen atoms of these groups have an aromatic ring. May be substituted with no groups. That is, the [C1] metal-containing component is a mononuclear complex in which an alcoholate ligand or a sulfonate ligand represented by —OR ^A is coordinated to a metal atom.

Examples of the metal atom represented by M include Group 3, Group 4, Group 5, Group 6, Group 7, Group 8, Group 9, Group 10, Group 11, Group 12. Group, Group 13, Group 14 metal atoms and the like. Among these, it is considered that the generation of secondary electrons is further promoted, and from the viewpoint of further improving the sensitivity, metal atoms of Group 4, Group 5, Group 6, Group 12 and Group 14 are used. Are preferred, metal atoms of Group 4, Group 5, Group 6, Group 12 and Group 14 are more preferred, and group 4, Group 5, Group 6 and Group 12 metal atoms are more preferred. .

The metal atom is considered to further promote the generation of secondary electrons, from the viewpoint of further improving the sensitivity, from the viewpoint of further promoting the generation of secondary electrons, from the viewpoint of further improving the sensitivity Titanium, zirconium, hafnium, tantalum, tungsten, zinc and tin are preferred, titanium, zirconium, hafnium, tantalum, zinc and tungsten are more preferred, and zirconium, tantalum, tungsten and zinc are more preferred.

Examples of the alkyl group represented by R ^A in the above formula (1) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, and a dodecyl group. Groups and the like.

Examples of the alkoxyalkyl group represented by R ^A include a methoxymethyl group, a methoxyethyl group, a methoxyethyl group, an ethoxymethyl group, a methoxypropyl group, and a 1-methoxy-2-methylpropan-2-yl group. .

Examples of the (poly) cycloalkyl group represented by R ^A include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a cyclodecyl group, a cyclododecyl group, a norbornyl group, an adamantyl group, and a tricyclodecyl group. And tetracyclododecyl group.

Examples of the alkoxy (poly) cycloalkyl group represented by R ^A include a methoxycyclopropyl group, a methoxycyclobutyl group, a methoxycyclopentyl group, a methoxycyclohexyl group, an ethoxycyclopentyl group, and an ethoxycyclohexyl group.

Examples of the (poly) cycloalkyloxy (poly) cycloalkyl group represented by R ^A include a cyclopropyloxycyclopropyl group, a cyclopentyloxycyclopentyl group, a cyclohexyloxycyclohexyl group, and the like.

Examples of the alkylsulfonyl group represented by R ^A include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, a butylsulfonyl group, a pentylsulfonyl group, a hexylsulfonyl group, a heptylsulfonyl group, an octylsulfonyl group, a nonylsulfonyl group, A decylsulfonyl group, a dodecylsulfonyl group, etc. are mentioned.

Examples of the alkoxyalkylsulfonyl group represented by R ^A include a methoxymethylsulfonyl group, a methoxyethylsulfonyl group, a methoxyethylsulfonyl group, an ethoxymethylsulfonyl group, a methoxypropylsulfonyl group, and 1-methoxy-2-methylpropane-2- An ylsulfonyl group etc. are mentioned.

Examples of the (poly) cycloalkylsulfonyl group represented by R ^A include a cyclopropylsulfonyl group, a cyclobutylsulfonyl group, a cyclopentylsulfonyl group, a cyclohexylsulfonyl group, a cyclooctylsulfonyl group, a cyclodecylsulfonyl group, a cyclododecylsulfonyl group, Examples include a norbornylsulfonyl group, an adamantylsulfonyl group, a tricyclodecylsulfonyl group, a tetracyclododecylsulfonyl group, and the like.

Examples of the alkoxy (poly) cycloalkylsulfonyl group represented by R ^A include a methoxycyclopropylsulfonyl group, a methoxycyclobutylsulfonyl group, a methoxycyclopentylsulfonyl group, a methoxycyclohexylsulfonyl group, an ethoxycyclopentylsulfonyl group, and an ethoxycyclohexylsulfonyl group. Is mentioned.

Examples of the (poly) cycloalkyloxy (poly) cycloalkylsulfonyl group represented by R ^A include a cyclopropyloxycyclopropylsulfonyl group, a cyclopentyloxycyclopentylsulfonyl group, a cyclohexyloxycyclohexylsulfonyl group, and the like.

Examples of the ring structure having 4 to 20 ring members formed together with an oxygen atom to which a plurality of R ^A are combined with each other and a metal atom to which the oxygen atom is bonded include a metaradioxycyclopentane structure and a metaradioxycyclohexane structure. , Metaradioxycycloheptane structure, metallaoxy (dioxothiaoxy) cyclopentane structure, metallaoxy (dioxothiaoxy) cyclohexane structure, metallaoxy (dioxothiaoxy) cycloheptane structure, metalladi (dioxothiaoxy) cyclopentane Examples include a structure, a metalladi (dioxothiaoxy) cyclohexane structure, and a metalladi (dioxothiaoxy) cycloheptane structure.

Examples of the group having no aromatic ring for substituting the group of ^RA include halogen atoms such as fluorine atom, chlorine atom, bromine atom and iodine atom;
Ester groups having no aromatic ring such as alkoxycarbonyl group, (poly) cycloalkyloxycarbonyl group, fluorinated alkoxycarbonyl group, fluorinated (poly) cycloalkyloxycarbonyl group, carbonyloxy aliphatic heterocyclic group;
An acyl group having no aromatic ring, such as an alkylcarbonyloxy group, (poly) cycloalkylcarbonyloxy group, fluorinated alkylcarbonyloxy group, fluorinated (poly) cycloalkylcarbonyloxy group, oxycarbonyl aliphatic heterocyclic group;
Examples thereof include a hydroxy group, an amino group, a sulfanyl group, a cyano group, a nitro group, and a carboxy group.

Examples of the aliphatic heterocyclic group in the carbonyloxy aliphatic heterocyclic group and the oxycarbonyl aliphatic heterocyclic group include a lactone ring group, a cyclic carbonate ring group, a sultone ring group, and a cyclic ether ring group. *

As the group having no aromatic ring for substituting the group of ^RA , a halogen atom, an ester group having no aromatic ring and an acyl group having no aromatic ring are preferred, and a fluorine atom, (poly) cycloalkyloxycarbonyl Group, fluorinated alkoxycarbonyl group, (poly) cycloalkylcarbonyloxy group and lactoneoxycarbonyl group are more preferred.

The group of ^RA may have one or more groups that do not have an aromatic ring as a substituent. When having a plurality of substituents, the plurality of substituents may be the same or different.

R ^A is preferably an alkyl group, an alkoxyalkyl group, an alkylsulfonyl group substituted with a group having no aromatic ring, or a (poly) cycloalkylsulfonyl group substituted with a group having no aromatic ring, and an alkyl group , Alkoxyalkyl groups, alkylsulfonyl groups substituted with fluorine atoms, alkylsulfonyl groups substituted with (poly) cycloalkyloxycarbonyl groups, (poly) cycloalkylsulfonyl groups substituted with fluorinated alkoxycarbonyl groups, lactoneoxy An alkylsulfonyl group substituted with a carbonyl group and an alkylsulfonyl group substituted with a fluorine atom and a (poly) cycloalkylcarbonyloxy group are more preferred, and an alkyl group, an alkoxyalkyl group and a trifluoromethylsulfonyl group are more preferred.

M is preferably an integer of 2 to 6, more preferably an integer of 3 to 6, and still more preferably an integer of 4 to 6.

[C1] Examples of the metal-containing component include titanium tetraisopropoxide octylene glycolate, titanium tetra n-propoxide, titanium tetra n-butoxide, etc.
Examples of zirconium compounds include tetraxy ((1-methoxy-2-methylpropan-2-yl) oxy) zirconium, zirconium tetra n-propoxide, zirconium tetra n-butoxide, and the like.
As the hafnium compound, hafnium tetraethoxide, hafnium tetraisopropoxide, etc.
As the tantalum compound, tantalum pentaethoxide, etc.
Examples of the tungsten compound include tungsten hexaethoxide and tungsten pentamethoxide.
Zinc compounds include zinc trifluoromethanesulfonate, zinc pentafluoroethanesulfonate, zinc methanesulfonate, zinc ethanesulfonate, zinc 1,2-bis (cyclohexyloxycarbonyl) ethane-1-sulfonate, 5,6-bis. (Cyclohexyloxycarbonyl) norbornane-2-sulfonic acid zinc, 5,6-bis (2,2,2-trifluoroethoxycarbonyl) norbornane-2-sulfonic acid zinc, 1,2-bis (norbornanelactone-2-yl Examples include zinc oxycarbonyl) ethane-1-sulfonate, zinc 2- (adamantan-1-ylcarbonyloxy) -3,3,3-trifluoropropane-1-sulfonate, and the like.
Examples of the indium compound include indium trifluoromethanesulfonate and indium methanesulfonate.
Examples of the copper compound include copper trifluoromethanesulfonate and copper methanesulfonate.

[C1] The metal-containing component includes titanium tetraisopropoxide octylene glycolate, tetraxy ((1-methoxy-2-methylpropan-2-yl) oxy) zirconium, tungsten hexaethoxide, zinc trifluoromethanesulfonate, Indium trifluoromethanesulfonate, copper trifluoromethanesulfonate, zinc 1,2-bis (cyclohexyloxycarbonyl) ethane-1-sulfonate, zinc 5,6-bis (cyclohexyloxycarbonyl) norbornane-2-sulfonate, 5, 6-bis (2,2,2-trifluoroethoxycarbonyl) norbornane-2-sulfonic acid zinc, 1,2-bis (norbornanelactone-2-yloxycarbonyl) ethane-1-sulfonic acid zinc and 2- (adamantane) -1- Le carbonyloxy) -3,3,3-trifluoro-1-sulfonic acid zinc is preferable.

[A] The lower limit of the content of the [C1] metal-containing component with respect to 100 parts by mass of the polymer is 0.1 parts by mass, preferably 0.5 parts by mass, more preferably 1 part by mass, and further 2 parts by mass. Preferably, 4 parts by weight is particularly preferred, and 8 parts by weight is even more preferred. As an upper limit of the said content, 100 mass parts is preferable, 50 mass parts is more preferable, 30 mass parts is further more preferable, 25 mass parts is especially preferable, 17 mass parts is further especially preferable.

[B] When the acid generator is a [B] acid generator, the lower limit of the content of the [C1] compound with respect to 100 parts by mass of the [B] acid generator is preferably 0.5 parts by mass. Is more preferable, 4 parts by mass is further preferable, 8 parts by mass is particularly preferable, 15 parts by mass is further particularly preferable, and 30 parts by mass is most preferable. As an upper limit of the said content, 500 mass parts is preferable, 200 mass parts is more preferable, 150 mass parts is more preferable, 100 mass parts is especially preferable, 60 mass parts is further especially preferable.

[C1] By setting the content of the metal-containing component in the above range, the radiation-sensitive composition (II) can further enhance sensitivity and nanoedge roughness performance. The radiation-sensitive composition (II) may contain only one type of [C1] metal-containing component or two or more types.

[C1] The metal-containing component can be synthesized, for example, by adding a compound giving an —OR ^A ligand to a metal alkoxide and performing ligand exchange.

<Method for preparing radiation-sensitive composition (II)>
The radiation sensitive composition (II) is, for example, a mixture of [A] polymer, [B] acid generator, [C1] metal-containing component and other optional components as required, and [E] solvent in a predetermined ratio. Preferably, the resultant mixture can be prepared by filtering with a membrane filter having a pore size of about 0.2 μm. As a minimum of solid content concentration of radiation sensitive composition (II), 0.1 mass% is preferred, 0.5 mass% is more preferred, 1 mass% is still more preferred, and 1.5 mass% is especially preferred. The upper limit of the solid content concentration is preferably 50% by mass, more preferably 30% by mass, further preferably 10% by mass, and particularly preferably 5% by mass.

<Radiation sensitive composition (III)>
The radiation sensitive composition (III) contains a [A] polymer, a [B] acid generator, and a [C2] metal-containing component, and the [C2] metal-containing component relative to 100 parts by mass of the [A] polymer. Content is 0.1 mass part or more.

The radiation sensitive composition (III) contains a [A] polymer, a [B] acid generator and a [C2] metal-containing compound, and the content of the [C2] metal-containing component is not less than the above value. Excellent sensitivity and nano edge roughness performance. The reason why the radiation-sensitive composition (III) has the above-described configuration provides the above-mentioned effects is not necessarily clear, but can be inferred as follows, for example. That is, by the action of the metal of the [C2] metal-containing component, secondary electrons are generated from exposure light such as EUV, and an acid is generated from the secondary electrons and the [B] acid generator. As a result, the sensitivity of the radiation sensitive composition (III) can be improved. Moreover, according to the [C2] metal-containing component, it is considered that the absorbance due to the [C2] metal-containing component in the entire wavelength region of 250 nm or more and 600 nm or less can be 0.01 or less. Therefore, it is considered that the adverse effect of unintended secondary electrons due to the out-of-band light of the [C2] metal-containing component can be suppressed, and as a result, the nano edge roughness performance can be improved.

The radiation-sensitive composition (III) may contain [D] acid diffusion controller and [E] solvent as suitable components, and contains other optional components as long as the effects of the present invention are not impaired. May be. As the [A] polymer, [B] acid generator, [D] acid diffusion controller, [E] solvent and other optional components of the radiation sensitive composition (III), the above radiation sensitive composition (I The same thing as what was described as each component of) can be used. Moreover, what is preferable as each component is the same as that of the said radiation sensitive composition (I). Hereinafter, the [C2] metal-containing component will be described.

[[C2] metal-containing component]
[C2] The metal-containing component is an [a] complex or [b] hydrolyzate obtained by mixing [X] metal-containing compound and [Y] organic compound. [C2] Since the metal-containing component is formed as described above, [Y] a structure in which a plurality of metal atoms are crosslinked with a bridging ligand derived from an organic compound and / or —O—. This is considered to be a binuclear metal complex.

([X] metal-containing compound)
[X] The metal-containing compound is a metal compound (I), a hydrolyzate of the metal compound (I), a hydrolysis condensate of the metal compound (I), or a combination thereof.

(Metal compound (I))
The metal compound (I) is a metal compound having an alkoxy group, a (poly) cycloalkyloxy group, an alkylcarbonyloxy group, a (poly) cycloalkylcarbonyloxy group, or a combination thereof. These groups are hydrolyzable groups (hereinafter also referred to as “hydrolyzable groups (Z)”).

Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, octyloxy group, decyloxy group, dodecyloxy group and the like.

Examples of the (poly) cycloalkyloxy group include a cyclopropyloxy group, a cyclobutyloxy group, a cyclopentyloxy group, a cyclohexyloxy group, a cyclooctyloxy group, a cyclodecyloxy group, a cyclododecyloxy group, a norbornyloxy group, Examples thereof include an adamantyloxy group, a tricyclodecyloxy group, and a tetracyclododecyloxy group.

Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, a propylcarbonyloxy group, a butylcarbonyloxy group, a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, a decylcarbonyloxy group, and a dodecylcarbonyl group. An oxy group etc. are mentioned.

(Poly) cycloalkylcarbonyloxy group includes cyclopropylcarbonyloxy group, cyclobutylcarbonyloxy group, cyclopentylcarbonyloxy group, cyclohexylcarbonyloxy group, cyclooctylcarbonyloxy group, cyclodecylcarbonyloxy group, cyclododecylcarbonyloxy group , Norbornylcarbonyloxy group, adamantylcarbonyloxy group, tricyclodecylcarbonyloxy group, tetracyclododecylcarbonyloxy group and the like.

Among the hydrolyzable groups (Z), an alkoxy group and an alkylcarbonyloxy group are preferable, and an alkoxy group is more preferable.

Examples of the metal atom of the metal compound (I) include Group 3, Group 4, Group 5, Group 6, Group 7, Group 8, Group 9, Group 10, Group 11, Group 12. Group, Group 13, Group 14 metal atoms and the like. Among these, metal atoms of Group 4, Group 5, Group 6 and Group 14 are preferred from the viewpoint of further promoting the generation of secondary electrons, and the sensitivity can be further improved. More preferred are Group 4, Group 5 and Group 6 metal atoms.

The metal atom is considered to further promote the generation of secondary electrons, and from the viewpoint of further improving the sensitivity, titanium, zirconium, hafnium, tantalum, tungsten and tin are preferable, and titanium, zirconium, hafnium, tantalum and Tungsten is more preferable, and zirconium, tantalum and tungsten are more preferable.

The metal compound (I) can be used alone or in combination of two or more.

As the metal compound (I), those having 2 to 6 hydrolyzable groups (Z) are preferable, and hafnium tetraisopropoxide is preferable.

Examples of the metal compound (I) include a compound represented by the following formula (A) (hereinafter also referred to as “complex (II)”).

In the above formula (A), M is a metal atom. Y is a hydrolyzable group (Z). x is an integer of 2-6. When x is 2 or more, the plurality of Y may be the same or different.

Examples of the metal compound (I) include titanium tetra n-propoxide, titanium tetra n-butoxide, zirconium tetra n-propoxide, zirconium tetra n-butoxide, hafnium tetraethoxide, hafnium tetraisopropoxide, tantalum pentaethoxide. And tungsten pentamethoxide. Of these, hafnium tetraisopropoxide and tantalum pentaethoxide are preferred.

The hydrolysis condensation reaction of the metal compound (I) or the like can be performed in a solvent containing water, for example. In this hydrolysis condensation reaction, one or more metal compounds (I) can be used. As a minimum of the quantity of water in this hydrolysis condensation reaction, 1 times mole is preferred to the above-mentioned compound, 2 times mole is more preferred, and 3 times mole is still more preferred. The upper limit of the amount is preferably 20 times mole, more preferably 15 times mole, and still more preferably 10 times mole. By setting the amount of water in the hydrolysis-condensation reaction within the above range, the ratio of the hydrolysis-condensation product in the [X] metal-containing compound can be increased, and as a result, the etching resistance of the metal-containing film can be further improved. it can. The hydrolysis condensation reaction may be carried out by adding an acid such as maleic anhydride and / or an acid anhydride in addition to water from the viewpoint of hydrolysis reaction and condensation reaction acceleration.

The solvent used in the reaction (hereinafter also referred to as “reaction solvent 1”) is not particularly limited, and the same solvents as those exemplified as the [E] solvent of the radiation-sensitive composition (I) can be used. Among these, alcohol solvents, ether solvents, ester solvents and hydrocarbon solvents are preferred, monovalent aliphatic alcohols, alkylene glycol monoalkyl ethers, hydroxy acid esters, alkylene glycol monoalkyl ether carboxylic acid esters, Lactone and cyclic ether are more preferable, monovalent aliphatic alcohol having 2 or more carbon atoms, alkylene glycol monoalkyl ether having 6 or more carbon atoms, hydroxy acid ester having 4 or more carbon atoms, alkylene glycol monoalkyl ether having 6 or more carbon atoms Carboxylic acid esters, lactones having 4 or more carbon atoms, and cyclic ethers having 4 or more carbon atoms are more preferable. Methanol, ethanol, isopropanol, n-butanol, propylene glycol monomethyl ether, propylene glycol Over monoethyl ether, propylene glycol monopropyl ether, ethyl lactate, propylene glycol monomethyl ether acetate, and γ- butyrolactone and tetrahydrofuran are particularly preferred.

The reaction solvent 1 is used as it is as the mixed solvent for the synthesis of [a] complex, [b] the reaction solvent for the synthesis of the hydrolyzate or the [E] solvent of the radiation sensitive composition (III) without being removed after the reaction. You can also.

The lower limit of the reaction temperature is preferably 0 ° C, more preferably 10 ° C. As an upper limit of the temperature of the said reaction, 150 degreeC is preferable and 120 degreeC is more preferable. The lower limit of the reaction time is preferably 30 minutes, more preferably 1 hour, and more preferably 2 hours. The upper limit of the reaction time is preferably 24 hours, more preferably 20 hours, and even more preferably 15 hours.

[[Y] organic compound]
[Y] The organic compound is represented by the following formula (L-1).

In the above formula (L-1), R ¹ is n from alkane, alkene, (poly) cycloalkane, (poly) cycloalkene, dialkyl ether, di (poly) cycloalkyl ether or alkyl (poly) cycloalkyl ether. This is a group excluding the hydrogen atom. X is —OH, —COOR ^a , —NCO or —NHR ^a . R ^a is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or a (poly) cycloalkyl group having 3 to 20 carbon atoms. n is an integer of 1 to 4. When n is 2 or more, the plurality of Xs may be the same or different.

Examples of the group obtained by removing n hydrogen atoms from the alkane represented by R ¹ include, for example, when n is 1, an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group,
When n is 2, alkanediyl groups such as methanediyl group, ethanediyl group, propanediyl group, butanediyl group,
When n is 3, alkanetriyl groups such as methanetriyl group, ethanetriyl group, propanetriyl group, butanetriyl group,
Examples of the case where n is 4 include alkanetetrayl groups such as methanetetrayl group, ethanetetrayl group, propanetetrayl group, and butanetetrayl group.

As From alkene represented by R ¹ as a group obtained by removing n hydrogen atoms, for example n is 1, ethenyl group, propenyl group, isopropenyl group, alkenyl groups such as butenyl group,
When n is 2, alkenediyl groups such as ethenediyl group, propenediyl group, butenediyl group, pentenediyl group,
When n is 3, alkenetriyl groups such as ethenetriyl group, propenetriyl group, butenetriyl group,
Examples of the case where n is 4 include alkenetetrayl groups such as ethenetetrayl group, propenetetrayl group, and butenetetrayl group.

Examples of the group obtained by removing n hydrogen atoms from the (poly) cycloalkane represented by R ¹ include, for example, when n is 1, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, norbornyl group, adamantyl group (Poly) cycloalkyl groups such as
When n is 2, (poly) cycloalkanediyl group such as cyclopropanediyl group, cyclobutanediyl group, cyclopentanediyl group, cyclohexanediyl group, norbornanediyl group, adamantanediyl group,
When n is 3, (poly) cycloalkanetriyl group such as cyclopropanetriyl group, cyclobutanetriyl group, cyclopentanetriyl group, cyclohexanetriyl group, norbornanetriyl group, adamantanetriyl group,
When n is 4, (poly) cycloalkanetetrayl group such as cyclopropanetetrayl group, cyclobutanetetrayl group, cyclopentanetetrayl group, cyclohexanetetrayl group, norbornanetetrayl group, adamantanetetrayl group, etc. Can be mentioned.

Examples of the group obtained by removing n hydrogen atoms from the (poly) cycloalkene represented by R ¹ include, for example, when n is 1, a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, a cyclohexenyl group, a norbornenyl group, etc. (Poly) cycloalkenyl group of
When n is 2, (poly) cycloalkenediyl group such as cyclopropenediyl group, cyclobutenediyl group, cyclopentenediyl group, cyclohexenediyl group, norbornenediyl group,
When n is 3, (poly) cycloalkenetriyl group such as cyclopropenetriyl group, cyclobutenetriyl group, cyclopentenetriyl group, cyclohexentriyl group, norbornenetriyl group,
Examples of the case where n is 4 include (poly) cycloalkenetetrayl groups such as cyclopropenetetrayl group, cyclobutenetetrayl group, cyclopentenetetrayl group, cyclohexenetetrayl group, norbornenetetrayl group, and the like.

Examples of the group obtained by removing n hydrogen atoms from the dialkyl ether represented by R ¹ include, for example, when n is 1, an alkoxyalkyl group such as a methoxymethyl group, an ethoxymethyl group, and an ethoxyethyl group.
Examples of the case where n is 2 include alkanediyloxyalkanediyl groups such as methanediyloxymethanediyl group and ethanediyloxyethanediyl group; alkoxyalkanediyl groups such as methoxyethanediyl group and ethoxyethanediyl group.
When n is 3, alkanediyloxyalkanetriyl group such as methanediyloxyethanetriyl group and ethanediyloxyethanetriyl group; alkoxyalkanetriyl group such as methoxyethanetriyl group and ethoxyethanetriyl group etc,
Examples of the case where n is 4 include alkanetriyloxyalkanetriyl groups such as methanetriyloxymethanetriyl group and ethanetriyloxyethanetriyl group.

Examples of the group obtained by removing n hydrogen atoms from di (poly) cycloalkyl ether represented by R ¹ include, for example, when n is 1, cyclopropyloxycyclopropyl group, cyclopentyloxycyclopentyl group, cyclohexyloxycyclohexyl group (Poly) cycloalkyloxy (poly) cycloalkyl groups such as
When n is 2, (poly) cycloalkanediyloxy (poly) cycloalkanediyl group such as cyclopropanediyloxycyclopropanediyl group, cyclopentanediyloxycyclopentanediyl group; cyclopropyloxycyclopropanediyl group, cyclopentyl (Poly) cycloalkyloxy (poly) cycloalkanediyl groups such as oxycyclohexanediyl group and the like can be mentioned.
When n is 3, (poly) cycloalkanediyloxy (poly) cycloalkanetriyl group such as cyclopropanediyloxycyclopropanetriyl group, cyclohexanediyloxycyclohexanetriyl group; cyclopropyloxycyclopropanetriyl group (Poly) cycloalkyloxy (poly) cycloalkanetriyl groups such as cyclohexyloxycyclohexanetriyl group,
Examples of the case where n is 4 include alkanetriyloxyalkanetriyl groups such as cyclopropanetriyloxycyclopropanetriyl group and cyclohexanetriyloxycyclohexanetriyl group.

As the group obtained by removing n hydrogen atoms from the alkyl (poly) cycloalkyl ether represented by R ¹ , for example, when n is 1, methoxy (eg, methoxycyclopropyl group, ethoxycyclopentyl group, methoxycyclohexyl group) Poly) cycloalkyl group; (poly) cycloalkyloxyalkyl group such as cyclopropyloxymethyl group, cyclohexyloxyethyl group,
When n is 2, alkanediyloxy (poly) cycloalkanediyl group such as methanediyloxycyclopropanediyl group, ethanediyloxycyclopentanediyl group; cyclopropyloxymethanediyl group, cyclopentyloxyethanediyl group and the like ( A poly) cycloalkyloxyalkanediyl group,
In the case where n is 3, alkanediyloxy (poly) cycloalkanetriyl group such as ethanediyloxycyclopropanetriyl group, ethanediyloxycyclohexanetriyl group; cyclopropyloxyethanetriyl group, cyclohexyloxyethanetriyl (Poly) cycloalkyloxyalkanetriyl groups such as groups,
Examples of the case where n is 4 include alkanetriyloxyalkanetriyl groups such as ethanetriyloxycyclopropanetriyl group and ethanetriyloxycyclohexanetriyl group.

R ¹ is a group in which 2 to 4 hydrogen atoms have been removed from an alkane, a group in which 1 to 4 hydrogen atoms have been removed from an alkene, or a group in which 2 to 4 hydrogen atoms have been removed from a (poly) cycloalkane A group obtained by removing 1 to 4 hydrogen atoms from (poly) cycloalkene, a group obtained by removing 2 to 4 hydrogen atoms from dialkyl ether, and 2 to 4 hydrogen atoms from di (poly) cycloalkyl ether Preferably a group in which 2 to 4 hydrogen atoms have been removed from an alkyl (poly) cycloalkyl ether, a group in which 2 hydrogen atoms have been removed from an alkane, a group in which 1 hydrogen atom has been removed from an alkene, and A group obtained by removing two hydrogen atoms from a dialkyl ether is more preferable, and an ethenyl group, an isopropenyl group, and an ethanediyloxyethanediyl group are more preferable.

Examples of the alkyl group having 1 to 20 carbon atoms represented by —COOR ^{a of} X and R ^a of —NHR ^a include a methyl group, an ethyl group, a propyl group, a butyl group, and the like. Examples of the (poly) cycloalkyl group having 3 to 20 carbon atoms represented by ^Ra include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a norbornyl group, an adamantyl group, and the like.

R ^a is preferably a hydrogen atom or an alkyl group, more preferably a hydrogen atom, a methyl group or an ethyl group, and even more preferably a hydrogen atom.

X is preferably —OH or —COOH.

[Y] Examples of the organic compound include compounds represented by the following formulas (L-1-1) to (L-1-4) (hereinafter referred to as “compounds (L-1-1) to (L-1-4)”. ) ")) And the like.

In the above formulas (L-1-1) to (L-1-4), R ¹ , R ^a and n are as defined in the above formula (L-1).

As the compound (L-1-1), for example, when n is 1,
Alkyl alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol;
Assuming that n is 2,
Alkylene glycols such as ethylene glycol, propylene glycol, butylene glycol, hexamethylene glycol;
Dialkylene glycols such as diethylene glycol, dipropylene glycol, dibutylene glycol, triethylene glycol, tripropylene glycol;
(Poly) cycloalkylene glycols such as cyclohexanediol, cyclohexanedimethanol, norbornanediol, norbornanedimethanol, adamantanediol, etc.
Assuming that n is 3,
Alkanetriols such as glycerin and 1,2,4-butanetriol;
(Poly) cycloalkanetriols such as 1,2,4-cyclohexanetriol, 1,2,4-cyclohexanetrimethanol;
And trimethylolpropane ethoxylate.
Assuming that n is 4,
Alkanetetraols such as erythritol and pentaerythritol;
And (poly) cycloalkanetetraols such as 1,2,4,5-cyclohexanetetraol.

As the compound (L-1-1), those in which n is 2 and 3 are preferable, alkylene glycol, dialkylene glycol, and alkanetriol are more preferable, those in which n is 2 are further preferable, and dialkylene glycol is particularly preferable. Diethylene glycol is more particularly preferred.

As the compound (L-1-2), when R ^a is a hydrogen atom, for example, n is 1,
Chain saturated monocarboxylic acids such as acetic acid and propionic acid;
Chain unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, trans-2,3-dimethylacrylic acid;
And cycloaliphatic carboxylic acid, norbornane carboxylic acid, alicyclic monocarboxylic acid such as adamantane carboxylic acid, etc.
Assuming that n is 2,
Chain saturated dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid;
Chain unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid;
And alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, norbornane dicarboxylic acid, adamantane dicarboxylic acid, and the like.
Assuming that n is 3,
Chain saturated tricarboxylic acids such as 1,2,3-propanetricarboxylic acid;
And alicyclic tricarboxylic acids such as 1,2,4-cyclohexanetricarboxylic acid, etc.
Assuming that n is 4,
Chain saturated tetracarboxylic acids such as 1,2,3,4-butanetetracarboxylic acid;
Examples thereof include alicyclic tetracarboxylic acids such as 1,2,5,6-cyclohexanetetracarboxylic acid and 2,3,5,6-norbornanetetracarboxylic acid.

As the compound (L-1-2), when R ^a is an alkyl group or a (poly) cycloalkyl group, for example, when n is 1,
Chain saturated monocarboxylic acid esters such as ethyl acetate and cyclopentyl propionate;
Chain unsaturated monocarboxylic acid esters such as methyl acrylate, ethyl methacrylate, ethyl trans-2,3-dimethylacrylate;
And alicyclic monocarboxylic acid esters such as ethyl cyclohexanecarboxylate, cyclohexyl norbornanecarboxylate, methyl adamantanecarboxylate, etc.
Assuming that n is 2,
Linear saturated dicarboxylic acid diesters such as dimethyl oxalate, diethyl malonate, dicyclohexyl succinate, methylcyclopentyl glutarate, diethyl adipate;
Chain unsaturated dicarboxylic acid diesters such as dimethyl maleate, diethyl fumarate, dicyclohexyl itaconate;
And alicyclic dicarboxylic acid diesters such as dimethyl 1,4-cyclohexanedicarboxylate, ethylcyclohexyl norbornanedicarboxylate, diethyl adamantanedicarboxylate, etc.
Assuming that n is 3,
Chain saturated tricarboxylic acid triesters such as

trimethyl

1,2,3-propanetricarboxylic acid;
And alicyclic tricarboxylic acid tri (poly) cycloalkyl such as 1,2,4-cyclohexanetricarboxylic acid tricyclopentyl, etc.
Assuming that n is 4,
Chain saturated tetracarboxylic acid tetraesters such as

tetramethyl

1,2,3,4-butanetetracarboxylate;
Examples thereof include alicyclic tetracarboxylic acid tetraesters such as

tetracyclohexyl

1,2,5,6-cyclohexanetetracarboxylic acid and tetraethyl 2,3,5,6-norbornanetetracarboxylic acid.

As the compound (L-1-2), R ^a is preferably ^a hydrogen atom, n is preferably 1 or 2, and a chain saturated monocarboxylic acid, a chain unsaturated monocarboxylic acid, a chain saturated Dicarboxylic acids and chain unsaturated monocarboxylic acids are preferred, those having n of 1 are more preferred, acetic acid, propionic acid, methacrylic acid, succinic acid and maleic acid are particularly preferred, and methacrylic acid is even more particularly preferred.

As the compound (L-1-3), for example, when n is 1,
Alkyl isocyanates such as methyl isocyanate, ethyl isocyanate, hexyl isocyanate;
(Poly) cycloalkyl isocyanate such as cyclohexyl isocyanate and cyclooctyl isocyanate, and the like.
Assuming that n is 2,
Chain diisocyanates such as ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate;
And alicyclic diisocyanates such as 1,4-cyclohexane diisocyanate and isophorone diisocyanate.
Assuming that n is 3,
Chain triisocyanates such as trimethylene triisocyanate;
And alicyclic triisocyanates such as 1,2,4-cyclohexane triisocyanate, etc.
Assuming that n is 4,
Chain tetraisocyanates such as tetramethylenetetraisocyanate;
And alicyclic tetraisocyanates such as 1,2,4,5-cyclohexanetetraisocyanate.

As the compound (L-1-3), n is preferably 2, chain diisocyanate is more preferable, and hexamethylene diisocyanate is further preferable.

As the compound (L-1-4), for example, when n is 1,
Alkylamines such as methylamine, ethylamine, hexylamine;
(Poly) cycloalkylamines such as cyclohexylamine and cyclooctylamine;
And di (cyclo) alkylamines such as dimethylamine, diethylamine, hexylmethylamine, etc.
Assuming that n is 2,
Alkanediamines such as ethylenediamine, N-methylethylenediamine, N, N′-dimethylethylenediamine, trimethylenediamine, N, N′-dimethyltrimethylenediamine, tetramethylenediamine, N, N′-dimethyltetramethylenediamine;
And cyclohexanediamine such as 1,4-cyclohexanediamine and 1,4-di (aminomethyl) cyclohexane
Assuming that n is 3,
Alkanetriamines such as triaminopropane, N, N ′, N ″ -trimethyltriaminopropane;
And (poly) cycloalkanetriamines such as 1,2,4-triaminocyclohexane
Assuming that n is 4,
Alkanetetraamines such as tetraaminobutane;
And (poly) cycloalkanetetraamines such as 1,2,4,5-tetraaminocyclohexane and 2,3,5,6-tetraaminonorbornane.

As the compound (L-1-4), n is preferably from 2 to 4, more preferably n is 2, alkanediamine is more preferable, and N, N′-dimethylethylenediamine is particularly preferable.

[Y] As the organic compound, the compound (L-1-1) and the compound (L-1-2) are preferable, the compound (L-1-1) in which n is 2, and n is 1 and ^Ra is a hydrogen atom. The compound (L-1-2) is more preferable, dialkylene glycol and chain saturated monocarboxylic acid are more preferable, and diethylene glycol and methacrylic acid are particularly preferable.

([A] complex)
The [a] complex can be suitably synthesized by mixing the [X] metal-containing compound and the [Y] organic compound, for example, in a solvent (hereinafter also referred to as “mixed solvent”). The [X] metal-containing compound and the [Y] organic compound to be mixed can be used alone or in combination of two or more.

The mixed solvent is not particularly limited, and the same solvents as those exemplified as the reaction solvent 1 can be used. Among these, alcohol solvents, ether solvents and ester solvents are preferred, and monovalent aliphatic alcohols, alkylene glycol monoalkyl ethers, hydroxy acid esters, alkylene glycol monoalkyl ether carboxylic acid esters, lactones and cyclic ethers are preferred. More preferably, a monovalent aliphatic alcohol having 2 or more carbon atoms, an alkylene glycol monoalkyl ether having 6 or more carbon atoms, a hydroxy acid ester having 4 or more carbon atoms, an alkylene glycol monoalkyl ether carboxylic acid ester having 6 or more carbon atoms, carbon More preferred are lactones having 4 or more and cyclic ethers having 4 or more carbon atoms, such as methanol, ethanol, isopropanol, n-butanol, propylene glycol monomethyl ether, propylene glycol monoethyl. Ether, propylene glycol monopropyl ether, ethyl lactate, propylene glycol monomethyl ether acetate, and γ- butyrolactone and tetrahydrofuran are particularly preferred.

The mixed solvent can be used as the [E] solvent of the radiation-sensitive composition (III) without being removed after mixing.

The lower limit of the mixing temperature is preferably 0 ° C, more preferably 10 ° C. As an upper limit of the said temperature, 100 degreeC is preferable and 70 degreeC is more preferable. As a minimum of time in mixing, 1 minute is preferred, 10 minutes is more preferred, and 1 hour is more preferred. The upper limit of the time is preferably 8 hours, more preferably 5 hours, and even more preferably 3 hours.

Further, the above-mentioned ethyl lactate or the like may be added to the mixed solution obtained by the above mixing to form a complex [a].

([B] hydrolyzate)
[B] Hydrolytic condensation of the [a] complex for synthesizing the hydrolyzate can be performed, for example, in a solvent containing water. As a minimum of the quantity of water in this hydrolysis condensation reaction, 1 times mole is preferred to the above-mentioned compound, 2 times mole is more preferred, and 3 times mole is still more preferred. The upper limit of the amount is preferably 20 times mole, more preferably 15 times mole, and still more preferably 10 times mole. By setting the amount of water in the hydrolysis-condensation reaction within the above range, [b] the ratio of the hydrolysis-condensation product in the hydrolysis product can be increased, and as a result, the etching resistance of the metal-containing film can be further improved. it can. The hydrolysis condensation reaction may be carried out by adding an acid such as maleic anhydride and / or an acid anhydride in addition to water from the viewpoint of hydrolysis reaction and condensation reaction acceleration.

The solvent used in the hydrolysis condensation reaction (hereinafter also referred to as “reaction solvent 2”) is not particularly limited, and the same solvents as those exemplified as the reaction solvent 1 can be used. Among these, alcohol solvents, ether solvents and ester solvents are preferred, and monovalent aliphatic alcohols, alkylene glycol monoalkyl ethers, hydroxy acid esters, alkylene glycol monoalkyl ether carboxylic acid esters, lactones and cyclic ethers are preferred. More preferably, a monovalent aliphatic alcohol having 2 or more carbon atoms, an alkylene glycol monoalkyl ether having 6 or more carbon atoms, a hydroxy acid ester having 4 or more carbon atoms, an alkylene glycol monoalkyl ether carboxylic acid ester having 6 or more carbon atoms, carbon More preferred are lactones having 4 or more and cyclic ethers having 4 or more carbon atoms, such as methanol, ethanol, isopropanol, n-butanol, propylene glycol monomethyl ether, propylene glycol monoethyl. Ether, propylene glycol monopropyl ether, ethyl lactate, propylene glycol monomethyl ether acetate, and γ- butyrolactone and tetrahydrofuran are particularly preferred.

The reaction solvent 2 can be used as the [E] solvent of the radiation-sensitive composition (III) without being removed after the reaction.

The lower limit of the reaction temperature is preferably 0 ° C, more preferably 10 ° C. As an upper limit of the said temperature, 150 degreeC is preferable and 120 degreeC is more preferable. The lower limit of the reaction time is preferably 30 minutes, more preferably 1 hour, and more preferably 2 hours. The upper limit of the time is preferably 24 hours, more preferably 20 hours, and even more preferably 15 hours.

Further, the above-mentioned ethyl lactate or the like may be added to the reaction solution obtained by the hydrolysis-condensation reaction to obtain a hydrolyzate [b].

[C2] Metal-containing component may be obtained by mixing the obtained [a] complex and [b] hydrolyzate. 1 type (s) or 2 or more types can be used for the [a] complex and [b] hydrolyzate to mix, respectively.

[C2] The metal-containing component is preferably a reaction product of hafnium tetraisopropoxide and methacrylic acid and a reaction product of tantalum pentaethoxide and diethylene glycol.

[C2] The lower limit of the polystyrene-equivalent weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of the metal-containing component is preferably 1,000, more preferably 2,000, and 3,000. More preferably, 5,000 is particularly preferable. The upper limit of Mw is preferably 50,000, more preferably 30,000, still more preferably 20,000, and particularly preferably 15,000.

[C2] The lower limit of the ratio of Mw to the number average molecular weight (Mn) measured by GPC of the metal-containing component is usually 1 and preferably 1.1. The upper limit of the above ratio is usually 5, preferably 3, preferably 2 and more preferably 1.8.

[A] The lower limit of the content of the [C2] metal-containing component with respect to 100 parts by mass of the polymer is 0.1 parts by mass, preferably 0.5 parts by mass, more preferably 1 part by mass, and further 2 parts by mass. Preferably, 4 parts by weight is particularly preferred, and 8 parts by weight is even more preferred. As an upper limit of the said content, 100 mass parts is preferable, 50 mass parts is more preferable, 30 mass parts is further more preferable, 25 mass parts is especially preferable, 17 mass parts is further especially preferable.

[B] When the acid generator is a [B] acid generator, the lower limit of the content of the [C2] compound with respect to 100 parts by mass of the [B] acid generator is preferably 0.5 parts by mass. Is more preferable, 4 parts by mass is further preferable, 8 parts by mass is particularly preferable, 15 parts by mass is further particularly preferable, and 30 parts by mass is most preferable. As an upper limit of the said content, 500 mass parts is preferable, 200 mass parts is more preferable, 150 mass parts is more preferable, 100 mass parts is especially preferable, 60 mass parts is further especially preferable.

[C2] By setting the content of the metal-containing component in the above range, the radiation-sensitive composition (III) can further improve sensitivity and nanoedge roughness performance. The radiation-sensitive composition (III) may contain only one kind of [C2] metal-containing component, or may contain two or more kinds.

<Method for preparing radiation-sensitive composition (III)>
The radiation sensitive composition (III) is, for example, mixed with a predetermined ratio of [A] polymer, [B] acid generator, [C2] metal-containing component and other optional components as required, and [E] solvent. Preferably, the resultant mixture can be prepared by filtering with a membrane filter having a pore size of about 0.2 μm. As a minimum of solid content concentration of radiation sensitive composition (III), 0.1 mass% is preferred, 0.5 mass% is more preferred, 1 mass% is still more preferred, and 1.5 mass% is especially preferred. The upper limit of the solid content concentration is preferably 50% by mass, more preferably 30% by mass, further preferably 10% by mass, and particularly preferably 5% by mass.

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. The measuring method of the physical property value in a present Example is shown below.

[Weight average molecular weight (Mw) and number average molecular weight (Mn)]
Mw and Mn of the polymer are GPC columns (2 G2000HXL, 1 G3000HXL, 1 G4000HXL, Tosoh Corporation), flow rate 1.0 mL / min, elution solvent tetrahydrofuran, sample concentration 1.0 mass%, sample Measurement was performed by gel permeation chromatography (GPC) using monodisperse polystyrene as a standard, using a differential refractometer as a detector under the analysis conditions of an injection amount of 100 μL and a column temperature of 40 ° C.

[ ¹³ C-NMR analysis]
The ¹³ C-NMR analysis for determining the content of the structural unit of the polymer uses a nuclear magnetic resonance apparatus (“JNM-ECX400” manufactured by JEOL Ltd.), uses CDCl ₃ as a measurement solvent, and uses tetramethylsilane ( TMS) was performed as an internal standard.

<[A] Synthesis of polymer>
[A] Monomers used for polymer synthesis are shown below.

[Synthesis Example 1]
55 g (50 mol%) of the above compound (M-1), 45 g (50 mol%) of the above compound (M-2) and 3 g of AIBN were dissolved in 300 g of methyl ethyl ketone, and the reaction temperature was maintained at 78 ° C. in a nitrogen atmosphere. For 6 hours. After the polymerization, the reaction solution was dropped into 2,000 g of methanol to solidify the polymer. Next, this polymer was washed twice with 300 g of methanol, and the resulting white powder was filtered and dried overnight at 50 ° C. under reduced pressure to obtain a polymer (A-1). The polymer (A-1) had Mw of 7,000 and Mw / Mn of 2.10. As a result of ¹³ C-NMR analysis, the content of each structural unit derived from the compound (M-1) and the compound (M-2) was 52 mol% and 48 mol%, respectively.

[Synthesis Example 2]
After dissolving 55 g (42 mol%) of the above compound (M-3), 45 g (58 mol%) of the above compound (M-1), 3 g of AIBN and 1 g of t-dodecyl mercaptan in 150 g of propylene glycol monomethyl ether, The polymerization was carried out for 16 hours while maintaining the reaction temperature at 70 ° C. After the polymerization, the reaction solution was dropped into 1,000 g of n-hexane to coagulate and purify the polymer. Next, 150 g of propylene glycol monomethyl ether was added to the polymer again, and then 150 g of methanol, 37 g of triethylamine and 7 g of water were further added, and a hydrolysis reaction was performed for 8 hours while refluxing at the boiling point. The structural unit derived from -3) was deacetylated. After the reaction, the solvent and triethylamine were distilled off under reduced pressure, and the obtained polymer was dissolved in 150 g of acetone, then dropped into 2,000 g of water to solidify, and the resulting white powder was filtered and filtered at 50 ° C. under reduced pressure. And dried overnight to obtain a polymer (A-2). The polymer (A-2) had Mw of 6,000 and Mw / Mn of 1.90. As a result of ¹³ C-NMR analysis, the content ratios of the structural unit derived from p-hydroxystyrene and the structural unit derived from the compound (M-1) were 50 mol% and 50 mol%, respectively.

[Synthesis Examples 3 and 4]
Polymers (A-3) and (A-4) were synthesized in the same manner as in Synthesis Example 2 except that the types and amounts of monomers shown in Table 1 were used. In Table 1, it shows together about Mw of each obtained polymer, Mw / Mn, and each structural unit content rate.

[Synthesis Example 5]
Glutaraldehyde (50% by mass aqueous solution) 10 g, 3-methoxyphenol 24.8 g and trifluoroacetic acid 37.5 g were dissolved in chloroform 50 mL and refluxed for 48 hours. This solution was added to methanol, and the deposited precipitate was vacuum-dried to obtain 11.3 g of a compound (M-8) represented by the following formula protected with a methoxy group. Next, 8.0 g of this compound, 8.2 g of potassium carbonate, and 0.064 g of tetrabutylammonium bromide were dissolved in 95 mL of N-methylpyrrolidone (NMP) and stirred at 60 ° C. for 3 hours. Further, a solution of 4.3 g of 2-bromoacetyloxy-2-methyladamantane and 5 mL of NMP was added, and the mixture was further stirred at 60 ° C. for 48 hours. The reaction solution was poured into chloroform, washed with a 0.1 M aqueous oxalic acid solution, dried over magnesium sulfate, filtered through celite, and the filtrate was concentrated under reduced pressure. The concentrated solution is added to methanol to precipitate a solid, which is dried under reduced pressure, whereby a compound in which 18% of the hydroxyl groups of (M-8) are protected with a 2-acetyloxy-2-methyladamantane group ( 5.9 g of A-5) was obtained.

<[C] Synthesis of metal-containing component>
[Synthesis Example 6]
Hafnium tetraisopropoxide (5.0 g) was dissolved in 10.0 g of tetrahydrofuran, 20.0 g of methacrylic acid was added thereto, and the mixture was stirred at 60 ° C. for 24 hours. This solution was mixed with 100 g of hexane, and the resulting precipitate was collected, washed with hexane, and then vacuum dried to obtain 3.1 g of a metal-containing component (C-6).

[Synthesis Example 7]
Hafnium tetraisopropoxide (5.0 g) was dissolved in 10.0 g of tetrahydrofuran, 20.0 g of benzoic acid was added thereto, and the mixture was stirred at 60 ° C. for 24 hours. This solution was mixed with 100 g of hexane, and the resulting precipitate was collected, washed with hexane and vacuum dried to obtain 3.1 g of a metal-containing component (C-7).

[Synthesis Example 8]
After mixing 10.0 g of tantalum pentaethoxide and 100 g of tetrahydrofuran and stirring for 10 minutes at 25 ° C., 6.5 g of diethylene glycol was mixed, followed by heating and stirring at 60 ° C. for 4 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, the solvent was once removed by an evaporator, and the non-volatile component was further dried under reduced pressure to obtain a metal-containing component (C-10).

[Synthesis Example 9]
(Acetylacetonato) 4.6 g of tantalum (V) tetraethoxide and 100 g of tetrahydrofuran were mixed and stirred for 10 minutes at 25 ° C., then 2.1 g of diethylene glycol was mixed, and heated and stirred at 60 ° C. for 4 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and the solvent was once removed by an evaporator. The nonvolatile component was further dried under reduced pressure to obtain a metal-containing component (C-11).

The [C] metal-containing components ((C-1) to (C-13)) used for the preparation of the radiation-sensitive composition are shown in Table 2 below.

[Absorbance measurement]
A measurement solution prepared by adding the [C] metal-containing component and the measurement solvent shown in Table 2 below, and adding only the [C] metal-containing component to the measurement solvent so as to be 0.0001% by mass in terms of metal atoms. Absorbance was measured using a spectrophotometer (“V-670” manufactured by JASCO Corporation) using the same solvent as the measurement solvent as a reference solvent. At each wavelength of 250 nm to 600 nm, the absorbance of the reference solvent was subtracted from the absorbance of the measurement solution, and the absorbance due to the [C] metal-containing component was determined. If the measured absorbance value is less than 0.01 in the entire wavelength region of wavelengths from 250 nm to 600 nm, “A” indicates that the wavelength at which the absorbance is 0.01 or more in the wavelength region of 250 nm to 600 nm is small. The case was evaluated as “B”. The evaluation results are shown in Table 2 below. In addition, it was confirmed that the transmittance of the solvent used for the measurement of the absorption analysis was 95% or more in the entire wavelength region having a wavelength of 250 nm to 600 nm.

<Preparation of radiation-sensitive composition>
Components other than the [A] polymer and the [C] metal-containing component used for the preparation of the radiation-sensitive composition are shown below.

[[B] acid generator]
B-1: Triphenylsulfonium nonafluoro-n-butanesulfonate (compound represented by the following formula (B-1))
B-2: Triphenylsulfonium 2- (4-oxo-adamantan-1-ylcarbonyloxy) -1,1,3,3,3-pentafluoropropane-1-sulfonate (represented by the following formula (B-2) Compound)

[[D] acid diffusion controller]
D-1: Triphenylsulfonium salicylate (compound represented by the following formula (D-1))
D-2: 2,4,5-triphenylimidazole (compound represented by the following formula (D-2))

[[E] solvent]
E-1: Propylene glycol monomethyl ether acetate E-2: Ethyl lactate E-3: Cyclohexanone

[Example 1]
[A] 100 parts by mass of (A-1) as a polymer, [B] 27 parts by mass of (B-1) as an acid generator, [C] 5 parts by mass of (C-1) as a metal-containing component, [D] 2.6 parts by weight of (D-1) as an acid diffusion controller and 4,300 parts by weight of (E-1) and 1,900 parts by weight of (E-2) as a solvent are mixed. The resulting mixed solution was filtered through a membrane filter having a pore size of 0.20 μm to prepare a radiation sensitive composition (R-2).

[Examples 2 to 7 and Comparative Examples 1 to 11]
Radiation sensitive compositions (R-1) and (R-3) to (R-18) were prepared in the same manner as in Example 1 except that the components of the types and blending amounts shown in Table 3 were used. did. “-” In Table 3 indicates that the corresponding component was not used.

<Pattern formation>
[Example 1]
In the “Clean Track ACT-8” of Tokyo Electron, the radiation sensitive composition (R-2) prepared in Example 1 was spin coated on a silicon wafer, and PB was performed at 130 ° C. for 60 seconds. A film having an average thickness of 50 nm was formed. Subsequently, patterning was performed using a vacuum ultraviolet exposure apparatus (NA: 0.3, dipole illumination). Next, PEB was performed in the clean track ACT-8 at 120 ° C. for 60 seconds, and then developed using a 2.38 mass% tetramethylammonium hydroxide aqueous solution at 23 ° C. for 1 minute by the paddle method. Washed with water and dried to form a pattern.

[Examples 2 to 7 and Comparative Examples 1 to 11]
Each pattern was formed in the same manner as in Example 1 except that the radiation-sensitive composition shown in Table 4 below was used.

<Evaluation>
The sensitivity and nanoedge roughness performance of the prepared radiation sensitive composition and the formed positive pattern were evaluated according to the following methods. The evaluation results are shown in Table 4 below.

[sensitivity]
In patterning using vacuum ultraviolet rays, a line-and-space pattern (1L1S) including a line portion having a line width of 35 nm and a space portion having a space of 35 nm formed by adjacent line portions is formed in a one-to-one line width. The exposure amount was the optimum exposure amount, and this optimum exposure amount was the sensitivity (mJ / cm ² ).

[Nano edge roughness performance]
The line pattern of the formed line and space pattern (1L1S) was observed using a high resolution FEB length measuring device (“S-9380” manufactured by Hitachi, Ltd.). Arbitrary 20 points in the substrate are observed, and as for the observed shape, as shown in FIG. 1 and FIG. 2, irregularities generated along the lateral surface 2a of the line part 2 of the resist film formed on the silicon wafer 1 The difference “ΔCD” between the line width at the most remarkable point and the design line width of 35 nm was measured, and the average value of this ΔCD was defined as nano edge roughness performance (nm). When the nano edge roughness performance is 4.0 nm or less, it is “AA (very good)”, and when it exceeds 4.0 nm and 6.0 nm or less, it is “A (good)” and exceeds 6.0 nm. Was judged as “B (defect)”. In addition, the unevenness | corrugation shown in FIG.1 and FIG.2 is exaggerated rather than actually.

From the results of patterning by the vacuum ultraviolet exposure apparatus shown in Table 4, it is recognized that patterning with high sensitivity is possible by applying the radiation-sensitive composition of the present invention, and the nano edge roughness of the pattern is also good. It was.

1 Silicon wafer 2 Pattern line 2a Pattern side

Claims

A polymer having a first structural unit containing an acid-dissociable group,
A radiation-sensitive acid generator and a radiation-sensitive composition containing a metal-containing component,
The content of the metal-containing component with respect to 100 parts by mass of the polymer is 0.1 parts by mass or more,
Absorbance due to the metal-containing component in a solution in which only 0.001% by mass of the metal-containing component in terms of metal atom is contained in a measurement solvent having a transmittance of 95% or more in the entire wavelength region of 250 nm to 600 nm. The radiation-sensitive composition is characterized by being less than 0.01 in the entire wavelength region of 250 nm or more and 600 nm or less.
A polymer having a first structural unit containing an acid-dissociable group,
A radiation-sensitive acid generator and a radiation-sensitive composition containing a metal-containing component,
The content of the metal-containing component with respect to 100 parts by mass of the polymer is 0.1 parts by mass or more,
The said metal containing component is represented by following formula (1), The radiation sensitive composition characterized by the above-mentioned.

(In Formula (1), M is a metal atom. RA is a substituted or unsubstituted alkyl group, alkoxyalkyl group, (poly) cycloalkyl group, alkoxy (poly) with a group having no aromatic ring. A cycloalkyl group, a (poly) cycloalkyloxy (poly) cycloalkyl group, or a combination of these groups and a sulfonyl group, m is an integer of 1 to 6. When m is 2 or more, R A may be the same or different, and a plurality of R A may be combined with each other to form a ring structure having 4 to 20 ring members together with the oxygen atom to which they are bonded and the metal atom to which the oxygen atom is bonded. Good.)
A polymer having a first structural unit containing an acid-dissociable group,
A radiation-sensitive acid generator and a radiation-sensitive composition containing a metal-containing component,
The content of the metal-containing component with respect to 100 parts by mass of the polymer is 0.1 parts by mass or more,
The metal-containing component is a metal compound (I) having an alkoxy group, a (poly) cycloalkyloxy group, an alkylcarbonyloxy group, a (poly) cycloalkylcarbonyloxy group or a combination thereof, and a hydrolyzate of the metal compound (I). Complex obtained by mixing a decomposition product, a metal-containing compound which is a hydrolysis condensate of the above metal compound (I) or a combination thereof, and at least one organic compound represented by the following formula (L-1) Alternatively, a radiation-sensitive composition obtained by hydrolytic condensation of this complex.

(In the formula (L-1), R 1 represents n from alkane, alkene, (poly) cycloalkane, (poly) cycloalkene, dialkyl ether, di (poly) cycloalkyl ether or alkyl (poly) cycloalkyl ether. X is —OH, —COOR a , —NCO or —NHR a, where R a is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or 3 to 20 carbon atoms. (N) is an integer of 1 to 4. When n is 2 or more, a plurality of Xs may be the same or different.
The metal atoms constituting the metal-containing component are Group 3, Group 4, Group 5, Group 6, Group 7, Group 8, Group 9, Group 10, Group 11, Group 12. The radiation-sensitive composition according to claim 1, claim 2 or claim 3, which is a group 13 or group 14 metal atom.
The radiation-sensitive composition according to claim 4, wherein the metal atom is titanium, zirconium, hafnium, tantalum, tungsten or zinc.
The radiation-sensitive composition according to any one of claims 1 to 5, wherein the first structural unit is represented by the following formula (2-1) or the following formula (2-2).

(In the formula (2-1), R 2 is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. R 3 is a monovalent hydrocarbon group having 1 to 20 carbon atoms. R 4 And R 5 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms, or a ring member having 3 to 20 ring members composed of these groups together with the carbon atom to which they are bonded. Represents an alicyclic structure.
In formula (2-2), R 6 represents a hydrogen atom or a methyl group. L 1 is a single bond, —COO— or —CONH—. R 7 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. R 8 and R 9 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms or a monovalent oxyhydrocarbon group having 1 to 20 carbon atoms. )
The radiation sensitive composition according to any one of claims 1 to 6, wherein the polymer further includes a second structural unit represented by the following formula (3).

(In Formula (3), R 10 is a hydrogen atom or a methyl group. L 2 is a single bond or a divalent organic group having 1 to 20 carbon atoms. R 11 is a C 1-20 carbon atom. A monovalent organic group, p is an integer of 0 to 2. q is an integer of 0 to 9. When q is 2 or more, a plurality of R 11 may be the same or different. r is an integer of 1 to 3.)
The radiation sensitive composition according to any one of claims 1 to 5, wherein the polymer is calixarene.
The radiation-sensitive composition according to any one of claims 1 to 8, wherein a content of the metal-containing component with respect to 100 parts by mass of the polymer is 1 part by mass or more and 100 parts by mass or less.
The radiation-sensitive composition according to any one of claims 1 to 9, which is used for exposure to extreme ultraviolet rays or electron beams.
Forming a film;
A step of exposing the film; and a step of developing the exposed film,
The pattern formation method which forms the said film | membrane with the radiation sensitive composition of any one of Claims 1-10.
The pattern forming method according to claim 11, wherein the developer used in the developing step is an alkaline aqueous solution.
The pattern forming method according to claim 11, wherein the developer used in the developing step is an organic solvent-containing solution.
The pattern forming method according to claim 11, wherein the radiation used in the exposure step is extreme ultraviolet rays or an electron beam.