JP6383337B2 - Conductive polymer composition, coated article, pattern forming method, and substrate - Google Patents

Description

  The present invention relates to a conductive polymer composition containing a polyaniline-based conductive polymer, a coated article using the same, a pattern forming method, and a substrate. More specifically, the present invention relates to a conductive polymer composition suitably used for resist antistatic in lithography using ultraviolet rays, electron beams, etc., and an article provided with an antistatic film formed using the same. The present invention relates to a pattern forming method using the conductive polymer composition, and a substrate obtained by the pattern forming method.

  Conventionally, in a manufacturing process of a semiconductor element such as an IC or LSI, fine processing by a lithography method using a photoresist has been performed. This is a method of etching a substrate using a resist pattern obtained as a result of development processing with a solvent or the like as a mask by remarkably changing the solubility of the thin film by inducing a crosslinking or decomposition reaction of the thin film by light irradiation. . In recent years, with high integration of semiconductor elements, high-precision microfabrication using short-wavelength light has been required. Lithography using electron beams is being developed as a next generation technology because of its short wavelength characteristics.

  A problem peculiar to lithography using electron beams is a charging phenomenon (charge-up) during exposure. This is a phenomenon in which, when a substrate to be subjected to electron beam exposure is covered with an insulating resist film, charges are accumulated on the resist film or in the film. Due to this charging, the trajectory of the incident electron beam is bent, so that the drawing accuracy is significantly lowered. Therefore, an antistatic film applied on the electron beam resist has been studied.

In order to alleviate such a reduction in drawing accuracy, Patent Document 1 discloses a composition containing a composite composed of an aniline-based conductive polymer, a polyacid, and H ₂ O, and the aniline-based conductive polymer is disclosed. And a composite made of polyacid can be formed with a good spin coat film at 5 to 10% by mass, and a sufficient antistatic effect is recognized at a film thickness of 150 nm, and peeling and cleaning with H ₂ O are possible. It is clearly shown that an antistatic film is formed.

  However, when an antistatic film is provided on a chemically amplified resist, the acid generated by exposure is neutralized by the components in the antistatic film, and in the positive type, the resist exposed portion is insolubilized during development, and in the negative type In the positive type, the resist unexposed part is partially dissolved during development, and in the negative type, the resist unexposed part is partially developed during development. There were cases where changes in resist shape and fluctuations in sensitivity were observed, such as insolubilization.

  Since chemically amplified resists are not resistant to most organic solvents, many antistatic agents are provided on the resist. However, the surface of the chemically amplified resist is hydrophobic, and it is difficult to apply the water-based antistatic agent. Therefore, it is necessary to add a surfactant or the like. However, by adding a surfactant, a mixing layer is formed on the resist surface. Therefore, the influence of the acid generated in the resist after the drawing and the acid component in the antistatic film in the mixing layer is promoted, which causes problems such as a change in resist shape and sensitivity fluctuation.

  Patent Document 2 discloses a conductive composition containing a complex composed of an acidic group-substituted polyaniline-based conductive polymer and a basic compound, and is applicable to an electrolytic capacitor or the like. The improvement effect is clearly indicated.

US Pat. No. 5,370,825 JP 2014-15550 A JP 2008-133448 A JP 2010-77404 A

  In the composition described in Patent Document 1, since the acidity is high due to the presence of an acid derived from polyacid present in a complex composed of a polyaniline-based conductive polymer and polyacid, the antistatic effect is effective. However, there were unfavorable effects on lithography, such as changes in resist shape and sensitivity fluctuations.

The polyaniline-based conductive polymer in Patent Document 2 does not use a polyacid of another molecule as described in Patent Document 1, and is self-doped by introducing an acidic substituent into the aniline monomer that forms the conductive polymer. Type polyaniline-based conductive polymer, and the aniline-based conductive polymer and polyacid do not form a complex. Also, the acidic substituent on the aniline monomer is present in a 1: 1 ratio with the amino group of aniline. For these reasons, it is difficult to change the composition ratio of the aggregate due to the amino group and acidic substituent of the polyaniline-based conductive polymer in order to adapt to the application and purpose, and the hydrophilicity of the polymer, H ₂ Since the abundance ratio of acidic groups that are not involved in complex formation that greatly contributes to high dispersibility in O is limited, the polymer in the composition tends to re-aggregate and is charged on the chemically amplified resist. When applied as a protective film, there were problems such as the occurrence of defects.

  The present invention has been made in view of the above circumstances, is excellent in antistatic ability, does not adversely affect the resist, has excellent coating properties, and can be preferably used particularly in lithography using an electron beam or the like. An object is to provide a molecular composition.

（式中、Ｒ^Ａ１〜Ｒ^Ａ４はそれぞれ独立にヘテロ原子を有してもよい炭素数１〜２０の直鎖状、分岐状又は環状の１価炭化水素基、水素原子、ハロゲン原子のいずれかを示す。また、Ｒ^Ａ１とＲ^Ａ２、あるいはＲ^Ａ３とＲ^Ａ４は互いに結合して環を形成してもよい。） In order to solve the above problems, the present invention provides:
Provided is a conductive polymer composition containing a polyaniline-based conductive polymer (A) having a repeating unit represented by the following general formula (1), a polyanion (B), and a betaine compound (C).

(In the formula, R ^{A1 to} R ^A4 are each independently a linear, branched or cyclic monovalent hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom or a halogen atom which may have a hetero atom. R ^A1 and R ^A2 , or R ^A3 and R ^A4 may be bonded to each other to form a ring.)

  Such a conductive polymer composition has excellent antistatic ability, does not adversely affect the resist, and has excellent coating properties. Therefore, the conductive polymer composition can be suitably used for lithography using an electron beam or the like. It becomes a conductive polymer composition.

（式中、Ｒ^Ｂ１〜Ｒ^Ｂ３はそれぞれ独立に、ヘテロ原子で置換されていてもよく、ヘテロ原子が介在してもよい炭素数１〜２０の直鎖状、分岐状又は環状の１価炭化水素基、又は水素原子を示す。また、Ｒ^Ｂ１とＲ^Ｂ２、あるいはＲ^Ｂ１とＲ^Ｂ２とＲ^Ｂ３は互いに結合して式中のＡ^＋と共に環を形成してもよい。Ａ^＋はヘテロ原子であり、一価の陽イオンを示す。ｋは１〜８の整数を示す。Ｌは炭素原子又はヘテロ原子であり、ｋが２以上の場合、これらの両方を有していてもよい。Ｒ^Ｂ４、Ｒ^Ｂ５は水素原子、又はヘテロ原子が介在してもよい炭素数１〜２０の直鎖状、分岐状又は環状の１価炭化水素基を示す。また、Ｒ^Ｂ４とＲ^Ｂ５は互いに結合して環を形成してもよい。Ｂ⁻は一価のアニオン性官能基であり、カルボン酸イオン又はスルホン酸イオンを示す。） At this time, it is preferable that the component (C) is represented by the following general formula (2).

(In the formula, R ^{B1 to} R ^B3 are each independently substituted with a heteroatom, and a linear, branched or cyclic monovalent carbon atom having 1 to 20 carbon atoms in which the heteroatom may be interposed. Represents a hydrogen group or a hydrogen atom, and R ^B1 and R ^B2 , or R ^B1 , R ^B2 and R ^B3 may combine with each other to form a ring together with A ⁺ in the formula, where A ⁺ is a heteroatom. And represents a monovalent cation, k represents an integer of 1 to 8. L is a carbon atom or a hetero atom, and when k is 2 or more, it may have both of them. ^B4 and R ^{B5 each} represent a hydrogen atom or a linear, branched or cyclic monovalent hydrocarbon group having 1 to 20 carbon atoms that may be intervened by a hetero atom, and R ^B4 and R ^B5 are bonded to each other. may form a ring by .B ^- is an anionic functional group monovalent carboxylic acid It indicates on or sulfonic acid ion.)

  If the conductive polymer composition of the present invention contains the betaine compound represented by the general formula (2) as the component (C), the conductive polymer composition is used on a workpiece. When the antistatic film is formed, acid diffusion between the workpiece and the antistatic film is suppressed, and the influence of the acid can be mitigated.

（式中、Ｒ^Ｂ１〜Ｒ^Ｂ５、Ａ^＋、Ｌ、及びｋは、前記と同様である。） At this time, the component (C) is preferably represented by the following general formula (3).

(In the formula, R ^{B1 to} R ^B5 , A ⁺ , L, and k are the same as described above.)

  If the conductive polymer composition of the present invention contains the betaine compound represented by the general formula (3) as the component (C), the conductive polymer composition is used on a workpiece. When the antistatic film is formed, acid diffusion between the workpiece and the antistatic film is further suppressed, and the influence of the acid can be further alleviated.

（式中、Ｒ^１は水素原子又はメチル基であり、Ｒ^２は単結合、エステル基、あるいはエーテル基、エステル基のいずれか又はこれらの両方を有していてもよい炭素数１〜１２の直鎖状、分岐状、環状の炭化水素基のいずれかであり、Ｚはフェニレン基、ナフチレン基、エステル基のいずれかであり、ａは０＜ａ≦１．０である。） Moreover, it is preferable at this time that the said (B) component contains what is represented by following General formula (4).

(In the formula, R ¹ is a hydrogen atom or a methyl group, and R ² has a single bond, an ester group, an ether group, an ester group, or both of which may have 1 to 12 carbon atoms. (It is any one of a linear, branched, and cyclic hydrocarbon group, Z is any one of a phenylene group, a naphthylene group, and an ester group, and a is 0 <a ≦ 1.0.)

  If the conductive polymer composition of the present invention includes the component (B) represented by the general formula (4), the effects of the present invention can be further improved.

  Moreover, it is preferable at this time that content of the said (C) component is 1 mass part to 50 mass parts with respect to 100 mass parts of composite_body | complex of the said (A) component and the said (B) component.

  If the content of the component (C) is such, acid diffusion from the antistatic film formed by the conductive polymer composition to the resist layer is reduced, and the antistatic effect at the time of electron beam drawing is reduced. While being held, the influence of lithography on the lithography is reduced, and a high-resolution resist pattern can be obtained. Further, from the same effect, it is possible to obtain a resist workpiece with little sensitivity variation over time from film formation to pattern development.

  Moreover, it is preferable at this time that content of the said (C) component is 3 mass parts to 10 mass parts with respect to 100 mass parts of composite_body | complex of the said (A) component and the said (B) component.

  If the content of the component (C) is such, acid diffusion from the antistatic film formed by the conductive polymer composition to the resist layer is further reduced, and an antistatic effect at the time of electron beam drawing. In this way, the influence of the acid on the lithography is further reduced, and a resist pattern with higher resolution can be obtained. Further, from the same effect, it is possible to obtain a resist workpiece with less sensitivity variation over time from film formation to pattern development.

  At this time, it is preferable that the conductive polymer composition further contains a nonionic surfactant.

  If it is such, the wettability to workpieces, such as a base material, can be raised.

  Moreover, at this time, it is preferable that content of the said nonionic surfactant is 1 mass part to 50 mass parts with respect to 100 mass parts of composite_body | complex of the said (A) component and the said (B) component.

  In such a case, the wettability to the resist surface becomes better and the antistatic ability is sufficient.

The conductive polymer composition may be used for forming an antistatic film.
The present invention also provides a coated article provided with an antistatic film formed using the conductive polymer composition on a workpiece.

  The antistatic film formed from the conductive polymer composition of the present invention is excellent in antistatic ability. By coating such an antistatic film on various workpieces, a high quality coated product can be obtained. Can be obtained.

  At this time, the workpiece can be a substrate provided with a chemically amplified resist film.

  Since the conductive polymer composition of the present invention does not adversely affect the resist, it has been difficult to apply as a workpiece to be provided with an antistatic film formed from the conductive polymer composition of the present invention. It is also possible to select a substrate provided with a chemically amplified resist film.

  At this time, the workpiece can be a substrate for obtaining a resist pattern by pattern irradiation with an electron beam.

  Since the conductive polymer composition of the present invention can be suitably used particularly for lithography using an electron beam or the like, a resist pattern having high sensitivity, high resolution, and good pattern shape is obtained. be able to.

  Furthermore, the present invention provides a step of forming an antistatic film on the resist film of a substrate provided with a chemically amplified resist film using the conductive polymer composition, a step of pattern irradiation with an electron beam, and an alkaline developer. And a pattern forming method including a step of developing a resist pattern to obtain a resist pattern.

  According to such a pattern forming method, a charging phenomenon at the time of exposure can be prevented, and a resist pattern having high sensitivity, high resolution, and good pattern shape can be obtained.

  The present invention also provides a substrate having a resist pattern obtained by the pattern forming method.

  With the pattern forming method of the present invention, a substrate having a resist pattern having high sensitivity, high resolution, and good pattern shape can be obtained.

As described above, since the conductive polymer composition of the present invention is excellent in antistatic ability, it can be suitably used for antistatic applications. Moreover, a high quality coated article can be obtained by coating various workpieces with an antistatic film formed using the conductive polymer composition of the present invention.
In addition, even when the conductive polymer composition of the present invention is applied to a lithography method using a photoresist, it does not adversely affect resist insolubility and sensitivity fluctuations, and is excellent in coating properties. It is possible to obtain a resist pattern that has high sensitivity, high resolution, and good pattern shape.

Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited thereto.
As described above, in recent years, application of an antistatic film has also been studied in the manufacturing process of semiconductor elements. However, conventional conductive compositions and the like have a negative effect on the resist due to the acid contained in the composition. There was a problem.

  Therefore, as a result of intensive studies by the present inventors to solve the above problems, by using a betaine compound, the antistatic ability is excellent, the resist is not adversely affected, the coating property is excellent, and an electron beam is used. The present inventors have found that a conductive polymer composition that can be suitably used in conventional lithography can be obtained, and the present invention has been completed.

  That is, the conductive polymer composition of the present invention is characterized by containing a polyaniline-based conductive polymer, a polyanion, and a betaine compound.

（式中、Ｒ^Ａ１〜Ｒ^Ａ４はそれぞれ独立にヘテロ原子を有してもよい炭素数１〜２０の直鎖状、分岐状又は環状の１価炭化水素基、水素原子、ハロゲン原子のいずれかを示す。また、Ｒ^Ａ１とＲ^Ａ２、あるいはＲ^Ａ３とＲ^Ａ４は互いに結合して環を形成してもよい。） Hereinafter, the present invention will be described in more detail.
[(A) Polyaniline-based conductive polymer]
The conductive polymer composition of the present invention contains a polyaniline-based conductive polymer represented by the following general formula (1) as the component (A).

(In the formula, R ^{A1 to} R ^A4 are each independently a linear, branched or cyclic monovalent hydrocarbon group having 1 to 20 carbon atoms, a hydrogen atom or a halogen atom which may have a hetero atom. R ^A1 and R ^A2 , or R ^A3 and R ^A4 may be bonded to each other to form a ring.)

The polyaniline-based conductive polymer is an organic polymer whose main chain is composed of aniline or a derivative other than the para-substituted product of aniline. Examples of the polymer having the same function include polypyrroles, polythiophenes, polyacetylenes, polyphenylenes, polyphenylene vinylenes, polyacenes, polythiophene vinylenes, and copolymers thereof.
However, high dispersibility in H ₂ O, filterability of dispersion, peelability to H ₂ O or alkali developer after film formation, low defect in lithography, ease of polymerization, low re-aggregation during storage From the viewpoint of stability in air, a polyaniline conductive polymer is selected as the component (A).

The polyaniline-based conductive polymer can obtain sufficient conductivity even if it is not substituted, but has high dispersibility in H ₂ O, low re-aggregation, filterability of the dispersion, H ₂ O after film formation Alternatively, it is more desirable to introduce a substituent for improving the peelability with respect to an alkali developer and reducing defects in lithography. A functional group such as a halogen atom, an alkyl group, a carboxy group, an alkoxy group, a hydroxy group, or a cyano group may be introduced into the substituent.

  Specific examples of the aniline monomer used to obtain the polyaniline-based conductive polymer include aniline, 2-methylaniline, 3-methylaniline, 2-ethylaniline, 3-ethylaniline, 2-isopropylaniline, 2-ter Butylaniline, 2,3-dimethylaniline, 2,5-dimethylaniline, 2,6-dimethylaniline, 3,5-dimethylaniline, 2,6-diethylaniline, 2,6-diisopropylaniline, 2,3,5 , 6-tetramethylaniline, 2-methoxyaniline, 3-methoxyaniline, 2-ethoxyaniline, 3-ethoxyaniline, 3-isopropoxyaniline, 3-hydroxyaniline, 2,5-dimethoxyaniline, 2,6-dimethoxy Aniline, 3,5-dimethoxyaniline, 2,5-diethoxya Phosphorus, 2-methoxy-5-methylaniline, 5-terbutyl-2-methoxyaniline, 2-chloro-5-methylaniline, 2-chloro-6-methylaniline, 3-chloro-2-methylaniline, 5- Examples thereof include chloro-2-methylaniline, and any one of them may be used alone, or two or more of them may be used in combination.

Among them, 2-methylaniline, 3-methylaniline, 2-ethylaniline, 3-ethylaniline, 2-isopropylaniline, 2-methoxyaniline, 3-methoxyaniline, 2-ethoxyaniline, 3-ethoxyaniline, 3-iso Dispersibility, conductivity, reactivity, product in H ₂ O when (co) polymer composed of one or two kinds selected from propoxyaniline and 3-hydroxyaniline forms a complex with polyanion It is preferably used from the viewpoint of thermal stability.

[(B) Polyanion]
The conductive polymer composition of the present invention contains a polyanion as the component (B). The polyanion used in the conductive polymer composition of the present invention is a polymer having a plurality of anion groups in one molecule, and a monomer having an anion group is polymerized, or a monomer having an anion group and an anion group It can obtain by the method of copolymerizing the monomer which does not have. These monomers can be used alone or in combination of two or more. It can also be obtained by obtaining a polymer having no anionic group and then sulfonating with a sulfonating agent such as sulfuric acid, fuming sulfuric acid, sulfamic acid and the like. Further, once a polymer having an anion group is obtained, the polyanion having a higher anion group content can be obtained by further sulfonation.

Examples of the monomer constituting the polyanion used in the present invention include a monomer containing a sulfonic acid group, a sulfonic acid group fluorinated at the α-position, a phosphoric acid group, or a carboxy group. _{^{Specifically, -O-SO 3 - H +}} , -SO 3 - H +, -CH (CF 3) -CF 2 -SO 3 - H +, -CF 2 -SO 3 - H +, -COO - _{^{H +, -O-PO 4 -}} H +, -PO 4 - monomers may be mentioned containing a strong acid group ^{H +,} and the like. Among these, from the viewpoint of doping effects on the polyaniline-based conductive _{^{polymer, -SO 3 - H +, -CH}} (CF 3) -CF 2 -SO 3 - H +, -CF 2 -SO 3 - H + , -COO ^- H ⁺ is preferred. Moreover, it is preferable that this anion group is arrange | positioned in the principal chain of a polyanion adjacently or at fixed intervals.

  Examples of the monomer containing a sulfonic acid group include styrene sulfonic acid, allyloxybenzene sulfonic acid, methallyloxybenzene sulfonic acid, vinyl sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, and 2- (methacryloxy) ethane. Sulfonic acid, 4- (methacryloxy) butanesulfonic acid, isoprenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 1,1,3,3,3-pentafluoro-2-methacryloyloxypropane-1-sulfonic acid 1,1-difluoro-2-methacryloyloxyethanesulfonic acid, 1,1,3,3,3-pentafluoro-2- (4-vinyl-benzoyloxy) -propane-1-sulfonic acid, 1,1- Difluoro-2- (4-vinyl-benzoyloxy) -ethanesulfonic acid, Jill trimethylammonium = difluorosulfoacetate 2-methacryloyloxyethyl ester, and the like. These monomers may be used alone or in combination of two or more.

  Alternatively, after polymerizing polystyrene, polymethylstyrene or the like, the polyanion used in the present invention can be obtained by sulfonation with a sulfonating agent such as sulfuric acid, fuming sulfuric acid, sulfamic acid or the like.

  Patent Documents 3 and 4 propose polymer-type sulfonium salt acid generators that generate sulfonic acid having a fluorinated α-position. The sulfonium salt of sulfonic acid bonded to the main chain of the polymer and fluorinated at the α-position is a super strong acid with very little diffusion of sulfonic acid generated by photolysis of the sulfonium salt. By doing so, the aforementioned polyanion can be obtained. When the polymer type sulfonium salt is in the form of an alkali metal salt, ammonium salt or amine salt, an inorganic or organic acid such as sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid or perchloric acid is added beforehand or positively. It is preferable to make the solution into an acid form using an ion exchange resin.

  Examples of the monomer containing a carboxy group include ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, 4-vinylbenzoic acid and crotonic acid; and ethylenically unsaturated monomers such as maleic acid, fumaric acid and itaconic acid. And saturated polyvalent carboxylic acids and acid anhydrides thereof; partially esterified products of ethylenically unsaturated polyvalent carboxylic acids such as methyl maleate and methyl itaconate; and the like. These monomers may be used alone or in combination of two or more. It is desirable to use them in combination with the sulfonic acid monomer from the viewpoint of the doping effect on the polyaniline conductive polymer.

  Examples of the monomer containing a phosphoric acid group include 3-chloro-2-acid phosphoxypropyl (meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, and mono (2-hydroxyethyl acrylate). Acid phosphate, mono (2-hydroxyethyl methacrylate) acid phosphate, mono (2-hydroxypropyl acrylate) acid phosphate, mono (2-hydroxypropyl methacrylate) acid phosphate, mono (3-hydroxypropyl acrylate) acid phosphate, mono (3 -Hydroxypropyl methacrylate) acid phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate Over doors and the like. These monomers may be used singly or in combination of two or more, and are preferably used in combination with the sulfonic acid monomer from the viewpoint of the doping effect on the polyaniline conductive polymer.

  As other monomers not containing an anion group that can be copolymerized with an anion group-containing monomer, known compounds can be used without any limitation. For example, conjugated diene monomers such as 1,3-butadiene, isoprene, 2-chloro-1,3-butadiene, 2-methyl-1,3-butadiene; styrene, α-methylstyrene, p-methylstyrene, etc. Aromatic vinyl monomers; ethylenically unsaturated carboxylic acid alkyl ester monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate; Ethylenically unsaturated carboxylic acid amide monomers such as acrylamide, methacrylamide, N, N-dimethylacrylamide, N-methylolacrylamide; ethylenically unsaturated carboxylic acids such as hydroxyalkyl (meth) acrylate and glycerin di (meth) acrylate Acid hydroxyalkyl ester monomer; vinyl carboxylate such as vinyl acetate Ester monomers; (meth) acrylonitrile, N- vinylpyrrolidone, (meth) acryloyl morpholine, cyclohexyl maleimide, isopropyl maleimide, and (meth) glycidyl acrylate.

  The said monomer can obtain the polyanion used for this invention, for example by superposing | polymerizing using an initiator.

  Further, sulfonation of polyether ketone (European Patent Application Publication No. 0041780 (A1) specification), sulfonation of polyether ether ketone (Japanese Patent Laid-Open No. 2008-108535), sulfonation of polyether sulfone (Japanese Patent Laid-Open No. Hei 10). No. 309449), polyphenylene, polyfluorene, polyvinylcarbazole sulfonated (Japanese Patent Publication No. 2010-514161), polyphenylene oxide sulfonated, polyphenylene sulfide sulfonated, and the like.

Among the polyanions, from the viewpoint of conductivity, polyisoprene sulfonic acid, a copolymer containing polyisoprene sulfonic acid, polysulfoethyl methacrylate, a copolymer containing polysulfoethyl methacrylate, poly (4-sulfobutyl methacrylate), Copolymer containing poly (4-sulfobutyl methacrylate), polymethallyloxybenzene sulfonic acid, copolymer containing polymethallyloxybenzene sulfonic acid, polystyrene sulfonic acid, copolymer containing polystyrene sulfonic acid, poly 1 , 1,3,3,3-pentafluoro-2-methacryloyloxypropane-1-sulfonic acid, poly 1,1,3,3,3-pentafluoro-2-methacryloyloxypropane-1-sulfonic acid Polymer, poly 1,1-difluoro-2-methacryloyl Copolymer containing oxyethane sulfonic acid, copolymer containing poly 1,1,3,3,3-pentafluoro-2- (4-vinyl-benzoyloxy) -propane-1-sulfonic acid, poly 1, It is preferable to use a copolymer containing 1-difluoro-2- (4-vinyl-benzoyloxy) -ethanesulfonic acid and polydifluorosulfoacetic acid 2-methacryloyloxyethyl ester.
Among them, a copolymer containing polystyrene sulfonic acid, poly 1,1,3,3,3-pentafluoro-2-methacryloyloxypropane-1-sulfonic acid, poly 1,1-difluoro-2-methacryloyloxyethane sulfonic acid, Copolymer comprising poly 1,1,3,3,3-pentafluoro-2- (4-vinyl-benzoyloxy) -propane-1-sulfonic acid, poly 1,1-difluoro-2- (4-vinyl More preferred are copolymers containing -benzoyloxy) -ethanesulfonic acid, polydifluorosulfoacetic acid 2-methacryloyloxyethyl ester, polysulfoethyl methacrylate, and poly (4-sulfobutyl methacrylate).

（式中、Ｒ^１は水素原子又はメチル基であり、Ｒ^２は単結合、エステル基、あるいはエーテル基、エステル基のいずれか又はこれらの両方を有していてもよい炭素数１〜１２の直鎖状、分岐状、環状の炭化水素基のいずれかであり、Ｚはフェニレン基、ナフチレン基、エステル基のいずれかであり、ａは０＜ａ≦１．０である。） Moreover, what is represented by following General formula (4) can also be used suitably as (B) component.

(In the formula, R ¹ is a hydrogen atom or a methyl group, and R ² has a single bond, an ester group, an ether group, an ester group, or both of which may have 1 to 12 carbon atoms. (It is any one of a linear, branched, and cyclic hydrocarbon group, Z is any one of a phenylene group, a naphthylene group, and an ester group, and a is 0 <a ≦ 1.0.)

（式中、Ｒ^１は前記と同様であり、ａ１、ａ２、ａ３、及びａ４は、それぞれ０≦ａ１≦１．０、０≦ａ２≦１．０、０≦ａ３≦１．０、０≦ａ４≦１．０、かつ０＜ａ１＋ａ２＋ａ３＋ａ４≦１．０である。） Furthermore, it is preferable that the repeating unit represented by the general formula (4) includes one or more selected from a1 to a4 represented by the following general formulas (4-1) to (4-4).

(Wherein R ¹ is as defined above, and a1, a2, a3, and a4 are 0 ≦ a1 ≦ 1.0, 0 ≦ a2 ≦ 1.0, 0 ≦ a3 ≦ 1.0, 0 ≦, respectively. a4 ≦ 1.0 and 0 <a1 + a2 + a3 + a4 ≦ 1.0.)

  The degree of polymerization of the polyanion is preferably in the range of 10 to 100,000 monomer units, and more preferably in the range of 50 to 10,000 from the viewpoint of solvent solubility and conductivity. The molecular weight of the polyanion is preferably 5,000 to 1,000,000. If it is more than the said lower limit, a polyanion will become a uniform solution easily, and if it is below the said upper limit, electroconductivity will become better.

  In the conductive polymer composition according to the present invention, the polyanion is coordinated to the polyaniline conductive polymer to form a complex of the polyaniline conductive polymer and the polyanion.

(Method for producing a composite of a polyaniline-based conductive polymer and a polyanion)
The complex of polyaniline-based conductive polymer and polyanion is prepared by, for example, adding a monomer that is a raw material of polyaniline-based conductive polymer to an aqueous solution of polyanion or a mixed solution of water and organic solvent of polyanion, and adding an oxidizing agent. It can be obtained by conducting oxidative polymerization. If the polyanion is in the form of an alkali metal salt, ammonium salt or amine salt, add an inorganic acid or organic acid such as sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, perchloric acid in advance, or use a cation exchange resin. Is preferably in acid form.

  Examples of the oxidizing agent and oxidation catalyst include peroxodisulfates such as ammonium peroxodisulfate, sodium peroxodisulfate, and potassium peroxodisulfate, transition metal compounds such as ferric chloride, ferric sulfate, and cupric chloride, silver oxide Metal oxides such as cesium oxide, peroxides such as hydrogen peroxide and ozone, organic peroxides such as benzoyl peroxide, oxygen, and the like can be used.

  As a reaction solvent used when oxidative polymerization is performed, water or a mixed solvent of water and a solvent can be used. The solvent used here is miscible with water, and is preferably a solvent that can dissolve or disperse a polyanion or polyaniline-based conductive polymer described later. For example, polar solvents such as N-methyl-2-pyrrolidone, N, N′-dimethylformamide, N, N′-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphortriamide, and alcohols such as methanol, ethanol, propanol, and butanol , Ethylene glycol, propylene glycol, dipropylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, D-glucose, D-glucitol, isoprene glycol, butanediol, 1,5-pentanediol, 1,6- Hexanediol, 1,9-nonanediol, polyvalent aliphatic alcohols such as neopentyl glycol, carbonate compounds such as ethylene carbonate and propylene carbonate, cyclic ethers such as dioxane and tetrahydrofuran Compounds, chain ethers such as dialkyl ether, ethylene glycol monoalkyl ether, ethylene glycol dialkyl ether, propylene glycol monoalkyl ether, propylene glycol dialkyl ether, polyethylene glycol dialkyl ether, polypropylene glycol dialkyl ether, 3-methyl-2- Examples include heterocyclic compounds such as oxazolidinone, and nitrile compounds such as acetonitrile, glutaronitrile, methoxyacetonitrile, propionitrile, and benzonitrile. These solvents may be used alone or as a mixture of two or more. The mixing ratio of the water-miscible solvent to water is preferably 50% by mass or less of the total reaction solvent.

The complex of the polyaniline conductive polymer and the polyanion thus obtained can be used after being finely divided by a homogenizer, a ball mill or the like, if necessary.
It is preferable to use a mixing and dispersing machine capable of applying a high shearing force for the fine graining. Examples of the mixing and dispersing machine include a homogenizer, a high-pressure homogenizer, and a bead mill. Among them, a high-pressure homogenizer is preferable.

Specific examples of the high-pressure homogenizer include a nanomizer manufactured by Yoshida Kikai Kogyo, a microfluidizer manufactured by POWREC, and an optimizer manufactured by Sugino Machine.
Examples of the dispersion process using the high-pressure homogenizer include a process in which the complex solution before the dispersion process is subjected to a high-pressure opposing collision, a process in which the complex solution is passed through an orifice or a slit at a high pressure, and the like.

  Before or after the fine granulation, impurities may be removed by a technique such as filtration, ultrafiltration, dialysis, etc., and purification may be performed with a cation exchange resin, an anion exchange resin, a chelate resin, or the like.

  The total content of the polyaniline-based conductive polymer and the polyanion in the conductive polymer composition is preferably 0.05 to 10.0% by mass. If the total content of the polyaniline-based conductive polymer and the polyanion is 0.05% by mass or more, sufficient conductivity is obtained, and if it is 5.0% by mass or less, a uniform conductive coating film is easy. Is obtained.

In addition, the complex of the polyaniline-based conductive polymer and the polyanion usually exhibits strong acidity with a pH of 1 to 2.5 unless the pH is adjusted in the H ₂ O dispersion state. In the case of coating various workpieces, the pH is preferably in the range of 4 to 8 in view of the influence of the acid on the adjacent layer. If it is in the range of pH 4 or more and pH 8 or less, corrosion by acid and acid diffusion to the adjacent layer are suppressed, and when the covering is a resist, the resist is hardly damaged, and the pattern after development becomes better. .

  The content of the polyanion is preferably such that the anion group in the polyanion is in the range of 0.1 to 10 mol, and in the range of 1 to 7 mol, per mol of the polyaniline-based conductive polymer. Is more preferable. When the anion group in the polyanion is 0.1 mol or more, the doping effect on the polyaniline-based conductive polymer is high, and sufficient conductivity can be ensured. Moreover, if the anion group in a polyanion is 10 mol or less, content of a polyaniline type conductive polymer will also become moderate, and sufficient electroconductivity will be obtained.

[(C) Betaine compound]
The conductive polymer composition of the present invention contains a betaine compound as the component (C).
In the present invention, any known betaine compound can be used.
Moreover, a betaine compound may use only 1 type and may mix and use 2 or more types.

（式中、Ｒ^Ｂ１〜Ｒ^Ｂ３はそれぞれ独立に、ヘテロ原子で置換されていてもよく、ヘテロ原子が介在してもよい炭素数１〜２０の直鎖状、分岐状又は環状の１価炭化水素基、又は水素原子を示す。また、Ｒ^Ｂ１とＲ^Ｂ２、あるいはＲ^Ｂ１とＲ^Ｂ２とＲ^Ｂ３は互いに結合して式中のＡ^＋と共に環を形成してもよい。Ａ^＋はヘテロ原子であり、一価の陽イオンを示す。ｋは１〜８の整数を示す。Ｌは炭素原子又はヘテロ原子であり、ｋが２以上の場合、これらの両方を有していてもよい。Ｒ^Ｂ４、Ｒ^Ｂ５は水素原子、又はヘテロ原子が介在してもよい炭素数１〜２０の直鎖状、分岐状又は環状の１価炭化水素基を示す。また、Ｒ^Ｂ４とＲ^Ｂ５は互いに結合して環を形成してもよい。Ｂ⁻は一価のアニオン性官能基であり、カルボン酸イオン又はスルホン酸イオンを示す。） As a betaine compound used for this invention, what is represented by following General formula (2) is preferable.

(In the formula, R ^{B1 to} R ^B3 are each independently substituted with a heteroatom, and a linear, branched or cyclic monovalent carbon atom having 1 to 20 carbon atoms in which the heteroatom may be interposed. Represents a hydrogen group or a hydrogen atom, and R ^B1 and R ^B2 , or R ^B1 , R ^B2 and R ^B3 may combine with each other to form a ring together with A ⁺ in the formula, where A ⁺ is a heteroatom. And represents a monovalent cation, k represents an integer of 1 to 8. L is a carbon atom or a hetero atom, and when k is 2 or more, it may have both of them. ^B4 and R ^{B5 each} represent a hydrogen atom or a linear, branched or cyclic monovalent hydrocarbon group having 1 to 20 carbon atoms that may be intervened by a hetero atom, and R ^B4 and R ^B5 are bonded to each other. may form a ring by .B ^- is an anionic functional group monovalent carboxylic acid It indicates on or sulfonic acid ion.)

In the general formula (2), A ⁺ is a heteroatom and represents a monovalent cation. Examples of A ⁺ include sulfonium ions and ammonium ions.
B ⁻ is a monovalent anionic functional group and represents a carboxylate ion or a sulfonate ion. B ⁻ forms an inner salt with A ⁺ existing in the same molecule, or forms a salt with A ⁺ of an adjacent molecule between two molecules.

（式中、Ｒ^Ｂ１〜Ｒ^Ｂ５、Ａ^＋、Ｌ、及びｋは、前記と同様である。） Moreover, as (C) component, what is represented by following General formula (3) is more preferable.

(In the formula, R ^{B1 to} R ^B5 , A ⁺ , L, and k are the same as described above.)

Specific examples of the structure of the betaine compound represented by the general formula (2) having a sulfonate ion include the following.

  Specific examples of the structure of the betaine compound represented by the general formula (3) include the following.

  Further, the content of the betaine compound is preferably 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the complex of the polyaniline conductive polymer and the polyanion, and further 3 parts by mass to 10 parts by mass. Part is preferred. If the content of the betaine compound is such, acid diffusion from the antistatic film formed by the conductive polymer composition of the present invention to the resist layer is reduced, and the antistatic effect at the time of electron beam drawing is reduced. While being held, the influence of lithography on the lithography is reduced, and a high-resolution resist pattern can be obtained. Further, from the same effect, it is possible to obtain a resist workpiece with little sensitivity variation over time from film formation to pattern development.

(Surfactant)
In the present invention, a surfactant may be added in order to improve wettability to a workpiece such as a substrate. A preferable surfactant is a nonionic surfactant. Specific examples include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene carboxylic acid ester, sorbitan ester, polyoxyethylene sorbitan ester, and acetylene glycol.

  The content of the nonionic surfactant is preferably 1 part by mass to 50 parts by mass, and more preferably 2 parts by mass to 20 parts by mass with respect to 100 parts by mass of the complex of the polyaniline conductive polymer and the polyanion. . If it is not less than the above lower limit, the wettability to the resist surface will be better, and if it is not more than the above upper limit, the antistatic ability will be sufficient.

  In order to obtain the conductive polymer composition of the present invention, for example, a complex of a polyaniline-based conductive polymer and a polyanion, a solvent, a surfactant, and the like are mixed, and a betaine compound is further added. It can be obtained by applying a high-pressure homogenizer or the like and further filtering by a UPE filter.

  The conductive polymer composition thus obtained can be applied to a workpiece such as a base material to form an antistatic film. Examples of the method for applying the conductive polymer composition include application using a bar coater, spin coating, dipping, comma coating, spray coating, roll coating, gravure printing, and the like. After application, an antistatic film is formed by heat treatment using a hot air circulating furnace, a hot plate, or the like.

  Examples of the workpiece include a glass substrate, a quartz substrate, a photomask blank substrate, a resin substrate, a compound semiconductor wafer such as a silicon wafer, a gallium arsenide wafer, and an indium phosphide wafer.

  Examples of the coated article coated with the antistatic film obtained using the conductive polymer composition of the present invention include, for example, a glass substrate provided with an antistatic film, a resin film provided with an antistatic film, and an antistatic film. Examples thereof include a resist substrate provided with a film.

  In particular, since the conductive polymer composition of the present invention does not adversely affect the resist, it can be suitably used as long as the workpiece is a substrate provided with a chemically amplified resist film. In the case of a substrate for obtaining a resist pattern by pattern irradiation with an electron beam, a more preferable result can be obtained.

  The present invention also includes a step of forming an antistatic film using the conductive polymer composition of the present invention on the resist film of a substrate provided with a chemically amplified resist film, a step of pattern irradiation with an electron beam, and Provided is a pattern forming method including a step of developing with an alkaline developer to obtain a resist pattern.

  The pattern forming method can be performed according to a conventional method except that the conductive polymer composition of the present invention is used, and may be developed after a post-exposure heat treatment, an etching step, a resist removal step, Of course, various other processes such as a cleaning process may be performed.

  According to such a pattern forming method, a charging phenomenon at the time of exposure can be prevented, and a resist pattern having high sensitivity, high resolution, and good pattern shape can be obtained.

  The present invention also provides a substrate having a resist pattern obtained by the pattern forming method.

  Although the present invention is designed for use in lithography using an electron beam or the like, it is suitable for use in antistatic applications such as lithography, film, and glass using ultraviolet rays because of its excellent antistatic ability. Can do.

EXAMPLES Hereinafter, although a manufacture example, an Example, and a comparative example are given and this invention is shown more concretely, this invention is not limited by these Examples.
In addition, the measuring method and evaluation method of each physical property are as follows.

  A spin coater MS-A200 (manufactured by Mikasa Co., Ltd.) was used for producing the antistatic film in Examples 1 to 10 and Comparative Examples 1 to 4 and the resist film used as the lower layer by spin coating. The positive chemically amplified resist used was a positive chemically amplified electron beam resist (a) manufactured by Shin-Etsu Chemical. Moreover, Shin-Etsu Chemical Co., Ltd. (b) was used for the negative type chemically amplified electron beam resist.

  The positive chemical amplification resist (a) and the negative chemical amplification resist (b) were formed by baking at 110 ° C. for 240 seconds with a precision incubator and removing the solvent. The antistatic films of Examples 1 to 4 were formed by baking at 90 ° C. for 90 seconds with a precision thermostat and removing the solvent. The resist film thickness and antistatic film thickness were determined with a spectroscopic ellipsometer VASE (manufactured by JA Woollam Co., Ltd.) having a variable incident angle.

(Filterability)
After preparing the conductive polymer compositions of the following examples and comparative examples, filtration is performed using a UPE filter (manufactured by Entegris) having a pore size of 0.5 to 0.050 μm, and the filter is filtered without causing clogging. The pore size of the possible filter was examined. In Examples 1 to 10 and Comparative Examples 1 to 4 below, the permeation limit of the UPE filter on which the conductive polymer composition was filtered is shown in Table 1.

(PH measurement)
The pH of the conductive polymer compositions of Examples 1 to 10 and Comparative Examples 1 to 4 was measured using a pH meter D-52 (manufactured by Horiba, Ltd.). The results are shown in Table 1.

(Film formability)
Evaluation was performed based on the criteria that a film that was able to form a uniform film was ◯, and the refractive index was measured, but a defect that originated from particles or a portion that was partially striationd on the film was evaluated as x. The evaluation results are shown in Table 1.

(Washing peelability)
10 μL of the conductive polymer composition is dropped onto the resist (a) or resist (b) film obtained by the film formation method, heated at 90 ° C. for 90 seconds with a precision incubator, and then at room temperature in air. Left under for 2 minutes. The formed antistatic film was washed away with ion exchange water contained in a washing bottle. Evaluation was made based on the criteria that the antistatic film was peeled off within 10 seconds, the case where it was peeled off within 10 seconds for more than 10 seconds, and the reason for others that could not be evaluated. The evaluation results are shown in Table 1.

(Resist damage)
In the substrate after the water washing peelability evaluation, the substrate where the antistatic film has been peeled off has no change in color on the base resist portion, the portion in which the color change is seen on some is Δ, and the overall color change Evaluation was performed based on the criteria of x being observed. The evaluation results are shown in Table 1.

(Surface resistivity)
The surface resistivity (Ω / □) of the antistatic film was measured using a Hiresta-UP MCP-HT450 and a genuine J box U type probe MCP-JB03 (manufactured by Mitsubishi Chemical Corporation). The results are shown in Table 1.

(Electron beam lithography evaluation and PCD (Post Coating Delay) evaluation)
The time-dependent change by the influence from the conductive polymer film of the resist film before irradiation was measured. The two-layer film of resist film and conductive polymer film coated by the method described below is allowed to stand for 7 days, 14 days, and 30 days immediately after film formation in an electron beam lithography apparatus, and the following conductivity is obtained: A resist pattern was obtained by a pre-PEB peeling process or a post-PEB peeling process of the polymer film. With respect to the sensitivity when the resist and the conductive polymer film were drawn immediately after the film formation, the variation of the pattern line width at the same sensitivity was obtained.

-PEB pre-peeling process evaluation (a) which is a positive chemically amplified resist is spin-coated onto a 6-inch silicon wafer using MARK VIII (manufactured by Tokyo Electron Co., Ltd., coater developer clean track) on a hot plate A 150 nm resist film was prepared by pre-baking at 110 ° C. for 240 seconds. The conductive polymer composition was spin-coated using MARK VIII on the obtained resist-coated wafer as described above, and baked on a hot plate at 90 ° C. for 90 seconds to prepare a conductive polymer film. A resist pattern was obtained by the following method immediately after coating, 7 days, 14 days, and 30 days after coating the wafer on which the two-layer film of the resist film and the conductive polymer film was coated. First, the wafer immediately after coating is exposed using an electron beam exposure apparatus (manufactured by Hitachi High-Technologies Corporation, HL-800D acceleration voltage 50 keV), and then a pure polymer is applied for 15 seconds to form a conductive polymer film. After peeling, the substrate was baked at 110 ° C. for 240 seconds (PEB: post exposure bake), and developed with an aqueous solution of 2.38% by mass of tetramethylammonium hydroxide. The produced wafer with a pattern was observed with a sky SEM (scanning electron microscope), and the exposure amount for resolving 400 nm line and space at 1: 1 was defined as the optimum exposure amount (sensitivity) (μC / cm ² ). The minimum dimension at the optimum exposure dose was taken as the resolution. Also, a resist pattern is obtained in the same manner for wafers that have passed 7 days, 14 days, and 30 days after coating, and the exposure amount that resolves the 400 nm line and space in 1: 1 on the wafer immediately after coating is optimally exposed. Variation in pattern line width in quantity (sensitivity) (μC / cm ² ) was measured. The results are shown in Table 2.

-Evaluation of post-PEB release process A wafer coated with a bilayer film of a resist film and a conductive polymer film was prepared in the same manner as in the pre-PEB exfoliation process. Each was subjected to a post exposure bake (PEB) for 240 seconds at 110 ° C. without passing through a step of peeling the conductive polymer film by pouring pure water for 15 seconds after the electron beam exposure, and 2.38% by mass. A resist pattern was obtained by developing with an aqueous solution of tetramethylammonium hydroxide. The variation of the pattern line width at the optimum exposure dose (sensitivity) (μC / cm ² ) was measured as the exposure dose for resolving the 400 nm line and space at 1: 1 on the wafer immediately after coating. The results are shown in Table 3.

  For the negative resist (b), the same evaluation as the positive resist (a) was performed for the pre-PEB stripping process and the post-PEB stripping process. The results are shown in Tables 4 and 5.

The monomer used for the manufacture example below is shown.

(Production Example 1) Synthesis of dopant polymer 1 1.14 g of ammonium persulfate oxidized in advance by dissolving 206 g of sodium salt of monomer 1 in 1,000 ml of ion-exchanged water and stirring at 80 ° C. in advance in 10 ml of water The agent solution was added dropwise for 20 minutes, and the solution was stirred for 2 hours.
1,000 ml of sulfuric acid diluted to 10% by mass and 10,000 ml of ion-exchanged water were added to the sodium polystyrenesulfonate-containing solution thus obtained, and the polystyrenesulfonic acid-containing solution was added using an ultrafiltration method. About 10,000 ml of solution was removed, 10,000 ml of ion-exchanged water was added to the remaining solution, and about 10,000 ml of solution was removed using an ultrafiltration method. The above ultrafiltration operation was repeated three times.
Further, about 10,000 ml of ion-exchanged water was added to the obtained filtrate, and about 10,000 ml of solution was removed using an ultrafiltration method. This ultrafiltration operation was repeated three times.
Water in the obtained solution was removed under reduced pressure to obtain colorless solid polystyrene sulfonic acid.

The ultrafiltration conditions were as follows (the same applies to other examples).
-Molecular weight cut off of ultrafiltration membrane: 30K
・ Cross flow type ・ Supply liquid flow rate: 3,000 ml / min ・ Membrane partial pressure: 0.12 Pa
This polymer compound is referred to as (dopant polymer 1).

Production Example 2 Synthesis of Dopant Polymer 2 To 37.5 g of methanol stirred at 64 ° C. in a nitrogen atmosphere, 37.5 g of monomer 2, 12.5 g of lithium salt of monomer 1, and 2,2′-azobis (isobutyric acid) ) A solution prepared by dissolving 3.04 g of dimethyl in 112.5 g of methanol was added dropwise over 4 hours. The mixture was further stirred at 64 ° C. for 4 hours. After cooling to room temperature, it was added dropwise to 1,000 g of ethyl acetate with vigorous stirring. The resulting solid was filtered off and vacuum dried at 50 ° C. for 15 hours to obtain 47.1 g of a white polymer.
The obtained white polymer was dissolved in 424 g of methanol, and the lithium salt was converted into a sulfo group using an ion exchange resin. When the obtained polymer was measured by ¹⁹ F, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymerization composition ratio (molar ratio) Monomer 1: Monomer 2 = 1: 1
Weight average molecular weight (Mw) = 39,000
Molecular weight distribution (Mw / Mn) = 1.81
This polymer compound is referred to as (dopant polymer 2).

(Production Example 3) Synthesis of polyaniline-based conductive polymer composite using dopant polymer 1 27.5 g of 2-methoxyaniline and 41.1 g of dopant polymer 1 obtained in Production Example 1 were added in excess of 1,000 mL. The solution dissolved in pure water was mixed at 25 ° C.
While maintaining the mixed solution thus obtained at 0 ° C. and stirring, 45.9 g of ammonium persulfate dissolved in 200 mL of ultrapure water was slowly added, and the mixture was stirred and reacted.
The obtained reaction solution was concentrated and then added dropwise to 4,000 mL of acetone to obtain a green powder. This green powder was again dispersed in 1,000 mL of ultrapure water and dropped into 4,000 mL of acetone to purify and recrystallize the green powder. This operation was repeated three times, and the obtained green powder was redispersed in 2,000 mL of ultrapure water, and about 1,000 mL of water was removed using an ultrafiltration method. This operation was repeated 10 times and again dropped into 4,000 mL of acetone to obtain a conductive polymer composite green powder.
This conductive polymer composite is referred to as (polyaniline composite 1).

(Production Example 4) Synthesis of polyaniline-based conductive polymer composite using dopant polymer 2 27.5 g of 2-methoxyaniline and 61.1 g of dopant polymer 2 obtained in Production Example 2 were added in excess of 1,000 mL. The solution dissolved in pure water was mixed at 25 ° C.
While maintaining the mixed solution thus obtained at 0 ° C. and stirring, 45.8 g of ammonium persulfate dissolved in 200 mL of ultrapure water was slowly added, and the mixture was stirred and reacted.
The obtained reaction solution was concentrated and then added dropwise to 4,000 mL of acetone to obtain a green powder. This green powder was again dispersed in 1,000 mL of ultrapure water and dropped into 4,000 mL of acetone to purify and recrystallize the green powder. This operation was repeated three times, and the obtained green powder was redispersed in 2,000 mL of ultrapure water, and about 1,000 mL of water was removed using an ultrafiltration method. This operation was repeated 10 times and again dropped into 4,000 mL of acetone to obtain a conductive polymer composite green powder.
This conductive polymer composite is referred to as (polyaniline composite 2).

Example 1
11.5 g of polyaniline complex 1 obtained in Production Example 3, 354 g of ion-exchanged water, 0.08% by mass of β-Alanine (manufactured by Tokyo Chemical Industry), and 0.05% by mass of SURFINOL 465 (manufactured by Nissin Chemical Industry) ) And then filtered using a UPE filter subjected to a hydrophilic treatment to prepare a conductive polymer composition.

(Example 2)
A conductive polymer composition was prepared in the same manner as in Example 1 except that β-Aline (manufactured by Tokyo Chemical Industry Co., Ltd.) used in Example 1 was changed to 0.04% by mass.

(Example 3)
The conductive polymer composition was prepared in the same manner as in Example 1, except that 0.08% by mass β-Aline used in Example 1 was changed to 0.15% by mass L-Carnitine (manufactured by Tokyo Chemical Industry Co., Ltd.).

Example 4
A conductive polymer composition was prepared in the same manner except that L-Carnitine (manufactured by Tokyo Chemical Industry Co., Ltd.) used in Example 3 was changed to 0.08% by mass.

(Example 5)
11.5 g of the polyaniline complex 2 obtained in Production Example 4, 354 g of ion-exchanged water, 0.08% by mass of β-Alanine (manufactured by Tokyo Chemical Industry), and 0.05% by mass of SURFINOL 465 (manufactured by Nissin Chemical Industry) ) And then filtered using a UPE filter subjected to a hydrophilic treatment to prepare a conductive polymer composition.

(Example 6)
A conductive polymer composition was prepared in the same manner as in Example 5, except that β-Aline (manufactured by Tokyo Chemical Industry Co., Ltd.) used in Example 5 was changed to 0.04% by mass.

(Example 7)
Conductivity was the same as in Example 5, except that 0.08% by mass of β-Alane (produced by Tokyo Chemical Industry) used in Example 5 was changed to 0.15% by mass of L-Carnitine (produced by Tokyo Chemical Industry). A functional polymer composition was prepared.

(Example 8)
Conductivity was the same as in Example 5, except that 0.08% by mass of β-Alinene (manufactured by Tokyo Chemical Industry) used in Example 5 was changed to 0.08% by mass of L-Carnitine (manufactured by Tokyo Chemical Industry). A functional polymer composition was prepared.

Example 9
Example 5 0.08% by weight of β-Alanine was used (manufactured by Tokyo Chemical Industry Co., Ltd.) of 0.18 mass% Dimethylethylammoniumpropanesulf o nate (produced by Wako Pure Chemical Industries, Ltd. Product name: NDSB-195) the other was changed to, the implementation A conductive polymer composition was prepared in the same manner as in Example 5.

(Example 10)
Example 5 0.08% by weight of β-Alanine was used (manufactured by Tokyo Chemical Industry Co., Ltd.) of 0.24 mass% Dimethylbenzylammoniumpropanesulf o nate (produced by Wako Pure Chemical Industries, Ltd. Product name: NDSB-256) the other was changed to, the implementation A conductive polymer composition was prepared in the same manner as in Example 5.

(Comparative Example 1)
In contrast to Example 1, a conductive polymer composition was prepared in the same manner as Example 1 except that no betaine compound was used.

(Comparative Example 2)
A conductive polymer composition was prepared in the same manner as in Example 5, except that no betaine compound was used.

(Comparative Example 3)
The betaine compound used in Examples 1 to 4 was changed to ammonia water (28% manufactured by Kanto Chemical Co., Inc.), and a conductive polymer composition was prepared using the pH and surface resistivity fluctuations of the conductive polymer composition as indices. . The amount of ammonia water added was 0.11% by mass.

(Comparative Example 4)
The betaine compound used in Examples 5 to 10 was changed to ammonia water (28% manufactured by Kanto Chemical Co., Inc.), and a conductive polymer composition was prepared using the pH and surface resistivity fluctuations of the conductive polymer composition as indicators. . The amount of ammonia water added was 0.12% by mass.

  Tables 1 to 5 show the filtration filter pore size, film formability, water detachability, resist damage, pH, surface resistance, and electrons of the antistatic film obtained from the conductive polymer compositions prepared in Examples and Comparative Examples. Lithography evaluation in a line drawing machine is shown.

As shown in Table 1, Examples 1 to 10, which are the conductive polymer compositions of the present invention, have a pH as a relaxation index of acidity with respect to Comparative Examples 1 and 2, which are compositions to which no betaine compound was added. As compared with Comparative Examples 3 and 4, it was possible to obtain a composition that suppresses the influence of the acid on the resist film without increasing the surface resistivity of the film or impairing the film quality.
On the other hand, Comparative Examples 1 and 2, which are compositions without the addition of a betaine compound, have an excellent antistatic effect, but the pH is low, and the acid in the composition easily diffuses into the resist, adversely affecting the resist pattern. .
In Comparative Examples 3 and 4, although the pH improvement was originally expected, a phenomenon that the conductive polymer composition was denatured was confirmed, discoloration or precipitation occurred, and the surface resistivity also increased. Therefore, it did not function as a composition coated on the resist as an antistatic film for the electron beam resist.

  Moreover, as shown in Tables 2-5, also in the lithography evaluation using an electron beam, those using the antistatic film obtained from the conductive polymer composition of the present invention (Examples 1 to 10) were compared. With respect to Examples 1 and 2, the sensitivity change with time was controlled, and the resolution and pattern shape were also improved. Regarding the PCD evaluation, the higher the pH, the better, and the storage stability of the resist and the coating of the conductive polymer film (antistatic film) can be easily adjusted while considering the surface resistivity value. On the other hand, Comparative Examples 1 and 2, which are compositions not containing a betaine compound, have an excellent antistatic effect as described above, but have a low pH and a very large fluctuation range for PCD. There was a problem in the storage stability of the coating of the polymer membrane. In addition, in Comparative Examples 3 and 4, when the added aqueous ammonia was added in an amount effective for pH control, the conductive polymer was partially dedoped and the surface resistivity was increased. The function has deteriorated.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

Claims (13)

A polyaniline-based conductive polymer (A) having a repeating unit represented by the following general formula (1), a polyanion (B), and a betaine compound (C) ,
The said (B) component contains what is represented by following General formula (4), The conductive polymer composition characterized by the above-mentioned .

(Wherein R ^{A1 to} R ^A4 each independently have a hetero atom, a C 1-20 linear, a C 3-20 branched or cyclic monovalent hydrocarbon group, hydrogen R represents either an atom or a halogen atom, and R ^A1 and R ^A2 , or R ^A3 and R ^A4 may combine with each other to form a ring.

(In the formula, R ¹ is a hydrogen atom or a methyl group, and R ² has a single bond, an ester group, an ether group, an ester group, or both of which may have 1 to 12 carbon atoms. It is a linear or branched or cyclic hydrocarbon group having 3 to 12 carbon atoms, Z is any one of a phenylene group, a naphthylene group, and an ester group, and a is 0 <a ≦ 1.0. .) The conductive polymer composition according to claim 1, wherein the component (C) is represented by the following general formula (2).

(In the formula, R ^{B1 to} R ^B3 are each independently substituted with a heteroatom and may be a straight chain having 1 to 20 carbon atoms or a branched chain having 3 to 20 carbon atoms that may be interspersed with a heteroatom. Or a monovalent hydrocarbon group or a hydrogen atom, or R ^B1 and R ^B2 , or R ^B1 , R ^B2 and R ^B3 may be bonded to each other to form a ring together with A ⁺ in the formula A ⁺ is a heteroatom and represents a monovalent cation, k represents an integer of 1 to 8. L is a carbon atom or a heteroatom, and when k is 2 or more, both of them are present. R ^B4 and R ^B5 are each a hydrogen atom, a straight chain of 1 to 20 carbon atoms , or a branched or cyclic monovalent hydrocarbon having 3 to 20 carbon atoms, in which a hetero atom may be interposed. . a group ^{addition, R B4} and ^{R B5} mAY bonded to each other to form a ring .B ^- is The valence of the anionic functional group, a carboxylic acid ion or sulfonic acid ion.) The conductive polymer composition according to claim 2, wherein the component (C) is represented by the following general formula (3).

(In the formula, R ^{B1 to} R ^B5 , A ⁺ , L, and k are the same as described above.) The content of the component (C) is 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the composite of the component (A) and the component (B). Item 4. The conductive polymer composition according to any one of Items 3 . The content of component (C), according to claim 4, characterized in that the component (A) and the (B) 10 parts by mass 3 parts by mass with respect to the complex of 100 parts by mass of the component Conductive polymer composition. The conductive polymer composition according to any one of claims 1 to 5 , wherein the conductive polymer composition further contains a nonionic surfactant. Claim 6 wherein the content of the nonionic surfactant, the relative complex of 100 parts by mass of the (A) component and the (B) component is from 1 part by weight, characterized in that 50 parts by weight The conductive polymer composition described in 1. The conductive polymer composition according to any one of claims 1 to 7 , wherein the conductive polymer composition is used for forming an antistatic film. A coated article comprising an antistatic film formed using the conductive polymer composition according to any one of claims 1 to 8 on a workpiece. The coated article according to claim 9 , wherein the workpiece is a substrate including a chemically amplified resist film. The coated article according to claim 10 , wherein the workpiece is a substrate for obtaining a resist pattern by pattern irradiation with an electron beam. A step of forming an antistatic film on the resist film of a substrate comprising a chemically amplified resist film using the conductive polymer composition according to any one of claims 1 to 8 , an electron beam A pattern forming method comprising: a step of pattern irradiation; and a step of developing using an alkaline developer to obtain a resist pattern. A substrate having a resist pattern obtained by the pattern forming method according to claim 12 .