Conductive composition, conductive film, and laminate

Abstract

This conductive composition contains: a conductive polymer (A) having an acidic group; and a basic compound (B) having a cyclic amide and an amino group in each molecule. The conductive film according to the present invention is formed from the conductive composition. This laminate comprises a substrate, a resist layer for electron beams, which is formed on at least one surface of the substrate, and the conductive film, which is formed on the resist layer for electron beams.

Description

This application is a divisional application of the following application. Parent case filing date: April 10, 2019 Parent application number: 201980020476.2 (PCT / JP2019 / 015602) Parent application name: Conductive composition, conductive film, and laminate Technical Field

[0001] The present invention relates to a conductive composition, a conductive film, and a laminate. This application claims priority based on Japanese Patent Application No. 2018-075578, filed in Japan on April 10, 2018, the contents of which are incorporated herein by reference. Background Art

[0002] Patterning technology using charged particle beams such as electron beams and ion beams is expected to be the next generation of photolithography technology. When using charged particle beams, it is important to improve productivity and enhance the sensitivity of the resist. Therefore, the use of highly sensitive chemically amplified resists that generate acid in exposed areas or areas irradiated with a charged particle beam and then promote crosslinking or decomposition reactions through a heat treatment called post-exposure bake (PEB) is becoming mainstream.

[0003] However, in patterning methods using a charged particle beam, particularly when the substrate is insulating, there is a problem that the trajectory of the charged particle beam is bent by the electric field generated by charging the substrate, making it difficult to obtain a desired pattern. As a means for solving this problem, it is known that a conductive composition containing a conductive polymer is applied to the surface of the resist layer to form a conductive coating film (hereinafter referred to as "conductive film"), and the surface of the resist layer is covered with the conductive film.

[0004] As a conductive polymer, polyaniline having an acidic group is known. Polyaniline having an acidic group can exhibit conductivity without adding a dopant. Polyaniline having an acidic group can be obtained, for example, by polymerizing aniline having an acidic group via an oxidizing agent in the presence of a basic reaction auxiliary.

[0005] However, the polyaniline having acidic groups obtained in this way is not necessarily of high purity because it is obtained as a reaction mixture in which, in addition to the residual monomers, oligomers generated concurrently with side reactions, acidic substances (sulfate ions as decomposition products of monomers or oxidants, etc.), alkaline substances (ammonium ions as alkaline reaction aids, decomposition products of oxidants, etc.) and other by-products are mixed.

[0006] Furthermore, when polyaniline with acidic groups is used in chemically amplified resists, acidic and alkaline substances tend to migrate into the resist layer during exposure, PEB treatment, and development when a conductive film is formed on the resist layer. This can cause changes in pattern shape and sensitivity, affecting the resist layer. Specifically, when the resist layer is positive, if the acidic substance migrates from the conductive film to the resist layer, the unexposed portion of the resist layer will dissolve during development, resulting in film loss of the resist layer, pattern thinning, and sensitivity shift toward a higher sensitivity side. On the other hand, when the alkaline substance migrates from the conductive film to the resist layer, the acid in the exposed portion is deactivated, causing changes in the pattern shape and a shift in sensitivity toward a lower sensitivity side. Furthermore, when the resist layer is a negative type, the migration of the above-mentioned by-products from the conductive film to the resist layer will cause opposite phenomena.

[0007] Therefore, a conductive composition having excellent conductivity and little film loss of a resist layer has been proposed. For example, Patent Document 1 discloses a conductive composition containing a conductive polymer having an acidic group and a basic compound such as tetrabutylammonium hydroxide. Prior art literature Patent Literature

[0008] Patent Document 1: International Publication No. 2014 / 017540 Summary of the Invention Problems to be Solved by the Invention

[0009] In recent years, with the trend toward miniaturization of semiconductor devices, management of resist shapes on a scale of several nanometers has become increasingly necessary. Therefore, as an antistatic agent applicable also to the next generation process of semiconductor devices, there is a need for a conductive composition capable of forming a conductive film with smooth surface, that is, less surface roughness, which is also adaptable to more complex and fine pattern shapes. However, the conductive film formed from the conductive composition described in Patent Document 1 does not necessarily satisfy surface smoothness.

[0010] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a conductive composition capable of forming a conductive film having less film loss of a resist layer and excellent surface smoothness and conductivity. Means for solving problems

[0011] The present invention has the following embodiments. [1] A conductive composition comprising: a conductive polymer (A) having an acidic group; and a basic compound (B) having a cyclic amide and an amino group in the molecule. [2] The conductive composition according to [1], wherein the cyclic amide is a lactam. [3] The conductive composition according to [1] or [2], wherein the basic compound (B) is a compound represented by the following general formula (1).

[0012]

Chemical Formula 1

[0013] In formula (1), R 1 represents a linear or branched alkylene group having 1 to 10 carbon atoms, R 2 、R 3 Each independently represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, and p represents an integer of 1 to 4.

[0014] [4] The conductive composition according to any one of [1] to [3], further comprising: a nitrogen-containing heterocyclic compound (C) containing two or more nitrogen atoms in the molecule. [5] The conductive composition according to [4], wherein the mass ratio of the basic compound (B) to the nitrogen-containing heterocyclic compound (C) is: the basic compound (B): the nitrogen-containing heterocyclic compound (C) = 0.5:99.5 to 99.5:0.5. [6] The conductive composition according to any one of [1] to [5], further comprising a water-soluble polymer (D) (excluding the conductive polymer (A)). [7] A conductive film formed from the conductive composition according to any one of [1] to [6]. [8] A laminate comprising: a substrate; an electron beam resist layer formed on at least one surface of the substrate; and the conductive film of [7] formed on the electron beam resist layer. Effects of the Invention

[0015] According to the conductive composition of the present invention, a conductive film having less film loss of a resist layer and excellent surface smoothness and conductivity can be formed. DETAILED DESCRIPTION

[0016] Hereinafter, the present invention is described in detail. In addition, the term "conductivity" in the present invention refers to the conductivity of 1×10 11 Surface resistance values ​​below Ω / □. Surface resistance values ​​are determined from the potential difference between electrodes when a constant current flows. In this specification, "soluble" means that 0.1 g or more of the substance dissolves uniformly in 10 g (liquid temperature 25°C) of water alone, water containing at least one of a base and a basic salt, water containing an acid, or a mixture of water and a water-soluble organic solvent. Furthermore, "water-soluble" means, within the context of the above-mentioned solubility, solubility in water. In addition, in this specification, the "terminal" of the "terminal hydrophobic group" means a site other than the repeating unit constituting the polymer. In addition, in this specification, "mass average molecular weight" means the mass average molecular weight (in terms of sodium polystyrene sulfonate or polyethylene glycol) measured by gel permeation chromatography (GPC).

[0017] [Conductive composition] The conductive composition of the first embodiment of the present invention comprises a conductive polymer (A) and a basic compound (B) as described below. The conductive composition preferably further comprises at least one of a compound (C) as described below, a water-soluble polymer (D) (excluding the conductive polymer (A), and a solvent (E). Furthermore, the conductive composition may optionally comprise a polymer compound (F) and at least one of the optional components described below.

[0018] <Conductive polymer (A)> The conductive polymer (A) has an acidic group. When the conductive polymer (A) has an acidic group, the water solubility is improved. The conductive polymer having an acidic group is not particularly limited as long as it has at least one group selected from the group consisting of a sulfonic acid group and a carboxyl group in the molecule, and the effects of the present invention are achieved. However, from the viewpoint of solubility, for example, Japanese Patent Laid-Open Nos. 61-197633, 63-39916, 1-301714, 5-504153, 5-503953, 4-32848, 4-328181, 6-145 Conductive polymers described in Japanese Patent Application No. 386, Japanese Patent Application No. 6-56987, Japanese Patent Application No. 5-226238, Japanese Patent Application No. 5-178989, Japanese Patent Application No. 6-293828, Japanese Patent Application No. 7-118524, Japanese Patent Application No. 6-32845, Japanese Patent Application No. 6-87949, Japanese Patent Application No. 6-256516, Japanese Patent Application No. 7-41756, Japanese Patent Application No. 7-48436, Japanese Patent Application No. 4-268331, Japanese Patent Application No. 2014-65898, etc.

[0019] Specific examples of conductive polymers having acidic groups include π-conjugated conductive polymers in which the α-position or β-position is substituted with at least one group selected from the group consisting of a sulfonic acid group and a carboxyl group, and the π-conjugated conductive polymer contains as a repeating unit at least one selected from the group consisting of a phenylene vinylene group, a vinylene group, a thienylene group, a pyrrolylene group, a phenylene group, an iminophenylene group, an isothianaphtene group, a furylene group, and a carbazolylene group. In addition, when the π-conjugated conductive polymer includes a repeating unit of at least one type selected from the group consisting of an iminophenylene group and a carbazolylene group, a conductive polymer having at least one group selected from the group consisting of a sulfonic acid group and a carboxyl group on the nitrogen atom of the repeating unit, or a conductive polymer having an alkyl group substituted with at least one group selected from the group consisting of a sulfonic acid group and a carboxyl group or an alkyl group containing an ether bond on the nitrogen atom. Among these, from the viewpoint of conductivity and solubility, it is preferred to use a conductive polymer having as a monomer unit (unit) at least one selected from the group consisting of a thienylene group, a pyrrolylene group, an aminophenylene group, a phenylene vinylene group, a carbazolylene group, and an isothianaphthene group, in which the β-position is substituted with at least one group selected from the group consisting of a sulfonic acid group and a carboxyl group.

[0020] From the viewpoint of conductivity and solubility, the conductive polymer (A) preferably has at least one monomer unit selected from the group consisting of units represented by the following general formulae (2) to (5).

[0021]

Chemical Formula 2

[0022]

Chemical Formula 3

[0023]

Chemical Formula 4

[0024]

Chemical Formula 5

[0025] In formulas (2) to (5), X represents a sulfur atom or a nitrogen atom, and R 4 ~R 18 Each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 24 carbon atoms, a linear or branched alkoxy group having 1 to 24 carbon atoms, an acidic group, a hydroxyl group, a nitro group, a halogen atom (-F, -Cl, -Br or I), -N(R 19 2. NHCOR 19 、-SR 19 、-OCOR19 、-COOR 19 、-COR 19 , -CHO or -CN. R 19 It represents an alkyl group having 1 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, or an aralkyl group having 7 to 24 carbon atoms. Among them, R in general formula (2) 4 、R 5 At least one of the following, R in the general formula (3) 6 ~R 9 At least one of the following, R of the general formula (4) 10 ~R 13 At least one of the following, R of the general formula (5) 14 ~R 18 At least one of them is an acidic group or a salt thereof.

[0026] Here, the "acidic group" means a sulfonic acid group (sulfo group) or a carboxylic acid group (carboxyl group). The sulfonic acid group can be contained in the acid state (-SO3H) or in the ion state (-SO3 - ) is contained. Furthermore, the sulfonic acid group also includes a substituent having a sulfonic acid group (-R 20 SO3H). On the other hand, the carboxylic acid group may be contained in the acid state (-COOH) or in the ion state (-COO - ) is contained. Furthermore, the carboxylic acid group also includes a substituent having a carboxylic acid group (-R 20 COOH). The R 20 It represents a linear or branched alkylene group having 1 to 24 carbon atoms, a linear or branched arylene group having 6 to 24 carbon atoms, or a linear or branched aralkylene group having 7 to 24 carbon atoms.

[0027] Examples of the salt of the acidic group include alkali metal salts, alkaline earth metal salts, ammonium salts, and substituted ammonium salts of a sulfonic acid group or a carboxylic acid group. Examples of the alkali metal salt include lithium sulfate, lithium carbonate, lithium hydroxide, sodium sulfate, sodium carbonate, sodium hydroxide, potassium sulfate, potassium carbonate, potassium hydroxide, and derivatives having these skeletons. Examples of the alkaline earth metal salt include magnesium salt and calcium salt. Examples of the substituted ammonium salt include aliphatic ammonium salts, saturated alicyclic ammonium salts, and unsaturated alicyclic ammonium salts. Examples of the aliphatic ammonium salt include methylammonium, dimethylammonium, trimethylammonium, ethylammonium, diethylammonium, triethylammonium, methylethylammonium, diethylmethylammonium, dimethylethylammonium, propylammonium, dipropylammonium, isopropylammonium, diisopropylammonium, butylammonium, dibutylammonium, methylpropylammonium, ethylpropylammonium, methylisopropylammonium, ethylisopropylammonium, methylbutylammonium, ethylbutylammonium, tetramethylammonium, tetrahydroxymethylammonium, tetraethylammonium, tetra-n-butylammonium, tetra-sec-butylammonium, and tetra-tert-butylammonium. Examples of the saturated alicyclic ammonium salt include piperidinium, pyrrolidinium, morpholinium, piperazinium, and derivatives having these skeletons. Examples of the unsaturated alicyclic ammonium salt include pyridinium, α-pyridinium, β-pyridinium, γ-pyridinium, quinolinium, isoquinolinium, pyrrolium, and derivatives having these skeletons.

[0028] The conductive polymer (A) preferably has a unit represented by the above-mentioned general formula (5) from the viewpoint of exhibiting high conductivity. Among these, it is more preferable to have a monomer unit represented by the following general formula (6) from the viewpoint of excellent solubility.

[0029]

Chemical Formula 6

[0030] In formula (6), R 21 ~R 24 Each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 24 carbon atoms, a linear or branched alkoxy group having 1 to 24 carbon atoms, an acidic group, a hydroxyl group, a nitro group, or a halogen atom (-F, -Cl, -Br, or I). 21 ~R 24 At least one of them is an acidic group or a salt thereof.

[0031] As the unit represented by the general formula (6), the following unit is preferred from the viewpoint of easy production: R 21 ~R 24 Any one of them is a linear or branched alkoxy group having 1 to 4 carbon atoms, any one of the others is a sulfonic acid group, and the rest are hydrogen.

[0032] In the conductive polymer (A), from the viewpoint of achieving very good solubility, the number of aromatic rings to which acidic groups are bonded relative to the total number of aromatic rings in the polymer is preferably 50% or more, more preferably 70% or more, further preferably 90% or more, and most preferably 100%. The number of aromatic rings to which the acidic group is bonded relative to the total number of aromatic rings in the polymer is a value calculated from the charge ratio of the monomers when producing the conductive polymer (A).

[0033] Furthermore, in the conductive polymer (A), from the viewpoint of imparting reactivity to the monomer, the substituent other than the acidic group on the aromatic ring of the monomer unit is preferably an electron-donating group, specifically, an alkyl group having 1 to 24 carbon atoms, an alkoxy group having 1 to 24 carbon atoms, a halogen group (-F, -Cl, -Br or I), etc. are preferred. Among these, an alkoxy group having 1 to 24 carbon atoms is most preferred from the viewpoint of electron-donating property.

[0034] As the conductive polymer (A), from the viewpoint of exhibiting high conductivity and solubility, a compound having a structure represented by the following general formula (7) is preferred. Among the compounds having a structure represented by the following general formula (7), poly(2-sulfo-5-methoxy-1,4-iminophenylene) is particularly preferred.

[0035]

Chemical Formula 7

[0036] In formula (7), R 25 ~R 40 Each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, an acidic group, a hydroxyl group, a nitro group, or a halogen atom (-F, -Cl, -Br, or I). 25 ~R 40 At least one of the groups is an acidic group or a salt thereof. In addition, n represents the degree of polymerization. In the present invention, n is preferably an integer of 5 to 2500.

[0037] From the viewpoint of improving conductivity, it is desirable that at least a part of the acidic groups contained in the conductive polymer (A) be in the free acid form.

[0038] The weight average molecular weight of the conductive polymer (A), calculated as sodium polystyrene sulfonate by GPC, is preferably 1,000 to 1,000,000, more preferably 1,500 to 800,000, even more preferably 2,000 to 500,000, and particularly preferably 2,000 to 100,000, from the viewpoints of conductivity, solubility, and film-forming properties. When the weight average molecular weight of the conductive polymer (A) is less than 1,000, while solubility is excellent, conductivity and film-forming properties may be insufficient. On the other hand, when the weight average molecular weight exceeds 1,000,000, while conductivity is excellent, solubility may be insufficient. Here, "film-forming property" refers to the property of forming a uniform film without cissing or the like, and can be evaluated by a method such as spin coating on glass.

[0039] As a method for producing the conductive polymer (A), a known method can be used, and there are no particular limitations as long as the effects of the present invention are achieved. Specifically, there can be mentioned a method of polymerizing a polymerizable monomer (raw material monomer) having any of the aforementioned monomer units by various synthesis methods such as chemical oxidation and electrolytic oxidation. As such a method, for example, the synthesis methods described in Japanese Patent Laid-Open No. 7-196791 and Japanese Patent Laid-Open No. 7-324132 can be applied. Hereinafter, an example of a method for producing the conductive polymer (A) will be described.

[0040] The conductive polymer (A) can be obtained, for example, by polymerizing raw material monomers using an oxidizing agent in the presence of a basic reaction auxiliary. Examples of the alkaline reaction auxiliary include inorganic bases (sodium hydroxide, potassium hydroxide, lithium hydroxide, etc.), ammonium, aliphatic amines, cyclic saturated amines, and cyclic unsaturated amines. Examples of the oxidizing agent include peroxodisulfuric acids (peroxodisulfuric acid, ammonium peroxodisulfate, sodium peroxodisulfate, potassium peroxodisulfate, etc.), hydrogen peroxide, and the like.

[0041] Examples of the polymerization method include a method of dripping a mixed solution of a raw material monomer and an alkaline reaction auxiliary into an oxidant solution, a method of dripping an oxidant solution into a mixed solution of a raw material monomer and an alkaline reaction auxiliary, and a method of simultaneously dripping a mixed solution of a raw material monomer and an alkaline reaction auxiliary and an oxidant solution into a reaction vessel.

[0042] After the polymerization, the solvent is usually separated by filtration using a filter such as a centrifugal separator. The filtrate is then washed with a washing liquid as needed and then dried to obtain a conductive polymer (A).

[0043] The conductive polymer (A) thus obtained may contain low molecular weight substances such as raw material monomers (unreacted monomers), oligomers accompanying concurrent side reactions, oxidants, and alkaline reaction aids. These low molecular weight substances may hinder conductivity.

[0044] Therefore, it is preferable to purify the conductive polymer (A) to remove low molecular weight substances. The method for purifying the conductive polymer (A) is not particularly limited, and any method such as ion exchange, acid washing in a protonic acid solution, removal by heat treatment, neutralization and precipitation can be used. However, the ion exchange method is particularly effective from the perspective of easily obtaining a highly pure conductive polymer (A).

[0045] Examples of the ion exchange method include column and batch treatments using ion exchange resins such as cation exchange resins and anion exchange resins; and electrodialysis. When the conductive polymer (A) is purified by an ion exchange method, it is preferred that the reaction mixture obtained by polymerization is dissolved in an aqueous medium to a desired solid content concentration, and the resulting polymer solution is brought into contact with an ion exchange resin. Examples of the aqueous medium include water, organic solvents, and mixed solvents of water and organic solvents. Examples of the organic solvent include the same solvents as those described below as solvent (E). The concentration of the conductive polymer (A) in the polymer solution is preferably 0.1 to 20% by mass, more preferably 0.1 to 10% by mass, from the viewpoint of industrial efficiency and purification efficiency.

[0046] The content of the conductive polymer (A) is preferably 5 to 90 parts by mass, more preferably 10 to 80 parts by mass, and even more preferably 20 to 75 parts by mass, based on 100 parts by mass of the total amount of the conductive polymer (A), the basic compound (B), the compound (C), and the water-soluble polymer (D). When the content of the conductive polymer (A) is within this range, a conductive coating film (hereinafter referred to as a "conductive film") having even better conductivity can be formed.

[0047] <Basic compound (B)> The basic compound (B) has a cyclic amide and an amino group in the molecule. As the cyclic amide, lactam is preferred. As such a basic compound (B), a compound represented by the following general formula (1) is preferred.

[0048]

Chemical Formula 8

[0049] In formula (1), R 1 represents a linear or branched alkylene group having 1 to 10 carbon atoms, R 2 、R 3 Each independently represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, and p represents an integer of 1 to 4.

[0050] R 1 The number of carbon atoms in the alkyl group is preferably 1-7, more preferably 2-5. Preferred R 2 、R 3 At least one of them is a hydrogen atom, more preferably R 2 and R 3 Both are hydrogen atoms.

[0051] Examples of the compound represented by the general formula (1) include 1-(3-aminopropyl)-2-pyrrolidone and N-(3-aminopropyl)-ε-caprolactam. These compounds may be used alone or in combination of two or more at any ratio.

[0052] When the total amount of the conductive polymer (A), the basic compound (B), the compound (C) and the water-soluble polymer (D) is set to 100 parts by mass, the content of the basic compound (B) is preferably 1 to 70 parts by mass, more preferably 5 to 60 parts by mass, and further preferably 10 to 50 parts by mass. If the content of the basic compound (B) is above the above lower limit, when forming a conductive film on a resist layer using the conductive composition of the first embodiment of the present invention, it is possible to fully suppress the diffusion of acidic substances from the conductive film to the resist layer caused by heating. In addition, the surface smoothness of the conductive film is further improved. On the other hand, if the content of the basic compound (B) is below the above upper limit, the performance of the conductive film, i.e., the performance of conductivity and coating properties, can be maintained.

[0053] <Compound (C)> The compound (C) is a nitrogen-containing heterocyclic compound containing two or more nitrogen atoms in the molecule. The compound (C) is not particularly limited as long as it contains two or more nitrogen atoms in the molecule and has a nitrogen-containing heterocyclic structure, and has the effects of the present invention. However, compounds having a boiling point of 120° C. or higher are preferred.

[0054] Examples of compound (C) include pyridine derivatives having a tertiary amino group as a substituent, such as 4-dimethylaminopyridine, 4-dimethylaminomethylpyridine, and 3,4-bis(dimethylamino)pyridine; 1,5-diazabicyclo[4.3.0]-5-nonene (DBN), 1,8-diazabicyclo[5.4.0]-7-undecene (DBU), and derivatives thereof. Among these, 4-dimethylaminopyridine, 4-dimethylaminomethylpyridine, 1,5-diazabicyclo[4.3.0]-5-nonene (DBN), and 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) are preferred due to their excellent water solubility. These compounds (C) may be used alone or in combination of two or more at any ratio.

[0055] When the total amount of the conductive polymer (A), the basic compound (B), the compound (C), and the water-soluble polymer (D) is 100 parts by mass, the content of the compound (C) is preferably 1 to 65 parts by mass, more preferably 1 to 60 parts by mass, and even more preferably 2 to 50 parts by mass. If the content of the compound (C) is above the lower limit, the diffusion of the acidic substance from the conductive film to the resist layer can be more effectively suppressed. On the other hand, if the content of the compound (C) is below the upper limit, the conductivity of the conductive film is further improved.

[0056] The mass ratio of the basic compound (B) to the compound (C) is preferably 0.5:99.5 to 100:0, more preferably 2:98 to 100:0, even more preferably 5:95 to 100:0, and particularly preferably 60:40 to 100:0. On the other hand, the mass ratio of the basic compound (B) to the compound (C) is preferably 0.5:99.5 to 99.5:0.5. When the mass ratio of the basic compound (B) to the compound (C) is within this range, an excellent balance is achieved between suppressing film loss of the resist layer and improving the surface smoothness of the conductive film.

[0057] <Water-soluble polymer (D)> The water-soluble polymer (D) is a polymer excluding the conductive polymer (A). The water-soluble polymer (D) preferably has a nitrogen-containing functional group and a terminal hydrophobic group in the molecule from the viewpoint of easily exhibiting surface activity, easily suppressing the influence on the resist layer, and improving the surface smoothness of the conductive film. As the nitrogen-containing functional group, an amide group is preferred from the viewpoint of solubility.

[0058] The number of carbon atoms in the terminal hydrophobic group is preferably 4 or more, more preferably 8 or more. The terminal hydrophobic group is preferably a group containing an alkyl chain, an aralkyl chain, or an aryl chain within the hydrophobic group. From the viewpoint of solubility and surface activity, it is preferably a group containing at least one selected from the group consisting of an alkyl chain having 4 to 100 carbon atoms, an aralkyl chain having 7 to 100 carbon atoms, and an aryl chain having 6 to 100 carbon atoms. The number of carbon atoms in each of these alkyl chains, aralkyl chains, and aryl chains is preferably 4, 6, or 7 to 70, more preferably 8 to 30. Specific examples of such terminal hydrophobic groups include alkyl groups, aralkyl groups, aryl groups, alkoxy groups, aralkyloxy groups, aryloxy groups, alkylthio groups, aralkylthio groups, arylthio groups, primary or secondary alkylamino groups, aralkylamino groups, and arylamino groups. Among these, alkylthio groups, aralkylthio groups, and arylthio groups are preferred from the viewpoints of solubility and surface activity, and alkylthio groups are particularly preferred.

[0059] As the water-soluble polymer (D), the following compounds are preferred: compounds having a homopolymer of a vinyl monomer having an amide bond, or a copolymer of a vinyl monomer having an amide bond and a vinyl monomer not having an amide bond (other vinyl monomer) as the main chain structure, and having a hydrophobic group at a position other than the repeating unit constituting the polymer.

[0060] Examples of vinyl monomers having an amide bond include acrylamide and its derivatives, and N-vinyl lactam. Specifically, examples include acrylamide, N,N-dimethylacrylamide, N-isopropylacrylamide, N,N-diethylacrylamide, N,N-dimethylaminopropylacrylamide, tert-butylacrylamide, diacetoneacrylamide, N,N'-methylenebisacrylamide, N-vinyl-N-methylacrylamide, N-vinylpyrrolidone, and N-vinylcaprolactam. Among these, acrylamide, N-vinylpyrrolidone, and N-vinylcaprolactam are particularly preferred from the perspective of solubility.

[0061] The method for introducing the terminal hydrophobic group into the water-soluble polymer (D) is not particularly limited as long as the effects of the present invention are achieved. However, a method of introducing the terminal hydrophobic group by selecting a chain transfer agent during vinyl polymerization is preferred due to its simplicity. For example, a water-soluble polymer (D) having a nitrogen-containing functional group and a terminal hydrophobic group having 4 or more carbon atoms in the molecule can be produced by polymerizing a vinyl monomer having an amide bond and, if necessary, other vinyl monomers in the presence of a polymerization initiator and a chain transfer agent having 4 or more carbon atoms. In this case, the chain transfer agent is not particularly limited as long as it can introduce the above-mentioned terminal hydrophobic group, as long as it can achieve the effects of the present invention. However, thiols, disulfides, thioethers, etc., such as alkylthio groups, aralkylthio groups, and arylthio groups, which can easily provide preferred terminal hydrophobic groups, are preferably used.

[0062] The degree of polymerization of the repeating unit of the main chain structure of the water-soluble polymer (D), i.e., the vinyl monomer having an amide bond, is preferably 2 to 100,000, more preferably 2 to 1,000, and particularly preferably 3 to 200, from the viewpoint of solubility of the water-soluble polymer (D). Furthermore, from the viewpoint of surface activity, the ratio of the molecular weight of the main chain structure portion of the water-soluble polymer (D) (hereinafter sometimes referred to as "molecular weight of the water-soluble portion") to the molecular weight of the terminal hydrophobic portion (hereinafter sometimes referred to as "molecular weight of the hydrophobic portion"), i.e., (molecular weight of the water-soluble portion) / (molecular weight of the hydrophobic portion), is preferably 1 to 1500, more preferably 5 to 1000. Here, the "molecular weight of the water-soluble portion" and the "molecular weight of the hydrophobic portion" can be calculated from the mass average molecular weight of the obtained water-soluble polymer (D) and the charge ratio of the monomer constituting the main chain structure portion to the chain transfer agent constituting the terminal hydrophobic portion.

[0063] The mass average molecular weight of the water-soluble polymer (D) is preferably 1 to 1,000,000, more preferably 1 to 100,000, further preferably 600 or more and less than 2,000, and particularly preferably 600 to 1,800, calculated as polyethylene glycol by GPC. If the mass average molecular weight of the water-soluble polymer (D) is above the above lower limit, it becomes easy to show an effect of improving the coating properties of the conductive composition. On the other hand, if the mass average molecular weight of the water-soluble polymer (D) is below the above upper limit, the water solubility of the conductive composition is improved. In particular, if the mass average molecular weight of the water-soluble polymer (D) is 600 or more and less than 2,000, the balance between practical solubility in water and coating properties is excellent.

[0064] As the water-soluble polymer (D), from the viewpoint of solubility and the like, a compound represented by the following general formula (8) is preferred.

[0065]

Chemical Formula 9

[0066] In formula (8), R 41 、R 42 Each independently represents an alkylthio group, an aralkylthio group, an arylthio group or a hydrocarbon group. 41 、R 42 At least one of them is an alkylthio group, an aralkylthio group, or an arylthio group. m represents an integer of 2 to 100,000. Examples of the hydrocarbon group include a linear or branched alkyl group having 1 to 20 carbon atoms, a linear or branched alkenyl group having 2 to 20 carbon atoms, and a linear or branched alkynyl group having 2 to 20 carbon atoms.

[0067] When the total amount of the conductive polymer (A), the basic compound (B), the compound (C), and the water-soluble polymer (D) is 100 parts by mass, the content of the water-soluble polymer (D) is preferably 5 to 80 parts by mass, more preferably 10 to 70 parts by mass, and even more preferably 10 to 65 parts by mass. When the content of the water-soluble polymer (D) is within this range, the coating properties of the conductive composition on the resist layer are further improved. Furthermore, film loss of the resist layer can be further suppressed while further improving the surface smoothness of the conductive film.

[0068] Solvent (E) The solvent (E) is not particularly limited as long as it can dissolve the conductive polymer (A), the basic compound (B), the compound (C), and the water-soluble polymer (D), and can exhibit the effects of the present invention. Examples include water and a mixed solvent of water and an organic solvent. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropanol, propanol, and butanol; ketones such as acetone and ethyl isobutyl ketone; ethylene glycols such as ethylene glycol and ethylene glycol methyl ether; propylene glycols such as propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol butyl ether, and propylene glycol propyl ether; amides such as dimethylformamide and dimethylacetamide; pyrrolidones such as N-methylpyrrolidone and N-ethylpyrrolidone; and the like. When a mixed solvent of water and an organic solvent is used as the solvent (E), the mass ratio (water / organic solvent) thereof is preferably 1 / 100 to 100 / 1, more preferably 2 / 100 to 100 / 2.

[0069] <Polymer compound (F)> The conductive composition of the first embodiment of the present invention may contain a polymer compound (F) as needed for the purpose of further improving the coating film strength and surface smoothness. Specific examples of the polymer compound (F) include polyvinyl alcohol derivatives such as polyvinyl formal and polyvinyl butyral, polyacrylamides such as polyacrylamide, poly(N-tert-butylacrylamide), and polyacrylamide methylpropanesulfonic acid, polyvinyl pyrrolidone, polyacrylic acids, water-soluble alkyd resins, water-soluble melamine resins, water-soluble urea resins, water-soluble phenolic resins, water-soluble epoxy resins, water-soluble polybutadiene resins, water-soluble acrylic resins, water-soluble urethane resins, water-soluble acrylic styrene copolymer resins, water-soluble vinyl acetate acrylic copolymer resins, water-soluble polyester resins, water-soluble styrene maleic acid copolymer resins, water-soluble fluororesins, and copolymers thereof.

[0070] <Optional ingredients> Furthermore, the conductive composition of the first embodiment of the present invention may contain various additives such as pigments, defoaming agents, ultraviolet absorbers, antioxidants, heat resistance improvers, leveling agents, anti-sagging agents, matting agents, and preservatives as needed.

[0071] <Manufacturing method> The conductive composition of the first embodiment of the present invention can be obtained, for example, by mixing a basic compound (B), optionally a compound (C), a water-soluble polymer (D), a polymer compound (F), and at least one of the optional components into a solution of a conductive polymer (A). It is generally preferred to maintain the solution of the conductive polymer (A) at room temperature while adding the basic compound (B) and the like while stirring. Furthermore, the solution may be further diluted with a solvent (E) as needed. In the present invention, "room temperature" refers to 25°C.

[0072] Effects As described above, when a conductive film is formed on a resist layer, if acidic substances such as sulfates, which are monomers or decomposition products of oxidants, migrate from the conductive film to the resist layer, this can easily lead to pattern thinning, film loss, or a shift in sensitivity toward higher sensitivity when the resist is positive-tone. Conversely, when the resist is negative-tone, the pattern shape can be altered and the sensitivity can shift toward lower sensitivity. Furthermore, there is also a concern that the acidic groups released from the conductive polymer (A) may migrate to the resist side due to heating during formation of the conductive film.

[0073] However, according to the conductive composition of the first embodiment of the present invention, since it contains the conductive polymer (A) and the basic compound (B), the basic compound (B) reacts with the monomer and the sulfate to easily form a stable salt. As a result, the migration of acidic substances from the conductive film to the resist layer is suppressed. Furthermore, it is believed that the basic compound (B) effectively acts on the acidic groups in the conductive polymer (A), thereby improving the stability of the conductive polymer (A). Here, effectively acting on the acidic groups in the conductive polymer (A) means being able to stably neutralize them due to its high boiling point and strong alkalinity. As a result, the generation of acidic substances caused by destabilization of the acidic groups contained in the conductive polymer (A) in the conductive film is suppressed, and the migration of acidic substances from the conductive film to the resist layer is also suppressed. Therefore, in particular, in a patterning method using a charged particle beam using a chemically amplified resist, migration of acidic substances from the conductive film to the resist layer is suppressed, and the influence of film loss of the resist layer can be suppressed.

[0074] Furthermore, when the basic compound (B) is used, a conductive film having excellent surface smoothness and conductivity can be formed. In particular, when the conductive composition further contains the compound (C) described above, the conductivity of the conductive film is further improved. Furthermore, since the water-soluble polymer (D) contains no acid or base and is unlikely to produce byproducts upon hydrolysis, it can improve the coating properties of the conductive composition without adversely affecting the resist layer. Therefore, if the conductive composition further contains a water-soluble polymer (D), the effects of resist layer film loss, etc., can be further suppressed. Furthermore, the surface smoothness of the conductive film can be further improved.

[0075] The conductive composition of the first embodiment of the present invention can form a conductor having an insoluble or removable soluble coating film (conductive film) by heating after the conductor is formed. Therefore, it has the advantage of being applicable to both permanent antistatic films and temporary antistatic films used in industrial processes.

[0076] [Conductive film] The conductive film of the second embodiment of the present invention is formed from the conductive composition of the first embodiment of the present invention described above. Hereinafter, an example of a method for manufacturing a conductive film will be described. The method for producing a conductive film of this embodiment includes the steps of applying the conductive composition of the first embodiment of the present invention on a substrate and drying the coating film (coating film forming step), and heating the dried coating film (heating step).

[0077] (Coating film forming step) The coating film forming step is a step of applying the conductive composition of the first embodiment of the present invention on a substrate and drying the resulting coating film. The substrate is not particularly limited as long as it has the effects of the present invention, and examples thereof include polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyolefin resins represented by polyethylene and polypropylene, molded products and films of various polymer compounds such as vinyl chloride, nylon, polystyrene, polycarbonate, epoxy resin, fluororesin, polysulfone, polyimide, polyurethane, phenolic resin, silicone resin, and synthetic paper, paper, iron, glass, quartz glass, various wafers, aluminum, copper, zinc, nickel, stainless steel, and substances obtained by coating the surfaces of these substrates with various coatings, photosensitive resins, resists, and the like. The shape of the substrate is not particularly limited and may be a plate or a shape other than a plate.

[0078] The conductive composition is preferably applied on a substrate so that the thickness of the coating film after drying becomes 5 to 30 nm. The method for coating the conductive composition on the substrate is not particularly limited as long as it can achieve the effects of the present invention, and examples thereof include spin coating, spray coating, dip coating, roll coating, gravure coating, reverse roll coating, roll brush coating, air knife coating, curtain coating, and the like.

[0079] The step of coating the conductive composition on the substrate may be performed before or during the manufacturing steps of the substrate, such as uniaxial stretching, biaxial stretching, forming, or embossing, or may be performed after these treatment steps are completed. Furthermore, the conductive composition can be repeatedly applied onto the above-mentioned substrate coated with various coating materials or photosensitive materials to form a coating film.

[0080] (Heating process) The heating step is a step of heating the dried coating film. From the viewpoint of conductivity, the heating temperature is preferably in the range of 40° C. to 250° C., more preferably in the range of 60° C. to 200° C. From the viewpoint of stability, the treatment time is preferably within 1 hour, more preferably within 30 minutes.

[0081] Alternatively, the coating film may be left standing at room temperature (25° C.) for 1 to 60 minutes (standing step) instead of the heating step.

[0082] [Conductor] The third embodiment of the present invention comprises a substrate and a conductive film formed by applying the conductive composition of the first embodiment of the present invention on at least a portion of the substrate. Examples of the substrate include the substrates exemplified above in the description of the conductive film according to the second embodiment of the present invention.

[0083] When the substrate is plate-shaped, the conductive film may be provided on the entire surface of one surface of the substrate, or may be provided on a portion of one surface of the substrate. Furthermore, the conductive film may be provided on at least a portion of another surface of the substrate. Furthermore, the conductive film may be provided on at least a portion of a side surface of the substrate. When the substrate has a shape other than a plate, the conductive film may be provided on the entire surface of the substrate or on a portion of the surface of the substrate.

[0084] The conductor can be obtained by forming a conductive film on a substrate. The specific production method is the same as the method for producing the conductive film of the second embodiment of the present invention. That is, the conductor can be produced through the above-described film formation step and heating step. The above-described standing step can also be performed instead of the heating step.

[0085] [Laminated body] A laminate according to a fourth aspect of the present invention includes a substrate, an electron beam resist layer (hereinafter sometimes simply referred to as a "resist layer") formed on at least one surface of the substrate, and a conductive film formed on the electron beam resist layer. Examples of the substrate include the substrates exemplified above in the description of the conductive film according to the second embodiment of the present invention. The conductive film is the conductive film of the second embodiment of the present invention.

[0086] Examples of the resist layer include a layer composed of a positive-type or negative-type chemically amplified resist. Positive chemically amplified resists are not particularly limited as long as they are electron beam-sensitive, and known materials can be used. Typically, a resist containing an acid generator that generates an acid upon electron beam irradiation and a polymer containing a structural unit having an acid-degradable group can be used.

[0087] Negative-type chemically amplified resists are not particularly limited as long as they are sensitive to electron beams, and known materials can be used. Resists containing an acid generator that generates acid upon electron beam irradiation, a polymer soluble in a developer, and a crosslinking agent can be used.

[0088] The laminate can be obtained by sequentially forming a resist layer and a conductive film on a substrate. The resist layer can be formed by a known method, for example, by applying an organic solvent solution of a positive or negative chemically amplified resist to one surface of the substrate and heating (prebaking) as needed to form a positive or negative resist layer. The conductive film can be formed by applying the conductive composition of the first embodiment of the present invention to the surface of the resist layer, drying to form a coating film, and then heat-treating the dried coating film. The specific production method is the same as the method for producing the conductive film of the second embodiment of the present invention. The aforementioned standing step may be performed in place of the heat treatment step.

[0089] Other aspects of the present invention are as follows. <1> A conductive composition comprising a conductive polymer (A) having an acidic group, a basic compound (B) having a cyclic amide and an amino group in its molecule, and optionally a nitrogen-containing heterocyclic compound (C) having two or more nitrogen atoms in its molecule. <2> The conductive composition according to <1>, wherein the cyclic amide is a lactam. <3> The conductive composition according to <1> or <2>, wherein the basic compound (B) is a compound represented by the general formula (1). <4> The conductive composition according to <3>, wherein the compound represented by the general formula (1) is 1-(3-aminopropyl)-2-pyrrolidone or N-(3-aminopropyl)-ε-caprolactam. <5> The conductive composition according to any one of <1> to <4>, wherein the mass ratio of the basic compound (B) to the nitrogen-containing heterocyclic compound (C) is the basic compound (B): the nitrogen-containing heterocyclic compound (C) = 0.5:99.5 to 100:0. <6> The conductive composition according to <5>, wherein the mass ratio of the basic compound (B) to the nitrogen-containing heterocyclic compound (C) is: the basic compound (B): the nitrogen-containing heterocyclic compound (C) = 5:95 to 100:0. <7> The conductive composition according to <6>, wherein the mass ratio of the basic compound (B) to the nitrogen-containing heterocyclic compound (C) is: the basic compound (B): the nitrogen-containing heterocyclic compound (C) = 60:40 to 100:0. <8> The conductive composition according to any one of <1> to <4>, wherein the mass ratio of the basic compound (B) to the nitrogen-containing heterocyclic compound (C) is: the basic compound (B): the nitrogen-containing heterocyclic compound (C) = 0.5:99.5 to 99.5:0.5. <9> The conductive composition according to <8>, wherein the mass ratio of the basic compound (B) to the nitrogen-containing heterocyclic compound (C) is: the basic compound (B): the nitrogen-containing heterocyclic compound (C) = 5:95 to 99.5:0.5. <10> The conductive composition according to <9>, wherein the mass ratio of the basic compound (B) to the nitrogen-containing heterocyclic compound (C) is: the basic compound (B): the nitrogen-containing heterocyclic compound (C) = 60:40 to 99.5:0.5. <11> The conductive composition according to any one of <1> to <10>, further comprising a water-soluble polymer (D) (excluding the conductive polymer (A)). <12> The conductive composition according to <11>, wherein the water-soluble polymer (D) is a compound represented by the general formula (8). <13> The conductive composition according to <11> or <12>, wherein the content of the water-soluble polymer (D) is 5 to 80 parts by mass, based on 100 parts by mass of the total of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D). <14> The conductive composition according to <13>, wherein the content of the water-soluble polymer (D) is 10 to 65 parts by mass, based on 100 parts by mass of the total of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D). <15> The conductive composition according to any one of <1> to <14>, wherein the conductive polymer (A) has a monomer unit represented by the general formula (6). <16> The conductive composition according to any one of <1> to <15>, wherein the content of the conductive polymer (A) is 5 to 90 parts by mass, when the total amount of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D) is 100 parts by mass. <17> The conductive composition according to <16>, wherein the content of the conductive polymer (A) is 20 to 75 parts by mass, based on 100 parts by mass of the total of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D). <18> The conductive composition according to any one of <1> to <17>, wherein the content of the basic compound (B) is 1 to 70 parts by mass, when the total amount of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D) is 100 parts by mass. <19> The conductive composition according to <18>, wherein the content of the basic compound (B) is 5 to 35 parts by mass, based on 100 parts by mass of the total of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D). <20> The conductive composition according to any one of <1> to <19>, wherein the nitrogen-containing heterocyclic compound (C) is one or more selected from the group consisting of 4-dimethylaminopyridine, 4-dimethylaminomethylpyridine, 1,5-diazabicyclo[4.3.0]-5-nonene, and 1,8-diazabicyclo[5.4.0]-7-undecene. <21> The conductive composition according to any one of <1> to <20>, wherein the content of the nitrogen-containing heterocyclic compound (C) is 1 to 65 parts by mass, when the total amount of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D) is 100 parts by mass. <22> The conductive composition according to <21>, wherein the content of the nitrogen-containing heterocyclic compound (C) is 1 to 10 parts by mass, based on 100 parts by mass of the total of the conductive polymer (A), the basic compound (B), the nitrogen-containing heterocyclic compound (C), and the water-soluble polymer (D). <23> The conductive composition according to any one of <1> to <22>, further comprising a solvent (E). <24> The conductive composition according to <23>, wherein the solvent (E) is water or a mixed solvent of water and an organic solvent. <25> The conductive composition according to <24>, wherein the organic solvent is one or more selected from the group consisting of methanol, ethanol, isopropyl alcohol, propanol, and butanol. <26> The conductive composition according to any one of <1> to <25>, which is used for antistatic application during charged particle beam drawing. <27> A conductive film formed from the conductive composition according to any one of <1> to <26>. <28> A conductor comprising: a substrate; and the conductive film according to <27> formed on at least a portion of the substrate. <29> A laminate comprising: a substrate; an electron beam resist layer formed on at least one surface of the substrate; and the conductive film according to <27> formed on the electron beam resist layer. [Example]

[0090] Hereinafter, the present invention will be described in more detail through examples, but the following examples are not intended to limit the scope of the present invention. In addition, various measurement and evaluation methods in Examples and Comparative Examples are as follows.

[0091] [Measurement and evaluation methods] <Evaluation of electrical conductivity> 1.3 mL of the conductive composition was dropped onto a 4-inch silicon wafer serving as a substrate, and spin-coated using a spin coater at 2000 rpm for 60 seconds to cover the entire surface of the substrate. Thereafter, the substrate was heated at 80°C for 2 minutes on a hot plate to form a conductive film having a thickness of approximately 20 nm, thereby obtaining a conductor. The surface resistance value [Ω / □] of the conductive film was measured by a two-terminal method (distance between electrodes: 20 mm) using Hiresta UX-MCP-HT800 (manufactured by Mitsubishi Chemical Analytech Co., Ltd.).

[0092] <Evaluation of surface smoothness> The same method as the evaluation of conductivity was carried out to produce a conductor. The arithmetic mean roughness (Ra) [nm] of the conductive film was measured using a probe profiler (Stylus profiler P-16+, manufactured by KLA-Tencor Corporation) under the following measurement conditions. (Measurement conditions) Stylus: 2μm R60° Acupuncture pressure: 0.03mg Scanning range: 500um Scanning speed: 2um / s

[0093] <Evaluation using membrane loss test> (Determination of membrane loss) Using a chemically amplified electron beam resist (for example, commercially available positive resist "FEP-171" manufactured by FUJIFILM Electronic Materials Co., Ltd., hereinafter referred to as "resist"), the film loss of the resist layer was measured according to the following procedures (1A) to (8A). (1A) Formation of a resist layer: A chemically amplified resist (0.2 μm) was spin-coated on a 4-inch silicon wafer serving as a substrate using a spin coater at 2000 rpm for 60 seconds, and then pre-baked on a hot plate at 130°C for 90 seconds to remove the solvent, thereby forming a resist layer on the substrate. (2A) Resist Layer Thickness Measurement 1: A portion of the resist layer formed on the substrate was peeled off, and the initial resist layer thickness a [nm] was measured using a probe profiler (Stylus profiler P-16+, manufactured by KLA-Tencor Corporation) with the substrate surface as a reference position. (3A) Formation of a conductive film: 2 mL of a conductive composition was added dropwise to the resist layer and spin-coated using a spin coater at 2000 rpm for 60 seconds to cover the entire surface of the resist layer. The film was then heated on a hot plate at 80°C for 2 minutes to form a conductive film with a thickness of approximately 30 nm on the substrate. (4A) Baking treatment: The substrate having the conductive film and the resist layer laminated thereon was heated on a hot plate at 120° C. for 20 minutes in air atmosphere, and then allowed to stand in air at room temperature (25° C.) for 90 seconds. (5A) Water washing: After washing the conductive film with 20 mL of water, the conductive film was spun at 2000 rpm for 60 seconds using a spin coater to remove water from the surface of the resist layer. (6A) Development: 20 mL of a developer consisting of a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution was added dropwise to the surface of the resist layer. After standing for 60 seconds, the resist layer was spun at 2000 rpm for 60 seconds using a spin coater to remove the developer from the surface of the resist layer. The resist layer was then dried while continuing to spin for 60 seconds. (7A) Resist layer thickness measurement 2: After peeling off a portion of the resist layer within 5 mm from the portion peeled off in (2A), the thickness b [nm] of the resist layer after development was measured using a probe step profiler. (8A) Calculation of film loss: The film loss c [nm] of the resist layer was calculated by subtracting the film thickness b from the above-mentioned film thickness a (c=ab).

[0094] (Determination of reference film loss) Each resist layer has a unique film loss amount (hereinafter referred to as "reference film loss amount") d [nm) due to storage after the resist layer is formed. This reference film loss amount d, which is not caused by the conductive film, is measured according to the following procedures (1B) to (6B). (1B) Formation of Resist Layer: A resist layer was formed on a substrate in the same manner as in (1A). (2B) Resist layer thickness measurement 1: The same method as in (2A) was carried out to measure the initial resist layer thickness a [nm]. (3B) Baking treatment: Baking treatment was performed in the same manner as in (4A) above except that a substrate on which a resist layer was laminated was used. (4B) Development: Development was performed in the same manner as in (6A). (5B) Resist layer thickness measurement 2: After peeling off a portion of the resist layer within 5 mm from the portion of the resist layer peeled off in (2B), the thickness e [nm] of the resist layer after development was measured using a probe step profiler. (6B) Calculation of film loss amount: The film thickness e is subtracted from the above-mentioned film thickness a to calculate a reference film loss amount d (d=ae) of the resist layer. In addition, the reference film loss amount d of the resist layer is 3 nm.

[0095] (Calculation of the amount of film loss of the resist layer caused by acidic substances) The film loss amount f [nm] of the resist layer caused by migration of the acidic substance from the conductive film to the resist layer is calculated by subtracting the reference film loss amount d of the resist layer from the film loss amount c of the resist layer (f=cd).

[0096] [Production of Conductive Polymer (A)] (Production Example 1: Production of Conductive Polymer (A-1)) 1 mol of 3-aminoanisole-4-sulfonic acid was dissolved in 300 mL of a 4 mol / L pyridine solution (solvent: water / acetonitrile = 3 / 7 (mass ratio)) at 0°C to obtain a monomer solution. Separately, 1 mol of ammonium peroxodisulfate was dissolved in 1 L of a solution of water / acetonitrile = 3 / 7 (mass ratio) to obtain an oxidizing agent solution. Next, the monomer solution was added dropwise while the oxidant solution was cooled to 5°C. After the addition was completed, the mixture was stirred at 25°C for 12 hours to obtain a conductive polymer. The reaction mixture containing the obtained conductive polymer was then filtered and separated using a centrifugal filter. The mixture was then washed with methanol and dried to obtain 185 g of a powdered conductive polymer (A-1).

[0097] (Manufacturing Example 2: Manufacturing of Conductive Polymer Solution (A1-1)) 23 g of the conductive polymer (A-1) obtained in Production Example 1 was dissolved in 980 g of pure water to obtain 1000 g of a conductive polymer solution (A-1-1) having a solid content concentration of 2% by mass. The column was filled with 500 mL of a cation exchange resin ("Amberlite IR-120B" manufactured by Organo Corporation) washed with ultrapure water. 1000 g of the conductive polymer solution (A-1-1) was passed through the column at a rate of 50 mL / min (SV=6) to obtain 900 g of the conductive polymer solution (A1-1-1) from which alkaline substances and the like were removed. Next, 500 mL of anion exchange resin ("Amberlite IRA410" manufactured by Organo Corporation) washed with ultrapure water was filled into the column. 900 g of the conductive polymer solution (A1-1-1) was passed through the column at a rate of 50 mL / min (SV=6) to obtain 800 g of the conductive polymer solution (A1-1) from which alkaline substances and the like were removed. Composition analysis of the conductive polymer solution (A1-1) by ion chromatography revealed that residual monomers had been removed by at least 80% by mass, sulfate ions had been removed by at least 99% by mass, and alkaline substances (pyridine) had been removed by at least 99% by mass. Furthermore, measurement of the residual component after heating revealed a value of 2.0% by mass. In other words, the solids concentration of the conductive polymer solution (A1-1) was 2.0% by mass. In addition, 1 Sverdrup (SV) is defined as 1×10 6 m 3 / s(1GL / s).

[0098] [Production of water-soluble polymer (D)] (Production Example 3: Production of Water-Soluble Polymer (D-1)) 55g of N-vinyl pyrrolidone as a vinyl monomer containing a nitrogen-containing functional group, 3g of azobisisobutyronitrile as a polymerization initiator, and 1g of n-dodecyl mercaptan as a chain transfer agent for introducing a terminal hydrophobic group were stirred and dissolved in 100mL of isopropanol as a solvent to obtain a reaction solution. Then, the reaction solution was added dropwise at a dropping rate of 1mL / min to 100mL of isopropanol preheated to 80°C to perform dropwise polymerization. While maintaining the temperature of isopropanol at 80°C, dropwise polymerization was performed. After the addition was completed, the mixture was further aged for 2 hours at 80°C and then allowed to cool. Then, the reaction mixture was concentrated under reduced pressure to dry the obtained reactant. 5.3 parts by mass of the dried polymer was dissolved in 95 parts by mass of water, cooled at 5°C for 24 hours, and filtered using a 30nm polyethylene filter to obtain a 5.0% by mass water-soluble polymer solution (D-1).

[0099] [Example 1] A conductive composition was prepared by mixing 25 parts by mass (0.5 parts by mass in terms of solid content) of the conductive polymer solution (A1-1), 0.21 parts by mass of 1-(3-aminopropyl)-2-pyrrolidone as a basic compound (B), 70.79 parts by mass of water, and 4 parts by mass of isopropyl alcohol (IPA). The obtained conductive composition was evaluated for conductivity and surface smoothness, and a film loss test was performed. The results are shown in Table 1.

[0100] [Examples 2 to 8] The components were mixed to form the mixed composition shown in Table 1 to prepare a conductive composition. The obtained conductive composition was evaluated for conductivity and surface smoothness, and a film loss test was performed. The results are shown in Table 1.

[0101] [Comparative Examples 1 and 2] A conductive composition was prepared in the same manner as in Example 1, except that tetrabutylammonium hydroxide (TBAH) in the amount shown in Table 2 was used instead of the basic compound (B). Various evaluations were performed. The results are shown in Table 2.

[0102]

Table 1

[0103]

Table 2

[0104] In Table 1, "(A) / ((A)+(B)+(C)+(D))" represents the content (parts by mass) of the conductive polymer (A) when the total of the conductive polymer (A), the basic compound (B), the compound (C), and the water-soluble polymer (D) is 100 parts by mass. The same applies to the contents of the basic compound (B), the compound (C), and the water-soluble polymer (D). "(B):(C)" represents the mass ratio of the basic compound (B) to the compound (C) (basic compound (B):compound (C)). In Table 2, "(A) / ((A)+(B)+(C)+(D)+TBAH)" represents the content (parts by mass) of the conductive polymer (A), given that the total of the conductive polymer (A), the basic compound (B), the compound (C), the water-soluble polymer (D), and TBAH is 100 parts by mass. The same applies to the contents of the basic compound (B), the compound (C), the water-soluble polymer (D), and TBAH. "(B):(C)" represents the mass ratio of the basic compound (B) to the compound (C) (basic compound (B):compound (C)).

[0105] In addition, the abbreviations in Tables 1 and 2 are as follows. B-1: 1-(3-aminopropyl)-2-pyrrolidone B-2: N-(3-aminopropyl)-ε-caprolactam C-1: 1,5-diazabicyclo[4.3.0]-5-nonene (DBN) ·TBAH: Tetrabutylammonium hydroxide IPA: Isopropyl alcohol

[0106] As apparent from Table 1, the conductive composition obtained in each example can form a conductive film with little film loss of the resist layer and excellent surface smoothness and conductivity. On the other hand, as can be seen from Table 2, the conductive films formed from the conductive compositions obtained in Comparative Examples 1 and 2 were inferior in surface smoothness and conductivity compared to those in the Examples. Industrial Applicability

[0107] The conductive composition of the present invention is useful as an antistatic agent applicable also to semiconductor devices of the next-generation process.

Claims

1. A conductive composition comprising: a conductive polymer A having an acidic group, a basic compound B having a cyclic amide and an amino group in its molecule, and a nitrogen-containing heterocyclic compound C containing two or more nitrogen atoms in its molecule. 2 . The conductive composition according to claim 1 , wherein the nitrogen-containing heterocyclic compound C containing two or more nitrogen atoms in a molecule has a boiling point of 120° C. or higher. 3 . The conductive composition according to claim 1 , wherein the mass ratio of the basic compound B to the nitrogen-containing heterocyclic compound C is: the basic compound B: the nitrogen-containing heterocyclic compound C=0.5:99.5 to 99.5:0.

5. The conductive composition according to claim 1 , further comprising a water-soluble polymer D, wherein the water-soluble polymer D does not include the conductive polymer A. The conductive composition according to claim 4 , wherein the water-soluble polymer D has a nitrogen-containing functional group and a terminal hydrophobic group in the molecule. 6 . The conductive composition according to claim 4 , wherein the ratio of (molecular weight of the water-soluble portion) / (molecular weight of the hydrophobic portion) of the water-soluble polymer D is 1 to 1500.

7. The conductive composition according to claim 1, further comprising a polymer compound F, wherein the polymer compound F is at least one selected from the group consisting of polyvinyl alcohol derivatives, polyacrylamides, polyvinyl pyrrolidone, polyacrylic acids, water-soluble alkyd resins, water-soluble melamine resins, water-soluble urea resins, water-soluble phenolic resins, water-soluble epoxy resins, water-soluble polybutadiene resins, water-soluble acrylic resins, water-soluble urethane resins, water-soluble acrylic acid styrene copolymer resins, water-soluble vinyl acetate acrylic acid copolymer resins, water-soluble polyester resins, water-soluble styrene maleic acid copolymer resins, water-soluble fluororesins, and copolymers thereof. 8 . A conductive film formed from the conductive composition according to claim 1 . 9 . A laminate comprising: a substrate; an electron beam resist layer formed on at least one surface of the substrate; and the conductive film according to claim 8 formed on the electron beam resist layer.

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