WO2016203888A1

WO2016203888A1 - Pattern forming method and electronic device production method

Info

Publication number: WO2016203888A1
Application number: PCT/JP2016/064620
Authority: WO
Inventors: 創古谷; 三千紘白川
Original assignee: 富士フイルム株式会社
Priority date: 2015-06-19
Filing date: 2016-05-17
Publication date: 2016-12-22
Also published as: TW201704872A; JP2018128476A

Abstract

This pattern forming method comprises: a step 1 in which a film is formed upon a substrate by using a actinic ray-sensitive or a radiation-sensitive resin composition containing at least a resin having a group that is decomposed by the action of an acid and generates a polar group; a step 2 in which said film is exposed; a step 3 in which the exposed film is developed and a pattern is formed; and a step 4 in which the pattern is plasma-treated. In step 3, either a developing solution including water is used, the film is developed, and then a developing solution including an organic solvent is used, the film is developed and a pattern is formed or, alternatively, a developing solution including an organic solvent is used, the film is developed and then a developing solution including water is used, the film is developed, and a pattern is formed. The weight-average molecular weight of the resin is at least 5,000. This electronic device production method includes said pattern forming method.

Description

Pattern forming method and electronic device manufacturing method

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 a lithography process for other photo applications, and an electronic device including the pattern forming method. It relates to the manufacturing method.

Since the resist for KrF excimer laser (248 nm), a pattern formation method using chemical amplification has been used to compensate for the sensitivity reduction due to light absorption.
For example, Patent Document 1 proposes a double development technique using a positive developer and a negative developer as a method for stably forming a high-precision fine pattern. More specifically, by utilizing the fact that the polarity of the resin in the resist composition by exposure is high in regions where light intensity is high and low in regions where light intensity is low, a specific resist is used. By dissolving the high exposure area of the film in a developer containing water and dissolving the low exposure area in a developer containing an organic solvent, the intermediate exposure area remains undissolved and removed by development. A line and space pattern having a half pitch is formed.

JP 2008-292975 A

In recent years, higher functionality of various electronic devices has been demanded, and accordingly, further improvement in characteristics of resist patterns used for fine processing has been demanded. In particular, it is required to form a resist pattern having a smaller LWR (Line WidthｎｅRoughness).

In view of the above circumstances, an object of the present invention is to provide a pattern forming method capable of forming a pattern having a small LWR and an electronic device manufacturing method including the pattern forming method.

As a result of intensive studies, the present inventors have found that the above object can be achieved by performing a specific process on the formed pattern, and have completed the present invention.

That is, the present invention provides the following [1] to [7].
[1] Step 1 of forming a film on a substrate using an actinic ray-sensitive or radiation-sensitive resin composition containing at least a resin containing a repeating unit having a group that decomposes by the action of an acid to generate a polar group; , The step 2 for exposing the film, the step 3 for developing the exposed film to form a pattern, and the step 4 for performing a plasma treatment on the pattern, wherein the step 3 includes water. After developing the film using a developer, the film is developed using a developer containing an organic solvent to form a pattern, or after developing using a developer containing an organic solvent, a developer containing water is added. A pattern forming method in which the resin is used to develop a pattern to form a pattern, and the resin has a weight average molecular weight of 5,000 or more.
[2] The pattern forming method according to [1], wherein the step 4 is a step of performing a plasma treatment on the pattern with a plasma generated from a processing gas containing hydrogen.
[3] The pattern forming method according to [2], wherein the processing gas further includes argon.
[4] The pattern forming method according to any one of [1] to [3], wherein the polar group is a carboxyl group.
[5] The resin includes a repeating unit having a group that decomposes by the action of an acid to generate a polar group, and the content of the repeating unit is 35 mol% or more based on all the repeating units of the resin. The pattern forming method according to any one of [1] to [4] above.
[6] Any one of the above [1] to [5], wherein the resin further has at least one structure selected from the group consisting of a lactone structure, a sultone structure, a cyclic ketone structure, and a cyclic sulfone structure. The pattern formation method as described.
[7] A method for manufacturing an electronic device, comprising the pattern forming method according to any one of [1] to [6].

According to the present invention, it is possible to provide a pattern forming method capable of forming a pattern with a small LWR and a method of manufacturing an electronic device including the pattern forming method.

It is sectional drawing which shows roughly an example of the processing apparatus used when performing a plasma processing.

Hereinafter, embodiments of the present invention will be described in detail.
In the description of the group (atomic group) in this specification, the notation which does not describe substitution and non-substitution includes the thing which has a substituent with the thing which does not have a substituent. 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).
In the present specification, “active light” or “radiation” means, for example, the emission line spectrum of a mercury lamp, far ultraviolet rays represented by excimer laser, extreme ultraviolet rays (EUV light), X-rays, electron beams (EB), etc. To do. In the present invention, light means actinic rays or radiation.
In addition, “exposure” in the present specification is not limited to exposure to far ultraviolet rays, extreme ultraviolet rays, X-rays, EUV light and the like represented by mercury lamps and excimer lasers, but also electron beams, ion beams, and the like, unless otherwise specified. The exposure with the particle beam is also included in the exposure.
In the present specification, “to” is used in the sense of including the numerical values described before and after it as a lower limit value and an upper limit value.
In the present specification, “(meth) acrylate” represents acrylate and methacrylate, “(meth) acryl” represents acryl and methacryl, and “(meth) acryloyl” represents acryloyl and methacryloyl.

The pattern forming method of the present invention includes at least the following four steps.
(1) Step of forming a film on a substrate using an actinic ray-sensitive or radiation-sensitive resin composition containing at least a resin having a group that decomposes by the action of an acid to generate a polar group (2) Exposing the film (3) developing the exposed film to form a pattern (4) applying plasma treatment to the pattern In the pattern forming method of the present invention, the step (3) includes developing with water The weight of the resin used in the step (1), in which one of the step A and the step B using the developer containing the organic solvent is performed, and then the other step is performed. The average molecular weight is 5000 or more.
According to such a pattern forming method of the present invention, a pattern (resist pattern) having a small LWR (Line Width Roughness) can be formed. The reason is presumed as follows. That is, the resin in the resist pattern is agglomerated by subjecting the resist pattern formed by development in step (3) to plasma treatment in step (4). At this time, the weight average molecular weight of the resin is 5, By being as large as 000 or more, the resin is more likely to aggregate, and as a result, the sidewall of the resist pattern becomes smooth by plasma treatment, and LWR is considered to be small.
Hereinafter, each process is explained in full detail.

[Step (1): Film formation step]
Step (1) is a step of forming a film (hereinafter also referred to as “resist film”) on a substrate using an actinic ray-sensitive or radiation-sensitive resin composition.
First, the material used at this process is explained in full detail, and the procedure of the subsequent process (1) is explained in full detail.

<Actinic ray-sensitive or radiation-sensitive resin composition>
The pattern forming method of the present invention comprises an actinic ray-sensitive or radiation-sensitive resin composition (hereinafter referred to as “composition” or “resist” containing a resin (A) having a group that decomposes by the action of an acid to generate a polar group. Also referred to as “film-forming composition”).
Below, the composition used by this invention is demonstrated.
First, the resin (A) having a group that generates a polar group by being decomposed by the action of an acid contained in the composition, and other optional components will be described in detail.

[1] Resin (A) having a group that decomposes by the action of an acid to generate a polar group (hereinafter, also simply referred to as “resin (A)”)
Resin (A) having a group capable of decomposing by the action of an acid to generate a polar group is decomposed by the action of an acid to produce a polar group in the main chain or side chain of the resin or both of the main chain and the side chain. And a resin having a group (hereinafter also referred to as “acid-decomposable group”) (hereinafter also referred to as “acid-decomposable resin” or “resin (A)”).
The resin (A) is preferably a resin containing a repeating unit having a group that decomposes by the action of an acid to generate a polar group.
The acid-decomposable group preferably has a structure in which a polar group is protected by a group that decomposes and leaves under the action of an acid.
The polar group is not particularly limited as long as it is a group that is hardly soluble or insoluble in a developer containing an organic solvent. , Sulfonamide group, sulfonylimide group, (alkylsulfonyl) (alkylcarbonyl) methylene group, (alkylsulfonyl) (alkylcarbonyl) imide group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkyl Sulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris (alkylsulfonyl) methylene group and other acidic groups (2.38 mass% tetra, conventionally used as a resist developer) Methylan Group dissociates in onium hydroxide aqueous solution), or alcoholic hydroxyl group.

The alcoholic hydroxyl group is a hydroxyl group bonded to a hydrocarbon group and means a hydroxyl group other than a hydroxyl group directly bonded on an aromatic ring (phenolic hydroxyl group). An aliphatic alcohol substituted with a functional group (for example, a fluorinated alcohol group (such as a hexafluoroisopropanol group)) is excluded. The alcoholic hydroxyl group is preferably a hydroxyl group having a pKa of 12 or more and 20 or less.
Preferable polar groups include a carboxyl group, a fluorinated alcohol group (preferably hexafluoroisopropanol group), and a sulfonic acid group, and a carboxyl group is more preferable because the effect of the present invention is more excellent.
A preferable 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 capable of 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, R ₃₆ to R ₃₉ each independently represents an alkyl group, a cycloalkyl group, 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, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group.

The alkyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an alkyl group having 1 to 8 carbon atoms, for example, methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, hexyl Group, octyl group and the like.
The cycloalkyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ may be monocyclic or polycyclic. The monocyclic type is preferably a cycloalkyl group having 3 to 8 carbon atoms, and the polycyclic type is preferably a cycloalkyl group having 6 to 20 carbon atoms. Note that at least one carbon atom in the cycloalkyl group may be substituted with a heteroatom such as an oxygen atom.
The aryl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group.
The aralkyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an aralkyl group having 7 to 12 carbon atoms.
The alkenyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an alkenyl group having 2 to 8 carbon atoms.
The ring formed by combining R ₃₆ and R ₃₇ is preferably a cycloalkyl group (monocyclic or polycyclic). 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. A monocyclic cycloalkyl group having 5 to 6 carbon atoms is more preferable, and a monocyclic cycloalkyl group having 5 carbon atoms is particularly preferable.

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.

The resin (A) preferably contains a repeating unit having an acid-decomposable group.
The repeating unit having an acid-decomposable group is preferably a repeating unit represented by the following general formula (AI). The repeating unit represented by the general formula (AI) generates a carboxyl group as a polar group by the action of an acid.

In general formula (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.

Examples of the divalent linking group for 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 is preferably a divalent linking group in that the effect of the present invention is more excellent. When T is a divalent linking group, the mobility of the polar group generated by the action of an acid is improved, and the effect of the present invention is further improved because it easily interacts with an additive described later.
The divalent linking group is preferably a —COO—Rt— group. 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.

The alkyl group of Xa ₁ may have a substituent, and examples of the substituent include a hydroxyl group and a halogen atom (preferably a fluorine atom).
The alkyl group of Xa ₁ preferably has 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, and a trifluoromethyl group, and a methyl group is preferable.
Xa ₁ is preferably a hydrogen atom or a methyl group.

The alkyl group of Rx ₁ , Rx ₂ and Rx ₃ may be linear or branched, and is a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl. And those having 1 to 4 carbon atoms such as t-butyl group are preferred.
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 the 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, More preferably, it is not an alkyl group substituted with a hydroxyl group, etc.), more preferably a group consisting of only a hydrogen atom and a carbon atom, and particularly preferably a linear or branched alkyl group or a cycloalkyl group. .

Specific examples of the repeating unit represented by formula (AI) are given below, but the present invention is not limited to these specific examples.
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 the specific examples and preferred examples of the substituent that each group such as Rx ₁ to Rx ₃ may have.

One type of repeating unit having an acid-decomposable group may be used, or two or more types may be used in combination. When two types are used in combination, a preferable combination is a combination whose structure is exemplified after paragraph <0121> of US Patent Application Publication No. 2012/0009522 (Note that US Patent Application Publication No. 2012/0009 / No. 0009522 is incorporated herein).

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), For example, it is 20 mol% or more, and from the reason that the effect of the present invention is more excellent, it is preferably 35 mol% or more, and more preferably 40 mol% or more.
Although an upper limit is not specifically limited, For example, it is 80 mol% or less, 70 mol% or less is preferable and 65 mol% or less is more preferable.

Such a resin (A) may further have a structure such as a lactone structure, a sultone structure, a cyclic ketone structure, a cyclic sulfone structure, and a cyclic ether structure.
The lactone structure and sultone structure will be described later.
Here, the cyclic ketone structure means a cyclic ketone structure excluding a lactone structure, and examples thereof include cyclobutanone, cyclopentanone, cyclohexanone, cycloheptanone, and cyclooctanone.
The cyclic sulfone structure means a cyclic sulfone structure excluding a sultone structure, and examples thereof include sulfolane.
The cyclic ether structure means a cyclic ether structure excluding a lactone structure, and examples thereof include a cyclic ether structure having 2 to 6 carbon atoms in the cyclic portion. Specific examples thereof include an oxirane ring, an oxetane ring, Dioxetane rings such as 1,3-dioxetane ring; Dioxolane rings such as tetrahydrofuran ring and 1,3-dioxolane ring; Dioxane rings such as tetrahydropyran ring, 1,3-dioxane ring and 1,4-dioxane ring; Oxepan ring, 1 And dioxepane rings such as 1,3-dioxepane ring and 1,4-dioxepane ring.

The resin (A) preferably has at least one structure selected from the group consisting of a lactone structure, a sultone structure, a cyclic ketone structure, and a cyclic sulfone structure, and a lactone structure, a sultone structure, a cyclic ketone structure, and More preferably, it contains a repeating unit having at least one structure selected from the group consisting of cyclic sulfone structures. Thereby, the effect of this invention is more excellent.

Any lactone structure or sultone structure can be used as long as it has a lactone structure or sultone structure, but a 5- to 7-membered ring lactone structure or a 5- to 7-membered ring sultone structure is preferable. Other ring structures are condensed in a form that forms a bicyclo structure or spiro structure in a membered lactone structure, or other rings that form a bicyclo structure or a spiro structure in a 5- to 7-membered ring sultone structure Those having a condensed ring structure are more preferable. A lactone structure represented by any of the following general formulas (LC1-1) to (LC1-21), or a sultone structure represented by any of the following general formulas (SL1-1) to (SL1-3), More preferably, it has a repeating unit having A lactone structure or a sultone structure may be directly bonded to the main chain. Preferred lactone structures are (LC1-1), (LC1-4), (LC1-5), (LC1-6), (LC1-13), (LC1-14), (LC1-17), especially A preferred lactone structure is (LC1-4).

The lactone structure part or sultone structure part may or may not have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, and a carboxyl group. , Halogen atom, hydroxyl group, cyano group, acid-decomposable group and the like. More preferred are an alkyl group having 1 to 4 carbon atoms, a cyano group, and an acid-decomposable group. n ₂ represents an integer of 0 to 4. When n ₂ is 2 or more, a plurality of substituents (Rb ₂ ) may be the same or different. A plurality of substituents (Rb ₂ ) may be bonded to form a ring.

The repeating unit having a lactone structure or a sultone structure usually has an optical isomer, but any optical isomer may be used. One optical isomer may be used alone, or a plurality of optical isomers may be mixed and used. When one kind of optical isomer is mainly used, the optical purity (ee) thereof is preferably 90% or more, more preferably 95% or more.

The repeating unit having a lactone structure or a sultone structure is preferably a repeating unit represented by the following general formula (III).

In the general formula (III),
A represents an ester bond (a group represented by —COO—) or an amide bond (a group represented by —CONH—).
R ₀ independently represents an alkylene group, a cycloalkylene group, or a combination of two or more of them when there are a plurality of R ₀ .
Z is independently a single bond, an ether bond, an ester bond, an amide bond, or a urethane bond when there are a plurality of Zs.

Or urea bond

Represents. Here, each R independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group.
R ₈ represents a monovalent organic group having a lactone structure or a sultone structure.
n is the number of repetitions of the structure represented by —R ₀ —Z—, and represents an integer of 0 to 5, preferably 0 or 1, and more preferably 0. When n is 0, —R ₀ —Z— does not exist and becomes a single bond.

The preferred chain alkylene group for R ₀ is preferably a chain alkylene group having 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and examples thereof include a methylene group, an ethylene group, and a propylene group. . A preferred cycloalkylene group is a cycloalkylene group having 3 to 20 carbon atoms, and examples thereof include a cyclohexylene group, a cyclopentylene group, a norbornylene group, and an adamantylene group. In order to exhibit the effect of the present invention, a chain alkylene group is more preferable, and a methylene group is particularly preferable.
Z is preferably an ether bond or an ester bond, and particularly preferably an ester bond.

R ₇ represents a hydrogen atom, a halogen atom or an alkyl group.
The alkyl group for R ₇ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group.
R ₇ is preferably a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

Alkylene group R _0, the alkyl group in a cycloalkylene group and R _7, may be respectively substituted, the substituent, for example, a halogen atom (e.g., fluorine atom, chlorine atom, bromine atom), a mercapto Group, hydroxyl group, alkoxy group, acyloxy group and the like.

The monovalent organic group having a lactone structure or a sultone structure represented by R ₈ is not limited as long as it has a lactone structure or a sultone structure. Specific examples include those represented by the general formulas (LC1-1) to (LC1-21). And a lactone structure or a sultone structure represented by any one of (SL1-1) to (SL1-3), and a structure represented by (LC1-4) is particularly preferable. Further, n ₂ in (LC1-1) to (LC1-21) is more preferably 2 or less.
R ₈ is preferably a monovalent organic group having an unsubstituted lactone structure or sultone structure, or a monovalent organic group having a lactone structure or sultone structure having a methyl group, a cyano group or an alkoxycarbonyl group as a substituent. A monovalent organic group having a lactone structure (cyanolactone) having a cyano group as a substituent is more preferable.

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.

In order to enhance the effect of the present invention, 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.

The resin (A) may have a repeating unit having a hydroxyl group or a cyano group. This improves the substrate adhesion and developer compatibility. The repeating unit having a hydroxyl group or a cyano group is preferably a repeating unit having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group, and preferably has no acid-decomposable group.
In addition, the repeating unit having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group is preferably different from the repeating unit having an acid-decomposable group (that is, it is a stable repeating unit with respect to an acid). preferable).
The alicyclic hydrocarbon structure in the alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group is preferably an adamantyl group, a diamantyl group, or a norbornane group.
More preferred examples include repeating units represented by any of the following general formulas (AIIa) to (AIIc).

In the formula, Rx represents a hydrogen atom, a methyl group, a hydroxymethyl group, or a trifluoromethyl group.
Ab represents a single bond or a divalent linking group.
Examples of the divalent linking group represented by Ab include an alkylene group, a cycloalkylene group, an ester bond, an amide bond, an ether bond, a urethane bond, a urea bond, or a combination of two or more thereof. The alkylene group is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 5 carbon atoms, and examples thereof include a methylene group, an ethylene group, and a propylene group.
In one embodiment of the present invention, Ab is preferably a single bond or an alkylene group.
Rp represents a hydrogen atom, a hydroxyl group, or a hydroxyalkyl group. The plurality of Rp may be the same or different, but at least one of the plurality of Rp represents a hydroxyl group or a hydroxyalkyl group.

The resin (A) may or may not contain a repeating unit having a hydroxyl group or a cyano group, but when the resin (A) contains a repeating unit having a hydroxyl group or a cyano group, The content of the repeating unit having a cyano group is preferably 1 to 40 mol%, more preferably 3 to 30 mol%, still more preferably 5 to 25 mol%, based on all repeating units in the resin (A). . The resin (A) may contain two or more types of repeating units having a hydroxyl group or a cyano group having different structures.

Specific examples of the repeating unit having a hydroxyl group or a cyano group are listed below, but the present invention is not limited thereto.

The resin (A) in the present invention may further have a repeating unit that has an alicyclic hydrocarbon 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. . As a result, the elution of low molecular components from the resist film to the immersion liquid during immersion exposure can be reduced, and the solubility of the resin can be appropriately adjusted during development using a developer containing an organic solvent. . Examples of such a repeating unit include a repeating unit represented by the general formula (IV).

In general formula (IV), R ₅ represents a hydrocarbon group having at least one cyclic structure and having no polar group.
Ra represents a hydrogen atom, an alkyl group, or a —CH ₂ —O—Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group. Ra is preferably a hydrogen atom, a methyl group, a hydroxymethyl group or a trifluoromethyl group, particularly preferably a hydrogen atom or a methyl group.

The cyclic structure possessed by R ₅ includes a monocyclic hydrocarbon group and a polycyclic hydrocarbon group. As the monocyclic hydrocarbon group, a cyclopentyl group and a cyclohexyl group are preferable.

The polycyclic hydrocarbon group includes a ring assembly hydrocarbon group and a bridged cyclic hydrocarbon group, and examples of the ring assembly hydrocarbon group include a bicyclohexyl group and a perhydronaphthalenyl group. As the bridged cyclic hydrocarbon ring, for example, bicyclic such as pinane, bornane, norpinane, norbornane, bicyclooctane ring (bicyclo [2.2.2] octane ring, bicyclo [3.2.1] octane ring, etc.) Hydrocarbon rings and tricyclic hydrocarbon rings such as homobredan, adamantane, tricyclo [5.2.1.0 ^2,6 ] decane, tricyclo [4.3.1.1 ^2,5 ] undecane ring, tetracyclo [ 4.4.0.1 ^2,5 . 1 ^7,10 ] dodecane, and tetracyclic hydrocarbon rings such as perhydro-1,4-methano-5,8-methanonaphthalene ring. The bridged cyclic hydrocarbon ring includes a condensed cyclic hydrocarbon ring such as perhydronaphthalene (decalin), perhydroanthracene, perhydrophenanthrene, perhydroacenaphthene, perhydrofluorene, perhydroindene, perhydroindene. A condensed ring formed by condensing a plurality of 5- to 8-membered cycloalkane rings such as a phenalene ring is also included.

Preferred examples of the bridged cyclic hydrocarbon ring include a norbornyl group, an adamantyl group, a bicyclooctanyl group, a tricyclo [5,2,1,0 ^2,6 ] decanyl group, and the like. More preferable examples of the bridged cyclic hydrocarbon ring include a norbornyl group and an adamantyl group.

These alicyclic hydrocarbon groups may have a substituent. Preferred examples of the substituent include a halogen atom, an alkyl group, a hydroxyl group substituted with a hydrogen atom, and an amino group substituted with a hydrogen atom. It is done. Moreover, you may have hetero atoms, such as an oxygen atom.

The resin (A) has an alicyclic hydrocarbon structure having no polar group, and may or may not contain a repeating unit that does not exhibit acid decomposability. The content is preferably 1 to 50 mol%, more preferably 5 to 50 mol%, still more preferably 5 to 30 mol%, based on all repeating units in the resin (A). In addition, resin (A) may contain the repeating unit which has two or more types of alicyclic hydrocarbon structures which do not have a polar group, and which does not show acid-decomposability | different_conditions from which a structure differs.
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 .

The resin (A) used in the composition is a general component of dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and actinic ray sensitive or radiation sensitive resin composition in addition to the above repeating structural units. It is possible to have various repeating structural units for the purpose of adjusting resolving power, heat resistance, sensitivity, and the like, which are necessary characteristics.

Examples of such repeating structural units include, but are not limited to, repeating structural units corresponding to the following monomers.

Thereby, performance required for the resin used in the actinic ray-sensitive or radiation-sensitive resin composition, in particular,
(1) Solubility in coating solvent,
(2) Film formability (glass transition point),
(3) Alkali developability,
(4) Membrane slip (hydrophobic, alkali-soluble group selection),
(5) Adhesion of unexposed part to substrate,
(6) Fine adjustment such as dry etching resistance can be performed.

As such a monomer, for example, a compound having one addition polymerizable unsaturated bond selected from acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, etc. Etc.

In addition, any addition-polymerizable unsaturated compound that can be copolymerized with monomers corresponding to the above various repeating structural units may be copolymerized.

In the resin (A) used in the actinic ray-sensitive or radiation-sensitive resin composition, the content molar ratio of each repeating structural unit is the dry etching resistance of the actinic ray-sensitive or radiation-sensitive resin composition, suitability for a standard developer, It is suitably set to adjust the substrate adhesion, resist profile, and further the resolving power, heat resistance, sensitivity, etc., which are general required performances of the actinic ray-sensitive or radiation-sensitive resin composition.

The form of the resin (A) 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 actinic ray-sensitive or radiation-sensitive resin composition is for ArF exposure, the resin (A) has substantially no aromatic ring from the viewpoint of transparency to ArF light (specifically, In the resin, the ratio of the repeating unit having an aromatic group is preferably 5 mol% or less, more preferably 3 mol% or less, ideally 0 mol%, that is, it preferably has no aromatic group). The resin (A) preferably has a monocyclic or polycyclic alicyclic hydrocarbon structure.
In the case where the actinic ray-sensitive or radiation-sensitive resin composition contains a hydrophobic resin (D) described later, the resin (A) is a fluorine atom and a fluorine atom from the viewpoint of compatibility with the hydrophobic resin (D). Does not contain silicon atoms (specifically, the proportion of repeating units containing fluorine atoms or silicon atoms in the resin is preferably 5 mol% or less, more preferably 3 mol% or less, ideally 0 mol%) It is preferable.

The resin (A) used in the actinic ray-sensitive or radiation-sensitive resin composition is preferably one in which all of the repeating units are composed of (meth) acrylate 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 actinic ray-sensitive or radiation-sensitive resin composition 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) is further fragrant. It is preferable to have a repeating unit containing a ring structure, for example, a hydroxystyrene-based repeating unit. More preferably, it has a hydroxystyrene-based repeating unit, a hydroxystyrene-based repeating unit protected with an acid-decomposable group, and an acid-decomposable repeating unit such as a (meth) acrylic acid tertiary alkyl ester.

Examples of the repeating unit having a preferable acid-decomposable group based on hydroxystyrene include, for example, a repeating unit of t-butoxycarbonyloxystyrene, 1-alkoxyethoxystyrene, (meth) acrylic acid tertiary alkyl ester, and the like. More preferred are repeating units of 2-alkyl-2-adamantyl (meth) acrylate and dialkyl (1-adamantyl) methyl (meth) acrylate.

Specific examples of the resin having a repeating unit containing an aromatic ring structure include, for example, resins described in paragraphs <0104> to <0108> of JP-A-2014-232310.

The resin (A) in the present invention can be synthesized according to a conventional method (for example, radical polymerization, living radical polymerization, anion polymerization). For example, reference can be made to the descriptions in paragraphs <0121> to <0128> of JP2012-073402 (corresponding to paragraphs <0203> to <0211> of the corresponding US Patent Application Publication No. 2012/0777122). The contents are incorporated herein.

The weight average molecular weight (Mw) of the resin (A) in the present invention is 5,000 or more as described above, and is preferably 7,000 or more, more preferably 12,000 or more because the effect of the present invention is more excellent. More preferably, 17,000 or more is even more preferable.
In addition, although the upper limit of the weight average molecular weight (Mw) of resin (A) is not specifically limited, For example, it is 200,000 or less, 100,000 or less are preferable and 50,000 or less are more preferable.

The dispersity (molecular weight distribution), which is the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn), is usually 1.0 to 3.0, for example, preferably 1.0 to Those having a range of 2.6, more preferably 1.0 to 2.0, particularly preferably 1.4 to 2.0 are used. The smaller the molecular weight distribution, the better the resolution and the resist shape, and the smoother the sidewall of the resist pattern, the better the roughness.

In the present invention, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are converted to polystyrene using a gel permeation chromatography (GPC) method using tetrahydrofuran (THF) as a developing solvent. Value.
More specifically, the weight average molecular weight (Mw) and number average molecular weight (Mn) are measured using GPC under the following conditions.
Column type: TSK gel Multipore HXL-M (manufactured by Tosoh Corporation, 7.8 mm ID × 30.0 cm)
・ Developing solvent: THF (tetrahydrofuran)
-Column temperature: 40 ° C
・ Flow rate: 1 mL / min
Sample injection volume: 10 μL
・ Device name: HLC-8120 (manufactured by Tosoh Corporation)

In the actinic ray-sensitive or radiation-sensitive resin composition, the blending ratio of the resin (A) in the whole 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.

[2] Compound (B) that generates an acid upon irradiation with an actinic ray or radiation
The actinic ray-sensitive or radiation-sensitive resin composition used in the present invention is usually a compound (B) that generates an acid upon irradiation with actinic rays or radiation (hereinafter referred to as “acid generator” “compound (B ) ”)). The compound (B) that generates an acid upon irradiation with actinic rays or radiation is preferably a compound that generates an organic acid upon irradiation with actinic rays or radiation. In addition, the compound (B) may be contained in the resin (A) described above. More specifically, the compound (B) may be linked to the resin (A) via a chemical bond.
The compound (B) that generates an acid upon irradiation with actinic rays or radiation may be in the form of a low molecular compound or may be incorporated in a part of the polymer. Moreover, you may use together the form incorporated in a part of polymer and the form of a low molecular compound.
When the compound (B) that generates an acid upon irradiation with actinic rays or radiation is in the form of a low molecular compound, the molecular weight is preferably 3000 or less, more preferably 2000 or less, and 1000 or less. Is more preferable.
When the compound (B) that generates an acid upon irradiation with actinic rays or radiation is in a form incorporated in a part of the polymer, it may be incorporated in a part of the acid-decomposable resin described above, and is acid-decomposable. It may be incorporated in a resin different from the resin.
In the present invention, the compound (B) that generates an acid upon irradiation with actinic rays or radiation is preferably in the form of a low molecular compound.
As the acid generator, photo-initiator of photocation polymerization, photo-initiator of photo-radical polymerization, photo-decoloring agent of dyes, photo-discoloring agent, irradiation of actinic ray or radiation used for micro resist, etc. The known compounds that generate an acid and mixtures thereof can be appropriately selected and used.

For example, examples of the acid generator include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, imide sulfonates, oxime sulfonates, diazodisulfones, disulfones, and o-nitrobenzyl sulfonates.

Preferred compounds among the acid generators include compounds represented by the following general formulas (ZI), (ZII), and (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.
Further, two members out of R ₂₀₁ to R ₂₀₃ may combine 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 of R ₂₀₁ to R ₂₀₃ include an alkylene group (eg, butylene group, pentylene group).
Z ⁻ represents a non-nucleophilic anion.

Examples of the non-nucleophilic anion as Z ⁻ include a sulfonate anion, a carboxylate anion, a sulfonylimide anion, a bis (alkylsulfonyl) imide anion, and a tris (alkylsulfonyl) methyl anion.

A non-nucleophilic anion is an anion having a remarkably low ability to cause a nucleophilic reaction, and an anion capable of suppressing degradation with time due to an intramolecular nucleophilic reaction. Thereby, the temporal stability of the actinic ray-sensitive or radiation-sensitive resin composition is improved.

Examples of the sulfonate anion include an aliphatic sulfonate anion, an aromatic sulfonate anion, and a camphor sulfonate anion.
Examples of the carboxylate anion include an aliphatic carboxylate anion, an aromatic carboxylate anion, and an aralkylcarboxylate anion.

The aliphatic moiety in the aliphatic sulfonate anion and the aliphatic carboxylate anion may be an alkyl group or a cycloalkyl group, preferably an alkyl group having 1 to 30 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms. Alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl , Undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, norbornyl group, bornyl group, etc. Can be mentioned.

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 in the aliphatic sulfonate anion and aromatic sulfonate anion may have a substituent. Examples of the substituent of the alkyl group, cycloalkyl group, and aryl group in the aliphatic sulfonate anion and aromatic sulfonate anion include, for example, a nitro group, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), carboxyl group Hydroxyl group, amino group, cyano group, alkoxy group (preferably having 1 to 15 carbon atoms), cycloalkyl group (preferably having 3 to 15 carbon atoms), aryl group (preferably having 6 to 14 carbon atoms), alkoxycarbonyl group ( Preferably 2 to 7 carbon atoms, acyl group (preferably 2 to 12 carbon atoms), alkoxycarbonyloxy group (preferably 2 to 7 carbon atoms), alkylthio group (preferably 1 to 15 carbon atoms), alkylsulfonyl group (Preferably having 1 to 15 carbon atoms), alkyliminosulfonyl group (preferably having 1 to 15 carbon atoms), ant Ruoxysulfonyl group (preferably having 6 to 20 carbon atoms), alkylaryloxysulfonyl group (preferably having 7 to 20 carbon atoms), cycloalkylaryloxysulfonyl group (preferably having 10 to 20 carbon atoms), alkyloxyalkyloxy group (Preferably having 5 to 20 carbon atoms), a cycloalkylalkyloxyalkyloxy group (preferably having 8 to 20 carbon atoms), and the like. Regarding the aryl group and ring structure of each group, examples of the substituent further include an alkyl group (preferably having 1 to 15 carbon atoms) and a cycloalkyl group (preferably having 3 to 15 carbon atoms).

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.

The alkyl group, cycloalkyl group, aryl group and aralkyl group in the aliphatic carboxylate anion, aromatic carboxylate anion and aralkylcarboxylate anion may have a substituent. Examples of this substituent include the same halogen atom, alkyl group, cycloalkyl group, alkoxy group, alkylthio group and the like as those in the aromatic sulfonate anion.

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, such as a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl. Group, sec-butyl group, pentyl group, neopentyl group and the like.
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 alkylene group formed by linking two alkyl groups in these alkyl groups and bis (alkylsulfonyl) imide anions may have a halogen atom, an alkyl group substituted with a halogen atom, an alkoxy group, an alkylthio group. , An alkyloxysulfonyl group, an aryloxysulfonyl group, a cycloalkylaryloxysulfonyl group, and the like, and an alkyl group substituted with a fluorine atom is preferred.
Examples of other non-nucleophilic anions include fluorinated phosphorus (for example, PF ₆ ⁻ ), fluorinated boron (for example, BF ₄ ⁻ ), fluorinated antimony (for example, SbF ₆ ⁻ ), and the like. .

As the non-nucleophilic anion of Z ⁻ , an aliphatic sulfonate anion in which at least α position of the sulfonic acid is substituted with a fluorine atom, an aromatic sulfonate anion substituted with a fluorine atom or a group having a fluorine atom, an alkyl group Is preferably a bis (alkylsulfonyl) imide anion substituted with a fluorine atom, or a tris (alkylsulfonyl) methide anion wherein an alkyl group is substituted with a fluorine atom. The non-nucleophilic anion is more preferably a perfluoroaliphatic sulfonate anion having 4 to 8 carbon atoms, a benzenesulfonate anion having a fluorine atom, still more preferably a nonafluorobutanesulfonate anion, a perfluorooctanesulfonate anion, Pentafluorobenzenesulfonate anion, 3,5-bis (trifluoromethyl) benzenesulfonate anion.

The acid generator is preferably a compound that generates an acid represented by the following general formula (V) or (VI) upon irradiation with actinic rays or radiation. Since it is a compound that generates an acid represented by the following general formula (V) or (VI) and has a cyclic organic group, the resolution and roughness performance can be further improved.
As said non-nucleophilic anion, it can be set as the anion which produces the organic acid represented by the following general formula (V) or (VI).

In the above general formula,
Xf each independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom.
R ₁₁ and R ₁₂ each independently represent a hydrogen atom, a fluorine atom, or an alkyl group.
L each independently represents a divalent linking group.
Cy represents a cyclic organic group.
Rf is a group containing a fluorine atom.
x represents an integer of 1 to 20.
y represents an integer of 0 to 10.
z represents an integer of 0 to 10.

Xf represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms. The alkyl group substituted with at least one fluorine atom is preferably a perfluoroalkyl group.
Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms. Xf is more preferably a fluorine atom or CF ₃ . In particular, it is preferable that both Xf are fluorine atoms.

R ₁₁ and R ₁₂ are each independently a hydrogen atom, a fluorine atom, or an alkyl group. This alkyl group may have a substituent (preferably a fluorine atom), and preferably has 1 to 4 carbon atoms. More preferred is a perfluoroalkyl group having 1 to 4 carbon atoms. The alkyl group having a substituent for R ₁₁ and R ₁₂ is preferably CF ₃ .

L represents a divalent linking group. Examples of the divalent linking group include —COO—, —OCO—, —CONH—, —NHCO—, —CO—, —O—, —S—, —SO—, —SO ₂ —, an alkylene group, and the like. (Preferably having 1 to 6 carbon atoms), cycloalkylene group (preferably having 3 to 10 carbon atoms), alkenylene group (preferably having 2 to 6 carbon atoms) or a divalent linking group in which two or more of these are combined. It is done. Among these, —COO—, —OCO—, —CONH—, —NHCO—, —CO—, —O—, —SO ₂ —, —COO-alkylene group—, —OCO-alkylene group—, —CONH— alkylene group - or -NHCO- alkylene group - are preferred, -COO -, - OCO -, - CONH -, - SO 2 -, - COO- alkylene group - or -OCO- alkylene group - is more preferable.

Cy represents a cyclic organic group. Examples of the cyclic organic group include an alicyclic group, an aryl group, and a heterocyclic group.
The alicyclic group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic group include monocyclic cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic group include alicyclic groups having a bulky structure of 7 or more carbon atoms such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. From the viewpoint of suppressing diffusibility in the film in the PEB (post-exposure heating) step and improving MEEF (Mask Error Enhancement Factor).

The aryl group 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 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 furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a pyridine ring. Examples of the heterocyclic ring not having aromaticity include a tetrahydropyran ring, a lactone ring or a sultone ring, and a decahydroisoquinoline ring. As the heterocyclic ring in the heterocyclic group, a furan ring, a thiophene ring, a pyridine ring, or a decahydroisoquinoline ring is particularly preferable. Examples of the lactone ring or sultone ring include the lactone structure or sultone exemplified in the aforementioned resin (A).

The cyclic organic group may have a substituent. Examples of this substituent include an alkyl group (which may be linear or branched, preferably 1 to 12 carbon atoms), and a cycloalkyl group (monocyclic, polycyclic or spirocyclic). Well, preferably having 3 to 20 carbon atoms), aryl group (preferably having 6 to 14 carbon atoms), hydroxyl group, alkoxy group, ester group, amide group, urethane group, ureido group, thioether group, sulfonamide group, and sulfonic acid An ester group is mentioned. The carbon constituting the cyclic organic group (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. z is preferably 0 to 8, more preferably 0 to 4.
Examples of the group containing a fluorine atom represented by Rf include an alkyl group having at least one fluorine atom, a cycloalkyl group having at least one fluorine atom, and an aryl group having at least one fluorine atom. .
These alkyl group, cycloalkyl group and aryl group may be substituted with a fluorine atom, or may be substituted with another substituent containing a fluorine atom. When Rf is a cycloalkyl group having at least one fluorine atom or an aryl group having at least one fluorine atom, other substituents containing a fluorine atom include, for example, alkyl substituted with at least one fluorine atom. Groups.
Further, these alkyl group, cycloalkyl group and aryl group may be further substituted with a substituent not containing a fluorine atom. As this substituent, the thing which does not contain a fluorine atom among what was demonstrated about Cy previously can be mentioned, for example.
Examples of the alkyl group having at least one fluorine atom represented by Rf include those described above as the alkyl group substituted with at least one fluorine atom represented by Xf. Examples of the cycloalkyl group having at least one fluorine atom represented by Rf include a perfluorocyclopentyl group and a perfluorocyclohexyl group. Examples of the aryl group having at least one fluorine atom represented by Rf include a perfluorophenyl group.

Further preferred examples of the (ZI) component include compounds (ZI-1), (ZI-2), (ZI-3) and (ZI-4) described below.

The compound (ZI-1) will be described.
Compound (ZI-1) is an arylsulfonium compound in which at least one of R ₂₀₁ to R ₂₀₃ in formula (ZI) is an aryl group, that is, a compound having arylsulfonium as a cation.

In the arylsulfonium compound, all of R ₂₀₁ to R ₂₀₃ may be an aryl group, or a part of R ₂₀₁ to R ₂₀₃ may be an aryl group with the remaining being an alkyl group or a cycloalkyl group.

Examples of the arylsulfonium compound include a triarylsulfonium compound, a diarylalkylsulfonium compound, an aryldialkylsulfonium compound, a diarylcycloalkylsulfonium compound, and an aryldicycloalkylsulfonium compound.

The aryl group of the arylsulfonium compound is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. The aryl group may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the heterocyclic structure include a pyrrole residue, a furan residue, a thiophene residue, an indole residue, a benzofuran residue, and a benzothiophene residue. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.

The alkyl group or cycloalkyl group optionally possessed by the arylsulfonium compound is preferably a linear or branched alkyl group having 1 to 15 carbon atoms and a cycloalkyl group having 3 to 15 carbon atoms, such as a methyl group, Examples include an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, a cyclopropyl group, a cyclobutyl group, and a cyclohexyl group.

The aryl group, alkyl group, and cycloalkyl group of R ₂₀₁ to R ₂₀₃ are an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), an aryl group (for example, 6 to 14 carbon atoms). , An alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, and a phenylthio group may be substituted. Preferred substituents are linear or branched alkyl groups having 1 to 12 carbon atoms, cycloalkyl groups having 3 to 12 carbon atoms, and linear, branched or cyclic alkoxy groups having 1 to 12 carbon atoms, more preferably carbon atoms. An alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms. The substituent may be substituted with any one of the three R ₂₀₁ to R ₂₀₃ , or may be substituted with all three. Further, when R ₂₀₁ to R ₂₀₃ are an aryl group, the substituent is preferably substituted at the p-position of the aryl group.

Next, the compound (ZI-2) will be described.
Compound (ZI-2) is a compound in which R ₂₀₁ to R ₂₀₃ in formula (ZI) each independently represents an organic group having no aromatic ring. Here, the aromatic ring includes an aromatic ring containing a hetero atom.

The organic group not containing an aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms.

R ₂₀₁ to R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear or branched 2-oxoalkyl group, 2-oxocycloalkyl group, alkoxy group. A carbonylmethyl group, particularly preferably a linear or branched 2-oxoalkyl group.

As the alkyl group and cycloalkyl group represented by R ₂₀₁ to R ₂₀₃ , a linear or branched alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups having a number of 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group). More preferred examples of the alkyl group include a 2-oxoalkyl group and an alkoxycarbonylmethyl group. More preferred examples of the cycloalkyl group include a 2-oxocycloalkyl group.

The 2-oxoalkyl group may be linear or branched, and a group having> C═O at the 2-position of the above alkyl group is preferable.
The 2-oxocycloalkyl group is preferably a group having> C═O at the 2-position of the above cycloalkyl group.

The alkoxy group in the alkoxycarbonylmethyl group is preferably an alkoxy group having 1 to 5 carbon atoms (methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group).

R ₂₀₁ to R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (eg, having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

Next, the compound (ZI-3) will be described.
The compound (ZI-3) is a compound represented by the following general formula (ZI-3), and is a compound having a phenacylsulfonium salt structure.

In general formula (ZI-3),
R _1c to R _5c are each independently a hydrogen atom, alkyl group, cycloalkyl group, aryl group, alkoxy group, aryloxy group, alkoxycarbonyl group, alkylcarbonyloxy group, cycloalkylcarbonyloxy group, halogen atom, hydroxyl group Represents a nitro group, an alkylthio group or an arylthio group.
R _6c and R _7c each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group or an aryl group.
R _x and R _y each independently represents an alkyl group, a cycloalkyl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, an allyl group, or a vinyl group.

Any two or more of R _1c to R _5c , R _5c and R _6c , R _6c and R _7c , R _5c and R _x , and R _x and R _y may be bonded to form a ring structure. In addition, this ring structure may contain an oxygen atom, a sulfur atom, a ketone group, an ester bond, or an amide bond.
Examples of the ring structure include an aromatic or non-aromatic hydrocarbon ring, an aromatic or non-aromatic heterocycle, or a polycyclic fused ring formed by combining two or more of these rings. Examples of the ring structure include 3- to 10-membered rings, preferably 4- to 8-membered rings, more preferably 5- or 6-membered rings.
Examples of the group formed by combining any two or more of R _1c to R _5c , R _6c and R _7c , and R _x and R _y include a butylene group and a pentylene group.
The group formed by combining R _5c and R _6c and R _5c and R _x is preferably a single bond or an alkylene group, and examples of the alkylene group include a methylene group and an ethylene group. .

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

The alkyl group as R _1c to R _7c may be either linear or branched, for example, an alkyl group having 1 to 20 carbon atoms, preferably a linear or branched alkyl group having 1 to 12 carbon atoms ( Examples thereof include a methyl group, an ethyl group, a linear or branched propyl group, a linear or branched butyl group, and a linear or branched pentyl group. Examples of the cycloalkyl group include a cycloalkyl group having 3 to 10 carbon atoms. An alkyl group (for example, a cyclopentyl group, a cyclohexyl group) can be mentioned.

The aryl group as R _1c to R _5c preferably has 5 to 15 carbon atoms, and examples thereof include a phenyl group and a naphthyl group.

The alkoxy group as R _1c to R _{5c may} be linear, branched or cyclic, for example, an alkoxy group having 1 to 10 carbon atoms, preferably a linear or branched alkoxy group having 1 to 5 carbon atoms. (For example, methoxy group, ethoxy group, linear or branched propoxy group, linear or branched butoxy group, linear or branched pentoxy group), cyclic alkoxy group having 3 to 10 carbon atoms (for example, cyclopentyloxy group, cyclohexyloxy group) ).

Specific examples of the alkoxy group in the alkoxycarbonyl group as R _1c ~ R _5c are the same as specific examples of the alkoxy group as the R _1c ~ R _5c.

Specific examples of the alkyl group in the alkylcarbonyloxy group and alkylthio group as R _1c ~ R _5c are the same as specific examples of the alkyl group of the R _1c ~ R _5c.

Specific examples of the cycloalkyl group in the cycloalkyl carbonyl group as R _1c ~ R _5c are the same as specific examples of the cycloalkyl group of the R _1c ~ R _5c.

Specific examples of the aryl group in the aryloxy group and arylthio group as R _1c ~ R _5c are the same as specific examples of the aryl group of the R _1c ~ R _5c.
Preferably, any one of R _1c to R _5c is a linear or branched alkyl group, a cycloalkyl group, or a linear, branched or cyclic alkoxy group, and more preferably the sum of carbon numbers of R _1c to R _5c. Is 2-15. Thereby, solvent solubility improves more and generation | occurrence | production of a particle is suppressed at the time of a preservation | save.

The ring structure that any two or more of R _1c to R _5c may be bonded to each other is preferably a 5-membered or 6-membered ring, particularly preferably a 6-membered ring (for example, a phenyl ring). It is done.

The ring structure which may be formed by R _5c and R _6c are bonded to each other, bonded R _5c and R _6c are each other a single bond or an alkylene group (methylene group, ethylene group, etc.) by configuring the generally Examples thereof include a carbonyl carbon atom in formula (ZI-3) and a 4-membered or more ring formed with the carbon atom (particularly preferably a 5-6 membered ring).

The aryl group as R _6c and R _7c preferably has 5 to 15 carbon atoms, and examples thereof include a phenyl group and a naphthyl group.
As an aspect of R _6c and R _7c , it is preferable that both of them are alkyl groups. In particular, R _6c and R _7c are each preferably a linear or branched alkyl group having 1 to 4 carbon atoms, and particularly preferably both are methyl groups.

In addition, when R _6c and R _7c are combined to form a ring, the group formed by combining R _6c and R _7c is preferably an alkylene group having 2 to 10 carbon atoms, such as an ethylene group , Propylene group, butylene group, pentylene group, hexylene group and the like. The ring formed by combining R _6c and R _7c may have a hetero atom such as an oxygen atom in the ring.

_Examples of the alkyl group and cycloalkyl group as R _x and R _y include the same alkyl group and cycloalkyl group as in R _1c to R _7c .

_Examples of the 2-oxoalkyl group and 2-oxocycloalkyl group as R _x and R _y include groups having> C═O at the 2-position of the alkyl group and cycloalkyl group as R _1c to R _7c. .

Examples of the alkoxy group in the alkoxycarbonylalkyl group as R _x and R _y include the same alkoxy groups as in R _1c to R _5c , and examples of the alkyl group include an alkyl group having 1 to 12 carbon atoms. Preferably, a linear alkyl group having 1 to 5 carbon atoms (for example, a methyl group or an ethyl group) can be used.

The allyl group as R _x and R _y is not particularly limited, but is substituted with an unsubstituted allyl group or a monocyclic or polycyclic cycloalkyl group (preferably a cycloalkyl group having 3 to 10 carbon atoms). An allyl group is preferred.

The vinyl group as R _x and R _y is not particularly limited, but is substituted with an unsubstituted vinyl group or a monocyclic or polycyclic cycloalkyl group (preferably a cycloalkyl group having 3 to 10 carbon atoms). It is preferably a vinyl group.

The ring structure which may be formed by R _5c and R _x are bonded to each other, bonded R _5c and R _x each other a single bond or an alkylene group (methylene group, ethylene group, etc.) by configuring the generally Examples thereof include a 5-membered or more ring (particularly preferably a 5-membered ring) formed with a sulfur atom and a carbonyl carbon atom in the formula (ZI-3).

As the ring structure that R _x and R _y may be bonded to each other, divalent R _x and R _y (for example, a methylene group, an ethylene group, a propylene group, and the like) are represented by the general formula (ZI-3): A 5-membered or 6-membered ring formed with a sulfur atom, particularly preferably a 5-membered ring (that is, a tetrahydrothiophene ring).

R _x and R _y are preferably an alkyl group or cycloalkyl group having 4 or more carbon atoms, more preferably 6 or more, and still more preferably 8 or more alkyl groups or cycloalkyl groups.

R _1c to R _7c , R _x and R _y may further have a substituent. Examples of such a substituent include a halogen atom (for example, a fluorine atom), a hydroxyl group, a carboxyl group, a cyano group, a nitro group, Group, alkyl group, cycloalkyl group, aryl group, alkoxy group, aryloxy group, acyl group, arylcarbonyl group, alkoxyalkyl group, aryloxyalkyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkoxycarbonyloxy group, aryl An oxycarbonyloxy group etc. can be mentioned.

In the general formula (ZI-3), R _1c , R _2c , R _4c and R _5c each independently represent a hydrogen atom, and R _3c is a group other than a hydrogen atom, that is, an alkyl group, a cycloalkyl group, More preferably, it represents an aryl group, alkoxy group, aryloxy group, alkoxycarbonyl group, alkylcarbonyloxy group, cycloalkylcarbonyloxy group, halogen atom, hydroxyl group, nitro group, alkylthio group or arylthio group.

Examples of the cation of the compound represented by the general formula (ZI-2) or (ZI-3) in the present invention include the following specific examples.

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

In general formula (ZI-4),
R ₁₃ represents a hydrogen atom, a fluorine atom, a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, or a group having 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. These groups may have a substituent.
l represents an integer of 0-2.
r represents an integer of 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 group of R ₁₃ , R ₁₄ and R ₁₅ is linear or branched and preferably has 1 to 10 carbon atoms, and is preferably a methyl group, an ethyl group, n -Butyl group, t-butyl group and the like are preferable.

Examples of the cycloalkyl group represented by R ₁₃ , R ₁₄ and R ₁₅ include monocyclic or polycyclic cycloalkyl groups (preferably cycloalkyl groups having 3 to 20 carbon atoms), and in particular, cyclopropyl, cyclopentyl, cyclohexyl, Cycloheptyl and cyclooctyl are preferred.

The alkoxy group for R ₁₃ and R ₁₄ is linear or branched and preferably has 1 to 10 carbon atoms, and is preferably a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, or the like.

The alkoxycarbonyl group of R ₁₃ and R ₁₄ is linear or branched and preferably has 2 to 11 carbon atoms, and is preferably a methoxycarbonyl group, an ethoxycarbonyl group, an n-butoxycarbonyl group or the like.

Examples of the group having a cycloalkyl group of R ₁₃ and R ₁₄ include a monocyclic or polycyclic cycloalkyl group (preferably a cycloalkyl group having 3 to 20 carbon atoms), and examples thereof include a monocyclic or polycyclic cycloalkyl group. Examples thereof include a cycloalkyloxy group and an alkoxy group having a monocyclic or polycyclic cycloalkyl group. These groups may further have a substituent.

The monocyclic or polycyclic cycloalkyloxy group for R ₁₃ and R ₁₄ preferably has a total carbon number of 7 or more, more preferably a total carbon number of 7 or more and 15 or less, It is preferable to have a cycloalkyl group. Monocyclic cycloalkyloxy group having 7 or more carbon atoms in total is cyclopropyloxy group, cyclobutyloxy group, cyclopentyloxy group, cyclohexyloxy group, cycloheptyloxy group, cyclooctyloxy group, cyclododecanyloxy group, etc. Optionally substituted with an alkyl group, hydroxyl group, halogen atom (fluorine, chlorine, bromine, iodine), nitro group, cyano group, amide group, sulfonamido group, alkoxy group, alkoxycarbonyl group, acyl group, acetoxy A monocyclic cycloalkyloxy group having a substituent such as a group, an acyloxy group such as a butyryloxy group, or a carboxy group, and having a total carbon number of 7 or more in combination with any substituents on the cycloalkyl group To express.
Examples of the polycyclic cycloalkyloxy group having 7 or more total carbon atoms include a norbornyloxy group, a tricyclodecanyloxy group, a tetracyclodecanyloxy group, an adamantyloxy group, and the like.

The alkoxy group having a monocyclic or polycyclic cycloalkyl group of R ₁₃ and R ₁₄ preferably has a total carbon number of 7 or more, more preferably a total carbon number of 7 or more and 15 or less, An alkoxy group having a monocyclic cycloalkyl group is preferable. The alkoxy group having a total of 7 or more carbon atoms and having a monocyclic cycloalkyl group is methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptoxy, octyloxy, dodecyloxy, 2-ethylhexyloxy, isopropoxy, A monocyclic cycloalkyl group that may have the above-mentioned substituents is substituted on an alkoxy group such as sec-butoxy, t-butoxy, iso-amyloxy, etc., and the total carbon number including the substituents is 7 or more Represents things. Examples thereof include a cyclohexylmethoxy group, a cyclopentylethoxy group, a cyclohexylethoxy group, and the like, and a cyclohexylmethoxy group is preferable.

Examples of the alkoxy group having a polycyclic cycloalkyl group having a total carbon number of 7 or more include a norbornyl methoxy group, a norbornyl ethoxy group, a tricyclodecanyl methoxy group, a tricyclodecanyl ethoxy group, a tetracyclo group. A decanyl methoxy group, a tetracyclodecanyl ethoxy group, an adamantyl methoxy group, an adamantyl ethoxy group, etc. are mentioned, A norbornyl methoxy group, a norbornyl ethoxy group, etc. are preferable.

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 represented by R ₁₄ are linear, branched or cyclic, and preferably have 1 to 10 carbon atoms, such as methanesulfonyl group, ethanesulfonyl group, n-propanesulfonyl. Group, n-butanesulfonyl group, cyclopentanesulfonyl group, cyclohexanesulfonyl group and the like are preferable.

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 which two R ₁₅ may combine with 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 preferable Includes a 5-membered ring (that is, a tetrahydrothiophene ring), and may be condensed with an aryl group or a cycloalkyl group. The divalent 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, an alkoxy group. Examples thereof include a carbonyl group and an alkoxycarbonyloxy group. There may be a plurality of substituents for the ring structure, and they may be bonded to each other to form a ring (aromatic or non-aromatic hydrocarbon ring, aromatic or non-aromatic heterocyclic ring, or these A polycyclic fused ring formed by combining two or more rings may be formed.
R ₁₅ in the general formula (ZI-4) is preferably a methyl group, an ethyl group, a naphthyl group, a divalent group in which two R ₁₅ are bonded to each other to form a tetrahydrothiophene ring structure together with a sulfur atom.

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 of the compound represented by the general formula (ZI-4) in the present invention include the following.

Next, general formulas (ZII) and (ZIII) will be described.
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 of R ₂₀₄ to R ₂₀₇ is preferably a phenyl group or a naphthyl group, more preferably a phenyl group. The aryl group of R ₂₀₄ to R ₂₀₇ may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the skeleton of the aryl group having a heterocyclic structure include pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene.
The alkyl group and cycloalkyl group in R ₂₀₄ to R ₂₀₇ are preferably a linear or branched alkyl group having 1 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group), carbon Examples thereof include cycloalkyl groups having a number of 3 to 10 (cyclopentyl group, cyclohexyl group, norbornyl group).
The aryl group, alkyl group, and cycloalkyl group of R ₂₀₄ to R ₂₀₇ may have a substituent. Examples of the substituent that the aryl group, alkyl group, and cycloalkyl group represented by R ₂₀₄ to R ₂₀₇ may have include, for example, an alkyl group (for example, 1 to 15 carbon atoms) and a cycloalkyl group (for example, 3 to 15 carbon atoms). ), Aryl groups (for example, having 6 to 15 carbon atoms), alkoxy groups (for example, having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups, and the like.
Z ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of Z ^{− in} formula (ZI).

Examples of the acid generator further include compounds represented by general formulas (ZIV), (ZV), and (ZVI) described in paragraphs <0227> to <0228> of JP-A-2014-232310.

Among the acid generators, compounds represented by the general formulas (ZI) to (ZIII) are more preferable.
As the acid generator, compounds described in paragraph <0229> of JP-A-2014-232310 can also be suitably used.

Among acid generators, particularly preferable examples include, but are not limited to, acid generators described in paragraphs <0231> to <0240> of JP-A-2014-232310.

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.
An acid generator can be used individually by 1 type or in combination of 2 or more types.
The content of the compound that generates an acid upon irradiation with actinic rays or radiation (except when represented by the above general formula (ZI-3) or (ZI-4)) in the composition is actinic ray sensitive or Based on the total solid content of the radiation-sensitive resin composition, 0.1 to 30% by mass is preferable, more preferably 0.5 to 25% by mass, still more preferably 3 to 20% by mass, and particularly preferably 3 to 15%. % By mass.
When the acid generator is represented by the general formula (ZI-3) or (ZI-4), the content is preferably 5 to 35% by mass based on the total solid content of the composition. 6 to 30% by mass is more preferable, 6 to 30% by mass is further preferable, and 6 to 25% by mass is particularly preferable.

[3] Solvent (C)
The actinic ray-sensitive or radiation-sensitive resin composition used in the present invention may contain a solvent (C).
Examples of the solvent (C) include alkylene glycol monoalkyl ether carboxylates, alkylene glycol monoalkyl ethers, alkyl lactate esters, alkyl alkoxypropionates, cyclic lactones (preferably having 4 to 10 carbon atoms), and rings. Examples of the organic solvent include good monoketone compounds (preferably having 4 to 10 carbon atoms), alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate.
Specific examples of these solvents can include the solvents described in paragraphs <0441> to <0455> of US Patent Application Publication No. 2008/0187860.

In the present invention, a mixed solvent may be used as the solvent (C).
For example, 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, alkylene glycol monoalkyl ether acetate, alkyl alkoxypropionate, containing a ring Two or more kinds of mixed solvents selected from monoketone compounds, cyclic lactones, alkyl acetates and the like which may be used are preferable, and among these, propylene glycol monomethyl ether acetate (PGMEA, also known as 1-methoxy-2-acetoxypropane) (hereinafter, Solvent A), propylene glycol monomethyl ether (PGME), ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, propion car One or two solvents selected from sulfonate and butyl acetate (hereinafter also referred to as a solvent B) mixed solvent of is preferred.
The mixing ratio (solvent A / solvent B) (mass ratio) of the mixed solvent is from 1/99 to 99/1, preferably from 10/90 to 90/10, more preferably from 20/80 to 60/40.
The solvent (C) preferably contains propylene glycol monomethyl ether acetate (PGMEA), and is preferably a propylene glycol monomethyl ether acetate single solvent or a mixed solvent containing two or more kinds of propylene glycol monomethyl ether acetate.

[4] Hydrophobic resin (D)
The actinic ray-sensitive or radiation-sensitive resin composition used in the present invention is a hydrophobic resin (hereinafter referred to as “hydrophobic resin (D)” or simply “resin (D)”, particularly when applied to immersion exposure. May also be included). The hydrophobic resin (D) is preferably different from the resin (A). Moreover, it is preferable that hydrophobic resin (D) does not have an acid-decomposable group.
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. In addition, since uneven distribution of the hydrophobic resin (D) can be expected to suppress so-called outgassing, the hydrophobic resin (D) may be used when the pattern forming method of the present invention is performed by EUV exposure. preferable.
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.

When the hydrophobic resin (D) contains a fluorine atom and / or a silicon atom, the fluorine atom and / or silicon atom in the hydrophobic resin (D) may be contained in the main chain of the resin. , May be contained in the side chain.

When the hydrophobic resin (D) contains a fluorine atom, it is a resin having an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom, or an aryl group having a fluorine atom as a partial structure having a fluorine atom. Preferably there is.
The alkyl group having a fluorine atom (preferably having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms) is a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom. It may have a substituent other than.
The cycloalkyl group having a fluorine atom is a monocyclic or polycyclic cycloalkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and may further have a substituent other than a fluorine atom.
Examples of the aryl group having a fluorine atom include those in which at least one hydrogen atom of an aryl group such as a phenyl group or a naphthyl group is substituted with a fluorine atom, and may further have a substituent other than a fluorine atom. .

Preferred examples of the alkyl group having a fluorine atom, the cycloalkyl group having a fluorine atom, and the aryl group having a fluorine atom include groups represented by the following general formulas (F2) to (F4). The invention is not limited to this.

In general formulas (F2) to (F4),
R ₅₇ to R ₆₈ each independently represents a hydrogen atom, a fluorine atom or an alkyl group (straight or branched). Provided that at least one of R ₅₇ to R _61, at least one of R ₆₂ to R ₆₄ , and at least one of R ₆₅ to R ₆₈ are each independently a fluorine atom or at least one hydrogen atom substituted with a fluorine atom. Represents an alkyl group (preferably having 1 to 4 carbon atoms).
R ₅₇ to R ₆₁ and R ₆₅ to R ₆₇ are preferably all fluorine atoms. R ₆₂ , R ₆₃ and R ₆₈ are preferably an alkyl group (preferably having 1 to 4 carbon atoms) in which at least one hydrogen atom is substituted with a fluorine atom, and preferably a perfluoroalkyl group having 1 to 4 carbon atoms. Further preferred. R ₆₂ and R ₆₃ may be connected to each other to form a ring.

Specific examples of the group represented by the general formula (F2) include a p-fluorophenyl group, a pentafluorophenyl group, and a 3,5-di (trifluoromethyl) phenyl group.
Specific examples of the group represented by the general formula (F3) include trifluoromethyl group, pentafluoropropyl group, pentafluoroethyl group, heptafluorobutyl group, hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2 -Methyl) isopropyl group, nonafluorobutyl group, octafluoroisobutyl group, nonafluorohexyl group, nonafluoro-t-butyl group, perfluoroisopentyl group, perfluorooctyl group, perfluoro (trimethyl) hexyl group, 2,2 , 3,3-tetrafluorocyclobutyl group, perfluorocyclohexyl group and the like. Hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro (2-methyl) isopropyl group, octafluoroisobutyl group, nonafluoro-t-butyl group and perfluoroisopentyl group are preferable, and hexafluoroisopropyl group and heptafluoroisopropyl group are preferable. Further preferred.
Specific examples of the group represented by the general formula (F4) include, for example, —C (CF ₃ ) ₂ OH, —C (C ₂ F ₅ ) ₂ OH, —C (CF ₃ ) (CH ₃ ) OH, —CH (CF ₃ ) OH and the like can be mentioned, and —C (CF ₃ ) ₂ OH is preferable.

The partial structure containing a fluorine atom may be directly bonded to the main chain, and further from the group consisting of an alkylene group, a phenylene group, an ether bond, a thioether bond, a carbonyl group, an ester bond, an amide bond, a urethane bond and a ureylene bond. You may couple | bond with a principal chain through the group selected or the group which combined these 2 or more types.

Hereinafter, as specific examples of the repeating unit having a fluorine atom, paragraphs <0274> to <0276> of JP 2012-073402 (corresponding to paragraph <0398> of the specification of US Patent Application Publication No. 2012/077122) <0399>) can be referred to, the contents of which are incorporated herein.

The hydrophobic resin (D) may contain a silicon atom. As a partial structure having a silicon atom, described in paragraphs <0277> to <0281> of JP 2012-073402 (corresponding to paragraphs <0400> to <0405> of US Patent Application Publication No. 2012/077122) The contents of which are incorporated herein by reference.

Further, as described above, the hydrophobic resin (D) also preferably includes a “CH ₃ partial structure” in the side chain portion.
Here, the hydrophobic resin (D) CH ₃ partial structure contained in the side chain moiety in (hereinafter, simply referred to as "side chain CH ₃ partial structure") The, CH ₃ parts ethyl, and propyl groups have Includes structure.
On the other hand, a methyl group directly bonded to the main chain of the hydrophobic resin (D) (for example, an α-methyl group of a repeating unit having a methacrylic acid structure) is caused by the influence of the main chain on the surface of the hydrophobic resin (D). Since the contribution to uneven distribution is small, it is not included in the “CH ₃ partial structure”.

More specifically, the hydrophobic resin (D) is a repeating unit derived from a monomer having a polymerizable moiety having a carbon-carbon double bond, such as a repeating unit represented by the following general formula (M). In the case where R ₁₁ to R ₁₄ are CH ₃ “as is”, the CH ₃ is not included in the “CH ₃ partial structure” of the side chain moiety.
On the other hand, when CH ₃ exists from the CC main chain through some atom, it corresponds to “CH ₃ partial structure”. For example, when R ₁₁ is an ethyl group (CH ₂ CH ₃ ), it has “one” CH ₃ partial structure.

In the general formula (M),
R ₁₁ to R ₁₄ each independently represents a side chain portion.
Examples of the side chain R ₁₁ to R ₁₄ include a hydrogen atom and a monovalent organic group.
Examples of monovalent organic groups for R ₁₁ to R ₁₄ include alkyl groups, cycloalkyl groups, aryl groups, alkyloxycarbonyl groups, cycloalkyloxycarbonyl groups, aryloxycarbonyl groups, alkylaminocarbonyl groups, cycloalkylaminocarbonyls. Group, an arylaminocarbonyl group, and the like, and these groups may further have a substituent.

The hydrophobic resin (D) is preferably a resin having a repeating unit having a CH ₃ partial structure in the side chain portion, and as such a repeating unit, a repeating unit represented by the following general formula (II), and It is more preferable to have at least one repeating unit (x) among repeating units represented by the following general formula (III).

Hereinafter, the repeating unit represented by the general formula (II) will be described in detail.

In the general formula (II), X _b1 represents a hydrogen atom, an alkyl group, a cyano group or a halogen atom, R ₂ has one or more CH ₃ partial structure represents a stable organic radical to acid. Here, the organic group stable to an acid is more specifically an organic group that does not have the “group that decomposes by the action of an acid to generate a polar group” described in the resin (A). Is preferred.

The alkyl group for X _b1 preferably has 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, and a trifluoromethyl group, and a methyl group is preferable.
X _b1 is preferably a hydrogen atom or a methyl group.

Examples of R ₂ include an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an aryl group, and an aralkyl group having one or more CH ₃ partial structures. The above cycloalkyl group, alkenyl group, cycloalkenyl group, aryl group and aralkyl group may further have an alkyl group as a substituent.
R ₂ is preferably an alkyl group or an alkyl-substituted cycloalkyl group having one or more CH ₃ partial structures.
The acid-stable organic group having one or more CH ₃ partial structures as R ₂ preferably has 2 or more and 10 or less CH ₃ partial structures, and more preferably 2 or more and 8 or less.

The alkyl group having one or more CH ₃ partial structures in R ₂ is preferably a branched alkyl group having 3 to 20 carbon atoms.

The cycloalkyl group having one or more CH ₃ partial structures in R ₂ may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The number of carbon atoms is preferably 6-30, and particularly preferably 7-25.
The alkenyl group having one or more CH ₃ partial structures in R ₂ is preferably a linear or branched alkenyl group having 1 to 20 carbon atoms, more preferably a branched alkenyl group.
The aryl group having one or more CH ₃ partial structures in R ₂ is preferably an aryl group having 6 to 20 carbon atoms, and examples thereof include a phenyl group and a naphthyl group. is there.
The aralkyl group having one or more CH ₃ partial structures in R ₂ is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.

Preferred specific examples of the repeating unit represented by the general formula (II) are listed below. The present invention is not limited to this.

The repeating unit represented by the general formula (II) is preferably an acid-stable (non-acid-decomposable) repeating unit, and specifically, a group that decomposes by the action of an acid to generate a polar group. It is preferable that it is a repeating unit which does not have.

Hereinafter, the repeating unit represented by the general formula (III) will be described in detail.

In the general formula (III), X _b2 represents a hydrogen atom, an alkyl group, a cyano group, or a halogen atom, R ₃ represents an acid-stable organic group having one or more CH ₃ partial structures, n represents an integer of 1 to 5.

The alkyl group for X _b2 preferably has 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, and a trifluoromethyl group, and a hydrogen atom is preferable.
X _b2 is preferably a hydrogen atom.

Since R ₃ is an organic group that is stable against an acid, more specifically, it is an organic group that does not have the “group that decomposes by the action of an acid to generate a polar group” described in the resin (A). Preferably there is.

R ₃ includes an alkyl group having one or more CH ₃ partial structures.
The acid-stable organic group having one or more CH ₃ partial structures as R ₃ preferably has 1 or more and 10 or less CH ₃ partial structures, more preferably 1 or more and 8 or less, More preferably, it is 1 or more and 4 or less.

The alkyl group having one or more CH ₃ partial structures in R ₃ is preferably a branched alkyl group having 3 to 20 carbon atoms.

N represents an integer of 1 to 5, more preferably an integer of 1 to 3, and still more preferably 1 or 2.

Preferred specific examples of the repeating unit represented by the general formula (III) are given below. The present invention is not limited to this.

The repeating unit represented by the general formula (III) is preferably an acid-stable (non-acid-decomposable) repeating unit, and specifically, a group that decomposes by the action of an acid to generate a polar group. It is preferable that it is a repeating unit which does not have.

In the case where the hydrophobic resin (D) contains a CH ₃ partial structure in the side chain portion, and particularly when it does not have a fluorine atom and a silicon atom, the repeating unit represented by the general formula (II), and The content of at least one repeating unit (x) among the repeating units represented by the general formula (III) is preferably 90 mol% or more based on all repeating units of the hydrophobic resin (D). More preferably, it is 95 mol% or more. The content is usually 100 mol% or less with respect to all repeating units of the hydrophobic resin (D).

The hydrophobic resin (D) comprises at least one repeating unit (x) among the repeating unit represented by the general formula (II) and the repeating unit represented by the general formula (III). ), The surface free energy of the hydrophobic resin (D) increases. As a result, the hydrophobic resin (D) is less likely to be unevenly distributed on the surface of the resist film, and the static / dynamic contact angle of the resist film with respect to water can be reliably improved and the immersion liquid followability can be improved. it can.

In addition, the hydrophobic resin (D) includes (i) a fluorine atom and / or a silicon atom, and (ii) a case where a side chain portion includes a CH ₃ partial structure. And may have at least one group selected from the group (x) to (z) described in paragraphs <0283> to <0290>.
(X) an acid group,
(Y) a group having a lactone structure, an acid anhydride group, or an acid imide group,
(Z) a group decomposable by the action of an acid

The hydrophobic resin (D) may further have a repeating unit represented by the general formula (III) described in paragraphs <0292> to <0294> of JP-A-2014-232310.
The hydrophobic resin (D) preferably further has a repeating unit represented by the general formula (CII-AB) described in paragraphs <0296> to <0299> of JP-A-2014-232310. .

When the hydrophobic resin (D) has a fluorine atom, the fluorine atom content is preferably 5 to 80% by mass with respect to the weight average molecular weight of the hydrophobic resin (D), and is 10 to 80% by mass. More preferably. Further, the repeating unit containing a fluorine atom is preferably 10 to 100 mol%, more preferably 30 to 100 mol% in all repeating units contained in the hydrophobic resin (D).
When the hydrophobic resin (D) has a silicon atom, the content of the silicon atom is preferably 2 to 50% by mass with respect to the weight average molecular weight of the hydrophobic resin (D), and is 2 to 30% by mass. More preferably. Further, the repeating unit containing a silicon atom is preferably 10 to 100 mol%, more preferably 20 to 100 mol% in all repeating units contained in the hydrophobic resin (D).

On the other hand, particularly when the hydrophobic resin (D) contains a CH ₃ partial structure in the side chain portion, it is also preferable that the resin (D) contains substantially no fluorine atom or silicon atom. The content of the repeating unit having a fluorine atom or a silicon atom is preferably 5 mol% or less, more preferably 3 mol% or less, based on all repeating units in the hydrophobic resin (D). It is preferably 1 mol% or less, ideally 0 mol%, that is, it does not contain a fluorine atom and a silicon atom. Moreover, it is preferable that hydrophobic resin (D) is substantially comprised only by the repeating unit comprised only by the atom chosen from a carbon atom, an oxygen atom, a hydrogen atom, a nitrogen atom, and a sulfur atom. More specifically, the repeating unit composed only of atoms selected from a carbon atom, an oxygen atom, a hydrogen atom, a nitrogen atom and a sulfur atom is 95 mol% or more in all the repeating units of the hydrophobic resin (D). It is preferably 97 mol% or more, more preferably 99 mol% or more, and ideally 100 mol%.

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.
In addition, 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, preferably 0.05 to 8% by mass with respect to the total solid content in the actinic ray-sensitive or radiation-sensitive resin composition. % Is more preferable, and 0.1 to 7% by mass is even more preferable.

The hydrophobic resin (D), like the resin (A), naturally has few impurities such as metals, and the residual monomer and oligomer components are 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.
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.

Specific examples of the hydrophobic resin (D) include resins described in paragraphs <0306> to <0315> of JP 2014-232310.

[5] Basic compound The actinic ray-sensitive or radiation-sensitive resin composition used in the present invention may contain a basic compound in order to reduce a change in performance over time from exposure to heating. Usable basic compounds are not particularly limited, and for example, compounds classified into the following (1) to (5) can be used.

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

In general formulas (A) and (E),
R ²⁰⁰ , R ²⁰¹ and R 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). 6-20), wherein R ²⁰¹ and R ²⁰² may combine with each other to form a ring.
R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different and each represents an alkyl group having 1 to 20 carbon atoms.

Regarding the alkyl group, the alkyl group having a substituent is preferably an aminoalkyl group having 1 to 20 carbon atoms, a hydroxyalkyl group having 1 to 20 carbon atoms, or a cyanoalkyl group having 1 to 20 carbon atoms.
The alkyl groups in the general formulas (A) and (E) are more preferably unsubstituted.
Preferable compound (N) includes guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, piperidine, and more preferable compound (N) includes imidazole structure, diazabicyclo structure, onium hydroxy group. Compound (N) having an alkyl group structure, an onium carboxylate structure, a trialkylamine structure, an aniline structure or a pyridine structure, an alkylamine derivative having a hydroxyl group and / or an ether bond, an aniline derivative having a hydroxyl group and / or an ether bond, etc. Specific examples thereof include the compounds described in paragraph <0321> of JP 2014-232310.

Preferred examples of the basic compound (N) 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. Examples of these compounds include compounds (C1-1) to (C3-3) exemplified in paragraph <0066> of US Patent Application Publication No. 2007 / 02245539A1.

The following compounds are also preferable as the basic compound (N).

As the basic compound (N), in addition to the above-mentioned compounds, paragraphs <0180> to <0225> of JP2011-22560A, paragraphs [0218] to <0219> of JP2012-137735A, The compounds described in paragraphs <0416> to <0438> of WO 2011/158687 can also be used. The basic compound (N) may be a basic compound or an ammonium salt compound whose basicity is lowered by irradiation with actinic rays or radiation.
These basic compounds (N) may be used alone or in combination of two or more.

The actinic ray-sensitive or radiation-sensitive resin composition may or may not contain the basic compound (N). The amount is usually 0.001 to 10% by mass, preferably 0.01 to 5% by mass, based on the solid content of the radiation-sensitive resin composition.
The use ratio of the acid generator and the basic compound (N) in the composition is preferably acid generator / basic compound (molar ratio) = 2.5 to 300. That is, the molar ratio is preferably 2.5 or more from the viewpoint of sensitivity and resolution, and is preferably 300 or less from the viewpoint of suppressing resolution from being reduced due to the thickening of the resist pattern over time until post-exposure heat treatment. The acid generator / basic compound (N) (molar ratio) is more preferably from 5.0 to 200, still more preferably from 7.0 to 150.

(2) Basic compound or ammonium salt compound (E) whose basicity is reduced by irradiation with actinic rays or radiation
The actinic ray-sensitive or radiation-sensitive resin composition may contain a basic compound or an ammonium salt compound (hereinafter also referred to as “compound (E)”) whose basicity is lowered by irradiation with actinic rays or radiation. preferable.
The compound (E) is preferably a compound (E-1) having a basic functional group or an ammonium group and a group capable of generating an acidic functional group upon irradiation with actinic rays or radiation. That is, the compound (E) is a basic compound having a basic functional group and a group capable of generating an acidic functional group upon irradiation with active 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.
The compound of the following general formula (PA-I), (PA-II) or (PA) is produced as a compound with reduced basicity, which is generated by the decomposition of compound (E) or (E-1) by irradiation with actinic rays or radiation. And compounds represented by -III). In particular, from the viewpoint of achieving excellent effects on LWR, uniformity of local pattern dimensions, and DOF at a high level, in particular, a compound represented by the general formula (PA-II) or (PA-III) is used. preferable.
First, the compound represented by formula (PA-I) will be described.
QA _1- (X) _n -BR (PA-I)
In the general formula (PA-I),
A ₁ represents a single bond or a divalent linking group.
Q represents —SO ₃ H or —CO ₂ H. Q corresponds to an acidic functional group generated by irradiation with actinic rays or radiation.
X represents —SO ₂ — or —CO—.
n represents 0 or 1.
B represents a single bond, an oxygen atom or —N (Rx) —.
Rx represents a hydrogen atom or a monovalent organic group.
R represents a monovalent organic group having a basic functional group or a monovalent organic group having an ammonium group.
Next, the compound represented by formula (PA-II) will be described.
Q ₁ -X ₁ -NH-X ₂ -Q ₂ (PA-II)
In general formula (PA-II),
Q ₁ and Q ₂ each independently represents a monovalent organic group. However, either Q ₁ or Q ₂ has a basic functional group. Q ₁ and Q ₂ may combine to form a ring, and the formed ring may have a basic functional group.
X ₁ and X ₂ each independently represents —CO— or —SO ₂ —.
Note that —NH— corresponds to an acidic functional group generated by irradiation with actinic rays or radiation.
Next, the compound represented by formula (PA-III) will be described.
Q ₁ -X ₁ -NH-X ₂ -A _2- (X ₃ ) _m -BQ ₃ (PA-III)
In the general formula (PA-III),
Q ₁ and Q ₃ each independently represents a monovalent organic group. However, either Q ₁ or Q ₃ has a basic functional group. Q ₁ and Q ₃ may combine to form a ring, and the formed ring may have a basic functional group.
X ₁ , X ₂ and X ₃ each independently represents —CO— or —SO ₂ —.
A ₂ represents a divalent linking group.
B represents a single bond, an oxygen atom or —N (Qx) —.
Qx represents a hydrogen atom or a monovalent organic group.
When B is —N (Qx) —, Q ₃ and Qx may combine to form a ring.
m represents 0 or 1.
Note that —NH— corresponds to an acidic functional group generated by irradiation with actinic rays or radiation.

Hereinafter, specific examples of the compound (E) will be given, but the present invention is not limited thereto. In addition to the exemplified compounds, preferred specific examples of the compound (E) include compounds (A-1) to (A-44) of US Patent Application Publication No. 2010/0233629, and US Patent Application Publication No. 2012. No. 0156617 (A-1) to (A-23) and the like.

The molecular weight of the compound (E) is preferably 500 to 1,000.
The actinic ray-sensitive or radiation-sensitive resin composition may or may not contain the compound (E), but when it is contained, the content of the compound (E) is the actinic ray-sensitive or radiation-sensitive resin. The content is preferably 0.1 to 20% by mass, more preferably 0.1 to 10% by mass, based on the solid content of the composition.
Further, as one embodiment of the compound (E), a compound (E-2) that generates an acid (weak acid) having a strength that does not decompose the acid-decomposable group of the resin (A) by acid irradiation or radiation irradiation. Can also be mentioned.
Examples of the compound include an onium salt of a carboxylic acid having no fluorine atom (preferably a sulfonium salt) and an onium salt of a sulfonic acid having no fluorine atom (preferably a sulfonium salt). More specifically, for example, among onium salts represented by the following general formula (6A), those in which the carboxylic acid anion does not have a fluorine atom, among onium salts represented by the following general formula (6B) Examples include those in which the sulfonate anion does not have a fluorine atom. As a cation structure of a sulfonium salt, the sulfonium cation structure mentioned by the acid generator (B) can be mentioned preferably.
More specifically, examples of the compound (E-2) include compounds listed in paragraph <0170> of WO 2012/053527, and paragraphs <0268> to <0269> of JP2012-173419A. Compound etc. are mentioned.
A compound (E) may be used individually by 1 type, and may be used in combination of 2 or more type.

(3) Low molecular weight compound (F) having a nitrogen atom and a group capable of leaving by the action of an acid
The actinic ray-sensitive or radiation-sensitive resin composition may contain a compound having a nitrogen atom and a group capable of leaving by the action of an acid (hereinafter also referred to as “compound (F)”).
The group capable of leaving by the action of an acid is not particularly limited, but is preferably an acetal group, a carbonate group, a carbamate group, a tertiary ester group, a tertiary hydroxyl group, or a hemiaminal ether group, and a carbamate group or a hemiaminal ether group. It is particularly preferred.
The molecular weight of the compound (N ″) having a group capable of leaving by the action of an acid is preferably 100 to 1000, more preferably 100 to 700, and particularly preferably 100 to 500.
As the compound (F), an amine derivative having a group capable of leaving by the action of an acid on the nitrogen atom is preferable.

Compound (F) may have a carbamate group having a protecting group on the nitrogen atom. The protecting group constituting the carbamate group can be represented by the following general formula (d-1).

In general formula (d-1),
R _b is independently a hydrogen atom, an alkyl group (preferably having 1 to 10 carbon atoms), a cycloalkyl group (preferably having 3 to 30 carbon atoms), an aryl group (preferably having 3 to 30 carbon atoms), an aralkyl group. (Preferably having 1 to 10 carbon atoms) or an alkoxyalkyl group (preferably having 1 to 10 carbon atoms). R _b may be connected to each other to form a ring.

The alkyl group, cycloalkyl group, aryl group, and aralkyl group represented by R _b are substituted with a functional group such as a hydroxyl group, a cyano group, an amino group, a pyrrolidino group, a piperidino group, a morpholino group, and an oxo group, an alkoxy group, and a halogen atom. May be. The same applies to the alkoxyalkyl group represented by R _b .
R _b is preferably a linear or branched alkyl group, cycloalkyl group, or aryl group. More preferably, it is a linear or branched alkyl group or cycloalkyl group.

Examples of the ring formed by connecting two R _b to each other include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a heterocyclic hydrocarbon group, or a derivative thereof.
Examples of the specific structure of the group represented by the general formula (d-1) include the structure disclosed in paragraph <0466> of US Patent Application Publication No. 2012/0135348. It is not limited.

The compound (F) particularly preferably has a structure represented by the following general formula (6).

In the general formula (6), R _a represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. When l is 2, two R _a may be the same or different, and two R _a may be connected to each other to form a heterocyclic ring together with the nitrogen atom in the formula. The heterocycle may contain a heteroatom other than the nitrogen atom in the formula.
R _b has the same meaning as R _b in formula (d-1), and preferred examples are also the same.
l represents an integer of 0 to 2, m represents an integer of 1 to 3, and satisfies l + m = 3.

In the general formula (6), an alkyl group, a cycloalkyl group, an aryl group, and an aralkyl group as R _a are groups in which the alkyl group, cycloalkyl group, aryl group, and aralkyl group as R _b may be substituted. It may be substituted with a group similar to the group described above.
Preferred examples of the alkyl group, cycloalkyl group, aryl group, and aralkyl group represented by R _a (these alkyl group, cycloalkyl group, aryl group, and aralkyl group may be substituted with the above groups) The same group as the preferable example mentioned above about _Rb is mentioned.
The heterocyclic ring formed by connecting R _a to each other preferably has 20 or less carbon atoms. For example, pyrrolidine, piperidine, morpholine, 1,4,5,6-tetrahydropyrimidine, 1,2,3 , 4-tetrahydroquinoline, 1,2,3,6-tetrahydropyridine, homopiperazine, 4-azabenzimidazole, benzotriazole, 5-azabenzotriazole, 1H-1,2,3-triazole, 1,4,7 Triazacyclononane, tetrazole, 7-azaindole, indazole, benzimidazole, imidazo [1,2-a] pyridine, (1S, 4S)-(+)-2,5-diazabicyclo [2.2.1] Heptane, 1,5,7-triazabicyclo [4.4.0] dec-5-ene, indole, indoline, 1,2,3 -Groups derived from heterocyclic compounds such as tetrahydroquinoxaline, perhydroquinoline, 1,5,9-triazacyclododecane, and groups derived from these heterocyclic compounds derived from linear and branched alkanes Groups derived from cycloalkanes, groups derived from aromatic compounds, groups derived from heterocyclic compounds, hydroxyl groups, cyano groups, amino groups, pyrrolidino groups, piperidino groups, morpholino groups, oxo groups, etc. Or a group substituted with one or more of the above.

Specific examples of the preferred compound (F) include, but are not limited to, compounds disclosed in paragraph <0475> of US Patent Application Publication No. 2012/0135348.

The compound represented by the general formula (6) can be synthesized based on JP2007-298869A, JP2009-199021A, and the like.
In the present invention, the low molecular compound (F) can be used singly or in combination of two or more.
The content of the compound (F) in the actinic ray-sensitive or radiation-sensitive resin composition is preferably 0.001 to 20% by mass, more preferably 0.001 based on the total solid content of the composition. To 10% by mass, more preferably 0.01 to 5% by mass.

(4) Onium salt Moreover, as a basic compound, you may include the onium salt represented by the following general formula (6A) or (6B). 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 acid 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 acid generator described above, the fluorine atom is not substituted 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. Of 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.
Preferred examples of the sulfonium cation and the iodonium cation include the aforementioned sulfonium cation structure of the general formula (ZI) and the iodonium structure of the general formula (ZII) in the compound (B).

A specific structure of the onium salt represented by the general formula (6A) or (6B) is shown below.
In addition, onium salt may be used individually by 1 type, and may be used in combination of 2 or more types.

(5) Betaine compound Further, the composition includes a compound contained in the formula (I) of JP 2012-189977 A, a compound represented by the formula (I) of JP 2013-6827 A, Both an onium salt structure and an acid anion structure in one molecule, such as a compound represented by the formula (I) of No. 8020 and a compound represented by the formula (I) of JP 2012-252124 A A compound having the same (hereinafter also referred to as betaine compound) can be preferably used. Examples of the onium salt structure include a sulfonium, iodonium, and ammonium structure, and a sulfonium or iodonium salt structure is preferable. Moreover, as an acid anion structure, a sulfonate anion or a carboxylate anion is preferable. Examples of this compound include the following.
In addition, a betaine compound may be used individually by 1 type, and may be used in combination of 2 or more type.

The actinic ray-sensitive or radiation-sensitive resin composition used in the present invention is composed of (1) a basic compound (N), (2) a basic compound or ammonium whose basicity is reduced by irradiation with an actinic ray or radiation. Selected from the group consisting of a salt compound (E), (3) a low molecular compound (F) having a nitrogen atom and a group capable of leaving by the action of an acid, (4) an onium salt, and (5) a betaine compound. Two or more compounds may be contained.

[6] Surfactant (F)
The actinic ray-sensitive or radiation-sensitive resin composition used in the present invention may further contain a surfactant. In the case of containing a surfactant, either fluorine and / or silicon surfactant (fluorine surfactant, silicon surfactant, surfactant having both fluorine atom and silicon atom), or two kinds It is more preferable to contain the above.

When the actinic ray-sensitive or radiation-sensitive resin composition contains a surfactant, a resist pattern with good sensitivity and resolution and less adhesion and development defects when using an exposure light source of 250 nm or less, particularly 220 nm or less. Can be given.
As surfactants such as fluorine-based and / or silicon-based surfactants, for example, surfactants described in paragraphs <0353> to <0355> of JP-A-2014-232310 can be used.

These surfactants may be used alone or in some combination.

When the actinic ray-sensitive or radiation-sensitive resin composition contains a surfactant, the amount of the surfactant used is based on the total amount of the actinic ray-sensitive or radiation-sensitive resin composition (excluding the solvent). The content is preferably 0.0001 to 2% by mass, more preferably 0.0005 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 actinic ray-sensitive or radiation-sensitive resin composition includes an acid proliferator, 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 phenol compound having a molecular weight of 1000 or less, an alicyclic compound having a carboxyl group, or an aliphatic compound) may be contained.

Such phenol compounds having a molecular weight of 1000 or less are described in, for example, JP-A-4-122938, JP-A-2-28531, US Pat. No. 4,916,210, European Patent 219294, and the like. It can be easily synthesized by those skilled in the art with reference to the method described.
Specific examples of alicyclic or aliphatic compounds having a carboxyl group include carboxylic acid derivatives having a steroid structure such as cholic acid, deoxycholic acid, lithocholic acid, adamantane carboxylic acid derivatives, adamantane dicarboxylic acid, cyclohexane carboxylic acid, cyclohexane Examples include, but are not limited to, dicarboxylic acids.

The actinic ray-sensitive or radiation-sensitive resin composition 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. Such a film thickness can be obtained by setting the solid content concentration in the composition to an appropriate range to give an appropriate viscosity and improving the coating property and film forming property.
The solid content concentration of the actinic ray-sensitive or radiation-sensitive resin composition is usually 1.0 to 10% by mass, preferably 2.0 to 5.7% by mass, 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, and further, a resist pattern having excellent line width roughness can be formed. The reason for this is not clear, but perhaps the solid content concentration is 10% by mass or less, preferably 5.7% by mass or less, whereby aggregation of the material in the resist solution, particularly the acid generator, is suppressed, As a result, it is considered that a uniform resist film was formed.
The solid content concentration is a weight percentage of the weight of other resist components excluding the solvent with respect to the total weight of the actinic ray-sensitive or radiation-sensitive resin composition.

The actinic ray-sensitive or radiation-sensitive resin composition is preferably prepared by dissolving the above components in a predetermined organic solvent, preferably the above mixed solvent.
During the preparation, a process of reducing metal impurities in the composition to the ppb level using an ion exchange membrane, a process of filtering impurities such as various particles using an appropriate filter, a deaeration process, etc. Good. Specifics of these steps are described in JP 2012-88574 A, JP 2010-189563 A, JP 2001-12529 A, JP 2001-350266 A, and JP 2002-99076 A. JP-A-5-307263, JP-A-2010-164980, International Publication No. 2006/121162, JP-A-2010-243866, JP-A-2010-020297, and the like.
In particular, with respect to a suitable filter used in the filtering step, a pore size of 0.1 μm or less, more preferably 0.05 μm or less, and further preferably 0.03 μm or less made of polytetrafluoroethylene, polyethylene, or nylon is used. preferable.
The actinic ray-sensitive or radiation-sensitive resin composition preferably has a low water content. Specifically, the water content is preferably 2.5% by mass or less, more preferably 1.0% by mass or less, and still more preferably 0.3% by mass or less in the total weight of the composition.

(Procedure of step (1))
The method for forming a film on the substrate using the actinic ray-sensitive or radiation-sensitive resin composition is not particularly limited, and a known method can be adopted. Especially, the method of apply | coating the said actinic-light sensitive or radiation sensitive resin composition on a board | substrate from the point which adjustment of the thickness of a film | membrane is easier is mentioned.
The application method is not particularly limited, and a known method can be adopted. Among these, spin coating is preferably used in the semiconductor manufacturing field.
Moreover, you may implement the drying process for removing a solvent as needed after apply | coating actinic-ray-sensitive or radiation-sensitive resin composition. The method for the drying treatment is not particularly limited, and examples thereof include heat treatment and air drying treatment.

In the present invention, the substrate on which the resist film is formed is not particularly limited, and is generally used in a semiconductor manufacturing process such as an IC, a manufacturing process of a circuit board such as a liquid crystal or a thermal head, and other photofabrication lithography processes. A substrate can be used, and examples thereof include inorganic substrates such as silicon (silicon wafer), SiO ₂ and SiN.
A conventionally known lower layer film (inorganic film or organic film) may be formed between the substrate and the resist film (lower layer of the resist film) as necessary. Examples of the lower layer film include an SOC (Spin On Carbon) film, an SOG (Spin On Glass) film, an SiON film (silicon nitride oxide film), an organic antireflection film (BARC), and the like.

The receding contact angle of a film (resist film) formed using the actinic ray-sensitive or radiation-sensitive resin composition in the present invention is preferably 70 ° or more at a temperature of 23 ± 3 ° C. and a humidity of 45 ± 5%. 75 ° or more, more preferably 75 to 85 °. When the receding contact angle of the resist film is in the above range, it is suitable for exposure through an immersion medium.
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 in the actinic ray-sensitive or radiation-sensitive composition. In order to improve the receding contact angle, an upper layer film (so-called “top coat”) may be formed on the resist film, as will be described later.

The thickness of the resist film is not particularly limited, but is preferably 1 to 500 nm and more preferably 1 to 100 nm because a fine pattern with higher accuracy can be formed.

An upper layer film (top coat) may be formed on the resist film using a composition containing a hydrophobic resin (upper layer film forming composition).
Examples of the hydrophobic resin contained in the composition for forming an upper layer film include, but are not limited to, resins described as hydrophobic resins that may be contained in the composition for forming a resist film.
In addition, in the composition for forming an upper layer film, conventionally known additives and solvents can be appropriately used.
In addition, when peeling an upper layer film (topcoat), as an upper layer film peeling solvent, the organic type developing solution mentioned later may be used and a peeling agent may be used separately.

[Step (2): Exposure step]
Step (2) is a step of exposing the film formed in step (1). More specifically, it is a step of selectively exposing the film so that a desired pattern is formed. As a result, the film is exposed in a pattern, and the solubility of the resist film changes only in the exposed part.
Note that “exposing” means irradiating with actinic rays or radiation.

The light used for the exposure is not particularly limited, and examples thereof include infrared light, visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light, X-rays, and electron beams. Preferably, it is far ultraviolet light having a wavelength of 250 nm or less, more preferably 220 nm or less, and still more preferably 1 to 200 nm.
More specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), F ₂ excimer laser (157 nm), X-ray, EUV (13 nm), electron beam, and the like can be mentioned. ArF excimer laser, EUV or electron beam is preferable, and ArF excimer laser is more preferable.

The method for selectively exposing the film is not particularly limited, and a known method can be used. For example, a binary mask (Binary-Mask) in which the transmittance of the light shielding portion is 0%, a halftone phase shift mask (HT-Mask) in which the transmittance of the light shielding portion is 6%, or the like can be used.
In general, a binary mask is used in which a chromium film, a chromium oxide film, or the like is formed on a quartz glass substrate as a light shielding portion.
A halftone phase shift mask is generally used in which a MoSi (molybdenum silicide) film, a chromium film, a chromium oxide film, a silicon oxynitride film or the like is formed on a quartz glass substrate as a light shielding portion.
In the present invention, the exposure is not limited to exposure through a photomask, and selective exposure (pattern exposure) may be performed by exposure without using a photomask, for example, drawing with an electron beam or the like.
This step may include multiple exposures.

(Heat treatment)
Prior to this step, heat treatment (PB: Prebake) may be performed on the film. Heat treatment (PB) may be performed a plurality of times.
Moreover, you may perform a heat processing (PEB: Post Exposure Bake) with respect to a resist film after this process. The heat treatment (PEB) may be performed a plurality of times.
The heat treatment promotes the reaction of the exposed area, further improving the sensitivity and pattern profile.
For both PB and PEB, the temperature of the heat treatment is preferably 70 to 130 ° C., more preferably 80 to 120 ° C.
For both PB and PEB, the heat treatment time is preferably 30 to 300 seconds, more preferably 30 to 180 seconds, and even more preferably 30 to 90 seconds.
For both PB and PEB, the heat treatment can be carried out by means provided in a normal exposure machine or developing machine, and may be carried out using a hot plate or the like.

(Preferred embodiment: immersion exposure)
As a suitable aspect of exposure, for example, liquid immersion exposure can be mentioned. By using immersion exposure, a finer pattern can be formed. Note that immersion exposure can be combined with super-resolution techniques such as a phase shift method and a modified illumination method.

The immersion liquid used for immersion exposure is transparent to the exposure wavelength and has a refractive index temperature coefficient as much as possible so as to minimize distortion of the optical image projected onto the resist film. Small liquids are preferred. In particular, when the exposure light source is 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 as the immersion liquid, 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 film 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, for example, when an opaque material with respect to 193 nm light or an impurity whose refractive index is significantly different from water is mixed, distortion of the optical image projected on the resist is caused. For this reason, 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 water used as the immersion liquid preferably has an electric resistance of 18.3 MΩcm or more, a TOC (organic substance concentration) of 20 ppb or less, and is preferably deaerated.
Moreover, it is possible to improve lithography performance by increasing the refractive index of the immersion liquid. From such a viewpoint, an additive for increasing the refractive index may be added to water, or heavy water (D ₂ O) may be used instead of water.

In immersion exposure, the surface of the resist film may be washed with an aqueous chemical solution before exposure and / or after exposure (before heat treatment).

[Step (3): Development step]
Step (3) is a step of developing the film exposed in step (2) to form a pattern.
Step (3) is a step of developing a film using a developer containing water and then developing using a developer containing an organic solvent to form a pattern, or developing using a developer containing an organic solvent. After that, a pattern is formed by developing using a developer containing water. Hereinafter, development of a film using a developer containing water may be referred to as “Step A”, and development of a film using a developer containing an organic solvent is also referred to as “Step B”.
In other words, the process B may be performed after the process A is performed, or the process A may be performed after the process B is performed. Especially, after implementing the process A, it is preferable to implement the process B.
In step A, the “region with a large amount of exposure” in step (2) is dissolved by the developer to form a so-called positive pattern. On the other hand, in the step B, the “region with a small amount of exposure” in the step (2) is dissolved by the developing solution to form a so-called negative pattern. That is, step A is a step of selectively dissolving and removing a region where the exposure amount is greater than or equal to the threshold value (a), and step B is selectively dissolving and removing a region where the exposure amount is less than the threshold value (b). It is a process of removing. Note that the threshold (a) is larger than the threshold (b) in terms of the magnitude relationship between the threshold (a) and the threshold (b).

Hereinafter, first, the developer used in this step will be described in detail, and the procedure of the subsequent steps will be described in detail.

(Developer)
In step A, a developer containing water is used.
The developer used in step A contains water as a main component. In addition, that water is a main component means that the content of water is more than 50% by mass with respect to the total amount of the developer.
As the developer, it is preferable to use an alkaline aqueous solution containing an alkali from the viewpoint of better pattern solubility.
The type of the alkaline aqueous solution is not particularly limited, and examples thereof include quaternary ammonium salts (for example, tetramethylammonium hydroxide), inorganic alkalis, primary amines, secondary amines, tertiary amines, alcohol amines, cyclic amines, and the like. Examples include alkaline aqueous solutions. Among these, an aqueous solution of a quaternary ammonium salt typified by tetramethylammonium hydroxide is preferable.

Appropriate amounts of alcohols and surfactants can be added to the alkaline aqueous solution. 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 alkali solution is usually 0.1 to 20% by mass.
The pH of the alkaline aqueous solution is usually 10.0 to 15.0.

In step B, a developer containing a soluble solvent (hereinafter also referred to as “organic developer” as appropriate) is used.
The developer used in Step B contains an organic solvent as a main component. In addition, that an organic solvent is a 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. . 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, isoamyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, Diethylene glycol monoethyl 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, propyl lactate Butyl butanoate, methyl 2-hydroxyisobutyrate, isobutyl isobutyrate, butyl propionate and the like.

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, alcohols 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, methoxymethylbuta Glycol ether solvents such Lumpur; and the like.

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 a solvent other than the above 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 in 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 temperature uniformity in the wafer surface is improved. As a result, dimensional uniformity in the wafer surface. Improves.

An appropriate amount of a surfactant can be added to the organic developer as required.
Although it does not specifically limit as surfactant, For example, an ionic or nonionic fluorine type and / or silicon type surfactant etc. 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 US Pat. Nos. 5,360,692, 5,298,881, 5,296,330, 5,346,098, 5,576,143, 5,294,511, and 5,824,451 can be mentioned. 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 addition amount of the surfactant 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.

(Additive)
In the developer, especially the organic developer used in Step B, the resin (A) described above as an additive further includes a polar group generated by the action of an acid, an ionic bond, a hydrogen bond, a chemical bond, and a dipole mutual bond. Compounds that can form at least one of the interactions may be added.
When the resin (A) and this additive form a predetermined interaction, the solubility of the resin (A) is changed, and film slippage is unlikely to occur. In addition, an ionic bond means the electrostatic interaction of a cation and an anion, and salt formation etc. are also included.
Examples of such additives include at least one selected from the group consisting of an onium salt compound, a nitrogen-containing compound, and a phosphorus compound, and more specifically, for example, JP-A-2014-232310. Examples thereof include the additives described in paragraphs <0380> to <0474> of the publication.
When the additive is used, the total mass of the additive in the developer is not particularly limited, but is preferably 0.1 to 5% by mass, more preferably 1 to 5% by mass with respect to the total amount of the developer. It is more preferably 1 to 3% by mass.
In addition, as said additive, only 1 type of compounds may be used and 2 or more types of compounds from which chemical structures differ may be used.

(Development method)
As the developing method in the process A and the process B, for example, a method of immersing the substrate in a tank filled with the developer for a certain time (dip method), and raising the developer on the surface of the substrate by the surface tension and leaving it stationary for a certain time. The developing method (paddle method), the method of spraying the developer on the substrate surface (spray method), the developer is continuously discharged while scanning the developer discharge nozzle at a constant speed on the substrate rotating at a constant speed. A method (dynamic dispensing method) or the like can be applied.
When the various development methods described above include a step of discharging the developer from the developing nozzle of the developing device toward the resist film, the discharge pressure of the discharged developer (the flow rate per unit area of the discharged developer) is As an example, it is preferably 2 mL / sec / mm ² or less, more preferably 1.5 mL / sec / mm ² or less, and still more preferably 1 mL / sec / mm ² or less. Although there is no particular lower limit of the flow rate, 0.2 mL / sec / mm ² or more is preferable in consideration of throughput.
Details of this are described in paragraphs <0022> to <0029> of JP-A-2010-232550.
Moreover, you may implement the process of stopping image development, after substituting with another solvent after the process developed using the developing solution containing an organic solvent.

(Rinse treatment)
After development using the developer, washing may be performed using a rinse solution as necessary.
The rinsing liquid is not particularly limited as long as the resist film is not dissolved. For example, pure water can be used in the process A, and a solution containing a general organic solvent can be used in the process B.
Hereinafter, the rinse liquid in the process B will be described in more detail.

Examples of the rinsing liquid include a rinsing 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. Are preferable.
Here, specific examples of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents include, for example, the organic solvents described as specific examples of the organic developer described above. The same organic solvent is mentioned.

Among these, the rinsing liquid is preferably a rinsing liquid containing a hydrocarbon solvent or an alcohol solvent.

Examples of the hydrocarbon solvent include aliphatic hydrocarbon solvents having 5 or more carbon atoms, such as pentane, hexane, octane, decane, undecane, dodecane, hexadecane, etc., and aliphatic hydrocarbons having 8 or more carbon atoms. Hydrocarbon solvents are preferred, aliphatic hydrocarbon solvents having 10 or more carbon atoms are more preferred, and decane, undecane, and dodecane are even more preferred.
In addition, although the upper limit of the carbon atom number of the said aliphatic hydrocarbon solvent is not specifically limited, For example, 16 or less is mentioned, 14 or less is preferable and 12 or less is more preferable.

The rinsing liquid containing an alcohol solvent is preferably a rinsing liquid containing a monohydric alcohol, and more preferably a rinsing liquid containing a monohydric alcohol having 5 or more carbon atoms.
Examples of the monohydric alcohol include linear, branched, and cyclic monohydric alcohols, and specific examples thereof include 1-hexanol, 2-hexanol, 4-methyl-2-pentanol (methyl). Isobutyl carbinol (MIBC)), 1-pentanol, 3-methyl-1-butanol and the like.
When an ester solvent is used as the rinsing liquid, a glycol ether solvent may be used in addition to the ester solvent (one or more). Specific examples in this case include using an ester solvent (preferably butyl acetate) as a main component and a glycol ether solvent (preferably propylene glycol monomethyl ether (PGME)) as a subcomponent. Thereby, residue defects are suppressed.

The rinse liquid may contain a plurality of solvents. Moreover, the rinse liquid may contain an organic solvent other than the above.

The water content of 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, better development characteristics can be obtained.

The vapor pressure of the rinse liquid is preferably 0.05 kPa or more and 5 kPa or less at 20 ° C., more preferably 0.1 kPa or more and 5 kPa or less, and most preferably 0.12 kPa or more and 3 kPa or less. 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. Specific examples and usage amounts of the surfactant are the same as those of the organic developer described above.

In the rinse treatment, the developed wafer is cleaned using the rinse solution. 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), and the like can be applied. Among these, a method of performing a cleaning process by a spin coating method, rotating the substrate at a rotational speed of 2000 rpm to 4000 rpm after cleaning, and removing the rinse liquid from the substrate is preferable.

In addition, it is preferable to perform heat treatment (post bake) after development using a developer (after rinsing when rinsing is performed). The developer and the rinsing liquid remaining between the patterns and inside the patterns are removed by heat treatment.
As conditions for the heat treatment (Post Bake), the heating temperature is, for example, 40 to 160 ° C., preferably 70 to 140 ° C., and the heating time is, for example, 10 seconds to 3 minutes, and preferably 30 to 90 seconds.

[Step (4): Plasma treatment step]
Step (4) is a step of subjecting the pattern (resist pattern) formed in step (3) to plasma treatment. Thereby, the side wall of the resist pattern becomes smooth and the LWR becomes small.
Step (4) is preferably a step of performing a plasma treatment on the pattern with a plasma generated from a treatment gas containing hydrogen, and an embodiment in which the treatment gas further contains argon is more preferable.
Hereinafter, the plasma processing will be described in more detail.

FIG. 1 is a cross-sectional view schematically showing an example of a processing apparatus used when performing plasma processing.
The processing apparatus 1 is hermetically configured and has a substantially cylindrical chamber 2 into which a substrate W with a resist pattern is carried.
At the bottom of the chamber 2 is provided a stage 4 for mounting a substrate W with a resist pattern, which functions as a lower electrode through a dielectric plate 3 made of ceramics or the like. The stage 4 is made of metal such as aluminum, and has an electrostatic chuck (not shown) for electrostatically adsorbing the substrate W with a resist pattern on the upper surface. A cooling medium flow path (not shown) for cooling the patterned substrate W is provided.

In the upper part of the chamber 2, a shower head 5 that functions as an upper electrode is provided so as to face the stage 4. Thereby, a parallel plate electrode is comprised by the shower head 5 which functions as an upper electrode, and the stage 4 which functions as a lower electrode. The shower head 5 is configured to include silicon or silicon carbide on the surface facing the stage 4, for example, and is connected to a DC negative power source 6. The shower head 5 has a gas introduction port 7 at the top, a gas diffusion space 8 inside, and a plurality of gas discharge holes 9 at the bottom. A gas supply pipe 10 is connected to the gas inlet 7. A processing gas supply system 11 for supplying a processing gas is connected to the other end of the gas supply pipe 10. The processing gas is supplied into the chamber 2 from the processing gas supply system 11 through the gas supply pipe 10 and the shower head 5.

The exhaust pipe 12 is connected to the bottom of the chamber 2. An exhaust mechanism 13 including a vacuum pump and a pressure adjusting valve is connected to the exhaust pipe 12. The inside of the chamber 2 is exhausted by the exhaust mechanism 13 so that the inside of the chamber 2 is maintained at a predetermined degree of vacuum.

For example, two high frequencies are supplied to the stage 4 functioning as the lower electrode. One is a first high frequency having a high frequency suitable for plasma generation, and the other is a second high frequency having a lower frequency than the first high frequency suitable for ion attraction.
The first high frequency is, for example, 10 MHz or more and 100 MHz or less, and the second high frequency is, for example, 15 MHz or less, 0.1 MHz or more. The first high frequency is supplied from the first high frequency power supply 14a to the stage 4 via the matching unit 15a. The second high frequency is supplied from the second high frequency power supply 14b to the stage 4 via the matching unit 15b. The high frequency supplied to the stage 4 is not limited to supplying two high frequencies, and one high frequency, that is, a single frequency may be supplied.

When performing plasma processing using such a processing apparatus 1, first, the substrate W with a resist pattern is transferred into the chamber 2 and placed on the stage 4. Note that the lower layer film and the upper layer film described above may be formed on the substrate W with a resist pattern.
Next, the inside of the chamber 2 is evacuated, and the inside of the chamber 2 is brought into a reduced pressure state. Next, a processing gas is supplied into the chamber 2. Examples of the processing gas include a processing gas containing hydrogen gas (H ₂ ), and a processing gas containing hydrogen gas (H ₂ ) and argon gas (Ar) is preferable.

Next, a high frequency is supplied to the stage 4, a high frequency is supplied between the stage 4 and the shower head 5, and a DC negative voltage is supplied to the shower head 5. An example of the high frequency is 40 MHz as the first high frequency and 13 MHz as the second high frequency.

At the time when the processing gas is supplied into the chamber 2, the processing space defined between the stage 4 and the shower head 5 is in a state where hydrogen gas (H ₂ ) and the like contained in the processing gas are drifting. When a high frequency is supplied between the stage 4 and the shower head 5 in such a state, plasma is generated, and hydrogen molecules floating in the processing space are separated into hydrogen molecules to become hydrogen radicals.
Further, when the processing gas contains argon gas, argon ions (Ar ⁺ ) are generated. When a DC negative voltage is supplied to the shower head 5 in this state, argon ions, which are positive charges, fly toward the shower head 5, hit the shower head 5, and silicon contained in the surface of the shower head 5 facing the stage 4. (Si) is sputtered, and silicon (e ⁻ ) is emitted at the same time as silicon is knocked into the processing space.

Thus, it is considered that the hydrogen radical reacts with the resist pattern or the resist pattern is irradiated with the electron beam, thereby smoothing the side wall of the resist pattern and reducing the LWR.

The conditions for the plasma treatment are appropriately set according to the processing gas used.
For example, when a processing gas containing hydrogen gas (H ₂ ) and argon gas (Ar) is used as the processing gas, an example of the flow rate ratio is H ₂ : Ar = 450 ml / min: 450 ml / min. An example of the pressure in the chamber 2 after supplying the processing gas is 13.3 Pa. An example of the high frequency power is 500 W as the first high frequency and 0 W as the second high frequency. An example of the DC negative voltage is -450V. An example of the processing time is 25 seconds.

When a processing gas containing hydrogen gas (H ₂ ), carbon tetrafluoride gas (CF ₄ ), and argon gas (Ar) is used as the processing gas, an example of the flow rate ratio is H ₂ : CF ₄ : Ar = 100 ml / min: 40 ml / min: 800 ml / min. Moreover, an example of the pressure in the chamber 2 after supplying the processing gas is 6.7 Pa. An example of the high frequency power is 300 W as the first high frequency and 0 W as the second high frequency. An example of the DC negative voltage is -900V. An example of the processing time is 30 seconds.

The pattern obtained by the pattern forming method of the present invention is generally suitably used as an etching mask for a semiconductor device or the like, but can also be used for other purposes. Other uses include, for example, guide pattern formation in DSA (Directed Self-Assembly) (see, for example, ACS Nano Vol. 4, No. 8, Page 4815-4823), use as a core material (core) of a so-called spacer process (for example, JP-A-3-270227, JP-A-2013-164509, etc.).

In the present invention, a technique of double patterning (see, for example, JP-A-2009-088085) such as SADP (Spacer Doubled Patterning) may be applied.
Actinic ray-sensitive or radiation-sensitive resin composition used in the pattern forming method of the present invention and various materials (for example, resist solvent, developer, rinse solution, antireflection film forming composition, top coat forming) The composition or the like preferably does not contain impurities such as metals. The content of impurities contained in these materials is preferably 1 ppm or less, more preferably 10 ppb or less, still more preferably 100 ppt or less, particularly preferably 10 ppt or less, and substantially free (below the detection limit of the measuring device). Is most preferable.
Examples of a method for removing impurities such as metals from the various materials include filtration using a filter. The pore size of the filter is preferably 10 nm or less, more preferably 5 nm or less, and still more preferably 3 nm or less. As a material of the filter, a filter made of polytetrafluoroethylene, polyethylene, or nylon is preferable. The filter may be a composite material obtained by combining these materials and ion exchange media. A filter that has been washed in advance with an organic solvent may be used. In the filter filtration step, a plurality of types of filters may be connected in series or in parallel. When a plurality of types of filters are used, filters having different pore diameters and / or materials may be used in combination. Moreover, various materials may be filtered a plurality of times, and the step of filtering a plurality of times may be a circulating filtration step.
Moreover, as a method for reducing impurities such as metals contained in the various materials, a raw material having a low metal content is selected as a raw material constituting the various materials, and filter filtration is performed on the raw materials constituting the various materials. For example, the inside of the apparatus may be lined with Teflon (registered trademark), and distillation may be performed under a condition in which contamination is suppressed as much as possible. The preferable conditions for filter filtration performed on the raw materials constituting the various materials are the same as those described above.

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 (Office Automation) related equipment, media related equipment, optical equipment, communication equipment, etc.).

Examples are shown below, but the present invention is not limited thereto.

<Preparation of composition for forming resist film>
Each component shown in the following Table 1 was dissolved in each solvent shown in the same table to prepare each resist film forming composition.

The various components used in Table 1 above are summarized below.

In Table 2 above, the composition ratio (molar ratio) indicates the molar ratio of the repeating units contained in the resins P-1 to P-33 and RP-1 to RP-2, and the repeating units in the chemical formula shown above. The composition ratios are shown in order from the left.

In Table 3 above, the composition ratio (molar ratio) indicates the molar ratio of the repeating units contained in the resins N-1 to N-7, and the composition ratio of the repeating units in the chemical formula shown above is shown in order from the left. .

The following were used as the solvent.
SL-1: Propylene glycol monomethyl ether acetate (PGMEA)
SL-2: Propylene glycol monomethyl ether (PGME)
SL-3: cyclohexanone SL-4: γ-butyrolactone SL-5: propion carbonate

<Preparation of composition for forming upper layer film>
The components shown in Table 4 below were dissolved in the solvents shown in the same table to prepare an upper layer film-forming composition.

The various components used in Table 4 above are summarized below.

In Table 5 above, the composition ratio (molar ratio) indicates the molar ratio of the repeating units contained in the resins TP-1 to TP-5, and the composition ratio of the repeating units in the chemical formula shown above is shown in order from the left. .

The following were used as the solvent.
MIBC: Methyl isobutyl carbinol (4-methyl-2-pentanol)
BuOH: n-butanol IAE: isoamyl ether IBIB: isobutyl isobutyrate

<Examples 1 to 34 and Comparative Examples 1 and 2>
On the silicon wafer, the lower layer film shown in Table 6 below was formed. A resist film forming composition shown in the table was applied thereon, and baked under PB (Prebake) conditions shown in the table. As a result, a resist film having the thickness shown in the table was formed.
In Examples 24 to 30, the upper layer film-forming composition shown in Table 6 below was further applied onto the resist film, and baked under the PB (Prebake) conditions shown in the same table, so that the film thickness was 90 nm. An upper layer film was formed.

Next, an ArF excimer laser immersion scanner (SMTL XT1700i, NA1.20, Dipole, outer sigma 0.95, inner sigma 0.7) is used for the obtained resist film (and upper layer film). Pattern exposure was performed. As the reticle, a mask with a half pitch of 48 nm line and space 1: 1 was used. Moreover, ultrapure water was used as the immersion liquid.
Thereafter, the resist film was baked under PEB (Post Exposure Bake) conditions shown in Table 6 below, and the resist film after baking was cooled to room temperature. In Examples 24 to 25 and 27 to 30, the upper film was peeled off using the upper film peeling solvent shown in the same table.
Next, development was performed using the first developer shown in Table 6 below for the development time shown in the same table, and rinsing was performed for 30 seconds with the first rinse liquid shown in the same table except Example 33. Then, it baked on PB (Post Bake) conditions shown in the same table.
Next, development was performed using the second developer shown in Table 6 for the development time shown in the table, and Examples 10, 14, and 34 were rinsed with the second rinse solution shown in the table for 30 seconds. Then, it baked on PB (Post Bake) conditions shown in the same table.
Thereby, a line and space pattern with a half pitch of 24 nm was formed (a substrate W with a resist pattern was obtained).

Next, plasma processing was performed on the resist pattern (line and space pattern) of the obtained substrate W with a resist pattern using the processing apparatus 1 described with reference to FIG.
More specifically, first, a silicon wafer with a resist pattern (substrate W with a resist pattern) was transferred into the chamber 2 and placed on the stage 4. Next, after the chamber 2 was evacuated to a reduced pressure state, the processing gas was supplied into the chamber 2.
As the processing gas, a processing gas containing hydrogen gas (H ₂ ), carbon tetrafluoride gas (CF ₄ ), and argon gas (Ar) was used. The flow rate ratio of the processing gas was H ₂ : CF ₄ : Ar = 100 ml / min: 40 ml / min: 800 ml / min. Moreover, the pressure in the chamber 2 after supplying the processing gas was set to 6.7 Pa.
Next, a high frequency was supplied to the stage 4, and a high frequency was supplied between the stage 4 and the shower head 5, and a negative DC voltage was supplied to the shower head 5 to generate plasma. At this time, the high frequency was set to the first high frequency: 40 MHz and the second high frequency: 13 MHz. The high frequency power was set to the first high frequency: 300 W and the second high frequency: 0 W. The negative DC voltage was −900V. The processing time was 30 minutes.

<LWR (Line Width Roughness)>
Optimum exposure amount that the line width of the space formed by negative development using an organic developer is the same as the line width of a space formed by positive development using a developer containing water (Eop), and the resist pattern formed by the above Eop was observed using a length measurement scanning electron microscope (SEM; Hitachi, Ltd., CG-4100). With respect to the range of 2 μm in the longitudinal direction of the space pattern, 50 line widths were measured at equal intervals, and 3σ was calculated from the standard deviation. The results are shown in Table 6 below. A smaller value indicates better performance.
The LWR was evaluated after development (before the plasma processing) and after the plasma processing, and the improvement rate (unit:%) indicating how much the LWR was improved by the plasma processing was also evaluated.

The lower layer films shown in Table 6 are as follows.
SOC: Brewer spin-on carbon material (film thickness 120nm)
SOG: Brewer spin-on-glass material (film thickness 30 nm)
BARC-A: Brewer's organic antireflection film (film thickness: 80 nm)
BARC-B: Nissan Chemical Organic Antireflective Film (film thickness 30nm)
SiON: Silicon nitride oxide vapor deposition film (film thickness: 15 nm)
SOC, SOG, BARC-A and BARC-B were formed by baking at 205 ° C. for 60 seconds after coating by a spin coating method.
In Table 6, when a plurality of lower layer films are described, they are described in order from the side closer to the substrate.

Of the developers shown in Table 6, “2.38% TMAH” means “2.38 mass% TMAH (tetramethylammonium hydroxide) aqueous solution”, and “0.24% TMAH” and “1” .19% TMAH "means" 0.24 mass% TMAH aqueous solution "and" 1.19 mass% TMAH aqueous solution ".

As is apparent from the results shown in Table 6 above, Examples 1-34 in which the weight average molecular weight of the acid-decomposable resin contained in the resist film forming composition is 5,000 or more have a weight average molecular weight of 5, It was found that the LWR after the plasma treatment was smaller than those of Comparative Examples 1 and 2 that were less than 000.
Further, when Examples 1 to 4 using the acid decomposable resins P-1 to P-4 having the same repeating unit and the same composition ratio are compared, the LWR is better as the weight average molecular weight of the acid decomposable resin is larger. I found out that

Next, using the patterns obtained in Examples 1 to 6 and 9 to 34 as a mask, a composite film of SOG and BARC-B (or a composite film of SiON and BARC-B) is converted into a CF-based gas (four fluorine). The SOC was etched by plasma etching using oxygen gas plasma using the composite film as a mask.
Next, a SiO ₂ film was formed on the surface of the obtained SOC pattern by a CVD (Chemical Vapor Deposition) method. Furthermore the CF-based gas, a SiO ₂ film was etched to a state in which the SiO ₂ film remained only on the side wall portion of the SOC pattern.
Next, the SOC pattern was removed by etching using oxygen gas plasma to obtain a pattern made of the SiO ₂ film remaining on the side wall, and a line and space pattern with a half pitch of 12 nm was obtained.
When the LWR of this pattern was evaluated in the same manner as described above, each example shows a value obtained by transferring the LWR after the plasma treatment, and an example in which the weight-average molecular weight of the acid-decomposable resin is large and the effect of improving the LWR by smoothing is large. It was found that the pattern after the SiO ₂ film transfer is also effective.

DESCRIPTION OF SYMBOLS 1 Processing apparatus 2 Chamber 3 Dielectric board 4 Stage 5 Shower head 6 Negative power supply 7 Gas introduction port 8 Gas diffusion space 9 Gas protrusion 10 Gas supply piping 11 Process gas supply system 12 Exhaust pipe 13 Exhaust mechanism 14a 1st high frequency power supply 15a Matching device 14b Second high frequency power supply 15b Matching device W Substrate with resist pattern

Claims

Step 1 of forming a film on a substrate using an actinic ray-sensitive or radiation-sensitive resin composition containing at least a resin having a group that decomposes by the action of an acid to generate a polar group;
Step 2 of exposing the film;
Developing the exposed film to form a pattern,
And a step 4 of performing a plasma treatment on the pattern,
Step 3 is a step of developing a film using a developer containing water and then developing the film using a developer containing an organic solvent to form a pattern, or using a developer containing an organic solvent. After the film is developed, the film is developed using a developer containing water to form a pattern,
The pattern formation method whose weight average molecular weights of the said resin are 5,000 or more.
The pattern forming method according to claim 1, wherein the step 4 is a step of performing plasma processing on the pattern by plasma generated from a processing gas containing hydrogen.
The pattern forming method according to claim 2, wherein the processing gas further contains argon.
The pattern forming method according to any one of claims 1 to 3, wherein the polar group is a carboxyl group.
The resin includes a repeating unit having a group that decomposes by the action of an acid to generate a polar group, and the content of the repeating unit is 35 mol% or more based on all the repeating units of the resin. 5. The pattern forming method according to any one of 1 to 4.
The pattern formation according to any one of claims 1 to 5, wherein the resin further has at least one structure selected from the group consisting of a lactone structure, a sultone structure, a cyclic ketone structure, and a cyclic sulfone structure. Method.
An electronic device manufacturing method comprising the pattern forming method according to any one of claims 1 to 6.