WO2015098398A1

WO2015098398A1 - Pattern formation method, method for producing electronic device, electronic device, and aqueous developing solution

Info

Publication number: WO2015098398A1
Application number: PCT/JP2014/081095
Authority: WO
Inventors: 雄一郎榎本; 亮介上羽; 三千紘白川; 創古谷; 研由後藤; 雅史小島
Original assignee: 富士フイルム株式会社
Priority date: 2013-12-26
Filing date: 2014-11-25
Publication date: 2015-07-02
Also published as: TW201526077A; JP2015125321A

Abstract

This pattern formation method involves: a step for forming an actinic-ray sensitive or radiation sensitive film by using an actinic-ray sensitive or radiation sensitive resin composition containing a resin which produces an acidic functional group as a result of decomposition caused by the activity of an acid; a step for exposing the actinic-ray sensitive or radiation sensitive film to light; and an alkaline developing step for developing the exposed actinic-ray sensitive or radiation sensitive film by using an aqueous developing solution which contains a basic compound having two or more basic functional groups.

Description

Pattern forming method, electronic device manufacturing method, electronic device, and aqueous developer

The present invention relates to a pattern forming method used in a semiconductor manufacturing process such as an IC, a circuit board such as a liquid crystal or a thermal head, and other photofabrication lithography processes, and an aqueous system used in this pattern forming method. The present invention relates to a developer, an electronic device manufacturing method, and an electronic device. The present invention particularly relates to a pattern forming method suitable for exposure with an ArF exposure apparatus and an immersion projection exposure apparatus using far ultraviolet light having a wavelength of 300 nm or less as a light source, an aqueous developer used in this pattern forming method, The present invention relates to an electronic device manufacturing method and an electronic device.

Since the development of resists for KrF excimer laser (248 nm), an image forming method called chemical amplification has been used as an image forming method for resists in order to compensate for sensitivity reduction due to light absorption. An example of a positive-type chemical amplification image forming method is as follows. Excimer laser, electron beam, extreme ultraviolet light, etc. exposes the acid generator in the exposed area to decompose to produce acid. In this image forming method, an alkali-insoluble group is changed to an alkali-soluble group by using a generated acid as a reaction catalyst, and an exposed portion is removed with an alkali developer. At present, an aqueous developer of 2.38% by mass tetramethylammonium hydroxide (TMAH) is widely used as an alkaline developer as a standard solution.

To reduce the size of semiconductor elements, the exposure light source has become shorter and the projection lens has a higher numerical aperture (high NA). Currently, an exposure machine using an ArF excimer laser having a wavelength of 193 nm as a light source has been developed. ing. When an ArF excimer laser is used as an exposure light source, a compound having an aromatic group essentially exhibits a large absorption in the 193 nm region. Therefore, an ArF excimer laser resist containing a resin having an alicyclic hydrocarbon structure has been developed. (For example, refer to Patent Document 1). Further, as a technique for further increasing the resolving power, a method of filling a high refractive index liquid (hereinafter also referred to as “immersion liquid”) between the projection lens and the sample (ie, immersion method) has been proposed. In addition, EUV lithography in which exposure is performed with ultraviolet light having a shorter wavelength (13.5 nm) has also been proposed.

In recent years, a pattern forming method including an organic solvent development process in which development is performed using a developer containing an organic solvent (hereinafter referred to as “organic solvent developer”) is also being developed. As a double patterning technique for increasing resolution, an alkali development process in which development is performed using an alkali developer and a double development process in which an organic solvent development process is performed are disclosed. The double development process by “alkaline development-organic solvent development” will be described with reference to FIG. 2. By exposure, the polarity of the resin in the resist composition becomes high in the region where the light intensity is high, and the light intensity is low. By utilizing the fact that the region is kept at a low polarity, the high exposure region (exposed portion) 11 of the resist film is dissolved in an alkali developer (see FIGS. 2A and 2B), and the low exposure amount is obtained. By dissolving the region (unexposed portion) 13 in the organic solvent developer, the intermediate exposure amount region (intermediate exposed portion) 12 remains undissolved and removed by development, and has a half-pitch of the mask for exposure. A space pattern is formed (see FIGS. 2B and 2C).

JP-A-9-73173 JP 2008-292975 A

In the double development process by “alkaline development-organic solvent development”, when the intermediate exposure amount region (hereinafter referred to as “intermediate exposure portion”) has insufficient dissolution contrast, the residual amount of the pattern is small, resulting in roughness. The problem is that (line width roughness: LWR) is large.

Further, the LWR problem requires further improvement not only in the pattern formed by the double development process but also in the pattern formed by the single development process by alkali development.

An object of the present invention is to provide a pattern forming method capable of forming a pattern with improved LWR, an aqueous developer used in this method, a method for manufacturing an electronic device, and an electronic device. The present invention also provides a pattern forming method capable of forming a pattern having good pattern survivability and improved LWR in pattern formation including a double development process by an alkali development process and an organic solvent development process. It is an object of the present invention to provide an aqueous developer, a method for producing an electronic device, and an electronic device used in the above.

In one aspect, the present invention is as follows.
[1] A step of forming an actinic ray-sensitive or radiation-sensitive film using an actinic ray-sensitive or radiation-sensitive resin composition containing a resin that decomposes by the action of an acid to generate an acidic functional group,
Exposing the actinic ray-sensitive or radiation-sensitive film; and
An alkali development step of developing the exposed actinic ray-sensitive or radiation-sensitive film using an aqueous developer containing a basic compound having two or more basic functional groups,
A pattern forming method including:

[2] The pattern forming method according to [1], further including an organic development step of developing the actinic ray-sensitive or radiation-sensitive film using a developer containing an organic solvent after the alkali development step.

[3] The pattern forming method according to [1] or [2], wherein the basic compound is a compound capable of preparing an aqueous solution having a base normality of 0.1 N or more at 23 ° C.

[4] Any one of [1] to [3], wherein the basic compound is a compound having at least one selected from a tertiary amino group and a quaternary ammonio group as a basic functional group. The pattern forming method according to item.

[5] The pattern forming method according to [4], wherein the basic compound is a compound having at least one quaternary ammonio group as a basic functional group.

[6] The pattern forming method according to any one of [1] to [5], wherein the basic compound is a compound having three or more basic functional groups.

[7] Between the exposure step and the alkali development step, between the heating step A for heating the actinic ray-sensitive or radiation-sensitive film after exposure, and between the alkali development step and the organic development step. A heating step B for heating the actinic ray-sensitive or radiation-sensitive film after alkali development, wherein the heating temperature in the heating step B is 30 ° C. higher than the heating temperature in the heating step A, [2] to [ [6] The pattern forming method according to any one of [6].

[8] The exposure process according to any one of [1] to [7], wherein the exposure step is a step in which a liquid is brought into contact with the actinic ray-sensitive or radiation-sensitive film and exposure is performed through the liquid. Pattern forming method.

[9] A method for manufacturing an electronic device, comprising the pattern forming method according to any one of [1] to [8].
[10] An electronic device manufactured by the method for manufacturing an electronic device according to [9].

[11] A step of forming an actinic ray-sensitive or radiation-sensitive film using an actinic ray-sensitive or radiation-sensitive resin composition containing a resin that decomposes by the action of an acid to produce an acidic functional group, the above-mentioned activity An aqueous developer used in a pattern forming method including a step of exposing a light sensitive or radiation sensitive film and an alkali developing step of developing the exposed actinic light sensitive or radiation sensitive film using an aqueous developer. An aqueous developer containing a basic compound having two or more basic functional groups.

[12] The aqueous developer according to [11], wherein the basic compound is a compound capable of preparing an aqueous solution having a normality of 0.1 N or more at 23 ° C.
[13] The aqueous system according to [11] or [12], wherein the basic compound is a compound having at least one selected from a tertiary amino group and a quaternary ammonio group as a basic functional group. Developer.
[14] The aqueous developer according to [13], wherein the basic compound is a compound having at least one quaternary ammonio group as a basic functional group.
[15] The aqueous developer according to any one of [11] to [14], wherein the basic compound is a compound having three or more basic functional groups.

According to the present invention, it is possible to provide a pattern forming method capable of forming a pattern with improved LWR, an aqueous developer used in this method, a method for manufacturing an electronic device, and an electronic device. Further, according to the present invention, in a pattern formation including a double development process by an alkali development process and an organic solvent development process, a pattern formation method capable of forming a pattern with good pattern survivability and improved LWR, It has become possible to provide an aqueous developer used in the method, a method for producing an electronic device, and an electronic device.

The image figure of the pattern cross section for demonstrating the mechanism of a roughness characteristic improvement in the pattern formation method which concerns on this invention. The figure for demonstrating a double image development process roughly.

Hereinafter, embodiments of the present invention will be described in detail.
In the notation of a group (atomic group) in this specification, a notation that does not indicate substitution or non-substitution refers to a group (atomic group) having a substituent together with a group (atomic group) having no substituent. Is also included. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

Here, “active light” or “radiation” means, for example, an emission line spectrum of a mercury lamp, far ultraviolet rays represented by an excimer laser, extreme ultraviolet rays (EUV light), X-rays, electron beams (EB), and the like. . In the present invention, light means actinic rays or radiation.

In addition, “exposure” here means not only exposure by far ultraviolet rays, extreme ultraviolet rays, X-rays, EUV light, etc. represented by mercury lamps and excimer lasers, but also particle beams such as electron beams and ion beams, unless otherwise specified. Include drawing in exposure.

Hereinafter, each step included in the pattern forming method of the present invention will be described in detail, and then the actinic ray-sensitive or radiation-sensitive resin composition suitably used for this pattern forming method will be described in detail.

<Pattern formation method>
As described above, the pattern forming method of the present invention includes:
Forming an actinic ray-sensitive or radiation-sensitive film using an actinic ray-sensitive or radiation-sensitive resin composition containing a resin that decomposes by the action of an acid to produce an acidic functional group;
Exposing the actinic ray-sensitive or radiation-sensitive film; and
An alkali development step of developing the exposed actinic ray-sensitive or radiation-sensitive film using an aqueous developer containing a basic compound having two or more basic functional groups,
including.
In one embodiment, the pattern forming method of the present invention may include a development step a plurality of times. For example, after the alkali development step, the actinic ray sensitivity or radiation sensitivity may be obtained using a developer containing an organic solvent. It is preferable to include an organic development step for developing the film.

In another form, the pattern forming method of the present invention may include a heating step, and may further include a heating step a plurality of times.
Moreover, the pattern formation method of this invention may include the rinse process in another form.
Moreover, the pattern formation method of this invention may include the exposure process in multiple times in other forms.
Hereinafter, each step will be described. First, the development process will be described.

[Development process]
The pattern forming method of the present invention uses an aqueous developer containing a basic compound having two or more basic functional groups (hereinafter also referred to as “polyvalent base compound” or “basic compound of the present invention”). The first feature is that it includes an alkali developing step of developing the actinic ray-sensitive or radiation-sensitive film after exposure.

Currently, an aqueous developer of TMAH (monovalent base) is widely used as an alkaline developer for photoresists. By changing this to an aqueous developer of a polyvalent base compound, pattern sidewalls can be obtained. It has been found by the present inventors that the roughness is improved. Furthermore, in pattern formation including a double development process by “alkali development-organic solvent development” (hereinafter simply referred to as “double development process”), an aqueous developer containing a polyvalent base compound is used as an alkali developer. As a result, it has been found that, in addition to improving the roughness of the pattern side wall, the pattern survivability is improved.

The improvement of the roughness characteristics of the pattern by changing the alkaline developer for photoresist from an aqueous developer of TMAH to an aqueous developer of a polybasic compound is presumed to be due to the following mechanism. FIG. 1 is an image diagram for explaining this mechanism, and will be described with reference to this. That is, TMAH is a monovalent base, whereas the basic compound of the present invention is a polyvalent base. Therefore, the polyvalent base compound 3 in the developer acting on the side wall of the pattern (unexposed portion) 1 is Furthermore, it acts on the deprotected acid group in the resin (deprotected resin) 2 in the exposed area, and the side wall of the pattern 1 is covered with the deprotected resin 2 as shown in FIG. It is thought that it was improved.

Further, in the double development process, as described above, the intermediate exposed portion remains without being dissolved and removed by development. However, when the dissolution contrast of the intermediate exposed portion is insufficient, the residual amount of the pattern is small, resulting in roughness. Large is a problem. By changing the alkaline developer for the photoresist from an aqueous developer of TMAH to an aqueous developer of a polybasic compound, the roughness of the pattern side wall is improved, and the pattern survivability is improved as follows. This is presumed to be due to the mechanism. That is, an acid group is generated in the intermediate exposure portion by exposure and post-exposure heating (Post Exposure Bake: PEB), and this acid group is neutralized by contact with a base in the developer during alkali development to form a salt. To do. In addition to polarity conversion by deprotection, it is considered that this salt formation also contributes to a decrease in dissolution rate during organic solvent development in the intermediate exposure area. By using a polyvalent base as the base of the developer, it is presumed that the degree of insolubilization will be higher due to multi-point salt formation between the acid group and base of the resin in the intermediate exposure part. .

When the pattern forming method of the present invention includes an organic development step after the alkali development step as the development step, the alkali development step is referred to as “first development step”, and the developer used therein is represented as “first developer”. In some cases, the organic development step is referred to as “second development step”, and the developer used therein is referred to as “second developer”.

・ Alkali development process (first development process)
In the alkali development step, an aqueous developer containing a polybasic compound having two or more basic functional groups is used as the developer. Here, “water-based” means that water is contained as a main component, and specifically, it is intended that the content of water is more than 50 mass% with respect to the total amount of the developer.

The polyvalent base compound of the present invention may be a low molecular compound or a high molecular compound. Here, the low molecular compound represents, for example, a compound having a molecular weight of 500 or less, and the high molecular compound represents, for example, a compound having a molecular weight exceeding 500 or a compound obtained by polymerization of a monomer.
When the basic compound of the present invention is a polymer compound, the basic functional group may be contained in either the main chain or the side chain of the polymer compound, as will be described later.

In one embodiment of the present invention, the polybasic compound preferably has three or more basic functional groups.
As a basic functional group which a polyvalent base compound has, the amino group which may be substituted, the ammonio group which may be substituted, etc. are mentioned, for example.
In the present invention, the “optionally substituted amino group” is a concept including a primary amino group, a secondary amino group, and a tertiary amino group, such as a pyrrolidino group, a piperazino group, a hexahydrotria. The amino group also includes a cyclic secondary amino group such as a dino group and a tertiary amino group as a partial structure constituting a nitrogen-containing aromatic ring such as pyrazine. Hereinafter, the amino group which may be substituted is simply referred to as “amino group”.

In the present invention, the “optionally substituted ammonio group” represents a group containing a nitrogen atom represented by the following formula, and includes a primary ammonio group, a secondary ammonio group, a tertiary ammonio group, and a quaternary ammonio group. It is a concept that includes a class ammonio group. Ammonio groups also include those having a positive charge on the nitrogen atom of the nitrogen-containing aromatic ring. For example, a quaternary ammonio group as a partial structure constituting a nitrogen-containing aromatic ring such as pyridinium is also included in the ammonio group. Hereinafter, an ammonio group which may be substituted is simply referred to as an “ammonio group”.

In one aspect of the present invention, the polyvalent base compound of the present invention preferably has at least one selected from a tertiary amino group and a quaternary ammonio group as the basic functional group, More preferably, it contains a quaternary ammonio group.

In another embodiment of the present invention, the polybasic compound of the present invention is preferably a low molecular compound having 2 or 3 ammonio groups.

The polybasic compound of the present invention will be described below.
First, a polybasic compound having an ammonio group will be described.
In the present invention, the ammonio group represents a group containing a nitrogen atom represented by the following formula, as described above, and includes a primary ammonio group, a secondary ammonio group, a tertiary ammonio group, and a quaternary ammonio group. It is a concept that includes. In addition, the ammonio group includes those having a positive charge on the nitrogen atom of the nitrogen-containing aromatic ring. For example, a quaternary ammonio group as a partial structure constituting a nitrogen-containing aromatic ring such as pyridinium is also included in the ammonio group. It is.

When the polyvalent base compound of the present invention has an ammonio group, it is preferably in the form of an ammonium salt compound.
The anion (anion) contained in the ammonium salt compound (ammonium salt structure) may be any as long as the basicity is maintained as the developer composition, and may be a monovalent ion. Multivalent ions may be used.

For example, monovalent anions include hydroxy anions, sulfonate anions, formate anions, carboxylate anions, sulfinate anions, boron anions, halide ions, phenol anions, alkoxy anions, hydroxide ions, and the like. Examples of the divalent anion include oxalate ion, phthalate ion, maleate ion, fumarate ion, tartaric acid ion, malate ion, lactate ion, sulfate ion, diglycolate ion, and 2,5-flange. Examples thereof include carboxylate ions.

More specifically, monovalent anions include OH ⁻ , Cl ⁻ , Br ⁻ , I ⁻ , AlCl ₄ ⁻ , Al ₂ Cl ₇ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ⁻ , NO ₃ ^−. , CH ₃ COO ⁻ , CF ₃ COO ⁻ , CH ₃ SO ₃ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ NbF ₆ ⁻ , TaF ₆ ⁻ , F (HF) _n ⁻ , (CN) ₂ N ⁻ , C ₄ F ₉ SO ₃ ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , C ₃ F ₇ COO ⁻ , (CF ₃ SO ₂ ) (CF ₃ CO) N ⁻ , C ₉ H ₁₉ COO ⁻ , (CH ₃ ) ₂ PO ₄ ⁻ , (C ₂ H ₅ ) ₂ PO ₄ ⁻ , C ₂ H ₅ OSO ₃ ⁻ , C ₆ H ₁₃ OSO ₃ ⁻ , C ₈ H ₁₇ OSO ₃ ⁻ , CH ₃ (OC ₂ H ₄ ) ₂ OSO ₃ ⁻ , C ₆ H ₄ (CH ₃ ) SO ₃ ⁻ , (C ₂ F ₅ ) ₃ PF ₃ ⁻ , CH ₃ CH (OH) COO ⁻ , B (C ₆ F ₅ ) ₄ ⁻ , FSO ₃ ⁻ , C ₆ H ₅ O ⁻ , (CF ₃ ) ₂ CHO ⁻ , (CF ₃ ) ₃ CHO ⁻ , C ₆ H ₃ (CH ₃ ) ₂ O ⁻ , C ₂ H ₅ OC ₆ H ₄ COO- ^{and the} like.

Among them, OH ⁻ , sulfonate anion, carboxylate anion, bis (alkylsulfonyl) amide anion, tris (alkylsulfonyl) methide anion, BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ^{− and the} like are preferable, and OH is more preferable. ^- .

Below, the example of the cation contained in the ammonium salt structure which concerns on the polyvalent base compound of this invention is illustrated.

Below, the specific example of the anion contained in an ammonium salt structure is illustrated.

Below, the specific example of an ammonium salt structure is illustrated.

Preferred embodiments of the ammonium salt compound include the onium salt compound represented by the formula (1-1), the onium salt compound represented by the formula (1-2), and the formula, from the viewpoint that the effects of the present invention are more excellent. And at least one selected from the group consisting of ammonium salt compounds represented by (1-3).

The onium salt compound represented by the formula (1-1) may be used alone or in combination of two or more. Further, the onium salt compound represented by the formula (1-2) may be used alone or in combination of two or more. Further, the ammonium salt compound represented by the formula (1-3) may be used alone or in combination of two or more. 2 selected from an onium salt compound represented by the formula (1-1), an onium salt compound represented by the formula (1-2), and an ammonium salt compound represented by the formula (1-3). More than one species may be used in combination.

In formula (1-1), each R ₁ independently represents a hydrogen atom, an aliphatic hydrocarbon group that may contain a heteroatom, an aromatic hydrocarbon group that may contain a heteroatom, or these Represents a group in which two or more are combined. However, at least one R ₁ is an aliphatic hydrocarbon group or an aromatic hydrocarbon group containing an ammonio group or an amino group.

The aliphatic hydrocarbon group may be linear, branched or cyclic. Further, the number of carbon atoms contained in the aliphatic hydrocarbon group is not particularly limited, but is preferably 1 to 15 and more preferably 1 to 5 in terms of more excellent effects of the present invention.
Examples of the aliphatic hydrocarbon group include an alkyl group, a cycloalkyl group, an alkene group, an alkyne group, or a group obtained by combining two or more of these.

The aliphatic hydrocarbon group may contain a hetero atom. That is, it may be a heteroatom-containing hydrocarbon group. The type of hetero atom contained is not particularly limited, and examples thereof include a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a selenium atom, and a tellurium atom. For _{_{example, -Y 1 H, -Y 1 -}} , - N (R a) -, - C (= Y 2) -, - CON (R b) -, - C (= Y 3) Y 4 -, - SO _t— , —SO ₂ N (R _c ) —, a halogen atom, or a combination of two or more of these is included.

Y ₁ to Y ₄ are each independently selected from the group consisting of an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom. Of these, an oxygen atom and a sulfur atom are preferred because they are easier to handle.
R _a , R _b , and R _c are each independently selected from a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.
t represents an integer of 1 to 3.

The number of carbon atoms contained in the aromatic hydrocarbon group is not particularly limited, but 6 to 20 is preferable and 6 to 10 is more preferable in terms of more excellent effects of the present invention.
Examples of the aromatic hydrocarbon group include a phenyl group and a naphthyl group.
The aromatic hydrocarbon group may contain a hetero atom. The aspect in which a hetero atom is contained is as described above. In addition, when a hetero atom is contained in an aromatic hydrocarbon group, you may comprise an aromatic heterocyclic group.

As a preferred embodiment of R ₁ , an alkyl group which may contain a hetero atom, an alkene group which may contain a hetero atom, or a cycloalkyl which may contain a hetero atom in that the effect of the present invention is more excellent. Group, and an aryl group which may contain a hetero atom.

A plurality of R ₁ may be bonded to each other to form a ring. The type of ring formed is not particularly limited, and examples thereof include a 5- to 6-membered ring structure.

In formula (1-2), each R ₂ independently represents a hydrogen atom, an aliphatic hydrocarbon group that may contain a heteroatom, an aromatic hydrocarbon group that may contain a heteroatom, or these Represents a group in which two or more are combined. R ₃ represents a hydrogen atom, an aliphatic hydrocarbon group that may contain a hetero atom, an aromatic hydrocarbon group that may contain a hetero atom, or a group in which two or more of these are combined. However, at least one of R ₂ and R ₃ is an aliphatic hydrocarbon group or an aromatic hydrocarbon group containing an ammonio group or an amino group. Specific examples of each group are the same as the specific examples given for R ₁ in the general formula (1-1).

A plurality selected from R ₂ and R ₃ may be bonded to each other to form a ring. The type of ring formed is not particularly limited, and examples thereof include a 5- to 6-membered ring structure. In one embodiment of the present invention, an imidazolium ring represented by the formula (11) is preferable.

In formula (11), the definition of R ₂ is as described above. Rv each independently represents a hydrogen atom or an alkyl group. A plurality of Rv may be bonded to each other to form a ring.

X ⁻ represents a monovalent anion. The definition of monovalent anion is as described above.

The definition of X ⁻ in the formula (1-3) is as described above. In formula (1-3), two X ⁻ are included.

R ₄ is independently a hydrogen atom, an aliphatic hydrocarbon group that may contain a hetero atom, an aromatic hydrocarbon group that may contain a hetero atom, or a group in which two or more of these are combined. To express.

L represents a divalent linking group. As the divalent linking group, a substituted or unsubstituted divalent aliphatic hydrocarbon group (preferably having 1 to 8 carbon atoms, for example, an alkylene group such as a methylene group, an ethylene group, or a propylene group), substituted or unsubstituted A divalent aromatic hydrocarbon group (preferably having 6 to 12 carbon atoms, such as a phenylene group), —O—, —S—, —SO ₂ —, —N (R) — (R: alkyl group), Examples include —CO—, —NH—, —COO—, —CONH—, or a group in which two or more of these are combined (for example, an alkyleneoxy group, an alkyleneoxycarbonyl group, an alkylenecarbonyloxy group, and the like).

Among these, a divalent aliphatic hydrocarbon group or a divalent aromatic hydrocarbon group is preferable in that the effect of the present invention is more excellent.

Further, as another preferred embodiment of the ammonium salt compound, a polymer having an ammonium salt is mentioned in that the effect of the present invention is more excellent. By a polymer having an ammonium salt is intended a polymer having an ammonium salt structure in the side chain or main chain. In particular, a polymer having a repeating unit having an ammonium salt structure is preferable.

The definition of the ammonium salt structure is as described above, and the definitions of cation and anion are also synonymous.

A preferred embodiment of the polymer having an ammonium salt includes a polymer having a repeating unit represented by the formula (5-1) in that the effect of the present invention is more excellent.

In formula (5-1), R _p represents a hydrogen atom or an alkyl group. The number of carbon atoms contained in the alkyl group is not particularly limited, but is preferably 1 to 20 and more preferably 1 to 10 in terms of more excellent effects of the present invention.

L _p represents a divalent linking group. The definition of the divalent linking group represented by L _p is the same as the definition of L represented by the above formula (1-2).

Among these, from the viewpoint that the effects of the present invention are more excellent, L _a is an alkylene group, an arylene group, —COO—, or a group combining two or more of these (—arylene group—alkylene group—, —COO—). Alkylene group- and the like are preferable, and an alkylene group is more preferable.

A _p represents a residue obtained by removing one hydrogen atom from an ammonium salt represented by any one of formula (1-1), formula (1-2), and formula (1-3). The residue refers to a group having a structure in which one hydrogen atom is extracted from any position in the structural formula showing an ammonium salt and can be bonded to L _p . Usually, one of the hydrogen atoms in R is withdrawn and becomes a group having a structure capable of bonding to the above L _p .
The definition of each group in Formula (1-1), Formula (1-2), and Formula (1-3) is as described above.

The content of the repeating unit represented by the above formula (5-1) in the polymer is not particularly limited, but is 30 to 100 mol% with respect to all the repeating units in the polymer in that the effect of the present invention is more excellent. Is preferable, and 50 to 100 mol% is more preferable.

The weight average molecular weight of the polymer is not particularly limited, but is preferably from 1000 to 30000, more preferably from 1000 to 10,000, from the viewpoint that the effect of the present invention is more excellent.

A preferred embodiment of the repeating unit represented by the formula (5-1) is a repeating unit represented by the formula (5-2).

In formula (5-2), the definitions of R, R _p , L _p and X ⁻ are as described above.

Furthermore, preferred embodiments of the repeating unit represented by the formula (5-2) include repeating units represented by the formulas (5-3) to (5-5).

In formula (5-3), the definitions of R, R _p and X ⁻ are as described above.

In formula (5-4), the definitions of R, R _p , and X ⁻ are as described above.

A represents —O—, —NH—, or —NR—. The definition of R is the same as the definition of R in the above formula (1-1).

B represents an alkylene group.

In formula (5-5), the definitions of R, R _p , and X ⁻ are as described above.

Specific examples of the repeating unit represented by formula (5-2) are shown below.

Next, the polybasic compound having an amino group will be described.
Examples of the polyvalent base compound having two or more amino groups include a compound represented by the following general formula (6).

In the general formula (6), R ⁴ and R ⁵ are each independently a hydrogen atom, a hydroxyl group, a formyl group, an alkoxy group, an alkoxycarbonyl group, a chain hydrocarbon group having 1 to 30 carbon atoms, or a carbon number of 3 An alicyclic hydrocarbon group having ˜30, an aromatic hydrocarbon group having 6 to 14 carbon atoms, or a group formed by combining two or more of these groups. R ⁶ represents an n-valent chain hydrocarbon group having 1 to 30 carbon atoms, an n-valent alicyclic hydrocarbon group having 3 to 30 carbon atoms, an n-valent aromatic hydrocarbon group having 6 to 14 carbon atoms, or It is an n-valent group formed by combining two or more of these groups. n is an integer of 2 or more. A plurality of R ⁴ and R ⁵ may be the same or different. Further, any two of R ⁴ to R ⁶ may be bonded to form a ring structure with the nitrogen atom to which each is bonded.

Examples of the chain hydrocarbon group having 1 to 30 carbon atoms represented by R ⁴ and R ⁵ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and 2-methylpropyl. Group, 1-methylpropyl group, t-butyl group and the like.

Examples of the alicyclic hydrocarbon group having 3 to 30 carbon atoms represented by R ⁴ and R ⁶ include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and a norbornyl group.

Examples of the alkyl moiety in the alkoxy group and alkoxycarbonyl group represented by R ⁴ and R ⁵ include, for example, a linear or branched alkyl group having 1 to 30 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms. Specific examples include the same groups as the specific examples of the chain hydrocarbon group and the alicyclic hydrocarbon group.

Examples of the aromatic hydrocarbon group having 6 to 14 carbon atoms represented by R ⁴ and R ⁶ include a phenyl group, a tolyl group, and a naphthyl group.

Examples of the group formed by combining two or more of these groups represented by R ⁴ and R ⁵ include aralkyl groups having 6 to 12 carbon atoms such as benzyl, phenethyl, naphthylmethyl, and naphthylethyl groups. Can be mentioned.

Examples of the n-valent chain hydrocarbon group having 1 to 30 carbon atoms represented by R ⁶ include groups exemplified as the chain hydrocarbon group having 1 to 30 carbon atoms represented by R ⁴ and R ^5. And a group obtained by removing (n-1) hydrogen atoms from the same group.

Examples of the alicyclic hydrocarbon group having 3 to 30 carbon atoms represented by R ⁶ are the same as those exemplified as the alicyclic hydrocarbon group having 3 to 30 carbon atoms represented by R ⁴ and R ⁵ . And a group obtained by removing (n-1) hydrogen atoms from the group.

Examples of the aromatic hydrocarbon group having 6 to 14 carbon atoms represented by R ⁶ are the same as those exemplified as the aromatic hydrocarbon group having 6 to 14 carbon atoms represented by R ⁴ and R ⁵ . And a group obtained by removing (n-1) hydrogen atoms from the group.

Examples of the group formed by combining two or more of these groups represented by R ⁶ are the same as those exemplified as the group formed by combining two or more of these groups represented by R ⁴ and R ⁵ . And a group obtained by removing (n-1) hydrogen atoms from the group.

The groups represented by R ⁴ to R ⁶ may be substituted. Specific examples of the substituent include a methyl group, an ethyl group, a propyl group, an n-butyl group, a t-butyl group, a hydroxyl group, a carboxy group, a halogen atom, and an alkoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. Moreover, as an alkoxy group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. are mentioned, for example.

Examples of the compound represented by the above formula (6) include (cyclo) alkylamine compounds, nitrogen-containing heterocyclic compounds, amide group-containing compounds, urea compounds and the like.

Examples of (cyclo) alkylamine compounds include compounds having two nitrogen atoms, compounds having three or more nitrogen atoms, and the like.

Examples of the (cyclo) alkylamine compound having two nitrogen atoms include ethylenediamine, tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, and 4,4 ′. -Diaminobenzophenone, 4,4'-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 1,4-bis [ 1- (4-aminophenyl) -1-methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene, bis (2-dimethylaminoethyl) ether, bis ( 2-diethylaminoethyl) ether, 1- (2-hydroxyethyl) 2-imidazolidinone, 2-quinoxalinium linoleic, N, N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine, and the like.

Examples of the (cyclo) alkylamine compound having 3 or more nitrogen atoms include polymers such as polyethyleneimine, polyallylamine and 2-dimethylaminoethylacrylamide.

Examples of nitrogen-containing heterocyclic compounds include nitrogen-containing aromatic heterocyclic compounds and nitrogen-containing aliphatic heterocyclic compounds.

Examples of the nitrogen-containing aromatic heterocyclic compound include imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, 2-phenylbenzimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2. -Imidazoles such as methyl-1H-imidazole, pyrazine, pyrazole, pyridazine, quinazoline, purine and the like.

Examples of the nitrogen-containing aliphatic heterocyclic compound include piperazines such as piperazine and 1- (2-hydroxyethyl) piperazine; proline, 1,4-diazabicyclo [2.2.2] octane and the like.

Examples of urea compounds include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri-n-butylthiourea, etc. Is mentioned.

Another preferred embodiment of the polyvalent base compound of the present invention is a compound represented by the formula (3) in that the effect of the present invention is more excellent.

In Formula (3), A represents a single bond or an n-valent organic group.
Specific examples of A include a single bond, a group represented by the following formula (1A), a group represented by the following formula (1B),

—NH—, —NR _W —, —O—, —S—, carbonyl group, alkylene group, alkenylene group, alkynylene group, cycloalkylene group, aromatic group, heterocyclic group, and combinations of two or more thereof A preferred example is an n-valent organic group consisting of a group. Here, in the above formulas, R _W represents an organic group, preferably an alkyl group, an alkylcarbonyl group, an alkylsulfonyl group. Further, in the above combination, heteroatoms are not linked to each other.

Of these, an aliphatic hydrocarbon group (an alkylene group, an alkenylene group, an alkynylene group, a cycloalkylene group), a group represented by the above formula (1B), and —NH— and —NR _W — are preferable.

Here, the alkylene group, alkenylene group, and alkynylene group preferably have 1 to 40 carbon atoms, more preferably 1 to 20 carbon atoms, and still more preferably 2 to 12 carbon atoms. The alkylene group may be linear or branched and may have a substituent. Here, the cycloalkylene group preferably has 3 to 40 carbon atoms, more preferably 3 to 20 carbon atoms, and still more preferably 5 to 12 carbon atoms. The cycloalkylene group may be monocyclic or polycyclic, and may have a substituent on the ring.

The aromatic group may be monocyclic or polycyclic, and includes non-benzene aromatic groups. Monocyclic aromatic groups include benzene, pyrrole, furan, thiophene, and indole residues. Polycyclic aromatic groups include naphthalene, anthracene, tetracene, and benzofuran. Examples include benzothiophene residues and the like. The aromatic group may have a substituent.

The n-valent organic group may have a substituent, and the kind thereof is not particularly limited, but an alkyl group, an alkoxy group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkyloxycarbonyl group, an alkenyl group, an alkenyloxy group Alkenylcarbonyl group, alkenylcarbonyloxy group, alkenyloxycarbonyl group, alkynyl group, alkynyleneoxy group, alkynylenecarbonyl group, alkynylenecarbonyloxy group, alkynyleneoxycarbonyl group, aralkyl group, aralkyloxy group, aralkylcarbonyl group Aralkylcarbonyloxy group, aralkyloxycarbonyl group, hydroxyl group, amide group, carboxyl group, cyano group, fluorine atom and the like can be mentioned as examples.

B represents a single bond, an alkylene group, a cycloalkylene group, or an aromatic group, and the alkylene group, the cycloalkylene group, and the aromatic group may have a substituent. Here, the explanation of the alkylene group, cycloalkylene group, and aromatic group is the same as described above.

However, A and B are not both single bonds.

R _z each independently represents a hydrogen atom, an aliphatic hydrocarbon group that may contain a heteroatom, or an aromatic hydrocarbon group that may contain a heteroatom.

Examples of the aliphatic hydrocarbon group include an alkyl group, an alkenyl group, and an alkynyl group. The number of carbon atoms contained in the aliphatic hydrocarbon group is not particularly limited, but 1 to 20 is preferable and 1 to 10 is more preferable in terms of more excellent effects of the present invention.

Examples of the aromatic hydrocarbon group include a phenyl group and a naphthyl group.

The aliphatic hydrocarbon group and the aromatic hydrocarbon group may contain a hetero atom. The definition and preferred embodiment of the heteroatom are the same as the definition of the heteroatom described in the above formula (1-1).

In addition, aliphatic hydrocarbon groups and aromatic hydrocarbon groups include substituents (eg, hydroxyl groups, cyano groups, amino groups, pyrrolidino groups, piperidino groups, morpholino groups, oxo groups and other functional groups, alkoxy groups, halogen atoms, Atoms) may be included.

N represents an integer of 2 to 8, preferably an integer of 3 to 8.

In addition, it is preferable that the compound represented by the said Formula (3) has three or more nitrogen atoms. In this embodiment, when n is 2, A contains at least one nitrogen atom. “A includes a nitrogen atom” includes, for example, at least one selected from the group consisting of the group represented by the above formula (1B), —NH—, and —NR _W —.
Below, the compound represented by Formula (3) is illustrated.

Another preferred embodiment of the polybasic compound of the present invention is preferably a polymer having an amino group in that the effect of the present invention is more excellent.

The amino group may be contained in either the main chain or the side chain of the polymer.

Specific examples of the side chain when the amino group is contained in a part of the side chain are shown below. In addition, * represents the connection part with a polymer and / or an oligomer residue.

Examples of the polymer having an amino group include polyallylamine, polyethyleneimine, polyvinylpyridine, polyvinylimidazole, polypyrimidine, polytriazole, polyquinoline, polyindole, polypurine, polyvinylpyrrolidone, polybenzimidazole and the like.

As a suitable aspect of the polymer which has an amino group, the polymer which has a repeating unit represented by Formula (2) is mentioned.

In formula (2), R ¹ represents a hydrogen atom or an alkyl group. The number of carbon atoms contained in the alkyl group is not particularly limited, but is preferably 1 to 4 and more preferably 1 to 2 in terms of more excellent effects of the present invention.

R ² and R ³ are each independently a hydrogen atom, an alkyl group that may contain a hetero atom, a cycloalkyl group that may contain a hetero atom, or an aromatic group that may contain a hetero atom. Represents.

The number of carbon atoms contained in the alkyl group and cycloalkyl group is not particularly limited, but is preferably 1 to 20, and more preferably 1 to 10.

Examples of the aromatic group include an aromatic hydrocarbon group and an aromatic heterocyclic group.

The above alkyl group, cycloalkyl group and aromatic group may contain a hetero atom. The definition and preferred embodiment of the heteroatom are the same as the definition of the heteroatom described in the above formula (1-1).

In addition, the alkyl group, cycloalkyl group, and aromatic group include substituents (eg, hydroxyl group, cyano group, amino group, pyrrolidino group, piperidino group, morpholino group, oxo group functional group, alkoxy group, halogen Atoms) may be included.

L _a represents a divalent linking group. Definition of the divalent linking group represented by L _a is the same definition of L represented by the aforementioned formula (1-2).

Incidentally, the group represented by the above R ¹ ~ R ^3, and, in the divalent linking group represented by L _a, substituent group (e.g., hydroxyl, etc.) may be further substituted.

Below, the repeating unit represented by Formula (2) is illustrated.

The content of the repeating unit represented by the above formula (2) in the polymer is not particularly limited, but is preferably 40 to 100 mol% with respect to all the repeating units in the polymer in terms of more excellent effects of the present invention. 70 to 100 mol% is more preferable.

In the polymer, other repeating units other than the repeating unit represented by the formula (2) may be contained.

The weight average molecular weight of the polymer having an amino group is not particularly limited, but is preferably from 1000 to 30000, more preferably from 1000 to 10,000, from the viewpoint that the effect of the present invention is more excellent.

In one embodiment of the present invention, the polyvalent base compound is preferably a compound that is easily dissolved in water. Specifically, it is preferably a compound capable of preparing an aqueous solution having a base normality at 23 ° C. of 0.1 N or more, and more preferably a compound capable of preparing an aqueous solution of 0.2 N or more. By using a compound capable of preparing an aqueous solution of 0.1 N or more, it becomes easy to prepare a developer having a base concentration necessary for dissolving the resist.

The addition amount of the polybasic compound of the present invention to the aqueous developer is not particularly limited, but is 0.1 to 10% by mass with respect to the total amount of the developer in that the effect of the present invention is more excellent. Preferably, it is 1 to 10% by mass, more preferably 1 to 5% by mass.

In the present invention, as the polyvalent base compound of the present invention, one type of compound may be used alone, or two or more types of compounds having different chemical structures may be used.
The aqueous developer includes other basic compounds that are not polyvalent, such as non-polyvalent quaternary ammonium salts represented by tetramethylammonium hydroxide, inorganic alkalis, primary amines, secondary amines, 3 A secondary amine, alcohol amine, cyclic amine or the like may be further added, and other optional components such as a surfactant and alcohols may be added. Specific examples and usage amounts of the surfactant are the same as those of the organic developer described later.
The alkali concentration of the aqueous developer is usually from 0.1 to 20% by mass, and the pH value of the aqueous developer is usually from 10.0 to 15.0.

・ Organic solvent development process (second development process)
In the organic solvent development step, a developer containing a soluble solvent (hereinafter also referred to as an organic developer) is used as a developer.
This organic developer contains an organic solvent as a main component. The main component means that the content of the organic solvent is more than 50% by mass with respect to the total amount of the developer.

The organic solvent contained in the organic developer is not particularly limited, and examples thereof include polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents. Can be mentioned. Moreover, these mixed solvents may be sufficient.

Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone (methyl amyl ketone), 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, Examples include cyclohexanone, methylcyclohexanone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone, acetonylacetone, ionone, diacetylalcohol, acetylcarbinol, acetophenone, methylnaphthylketone, isophorone, and propylene carbonate.

Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl. Examples include ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, and propyl lactate. be able to.

Examples of the alcohol solvents include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, n-heptyl alcohol, Alcohol solvents such as n-octyl alcohol and n-decanol, glycol solvents such as ethylene glycol, diethylene glycol and triethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl Ether, diethylene glycol monomethyl ether, triethylene glycol monoethyl ether, methoxymethyl Glycol ether solvents such as butanol.

Examples of the ether solvent include dioxane, tetrahydrofuran and the like in addition to the glycol ether solvent.

Examples of amide solvents include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolidinone and the like. Can be used.

Examples of the hydrocarbon solvent include aromatic hydrocarbon solvents such as toluene and xylene, and aliphatic hydrocarbon solvents such as pentane, hexane, octane and decane.

In particular, the organic developer is preferably a developer containing at least one organic solvent selected from the group consisting of ketone solvents and ester solvents, and in particular, butyl acetate or ketone as the ester solvent. A developer containing methyl amyl ketone (2-heptanone) as a system solvent is preferred.

A plurality of organic solvents may be mixed, or may be used by mixing with other solvents or water. However, in order to fully exhibit the effects of the present invention, the water content of the developer as a whole is preferably less than 10% by mass, and more preferably substantially free of moisture.

That is, the amount of the organic solvent used relative to the organic developer is preferably 90% by mass or more and 100% by mass or less, and more preferably 95% by mass or more and 100% by mass or less with respect to the total amount of the developer. .

The vapor pressure of the organic developer is preferably 5 kPa or less, more preferably 3 kPa or less, and particularly preferably 2 kPa or less at 20 ° C. By setting the vapor pressure of the organic developer to 5 kPa or less, evaporation of the developer on the substrate or in the developing cup is suppressed, and the temperature uniformity in the wafer surface is improved. As a result, the dimensions in the wafer surface are uniform. Sexuality improves.

An appropriate amount of a surfactant can be added to the organic developer as required.
The surfactant is not particularly limited, and for example, ionic or nonionic fluorine-based and / or silicon-based surfactants can be used. Examples of these fluorine and / or silicon surfactants include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP-A-63-34540, JP-A-7-230165, JP-A-8-62834, JP-A-9-54432, JP-A-9-5988, US Pat. No. 5,405,720, The surfactants described in the specifications of US Pat. Preferably, it is a nonionic surfactant. Although it does not specifically limit as a nonionic surfactant, It is still more preferable to use a fluorochemical surfactant or a silicon-type surfactant.

The amount of the surfactant used is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass with respect to the total amount of the developer.

Hereinafter, other processes will be described.

[Film forming process]
The actinic ray-sensitive or radiation-sensitive resin composition can be applied to the substrate by a generally known method. For example, an actinic ray-sensitive or radiation-sensitive resin composition may be formed by applying an actinic ray-sensitive or radiation-sensitive resin composition on the substrate at the center of the wafer and then rotating the substrate with a spinner. The actinic ray-sensitive or radiation-sensitive resin composition may be applied while rotating to form an actinic ray-sensitive or radiation-sensitive film.

[Exposure process]
Although there is no restriction | limiting in the light source wavelength used for the exposure method of this invention, Infrared light, visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light, X-rays, an electron beam, etc. can be mentioned, Preferably it is 250 nm or less. More preferably 220 nm or less, particularly preferably far ultraviolet light having a wavelength of 1 to 200 nm, specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), X-ray, EUV (13 nm), electron beam, etc., KrF excimer laser, ArF excimer laser, EUV or electron beam are preferable, and ArF excimer laser is more preferable.

Also, an immersion exposure method can be applied in the exposure process of the present invention. The immersion exposure method can be combined with a super-resolution technique such as a phase shift method or a modified illumination method.

When performing immersion exposure, (1) after forming the film on the substrate, before the exposure step and / or (2) after exposing the film via the immersion liquid, Prior to the heating step, a step of washing the surface of the membrane with an aqueous chemical may be performed.

The immersion liquid is preferably a liquid that is transparent to the exposure wavelength and has a refractive index temperature coefficient as small as possible so as to minimize distortion of the optical image projected onto the film. In the case of an ArF excimer laser (wavelength: 193 nm), it is preferable to use water from the viewpoints of availability and ease of handling in addition to the above-described viewpoints.

When water is used, an additive (liquid) that decreases the surface tension of water and increases the surface activity may be added in a small proportion. This additive is preferably one that does not dissolve the resist layer on the wafer and can ignore the influence on the optical coating on the lower surface of the lens element.
As such an additive, for example, an aliphatic alcohol having a refractive index substantially equal to that of water is preferable, and specific examples include methyl alcohol, ethyl alcohol, isopropyl alcohol and the like. By adding an alcohol having a refractive index substantially equal to that of water, even if the alcohol component in water evaporates and the content concentration changes, an advantage that the change in the refractive index of the entire liquid can be made extremely small can be obtained.

On the other hand, when an opaque substance or impurities whose refractive index is significantly different from that of water are mixed with respect to 193 nm light, the optical image projected on the resist is distorted. Therefore, distilled water is preferable as the water to be used. Further, pure water filtered through an ion exchange filter or the like may be used.
The electrical resistance of water used as the immersion liquid is preferably 18.3 MQcm or more, the TOC (organic substance concentration) is preferably 20 ppb or less, and deaeration treatment is preferably performed.

Moreover, it is possible to improve lithography performance by increasing the refractive index of the immersion liquid. From such a viewpoint, an additive that increases the refractive index may be added to water, or heavy water (D ₂ O) may be used instead of water.

The receding contact angle of the resist film formed by using the actinic ray-sensitive or radiation-sensitive resin composition in the present invention is 70 ° or more at a temperature of 23 ± 3 ° C. and a humidity of 45 ± 5%, and through the immersion medium. Suitable for exposure, preferably 75 ° or more, more preferably 75 to 85 °.
If the receding contact angle is too small, it cannot be suitably used for exposure through an immersion medium, and the effect of reducing water residue (watermark) defects cannot be sufficiently exhibited. In order to realize a preferable receding contact angle, it is preferable to include the hydrophobic resin (HR) in the actinic ray-sensitive or radiation-sensitive resin composition. Alternatively, the receding contact angle may be improved by forming a coating layer (so-called “topcoat”) of a hydrophobic resin composition on the resist film.

In the immersion exposure process, the immersion head needs to move on the wafer following the movement of the exposure head to scan the wafer at high speed to form the exposure pattern. In this case, the contact angle of the immersion liquid with respect to the resist film is important, and the resist is required to follow the high-speed scanning of the exposure head without remaining droplets.

[Heating process]
In one form, the pattern formation method of this invention may include the heating process.
The pattern formation method of the present invention may include, for example, a preheating (PB) process between the film forming process and the exposure process.
Moreover, the pattern formation method of this invention may include the post-exposure heating (Post Exposure Bake: PEB) process between an exposure process and an alkali image development process in another form.

In addition, when the pattern forming method of the present invention includes an organic solvent developing step, the baking process (first post-baking step) is performed between the alkali developing step and the organic solvent developing step for the purpose of further increasing the deprotection amount of the pattern side wall. ) May be included.

Further, when the pattern forming method of the present invention includes an organic solvent developing step, it may include a heating step (second post-baking step) after the organic solvent developing step.

For example, the heating temperature in each heating step is preferably 70 ° C. to 150 ° C., more preferably 80 ° C. to 130 ° C.
For example, the heating time in each heating step is preferably 30 to 300 seconds, more preferably 30 to 180 seconds, and still more preferably 30 to 90 seconds.
In one embodiment, the pattern forming method of the present invention is such that the heating temperature of the first post-bake between the alkali development step and the organic solvent development step is higher than the heating temperature in the PEB step between the exposure step and the alkali development step. Preferably, it is more preferably 30 ° C. or higher. By making the heating temperature of the first post-baking higher than the heating temperature in the PEB process, an additional polarity conversion reaction due to the acid remaining on the pattern side wall occurs, and the interaction formation with the base in the developer is promoted. be able to.

The heating can be performed by means provided in a normal exposure / developing machine, and may be performed using a hot plate or the like.

[Rinse process]
In one form, the pattern formation method of this invention may include the rinse process wash | cleaned using a rinse liquid after an alkali image development process and / or after an organic-solvent image development process.

As a rinsing solution in the rinsing treatment performed after alkali development, pure water can be used, and an appropriate amount of a surfactant can be added.
In addition, after the developing process or the rinsing process, a process of removing the developing solution or the rinsing liquid adhering to the pattern with a supercritical fluid can be performed.

The rinsing liquid in the rinsing treatment performed after organic solvent development is not particularly limited as long as the resist pattern is not dissolved, and a solution containing a general organic solvent can be used. As the rinse liquid, a rinse liquid containing at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents is used. It is preferable.

Specific examples of the hydrocarbon solvent, ketone solvent, ester solvent, alcohol solvent, amide solvent and ether solvent are the same as those described in the developer containing an organic solvent.

More preferably, it contains at least one organic solvent selected from the group consisting of ketone solvents, ester solvents, alcohol solvents, and amide solvents after the step of developing using a developer containing an organic solvent. A step of washing with a rinsing liquid is performed, more preferably, a step of washing with a rinsing liquid containing an alcohol solvent or an ester solvent is carried out, and particularly preferably, a rinsing liquid containing a monohydric alcohol is used. And, most preferably, the step of cleaning with a rinse solution containing a monohydric alcohol having 5 or more carbon atoms is performed.

Here, examples of the monohydric alcohol used in the rinsing step include linear, branched, and cyclic monohydric alcohols. Specific examples include 1-hexanol, 2-hexanol, and 4-methyl-2-pen. Tanol, 1-pentanol, 3-methyl-1-butanol and the like can be used.
A plurality of the above components may be mixed, or may be used by mixing with an organic solvent other than the above.

The water content in the rinse liquid is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 3% by mass or less. By setting the water content to 10% by mass or less, good development characteristics can be obtained.

The vapor pressure of the rinsing solution used after the step of developing with a developer containing an organic solvent is preferably 0.05 kPa or more and 5 kPa or less, more preferably 0.1 kPa or more and 5 kPa or less at 20 ° C. 12 kPa or more and 3 kPa or less are the most preferable. By setting the vapor pressure of the rinse liquid to 0.05 kPa or more and 5 kPa or less, the temperature uniformity in the wafer surface is improved, and further, the swelling due to the penetration of the rinse solution is suppressed, and the dimensional uniformity in the wafer surface. Improves.

An appropriate amount of a surfactant can be added to the rinse solution.
In the rinsing step, the wafer that has been developed using the developer containing the organic solvent is cleaned using the rinse solution containing the organic solvent. The cleaning method is not particularly limited. For example, a method of continuing to discharge the rinse liquid onto the substrate rotating at a constant speed (rotary coating method), or immersing the substrate in a tank filled with the rinse liquid for a certain period of time. A method (dip method), a method of spraying a rinsing liquid onto the substrate surface (spray method), etc. can be applied. Among these, a cleaning process is performed by a spin coating method, and after cleaning, the substrate is rotated at a speed of 2000 rpm to 4000 rpm. It is preferable to rotate and remove the rinse liquid from the substrate. It is also preferable to include a heating step (Post Bake) after the rinsing step. The developing solution and the rinsing solution remaining between the patterns and inside the patterns are removed by baking. The heating step after the rinsing step is usually performed at 40 to 160 ° C., preferably 70 to 95 ° C., usually 10 seconds to 3 minutes, preferably 30 seconds to 90 seconds.

The organic developer, alkali developer, and / or rinse solution used in the present invention preferably have few impurities such as various fine particles and metal elements. In order to obtain such chemicals with few impurities, these chemicals are manufactured in a clean room, and filtered with various filters such as Teflon (registered trademark) filters, polyolefin filters, ion exchange filters, etc. It is preferable to reduce impurities. As for the metal element, the metal element concentrations of Na, K, Ca, Fe, Cu, Mg, Mn, Li, Al, Cr, Ni, and Zn are all preferably 10 ppm or less, and preferably 5 ppm or less. More preferred.

The storage container for the developer and the rinsing liquid is not particularly limited, and containers such as polyethylene resin, polypropylene resin, and polyethylene-polypropylene resin that are used for electronic materials can be used as appropriate. In order to reduce impurities eluted from the container, it is also preferable to select a container having a small amount of components eluted from the inner wall of the container into the chemical solution. As such a container, a container whose inner wall is made of perfluoro resin (for example, FluoroPure PFA composite drum (wetted inner surface; PFA resin lining) manufactured by Entegris), steel drum can manufactured by JFE (wetted inner surface; zinc phosphate coating) ) And the like.

The present invention also relates to an electronic device manufacturing method including the pattern forming method of the present invention described above, and an electronic device manufactured by this manufacturing method.
The electronic device of the present invention is suitably mounted on electrical and electronic equipment (home appliances, OA / media related equipment, optical equipment, communication equipment, etc.).

<Actinic ray-sensitive or radiation-sensitive resin composition>
Hereinafter, the actinic ray-sensitive or radiation-sensitive resin composition that can be used in the pattern forming method of the present invention will be described.

Examples of the actinic ray-sensitive or radiation-sensitive resin composition include known positive photoresists for g-line and i-line, specifically, photo-generated carboxylic acid by photoreaction of so-called naphthoquinonediazide group. A resist can be applied as appropriate. More specifically, "New development of photoresist material development, supervised by CMC Publishing: Mitsue Ueda's" Resistors introduced in Chapter 4 Conventional Photoresist "" "Semiconductor Integrated Circuit Resist Material Handbook, Realize Co., Ltd." The diazonaphthoquinone (DNQ) -novolak resin-based positive photoresist described in “Chapter 4 g / i-ray resist material” can be used, but is not limited thereto.

The actinic ray-sensitive or radiation-sensitive resin composition includes an actinic ray containing a resin that decomposes by the action of an acid to produce an acidic functional group, and a compound that generates an acid upon irradiation with an actinic ray or radiation. And a radiation-sensitive resin composition.

The actinic ray-sensitive or radiation-sensitive resin composition is preferably the actinic ray-sensitive or radiation-sensitive resin composition. The actinic ray-sensitive or radiation-sensitive resin composition is typically a chemically amplified resist composition.

Hereinafter, each component of the actinic ray-sensitive or radiation-sensitive resin composition (hereinafter simply referred to as “the composition of the present invention”) will be described in detail.

[1] Resins that decompose by the action of an acid to generate acidic functional groups Resins that decompose by the action of an acid to generate acidic functional groups include, for example, the main chain or side chain of the resin, or the main chain and side chain Resin (hereinafter also referred to as “acid-decomposable group” or “resin (A)”) having a group (hereinafter also referred to as “acid-decomposable group”) that decomposes by the action of an acid to generate an acidic functional group. Can be mentioned.

The acid-decomposable group preferably has a structure protected with a group capable of decomposing and leaving an acidic functional group by the action of an acid. Preferred polar groups include carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol groups), and sulfonic acid groups.

A preferred group as the acid-decomposable group is a group in which the hydrogen atom of these groups is substituted with a group capable of leaving with an acid.

Examples of the group leaving with an acid include —C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), —C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ), —C (R ₀₁ ) (R ₀₂ ). ) (OR ₃₉ ) and the like.

In the formula, each of R ₃₆ to R ₃₉ independently represents an alkyl group, a cycloalkyl group (monocyclic or polycyclic), an aryl group, an aralkyl group, or an alkenyl group. R ₃₆ and R ₃₇ may be bonded to each other to form a ring.

R ₀₁ and R ₀₂ each independently represents a hydrogen atom, an alkyl group (monocyclic or polycyclic), a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group.

The acid-decomposable group is preferably a cumyl ester group, an enol ester group, an acetal ester group, a tertiary alkyl ester group or the like. More preferably, it is a tertiary alkyl ester group. Further, when the pattern forming method of the present invention is performed by exposure with KrF light or EUV light, or electron beam irradiation, it is also preferable to use an acid-decomposable group in which a phenolic hydroxyl group is protected with an acid leaving group.

The resin (A) preferably has a repeating unit having an acid-decomposable group.
Examples of this repeating unit include the following.

In general formulas (aI) and (aI ′)
Xa ₁ represents a hydrogen atom, an alkyl group, a cyano group, or a halogen atom.

T represents a single bond or a divalent linking group.

Rx ₁ to Rx ₃ each independently represents an alkyl group or a cycloalkyl group. Two of Rx ₁ to Rx ₃ may combine to form a ring structure. The ring structure may contain a hetero atom such as an oxygen atom in the ring.

Examples of the divalent linking group of T include an alkylene group, —COO—Rt— group, —O—Rt— group, phenylene group and the like. In the formula, Rt represents an alkylene group or a cycloalkylene group.

T in the general formula (aI) is preferably a single bond or a —COO—Rt— group, more preferably a —COO—Rt— group, from the viewpoint of insolubilization of the resist in an organic solvent developer. Rt is preferably an alkylene group having 1 to 5 carbon atoms, more preferably a —CH ₂ — group, — (CH ₂ ) ₂ — group, or — (CH ₂ ) ₃ — group.

T in the general formula (aI ′) is preferably a single bond.

The alkyl group of _Xa1 may have a substituent, and examples of the substituent include a hydroxyl group and a halogen atom (preferably a fluorine atom).

The alkyl group for X _a1 preferably has 1 to 4 carbon atoms, and is preferably a methyl group.

X _a1 is preferably a hydrogen atom or a methyl group.

The alkyl group for Rx ₁ , Rx ₂ and Rx ₃ may be linear or branched.

Examples of the cycloalkyl group of Rx ₁ , Rx ₂ and Rx ₃ include polycyclic rings such as a monocyclic cycloalkyl group such as a cyclopentyl group and a cyclohexyl group, a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group and an adamantyl group. Are preferred.

The ring structure formed by combining two of Rx ₁ , Rx ₂ and Rx ₃ includes a monocyclic cycloalkane ring such as cyclopentyl ring and cyclohexyl ring, norbornane ring, tetracyclodecane ring, tetracyclododecane ring, adamantane ring A polycyclic cycloalkyl group such as is preferable. A monocyclic cycloalkane ring having 5 or 6 carbon atoms is particularly preferable.

Rx ₁ , Rx ₂ and Rx ₃ are preferably each independently an alkyl group, more preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

Each of the above groups may have a substituent, and examples of the substituent include an alkyl group (1 to 4 carbon atoms), a cycloalkyl group (3 to 8 carbon atoms), a halogen atom, an alkoxy group (carbon 1 to 4), a carboxyl group, an alkoxycarbonyl group (2 to 6 carbon atoms), and the like, and 8 or less carbon atoms are preferable. Among these, from the viewpoint of further improving the dissolution contrast with respect to a developer containing an organic solvent before and after acid decomposition, a substituent having no hetero atom such as an oxygen atom, a nitrogen atom, or a sulfur atom is more preferable ( For example, it is more preferable that it is not an alkyl group substituted with a hydroxyl group, etc.), a group consisting of only a hydrogen atom and a carbon atom is more preferable, and a linear or branched alkyl group or a cycloalkyl group is particularly preferable. preferable.

Although the specific example of the repeating unit which has an acid-decomposable group is given, it is not limited to these.
In specific examples, Rx represents a hydrogen atom, CH ₃ , CF ₃ , or CH ₂ OH. Rxa and Rxb each represents an alkyl group having 1 to 4 carbon atoms. Xa ₁ represents a hydrogen atom, CH ₃ , CF ₃ , or CH ₂ OH. Z represents a substituent, and when a plurality of Zs are present, the plurality of Zs may be the same as or different from each other. p represents 0 or a positive integer. Specific examples and preferred examples of Z are the same as specific examples and preferred examples of the substituent that each group such as Rx ₁ to Rx ₃ may have.

In the following specific examples, Xa represents a hydrogen atom, an alkyl group, a cyano group, or a halogen atom.

In the following specific examples, Xa ₁ represents a hydrogen atom, CH ₃ , CF ₃ , or CH ₂ OH.

One type of repeating unit having an acid-decomposable group may be used, or two or more types may be used in combination. By using two or more types together, it is possible to adjust depth of focus, exposure latitude, and other various performances.
In the case of using two or more kinds in combination, any acid-decomposable group may be used in combination. For example, (i) a mode in which a repeating unit that decomposes by the action of an acid to generate a carboxyl group and a repeating unit that decomposes by the action of an acid to generate an alcoholic hydroxyl group can be used. And (ii) a combination of two repeating units represented by the following general formula (I) and two repeating units represented by the general formula (II), (iii) a repeating unit represented by the general formula (I) A combination of at least two types is also preferable.

In formulas (I) and (II),
R ₁ and R ₃ are each independently synonymous with Xa ₁ in General Formula (aI) described above, and the preferred embodiments are also the same.
R ₂ , R ₄ , R ₅ and R ₆ each independently represents an alkyl group or a cycloalkyl group.
R represents an atomic group necessary for forming an alicyclic structure together with the carbon atom to which R ₂ is bonded.

The alkyl group in R ₂ may be linear or branched, and may have a substituent.
The cycloalkyl group in R ₂ may be monocyclic or polycyclic and may have a substituent.

R ₂ is preferably an alkyl group, more preferably an alkyl group having 1 to 10 carbon atoms, still more preferably 1 to 5 carbon atoms, and examples thereof include a methyl group and an ethyl group.

R represents an atomic group necessary for forming an alicyclic structure together with a carbon atom. The alicyclic structure formed by R together with the carbon atom is preferably a monocyclic alicyclic structure, and the carbon number thereof is preferably 3 to 7, more preferably 5 or 6.
R ₃ is preferably a hydrogen atom or a methyl group, and more preferably a methyl group.

The alkyl group in R ₄ , R ₅ , and R ₆ may be linear or branched and may have a substituent. As the alkyl group, those having 1 to 4 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group and t-butyl group are preferable.

The cycloalkyl group in R ₄ , R ₅ and R ₆ may be monocyclic or polycyclic and may have a substituent. The cycloalkyl group is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, or a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group or an adamantyl group.

Each of the above groups may further have a substituent.

When two or more repeating units of the general formula (I) are included, the alicyclic structure formed by R together with the carbon atom is a monocyclic alicyclic structure, and the alicyclic structure formed by R together with the carbon atom. It is preferable that both the repeating unit which is a polycyclic alicyclic structure is included. The monocyclic alicyclic structure preferably has 5 to 8 carbon atoms, more preferably 5 or 6 carbon atoms, and particularly preferably 5 carbon atoms. As the polycyclic alicyclic structure, a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group are preferable.

In particular, specific examples of preferable combinations in the case of (ii) and (iii) described above will be shown. In the following formula, each R independently represents a hydrogen atom or a methyl group.

The content of the repeating unit having an acid-decomposable group contained in the resin (A) (when there are a plurality of repeating units having an acid-decomposable group, the total) is based on the total repeating units of the resin (A), It is preferably 15 mol% or more, more preferably 20 mol% or more, further preferably 25 mol% or more, and particularly preferably 40 mol% or more.

Resin (A) may contain a repeating unit having a lactone structure or a sultone structure.

Specific examples of the repeating unit having a group having a lactone structure or a sultone structure are shown below, but the present invention is not limited thereto.

It is also possible to use a repeating unit having two or more lactone structures or sultone structures in combination.

When the resin (A) contains a repeating unit having a lactone structure or a sultone structure, the content of the repeating unit having a lactone structure or a sultone structure is 5 to 60 mol% with respect to all the repeating units in the resin (A). It is preferably 5 to 55 mol%, more preferably 10 to 50 mol%.

Further, the resin (A) may have a repeating unit having a cyclic carbonate structure. Specific examples are given below, but the present invention is not limited thereto.

In the following specific examples, R _A ¹ represents a hydrogen atom or an alkyl group (preferably a methyl group).

The resin (A) may have a repeating unit having a hydroxyl group or a cyano group.
Specific examples of the repeating unit having a hydroxyl group or a cyano group are given below, but the present invention is not limited thereto.

Resin (A) may have a repeating unit having an acid group.

The resin (A) may or may not contain a repeating unit having an acid group, but when it is contained, the content of the repeating unit having an acid group is relative to all the repeating units in the resin (A). It is preferably 25 mol% or less, and more preferably 20 mol% or less. When resin (A) contains the repeating unit which has an acid group, content of the repeating unit which has an acid group in resin (A) is 1 mol% or more normally.

Specific examples of the repeating unit having an acid group are shown below, but the present invention is not limited thereto.
In specific examples, Rx represents H, CH ₃ , CH ₂ OH, or CF ₃ .

The resin (A) further has a repeating unit that has an alicyclic hydrocarbon structure and / or an aromatic ring structure that does not have a polar group (for example, the above acid group, hydroxyl group, and cyano group) and does not exhibit acid decomposability. be able to.

The resin (A) may or may not contain this repeating unit, but when it is contained, it is usually 1 mol% or more and 30 mol% or less, preferably with respect to all repeating units in the resin (A). Is 3 mol% or more and 25 mol% or less.

Specific examples of the repeating unit having an alicyclic hydrocarbon structure having no polar group and not exhibiting acid decomposability are shown below, but the present invention is not limited thereto. In the formula, Ra represents H, CH ₃ , CH ₂ OH, or CF ₃ .

When the composition of the present invention is for ArF exposure, the resin (A) used in the composition of the present invention has substantially no aromatic ring from the viewpoint of transparency to ArF light (specifically, The ratio of the repeating unit having an aromatic group in the resin is preferably 5 mol% or less, more preferably 3 mol% or less, ideally 0 mol%, that is, no aromatic group). The resin (A) preferably has a monocyclic or polycyclic alicyclic hydrocarbon structure.

The form of the resin (A) in the present invention may be any of random type, block type, comb type, and star type. Resin (A) is compoundable by the radical, cation, or anion polymerization of the unsaturated monomer corresponding to each structure, for example. It is also possible to obtain the desired resin by conducting a polymer reaction after polymerization using an unsaturated monomer corresponding to the precursor of each structure.

When the composition of the present invention contains a resin (D) described later, it is preferable that the resin (A) does not contain a fluorine atom and a silicon atom from the viewpoint of compatibility with the resin (D).

The resin (A) used in the composition of the present invention is preferably such that all of the repeating units are composed of (meth) acrylate-based repeating units. In this case, all of the repeating units are methacrylate repeating units, all of the repeating units are acrylate repeating units, or all of the repeating units are methacrylate repeating units and acrylate repeating units. Although it can be used, the acrylate-based repeating unit is preferably 50 mol% or less of the total repeating units.

When the composition of the present invention is irradiated with KrF excimer laser light, electron beam, X-ray, high energy light beam (EUV, etc.) having a wavelength of 50 nm or less, the resin (A) has a repeating unit having an aromatic ring. May be. The repeating unit having an aromatic ring is not particularly limited, and is also exemplified in the above description of each repeating unit, but a styrene unit, a hydroxystyrene unit, a phenyl (meth) acrylate unit, a hydroxyphenyl (meth) acrylate. Examples include units. More specifically, the resin (A) is a resin having a hydroxystyrene-based repeating unit and a hydroxystyrene-based repeating unit protected by an acid-decomposable group, a repeating unit having the aromatic ring, and (meth) Examples thereof include a resin having a repeating unit in which the carboxylic acid moiety of acrylic acid is protected by an acid-decomposable group. In particular, in the case of EUV exposure, since high sensitivity is generally required, the resin (A) preferably contains a repeating unit containing a protective group that easily undergoes acid decomposition. Specific examples of the repeating unit include -C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ) or -C (R ₀₁ ) (R ₀₂ ) ( A compound represented by OR ₃₉ ) (a structure commonly referred to as an acetal type protecting group) is preferred.

The resin (A) in the present invention can be synthesized and purified according to a conventional method (for example, radical polymerization). For the synthesis method and purification method, see, for example, the descriptions in paragraphs 0201 to 0202 of JP-A-2008-292975.

The weight average molecular weight of the resin (A) in the present invention is 7,000 or more, preferably 7,000 to 200,000, more preferably 7,000 as described above in terms of polystyrene by GPC method. 50,000 to 50,000, still more preferably 7,000 to 40,000,000, particularly preferably 7,000 to 30,000. When the weight average molecular weight is less than 7000, the solubility in an organic developer becomes too high, and there is a concern that a precise pattern cannot be formed.

The degree of dispersion (molecular weight distribution) is usually 1.0 to 3.0, preferably 1.0 to 2.6, more preferably 1.0 to 2.0, and particularly preferably 1.4 to 2.0. Those in the range are used. The smaller the molecular weight distribution, the better the resolution and the resist shape, the smoother the sidewall of the resist pattern, and the better the roughness. In the present invention, the weight average molecular weight (Mw) and number average molecular weight (Mn) of the resin (A) are, for example, HLC-8120 (manufactured by Tosoh Corporation), and TSK カラム gel Multipore HXL-M (Tosoh ( 7.8 mm ID x 30.0 cm can be obtained by using THF (tetrahydrofuran) as an eluent.

In the chemically amplified resist composition of the present invention, the blending ratio of the resin (A) in the entire composition is preferably 30 to 99% by mass, more preferably 60 to 95% by mass in the total solid content.

In the present invention, the resin (A) may be used alone or in combination.

Hereinafter, although the specific example (composition ratio of a repeating unit is a molar ratio) of resin (A) is given, this invention is not limited to these. In addition, below, the aspect in case the structure corresponding to an acid generator (B) mentioned later is carry | supported by resin (A) is also illustrated.

The resin exemplified below is an example of a resin that can be suitably used particularly during EUV exposure or electron beam exposure.

[2] Compound that generates acid upon irradiation with actinic ray or radiation The actinic ray-sensitive or radiation-sensitive resin composition used in the present invention is a compound that generates an acid upon irradiation with actinic ray or radiation (hereinafter referred to as “compound”). (B) "or" acid generator ").

The acid generator may be in the form of a low molecular compound or may be incorporated in a part of the polymer. Further, the form of the low molecular compound and the form incorporated in a part of the polymer may be used in combination.

When the acid generator is in the form of a low molecular compound, the molecular weight is preferably 3000 or less, more preferably 2000 or less, and even more preferably 1000 or less.

When the acid generator is incorporated in a part of the polymer, it may be incorporated in a part of the acid-decomposable resin described above or may be incorporated in a resin different from the acid-decomposable resin.

In the present invention, the acid generator is preferably in the form of a low molecular compound. In one embodiment of the present invention, examples of the acid generator include compounds represented by the following general formula (ZI), (ZII), or (ZIII).

In the general formula (ZI),
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.

The organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.

Two of R ₂₀₁ to R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. Examples of the group formed by combining two _{members out} of R ₂₀₁ to R ₂₀₃ include an alkylene group (eg, butylene group, pentylene group).

In addition, the compound which has two or more structures represented by general formula (ZI) may be sufficient. For example, at least one of R ₂₀₁ to R ₂₀₃ of the compound represented by the general formula (ZI) is a single bond or at least one of R ₂₀₁ to R ₂₀₃ of another compound represented by the general formula (ZI) It may be a compound having a structure bonded through a linking group.

Z ⁻ represents a non-nucleophilic anion (an anion having an extremely low ability to cause a nucleophilic reaction).

Examples of Z ⁻ include a sulfonate anion (an aliphatic sulfonate anion, an aromatic sulfonate anion, a camphor sulfonate anion, etc.), a carboxylate anion (an aliphatic carboxylate anion, an aromatic carboxylate anion, an aralkyl carboxylate anion). Etc.), sulfonylimide anion, bis (alkylsulfonyl) imide anion, tris (alkylsulfonyl) methide anion and the like.

The aliphatic moiety in the aliphatic sulfonate anion and aliphatic carboxylate anion may be an alkyl group or a cycloalkyl group, preferably a linear or branched alkyl group having 1 to 30 carbon atoms and a carbon number. Examples include 3 to 30 cycloalkyl groups.

The aromatic group in the aromatic sulfonate anion and aromatic carboxylate anion is preferably an aryl group having 6 to 14 carbon atoms, such as a phenyl group, a tolyl group, and a naphthyl group.

The alkyl group, cycloalkyl group and aryl group mentioned above may have a substituent. Specific examples thereof include nitro groups, halogen atoms such as fluorine atoms, carboxyl groups, hydroxyl groups, amino groups, cyano groups, alkoxy groups (preferably having 1 to 15 carbon atoms), cycloalkyl groups (preferably having 3 to 15 carbon atoms). ), An aryl group (preferably 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably 2 to 7 carbon atoms), an acyl group (preferably 2 to 12 carbon atoms), an alkoxycarbonyloxy group (preferably 2 to 2 carbon atoms). 7), an alkylthio group (preferably 1 to 15 carbon atoms), an alkylsulfonyl group (preferably 1 to 15 carbon atoms), an alkyliminosulfonyl group (preferably 2 to 15 carbon atoms), an aryloxysulfonyl group (preferably a carbon atom) Number 6 to 20), alkylaryloxysulfonyl group (preferably having 7 to 20 carbon atoms), cycloalkylary Examples thereof include an oxysulfonyl group (preferably having 10 to 20 carbon atoms), an alkyloxyalkyloxy group (preferably having 5 to 20 carbon atoms), a cycloalkylalkyloxyalkyloxy group (preferably having 8 to 20 carbon atoms), and the like. . The aryl group and ring structure of each group may further have an alkyl group (preferably having 1 to 15 carbon atoms) as a substituent.

As the aralkyl group in the aralkyl carboxylate anion, preferably an aralkyl group having 7 to 12 carbon atoms such as benzyl group, phenethyl group, naphthylmethyl group, naphthylethyl group, naphthylbutyl group and the like can be mentioned.

Examples of the sulfonylimide anion include saccharin anion.

The alkyl group in the bis (alkylsulfonyl) imide anion and tris (alkylsulfonyl) methide anion is preferably an alkyl group having 1 to 5 carbon atoms. Examples of substituents for these alkyl groups include halogen atoms, alkyl groups substituted with halogen atoms, alkoxy groups, alkylthio groups, alkyloxysulfonyl groups, aryloxysulfonyl groups, cycloalkylaryloxysulfonyl groups, and the like. A fluorine atom or an alkyl group substituted with a fluorine atom is preferred.

Examples of other Z ⁻ include fluorinated phosphorus (for example, PF ₆ ⁻ ), fluorinated boron (for example, BF ₄ ⁻ ), fluorinated antimony (for example, SbF ₆ ⁻ ), and the like.

Z ⁻ represents an aliphatic sulfonate anion substituted with a fluorine atom at least in the α-position of the sulfonic acid, an aromatic sulfonate anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group substituted with a fluorine atom. Bis (alkylsulfonyl) imide anions and tris (alkylsulfonyl) methide anions in which the alkyl group is substituted with a fluorine atom are preferred.

In one embodiment of the present invention, the number of fluorine atoms contained in the anion as Z ⁻ is preferably 2 or 3.

From the viewpoint of acid strength, the pKa of the generated acid is preferably −1 or less in order to improve sensitivity.

_Examples of the organic group for R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include an aryl group (preferably having 6 to 15 carbon atoms), a linear or branched alkyl group (preferably having 1 to 10 carbon atoms), a cycloalkyl group (having 3 carbon atoms). To 15 are preferred).

Of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ , at least one is preferably an aryl group, more preferably all three are aryl groups. As the aryl group, in addition to a phenyl group, a naphthyl group, and the like, a heteroaryl group such as an indole residue and a pyrrole residue can be used.

These aryl groups, alkyl groups and cycloalkyl groups as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ may further have a substituent. Examples of the substituent include nitro groups, halogen atoms such as fluorine atoms, carboxyl groups, hydroxyl groups, amino groups, cyano groups, alkoxy groups (preferably having 1 to 15 carbon atoms), cycloalkyl groups (preferably having 3 to 15 carbon atoms). ), An aryl group (preferably 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably 2 to 7 carbon atoms), an acyl group (preferably 2 to 12 carbon atoms), an alkoxycarbonyloxy group (preferably 2 to 2 carbon atoms). 7) and the like, but are not limited thereto.

Two selected from R ₂₀₁ , R ₂₀₂ and R ₂₀₃ may be bonded via a single bond or a linking group. Examples of the linking group include an alkylene group (preferably having 1 to 3 carbon atoms), —O—, —S—, —CO—, —SO ₂ — and the like, but are not limited thereto.

Preferred structures when at least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is not an aryl group include paragraphs 0046 and 0047 of JP-A-2004-233661, paragraphs 0040 to 0046 of JP-A-2003-35948, US Compounds exemplified as Formulas (I-1) to (I-70) in Patent Application Publication No. 2003 / 0224288A1, and Formulas (IA-1) to (I) in US Patent Application Publication No. 2003 / 0077540A1 And cation structures such as compounds exemplified as formulas (IA-54) and formulas (IB-1) to (IB-24).

More preferred examples of the compound represented by the general formula (ZI) include compounds represented by the following general formula (ZI-3) or (ZI-4). First, the compound represented by general formula (ZI-3) is demonstrated.

In the general formula (ZI-3),
R ₁ represents an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group or an alkenyl group,
R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, and R ₂ and R ₃ may be linked to each other to form a ring,
R ₁ and R ₂ may combine with each other to form a ring,
R _X and R _y each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, or an alkoxycarbonylcycloalkyl group, R _X and R _y may be connected to each other to form a ring, and this ring structure may contain an oxygen atom, a nitrogen atom, a sulfur atom, a ketone group, an ether bond, an ester bond, or an amide bond.

Z ⁻ represents a non-nucleophilic anion.

The alkyl group as R ₁ is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and may have an oxygen atom, a sulfur atom, or a nitrogen atom in the alkyl chain. Specific examples include branched alkyl groups. The alkyl group of R ₁ may have a substituent.

The cycloalkyl group as R ₁ is preferably a cycloalkyl group having 3 to 20 carbon atoms, and may have an oxygen atom or a sulfur atom in the ring. The cycloalkyl group of R ₁ may have a substituent.

The alkoxy group as R ₁ is preferably an alkoxy group having 1 to 20 carbon atoms. The alkoxy group of R ₁ may have a substituent.

The cycloalkoxy group as R ₁ is preferably a cycloalkoxy group having 3 to 20 carbon atoms. The cycloalkoxy group for R ₁ may have a substituent.

The aryl group as R ₁ is preferably an aryl group having 6 to 14 carbon atoms. The aryl group for R ₁ may have a substituent.

Examples of the alkenyl group as R ₁ include a vinyl group and an allyl group.

R ₂ and R ₃ represent a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group, and R ₂ and R ₃ may be connected to each other to form a ring. However, at least one of R ₂ and R ₃ represents an alkyl group, a cycloalkyl group, or an aryl group. Specific examples and preferred examples of the alkyl group, cycloalkyl group and aryl group for R ₂ and R ₃ include those similar to the specific examples and preferred examples described above for R ₁ . When R ₂ and R ₃ are connected to each other to form a ring, the total number of carbon atoms that contribute to the formation of the ring contained in R ₂ and R ₃ is preferably 4 to 7, and is preferably 4 or 5 It is particularly preferred that

R ₁ and R ₂ may be connected to each other to form a ring. When R ₁ and R ₂ are connected to each other to form a ring, R ₁ is an aryl group (preferably a phenyl group or a naphthyl group which may have a substituent), and R ₂ has 1 to 4 carbon atoms. An alkylene group (preferably a methylene group or an ethylene group) is preferable, and examples of the preferable substituent include the same substituents that the aryl group as R ₁ may have. As another form in the case where R ₁ and R ₂ are connected to each other to form a ring, it is also preferable that R ₁ is a vinyl group and R ₂ is an alkylene group having 1 to 4 carbon atoms.

The alkyl group represented by R _X and R _y is preferably an alkyl group having 1 to 15 carbon atoms.

The cycloalkyl group represented by R _X and R _y is preferably a cycloalkyl group having 3 to 20 carbon atoms.

The alkenyl group represented by R _X and R _y is preferably 2 to 30 alkenyl groups such as a vinyl group, an allyl group, and a styryl group.

The aryl group represented by R _X and R _y is, for example, an aryl group having 6 to 20 carbon atoms, preferably a phenyl group or a naphthyl group, and more preferably a phenyl group.

The alkyl group moiety of the 2-oxoalkyl group and alkoxycarbonylalkyl group represented by R _X and R _y, for example, those previously listed as R _X and R _y.

Examples of the cycloalkyl group part of the 2-oxocycloalkyl group and alkoxycarbonylcycloalkyl group represented by R _X and R _y include those enumerated above as R _X and Ry.

In one embodiment, R _X and R _y are preferably linked to each other to form a ring structure. This ring structure is preferably a 5-membered or 6-membered ring including the sulfur atom of the general formula (ZI-3). In addition, an embodiment in which an ether bond is included in the ring structure is preferable because it can be expected that a decomposition product by irradiation with actinic rays or radiation will be volatilized as outgas.
Z ^- is, for example, Z in the above general formula (ZI) ^- include those listed as.

Specific examples of the cation moiety of the compound represented by the general formula (ZI-3) are given below.

Next, the compound represented by formula (ZI-4) will be described.

In general formula (ZI-4),
R ₁₃ represents a group having a hydrogen atom, a fluorine atom, a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, or a cycloalkyl group. These groups may have a substituent.

When there are a plurality of R _{14 s,} each independently represents a group having a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, a cycloalkylsulfonyl group, or a cycloalkyl group. To express. These groups may have a substituent.

R ₁₅ each independently represents an alkyl group, a cycloalkyl group or a naphthyl group. Two R ₁₅ may be bonded to each other to form a ring, and the atoms constituting the ring may include heteroatoms such as an oxygen atom, a sulfur atom and a nitrogen atom. These groups may have a substituent.

L represents an integer of 0-2.

R represents an integer from 0 to 8.

Z ⁻ represents a non-nucleophilic anion, and examples thereof include the same non-nucleophilic anion as Z ^{− in} formula (ZI).

In the general formula (ZI-4), the alkyl groups of R ₁₃ , R ₁₄ and R ₁₅ are linear or branched, and those having 1 to 10 carbon atoms are preferable.

Examples of the cycloalkyl group represented by R ₁₃ , R ₁₄ and R ₁₅ include a monocyclic or polycyclic cycloalkyl group.

The alkoxy group for R ₁₃ and R ₁₄ is preferably linear or branched and has 1 to 10 carbon atoms.

The alkoxycarbonyl group for R ₁₃ and R ₁₄ is preferably linear or branched and has 2 to 11 carbon atoms.

Examples of the group having a cycloalkyl group of R ₁₃ and R ₁₄ include a group having a monocyclic or polycyclic cycloalkyl group. These groups may further have a substituent.

The alkyl group of the alkyl group of R _14, include the same specific examples and the alkyl group as R _{13 ~} R ₁₅ described above.

The alkylsulfonyl group and cycloalkylsulfonyl group for R ₁₄ are linear, branched, or cyclic and preferably have 1 to 10 carbon atoms.

Examples of the substituent that each of the above groups may have include a halogen atom (for example, a fluorine atom), a hydroxyl group, a carboxyl group, a cyano group, a nitro group, an alkoxy group, an alkoxyalkyl group, an alkoxycarbonyl group, and an alkoxycarbonyloxy group. Etc.

As the ring structure that two R ₁₅ may be bonded to each other, a 5-membered or 6-membered ring formed by two R ₁₅ together with a sulfur atom in the general formula (ZI-4), particularly preferably Includes a 5-membered ring (that is, a tetrahydrothiophene ring or a 2,5-dihydrothiophene ring), and may be condensed with an aryl group or a cycloalkyl group. These two R ₁₅ may have a substituent. Examples of the substituent include a hydroxyl group, a carboxyl group, a cyano group, a nitro group, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxyalkyl group, and an alkoxycarbonyl group. Group, alkoxycarbonyloxy group and the like. There may be a plurality of substituents for the ring structure, or they may be bonded to each other to form a ring.

R ₁₅ in the general formula (ZI-4) is preferably a methyl group, an ethyl group, a naphthyl group, or a divalent group in which two R ¹⁵ are bonded to each other to form a tetrahydrothiophene ring structure together with a sulfur atom. A divalent group in which two R ¹⁵ are bonded to each other to form a tetrahydrothiophene ring structure together with a sulfur atom is particularly preferable.

The substituent that R ₁₃ and R ₁₄ may have is preferably a hydroxyl group, an alkoxy group, an alkoxycarbonyl group, or a halogen atom (particularly a fluorine atom).

l is preferably 0 or 1, and more preferably 1.
r is preferably from 0 to 2.

Specific examples of the cation structure possessed by the compound represented by the general formula (ZI-3) or (ZI-4) described above include the above-mentioned JP-A-2004-233661, JP-A-2003-35948, In addition to cationic structures such as compounds exemplified in US Patent Application Publication No. 2003 / 0224288A1 and US Patent Application Publication No. 2003 / 0077540A1, for example, paragraphs 0046 and 0047 of JP2011-53360A Cation structures in chemical structures and the like exemplified in 0072-0077 and 0107-0110, and cation structures in chemical structures exemplified in paragraphs 0135 to 0137, 0151 and 0196 to 0199 of JP2011-53430, etc. Is mentioned.

In general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an aryl group, an alkyl group, or a cycloalkyl group.

The aryl group, alkyl group, and cycloalkyl group of R ₂₀₄ to R ₂₀₇ are the same as the aryl group, alkyl group, and cycloalkyl group of R ₂₀₁ to R ₂₀₃ in the aforementioned compound (ZI).

The aryl group, alkyl group, and cycloalkyl group of R ₂₀₄ to R ₂₀₇ may have a substituent. Examples of this substituent include those that the aryl group, alkyl group, and cycloalkyl group of R ₂₀₁ to R ₂₀₃ in the aforementioned compound (ZI) may have.

Z ^- is, for example, Z in the above general formula (ZI) ^- include those listed as.

Then, non-nucleophilic anion Z ^- is described in the preferred construction.

Non-nucleophilic anion Z ^- is is preferably a sulfonate anion represented by formula (2).

In the general formula (2), Xf each independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom.

R ₇ and R ₈ each independently represent a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom, and when there are a plurality of R ₇ and R ₈ , R ₇ and R ₈ are the same But it can be different.

L represents a divalent linking group, and when there are a plurality of L, L may be the same or different.

A represents an organic group containing a cyclic structure.

X represents an integer of 1-20. y represents an integer of 0 to 10. z represents an integer of 0 to 10.

The anion of the general formula (2) will be described in more detail.

Xf is a fluorine atom or an alkyl group substituted with at least one fluorine atom as described above, and the alkyl group in the alkyl group substituted with a fluorine atom is preferably an alkyl group having 1 to 10 carbon atoms, An alkyl group having 1 to 4 carbon atoms is more preferable. The alkyl group substituted with a fluorine atom of Xf is preferably a perfluoroalkyl group.

Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms. Specifically, a fluorine atom or CF ₃ is preferable. In particular, it is preferable that both Xf are fluorine atoms.

As described above, R ₇ and R ₈ represent a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom, and the alkyl group preferably has 1 to 4 carbon atoms. More preferred is a perfluoroalkyl group having 1 to 4 carbon atoms. As a specific example of the alkyl group substituted with at least one fluorine atom of R ₇ and R ₈ , CF ₃ is preferable.

L represents a divalent linking group, and represents —COO—, —OCO—, —CO—, —O—, —S—, —SO—, —SO ₂ —, —N (Ri) — (wherein Ri represents a hydrogen atom or alkyl), an alkylene group (preferably 1 to 6 carbon atoms), a cycloalkylene group (preferably 3 to 10 carbon atoms), an alkenylene group (preferably 2 to 6 carbon atoms), or a plurality of these And a divalent linking group in combination of —COO—, —OCO—, —CO—, —SO ₂ —, —CON (Ri) —, —SO ₂ N (Ri) —, —CON (Ri ) -Alkylene group-, -N (Ri) CO-alkylene group-, -COO-alkylene group- or -OCO-alkylene group-, preferably -COO-, -OCO-, -SO ₂ -,- CON (Ri)-or -SO ₂ N (Ri)- Is more preferable. When there are a plurality of L, they may be the same or different.

The alkyl group as Ri is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and may have an oxygen atom, a sulfur atom, or a nitrogen atom in the alkyl chain. Specific examples include straight chain alkyl groups and branched alkyl groups. Examples of the alkyl group having a substituent include a cyanomethyl group, a 2,2,2-trifluoroethyl group, a methoxycarbonylmethyl group, and an ethoxycarbonylmethyl group.

The organic group containing the cyclic structure of A is not particularly limited as long as it has a cyclic structure, and is not limited to alicyclic groups, aryl groups, and heterocyclic groups (not only those having aromaticity but also aromaticity). For example, a tetrahydropyran ring and a lactone ring structure are also included).

The alicyclic group may be monocyclic or polycyclic. Also preferred are nitrogen atom-containing alicyclic groups such as piperidine group, decahydroquinoline group, decahydroisoquinoline group. Among them, it has a bulky structure with 7 or more carbon atoms such as norbornyl group, tricyclodecanyl group, tetracyclodecanyl group, tetracyclododecanyl group, adamantyl group, decahydroquinoline group, decahydroisoquinoline group, steroid skeleton, etc. An alicyclic group is preferable from the viewpoint of improving exposure latitude because it can suppress in-film diffusibility in the PEB (post-exposure heating) step.

Examples of the aryl group include a benzene ring, a naphthalene ring, a phenanthrene ring, and an anthracene ring. Among these, a naphthalene ring having a low absorbance is preferable from the viewpoint of light absorbance at 193 nm.

Examples of the heterocyclic group include a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a pyridine ring. Of these, a furan ring, a thiophene ring, and a pyridine ring are preferable.

The cyclic organic group may have a substituent, and examples of the substituent include an alkyl group (which may be linear, branched or cyclic, preferably 1 to 12 carbon atoms), aryl Group (preferably having 6 to 14 carbon atoms), hydroxy group, alkoxy group, ester group, amide group, urethane group, ureido group, thioether group, sulfonamide group, sulfonic acid ester group, cyano group and the like.

Note that the carbon constituting the organic group containing a cyclic structure (carbon contributing to ring formation) may be a carbonyl carbon.

X is preferably 1 to 8, more preferably 1 to 4, and particularly preferably 1. y is preferably 0 to 4, more preferably 0 or 1, and still more preferably 0. z is preferably 0 to 8, more preferably 0 to 4, and still more preferably 1.

In one embodiment of the present invention, the number of fluorine atoms contained in the anion represented by the general formula (2) is preferably 2 or 3. Thereby, the effect of the present invention can be further enhanced.

Specific examples of the sulfonate anion structure represented by the general formula (2) are given below, but the present invention is not limited thereto.

Z ⁻ is also preferably a sulfonate anion represented by the following general formula (B-1).

In the general formula (B-1),
R _b1 each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group (CF ₃ ).

N represents an integer from 0 to 4.

N is preferably an integer of 0 to 3, more preferably 0 or 1.

X _b1 represents a single bond, an alkylene group, an ether bond, an ester bond (—OCO— or —COO—), a sulfonate ester bond (—OSO ₂ — or —SO ₃ —), or a combination thereof.

X _b1 is preferably an ester bond (—OCO— or —COO—) or a sulfonate bond (—OSO ₂ — or —SO ₃ —), and preferably an ester bond (—OCO— or —COO—). Is more preferable.

R _b2 represents an organic group having 6 or more carbon atoms.

The organic group having 6 or more carbon atoms for R _b2 is preferably a bulky group, and examples thereof include alkyl groups, alicyclic groups, aryl groups, and heterocyclic groups having 6 or more carbon atoms.

The alkyl group having 6 or more carbon atoms for R _b2 may be linear or branched, and is preferably a linear or branched alkyl group having 6 to 20 carbon atoms. Examples thereof include a linear or branched hexyl group, a linear or branched heptyl group, and a linear or branched octyl group. From the viewpoint of bulkiness, a branched alkyl group is preferable.

The alicyclic group having 6 or more carbon atoms for R _b2 may be monocyclic or polycyclic. Among them, an alicyclic group having a bulky structure having 7 or more carbon atoms such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group is used in a PEB (post-exposure heating) step. Of diffusion in membrane and MEEF (Mask)
It is preferable from the viewpoint of improving the error enhancement factor.

The aryl group having 6 or more carbon atoms for R _b2 may be monocyclic or polycyclic. Examples of the aryl group include a phenyl group, a naphthyl group, a phenanthryl group, and an anthryl group. Among these, a naphthyl group having a relatively low light absorbance at 193 nm is preferable.

The heterocyclic group having 6 or more carbon atoms for R _b2 may be monocyclic or polycyclic, but polycyclic can suppress acid diffusion more. Moreover, the heterocyclic group may have aromaticity or may not have aromaticity. Examples of the heterocyclic ring having aromaticity include a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, and a dibenzothiophene ring. Examples of the heterocyclic ring not having aromaticity include a tetrahydropyran ring, a lactone ring, a sultone ring, and a decahydroisoquinoline ring.

The substituent having 6 or more carbon atoms for R _b2 may further have a substituent. Examples of the further substituent include an alkyl group (which may be linear or branched, preferably 1 to 12 carbon atoms) and a cycloalkyl group (monocyclic, polycyclic or spiro ring). And preferably having 3 to 20 carbon atoms), aryl group (preferably having 6 to 14 carbon atoms), hydroxy group, alkoxy group, ester group, amide group, urethane group, ureido group, thioether group, sulfonamide group, And sulfonic acid ester groups. The carbon constituting the alicyclic group, aryl group, or heterocyclic group (carbon contributing to ring formation) may be a carbonyl carbon.

Specific examples of the sulfonate anion structure represented by formula (B-1) are shown below, but the present invention is not limited thereto. In addition, what corresponds to the sulfonate anion represented by General formula (2) mentioned above is also contained in the following specific example.

Z ⁻ is also preferably a sulfonate anion represented by the following general formula (AI).

In general formula (AI),
R ₁ is an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, or a heteroaryl group.

R ₂ is a divalent linking group.

Rf is a fluorine atom or an alkyl group substituted with at least one fluorine atom.

n ₁ and n ₂ are each independently 0 or 1.

The alkyl group represented by R ₁ is preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, and an alkyl group having 1 to 5 carbon atoms. It is more preferable that the alkyl group has 1 to 4 carbon atoms.

The alkyl group may have a substituent (preferably a fluorine atom), and the alkyl group having a substituent is preferably a perfluoroalkyl group having 1 to 5 carbon atoms.

The monovalent alicyclic hydrocarbon group represented by R ₁ preferably has 5 or more carbon atoms. The monovalent alicyclic hydrocarbon group preferably has 20 or less carbon atoms, and more preferably 15 or less. The monovalent alicyclic hydrocarbon group may be a monocyclic alicyclic hydrocarbon group or a polycyclic alicyclic hydrocarbon group. A part of —CH ₂ — of the alicyclic hydrocarbon group may be substituted with —O— or —C (═O) —.

As the monocyclic alicyclic hydrocarbon group, those having 5 to 12 carbon atoms are preferable, and a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group are preferable.

As the polycyclic alicyclic hydrocarbon group, those having 10 to 20 carbon atoms are preferable, and norbornyl group, adamantyl group and noradamantyl group are preferable.

The aryl group represented by R ₁ preferably has 6 or more carbon atoms. The aryl group preferably has 20 or less carbon atoms, and more preferably 15 or less.

The heteroaryl group represented by R ₁ preferably has 2 or more carbon atoms. The heteroaryl group preferably has 20 or less carbon atoms, more preferably 15 or less.

The aryl group and heteroaryl group may be a monocyclic aryl group or a monocyclic heteroaryl group, or may be a polycyclic aryl group or a polycyclic heteroaryl group. Specific examples include a phenyl group, a naphthyl group, an anthracenyl group, a pyridyl group, a thienyl group, a furanyl group, a quinolyl group, and an isoquinolyl group.

The monovalent alicyclic hydrocarbon group, aryl group, and heteroaryl group as R ₁ may further have a substituent. Examples of such a further substituent include a hydroxyl group, a halogen atom, Atom (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), nitro group, cyano group, amide group, sulfonamido group, alkyl group, alkoxy group, alkoxycarbonyl group, acyl group, acyloxy group, carboxy group .
R ₁ is particularly preferably a cyclohexyl group or an adamantyl group.

The divalent linking group represented by R ₂ is not particularly limited, but is —COO—, —OCO—, —CO—, —O—, —S—, —SO—, —SO ₂ —, alkylene. A group (preferably an alkylene group having 1 to 30 carbon atoms), a cycloalkylene group (preferably a cycloalkylene group having 3 to 30 carbon atoms), an alkenylene group (preferably an alkenylene group having 2 to 30 carbon atoms), an arylene group (preferably May be an arylene group having 6 to 30 carbon atoms), a heteroarylene group (preferably a heteroarylene group having 2 to 30 carbon atoms), or a group in which two or more of these are combined. The above alkylene group, cycloalkylene group, alkenylene group, arylene group and heteroarylene group may further have a substituent, and specific examples of such a substituent include a monovalent alicyclic ring as R _1. The substituents that the hydrocarbon group, aryl group, and heteroaryl group may further have are the same as those described above.

The divalent linking group represented by R ₂ is preferably an alkylene group, a cycloalkylene group, an alkenylene group, an arylene group or a heteroarylene group, more preferably an alkylene group, and further an alkylene group having 1 to 10 carbon atoms. An alkylene group having 1 to 5 carbon atoms is preferable.

Rf is a fluorine atom or an alkyl group substituted with at least one fluorine atom. More preferably, the alkyl group has 1 to 4 carbon atoms. The alkyl group substituted with at least one fluorine atom is preferably a perfluoroalkyl group. More specifically, Rf is preferably a fluorine atom or CF ₃ .

n ₁ is preferably 1.

n ₂ is preferably 1.

Preferred specific examples of the sulfonate anion represented by the general formula (AI) are shown below, but the present invention is not limited thereto. In addition, what corresponds to the sulfonate anion represented by General formula (2) mentioned above is also contained in the following specific example.

The non-nucleophilic anion Z ⁻ may be a disulfonyl imido acid anion represented by the general formula (2 ′).

In general formula (2 ′),
Xf is as defined in the general formula (2), and preferred examples are also the same. In the general formula (2 ′), two Xf's may be linked to each other to form a ring structure.

Z ^- The disulfonylimide anion of, preferably a bis (alkylsulfonyl) imide anion.

The alkyl group in the bis (alkylsulfonyl) imide anion is preferably an alkyl group having 1 to 5 carbon atoms.

The two alkyl groups in the bis (alkylsulfonyl) imide anion may be linked to each other to form an alkylene group (preferably having 2 to 4 carbon atoms) and form a ring together with the imide group and the two sulfonyl groups. The ring structure that may be formed by the bis (alkylsulfonyl) imide anion is preferably a 5- to 7-membered ring, and more preferably a 6-membered ring.

These alkyl groups and alkylene groups formed by connecting two alkyl groups to each other can have a halogen atom, an alkyl group substituted with a halogen atom, an alkoxy group, an alkylthio group, an alkyloxysulfonyl group, an aryl Examples thereof include an oxysulfonyl group and a cycloalkylaryloxysulfonyl group, and a fluorine atom or an alkyl group substituted with a fluorine atom is preferred.

Examples of the acid generator further include compounds represented by the following general formula (ZV).

In general formula (ZV),
R ₂₀₈ represents an alkyl group, a cycloalkyl group or an aryl group.

A represents an alkylene group, an alkenylene group or an arylene group.

Specific examples of the aryl group of R ₂₀₈ include the same examples as the specific examples of the aryl group as R ₂₀₁ to R ₂₀₃ in the general formula (ZI).

Specific examples of the alkyl group and cycloalkyl group represented by R ₂₀₈ include the same examples as the specific examples of the alkyl group and cycloalkyl group represented by R ₂₀₁ to R ₂₀₃ in the general formula (ZI).

The alkylene group of A is an alkylene group having 1 to 12 carbon atoms, the alkenylene group of A is an alkenylene group having 2 to 12 carbon atoms, and the arylene group of A is an arylene group having 6 to 10 carbon atoms. , Can be mentioned respectively.

Examples of acid generators are listed below. However, the present invention is not limited to these.

The acid generator can be synthesized by a known method. For example, <0200> to <0210> of JP2007-161707A, JP2010-1007055A and <2011/02093280 < 0051> to <0058>, <0382> to <0385> of International Publication No. 2008/153110, Japanese Patent Application Laid-Open No. 2007-161707, and the like.

The acid generator can be used alone or in combination of two or more.

The content of the compound that generates an acid upon irradiation with actinic rays or radiation in the composition is preferably 0.1 to 30% by mass, more preferably 0.5%, based on the total solid content of the composition of the present invention. -25% by mass, more preferably 3-20% by mass, particularly preferably 3-15% by mass.

In addition, depending on the actinic ray-sensitive or radiation-sensitive resin composition, there is an embodiment (B ′) in which a structure corresponding to the acid generator is supported on the resin (A). Specifically, as such an embodiment, a structure described in JP2011-248019A (particularly, a structure described in paragraphs 0164 to 0191, a structure included in the resin described in the example in paragraph 0555). And the repeating unit (R) described in paragraphs 0023 to 0210 of JP2013-80002A. Incidentally, even if the structure corresponding to the acid generator is supported by the resin (A), the actinic ray-sensitive or radiation-sensitive resin composition is additionally added to the resin (A). An unsupported acid generator may be included.

Examples of the embodiment (B ′) include the following repeating units, but are not limited thereto.

[3] Solvent The composition of the present invention usually contains a solvent.
Solvents that can be used in preparing the composition of the present invention include, for example, alkylene glycol monoalkyl ether carboxylates, alkylene glycol monoalkyl ethers, alkyl lactate esters, alkyl alkoxypropionates, cyclic lactones (preferably carbon And organic solvents such as monoketone compounds (preferably having 4 to 10 carbon atoms), alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate.

Specific examples of these solvents include those described in US Patent Application Publication No. 2008/0187860 <0441> to <0455>.

In the present invention, a plurality of kinds of organic solvents may be mixed and used.

For example, you may use the mixed solvent which mixed the solvent which contains a hydroxyl group in a structure, and the solvent which does not contain a hydroxyl group as an organic solvent. As the solvent containing a hydroxyl group and the solvent not containing a hydroxyl group, the above-mentioned exemplary compounds can be selected as appropriate. As the solvent containing a hydroxyl group, alkylene glycol monoalkyl ether, alkyl lactate and the like are preferable, and propylene glycol monomethyl ether ( PGME, also known as 1-methoxy-2-propanol), ethyl lactate is more preferred. Further, as the solvent not containing a hydroxyl group, alkylene glycol monoalkyl ether acetate, alkyl alkoxypropionate, monoketone compound which may contain a ring, cyclic lactone, alkyl acetate and the like are preferable, and among these, propylene glycol monomethyl ether Acetate (PGMEA, also known as 1-methoxy-2-acetoxypropane), ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate are particularly preferred, propylene glycol monomethyl ether acetate, ethyl ethoxypropionate, 2 -Heptanone is most preferred.

Of course, organic solvents that do not contain a hydroxyl group in the structure can be used together. Examples of this combination include PGMEA and cyclohexanone, PGMEA and cyclopentanone, PGMEA and γ-butyrolactone, PGMEA and 2-heptanone, and the like.

For example, when two kinds of solvents are used, the mixing ratio (mass) is 1/99 to 99/1, preferably 10/90 to 90/10, and more preferably 20/80 to 60/40.

The solvent preferably includes propylene glycol monomethyl ether acetate, and is preferably a propylene glycol monomethyl ether acetate single solvent or a mixed solvent of two or more containing propylene glycol monomethyl ether acetate.

When a suitable amount of a solvent having a relatively high boiling point such as γ-butyrolactone is used, it can be expected that the hydrophobic resin (D) described later is more unevenly distributed on the surface and the performance for immersion exposure is improved.

Further, three or more solvents may be used. As a result, fine adjustment of resist shape, adjustment of viscosity, and the like may be performed. Examples of the combinations include PGMEA · PGME · γ-butyrolactone, PGMEA · PGME · cyclohexanone, PGMEA · PGME · 2-heptanone, PGMEA · cyclohexanone · γ-butyrolactone, PGMEA · γ-butyrolactone · 2-heptanone, and the like.

[4] Hydrophobic resin (D)
The composition of the present invention may contain a hydrophobic resin (hereinafter also referred to as “hydrophobic resin (D)” or simply “resin (D)”), particularly when applied to immersion exposure. The hydrophobic resin (D) is preferably different from the resin (A).

As a result, the hydrophobic resin (D) is unevenly distributed in the film surface layer, and when the immersion medium is water, the static / dynamic contact angle of the resist film surface with water is improved, and the immersion liquid followability is improved. be able to.

The hydrophobic resin may be included for various purposes even when the composition is not applied to immersion exposure. For example, when the composition is applied to EUV exposure, it is also preferable to use a hydrophobic resin in anticipation of outgas suppression and pattern shape adjustment.

The hydrophobic resin (D) is preferably designed to be unevenly distributed at the interface as described above. However, unlike the surfactant, the hydrophobic resin (D) does not necessarily need to have a hydrophilic group in the molecule. There is no need to contribute to uniform mixing.

The hydrophobic resin (D) is selected from any one of “fluorine atom”, “silicon atom”, and “CH ₃ partial structure contained in the side chain portion of the resin” from the viewpoint of uneven distribution in the film surface layer. It is preferable to have the above, and it is more preferable to have two or more.

The weight average molecular weight in terms of standard polystyrene of the hydrophobic resin (D) is preferably 1,000 to 100,000, more preferably 1,000 to 50,000, still more preferably 2,000 to 15,000. is there.

Further, the hydrophobic resin (D) may be used alone or in combination.

The content of the hydrophobic resin (D) in the composition is preferably 0.01 to 10% by mass, more preferably 0.05 to 8% by mass, based on the total solid content in the composition of the present invention. More preferably, it is 1 to 7% by mass.

The hydrophobic resin (D), like the resin (A), naturally has few impurities such as metals, and the residual monomer or oligomer component is preferably 0.01 to 5% by mass, more preferably Is more preferably 0.01 to 3% by mass and 0.05 to 1% by mass. As a result, a chemically amplified resist composition having no change over time such as foreign matter in liquid or sensitivity can be obtained. The molecular weight distribution (Mw / Mn, also referred to as dispersity) is preferably in the range of 1 to 5, more preferably 1 to 3, and still more preferably from the viewpoints of resolution, resist shape, resist pattern sidewall, roughness, and the like. It is in the range of 1-2.

As the hydrophobic resin (D), various commercially available products can be used, and the hydrophobic resin (D) can be synthesized according to a conventional method (for example, radical polymerization). For example, as a general synthesis method, a monomer polymerization method in which a monomer species and an initiator are dissolved in a solvent and the polymerization is performed by heating, and a solution of the monomer species and the initiator is dropped into the heating solvent over 1 to 10 hours. The dropping polymerization method is added, and the dropping polymerization method is preferable.

The reaction solvent, the polymerization initiator, the reaction conditions (temperature, concentration, etc.) and the purification method after the reaction are the same as those described for the resin (A), but in the synthesis of the hydrophobic resin (D), The concentration of the reaction is preferably 30 to 50% by mass. For more details, refer to the description in the vicinity of paragraphs 0320 to 0329 in JP-A-2008-292975.

Specific examples of the hydrophobic resin (D) are shown below. The following table shows the molar ratio of repeating units in each resin (corresponding to each repeating unit in order from the left), the weight average molecular weight, and the degree of dispersion.

[5] Basic compound The composition of the present invention preferably contains a basic compound.

(1) In one form, the composition of the present invention is also referred to as a basic compound or an ammonium salt compound (hereinafter referred to as “compound (N)”) whose basicity is reduced by irradiation with actinic rays or radiation. ) Is preferably contained.

The compound (N) is preferably a compound (N-1) having a basic functional group or an ammonium group and a group that generates an acidic functional group upon irradiation with actinic rays or radiation. That is, the compound (N) is a basic compound having a basic functional group and a group capable of generating an acidic functional group upon irradiation with actinic light or radiation, or an acidic functional group upon irradiation with an ammonium group and active light or radiation. An ammonium salt compound having a group to be generated is preferable.

Specific examples of the compound (N) include the following. In addition to the compounds listed below, examples of the compound (N) include the compounds (A-1) to (A-44) described in US Patent Application Publication No. 2010/0233629, and US patent applications. The compounds (A-1) to (A-23) described in JP 2012/0156617 A can also be preferably used in the present invention.

These compounds can be synthesized according to the synthesis examples described in JP-A-2006-330098.

The molecular weight of the compound (N) is preferably 500 to 1,000.

The composition of the present invention may or may not contain the compound (N), but when it is contained, the content of the compound (N) is from 0.1 to 0.1 on the basis of the solid content of the composition. It is preferably 20% by mass, more preferably 0.1 to 10% by mass.

(2) In another form, the composition of the present invention is different from the above compound (N) as a basic compound in order to reduce the change in performance over time from exposure to heating. ) May be contained.

Preferred examples of the basic compound (N ′) include compounds having structures represented by the following formulas (A ′) to (E ′).

In general formulas (A ′) and (E ′):
RA ²⁰⁰ , RA ²⁰¹ and RA ²⁰² may be the same or different and are a hydrogen atom, an alkyl group (preferably having a carbon number of 1 to 20), a cycloalkyl group (preferably having a carbon number of 3 to 20) or an aryl group (having a carbon number of 6-20), where RA ²⁰¹ and RA ²⁰² may combine with each other to form a ring. RA ²⁰³ , RA ²⁰⁴ , RA ²⁰⁵ and RA ²⁰⁶ may be the same or different and each represents an alkyl group (preferably having 1 to 20 carbon atoms).

The alkyl group may have a substituent. Examples of the alkyl group having a substituent include an aminoalkyl group having 1 to 20 carbon atoms, a hydroxyalkyl group having 1 to 20 carbon atoms, and a carbon group having 1 to 20 carbon atoms. A cyanoalkyl group is preferred.

These alkyl groups in general formulas (A ′) and (E ′) are more preferably unsubstituted.

Specific examples of the basic compound (N ′) include guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, piperidine, and more preferable specific examples include an imidazole structure. , Diazabicyclo structure, onium hydroxide structure, onium carboxylate structure, trialkylamine structure, aniline structure or pyridine structure compound, alkylamine derivative having hydroxyl group and / or ether bond, aniline derivative having hydroxyl group and / or ether bond Etc.

Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, benzimidazole and the like. Examples of the compound having a diazabicyclo structure include 1,4-diazabicyclo [2,2,2] octane, 1,5-diazabicyclo [4,3,0] non-5-ene, 1,8-diazabicyclo [5,4, 0] Undecaker 7-ene and the like. Examples of the compound having an onium hydroxide structure include triarylsulfonium hydroxide, phenacylsulfonium hydroxide, sulfonium hydroxide having a 2-oxoalkyl group, specifically, triphenylsulfonium hydroxide, tris (t-butylphenyl) Examples include sulfonium hydroxide, bis (t-butylphenyl) iodonium hydroxide, phenacylthiophenium hydroxide, 2-oxopropylthiophenium hydroxide, and the like. The compound having an onium carboxylate structure is a compound having an onium hydroxide structure in which the anion moiety is converted to a carboxylate, and examples thereof include acetate, adamantane-1-carboxylate, and perfluoroalkylcarboxylate. Examples of the compound having a trialkylamine structure include tri (n-butyl) amine and tri (n-octyl) amine. Examples of the compound having an aniline structure include 2,6-diisopropylaniline, N, N-dimethylaniline, N, N-dibutylaniline, N, N-dihexylaniline and the like. Examples of the alkylamine derivative having a hydroxyl group and / or an ether bond include ethanolamine, diethanolamine, triethanolamine, and tris (methoxyethoxyethyl) amine. Examples of aniline derivatives having a hydroxyl group and / or an ether bond include N, N-bis (hydroxyethyl) aniline.

Preferred examples of the basic compound further include an amine compound having a phenoxy group, an ammonium salt compound having a phenoxy group, an amine compound having a sulfonic acid ester group, and an ammonium salt compound having a sulfonic acid ester group. Specific examples thereof include, but are not limited to, compounds (C1-1) to (C3-3) exemplified in <0066> of US Patent Application Publication No. 2007/0224539. Absent.

A nitrogen-containing organic compound having a more leaving group may be contained. As an example of this compound, for example, specific examples of the compound are shown below.

The above compound can be synthesized, for example, according to the method described in JP-A-2009-199021.

Further, as the basic compound (N ′), a compound having an amine oxide structure can also be used. Specific examples of this compound include triethylamine pyridine N-oxide, tributylamine N-oxide, triethanolamine N-oxide, tris (methoxyethyl) amine N-oxide, tris (2- (methoxymethoxy) ethyl) amine = oxide. 2,2 ', 2 "-nitrilotriethylpropionate N-oxide, N-2- (2-methoxyethoxy) methoxyethylmorpholine N-oxide, and other amine oxide compounds exemplified in JP-A-2008-102383 Is possible.

The molecular weight of the basic compound (N ′) is preferably 250 to 2000, more preferably 400 to 1000. From the viewpoint of further reduction in LWR and uniformity of local pattern dimensions, the molecular weight of the basic compound is preferably 400 or more, more preferably 500 or more, and even more preferably 600 or more. .

These basic compounds (N ′) may be used in combination with the above compound (N), or may be used alone or in combination of two or more.

The chemically amplified resist composition in the present invention may or may not contain the basic compound (N ′), but when it is contained, the amount of the basic compound (N ′) used depends on the chemically amplified resist composition. Based on the solid content of the product, it is usually 0.001 to 10% by mass, preferably 0.01 to 5% by mass.

(4) In another form, the composition of the present invention may contain an onium salt represented by the following general formula (6A) or (6B) as a basic compound. This onium salt is expected to control the diffusion of the generated acid in the resist system in relation to the acid strength of the photoacid generator usually used in the resist composition.

In general formula (6A),
Ra represents an organic group. However, those in which a fluorine atom is substituted for a carbon atom directly bonded to a carboxylic acid group in the formula are excluded.

X ⁺ represents an onium cation.

In general formula (6B),
Rb represents an organic group. However, those in which a fluorine atom is substituted for a carbon atom directly bonded to the sulfonic acid group in the formula are excluded.

X ⁺ represents an onium cation.

In the organic group represented by Ra and Rb, the atom directly bonded to the carboxylic acid group or sulfonic acid group in the formula is preferably a carbon atom. However, in this case, in order to make the acid relatively weaker than the acid generated from the above-mentioned photoacid generator, the fluorine atom does not substitute for the carbon atom directly bonded to the sulfonic acid group or carboxylic acid group.

Examples of the organic group represented by Ra and Rb include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, and an aralkyl group having 7 to 30 carbon atoms. Alternatively, a heterocyclic group having 3 to 30 carbon atoms can be used. In these groups, some or all of the hydrogen atoms may be substituted.

Examples of the substituent that the alkyl group, cycloalkyl group, aryl group, aralkyl group and heterocyclic group may have include a hydroxyl group, a halogen atom, an alkoxy group, a lactone group, and an alkylcarbonyl group.

Examples of the onium cation represented by X ⁺ in the general formulas (6A) and (6B) include a sulfonium cation, an ammonium cation, an iodonium cation, a phosphonium cation, and a diazonium cation. Among these, a sulfonium cation is more preferable.

As the sulfonium cation, for example, an arylsulfonium cation having at least one aryl group is preferable, and a triarylsulfonium cation is more preferable. The aryl group may have a substituent, and the aryl group is preferably a phenyl group.

As examples of the sulfonium cation and the iodonium cation, the structure described in the compound (B) can also be preferably mentioned.

A specific structure of the onium salt represented by the general formula (6A) or (6B) is shown below.

(5) In another form, the composition of the present invention is a compound included in the formula (I) of JP2012-189977A, or a compound of formula (I) of JP2013-6827A as a basic compound. Onium in one molecule such as a compound represented by formula (I) in JP2013-8020A, a compound represented by formula (I) in JP2012-252124A, and the like A compound having both a salt structure and an acid anion structure (hereinafter also referred to as a betaine compound) may also be contained. Examples of the onium salt structure include a sulfonium, iodonium, and ammonium structure, and a sulfonium or iodonium salt structure is preferable. The acid anion structure is preferably a sulfonate anion or a carboxylic acid anion. Examples of this compound include the following.

[6] Surfactant The composition of the present invention may further contain a surfactant. When the composition of the present invention contains a surfactant, fluorine and / or silicon surfactant (fluorine surfactant, silicon surfactant, surfactant having both fluorine and silicon atoms) It is more preferable to contain either one or two or more.

When the composition of the present invention contains a surfactant, when using an exposure light source of 250 nm or less, particularly 220 nm or less, it is possible to provide a resist pattern with less adhesion and development defects with good sensitivity and resolution. Become.

Examples of the fluorine-based and / or silicon-based surfactant include surfactants described in <0276> of US Patent Application Publication No. 2008/0248425, such as Fluorard FC430, 431, 4430 (Sumitomo 3M Co., Ltd.). ), Megafuck Series (manufactured by DIC Corporation), Surflon S-382, SC101, 102, 103, 104, 105, 106, KH-20 (manufactured by Asahi Glass Co., Ltd.), Troisol S-366 (Troy Chemical ( GF-300, GF-150 (manufactured by Toagosei Chemical Co., Ltd.), Surflon S-393 (manufactured by Seimi Chemical Co., Ltd.), EFtop EF121, EF122A, EF122B, RF122C, EF125M, EF135M, EF351 , EF352, EF801, EF802, EF601 (Co., Ltd.) Made mucopolysaccharides), PF636, PF656, PF6320, PF6520, and the like (manufactured by OMNOVA Inc.), FTX-204G, 208G, 218G, 230G, 204D, 208D, 212D, 218D, 222D ((Ltd.) Neos). Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

In addition to the known surfactants described above, surfactants are derived from fluoroaliphatic compounds produced by the telomerization method (also referred to as the telomer method) or the oligomerization method (also referred to as the oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.

As surfactants corresponding to the above surfactants, Megafac F178, F-470, F-473, F-475, F-476, F-472 (manufactured by DIC Corporation), C ₆ F ₁₃ group Copolymer of acrylate (or methacrylate) and (poly (oxyalkylene)) acrylate (or methacrylate), acrylate (or methacrylate) and (poly (oxyethylene)) acrylate (or methacrylate) having a C ₃ F ₇ group And a copolymer of (poly (oxypropylene)) acrylate (or methacrylate).

In the present invention, surfactants other than the fluorine-based and / or silicon-based surfactants described in <0280> of US Patent Application Publication No. 2008/0248425 can also be used.

These surfactants may be used alone or in some combination.

When the composition of the present invention contains a surfactant, the amount of the surfactant used is preferably 0.0001 to 2% by mass, more preferably 0, based on the total amount of the composition (excluding the solvent). 0005 to 1% by mass.

On the other hand, when the amount of the surfactant added is 10 ppm or less with respect to the total amount of the actinic ray-sensitive or radiation-sensitive resin composition (excluding the solvent), the surface unevenness of the hydrophobic resin is increased. As a result, the surface of the resist film can be made more hydrophobic, and the water followability during immersion exposure can be improved.

[7] Other additives (G)
The composition of the present invention may contain a carboxylic acid onium salt. Examples of such carboxylic acid onium salts include those described in US Patent Application Publication No. 2008/0187860 <0605> to <0606>.

When the composition of the present invention contains a carboxylic acid onium salt, the content is generally 0.1 to 20% by mass, preferably 0.5 to 10% by mass, based on the total solid content of the composition. %, More preferably 1 to 7% by mass.

Moreover, the composition of this invention may also contain what is called an acid growth agent as needed. The acid proliferating agent is particularly preferably used when performing the pattern forming method of the present invention by EUV exposure or electron beam irradiation. Although it does not specifically limit as a specific example of an acid multiplication agent, For example, the following is mentioned.

In the composition of the present invention, a dye, a plasticizer, a photosensitizer, a light absorber, an alkali-soluble resin, a dissolution inhibitor, and a compound that promotes solubility in a developer (for example, a molecular weight of 1000 or less) A phenol compound, an alicyclic compound having a carboxyl group, or an aliphatic compound).

The composition of the present invention is preferably used in a film thickness of 30 to 250 nm, more preferably in a film thickness of 30 to 200 nm, from the viewpoint of improving resolution.

The solid content concentration of the composition of the present invention is usually 1.0 to 10% by mass, preferably 2.0 to 5.7% by mass, and more preferably 2.0 to 5.3% by mass. By setting the solid content concentration within the above range, the resist solution can be uniformly applied on the substrate.

The solid content concentration is the weight percentage of the weight of other resist components excluding the solvent with respect to the total weight of the chemically amplified resist composition.

The composition of the present invention is used by dissolving the above-described components in a predetermined organic solvent, preferably the mixed solvent, filtering the solution, and applying the solution on a predetermined support (substrate). The pore size of the filter used for filter filtration is preferably 0.1 μm or less, more preferably 0.05 μm or less, and still more preferably 0.03 μm or less made of polytetrafluoroethylene, polyethylene, or nylon. In filter filtration, for example, as in JP-A-2002-62667, circulation filtration may be performed, or filtration may be performed by connecting a plurality of types of filters in series or in parallel. The composition may be filtered multiple times. Furthermore, you may perform a deaeration process etc. with respect to a composition before and behind filter filtration.

The pattern formation method of the present invention can also be suitably used for guide pattern formation in DSA (Directed Self-Assembly) (see, for example, ACS Nano Vol. 4 No. 8, Pages 4815-4823).

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.
<Synthesis Example 1>
Under a nitrogen stream, 40 g of a 6/4 (mass ratio) mixed solvent of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether was placed in a three-necked flask and heated to 80 ° C. (solvent 1). Monomers corresponding to the following repeating units were dissolved in a 6/4 (mass ratio) mixed solvent of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether at a molar ratio of 30/10/60, respectively, and 22 mass% monomer A solution (400 g) was prepared. Further, a solution obtained by adding 8 mol% of a polymerization initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) to the monomer and dissolving it was dropped into the solvent 1 over 6 hours. After completion of dropping, the reaction was further continued at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then poured into 3600 ml of hexane / 400 ml of ethyl acetate, and the deposited precipitate was collected by filtration and dried to obtain 74 g of Resin (P-1). About the obtained resin (P-1), the weight average molecular weight (Mw: polystyrene conversion), the number average molecular weight (Mn: polystyrene conversion), and the dispersity (Mw / Mn) were calculated by GPC (solvent: THF) measurement. . The composition ratio (molar ratio) was calculated by ¹ H-NMR measurement.

Resins (P-2) to (P-10) described later were prepared in the same manner as in Synthesis Example 1 except that the monomers corresponding to each repeating unit were used so as to have a desired composition ratio (molar ratio). And hydrophobic resins (N-1) to (N-3) were synthesized.

<Resist preparation>
The components shown in Table 3 below were dissolved in the solvent shown in the same table to give a total solid content concentration of 3.5% by mass, and each was filtered through a polyethylene filter having a pore size of 0.05 μm to obtain resist compositions Ar-1 to Ar. -15 was prepared.

Abbreviations in Table 3 are as follows.
〔resin〕
The composition ratio (molar ratio), weight average molecular weight and dispersity of the resins used in the examples are shown below.

[Acid generator]
The structural formula of the acid generator is shown below.

[Basic compounds]
The structural formula of the basic compound is shown below.

[Hydrophobic resin]
The composition ratio (molar ratio), weight average molecular weight and degree of dispersion of the hydrophobic resin used in the examples are shown below.

[Surfactant]
W-1: Megafuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based)
W-4: PolyFox PF-6320 (manufactured by OMNOVA) (fluorine-based)
〔solvent〕
A1: Propylene glycol monomethyl ether acetate (PGMEA)
A2: γ-butyrolactone A3: Cyclohexanone B1: Propylene glycol monomethyl ether (PGME)
B2: Ethyl lactate B3: 2-Heptanone B4: Propylene carbonate ・ Alkaline developer preparation Each component was mixed so that the normality was the value shown in Table 4 below, and observed whether the components were completely compatible at 23 ° C. did. The total amount for the completely dissolved level and the total amount of the aqueous phase for the level where the phases were separated were filtered through a polyethylene filter having a pore size of 0.05 μm to prepare alkali developers D-1 to D-11.

[Performance evaluation]
A resist pattern was formed by the following method using the prepared composition.
Example 1
An ARC29A (manufactured by Nissan Chemical Co., Inc.) for forming an organic antireflection film was applied on a silicon wafer having an 8 inch diameter, and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 84 nm. A resist composition Ar-1 was applied thereon and baked at 100 ° C. for 60 seconds to form a resist film having a thickness of 100 nm. The obtained wafer was subjected to an exposure mask (6% HTPSM, line / space = 75 nm) using an ArF excimer laser scanner (PAS5500 / 1100, manufactured by ASML, NA0.75, Dipole, outer sigma 0.89, inner sigma 0.65). / 75 nm), pattern exposure was performed with an exposure amount at which the line width of the line pattern was 112.5 nm. Thereafter, heating is performed at 100 ° C. for 60 seconds, D-1 is paddled for 30 seconds, developed, paddled with pure water for 30 seconds, rinsed, and then the wafer is rotated at 2000 rpm for 30 seconds. After heating and paddle development with butyl acetate for 30 seconds, paddle with MIBC for 30 seconds and rinsing, the wafer is rotated at 2000 rpm for 30 seconds and baked at 90 ° C. for 60 seconds. A resist pattern of 37.5 nm 1: 1 line and space was obtained.

Examples 2 to 10, 12 to 19, Comparative Example 1
1 having a line width of 37.5 nm was obtained in the same manner as in Example 1 except that the resist, the first developer, the first rinse, the second developer, the second rinse and the conditions described in Table 5 were used. 1: A line and space resist pattern was obtained.

Example 11
ARC29SR (Nissan Chemical Co., Ltd.) for forming an organic antireflection film was applied onto a 12-inch diameter silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 95 nm. A resist composition Ar-11 was applied thereon, and baked at 100 ° C. for 60 seconds to form a resist film having a thickness of 100 nm. The obtained wafer was subjected to an exposure mask (6% HTPSM, XT1700i, NA1.20, C-Quad, outer sigma 0.981, inner sigma 0.895, XY deflection manufactured by ASML) using an ArF excimer laser immersion scanner. (Line / space = 65 nm / 65 nm), pattern exposure was performed with an exposure amount at which the line width of the line pattern was 97.5 nm. Ultra pure water was used as the immersion liquid. Thereafter, heating is performed at 100 ° C. for 60 seconds, D-2 is paddled for 30 seconds, developed, paddled with pure water for 30 seconds, rinsed, and then the wafer is rotated at 2000 rpm for 30 seconds. After heating, paddle EEP for 30 seconds, develop, paddle with MIBC for 30 seconds, rinse, rotate the wafer for 30 seconds at 2000 rpm, and bake at 90 ° C. for 60 seconds to obtain a line width of 32 A 5 nm 1: 1 line and space resist pattern was obtained.

Example 20
An ARC29A (manufactured by Nissan Chemical Co., Inc.) for forming an organic antireflection film was applied on a silicon wafer having an 8 inch diameter, and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 84 nm. A resist composition Ar-1 was applied thereon and baked at 100 ° C. for 60 seconds to form a resist film having a thickness of 100 nm. The obtained wafer was subjected to an exposure mask (6% HTPSM, line / space = 75 nm) using an ArF excimer laser scanner (PAS5500 / 1100, manufactured by ASML, NA0.75, Dipole, outer sigma 0.89, inner sigma 0.65). / 75 nm), pattern exposure was performed with an exposure amount at which the line width of the line pattern was 75 nm. Thereafter, heating is performed at 100 ° C. for 60 seconds, D-1 is paddled for 30 seconds, developed, padded with pure water for 30 seconds, rinsed, and then the wafer is rotated at 2000 rpm for 30 seconds, and then at 90 ° C. for 60 seconds. By baking, a 1: 1 line and space resist pattern with a line width of 75 nm was obtained.

Comparative Example 2
A 1: 1 line and space resist pattern having a line width of 75 nm was obtained in the same manner as in Example 20 except that the resist, the first developer, the first rinse solution and the conditions shown in Table 5 were employed.

In Table 5, PB means heating before exposure, and PEB means heating after exposure. Further, in the columns of PB, PEB, first post bake and second post bake, for example, “100 ° C. 60 s” means heating at 100 ° C. for 60 seconds. EEP represents ethyl-3-ethoxypropionate and MIBC represents 4-methyl-2-pentanol.

-Observation of pattern persistence in double development Using AFM (trade name: Nanoscope 4) manufactured by Veeco, the line pattern in the pattern formation region in the wafer of each example was scanned in the longitudinal direction. Table 6 shows the result of calculating the difference between the average height of the pattern top portion and the average height of the pattern bottom portion. The larger the difference, the better the pattern persistence.

-Line width roughness (LWR) observation The line-and-space resist pattern obtained in each example was observed using a length-measuring scanning electron microscope (SEM, Hitachi, Ltd. S-9380II). The line width of the resist pattern was measured by measuring 50 points at equal intervals in the range of 2 μm in the longitudinal direction of the pattern, and calculating 3σ (nm) from the standard deviation. A smaller value indicates better performance.

From the results shown in the above table, it can be seen that the pattern forming method including the alkali developing step using the basic compound-containing aqueous developer of the present invention is superior in roughness characteristics as compared with the comparative example. Furthermore, it can be seen that in the double development including the organic solvent development step, the pattern persistence is also excellent.

Although the embodiments have been described above, the present invention is not limited to these embodiments. For example, patterns can be formed in the following modes (mode X, mode Y, and mode Z).

Aspect X: An aspect in which development is performed by adding about 1% by mass of a nitrogen-containing basic compound such as trioctylamine to the second developer of the above-described embodiment.
Aspect Y (EUV exposure aspect): In the above-mentioned embodiment, the ArF excimer laser exposure is replaced with EUV exposure. Further, as the resin in the resist composition, the above-mentioned “especially EUV exposure or electron beam exposure”. An embodiment using a resin introduced as “resin that can be suitably used in the process”.

Aspect Z: Aspect in which the evaluation in ArF dry exposure (exposure not involving immersion liquid) is changed to the evaluation in ArF immersion exposure among the above-described embodiments.

DESCRIPTION OF SYMBOLS 1 ... Pattern (unexposed part), 2 ... Resin (resin to be protected) of exposed part, 3 ... Basic compound (polyvalent base compound) of this invention, 4 ... Substrate, 11 ... High exposure area (exposure area), 12 ... Intermediate exposure area (intermediate exposure area), 13 ... Low exposure area (unexposed area)

Claims

A step of forming an actinic ray-sensitive or radiation-sensitive film using an actinic ray-sensitive or radiation-sensitive resin composition containing a resin that decomposes by the action of an acid to produce an acidic functional group;
Exposing the actinic ray-sensitive or radiation-sensitive film; and
An alkali development step of developing the exposed actinic ray-sensitive or radiation-sensitive film using an aqueous developer containing a basic compound having two or more basic functional groups,
A pattern forming method including:
The pattern forming method according to claim 1, further comprising an organic development step of developing the actinic ray-sensitive or radiation-sensitive film using a developer containing an organic solvent after the alkali development step.
The pattern forming method according to claim 1 or 2, wherein the basic compound is a compound capable of preparing an aqueous solution having a normality of 0.1 N or more at 23 ° C.
The basic compound according to any one of claims 1 to 3, wherein the basic compound is a compound having at least one selected from a tertiary amino group and a quaternary ammonio group as the basic functional group. Pattern forming method.
The pattern forming method according to claim 4, wherein the basic compound is a compound having at least one quaternary ammonio group as the basic functional group.
The pattern forming method according to any one of claims 1 to 5, wherein the basic compound is a compound having three or more basic functional groups.
Between the exposure step and the alkali development step, between the heating step A for heating the actinic ray-sensitive or radiation-sensitive film after exposure, between the alkali development step and the organic development step, alkali development A heating step B that heats the actinic ray-sensitive or radiation-sensitive film later, and the heating temperature in the heating step B is 30 ° C. or higher than the heating temperature in the heating step A. 2. The pattern forming method according to item 1.
The pattern forming method according to any one of claims 1 to 7, wherein the exposure step is a step of bringing a liquid into contact with the actinic ray-sensitive or radiation-sensitive film and performing exposure through the liquid.
A method for manufacturing an electronic device, comprising the pattern forming method according to any one of claims 1 to 8.
An electronic device manufactured by the method for manufacturing an electronic device according to claim 9.
A step of forming an actinic ray-sensitive or radiation-sensitive film using an actinic ray-sensitive or radiation-sensitive resin composition containing a resin that decomposes by the action of an acid to generate an acidic functional group, the actinic ray-sensitive property Alternatively, an aqueous developer used in a pattern forming method including a step of exposing a radiation-sensitive film and an alkali development step of developing the exposed actinic ray-sensitive or radiation-sensitive film using an aqueous developer. An aqueous developer containing a basic compound having two or more basic functional groups.
The aqueous developer according to claim 11, wherein the basic compound is a compound capable of preparing an aqueous solution having a normality of 0.1 N or more at 23 ° C.
The aqueous developer according to claim 11 or 12, wherein the basic compound is a compound having at least one selected from a tertiary amino group and a quaternary ammonio group as the basic functional group.
The aqueous developer according to claim 13, wherein the basic compound is a compound having at least one quaternary ammonio group as the basic functional group.
The aqueous developer according to any one of claims 11 to 14, wherein the basic compound is a compound having three or more basic functional groups.