KR20120134046A - Polymer, chemically amplified resist composition, and patterning process using said chemically amplified resist composition - Google Patents

Abstract

PURPOSE: A polymer compound is provided to form a pattern with excellent resolution and excellent rectangular ability and to obtain a resist material with good adhesion as a substrate. CONSTITUTION: A polymer compound contains a repeating unit in chemical formula 1. In chemical formula 1, R^1 is a hydrogen, fluorine, methyl, or trifluoromethyl, R^2, R^3 and R^4 is selected from a substituted or unsubstituted C1-10 linear, branched or cyclic alkyl, alkenyl and oxoalkyl or can form a ring with a sulfur atom combined with two or more of R^2, R^3 and R^4, X^1 is O or CH2, A^1 is a C1-10 linear, branched or cyclic divalent hydrocarbon group, B^1 is C1-10 alkylene or C6-18 arylene which can comprise hetero atoms except fluorine, and k^1 is 0 or 1.

Description

Polymer compound, chemically amplified resist material, pattern formation method using this chemically amplified resist material {POLYMER, CHEMICALLY AMPLIFIED RESIST COMPOSITION, AND PATTERNING PROCESS USING SAID CHEMICALLY AMPLIFIED RESIST COMPOSITION}

The present invention relates to (1) a polymer compound, (2) a chemically amplified resist material containing this polymer compound, and (3) a pattern formation method using this chemically amplified resist material. In the present invention, the high energy ray includes ultraviolet rays, far ultraviolet rays, electron beams, EUV, X-rays, excimer lasers, gamma rays, and synchrotron radiation.

In recent years, finer pattern rule has been demanded due to higher integration and higher speed of LSI, and far ultraviolet lithography and vacuum ultraviolet lithography are promising as the next generation fine processing technology. Among them, photolithography using ArF excimer laser light as a light source is an indispensable technique for ultrafine processing of 0.13 µm or less.

ArF lithography began to be used in part from device fabrication of 130 nm nodes, becoming a major lithography technique from 90 nm node devices. As a lithography technique for the next 45 nm node, 157 nm lithography using the F ₂ laser was initially promising, but development delays due to various problems have been pointed out, so that air such as water, ethylene glycol, glycerin, etc. between the projection lens and the wafer has been pointed out. By inserting a liquid with a higher refractive index, the numerical aperture (NA) of the projection lens can be designed to 1.0 or more, and ArF immersion lithography capable of achieving a high resolution suddenly emerges (for example, see Non-Patent Document 1). It is in the practical stage. For this immersion lithography, a resist material which is hard to elute in water is required.

In ArF lithography, in order to prevent deterioration of an accurate and expensive optical material, a highly sensitive resist material capable of exhibiting sufficient resolution with a small exposure amount is required. As a measure to realize, each component thereof has a wavelength of 193 nm. It is most common to choose something that is highly transparent. For example, with respect to the base resin, polyacrylic acid and its derivatives, norbornene-maleic anhydride alternating polymers, polynorbornene and ring-opening metathesis polymers, ring-opening metathesis polymers, hydrogenated additives, and the like have been proposed. In terms of performance, some results were obtained.

In addition, various studies have been made on photoacid generators and additives to achieve high resolution. For example, in order to control the diffusion of the acid generated by exposure, it is generally known that high resolution is obtained by adding a basic compound such as an amine as a quencher. In addition, two or more kinds of photoacid generators may be mixed and used, and when one photoacid generator is an onium salt that generates a so-called weak acid, it may be possible to have a function of acid diffusion control (Patent Document 1, Patent Document 2). That is, when an onium salt that generates a strong acid such as a fluorine-substituted sulfonic acid and an onium salt that generates a weak acid such as a fluorine-free sulfonic acid or a carboxylic acid are used in combination with a photoacid generator by high energy ray irradiation. When the generated strong acid collides with the onium salt having an unreacted weak acid anion, the weak acid is released by salt exchange to generate an onium salt having a strong acid anion. In this process, the strong acid is exchanged with a weaker acid having a lower catalytic ability, so that the acid is deactivated in appearance and the acid diffusion can be controlled. Where the photoacid generator that generates the strong acid is an onium salt, the strong acid generated by the high energy ray irradiation may be replaced with a weak acid, but the weak acid generated by the high energy ray irradiation collides with the onium salt that generates the unreacted strong acid. Salt exchange is not possible. These are due to the phenomenon that onium cations are more likely to form ion pairs with anions of strong acids. However, since the onium salt itself, which generates a weak acid, has mobility and diffusivity in the resist material, a problem remains in that high resolution is achieved, such as an effect on lithography characteristics and elution into an immersion liquid.

Moreover, the onium salt of the resin bond type which the anion of weak acid couple | bonded in resin is developed (patent document 3, patent document 4). As a result, it is possible to control the movement and diffusion of the weak acid onium salt, but there is still a problem in overcoming defects such as peeling from the substrate of the resist pattern, which is often observed in the resist to which the weak acid anion is added.

Japanese Patent Laid-Open No. 2010-155824 Japanese Patent Publication No. 2008-158339 WO 2010119910 Japanese Patent Laid-Open No. 2011-37834

 Journal of photopolymer Science and Technology Vol. 17, No. 4, p 587 (2004)

This invention is made | formed in view of the said situation, and in photolithography which used the high energy ray, such as ArF excimer laser beam and EUV, as a light source, it is possible to form the pattern which is excellent in the resolution and especially the pattern-shaped rectangularity. An object of the present invention is to provide a polymer compound capable of obtaining a resist material having appropriate adhesion to a substrate, a chemically amplified resist material containing the polymer compound, and a pattern forming method using the chemically amplified resist material.

According to the present invention to solve the above problems, there is provided a polymer compound containing a repeating unit represented by the following formula (1).

(Wherein R ¹ represents any ^one of a hydrogen atom, a fluorine atom, a methyl group and a trifluoromethyl group, and R ² , R ³ and R ⁴ each independently represent a substituted or unsubstituted straight chain having 1 to 10 carbon atoms, Any of branched or cyclic alkyl, alkenyl and oxoalkyl groups, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, an aralkyl group and an aryloxoalkyl group, or R ² , R ³ and Any two or more of R ⁴ may be bonded to each other to form a ring together with a sulfur atom in the formula, X ¹ represents O or CH ₂ , and A ¹ is linear, branched or cyclic having 1 to 10 carbon atoms. Represents a divalent hydrocarbon group, B ¹ represents an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 18 carbon atoms, which may include a hetero atom other than fluorine, and k ¹ represents an integer of 0 or 1)

The repeating unit represented by the formula (1) has a sulfonium salt structure of sulfonic acid in which B ¹ is not fluorine-substituted, and has a lactone structure. Therefore, when the polymer compound having such a repeating unit is used as the base resin of the chemically amplified resist material, it is possible to appropriately control the movement and diffusion of the strong acid generated from the acid generator, and the resulting resist pattern has excellent rectangularity. The adhesiveness to the board | substrate of a pattern is also favorable. Furthermore, since the elution of the anion component of a sulfonium salt is low, it can use especially suitably as an immersion lithography material.

Moreover, it is preferable that the said high molecular compound contains the repeating unit which has an acid labile group in addition to the repeating unit represented by the said General formula (1).

The repeating unit represented by the formula (1) included in the polymer compound of the present invention may function not only as an acid migration and diffusion control function by selecting an acid labile unit, but also as a unit that generates acid itself. .

Moreover, this invention provides the chemically amplified resist material characterized by containing (A) the said high molecular compound, (B) organic solvent, (C) photoacid generator, and (D) basic compound.

Thus, when the chemically amplified resist material containing the high molecular compound of this invention is used, the resist pattern excellent in rectangularity and favorable adhesiveness to a board | substrate can be obtained.

In addition, the present invention includes a step of applying the chemically amplified resist material on a substrate, a step of exposing with a high energy ray through a photomask after heat treatment, and a step of developing using a developer. It provides a pattern formation method.

In the present invention, a step of applying the chemically amplified resist material on a substrate, a step of applying a protective film insoluble in water and soluble in an alkaline developer after heat treatment, and inserting water between the substrate and the projection lens It provides a pattern forming method comprising the step of exposing to a high energy ray through a photomask, and the step of developing using a developer.

Thus, the resist pattern which is excellent in rectangularity and favorable adhesiveness to a board | substrate can be obtained by the pattern formation method of this invention. Moreover, since the elution of the anion component of a sulfonium salt is low, it can use suitably for immersion lithography materials.

The chemically amplified resist material using a high molecular compound containing a sulfonium salt containing a sulfonate anion and a sulfonium cation having a specific structure of the present invention as a base resin is excellent in resolution, in particular in a pattern-shaped rectangularity. Moreover, since it has a lactone structure in a repeating unit, it has the outstanding adhesiveness to the board | substrate of resin, is strong in pattern collapse, and is very useful.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to achieve the said objective, the resist material which used the resin composition which has a repeating unit of the sulfonic acid anion of the specific structure represented by following General formula (1) as a resist base resin is the resolution of a resist, especially a pattern The present invention has been completed by finding that the rectangular shape of the shape is excellent, the adhesion to the substrate is excellent, the peeling of the line and space pattern, etc. is small, and it is very effective for precise microfabrication as a resist material.

EMBODIMENT OF THE INVENTION Hereinafter, the high molecular compound, the chemically amplified resist material, and the pattern formation method of this invention are demonstrated. First, the high molecular compound provided by this invention contains the repeating unit represented by following formula (1).

≪ Formula 1 >

(Wherein R ¹ represents any ^one of a hydrogen atom, a fluorine atom, a methyl group and a trifluoromethyl group, and R ² , R ³ and R ⁴ each independently represent a substituted or unsubstituted straight chain having 1 to 10 carbon atoms, Any of branched or cyclic alkyl, alkenyl and oxoalkyl groups, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, an aralkyl group and an aryloxoalkyl group, or R ² , R ³ and Any two or more of R ⁴ may be bonded to each other to form a ring together with a sulfur atom in the formula, X ¹ represents O or CH ₂ , and A ¹ is linear, branched or cyclic having 1 to 10 carbon atoms. Represents a divalent hydrocarbon group, B ¹ represents an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 18 carbon atoms, which may include a hetero atom other than fluorine, and k ¹ represents an integer of 0 or 1)

Although the following may specifically be illustrated as a C1-C10 alkylene group or a C6-C18 arylene group which may contain the hetero atom except the fluorine represented by B <^1> in the said General formula (1), It is not limited. In addition, in this invention, the hetero atom except fluorine means nitrogen, oxygen, a sulfur atom, etc.

(Indicated by broken line in formula)

In Formula 1, any one of a substituted or unsubstituted linear, branched or cyclic alkyl group, alkenyl group and oxoalkyl group represented by R ² , R ³ and R ⁴ , or substituted or unsubstituted Specifically, as the aryl group, aralkyl group and aryl oxoalkyl group having 6 to 18 carbon atoms, as the substituted or unsubstituted alkyl group, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert- Butyl group, pentyl group, hexyl group, heptyl group, octyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclopropylmethyl group, 4-methylcyclohexyl group, cyclohexylmethyl group, norbornyl group, adamantyl group, etc. Can be mentioned.

Examples of the substituted or unsubstituted alkenyl group include a vinyl group, allyl group, propenyl group, butenyl group, hexenyl group, cyclohexenyl group and the like.

As a substituted or unsubstituted oxoalkyl group, 2-oxocyclopentyl group, 2-oxocyclohexyl group, 2-oxopropyl group, 2-oxoethyl group, 2-cyclopentyl-2-oxoethyl group, 2-cyclohexyl-2 -Oxoethyl group, 2- (4-methylcyclohexyl) -2-oxoethyl group, etc. are mentioned.

As a substituted or unsubstituted aryl group, a phenyl group, a naphthyl group, thienyl group, etc., 4-hydroxyphenyl group, 4-methoxyphenyl group, 3-methoxyphenyl group, 2-methoxyphenyl group, 4-ethoxyphenyl group, 4 alkoxyphenyl groups such as -tert-butoxyphenyl group and 3-tert-butoxyphenyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-tert-butylphenyl group, 4-n- Alkylphenyl groups such as butylphenyl group and 2,4-dimethylphenyl group, alkylnaphthyl groups such as methylnaphthyl group and ethyl naphthyl group, alkoxynaphthyl groups such as methoxynaphthyl group and ethoxynaphthyl group, dimethylnaphthyl group and diethylnaphthyl group And dialkoxy naphthyl groups such as dialkyl naphthyl groups, dimethoxynaphthyl groups and diethoxy naphthyl groups.

As a substituted or unsubstituted aralkyl group, a benzyl group, 1-phenylethyl group, 2-phenylethyl group, etc. are mentioned.

Examples of the substituted or unsubstituted aryl oxoalkyl group include 2-phenyl-2-oxoethyl group, 2- (1-naphthyl) -2-oxoethyl group and 2- (2-naphthyl) -2-oxoethyl group. An aryl-2-oxoethyl group etc. are mentioned.

In addition, when any two or more of R <^2> , R <^3> and R <^4> combine with each other, and form a cyclic structure with a sulfur atom, the following can be illustrated concretely, It is not limited to this.

(Wherein R ⁴ is the same as above)

More specifically, when sulfonium cation is represented, triphenylsulfonium, 4-hydroxyphenyldiphenylsulfonium, bis (4-hydroxyphenyl) phenylsulfonium, tris (4-hydroxyphenyl) sulfonium, 4-tert -Butoxyphenyldiphenylsulfonium, bis (4-tert-butoxyphenyl) phenylsulfonium, tris (4-tert-butoxyphenyl) sulfonium, 3-tert-butoxyphenyldiphenylsulfonium, bis ( 3-tert-butoxyphenyl) phenylsulfonium, tris (3-tert-butoxyphenyl) sulfonium, 3,4-di-tert-butoxyphenyldiphenylsulfonium, bis (3,4-di-tert -Butoxyphenyl) phenylsulfonium, tris (3,4-di-tert-butoxyphenyl) sulfonium, diphenyl (4-thiophenoxyphenyl) sulfonium, 4-tert-butoxycarbonylmethyloxy Phenyldiphenylsulfonium, tris (4-tert-butoxycarbonylmethyloxyphenyl) sulfonium, (4-tert-butoxyphenyl) bis (4-dimethylaminophenyl) sulfonium, tris (4-dimethylaminophenyl ) Sulfonium, 2-naphthyldiphenylsulfonium, (4-hydroxy-3,5-dimethylphenyl) diphenyl Phonium, (4-n-hexyloxy-3,5-dimethylphenyl) diphenylsulfonium, dimethyl (2-naphthyl) sulfonium, 4-hydroxyphenyldimethylsulfonium, 4-methoxyphenyldimethylsulfonium , Trimethylsulfonium, 2-oxocyclohexylcyclohexylmethylsulfonium, trinaphthylsulfonium, tribenzylsulfonium, diphenylmethylsulfonium, dimethylphenylsulfonium, 2-oxo-2-phenylethylthiacyclopentanium , Diphenyl 2-thienylsulfonium, 4-n-butoxynaphthyl-1-thiacyclopentanium, 2-n-butoxynaphthyl-1-thiacyclopentanium, 4-methoxynaphthyl-1- Thiacyclopentanium, 2-methoxynaphthyl-1- thiacyclopentanium, and the like. More preferably triphenylsulfonium, 4-tert-butylphenyldiphenylsulfonium, 4-tert-butoxyphenyldiphenylsulfonium, tris (4-tert-butylphenyl) sulfonium, and tris (4-tert- Butoxyphenyl) sulfonium, dimethylphenylsulfonium, etc. are mentioned.

As said C1-C10 linear, branched or cyclic divalent hydrocarbon group represented by A <^1> , the following can be illustrated specifically ,.

(Indicated by broken line in formula)

Although the following can be illustrated specifically as a repeating unit represented by the said Formula (1), It is not limited to this.

(Wherein R ¹ is the same as above)

(Wherein R ¹ is the same as above)

(Wherein R ¹ is the same as above)

(Wherein R ¹ is the same as above)

(Wherein R ¹ is the same as above)

(Wherein R ¹ is the same as above)

Here, the monomer for obtaining the repeating unit represented by General formula (1) in the high molecular compound of this invention is a novel substance represented by following General formula (1a).

(Wherein R ¹ represents any ^one of a hydrogen atom, a fluorine atom, a methyl group and a trifluoromethyl group, and R ² , R ³ and R ⁴ each independently represent a substituted or unsubstituted straight chain having 1 to 10 carbon atoms, Any of branched or cyclic alkyl, alkenyl and oxoalkyl groups, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, an aralkyl group and an aryloxoalkyl group, or R ² , R ³ and Any two or more of R ⁴ may be bonded to each other to form a ring together with a sulfur atom in the formula, X ¹ represents O or CH ₂ , and A ¹ is linear, branched or cyclic having 1 to 10 carbon atoms. Represents a divalent hydrocarbon group, B ¹ represents an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 18 carbon atoms, which may include a hetero atom other than fluorine, and k ¹ represents an integer of 0 or 1)

Here, although the method for obtaining monomer (1a) is illustrated in the following reaction formula, it is not limited to this. Hereinafter, the broken line used in a formula represents a bond.

(In formula, R <^1> -R <^4> , X <^1> , A <^1> , B <^1> and k <^1> are the same as the above, X <^2> represents a halogen atom, a hydroxyl group, an alkoxy group, or the substituent represented by following General formula (10), M ⁺ represents lithium ions, sodium ions, potassium ions, substituted or unsubstituted ammonium ions, and X ^3- represents halide ions or methyl sulfate ions)

Wherein R ¹ , A ¹ and k ¹ are the same as above.

Further, it is possible, if in Formula (1a) of k ¹ is 1, using the other method shown below to obtain the compound (4) in the reaction scheme.

(Wherein, R ^1, X ¹ and A ¹ is as defined above, and X ⁴ represents a halogen atom, X ⁵ represents a halogen atom, a hydroxyl group or an alkoxy group, M ^{a +} is a lithium ion, a sodium ion, a potassium ion , Magnesium ions, calcium ions or substituted or unsubstituted ammonium ions)

Step (i) is a step of inducing ester (4) by reaction of hydroxylactone (2) and esterification agent (3). In addition, the synthesis | combining method of hydroxylactone (2) is disclosed by Unexamined-Japanese-Patent No. 2000-159758 and Unexamined-Japanese-Patent No. 4539865.

The reaction proceeds easily by a known method, but as the esterifying agent (3), an acid chloride (when X ² is a chlorine atom in formula (3)) or an acid anhydride (in formula (3), X ² is represented by a formula ( Preference is given to a substituent represented by 10)) or a carboxylic acid (in formula (3), where X ² is a hydroxyl group).

When acid chloride or acid anhydride is used, hydroxylactone compound (2) and acrylic acid chloride, methacrylic acid in solvents or solvents such as methylene chloride, toluene, hexane, diethyl ether, tetrahydrofuran and acetonitrile Corresponding acid chlorides or acid anhydrides such as chlorides, acrylic anhydrides and methacrylic anhydrides, and bases such as triethylamine, pyridine and 4-dimethylaminopyridine are added sequentially or simultaneously, and cooled or heated as necessary. It is preferable to carry out.

In addition, when using a carboxylic acid, hydroxylactone (2) and corresponding carboxylic acids, such as acrylic acid and methacrylic acid, are heated in the presence of an acid catalyst in solvents, such as toluene and hexane, and generate | occur | produce as needed. It is preferable to remove water to be made out of the system and the like. As an acid catalyst to be used, inorganic acids, such as hydrochloric acid, a sulfuric acid, nitric acid, a perchloric acid, organic acids, such as p-toluenesulfonic acid and benzenesulfonic acid, etc. are mentioned, for example.

Step (ii) is a step of deprotecting the tert-butyl ester portion of ester (4) with formic acid to obtain carboxylic acid (5). Carboxylic acid (5) can be obtained by dissolving ester (4) as a solvent and stirring, cooling or heating as needed.

Step (iii) is a step of inducing carboxylic acid (5) to the corresponding acid chloride (6). The reaction is preferably carried out by sequentially or simultaneously adding a chlorinating agent such as oxalyl dichloride in a solvent such as methylene chloride, toluene, hexane, diethyl ether, tetrahydrofuran, acetonitrile and cooling or heating as necessary. .

Step (iv) is a step of obtaining onium salt (8) by nucleophilic substitution reaction of acid chloride (6) and sulfoalcohol (7). The reaction can be carried out according to a conventional method, and it is preferable to add an acid chloride (6), a sulfoalcohol (7) and a base in a solvent sequentially or simultaneously, and to carry out cooling or heating as necessary. As a solvent which can be used for reaction, ether, such as water, tetrahydrofuran, diethyl ether, diisopropyl ether, di-n-butyl ether, 1, 4- dioxane, n-hexane, n-heptane, benzene Hydrocarbons such as toluene and xylene, aprotic polar solvents such as acetonitrile, dimethyl sulfoxide (DMSO) and N, N-dimethylformamide (DMF), and chlorine organic solvents such as methylene chloride, chloroform and carbon tetrachloride. Can be mentioned. These solvents can be appropriately selected and used according to the reaction conditions, and can be used alone or in combination of two or more thereof. Moreover, as a base which can be used for the reaction shown by said step (iv), For example, amines, such as ammonia, triethylamine, pyridine, lutidine, collidine, N, N- dimethylaniline, sodium hydroxide, potassium hydroxide, Hydroxides, such as tetramethylammonium hydroxide, Carbonate, such as potassium carbonate and sodium hydrogencarbonate, etc. are mentioned. These bases can be used individually by 1 type or in mixture of 2 or more types.

Step (v) is a step of obtaining a sulfonium salt (1a) having a polymerizable anion by ion exchange reaction between the onium salt (8) and the sulfonium salt (9). After the reaction of step (iv) is carried out, the onium salt (8) may be one that has been isolated through a conventional aqueous post-treatment, or may be one that does not undergo post-treatment after the reaction is stopped.

In the case of using the isolated onium salt (8), ethers such as water, tetrahydrofuran, diethyl ether, diisopropyl ether, di-n-butyl ether and 1,4-dioxane Aprotic polar solvents such as hydrocarbons such as n-hexane, n-heptane, benzene, toluene and xylene, acetonitrile, dimethyl sulfoxide (DMSO) and N, N-dimethylformamide (DMF) The reaction mixture can be obtained by dissolving in a chlorine-based organic solvent such as methylene, chloroform, carbon tetrachloride or the like, mixing with the sulfonium salt (9), and cooling or heating as necessary. The sulfonium salt (1a) having a polymerizable anion can be obtained from the reaction mixture by ordinary aqueous work-up, and can be purified according to conventional methods such as distillation, recrystallization, chromatography, etc. as necessary.

After stopping the reaction for synthesizing the onium salt (8), in the case of using the one which has not been specifically subjected to post-treatment, the sulfonium salt (9) is added to the mixture which stopped the synthesis reaction of the onium salt (8), and By cooling or heating depending on the reaction mixture can be obtained. At this time, ethers such as water, tetrahydrofuran, diethyl ether, diisopropyl ether, di-n-butyl ether, 1,4-dioxane, n-hexane, n-heptane, benzene, toluene, Hydrocarbons such as xylene, aprotic polar solvents such as acetonitrile, dimethyl sulfoxide (DMSO) and N, N-dimethylformamide (DMF), and chlorine-based organic solvents such as methylene chloride, chloroform and carbon tetrachloride can be added. It may be. The sulfonium salt (1a) having a polymerizable anion can be obtained from the reaction mixture by ordinary aqueous work-up, and can be purified according to conventional methods such as distillation, recrystallization, chromatography, etc. as necessary.

Steps (vi) and (vii) are other methods of obtaining ester (4) in the reaction scheme when k ¹ is 1 in the formula (1a).

Step (vi) is a reaction for obtaining the haloester (12) by the reaction of the hydroxylactone (2) and the esterifying agent (11). The reaction proceeds easily by a known method, but as the esterifying agent (11), an acid chloride (if X ⁵ is a chlorine atom in formula (11)) or a carboxylic acid (X ⁵ in formula (11) is a hydroxyl group) ) Is particularly preferred. In the case of using an acid chloride, solvents or corresponding acid chlorides such as hydroxylactone (2), 2-chloroacetic acid chloride, 3-chloropropionic acid chloride, and the like in a solvent such as methylene chloride, acetonitrile, toluene and hexane It is preferable to add a base such as ethylamine, pyridine, 4-dimethylaminopyridine or the like sequentially or simultaneously, and to carry out cooling or heating as necessary. In the case of using carboxylic acid, hydroxylactone (2) and the corresponding carboxylic acid such as 2-chloroacetic acid and 3-chloropropionic acid are heated in the presence of an acid catalyst in a solvent such as toluene or hexane, It is preferable to remove water produced | generated as needed out of system and the like. As an acid catalyst to be used, inorganic acids, such as hydrochloric acid, a sulfuric acid, nitric acid, a perchloric acid, organic acids, such as p-toluenesulfonic acid and benzenesulfonic acid, etc. are mentioned, for example. The reaction time is preferably in terms of the yield in order to complete the reaction by tracking the reaction by gas chromatography (GC) or silica gel thin layer chromatography (TLC), but it is usually about 0.5 to 24 hours. The haloester (12) can be obtained from the reaction mixture by ordinary aqueous work-up, and can be purified according to conventional methods such as distillation, chromatography, and recrystallization as necessary.

Step (vii) is a reaction induced into ester (14) by reaction of haloester (12) and carboxylate compound (13).

The reaction in step (vii) can be carried out according to a conventional method. As the carboxylate compound (13), commercially available carboxylate compounds such as various carboxylate metal salts may be used as they are, and carboxylate compounds may be used in the reaction system from corresponding carboxylic acids and bases such as methacrylic acid and acrylic acid. It can also manufacture and use. It is preferable that the usage-amount of a carboxylate compound (13) shall be 0.5-10 mol, especially 1.0-3.0 mol with respect to 1 mol of haloesters (12) which are raw materials. If the amount is less than 0.5 mole, the yield may be greatly reduced because the raw material remains in a large amount. If the amount is more than 10 mole, the cost may be disadvantageous due to an increase in the raw material cost and a decrease in the yield of the cauldron. As a base which can be used when manufacturing a carboxylate compound in a reaction system from a corresponding carboxylic acid and a base, For example, amines, such as ammonia, triethylamine, pyridine, lutidine, collidine, N, N- dimethylaniline, etc. ; Hydroxides such as sodium hydroxide, potassium hydroxide and tetramethylammonium hydroxide; Carbonates such as potassium carbonate and sodium bicarbonate; Metals such as sodium; Metal hydrides such as sodium hydride; Metal alkoxides such as sodium methoxide and potassium t-butoxide; Organic metals such as butyllithium and ethyl magnesium bromide; It can select from metal amides, such as lithium diisopropylamide, and can use individually or in mixture of 2 or more types. It is preferable that the usage-amount of a base shall be 0.2-10 mol, especially 0.5-2.0 mol with respect to 1 mol of corresponding carboxylic acids. If the amount is less than 0.2 mole, a large amount of carboxylic acid becomes useless, which may be disadvantageous in terms of cost. If the amount is more than 10 mole, the yield may be greatly reduced due to the increase in side reactions. The reaction time is preferably in terms of yield in that the reaction is completed by gas chromatography (GC) or silica gel thin layer chromatography (TLC) to complete the reaction, but it is usually about 0.5 to 24 hours. The sulfonium salt (1a) having a polymerizable anion can be obtained from the reaction mixture by ordinary aqueous work-up, and can be purified according to conventional methods such as distillation, chromatography, and recrystallization as necessary.

The repeating unit represented by the formula (1) contained in the polymer compound of the present invention has a sulfonium salt structure of sulfonic acid in which B ¹ is not substituted with fluorine, and has a lactone structure. Therefore, when used as the base resin of the chemically amplified resist material, it is possible to appropriately control the movement and diffusion of the strong acid generated from the acid generator, and it can be expected to provide high substrate adhesion of the resist film.

In the polymer compound of the present invention, a repeating unit having an acid labile group can coexist in addition to the repeating unit represented by the formula (1). As a repeating unit which has this acid labile group, the repeating unit which has an acid labile group represented by following General formula (2A) is mentioned.

(Wherein R ¹ is the same as above and XA represents an acid labile group)

Hereinafter, the acid labile unit will be described. The high molecular compound which further contains the repeating unit represented by the said General formula (2A) decomposes by the action of an acid, produces | generates a carboxylic acid, and becomes a high molecular compound which becomes alkali-soluble. As the acid labile group XA, one represented by the following formula can be used.

In the formula, the dashed line represents a bond. R ^L01 and R ^L02 represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. Specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, cyclopentyl group, cyclohexyl group, 2-ethylhexyl group, n-octyl group, and Adamman Til group etc. can be illustrated. R ^L03 represents a monovalent hydrocarbon group which may have a hetero atom such as an oxygen atom having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, and a linear, branched or cyclic alkyl group, a part of these hydrogen atoms being a hydroxyl group, The thing substituted by the alkoxy group, oxo group, amino group, alkylamino group, etc. are mentioned. Specifically, as a linear, branched or cyclic alkyl group, the same thing as said ^RL01 , ^RL02 can be illustrated, and the following group etc. can be illustrated as a substituted alkyl group.

(Indicated by broken line in formula)

R ^L01 and R ^L02 , R ^L01 and R ^L03 , R ^L02 and R ^L03 may be bonded to each other to form a ring together with a carbon atom or an oxygen atom to which they are bonded, and in the case of forming a ring, participate in ring formation. R ^L01 and R ^L02 , R ^L01 and R ^L03 or R ^L02 and R ^L03 each represent a linear or branched alkylene group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms.

R ^L04 , R ^L05 and R ^L06 each independently represent a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms. Specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, cyclopentyl group, cyclohexyl group, 2-ethylhexyl group, n-octyl group, 1- Adamantyl group, 2-adamantyl group, etc. can be illustrated.

R ^L07 represents a linear, branched or cyclic alkyl group which may be substituted with 1 to 10 carbon atoms, or an aryl group which may be substituted with 6 to 20 carbon atoms. Specific examples of the alkyl group which may be substituted include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, tert-amyl group, n-pentyl group and n-hexyl group Linear, branched or cyclic alkyl groups such as cyclopentyl group, cyclohexyl group and bicyclo [2.2.1] heptyl group, and some of these hydrogen atoms are hydroxyl group, alkoxy group, carboxyl group, alkoxycarbonyl group, oxo group, amino group The group substituted with the alkylamino group, the cyano group, the mercapto group, the alkylthio group, the sulfo group, etc., or the group by which some of these methylene groups were substituted by the oxygen atom or the sulfur atom, etc. can be illustrated. Specific examples of the aryl group which may be substituted include phenyl group, methylphenyl group, naphthyl group, anthryl group, phenanthryl group, pyrenyl group and the like. In the formula (L3), m is 0 or 1, n is any one of 0, 1, 2, 3, and is a number that satisfies 2m + n = 2 or 3.

R ^L08 represents a linear, branched or cyclic alkyl group which may be substituted with 1 to 10 carbon atoms, or an aryl group which may be substituted with 6 to 20 carbon atoms. Specifically, the same thing as R ^L07 can be exemplified. R ^L09 to R ^L18 each independently represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 15 carbon atoms. Specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, tert-amyl group, n-pentyl group, n-hexyl group, n-octyl group, n Linear, branched or such as nonyl, n-decyl, cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl or cyclohexylbutyl groups A cyclic alkyl group, and some of these hydrogen atoms are substituted by hydroxyl group, alkoxy group, carboxyl group, alkoxycarbonyl group, oxo group, amino group, alkylamino group, cyano group, mercapto group, alkylthio group, sulfo group, etc. can be illustrated. have. R ^L09 and R ^L10 , R ^L09 and R ^L11 , R ^L09 and R ^L12 , R ^L10 and R ^L12 , R ^L11 and R ^L12 , R ^L13 and R ^L14 , R ^L15 and R ^L16 or R ^L16 and R ^L17 May bind to form a ring, in which case R ^L09 and R ^L10 , R ^L09 and R ^L11 , R ^L09 and R ^L12 , R ^L10 and R ^L12 , R ^L11 and R ^L12 , R ^L13 and R ^L14 , R ^L15 and R ^L16 or R ^L16 and R ^L17 represent a divalent hydrocarbon group having 1 to 15 carbon atoms, and specifically exemplify one having a hydrogen atom removed from those exemplified in the monovalent hydrocarbon group. can do. In addition, R ^L09 and R ^L11 , R ^L11 and R ^L17, or R ^L15 and R ^L17 may be bonded to adjacent carbons without passing through each other to form a double bond.

R ^L19 represents a linear, branched or cyclic alkyl group which may be substituted with 1 to 10 carbon atoms, or an aryl group which may be substituted with 6 to 20 carbon atoms, and specifically, the same as those of R ^L07 may be exemplified. have.

R ^L20 represents a linear, branched or cyclic alkyl group which may be substituted with 1 to 10 carbon atoms, or an aryl group which may be substituted with 6 to 20 carbon atoms, and specifically, the same group as R ^L07 may be exemplified. have.

X represents a bivalent group which, together with the carbon atom to which it is bonded, forms a substituted or unsubstituted cyclopentane ring, cyclohexane ring or norbornane ring which may include a double bond. R ^L21 and R ^L22 each independently represent a hydrogen atom or a linear, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms. R ^L21 and R ^L22 may be bonded to each other to form a ring together with the carbon atom to which they are bonded, and in this case, represents a divalent group that forms a substituted or unsubstituted cyclopentane ring or cyclohexane ring. p represents 1 or 2.

R ^L23 represents a linear, branched or cyclic alkyl group which may be substituted with 1 to 10 carbon atoms, or an aryl group which may be substituted with 6 to 20 carbon atoms, and specifically, the same groups as R ^L07 may be exemplified. have.

Y represents the bivalent group which forms the substituted or unsubstituted cyclopentane ring, cyclohexane ring, or norbornane ring with the carbon atom to which it couple | bonds. R ^L24 and R ^L25 each independently represent a hydrogen atom or a linear, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms. R ^L24 and R ^L25 may be bonded to each other to form a ring together with the carbon atom to which they are bonded, in which case a divalent group is used to form a substituted or unsubstituted cyclopentane ring or cyclohexane ring. q represents 1 or 2.

R ^L26 represents a linear, branched or cyclic alkyl group which may be substituted with 1 to 10 carbon atoms, or an aryl group which may be substituted with 6 to 20 carbon atoms, and specifically, the same groups as R ^L07 may be exemplified. have.

Z represents a bivalent group which forms the substituted or unsubstituted cyclopentane ring, cyclohexane ring, or norbornane ring with the carbon atom to which it couple | bonds. R ^L27 and R ^L28 each independently represent a hydrogen atom or a linear, branched or cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms. R <^L27> and R <^L28> may combine with each other, and may form a ring with the carbon atom to which they couple | bond, In this case, they represent the bivalent group which forms a substituted or unsubstituted cyclopentane ring or a cyclohexane ring.

Specific examples of the linear or branched group among the acid labile groups represented by the general formula (L1) include the following groups.

(Indicated by broken line in formula)

As an annular thing among the acid labile groups represented by the said general formula (L1), specifically, the tetrahydrofuran-2-yl group, 2-methyl tetrahydrofuran-2-yl group, tetrahydropyran-2-yl group, 2-methyl tetra Hydropyran-2-yl group etc. can be illustrated.

As an acid labile group of the said general formula (L2), a tert- butyl group, a tert-amyl group, the following group, etc. can be illustrated specifically ,.

(Indicated by broken line in formula)

As an acid labile group of the said general formula (L3), 1-methylcyclopentyl group, 1-ethylcyclopentyl group, 1-n-propylcyclopentyl group, 1-isopropylcyclopentyl group, 1-n-butylcyclophene specifically, Tyl group, 1-sec-butylcyclopentyl group, 1-cyclohexylcyclopentyl group, 1- (4-methoxy-n-butyl) cyclopentyl group, 1- (bicyclo [2.2.1] heptan-2- 1) cyclopentyl group, 1- (7-oxabicyclo [2.2.1] heptan-2-yl) cyclopentyl group, 1-methylcyclohexyl group, 1-ethylcyclohexyl group, 3-methyl-1-cyclo Penten-3-yl group, 3-ethyl-1-cyclopenten-3-yl group, 3-methyl-1-cyclohexen-3-yl group, 3-ethyl-1-cyclohexen-3-yl group, etc. can be illustrated. .

As the acid labile group of the general formula (L4), groups represented by the following general formulas (L4-1) to (L4-4) are particularly preferable.

In the formulas (L4-1) to (L4-4), the broken line indicates the bonding position and the bonding direction. R ^L41 each independently represents a linear, branched or cyclic alkyl group which may be substituted with 1 to 10 carbon atoms, or an aryl group which may be substituted with 6 to 20 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, Isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, tert-amyl group, n-pentyl group, n-hexyl group, cyclopentyl group, cyclohexyl group, etc. can be illustrated.

In the above formulas (L4-1) to (L4-4), enantiomers and diastereomers may be present, but the above formulas (L4-1) to (L4-4) are three-dimensional. Representatively all of the isomers are shown. These stereoisomers may be used alone or as a mixture.

For example, the said general formula (L4-3) shall represent the 1 type or mixture of 2 types chosen from group represented by the following general formula (L4-3-1), (L4-3-2).

^Wherein R ^L41 is as defined above.

In addition, the said general formula (L4-4) shall represent the 1 type, or 2 or more types of mixtures chosen from the group represented by the following general formula (L4-4-1)-(L4-4-4).

^Wherein R ^L41 is as defined above.

The above general formulas (L4-3-1), (L4-3-2) and (L4-4-1) to (L4-4-4) also represent a mixture of enantio and enantio isomers thereof. Shall be.

Also, the bonding directions of the formulas (L4-1) to (L4-4), (L4-3-1), (L4-3-2) and (L4-4-1) to (L4-4-4) High reactivity in the acid catalyzed desorption reaction is realized in the exo side with respect to each of the bicyclo [2.2.1] heptane rings (see Japanese Patent Laid-Open No. 2000-336121). In the preparation of monomers having tertiary exo-alkyl groups having these bicyclo [2.2.1] heptane skeletons as substituents, endo-alkyl groups represented by the following formulas (L4-1-endo) to (L4-4-endo) Although it may contain the monomer substituted by, in order to implement | achieve favorable reactivity, it is preferable that an exo ratio is 50% or more, and it is more preferable that an exo ratio is 80% or more.

^Wherein R ^L41 is as defined above.

As an acid labile group of the said general formula (L4), the following group etc. can be illustrated specifically ,.

(Indicated by broken line in formula)

As an acid labile group of the said general formula (L5), the following group etc. can be illustrated specifically ,.

(Indicated by broken line in formula)

As an acid labile group of the said general formula (L6), the following group etc. can be illustrated specifically ,.

(Indicated by broken line in formula)

As an acid labile group of the said general formula (L7), the following group etc. can be illustrated specifically ,.

(Indicated by broken line in formula)

As an acid labile group of the said general formula (L8), the following group etc. can be illustrated specifically ,.

(Indicated by broken line in formula)

Although the following can be illustrated specifically as a repeating unit represented by the said General formula (2A), It is not limited to these.

When the repeating unit represented by the general formula (1) of the present invention coexists with the repeating unit represented by the general formula (2A), not only functions of acid movement and diffusion control but also acid itself are selected by the acid labile unit. It is also possible to function as a generating unit.

In the polymer compound of the present invention, the repeating units represented by the following formulas (2B) to (2E) can coexist in addition to the repeating units represented by the formulas (1) and (2A).

(In formula, R <^1> is the same as the above, XB and XC respectively independently represent a single bond or a C1-C4 linear or branched bivalent hydrocarbon group, YA represents a substituent which has a lactone structure, ZA Represents a hydrogen atom or a fluoroalkyl group having 1 to 15 carbon atoms or a fluoroalcohol containing substituent having 1 to 15 carbon atoms, k ^1A represents an integer of 1 to 3, R ⁵ , R ⁶ and R ⁷ is each independently a substituted or unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group or an oxoalkyl group, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, an aralkyl group or an aryloxoalkyl group. Or any two or more of R ⁵ , R ⁶ and R ⁷ may combine with each other to form a ring together with a sulfur atom in the formula)

As a repeating unit represented by General formula (2B), the following are mentioned specifically ,.

As a repeating unit represented by general formula (2C), the following are mentioned specifically ,.

As a repeating unit represented by general formula (2D), the following are mentioned specifically ,.

As a repeating unit represented by general formula (2E), the following are mentioned specifically ,.

(Wherein R ¹ is the same as above)

In addition to the repeating unit (1) of this invention, the high molecular compound which suitably combined the acid labile unit represented by the said General formula (2A), or the repeating unit represented by General formula (2B)-(2E) as a resist base resin is used. By using it, it is possible to obtain a chemically amplified resist material which is high resolution and resistant to pattern collapse.

When synthesizing the high molecular compound of the present invention, radical polymerization using an initiator such as 2,2'-azobisisobutyronitrile (hereinafter abbreviated as AIBN), ion polymerization (anion polymerization) using alkyl lithium, etc. It is possible to use the general polymerization method of, and these polymerization can be carried out according to the conventional method. Among these, it is preferable to manufacture the synthesis | combination of the high molecular compound of this invention by radical polymerization. In this case, the polymerization conditions are governed by the kind and amount of the initiator, temperature, pressure, concentration, solvent, additives and the like.

Although it does not specifically limit as a radical polymerization initiator, For example, AIBN, 2,2'- azobis (4-methoxy-2, 4- dimethylvaleronitrile), 2,2'- azobis (2, 4- dimethyl) Azo compounds such as valeronitrile), 2,2'-azobis (2,4,4-trimethylpentane), 2,2'-azobis (isobutyric acid) dimethyl, tert-butylperoxy pivalate, lau Peroxide-based compounds such as loyl peroxide, benzoyl peroxide, tert-butylperoxylaurate, water-soluble polymerization initiators such as potassium persulfate, and combinations of peroxides such as potassium persulfate and hydrogen peroxide and reducing agents such as sodium sulfite Examples thereof include redox initiators. Although the usage-amount of a polymerization initiator can be changed suitably according to a kind, superposition | polymerization conditions, etc., 0.001-10 mol%, especially 0.01-6 mol% are employ | adopted with respect to the monomer total amount to superpose | polymerize normally.

When synthesizing the polymer compound of the present invention, a known chain transfer agent such as dodecyl mercaptan or 2-mercaptoethanol may be used in combination for adjusting the molecular weight. In this case, it is preferable that the addition amount of these chain transfer agents is 0.01-10 mol% with respect to the total mole number of the monomer to superpose | polymerize.

When synthesize | combining the high molecular compound of this invention, the polymerizable monomer corresponding to the repeating unit represented by General formula (1) (2A)-(2E) is mixed, and superposition | polymerization is performed by adding the initiator and chain transfer agent mentioned above.

Here, with respect to the repeating units (1) and (2A) to (2E) in the polymer compound of the present invention,

The total mole number of the monomer corresponding to the unit of formula 1 is represented by U1,

The total moles of monomers corresponding to the units of the formulas (2A) to (2E) are U2, U3, U4, U5, U6, respectively, and U1 + U2 + U3 + U4 + U5 + U6 = 1 (100 mol%). In one case, the rate of introduction of each repeating unit

0 <U1 <1, 0 <U2 <0.9, 0≤U3≤0.3, 0≤U4 <0.7, 0≤U5≤0.3, 0≤U6≤0.15, 0≤U2 + U3 + U4 + U5 + U6≤0.7 It is preferable.

When superposing | polymerizing, a solvent can also be used as needed. The polymerization solvent is preferably one which does not inhibit the polymerization reaction, and typical examples thereof include esters such as ethyl acetate, n-butyl acetate and γ-butyrolactone, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, toluene, Aliphatic or aromatic hydrocarbons such as xylene and cyclohexane, alcohols such as isopropyl alcohol and ethylene glycol monomethyl ether, ether solvents such as diethyl ether, dioxane and tetrahydrofuran can be used. These solvents may be used alone or in combination of two or more thereof. The usage-amount of a polymerization solvent can be suitably changed with polymerization conditions, such as target polymerization degree (molecular weight), the addition amount of an initiator, polymerization temperature, and the density | concentration of the monomer to superpose | polymerize normally is 0.1-95 mass%, especially 5-90 mass% The solvent is added so that

Although the reaction temperature of a polymerization reaction changes suitably according to the kind of polymerization initiator or the boiling point of a solvent, Usually, 20-200 degreeC is preferable and 50-140 degreeC is especially preferable. The reaction container used for such a polymerization reaction is not specifically limited.

As a method of removing the organic solvent or water which is a medium from the solution or dispersion of the polymer thus obtained, any known method can be used, but there are methods such as reprecipitation filtration or heat extraction under reduced pressure.

This invention provides the chemically amplified resist material characterized by containing (A) the high molecular compound of this invention, (B) organic solvent, (C) photoacid generator, and (D) basic compound.

About the (B) organic solvent used by this invention, it is detailed in description of Unexamined-Japanese-Patent No. 2009-269953. (B) diethylene glycol dimethyl ether, 1-ethoxy-2-propanol, propylene glycol monomethyl ether acetate, cyclohexanone, 4-butyrolactone and the like, which have the highest solubility of the acid generator in the resist component among the organic solvents; Mixed solvents are preferably used.

As for the usage-amount of the organic solvent, 200-5,000 mass parts, especially 400-3,000 mass parts is preferable with respect to 100 mass parts of base resins.

In order to function as a chemically amplified resist material, the compound ((C) photoacid generator) which generate | occur | produces an acid by exposure of a high energy ray may be included. As a component of the (C) photoacid generator, any compound may be used as long as it is a compound that generates an acid by irradiation with high energy ray, but preferred photoacid generators include sulfonium salt, iodonium salt, sulfonyldiazomethane, and N-sulfonyloxy. Mead, an oxime-O-sulfonate type acid generator, etc. are mentioned, As an example, it is described in Unexamined-Japanese-Patent No. 2010-002599 (0108)-(0116) paragraph.

 Especially as a photo-acid generator, what is represented by following General formula (C) -1 is used preferably.

(Wherein R ⁴⁰⁵ , R ⁴⁰⁶ , R ⁴⁰⁷ each independently represents a hydrogen atom or a linear, branched or cyclic monovalent hydrocarbon group having 1 to 20 carbon atoms, which may include a hetero atom, in particular an alkyl group or an alkoxy group) R ⁴⁰⁸ represents a straight chain, branched or cyclic monovalent hydrocarbon group having 7 to 30 carbon atoms which may contain a hetero atom)

The addition amount of the photoacid generator in the chemically amplified resist material of the present invention may be any amount as long as it does not interfere with the effects of the present invention, but may be 0 to 40 parts by mass relative to 100 parts by mass of the base resin in the chemically amplified resist material. In particular, it is preferable that it is 0.1-40 mass parts, Furthermore, it is 0.1-20 mass parts. If the ratio of the photo-acid generator is within such a range, it is preferable because there is no fear of deterioration of resolution and foreign matters at the time of development / resist release. The photoacid generators may be used alone or in combination of two or more thereof. Moreover, the transmittance | permeability in a resist film can also be controlled with the addition amount using the photoacid generator with low transmittance | permeability in an exposure wavelength.

In addition, the (D) basic compound may be added to the chemically amplified resist material of the present invention. Examples of the basic compound (D) include primary, secondary and tertiary aliphatic amines, hybrid amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxyl group, nitrogen-containing compounds having a sulfonyl group, and nitrogen-containing compounds having a hydroxyl group. Compounds, nitrogen-containing compounds having hydroxyphenyl groups, alcoholic nitrogen-containing compounds, amides, imides, carbamates, ammonium salts and the like, and the like, and specific examples thereof are described in Japanese Patent Laid-Open No. 2009-269953. have.

In this case, a basic compound can be used individually by 1 type or in combination of 2 or more types, and the compounding quantity does not matter as long as it is a range which does not prevent the effect of the repeating unit represented by the said General formula (1) of this invention, 0.001-12 mass parts is preferable with respect to 100 mass parts of resin, Especially 0.01-8 mass parts is preferable.

The chemically amplified resist material of the present invention may further contain any one or more of an organic acid derivative and / or a fluorine-substituted alcohol, a weight average molecular weight of 3,000 or less dissolution inhibitor, and a surfactant.

The addition of an organic acid derivative and / or a fluorine-substituted alcohol and a compound having a weight average molecular weight of 3,000 or less (dissolution inhibiting agent) is optional, but the compounds described in JP2009-269953A can be referred to.

About surfactant, the (E) definition component described in Unexamined-Japanese-Patent No. 2009-269953 can be referred. In addition, Japanese Patent Laid-Open No. 2008-122932, Japanese Patent Laid-Open No. 2010-134012, Japanese Patent Laid-Open No. 2010-107695, Japanese Patent Laid-Open No. 2009-276363, 2009-192784, 2009- 191151 and Unexamined-Japanese-Patent No. 2009-98638 can also be referred to, and can use a conventional surfactant and alkali-soluble surfactant.

The addition amount of the said surfactant is 0.001-20 mass parts with respect to 100 mass parts of base resin of a resist material, Preferably it is the range of 0.01-10 mass parts. These are detailed in Unexamined-Japanese-Patent No. 2007-297590.

Next, the present invention includes a step of applying the above-described chemically amplified resist material on a substrate, a step of exposing with a high energy ray through a photomask after heat treatment, and a step of developing using a developer. A pattern forming method is provided.

Further, in the present invention, a process of applying the above-described chemically amplified resist material on a substrate, a process of applying a protective film insoluble in water and soluble in an alkaline developer after heat treatment, and inserting water between the substrate and the projection lens Thereby provides a pattern forming method comprising the step of exposing to a high energy ray through a photomask, and the step of developing using a developer.

In detail, in order to form a pattern using the resist material of the present invention, a well-known lithography technique may be employed, and for example, a substrate for manufacturing an integrated circuit (Si, SiO ₂ , SiN, SiON, TiN, WSi, BPSG, SOG, organic anti-reflective film, etc.) or a substrate for mask circuit manufacturing (Cr, CrO, CrON, MoSi, etc.) by coating such as spin coating to a film thickness of 0.05 to 2.0 ㎛, 60 on a hot plate Prebaking is carried out at -150 ° C for 1 to 10 minutes, preferably at 80 to 140 ° C for 1 to 5 minutes. Subsequently, a mask for forming a target pattern is inserted on the resist film, and high energy rays such as far ultraviolet rays, excimer lasers, X-rays, and electron beams are exposed at an exposure dose of 1 to 200 mJ / cm ² , preferably 10 to 100 mJ. Investigate to be / cm ² . Or the electron beam is drawn directly, without going through the mask for pattern formation. Subsequently, it is exposed to a hot plate at 60 to 150 ° C. for 1 to 5 minutes, preferably at 80 to 140 ° C. for 1 to 3 minutes, and then fired (Post Expoure Bake (PEB)). Further, 0.1 to 5% by mass, preferably 2 to 3% by mass of an aqueous solution of an alkali aqueous solution such as tetramethylammonium hydroxide (TMAH) is used for 0.1 to 3 minutes, preferably 0.5 to 2 minutes It develops by conventional methods, such as the dip method, the puddle method, and the spray method, and the target pattern is formed on a board | substrate.

In addition, the unexposed portion is dissolved by developing using a developing solution of an organic solvent for 0.1 to 3 minutes, preferably 0.5 to 2 minutes by conventional methods such as the dip method, the puddle method, and the spray method. It is also possible to form negative patterns that become. As a developing solution at this time, 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, Ketones of acetophenone and methyl acetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate, isoamyl acetate, phenyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, and isoformate Mill, methyl valeric acid, methyl pentenate, methyl crotonate, ester of ethyl crotonate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenyl acetate, benzyl formate, phenyl ethyl formate, methyl 3-phenylpropionate, Aromatic esters of benzyl propionate, ethyl phenyl acetate and 2-phenylethyl acetate can be preferably used.

In addition, the resist material of the present invention can reduce the pattern size after development by various shrinking methods. For example, the hole size can be shrunk by known methods such as thermal flow, RELACS, SAFIRE, WASOOM. In particular, when the hydrogenated ROMP polymer (cycloolefin ring-opening metathesis polymer hydrogenated substance) or the like having a low polymer Tg is blended, the hole size can be effectively reduced by the thermal flow.

In addition, the chemically amplified resist material of the present invention is particularly suitable for fine patterning by 250-190 nm deep ultraviolet rays or excimer lasers, X-rays and electron beams, even among high energy rays. Moreover, since the target pattern can be obtained as it is in the said range, it is preferable.

In addition, exposure can also use an immersion method in addition to a normal exposure method. In immersion lithography, an immersion medium (preferably water) is inserted between the resist film and the projection lens (preferably between the substrate and the projection lens) after prebaking and exposed. In ArF immersion lithography, pure water is mainly used as the immersion medium. Combination with projection lenses with NA greater than 1.0 is an important technique for extending ArF lithography to 65 nm nodes and beyond, and development is accelerating. In this case, it is also possible to use a protective film insoluble in water.

The above-mentioned protective film insoluble in water is used to prevent the eluate from the resist film and to increase the water slidability of the film surface. One type is the organic solvent peeling type which requires peeling before alkali development by the organic solvent which does not melt a resist film, and the other type is an alkali soluble type which is soluble in an alkaline developing solution and removes a protective film with removal of a resist film soluble part.

The latter is based on a high molecular compound having a 1,1,1,3,3,3-hexafluoro-2-propanol moiety, which is particularly insoluble in water and soluble in an alkaline developer, and is an alcoholic solvent having 4 or more carbon atoms, 8 carbon atoms. Preferred are materials dissolved in an ether solvent of 12 to 12 and a mixed solvent thereof.

It can also be set as the material which melt | dissolved the surfactant insoluble in water mentioned above and soluble in alkaline developing solution in the C4 or more alcohol solvent, the C8-C12 ether solvent, or these mixed solvents.

In addition, as a means of the pattern formation method, pure water rinsing (postsoaking) may be performed after the photoresist film is formed to extract an acid generator or the like from the surface of the film, or to wash away the particles. Rinsing (postsoaking) may be performed to remove this.

[Example]

Hereinafter, although a synthesis example, a comparative synthesis example, an Example, and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to a following example. In addition, Me represents a methyl group in the following example.

Synthesis Example 1 Synthesis of Polymer-1

4.94 g of triphenylsulfonium = 2- (6-methacryloyloxy-2-oxohexahydro-3,5-methano-2H-cyclopenta [b] furan-7-car in a flask with nitrogen atmosphere Bonyloxy) ethanesulfonate, 19.0 g methacrylic acid = 1-isopropylcyclopentyl, 6.61 g methacrylic acid = 2-oxotetrahydrofuran-3-yl, 12.09 g methacrylic acid = 5-oxo4 0.45 g of, 8-dioxatricyclo [4.2.1.0 ^3,7 ] non-2-yl, 2.20 g of V-601 (manufactured by Wako Pure Chemical), 2-mercaptoethanol and 68 g of GBL (gammabutyro) Lactone) to prepare a monomer-polymerization initiator solution. 24 g of GBL was taken to another flask made into nitrogen atmosphere, heated to 80 degreeC, stirring, and the said monomer solution was dripped over 4 hours. After completion of dropping, stirring was continued for 2 hours while maintaining the temperature of the polymerization liquid at 80 ° C, and then cooled to room temperature. The obtained polymer liquid was dripped at 640 g of water-methanol solutions (weight ratio 3: 7) stirred vigorously, and the precipitated copolymer was separated by filtration. The copolymer was washed twice with 240 g of water-methanol solution (weight ratio 3: 7), and then vacuum dried at 50 ° C. for 20 hours to obtain 30.3 g of a white powdery copolymer. When the copolymer was analyzed by ¹³ C-NMR, the copolymer composition ratio was 2/50/20/28 mol% in the order of the monomers described above.

(Synthesis Examples 2 to 7, Comparative Synthesis Examples 1 to 4) Synthesis of Polymer-2 to Polymer-7 and Polymers A to D

Except having changed the kind and compounding ratio of each monomer, the high molecular compound shown below was manufactured by the same procedure as the said synthesis example 1.

Preparation of Chemically Amplified Resist Materials (Examples 1-1 to 1-7, Comparative Examples 1-1 to 1-4)

0.01 mass% of the following surfactant A (manufactured by Ohm Nova) was prepared using the polymer compound shown in the above Synthesis Example and having the following photoacid generator, quencher and alkali-soluble surfactant (SF-1) as shown in Table 1 below. The resist solutions (R-01 to R11) were each prepared by dissolving in a containing solvent to combine resist materials and filtering the resist material with a 0.2 micrometer Teflon (trademark) filter.

In Table 1, the photoacid generator, the quencher, the solvent, and the alkali-soluble surfactant (SF-1) used as the resist material together with the polymer compound shown in the above synthesis example are as follows.

P-1 to P-7: polymer-1 to polymer-7

P-A to P-D: the above polymer-A to polymer-D

PAG-1: 4-t-butylphenyldiphenylsulfonium = 2- (adamantane-1-carbonyloxy) -1,1,3,3,3-pentafluoropropane-1-sulfonate

PAG-2: N-nonafluorobutanesulfonyloxy-1,8-naphthalenedicarboxyimide

Q-1: 1-benzyloxycarbonyl-2-phenylbenzimidazole

Q-2: triphenylsulfonium = 10-camphorsulfonate

PGMEA: propylene glycol monomethyl ether acetate

GBL:? -Butyrolactone

Alkali-soluble surfactant (SF-1): the following chemical formula (compound described in Japanese Patent Laid-Open No. 2008-122932)

Surfactant A:

3-methyl-3- (2,2,2-trifluoroethoxymethyl) oxetane, tetrahydrofuran, 2,2-dimethyl-1,3-propanediol copolymer (manufactured by Ohmova) )

ArF  Exposure Patterning  evaluation( Example  2-1 to Example  2-7, Comparative example  2-1 to Comparative example  2-4)

Spin coating a resist solution on an antireflection film (100 nm film thickness) substrate prepared by applying an antireflection film solution (Nissan Chemical Industries, Ltd., ARC-29A) on a silicon substrate and baking at 200 ° C. for 60 seconds. Then, it baked for 60 second at 100 degreeC using the hotplate, and the resist film of 120 nm film thickness was produced. This was immersed and exposed to light using an ArF excimer laser scanner (Nikon Corporation, NSR-S610C, NA = 1.30, bipolar, Cr mask), and baked (PEB) at 80 ° C. for 60 seconds to give 2.38 mass% of tetra The development was performed for 60 seconds with an aqueous solution of methylammonium hydroxide.

Evaluation of the resist shape made the exposure amount which resolves the line and space of a 40 nm group 1: 1 to the optimal exposure amount (Eop, mJ / cm <^2> ). The pattern shape and roughness (LWR) at the said optimal exposure amount were observed and evaluated by the electron microscope.

The evaluation criteria of the pattern shape were as follows.

Rectangular: Line sidewalls are vertical, with small dimensional changes from bottom (near substrate) to top and good.

Taper: A shape in which the line dimension decreases from the bottom to the top.

Evaluation of the amount of the resist component dissolved into the immersion water was first placed on a 10 cm inner diameter Teflon (registered trademark) ring on the wafer on which the resist film was formed by the above method, and carefully poured 10 ml of pure water thereinto room temperature. The resist film was contacted with pure water for 60 seconds at. Then, pure water was collect | recovered and the anion component concentration (mol / cm <^2> second) of the sulfonium salt in pure water was measured by the LC-MS analyzer (made by Agilent Technologies).

About the adhesiveness to the board | substrate of a resist pattern, it observed with the electron microscope and evaluated the presence or absence of a peeling defect.

Table 2 shows the evaluation results of each resist material.

From the results in Table 2, when the polymer compound having the sulfonium salt of the specific structure of the present invention in the repeating unit is used as the base resin of the resist material, the rectangularity of the pattern is excellent, the elution of the anion component of the sulfonium salt is low, and the LWR Was small and it was confirmed that the adhesiveness to the board | substrate of a pattern was also favorable. In view of the above, the resist material of the present invention is preferable as an immersion lithography material.

The present invention is not limited to the above embodiments. The said embodiment is an illustration, Any thing which has a structure substantially the same as the technical idea described in the claim of this invention, and exhibits the same effect is contained in the technical scope of this invention.

Claims (5)

A polymer compound containing a repeating unit represented by the following formula (1).
&Lt; Formula 1 >

(Wherein R ¹ represents any ^one of a hydrogen atom, a fluorine atom, a methyl group and a trifluoromethyl group, and R ² , R ³ and R ⁴ each independently represent a substituted or unsubstituted straight chain having 1 to 10 carbon atoms, Any of branched or cyclic alkyl, alkenyl and oxoalkyl groups, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, an aralkyl group and an aryloxoalkyl group, or R ² , R ³ and Any two or more of R ⁴ may be bonded to each other to form a ring together with a sulfur atom in the formula, X ¹ represents O or CH ₂ , and A ¹ is linear, branched or cyclic having 1 to 10 carbon atoms. Represents a divalent hydrocarbon group, B ¹ represents an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 18 carbon atoms, which may include a hetero atom other than fluorine, and k ¹ represents an integer of 0 or 1) The polymer compound according to claim 1, further comprising a repeating unit having an acid labile group in addition to the repeating unit represented by the formula (1). The chemically amplified resist material containing (A) the high molecular compound of Claim 1 or 2, (B) organic solvent, (C) photoacid generator, and (D) basic compound. A step of applying the chemically amplified resist material according to claim 3 on a substrate, a step of exposing with a high energy ray through a photomask after heat treatment, and a step of developing using a developer. Way. A process of applying the chemically amplified resist material according to claim 3 on a substrate, a process of applying a protective film insoluble in water and soluble in an alkaline developer after heat treatment, and inserting water between the substrate and the projection lens to insert a photomask. And a step of developing using a developing solution and exposing with high energy rays.