Pattern forming methods and electronic component manufacturing methods

Abstract

This invention provides a pattern forming method and a method for manufacturing electronic components that suppresses long-period undulations in the formed pattern. The pattern forming method includes: step 1, fabricating a laminate having a substrate, a resist layer, an intermediate layer, and a conductive layer sequentially; step 2, irradiating the laminate with an electron beam in a patterned manner; and step 3, performing a development process on the laminate irradiated with the electron beam to form a pattern, wherein the resist layer has a film thickness of 150 nm or less.

Description

[Technical Field]

[0001] This invention relates to a pattern forming method and a method for manufacturing electronic components. [Previous Technology]

[0002] In recent years, electron beam lithography, as a higher-resolution exposure technology, has attracted much attention. Patent Document 1 discloses a method for forming patterns using a laminate having a resist layer, an intermediate layer, and a conductive layer sequentially, for the purpose of suppressing the reaction between the resist layer and the conductive layer. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2010-153641 [Summary of the Invention]

[0004] [Problem to be Solved by the Invention] On the other hand, with the further miniaturization of patterns, in recent years, there has been a demand to suppress long-period undulations in the length direction of the formed pattern. These long-period undulations refer to the phenomenon where the position of the line center changes along the length direction of the pattern while the width of the pattern remains approximately constant.

[0005] The inventors have found that when forming a pattern using the laminate specifically described in Patent Document 1, the long-period fluctuations occur and need to be improved.

[0006] In view of the aforementioned circumstances, the present invention aims to provide a pattern forming method that suppresses long-period undulations in the formed pattern. Furthermore, the present invention also aims to provide a method for manufacturing an electronic component. [Means for Solving the Problems]

[0007] The inventors have discovered that the aforementioned problem can be solved by the following structure.

[0008] (1) A pattern forming method, comprising: step 1, fabricating a laminate having a substrate, a resist layer, an intermediate layer and a conductive layer sequentially; step 2, irradiating the laminate with an electron beam in a patterned manner; and step 3, performing a development treatment on the laminate irradiated with the electron beam to form a pattern, wherein the thickness of the resist layer is 150 nm or less. (2) The pattern forming method of (1), wherein step 1 comprises: step 1A, coating a resist layer forming composition on a substrate to form a resist layer; step 1B, coating an intermediate layer forming composition on the resist layer to form an intermediate layer; and step 1C, coating a conductive layer forming composition on the intermediate layer to form a conductive layer. (3) The pattern forming method of (1) or (2), wherein the resist layer comprises a resin whose solubility relative to a developing solution changes by the action of an acid, satisfying at least one of requirements 1 and 2 described below. (4) The pattern forming method as described in (3), wherein, if requirement 1 is satisfied, the content of the compound is 10% by mass or more relative to the total mass of the resist layer, and if requirement 2 is satisfied, the content of the repeating unit is 10% by mass or more relative to the total mass of the resist layer. (5) The pattern forming method as described in (3) or (4), wherein the pKa of the acid produced by the compound that generates acid by irradiation with an electron beam is -1.00 or less. (6) The pattern forming method as described in any one of (3) to (5), wherein the size of the acid produced by the compound that generates acid by irradiation with an electron beam is 240 Å3 or more. (7) The pattern forming method as described in any one of (3) to (6), wherein the compound that generates acid by irradiation with an electron beam is one or more compounds selected from compounds (I) and (II) described later. (8) The pattern forming method as described in any one of (3) to (7), wherein the resin contains repeating units having acid groups. (9) The pattern forming method as described in (8), wherein the acid group is selected from the group consisting of phenolic hydroxyl groups and fluorinated alcohol groups. (10) The pattern forming method as described in any one of (3) to (9), wherein the resin comprises a repeating unit having a group that decomposes to produce a carboxyl group by the action of an acid. (11) The pattern forming method as described in any one of (3) to (9), wherein the resin comprises a repeating unit having a group that decomposes to produce a phenolic hydroxyl group by the action of an acid. (12) The pattern forming method as described in any one of (3) to (11), wherein the resin comprises a repeating unit having at least one group selected from the group consisting of lactone groups, sulopentalide groups, and carbonate groups. (13) The pattern forming method as described in any one of (1) to (12), wherein the resist layer comprises an alkaline compound whose alkalinity is reduced or disappears by electron beam irradiation.(14) The pattern forming method of (13), wherein the alkaline compound comprises an onium salt compound that generates an acid by electron beam irradiation, and the acid generated from the onium salt is a weak acid compared to the acid generated from the compound that generates an acid by electron beam irradiation. (15) The pattern forming method of any one of (1) to (14), wherein the intermediate layer is soluble in the developer used in the developing process. (16) The pattern forming method of any one of (1) to (15), wherein the intermediate layer is a layer formed using an intermediate layer forming composition, the intermediate layer forming composition comprising a resin soluble in the developer used in the developing process, and a solvent that substantially does not dissolve the resist layer. (17) The pattern forming method of (16), wherein the solvent that substantially does not dissolve the resist layer is selected from the group consisting of monohydric alcohols having 4 to 10 carbon atoms, ethers having 6 to 14 carbon atoms, and hydrocarbons having 8 to 14 carbon atoms. (18) A pattern forming method as described in (16) or (17), wherein the resin soluble in the developing solution used in the developing process comprises a repeating unit having at least one group selected from the group consisting of carboxyl, phenolic hydroxyl, fluorinated alcohol, sulfonic acid, and sulfonamide. (19) A method for manufacturing an electronic component, comprising a pattern forming method as described in any one of (1) to (18). [Effects of the Invention].

[0009] According to the present invention, a pattern forming method is provided in which long-period undulations of the formed pattern are suppressed. Additionally, according to the present invention, a method for manufacturing an electronic component is also provided.

Implementation Method

[0011] Hereinafter, the present invention will be described in detail. The description of the constituent elements described below is sometimes based on representative embodiments of the present invention, but the present invention is not limited to the said embodiments. Regarding the description of "group" (atomic group) in this specification, as long as it does not violate the spirit of the present invention, the description of "unsubstituted" and "unsubstituted" also includes groups without substituents and groups with substituents. For example, the term "alkyl" includes not only alkyl groups without substituents (unsubstituted alkyl groups) but also alkyl groups with substituents (substituted alkyl groups). In addition, "organic group" in this specification refers to a group containing at least one carbon atom. Unless otherwise specified, substituents are preferably monovalent substituents. In this specification, the term "~" is used to mean the lower limit and upper limit of the value described before and after it. The bonding direction of divalent groups described in this specification is not limited unless otherwise specified. For example, in the case where Y in the compound represented by the formula "XYZ" is -COO-, Y can be -CO-O- or -O-CO-. In addition, the compound may be "X-CO-OZ" or "XO-CO-Z".

[0012] 1 Å is 1×10-10m.

[0013] In this specification, (meth)acrylate refers to acrylate and methacrylate, and (meth)acrylic acid refers to acrylic acid and methacrylic acid. In this specification, the weight average molecular weight (Mw), number average molecular weight (Mn), and dispersion (also known as molecular weight distribution) (Mw / Mn) of the resin are defined as polystyrene conversion values ​​obtained by GPC determination using a gel permeation chromatography (GPC) apparatus (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: refractive index detector)

[0014] The acid dissociation constant (pKa) referred to in this specification refers to the pKa in aqueous solution, specifically obtained by calculation using the following software package 1, based on a database of Hammett substituent constants and known literature values. Software package 1: Advanced Chemistry Development (ACD / Labs) Solaris System Software V8.14 (1994-2007 ACD / Labs).

[0015] On the other hand, pKa is also determined by molecular orbital calculations. A specific method for this is the calculation of the H+ dissociation free energy in aqueous solution based on thermodynamic cycles. Regarding the calculation of the H+ dissociation free energy, density functional theory (DFT) can be used, for example, and various other methods have been reported in the literature, and this is not a limitation. Furthermore, several software programs are available for performing DFT, such as Gaussian16.

[0016] As described herein, pKa refers to the value obtained by using software package 1 to calculate a database based on Hammett substituent constants and known literature values. In cases where pKa cannot be calculated using this method, a value obtained using density functional theory (DFT) and Gaussian 16 is employed. Furthermore, as described herein, pKa refers to "pKa in aqueous solution." In cases where pKa in aqueous solution cannot be calculated, "pKa in dimethyl sulfoxide (DMSO) solution" is used.

[0017] In this specification, halogen atoms include, for example, fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. In this specification, "solid component" refers to all components other than the solvent. Furthermore, even if the solid component is in liquid form, it is calculated as a solid component.

[0018] As a characteristic of the pattern forming method of the present invention, the following aspects can be listed: the thickness of the resist layer in the laminate having a substrate, a resist layer, an intermediate layer and a conductive layer in sequence is 150 nm or less. The inventors have discovered that by making the resist layer thinner than before, the long-period undulations of the formed pattern are suppressed.

[0019] The pattern forming method of the present invention includes the following steps 1 to 3. Step 1: A step of forming a laminate having a substrate, a resist layer, an intermediate layer and a conductive layer in sequence. Step 2: A step of irradiating the laminate with an electron beam in a patterned manner. Step 3: A step of performing a development process on the laminate irradiated with the electron beam to form a pattern. Hereinafter, the procedure of each step will be explained.

[0020] <Step 1> Step 1 is the step of fabricating a laminate having a substrate, a resist layer, an intermediate layer and a conductive layer in sequence. The substrate, resist layer, intermediate layer and conductive layer will be described in detail later.

[0021] The method for manufacturing the laminate is not particularly limited. For example, methods such as sequentially coating components for forming each layer onto a substrate to form each layer, and methods such as sequentially transferring a separately fabricated resist layer, intermediate layer, and conductive layer onto a substrate are included. In terms of superior productivity, step 1 preferably includes: step 1A, coating a resist layer forming component onto the substrate to form a resist layer; step 1B, coating an intermediate layer forming component onto the resist layer to form an intermediate layer; and step 1C, coating a conductive layer forming component onto the intermediate layer to form a conductive layer. Steps 1A to 1C will be described in detail below.

[0022] Step 1A is a step of forming a resist layer by coating a resist layer forming composition onto a substrate. The resist layer forming composition will be described in detail later. There are no particular limitations on the method of coating the resist layer forming composition onto the substrate; for example, coating methods using a spin coater or a coating machine can be listed. Among these, spin coating using a spin coater is preferred. The rotation speed when performing spin coating using a spin coater is preferably 1000 rpm to 3000 rpm.

[0023] A drying process may also be performed after the resist layer is coated, if necessary. Methods for drying include, for example, drying by heating. Heating can be performed using mechanisms included in a conventional exposure machine and / or developing machine, or using a heating plate, etc. The heating temperature is preferably 80°C to 150°C, more preferably 80°C to 140°C. The heating time is preferably 30 seconds to 1000 seconds, more preferably 60 seconds to 800 seconds.

[0024] Preferably, the resist layer is insoluble in the solvent contained in the intermediate layer forming composition used in step 1B. Insolubility means that when a 100 nm thick resist layer is immersed in the solvent (30 ml) contained in the intermediate layer forming composition for 30 seconds, the reduction in the resist layer's film thickness is 3.0 nm or less. Preferably, the reduction in the resist layer's film thickness is 1.5 nm or less.

[0025] The thickness of the resist layer is 150 nm or less. Specifically, for aspects where long-period undulations of the formed pattern are further suppressed (hereinafter also referred to as "aspects of the invention with better effects"), it is preferably 120 nm or less, more preferably 90 nm or less. There is no particular limitation on the lower limit, but it is preferably 20 nm or more, more preferably 30 nm or more. As a method for measuring the thickness of the resist layer, the following method can be used: measuring the thickness of the resist layer at any 10 points, arithmetically averaging the obtained thicknesses at the 10 points, and setting the obtained average value as the thickness of the resist layer. That is, the thickness of the resist layer is the average thickness.

[0026] Step 1B is a step of forming an intermediate layer by coating an intermediate layer composition onto the resist layer. The intermediate layer composition will be described in detail later. There are no particular limitations on the method of coating the intermediate layer composition onto the resist layer; methods for coating the resist layer composition onto a substrate are also listed. A drying process may also be performed after coating the intermediate layer composition, as needed. Methods for drying that can be performed after coating the resist layer composition are also listed.

[0027] Preferably, the intermediate layer is insoluble in the solvent contained in the composition for forming the conductive layer used in step 1C. Insolubility means that when a 100 nm thick intermediate layer is immersed in the solvent (30 ml) contained in the composition for forming the conductive layer for 30 seconds, the film reduction of the intermediate layer is 3.0 nm or less. Preferably, the film reduction of the intermediate layer is 1.5 nm or less.

[0028] The intermediate layer is preferably soluble in the developing solution used in the developing process performed in step 3 described later. Solubility means that when a 100 nm thick intermediate layer is immersed in the developing solution (30 ml) used in the developing process for 30 seconds, the film reduction of the intermediate layer is 98 nm or more. Preferably, the film reduction of the intermediate layer is 100 nm.

[0029] The thickness of the intermediate layer is not particularly limited, but for aspects that are more advantageous to the present invention, it is preferably 20 nm to 100 nm, and more preferably 40 nm to 80 nm. As a method for measuring the thickness of the intermediate layer, the following method can be used: measure the thickness of the intermediate layer at any 10 points, perform an arithmetic average of the obtained thicknesses at the 10 points, and set the average value as the thickness of the intermediate layer. That is, the thickness of the intermediate layer is the average thickness.

[0030] Step 1C is a step of forming a conductive layer by coating a conductive layer forming composition onto an intermediate layer. The conductive layer forming composition will be described in detail later. There are no particular limitations on the method of coating the conductive layer forming composition onto the intermediate layer; methods for coating the resist layer forming composition onto a substrate are also included. A drying process may also be performed after coating the conductive layer forming composition, as needed. Methods for drying that can be performed after coating the resist layer forming composition are also included.

[0031] Preferably, the conductive layer is soluble in the developing solution used in the developing process performed in step 3 described later. Solubility means that when a 100 nm thick conductive layer is immersed in the developing solution (30 ml) used in the developing process for 30 seconds, the reduction in the thickness of the conductive layer is 98 nm or more. Preferably, the reduction in the thickness of the conductive layer is 100 nm.

[0032] The thickness of the conductive layer is not particularly limited, but for aspects that are more advantageous to the present invention, it is preferably 10 nm to 60 nm, and more preferably 20 nm to 40 nm. As a method for measuring the thickness of the conductive layer, the following method can be used: measure the thickness of the conductive layer at any 10 points, perform an arithmetic average of the obtained thicknesses at the 10 points, and set the obtained average value as the thickness of the conductive layer. That is, the thickness of the conductive layer is the average thickness.

[0033] <Step 2> Step 2 is the step of irradiating the laminate with an electron beam in a pattern. The areas in the laminate irradiated with the electron beam are patterned, for example, irradiated with the electron beam in a line pattern. Furthermore, the electron beam usually irradiates the laminate from the conductive layer side.

[0034] Preferably, baking (heating) is performed after electron beam irradiation and before step 3. Baking in the electron beam irradiated area promotes the reaction, resulting in better sensitivity and pattern shape. The heating temperature is preferably 80°C to 150°C, more preferably 80°C to 140°C. The heating time is preferably 10 seconds to 1000 seconds, more preferably 10 seconds to 500 seconds. Heating can be performed using mechanisms included in conventional exposure machines and / or developing machines, or using a heating plate, etc.

[0035] <Step 3> Step 3 is a step of forming a pattern by performing a developing process on the laminate irradiated with an electron beam. The developing solution used in the developing process may be an alkaline developing solution or a developing solution containing an organic solvent (hereinafter also referred to as an organic developing solution).

[0036] Examples of developing methods include: immersing the substrate in a tank filled with developing solution for a certain time (immersion method); using surface tension to accumulate developing solution on the substrate surface and allowing it to stand for a certain time for development (puddle method); spraying developing solution onto the substrate surface (spray method); and continuously spraying developing solution onto a substrate rotating at a certain speed while scanning the developing solution nozzle at a certain speed (dynamic distribution method). Additionally, after the developing step, a step can be performed to stop developing by replacing the solvent with another solvent. The developing time is preferably 10 seconds to 300 seconds, more preferably 20 seconds to 120 seconds. The temperature of the developing solution is preferably 0°C to 50°C, more preferably 15°C to 35°C.

[0037] The alkaline developer is preferably an alkaline aqueous solution containing an alkali. There are no particular limitations on the type of alkaline aqueous solution; examples include alkaline aqueous solutions containing quaternary ammonium salts, such as tetramethylammonium hydroxide, inorganic alkalis, primary amines, secondary amines, tertiary amines, alkanolamines, or cyclic amines. Among these, an aqueous solution containing a quaternary ammonium salt, such as tetramethylammonium hydroxide (TMAH), is preferred as the alkaline developer. Appropriate amounts of alcohols and surfactants may also be added to the alkaline developer. The alkali concentration of the alkaline developer is typically 0.1% to 20% by mass. Furthermore, the pH of the alkaline developer is typically 10.0 to 15.0.

[0038] As an organic developer, it is preferably a developer containing at least one organic solvent selected from the group consisting of ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents and hydrocarbon solvents.

[0039] The solvent can be mixed with multiple solvents, or with solvents other than those mentioned above, or with water. The water content of the overall developer is preferably less than 50% by mass, more preferably less than 20% by mass, and even more preferably less than 10% by mass, and particularly preferably substantially free of water. The content of organic solvent relative to the total amount of the developer is preferably 50% to 100% by mass, more preferably 80% to 100% by mass, and even more preferably 90% to 100% by mass.

[0040] <Other Steps> The pattern forming method preferably includes a step of cleaning with a rinsing solution after step 3.

[0041] As a rinsing solution used in the rinsing step after the development step using an alkaline developer, pure water can be cited as an example. An appropriate amount of surfactant may also be added to the rinsing solution.

[0042] The rinsing solution used in the rinsing step after the developing step using an organic developer is not particularly limited as long as it does not dissolve the pattern, and a solution containing a common organic solvent can be used. Preferably, the rinsing solution is an organic solvent containing at least one organic solvent selected from the group consisting of hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents.

[0043] The method of the rinsing step is not particularly limited. Examples include: continuously spraying rinsing liquid onto a substrate rotating at a certain speed (spin coating method); immersing the substrate in a tank filled with rinsing liquid for a certain time (immersion method); and spraying rinsing liquid onto the surface of the substrate (spraying method). Furthermore, the pattern forming method of the present invention may also include a heating step (post-bake) after the rinsing step. This step removes the developer and rinsing liquid remaining between and inside the pattern. Additionally, this step also forms a resist pattern and improves the surface roughness of the pattern. The heating temperature in the heating step after the rinsing step is preferably 40°C to 250°C (preferably 90°C to 200°C), and the heating time is preferably 10 seconds to 3 minutes (preferably 30 seconds to 120 seconds).

[0044] Alternatively, the formed pattern can be used as a mask to perform etching on the substrate. That is, the pattern formed in step 3 can also be used as a mask to process the substrate and form a pattern on the substrate. There is no particular limitation on the substrate processing method, but it is preferable to form a pattern on the substrate by dry etching using the pattern formed in step 3 as a mask. Dry etching is preferably oxygen plasma etching.

[0045] The various materials used in the pattern forming method of the present invention (e.g., compositions for forming resist layers, compositions for forming intermediate layers, compositions for forming conductive layers, developing solutions, and rinsing solutions, etc.) are preferably free of impurities such as metals. The content of impurities contained in these materials is preferably less than 1 ppm by mass, more preferably less than 10 ppb by mass, further preferably less than 100 ppt by mass, particularly preferably less than 10 ppt by mass, and most preferably less than 1 ppt by mass. Examples of metallic impurities include, for instance: Na, K, Ca, Fe, Cu, Mg, Al, Li, Cr, Ni, Sn, Ag, As, Au, Ba, Cd, Co, Pb, Ti, V, W, and Zn.

[0046] As a method for removing impurities such as metals from various materials, filtration using a filter can be cited as an example. Details of filtration using a filter are described in paragraph

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

[0047] In addition, as a method to reduce impurities such as metals contained in various materials, the following methods can be listed, for example: selecting raw materials with low metal content as raw materials for constituting various materials, filtering the raw materials constituting various materials with filters, and lining the device with Teflon (registered trademark) and distilling under conditions that suppress contamination as much as possible.

[0048] In addition to filtration by a filter, impurities can also be removed using an adsorbent material, or a combination of filtration and adsorbent material can be used. As an adsorbent material, known adsorbent materials can be used, such as inorganic adsorbent materials like silicone and zeolite, and organic adsorbent materials like activated carbon. To reduce impurities such as metals contained in these materials, it is necessary to prevent the introduction of metal impurities during the manufacturing process. The content of metal components in the cleaning solution used to clean the manufacturing apparatus can be measured to confirm whether metal impurities have been sufficiently removed from the manufacturing apparatus. The content of metal components in the used cleaning solution is preferably 100 parts per trillion (ppt), more preferably 10 ppt, and even more preferably 1 ppt.

[0049] To prevent malfunctions in the chemical solution piping and various components (filters, O-rings, tubes, etc.) caused by static electricity and subsequent electrostatic discharge, conductive compounds may be added to organic processing solutions such as rinsing solutions. There are no particular limitations on the conductive compounds; methanol is an example. There are no particular limitations on the amount added, but for maintaining better developing or rinsing characteristics, it is preferably 10% by mass or less, more preferably 5% by mass or less. For chemical solution piping, various pipes coated with SUS (stainless steel) or antistatic-treated polyethylene, polypropylene, or fluoropolymers (such as polytetrafluoroethylene or perfluoroalkoxy resins) can be used, for example. Similarly, antistatic-treated polyethylene, polypropylene, or fluoropolymers (such as polytetrafluoroethylene or perfluoroalkoxy resins) can also be used for filters and O-rings.

[0050] <Manufacturing Method of Electronic Components> Furthermore, the present invention also relates to a manufacturing method of an electronic component including the pattern forming method described above, and an electronic component manufactured by the manufacturing method described above. The electronic component of the present invention is preferably mounted in electrical and electronic devices (home appliances, office automation (OA), media-related devices, optical devices, and communication devices, etc.).

[0051] <Resist Layer> The resist layer is a layer used to form a pattern by electron beam irradiation and development. The resist layer may also contain a resin (hereinafter, also referred to as resin (A)) whose solubility relative to the developer changes due to the action of an acid. Resin (A) will be described in detail later. Resin (A) preferably contains repeating units having residues formed by removing a hydrogen atom from a compound that generates an acid by electron beam irradiation. In other words, the resist layer preferably satisfies the following requirement 2. Requirement 2: Resin (A) contains repeating units (hereinafter, also referred to as specific units) having residues formed by removing a hydrogen atom from a compound that generates an acid by electron beam irradiation.

[0052] When requirement 2 is satisfied, the content of a specific unit relative to the total mass of the resist layer is preferably 10% by mass or more, more preferably 20% by mass or more. There is no particular upper limit, but it is preferably 50% by mass or less.

[0053] Furthermore, as described below, the resist layer preferably contains a compound that generates acid upon irradiation by an electron beam. In other words, the resist layer preferably satisfies the following requirement 1. Requirement 1: The resist layer contains a compound that generates acid upon irradiation by an electron beam. When requirement 1 is satisfied, the content of the compound that generates acid upon irradiation by an electron beam is preferably 10% by mass or more, more preferably 20% by mass or more, relative to the total mass of the resist layer. There is no particular upper limit, but it is preferably 50% by mass or less.

[0054] <Resin (A)> The resist layer may also contain resin (A). Resin (A) may be a resin whose solubility relative to the developer increases due to the action of acid, or a resin whose solubility relative to the developer decreases due to the action of acid. As resin (A), it is generally preferred to be a resin having a group that increases in polarity due to decomposition by the action of acid (hereinafter also referred to as "acid-decomposable group"), and more preferably a resin containing repeating units having acid-decomposable groups. Therefore, in the pattern forming method of the present invention, typically when an alkaline developer is used as the developer, a positive pattern can be formed more preferably, and when an organic developer is used as the developer, a negative pattern can be formed more preferably. As repeating units having acid-decomposable groups, in addition to (repeating units having acid-decomposable groups) described later, it is preferred to be (repeating units having acid-decomposable groups containing unsaturated bonds).

[0055] (Repeating unit with acid-degradable group) An acid-degradable group refers to a group that decomposes under the action of an acid to produce a polar group. Preferably, the acid-degradable group is a structure with a removable group protecting the polar group after it has been removed by the action of an acid. That is, the resin (A) contains a repeating unit having a group that decomposes under the action of an acid to produce a polar group. The resin containing this repeating unit becomes more polar under the action of an acid, and its solubility relative to alkaline developing solutions increases, while its solubility relative to organic solvents decreases. As a polar group, a base-soluble group is preferred, and examples include: carboxyl, phenolic hydroxyl, fluorinated alcohol, sulfonic acid, phosphoric acid, sulfonamide, sulfonylimido, (alkylsulfonyl)(alkylcarbonyl)methylene, (alkylsulfonyl)(alkylcarbonyl)imido, bis(alkylcarbonyl)methylene, bis(alkylcarbonyl)imido, bis(alkylsulfonyl)methylene, bis(alkylsulfonyl)imido, tri(alkylcarbonyl)methylene and tri(alkylsulfonyl)methylene, and other acidic groups, as well as alcoholic hydroxyl groups. Among these, as a polar group, carboxyl, phenolic hydroxyl, fluorinated alcohol (preferably hexafluoroisopropanol), or sulfonic acid are preferred. Therefore, resin (A) is preferably a repeating unit containing a group that decomposes to produce a carboxyl group by the action of an acid, or a repeating unit containing a group that decomposes to produce a phenolic hydroxyl group by the action of an acid. Furthermore, the repeating unit containing a group that decomposes to produce a phenolic hydroxyl group by the action of an acid is preferably a releasing group that is released by the action of an acid, represented by the group represented by formula (Y1) described later.

[0056] As a detaching group that is released by the action of an acid, examples 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(R36)(R37)(OR38) Formula (Y4): -C(Rn)(H)(Ar

[0057] In formulas (Y1) and (Y2), Rx1 to Rx3 independently represent alkyl (straight-chain or branched-chain), cycloalkyl (monocyclic or polycyclic), alkenyl (straight-chain or branched-chain), or aryl (monocyclic or polycyclic). Furthermore, when all of Rx1 to Rx3 are alkyl (straight-chain or branched-chain), it is preferable that at least two of Rx1 to Rx3 are methyl. Preferably, Rx1 to Rx3 independently represent straight-chain or branched-chain alkyl groups, and more preferably, Rx1 to Rx3 independently represent straight-chain alkyl groups. The two of Rx1 to Rx3 can be bonded to form a monocyclic or polycyclic ring. Preferably, the alkyl groups of Rx1 to Rx3 are alkyl groups with 1 to 5 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tributyl. The cycloalkyl groups Rx1 to Rx3 are preferably monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl, or polycyclic cycloalkyl groups such as norbornyl, tetracyclic decyl, tetracyclic dodecyl, and adamantyl. The aryl groups Rx1 to Rx3 are preferably aryl groups having 6 to 10 carbon atoms, such as phenyl, naphthyl, and anthracene. The alkenyl groups Rx1 to Rx3 are preferably vinyl. The ring formed by the two bonds of Rx1 to Rx3 is preferably a cycloalkyl group. The cycloalkyl group formed by the two bonds of Rx1 to Rx3 is preferably a monocyclic cycloalkyl group such as cyclopentyl or cyclohexyl, or a polycyclic cycloalkyl group such as norbornyl, tetracyclic decyl, tetracyclic dodecyl, or adamantyl, and more preferably a monocyclic cycloalkyl group having 5 to 6 carbon atoms. In the cycloalkyl group formed by the two bonds of Rx1 to Rx3, one of the methylene groups constituting the ring may be substituted with a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylidene. In addition, one or more of the ethyl groups constituting the cycloalkane ring in these cycloalkyl groups may be substituted with vinyl groups. The group represented by formula (Y1) or formula (Y2) is preferably, for example, Rx1 is methyl or ethyl, and Rx2 and Rx3 are bonded to form the cycloalkyl group.

[0058] In formula (Y3), R36 to R38 independently represent a hydrogen atom or a monovalent organic group. R37 and R38 can bond to each other to form a ring. Examples of monovalent organic groups include alkyl, cycloalkyl, aryl, aralkyl, and alkenyl. R36 is also preferably a hydrogen atom. Furthermore, the alkyl, cycloalkyl, aryl, and aralkyl groups may contain heteroatoms such as oxygen atoms and / or groups containing heteroatoms such as carbonyl groups. For example, in the alkyl, cycloalkyl, aryl, and aralkyl groups, one or more methylene groups may be substituted with heteroatoms such as oxygen atoms and / or groups containing heteroatoms such as carbonyl groups. In addition, R38 can bond to other substituents in the main chain of the repeating unit to form a ring. The group formed by R38 bonding to other substituents in the main chain of the repeating unit is preferably an alkyl group such as methylene.

[0059] As for formula (Y3), it is preferred to be the basis represented by the following formula (Y3-1).

[0060] [Chemical 1]

[0061] Here, L1 and L2 independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a group composed of these (e.g., a group composed of an alkyl group and an aryl group). M represents a single bond or a divalent linked group. Q represents an alkyl group that may contain heteroatoms, a cycloalkyl group that may contain heteroatoms, an aryl group, an amino group, an ammonium group, a mercapto group, a cyano group, an aldehyde group that may contain heteroatoms, or a group composed of these (e.g., a group composed of an alkyl group and a cycloalkyl group). One of the alkyl and cycloalkyl groups, for example, the methylene group, may be substituted with a heteroatom such as an oxygen atom, or a group containing a heteroatom such as a carbonyl group. Furthermore, it is preferred that 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 composed of an alkyl group and an aryl group. At least two of Q, M, and L1 can be bonded to form a ring (preferably a 5-membered ring or a 6-membered ring). Regarding the refinement of the pattern, L2 is preferably a secondary or tertiary alkyl group, more preferably a tertiary alkyl group. Examples of secondary alkyl groups include isopropyl, cyclohexyl, and norbornyl, while examples of tertiary alkyl groups include tributyl and adamantyl. In these forms, due to the increased Tg (glass transition temperature) and activation energy, fogging can be suppressed in addition to ensuring film strength.

[0062] In formula (Y4), Ar represents an aromatic cycloalkane group. Rn represents an alkyl, cycloalkyl, or aryl group. Rn and Ar can also be bonded to each other to form a non-aromatic ring. Ar is preferably an aryl group.

[0063] In terms of the excellent acid decomposability of the repeating unit, when the non-aromatic ring in the detachment group protecting the polar group is directly bonded to the polar group (or its residue), the ring member atom adjacent to the ring member atom in the non-aromatic ring that is directly bonded to the polar group (or its residue) is preferably not a halogen atom such as a fluorine atom as a substituent.

[0064] In addition to the above, the detaching group that is released by the action of acid may also be 2-cyclopentenyl with a substituent (alkyl group, etc.) such as 3-methyl-2-cyclopentenyl, and cyclohexyl with a substituent (alkyl group, etc.) such as 1,1,4,4-tetramethylcyclohexyl.

[0065] The repeating unit having an acid-decomposable group is preferably the repeating unit represented by formula (A).

[0066] [Chemical 2]

[0067] L1 represents a divalent linker that may have a fluorine atom or an iodine atom; R1 represents a hydrogen atom, a fluorine atom, an iodine atom, an alkyl group that may have a fluorine atom or an iodine atom, or an aryl group that may have a fluorine atom or an iodine atom; and R2 represents a librarian group that is liberated by the action of an acid and may have a fluorine atom or an iodine atom. At least one of L1, R1, and R2 has a fluorine atom or an iodine atom. L1 represents a divalent linker that may have a fluorine atom or an iodine atom. Examples of divalent linkers that may have a fluorine atom or an iodine atom include -CO-, -O-, -S, -SO-, -SO2-, hydrocarbon groups that may have a fluorine atom or an iodine atom (e.g., alkyl, cycloalkyl, alkenyl, and aryl groups), and linkers formed by multiple linkages of these. Wherein, L1 is preferably -CO-, aryl, or -aryl-alkyl-with fluorine or iodine atoms, more preferably -CO- or -aryl-alkyl-with fluorine or iodine atoms. As an aryl group, phenyl is preferred. The alkyl group can be linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 3. The total number of fluorine and iodine atoms contained in the alkyl group having fluorine or iodine atoms is not particularly limited, but is preferably 2 or more, more preferably 2 to 10, and even more preferably 3 to 6.

[0068] R1 represents a hydrogen atom, a fluorine atom, an iodine atom, an alkyl group that may have fluorine or iodine atoms, or an aryl group that may have fluorine or iodine atoms. The alkyl group may be linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but is preferably 1 to 10, more preferably 1 to 3. The total number of fluorine and iodine atoms contained in the alkyl group having fluorine or iodine atoms is not particularly limited, but is preferably 1 or more, more preferably 1 to 5, and even more preferably 1 to 3. The alkyl group may also contain heteroatoms such as oxygen atoms other than halogen atoms.

[0069] R2 represents a detaching group that is released by the action of an acid and may have a fluorine atom or an iodine atom. Examples of detaching groups that may have a fluorine atom or an iodine atom include the detaching groups represented by the formulas (Y1) to (Y4) that have a fluorine atom or an iodine atom.

[0070] The repeating unit having an acid-decomposable group is preferably the repeating unit represented by formula (AI).

[0071] [Chemical 3]

[0072] In formula (AI), Xa1 represents a hydrogen atom or an alkyl group that may have substituents. T represents a single bond or a divalent linkage. Rx1 to Rx3 independently represent alkyl (straight-chain or branched-chain), cycloalkyl (monocyclic or polycyclic), alkenyl (straight-chain or branched-chain), or aryl (monocyclic or polycyclic). Wherein, if all of Rx1 to Rx3 are alkyl (straight-chain or branched-chain), it is preferable that at least two of Rx1 to Rx3 are methyl. The two of Rx1 to Rx3 may be bonded to form a monocyclic or polycyclic ring (monocyclic or polycyclic cycloalkyl, etc.).

[0073] As an alkyl group represented by Xa1 that may have substituents, examples include methyl or a group represented by -CH2-R11. R11 represents a halogen atom (fluorine atom, etc.), a hydroxyl group, or a monovalent organic group, examples include alkyl groups with 5 or fewer carbon atoms that can be substituted by a halogen atom, acetyl groups with 5 or fewer carbon atoms that can be substituted by a halogen atom, and alkoxy groups with 5 or fewer carbon atoms that can be substituted by a halogen atom, preferably an alkyl group with 3 or fewer carbon atoms, and more preferably a methyl group. As Xa1, it is preferably a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0074] The divalent linker of T can be, for example, an alkyl group, an aromatic cycloyl group, a -COO-Rt- group, and an -O-Rt- group. In this formula, Rt represents an alkyl group or an cycloalkyl group. T is preferably a single bond or a -COO-Rt- group. When T represents a -COO-Rt- group, Rt is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a -CH2- group, a -(CH2)2- group, or a -(CH2)3- group.

[0075] The alkyl groups of Rx1 to Rx3 are preferably alkyl groups with 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tributyl. The cycloalkyl groups of Rx1 to Rx3 are preferably monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl, or polycyclic cycloalkyl groups such as norbornyl, tetracyclodecyl, tetracyclododecyl, and adamantyl. The aryl groups of Rx1 to Rx3 are preferably aryl groups with 6 to 10 carbon atoms, such as phenyl, naphthyl, and anthracene. The alkenyl groups of Rx1 to Rx3 are preferably vinyl. The cycloalkyl groups formed by the two bonds of Rx1 to Rx3 are preferably monocyclic cycloalkyl groups such as cyclopentyl and cyclohexyl. In addition, polycyclic cycloalkyl groups such as norbornyl, tetracyclodecyl, tetracyclododecyl, and adamantyl are preferred. Among them, monocyclic cycloalkyl groups with 5 to 6 carbon atoms are preferred. In the cycloalkyl group formed by the two bonds of Rx1 to Rx3, for example, one of the methylene groups constituting the ring may be substituted with a heteroatom such as an oxygen atom, a group containing a heteroatom such as a carbonyl group, or a vinylene. Additionally, in these cycloalkyl groups, one or more of the ethyl groups constituting the cycloalkane ring may be substituted with vinylene. The repeating unit represented by formula (AI) is preferably, for example, Rx1 being methyl or ethyl, and Rx2 and Rx3 being bonded to form the cycloalkyl group.

[0076] When each of the groups has a substituent, examples of substituents include: alkyl (1 to 4 carbon atoms), halogen atom, hydroxyl group, alkoxy group (1 to 4 carbon atoms), carboxyl group, and alkoxycarbonyl group (2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0077] As the repeating unit represented by formula (AI), it is preferably an acid-degradable (meth)acrylate trialkyl ester repeating unit (Xa1 represents a hydrogen atom or methyl group, and T represents a single bond repeating unit).

[0078] Specific examples of repeating units having acid-decomposable groups are shown below, but the present invention is not limited thereto. Furthermore, in the formula, Xa1 represents H, CH3, CF3 or CH2OH, and Rxa and Rxb each independently represent a straight-chain or branched alkyl group having 1 to 5 carbon atoms.

[0079] [Chemical 4]

[0080] [Chemical 5]

[0081] [Chemical 6]

[0082] [Chemical 7]

[0083] [Chemical 8]

[0084] The resin (A) may also contain repeating units having acid-degradable groups containing unsaturated bonds as repeating units having acid-degradable groups. As repeating units having acid-degradable groups containing unsaturated bonds, the repeating units represented by formula (B) are preferred.

[0085] [Chemical 9]

[0086] In formula (B), Xb represents a hydrogen atom, a halogen atom, or an alkyl group that may have substituents. L represents a single bond or a divalent linker that may have substituents. Ry1 to Ry3 each independently represent a straight-chain or branched-chain alkyl group, a monocyclic or polycyclic cycloalkyl group, an alkenyl group, an alkynyl group, or a monocyclic or polycyclic aryl group. 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. Two of Ry1 to Ry3 can be bonded to form a monocyclic or polycyclic ring (a monocyclic or polycyclic cycloalkyl group, a cycloalkenyl group, etc.).

[0087] As the alkyl group represented by Xb, which may have substituents, examples include methyl or the group represented by -CH2-R11. R11 represents a halogen atom (fluorine atom, etc.), a hydroxyl group, or a monovalent organic group, such as an alkyl group with 5 or fewer carbon atoms that can be substituted by a halogen atom, an alkoxy group with 5 or fewer carbon atoms that can be substituted by a halogen atom, and an alkoxy group with 5 or fewer carbon atoms that can be substituted by a halogen atom, preferably an alkyl group with 3 or fewer carbon atoms, and more preferably a methyl group. As Xb, it is more preferably a hydrogen atom, a fluorine atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group.

[0088] The divalent linker represented by L can be categorized as: -Rt-, -CO-, -COO-Rt-, -COO-Rt-CO-, -Rt-CO-, and -O-Rt-. In this formula, Rt represents an alkyl group, an cycloalkyl group, or an aromatic cycloalkyl group, preferably an aromatic cycloalkyl group. L is preferably -Rt-, -CO-, -COO-Rt-CO-, or -Rt-CO-. Rt may have substituents such as halogen atoms, hydroxyl groups, or alkoxy groups. An aromatic group is preferred.

[0089] The alkyl group of Ry1 to Ry3 is preferably an alkyl group with 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tributyl. The cycloalkyl group of Ry1 to Ry3 is preferably a monocyclic cycloalkyl group such as cyclopentyl and cyclohexyl, or a polycyclic cycloalkyl group such as norbornyl, tetracyclodecyl, tetracyclododecyl, and adamantyl. The aryl group of Ry1 to Ry3 is preferably an aryl group with 6 to 10 carbon atoms, such as phenyl, naphthyl, and anthracene. The alkenyl group of Ry1 to Ry3 is preferably vinyl. The alkynyl group of Ry1 to Ry3 is preferably ethynyl. The cycloalkenyl group of Ry1 to Ry3 is preferably a cycloalkyl group containing a double bond in part of a monocyclic cycloalkyl group such as cyclopentyl and cyclohexyl. The cycloalkyl group formed by the two bonds of Ry1 to Ry3 is preferably a monocyclic cycloalkyl group such as cyclopentyl or cyclohexyl, or a polycyclic cycloalkyl group such as norbornyl, tetracyclic decyl, tetracyclic dodecyl, and adamantyl. More preferably, it is a monocyclic cycloalkyl group having 5 to 6 carbon atoms. In the cycloalkyl or cycloalkenyl group formed by the two bonds of Ry1 to Ry3, for example, one of the methylene groups constituting the ring may be substituted with a heteroatom such as an oxygen atom, a carbonyl group, a group containing a heteroatom such as -SO2- or -SO3-, a vinyl group, or a combination thereof. Furthermore, in these cycloalkyl or cycloalkenyl groups, one or more of the ethyl groups constituting the cycloalkane ring or cycloalkene ring may be substituted with vinyl groups. The repeating unit represented by formula (B) is preferably, for example, Ry1 being methyl, ethyl, vinyl, allyl, or aryl, and Ry2 and Rx3 being bonded to form the cycloalkyl or cycloalkenyl group.

[0090] When each of the groups has a substituent, examples of substituents include: alkyl (1 to 4 carbon atoms), halogen atom, hydroxyl group, alkoxy group (1 to 4 carbon atoms), carboxyl group, and alkoxycarbonyl group (2 to 6 carbon atoms). The number of carbon atoms in the substituent is preferably 8 or less.

[0091] The repeating unit represented by formula (B) is preferably an acid-degradable (meth)acrylate ter ester repeating unit (Xb represents a hydrogen atom or methyl and L represents a -CO- group repeating unit), an acid-degradable hydroxystyrene ter alkyl ether repeating unit (Xb represents a hydrogen atom or methyl and L represents a phenyl repeating unit), or an acid-degradable styrene carboxylic acid ter ester repeating unit (Xb represents a hydrogen atom or methyl and L represents a -Rt-CO- group (Rt is an aromatic group) repeating unit).

[0092] Specific examples of repeating units having acid-decomposable groups containing unsaturated bonds are shown below, but the present invention is not limited thereto. Furthermore, in the formula, Xb and L1 represent any of the substituents and linking groups described above, Ar represents an aromatic group, R represents a hydrogen atom, alkyl, cycloalkyl, aryl, aralkyl, alkenyl, hydroxyl, alkoxy, acetoxy, cyano, nitro, amino, halogen atom, ester group (-OCOR''' or -COOR''': R'''' is an alkyl or fluorinated alkyl with 1 to 20 carbon atoms), or carboxyl group, etc., R' represents a straight-chain or branched-chain alkyl, monocyclic or polycyclic cycloalkyl, alkenyl, alkynyl, or monocyclic or polycyclic aryl, Q represents a heteroatom such as an oxygen atom, carbonyl, -SO2- group and -SO3- group, vinylidene group, or a combination thereof, and n and m represent integers of 0 or more.

[0093] [Chemical 10]

[0094] [Chemical 11]

[0095] [Chemical 12]

[0096] [Chemical 13]

[0097] The content of repeating units having acid-decomposable groups is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more, relative to all repeating units in resin (A). Furthermore, as an upper limit, it 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, relative to all repeating units in resin (A).

[0098] The content of repeating units having acid-decomposable groups containing unsaturated bonds is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more, relative to all repeating units in resin (A). Furthermore, as an upper limit, it is preferably 80 mol% or less, more preferably 70 mol% or less, and especially preferably 60 mol% or less, relative to all repeating units in resin (A).

[0099] The resin (A) may also contain at least one repeating unit selected from the group consisting of the following group A, and / or at least one repeating unit selected from the group consisting of the following group B. Group A: a group consisting of repeating units of the following (20) to (29). (20) Repeating unit with an acid group as described below (21) Repeating unit with a fluorine atom, bromine atom, or iodine atom as described below, which does not have an acid-decomposing group or any of the acid groups as described below (22) Repeating unit with a lactone group, sulcinolone group, or carbonate group as described below (23) Repeating unit with an acid-generating group as described below (24) Repeating unit represented by formula (V-1) as described below or formula (V-2) as described below (25) Repeating unit represented by formula (A) as described below (26) Repeating unit represented by formula (B) as described below (27) Repeating unit represented by formula (C) as described below (28) Repeating unit represented by formula (D) as described below (29) Repeating unit represented by formula (E) as described below Group B: Group of repeating units including (30) to (32) as described below. (30) The repeating unit described below having at least one group selected from lactone, sulcinolone, carbonate, hydroxyl, cyano, and base-soluble group. (31) The repeating unit described below having an alicyclic hydrocarbon structure and not exhibiting acid decomposition properties. (32) The repeating unit described below not having either a hydroxyl or cyano group, represented by formula (III).

[0100] Resin (A) preferably has acid groups, and more preferably contains repeating units with acid groups as described later. Furthermore, the definition of acid groups will be explained later along with the preferred state of repeating units with acid groups. When resin (A) has acid groups, the interaction between resin (A) and the acid generated by the acid-generating agent is more excellent. As a result, acid diffusion can be further suppressed, and the cross-sectional shape of the formed pattern can be further rectangularized.

[0101] (Repeating Units with Acid Groups) Resin (A) may also contain repeating units with acid groups. Preferably, the acid group has a pKa of 13 or less. The acid dissociation constant of the acid group is preferably 13 or less, more preferably 3 to 13, and even more preferably 5 to 10. When resin (A) has acid groups with a pKa of 13 or less, the content of the acid group in resin (A) is not particularly limited, and is generally 0.2 mmol / g to 6.0 mmol / g. Preferably, it is 0.8 mmol / g to 6.0 mmol / g, more preferably 1.2 mmol / g to 5.0 mmol / g, and even more preferably 1.6 mmol / g to 4.0 mmol / g. If the content of the acid group is within the aforementioned range, development proceeds well, and the resulting pattern shape and resolution are excellent. The acid group is preferably, for example, a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), a sulfonic acid group, a sulfonamide group, or an isopropanol group, more preferably a phenolic hydroxyl group or a fluorinated alcohol group, and even more preferably a fluorinated alcohol group. Furthermore, in the hexafluoroisopropanol group, one or more fluorine atoms (preferably one to two) may be substituted with a group other than a fluorine atom (such as an alkoxycarbonyl group). The acid group is also preferably -C(CF3)(OH)-CF2- formed in this way. Additionally, one or more fluorine atoms may also be substituted with a group other than a fluorine atom to form a ring containing -C(CF3)(OH)-CF2-. The repeating unit having the acid group is preferably a repeating unit different from the repeating unit. The repeating unit having the acid group may also have a fluorine atom or an iodine atom.

[0102] The following repeating units can be listed as repeating units having acid groups.

[0103] [Chemical 14]

[0104] The repeating unit having an acid group is preferably the repeating unit represented by the following formula (1).

[0105] [Chemistry 15]

[0106] In formula (1), A represents a hydrogen atom, alkyl, cycloalkyl, halogen atom, or cyano. R represents a halogen atom, alkyl, cycloalkyl, aryl, alkenyl, aralkyl, alkoxy, alkylcarbonyloxy, alkylsulfonyloxy, alkyloxycarbonyl, or aryloxycarbonyl, which may be the same or different when multiple R are present. When multiple R are present, they may combine to form a ring. R is preferably a hydrogen atom. a represents an integer from 1 to 3. b represents an integer from 0 to (5-a).

[0107] The following examples illustrate repeating units with acid groups. In the formula, a represents 1 or 2.

[0108] [Chemical 16]

[0109] [Chemistry 17]

[0110] [Chemistry 18]

[0111] [Chemistry 19]

[0112] Furthermore, the repeating unit is preferably the repeating unit specifically described below. In the formula, R represents a hydrogen atom or a methyl group, and a represents 2 or 3.

[0113] [Chemical 20]

[0114] [Chemical 21]

[0115] The content of repeating units having acid groups is preferably 10 mol% or more, more preferably 15 mol% or more, relative to all repeating units in resin (A). Furthermore, as an upper limit, it is preferably 70 mol% or less, more preferably 65 mol% or less, and even more preferably 60 mol% or less, relative to all repeating units in resin (A).

[0116] (Repeating unit having fluorine, bromine, or iodine atoms but not having either an acid-decomposable group or an acid group) Resin (A) may also have repeating units having fluorine, bromine, or iodine atoms but not having either an acid-decomposable group or an acid group (hereinafter also referred to as Unit X), which are different from the <repeating unit having either an acid-decomposable group or an acid group> and <repeating unit having an acid-generating group> described herein. Furthermore, the <repeating unit having either an acid-decomposable group or an acid group but having fluorine, bromine, or iodine atoms> described herein is preferably different from other types of repeating units belonging to Group A, such as <repeating units having lactone, sulopentalide, or carbonate groups> and <repeating units having acid-generating groups> described later.

[0117] As unit X, it is preferably the repeating unit represented by equation (C).

[0118] [Chemistry 22]

[0119] L5 represents a single bond or an ester group. R9 represents a hydrogen atom, or an alkyl group that may have a fluorine atom or an iodine atom. R10 represents a hydrogen atom, an alkyl group that may have a fluorine atom or an iodine atom, a cycloalkyl group that may have a fluorine atom or an iodine atom, an aryl group that may have a fluorine atom or an iodine atom, or a group composed of these.

[0120] The following are examples of repeating units having fluorine or iodine atoms.

[0121] [Chemistry 23]

[0122] The content of unit X is preferably 0 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, relative to all repeating units in resin (A). Furthermore, as an upper limit, it is preferably 50 mol% or less, more preferably 45 mol% or less, and even more preferably 40 mol% or less, relative to all repeating units in resin (A).

[0123] Among the repeating units of resin (A), the total content of repeating units containing at least one of fluorine, bromine, and iodine atoms, relative to all repeating units of resin (A), is preferably 10 mol% or more, more preferably 20 mol% or more, further preferably 30 mol% or more, and even more preferably 40 mol% or more. There is no particular limitation on the upper limit; for example, it may be 100 mol% or less relative to all repeating units of resin (A). Furthermore, examples of repeating units containing at least one of fluorine, bromine, and iodine atoms include: repeating units having fluorine, bromine, or iodine atoms and having an acid-decomposing group; repeating units having fluorine, bromine, or iodine atoms and having an acid group; and repeating units having fluorine, bromine, or iodine atoms.

[0124] (Repeating unit having lactone, sulopentalide, or carbonate groups) The resin (A) may also contain a repeating unit (hereinafter also referred to as "unit Y") having at least one group selected from the group consisting of lactone, sulopentalide, and carbonate groups. Unit Y is also preferably free of acid groups such as hydroxyl and hexafluoropropanol groups.

[0125] As a lactone group or sulfonolactone group, it is acceptable as long as it has a lactone structure or a sulfonolactone structure. Preferably, the lactone structure or sulfonolactone structure is a 5-membered ring lactone structure to a 7-membered ring lactone structure or a 5-membered ring sulfonolactone structure to a 7-membered ring sulfonolactone structure. More preferably, it is formed by ring condensation of other ring structures in the form of a bicyclic or spirocyclic structure within the 5-membered ring lactone structure to a 7-membered ring lactone structure, or by ring condensation of other ring structures in the form of a bicyclic or spirocyclic structure within the 5-membered ring sulfonolactone structure to a 7-membered ring sulfonolactone structure. The resin (A) preferably comprises repeating units having a lactone group or sulfonolactone group formed by removing one or more hydrogen atoms from the ring member atoms of a lactone structure represented by any one of the following formulas (LC1-1) to (LC1-21), or a sulfonolactone structure represented by any one of the following formulas (SL1-1) to (SL1-3). In addition, lactone or sulopentalide groups can also be directly bonded to the main chain. For example, the ring-membered atoms of lactone or sulopentalide groups can also form the main chain of resin (A).

[0126] [Chemistry 24]

[0127] The lactone or sulopentalide structure may also have substituents (Rb2). Preferred substituents (Rb2) include: alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 7 carbon atoms, alkoxy groups having 1 to 8 carbon atoms, alkoxycarbonyl groups having 1 to 8 carbon atoms, carboxyl groups, halogen atoms, cyano groups, and acid-degradable groups. n2 represents an integer from 0 to 4. When n2 is 2 or more, the multiple Rb2 groups may be different, and the multiple Rb2 groups may bond together to form a ring.

[0128] A repeating unit having a lactone structure represented by any of the formulas (LC1-1) to (LC1-21) or a sulfonolactone structure represented by any of the formulas (SL1-1) to (SL1-3) may be, for example, a repeating unit represented by the following formula (AI).

[0129] [Chemistry 25]

[0130] In formula (AI), Rb0 represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. Preferred substituents for the alkyl group of Rb0 include hydroxyl and halogen atoms. Examples of halogen atoms for Rb0 include fluorine, chlorine, bromine, and iodine atoms. Rb0 is preferably a hydrogen atom or a methyl group. Ab represents a single bond, an alkyl group, a divalent linker having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, a carboxyl group, or a divalent group composed of these. Preferably, Ab is a single bond or a linker represented by -Ab1-CO2-. Ab1 is a straight-chain or branched alkyl group, or a monocyclic or polycyclic cycloalkyl group, preferably methylene, ethyl, cyclohexyl, adamantyl, or norbornyl. V represents a group formed by removing a hydrogen atom from the ring member atom of the lactone structure represented by any of the formulas (LC1-1) to (LC1-21), or a group formed by removing a hydrogen atom from the ring member atom of the sulfonyl lactone structure represented by any of the formulas (SL1-1) to (SL1-3).

[0131] When an optical isomer is present in a repeating unit having a lactone group or a sulcinolone group, any optical isomer may be used. Alternatively, a single optical isomer may be used alone, or multiple optical isomers may be used in combination. When primarily using one optical isomer, its optical purity (ee) is preferably 90 or higher, more preferably 95 or higher.

[0132] The carbonate group is preferably a cyclic carbonate group. The repeating unit having a cyclic carbonate group is preferably the repeating unit represented by the following formula (A-1).

[0133] [Chemical 26]

[0134] In formula (A-1), RA1 represents a hydrogen atom, a halogen atom, or a monovalent organic group (preferably methyl). n represents an integer greater than or equal to 0. RA2 represents a substituent. When n is 2 or more, multiple RA2s may be identical or different. A represents a single bond or a divalent linker. As the divalent linker, preferably an alkyl group, a divalent linker having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, a carboxyl group, or a divalent group formed by combining these. Z represents a group that forms a monocyclic or polycyclic ring together with the group represented by -O-CO-O- in the formula.

[0135] The following example illustrates unit Y.

[0136] [Chemistry 27]

[0137] [Chemistry 28]

[0138] [Chemistry 29]

[0139] The content of unit Y is preferably 1 mol% or more, more preferably 10 mol% or more, relative to all repeating units in resin (A). Furthermore, as an upper limit, it is preferably 85 mol% or less, more preferably 80 mol% or less, further preferably 70 mol% or less, and especially preferably 60 mol% or less, relative to all repeating units in resin (A).

[0140] (Repetitive unit with acid-generating group) The resin (A) may also contain repeating units other than those described above, which are formed by removing a hydrogen atom from a compound that generates acid by irradiation of an electron beam (hereinafter also referred to as "acid-generating group"). As repeating units with acid-generating groups, repeating units represented by formula (4) can be listed.

[0141] [Chemical 30]

[0142] R41 represents a hydrogen atom or a methyl group. L41 represents a single bond or a divalent group. L42 represents a divalent group. R40 represents a residue formed by removing a hydrogen atom from a compound that produces an acid by irradiation with an electron beam. The following are examples of repeating units having an acid-producing group.

[0143] [Chemistry 31]

[0144] In addition, as the repeating unit represented by formula (4), for example, the repeating units described in paragraphs

[0094] to

[0105] of Japanese Patent Application Publication No. 2014-041327 and the repeating units described in paragraph

[0094] of International Publication No. 2018 / 193954 can be cited.

[0145] The content of repeating units having acid-generating groups is preferably 1 mol% or more, more preferably 5 mol% or more, relative to all repeating units in resin (A). Furthermore, as an upper limit, it is preferably 40 mol% or less, more preferably 35 mol% or less, and even more preferably 30 mol% or less, relative to all repeating units in resin (A).

[0146] (Repeating unit represented by formula (V-1) or formula (V-2) below) Resin (A) may also contain repeating units represented by formula (V-1) or formula (V-2) below. The repeating units represented by formula (V-1) and formula (V-2) below are preferably repeating units different from the repeating units described above.

[0147] [Chemistry 32]

[0148] In the formula, R6 and R7 independently represent a hydrogen atom, hydroxyl group, alkyl group, alkoxy group, acetoxy group, cyano group, nitro group, amino group, halogen atom, ester group (-OCOR or -COOR: R is an alkyl or fluorinated alkyl group with 1 to 6 carbon atoms) or carboxyl group. As an alkyl group, it is preferred to be a straight-chain, branched-chain or cyclic alkyl group with 1 to 10 carbon atoms. n3 represents an integer from 0 to 6. n4 represents an integer from 0 to 4. X4 is a methylene group, an oxygen atom or a sulfur atom. The repeating unit represented by formula (V-1) or formula (V-2) is illustrated below. As a repeating unit represented by formula (V-1) or formula (V-2), the repeating unit described in paragraph

[0100] of International Publication No. 2018 / 193954 can be cited as an example.

[0149] (Repeating Units for Reducing Main Chain Mobility) In terms of suppressing excessive diffusion of acid or pattern collapse during development, the resin (A) preferably has a high glass transition temperature (Tg). The Tg is preferably greater than 90°C, more preferably greater than 100°C, even more preferably greater than 110°C, and especially preferably greater than 125°C. Furthermore, in terms of excellent dissolution rate in the developer, the Tg is preferably below 400°C, more preferably below 350°C. Furthermore, in this specification, the glass transition temperature (Tg) of the polymer such as resin (A) (hereinafter referred to as "Tg of the repeating unit") is calculated by the following method. First, the Tg of the homopolymer containing only each repeating unit contained in the polymer is calculated separately using the Bicerano method. Second, the mass percentage (%) of each repeating unit relative to all repeating units in the polymer is calculated. Next, the Tg of each mass proportion is calculated using the Fox formula (described in Materials Letters 62 (2008) 3152, etc.), and these are summed to form the Tg (°C) of the polymer. The Bicerano method is described in Prediction of polymer properties, Marcel Dekker Inc, New York (1993). Furthermore, the Tg calculated using the Bicerano method can be obtained using the polymer property estimation software MDL Polymer (MDL Information Systems, Inc.).

[0150] In order to increase the Tg of resin (A) (preferably setting the Tg to be greater than 90°C), it is preferable to reduce the mobility of the main chain of resin (A). Methods for reducing the mobility of the main chain of resin (A) include the following methods (a) to (e): (a) Introducing a bulky substituent into the main chain; (b) Introducing multiple substituents into the main chain; (c) Introducing substituents that induce interactions between resins (A) near the main chain; (d) Forming the main chain with a cyclic structure; (e) Linkage between the cyclic structure and the main chain. Furthermore, resin (A) preferably contains repeating units with a Tg of 130°C or higher in homopolymers. Furthermore, there is no particular limitation on the type of repeating units with a Tg of 130°C or higher in homopolymers, as long as the repeating unit has a Tg of 130°C or higher in homopolymers calculated by the Bicerano method. Furthermore, based on the types of functional groups in the repeating units represented by equations (A) to (E) described later, the repeating units corresponding to the Tg of the homopolymer show a temperature above 130°C.

[0151] As an example of a specific method of achieving (a), a method of introducing the repeating unit represented by formula (A) into resin (A) can be cited.

[0152] [Chemistry 33]

[0153] In formula (A), RA represents a group containing a polycyclic structure. Rx represents a hydrogen atom, a methyl group, or an ethyl group. A group containing a polycyclic structure is a group containing multiple ring structures, which may or may not be condensed. As specific examples of repeating units represented by formula (A), those described in paragraphs

[0107] to

[0119] of International Publication No. 2018 / 193954 can be cited.

[0154] As an example of a specific method of achieving (b), a method of introducing the repeating unit represented by formula (B) into resin (A) can be cited.

[0155] [Chemical 34]

[0156] In formula (B), Rb1 to Rb4 independently represent hydrogen atoms or organic groups, and at least two of Rb1 to Rb4 represent organic groups. Furthermore, if at least one organic group is a group with a ring structure directly linked to the main chain of the repeating unit, there are no particular restrictions on the types of other organic groups. Furthermore, if none of the organic groups are groups with a ring structure directly linked to the main chain of the repeating unit, at least two of the organic groups are substituents with three or more constituent atoms other than hydrogen atoms. Specific examples of the repeating unit represented by formula (B) can be cited from paragraphs

[0113] to

[0115] of International Publication No. 2018 / 193954.

[0157] As an example of a specific method of achieving (c), a method of introducing the repeating unit represented by formula (C) into resin (A) can be cited.

[0158] [Chemistry 35]

[0159] In formula (C), Rc1 to Rc4 independently represent hydrogen atoms or organic groups, and at least one of Rc1 to Rc4 is a group containing hydrogen atoms with hydrogen bonding in the number of atoms up to 3, based on the interaction between the main chains of the induced resin (A). Preferably, it is a hydrogen atom with hydrogen bonding in the number of atoms up to 2 (closer to the main chain) based on the interaction between the main chains of the induced resin (A). As specific examples of the repeating unit represented by formula (C), those described in paragraphs

[0119] to

[0121] of International Publication No. 2018 / 193954 can be cited.

[0160] As an example of a specific method of achieving (d), a method of introducing the repeating unit represented by formula (D) into resin (A) can be cited.

[0161] [Chemistry 36]

[0162] In formula (D), "Cyclic" represents a base that forms the main chain in a ring structure. There is no particular limitation on the number of atoms constituting the ring. As specific examples of repeating units represented by formula (D), those described in paragraphs

[0126] to

[0127] of International Publication No. 2018 / 193954 can be cited.

[0163] As an example of a specific method of achieving (e), a method of introducing the repeating unit represented by formula (E) into resin (A) can be cited.

[0164] [Chemistry 37]

[0165] In formula (E), Re independently represents either a hydrogen atom or an organogroup. Examples of organogroups include alkyl, cycloalkyl, aryl, aralkyl, and alkenyl groups, which may have substituents. "Cyclic" is a cyclic group containing carbon atoms in the main chain. There is no particular limitation on the number of atoms contained in the cyclic group. Specific examples of repeating units represented by formula (E) include those described in paragraphs

[0131] to

[0133] of International Publication No. 2018 / 193954.

[0166] (A repeating unit having at least one group selected from lactone, sulopentacaprolactone, carbonate, hydroxyl, cyano, and base-soluble groups) Resin (A) may also contain repeating units having at least one group selected from lactone, sulopentacaprolactone, carbonate, hydroxyl, cyano, and base-soluble groups. As repeating units containing lactone, sulopentacaprolactone, or carbonate groups contained in resin (A), the repeating units described in the section on <Repeating Units Having Lactone, Sulopentacaprolactone, or Carbonate Groups> are examples. Preferred amounts are also as described in the section on <Repeating Units Having Lactone, Sulopentacaprolactone, or Carbonate Groups>.

[0167] The resin (A) may also contain repeating units having hydroxyl or cyano groups. This improves substrate adhesion and developer affinity. The repeating units having hydroxyl or cyano groups are preferably repeating units having an alicyclic hydrocarbon structure substituted with hydroxyl or cyano groups. The repeating units having hydroxyl or cyano groups are preferably not acid-degradable groups. As repeating units having hydroxyl or cyano groups, those described in paragraphs

[0081] to

[0084] of Japanese Patent Application Publication No. 2014-098921 can be cited.

[0168] The resin (A) may also contain repeating units having a base-soluble group. Examples of base-soluble groups include carboxyl groups, sulfonamide groups, sulfonimide groups, disulfonimide groups, and aliphatic alcohol groups (e.g., hexafluoroisopropanol groups) substituted with electron-withdrawing groups at the α-position, with carboxyl groups being preferred. By including repeating units having a base-soluble group in the resin (A), the resolution in contact hole applications is increased. Examples of repeating units having a base-soluble group include those described in paragraphs

[0085] and

[0086] of Japanese Patent Application Publication No. 2014-098921.

[0169] (Repeating unit having an alicyclic hydrocarbon structure and not exhibiting acid decomposition properties) Resin (A) may also contain repeating units having an alicyclic hydrocarbon structure and not exhibiting acid decomposition properties. Examples of such repeating units include repeating units derived from 1-adamantyl (meth)acrylate, diadamantyl (meth)acrylate, tricyclodecyl (meth)acrylate, or cyclohexyl (meth)acrylate.

[0170] (Repeating unit represented by formula (III) without either hydroxyl or cyano groups) The resin (A) may also contain repeating units represented by formula (III) without either hydroxyl or cyano groups.

[0171] [Chemistry 38]

[0172] In formula (III), R5 represents a hydrocarbon group having at least one cyclic structure and not having either a hydroxyl or a cyano group. 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 a acetyl group. As repeating units represented by formula (III) that do not have either a hydroxyl or a cyano group, those described in paragraphs

[0087] to

[0094] of Japanese Patent Application Publication No. 2014-098921 can be cited.

[0173] (Other Repeating Units) Furthermore, resin (A) may also contain repeating units other than the aforementioned repeating units. For example, resin (A) may also contain repeating units selected from the group consisting of repeating units having an oxathiane ring group, repeating units having an oxazolone ring group, repeating units having a dioxane ring group, and repeating units having a hydantoin ring group. Such repeating units are illustrated below.

[0174] [Chemistry 39]

[0175] In addition to the repeating structural units described above, the resin (A) may also contain various repeating structural units for the purpose of adjusting dry etching resistance, standard developer compatibility, substrate adhesion, resist profile, resolution, heat resistance, and sensitivity.

[0176] As resin (A), (especially in the case where the composition is used as a photosensitive or radiosensitive linear resin composition for ArF) it is preferable that all repeating units are composed of repeating units derived from compounds having ethylene unsaturated bonds. It is also particularly 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 both methacrylate and acrylate repeating units. It is preferable that the acrylate repeating units account for 50 moles or less of all repeating units.

[0177] Resin (A) can be synthesized by conventional methods (e.g., free radical polymerization). Based on the polystyrene equivalent obtained using GPC, the weight-average molecular weight of resin (A) is preferably 30,000 or less, more preferably 1,000 to 30,000, even more preferably 3,000 to 30,000, and particularly preferably 5,000 to 15,000. The dispersity (molecular weight distribution) of resin (A) is preferably 1 to 5, more preferably 1 to 3, even more preferably 1.2 to 3.0, and particularly preferably 1.2 to 2.0. The smaller the dispersity, the better the resolution and resist shape, resulting in smoother sidewalls of the resist pattern and better roughness properties.

[0178] When the resist layer contains resin (A), the content of resin (A) is preferably 40.0% to 99.9% by mass, and more preferably 60.0% to 90.0% by mass, relative to the total mass of the resist layer. One type of resin (A) may be used, or multiple types may be used together.

[0179] (Acid-generating compound by electron beam irradiation) The resist layer may also contain a compound that generates acid by electron beam irradiation (hereinafter also referred to as acid generator (B)). The acid generator (B) may be in the form of a low molecular weight compound or in the form incorporated into a portion of a polymer (e.g., resin (A) described later). Alternatively, the low molecular weight compound form and the form incorporated into a portion of a polymer (e.g., resin (A) described later) may be used together. When the acid generator (B) is in the form of a low molecular weight compound, the molecular weight of the acid generator is preferably 3000 or less, more preferably 2000 or less, and even more preferably 1000 or less. There is no particular limitation on the lower limit, but it is preferably 100 or more. When the acid generator (B) is in the form incorporated into a portion of a polymer, it may be incorporated into a portion of resin (A) or into a resin different from resin (A). In this invention, the acid generator (B) is preferably in the form of a low molecular weight compound.

[0180] The pKa of the acid produced by the self-acid generating agent (B) is not particularly limited, and is mostly below 0, but preferably below -1.00 for aspects that are more advantageous to the present invention. The lower limit is not particularly limited, and is mostly above -4.00. The size of the acid produced by the self-acid generating agent (B) is not particularly limited, and is mostly above 150 ų, but preferably above 240 ų for aspects that are more advantageous to the present invention. The upper limit is not particularly limited, and is mostly below 700 ų.

[0181] As an acid generating agent (B), examples include compounds represented by "M+X-" (onium salts), preferably compounds that generate organic acids by means of an electron beam. Examples of said organic acids include: sulfonic acids (aliphatic sulfonic acids, aromatic sulfonic acids, and camphor sulfonic acids, etc.), carboxylic acids (aliphatic carboxylic acids, aromatic carboxylic acids, and aralkyl carboxylic acids, etc.), carbonyl sulfonyliminic acids, bis(alkyl sulfonyliminic acids), and tri(alkyl sulfonyliminic acids).

[0182] In the compound represented by "M+X-", M+ represents an organic cation. There are no particular limitations on the type of organic cation. In addition, the valence of the organic cation may be monovalent or divalent or more. Among them, the organic cation is preferably a cation represented by formula (ZaI) (hereinafter also referred to as "cation (ZaI)") or a cation represented by formula (ZaII) (hereinafter also referred to as "cation (ZaII)").

[0183] [Chemistry 40]

[0184] In the formula (ZaI), R201, R202, and R203 each independently represent an organic group. The number of carbon atoms in the organic groups R201, R202, and R203 is preferably 1 to 30, more preferably 1 to 20. Furthermore, two of R201 to R203 can be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester group, an amino group, or a carbonyl group. Examples of groups formed by the bond between two of R201 to R203 include alkyl groups (e.g., butyl and pentyl) and -CH2-CH2-O-CH2-CH2-.

[0185] As preferred examples of organic cations in formula (ZaI), the following examples include cations (ZaI-1), cation (ZaI-2), organic cations represented by formula (ZaI-3b) (cation (ZaI-3b)) and organic cations represented by formula (ZaI-4b) (cation (ZaI-4b)).

[0186] First, the cation (ZaI-1) will be described. The cation (ZaI-1) is an aryl strontium cation in which at least one of R201 to R203 of the formula (ZaI) is aryl. The aryl strontium cation may be composed entirely of aryl groups from R201 to R203, or may be composed of a portion of aryl groups from R201 to R203 and the remainder being alkyl or cycloalkyl. Alternatively, one of R201 to R203 may be aryl, and the remaining two of R201 to R203 may form a ring structure, or the ring may contain an oxygen atom, a sulfur atom, an ester group, an amino group, or a carbonyl group. As a group formed by two bonds in R201 to R203, examples include one or more alkyl groups (e.g., butyl, pentamyl, and -CH2-CH2-O-CH2-CH2-) in which one methylene group may be substituted with an oxygen atom, sulfur atom, ester group, amide group, and / or carbonyl group. Examples of aryl strontium cations include: triarylstrontium cations, diarylalkylstrontium cations, aryldialkylstrontium cations, diarylcycloalkylstrontium cations, and arylbicycloalkylstrontium cations.

[0187] The aryl group contained in the aryl strontium cation is preferably phenyl or naphthyl, and more preferably phenyl. The aryl group may be an aryl group containing a heterocyclic structure having 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 aryl strontium cation 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 aryl strontium cation is required to be preferably a straight-chain alkyl group having 1 to 15 carbon atoms, a branched-chain alkyl group having 3 to 15 carbon atoms, or a cycloalkyl group having 3 to 15 carbon atoms, and more preferably methyl, ethyl, propyl, n-butyl, dibutyl, tributyl, cyclopropyl, cyclobutyl, or cyclohexyl.

[0188] The substituents that may be present in the aryl, alkyl, and cycloalkyl groups of R201 to R203 are preferably alkyl (e.g., 1 to 15 carbon atoms), cycloalkyl (e.g., 3 to 15 carbon atoms), aryl (e.g., 6 to 14 carbon atoms), alkoxy (e.g., 1 to 15 carbon atoms), cycloalkylalkoxy (e.g., 1 to 15 carbon atoms), halogen atoms (e.g., fluorine and iodine), hydroxyl, carboxyl, ester, sulfinyl, sulfonyl, alkylthio, or phenylthio. Where possible, the substituents may have more substituents, and it is also preferred that the alkyl group has a halogen atom as a substituent, becoming a trifluoromethyl or other haloalkyl group. Furthermore, the substituents are preferably formed by any combination to create an acid-decomposable group. Moreover, an acid-decomposable group refers to a group that decomposes under the action of an acid to produce a polar group, preferably a structure in which the polar group is protected by a release group that is released under the action of an acid. The polar group and the release group are as described above.

[0189] Next, the cation (ZaI-2) will be described. The cation (ZaI-2) is a cation in which R201 to R203 in formula (ZaI) each independently represents an organic group without an aromatic ring. The aromatic ring also includes an aromatic ring containing heteroatoms. The number of carbon atoms in the organic group without an aromatic ring, which is R201 to R203, is preferably 1 to 30, more preferably 1 to 20. R201 to R203 are preferably alkyl, cycloalkyl, allyl or vinyl, more preferably straight-chain or branched-chain 2-oxoalkyl, 2-oxocycloalkyl, or alkoxycarbonylmethyl, and even more preferably straight-chain or branched-chain 2-oxoalkyl.

[0190] The alkyl and cycloalkyl groups of R201 to R203 can be exemplified by: straight-chain alkyl groups having 1 to 10 carbon atoms or branched-chain alkyl groups having 3 to 10 carbon atoms (e.g., methyl, ethyl, propyl, butyl, and pentyl), and cycloalkyl groups having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, and norbornyl). R201 to R203 may also be further substituted with halogen atoms, alkoxy groups (e.g., having 1 to 5 carbon atoms), hydroxyl groups, cyano groups, or nitro groups. In addition, the substituents of R201 to R203 are preferably acid-degradable groups formed independently by any combination of substituents.

[0191] Next, the cation (ZaI-3b) will be explained. The cation (ZaI-3b) is the cation represented by the following formula (ZaI-3b).

[0192] [Chemistry 41]

[0193] In formula (ZaI-3b), R1c to R5c independently represent hydrogen atoms, alkyl, cycloalkyl, aryl, alkoxy, aryloxy, alkoxycarbonyl, alkylcarbonyloxy, cycloalkylcarbonyloxy, halogen atoms, hydroxyl, nitro, alkylthio, or arylthio. R6c and R7c independently represent hydrogen atoms, alkyl (e.g., tertiary butyl), cycloalkyl, halogen atoms, cyano, or aryl. Rx and Ry independently represent alkyl, cycloalkyl, 2-oxoalkyl, 2-oxocycloalkyl, alkoxycarbonylalkyl, allyl, or vinyl. Furthermore, the substituents of R1c to R7c, as well as Rx and Ry, are preferably formed independently by any combination of substituents to create acid-degradable groups.

[0194] Any two or more of R1c to R5c, R5c and R6c, R6c and R7c, R5c and Rx, and Rx and Ry can be bonded to each other to form a ring, which can independently contain an oxygen atom, a sulfur atom, a ketone group, an ester bond, or an amide bond. Examples of such rings include: aromatic or non-aromatic hydrocarbon rings, aromatic or non-aromatic heterocycles, and polycyclic condensation rings formed by combining two or more of these rings. Examples of rings include 3-membered to 10-membered rings, preferably 4-membered to 8-membered rings, and more preferably 5-membered or 6-membered rings.

[0195] The group formed by the bonding of any two or more of R1c to R5c, R6c and R7c, and Rx and Ry can be alkyl groups such as butylyl and pentylyl. The methylene group in the alkyl group may be substituted with a heteroatom such as an oxygen atom. The group formed by the bonding of R5c and R6c, and R5c and Rx, is preferably a single bond or an alkyl group. The alkyl group can be methylene and ethylyl.

[0196] R1c~R5c, R6c, R7c, Rx, Ry, and any two or more of R1c~R5c, R5c and R6c, R6c and R7c, R5c and Rx, and Rx and Ry may also have substituents.

[0197] Next, the cation (ZaI-4b) will be explained. The cation (ZaI-4b) is the cation represented by the following formula (ZaI-4b).

[0198] [Chemistry 42]

[0199] In formula (ZaI-4b), l represents an integer from 0 to 2. r represents an integer from 0 to 8. R13 represents a hydrogen atom, a halogen atom (e.g., fluorine and iodine atoms), a hydroxyl group, an alkyl group, a haloalkyl group, an alkoxy group, a carboxyl group, an alkoxycarbonyl group, or a group containing a cycloalkyl group (which may be the cycloalkyl group itself or a group containing a cycloalkyl group). These groups may also have substituents. R14 represents a hydroxyl group, a halogen atom (e.g., fluorine and iodine atoms), an alkyl group, a haloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, a cycloalkylsulfonyl group, or a group containing a cycloalkyl group (which may be the cycloalkyl group itself or a group containing a cycloalkyl group). These groups may also have substituents. When multiple R14s are present, each independently represents a hydroxyl group or the other such group. R15 each independently represents an alkyl group, a cycloalkyl group, or a naphthyl group. Two R15s may be bonded together to form a ring. When two R15 atoms are bonded together to form a ring, the ring skeleton may also contain heteroatoms such as oxygen or nitrogen atoms. In a single-state sample, it is preferable that the two R15 atoms are alkyl groups and are bonded together to form a ring structure. Furthermore, the alkyl group, the cycloalkyl group, the naphthyl group, and the ring formed by the two R15 atoms may also have substituents. In formula (ZaI-4b), the alkyl groups of R13, R14, and R15 can be straight-chain or branched-chain. The alkyl groups preferably have 1 to 10 carbon atoms. The alkyl groups are preferably methyl, ethyl, n-butyl, or tributyl, etc. Furthermore, each substituent in R13 to R15, as well as Rx and Ry, is preferably an acid-decomposing group formed independently by any combination of substituents.

[0201] Next, formula (ZaII) will be explained. In formula (ZaII), R204 and R205 independently represent aryl, alkyl, or cycloalkyl groups, respectively. The aryl group of R204 and R205 is preferably phenyl or naphthyl, and more preferably phenyl. The aryl group of R204 and R205 may also be an aryl group containing a heterocycle having an oxygen atom, nitrogen atom, or sulfur atom. Examples of heterocyclic aryl groups include: pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene. The alkyl and cycloalkyl groups of R204 and R205 are preferably straight-chain alkyl groups having 1 to 10 carbon atoms or branched-chain alkyl groups having 3 to 10 carbon atoms (e.g., methyl, ethyl, propyl, butyl, or pentyl), or cycloalkyl groups having 3 to 10 carbon atoms (e.g., cyclopentyl, cyclohexyl, or norbornyl).

[0202] The aryl, alkyl, and cycloalkyl groups of R204 and R205 may each independently have substituents. Examples of substituents that may be present in the aryl, alkyl, and cycloalkyl groups of R204 and R205 include: alkyl groups (e.g., 1-15 carbon atoms), cycloalkyl groups (e.g., 3-15 carbon atoms), aryl groups (e.g., 6-15 carbon atoms), alkoxy groups (e.g., 1-15 carbon atoms), halogen atoms, hydroxyl groups, and phenylthio groups. Furthermore, the substituents in R204 and R205 are preferably acid-degradable groups formed independently by any combination of substituents.

[0203] Specific examples of organic cations are shown below, but the present invention is not limited thereto.

[0204] [Chemistry 43]

[0205] [Chemical 44]

[0206] [Chemistry 45]

[0207] In the compound represented by "M+X-", X- represents an organic anion. There are no particular limitations on the organic anion, and examples include monovalent or divalent or higher organic anions. Preferably, the organic anion is an anion with a significantly low ability to induce nucleophilic reactions, and more preferably, a non-nucleophilic anion.

[0208] As non-nucleophilic anions, examples include: sulfonate anions (aliphatic sulfonate anions, aromatic sulfonate anions, and camphor sulfonate anions, etc.), carboxylate anions (aliphatic carboxylate anions, aromatic carboxylate anions, and aralkyl carboxylate anions, etc.), sulfenimine anions, bis(alkylsulfenyl)imine anions, and tri(alkylsulfenyl)methyl anions.

[0209] The aliphatic portion of the aliphatic sulfonate anion and the aliphatic carboxylate anion may be a straight-chain or branched-chain alkyl group, or a cycloalkyl group, preferably a straight-chain or branched-chain alkyl group having 1 to 30 carbon atoms, or a cycloalkyl group having 3 to 30 carbon atoms. The alkyl group may also be, for example, a fluoroalkyl group (which may have substituents other than fluorine atoms. It may also be a perfluoroalkyl group).

[0210] The aryl group in the aromatic sulfonate anion and the aromatic carboxylate anion is preferably an aryl group with 6 to 14 carbon atoms, for example: phenyl, tolyl and naphthyl.

[0211] The listed alkyl, cycloalkyl, and aryl groups may also have substituents. There are no particular limitations on the substituents; examples include: nitro, halogen atoms such as fluorine and chlorine atoms, carboxyl, hydroxyl, amino, cyano, alkoxy (preferably 1-15 carbon atoms), alkyl (preferably 1-10 carbon atoms), cycloalkyl (preferably 3-15 carbon atoms), aryl (preferably 6-14 carbon atoms), alkoxycarbonyl (preferably 2-7 carbon atoms), acetyl (preferably 2-12 carbon atoms), alkoxycarbonyloxy (preferably 2-7 carbon atoms), alkylthio (preferably 1-15 carbon atoms), alkylsulfonyl (preferably 1-15 carbon atoms), alkyliminosulfonyl (preferably 1-15 carbon atoms), and aryloxysulfonyl (preferably 6-20 carbon atoms).

[0212] The aralkyl group in the aralkyl carboxylate anion is preferably an aralkyl group having 7 to 14 carbon atoms. Examples of aralkyl groups having 7 to 14 carbon atoms include benzyl, phenethyl, naphthylmethyl, naphthylethyl, and naphthylbutyl.

[0213] As a sulfonylimidimine anion, saccharin anion can be cited as an example.

[0214] The alkyl group in the bis(alkylsulfonyl)imine anion and the tri(alkylsulfonyl)methyl anion is preferably an alkyl group having 1 to 5 carbon atoms. Examples of substituents for these alkyl groups include: halogen atoms, alkyl groups substituted with halogen atoms, alkoxy groups, alkylthio groups, alkyloxysulfonyl groups, aryloxysulfonyl groups, and cycloalkylaryloxysulfonyl groups; fluorine atoms or alkyl groups substituted with fluorine atoms are preferred. Furthermore, the alkyl groups in the bis(alkylsulfonyl)imine anion can also bond to each other to form a ring structure. This increases the acid strength.

[0215] Other nonnucleophilic anions include, for example, phosphorus fluoride (e.g., PF6-), boron fluoride (e.g., BF4-) and antimony fluoride (e.g., SbF6-).

[0216] As a non-nucleophilic anion, it is preferably an aliphatic sulfonate anion with at least α-fluorine atom substitution, an aromatic sulfonate anion with fluorine atom substitution or a fluorine-containing alkyl group substitution, an alkyl-fluorine-substituted bis(alkylsulfonyl)imidion anion, or an alkyl-fluorine-substituted tri(alkylsulfonyl)methylation anion. More preferably, it is a perfluoroaliphatic sulfonate anion (preferably having 4 to 8 carbon atoms), or a benzenesulfonate anion with a fluorine atom, and even more preferably, a nonafluorobutanesulfonate anion, a perfluorooctanesulfonate anion, a pentafluorobenzenesulfonate anion, or a 3,5-bis(trifluoromethyl)benzenesulfonate anion.

[0217] The non-nucleophilic anion is preferably the anion represented by the following formula (AN1).

[0218] [Chemistry 46]

[0219] In formula (AN1), R1 and R2 independently represent a hydrogen atom or a substituent, respectively. There are no particular limitations on the substituent, but it is preferred to be a non-electron-withdrawing group. Examples of non-electron-withdrawing groups include: hydrocarbon groups, hydroxyl groups, oxyhydrocarbonyl groups, oxycarbonyl hydrocarbon groups, amino groups, hydrocarbon-substituted amino groups, and hydrocarbon-substituted amide groups. Furthermore, it is preferred that non-electron-withdrawing groups be independently -R', -OH, -OR', -OCOR', -NH2, -NR'2, -NHR', or -NHCOR'. R' is a monovalent hydrocarbon group.

[0220] Examples of monovalent hydrocarbon groups represented by R' include: alkyl groups such as methyl, ethyl, propyl, and butyl; alkenyl groups such as vinyl, propynyl, and butenyl; alkynyl groups such as ethynyl, propynyl, and butynyl; cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, norbornyl, and adamantyl; cycloalkenyl groups such as cyclopropenyl, cyclobutenyl, cyclopentenyl, and norbornyl; aryl groups such as phenyl, tolyl, xylyl, mesitylelel, naphthyl, methylnaphthyl, anthracenel, and methylanthrayl; and aralkyl groups such as benzyl, phenethyl, phenylpropyl, naphthylmethyl, and anthracenemethyl. Preferably, R1 and R2 are independently hydrocarbon groups (preferably cycloalkyl) or hydrogen atoms.

[0221] L represents a divalent linker. When multiple Ls are present, the Ls may be the same or different. Examples of divalent linkers include: -O-CO-O-, -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 linkers formed by combining multiple of these. Among them, the divalent linker is preferably -O-CO-O-, -COO-, -CONH-, -CO-, -O-, -SO2-, -O-CO-O-extrinyl-, -COO-extrinyl-, or -CONH-extrinyl-, more preferably -O-CO-O-, -O-CO-O-extrinyl-, -COO-, -CONH-, -SO2-, or -COO-extrinyl-.

[0222] L is preferably a base represented by, for example, the following formula (AN1-1): *a-(CR2a2)XQ-(CR2b2)Y-*b(AN1-1)

[0223] In formula (AN1-1), *a represents the bond position with R3 in formula (AN1). *b represents the bond position with -C(R1)(R2)- in formula (AN1). X and Y independently represent integers from 0 to 10, preferably integers from 0 to 3. R2a and R2b independently represent hydrogen atoms or substituents. When multiple R2a and R2b exist, the multiple R2a and R2b can be the same or different. Wherein, when Y is 1 or more, R2b in CR2b2 directly bonded to -C(R1)(R2)- in formula (AN1) is other than a fluorine atom. Q represents *AO-CO-O-*B, *A-CO-*B, *A-CO-O-*B, *AO-CO-*B, *AO-*B, *AS-*B, or *A-SO2-*B. In formula (AN1-1), where X+Y is 1 or more and either R2a or R2b in formula (AN1-1) is a hydrogen atom, Q represents *AO-CO-O-*B, *A-CO-*B, *AO-CO-*B, *AO-*B, *AS-*B, or *A-SO2-*B. *A represents the bond position on the R3 side in formula (AN1), and *B represents the bond position on the -SO3- side in formula (AN1).

[0224] In formula (AN1), R3 represents an organic group. The organic group is not particularly limited as long as it has one or more carbon atoms; it can be a straight-chain group (e.g., a straight-chain alkyl group), a branched-chain group (e.g., a branched-chain alkyl group such as tert-butyl), or a cyclic group. The organic group may or may not have substituents. The organic group may or may not have heteroatoms (oxygen atoms, sulfur atoms, and / or nitrogen atoms, etc.).

[0225] Wherein, R3 is preferably an organogroup with a cyclic structure. The cyclic structure can be monocyclic or polycyclic, and may also have substituents. The ring in the organogroup containing the cyclic structure is preferably directly bonded to L in formula (AN1). The organogroup with the cyclic structure may have heteroatoms (oxygen atom, sulfur atom, and / or nitrogen atom, etc.), or may not have them. The heteroatoms may be substituted with one or more carbon atoms forming the cyclic structure. The organogroup with the cyclic structure is preferably, for example, a cyclic hydrocarbon group, a lactone cyclic group, or a sulfonyl lactone cyclic group. Wherein, the organogroup with the cyclic structure is preferably a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a monocyclic or polycyclic cycloalkyl group. These groups may also have substituents. The cycloalkyl group may be monocyclic (cyclohexyl, etc.) or polycyclic (adamantyl, etc.), and the number of carbon atoms is preferably 5 to 12. The lactone group and sulfonolactone group are preferably formed by removing a hydrogen atom from the ring member atom constituting the lactone structure or sulfonolactone structure, for example, any of the structures represented by formulas (LC1-1) to (LC1-21) and formulas (SL1-1) to (SL1-3).

[0226] As a non-nucleophilic anion, it can be a benzenesulfonate anion, preferably a benzenesulfonate anion substituted with a branched chain of alkyl or cycloalkyl groups.

[0227] The non-nucleophilic anion is preferably the anion represented by the following formula (AN2).

[0228] [Chemistry 47] In equation (AN2)

[0229] , o represents an integer from 1 to 3. p represents an integer from 0 to 10. q represents an integer from 0 to 10.

[0230] Xf represents a hydrogen atom, a fluorine atom, an alkyl group formed by substitution with at least one fluorine atom, or an organogroup without a fluorine atom. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 4. Furthermore, as an alkyl group formed by substitution with at least one fluorine atom, a perfluoroalkyl group is preferred. Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms, more preferably a fluorine atom or CF3, and even more preferably both Xf atoms are fluorine atoms.

[0231] 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. In the presence of multiple R4 and R5 groups, R4 and R5 may be the same or different. The alkyl group represented by R4 and R5 preferably has 1 to 4 carbon atoms. The alkyl group may have substituents. Hydrogen atoms are preferred as R4 and R5.

[0232] L represents a binary linkage base. The definition of L is the same as that of L in equation (AN1).

[0233] W represents an organic group containing a cyclic structure. Preferably, it is a cyclic organic group. Examples of cyclic organic groups include alicyclic, aryl, and heterocyclic groups. The alicyclic group can be monocyclic or polycyclic. Examples of monocyclic alicyclic groups include cyclopentyl, cyclohexyl, and cyclooctyl monocyclic cycloalkyl groups. Examples of polycyclic alicyclic groups include norbornyl, tricyclic decyl, tetracyclic decyl, tetracyclic dodecyl, and adamantyl polycyclic cycloalkyl groups. Preferably, it is an alicyclic group with a large volume structure having 7 or more carbon atoms, such as norbornyl, tricyclic decyl, tetracyclic decyl, tetracyclic dodecyl, and adamantyl.

[0234] The aryl group can be monocyclic or polycyclic. Examples of the aryl group include phenyl, naphthyl, phenanthryl, and anthracene. The heterocyclic group can be monocyclic or polycyclic. In the case of a polycyclic heterocyclic group, the diffusion of acid can be further suppressed. In addition, the heterocyclic group may or may not be aromatic. Examples of aromatic heterocycles include furan ring, thiophene ring, benzofuran ring, benzothiophene ring, dibenzofuran ring, dibenzothiophene ring, and pyridine ring. Examples of non-aromatic heterocycles include tetrahydropyran ring, lactone ring, sulfonyl lactone ring, and decahydroisoquinoline ring. The heterocycle in the heterocyclic group is preferably a furan ring, thiophene ring, pyridine ring, or decahydroisoquinoline ring.

[0235] The cyclic organic group may also have substituents. Examples of such substituents include: alkyl groups (which may be either straight-chain or branched-chain, preferably with 1 to 12 carbon atoms), cycloalkyl groups (which may be either monocyclic, polycyclic, or spirocyclic, preferably with 3 to 20 carbon atoms), aryl groups (preferably with 6 to 14 carbon atoms), hydroxyl groups, alkoxy groups, ester groups, amide groups, carbamate groups, urea groups, thioether groups, sulfonamide groups, and sulfonate groups. Furthermore, the carbon atoms constituting the cyclic organic group (carbons that contribute to ring formation) may also be carbonyl carbons.

[0236] The anion represented by formula (AN1) is preferably 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. Here, L, q, and W are the same as in formula (AN2). q' represents an integer from 0 to 10.

[0237] As a non-nucleophilic anion, it is also preferred to be an aromatic sulfonate anion represented by the following formula (AN3).

[0238] [Chemistry 48]

[0239] In formula (AN3), Ar represents an aryl group (phenyl, etc.), and may also have substituents other than a sulfonate anion and a -(DB) group. Examples of substituents that may be added include fluorine atoms and hydroxyl groups. n represents an integer greater than or equal to 0. Preferably, n is 1 to 4, more preferably 2 to 3, and even more preferably 3.

[0240] D represents a single bond or a divalent linker. Examples of divalent linkers include: ether groups, thioether groups, carbonyl groups, ternary groups, ternary groups, sulfonate groups, ester groups, and groups containing two or more of these.

[0241] B represents a hydrocarbon group. Preferably, B is an aliphatic hydrocarbon group, more preferably isopropyl, cyclohexyl, or an aryl group (such as tricyclohexylphenyl, etc.) that may have more substituents.

[0242] As a non-nucleophilic anion, a disulfonamide anion is preferred. The disulfonamide anion is, for example, an anion represented by N-(SO2-Rq)2. Here, Rq represents an alkyl group that may have substituents, preferably a fluoroalkyl group, and more preferably a perfluoroalkyl group. Two Rq groups may bond together to form a ring. The group formed by the bonding of two Rq groups is preferably a substituent-containing alkyl group, more preferably a fluoroalkyl group, and even more preferably a perfluoroalkyl group. The alkyl group preferably has 2 to 4 carbon atoms.

[0243] In addition, as non-nucleophilic anions, anions represented by the following formulas (d1-1) to (d1-4) can also be listed.

[0244] [Chemistry 49]

[0245] [Chemical 50]

[0246] In formula (d1-1), R51 represents a hydrocarbon group (e.g., aryl group such as phenyl) that may have substituents (e.g., hydroxyl groups).

[0247] In formula (d1-2), Z2c represents a hydrocarbon group with 1 to 30 carbon atoms that may have substituents (wherein the carbon atom adjacent to S is not substituted with a fluorine atom). The hydrocarbon group in Z2c may be linear, branched, or have a cyclic structure. In addition, the carbon atom in the hydrocarbon group (preferably a carbon atom that is a ring member when the hydrocarbon group has a cyclic structure) may also be a carbonyl carbon (-CO-). As such a hydrocarbon group, a group containing norbornyl that may have substituents can be listed, for example. The carbon atom forming the norbornyl group may be a carbonyl carbon. In addition, "Z2c-SO3-" in formula (d1-2) is preferably different from the anion represented by formulas (AN1) to (AN3). For example, Z2c is preferably a group other than an aryl group. In addition, for example, the atoms at the α and β positions relative to -SO3- in Z2c are preferably atoms other than carbon atoms with a fluorine atom as a substituent. For example, Z2c is preferably a ring member atom in a cyclic group, where the atom at the α-position relative to -SO3- and / or the atom at the β-position is a ring member atom in a cyclic group.

[0248] In formula (d1-3), R52 represents an organic group (preferably a hydrocarbon group with fluorine atoms), Y3 represents a linear, branched, or cyclic alkyl, aryl, or carbonyl group, and Rf represents a hydrocarbon group.

[0249] In formula (d1-4), R53 and R54 independently represent organic groups (preferably hydrocarbon groups with fluorine atoms). R53 and R54 can bond to each other to form a ring.

[0250] Organic anions can be used alone or in combination with two or more.

[0251] The acid generating agent is preferably selected from at least one of the group consisting of compounds (I) to (II).

[0252] (Compound (I)) Compound (I) is a compound having one or more structural sites X and one or more structural sites Y and producing an acid upon irradiation with an electron beam, wherein the acid comprises a first acidic site derived from structural site X and a second acidic site derived from structural site Y. Structural site X: A structural site comprising an anionic site Al- and a cation site M1+ and forming a first acidic site represented by HA1 upon irradiation with an electron beam. Structural site Y: A structural site comprising an anionic site A2- and a cation site M2+ and forming a second acidic site represented by HA2 upon irradiation with an electron beam. The cation represented by at least one of the cation sites M1+ in the more than one structural site X and M2+ in the more than one structural site Y is represented by at least one cation represented by formula (X). Furthermore, compound (I) satisfies the following condition I.

[0253] Condition I: In the compound (I), the compound PI formed by replacing the cation M1+ in the structural site X and the cation M2+ in the structural site Y with H+ has an acid dissociation constant a1 and an acid dissociation constant a2. The acid dissociation constant a1 originates from the acidic site represented by HA1, which is formed by replacing the cation M1+ in the structural site X with H+. The acid dissociation constant a2 originates from the acidic site represented by HA2, which is formed by replacing the cation M2+ in the structural site Y with H+. The acid dissociation constant a2 is greater than the acid dissociation constant a1.

[0254] Hereinafter, condition I will be explained in more detail. When compound (I) is, for example, a compound that produces an acid having a first acidic site derived from the structural site X and a second acidic site derived from the structural site Y, compound PI is equivalent to "a compound having HA1 and HA2". More specifically, the acid dissociation constants a1 and a2 of such compound PI are, when the acid dissociation constants of compound PI are determined, the pKa of compound PI when it is "a compound having A1- and HA2" is the acid dissociation constant a1, and the pKa of "a compound having A1- and HA2" when it is "a compound having A1- and A2-" is the acid dissociation constant a2.

[0255] Furthermore, when compound (I) is, for example, a compound that produces an acid having two first acidic sites originating from the structural site X and one second acidic site originating from the structural site Y, compound PI is equivalent to "a compound having two HA1 and one HA2". When the acid dissociation constant of such compound PI is determined, the acid dissociation constant when compound PI is "a compound having one A1- and one HA1 and one HA2", and the acid dissociation constant when "a compound having one A1- and one HA1 and one HA2" is "a compound having two A1- and one HA2", are equivalent to the acid dissociation constant a1. Additionally, the acid dissociation constant when "a compound having two A1- and one HA2" is "a compound having two A1- and A2-" is equivalent to the acid dissociation constant a2. That is, in this compound PI, when there are multiple acid dissociation constants representing acidic sites derived from replacing the cation site M1+ in the structural site X with H+, the value of acid dissociation constant a2 is greater than the largest value among the multiple acid dissociation constants a1. Furthermore, when the acid dissociation constant of compound PI is defined as "a compound having one A1-, one HA1, and one HA2", and the acid dissociation constant of "a compound having one A1-, one HA1, and one HA2" is defined as "a compound having two A1- and one HA2", the relationship between aa and ab satisfies aa < ab.

[0256] The acid dissociation constants a1 and a2 are determined by the method for determining the acid dissociation constant. The compound PI corresponds to the acid produced when compound (I) is irradiated with an electron beam. When compound (I) has two or more structural sites X, the structural sites X may be the same or different. In addition, the two or more A1- and the two or more M1+ may be the same or different. Furthermore, the A1- and A2-, as well as the M1+ and M2+ in compound (I) may be the same or different, and it is preferable that A1- and A2- are different.

[0257] In the compound PI, the difference (absolute value) between the acid dissociation constant a1 (which is the maximum value when multiple acid dissociation constants a1 exist) and the acid dissociation constant a2 is preferably 0.1 or more, more preferably 0.5 or more, and even more preferably 1.0 or more. Furthermore, there is no particular limitation on the upper limit of the difference (absolute value) between the acid dissociation constant a1 (which is the maximum value when multiple acid dissociation constants a1 exist) and the acid dissociation constant a2, for example, it is 16 or less.

[0258] In the compound PI, the acid dissociation constant a2 is preferably 20 or less, more preferably 15 or less. Furthermore, as a lower limit value of the acid dissociation constant a2, it is preferably -4.0 or more.

[0259] Furthermore, in the compound PI, the acid dissociation constant a1 is preferably 2.0 or less, more preferably 0 or less. Moreover, as a lower limit value of the acid dissociation constant a1, it is preferably -20.0 or more.

[0260] The anionic sites A1- and A2- are structural sites containing negatively charged atoms or groups of atoms. For example, structural sites selected from the group consisting of formulas (AA-1) to (AA-3) and (BB-1) to (BB-6) shown below can be included. As an anionic site A1-, it is preferable to form an acidic site with a small acid dissociation constant, more preferably any one of formulas (AA-1) to (AA-3), and even more preferably any one of formulas (AA-1) and (AA-3). In addition, as an anionic site A2-, it is preferable to form an acidic site with a larger acid dissociation constant than anionic site A1-, more preferably any one of formulas (BB-1) to (BB-6), and even more preferably any one of formulas (BB-1) and (BB-4). Furthermore, in the following formulas (AA-1) to (AA-3) and (BB-1) to (BB-6), * indicates the bond position. In formula (AA-2), RA represents a monovalent organic group. There are no particular limitations on the monovalent organic group represented by RA; for example, cyano, trifluoromethyl, and methanesulfonyl can be listed.

[0261] [Chemistry 51]

[0262] Furthermore, the cation sites M1+ and M2+ are structural sites containing positively charged atoms or groups of atoms, such as monovalent organic cations. Moreover, as organic cations, examples include the organic cation represented by M+.

[0263] There are no particular limitations on the specific structure of compound (I), for example, the compounds represented by formulas (Ia-1) to (Ia-5) described later can be listed.

[0264] -The compounds represented by formula (Ia-1)- Hereinafter, the compounds represented by formula (Ia-1) will be described first.

[0265] M11+A11--L1-A12-M12+(Ia-1)

[0266] The compound represented by formula (Ia-1) produces an acid represented by HA11-L1-A12H by irradiation with an electron beam.

[0267] In formula (Ia-1), M11+ and M12+ independently represent organic cations. A11- and A12- independently represent monovalent anionic functional groups. L1 represents a divalent linker. M11+ and M12+ may be the same or different. A11- and A12- may be the same or different, preferably different from each other. In the compound PIa (HA11-L1-A12H) formed by replacing the cations represented by M11+ and M12+ with H+ in formula (Ia-1), the acid dissociation constant a2 derived from the acidic site represented by A12H is larger than the acid dissociation constant a1 derived from the acidic site represented by HA11. Furthermore, the preferred values ​​of acid dissociation constant a1 and acid dissociation constant a2 are as described above. In addition, compound PIa is the same as the acid produced by the compound represented by formula (Ia-1) through electron beam irradiation. In addition, at least one of M11+, M12+, A11-, A12- and L1 may have an acid-degradable group as a substituent.

[0268] In formula (Ia-1), the organic cations represented by M1+ and M2+ are as described above.

[0269] The monovalent anionic functional group represented by A11- refers to a monovalent group containing the anionic site A1-. Furthermore, the monovalent anionic functional group represented by A12- refers to a monovalent group containing the anionic site A2-. Preferably, the monovalent anionic functional groups represented by A11- and A12- are monovalent anionic functional groups containing any one anionic site of formulas (AA-1) to (AA-3) and (BB-1) to (BB-6), and more preferably are monovalent anionic functional groups selected from the group consisting of formulas (AX-1) to (AX-3) and (BX-1) to (BX-7). As for the monovalent anionic functional group represented by A11-, it is preferably a monovalent anionic functional group represented by any one of formulas (AX-1) to (AX-3). Furthermore, as a monovalent anionic functional group represented by A12-, it is preferably a monovalent anionic functional group represented by any one of formulas (BX-1) to (BX-7), and more preferably a monovalent anionic functional group represented by any one of formulas (BX-1) to (BX-6).

[0270] [Chemical 52]

[0271] In formulas (AX-1) to (AX-3), RA1 and RA2 independently represent monovalent organic groups. * indicates the bonding position. There are no particular limitations on the monovalent organic group represented by RA1, such as cyano, trifluoromethyl and methanesulfonyl.

[0272] The monovalent organic group represented by RA2 is preferably a straight-chain, branched-chain, or cyclic alkyl group or an aryl group. The alkyl group preferably has 1 to 15 carbon atoms, more preferably 1 to 10, and even more preferably 1 to 6. The alkyl group may also have substituents. The substituents are preferably fluorine atoms or cyano groups, more preferably fluorine atoms. When the alkyl group has a fluorine atom as a substituent, it may be a perfluoroalkyl group.

[0273] The aryl group is preferably phenyl or naphthyl, and more preferably phenyl. The aryl group may also have substituents. The substituents are preferably fluorine atoms, iodine atoms, perfluoroalkyl groups (e.g., preferably having 1 to 10 carbon atoms, more preferably having 1 to 6 carbon atoms) or cyano groups, and more preferably fluorine atoms, iodine atoms or perfluoroalkyl groups.

[0274] In formulas (BX-1) to (BX-4) and (BX-6), RB represents a monovalent organogroup. * indicates a bond position. The monovalent organogroup represented by RB is preferably a straight-chain, branched-chain, or cyclic alkyl group, or an aryl group. The alkyl group preferably has 1 to 15 carbon atoms, more preferably 1 to 10, and even more preferably 1 to 6. The alkyl group may also have substituents. There are no particular limitations on the substituents; fluorine atoms or cyano groups are preferred, and fluorine atoms are more preferred. When the alkyl group has a fluorine atom as a substituent, it may be a perfluoroalkyl group. Furthermore, when the carbon atom at the bonding position in the alkyl group (for example, in formulas (BX-1) and (BX-4), it corresponds to the carbon atom in the alkyl group directly bonded to the -CO- group explicitly stated in the formula; in formulas (BX-2) and (BX-3), it corresponds to the carbon atom in the alkyl group directly bonded to the -SO2- group explicitly stated in the formula; and in formula (BX-6), it corresponds to the carbon atom in the alkyl group directly bonded to the N- group explicitly stated in the formula) has a substituent, it is preferably a substituent other than a fluorine atom or a cyano group. Additionally, the carbon atom in the alkyl group may be substituted with a carbonyl carbon.

[0275] The aryl group is preferably phenyl or naphthyl, more preferably phenyl. The aryl group may also have substituents. The substituents are preferably fluorine atoms, iodine atoms, perfluoroalkyl (e.g., preferably having 1 to 10 carbon atoms, more preferably having 1 to 6 carbon atoms), cyano, alkyl (e.g., preferably having 1 to 10 carbon atoms, more preferably having 1 to 6 carbon atoms), alkoxy (e.g., preferably having 1 to 10 carbon atoms, more preferably having 1 to 6 carbon atoms) or alkoxycarbonyl (e.g., preferably having 2 to 10 carbon atoms, more preferably having 2 to 6 carbon atoms), and more preferably fluorine atoms, iodine atoms, perfluoroalkyl, alkyl, alkoxy, or alkoxycarbonyl.

[0276] In formula (Ia-1), the divalent linker represented by L1 is not particularly limited and can be listed as: -CO-, -NR-, -O-, -S-, -SO-, -SO2-, alkyl groups (preferably with 1 to 6 carbon atoms; can be straight-chain or branched-chain), cycloalkyl groups (preferably with 3 to 15 carbon atoms), alkenyl groups (preferably with 2 to 6 carbon atoms), and divalent aliphatic heterocyclic groups (preferably having at least one N atom, O atom, or S atom within the ring structure). The following are possible alternatives: 5- to 10-membered rings with a Se atom, more preferably 5- to 7-membered rings, and even more preferably 5- to 6-membered rings; divalent aromatic heterocyclic groups (preferably 5- to 10-membered rings having at least one N, O, S, or Se atom within the ring structure, more preferably 5- to 7-membered rings, and even more preferably 5- to 6-membered rings); divalent aromatic hydrocarbon cyclic groups (preferably 6- to 10-membered rings, and even more preferably 6-membered rings); and divalent linking groups formed by combining multiple of these. R can be a hydrogen atom or a monovalent organometallic group. There are no particular limitations on the monovalent organometallic group, but it is preferably, for example, an alkyl group (preferably having 1 to 6 carbon atoms). Furthermore, the alkylene group, the cycloalkyl group, the alkenyl group, the divalent aliphatic heterocyclic group, the divalent aromatic heterocyclic group, and the divalent aromatic hydrocarbon cyclic group may also have substituents. For example, halogen atoms (preferably fluorine atoms) can be listed as substituents.

[0277] In this context, the binary linking base represented by L1 is preferably the binary linking base represented by equation (L1).

[0278] [Chemical 53]

[0279] In formula (L1), L111 represents a single bond or a divalent linker. There are no particular limitations on the divalent linker represented by L111, and examples include: -CO-, -NH-, -O-, -SO-, -SO2-, alkyl groups with substituents (preferably 1 to 6 carbon atoms, which can be either straight-chain or branched-chain), cycloalkyl groups with substituents (preferably 3 to 15 carbon atoms), aryl groups with substituents (preferably 6 to 10 carbon atoms), and divalent linkers formed by combining multiple of these. There are no particular limitations on the substituents, and examples include halogen atoms. p represents an integer from 0 to 3, preferably an integer from 1 to 3. v represents an integer of 0 or 1. Xf1 independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 4. Furthermore, as an alkyl group substituted with at least one fluorine atom, a perfluoroalkyl group is preferred. Xf2 independently represents a hydrogen atom, an alkyl group that may have a fluorine atom as a substituent, or a fluorine atom. The carbon number of the alkyl group is preferably 1 to 10, more preferably 1 to 4. Among them, Xf2 is preferably a fluorine atom, or an alkyl group substituted with at least one fluorine atom, more preferably a fluorine atom, or a perfluoroalkyl group. Among them, Xf1 and Xf2 are preferably either fluorine atoms or perfluoroalkyl groups having 1 to 4 carbon atoms, more preferably fluorine atoms or CF3. In particular, it is even more preferably that both Xf1 and Xf2 are fluorine atoms. * indicates the bonding position. When L11 in formula (Ia-1) represents the divalent linker represented by formula (L1), it is preferred that the bonding bond (*) on the L111 side of formula (L1) is bonded to A12- in formula (Ia-1).

[0280] -Compounds represented by formulas (Ia-2) to (Ia-4)- Next, the compounds represented by formulas (Ia-2) to (Ia-4) will be explained.

[0281] [Chemical 54]

[0282] In formula (Ia-2), A21a- and A21b- each independently represent a monovalent anionic functional group. Here, the monovalent anionic functional group represented by A21a- and A21b- refers to a monovalent group containing the anionic site A1-. There is no particular limitation on the monovalent anionic functional group represented by A21a- and A21b-, and for example, monovalent anionic functional groups selected from the group consisting of formulas (AX-1) to (AX-3) can be listed. A22- represents a divalent anionic functional group. Here, the divalent anionic functional group represented by A22- refers to a divalent group containing the anionic site A2-. For example, the divalent anionic functional groups represented by formulas (BX-8) to (BX-11) shown below can be listed as examples of divalent anionic functional groups represented by A22-.

[0283] [Chemical 55]

[0284] M21a+, M21b+, and M22+ each independently represent an organic cation. The organic cations represented by M21a+, M21b+, and M22+ have the same meaning as M1+, and the preferred state is also the same. L21 and L22 each independently represent a divalent organic group.

[0285] Furthermore, in the compound PIa-2 formed by replacing the organic cations represented by M21a+, M21b+, and M22+ with H+ in formula (Ia-2), the acid dissociation constant a2 derived from the acidic site represented by A22H is greater than the acid dissociation constant a1-1 derived from A21aH and the acid dissociation constant a1-2 derived from the acidic site represented by A21bH. Moreover, the acid dissociation constants a1-1 and a1-2 are equivalent to the acid dissociation constant a1. Furthermore, A21a- and A21b- may be the same or different from each other. Additionally, M21a+, M21b+, and M22+ may be the same or different from each other. Furthermore, at least one of M21a+, M21b+, M22+, A21a-, A21b-, L21, and L22 may have an acid-decomposing group as a substituent.

[0286] In formula (Ia-3), A31a- and A32- independently represent monovalent anionic functional groups. Furthermore, the definition of the monovalent anionic functional group represented by A31a- is the same as that of A21a- and A21b- in formula (Ia-2), and the preferred form is also the same. The monovalent anionic functional group represented by A32- refers to a monovalent group containing the anionic site A2-. There are no particular limitations on the monovalent anionic functional group represented by A32-; for example, monovalent anionic functional groups selected from the group consisting of formulas (BX-1) to (BX-7) can be listed. A31b- represents a divalent anionic functional group. Here, the divalent anionic functional group represented by A31b- refers to a divalent group containing the anionic site A1-. As a divalent anionic functional group represented by A31b-, for example, the divalent anionic functional group represented by the following formula (AX-4) can be listed.

[0287] [Chemical 56]

[0288] M31a+, M31b+, and M32+ each independently represent a monovalent organic cation. The organic cations represented by M31a+, M31b+, and M32+ have the same meaning as M1+, and the preferred state is also the same. L31 and L32 each independently represent a divalent organic group.

[0289] Furthermore, in the compound PIa-3 formed by replacing the organic cations represented by M31a+, M31b+, and M32+ with H+ in formula (Ia-3), the acid dissociation constant a2 derived from the acidic site represented by A32H is greater than the acid dissociation constant a1-3 derived from the acidic site represented by A31aH and the acid dissociation constant a1-4 derived from the acidic site represented by A31bH. Moreover, the acid dissociation constants a1-3 and a1-4 are equivalent to the acid dissociation constant a1. Furthermore, A31a- and A32- may be the same or different. Additionally, M31a+, M31b+, and M32+ may be the same or different. Furthermore, at least one of M31a+, M31b+, M32+, A31a-, A32-, L31, and L32 may have an acid-decomposing group as a substituent.

[0290] In formula (Ia-4), A41a-, A41b-, and A42- each independently represent a monovalent anionic functional group. Furthermore, the definitions of the monovalent anionic functional groups represented by A41a- and A41b- are the same as those for A21a- and A21b- in formula (Ia-2). Additionally, the definition of the monovalent anionic functional group represented by A42- is the same as that for A32- in formula (Ia-3), and the preferred state is also the same. M41a+, M41b+, and M42+ each independently represent an organic cation. L41 represents a trivalent organic group.

[0291] Furthermore, in the compound PIa-4 formed by replacing the organic cations represented by M41a+, M41b+, and M42+ with H+ in formula (Ia-4), the acid dissociation constant a2 originating from the acidic site represented by A42H is greater than the acid dissociation constants a1-5 originating from the acidic site represented by A41aH and a1-6 originating from the acidic site represented by A41bH. Moreover, the acid dissociation constants a1-5 and a1-6 are equivalent to the acid dissociation constant a1. Furthermore, A41a-, A41b-, and A42- can be the same or different. Additionally, M41a+, M41b+, and M42+ can be the same or different. In addition, at least one of M41a+, M41b+, M42+, A41a-, A41b-, A42- and L41 may have an acid-degradable group as a substituent.

[0292] The divalent organic groups represented by L21 and L22 in formula (Ia-2) and L31 and L32 in formula (Ia-3) are not particularly limited, and examples include: -CO-, -NR-, -O-, -S-, -SO-, -SO2-, alkyl groups (preferably with 1 to 6 carbons, which can be straight-chain or branched-chain), cycloalkyl groups (preferably with 3 to 15 carbons), alkenyl groups (preferably with 2 to 6 carbons), and divalent aliphatic heterocyclic groups (preferably having at least one carbon atom in the ring structure). The following are possible organovalent groups: a 5- to 10-membered ring (preferably 5- to 7-membered, and even more preferably 5- to 6-membered ring) containing an N, O, S, or Se atom; a divalent aromatic heterocyclic group (preferably a 5- to 10-membered ring having at least one N, O, S, or Se atom within the ring structure, more preferably 5- to 7-membered, and even more preferably 5- to 6-membered ring); a divalent aromatic hydrocarbon cyclic group (preferably a 6- to 10-membered ring, and even more preferably a 6-membered ring); and a divalent organovalent group composed of multiple combinations thereof. R can be a hydrogen atom or a monovalent organovalent group. There are no particular limitations on the monovalent organovalent group, but it is preferably, for example, an alkyl group (preferably having 1 to 6 carbon atoms). Furthermore, the alkylene group, the cycloalkylene group, the alkenyl group, the divalent aliphatic heterocyclic group, the divalent aromatic heterocyclic group, and the divalent aromatic hydrocarbon cyclic group may also have substituents. Substituents include, for example, halogen atoms (preferably fluorine atoms).

[0293] The divalent organic groups represented by L21 and L22 in formula (Ia-2) and L31 and L32 in formula (Ia-3) are preferably, for example, the divalent organic groups represented by the following formula (L2).

[0294] [Chemical 57]

[0295] In formula (L2), q represents an integer from 1 to 3. * indicates a bond position. Xf independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 4. Furthermore, as an alkyl group substituted with at least one fluorine atom, a perfluoroalkyl group is preferred. Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms, more preferably a fluorine atom or CF3. In particular, it is even more preferable that both Xf are fluorine atoms.

[0296] LA represents a single bond or a divalent linkage. There are no particular limitations on the divalent linkage represented by LA; examples include: -CO-, -O-, -SO-, -SO2-, alkyl groups (preferably with 1 to 6 carbon atoms; can be straight-chain or branched-chain), cycloalkyl groups (preferably with 3 to 15 carbon atoms), divalent aromatic hydrocarbon cycloalloys (preferably 6-membered to 10-membered rings, and more preferably 6-membered rings), and divalent linkages formed by combining multiple of these. Furthermore, the alkyl groups, cycloalkyl groups, and divalent aromatic hydrocarbon cycloalloys may also have substituents. Examples of substituents include halogen atoms (preferably fluorine atoms).

[0297] Examples of divalent organic groups represented by formula (L2) include: *-CF2-*, *-CF2-CF2-*, *-CF2-CF2-CF2-*, *-Ph-O-SO2-CF2-*, *-Ph-O-SO2-CF2-CF2-*, *-Ph-O-SO2-CF2-CF2-*, and *-Ph-OCO-CF2-*. Furthermore, *Ph* is a phenyl group that may have substituents, preferably 1,4-phenyl. There are no particular limitations on the substituents, but alkyl groups (e.g., preferably having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms), alkoxy groups (e.g., preferably having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms), or alkoxycarbonyl groups (e.g., preferably having 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms). When L21 and L22 in formula (Ia-2) represent the divalent organogroup represented by formula (L2), it is preferable that the LA-side bond (*) in formula (L2) is bonded to A21a- and A21b- in formula (Ia-2). Furthermore, when L31 and L32 in formula (Ia-3) represent the divalent organogroup represented by formula (L2), it is preferable that the LA-side bond (*) in formula (L2) is bonded to A31a- and A32- in formula (Ia-3).

[0298] -The compound represented by formula (Ia-5)- Next, formula (Ia-5) will be explained.

[0299] [Chemical 58]

[0300] In formula (Ia-5), A51a-, A51b-, and A51c- each independently represent a monovalent anionic functional group. Here, the monovalent anionic functional group represented by A51a-, A51b-, and A51c- refers to a monovalent group containing the anionic site A1-. There is no particular limitation on the monovalent anionic functional groups represented by A51a-, A51b-, and A51c-, for example, monovalent anionic functional groups selected from the group consisting of formulas (AX-1) to (AX-3) can be listed. A52a- and A52b- represent divalent anionic functional groups. Here, the divalent anionic functional groups represented by A52a- and A52b- refer to divalent groups containing the anionic site A2-. As a divalent anionic functional group represented by A22-, examples include divalent anionic functional groups selected from the group consisting of formulas (BX-8) to (BX-11).

[0301] M51a+, M51b+, M51c+, M52a+, and M52b+ each independently represent an organic cation. The organic cations represented by M51a+, M51b+, M51c+, M52a+, and M52b+ have the same meaning as M1+, and the preferred state is also the same. L51 and L53 each independently represent a divalent organic group. The divalent organic groups represented by L51 and L53 have the same meaning as L21 and L22 in formula (Ia-2), and the preferred state is also the same. L52 represents a trivalent organic group. The trivalent organic group represented by L52 has the same meaning as L41 in formula (Ia-4), and the preferred state is also the same.

[0302] Furthermore, in the compound PIa-5 formed by replacing the organic cations represented by M51a+, M51b+, M51c+, M52a+, and M52b+ with H+ in formula (Ia-5), the acid dissociation constants a2-1 and a2-2 derived from the acidic site represented by A52aH are larger than the acid dissociation constants a1-1, a1-2, and a1-3 derived from the acidic site represented by A51cH. Moreover, acid dissociation constants a1-1 to a1-3 correspond to the acid dissociation constant a1, and acid dissociation constants a2-1 and a2-2 correspond to the acid dissociation constant a2. Furthermore, A51a-, A51b-, and A51c- can be the same or different from each other. Additionally, A52a- and A52b- can be the same or different from each other. Furthermore, M51a+, M51b+, M51c+, M52a+, and M52b+ can be the same or different from each other. Additionally, at least one of M51b+, M51c+, M52a+, M52b+, A51a-, A51b-, A51c-, L51, L52, and L53 can also have an acid-decomposable group as a substituent.

[0303] (Compound (II)) Compound (II) is a compound having two or more of the structural sites X and one or more of the structural sites Z described below, and which produces an acid upon irradiation with an electron beam, the acid comprising two or more first acidic sites derived from the structural sites X and the structural site Z. Structural site Z: a ​​site capable of neutralizing the nonionic nature of the acid.

[0304] In compound (II), the definitions of structural site X, A1- and M1+ are the same as those in compound (I), and the preferred state is also the same.

[0305] In the compound (II), in the compound PII formed by replacing the cation M1+ in the structural site X with H+, the preferred range of the acid dissociation constant a1 derived from the acidic site represented by HA1, formed by replacing the cation M1+ in the structural site X with H+, is the same as the acid dissociation constant a1 in the compound PI. Furthermore, if the compound (II) is, for example, a compound having two acids derived from the first acidic site of the structural site X and the structural site Z, the compound PII is equivalent to "a compound having two HA1s". When the acid dissociation constant of the compound PII is determined, the acid dissociation constant when the compound PII is "a compound having one Al- and one HA1", and the acid dissociation constant when "a compound having one Al- and one HA1" is "a compound having two Al-s", are equivalent to the acid dissociation constant a1.

[0306] The acid dissociation constant a1 is determined by the method for determining the acid dissociation constant. The compound PII corresponds to the acid produced when compound (II) is irradiated with an electron beam. Furthermore, the two or more structural sites X may be the same or different. In addition, the two or more Al- and the two or more M1+ may be the same or different.

[0307] There are no particular limitations on the nonionicity of the structural site Z, which can neutralize the acid. For example, it is preferable to include a site containing a functional group that has a group or electrons that can interact electrostatically with a proton. Examples of functional groups that have a macrocyclic structure such as cyclic polyethers, or functional groups containing nitrogen atoms with non-covalent electron pairs that do not contribute to π-conjugation, are examples of functional groups that have a macrocyclic structure such as cyclic polyethers. A nitrogen atom with non-covalent electron pairs that do not contribute to π-conjugation is, for example, a nitrogen atom with a partial structure shown in the following formula.

[0308] [Chemical 59]

[0309] Examples of partial structures having a functional group or electron that can interact electrostatically with a proton include: crown ether structure, aza crown ether structure, primary amine structure to tertiary amine structure, pyridine structure, imidazole structure and pyrazine structure, with primary amine structure to tertiary amine structure being preferred.

[0310] There are no particular limitations on the compound (II), for example, compounds represented by the following formula (IIa-1) and the following formula (IIa-2) can be listed.

[0311] [Chemistry 60]

[0312] In formula (IIa-1), A61a- and A61b- have the same meaning as A11- in formula (Ia-1), and the preferred state is also the same. Additionally, M61a+ and M61b+ have the same meaning as M11+ in formula (Ia-1), and the preferred state is also the same. In formula (IIa-1), L61 and L62 have the same meaning as L1 in formula (Ia-1), and the preferred state is also the same.

[0313] In formula (IIa-1), R2X represents a monovalent organogroup. There are no particular limitations on the monovalent organogroup represented by R2X; examples include: -CH2- may be substituted by one or more combinations of alkyl groups (preferably with 1 to 10 carbon atoms, and may be straight-chain or branched-chain), cycloalkyl groups (preferably with 3 to 15 carbon atoms), or alkenyl groups (preferably with 2 to 6 carbon atoms) selected from the group consisting of -CO-, -NH-, -O-, -S-, -SO-, and -SO2-. Furthermore, the alkyl, cycloalkyl, and alkenyl groups may also have substituents. There are no particular limitations on the substituents; examples include halogen atoms (preferably fluorine atoms).

[0314] Furthermore, in the compound PIIa-1 formed by replacing the organic cations represented by M61a+ and M61b+ with H+ in formula (IIa-1), the acid dissociation constants a1-7 derived from the acidic site represented by A61aH and a1-8 derived from the acidic site represented by A61bH are equivalent to the acid dissociation constant a1. Moreover, in the compound PIIa-1 formed by replacing the cation sites M61a+ and M61b+ in the structural site X with H+ in formula (IIa-1), it is equivalent to HA61a-L61-N(R2X)-L62-A61bH. Additionally, compound PIIa-1 is the same acid produced by the compound represented by formula (IIa-1) through electron beam irradiation. In addition, at least one of M61a+, M61b+, A61a-, A61b-, L61, L62 and R2X may have an acid-degradable group as a substituent.

[0315] In formula (IIa-2), A71a-, A71b-, and A71c- have the same meaning as A11- in formula (Ia-1), and the preferred state is also the same. Furthermore, M71a+, M71b+, and M71c+ have the same meaning as M11+ in formula (Ia-1), and the preferred state is also the same. In formula (IIa-2), L71, L72, and L73 have the same meaning as L1 in formula (Ia-1), and the preferred state is also the same.

[0316] Furthermore, in formula (IIa-2), in the compound PIIa-2 formed by replacing the organic cations represented by M71a+, M71b+, and M71c+ with H+, the acid dissociation constant a1-9 derived from the acidic site represented by A71aH, the acid dissociation constant a1-10 derived from the acidic site represented by A71bH, and the acid dissociation constant a1-11 derived from the acidic site represented by A71cH are equivalent to the acid dissociation constant a1. Moreover, in formula (IIa-1), in the compound PIIa-2 formed by replacing the cation sites M71a+, M71b+, and M71c+ in the structural site X with H+, it is equivalent to HA71a-L71-N(L73-A71cH)-L72-A71bH. Furthermore, compound PIIa-2 is the same acid produced by the compound represented by formula (IIa-2) through electron beam irradiation. In addition, at least one of M71a+, M71b+, M71c+, A71a-, A71b-, A71c-, L71, L72 and L73 may have an acid-decomposing group as a substituent.

[0317] Examples of compounds (I) to (II) may have sites other than cations.

[0318] [Chemistry 61]

[0319] [Chemistry 62]

[0320] The following are specific examples of acid generating agents, but are not limited thereto.

[0321] [Chemistry 63]

[0322] [Chemical 64]

[0323] When the resist layer contains an acid generating agent (B), the content of the acid generating agent (B) is not particularly limited. However, in terms of further rectangularizing the cross-sectional shape of the formed pattern, it is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and even more preferably 10% by mass or more, relative to the total mass of the resist layer. Furthermore, relative to the total mass of the resist layer, the content is preferably 50.0% by mass or less, more preferably 30.0% by mass or less, and even more preferably 25.0% by mass or less. The acid generating agent (B) can be used alone or in combination with two or more agents.

[0324] (Acid Diffusion Control Agent (C)) The resist layer may also contain an acid diffusion control agent. The acid diffusion control agent functions as a quencher that captures the acid generated from the acid generator or the like during electron beam irradiation and inhibits the reaction of the acid-decomposing resin in the unirradiated area caused by excess generated acid. There are no particular limitations on the type of acid diffusion control agent, for example, basic compounds (CA), low molecular weight compounds (CB) having nitrogen atoms and having groups that are removed by the action of acid, and compounds (CC) whose acid diffusion control ability is reduced or disappears by electron beam irradiation. As compounds (CC), examples include onium salt compounds (CD) that are relatively weak acids relative to the acid generator, and basic compounds (CE) whose basicity is reduced or disappears by electron beam irradiation. The onium salt compound (CC) is an onium salt compound that generates acid by electron beam irradiation. The acid generated from the onium salt is a carboxylic acid relative to the acid generated from the acid generator, and is equivalent to the onium salt compound. Furthermore, as specific examples of basic compounds (CA), those described in paragraphs

[0132] to

[0136] of International Publication No. 2020 / 066824 can be cited; as specific examples of basic compounds (CE) whose basicity is reduced or eliminated by an electron beam can be cited in paragraphs

[0137] to

[0155] of International Publication No. 2020 / 066824; as specific examples of low molecular weight compounds (CB) having nitrogen atoms and having groups that are removed by the action of acids can be cited in paragraphs

[0156] to

[0163] of International Publication No. 2020 / 066824; and as specific examples of onium salt compounds (CE) having nitrogen atoms in the cation portion can be cited in paragraph

[0164] of International Publication No. 2020 / 066824. Furthermore, as a specific example of an onium salt compound (CD) that is a relatively weak acid relative to an acid-generating agent, the compounds described in paragraphs

[0305] to

[0314] of International Publication No. 2020 / 158337 can be cited.

[0325] In addition to the above, for example, well-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 may also be used as acid diffusion control agents.

[0326] When the resist layer contains an acid diffusion control agent, the content of the acid diffusion control agent (total if multiple agents are present) is preferably 0.1% to 15.0% by mass, more preferably 1.0% to 15.0% by mass, relative to the total mass of the resist layer. One type of acid diffusion control agent may be used alone, or two or more may be used together.

[0327] (Hydrophobic Resin (D)) The composition for forming the resist layer may further include a hydrophobic resin different from resin (A). The hydrophobic resin is preferably designed to be present on the surface of the resist film, but unlike surfactants, it does not necessarily need to have hydrophilic groups within its molecules, and may not contribute to the uniform mixing of polar and non-polar substances. Effects of adding the hydrophobic resin include controlling the static and dynamic contact angle of the resist film surface relative to water, and suppressing gas escape.

[0328] Regarding the presence of a tendency towards the film surface, the hydrophobic resin is preferably one or more of a structure having fluorine atoms, silicon atoms, and a CH3 moiety contained in the side chain portion of the resin, more preferably having two or more. Furthermore, the hydrophobic resin is preferably a hydrocarbon group having 5 or more carbon atoms. These groups may be present in the main chain of the resin or may be substituted in the side chain. Examples of hydrophobic resins include compounds described in paragraphs

[0275] to

[0279] of International Publication No. 2020 / 004306.

[0329] When the resist layer contains a hydrophobic resin, the content of the hydrophobic resin is preferably 0.01% to 20.0% by mass, and more preferably 0.1% to 15.0% by mass, relative to the total mass of the resist layer.

[0330] (Surfactant (E)) The resist layer may also contain a surfactant. If a surfactant is included, a pattern with better adhesion and fewer development defects can be formed. The surfactant is preferably a fluorine-based and / or silicon-based surfactant. Examples of fluorine-based and / or silicon-based surfactants include those disclosed in paragraphs

[0218] and

[0219] of International Publication No. 2018 / 19395. These surfactants may be used alone or in combination.

[0331] When the resist layer contains a surfactant, the surfactant content is preferably 0.0001% to 2.0% by mass, more preferably 0.0005% to 1.0% by mass, and even more preferably 0.1% to 1.0% by mass, relative to the total mass of the resist layer.

[0332] (Other Additives) The resist layer may also contain solubility-inhibiting compounds, dyes, plasticizers, photosensitizers, light absorbers, and / or compounds that promote solubility relative to the developer (e.g., phenolic compounds with a molecular weight of less than 1000, or alicyclic or aliphatic compounds containing carboxyl groups).

[0333] There are no particular limitations on the method for forming the resist layer. As described above, methods using a composition for forming the resist layer can be listed. Preferably, the composition for forming the resist layer includes the resin (A), the acid generating agent, and the solvent. Preferably, the composition for forming the resist layer further includes the acid diffusion control agent. Furthermore, the composition for forming the resist layer may also include materials other than the resin (A), the acid generating agent, and the acid diffusion control agent.

[0334] The composition for forming the resist layer preferably includes a solvent as described above. The solvent preferably includes at least one of (M1) propylene glycol monoalkyl ether carboxylate and (M2), wherein (M2) is at least one selected from the group consisting of propylene glycol monoalkyl ether, lactate, acetate, alkoxypropionate, chain ketone, cyclic ketone, lactone, and alkyl carbonate. Furthermore, the solvent may further include components other than (M1) and (M2).

[0335] The inventors have discovered that when such a solvent is used in combination with the resin, the coatability of the composition for forming the resist layer is improved, and a pattern with fewer development defects can be formed. Although the reason may not be clear, the inventors believe that the reason is that these solvents, due to the good balance of the solubility, boiling point and viscosity of the resin, can suppress uneven film 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, which are incorporated herein by reference.

[0336] In cases where the solvent further includes components other than component (M1) and component (M2), the content of components other than component (M1) and component (M2) is preferably 5% to 30% by mass relative to the total amount of solvent.

[0337] The solvent content in the composition for forming the resist layer is preferably set to a solid component concentration of 0.5% to 30% by mass, more preferably 1% to 20% by mass.

[0338] <Intermediate Layer> The intermediate layer is a layer disposed between the resist layer and the conductive layer. The intermediate layer is a layer different from either the resist layer or the conductive layer. Preferably, the intermediate layer does not contain resin (A). In addition, the intermediate layer preferably does not contain conductive polymer. Preferably, the intermediate layer contains resin (hereinafter also referred to as resin (X)). That is, the intermediate layer is preferably a resin layer containing resin (X). Furthermore, generally, the resin (X) contained in the intermediate layer is a different resin from the resin (A) contained in the resist layer. As resin (X), it is preferably a resin soluble in the developer used in the developing process. When the developer is an alkaline developer, it is preferably a resin soluble in the alkaline developer; when the developer is an organic developer, it is preferably a resin soluble in the organic developer. The term "resin soluble in developer" refers to a resin that, when coated with a composition X containing only resin (X) as a solid component, produces a resin layer with a thickness of 100 nm by baking the resulting coating at 100°C for 300 seconds, and when immersed in developer (30 ml) for 30 seconds, exhibits a film reduction of 98 nm or more. Preferably, the film reduction of the resin layer is 100 nm. Furthermore, the composition X contains, in addition to resin (X), a solvent capable of dissolving resin (X). This solvent capable of dissolving resin (X) refers to a solvent that dissolves 10 g or more of resin (X) relative to 1 L of the solvent. Moreover, resins soluble in alkaline developers and resins soluble in organic developers are generally difficult to dissolve in water. Therefore, as described below, when the composition for forming the conductive layer is an aqueous composition containing water, even if the composition for forming the conductive layer is coated on the intermediate layer, the intermediate layer is difficult to dissolve, and the desired laminate can be manufactured with good productivity.

[0339] (Resin (X)) Resin (X) may also contain repeating units having alkali-soluble groups. When resin (X) contains repeating units having alkali-soluble groups, the solubility of resin (X) in alkaline developing solution is improved. Examples of alkali-soluble groups include phenolic hydroxyl, carboxyl, fluorinated alcohol, sulfonic acid, sulfonamide, sulfonamide, (alkylsulfonyl)(alkylcarbonyl)methylene, (alkylsulfonyl)(alkylcarbonyl)imino, bis(alkylcarbonyl)methylene, bis(alkylcarbonyl)imino, bis(alkylsulfonyl)methylene, bis(alkylsulfonyl)imino, tri(alkylcarbonyl)methylene, and tri(alkylsulfonyl)methylene, with carboxyl, phenolic hydroxyl, fluorinated alcohol, sulfonic acid, or sulfonamide groups being preferred. Examples of fluorinated alcohol groups include -CF2OH, -CH2CF2OH, -CH2CF2CF2OH, -C(CF3)2OH, -CF2CF(CF3)OH, and -CH2C(CF3)2OH. Hexafluoroisopropanol is preferred as a fluorinated alcohol group.

[0340] The repeating unit having a base-soluble group is preferably the repeating unit represented by formula (A).

[0341] [Chemical 65]

[0342] Ra1 represents a hydrogen atom or an alkyl group. La represents a single bond or an n+1 valent linkage. Examples of n+1 valent linkages include divalent and trivalent linkages. More specifically, examples include: -O-CO-O-, -COO-, -CONH-, -CO-, -O-, -S-, -SO-, -SO2-, alkyl groups (preferably with 1 to 6 carbon atoms), divalent or trivalent aliphatic cycloalcohols (preferably with 3 to 15 carbon atoms), alkenyl groups (preferably with 2 to 6 carbon atoms), divalent or trivalent aromatic cycloalcohols, and divalent or trivalent linkages formed by combining multiple of these. Ra2 represents a base-soluble group. n represents an integer greater than or equal to 1. Preferably, n is 1 to 5, more preferably 1 to 2.

[0343] Examples of repeating units having an alkali-soluble group can be cited from paragraphs

[0278] to

[0287] of Japanese Patent Application Publication No. 2008-309878.

[0344] When the resin (X) contains repeating units having alkali-soluble groups, the content of repeating units having alkali-soluble groups is preferably 30 mol% to 100 mol% relative to all repeating units of the resin (X), more preferably 50 mol% to 90 mol%. The resin (X) may contain only one type of repeating unit having alkali-soluble groups, or it may contain two or more types.

[0345] The resin (X) may also contain repeating units having monocyclic or polycyclic cycloalkyl groups. Monocyclic or polycyclic cycloalkyl groups may also be contained in either the main chain or the side chain of the repeating unit. Examples of monocyclic cycloalkyl groups include cyclopentyl, cyclohexyl, and cyclooctyl. Examples of polycyclic cycloalkyl groups include norbornyl, tricyclic decyl, tetracyclic decyl, tetracyclic dodecyl, and adamantyl. The monocyclic or polycyclic cycloalkyl groups may further be substituted with substituents. Examples of substituents include hydroxyl groups.

[0346] When the resin (X) contains repeating units having monocyclic or polycyclic cycloalkyl groups, the content of repeating units having monocyclic or polycyclic cycloalkyl groups is preferably 5 mol% to 30 mol% relative to all repeating units of the resin (X), more preferably 10 mol% to 20 mol%. The resin (X) may contain only one type of repeating unit having monocyclic or polycyclic cycloalkyl groups, or it may contain two or more types.

[0347] The resin (X) may also contain repeating units having a CH3 moiety structure in the side chain portion. Furthermore, the resin (X) may also contain repeating units having at least two CH3 moiety structures in the side chain portion, or repeating units having at least three CH3 moiety structures in the side chain portion. Here, the CH3 moiety structure in the side chain portion of the resin (X) includes the CH3 moiety structures of ethyl and propyl groups, etc. On the other hand, methyl groups directly bonded to the main chain of the resin (X) (e.g., α-methyl groups of repeating units having a methacrylic acid structure) have little effect on the surface orientation of the resin (X) due to the influence of the main chain, and therefore are not included in the CH3 moiety structure of the present invention.

[0348] The repeating unit having a CH3 part structure in the side chain portion is preferably the repeating unit represented by formula (B).

[0349] [Chemistry 66]

[0350] Rb1 represents a hydrogen atom, an alkyl group, a cyano group, or a halogen atom. Preferably, Rb1 is a hydrogen atom or a methyl group.

[0351] Rb2 represents an organic group having one or more CH3 moieties. Examples of Rb2 include alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, and aralkyl groups having one or more CH3 moieties. Preferably, Rb2 is an alkyl group having one or more CH3 moieties or an alkyl-substituted cycloalkyl group. Preferably, an alkyl group having one or more CH3 moieties is a branched alkyl group having 3 to 20 carbon atoms. Cycloalkyl groups having one or more CH3 moieties can be monocyclic or polycyclic. Specifically, examples include groups having monocyclic, bicyclic, tricyclic, and tetracyclic structures having 5 or more carbon atoms.

[0352] When the resin (X) contains repeating units having a CH3 moiety in the side chain portion, the content of repeating units having a CH3 moiety in the side chain portion is preferably 30 mol% to 100 mol% relative to all repeating units of the resin (X), more preferably 50 mol% to 90 mol%. The resin (X) may contain only one type of repeating unit having a CH3 moiety in the side chain portion, or it may contain two or more types.

[0353] In addition to the repeating unit, the resin (X) may also contain other repeating units (e.g., repeating units having at least one of the groups consisting of fluorine atoms and silicon atoms).

[0354] The weight-average molecular weight of resin (X) converted from standard polystyrene is not particularly limited, but is preferably 1,000 to 100,000, more preferably 1,000 to 50,000, even more preferably 2,000 to 15,000, and particularly preferably 3,000 to 15,000. Furthermore, the molecular weight distribution of resin (X) is preferably 1 to 5, more preferably 1 to 3.

[0355] The resin (X) can also be synthesized using various commercially available products, according to conventional methods (such as free radical polymerization).

[0356] When the intermediate layer contains resin (X), the content of resin (X) is not particularly limited, but is preferably 80% to 100% by mass relative to the total mass of the intermediate layer, and more preferably 90% to 100% by mass.

[0357] The intermediate layer may also contain materials other than resin (X). Examples of such materials include acid generating agents and acid diffusion control agents. Examples of compounds that may be included in the resist film include acid generating agents and acid diffusion control agents.

[0358] There are no particular limitations on the method of forming the intermediate layer. As described above, methods using the composition for forming the intermediate layer can be listed. The composition for forming the intermediate layer preferably includes the resin (X) and a solvent. There are no particular limitations on the type of solvent, but it is preferably a solvent that substantially does not dissolve the resist layer. If it is the solvent, when the composition for forming the intermediate layer is coated onto the resist layer, the dissolution of the resist layer is suppressed, and the desired laminate can be obtained efficiently. A solvent that substantially does not dissolve the resist layer refers to a solvent in which the reduction in the resist layer thickness of a 100 nm resist layer is 3.0 nm or less when the resist layer is immersed in the solvent (30 ml) for 30 seconds. The reduction in the resist layer thickness is preferably 1.5 nm or less.

[0359] There are no particular limitations on the solvent, and water and organic solvents may be listed. As organic solvents, alcohol-based solvents, ether-based solvents, hydrocarbon-based solvents, ester-based solvents, and fluorine-based solvents may be listed, with alcohol-based solvents, ether-based solvents, and hydrocarbon-based solvents being preferred. As an alcohol-based solvent, monohydric alcohols are preferred in terms of solubility in the resist layer, and more preferably monohydric alcohols with 4 to 8 carbon atoms. As monohydric alcohols, straight-chain, branched-chain, and cyclic monohydric alcohols may be listed, with straight-chain or branched-chain monohydric alcohols being preferred. Examples of alcohol solvents include: 1-butanol, 2-butanol, 3-methyl-1-butanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, isobutanol, tributanol, 1-pentanol, 2-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, and 4-octanol; glycols such as ethylene glycol, propylene glycol, diethylene glycol, and triethylene glycol; and glycol ethers such as ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and methoxymethylbutanol.

[0360] As an ether solvent, ethers with 6 to 14 carbon atoms are preferred in terms of solubility of the resist layer. Examples of ether solvents include dioxane, tetrahydrofuran, isopentyl ether, and diisopentyl ether.

[0361] As a hydrocarbon solvent, a hydrocarbon with 8 to 14 carbon atoms is preferred in terms of solubility of the resist layer. Examples of hydrocarbon solvents include: aromatic hydrocarbon solvents such as toluene, xylene, and anisole; and aliphatic hydrocarbon solvents such as n-heptane, n-nonane, n-octane, n-decane, 2-methylheptane, 3-methylheptane, 3,3-dimethylhexane, and 2,3,4-trimethylpentane.

[0362] These solvents may be used alone or in combination. For example, they may be used as mixed solvents containing alcohols and hydrocarbons, or mixed solvents containing alcohols and esters.

[0363] There is no particular limitation on the content of solvent in the composition for forming the intermediate layer. The concentration of solid components in the composition for forming the intermediate layer is preferably 1.0% to 4.0% by mass, and more preferably 1.5% to 3.0% by mass, relative to the total mass of the composition for forming the intermediate layer.

[0364] <Conductive Layer> The conductive layer is a layer disposed on the side opposite to the resist layer of the intermediate layer. By providing a conductive layer, the positional deviation of the electron beam caused by charging can be suppressed. The conductive layer preferably contains a conductive polymer. Examples of conductive polymers include polypyrrole, polythiophene, polythiophene vinylene, polytellurophene, polyphenylene, polyphenylene vinylene, polyaniline, polyacene, polyacetylene, and derivatives thereof.

[0365] The conductive polymer is preferably water-soluble or water-dispersible. If the conductive polymer is water-soluble or water-dispersible, the coatability of the conductive layer forming composition is improved, and a conductive body with a uniform film thickness can be easily obtained. In addition, if the conductive polymer is water-soluble or water-dispersible, when the intermediate layer contains a resin soluble in alkaline developing solution or a resin soluble in organic developing solution, a conductive layer can be formed without dissolving the intermediate layer by using a conductive layer forming composition with water as a solvent.

[0366] The conductive polymer preferably has an acid group or its salt. Examples of acid groups include sulfonic acid groups and carboxyl groups. Examples of salts of acid groups include alkali metal salts, alkaline earth metal salts, ammonium salts, and substituted ammonium salts of sulfonic acid groups or carboxylic acid groups.

[0367] As a conductive polymer, it is preferred to be a π-conjugated conductive polymer comprising at least one of the following groups as repeating units: phenyl-vinyl ...

[0368] As a conductive polymer, it is preferred to be a conductive polymer having sulfonic acid groups or polyaniline.

[0369] Conductive polymers can also be synthesized using various commercially available products and according to conventional methods.

[0370] When the conductive layer contains a conductive polymer, there is no particular limitation on the content of the conductive polymer, but it is preferably 80% to 100% by mass relative to the total mass of the conductive layer, and more preferably 90% to 100% by mass.

[0371] The conductive layer may also contain materials other than conductive polymers. Examples of such materials include surfactants and antioxidants.

[0372] There are no particular limitations on the method for forming the conductive layer. As described above, methods using a composition for forming the conductive layer can be listed. The composition for forming the conductive layer preferably includes the conductive polymer and a solvent. There are no particular limitations on the type of solvent, but it is preferably a solvent that substantially does not dissolve the intermediate layer. If such a solvent is used, when the composition for forming the conductive layer is coated onto the intermediate layer, the dissolution of the intermediate layer is suppressed, and the desired laminate can be obtained efficiently. A solvent that substantially does not dissolve the intermediate layer refers to a solvent in which, when a 100 nm thick intermediate layer is immersed in the solvent (30 ml) for 30 seconds, the reduction in film thickness of the intermediate layer is 3.0 nm or less. Preferably, the reduction in film thickness of the intermediate layer is 1.5 nm or less.

[0373] There are no particular limitations on the solvent, and water and organic solvents may be listed. As organic solvents, alcohol solvents, ether solvents, hydrocarbon solvents, ester solvents and fluorinated solvents may be listed, with alcohol solvents, ether solvents and hydrocarbon solvents being preferred.

[0374] There is no particular limitation on the content of solvent in the composition for forming the conductive layer. The concentration of solid components in the composition for forming the conductive layer is preferably 0.5% to 4.0% by mass, and more preferably 1.0% to 3.0% by mass, relative to the total mass of the composition for forming the conductive layer.

[0375] As a preferred combination of the composition for forming the intermediate layer and the composition for forming the conductive layer, examples include those in which either the solvent in the composition for forming the intermediate layer or the solvent in the composition for forming the conductive layer is water, and the other is an organic solvent. In such cases, a conductive layer can be formed on the intermediate layer while suppressing the dissolution of the intermediate layer. [Example]

[0376] The following examples and comparative examples illustrate the features of the present invention in more detail. The materials, amounts, proportions, processing contents, and processing procedures shown in the following examples may be appropriately modified without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be interpreted restrictively by the specific examples shown below.

[0377] <Various Components of the Resist Layer Formation> (Acid-Degradable Resin) Resins P-1 to P-13 shown in Table 1 are listed below. Resins P-1 to P-13 were synthesized according to the synthesis method of resin P-1 described later (Synthesis Example 1). Table 1 shows the composition ratio (moles %; corresponding from left to right), weight average molecular weight (Mw), and dispersity (Mw / Mn) of each repeating unit of resins P-1 to P-13. Furthermore, the weight average molecular weight (Mw) and dispersity (Mw / Mn) of resins P-1 to P-13 were determined by GPC (carrier: tetrahydrofuran (THF)) (converted to polystyrene). In addition, the composition ratio (moles %) of the resins was determined by 13C nuclear magnetic resonance (NMR).

[0378] [Table 1] resin Composition ratio (mol%) Weight-average molecular weight (Mw) Dispersion P-1 40 / 60 8,000 1.6 P-2 30 / 65 / 5 6,500 1.5 P-3 50 / 50 5,500 1.4 P-4 40 / 60 6,000 1.5 P-5 35 / 65 8,000 1.7 P-6 30 / 20 / 50 12,000 1.8 P-7 40 / 10 / 50 4,500 1.4 P-8 35 / 25 / 40 6,000 1.4 P-9 40 / 20 / 40 8,000 1.5 P-10 30 / 10 / 60 12,000 1.7 P-11 90 / 10 6,000 1.5 P-12 50 / 30 / 20 6,000 1.5 P-13 25 / 20 / 55 9,000 1.6

[0379] (Synthesis Example 1: Synthesis of Resin P-1) Cyclohexanone (194.3 g) was placed in a three-necked flask under a nitrogen stream and heated to 80°C. Over 6 hours, a solution was added dropwise to obtain monomers corresponding to the repeating units of resin P-1 (described later, 15.3 g and 45.8 g from left to right), and polymerization initiator V-601 (manufactured by Fujifilm and Koimitsu Chemical Co., Ltd., 3.17 g) dissolved in 105 g of cyclohexanone. After the addition was complete, the reaction solution was allowed to react at 80°C for 2 hours. After cooling, the reaction solution was added dropwise over 20 minutes to a mixture of methanol and water. The powder precipitated by the addition was then filtered and dried to obtain resin P-1 (31.6 g), an acid-degradable resin. The molar ratio of the repeating units determined by NMR was 40 / 60. The obtained resin P-1 has a weight-average molecular weight of 8,000 converted to standard polystyrene and a dispersion (Mw / Mn) of 1.6.

[0380] The following shows the structural formulas of the resins P-1 to P-13 used.

[0381] [Chemical 67]

[0382] (Acid generating agent) The structure of the acid generating agent (PAG-1 to PAG-10) used is shown below.

[0383] [Transformation 68]

[0384] Table 2 shows the acid dissociation constant (pKa) and size (volume of acid produced) of acids produced by the acid-generating agents (PAG-1 to PAG-10). Furthermore, when determining the acid dissociation constant (pKa) of acids produced by the acid-generating agents (PAG-1 to PAG-10), specifically, compounds formed by substituting each cation site of PAG-1 to PAG-10 with H+ (for example, in the case of X-1, compounds formed by substituting the triphenylstrontium cation with H+) were used. As described above, software package 1 from ACD / Labs was used, and values ​​based on Hammett substituent constants and known literature values ​​were calculated. Additionally, when the pKa could not be calculated using the aforementioned method, values ​​obtained using density functional theory (DFT) and Gaussian 16 were used. A smaller pKa value indicates a higher acidity.

[0385] [Table 2] PAG Acid pKa is generated Acid volume produced (Å) 3 ) PAG-1 -0.29 174 PAG-2 -2.06 225 PAG-3 -0.22 391 PAG-4 -0.63 282 PAG-5 -1.37 254 PAG-6 -2.43 260 PAG-7 -2.80 372 PAG-8 -2.72 312 PAG-9 -0.88 592 PAG-10 -3.27 254

[0386] (Acid diffusion control agent) The structure of the acid diffusion control agent (Q-1 to Q-4) used is shown below.

[0387] [Transformation 69]

[0388] (Crosslinking agent) The structure of the crosslinking agent (CL-1) used is shown below.

[0389] [Chemistry 70]

[0390] (Resin for Intermediate Layer) The structure of the resins (MLP-1 to MLP-3) used in the formation of the intermediate layer is shown below. Furthermore, the values ​​recorded in each repeating unit in the structural formula (e.g., 85, 10, and 5 in the case of MLP-1) represent the content (moles%) of each repeating unit relative to all repeating units. In the structural formula, Mw represents the weight average molecular weight, and Pd represents the molecular weight distribution.

[0391] [Chemistry 71]

[0392] (Resin for Conductive Layer) The following describes the manufacturing process of the resin (ULP-1) used in the formation of the conductive layer. ULP-1: A polymer of 2-aminoanisole-4-sulfonic acid obtained by the following manufacturing method. Pyridine (100 mmol) and water (100 mL) were added to 2-aminoanisole-4-sulfonic acid (100 mmol) to obtain a monomer solution. An aqueous solution of ammonium peroxide (100 mmol) (oxidizing agent solution) was added dropwise to the obtained monomer solution at 10°C. After the addition was completed, the reaction solution was stirred at 25°C for 15 hours, then heated to 35°C and stirred for 2 hours to obtain a reaction solution with a precipitate of the reaction product (polymerization step). The obtained reaction solution was filtered using a centrifugal filter to recover the precipitate (reaction product). After washing the reaction product with 1 L of methanol, it was dried to obtain a powdered conductive polymer (ULP-1) (purification step).

[0393] (Surfactants) The following shows the surfactants used. W-1: Megafac F176 (manufactured by DIC (stock); fluorine-based) W-2: Megafac R08 (manufactured by DIC (stock); fluorine and silicon-based)

[0394] (Solvents) The solvents used are shown below. SL-1: Propylene glycol monomethyl ether acetate (PGMEA) SL-2: Propylene glycol monomethyl ether (PGME) SL-3: Diacetone alcohol SL-4: γ-Butyrolactone SL-5: 4-Methyl-2-pentanol SL-6: Diisopentane SL-7: n-Undecane SL-8: Pure water SL-9: Isopropanol

[0395] <Preparation of Resist Layer Forming Compositions> Resist layer forming compositions were prepared by mixing raw materials according to the compositions shown in Table 3 below and filtering the obtained mixture using a polyethylene filter with a pore size of 0.03 μm. The solid content concentration of each resist layer forming composition was appropriately adjusted according to the film thickness coating method shown in Tables 6, 8, and 10 below. The solid content concentration in each resist layer forming composition was 2.0% by mass to 6.0% by mass relative to the total mass of the resist layer forming composition.

[0396] [Table 3] Composition for forming resist layer Acid-degradable resins Acid generating agent Acid diffusion control agent Crosslinking agent surfactants solvent type content (by weight) type content (by weight) type content (by weight) type content (by weight) type content (by weight) R-1 P-1 86.0 PAG-1 9.0 Q-1 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-2 P-2 90.0 - - Q-1 10.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-3 P-1 75.0 PAG-1 15.0 Q-1 10.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-4 P-1 68.0 PAG-1 22.0 Q-1 10.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-5 P-1 86.0 PAG-2 9.0 Q-1 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-6 P-1 89.0 PAG-3 9.0 Q-1 2.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-7 P-1 86.0 PAG-1 9.0 Q-2 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-8 P-1 86.0 PAG-1 9.0 Q-3 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-9 P-1 91.0 PAG-4 9.0 - - - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-10 P-3 89.0 PAG-1 9.0 Q-1 2.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-11 P-4 89.0 PAG-1 9.0 Q-1 2.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-12 P-5 86.0 PAG-1 9.0 Q-1 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-13 P-6 86.0 PAG-1 9.0 Q-1 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-14 P-7 72.0 PAG-5 18.0 Q-2 10.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-15 P-7 66.7 PAG-6 23.0 Q-3 10.0 - - W-1 0.3 SL-1 / SL-2=80 / 20 R-16 P-8 76.8 PAG-7 13.0 Q-4 10.0 - - W-2 0.2 SL-1 / SL-2=80 / 20 R-17 P-9 85.0 PAG-8 9.0 Q-4 6.0 - - - - SL-1 / SL-2=80 / 20 R-18 P-10 84.0 PAG-9 11.0 Q-1 5.0 - - - - SL-1 / SL-3=40 / 60 R-19 P-6 77.0 PAG-7 13.0 Q-4 10.0 - - - - SL-1 / SL-3=40 / 60 R-20 P-7 85.0 PAG-4 15.0 - - - - - - SL-1 / SL-3=40 / 60 R-21 P-8 79.7 PAG-10 15.0 Q-1 5.0 - - W-1 0.3 SL-2 / SL-3=50 / 50 R-22 P-9 70.0 PAG-4 / PAG-8 15.0 / 5.0 Q-2 10.0 - - - - SL-3 / SL-4=90 / 10 R-23 P-10 68.0 PAG-7 22.0 Q-2 10.0 - - - - SL-1 / SL-2=80 / 20 R-24 P-7 62.0 PAG-3 / PAG-5 14.0 / 14.0 Q-1 10.0 - - - - SL-1 / SL-2=80 / 20 R-25 P-1 86.0 PAG-1 9.0 Q-1 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-26 P-1 86.0 PAG-1 9.0 Q-1 5.0 - - - - SL-1 / SL-2 / SL-4=80 / 15 / 5 R-27 P-11 62.0 PAG-9 12.0 Q-3 6.0 CL-1 20.0 - - SL-1 / SL-2=80 / 20 R-28 P-12 77.0 PAG-9 15.0 Q-3 8.0 - - - - SL-1 / SL-2=80 / 20 R-29 P-13 77.0 PAG-8 15.0 Q-3 8.0 - - - - SL-1 / SL-2=80 / 20

[0397] <Preparation of Intermediate Layer Forming Compositions> Intermediate layer forming compositions were prepared by filtering the obtained mixture of raw materials according to the compositions shown in Table 4 below using a polyethylene filter with a pore size of 0.03 μm. The solid content concentration of each intermediate layer forming composition was appropriately adjusted according to the film thickness coating method shown in Tables 6, 8, and 10 below. The solid content concentration in each intermediate layer forming composition was 2.0% to 4.0% by mass relative to the total mass of the intermediate layer forming composition. Furthermore, the solvents contained in the intermediate layer forming compositions in each embodiment were equivalent to solvents that substantially do not dissolve the resist layer. Additionally, the resins contained in the intermediate layer forming compositions in each embodiment were equivalent to resins soluble in the developer solution.

[0398] [Table 4] intermediate layer formation components resin Acid generating agent Acid diffusion control agent solvent type content (by weight) type content (by weight) type content (by weight) M-1 MLP-1 100.0 - - - - SL-6 / SL-7=80 / 20 M-2 MLP-2 95.0 - - Q-4 5.0 SL-5 / SL-7=60 / 40 M-3 MLP-3 95.0 PAG-2 5.0 - - SL-5 / SL-6 / SL-7=30 / 40 / 30

[0399] <Preparation of the Composition for Forming the Conductive Layer> The raw materials were mixed according to the composition shown in Table 5 below, and the obtained mixture was filtered through a polyethylene filter with a pore size of 0.03 μm to prepare the composition for forming the conductive layer. The concentration of the solid components in each composition for forming the conductive layer was appropriately adjusted according to the film thickness coating method shown in Tables 6, 8 and 10 below. The concentration of the solid components in the composition for forming the conductive layer was 1.0% to 3.0% by mass relative to the total mass of the composition for forming the conductive layer. Furthermore, the solvents contained in the composition for forming the conductive layer are equivalent to solvents that substantially do not dissolve the intermediate layer in each embodiment.

[0400] [Table 5] Composition for forming conductive layer resin solvent type content (by weight) U-1 ULP-1 100.0 SL-8 / SL-9=95 / 5

[0401] <Developer and Rinse Solution> The following shows the developer and rinse solution used. D-1: 2.38% by mass tetramethylammonium hydroxide aqueous solution D-2: Pure water D-3: FIRM Extreme 10 (manufactured by AZEM) D-4: Butyl acetate D-5: n-Undecane

[0402] <Examples 1-24, Comparative Examples 1-5> Using ACTM (manufactured by Tokyo Electron, Ltd.), under the conditions described in Table 6, a resist layer forming composition, an intermediate layer forming composition, and a conductive layer forming composition were sequentially spin-coated onto a blank mask with a 152 mm square outermost surface being Cr to form a laminate. Furthermore, after coating each composition, heat treatment was performed under the conditions shown in the "Pre-Bake" column of Table 6. Next, exposure was performed using an electron beam exposure apparatus (EBM-9000 manufactured by Nuflare Technology, Ltd., with an accelerating voltage of 50 kV). Then, post-exposure baking (PEB) was performed under the conditions described in Table 6. Afterward, development was performed using the developer described in Table 6, followed by rinsing using the rinsing solution described in Table 6 to obtain a positive pattern.

[0403] <Evaluation> The patterned blank mask was observed using a high-altitude scanning electron microscope (SEM). The optimal exposure (μC / cm2) was set to the exposure at which the 50 nm 1:1 line and space (LS) were resolved at a 1:1 ratio. The PSD(0)LER (nm3) of the 50 nm LS at this exposure was calculated. The results are summarized in Table 6. Furthermore, as a method for calculating the PSD(0)LER, the measurement data obtained by high-altitude SEM (scanning electron microscope) was analyzed using MetroLER software manufactured by Fralitier, and the PSD(0)LER was calculated under the condition of removing measurement noise. PSD(0)LER represents the low-frequency component of PSD. The smaller the value of PSD(0)LER, the smaller the long-period fluctuation in the pattern length direction, and the better the performance.

[0404] <Evaluation Method for Film Reduction of Each Layer> The film reduction of the resist layer was evaluated using the following method. First, the resist layer forming composition used in the examples and comparative examples was coated on a silicon wafer with a diameter of 200 mm, and heat treatment was performed under the conditions in the "Pre-baking" column of the "Resist Coating Conditions" column in Table 6 to prepare a resist layer (film thickness 100 nm). Second, the film reduction of the resist layer (nm) was measured when the prepared resist layer was immersed in the solvent (30 ml) contained in the intermediate layer forming composition coated on the resist layer of the examples and comparative examples for 30 seconds. Furthermore, the film reduction refers to the reduction in film thickness after immersion treatment starting from the initial film thickness of 100 nm. For example, regarding Example 1, a resist layer (film thickness 100 nm) was fabricated using resist layer composition R-1 under specified heating conditions. The fabricated resist layer was then immersed in a solvent (SL-6 / SL-7=80 / 20) contained in the intermediate layer composition for 30 seconds, and the reduction in film thickness of the resist layer was measured. The results are summarized in Table 7. Furthermore, the reduction in film thickness of the intermediate layer was evaluated using the following method. First, the intermediate layer composition used in each example and comparative example was coated onto a 200 mm diameter silicon wafer, and a heat treatment was performed under the conditions specified in the "Pre-baking" column of the "Intermediate Layer Coating Conditions" section of Table 6 to fabricate an intermediate layer (film thickness 100 nm). Second, the reduction in film thickness (nm) of the intermediate layer was measured when the fabricated intermediate layer was immersed in a solvent (30 ml) contained in the conductive layer composition coated on the intermediate layer of each example and comparative example for 30 seconds. Furthermore, the film reduction refers to the reduction in film thickness after immersion treatment starting from an initial film thickness of 100 nm. The results are summarized in Table 7. Additionally, the film reduction of the intermediate layer relative to the developing solution was evaluated using the following method. First, the intermediate layer formation composition used in each example and comparative example was coated onto a 200 mm diameter silicon wafer, and a heat treatment was performed under the conditions specified in the "Pre-baking" column of the "Intermediate Layer Coating Conditions" section of Table 6 to form an intermediate layer (film thickness 100 nm). Second, the film reduction (nm) of the intermediate layer was measured when the formed intermediate layer was immersed in the developing solution (30 ml) used in each example and comparative example for 30 seconds. Furthermore, the film reduction refers to the reduction in film thickness after immersion treatment starting from an initial film thickness of 100 nm. The results are summarized in Table 7. Additionally, the film reduction of the conductive layer relative to the developing solution was evaluated using the following method. First, the conductive layer forming composition used in each embodiment and comparative example was coated on a silicon wafer with a diameter of 200 mm, and heat treatment was performed under the conditions of the "Pre-baking" column in the "Conductive Layer Coating Conditions" column of Table 6 to form a conductive layer (film thickness 100 nm).Next, the reduction in film thickness (nm) of the conductive layer was measured after immersing the prepared conductive layer in the developing solution (30 ml) used in each embodiment and comparative example for 30 seconds. Furthermore, the reduction in film thickness refers to the reduction in film thickness after immersion treatment starting from an initial film thickness of 100 nm. The results are summarized in Table 7.

[0405] In Table 6, the "film thickness (nm)" column in the "Resist Coating Conditions" column refers to the film thickness of the resist layer, the "film thickness (nm)" column in the "Intermediate Layer Coating Conditions" column refers to the film thickness of the intermediate layer, and the "film thickness (nm)" column in the "Conductive Layer Coating Conditions" column refers to the film thickness of the conductive layer.

[0406] [Table 6] Resist Coating Conditions Intermediate layer coating conditions conductive layer coating conditions PEB / Developing Conditions evaluate (nm) 3 ) Composition Film thickness (nm) Pre-baking Composition Film thickness (nm) Pre-baking Composition Film thickness (nm) Pre-baking PEB Developer Rinse solution Example 1 R-1 150 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 6.7 Example 2 R-2 140 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.9 Example 3 R-3 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.6 Example 4 R-4 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.4 Example 5 R-5 80 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.6 Example 6 R-6 90 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.6 Example 7 R-7 40 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.4 Example 8 R-8 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.5 Example 9 R-9 140 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.5 Example 10 R-10 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.7 Example 11 R-11 120 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.3 Example 12 R-12 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.2 Example 13 R-13 90 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.0 Example 14 R-14 80 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.9 Example 15 R-15 70 120℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 120℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.8 Example 16 R-16 90 100℃ / 300 seconds M-1 60 100℃ / 300 seconds U-1 20 120℃ / 300 seconds 120℃ / 300 seconds D-1 D-2 4.7 Example 17 R-17 80 100℃ / 300 seconds M-1 60 80℃ / 300 seconds U-1 20 100℃ / 300 seconds 100℃ / 300 seconds D-1 D-3 5.1 Example 18 R-18 70 100℃ / 300 seconds M-2 60 120℃ / 300 seconds U-1 40 100℃ / 300 seconds 100℃ / 300 seconds D-1 D-3 4.6 Example 19 R-19 100 100℃ / 300 seconds M-2 60 90℃ / 300 seconds U-1 60 100℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.7 Example 20 R-20 40 120℃ / 300 seconds M-2 50 120℃ / 300 seconds U-1 50 110℃ / 300 seconds 110℃ / 300 seconds D-1 D-2 5.1 Example 21 R-21 50 100℃ / 300 seconds M-1 100 120℃ / 300 seconds U-1 60 120℃ / 300 seconds 100℃ / 300 seconds D-1 D-3 4.8 Example 22 R-22 100 120℃ / 300 seconds M-2 60 120℃ / 300 seconds U-1 20 80℃ / 300 seconds 90℃ / 300 seconds D-1 D-2 4.9 Example 23 R-23 80 100℃ / 300 seconds M-1 80 120℃ / 300 seconds U-1 15 120℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.2 Example 24 R-24 90 100℃ / 300 seconds M-1 40 120℃ / 300 seconds U-1 30 100℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.2 Comparative Example 1 R-25 160 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 10.7 Comparative Example 2 R-26 180 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 12.0 Comparative Example 3 R-19 100 100℃ / 300 seconds - - - U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 11.2 Comparative Example 4 R-19 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds - - - 100℃ / 300 seconds D-1 D-2 11.4 Comparative Example 5 R-19 100 100℃ / 300 seconds - - - - - - 100℃ / 300 seconds D-1 D-2 11.2

[0407] [Table 7] The amount of reduction in the amount of solvent film in the resist layer relative to the intermediate layer composition. (nm) The amount of film reduction of the solvent in the composition of the intermediate layer relative to the conductive layer. (nm) The reduction in film size of the intermediate layer relative to the developer. (nm) The reduction in the amount of conductive layer relative to the developing solution film (nm) Example 1 1.2 0.5 100 100 Example 2 0.9 0.4 100 100 Example 3 0.5 0.3 100 100 Example 4 0.8 0.9 100 100 Example 5 1.1 1.2 100 100 Example 6 1.3 1.1 100 100 Example 7 0.8 0.8 100 100 Example 8 0.7 1.4 100 100 Example 9 1.2 0.9 100 100 Example 10 0.5 0.5 100 100 Example 11 0.2 0.3 100 100 Example 12 0.4 0.4 100 100 Example 13 1.1 0.5 100 100 Example 14 0.1 0.7 100 100 Example 15 1.4 1.1 100 100 Example 16 0.3 1.2 100 100 Example 17 0.2 0.8 100 100 Example 18 0.4 0.2 100 100 Example 19 0.5 0.1 100 100 Example 20 2.4 0.9 100 100 Example 21 0.6 0.7 100 100 Example 22 0.7 0.6 100 100 Example 23 1.2 0.5 100 100 Example 24 0.9 0.4 100 100 Comparative Example 1 0.9 0.2 100 100 Comparative Example 2 0.9 0.4 100 100 Comparative Example 3 - - - 100 Comparative Example 4 0.9 - 100 - Comparative Example 5 - - - -

[0408] As shown in Table 6, the desired effect can be obtained according to the pattern forming method of the present invention. Furthermore, a comparison of Examples 1 and 3-4 confirms that when the content of the compound that generates acid by electron beam irradiation is 10% by mass or more relative to the total mass of the resist layer, a more superior effect can be obtained. Additionally, a comparison of Examples 1 and 5 confirms that when the pKa of the acid generated by the compound that generates acid by electron beam irradiation is -1.00 or less, a more superior effect can be obtained. Furthermore, a comparison of Examples 1 and 6 confirms that when the size of the acid generated by the compound that generates acid by electron beam irradiation is 240 Å3 or more, a more superior effect can be obtained. Furthermore, a comparison of Examples 1 and 7-8 confirms that when the resist layer contains an alkaline compound whose alkalinity is reduced or eliminated by electron beam irradiation, a more superior effect can be obtained. Furthermore, a comparison of Examples 1 and 9 confirms that when the resist layer contains the compound (I), a more superior effect can be obtained. Furthermore, when the resist layer contains the compound (II), even better results can be obtained. Additionally, a comparison of Example 1 and Example 10 confirms that when the resin contained in the resist layer contains repeating units having fluorinated alcohol groups, even better results can be obtained. Furthermore, a comparison of Example 1 and Example 11 confirms that when the resin contained in the resist layer contains repeating units having groups that decompose to produce carboxyl groups under acid action, even better results can be obtained. Furthermore, a comparison of Example 1 and Example 12 confirms that when the resin contained in the resist layer contains repeating units having groups that decompose to produce phenolic hydroxyl groups under acid action, and having groups represented by formula (Y1) that act as releasing groups that are released under acid action, even better results can be obtained. Furthermore, a comparison of Example 1 and Example 13 confirms that when the resin contained in the resist layer contains repeating units having lactone groups, even better results can be obtained. Furthermore, even better results can be obtained when the resin contained in the resist layer contains repeating units with sulfonyl lactone or carbonate groups.

[0409] <Examples 25-26, Comparative Examples 6-9> Using ACTM (manufactured by Tokyo Electron, Ltd.), under the conditions described in Table 8, a resist layer forming composition, an intermediate layer forming composition, and a conductive layer forming composition were sequentially spin-coated onto a blank mask with a 152 mm square outermost surface of Cr to form a laminate. Furthermore, after coating each composition, heat treatment was performed under the conditions shown in the "Pre-baking" column of Table 8. Next, exposure was performed using an electron beam exposure apparatus (EBM-9000 manufactured by Nuflare Technology, Ltd., with an accelerating voltage of 50 kV). Then, PEB (post-exposure baking) was performed under the conditions described in Table 8. Afterward, development was performed using the developer described in Table 8, followed by rinsing using the rinsing solution described in Table 8 to obtain a negative pattern. The obtained pattern was subjected to the <Evaluation> described above. The results are summarized in Table 8. In addition, the "Evaluation Method for Membrane Reduction in Each Layer" was implemented. The results are summarized in Table 9.

[0410] [Table 8] Resist Coating Conditions Intermediate layer coating conditions conductive layer coating conditions PEB / Developing Conditions Evaluation (nm) 3 ) Composition Film thickness (nm) Pre-baking Composition Film thickness (nm) Pre-baking Composition Film thickness (nm) Pre-baking PEB Developer Rinse solution Example 25 R-27 150 100℃ / 300 seconds M-2 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 4.6 Example 26 R-28 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 5.0 Comparative Example 6 R-27 160 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 11.0 Comparative Example 7 R-27 100 100℃ / 300 seconds - - - U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-1 D-2 10.9 Comparative Example 8 R-27 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds - - - 100℃ / 300 seconds D-1 D-2 10.6 Comparative Example 9 R-27 100 100℃ / 300 seconds - - - - - - 100℃ / 300 seconds D-1 D-2 11.4

[0411] [Table 9] The amount of reduction in the amount of solvent film in the resist layer relative to the intermediate layer composition. (nm) The amount of film reduction of the solvent in the composition of the intermediate layer relative to the conductive layer. (nm) The reduction in film size of the intermediate layer relative to the developer. (nm) The reduction in the amount of conductive layer relative to the developing solution film (nm) Example 25 2.3 0.5 100 100 Example 26 0.9 0.4 100 100 Comparative Example 6 0.5 0.3 100 100 Comparative Example 7 - - - 100 Comparative Example 8 0.9 - 100 - Comparative Example 9 - - - -

[0412] As shown in Table 8, the desired effect can be obtained by the pattern forming method according to the present invention.

[0413] <Examples 27-28, Comparative Examples 10-13> Using ACTM (manufactured by Tokyo Electron, Ltd.), under the conditions described in Table 10, a resist layer forming composition, an intermediate layer forming composition, and a conductive layer forming composition were sequentially spin-coated onto a blank mask with a 152 mm square outermost surface of Cr to form a laminate. Furthermore, after coating each composition, heat treatment was performed under the conditions shown in the "Pre-baking" column of Table 10. Next, exposure was performed using an electron beam exposure apparatus (EBM-9000 manufactured by Nuflare Technology, Ltd., with an accelerating voltage of 50 kV). Then, PEB (post-exposure baking) was performed under the conditions described in Table 10. Afterward, development was performed using the developer described in Table 10, followed by rinsing using the rinsing solution described in Table 10 to obtain a negative pattern. The obtained pattern was subjected to the <Evaluation> described above. The results are summarized in Table 10. In addition, the "Membrane Reduction Evaluation Method for Each Layer" was implemented. The results are summarized in Table 11.

[0414] [Table 10] Resist Coating Conditions Intermediate layer coating conditions conductive layer coating conditions PEB / Developing Conditions Evaluation (nm) 3 ) Composition Film thickness (nm) Pre-baking Composition Film thickness (nm) Pre-baking Composition Film thickness (nm) Pre-baking PEB Developer Rinse solution Example 27 R-29 100 100℃ / 300 seconds M-1 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-4 D-5 4.9 Example 28 R-29 150 100℃ / 300 seconds M-3 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-4 - 4.9 Comparative Example 10 R-29 160 100℃ / 300 seconds M-3 60 120℃ / 300 seconds U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-4 - 10.7 Comparative Example 11 R-29 100 100℃ / 300 seconds - - - U-1 20 90℃ / 300 seconds 100℃ / 300 seconds D-4 - 11.0 Comparative Example 12 R-29 100 100℃ / 300 seconds M-3 60 120℃ / 300 seconds - - - 100℃ / 300 seconds D-4 - 11.9 Comparative Example 13 R-29 100 100℃ / 300 seconds - - - - - - 100℃ / 300 seconds D-4 - 11.5

[0415] [Table 11] The amount of reduction in the amount of solvent film in the resist layer relative to the intermediate layer composition. (nm) The amount of film reduction of the solvent in the composition of the intermediate layer relative to the conductive layer. (nm) The reduction in film size of the intermediate layer relative to the developer. (nm) The reduction in the amount of conductive layer relative to the developing solution film (nm) Example 27 1.2 0.5 100 100 Example 28 0.9 0.4 100 100 Comparative Example 10 0.5 0.3 100 100 Comparative Example 11 - - - 100 Comparative Example 12 0.9 - 100 - Comparative Example 13 - - - -

[0416] As shown in Table 10, the desired effect can be obtained by the pattern forming method according to the present invention. [Simplified Explanation of the Diagram]

[0010] None

Claims

1. A method for forming a pattern, comprising: Step 1: Fabricate a laminate consisting of a substrate, a resist layer, an intermediate layer, and a conductive layer in sequence; Step 2, irradiating the stacked body with an electron beam in a patterned manner; and Step 3, performing a development process on the stacked body irradiated with the electron beam to form a pattern, wherein the thickness of the resist layer is less than 150 nm, wherein Step 1 includes: Step 1A, coating a composition for forming a resist layer on a substrate to form the resist layer. Step 1B, forming the intermediate layer by coating the resist layer with a composition for forming an intermediate layer; and Step 1C, forming the conductive layer by coating the intermediate layer with a composition for forming a conductive layer.

2. The pattern forming method as claimed in claim 1, wherein the resist layer comprises a resin whose solubility relative to the developer changes due to the action of an acid, and satisfies at least one of requirements 1 and 2 below: requirement 1: the resist layer comprises a compound that generates an acid by irradiation with an electron beam; requirement 2: the resin comprises repeating units having residues formed by removing a hydrogen atom from the compound that generates an acid by irradiation with an electron beam.

3. The pattern forming method as claimed in claim 2, wherein, when requirement 1 is satisfied, the content of the compound is 10% by mass or more relative to the total mass of the resist layer, and when requirement 2 is satisfied, the content of the repeating unit is 10% by mass or more relative to the total mass of the resist layer.

4. The pattern forming method as claimed in claim 2, wherein the pKa of the acid produced from the compound that generates acid by irradiation with an electron beam is -1.00 or less.

5. The pattern forming method as claimed in claim 2, wherein the size of the acid produced from the compound that generates acid by irradiation with an electron beam is 240 Å 3 or more.

6. The pattern forming method as claimed in claim 2, wherein the compound that generates acid by electron beam irradiation is one or more compounds selected from compounds (I) and (II), wherein: Compound (I): a compound having one or more structural sites X and one or more structural sites Y and generating acid by electron beam irradiation, the acid comprising a first acidic site derived from structural site X and a second acidic site derived from structural site Y; Structural site X: a structural site comprising an anionic site A1- and a cation site M1+ and forming a first acidic site represented by HA1 by electron beam irradiation; Structural site Y: a structural site comprising an anionic site A2- and a cation site M2+ and forming a second acidic site represented by HA2 by electron beam irradiation, wherein... Compound (I) satisfies the following condition I: Condition I: In compound (I), compound PI formed by replacing the cation M1+ in structural site X and the cation M2+ in structural site Y with H+ has an acid dissociation constant a1 derived from the acidic site represented by HA1, formed by replacing the cation M1+ in structural site X with H+, and an acid dissociation constant a2 derived from the acidic site represented by HA2, formed by replacing the cation M2+ in structural site Y with H+, and the acid dissociation constant a2 is greater than the acid dissociation constant a1; Compound (II): A compound having two or more structural sites X and one or more structural sites Z and producing an acid by electron beam irradiation, the acid comprising two or more first acidic sites and structural sites Z derived from structural sites X, Structural site Z: a ​​site capable of neutralizing the nonionic nature of the acid.

7. The pattern forming method as claimed in claim 2, wherein the resin comprises repeating units having acid groups.

8. The pattern forming method as claimed in claim 7, wherein the acid group is selected from the group consisting of phenolic hydroxyl groups and fluorinated alcohol groups.

9. The pattern forming method as claimed in claim 2, wherein the resin comprises repeating units having a group that decomposes by the action of an acid to produce a carboxyl group.

10. The pattern forming method as claimed in claim 2, wherein the resin comprises repeating units having phenolic hydroxyl groups that are decomposed by the action of an acid.

11. The pattern forming method as claimed in claim 2, wherein the resin comprises repeating units having at least one group selected from the group consisting of lactone, sulcinolone, and carbonate groups.

12. The pattern forming method as claimed in claim 1, wherein the resist layer comprises an alkaline compound whose alkalinity is reduced or eliminated by irradiation with an electron beam.

13. The pattern forming method of claim 12, wherein the alkaline compound comprises an onium salt compound that produces an acid by electron beam irradiation, the acid produced from the onium salt compound being a weak acid compared to the acid produced from the compound that produces an acid by electron beam irradiation.

14. The pattern forming method as claimed in claim 1, wherein the intermediate layer is soluble in the developing solution used in the developing process.

15. The pattern forming method of claim 1, wherein the intermediate layer is a layer formed using an intermediate layer forming composition comprising a resin soluble in the developer used in the developing process and a solvent substantially insoluble in the resist layer.

16. The pattern forming method as claimed in claim 15, wherein the solvent that does not substantially dissolve the resist layer is selected from the group consisting of monohydric alcohols having 4 to 10 carbon atoms, ethers having 6 to 14 carbon atoms, and hydrocarbons having 8 to 14 carbon atoms.

17. The pattern forming method of claim 15, wherein the resin soluble in the developing solution used in the developing process comprises a repeating unit having at least one group selected from the group consisting of carboxyl, phenolic hydroxyl, fluorinated alcohol, sulfonic acid, and sulfonamide.

18. A method for manufacturing an electronic component, comprising a pattern forming method as described in any one of claims 1 to 17.

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