Pattern formation method, method for manufacturing electronic devices, photosensitive or radiation-sensitive resin composition, resist film

Abstract

The present invention addresses the problem of providing a pattern forming method by which a pattern having excellent defect suppressing properties can be formed. Moreover, the present invention also addresses the problem of providing an electronic device manufacturing method, an actinic ray-sensitive or radiation-sensitive resin composition, and a resist film.　A pattern forming method according to the present invention comprises: step 1 for forming a resist film having a film thickness of at least 500 nm by using an actinic ray-sensitive or radiation-sensitive resin composition; step 2 for subjecting the resist film to liquid immersion exposure with radiation or actinic rays having a wavelength of at most 200 nm and heat-treating the resist film; and step 3 for developing the exposed resist film with an alkaline developing agent to form a pattern. The actinic ray-sensitive or radiation-sensitive resin composition contains the following components: (A) a resin having a hydrophilic group and an acid-labile group and having a weight-average molecular weight of at most 8,000; (B) a photoacid generator; (C) a compound having a fluorine atom or a silicon atom and having a group that generates a polar group via the action of an acid or a group that generates a polar group via the action of an alkali; and (D) a solvent, wherein the amount of the solid content in the actinic ray-sensitive or radiation-sensitive resin composition is at least 10.0 mass%.

Description

[Technical Field]

[0001] The present invention relates to a pattern forming method, a method for manufacturing an electronic device, a photosensitive or radiation-sensitive resin composition, and a resist film. [Background technology]

[0002] Since the development of resists for KrF excimer lasers (248 nm), pattern formation methods utilizing chemical amplification have been employed to compensate for the decrease in sensitivity due to light absorption. For example, in a positive-type chemical amplification method, first, the photoacid generator contained in the exposure area decomposes upon light irradiation to generate acid. Then, during the post-exposure bake (PEB) process, the generated acid acts as a catalyst to change the alkali-insoluble groups of the resin contained in the photosensitive or radiation-sensitive resin composition to alkali-soluble groups, thereby changing the solubility in the developer. Subsequently, development is performed using, for example, a basic aqueous solution. This removes the exposure area and obtains the desired pattern. To miniaturize semiconductor devices, the wavelength of exposure light sources has been shortened and the numerical aperture (NA) of projection lenses has been increased. Currently, exposure machines using ArF excimer lasers with a wavelength of 193 nm as the light source have been developed. Under these circumstances, various compositions have been proposed for photosensitive or radiation-sensitive resin compositions.

[0003] For example, Patent Document 1 discloses a positive-type photosensitive resin composition suitable for microfabrication of semiconductor devices using an ArF excimer laser. In particular, the examples section of Patent Document 1 describes the formation of a thick resist film with a thickness of 500 nm. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2000-066398 [Overview of the project] [Problems that the invention aims to solve]

[0005] The present inventors investigated the positive-type photosensitive resin composition described in Patent Document 1 and found that when ArF immersion lithography was performed on a resist film with a thickness of 500 nm or more formed from the above-mentioned positive-type photosensitive resin composition, many defects occurred in the formed pattern. In other words, it was revealed that there is room to further improve the defect suppression of the pattern.

[0006] Therefore, the object of the present invention is to provide a pattern forming method that can form a pattern with excellent defect suppression properties. Furthermore, the present invention also aims to provide a method for manufacturing electronic devices, a photosensitive or radiation-sensitive resin composition, and a resist film. [Means for solving the problem]

[0007] The inventors have found that the above problems can be solved by the following configuration.

[0008] [1] Step 1 of forming a resist film with a thickness of 500 nm or more using a photosensitive or radiation-sensitive resin composition, Step 2 involves immersion exposure of the above-mentioned resist film with radiation or active light of a wavelength of 200 nm or less, followed by a heat treatment. A pattern forming method comprising step 3 of developing the exposed resist film with an alkaline developer to form a pattern, The above-mentioned photosensitive or radiation-sensitive resin composition contains the components shown in (A) to (D) below, (A) A resin having hydrophilic groups and acid-degradable groups, with a weight-average molecular weight of 8,000 or less. (B) Photoacid generator (C) Compounds having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali. (D) Solvent and, A pattern-forming method wherein the solid content in the above-mentioned photosensitive or radiation-sensitive resin composition is 10.0% by mass or more. [2] The pattern-forming method according to [1], wherein the compound shown in (C) above includes a repeating unit X having a group that generates a polar group upon the action of an acid or a group that generates a polar group upon the action of an alkali. [3] The pattern formation method according to [2], wherein the repeating unit X is a repeating unit represented by formula (II) or formula (III) described later. [4] The pattern forming method according to any one of [1] to [3], wherein the compound shown in (C) above satisfies either requirement 1 or requirement 2 below. Requirement 1: If the above compound has a group that generates a polar group upon the action of an acid, when a film made of the above compound is subjected to full-surface exposure under the same exposure conditions as in step 2 and then heat-treated, the difference between the water contact angle of the surface of the film made of the above compound before full-surface exposure and the water contact angle of the surface of the film made of the above compound after the heat-treated film must be 10° or more. Requirement 2: If the above compound has a group that generates a polar group under the action of alkali, when the film made of the above compound is brought into contact with the alkaline developer used in step 3, the difference between the water contact angle of the surface of the film made of the above compound before contact with the alkaline developer and the water contact angle of the surface of the film made of the above compound after contact with the alkaline developer must be 10° or more. [5] The pattern forming method according to any one of [1] to [4], wherein the resin shown in (A) above contains two or more repeating units having hydrophilic groups, and at least two of the two or more repeating units have hydrophilic groups that are different from each other. [6] The pattern forming method according to any one of [1] to [5], wherein the resin shown in (A) above comprises one or more repeating units having a carboxyl group and one or more repeating units having a hydroxyl group. [7] The pattern forming method according to any one of [1] to [6], wherein the acid-degradable group of the resin shown in (A) above has a structure in which a polar group is protected by a leaving group that is removed by the action of an acid, and the number of carbon atoms of the leaving group is 8 or more. [8] The pattern forming method according to any one of [1] to [7], wherein the photoacid generator shown in (B) above includes a compound represented by formula (ZI-3) or a compound represented by formula (ZI-4) described later. [9] The pattern-forming method according to any one of [1] to [8], wherein the above-mentioned photosensitive or radiation-sensitive resin composition further comprises the compound shown in (E) below. (E) Acid diffusion control agents that do not have basic properties

[10] The resin shown in (A) above does not contain fluorine atoms and silicon atoms, and the pattern forming method according to any one of [1] to [9].

[11] The pattern forming method according to any one of [1] to

[10] , wherein the content of the component shown in (C) above is 10.0% by mass or less with respect to the total solid content of the composition.

[12] A method for manufacturing an electronic device, comprising the pattern formation method described in any of [1] to

[11] .

[13] A photosensitive or radiation-sensitive resin composition containing the components shown in (A) to (D) below, and having a solid content of 10.0% by mass or more. (A) A resin having hydrophilic groups and acid-degradable groups, with a weight-average molecular weight of 8,000 or less. (B) Photoacid generator (C) Compounds having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali. (D) Solvent

[14] The photosensitive or radiation-sensitive resin composition according to

[13] , wherein the compound shown in (C) above contains a repeating unit X having a group that generates a polar group by the action of an acid or a group that generates a polar group by the action of an alkali.

[15] The photosensitive or radiation-sensitive resin composition according to

[14] , wherein the repeating unit X is a repeating unit represented by formula (II) or formula (III) described later.

[16] The photosensitive or radiation-sensitive resin composition according to any of

[13] to

[15] , wherein the compound shown in (C) above satisfies requirement 1 or requirement 2 below. Requirement 1: If the above compound has a group that generates a polar group upon the action of an acid, when a film made of the above compound is subjected to full-surface exposure under the same exposure conditions as in step 2 and then heat-treated, the difference between the water contact angle of the surface of the film made of the above compound before full-surface exposure and the water contact angle of the surface of the film made of the above compound after the heat-treated film must be 10° or more. Requirement 2: If the above compound has a group that generates a polar group under the action of alkali, when the film made of the above compound is brought into contact with the alkaline developer used in step 3, the difference between the water contact angle of the surface of the film made of the above compound before contact with the alkaline developer and the water contact angle of the surface of the film made of the above compound after contact with the alkaline developer must be 10° or more.

[17] The resin shown in (A) above comprises two or more repeating units having hydrophilic groups, and at least two of the two or more repeating units have different hydrophilic groups, as described in any of

[13] to

[16] .

[18] The resin shown in (A) above comprises one or more repeating units having a carboxyl group and one or more repeating units having a hydroxyl group, as described in any of

[13] to

[17] , a photosensitive or radiation-sensitive resin composition.

[19] The acid-degradable group of the resin shown in (A) above has a structure in which a polar group is protected by a leaving group that is removed by the action of an acid, and the number of carbon atoms of the leaving group is 8 or more, the photosensitive or radiation-sensitive resin composition according to any one of

[13] to

[18] .

[20] The photoacid generator shown in (B) above comprises a compound represented by formula (ZI-3) or a compound represented by formula (ZI-4) described later, as described later, according to any of

[13] to

[19] .

[21] A photosensitive or radiation-sensitive resin composition according to any one of

[13] to

[20] , further comprising the compound shown in (E) below. (E) Acid diffusion control agents that do not have basic properties

[22] The resin shown in (A) above is a photosensitive or radiation-sensitive resin composition according to any one of

[13] to

[21] , which does not contain fluorine atoms or silicon atoms.

[23] The photosensitive or radiation-sensitive resin composition according to any one of

[13] to

[22] , wherein the content of the component shown in (C) above is 10.0% by mass or less with respect to the total solid content of the composition.

[24] A resist film formed using a photosensitive or radiation-sensitive resin composition described in any of

[13] to

[23] . [Effects of the Invention]

[0009] According to the present invention, a pattern forming method is provided that can form a pattern with excellent defect suppression properties. Furthermore, according to the present invention, a method for manufacturing electronic devices, a photosensitive or radiation-sensitive resin composition, and a resist film can also be provided. [Modes for carrying out the invention]

[0010] The present invention will be described in detail below. The following description of the constituent elements may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, regarding the notation of groups (atomic groups), unless contrary to the spirit of the present invention, notations that do not specify substituted or unsubstituted include both substituted and unsubstituted groups. For example, "alkyl group" includes not only unsubstituted alkyl groups but also substituted alkyl groups. Furthermore, in this specification, "organic group" means a group containing at least one carbon atom. Unless otherwise specified, the substituents are preferably monovalent. In this specification, "active light" or "radiation" means, for example, the emission spectrum of a mercury lamp, far ultraviolet light represented by an excimer laser, extreme ultraviolet light (EUV light), X-rays, and electron beams (EB). In this specification, "light" means active light or radiation. In this specification, "exposure" includes not only exposure with emission line spectra from mercury lamps, far ultraviolet light represented by excimer lasers, extreme ultraviolet light, X-rays, and EUV light, but also drawing with particle beams such as electron beams and ion beams, unless otherwise specified. In this specification, "~" is used to mean that the numbers before and after it are included as the lower and upper limits, respectively. The bonding direction of divalent groups as expressed herein is not limited unless otherwise specified. For example, in a compound represented by the formula "XYZ", if Y is -COO-, Y may also be -CO-O- or -O-CO-. Furthermore, the above compound may also be "X-CO-OZ" or "XO-CO-Z".

[0011] In this specification, (meth)acrylate refers to acrylate and methacrylate, and (meth)acrylic refers to acrylic and methacrylic. In this specification, the weight-average molecular weight (Mw), number-average molecular weight (Mn), and degree of dispersion (also called molecular weight distribution) (Mw / Mn) of a resin are defined as polystyrene-converted values ​​obtained by GPC (Gel Permeation Chromatography) measurement using a GPC (Gel Permeation Chromatography) instrument (Tosoh HLC-8120GPC) (solvent: tetrahydrofuran, flow rate (sample injection volume): 10 μL, column: Tosoh TSK gel Multipore HXL-M, column temperature: 40°C, flow rate: 1.0 mL / min, detector: differential refractive index detector).

[0012] In this specification, the acid dissociation constant (pKa) refers to the pKa in aqueous solution, and specifically, it is a value calculated using the software package 1 described below, based on a database of Hammett substituent constants and known literature values. All pKa values ​​described herein are those calculated using this software package.

[0013] Software Package 1: Advanced Chemistry Development (ACD / Labs) Software V8.14 for Solaris (1994-2007 ACD / Labs).

[0014] On the other hand, pKa can also be determined by molecular orbital calculations. Specifically, this method involves calculating the H₂ in aqueous solution based on the thermodynamic cycle. + One method is to calculate it by calculating the dissociation free energy. + The dissociation free energy can be calculated using, for example, DFT (Density Functional Theory), but various other methods have been reported in the literature and are not limited to this. Several software programs exist that can perform DFT; for example, Gaussian16 is one such program.

[0015] In this specification, pKa refers to a value calculated using software package 1 based on a database of Hammett substituent constants and publicly available literature values, as described above. However, if pKa cannot be calculated using this method, the value obtained by Gaussian16 based on DFT (Density Functional Theory) shall be adopted. Furthermore, as stated above, pKa refers to "pKa in aqueous solution," but if pKa in aqueous solution cannot be calculated, "pKa in dimethyl sulfoxide (DMSO) solution" shall be used.

[0016] In this specification, "solids" means all components in the composition other than the solvent. Furthermore, "amount of solids" means the amount (by mass) of the solids in the composition.

[0017] In this specification, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms.

[0018] [Pattern formation method] The pattern forming method of the present invention comprises the following steps 1 to 3. Step 1: A step of forming a resist film with a thickness of 500 nm or more using a photosensitive or radiation-sensitive resin composition (hereinafter also referred to as "resist composition") as described later. Step 2: The resist film is subjected to immersion exposure with radiation or active light with a wavelength of 200 nm or less, followed by a heat treatment. Step 3: Develop the exposed resist film with an alkaline developer to form a pattern. Furthermore, the resist composition used in the pattern formation method of the present invention contains the components shown in (A) to (D) below, and has a solid content of 10.0% by mass or more. (A) A resin having hydrophilic groups and acid-degradable groups, and having a weight-average molecular weight of 8,000 or less (hereinafter also referred to as "specific acid-degradable resin"). (B) Photoacid generator (C) Compounds having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali (hereinafter also referred to as "specific polarity conversion compounds"). (D) Solvent

[0019] According to the pattern formation method of the present invention with the above configuration, even when immersion lithography is performed on a thick resist film with a thickness of 500 nm or more using radiation or active light with a wavelength of 200 nm or less, it is possible to form a pattern in which defect generation is suppressed (excellent defect suppression).

[0020] Although this is not entirely clear, the inventors speculate the following: One of the distinctive features of the present invention is that the resist composition contains a specific acid-degradable resin and a specific polarity-converting compound. The mechanism of action of the present invention, involving the specific acid-degradable resin and the specific polarity-converting compound, will be described below. Because specific acid-degradable resins have hydrophilic groups and a small weight-average molecular weight, they are easily dissolved and removed during alkaline development. As a result, it is presumed that the resulting patterns are less prone to development residue defects caused by the acid-degradable resin remaining as an insoluble component. Furthermore, patterns formed with specific acid-degradable resins tend to adopt a close-packed structure, with hydrophilic groups more likely to protrude to the surface, compared to patterns formed with acid-degradable resins that have hydrophilic groups and a relatively large weight-average molecular weight. Since the substrates used for pattern formation are generally relatively hydrophilic, they have excellent affinity with the hydrophilic groups protruding from the pattern. As a result, adhesion between the pattern and the substrate is excellent, and it is presumed that the resulting patterns are less prone to defects caused by peeling or cracking. On the other hand, due to their hydrophilic groups, specific acid-degradable resins tend to have poor conformability to the immersion liquid during immersion lithography using radiation or active light with wavelengths of 200 nm or less. In contrast, it is presumed that the resist composition compensates for this by containing specific polarity conversion compounds, thus improving conformability to the immersion liquid. Specifically, due to its structure containing fluorine and / or silicon atoms, the specific polarity conversion compound is likely to exist on the film surface of the resist film, forming a relatively hydrophobic layer on the surface of the resist film. As a result, the ability to follow the immersion liquid during immersion lithography is improved. In particular, the specific polarity conversion compound can control the water contact angle only on the film surface of the resist film without hindering the effect of improving adhesion between the pattern and the substrate caused by the specific acid-degradable resin. Based on the above mechanism of action, it is presumed that the pattern formation method of the present invention suppresses defects mainly caused by development residue, watermark defects caused by insufficient ability to follow the immersion liquid, and defects caused by peeling between the substrate and the pattern or cracks in the pattern during immersion lithography using radiation or active light with a wavelength of 200 nm or less.

[0021] Furthermore, if the specific polarity conversion compound is a compound having a group that generates a polar group under the action of an acid, the acid generated from the photoacid generator (component C) during the heat treatment performed in step 2 generates a polar group, improving the suitability for alkaline development. Also, if the specific polarity conversion compound is a compound having a group that generates a polar group under the action of an alkali, the action of the alkaline developer in step 3 generates a polar group, improving the suitability for alkaline development. For this reason, the resist composition used in the pattern formation method of the present invention has both suitability for immersion exposure lithography using radiation or active light with a wavelength of 200 nm or less, and suitability for alkaline development treatment. Therefore, in the pattern formation method of the present invention, both immersion exposure treatment using radiation or active light with a wavelength of 200 nm or less and alkaline development treatment can proceed appropriately.

[0022] Furthermore, the resist composition used in the pattern formation method of the present invention has a solid content of 10.0% by mass or more (in other words, the solid content relative to the total mass of the composition), making it suitable for forming thick resist films with a thickness of 500 μm or more.

[0023] In the following, the phrase "better effects of the present invention" may be used to describe a pattern that is more superior in defect suppression performance.

[0024] The pattern formation method of the present invention will be described below. First, the resist composition used in the pattern formation method of the present invention will be described, and then each step of the pattern formation method will be described.

[0025] [Resist composition] The resist composition will be described in detail below. The resist composition is preferably a positive-type resist composition that can be developed with alkali. Furthermore, the resist composition is typically a chemically amplified resist composition.

[0026] The resist composition contains the components shown in (A) to (D) below. Furthermore, the solid content in the resist composition is 10.0% by mass or more. (A) A resin having hydrophilic groups and acid-degradable groups, with a weight-average molecular weight of 8,000 or less. (B) Photoacid generator (C) Compounds having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali. (D) Solvent

[0027] Furthermore, the resist composition may contain other components in addition to the components (A) to (D) described above. Examples of other components that can be preferably used include the components (E) to (F) listed below. (E) Acid diffusion control agent (preferably an acid diffusion control agent that does not have basic properties) (F) Surfactants Below, we will first describe in detail the various components of the resist composition.

[0028] <<(A) Component (specific acid-decomposable resin)>> The resist composition contains a resin (specific acid-degradable resin) having hydrophilic groups and acid-degradable groups, and having a weight-average molecular weight of 8,000 or less.

[0029] An acid-degradable group is a group that decomposes (including elimination) upon the action of an acid to produce a polar group. In particular, it is preferable that the polar group has a structure in which it is protected by a leaving group that is eliminated by the action of an acid. Specific examples of acid-degradable groups will be described later. The specific acid-degradable resin corresponds to a resin that, by containing the above-mentioned acid-degradable group, decomposes under the action of acid and increases in polarity. In other words, in the pattern forming method of the present invention, when an alkaline developer is used as the developer, a positive-type pattern can be suitably formed. Furthermore, as will be described later, it is preferable that the specific acid-degradable resin contains repeating units having acid-degradable groups. Specific embodiments of the repeating units having acid-degradable groups will be described in a later section.

[0030] Examples of hydrophilic groups include hydroxyl groups, cyano groups, alkoxy groups, carboxyl groups, amino groups, and fluorinated alcohol groups, with hydroxyl groups or carboxyl groups being preferred. Furthermore, it is preferable that the specific acid-degradable resin contains repeating units having hydrophilic groups. The specific acid-degradable resin may contain only one type of repeating unit having a hydrophilic group, or it may contain two or more types. In particular, it is preferable that the specific acid-degradable resin contains two to three types of repeating units having a hydrophilic group, as this provides superior effects of the present invention. Furthermore, as a specific acid-degradable resin, it is preferable that it contains two or more repeating units having hydrophilic groups, in order to achieve superior effects of the present invention, and more preferably that it contains two or more repeating units having hydrophilic groups, and that at least two of these two or more repeating units have different hydrophilic groups, and even more preferably that it contains one or more repeating units having carboxyl groups and one or more repeating units having hydroxyl groups. The content of repeating units having hydrophilic groups is preferably 1 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, relative to the total repeating units in the specific acid-degradable resin. Furthermore, the upper limit is preferably 50 mol% or less, more preferably 40 mol% or less, and even more preferably 35 mol% or less. Furthermore, the term "repeating unit having a hydrophilic group" refers to each repeating unit contained in a specific acid-degradable resin that contains a hydrophilic group. Therefore, for example, if a repeating unit having an acid-degradable group (described later) contains a hydrophilic group, then this repeating unit having an acid-degradable group also falls under the category of a repeating unit having a hydrophilic group.

[0031] The weight-average molecular weight of the specific acid-degradable resin is 8,000 or less, calculated as polystyrene equivalent by the GPC method. Preferably, it is 1,000 to 8,000, more preferably 3,000 to 8,000, even more preferably 5,000 to 8,000, and particularly preferably 6,500 to 8,000, as this improves film-forming properties. The degree of dispersion (molecular weight distribution) of the specific acid-degradable resin is typically 1.0 to 5.0, preferably 1.0 to 3.0, more preferably 1.2 to 3.0, and even more preferably 1.2 to 2.0. A lower degree of dispersion results in better resolution and resist shape, smoother sidewalls of the resist pattern, and superior roughness.

[0032] The following describes preferred embodiments of specific acid-degradable resins.

[0033] <Acid-degradable groups and repeating units having acid-degradable groups> An acid-degradable group is a group that decomposes upon the action of an acid to produce a polar group, and among these, it is preferable that the polar group is protected by a leaving group that is removed upon the action of an acid. Furthermore, in a specific acid-degradable resin, it is preferable that the above-mentioned acid-degradable group is contained in the repeating unit. That is, it is preferable that the specific acid-degradable resin contains a repeating unit having an acid-degradable group. When a specific acid-degradable resin contains a repeating unit having an acid-degradable group, its polarity increases upon the action of an acid, increasing its solubility in alkaline developers and decreasing its solubility in organic solvents.

[0034] As repeating units having acid-degradable groups, the repeating units listed in (Repeating units having acid-degradable groups) described later, or the repeating units listed in (Repeating units having acid-degradable groups containing unsaturated bonds) are preferred.

[0035] (Repeating unit with acid-degradable group) An acid-degradable group is a group that decomposes upon the action of an acid to produce a polar group. Preferably, an acid-degradable group has a structure in which the polar group is protected by a leaving group that is removed upon the action of an acid. Preferred polar groups are alkali-soluble groups, such as carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups, sulfonic acid groups, phosphoric acid groups, sulfonamide groups, sulfonylimide groups, (alkylsulfonyl)(alkylcarbonyl)methylene groups, (alkylsulfonyl)(alkylcarbonyl)imide groups, bis(alkylcarbonyl)methylene groups, bis(alkylcarbonyl)imide groups, bis(alkylsulfonyl)methylene groups, bis(alkylsulfonyl)imide groups, tris(alkylcarbonyl)methylene groups, and tris(alkylsulfonyl)methylene groups, as well as alcoholic hydroxyl groups. Among these, carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol groups), or sulfonic acid groups are preferred as polar groups.

[0036] Examples of leaving groups that are removed by the action of an acid include the groups represented by formulas (Y1) to (Y4). Formula (Y1):-C(Rx1)(Rx2)(Rx3) Formula (Y2):-C(=O)OC(Rx1)(Rx2)(Rx3) Formula (Y3):-C(R 36 )(R 37 )(OR 38 ) Formula (Y4):-C(Rn)(H)(Ar)

[0037] In formulas (Y1) and (Y2), Rx1 to Rx3 each independently represent an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), an alkenyl group (linear or branched), or an aryl group (monocyclic or polycyclic). When all of Rx1 to Rx3 are alkyl groups (linear or branched), it is preferable that at least two of Rx1 to Rx3 are methyl groups. In particular, it is preferable that Rx1 to Rx3 each independently represent a linear or branched alkyl group, and it is more preferable that Rx1 to Rx3 each independently represent a linear alkyl group. Two of Rx1 to Rx3 may combine to form a monocycle or polycycle. As the alkyl groups of Rx1 to Rx3, alkyl groups having 1 to 5 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and t-butyl group are preferable. As the cycloalkyl groups of Rx1 to Rx3, monocyclic cycloalkyl groups such as cyclopentyl group and cyclohexyl group, and polycyclic cycloalkyl groups such as norbornyl group, tetracyclodecanyl group, tetracyclododecanyl group, and adamantyl group are preferable. As the aryl groups of Rx1 to Rx3, aryl groups having 6 to 10 carbon atoms are preferable, and examples thereof include phenyl group, naphthyl group, and anthryl group. As the alkenyl groups of Rx1 to Rx3, vinyl group is preferable. As the ring formed by bonding two of Rx1 to Rx3, a cycloalkyl group is preferable. As the cycloalkyl group formed by bonding two of Rx1 to Rx3, monocyclic cycloalkyl groups such as cyclopentyl group or cyclohexyl group, or polycyclic cycloalkyl groups such as norbornyl group, tetracyclodecanyl group, tetracyclododecanyl group, or adamantyl group are preferable, and monocyclic cycloalkyl groups having 5 to 6 carbon atoms are more preferable. The cycloalkyl group formed by bonding two of Rx1 to Rx3 may be, for example, one of the methylene groups constituting the ring is replaced by a hetero atom such as an oxygen atom, a group having a hetero atom such as a carbonyl group, or a vinylidene group. Further, one or more of the ethylene groups constituting the cycloalkane ring of these cycloalkyl groups may be replaced by a vinylene group. For the group represented by formula (Y1) or formula (Y2), for example, a mode in which Rx1 is a methyl group or an ethyl group, and Rx2 and Rx3 are bonded to form the above-mentioned cycloalkyl group is preferable.

[0038] In formula (Y3), R 36 ~R 38 each independently represents a hydrogen atom or a monovalent organic group. R 37 and R 38These may bond to each other to form a ring. Examples of monovalent organic groups include alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, and alkenyl groups. 36 It is also preferable that it be a hydrogen atom. Furthermore, the alkyl groups, cycloalkyl groups, aryl groups, and aralkyl groups mentioned above may include heteroatoms such as oxygen atoms and / or groups having heteroatoms such as carbonyl groups. For example, in the alkyl groups, cycloalkyl groups, aryl groups, and aralkyl groups mentioned above, one or more methylene groups may be replaced with heteroatoms such as oxygen atoms and / or groups having heteroatoms such as carbonyl groups. Also, R 38 It may bond with other substituents on the repeating main chain to form a ring. 38 The group formed by the bonding of this molecule with another substituent on the repeating main chain is preferably an alkylene group such as a methylene group.

[0039] The group represented by formula (Y3-1) below is preferred for formula (Y3).

[0040] [ka]

[0041] Here, L1 and L2 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a group combining these (for example, a group combining an alkyl group and an aryl group). M represents a single bond or a divalent linking group. Q represents an alkyl group which may contain a heteroatom, a cycloalkyl group which may contain a heteroatom, an aryl group which may contain a heteroatom, an amino group which may contain a heteroatom, an ammonium group which may contain a heteroatom, a mercapto group which may contain a cyano group which may contain an aldehyde group which may contain a heteroatom, or a group which is a combination thereof (for example, a group which is a combination of an alkyl group and a cycloalkyl group). Alkyl and cycloalkyl groups may have, for example, one of their methylene groups replaced by a heteroatom such as an oxygen atom, or a group having a heteroatom such as a carbonyl group. Preferably, one of L1 and L2 is a hydrogen atom, and the other is an alkyl group, a cycloalkyl group, an aryl group, or a group combining an alkylene group and an aryl group. At least two of Q, M, and L1 may be joined to form a ring (preferably a 5-membered or 6-membered ring). In terms of pattern refinement, L2 is preferably a secondary or tertiary alkyl group, and more preferably a tertiary alkyl group. Examples of secondary alkyl groups include isopropyl, cyclohexyl, or norbornyl groups, and examples of tertiary alkyl groups include tert-butyl or adamantane groups. In these embodiments, the Tg (glass transition temperature) and activation energy are increased, which ensures film strength and suppresses fogging.

[0042] In formula (Y4), Ar represents an aromatic ring group. Rn represents an alkyl group, a cycloalkyl group, or an aryl group. Rn and Ar may be bonded to each other to form a non-aromatic ring. Ar is more preferably an aryl group.

[0043] From the standpoint of excellent acid decomposition properties of repeating units, in the case of a leaving group that protects a polar group, if a non-aromatic ring is directly bonded to the polar group (or its residue), it is preferable that the ring member atoms in the non-aromatic ring adjacent to the ring member atom directly bonded to the polar group (or its residue) do not have halogen atoms such as fluorine atoms as substituents.

[0044] Furthermore, other preferred leaving groups that are removed by the action of acid include 2-cyclopentenyl groups having substituents (such as alkyl groups), such as 3-methyl-2-cyclopentenyl groups, and cyclohexyl groups having substituents (such as alkyl groups), such as 1,1,4,4-tetramethylcyclohexyl groups.

[0045] Furthermore, a preferred embodiment of the acid-degradable group is one in which the number of carbon atoms in the leaving group is 8 or more. When the number of carbon atoms in the leaving group of the acid-degradable group is 8 or more, the effects of the present invention tend to be more pronounced. Among the above, 8 to 20 carbon atoms are preferred, and 8 to 15 carbon atoms are more preferred.

[0046] Examples of repeating units having acid-degradable groups include the repeating unit represented by formula (AI).

[0047] [ka]

[0048] In equation (AI), Xa1 represents a hydrogen atom or an alkyl group which may have substituents. T represents a single bond or a divalent linking group. Each of Rx1 to Rx3 independently represents an alkyl group (linear or branched), a cycloalkyl group (monocyclic or polycyclic), an alkenyl group (linear or branched), or an aryl group (monocyclic or polycyclic). However, if all of Rx1 to Rx3 are alkyl groups (linear or branched), it is preferable that at least two of Rx1 to Rx3 are methyl groups. Two of Rx1 to Rx3 may bond together to form a monocyclic or polycyclic (such as a monocyclic or polycyclic cycloalkyl group).

[0049] Examples of alkyl groups that may have substituents, represented by Xa1, include a methyl group or a -CH2-R 11 The group represented by R is an example. 11 Xa1 represents a halogen atom (such as a fluorine atom), a hydroxyl group, or a monovalent organic group. Examples include alkyl groups having 5 or fewer carbon atoms that may be substituted with a halogen atom, acyl groups having 5 or fewer carbon atoms that may be substituted with a halogen atom, and alkoxy groups having 5 or fewer carbon atoms that may be substituted with a halogen atom. Alkyl groups having 3 or fewer carbon atoms are preferred, and methyl groups are more preferred. Xa1 is preferably a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0050] Examples of divalent linking groups for T include alkylene groups, aromatic ring groups, -COO-Rt- groups, and -O-Rt- groups. In the formula, Rt represents an alkylene group or a cycloalkylene group. T is preferably a single bond or a -COO-Rt- group. When T represents a -COO-Rt- group, Rt is preferably an alkylene group having 1 to 5 carbon atoms, and more preferably a -CH2- group, a -(CH2)2- group, or a -(CH2)3- group.

[0051] Preferred alkyl groups for Rx1 to Rx3 are C1 to C4 alkyl groups such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and t-butyl group. The cycloalkyl groups Rx1 to Rx3 are preferably monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl groups, or polycyclic cycloalkyl groups such as norbornyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups. The aryl groups Rx1 to Rx3 are preferably aryl groups having 6 to 10 carbon atoms, such as phenyl groups, naphthyl groups, and anthyl groups. Vinyl groups are preferred for the alkenyl groups Rx1 to Rx3. The cycloalkyl group formed by the bonding of two Rx1 to Rx3 is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, and also preferably a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. Among these, monocyclic cycloalkyl groups having 5 to 6 carbon atoms are preferred. In a cycloalkyl group formed by the bonding of two Rx1 to Rx3, for example, one of the methylene groups constituting the ring may be replaced by a heteroatom such as an oxygen atom, a group having a heteroatom such as a carbonyl group, or a vinylidene group. Furthermore, in these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced by vinylene groups. One preferred embodiment of the repeating unit represented by formula (AI) is, for example, an embodiment in which Rx1 is a methyl group or an ethyl group, and Rx2 and Rx3 are bonded together to form the cycloalkyl group described above.

[0052] When each of the above groups has substituents, examples of substituents include alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, and alkoxycarbonyl groups (2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0053] The repeating unit represented by formula (AI) is preferably an acid-degradable (meth)acrylate tertiary alkyl ester repeating unit (a repeating unit in which Xa1 represents a hydrogen atom or a methyl group, and T represents a single bond).

[0054] Furthermore, in a preferred embodiment of the repeating unit represented by formula (AI), it is preferable that the number of carbon atoms in -C(Rx1)(Rx2)(Rx3) is 8 or more, more preferably 8 to 20, and even more preferably 8 to 15.

[0055] The repeating unit having an acid-degradable group may contain only one type or two or more types. The content of repeating units having acid-degradable groups is preferably 15 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more, relative to the total repeating units in the specific acid-degradable resin. Furthermore, the upper limit is preferably 90 mol% or less, more preferably 80 mol% or less, even more preferably 70 mol% or less, and particularly preferably 60 mol% or less.

[0056] Specific examples of repeating units having acid-degradable groups are shown below, but the present invention is not limited thereto. In the formula, Xa1 is any of H, CH3, CF3, and CH2OH, and Rxa and Rxb each represent a linear or branched alkyl group having 1 to 5 carbon atoms.

[0057] [ka]

[0058] [ka]

[0059] [ka]

[0060] [ka]

[0061] [ka]

[0062] (A repeating unit containing an unsaturated bond and an acid-degradable group) As a repeating unit having an acid-degradable group containing an unsaturated bond, the repeating unit represented by formula (B) is preferred.

[0063] [ka]

[0064] In equation (B), Xb represents a hydrogen atom, a halogen atom, or an alkyl group which may have substituents. L represents a single bond or a divalent linking group which may have substituents. Each of Ry1 to Ry3 independently represents a hydrogen atom, a linear or branched alkyl group, a monocyclic or polycyclic cycloalkyl group, an alkenyl group, an alkynyl group, or a monocyclic or polycyclic aryl group. Furthermore, any two of Ry1 to Ry3 may be bonded together to form a monocyclic or polycyclic structure (for example, a monocyclic or polycyclic cycloalkyl group and a cycloalkenyl group). However, at least one of Ry1 to Ry3 represents an alkenyl group, an alkynyl group, a monocyclic or polycyclic cycloalkenyl group, or a monocyclic or polycyclic aryl group, or any two of Ry1 to Ry3 are bonded together to form a monocyclic or polycyclic alicyclic ring (for example, a monocyclic or polycyclic cycloalkyl group and a cycloalkenyl group). Furthermore, there are no cases where two or more of Ry1 to Ry3 are hydrogen atoms. If any one of Ry1 to Ry3 represents a hydrogen atom, the other two of Ry1 to Ry3 are bonded together to form a ring having one or more vinylene groups in the ring structure, and at least one of these vinylene groups is located adjacent to the carbon atom to which the hydrogen atom represented by any one of Ry1 to Ry3 is bonded.

[0065] Preferred alkyl groups for Ry1 to Ry3 are C1 to C4 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups. The cycloalkyl groups Ry1 to Ry3 are preferably monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl groups, or polycyclic cycloalkyl groups such as norbornyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups. The aryl groups Ry1 to Ry3 are preferably aryl groups having 6 to 15 carbon atoms, and more preferably aryl groups having 6 to 10 carbon atoms, such as phenyl groups, naphthyl groups, and anthryl groups. A vinyl group is preferred as the alkenyl group for Ry1 to Ry3. An ethynyl group is preferred as the alkynyl group for Ry1 to Ry3. The cycloalkenyl groups of Ry1 to Ry3 are preferably cyclopentyl groups and monocyclic cycloalkyl groups that include a double bond in part. The cycloalkyl group formed by the bonding of two Ry1-Ry3 groups is preferably a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, and also preferably a polycyclic cycloalkyl group such as a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, or an adamantyl group. Among these, monocyclic cycloalkyl groups having 5-6 carbon atoms are preferred. The cycloalkyl and cycloalkenyl groups formed by the bonding of two Ry1 to Ry3 may have, for example, one of the methylene groups constituting the ring replaced by a heteroatom such as an oxygen atom, a carbonyl group, a group having a heteroatom such as a -SO2- group or a -SO3- group, a vinylidene group, or a combination thereof. Furthermore, one or more of the ethylene groups constituting the cycloalkane and cycloalkene rings of these cycloalkyl and cycloalkenyl groups may be replaced by vinylene groups. One preferred embodiment of the Ry1-Ry3 combination is, for example, a configuration in which Ry1 is a methyl group, an ethyl group, a vinyl group, an allyl group, or an aryl group, and Ry2 and Ry3 are bonded together to form the aforementioned cycloalkyl group or cycloalkenyl group; and a configuration in which Ry1 is a hydrogen atom, and Ry2 and Ry3 are bonded together to form a ring having one or more vinylene groups in the ring structure, and at least one of these vinylene groups is adjacent to the carbon atom to which the hydrogen atom represented by Ry1 is bonded.

[0066] If Ry1 to Ry3 have further substituents, examples of substituents include alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, and alkoxycarbonyl groups (2 to 6 carbon atoms). The number of carbon atoms in the substituents is preferably 8 or less.

[0067] Examples of alkyl groups that may have substituents, represented by Xb, include a methyl group or a -CH2-R 11 The group represented by R is an example. 11Xb represents a halogen atom (such as a fluorine atom), a hydroxyl group, or a monovalent organic group. Examples include alkyl groups having 5 or fewer carbon atoms that may be substituted with a halogen atom, acyl groups having 5 or fewer carbon atoms that may be substituted with a halogen atom, and alkoxy groups having 5 or fewer carbon atoms that may be substituted with a halogen atom. Alkyl groups having 3 or fewer carbon atoms are preferred, and methyl groups are more preferred. Xb is preferably a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0068] Examples of divalent linking groups for L include -Rt-, -CO-, -COO-Rt-, -COO-Rt-CO-, -Rt-CO-, and -O-Rt-. In the formula, Rt represents an alkylene group, a cycloalkylene group, or an aromatic ring group, with an aromatic ring group being preferred. L is preferably a -Rt- group, a -CO- group, a -COO-Rt-CO- group, or a -Rt-CO- group. Rt may have substituents such as a halogen atom, a hydroxyl group, or an alkoxy group. An aromatic group is preferred.

[0069] Furthermore, if each of the above groups in formula (B) has substituents, examples of substituents include alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, and alkoxycarbonyl groups (2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0070] The repeating units represented by formula (B) are preferably acid-degradable (meth)acrylic acid tertiary ester repeating units (where Xb represents a hydrogen atom or a methyl group and L represents a -CO- group), acid-degradable hydroxystyrene tertiary alkyl ether repeating units (where Xb represents a hydrogen atom or a methyl group and L represents a phenyl group), or acid-degradable styrene carboxylic acid tertiary ester repeating units (where Xb represents a hydrogen atom or a methyl group and L represents a -Rt-CO- group (where Rt is an aromatic group)).

[0071] Furthermore, one preferred embodiment of the repeating unit represented by formula (B) is one in which the number of carbon atoms in the leaving group contained in the acid-degradable group contained in formula (B) is 8 or more. The number of carbon atoms in the leaving group contained in the acid-degradable group is more preferably 8 to 20, and even more preferably 8 to 15. Furthermore, in a preferred embodiment of the repeating unit represented by formula (B), the total number of carbon atoms in the group represented by -C(Ry1)(Ry2)(Ry3) is preferably 8 or more, more preferably 8 to 20, and even more preferably 8 to 15.

[0072] The repeating unit having an acid-degradable group containing an unsaturated bond may be present in a single form or in a set of two or more forms. The content of repeating units having acid-degradable groups containing unsaturated bonds is preferably 15 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more, relative to the total repeating units in the specific acid-degradable resin. Furthermore, the upper limit is preferably 80 mol% or less, more preferably 70 mol% or less, and particularly preferably 60 mol% or less.

[0073] Specific examples of repeating units having acid-degradable groups containing unsaturated bonds are shown below, but the present invention is not limited thereto. In the formula, Xb and L1 represent any of the substituents or linking groups described above, Ar represents an aromatic group, R represents a substituent such as a hydrogen atom, alkyl group, cycloalkyl group, aryl group, aralkyl group, alkenyl group, hydroxyl group, alkoxy group, acyloxy group, cyano group, nitro group, amino group, halogen atom, ester group (-OCOR''' or -COOR''':R''' is an alkyl group or fluorinated alkyl group having 1 to 20 carbon atoms), or carboxyl group, R' represents a linear or branched alkyl group, monocyclic or polycyclic cycloalkyl group, alkenyl group, alkynyl group, monocyclic or polycyclic aryl group, Q represents a heteroatom such as an oxygen atom, a carbonyl group, a group having a heteroatom such as a -SO2- group or -SO3- group, or a vinylidene group, or a combination thereof. l, n, and m represent integers of 0 or more. There is no upper limit; for example, it can be 6 or less, and preferably 4 or less.

[0074] [ka]

[0075] [ka]

[0076] [ka]

[0077] [ka]

[0078] The specific acid-degradable resin may contain repeating units other than those described above. For example, the specific acid-degradable resin preferably contains at least one repeating unit selected from the group consisting of (X1) to (X4) below. (X1) Repeating unit having an acid group, as described later (X2) Repeating unit having at least one group selected from lactone groups, sultone groups, and carbonate groups, as described later. (X3) A repeating unit having at least one group selected from an alcoholic hydroxyl group and a cyano group, as described later. (X4) Repeating unit represented by formula (III), which will be described later.

[0079] As a specific acid-degradable resin, it is also preferable that it does not contain either fluorine or silicon atoms, as this further improves its suitability for ArF immersion lithography. Furthermore, as a specific acid-degradable resin, it is also preferable that it does not have aromatic groups, as this further improves its suitability for ArF immersion lithography.

[0080] Furthermore, in the repeating units in the specific acid-degradable resins listed below, for example, the repeating units having an acid group, the repeating units having an alcoholic hydroxyl group in the <repeating units having at least one group selected from an alcoholic hydroxyl group and a cyano group>, etc., are considered repeating units having a hydrophilic group. Furthermore, in the repeating units shown, for example, in the <repeating units having an acid-degradable group>, <repeating units having a lactone group, a sultone group, or a carbonate group>, and the repeating units having a cyano group in the <repeating units having at least one group selected from an alcoholic hydroxyl group and a cyano group>, repeating units having a hydrophilic group as a substituent are also considered repeating units having a hydrophilic group.

[0081] <Repeating unit with acidic group> The specific acid-degradable resin preferably contains repeating units having acid groups. As for the acid group, an acid group with a pKa of 13 or less is preferred. The acid dissociation constant of the above acid group is preferably 13 or less, more preferably 3 to 13, and even more preferably 5 to 10. When a specific acid-degradable resin has acid groups with a pKa of 13 or less, the content of acid groups in the specific acid-degradable resin is not particularly limited, but is often between 0.2 and 6.0 mmol / g. Among these, 0.8 to 6.0 mmol / g is preferred, 1.2 to 5.0 mmol / g is more preferred, and 1.6 to 4.0 mmol / g is even more preferred. If the acid group content is within the above range, development proceeds well, the resulting pattern shape is excellent, and the resolution is also excellent. Preferred acidic groups include, for example, carboxyl groups, phenolic hydroxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol groups), sulfonic acid groups, sulfonamide groups, or isopropanol groups. In addition, one or more (preferably 1 to 2) of the fluorine atoms in the hexafluoroisopropanol group may be substituted with a group other than a fluorine atom (such as an alkoxycarbonyl group). The thus-formed -C(CF3)(OH)-CF2- is also preferable as an acid group. Further, one or more of the fluorine atoms may be substituted with a group other than a fluorine atom to form a ring containing -C(CF3)(OH)-CF2-. The repeating unit having an acid group is preferably a repeating unit having the above-mentioned acid-decomposable group, a repeating unit having a lactone group, a sultone group, or a carbonate group described later, a repeating unit having at least one kind of group selected from the alcoholic hydroxyl group and the cyano group described later, and a repeating unit different from the repeating unit represented by the formula (III) described later.

[0082] The repeating unit having an acid group may have a fluorine atom or an iodine atom.

[0083] Examples of the repeating unit having an acid group include a repeating unit represented by the formula (B).

[0084] [Chemical formula]

[0085] R3 represents a hydrogen atom or a monovalent organic group. As the monovalent organic group, a group represented by -L4-R8 is preferable. L4 represents a single bond or an ester group. R8 includes an alkyl group, a cycloalkyl group which may have a fluorine atom or an iodine atom, an aryl group, or a group combining these.

[0086] R4 and R5 each independently represent a hydrogen atom, a fluorine atom, an iodine atom, or an alkyl group which may have a fluorine atom or an iodine atom.

[0087] L2 represents a divalent group formed by a combination of a single bond, an ester group, or -CO-, -O-, and an alkylene group (preferably having 1 to 6 carbon atoms; it may be linear or branched; and -CH2- may be substituted with a halogen atom). L3 represents an (n+m+1) valent aromatic hydrocarbon ring group or an (n+m+1) valent alicyclic hydrocarbon ring group. Examples of aromatic hydrocarbon ring groups include benzene ring groups and naphthalene ring groups. Alicyclic hydrocarbon ring groups may be monocyclic or polycyclic, and examples include cycloalkyl ring groups, norbornene ring groups, and adamantane ring groups. L3 preferably represents an alicyclic hydrocarbon ring group with an (n+m+1) valency.

[0088] R6 represents a hydroxyl group or a fluorinated alcohol group. The fluorinated alcohol group is preferably a monovalent group represented by the following formula (3L). *-L 6X -R 6X (3L) L 6X - represents a single bond or a divalent linking group. There are no particular restrictions on the divalent linking group, but examples include -CO-, -O-, -SO-, -SO2-, and -NR. A - Examples include alkylene groups (preferably having 1 to 6 carbon atoms; may be linear or branched), and divalent linking groups formed by combining multiple thereof. A Examples of substituents include hydrogen atoms or alkyl groups having 1 to 6 carbon atoms. Furthermore, the alkylene group may have substituents. Examples of substituents include halogen atoms (preferably fluorine atoms) and hydroxyl groups. 6X This represents a hexafluoroisopropanol group. Furthermore, if R6 is a hydroxyl group, it is also preferable that L3 is an (n+m+1) valent aromatic hydrocarbon ring group. R7 represents a halogen atom. Examples of halogen atoms include fluorine, chlorine, bromine, or iodine. m represents an integer greater than or equal to 1. m is preferably an integer between 1 and 3, and preferably between 1 and 2. n represents an integer of 0 or greater than or equal to 1. Preferably, n is an integer between 1 and 4. (n+m+1) is preferably an integer between 1 and 5.

[0089] Examples of repeating units having an acidic group include the following:

[0090] [ka]

[0091] [ka]

[0092] [ka]

[0093] The repeating units containing acidic groups may consist of only one type or two or more types. The content of repeating units having acid groups is preferably 1 mol% or more, and more preferably 5 mol% or more, relative to the total repeating units in the specific acid-degradable resin. Furthermore, the upper limit is preferably 50 mol% or less, more preferably 40 mol% or less, and even more preferably 30 mol% or less.

[0094] <Repeating units having a lactone group, sultone group, or carbonate group> The specific acid-degradable resin may have repeating units having at least one selected from the group consisting of lactone groups, sultone groups, and carbonate groups (hereinafter collectively referred to as "repeating units having lactone groups, sultone groups, or carbonate groups"). It is also preferable that the repeating units having a lactone group, a sultone group, or a carbonate group do not have acidic groups such as a hydroxyl group or a hexafluoropropanol group.

[0095] As the lactone group or sultone group, it only needs to have a lactone structure or a sultone structure. The lactone structure or sultone structure is preferably a 5- to 7-membered lactone structure or a 5- to 7-membered sultone structure. Among them, those in which another ring structure is fused to the 5- to 7-membered lactone structure in the form of forming a bicyclic structure or a spiro structure, or those in which another ring structure is fused to the 5- to 7-membered sultone structure in the form of forming a bicyclic structure or a spiro structure, are more preferable. The specific acid-decomposable resin preferably contains a repeating unit having a lactone group or a sultone group formed by extracting one or more hydrogen atoms from the ring member atoms of a lactone structure represented by any of the following formulas (LC1-1) to (LC1-21) or a sultone structure represented by any of the following formulas (SL1-1) to (SL1-3). Also, the lactone group or sultone group may be directly bonded to the main chain. For example, the ring member atoms of the lactone group or sultone group may constitute the main chain of the specific acid-decomposable resin.

[0096]

Chemical formula

[0097] The above lactone structure or sultone structure portion may have a substituent (Rb2). Preferred substituents (Rb2) 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 1 to 8 carbon atoms, a carboxy group, a halogen atom, a cyano group, and an acid-decomposable group, etc. n2 represents an integer of 0 to 4. When n2 is 2 or more, the plurality of Rb2 may be different, and the plurality of Rb2 may be bonded to each other to form a ring.

[0098] Examples of the repeating unit having a group having a lactone structure represented by any of the formulas (LC1-1) to (LC1-21) or a sultone structure represented by any of the formulas (SL1-1) to (SL1-3) include a repeating unit represented by the following formula (AI), etc.

[0099] [ka]

[0100] In formula (AI), Rb0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. Preferred substituents that the alkyl group of Rb0 may have include a hydroxyl group and a halogen atom. Examples of halogen atoms for Rb0 include fluorine, chlorine, bromine, and iodine. Rb0 is preferably a hydrogen atom or a methyl group. Ab represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, a carboxyl group, or a divalent group combining these. Among these, a single bond or a linking group represented by -Ab1-CO2- is preferred. Ab1 is a linear or branched alkylene group, or a monocyclic or polycyclic cycloalkylene group, and a methylene group, ethylene group, cyclohexylene group, adamantylene group, or norbornylene group is preferred. V represents a group obtained by removing one hydrogen atom from a ring member atom of a lactone structure represented by any of the formulas (LC1-1) to (LC1-21), or a group obtained by removing one hydrogen atom from a ring member atom of a sultone structure represented by any of the formulas (SL1-1) to (SL1-3).

[0101] If optical isomers exist for a repeating unit having a lactone group or a sultone group, either optical isomer may be used. Furthermore, one optical isomer may be used alone, or multiple optical isomers may be used in mixture form. When primarily using one optical isomer, its optical purity (ee) is preferably 90 or higher, and more preferably 95 or higher.

[0102] A cyclic carbonate ester group is preferred as the carbonate group. As a repeating unit having a cyclic carbonate ester group, the repeating unit represented by the following formula (A-1) is preferred.

[0103] [ka]

[0104] In formula (A-1), R A 1 This represents a hydrogen atom, a halogen atom, or a monovalent organic group (preferably a methyl group). n represents a non-negative integer. R A 2 represents a substituent. If n is 2 or greater, there are multiple R A 2 These may be the same or different. A represents a single bond or a divalent linking group. Preferred divalent linking groups include alkylene groups, divalent linking groups having a monocyclic or polycyclic alicyclic hydrocarbon structure, ether groups, ester groups, carbonyl groups, carboxyl groups, or divalent groups that are combinations thereof. Z represents an atomic group that forms a monocyclic or polycyclic ring with the group represented by -O-CO-O- in the formula. The number of ring member atoms in the ring formed by the group represented by -O-CO-O- and the atomic group represented by Z is not particularly limited, for example, 5 to 10 is preferred, 5 to 8 is more preferred, and 5 is even more preferred.

[0105] Examples of repeating units having a lactone group, a sultone group, or a carbonate group are shown below.

[0106] [ka]

[0107] [ka]

[0108] [ka]

[0109] The repeating unit having a lactone group, a sultone group, or a carbonate group may contain only one type or two or more types. The content of repeating units having lactone groups, sultone groups, or carbonate groups is preferably 1 mol% or more, and more preferably 10 mol% or more, relative to the total repeating units in the specific acid-degradable resin. Furthermore, the upper limit is preferably 85 mol% or less, more preferably 80 mol% or less, even more preferably 70 mol% or less, and particularly preferably 60 mol% or less.

[0110] The specific acid-degradable resin preferably contains repeating units having at least one group selected from alcoholic hydroxyl groups and cyano groups. This improves substrate adhesion and developer affinity. The repeating unit having an alcoholic hydroxyl group or a cyano group is more preferably a repeating unit having an alicyclic hydrocarbon structure substituted with an alcoholic hydroxyl group or a cyano group. It is preferable that the repeating units having an alcoholic hydroxyl group or a cyano group do not have an acid-degradable group. Examples of repeating units having an alcoholic hydroxyl group or a cyano group include the repeating units represented by the following formulas (AIIa) to (AIId).

[0111] [ka]

[0112] In the formula (AIIa)~(AIId), R1c represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group. Each of R2c to R4c independently represents a hydrogen atom, a hydroxyl group (alcoholic hydroxyl group), or a cyano group. However, at least one of R2c to R4c represents a hydroxyl group or a cyano group. Preferably, one or two of R2c to R4c represent hydroxyl groups and the rest are hydrogen atoms. Among the repeating units having an alcoholic hydroxyl group or a cyano group, it is preferable that the repeating unit is represented by formula (AIIa), and more preferably that two of R2c to R4c represent hydroxyl groups and the remaining one represents a hydrogen atom.

[0113] Specific examples of repeating units having a hydroxyl group or a cyano group are listed below, but the present invention is not limited to these.

[0114] [ka]

[0115] Furthermore, another preferred embodiment of a repeating unit having an alcoholic hydroxyl group is a repeating unit having a linear or branched alkyl group substituted with an alcoholic hydroxyl group. Examples of such repeating units having an alcoholic hydroxyl group include alkyl (meth)acrylates in which the alkyl moiety is an alkyl group having 1 to 10 carbon atoms substituted with one or more hydroxyl groups.

[0116] The repeating unit having an alcoholic hydroxyl group or a cyano group may be present in a single form or in a set of two or more forms. The content of repeating units having alcoholic hydroxyl groups or cyano groups is preferably 1 mol% or more, and more preferably 5 mol% or more, relative to the total repeating units in the specific acid-degradable resin. Furthermore, the upper limit is preferably 40 mol% or less, more preferably 30 mol% or less, and even more preferably 25 mol% or less.

[0117] <Repeating unit represented by formula (III)> The specific acid-degradable resin may contain repeating units represented by formula (III).

[0118] [ka]

[0119] In formula (III), R5 represents a hydrocarbon group having a cyclic structure and lacking polar groups. Ra represents a hydrogen atom, an alkyl group, or a -CH2-O-Ra2 group. In the formula, Ra2 represents a hydrogen atom, an alkyl group, or an acyl group. The Ra is preferably a hydrogen atom, a methyl group, a hydroxymethyl group, or a trifluoromethyl group, with a hydrogen atom or a methyl group being more preferred. The cyclic structure of R5 may be either monocyclic or polycyclic. In other words, R5 may be either a monocyclic hydrocarbon group or a polycyclic hydrocarbon group. Examples of monocyclic hydrocarbon groups include cycloalkyl groups having 3 to 12 carbon atoms, such as cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups, and cycloalkenyl groups having 3 to 12 carbon atoms, such as cyclohexenyl groups. Monocyclic hydrocarbon groups having 3 to 7 carbon atoms are preferred, and cyclopentyl or cyclohexyl groups are even more preferred.

[0120] Examples of polycyclic hydrocarbon groups include ring-aggregated hydrocarbon groups and bridged cyclic hydrocarbon groups. Examples of ring-assembled hydrocarbon groups include bicyclohexyl groups and perhydronaphthalenyl groups. Examples of bridging cyclic hydrocarbon rings include bicyclic hydrocarbon rings such as pinane, bornane, norpinane, norbornane, and bicyclooctane rings (bicyclo[2.2.2]octane rings and bicyclo[3.2.1]octane rings, etc.); homobredan, adamantane, tricyclo[5.2.1.0 2,6 ] Decane, and tricyclo[4.3.1.1 2,5 ]Tricyclic hydrocarbon rings such as undecane rings; tetracyclo[4.4.0.1 2,5 .1 7,10Examples include dodecane and tetracyclic hydrocarbon rings such as perhydro-1,4-methano-5,8-methanonaphthalene rings; and condensed rings in which multiple 5- to 8-membered cycloalkane rings are fused together, such as perhydronaphthalene (decalin), perhydroanthracene, perhydrophenanthrene, perhydroacenaphthene, perhydrofluorene, perhydroindene, and perhydrophenalene rings.

[0121] Examples of polycyclic hydrocarbon groups include norbornyl, adamantyl, bicyclooctanyl, or tricyclo[5,2,1,0] 2,6 A decanyl group is preferred, and a norbonyl group or an adamantyl group is more preferred.

[0122] The cyclic structure of R5 may further have substituents. Examples of substituents include halogen atoms, alkyl groups, cycloalkyl groups, aralkyl groups, alkoxy groups, amino groups, alkoxycarbonyl groups, and aralkyloxycarbonyl groups.

[0123] The following are specific examples of the repeating unit represented by formula (III). In the formula, Ra represents H, CH3, CH2OH, or CF3.

[0124] [ka]

[0125] The repeating unit represented by formula (III) may contain only one type or two or more types. The content of the repeating units represented by formula (III) is preferably 1 mol% or more, and more preferably 5 mol% or more, relative to the total repeating units in the specific acid-degradable resin. Furthermore, the upper limit is preferably 40 mol% or less, more preferably 30 mol% or less, and even more preferably 25 mol% or less.

[0126] In addition to the repeating structural units described above, the specific acid-degradable resin may have various repeating structural units for the purpose of adjusting dry etching resistance, suitability for standard developers, substrate adhesion, resist profile, resolution, heat resistance, and sensitivity.

[0127] As a specific acid-degradable resin, it is also preferable that all repeating units are composed of (meth)acrylate repeating units. In this case, any of the following can be used: all repeating units are methacrylate repeating units, all repeating units are acrylate repeating units, or all repeating units are composed of methacrylate repeating units and acrylate repeating units, and it is preferable that the acrylate repeating units make up 50 mol% or less of the total repeating units.

[0128] Specific acid-degradable resins can be synthesized according to conventional methods (e.g., radical polymerization).

[0129] In the resist composition, the content of the specific acid-degradable resin is preferably 50.0 to 99.9% by mass, more preferably 60.0 to 99.0% by mass, and even more preferably 70.0 to 99.0% by mass, based on the total solid content of the composition. Furthermore, specific acid-degradable resins may be used individually or in combination of multiple types.

[0130] <<(B) Component (Photoacid Generator)>> The resist composition contains a photoacid generator. A photoacid generator is a compound that generates acid upon irradiation with active light or radiation. Preferred photoacid generators are compounds that generate organic acids upon irradiation with active light or radiation. Examples include sulfonium salt compounds, iodonium salt compounds, diazonium salt compounds, phosphonium salt compounds, imidosulfonate compounds, oximesulfonate compounds, diazodisulfone compounds, disulfone compounds, and o-nitrobenzylsulfonate compounds.

[0131] As photoacid generators, known compounds that generate acid upon irradiation with active light or radiation can be appropriately selected and used individually or in mixtures thereof. For example, known compounds disclosed in paragraphs

[0125] to

[0319] of U.S. Patent Application Publication 2016 / 0070167A1, paragraphs

[0086] to

[0094] of U.S. Patent Application Publication 2015 / 0004544A1, and paragraphs

[0323] to

[0402] of U.S. Patent Application Publication 2016 / 0237190A1 can be suitably used as photoacid generators.

[0132] As a photoacid generator, for example, compounds represented by the following formulas (ZI), (ZII), or (ZIII) are preferred.

[0133] [ka]

[0134] In the above equation (ZI), R 201 , R 202 and R 203 Each of these independently represents an organic group. R 201 , R 202 and R 203 The number of carbon atoms in the organic group is generally 1 to 30, with 1 to 20 being preferred. Also, R 201 ~R 203 Two of these may bond together 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. 201 ~R 203 Examples of groups formed by the bonding of two of these include alkylene groups (e.g., butylene groups and pentylene groups) and -CH2-CH2-O-CH2-CH2-. Z - This represents an anion.

[0135] Preferred embodiments of the cation in formula (ZI) include the corresponding groups in compounds (ZI-1), (ZI-2), (ZI-3), and (ZI-4), which will be described later. The photoacid generator may be a compound having multiple structures represented by formula (ZI). For example, the R of a compound represented by formula (ZI) 201 ~R 203 At least one of the and R of another compound represented by formula (ZI) 201 ~R 203 The compound may have a structure in which at least one of the compounds is bonded via a single bond or a linking group.

[0136] First, let me explain compound (ZI-1). Compound (ZI-1) is R of the above formula (ZI) 201 ~R 203 An arylsulfonium compound is a compound in which at least one of the groups is an aryl group, i.e., a compound with an arylsulfonium cation. Aryl sulfonium compounds are R 201 ~R 203 All of them may be aryl groups, or R 201 ~R 203 A portion of the group may be an aryl group, and the remainder may be an alkyl group or a cycloalkyl group. Examples of arylsulfonium compounds include triarylsulfonium compounds, diarylalkylsulfonium compounds, aryldialkylsulfonium compounds, diarylcycloalkylsulfonium compounds, and aryldicycloalkylsulfonium compounds.

[0137] The aryl group in the arylsulfonium compound is preferably a phenyl group or a naphthyl group, with the phenyl group being more preferred. The aryl group may be an aryl group having a heterocyclic structure containing an oxygen atom, a nitrogen atom, or a sulfur atom. Examples of heterocyclic structures include pyrrole residues, furan residues, thiophene residues, indole residues, benzofuran residues, and benzothiophene residues. When the arylsulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different. The alkyl or cycloalkyl group that the arylsulfonium compound may optionally contain is preferably a linear alkyl group having 1 to 15 carbon atoms, a branched alkyl group having 3 to 15 carbon atoms, or a cycloalkyl group having 3 to 15 carbon atoms. Examples include methyl, ethyl, propyl, n-butyl, sec-butyl, t-butyl, cyclopropyl, cyclobutyl, and cyclohexyl groups.

[0138] R 201 ~R 203 The aryl group, alkyl group, and cycloalkyl group represented by may each independently have alkyl groups (e.g., having 1 to 15 carbon atoms), cycloalkyl groups (e.g., having 3 to 15 carbon atoms), aryl groups (e.g., having 6 to 14 carbon atoms), alkoxy groups (e.g., having 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, or phenylthio groups as substituents.

[0139] Next, we will explain compound (ZI-2). Compound (ZI-2) is R in formula (ZI). 201 ~R 203 However, each of these compounds independently represents an organic group that does not contain an aromatic ring. Here, the term "aromatic ring" also includes aromatic rings containing heteroatoms. R 201 ~R 203 Organic groups that do not have an aromatic ring generally have 1 to 30 carbon atoms, with 1 to 20 carbon atoms being preferred. R 201 ~R 203Each of these is preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, more preferably a linear or branched 2-oxoalkyl group, a 2-oxocycloalkyl group, or an alkoxycarbonylmethyl group, and even more preferably a linear or branched 2-oxoalkyl group.

[0140] R 201 ~R 203 Preferably, the alkyl and cycloalkyl groups are linear alkyl groups having 1 to 10 carbon atoms or branched alkyl groups having 3 to 10 carbon atoms (e.g., methyl group, ethyl group, propyl group, butyl group, and pentyl group), or cycloalkyl groups having 3 to 10 carbon atoms (e.g., cyclopentyl group, cyclohexyl group, and norbornyl group). R 201 ~R 203 This may be further substituted with a halogen atom, an alkoxy group (e.g., having 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

[0141] Next, we will explain compound (ZI-3). Compound (ZI-3) is a compound represented by the following formula (ZI-3).

[0142] [ka]

[0143] In the above formula (ZI-3), R1 represents an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, or an alkenyl group. The alkyl group represented by R1 (which may be linear or branched) has 1 to 10 carbon atoms, and more preferably 1 to 6 carbon atoms. The cycloalkyl group represented by R1 preferably has 3 to 10 carbon atoms. Examples of cycloalkyl groups include cyclopentyl, cyclohexyl, and norbornyl groups. The alkoxy group represented by R1 (the alkyl group portion may be linear or branched) has 1 to 10 carbon atoms, and more preferably 1 to 6 carbon atoms. The number of carbon atoms in the cycloalkoxy group represented by R1 is preferably 3 to 10, and more preferably 3 to 6. The aryl group represented by R1 is preferably an aryl group having 6 to 18 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. Examples include a phenyl group, a naphthyl group, and an anthyl group. A vinyl group is preferred as the alkenyl group represented by R1.

[0144] The alkyl group, cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, and alkenyl group represented by R1 above may have further substituents. Examples of substituents include alkyl groups, cycloalkyl groups, aryl groups, alkoxy groups, aryloxy groups, alkoxycarbonyl groups, alkylcarbonyloxy groups, cycloalkylcarbonyloxy groups, halogen atoms, hydroxyl groups, nitro groups, alkylthio groups, and arylthio groups. The number of carbon atoms in the alkyl portion (which may be linear or branched) of an alkyl group, alkoxy group, alkoxycarbonyl group, alkylcarbonyloxy group, and alkylthio group is preferably 1 to 10, and more preferably 1 to 6. The number of carbon atoms in the alkyl portion of the cycloalkyl group and cycloalkylcarbonyloxy group is preferably 3 to 20, more preferably 5 to 10, and even more preferably 6 to 10. The aryl group in the aryl group, aryloxy group, and arylthio group is preferably an aryl group having 6 to 10 carbon atoms, such as a phenyl group, naphthyl group, and anthyl group.

[0145] R2 and R3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, or an aryl group. Specific examples of alkyl groups, cycloalkyl groups, alkoxy groups, cycloalkoxy groups, and aryl groups represented by R2 and R3 are the same as the specific examples shown above for alkyl groups, cycloalkyl groups, alkoxy groups, cycloalkoxy groups, and aryl groups represented by R1. Note that R1 and R2 may be bonded to each other to form a ring. Also, R2 and R3 may be bonded to each other to form a ring. The rings formed by the bonding of R1 and R2, and R2 and R3, may be either aromatic rings or alicyclic rings. The number of ring members is, for example, 3 to 10, preferably 4 to 8, and more preferably 5 or 6.

[0146] Also, R X and R y Each of these independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, or an alkoxycarbonylcycloalkyl group. R X and R y Specific examples of alkyl groups, cycloalkyl groups, alkenyl groups, and aryl groups represented by R1 are the same as those shown above for alkyl groups, cycloalkyl groups, alkenyl groups, and aryl groups represented by R1. R X and R y The number of carbon atoms in the 2-oxoalkyl group (which may be linear or branched) represented by is preferably 1 to 10, and more preferably 1 to 6. R X and R y The number of carbon atoms in the alkoxycarbonylalkyl group represented by (which may be linear or branched) is preferably 2 to 12, more preferably 2 to 10, and even more preferably 2 to 6. R X and R y The number of carbon atoms in the 2-oxocycloalkyl group represented by is preferably 3 to 20, more preferably 5 to 10, and even more preferably 6 to 10. R X and Ry The number of carbon atoms in the alkoxycarbonylcycloalkyl group represented by (the alkoxy portion may be linear or branched) is preferably 5 to 20, more preferably 5 to 10, and even more preferably 6 to 10.

[0147] Note, R X and R y They may be bonded to each other to form a ring. X and R y The ring formed by the bonding of these elements may be either an aromatic ring or an alicyclic ring. The number of ring members is, for example, 3 to 10, preferably 4 to 8, and more preferably 5 or 6. The ring may also contain oxygen atoms, nitrogen atoms, sulfur atoms, ketone groups, ether bonds, ester bonds, or amide bonds.

[0148] Z - This represents an anion.

[0149] Next, we will explain compound (ZI-4). Compound (ZI-4) is represented by the following formula (ZI-4).

[0150] [ka]

[0151] In formula (ZI-4), l represents an integer between 0 and 2, preferably 0 or 1. r represents an integer between 0 and 8, preferably between 0 and 4. R a1 represents a hydrogen atom, a fluorine atom, a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, or an alkoxycarbonyl group. These groups may have substituents. R a1 Specific examples of alkyl groups, cycloalkyl groups, and alkoxy groups represented by the above formula (ZI-3) include those similar to the specific examples shown for the alkyl group, cycloalkyl group, and alkoxy group represented by R1 in the above formula (ZI-3). R a1The number of carbon atoms of the alkoxycarbonyl group represented by (which may be linear or branched) is preferably 2 to 10, more preferably 2 to 6.

[0152] R b1 each independently represents an alkyl group, a cycloalkyl group, or a naphthyl group. These groups may have substituents. R a1 Specific examples of the alkyl group and cycloalkyl group represented by are the same as those exemplified for the alkyl group and cycloalkyl group represented by R1 in the above formula (ZI-3). Also, when R b1 has a substituent, examples of the substituent are the same as those exemplified as the substituent such as the alkyl group of R1 in the above formula (ZI-3). Incidentally, two R b1 may be bonded to each other to form a ring. When two R b1 are bonded to each other to form a ring, this ring may contain an oxygen atom, a nitrogen atom, a sulfur atom, a ketone group, an ether bond, an ester bond, or an amide bond. R b1 As a preferred embodiment of, there is an embodiment in which two R b1 are alkylene groups and are bonded to each other to form a ring structure (alicyclic structure). The above ring structure is preferably a 5- to 6-membered ring, more preferably a 5-membered ring.

[0153] R c1 represents a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, or a cycloalkylsulfonyl group. These groups may have substituents. Incidentally, when r is an integer of 2 or more, a plurality of R c1 may be the same as or different from each other.

[0154] X - represents an anion.

[0155] Next, the formulas (ZII) and (ZIII) will be described. In the formulas (ZII) and (ZIII), R 204 ~R 207 each independently represents an aryl group, an alkyl group, or a cycloalkyl group. R 204 ~R 207 The aryl group represented by is preferably a phenyl group or a naphthyl group, more preferably a phenyl group. R 204 ~R 207 The aryl group represented by may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom, etc. Examples of the skeleton of the aryl group having a heterocyclic structure include pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene. R 204 ~R 207 The alkyl group and cycloalkyl group represented by are preferably a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, butyl group, and pentyl group, etc.), or a cycloalkyl group having 3 to 10 carbon atoms (for example, cyclopentyl group, cyclohexyl group, and norbornyl group, etc.).

[0156] R 204 ~R 207 The aryl group, alkyl group, and cycloalkyl group represented by may each independently have a substituent. R 204 ~R 207 Examples of the substituent that the aryl group, alkyl group, and cycloalkyl group represented by may have include an alkyl group (for example, having 1 to 15 carbon atoms), a cycloalkyl group (for example, having 3 to 15 carbon atoms), an aryl group (for example, having 6 to 15 carbon atoms), an alkoxy group (for example, having 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, and a phenylthio group, etc. Z - represents an anion.

[0157] Z in the formula (ZI) - , Z in the formula (ZII) - , Z in the formula (ZI-3)- , and X in equation (ZI-4) - The anion represented by the following formula (3) is preferred.

[0158] [ka]

[0159] In formula (3), o represents an integer from 1 to 3. p represents an integer from 0 to 10. q represents an integer from 0 to 10.

[0160] Xf represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. The number of carbon atoms in this alkyl group is preferably 1 to 10, and more preferably 1 to 4. Furthermore, perfluoroalkyl groups are preferred as the alkyl group substituted with at least one fluorine atom. Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms, and more preferably a fluorine atom or CF3. In particular, it is even more preferable that both Xf are fluorine atoms.

[0161] R4 and R5 each independently represent a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom. If there are multiple R4 and R5, they may be the same or different. The alkyl groups represented by R4 and R5 may have substituents, and preferably have 1 to 4 carbon atoms. R4 and R5 are preferably hydrogen atoms. Specific examples and preferred embodiments of alkyl groups substituted with at least one fluorine atom are the same as the specific examples and preferred embodiments of Xf in formula (3).

[0162] L represents a divalent linking group. If there are multiple Ls, they may be the same or different. Examples of divalent linking groups include -COO-, -CONH-, -CO-, -O-, -S-, -SO-, -SO2-, alkylene groups (preferably with 1 to 6 carbon atoms), cycloalkylene groups (preferably with 3 to 15 carbon atoms), alkenylene groups (preferably with 2 to 6 carbon atoms), and divalent linking groups formed by combining multiple thereof. Among these, -COO-, -CONH-, -CO-, -O-, -SO2-, -COO-alkylene group-, -OCO-alkylene group-, -CONH-alkylene group-, or -NHCO-alkylene group- are preferred, and -COO-, -CONH-, -SO2-, -COO-alkylene group-, or -OCO-alkylene group- are more preferred.

[0163] W represents an organic group containing a cyclic structure. Among these, a cyclic organic group is preferred. Examples of cyclic organic groups include alicyclic groups, aryl groups, and heterocyclic groups. The alicyclic group may be monocyclic or polycyclic. Examples of monocyclic alicyclic groups include monocyclic cycloalkyl groups such as cyclopentyl, cyclohexyl, and cyclooctyl groups. Examples of polycyclic alicyclic groups include polycyclic cycloalkyl groups such as norbornyl, tricyclodecanyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups. Among these, alicyclic groups having a bulky structure with 7 or more carbon atoms, such as norbornyl, tricyclodecanyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups, are preferred.

[0164] The aryl group may be monocyclic or polycyclic. Examples of aryl groups include the phenyl group, naphthyl group, phenanthryl group, and anthryl group. The heterocyclic group may be monocyclic or polycyclic. Polycyclic groups are better able to suppress acid diffusion. The heterocyclic group may or may not be aromatic. Examples of aromatic heterocyclic groups include furan rings, thiophene rings, benzofuran rings, benzothiophene rings, dibenzofuran rings, dibenzothiophene rings, and pyridine rings. Examples of non-aromatic heterocyclic groups include tetrahydropyran rings, lactone rings, sultone rings, and decahydroisoquinoline rings. Examples of lactone and sultone rings include the lactone and sultone structures exemplified in the specific acid-degradable resin described above. Among the heterocyclic groups, furan rings, thiophene rings, pyridine rings, or decahydroisoquinoline rings are particularly preferred.

[0165] The above-mentioned cyclic organic group may have substituents. Examples of such substituents include alkyl groups (which may be linear or branched, preferably having 1 to 12 carbon atoms), cycloalkyl groups (which may be monocyclic, polycyclic, or spirocyclic, preferably having 3 to 20 carbon atoms), aryl groups (preferably having 6 to 14 carbon atoms), hydroxyl groups, alkoxy groups, ester groups, amide groups, urethane groups, ureido groups, thioether groups, sulfonamide groups, and sulfonic acid ester groups. The carbon atoms constituting the cyclic organic group (carbon atoms contributing to ring formation) may be carbonyl carbons.

[0166] An anion represented by equation (3) is, for example, SO3. - -CF2-CH2-OCO-(L)q'-W, SO3 - -CF2-CHF-CH2-OCO-(L)q'-W, SO3 - -CF2-COO-(L)q'-W, SO3 - -CF2-CF2-CH2-CH2-(L)qW, or SO3 - -CF2-CH(CF3)-OCO-(L)q'-W is preferred. Here, L, q, and W are the same as in equation (3). q' represents an integer from 0 to 10.

[0167] In one aspect, Z in equation (ZI) - , Z in equation (ZII) - , Z in equation (ZI-3) - , and X in equation (ZI-4) - As an alternative, the anion represented by the following formula (4) is also preferred.

[0168] [ka]

[0169] In formula (4), X B1 and X B2 Each of these independently represents a monovalent organic group that does not contain a hydrogen atom or a fluorine atom. B1 and X B2 It is preferable that it be a hydrogen atom. X B3 and X B4 Each of these independently represents a hydrogen atom or a monovalent organic group. B3 and X B4 Preferably, at least one of them is a fluorine atom or a monovalent organic group having a fluorine atom, X B3 and X B4 It is more preferable that both are fluorine atoms or monovalent organic groups having fluorine atoms. B3 and X B4 It is even more preferable that both are fluorine-substituted alkyl groups. L, q, and W are the same as in equation (3).

[0170] Z in equation (ZI) - , Z in equation (ZII) - , Z in equation (ZI-3) - , and X in equation (ZI-4) - As an example, the anion represented by the following formula (5) is also preferred.

[0171] [ka]

[0172] In formula (5), Xa independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. Xb independently represents a hydrogen atom or an organic group that does not have a fluorine atom. The definitions and preferred embodiments of o, p, q, R4, R5, L, and W are the same as in formula (3).

[0173] Z in equation (ZI) - , Z in equation (ZII) - , Z in equation (ZI-3) - , and X in equation (ZI-4) - This may be a benzenesulfonate anion, and it is also preferable that it be a benzenesulfonate anion substituted with a branched alkyl group or a cycloalkyl group.

[0174] Z in equation (ZI) - , Z in equation (ZII) - , Z in equation (ZI-3) - , and X in equation (ZI-4) - As an alternative, the aromatic sulfonate anion represented by the following formula (SA1) is also preferred.

[0175] [ka]

[0176] In formula (SA1), Ar represents an aryl group and may further have substituents other than a sulfonic acid anion and a -(DB) group. Examples of further substituents include a fluorine atom and a hydroxyl group.

[0177] n represents a non-negative integer. n is preferably between 1 and 4, more preferably between 2 and 3, and even more preferably 3.

[0178] D represents a single bond or a divalent linking group. Examples of divalent linking groups include ether groups, thioether groups, carbonyl groups, sulfoxide groups, sulfone groups, sulfonic acid ester groups, ester groups, and groups consisting of two or more combinations of these.

[0179] B represents a hydrocarbon group.

[0180] D is preferably a single bond, and B is preferably an aliphatic hydrocarbon structure. B is more preferably an isopropyl group or a cyclohexyl group.

[0181] Preferred examples of sulfonium cations in formula (ZI) and iodonium cations in formula (ZII) are shown below.

[0182] [ka]

[0183] [ka]

[0184] Anion Z in equation (ZI) - , the anion Z in equation (ZII) - , Z in equation (ZI-3) - , and X in equation (ZI-4) - A preferred example is shown below.

[0185] [ka] JPEG0007860117000037.jpg157156

[0186] [ka]

[0187] The above cations and anions can be used in any combination as a photoacid generator.

[0188] The photoacid generator may be in the form of a low-molecular-weight compound, or it may be incorporated as part of a polymer. Alternatively, both the low-molecular-weight compound form and the polymer-integrated form may be used in combination. The photoacid generator is preferably in the form of a low-molecular-weight compound. When the photoacid generator is in the form of a low molecular weight compound, its molecular weight is preferably 3,000 or less, more preferably 2,000 or less, and even more preferably 1,000 or less. If the photoacid generator is incorporated into a polymer, it may be incorporated into a specific acid-degradable resin as described above, or it may be incorporated into a resin different from the specific acid-degradable resin. The photoacid generator may be used alone or in combination of two or more types. In the resist composition, the content of photoacid generators (total if multiple types exist) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1.0% by mass or more, based on the total solid content of the composition. Furthermore, the upper limit is preferably 25.0% by mass or less, more preferably 20.0% by mass or less, even more preferably 15.0% by mass or less, and particularly preferably 10.0% by mass or less. Furthermore, if the resist composition contains a compound represented by the above formula (ZI-3) or (ZI-4) as a photoacid generator, it is also preferable that the amount of photoacid generator contained in the resist composition (the total amount if there are multiple types) be 5 to 35% by mass (preferably 7 to 30% by mass) of the total solid content of the composition.

[0189] The acid dissociation constant pKa of the acid (generated acid) produced when the photoacid generator decomposes upon irradiation with active light or radiation is, for example, -0.01 or less, preferably -1.00 or less, more preferably -1.50 or less, and even more preferably -2.00 or less. The lower limit of pKa is not particularly limited, but for example, it is -10.0 or more. pKa can be measured by the method described above.

[0190] <<(C) Component (Specific Polarity Conversion Compound)>> The resist composition contains a compound (specific polarity conversion compound) having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali. In other words, the resist composition contains, as a specific polarity conversion compound, a compound having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid (hereinafter also referred to as "specific polarity conversion compound A"), or a compound having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an alkali (hereinafter also referred to as "specific polarity conversion compound B"). The specific polarity conversion compound A and specific polarity conversion compound B will be described below.

[0191] <Specific polarity-converting compound A> Specific polarity-converting compound A is a compound having a fluorine atom or a silicon atom and a group (acid-degradable group) that generates a polar group upon the action of an acid. The term "group that generates a polar group upon the action of an acid" is synonymous with the acid-degradable group possessed by a specific acid-degradable resin, and the preferred embodiment is also the same. In the pattern forming method of the present invention, specific polarity conversion compound A can be decomposed by the action of acid generated during the heat treatment performed after exposure in step 2, thereby increasing its solubility in the alkaline developer. The specific polarity conversion compound A is preferably a polymer, and the polymer preferably contains repeating units (repeating unit X) having acid-degradable groups. Fluorine atoms or silicon atoms may be included in the main chain of the resin, or they may be included in the side chains.

[0192] Examples of repeating units having acid-degradable groups that specific polarity-converting compound A may contain include the following types: • A repeating unit having at least one fluorine atom and one silicon atom, and an acid-degradable group on one side chain (b A ') • Repeating units having an acid-degradable group and not containing fluorine or silicon atoms (b A *) • A repeating unit having an acid-degradable group on one side chain, and having at least one of a fluorine atom and a silicon atom on a side chain different from the above side chain within the same repeating unit (b A ")

[0193] Furthermore, specific polarity conversion compound A is a repeating unit (b A *) If it has a repeating unit having at least one of a fluorine atom and a silicon atom (the repeating unit (b A '), (b A It takes the form of a copolymer with repeating units that are different from "). Also, repeating unit (b A In the above, it is preferable that the side chain having an acid-degradable group and the side chain having at least one of a fluorine atom and a silicon atom are bonded to the same carbon atom in the main chain, that is, they are in a positional relationship as shown in the following formula (K1).

[0194] In the formula, B1 represents a substructure having the above-mentioned acid-degradable group, and B2 represents a substructure having at least one of a fluorine atom and a silicon atom.

[0195] [ka]

[0196] Specific polarity-converting compound A, in particular, has repeating units (b A ') or repeating unit (b A It is more preferable to have an asterisk (*).

[0197] In specific polarity conversion compound A, the repeating unit having an acid-degradable group is preferably the repeating unit represented by the following formula (II). In the following formula (II), the embodiment in which A represents a silicon atom is the repeating unit (b A In the embodiment where ') corresponds to and A represents a carbon atom, R in the repeating unit 11 ~R 14 If it contains a fluorine atom or a silicon atom, it is a repeating unit (b A This corresponds to ') and R in the repeating unit 11~R 14 If it does not contain fluorine atoms, it is a repeating unit (b A *) corresponds to this. [ka]

[0198] In formula (II), A represents a carbon atom or a silicon atom. 11 R represents a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. 12 , R 13 , and R 14 Each of these independently represents a linear, branched, or cyclic alkyl group, which may be substituted. 12 and R 13 These elements may be joined to each other to form a ring.

[0199] R 12 , R 13 , and R 14 Preferred linear or branched alkyl groups represented by are C1-C5 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and t-butyl groups. R 12 , R 13 , and R 14 The cyclic alkyl group represented by may be monocyclic or polycyclic. Specifically, examples include monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl groups, and polycyclic cycloalkyl groups such as norbornyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups.

[0200] R 12 and R 13 A cycloalkyl group is preferred as the ring formed by the bonding of these atoms. R 12 and R 13The cycloalkyl group formed by the bonding of these groups 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, with monocyclic cycloalkyl groups having 5 to 6 carbon atoms being more preferred. R 12 and R 13 The cycloalkyl group formed by the bonding of these groups may, for example, have one of the methylene groups constituting the ring replaced by a heteroatom such as an oxygen atom, a group having a heteroatom such as a carbonyl group, or a vinylidene group. Furthermore, in these cycloalkyl groups, one or more of the ethylene groups constituting the cycloalkane ring may be replaced by vinylene groups.

[0201] Note, R 12 , R 13 , and R 14 If all of them are linear or branched alkyl groups, 12 , R 13 , and R 14 Preferably, at least two of them are methyl groups. Also, R 12 , R 13 , and R 14 Each preferably independently represents a linear or branched alkyl group, R 12 , R 13 , and R 14 It is more preferable that each of these independently represents a linear alkyl group.

[0202] When A in formula (II) above represents a carbon atom, it is preferable that the repeating unit having an acid-degradable group takes the form of a copolymer with a repeating unit having at least one of a fluorine atom and a silicon atom.

[0203] Furthermore, when A in formula (II) above represents a carbon atom, and the repeating unit having an acid-degradable group further has a repeating unit having at least one of a fluorine atom and a silicon atom (hereinafter also referred to as "other repeating units"), it is preferable that the other repeating units have, as a substructure having a fluorine atom, a group represented by formulas (F2) to (F4) described later, or as a substructure having a silicon atom, a group represented by formulas (CS-1) to (CS-3) described later. Other repeating units are preferably (meth)acrylate-based repeating units.

[0204] [ka]

[0205] In formulas (F2) to (F4), R 57 ~R 68 Each of these independently represents a hydrogen atom, a fluorine atom, or an alkyl group (but linear or branched). However, R 57 ~R 61 At least one of R 62 ~R 64 At least one of the following, and R 65 ~R 68 At least one of these represents a fluorine atom or a fluorinated alkyl group (a group in which one or more alkyl groups are substituted with fluorine atoms, and may also be a perfluoroalkyl group; preferably has 1 to 4 carbon atoms). R 57 ~R 61 and R 65 ~R 67 Preferably, all of these are fluorine atoms. R 62 , R 63 , and R 68 As such, fluoroalkyl groups (preferably with 1 to 4 carbon atoms) are preferred, and perfluoroalkyl groups with 1 to 4 carbon atoms are more preferred. Also, R 62 and R 63 These may be connected to each other to form a ring. A preferred embodiment of the base represented by formula (F3) is R 62 and R 63 When R represents a perfluoroalkyl group, 64 One example is a hydrogen atom.

[0206] Specific examples of the group represented by formula (F2) include, for example, the p-fluorophenyl group, the pentafluorophenyl group, and the 3,5-di(trifluoromethyl)phenyl group. Specific examples of the group represented by 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, and perfluorocyclohexyl group, with hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro(2-methyl)isopropyl group, octafluoroisobutyl group, nonafluoro-t-butyl group, or perfluoroisopentyl group being more preferred, and hexafluoroisopropyl group or heptafluoroisopropyl group being even more preferred.

[0207] Specific examples of the group represented by formula (F4) include, for example, -C(CF3)2OH, -C(C2F5)2OH, -C(CF3)(CH3)OH, and -CH(CF3)OH, with -C(CF3)2OH being preferred.

[0208] [ka]

[0209] In formulas (CS-1) to (CS-3), R 12 ~R 26Each of these independently represents a linear or branched alkyl group (preferably with 1 to 20 carbon atoms, more preferably 1 to 10, and even more preferably 1 to 6 carbon atoms) or a cycloalkyl group (preferably with 3 to 20 carbon atoms, and more preferably 6 to 10 carbon atoms). L3 to L5 represent single bonds or divalent linking groups. Examples of divalent linking groups include groups consisting of one or more groups selected from the group comprising alkylene groups, phenylene groups, ether bonds, thioether bonds, carbonyl groups, ester bonds, amide bonds, urethane bonds, and ureylene bonds. n represents an integer between 1 and 5. Preferably, n is an integer between 2 and 4.

[0210] Another example of a repeating unit is the repeating unit shown below.

[0211] [ka]

[0212] In formulas (C-Ia)~(C-Id), R 10 and R 11 These can be independently a hydrogen atom, a fluorine atom, or an alkyl group (preferably having 1 to 4 carbon atoms) which may be substituted with a fluorine atom. W3 to W6 are, independently of each other, the groups represented by (F2) to (F4) above, the groups represented by (CS-1) to (CS-3) above, or *-L A -R F Examples of groups represented by the following are given. Here, L A represents a divalent linking group. Also, R F This represents the group represented by (F2) to (F4) above or the group represented by (CS-1) to (CS-3) above. L A There are no particular limitations, but examples include alkyl groups in which -CH2- is substituted with -O- or -COO-. AThe number of carbon atoms in the alkyl group represented is preferably 1 to 12, more preferably 1 to 10, and even more preferably 1 to 8.

[0213] The following are specific examples of repeating units having at least one of a fluorine atom and a silicon atom, but the present invention is not limited thereto. In the specific examples, X1 represents a hydrogen atom, -CH3, -F, or -CF3, and X2 represents -F or -CF3.

[0214] [ka]

[0215] [ka]

[0216] [ka]

[0217] In specific polarity conversion compound A, the content of the repeating unit represented by formula (II) above is preferably 5 mol% or more, and more preferably 10 mol% or more, relative to the total repeating units in specific polarity conversion compound A. As an upper limit, for example, it is preferably 60 mol% or less, and more preferably 50 mol% or less.

[0218] In specific polarity conversion compound A, the content of repeating units having fluorine atoms or silicon atoms is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, relative to the total repeating units in specific polarity conversion compound A. As an upper limit, for example, it is preferably 100 mol% or less, more preferably 80 mol% or less, and even more preferably 60 mol% or less.

[0219] The weight-average molecular weight of the specific polarity-converting compound A is preferably 1,000 to 35,000, more preferably 3,000 to 20,000, and even more preferably 3,000 to 10,000, as measured by polystyrene-based molecular weight calculation using GPC.

[0220] The specific polarity conversion compound A is preferably one that satisfies the following requirement (Requirement 1) in order to achieve superior effects of the present invention. Requirement 1: When a film (single film) made of a specific polarity conversion compound A is fully exposed under the same exposure conditions as in step 2 of the pattern formation method of the present invention, and then subjected to a heat treatment, the difference between the water contact angle of the surface of the film made of the specific polarity conversion compound A before full exposure and the water contact angle of the surface of the film made of the specific polarity conversion compound A after the heat treatment is 10° or more. The water contact angle is measured using a contact angle measuring device (manufactured by Kyowa Interface Science Co., Ltd.) in a measurement environment of 23°C and 45% relative humidity. The difference in water contact angle before and after the aforementioned heat treatment is more preferably 10° or more, and even more preferably 15° or more. The upper limit is, for example, 30° or less. Furthermore, in the measurement of requirement 1 above, baking (for example, 120°C for 60 seconds) may be performed when forming the single film.

[0221] <Specific polarity conversion compound B> Specific polarity-converting compound B is a compound that has a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an alkali (hereinafter also referred to as an "alkali-degradable group"). In the pattern formation method of the present invention, specific polarity conversion compound B can be decomposed by the action of the alkaline developer during the developing process in step 3, thereby increasing its solubility in the alkaline developer. The specific polarity conversion compound B is preferably a polymer, and the polymer preferably contains repeating units (repeating unit X) having alkali-degradable groups. Fluorine atoms or silicon atoms may be included in the main chain of the resin, or they may be included in the side chains.

[0222] Examples of repeating units having alkali-degradable groups that specific polarity-converting compound B may contain include the following types: • A repeating unit having at least one fluorine atom and one silicon atom, and an alkali-degradable group on one side chain (b B ') • Repeating units having an alkali-degradable group and not containing fluorine or silicon atoms (b B *) • A repeating unit having an alkali-degradable group on one side chain, and having at least one of a fluorine atom and a silicon atom on a side chain different from the above side chain within the same repeating unit (b B ")

[0223] Specific polarity-converting compound B, in particular, has repeating units (b B It is more preferable to have '). Furthermore, specific polarity conversion compound B is a repeating unit (b B *) If it has a repeating unit having at least one of a fluorine atom and a silicon atom (the repeating unit (b B '), (b B It takes the form of a copolymer with repeating units that are different from "). Also, repeating unit (b B In the above, it is preferable that the side chain having an alkali-degradable group and the side chain having at least one of a fluorine atom and a silicon atom are bonded to the same carbon atom in the main chain, that is, they are in a positional relationship as shown in the following formula (K1).

[0224] In the formula, B1 represents a substructure having the alkali-degradable group described above, and B2 represents a substructure having at least one of a fluorine atom and a silicon atom.

[0225] [ka]

[0226] Examples of alkali-degradable groups include lactone groups, carboxylic acid ester groups (-COO-), acid anhydride groups (-C(O)OC(O)-), acid imide groups (-NHCONH-), carboxylic acid thioester groups (-COS-), carbonate ester groups (-OC(O)O-), sulfate ester groups (-OSO2O-), and sulfonic acid ester groups (-SO2O-), with lactone groups being preferred. The alkali-degradable group is preferably introduced into the side chain of the resin by being included in, for example, a repeating unit made of (meth)acrylic acid ester, or introduced into the end of the polymer chain by using a polymerization initiator or chain transfer agent having an alkali-degradable group during polymerization. An example of a repeating unit having an alkali-degradable group is a repeating unit having a lactone structure represented by formulas (KA-1-1) to (KA-1-17), which will be described later.

[0227] Furthermore, the repeating unit having an alkali-degradable group is a repeating unit having at least one of a fluorine atom and a silicon atom (i.e., the repeating unit (b B '), (b B (This corresponds to "") which is preferable. An example of a repeating unit having an alkali-degradable group is the repeating unit represented by formula (K0).

[0228] [ka]

[0229] In the formula, R k1 This represents a group containing a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, a cycloalkyl group, an aryl group, or an alkali-degradable group. R k2 This represents a group containing an alkyl group, cycloalkyl group, aryl group, or alkali-degradable group. However, R k1 , and R k2 At least one of them represents a group containing an alkali-degradable group. The alkali-degradable group is preferably the group represented by X in the substructure represented by formula (KA-1) or (KB-1).

[0230] [ka]

[0231] In formula (KA-1) or (KB-1), X represents a carboxylic acid ester group: -COO-, an acid anhydride group: -C(O)OC(O)-, an acid imide group: -NHCONH-, a carboxylic acid thioester group: -COS-, a carbonate ester group: -OC(O)O-, a sulfate ester group: -OSO2O-, and a sulfonic acid ester group: -SO2O-.

[0232] Y 1 and Y 2 Each of these independently represents an electron-withdrawing group. Furthermore, the repeating unit having an alkali-degradable group has a structure in which an alkali-degradable group is introduced into the repeating unit by having a group having a substructure represented by formula (KA-1) or (KB-1), but the substructure represented by formula (KA-1), and Y 1 and Y 2 In the case of a substructure represented by formula (KB-1) when it is monovalent, if the substructure does not have a bond, then the group having the substructure is a group having a monovalent or greater group with at least one hydrogen atom removed from the substructure.

[0233] The substructure represented by formula (KA-1) or (KB-1) is linked to the main chain of a specific polarity-converting compound B directly or via substituents at any position. The substructure represented by formula (KA-1) is a structure that forms a ring structure together with the group X. In formula (KA-1), X is preferably a carboxylic acid ester group (i.e., when KA-1 forms a lactone ring structure), an acid anhydride group, or a carbonate ester group, with a carboxylic acid ester group being more preferred.

[0234] The ring structure represented by formula (KA-1) may have substituents, for example, substituent Z ka1 It may have nka instances of this. Z ka1 If there are multiple instances, each independently represents a halogen atom, alkyl group, cycloalkyl group, ether group, hydroxyl group, amide group, aryl group, lactone ring group, or electron-withdrawing group. Also, Z ka1 They may be connected to each other to form a ring. ka1 Examples of rings formed by the linking of these elements include cycloalkyl rings and heterocycles (such as cyclic ether rings and lactone rings). nka represents an integer between 0 and 10, preferably between 0 and 8, more preferably between 0 and 5, even more preferably between 1 and 4, and particularly preferably between 1 and 3. Z ka1 The electron-withdrawing group is Y, which will be discussed later. 1 and Y 2 This is similar to an electron-withdrawing group. Note that the above electron-withdrawing group may be substituted with another electron-withdrawing group. Z ka1 Preferably, alkyl groups, cycloalkyl groups, ether groups, hydroxyl groups, or electron-withdrawing groups are used, and alkyl groups, cycloalkyl groups, or electron-withdrawing groups are more preferred. As for ether groups, those substituted with alkyl groups or cycloalkyl groups, i.e., alkyl ether groups, etc., are preferred. Electron-withdrawing groups are described later as Y 1 and Y 2 It is similar to an electron-withdrawing group. Z ka1 Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms, with fluorine being preferred.

[0235] Z ka1 The alkyl group may have substituents and may be linear or branched. The number of carbon atoms in the linear alkyl group is preferably 1 to 30, and more preferably 1 to 20. The branched alkyl group preferably has 3 to 30 carbon atoms, and more preferably 3 to 20 carbon atoms. The branched alkyl group is preferably one with 1 to 4 carbon atoms, such as a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, and t-butyl group.

[0236] Z ka1 The cycloalkyl group may have substituents, be monocyclic, or polycyclic. In the case of polycyclic compounds, the cycloalkyl group may be bridged. That is, in this case, the cycloalkyl group may have a cross-linked structure. As monocyclic groups, cycloalkyl groups having 3 to 8 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cyclobutyl, and cyclooctyl groups, are preferred. Examples of polycyclic groups include bicyclo, tricyclo, and tetracyclo structures with 5 or more carbon atoms. Among these, cycloalkyl groups with 6 to 20 carbon atoms, such as adamantyl, norbornyl, isobolonyl, camphanyl, dicyclopentyl, α-pinel, tricyclodecanyl, tetocyclododecyl, and androstanyl groups, are preferred. Furthermore, the cycloalkyl group is preferably derived from the cycloalkanes shown below. At least one carbon atom in the cycloalkane may be substituted with a heteroatom such as an oxygen atom.

[0237] [ka]

[0238] The groups derived from the above cycloalkanes (cycloalkyl groups) are preferably adamantyl, noradamantyl, decalin, tricyclodecanyl, tetracyclododecanyl, norbornyl, cedrol, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecanyl, or cyclododecanyl, and more preferably adamantyl, decalin, norbornyl, cedrol, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecanyl, cyclododecanyl, or tricyclodecanyl.

[0239] The group derived from the above cycloalkane (cycloalkyl group) may have substituents, and examples of substituents include alkyl groups, halogen atoms, hydroxyl groups, alkoxy groups, carboxyl groups, and alkoxycarbonyl groups. The number of carbon atoms in the alkyl group, alkoxy group, and alkoxycarbonyl group is preferably 1 to 6, and more preferably 1 to 4. Furthermore, the alkyl group, alkoxy group, and alkoxycarbonyl group may have substituents, and examples of substituents include hydroxyl groups, halogen atoms, and alkoxy groups (preferably with 1 to 4 carbon atoms).

[0240] Furthermore, the above group may have further substituents, and examples of further substituents include hydroxyl groups, halogen atoms (fluorine, chlorine, bromine, iodine), nitro groups, cyano groups, alkyl groups, alkoxy groups, alkoxycarbonyl groups, aralkyl groups, acyl groups, alkenyl groups, alkenyloxy groups, aryl groups, aryloxy groups, and aryloxycarbonyl groups.

[0241] It is preferable that X in formula (KA-1) is a carboxylic acid ester group and the substructure represented by formula (KA-1) is a lactone ring, and it is more preferable that X in formula (KA-1) is a carboxylic acid ester group and the substructure represented by formula (KA-1) is a 5- to 7-membered lactone ring.

[0242] Furthermore, as shown in (KA-1-1) to (KA-1-17) below, it is preferable that other ring structures are fused to the 5- to 7-membered lactone ring, which is a substructure represented by formula (KA-1), in a manner that forms a bicyclo or spiro structure.

[0243] The structure represented by formula (KA-1) having a lactone ring structure is preferably selected from the group consisting of (KA-1-1) to (KA-1-17) below, with (KA-1-1), (KA-1-4), (KA-1-5), (KA-1-6), (KA-1-13), (KA-1-14), or (KA-1-17) being more preferred. Furthermore, the structure represented by formula (KA-1), which has a lactone ring structure, may be directly bonded to the main chain.

[0244] [ka]

[0245] The above (KA-1-1) to (KA-1-17) may have further substituents. The substituent may be substituent Z, which may be present in the ring structure represented by formula (KA-1). ka1 Similar examples include the above.

[0246] Furthermore, when the structure represented by formula (KA-1), which has a lactone ring structure, represents a monovalent group, it is preferable that one hydrogen atom from the member atom of the lactone ring is removed to form a bond. Also, when it represents a divalent group, it is preferable that two hydrogen atoms from the member atoms of the lactone ring are removed to form a bond.

[0247] In formula (KB-1), X is preferably a carboxylic acid ester group (-COO-).

[0248] Y in equation (KB-1) 1 and Y 2 Each of these independently represents an electron-withdrawing group. Examples of electron-withdrawing groups include the group represented by the following formula (EW). In formula (EW), * represents a bond directly connected to (KA-1) or a bond directly connected to X in (KB-1).

[0249] [ka]

[0250] In formula (EW), R ew1 and R ew2 Each of these independently represents a hydrogen atom or a substituent. Preferably, the substituent is an alkyl group, a cycloalkyl group, or an aryl group. n ew -C(R ew1 )(R ew2 n is the number of repetitions of the linking base represented by )-, and represents an integer of 0 or 1. ew If it is 0, it represents a single bond, and directly Y ew1 This indicates that they are joined together.

[0251] Y ew1 These are halogen atoms, cyano groups, nitrile groups, nitro groups, and -C(R f1 )(R f2 )-R f3 This represents a monovalent group, or a bond, of a halo(cyclo)alkyl group, haloaryl group, oxy group, ether group, carbonyl group, sulfonyl group, sulfinyl group, or combination thereof. Furthermore, "halo(cyclo)alkyl group" refers to alkyl and cycloalkyl groups that are at least partially halogenated, and "haloaryl group" refers to an aryl group that is at least partially halogenated.

[0252] Furthermore, the electron-withdrawing group may also have the following structural formula, for example. In the following structural formula, R ew3 and R ew4 Each of these independently represents an arbitrary structure. ew3 and R ew4Regardless of the structure, the parts derived from the substructure represented by formula (EW) are electron-withdrawing. ew3 and R ew4 For example, it may be a bond that connects to the main chain of the resin, or it may represent an alkyl group, a cycloalkyl group, or a fluorinated alkyl group.

[0253] [ka]

[0254] Y ew1 When represents a bonding site, the bonding site forms a bond with any atom or substituent. ew1 , R ew1 , R ew2 At least one of the groups may be linked to the main chain of the specific polarity-converting compound B via further substituents.

[0255] Y ew1 Examples include ether groups, carbonyl groups, halogen atoms, and -C(R f1 )(R f2 )-R f3 It is preferable that the group is a combination of one or more selected from the group consisting of a halo(cyclo)alkyl group represented by -COO-C(R f1 )(R f2 )-R f3 A -COO-haloaryl group is more preferred. Also, R ew4 Examples include halogen atoms, -C(R f1 )(R f2 )-R f3 Preferably, it is a halo(cyclo)alkyl group or a haloaryl group represented by . Here R f1 It is preferable that represents a halogen atom, a perhaloalkyl group, a perhalocycloalkyl group, or a perhaloaryl group, more preferably a fluorine atom, a perfluoroalkyl group, or a perfluorocycloalkyl group, and even more preferably a fluorine atom or a trifluoromethyl group. R f2 and Rf3 Each of these independently represents a hydrogen atom, a halogen atom, or an organic group. Examples of the above organic groups include alkyl groups, cycloalkyl groups, or alkoxy groups, and examples of perhaloalkyl groups, perhalocycloalkyl groups, and perhaloaryl groups. R f1 , R f2 , and R f3 In R f2 For example, R f1 It represents the same group as R f3 It is preferable that they are connected to form a ring.

[0256] Note, R f2 and R f3 These may be joined together to form a ring. R f2 and R f3 Examples of rings formed by the bonding of these elements include (halo)cycloalkyl rings and (halo)aryl rings. R f1 ~R f3 Examples of (halo)alkyl groups in this context include the Z mentioned above. ka1 Examples include alkyl groups in the compound, and halogenated structures thereof. R f1 ~R f3 In, or R f2 and R f3 Examples of the (per)halocycloalkyl group and (per)haloaryl group in the ring formed by the bonding of these groups to each other include the Z group mentioned above. ka1 One example is a structure in which the cycloalkyl group in the following is halogenated: -C (n) F (2n-2) A fluorocycloalkyl group represented by H, or -C (n) F (n-1) A perfluoroaryl group represented by is preferred. Here, the number of carbon atoms n is not particularly limited, but 5 to 13 is preferred, and 6 is more preferred.

[0257] Also, R ew1 , R ew2 , and Y ew1At least two of these may be connected to each other to form a ring. R ew1 , R ew2 and Y ew1 A cycloalkyl group or a heterocyclic group is preferred as the ring that may be formed by the bonding of at least two of the elements. A lactone ring group is preferred as the heterocyclic group. Examples of lactone rings include the structures represented by the above formulas (KA-1-1) to (KA-1-17).

[0258] Furthermore, the repeating unit having an alkali-degradable group may contain multiple substructures represented by formula (KA-1), multiple substructures represented by formula (KB-1), or both substructures represented by formula (KA-1) and substructures represented by formula (KB-1). Furthermore, some or all of the substructure of formula (KA-1) is Y in formula (KB-1). 1 or Y 2 It may also serve as an electron-withdrawing group. For example, if X in formula (KA-1) is a carboxylic acid ester group, then that carboxylic acid ester group is Y in formula (KB-1). 1 or Y 2 It can also function as an electron-withdrawing group.

[0259] Furthermore, the repeating unit having an alkali-degradable group is the repeating unit (b B *) or repeating unit (b B If the substance falls under the category of ") and has a substructure represented by formula (KA-1), it is more preferable that the substructure represented by formula (KA-1) is a substructure represented by -COO- in the structure shown by formula (KA-1) in which the alkali-degradable group is. A repeating unit having an alkali-degradable group may be a repeating unit having a substructure represented by formula (KY-0).

[0260] [ka]

[0261] In formula (KY-0), R2 represents a linear, branched, or cyclic alkylene group, and if there are multiple R2 groups, they may be the same or different. R3 represents a linear, branched, or cyclic hydrocarbon group in which some or all of the hydrogen atoms on the constituent carbon are replaced by fluorine atoms. R4 represents a halogen atom, a cyano group, a hydroxyl group, an amide group, an alkyl group, a cycloalkyl group, an alkoxy group, a phenyl group, an acyl group, an alkoxycarbonyl group, or a group represented by RC(=O)- or RC(=O)O- (where R represents an alkyl group or a cycloalkyl group). If there are multiple R4s, they may be the same or different, and two or more R4s may be bonded together to form a ring. X represents an alkylene group, an oxygen atom, or a sulfur atom. Z and Za each independently represent a single bond, ether bond, ester bond, amide bond, urethane bond, or urea bond, and if there are multiple, they may be the same or different. * indicates a bond to the main chain or side chain of specific polarity-converting compound B. 'o' represents the number of substituents and is an integer between 1 and 7. m represents the number of substituents and is an integer between 0 and 7. n represents the repeating number and can be an integer from 0 to 5.

[0262] The -R2-Z- structure is preferably -(CH2) l A structure represented as -COO- is preferred (where l represents an integer from 1 to 5).

[0263] The number of carbon atoms in the linear or branched alkylene group represented by R2 is preferably 1 to 30, more preferably 1 to 20, even more preferably 1 to 10, and particularly preferably 1 to 6. The number of carbon atoms in the cyclic alkylene group represented by R2 is preferably 6 to 20, and more preferably 6 to 10.

[0264] The number of carbon atoms in the linear and branched hydrocarbon groups as R3 is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 10. The number of carbon atoms in the cyclic hydrocarbon group as R3 is preferably 6 to 20, and more preferably 6 to 10. A concrete example of R3 is the aforementioned Z ka1 Examples of alkyl and cycloalkyl groups can be found similar to those mentioned above.

[0265] The preferred number of carbon atoms and specific examples of alkyl and cycloalkyl groups as R4 and R are as described above for Z ka1 The same applies to alkyl and cycloalkyl groups as described above.

[0266] The acyl group R4 is preferably one having 1 to 6 carbon atoms, such as the formyl group, acetyl group, propionyl group, butyryl group, isobutyryl group, valeryl group, and pivaloyl group. Examples of alkyl moieties in the alkoxy group and alkoxycarbonyl group as R4 include linear, branched, or cyclic alkyl moieties, and preferred carbon number and specific examples of the alkyl moiety are as described above in Z. ka1 The same applies to alkyl and cycloalkyl groups as described above.

[0267] Examples of alkylene groups as X include linear, branched, or cyclic alkylene groups, and their carbon number and specific examples are the same as those described for the linear, branched, or cyclic alkylene group represented by R2.

[0268] Furthermore, it is more preferable that the repeating unit having an alkali-degradable group has at least two or more alkali-degradable groups.

[0269] When a repeating unit having an alkali-degradable group has at least two alkali-degradable groups, it is preferable that it has a group having a substructure with two alkali-degradable groups, as shown by the following formula (KY-1). If the structure represented by formula (KY-1) does not have bonds, it is a group having a monovalent or greater group with at least one hydrogen atom removed from the above structure.

[0270] [ka]

[0271] In equation (KY-1), R ky1 and R ky4 Each independently represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, a carbonyl group, a carbonyloxy group, an oxycarbonyl group, an ether group, a hydroxyl group, a cyano group, an amide group, or an aryl group, or R ky1 and R ky4 It bonds with the same atom to form a double bond. ky1 and R ky4 One example of a configuration in which R bonds with the same atom to form a double bond is, ky1 and R ky4 This refers to the mode in which it bonds with the same oxygen atom to form part of a carbonyl group (=O). R ky2 and R ky3 Each of these independently represents an electron-withdrawing group, or R ky1 and R ky2 They are linked to form a lactone ring, and R ky3 This represents an electron-withdrawing group. ky1 and R ky2 When these are linked to form a lactone ring, the lactone ring is preferably the structure represented by (KA-1-1) to (KA-1-17) described above. Furthermore, the electron-withdrawing group can be the same as Y1 and Y2 in formula (KB-1), and may include a halogen atom, -C(R f1 )(R f2 )-R f3A halo(cyclo)alkyl group or haloaryl group represented by is preferred. R ky1 , R ky2 , and R ky3 A preferred embodiment of this is R ky3 However, halogen atoms, as mentioned above -C(R f1 )(R f2 )-R f3 A halo(cyclo)alkyl group or haloaryl group represented by R ky2 and R ky1 Either R and R are bonded together to form a lactone ring, or ky1 , R ky2 , and R ky3 However, all of these represent electron-withdrawing groups that do not contain halogen atoms. R ky1 , R ky2 , and R ky4 These elements may be linked to each other to form a monocyclic or polycyclic structure.

[0272] R ky1 and R ky4 A concrete example of this is Z in equation (KA-1). ka1 Similar bases can be cited.

[0273] R ky1 and R ky2 The lactone ring formed by the bonding of these groups is preferably structured as (KA-1-1) to (KA-1-17) above. Examples of electron-withdrawing groups include those similar to Y1 and Y2 in formula (KB-1) above.

[0274] The structure represented by formula (KY-1) is more preferably the structure shown in formula (KY-2) below. The structure represented by formula (KY-2) is a group having one or more valent groups, with at least one hydrogen atom removed from the above structure.

[0275] [ka]

[0276] In formula (KY-2), R ky6 ~R ky10 Each of these independently represents a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, a carbonyl group, a carbonyloxy group, an oxycarbonyl group, an ether group, a hydroxyl group, a cyano group, an amide group, or an aryl group. R ky6 ~R ky10 Two or more of these elements may be linked to each other to form a monocyclic or polycyclic structure. R ky5 represents an electron-withdrawing group. Examples of electron-withdrawing groups are the same as those mentioned above for Y1 and Y2, including halogen atoms and the -C(R) group mentioned above. f1 )(R f2 )-R f3 A halo(cyclo)alkyl group or haloaryl group represented by is preferred. R ky5 ~R ky10 Specifically, Z in equation (KA-1) ka1 Similar bases can be cited. The structure represented by formula (KY-2) is more preferably a substructure shown by formula (KY-3) below.

[0277] [ka]

[0278] In formula (KY-3), Z ka1 nka is equivalent to the above formula (KA-1), respectively. ky5 This is equivalent to the above equation (KY-2). L ky L represents an alkylene group, an oxygen atom, or a sulfur atom. ky Examples of alkylene groups represented by include methylene groups and ethylene groups. ky Preferably, it is an oxygen atom or a methylene group, and more preferably a methylene group.

[0279] As a preferred embodiment of the repeating unit having an alkali-degradable group of the specific polarity conversion compound B, it is also preferable that the repeating unit is represented by the following formula (III).

[0280] [ka]

[0281] In formula (III), L represents a divalent organic group. 21 R represents a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. 22 represents a monovalent organic group. However, the repeating unit represented by formula (III) includes a structural site (alkali-degradable site) that generates a polar group through the action of a fluorine atom and alkali.

[0282] Examples of alkali-degradable parts include L and R in formula (III). 22 If at least one of them has an alkali-degradable group, this alkali-degradable group may be applicable. Also, the -COOR explicitly shown in formula (III) 22 In R 22 If L has a strong electron-withdrawing group (e.g., perfluoroalkyl group and hexafluoroisopropyl group) and L has, for example, a lactone group, then -COOR 22 These may also be considered alkaline-degradable parts.

[0283] Examples of alkali-degradable groups include the alkali-degradable groups described above (for example, lactone groups, carboxylic acid ester groups (-COO-), acid anhydride groups (-C(O)OC(O)-), acid imide groups (-NHCONH-), carboxylic acid thioester groups (-COS-), carbonate ester groups (-OC(O)O-), sulfate ester groups (-OSO2O-), and sulfonic acid ester groups (-SO2O-), etc.).

[0284] A preferred embodiment of the repeating unit represented by formula (III) is a repeating unit represented by formula (III) in which L represents a divalent organic group and R 22 One embodiment is one in which at least one of the monovalent organic groups represented by has an alkali-degradable group. A more preferred embodiment of the repeating unit represented by formula (III) is one in which the divalent organic group represented by L contains an alkali-degradable group, and R 22 One example is a configuration in which the monovalent organic group represented by contains a fluorine atom.

[0285] In formula (III), R 22 The monovalent organic group represented by is not particularly limited and includes alkyl groups, cycloalkyl groups, and aryl groups. The number of carbon atoms in the alkyl group is preferably 1 to 25, more preferably 1 to 20, even more preferably 1 to 12, and particularly preferably 1 to 6. The cycloalkyl groups mentioned above are preferably monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl groups, and polycyclic cycloalkyl groups such as norbornyl, tetracyclodecanyl, tetracyclododecanyl, and adamantyl groups. The number of carbon atoms in the cycloalkyl group is preferably 5 to 20, and more preferably 5 to 15. The aryl group mentioned above is preferably an aryl group having 6 to 10 carbon atoms, such as a phenyl group, a naphthyl group, and an anthyl group. Alkyl, cycloalkyl, and aryl groups further represent substituents. The substituents are not particularly limited; for example, a fluorine atom can be used.

[0286] R 22 Among the monovalent organic groups represented, it is preferable that they represent linear, branched, or cyclic alkyl groups having a fluorine atom. R 22 Linear and branched alkyl groups having fluorine atoms, as represented by , include linear and branched alkyl groups in which some or all of the hydrogen atoms are substituted with fluorine atoms. The number of carbon atoms is preferably 1 to 25, more preferably 1 to 20, even more preferably 1 to 12, and particularly preferably 1 to 6. R 22Examples of cyclic alkyl groups having fluorine atoms represented by include cyclic alkyl groups in which some or all of the hydrogen atoms are replaced with fluorine atoms. The number of carbon atoms is preferably 6 to 20, and more preferably 6 to 10.

[0287] The divalent organic group represented by L is not particularly limited and includes, for example, alkylene groups (preferably having 1 to 20 carbon atoms; may be linear or branched), cycloalkylene groups (preferably having 6 to 20 carbon atoms), aryl groups (preferably aromatic ring groups with 6 to 10 ring members), and divalent linking groups formed by combining several of these. The methylene group in the alkylene group and the methylene group constituting the ring in the cycloalkylene group are -O-, -NR A They may be substituted with heteroatoms such as - and -S-, and with groups having heteroatoms such as >C(=O) and -SO2-. Furthermore, alkylene groups, cycloalkylene groups, and aryl groups may have further substituents. Examples of substituents include halogen atoms (preferably fluorine atoms) and hydroxyl groups. A Examples include hydrogen atoms or alkyl groups having 1 to 6 carbon atoms. Among the divalent organic groups represented by L, divalent organic groups containing the above-mentioned alkali-degradable groups (for example, lactone groups, carboxylic acid ester groups (-COO-), acid anhydride groups (-C(O)OC(O)-), acid imide groups (-NHCONH-), carboxylic acid thioester groups (-COS-), carbonate ester groups (-OC(O)O-), sulfate ester groups (-OSO2O-), and sulfonic acid ester groups (-SO2O-), etc.) are preferred, and organic groups containing divalent groups formed by removing two hydrogen atoms in the substructure represented by formula (KA-1) above are more preferred. The substructure represented by formula (KA-1) above is preferably a 5- to 7-membered lactone ring. The substructure represented by formula (KA-1) and its preferred embodiments are as previously described.

[0288] For example, L is * 1 -L 11 -L 12 -* 2 A divalent organic group represented by is also preferred. L 11 This represents a single bond or a divalent linking group. L 11 The divalent linking group represented by is not particularly limited, but for example, -CO-, -O-, -SO-, -SO2-, -NR A -, alkylene groups (preferably having 1 to 6 carbon atoms; may be linear or branched), cycloalkylene groups (preferably having 3 to 15 carbon atoms), arylene groups (preferably 6 to 10-membered rings, more preferably 6-membered rings), and divalent linking groups formed by combining multiples thereof. Furthermore, the alkylene groups, cycloalkylene groups, and arylene groups may have substituents. Examples of substituents include halogen atoms (preferably fluorine atoms) and hydroxyl groups. A Examples include hydrogen atoms or alkyl groups having 1 to 6 carbon atoms.

[0289] L 12 This represents a divalent group formed by removing two hydrogen atoms from the substructure represented by formula (KA-1) described above. The substructure represented by formula (KA-1) is preferably a 5- to 7-membered lactone ring. The substructure represented by formula (KA-1) and its preferred embodiments are as previously described.

[0290] * 1 * represents the bond position with the ester group linked to the main chain. 2 This represents the bonding position with the other ester group explicitly shown in formula (II).

[0291] The repeating units having alkali-degradable groups are preferably acrylate-based repeating units (including those with substituents at the α and β positions), styrene-based repeating units (including those with substituents at the α and β positions), vinyl ether-based repeating units, norbornene-based repeating units, and maleic acid derivatives (maleic anhydride and its derivatives, maleimide, etc.), with acrylate-based repeating units being more preferable.

[0292] When the repeating unit having an alkali-degradable group is a repeating unit having at least one of a fluorine atom and a silicon atom (i.e., the repeating unit (b B ') or (b B In the case corresponding to "), the substructure having a fluorine atom in the repeating unit having an alkali-degradable group may have a group represented by formulas (F2) to (F4) described above in the specific polarity conversion compound A, or it is also preferable that the substructure having a silicon atom in the repeating unit having an alkali-degradable group may have a group represented by formulas (CS-1) to (CS-3) described above in the specific polarity conversion compound A.

[0293] The specific polarity conversion compound B may contain other repeating units besides the alkali-degradable group for the purpose of adjusting its uneven distribution on the film surface. Other repeating units include, for example, repeating units having 5 or more carbon atoms (preferably 5 to 20 carbon atoms) and a hydrocarbon group having a CH3 substructure in its side chain. Examples of repeating units having a hydrocarbon group with 5 or more carbon atoms and a CH3 substructure in its side chain include repeating units in which these groups are directly bonded to the main chain, as well as repeating units made of acrylic acid esters and methacrylic acid esters. The hydrocarbon group is preferably one or more groups selected from the group consisting of aromatic hydrocarbon ring groups and alkyl groups (which may be linear, branched, or cyclic).

[0294] The content of repeating units having alkali-degradable groups in specific polarity conversion compound B is preferably 10 to 100 mol%, more preferably 20 to 99 mol%, even more preferably 30 to 97 mol%, and particularly preferably 40 to 95 mol%, relative to the total repeating units in specific polarity conversion compound B. The following are specific examples of repeating units having alkali-degradable groups, but are not limited to these.

[0295] In the specific examples shown below, Ra represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

[0296] [ka]

[0297] [ka]

[0298] As a method for synthesizing monomers corresponding to repeating units having alkali-degradable groups as described above, for example, the method described in International Publication No. 2010 / 067905 or the method described in International Publication No. 2010 / 067905, etc., can be used as a reference.

[0299] In specific polarity conversion compound B, the content of repeating units having fluorine atoms or silicon atoms is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, relative to the total repeating units in specific polarity conversion compound B. As an upper limit, for example, it is preferably 100 mol% or less, and more preferably 80 mol% or less.

[0300] The weight-average molecular weight of the specific polarity-converting compound B is preferably 1,000 to 35,000, more preferably 3,000 to 20,000, and even more preferably 3,000 to 10,000, as measured by GPC (Glycerin-based molecular weight conversion).

[0301] The specific polarity conversion compound B is preferably one that satisfies the following requirement (Requirement 2) in that it provides superior effects for the present invention. Requirement 2: When a film (single film) made of specific polarity conversion compound B is brought into contact with the alkaline developer used in step 3, the difference between the water contact angle of the surface of the film (single film) made of specific polarity conversion compound B that is in contact with the alkaline developer and the water contact angle of the surface of the film (single film) made of specific polarity conversion compound B after contact with the alkaline developer is 10° or more. The water contact angle is measured using a contact angle measuring device (manufactured by Kyowa Interface Science Co., Ltd.) in a measurement environment of 23°C and 45% relative humidity. The difference in the water contact angle before and after contact with the alkaline developer is more preferably 10° or more, and even more preferably 15° or more. The upper limit is, for example, 30° or less. Furthermore, when bringing the single film into contact with the alkaline developer used in step 3 during the measurement of requirement 2 above, it is preferable to use the same conditions for the alkaline development in step 3 during pattern formation (processing time, etc.). Also, if a rinsing treatment is performed after the alkaline development treatment in step 3 during pattern formation, it is preferable to perform the same rinsing treatment during the measurement of requirement 2 as well. Furthermore, in the measurement of requirement 2 above, baking (for example, 120°C for 60 seconds) may be performed when forming the single film.

[0302] The specific polarity conversion compound may be used alone or in combination of two or more types. In the resist composition, the content of specific polarity conversion compounds (the total if multiple types exist) is preferably 0.01% by mass or more, and more preferably 0.1% by mass or more, relative to the total solid content of the composition. Furthermore, the upper limit is preferably 10.0% by mass or less, more preferably 8.0% by mass or less, even more preferably 5.0% by mass or less, and particularly preferably 3.0% by mass or less.

[0303] <<(D) Component (Solvent)>> The resist composition contains a solvent. The solvent preferably contains at least one solvent selected from (M1) below and at least one solvent selected from (M2) below, and more preferably contains a solvent selected from (M1) below and at least one solvent selected from (M2) below. (M1) Propylene glycol monoalkyl ether carboxylate (M2) Propylene glycol monoalkyl ether, lactate ester, acetate ester, alkoxypropionic acid ester, linear ketone, cyclic ketone, lactone, alkylene carbonate Furthermore, in terms of achieving superior effects of the present invention, it is even more preferable to include at least two solvents selected from (M1) and (M2), particularly preferably propylene glycol monoalkyl ether carboxylate, propylene glycol monoalkyl ether, and lactone, and most preferably propylene glycol monoalkyl ether carboxylate, propylene glycol monoalkyl ether, and γ-butyrolactone.

[0304] When the above-mentioned solvent is used in combination with a specific acid-degradable resin, the coatability of the resist composition is improved, and patterns with fewer development defects can be formed. This is presumed to be because the above-mentioned solvent has a good balance of solubility, boiling point, and viscosity with the specific acid-degradable resin, which makes it easier to suppress unevenness in the thickness of the resist film and the generation of precipitates during spin coating. Details of components (M1) and (M2) are described in paragraphs

[0218] to

[0226] of International Publication No. 2020 / 004306, and this content is incorporated into the specification of the present invention.

[0305] Furthermore, the solvent may also contain solvents other than those selected from (M1) and (M2) (hereinafter also referred to as "other solvents"). If the solvent further contains other solvents, the content of the other solvents is preferably 5.0 to 30.0% by mass relative to the total amount of the solvent.

[0306] <<(E) Component (Acid Diffusion Control Agent)>> The resist composition may further contain an acid diffusion control agent. The acid diffusion control agent traps the acid generated from photoacid generators during exposure and acts as a quencher to suppress the reaction of acid-degradable resins in unexposed areas due to excess generated acid. In the resist composition used in the pattern formation method of the present invention, known acid diffusion control agents can be used as appropriate. For example, known compounds disclosed in paragraphs

[0627] to

[0664] of U.S. Patent Application Publication 2016 / 0070167A1, paragraphs

[0095] to

[0187] of U.S. Patent Application Publication 2015 / 0004544A1, paragraphs

[0403] to

[0423] of U.S. Patent Application Publication 2016 / 0237190A1, and paragraphs

[0259] to

[0328] of U.S. Patent Application Publication 2016 / 0274458A1 can be suitably used as acid diffusion control agents. Other examples include the basic compounds described in paragraphs

[0132] to

[0136] of International Publication No. 2020 / 066824, and the onium salt compounds having a nitrogen atom in the cation portion described in paragraph

[0164] of International Publication No. 2020 / 066824.

[0307] Furthermore, an onium salt (hereinafter also referred to as "compound (CQ1)") which is a relatively weak acid with respect to the photoacid generating component can also be used as an acid diffusion control agent. When a photoacid generator and an onium salt that generates an acid that is relatively weak to the acid produced by the photoacid generator are used together, when the acid produced by the photoacid generator collides with the onium salt containing an unreacted weak acid anion due to irradiation with active light or radiation, salt exchange occurs, releasing the weak acid and producing an onium salt containing a strong acid anion. In this process, the strong acid is exchanged for a weaker acid with lower catalytic activity, so the acid is seemingly deactivated and acid diffusion can be controlled.

[0308] As compound (CQ1), compounds represented by the following formulas (d1-1) to (d1-3) are preferred.

[0309] [ka]

[0310] In the formula, R 51 It is an organic group. The number of carbon atoms is preferably 1 to 30. Z 2cis an organic group. The number of carbon atoms in the above organic group is preferably 1 to 30. However, Z 2c The organic group represented by the formula is SO, which is explicitly shown in the formula. 3- When a carbon atom is adjacent to it, this carbon atom (α-carbon atom) does not have a fluorine atom and / or a perfluoroalkyl group as substituents. The above α-carbon atom is not a ring member atom of a cyclic structure and is preferably a methylene group. Also, Z 2c Medium, SO3 - If the atom at the β position is a carbon atom (β-carbon atom), then the β-carbon atom also does not have a fluorine atom and / or a perfluoroalkyl group as substituents. R 52 Y is an organic group (alkyl group, etc.), 3 is a -SO2-, linear, branched, or cyclic alkylene group, or an arylene group, Y 4 Rf is a hydrocarbon group containing a fluorine atom (such as a fluoroalkyl group), where -CO- or -SO2- is present.

[0311] M + Each of these is independently an ammonium cation, a sulfonium cation, or an iodonium cation. M in formulas (d1-1) to (d1-3) + For example, cations in compounds represented by formula (ZI) and cations in compounds represented by formula (ZII) can also be used.

[0312] Furthermore, basic compounds (hereinafter referred to as "compound (CQ2)") that have a nitrogen atom and whose basicity decreases or disappears upon irradiation with active light or radiation can also be used as acid diffusion control agents. Compound (CQ2) is a compound that has a proton-accepting functional group and decomposes upon irradiation with active light or radiation, resulting in a decrease or disappearance of its proton-accepting properties, or a change from proton-accepting properties to acidic properties.

[0313] A proton acceptor functional group is a group that can interact electrostatically with a proton or a functional group having electrons, for example, a functional group having a macrocyclic structure such as a cyclic polyether, or a functional group having a nitrogen atom with an unshared electron pair that does not contribute to π conjugation. A nitrogen atom with an unshared electron pair that does not contribute to π conjugation is, for example, a nitrogen atom having the partial structure shown in the following formula.

[0314] [Chemical formula]

[0315] Preferred partial structures of the proton acceptor functional group include, for example, crown ether, azacrown ether, primary to tertiary amines, pyridine, imidazole, and pyrazine structures.

[0316] Compound (CQ2) decomposes upon irradiation with actinic rays or radiation to generate a compound in which the proton acceptor property is reduced or lost, or changes from a proton acceptor property to an acidic property. Here, the reduction or loss of the proton acceptor property, or the change from a proton acceptor property to an acidic property is a change in the proton acceptor property caused by the addition of a proton to the proton acceptor functional group. Specifically, when a proton adduct is formed from a compound (CQ2) having a proton acceptor functional group and a proton, the equilibrium constant in the chemical equilibrium decreases. The proton acceptor property can be confirmed by measuring the pH.

[0317] The pKa of the compound generated by the decomposition of compound (CQ2) upon irradiation with actinic rays or radiation is preferably pKa < -1, more preferably -13 < pKa < -1, and even more preferably -13 < pKa < -3. The compound generated in this way may undergo intramolecular neutralization so that the pKa becomes -1 or higher.

[0318] Compound (CQ2) is preferably a compound represented by formula (c-1). R - B - X - A - W1 - N --W2-R f [C + ] (c-1)

[0319] In formula (c-1), W1 and W2 each independently represent -SO2- or -CO-. R f This represents an optionally substituted alkyl group, an optionally substituted cycloalkyl group, or an optionally substituted aryl group. A represents a single bond or a divalent linking group. X represents a single bond, -SO2-, or -CO-. B is a single bond, an oxygen atom, or -N(R x )R y - represents R x represents a hydrogen atom or an organic group. R y This represents a single bond or a divalent organic group. R represents a monovalent organic group having a proton-accepting functional group. R x R y It may bond with R to form a ring, or it may bond with R to form a ring. [C + ] represents a countercation.

[0320] It is preferable that at least one of W1 and W2 is -SO2-, and more preferably that both are -SO2-.

[0321] Rf is preferably an alkyl group which may have 1 to 6 fluorine atoms, more preferably a perfluoroalkyl group which has 1 to 6 carbon atoms, and even more preferably a perfluoroalkyl group which has 1 to 3 carbon atoms.

[0322] The divalent linking group in A is preferably a divalent linking group having 2 to 12 carbon atoms, such as an alkylene group and a phenylene group. Among these, an alkylene group having at least one fluorine atom is preferred, with 2 to 6 carbon atoms preferred, and 2 to 4 carbon atoms more preferred. The alkylene chain may also have linking groups such as oxygen atoms or sulfur atoms. The alkylene group is preferably one in which 30 to 100% of the number of hydrogen atoms are replaced with fluorine atoms, and it is more preferable that the carbon atom bonded to the Q site has a fluorine atom. Among these, the divalent linking group in A is preferably a perfluoroalkylene group, and more preferably a perfluoroethylene group, a perfluoropropylene group, or a perfluorobutylene group.

[0323] The monovalent organic group in Rx is preferably one having 2 to 30 carbon atoms, and examples include alkyl groups, cycloalkyl groups which may have an oxygen atom in the ring, aryl groups, aralkyl groups, and alkenyl groups. The alkyl group in Rx may have substituents, and is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, and may contain an oxygen atom, a sulfur atom, and / or a nitrogen atom in the alkyl chain. Examples of alkyl groups having substituents include groups in which a cycloalkyl group is substituted on a linear or branched alkyl group (for example, adamantylmethyl group, adamantylethyl group, and cyclohexylethyl group). The cycloalkyl group in Rx may have substituents, and a cycloalkyl group having 3 to 20 carbon atoms is preferred. Furthermore, the cycloalkyl group may have an oxygen atom within its ring. The aryl group in Rx may have substituents, and is preferably an aryl group having 6 to 14 carbon atoms. The aralkyl group in Rx may have substituents, and preferably an aralkyl group having 7 to 20 carbon atoms. The alkenyl group in Rx may have substituents; for example, a group having a double bond at any position of the alkyl group listed as Rx.

[0324] When B represents -N(Rx)Ry-, an alkylene group is preferred as the divalent organic group in Ry. In this case, the ring that can be formed by the bonding of Rx and Ry is, for example, a 5-8 membered ring containing a nitrogen atom, and particularly preferably a 6 membered ring. The nitrogen atom contained in the ring may be a nitrogen atom other than the nitrogen atom directly bonded to X in -N(Rx)Ry-.

[0325] When B represents -N(Rx)Ry-, it is preferable that R and Rx are bonded to each other to form a ring. Forming a ring improves stability, and thus improves the storage stability of compositions using it. The number of carbon atoms forming the ring is preferably 4 to 20, and it may be monocyclic or polycyclic, and may contain oxygen atoms, sulfur atoms, and / or nitrogen atoms. The nitrogen atoms contained in the ring may be nitrogen atoms other than the nitrogen atoms directly bonded to X in -N(Rx)Ry-.

[0326] Examples of monocyclic rings include 4-membered, 5-membered, 6-membered, 7-membered, and 8-membered rings containing a nitrogen atom. Examples of such ring structures include piperazine rings and piperidine rings. Examples of polycyclic rings include structures consisting of a combination of two or more monocyclic structures. Both monocyclic and polycyclic rings may have substituents, such as halogen atoms, hydroxyl groups, cyano groups, carboxyl groups, carbonyl groups, cycloalkyl groups (preferably with 3 to 10 carbon atoms), aryl groups (preferably with 6 to 14 carbon atoms), alkoxy groups (preferably with 1 to 10 carbon atoms), acyl groups (preferably with 2 to 15 carbon atoms), alkoxycarbonyl groups (preferably with 2 to 15 carbon atoms), or aminoacyl groups (preferably with 2 to 20 carbon atoms). These substituents may have further substituents if possible. Examples of cases where aryl groups and cycloalkyl groups have further substituents include alkyl groups (preferably with 1 to 15 carbon atoms). Examples of substituents that the aminoacyl group may further have include alkyl groups (preferably having 1 to 15 carbon atoms).

[0327] The proton-accepting functional group in R is as described above, and it is preferable that the substructure has, for example, a crown ether, a primary to tertiary amine, and a nitrogen-containing heterocycle (such as pyridine, imidazole, and pyrazine). Furthermore, as proton-accepting functional groups, functional groups having a nitrogen atom are preferred, and groups having a primary to tertiary amino group, or nitrogen-containing heterocyclic groups are more preferred. In these structures, it is preferable that all atoms adjacent to the nitrogen atom contained in the structure are carbon atoms or hydrogen atoms. In addition, it is preferable that electron-withdrawing functional groups (carbonyl groups, sulfonyl groups, cyano groups, and halogen atoms, etc.) are not directly bonded to the nitrogen atom. In a monovalent organic group (group R) containing such a proton-accepting functional group, preferred monovalent organic groups have 2 to 30 carbon atoms and include alkyl groups, cycloalkyl groups, aryl groups, aralkyl groups, and alkenyl groups, and each group may have substituents.

[0328] The alkyl, cycloalkyl, aryl, aralkyl, and alkenyl groups in R, which include a proton-accepting functional group, are the same groups as those listed as Rx, respectively.

[0329] Examples of substituents that each of the above groups may have include halogen atoms, hydroxyl groups, nitro groups, cyano groups, carboxyl groups, cycloalkyl groups (preferably having 3 to 10 carbon atoms; some may be substituted with heteroatoms or groups having heteroatoms (such as ester groups)), aryl groups (preferably having 6 to 14 carbon atoms), alkoxy groups (preferably having 1 to 10 carbon atoms), acyl groups (preferably having 2 to 20 carbon atoms), acyloxy groups (preferably having 2 to 10 carbon atoms), alkoxycarbonyl groups (preferably having 2 to 20 carbon atoms), and aminoacyl groups (preferably having 2 to 20 carbon atoms). Examples of substituents that cyclic groups such as aryl groups and cycloalkyl groups may have include alkyl groups (preferably having 1 to 20 carbon atoms). Examples of substituents that aminoacyl groups may have include 1 or 2 alkyl groups (preferably having 1 to 20 carbon atoms).

[0330] [C + For ], a sulfonium cation or an iodonium cation is preferred as the countercation. The sulfonium cation and iodonium cation can also be the cation in the compound represented by formula (ZI) and the cation in the compound represented by formula (ZII), etc.

[0331] Furthermore, low-molecular-weight compounds (hereinafter referred to as "compound (CQ3)") that have a nitrogen atom and a group that is eliminated by the action of an acid can also be used as acid diffusion control agents. The compound (CQ3) is preferably an amine derivative having a group on the nitrogen atom that is eliminated by the action of an acid. The groups that are removed by the action of an acid are preferably acetal groups, carbonate groups, carbamate groups, tertiary ester groups, tertiary hydroxyl groups, or hemiaminal ether groups, with carbamate groups or hemiaminal ether groups being more preferred. The molecular weight of compound (CQ3) is preferably 100 to 1000, more preferably 100 to 700, and even more preferably 100 to 500. Compound (CQ3) may have a carbamate group having a protecting group on the nitrogen atom. The protecting group constituting the carbamate group is preferably a group represented by the following formula (d-1).

[0332] [ka]

[0333] In equation (d-1), Each Rb independently represents 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). Rb may be linked to each other to form a ring. The alkyl, cycloalkyl, aryl, and aralkyl groups represented by Rb may each be independently substituted with functional groups such as hydroxyl, cyano, amino, pyrrolidino, piperidino, morpholino, or oxo groups, alkoxy groups, or halogen atoms. The same applies to the alkoxyalkyl groups represented by Rb.

[0334] As Rb, linear or branched alkyl groups, cycloalkyl groups, or aryl groups are preferred, and linear or branched alkyl groups, or cycloalkyl groups are more preferred. Examples of rings formed by the interconnection of two Rb molecules include alicyclic hydrocarbons, aromatic hydrocarbons, heterocyclic hydrocarbons, and their derivatives. Specific structures of the base represented by formula (d-1) include, but are not limited to, those disclosed in paragraph

[0466] of U.S. Patent Publication US2012 / 0135348A1.

[0335] Compound (CQ3) is preferably a compound having the structure represented by the following formula (6).

[0336] [ka]

[0337] In equation (6), l represents an integer between 0 and 2, and m represents an integer between 1 and 3, satisfying the condition l + m = 3. Ra represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. When l is 2, the two Ras may be the same or different, and the two Ras may be linked together with the nitrogen atom in the formula to form a heterocycle. This heterocycle may contain heteroatoms other than the nitrogen atom in the formula. Rb is synonymous with Rb in equation (d-1) above, and the preferred example is also the same. In formula (6), the alkyl group, cycloalkyl group, aryl group, and aralkyl group as Ra may each be independently substituted with a group similar to those described above, which may be a group that is substituted with an alkyl group, cycloalkyl group, aryl group, and aralkyl group as Rb.

[0338] Specific examples of the alkyl, cycloalkyl, aryl, and aralkyl groups of Ra (these groups may be substituted with the above groups) include the same groups as those specified above for Rb.

[0339] Furthermore, zwitterions can also be used as acid diffusion control agents. The zwitterionic acid diffusion control agent preferably has a carboxylate anion, and more preferably has a sulfonium cation or an iodonium cation.

[0340] Among acid diffusion control agents, those that are not basic are preferred because they exhibit superior effects compared to the present invention. Here, "not basic" refers to compounds in which the pKa of the conjugate acid is 4.5 or higher. Examples of acid diffusion control agents that do not possess basic properties include onium salts (compound (CQ1)) that are relatively weak acids to the photoacid generating components mentioned above, and low-molecular-weight compounds (compound (CQ3)) that have a nitrogen atom and a group that is eliminated by the action of an acid.

[0341] If the resist composition contains an acid diffusion control agent, the content of the acid diffusion control agent (total if there are multiple types) is preferably 0.1 to 10.0% by mass, more preferably 0.1 to 8.0% by mass, and even more preferably 0.1 to 5.0% by mass, relative to the total solid content of the composition. In the resist composition, one acid diffusion control agent may be used alone, or two or more may be used in combination.

[0342] <<(F) Ingredient (Surfactant)>> The resist composition may contain a surfactant. The inclusion of a surfactant improves adhesion and allows for the formation of patterns with fewer development defects. The surfactant is preferably a fluorine-based and / or silicone-based surfactant. Note that the fluorine-based and / or silicone-based surfactant referred to herein does not include the specific polarity conversion compound which is component (C) above. Examples of fluorinated and / or silicone-based surfactants include those disclosed in paragraphs

[0218] and

[0219] of International Publication No. 2018 / 19395.

[0343] These surfactants may be used individually or in combination of two or more types.

[0344] If the resist composition contains a surfactant, the surfactant content is preferably 0.0001 to 2% by mass, and more preferably 0.0005 to 1% by mass, relative to the total solid content of the composition.

[0345] <<(G) Ingredients (Other Additives)>> The resist composition may further contain a dissolution-inhibiting compound, a dye, a plasticizer, a photosensitizer, a light absorber, and / or a compound that promotes solubility in the developer (for example, a phenol compound with a molecular weight of 1000 or less, or an alicyclic or aliphatic compound containing a carboxylic acid group).

[0346] The resist composition may further contain a dissolution-inhibiting compound. Here, a "dissolution-inhibiting compound" is a compound with a molecular weight of 3000 or less that decomposes due to the action of an acid, thereby reducing its solubility in an organic developer.

[0347] <<Solid content of the resist composition>> The solid content in the resist composition is 10.0% by mass or more. That is, the solid content in the resist composition is 10.0% by mass or more relative to the total mass of the composition. The solid content in the resist composition is preferably 11.0% by mass or more, and more preferably 12.0% by mass or more. There is no particular upper limit, but for example, 15.0% by mass or less is preferred.

[0348] [Method for forming resist films and patterns] The pattern formation method of the present invention comprises the following steps. Step 1: A step of forming a resist film with a thickness of 500 nm or more using a resist composition. Step 2: The resist film is subjected to immersion exposure with radiation or active light with a wavelength of 200 nm or less, followed by a heat treatment. Step 3: Develop the exposed resist film with an alkaline developer to form a pattern. The following details the steps for each of the above processes.

[0349] <Step 1: Resist film formation process> Step 1 is a step of forming a resist film on a substrate using a resist composition. The resist composition is as previously described.

[0350] One method for forming a resist film on a substrate using a resist composition is to coat the resist composition onto the substrate. Furthermore, it is preferable to filter the resist composition before coating, if necessary. The pore size of the filter is preferably 0.1 μm or less, more preferably 0.05 μm or less, and even more preferably 0.03 μm or less. The filter is preferably made of polytetrafluoroethylene, polyethylene, or nylon.

[0351] The resist composition can be applied to a substrate (e.g., silicon, silicon dioxide coated) used in the manufacture of integrated circuit elements by a suitable coating method such as a spinner or coater. Spin coating using a spinner is preferred. The rotation speed when spin coating using a spinner is preferably 1000 to 3000 rpm. After applying the resist composition, the substrate may be dried to form a resist film. If necessary, various undercoats (inorganic films, organic films, anti-reflective films) may be formed beneath the resist film.

[0352] A drying treatment may be performed on the coating applied to the substrate. As for drying methods, one example is drying by heating. Heating can be carried out using means provided in a normal exposure machine and / or developing machine, or it may be carried out using a hot plate or the like. The heating temperature is preferably 80 to 150°C, more preferably 80 to 140°C, and even more preferably 80 to 130°C. The heating time is preferably 30 to 1000 seconds, more preferably 60 to 800 seconds, and even more preferably 60 to 600 seconds.

[0353] The thickness of the resist film is 500 nm or more, and more preferably 550 nm or more. As an upper limit, for example, 700 nm or less is preferred, and 600 nm or less is more preferred.

[0354] Alternatively, a topcoat may be formed on the upper layer of the resist film using a topcoat composition. Preferably, the topcoat composition does not mix with the resist film and can be uniformly applied to the upper layer of the resist film. The topcoat is not particularly limited, and conventionally known topcoats can be formed by conventionally known methods. For example, a topcoat can be formed based on the description in paragraphs

[0072] to

[0082] of Japanese Patent Application Publication No. 2014-059543. For example, it is preferable to form a topcoat containing a basic compound, such as that described in Japanese Patent Publication No. 2013-61648, on the resist film. Specific examples of basic compounds that the topcoat may contain include basic compounds that may be included in the resist composition. Furthermore, it is preferable that the top coat contains a compound comprising at least one group or bond selected from the group consisting of ether bonds, thioether bonds, hydroxyl groups, thiol groups, carbonyl bonds, and ester bonds.

[0355] <Step 2: Exposure Process> Step 2 involves immersion exposure of the resist film at a predetermined wavelength, followed by a heat treatment. The exposure step includes performing immersion exposure on the resist film formed in step 1 using radiation or active light with a wavelength of 200 nm or less, through a predetermined mask. Examples of radiation or active light with wavelengths of 200 nm or less include far-ultraviolet light with wavelengths of 1 to 200 nm, specifically the ArF excimer laser (193 nm).

[0356] In step 2, after the exposure treatment, and before being subjected to the alkaline development treatment in step 3, the exposed resist film is subjected to a heat treatment (post-exposure bake). The heat treatment accelerates the reaction in the exposed areas, resulting in better sensitivity and pattern shape. The heating temperature is preferably 80 to 150°C, more preferably 80 to 140°C, and even more preferably 80 to 130°C. The heating time is preferably 10 to 1000 seconds, more preferably 10 to 180 seconds, and even more preferably 30 to 120 seconds. The heat treatment can be carried out using the means provided in a standard exposure and / or developing machine, and may also be done using a hot plate or the like.

[0357] <Process 3: Development process> Step 3 is the process of developing the exposed resist film with an alkaline developer to form a pattern.

[0358] Examples of development methods include immersing the substrate in a tank filled with developer solution for a certain period of time (dip method), puddling the developer solution onto the substrate surface using surface tension and leaving it still for a certain period of time for development (paddle method), spraying the developer solution onto the substrate surface (spray method), and continuously dispensing the developer solution while scanning a developer solution dispensing nozzle at a constant speed onto a substrate rotating at a constant speed (dynamic dispensing method). Alternatively, after the developing process, a step may be performed to stop the development process while substituting with another solvent. There are no particular restrictions on the development time, as long as it is enough time for the resin in the unexposed areas to dissolve sufficiently, but 10 to 300 seconds is preferred, and 20 to 120 seconds is more preferred. The developer temperature is preferably 0 to 50°C, and more preferably 15 to 35°C.

[0359] For the alkaline developer, it is preferable to use an alkaline aqueous solution containing alkali. The type of alkaline aqueous solution is not particularly limited, but examples include alkaline aqueous solutions containing quaternary ammonium salts such as tetramethylammonium hydroxide, inorganic alkalis, primary amines, secondary amines, tertiary amines, alcohol amines, or cyclic amines. Among these, the alkaline developer is preferably an aqueous solution of a quaternary ammonium salt such as tetramethylammonium hydroxide (TMAH). Alkaline developers may be mixed with appropriate amounts of alcohols, surfactants, etc. The alkali concentration of alkaline developers is typically 0.1 to 20% by mass. The pH of alkaline developers is typically 10.0 to 15.0.

[0360] <Other processes> The above pattern forming method preferably includes a step of washing with a rinsing solution after step 3.

[0361] Examples of rinsing solutions used in the rinsing step after the development process using an alkaline developer include pure water. A suitable amount of surfactant may be added to the pure water. A suitable amount of surfactant may be added to the rinse solution.

[0362] The rinsing process is not particularly limited and can be performed by continuously discharging rinsing solution onto a substrate rotating at a constant speed (rotary coating method), immersing the substrate in a tank filled with rinsing solution for a certain period of time (dip method), or spraying rinsing solution onto the substrate surface (spray method). Furthermore, the pattern formation method of the present invention may include a heating step (post-bake) after the rinsing step. Post-bake removes any developer and rinsing solution remaining between and inside the patterns. Post-bake also has the effect of smoothing the resist pattern and improving the surface roughness of the pattern. Post-baking is typically performed at 40-250°C (preferably 90-200°C) for 10 seconds to 3 minutes (preferably 30 seconds to 120 seconds).

[0363] Alternatively, the formed pattern may be used as a mask to perform an etching process on the substrate. In other words, the pattern formed in step 3 may be used as a mask to process the substrate (or the underlying film and the substrate) to form a pattern on the substrate. The processing method for the substrate (or the underlying film and substrate) is not particularly limited, but a preferred method is to form a pattern on the substrate by performing dry etching on the substrate (or the underlying film and substrate) using the pattern formed in step 3 as a mask. Dry etching is preferably performed using oxygen plasma etching.

[0364] In the pattern forming method of the present invention, it is preferable that the various materials used (e.g., resist composition, solvent, developer, rinse solution, anti-reflective film forming composition, top coat forming composition, etc.) do not contain impurities such as metals. The impurity content in these materials is preferably 1 ppm by mass or less, more preferably 10 ppb by mass or less, even more preferably 100 ppt by mass or less, particularly preferably 10 ppt by mass or less, and most preferably 1 ppt by mass or less. Examples of metallic impurities include Na, K, Ca, Fe, Cu, Mg, Al, Li, Cr, Ni, Sn, Ag, As, Au, Ba, Cd, Co, Pb, Ti, V, W, and Zn.

[0365] One method for removing impurities such as metals from various materials is filtration using a filter. Details of filtration using a filter are described in paragraph

[0321] of International Publication No. 2020 / 004306.

[0366] Furthermore, methods for reducing impurities such as metals contained in various materials include, for example, selecting raw materials with low metal content as constituent materials for various materials, filtering the raw materials constituting various materials, and performing distillation under conditions that suppress contamination as much as possible, such as by lining the inside of the apparatus with Teflon®.

[0367] In addition to filter filtration, impurities may be removed using adsorbents, or a combination of filter filtration and adsorbents may be used. Known adsorbents can be used, such as inorganic adsorbents like silica gel and zeolite, and organic adsorbents like activated carbon. To reduce impurities such as metals contained in the above materials, it is necessary to prevent the introduction of metal impurities during the manufacturing process. Whether metal impurities have been sufficiently removed from the manufacturing equipment can be confirmed by measuring the content of metal components in the cleaning solution used to clean the manufacturing equipment. The content of metal components in the cleaning solution after use is preferably 100 ppt (parts per trillion) or less, more preferably 10 ppt or less, and even more preferably 1 ppt or less.

[0368] In organic processing solutions such as rinsing solutions, a conductive compound may be added to prevent malfunctions of chemical piping and various parts (filters, O-rings, tubes, etc.) due to electrostatic charging and subsequent electrostatic discharge. The conductive compound is not particularly limited, but methanol is an example. The amount added is not particularly limited, but in terms of maintaining desirable developing or rinsing characteristics, 10% by mass or less is preferred, and 5% by mass or less is more preferred. For chemical piping, various types of piping can be used, such as SUS (stainless steel), or piping coated with antistatic treated polyethylene, polypropylene, or fluororesin (polytetrafluoroethylene or perfluoroalkoxy resin, etc.). Similarly, for filters and O-rings, antistatic treated polyethylene, polypropylene, or fluororesin (polytetrafluoroethylene or perfluoroalkoxy resin, etc.) can be used.

[0369] [Manufacturing methods for electronic devices] Furthermore, the present invention relates to a method for manufacturing an electronic device, including the pattern formation method described above, and to an electronic device manufactured by this manufacturing method. The electronic device of the present invention is preferably mounted on electrical and electronic equipment (such as home appliances, office automation (OA) equipment, media-related equipment, optical equipment, and communication equipment).

[0370] [Actinic ray-sensitive or radiation-sensitive resin composition (resist composition)] The present invention also relates to photosensitive or radiation-sensitive resin compositions (resist compositions). The resist composition of the present invention, It contains the components shown in (A) to (D) below, and the solid content is 10.0% by mass or more. (A) A resin having hydrophilic groups and acid-degradable groups, with a weight-average molecular weight of 8,000 or less. (B) Photoacid generator (C) Compounds having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali. (D) Solvent

[0371] The resist composition described above is the same as the resist composition used in the pattern forming method of the present invention described above, and the preferred embodiment is also the same.

[0372] According to the above resist composition, when ArF immersion lithography is applied to a resist film with a thickness of 500 nm or more, it is possible to form a pattern with excellent defect suppression. [Examples]

[0373] The present invention will be described in more detail below based on examples. The materials, amounts used, proportions, processing content, and processing procedures shown in the following examples can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the examples shown below.

[0374] [Various ingredients] [Acid decomposable resin] The structures of the acid-degradable resins (Porymer-A to Porymer-G, Porymer-A', and Porymer-B') shown in Table 4 are described below. The weight-average molecular weight (Mw) and dispersion ("Pd" (Mw / Mn)) of the acid-degradable resin were measured by GPC (carrier: tetrahydrofuran (THF)) (in polystyrene equivalent). Furthermore, the composition ratio (mol%) of the acid-degradable resin was: 13 The measurement was performed using 1C-NMR (nuclear magnetic resonance). The acid-degradable resins listed below were all synthesized according to known synthesis methods.

[0375] [ka] JPEG0007860117000066.jpg39152JPEG0007860117000067.jpg44161JPEG0007860117000068.jpg44140

[0376] [ka]

[0377] Table 1 below shows the composition ratio (mol%), weight-average molecular weight, and degree of dispersion of Porymer-A to Porymer-G, Porymer-A', and Porymer-B'. In Table 1 below, the composition ratios (mol%) are shown in order from the repeating unit on the left side of the acid-degradable resins mentioned above.

[0378] [Table 1]

[0379] [Photoacid generator] The structures of the photoacid generators (PAG-A to PAG-P) shown in Table 4 are shown below.

[0380] [ka] JPEG0007860117000072.jpg31156JPEG0007860117000073.jpg38141

[0381] [ka] JPEG0007860117000075.jpg34160

[0382] [ka] JPEG0007860117000077.jpg29140 JPEG0007860117000078.jpg41111

[0383] Table 2 shows the structure and pKa of the acid generated by each photoacid generator during exposure.

[0384] [Table 2]

[0385] [Acid diffusion control agent] The structures of the acid diffusion control agents (Quencher-A to Quencher-G) shown in Table 4 are shown below. In the following, Quencher-A and Quencher-D to Quencher-F are acid diffusion control agents that do not possess basic properties.

[0386] [ka] JPEG0007860117000081.jpg38124 JPEG0007860117000082.jpg4767

[0387] [Polarity conversion compounds] The structures of the polarity-converting compounds (Surfactant-A to D, Surfactant-A', Surfactant-B') shown in Table 4 are shown below. Note that the repeating unit at the left end of Surfactant-A corresponds to the repeating unit having an alkali-decomposable group and also corresponds to the repeating unit represented by the above formula (III). Further, the repeating unit at the right end of Surfactant-B corresponds to the repeating unit having an acid-decomposable group and also corresponds to the repeating unit represented by the above formula (II). Further, the repeating unit at the right end of Surfactant-C corresponds to the repeating unit having an acid-decomposable group and also corresponds to the repeating unit represented by the above formula (II). Further, the repeating unit at the right end of Surfactant-D corresponds to the repeating unit having an acid-decomposable group and also corresponds to the repeating unit represented by the above formula (II).

[0388] [Chemical formula]

[0389] Surfactant-C [Chemical formula]

[0390] Surfactant-D [Chemical formula]

[0391] Table 3 below shows the composition ratios (mol %), weight average molecular weights, and dispersities of Surfactant-A to D and Surfactant-A'. Note that in Table 3 below, the composition ratios (mol %) are shown in order from the repeating unit on the left side of the above-mentioned polarity-converted compound (resin).

[0392] [Table 3]

[0393] <Water contact angle of Surfactant-A> When a film (single film) made of Surfactant-A is brought into contact with the alkaline developer used in Step 3, the difference between the water contact angle of the surface of the film (single film) made of Surfactant-A that is in contact with the alkaline developer and the water contact angle of the surface of the film (single film) made of Surfactant-A after being brought into contact with the alkaline developer was confirmed to be 10° or more. Here, Step 3 corresponds to the step of "developing the resist film after post-exposure baking for 30 seconds with an aqueous solution of tetramethylammonium hydroxide (TMAH) (2.38 mass%) as the developer" in <Pattern Formation (1): Formation of a Positive Pattern by ArF-wet Exposure> of [ArF Exposure Pattern Formation and Evaluation] in the latter stage.

[0394] The specific procedure for measuring the contact angle is as follows. Surfactant-A was dissolved in a solvent of PGMEA / PGME = 80 / 20 (mass%) to a concentration of 10 mass% to prepare a Surfactant composition. Next, the prepared Surfactant composition was applied onto a silicon wafer (8 inches), baked at 120°C for 60 seconds, and a Surfactant single film with a film thickness of 500 nm was formed. The contact angle of the water droplet was measured using a contact angle measuring device (manufactured by Kyowa Interface Science Co., Ltd.). A liquid droplet size of 30 μL was measured as the contact angle. The measurement environment was a temperature of 23°C and a relative humidity of 45%. The wafer used for the measurement was developed for 30 seconds with an aqueous solution of tetramethylammonium hydroxide (TMAH) (2.38 mass%) as the developer using a spin coater "ACT-8" manufactured by Tokyo Electron Limited, and then rinsed with pure water for 30 seconds. After that, it was spin-dried. Then, the contact angle was measured in the same manner as the above procedure at a location different from the measurement point in the contact angle measurement before the alkaline development treatment (in other words, changing the measurement point), and the difference in the contact angle was obtained.

[0395] <Properties of Surfactant-B> When the film (single film) made of Surfactant-B was exposed over the entire surface under the same exposure conditions as in Step 2 and heat treatment was carried out, it was confirmed that the difference between the water contact angle of the surface of the film made of Surfactant-B before the entire surface exposure and the water contact angle of the surface of the film made of Surfactant-B after the above heat treatment was 10° or more. The specific procedure is as follows. Note that Step 2 corresponds to the step of "performing pattern exposure on the resist film under predetermined conditions and baking the resist film after exposure at 120°C for 60 seconds" in <Pattern Formation (1): Formation of Positive Pattern by ArF-wet Exposure (Examples and Comparative Examples)> of [ArF Exposure Pattern Formation and Evaluation] in the latter stage.

[0396] The specific procedure for measuring the contact angle is as follows. Surfactant-B was dissolved in a solvent of PGMEA / PGME = 80 / 20 (mass%) to a concentration of 10 mass% to prepare a Surfactant composition. Next, the prepared Surfactant composition was applied onto a silicon wafer (8 inches) and baked at 120°C for 60 seconds to form a Surfactant single film with a film thickness of 500 nm. For the obtained single film, the contact angle of the water droplet was measured using a contact angle measuring device (manufactured by Kyowa Interface Science Co., Ltd.). The droplet size was 30 μL and was measured as the contact angle. The measurement environment was a temperature of 23°C and a relative humidity of 45%. Next, the entire surface of the above single film was exposed using an ArF excimer laser scanner (manufactured by ASML; PAS5500 / 1500, NA0.75, Conventional, Sigma 0.500). The immersion liquid used was ultrapure water. Then, the single film after the entire surface exposure was baked at 120°C for 60 seconds. Thereafter, contact angle measurement was performed in the same manner as the above procedure at a location different from the measurement point in the contact angle measurement before the exposure and heat treatment (in other words, the measurement point was changed), and the difference in the contact angle was determined.

[0397] <Properties of Surfactant-C> When the water contact angle of Surfactant-C was measured by the method shown in <Properties of Surfactant-B> above, it was confirmed that the difference between the water contact angle of the surface of the film made of Surfactant-C before full exposure and the water contact angle of the surface of the film made of Surfactant-C after heat treatment was 10° or more.

[0398] <Properties of Surfactant-D> When the water contact angle of Surfactant-D was measured by the method shown in <Properties of Surfactant-B> above, it was confirmed that the difference between the water contact angle of the surface of the film made of Surfactant-D before full exposure and the water contact angle of the surface of the film made of Surfactant-D after heat treatment was 10° or more.

[0399] <Properties of Surfactant-A’> Surfactant-A’ corresponds to a compound that does not have a group that generates a polar group by the action of an acid or a group that generates a polar group by the action of an alkali. When the water contact angle before and after alkali development of Surfactant-A’ was confirmed in the same manner as Surfactant-A, the difference was less than 10°. When the water contact angle before and after heat treatment of Surfactant-A’ was confirmed in the same manner as Surfactant-B, the difference was less than 10°.

[0400] <Properties of Surfactant-B’> Surfactant-B’ corresponds to a compound that does not have a group that generates a polar group by the action of an acid or a group that generates a polar group by the action of an alkali. When the water contact angle before and after alkali development of Surfactant-B’ was confirmed in the same manner as Surfactant-A, the difference was less than 10°. When the water contact angle before and after heat treatment of Surfactant-B’ was confirmed in the same manner as Surfactant-B, the difference was less than 10°.

[0401] 〔solvent〕 The abbreviations for the solvents shown in Table 4 are as follows: "PGMEA": Propylene glycol monomethyl ether acetate "PGME": Propylene glycol monomethyl ether "GBL": γ-butyrolactone

[0402] [Preparation and pattern formation of resist compositions for ArF exposure] [Preparation of resist composition for ArF exposure] The various components shown in Table 4 were mixed to obtain a solution in the amounts and solid content concentration (mass%) shown in Table 4. The resulting mixture was filtered through UPE (ultra high molecular weight polyethylene) with a pore size of 0.1 μm, Nylon with a pore size of 0.02 μm, and a UPE filter with a pore size of 0.01 μm. The resulting photosensitive or radiation-sensitive resin composition (resist composition) was used in the examples and comparative examples. In the resist compositions of the examples and comparative examples, "solids" refers to all components other than the solvent. Furthermore, the "content (mass %)" for each component other than the solvent shown in Table 4 refers to the content ratio relative to the total solids. The "content ratio" in the "Component (D) / Solvent" column shown in Table 4 refers to the content ratio (mass %) of each solvent relative to the total solvent. In addition, "solids concentration" refers to the solids content (mass %) relative to the total mass of the resist composition.

[0403] [ArF exposure pattern formation and evaluation] <Pattern Formation (1): Formation of Positive Patterns by ArF-wet Exposure (Examples and Comparative Examples)> Using the ACT-12 spin coater manufactured by Tokyo Electron Limited, the organic anti-reflective coating composition ARC29SR (manufactured by Brewer Science) was applied to a silicon wafer (12 inches), and the mixture was baked at 205°C for 60 seconds to form an anti-reflective coating with a thickness of 98 nm. Next, each resist composition was applied to the obtained anti-reflective film using the same apparatus and baked at 120°C for 60 seconds to form a resist film with a thickness corresponding to each resist composition (film thickness: see Table 4). Then, the obtained resist film was pattern-exposed using an ArF excimer laser immersion scanner (ASML; XT1700i, NA 1.20, C-Quad, outer sigma 0.900, inner sigma 0.812, XY deflection) through a 6% halftone mask with a pitch of 140 nm and a spacing of 70 nm. Ultrapure water was used as the immersion solution. After exposure, the resist film was baked at 120°C for 60 seconds, then developed with an aqueous solution of tetramethylammonium hydroxide (TMAH) (2.38% by mass) for 30 seconds, followed by rinsing with pure water for 30 seconds. This was then spin-dried to obtain a line-and-space pattern (LS pattern) with a pitch of 140 nm and a spacing of 70 nm.

[0404] [evaluation] [Defect Assessment] Using the AMAT Uvision5 defect inspection system, the defect distribution of patterns on a 12-inch silicon wafer was detected, and the number of defects (in units of pieces) on the wafer was calculated. A smaller value indicates better performance. Note that the number of defects in the wafer mentioned above (unit: pieces) refers to the number of defects per 12-inch silicon wafer.

[0405] Table 4 is shown below.

[0406] [Table 4]

[0407] [Table 5]

[0408] As shown in Table 4 above, it has been confirmed that the pattern formation method of the present invention can form patterns with excellent defect suppression properties. Furthermore, it was confirmed that using the compound represented by formula (ZI-3) as the photoacid generator resulted in superior suppression of defects in the formed pattern (see results in Examples 9-15, 24-26, etc.). Furthermore, it was confirmed that when the acid-degradable resin has two or more repeating units with hydrophilic groups, the defect suppression of the formed pattern is even better (see results in Examples 27-29, etc.). Furthermore, it was confirmed that when the number of carbon atoms in the leaving group of the acid-degradable group in the acid-degradable resin is 8 or more, the defect suppression of the formed pattern is superior (see the results of Examples 27 and 29, etc.). Furthermore, it was confirmed that when the solvent contains propylene glycol monoalkyl ether carboxylate, propylene glycol monoalkyl ether, and lactone, the defect suppression of the formed pattern is superior (see results in Example 30, etc.). Furthermore, it was confirmed that when at least one of the photoacid generator, acid diffusion control agent, and polarity conversion compound is used in combination in two or more forms, the ability to suppress defects in the formed pattern is even better (see the results of Examples 32-34, etc.).

[0409] On the other hand, the resist compositions in the comparative examples exhibited insufficient performance in these areas.

[0410] Furthermore, pattern formation was performed using the same method as in Comparative Example 1, except that the resist film thickness was set to 100 nm (solid content concentration of resist composition: 4% by mass), and the same defect evaluation was carried out. Compared to the pattern formation method in Comparative Example 1, the number of defects in the formed pattern was reduced, but the desired defect suppression performance was not achieved.

[0411] Furthermore, pattern formation was performed using the same method as in Comparative Example 1, except that the pattern was formed by <Pattern Formation (2): Formation of Positive Pattern by ArF-dry Exposure> shown below, and the same defect evaluation was carried out. Compared to the pattern formation method of Comparative Example 1, the number of defects in the formed pattern was reduced, but the desired defect suppression performance was not achieved.

[0412] <Pattern Formation (2): Formation of Positive Patterns by ArF-dry Exposure> Using the "ACT-12" spin coater manufactured by Tokyo Electron Limited, the organic anti-reflective coating composition ARC29A (manufactured by Brewer Science) was applied to a silicon wafer (12 inches), and the mixture was baked at 205°C for 60 seconds to form an anti-reflective coating with a thickness of 82 nm. Next, the resist composition was applied to the obtained anti-reflective film using the same apparatus and baked at 120°C for 60 seconds to form a resist film with a thickness corresponding to the resist composition (film thickness: see Table 4). Then, the obtained resist film was pattern-exposed using an ASML ArF scanner PAS5500 / 1100 (NA 0.75, Annular, Outer Sigma 0.85, Inner Sigma 0.60) through a 6% halftone mask with a pitch of 200 nm and a spacing of 100 nm. After exposure, the resist film was baked at 120°C for 60 seconds, then developed with an aqueous solution of tetramethylammonium hydroxide (TMAH) (2.38% by mass) for 30 seconds, followed by rinsing with pure water for 30 seconds. This was then spin-dried to obtain a line-and-space pattern (LS pattern) with a pitch of 200 nm and a spacing of 100 nm.

Claims

1. Step 1: Forming a resist film with a thickness of 500 nm or more using a photosensitive or radiation-sensitive resin composition. Step 2 involves immersion exposure of the resist film with radiation or active light with a wavelength of 200 nm or less, followed by a heat treatment. A pattern forming method comprising step 3 of developing the exposed resist film with an alkaline developer to form a pattern, The aforementioned photosensitive or radiation-sensitive resin composition contains the components shown in (A) to (D) below, (A) A resin having hydrophilic groups and acid-degradable groups, with a weight-average molecular weight of 8,000 or less. (B) Photoacid generator (C) Compounds having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali. (D) Solvent and, The solid content in the aforementioned photosensitive or radiation-sensitive resin composition is 10.0% by mass or more. A pattern-forming method wherein the photoacid generator shown in (B) above contains a compound represented by the following formula (ZI-3). 【Chemistry 1】 In the above formula (ZI-3), R １ R represents an alkyl group, cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, or alkenyl group. ２ and R ３ Each of these independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, or an aryl group. １ and R ２ They may be bonded to each other to form a ring. Also, R ２ and R ３ These elements may be joined to each other to form a ring. Also, R Ｘ and R ｙ each independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, or an alkoxycarbonylcycloalkyl group. Here, R Ｘ and R ｙ may be bonded to each other to form a ring, and further, this ring may contain an oxygen atom, a nitrogen atom, a sulfur atom, a ketone group, an ether bond, an ester bond, or an amide bond. Z － This represents an anion.

2. The pattern forming method according to claim 1, wherein the compound shown in (C) above includes a repeating unit X having a group that generates a polar group upon the action of an acid or a group that generates a polar group upon the action of an alkali.

3. The pattern forming method according to claim 2, wherein the repeating unit X is a repeating unit represented by the following formula (II) or the following formula (III). 【Chemistry 2】 In formula (II), A represents a carbon atom or a silicon atom. １１ R represents a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. １２ , R １３ , and R １４ Each of these independently represents a linear, branched, or cyclic alkyl group, which may be substituted. １２ and R １３ These elements may be joined to each other to form a ring. 【Transformation 3】 In formula (III), L represents a divalent organic group. ２１ R represents a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. ２２ represents a monovalent organic group. However, the repeating unit represented by formula (III) includes structural sites that generate polar groups through the action of fluorine atoms and alkalis.

4. The pattern forming method according to any one of claims 1 to 3, wherein the compound shown in (C) satisfies either requirement 1 or requirement 2 below. Requirement 1: If the compound has a group that generates a polar group upon the action of an acid, when a film made of the compound is subjected to full-surface exposure under the same exposure conditions as in step 2 and then heat-treated, the difference between the water contact angle of the surface of the film made of the compound before full-surface exposure and the water contact angle of the surface of the film made of the compound after the heat-treated treatment must be 10° or more. Requirement 2: If the compound has a group that generates a polar group upon the action of alkali, when the film made of the compound is brought into contact with the alkaline developer used in step 3, the difference between the water contact angle of the surface of the film made of the compound before contact with the alkaline developer and the water contact angle of the surface of the film made of the compound after contact with the alkaline developer must be 10° or more.

5. The pattern forming method according to any one of claims 1 to 3, wherein the resin shown in (A) above comprises two or more repeating units having hydrophilic groups, and at least two of the two or more repeating units have hydrophilic groups that are different from each other.

6. The pattern forming method according to any one of claims 1 to 3, wherein the resin shown in (A) above comprises one or more repeating units having a carboxyl group and one or more repeating units having a hydroxyl group.

7. The pattern forming method according to any one of claims 1 to 3, wherein the acid-degradable group of the resin shown in (A) above has a structure in which a polar group is protected by a leaving group that is removed by the action of an acid, and the number of carbon atoms of the leaving group is 8 or more.

8. The pattern forming method according to any one of claims 1 to 3, wherein the activated photosensitive or radiation-sensitive resin composition further comprises a compound shown in (E) below. (E) Acid diffusion control agents that do not have basic properties

9. The pattern forming method according to any one of claims 1 to 3, wherein the resin shown in (A) above does not contain fluorine atoms and silicon atoms.

10. The pattern forming method according to any one of claims 1 to 3, wherein the content of the component indicated in (C) above is 10.0% by mass or less with respect to the total solid content of the composition.

11. A method for manufacturing an electronic device, comprising a pattern forming method according to any one of claims 1 to 3.

12. It contains the components shown in (A) to (D) below, and the solid content is 10.0% by mass or more. (A) A resin having hydrophilic groups and acid-degradable groups, with a weight-average molecular weight of 8,000 or less. (B) Photoacid generator (C) Compounds having a fluorine atom or a silicon atom and a group that generates a polar group upon the action of an acid or an alkali. (D) Solvent, A photosensitive or radiation-sensitive resin composition wherein the photoacid generator described in (B) contains a compound represented by the following formula (ZI-3). 【Chemistry 4】 In the above formula (ZI-3), R １ R represents an alkyl group, cycloalkyl group, alkoxy group, cycloalkoxy group, aryl group, or alkenyl group. ２ and R ３ Each of these independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, or an aryl group. １ and R ２ They may be bonded to each other to form a ring. Also, R ２ and R ３ These elements may be joined to each other to form a ring. Also, R Ｘ and R ｙ Each of these independently represents an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, or an alkoxycarbonylcycloalkyl group. Ｘ and R ｙ These elements may be bonded to each other to form a ring, and this ring may further contain an oxygen atom, a nitrogen atom, a sulfur atom, a ketone group, an ether bond, an ester bond, or an amide bond. Z － This represents an anion.

13. The photosensitive or radiation-sensitive resin composition according to claim 12, wherein the compound shown in (C) above includes a repeating unit X having a group that generates a polar group upon the action of an acid or a group that generates a polar group upon the action of an alkali.

14. The photosensitive or radiation-sensitive resin composition according to claim 13, wherein the repeating unit X is a repeating unit represented by the following formula (II) or the following formula (III). 【Transformation 5】 In formula (II), A represents a carbon atom or a silicon atom. １１ R represents a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. １２ , R １３ , and R １４ Each of these independently represents a linear, branched, or cyclic alkyl group, which may be substituted. １２ and R １３ These elements may be joined to each other to form a ring. 【Transformation 6】 In formula (III), L represents a divalent organic group. ２１ R represents a hydrogen atom, a methyl group, a fluorine atom, or a trifluoromethyl group. ２２ represents a monovalent organic group. However, the repeating unit represented by formula (III) includes structural sites that generate polar groups through the action of fluorine atoms and alkalis.

15. The photosensitive or radiation-sensitive resin composition according to any one of claims 12 to 14, wherein the compound shown in (C) satisfies either requirement 1 or requirement 2 below. Requirement 1: If the compound has a group that generates a polar group upon the action of an acid, when a film made of the compound is subjected to full-surface exposure under the same exposure conditions as in step 2 and then heat-treated, the difference between the water contact angle of the surface of the film made of the compound before full-surface exposure and the water contact angle of the surface of the film made of the compound after the heat-treated treatment must be 10° or more. Requirement 2: If the compound has a group that generates a polar group upon the action of alkali, when the film made of the compound is brought into contact with the alkaline developer used in step 3, the difference between the water contact angle of the surface of the film made of the compound before contact with the alkaline developer and the water contact angle of the surface of the film made of the compound after contact with the alkaline developer must be 10° or more.

16. The photosensitive or radiation-sensitive resin composition according to any one of claims 12 to 14, wherein the resin shown in (A) above comprises two or more repeating units having hydrophilic groups, and at least two of the two or more repeating units have hydrophilic groups that are different from each other.

17. The resin described in (A) above comprises one or more repeating units having a carboxyl group and one or more repeating units having a hydroxyl group, according to any one of claims 12 to 14, a photosensitive or radiation-sensitive resin composition.

18. The acid-degradable group of the resin shown in (A) above has a structure in which a polar group is protected by a leaving group that is removed by the action of an acid, and the number of carbon atoms of the leaving group is 8 or more, according to any one of claims 12 to 14.

19. Furthermore, the photosensitive or radiation-sensitive resin composition according to any one of claims 12 to 14, further comprising the compound shown in (E) below. (E) Acid diffusion control agents that do not have basic properties

20. The resin referred to in (A) above is a photosensitive or radiation-sensitive resin composition according to any one of claims 12 to 14, wherein the resin does not contain fluorine atoms or silicon atoms.

21. The photosensitive or radiation-sensitive resin composition according to any one of claims 12 to 14, wherein the content of the component indicated in (C) above is 10.0% by mass or less with respect to the total solid content of the composition.

22. A resist film formed using the photosensitive or radiation-sensitive resin composition according to any one of claims 12 to 14.

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