JP5537859B2 - Treatment liquid for pattern formation by chemically amplified resist composition and resist pattern formation method using the same - Google Patents

Description

  The present invention relates to a processing solution for pattern formation using a chemically amplified resist composition suitable for semiconductor manufacturing processes such as ICs, circuit boards such as liquid crystals and thermal heads, and other photofabrication lithography processes, and the like. The present invention relates to a resist pattern forming method using In particular, a treatment liquid for pattern formation using a chemically amplified resist composition suitable for exposure in an ArF exposure apparatus and immersion projection exposure apparatus using far ultraviolet light having a wavelength of 300 nm or less as a light source, and a resist pattern using the treatment liquid The present invention relates to a forming method.

  Since the resist for KrF excimer laser (248 nm), a chemical amplification type image forming method has been used as an image forming method in order to compensate for sensitivity reduction due to light absorption. An example of a positive-type chemical amplification image forming method will be described. When exposed, the acid generator in the exposed area decomposes to generate an acid, and the acid generated in the exposure bake (PEB) is a reaction catalyst. Is used to change an alkali-insoluble group to an alkali-soluble group, and an exposed portion is removed by alkali development.

  With the miniaturization of semiconductor elements, the wavelength of an exposure light source has been shortened and the projection lens has a high numerical aperture (high NA). Currently, an exposure machine using an ArF excimer laser having a 193 nm wavelength as a light source has been developed. In addition, so-called immersion methods, in which a high refractive index liquid (hereinafter also referred to as “immersion liquid”) is filled between the projection lens and the sample, are being actively studied. The liquid immersion method can be combined with super-resolution techniques such as the phase shift method and the modified illumination method that are currently being studied.

  Further, as a technique for further increasing the resolution, a double exposure technology and a double patterning technology have been proposed.

Conventionally, pattern formation of electronic devices such as semiconductor elements is performed by reducing and transferring a mask or reticle pattern, which is 4-5 times the size of the pattern to be formed, to an object to be exposed such as a wafer using a reduction projection exposure apparatus. It was.
However, with the miniaturization of dimensions, the conventional exposure method has a problem in that the light irradiated to adjacent patterns interferes with each other and the optical contrast is reduced. The design is divided into two or more, each mask is exposed independently, and an image is synthesized. In these double exposure methods, it is necessary to divide the design of the exposure mask, synthesize the image again on the object to be exposed (wafer), and the pattern on the reticle faithfully adheres to the object to be exposed. It is necessary to devise the division of the mask design so that it can be reproduced.
An example in which the effect of these double exposure methods is studied for transferring a fine image pattern of a semiconductor element is introduced in Patent Document 1 and the like.

  However, when the conventional resist composition is simply applied to the double exposure method, it is necessary to perform pattern formation near the resolution limit, so that a sufficient exposure margin and depth of focus cannot be obtained. become.

  On the other hand, Patent Documents 2 and 3 describe a double development technique as a double patterning technique for increasing resolution. In this example, a general chemical amplification type image forming method is used, and the polarity of the resin in the resist composition by exposure becomes high polarity in a region with high light intensity and low polarity in a region with low light intensity. By taking advantage of this, a high exposure area of a specific resist film is dissolved in a high polarity developer (more specifically, a conventional alkaline solution) (positive development), and a low exposure area is developed with a low polarity. It is dissolved in a liquid (specifically, a developer containing an organic solvent) (organic solvent development). Specifically, as shown in FIG. 1, the region of the irradiation light 1 with the exposure amount E2 or more is dissolved using an alkaline aqueous solution, and the region of the exposure amount E1 or less is dissolved with a developer containing an organic solvent. ing. As a result, as shown in FIG. 1, an intermediate exposure amount (E2-E1) region remains without being developed, and an L / S pattern 3 having a half pitch of the exposure mask 2 is formed on the wafer 4. Yes.

  However, conventionally, when forming a resist pattern using a developer containing an organic solvent, in order to stably form a high-precision fine pattern for manufacturing a highly integrated and high-precision electronic device, Further improvements have been sought for in-plane uniformity (CDU) and defect performance of resist patterns.

JP 2006-156422 A JP 2000-199953 A JP 2008-292975 A

  In order to solve the above-mentioned problems and to stably form a high-precision fine pattern for manufacturing a highly integrated and high-precision electronic device, the present invention provides an in-plane uniform resist pattern while containing an organic solvent. An object of the present invention is to provide a pattern forming treatment liquid using a chemically amplified resist composition that has excellent properties (CDU) and defect performance and can reduce the amount of the treatment liquid used, and a pattern forming method using the same.

When developing with an organic solvent-based developer, the dissolution rate is slower than that with a water-based alkaline developer. Specifically, the maximum dissolution rate of the aqueous alkaline developer (the rate at which the film thickness decreases when the resist composition is immersed in the developer under general development conditions) generally exceeds 1000 nm / sec, The maximum dissolution rate of development with an organic solvent developer is generally about 20 nm / sec.
The inventors of the present application estimated that such a slow dissolution rate deteriorates wafer in-plane line width uniformity and defect performance. In other words, there is a difference in the pour time of the processing liquid for the in-plane uniformity deterioration, and for the defect performance deterioration, a lot of resist components with insufficient solubility are generated in the exposed portion where the exposure amount is insufficient, Each of them was estimated to have an influence, and the configuration of the present invention was reached.
The present invention has the following configuration, whereby the above object of the present invention is achieved.
[1]
A processing solution for pattern formation by a chemically amplified resist composition, comprising a surfactant and an organic solvent, wherein the processing solution is a developer or a rinsing solution, and the water content of the processing solution is A processing liquid for pattern formation, which is less than 10% by mass.
[2]
The processing solution for pattern formation using the chemically amplified resist composition according to [1], which is a developer.
[3]
The processing solution for pattern formation using the chemically amplified resist composition according to [2], wherein the developer contains an ester solvent.
[4]
The processing solution for pattern formation using the chemically amplified resist composition according to [2] or [3], wherein the developer contains butyl acetate.
[5]
A pattern forming treatment solution using the chemically amplified resist composition according to [1], which is a rinse solution.
[6]
The rinsing liquid contains an alcohol-based solvent, The pattern forming treatment liquid using the chemically amplified resist composition according to [5].
[7]
The rinsing solution contains 4-methyl-2-pentanol, [5] or [6] The pattern forming treatment solution using the chemically amplified resist composition according to [6].
[8]
A pattern forming method comprising a step of forming a resist film using a chemically amplified resist composition, exposing, and developing using a developer containing a surfactant and an organic solvent, The pattern forming method, wherein the water content of the developer is less than 10% by mass.
[9]
The pattern forming method as described in [8], wherein the developer contains an ester solvent.
[10]
The pattern forming method according to [8] or [9], wherein the developer contains butyl acetate.
[11]
A pattern comprising a step of forming a resist film using a chemically amplified resist composition, exposing, developing using a developer, and rinsing with a rinsing solution containing a surfactant and an organic solvent. It is a formation method, Comprising: The moisture content of the said rinse liquid is less than 10 mass%, The pattern formation method characterized by the above-mentioned.
[12]
The pattern forming method according to [11], wherein the rinse liquid contains an alcohol solvent.
[13]
The pattern forming method as described in [11] or [12], wherein the rinse liquid contains 4-methyl-2-pentanol.
The present invention relates to the above [1] to [13], but other matters are also described below.

1.
A processing solution for pattern formation using a chemically amplified resist composition, comprising a surfactant and an organic solvent.
2.
2. A pattern forming treatment solution using the chemically amplified resist composition according to 1 above, which is a developer.
3.
2. A pattern forming treatment solution using the chemically amplified resist composition according to the above item 1, which is a rinse solution.
4).
A pattern forming method comprising: forming a resist film using a chemically amplified resist composition, exposing the resist film, and developing using a developer containing a surfactant and an organic solvent.
5.
A pattern comprising a step of forming a resist film using a chemically amplified resist composition, exposing, developing using a developer, and rinsing with a rinsing solution containing a surfactant and an organic solvent. Forming method.

The preferred embodiments of the present invention will be further described below.
6).
3. The pattern forming treatment solution using the chemically amplified resist composition according to 2 above, wherein the organic solvent is an ester solvent.
7).
The rinsing liquid for pattern formation using the chemically amplified resist composition according to the above item 3, wherein the organic solvent is an alcohol solvent.
8).
6. The method of forming a resist pattern as described in 4 or 5 above, further comprising a step of developing using an aqueous alkaline developer.

INDUSTRIAL APPLICABILITY According to the present invention, a processing liquid for pattern formation using a chemically amplified resist composition that is excellent in in-plane uniformity (CDU) and defect performance of a resist pattern and can reduce the amount of processing liquid used, and a pattern forming method using the same Can be provided.
The treatment liquid of the present invention contains an organic solvent and a surfactant, and improves the in-wafer in-plane line width uniformity and defect performance. It is presumed that this is because the surfactant contributes to promoting the penetration of the developer or rinse solution into the resist composition and improving the dissolution rate.
Furthermore, when a treatment liquid containing a surfactant is used, sufficient solubility can be compensated even with a small amount of the treatment liquid. As a result, it is estimated that good in-plane line width uniformity and good defect performance can be obtained.

It is a schematic diagram which shows the pattern formation method which used together conventional image development (positive image development) and image development using an organic solvent.

Hereinafter, modes for carrying out the present invention will be described.
In addition, in the description of the group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes the thing which has a substituent with the thing which does not have a substituent. . For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
“Actinic light” or “radiation” in the present specification means, for example, an emission line spectrum of a mercury lamp, far ultraviolet rays represented by an excimer laser, extreme ultraviolet rays (EUV light), X-rays, electron beams and the like. In the present invention, light means actinic rays or radiation.
In addition, the term “exposure” in the present specification is not limited to exposure with far ultraviolet rays such as mercury lamps and excimer lasers, X-rays, EUV light, etc., but also particle beams such as electron beams and ion beams, unless otherwise specified. Include drawing in exposure.

Surfactant The processing liquid for pattern formation by the chemically amplified resist composition of the present invention contains a surfactant. Surfactant is either fluorine-based and / or silicon-based surfactant (fluorine-based surfactant and silicon-based surfactant, surfactant containing both fluorine atom and silicon atom), or two or more thereof It is more preferable to contain.

  Examples of these fluorine and / or silicon surfactants include, for example, JP-A No. 62-36663, JP-A No. 61-226746, JP-A No. 61-226745, JP-A No. 62-170950, JP 63-34540 A, JP 7-230165 A, JP 8-62834 A, JP 9-54432 A, JP 9-5988 A, JP 2002-277862 A, US Patent Nos. 5,405,720, 5,360,692, 5,529,881, 5,296,330, 5,436,098, 5,576,143, 5,294,511, 5,824,451 Surfactant can be mentioned, The following commercially available surfactant can also be used as it is.

  Examples of commercially available surfactants that can be used include EFTOP EF301 and EF303 (manufactured by Shin-Akita Kasei Co., Ltd.), Florard FC430, 431 and 4430 (manufactured by Sumitomo 3M Co., Ltd.), MegaFuck F171, F173, F176 and F189. , F113, F110, F177, F120, R08 (manufactured by Dainippon Ink & Chemicals, Inc.), Surflon S-382, SC101, 102, 103, 104, 105, 106 (manufactured by Asahi Glass Co., Ltd.), Troisol S-366 (Manufactured by Troy Chemical Co., Ltd.), GF-300, GF-150 (manufactured by Toa Gosei Chemical Co., Ltd.), Surflon S-393 (manufactured by Seimi Chemical Co., Ltd.), F-top EF121, EF122A, EF122B, RF122C, EF125M , EF135M, EF351, 352, EF801, EF802, EF 01 (manufactured by Gemco), PF636, PF656, PF6320, PF6520 (manufactured by OMNOVA), FTX-204D, 208G, 218G, 230G, 204D, 208D, 212D, 218, 222D (manufactured by Neos) Fluorine type surfactant or silicon type surfactant can be mentioned. Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

  In addition to the known surfactants described above, surfactants are derived from fluoroaliphatic compounds produced by the telomerization method (also referred to as the telomer method) or the oligomerization method (also referred to as the oligomer method). A surfactant using a polymer having a fluoroaliphatic group can be used. The fluoroaliphatic compound can be synthesized by the method described in JP-A-2002-90991.

  As the polymer having a fluoroaliphatic group, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate and / or (poly (oxyalkylene)) methacrylate is preferable and distributed irregularly. It may be block copolymerized. Examples of the poly (oxyalkylene) group include a poly (oxyethylene) group, a poly (oxypropylene) group, a poly (oxybutylene) group, and the like, and a poly (oxyethylene, oxypropylene, and oxyethylene group). A unit having different chain lengths in the same chain length, such as a block link) or poly (block link of oxyethylene and oxypropylene) may be used. Furthermore, a copolymer of a monomer having a fluoroaliphatic group and (poly (oxyalkylene)) acrylate (or methacrylate) is not only a binary copolymer but also a monomer having two or more different fluoroaliphatic groups, Further, it may be a ternary or higher copolymer obtained by simultaneously copolymerizing two or more different (poly (oxyalkylene)) acrylates (or methacrylates).

Examples of commercially available surfactants include Megafac F178, F-470, F-473, F-475, F-476, and F-472 (Dainippon Ink Chemical Co., Ltd.). Further, a copolymer of an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxyalkylene)) acrylate (or methacrylate), an acrylate (or methacrylate) having a C ₆ F ₁₃ group and (poly (oxy) (Ethylene)) acrylate (or methacrylate) and (poly (oxypropylene)) acrylate (or methacrylate) copolymer, acrylate (or methacrylate) and (poly (oxyalkylene)) acrylate having C ₈ F ₁₇ groups (or Copolymer of acrylate (or methacrylate), (poly (oxyethylene)) acrylate (or methacrylate), and (poly (oxypropylene)) acrylate (or methacrylate) having a C ₈ F ₁₇ group Coalesce, etc. It can be.

  In the present invention, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, etc. Sorbitans such as polyoxyethylene alkyl allyl ethers, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, sorbitan tristearate Fatty acid esters, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopal Te - DOO, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, may be mentioned polyoxyethylene sorbitan tristearate nonionic surfactants of polyoxyethylene sorbitan fatty acid esters such as such.

  Surfactants may be used alone or in several combinations.

  The content of the surfactant is preferably 0.0001 to 10% by mass, more preferably 0.001 to 5% by mass, based on the total amount of the processing liquid for pattern formation using the chemically amplified resist composition.

The processing solution for pattern formation using the chemically amplified resist composition of the present invention is preferably a developer or a rinsing solution.
The organic solvent contained in the treatment liquid of the present invention is not particularly limited as long as it dissolves the resin (A ′), and those used as a coating solvent for a resist composition can be used. . Specifically, an organic solvent as a developer or an organic solvent as a rinse liquid described below is preferable.

The processing solution for pattern formation using the chemically amplified resist composition of the present invention is preferably a developer or a rinsing solution used in the development step or the rinsing step of the chemically amplified resist composition.
When the processing solution is a developing solution, those that function with the developing solution, preferably those that can dissolve the resist composition with low exposure intensity, and those that are difficult to dissolve the resist composition with high exposure intensity, more specifically, What can melt | dissolve the area | region below the exposure amount E1 in FIG. 1 is preferable.
When the processing solution is a rinsing solution, it is preferable that the resist composition is not dissolved but the development residue after the development processing can be washed away.

Organic solvent-based developer As the organic solvent of the pattern-forming developer using a chemically amplified resist composition containing a surfactant and an organic solvent, any solvent that dissolves a portion of the resist pattern in the unexposed area can be used. There is no limitation, and general organic solvents can be used. Preferably, polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents and hydrocarbon solvents are used. More preferably, it is an ester solvent.

Examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, and methyl ethyl ketone. Methyl isobutyl ketone, acetyl acetone, acetonyl acetone, ionone, diacetyl alcohol, acetyl carbinol, acetophenone, methyl naphthyl ketone, isophorone, propylene carbonate, and the like.
Examples of the ester solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3- Examples include ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, and propyl lactate. In particular, alkyl acetates such as methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, and amyl acetate are preferred.
Examples of the alcohol solvent include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, 4-methyl-2- Alcohols such as pentanol, n-heptyl alcohol, n-octyl alcohol and n-decanol; glycol solvents such as ethylene glycol, diethylene glycol and triethylene glycol; ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl Ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether, triethylene glycol monoethyl Ether, may be mentioned glycol monoethyl ether and methoxymethyl butanol.
Examples of the ether solvent include dioxane, tetrahydrofuran and the like in addition to the glycol ether solvent.
Examples of the amide solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolidinone and the like. Can be used.
Examples of the hydrocarbon solvent include aromatic hydrocarbon solvents such as toluene and xylene, and aliphatic hydrocarbon solvents such as pentane, hexane, octane and decane.

  As an organic solvent, what has a structure represented by following General formula (1) is more preferable, and what has a structure represented by General formula (2) is still more preferable.

In general formula (1),
R and R ′ each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group or a halogen atom. R and R ′ may be bonded to each other to form a ring.

In general formula (2),
R ″ and R ″ ″ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group, or a halogen atom. R ″ and R ″ ″ may be bonded to each other to form a ring.
R ′ ″ represents an alkylene group or a cycloalkylene group.

  The number of carbon atoms of each group in R to R "'" is not particularly limited, but is preferably 1 to 10, and more preferably 1 to 8.

A plurality of the above solvents may be mixed, and it is preferable to use an ester solvent and a ketone solvent in combination.
In addition, the organic solvent may be used by mixing with a solvent other than the above or water within the range having performance. However, in order to fully exhibit the effects of the present invention, the water content of the developer as a whole is preferably less than 10% by mass, and more preferably substantially free of moisture.
That is, the amount of the organic solvent used with respect to the developer is preferably 90% by mass or more and 99.9999% by mass or less, and 95% by mass or more with respect to the total amount of the developer (total amount of the developer including the surfactant). More preferably, it is 99.999 mass% or less.

The vapor pressure of the developer containing the organic solvent is preferably 5 kPa or less, more preferably 3 kPa or less, and particularly preferably 2 kPa or less at 20 ° C. By setting the vapor pressure of the developing solution to 5 kPa or less, evaporation of the developing solution on the substrate or in the developing cup is suppressed, temperature uniformity in the wafer surface is improved, and as a result, dimensional uniformity in the wafer surface is improved. It improves.
Specific examples having a vapor pressure of 5 kPa or less include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, 4-heptanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl Ketone solvents such as isobutyl ketone, butyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxy Esters such as butyl acetate, 3-methyl-3-methoxybutyl acetate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate Agent, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, 4-methyl-2-pentanol, n-heptyl alcohol, n-octyl alcohol Alcohol solvents such as n-decanol, glycol solvents such as ethylene glycol, diethylene glycol and triethylene glycol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether Glycol ether solvents such as triethylene glycol monoethyl ether and methoxymethylbutanol , Ether solvents such as tetrahydrofuran, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, amide solvents of N, N-dimethylformamide, aromatic hydrocarbon solvents such as toluene and xylene, octane, decane, etc. And aliphatic hydrocarbon solvents.
Specific examples having a vapor pressure of 2 kPa or less, which is a particularly preferable range, include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, 4-heptanone, 2-hexanone, diisobutyl ketone, cyclohexanone, and methylcyclohexanone. , Ketone solvents such as phenylacetone, butyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3- Ester solvents such as methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, ethyl lactate, butyl lactate and propyl lactate, n-butyl alcohol, ec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol, n-hexyl alcohol, 4-methyl-2-pentanol, n-heptyl alcohol, n-octyl alcohol, alcohol solvents such as n-decanol, ethylene glycol, diethylene glycol, Glycol solvents such as triethylene glycol, and glycol ethers such as ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, diethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and methoxymethylbutanol Solvents, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethyl Formamide amide solvents, aromatic hydrocarbon solvents such as xylene, octane, aliphatic hydrocarbon solvents decane.

Organic solvent-based rinsing liquid The organic solvent of the rinsing liquid for pattern formation by the chemically amplified resist composition containing a surfactant and an organic solvent is not particularly limited as long as the resist pattern in the exposed area is not dissolved. Organic solvents can be used. As the organic solvent for the rinse liquid, an organic solvent selected from hydrocarbon solvents, ketone solvents, ester solvents, alcohol solvents, amide solvents and ether solvents is preferably used. More preferable examples include a rinsing liquid containing an organic solvent selected from a ketone solvent, an ester solvent, an alcohol solvent, and an amide solvent. More preferably, it is a rinsing liquid containing an alcohol solvent or an ester solvent, and more preferably an rinsing liquid containing an alcohol solvent, for example, a monohydric alcohol. Particularly preferable examples include a rinsing liquid containing a monohydric alcohol having 5 or more carbon atoms. Here, examples of the monohydric alcohol include linear, branched, and cyclic monohydric alcohols, and specifically, 1-butanol, 2-butanol, 3-methyl-1-butanol, and tert-butyl alcohol. 1-pentanol, 2-pentanol, 1-hexanol, 4-methyl-2-pentanol, 1-heptanol, 1-octanol, 2-hexanol, cyclopentanol, 2-heptanol, 2-octanol, 3-hexanol , 3-heptanol, 3-octanol, 4-octanol and the like, and particularly preferable monohydric alcohols having 5 or more carbon atoms include 1-hexanol, 2-hexanol, 4-methyl-2-pentanol, 1- Pentanol, 3-methyl-1-butanol and the like can be used.

  A plurality of these components may be mixed, and it is preferable to use an alcohol solvent and an ether solvent in combination. Moreover, you may mix and use with organic solvents other than the above.

The water content in the rinsing liquid for pattern formation by the chemically amplified resist composition is preferably less than 10% by mass, more preferably less than 5% by mass, and particularly preferably less than 3% by mass. By setting the water content to less than 10% by mass, good development characteristics can be obtained.
That is, the amount of the organic solvent used relative to the rinsing liquid for pattern formation by the chemically amplified resist composition is 90% by mass or more and 99.9999% by mass with respect to the total amount of the rinsing liquid (total amount of the rinsing liquid including the surfactant). Or less, more preferably 95% by mass or more and 99.999% by mass or less, and most preferably 97% by mass or more and 99.999% by mass or less.

  The vapor pressure of the rinsing liquid for pattern formation with the chemically amplified resist composition used after development with a developer containing an organic solvent is preferably 0.05 kPa or more and 5 kPa or less, and 0.1 kPa or more and 5 kPa at 20 ° C. The following is more preferable, and 0.12 kPa or more and 3 kPa or less is most preferable. By setting the vapor pressure of the rinse liquid to 0.05 kPa or more and 5 kPa or less, the temperature uniformity in the wafer surface is improved, and further, the swelling due to the penetration of the rinse solution is suppressed, and the dimensional uniformity in the wafer surface. Improves.

<Resist pattern formation method>
The resist pattern forming method of the present invention preferably includes a step of forming a film using the chemically amplified resist composition, a step of exposing the film, and a step of developing using a developer in this order. It is preferable to further include a step of rinsing with a rinsing liquid after development.
In the pattern forming method of the present invention, the developing step is a step of using a developer containing the surfactant and an organic solvent, or further includes a rinsing step, wherein the interface is used as a rinsing solution. It includes a step of using a rinsing solution having an activator and an organic solvent, or both.
It is also preferable to include a preheating step (PB; Prebake) after the film formation and before the exposure step.
It is also preferable to include a post-exposure heating step (PEB; Post Exposure Bake) after the exposure step and before the development step.
The heating temperature is preferably 70 to 120 ° C for both PB and PEB, more preferably 100 to 120 ° C.
The heating time is preferably 30 to 300 seconds, more preferably 30 to 180 seconds, and still more preferably 30 to 90 seconds.
Heating can be performed by means provided in a normal exposure / developing machine, and may be performed using a hot plate or the like.
The reaction of the exposed part is promoted by baking, and the sensitivity and pattern profile are improved.

As a developing method, for example, a method in which a substrate is immersed in a tank filled with a developer for a certain period of time (dip method), a method in which the developer is raised on the surface of the substrate by surface tension and is left stationary for a certain time (paddle) Method), a method of spraying the developer on the substrate surface (spray method), a method of continuously discharging the developer while scanning the developer discharge nozzle on the substrate rotating at a constant speed (dynamic dispensing method) Etc. can be applied.
When the various development methods described above include a step of discharging the developer from the developing nozzle of the developing device toward the resist film, the discharge pressure of the discharged developer (the flow rate per unit area of the discharged developer) is Preferably it is 2 mL / sec / mm ² or less, More preferably, it is 1.5 mL / sec / mm ² or less, More preferably, it is 1 mL / sec / mm ² or less. There is no particular lower limit on the flow rate, but 0.2 mL / sec / mm ² or more is preferable in consideration of throughput.
Moreover, when the process is included, the flow rate of the rinse liquid is preferably ² mL / sec / mm ² or less. Although there is no particular lower limit, 0.05 mL / sec / mm ² or more is preferable in consideration of the rinse liquid discharge stability.
By setting the discharge pressure of the discharged developer to be in the above range, pattern defects derived from the resist residue after development can be remarkably reduced.
The details of this mechanism are not clear, but perhaps by setting the discharge pressure within the above range, the pressure applied by the developer to the resist film will decrease, and the resist film / resist pattern may be inadvertently cut or collapsed. This is considered to be suppressed.
The developer discharge pressure (mL / sec / mm ² ) is a value at the developing nozzle outlet in the developing device.

  Examples of the method for adjusting the discharge pressure of the developer include a method for adjusting the discharge pressure with a pump and the like, and a method for changing the pressure by adjusting the pressure by supplying from a pressurized tank.

  Moreover, you may implement the process of stopping image development, after the process of developing, substituting with another solvent.

  In the rinsing step, the developed wafer is rinsed (cleaned) using a rinsing liquid containing a surfactant and an organic solvent. The method of rinsing is not particularly limited. For example, a method of continuously discharging a rinsing liquid onto a substrate rotating at a constant speed (rotary coating method), and a method of immersing the substrate in a bath filled with the rinsing liquid for a certain period of time (Dip method), a method of spraying a rinsing liquid on the substrate surface (spray method), etc. can be applied, and among these, a cleaning treatment is performed by a spin coating method, and the substrate is rotated at a rotational speed of 1000 rpm to 4000 rpm after cleaning. It is preferable to remove the rinse liquid from the substrate.

In the method of the present invention, the development system can be applied to either dynamic development without forming a paddle, stationary development to form a paddle, or development system that swings while forming a paddle.
In the dynamic development, an organic solvent-based developer is discharged from the developing nozzle while rotating the wafer, and immediately after the discharge of the organic solvent-based developer, the rinse nozzle is discharged by switching to the rinse nozzle.
The discharge time of the organic solvent developer is preferably 2 to 100 seconds, and more preferably 5 to 60 seconds.
In the case of a general 8 to 12 inch wafer, the total discharge amount of the organic solvent developer is preferably 3 to 50 ml, and more preferably 5 to 15 ml.
The rotation speed of the wafer is preferably 50 to 2000 rpm and more preferably 100 to 1800 rpm for a general 8 to 12 inch wafer.
The discharge time of the rinsing liquid is preferably 2 to 100 seconds, and more preferably 5 to 60 seconds.
The rotation speed of the wafer is preferably 50 to 2000 rpm and more preferably 100 to 1800 rpm for a general 8 to 12 inch wafer.
In paddle formation and stationary development, the organic solvent developer is discharged from the developing nozzle while rotating the wafer to form a paddle, and after leaving the wafer to stand for a predetermined time, the wafer is rotated and the rinsing liquid is discharged from the rinse nozzle. Discharge. The rotation of the wafer and the discharge of the rinsing liquid may be performed simultaneously.
The discharge time of the organic solvent-based developer is preferably 2 to 30 seconds, and more preferably 5 to 20 seconds.
In the case of a general 8 to 12 inch wafer, the total discharge amount of the organic solvent developer is preferably 3 to 50 ml, and more preferably 5 to 15 ml.
The rotation speed of the wafer is preferably 5 to 500 rpm and more preferably 5 to 250 rpm in the case of a general 8 to 12 inch wafer.
The standing time of the wafer is preferably 2 to 100 seconds, and more preferably 5 to 60 seconds.
The discharge time of the rinsing liquid is preferably 2 to 100 seconds, and more preferably 5 to 60 seconds.
The rotation speed of the wafer is preferably 50 to 2000 rpm and more preferably 100 to 1800 rpm for a general 8 to 12 inch wafer.
In paddle formation / oscillation development, an organic solvent-based developer is discharged from the developing nozzle while rotating the wafer to form a paddle, and the wafer is rotated slightly for a predetermined time and then rotated. The rinse liquid is discharged from the rinse nozzle.
The discharge time of the organic solvent-based developer is preferably 2 to 30 seconds, and more preferably 5 to 20 seconds.
In the case of a general 8 to 12 inch wafer, the total discharge amount of the organic solvent developer is preferably 3 to 50 ml, and more preferably 5 to 15 ml.
The rotation speed of the wafer is preferably 5 to 500 rpm and more preferably 5 to 250 rpm in the case of a general 8 to 12 inch wafer.
The swing time of the wafer is preferably 2 to 100 seconds, and more preferably 5 to 60 seconds.
It is preferable that the wafer is rotated at an interval of 1 to 10 seconds and at a speed of 5 to 100 rpm for 0.1 to 5 seconds.
The discharge time of the rinsing liquid is preferably 2 to 100 seconds, and more preferably 5 to 60 seconds.
The rotation speed of the wafer is preferably 50 to 2000 rpm and more preferably 100 to 1800 rpm for a general 8 to 12 inch wafer.
The details of the developing method are described in Japanese Patent No. 3765411, Japanese Patent Laid-Open No. 2001-85.
Examples include the methods described in JP-A No. 217 and JP-A No. 2007-319087.

The pattern forming method of the present invention may include a developing step using a water-based alkaline developer (positive pattern forming step) in addition to a developing step using a developer containing a surfactant and an organic solvent. That is, double patterning may be performed in which the high exposure region of the resist film is dissolved in an aqueous alkaline solution and the low exposure region is dissolved in a developer containing a surfactant and an organic solvent. As a result, as shown in FIG. 1, an intermediate exposure amount (E2-E1) region remains without being developed, and an L / S pattern 3 having a half pitch of the exposure mask 2 can be formed on the wafer 4. The development step using an aqueous alkaline developer may be after or before the development step with a developer containing a surfactant and an organic solvent, but contains a surfactant and an organic solvent. It is preferable to carry out before the developing step with the developer. Moreover, it is preferable to perform a heating process before each development process.
The aqueous alkaline developer is not particularly limited, but an aqueous solution of tetramethylammonium hydroxide (TMAH) is usually used. An appropriate amount of alcohol or surfactant may be added to the alkaline developer.
The alkali concentration of the alkali developer is usually from 0.1 to 20% by mass.
The pH of the alkali developer is usually from 10.0 to 15.0.
In particular, an aqueous solution of 2.38% by mass of tetramethylammonium hydroxide is desirable.

  As a rinsing solution in the rinsing treatment performed after development using an alkaline developer, pure water can be used, and an appropriate amount of a surfactant can be added.

It is not limited to the light source wavelength used for the exposure apparatus in the present invention, KrF excimer laser (wavelength 48 nm), ArF excimer laser (the wavelength 193 nm) _{F 2} excimer laser (wavelength 157nm), EUV (13nm), an electron beam (EB ), X-rays or the like can be applied.

The resist film of the present invention may be exposed (immersion exposure) by filling a liquid (immersion medium) having a higher refractive index than air between the film and the lens during irradiation with actinic rays or radiation. . Thereby, resolution can be improved. As the immersion medium to be used, any liquid can be used as long as it has a higher refractive index than air, but pure water is preferred.
In this case, a hydrophobic resin (HR), which will be described later, may be added in advance to the chemically amplified resist composition, and after the resist film is formed, an immersion liquid hardly soluble film (hereinafter referred to as an immersion liquid) , Also referred to as “top coat”).
The performance required for the top coat and how to use it are explained in chapter 7 of CM Publishing “Immersion Lithography Processes and Materials”.
From the viewpoint of transparency to a laser having a wavelength of 193 nm, the top coat is preferably a polymer that does not contain abundant aromatics. Specifically, the polymer is a hydrocarbon polymer, an acrylate polymer, polymethacrylic acid, polyacrylic acid, polyvinyl. Examples include ethers, silicon-containing polymers, fluorine-containing polymers. The hydrophobic resin (HR) described later is also suitable as a top coat. Commercially available top coat materials can also be used as appropriate.
When the topcoat is peeled after exposure, a developer may be used, or a separate release agent may be used. As the release agent, a solvent having low penetration into the film is preferable. From the viewpoint that the peeling step can be performed simultaneously with the development processing step of the film, it is preferable that the peeling step can be performed with a developer.

In the present invention, the substrate on which the film is formed is not particularly limited, and silicon, SiN, inorganic substrates such as SiO ₂ and SiN, coated inorganic substrates such as SOG, semiconductor manufacturing processes such as IC, liquid crystal, and thermal head For example, a substrate generally used in a circuit board manufacturing process or other photofabrication lithography process can be used. Further, if necessary, an organic antireflection film may be formed between the film and the substrate.

The processing solution of the present invention is a chemically amplified image forming method, preferably, the polarity of the composition is changed by deprotection of the protected polar group in the composition by the action of an acid, and the solution is dissolved in the developer. It is used in a chemically amplified image forming method for forming an image by changing the property. That is, it is used for development / rinsing treatment of a chemically amplified resist composition, and more preferably used for an ArF process (pattern formation process by ArF excimer laser exposure).
The chemically amplified resist composition comprises (A) a resin whose polarity is increased by the action of an acid and whose solubility in a developer containing an organic solvent is reduced, and (B) a compound that generates an acid upon irradiation with actinic rays or radiation. A so-called chemically amplified positive resist composition containing

<Chemically amplified resist composition>
Hereinafter, the chemically amplified resist composition that can be used in the present invention will be described.

[1] Resin whose polarity is increased by the action of an acid and whose solubility in a developer containing an organic solvent is reduced The polarity is increased by the action of an acid used in the chemically amplified resist composition of the present invention. Examples of the resin whose solubility in the developer containing it decreases include, for example, a group that decomposes into the main chain or side chain of the resin, or both the main chain and the side chain by the action of an acid to generate an alkali-soluble group (hereinafter, referred to as “resin”). A resin having an “acid-decomposable group” (hereinafter also referred to as “acid-decomposable resin” or “resin (A)”), and the polarity of this resin is increased by the action of an acid. It is also a resin that increases the solubility in a positive developer (aqueous alkaline developer).
Resin (A) is a resin (having a monocyclic or polycyclic alicyclic hydrocarbon structure, increased in polarity by the action of an acid, increased in solubility in an aqueous alkaline developer, and decreased in solubility in an organic solvent ( Hereinafter, it is also referred to as “alicyclic hydrocarbon-based acid-decomposable resin”).
In addition, the alicyclic hydrocarbon-based acid-decomposable resin tree can be suitably used when irradiating ArF excimer laser light.

The resin (A) is an acid-decomposable resin having a repeating unit having an acid-decomposable group.
A preferable group as the acid-decomposable group is a group in which a hydrogen atom of an alkali-soluble group is substituted with a group capable of leaving with an acid.
Preferred alkali-soluble groups include carboxyl groups, fluorinated alcohol groups (preferably hexafluoroisopropanol groups), and sulfonic acid groups.
The group capable of leaving with an acid is preferably an acetal group or a tertiary alkyl ester group, and more preferably a tertiary alkyl ester group.

  As the resin (A), a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by any of the following general formulas (pI) to (pV) and a repeating unit represented by the following general formula (II-AB) It is preferable that it is resin which has at least 1 sort (s) selected from the group of these.

In general formulas (pI) to (pV),
R ₁₁ represents a linear or branched alkyl group (preferably having 1 to 4 carbon atoms), and Z represents an atomic group necessary for forming a ring structure together with a carbon atom.
R _{12 to} R ₁₆ each independently represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms. Here, at least one of R _{12 to} R ₁₄ , or any of R ₁₅ and R ₁₆ is preferably a cycloalkyl group.
R _{17 to} R ₂₁ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group. Here, at least one of R _{17 to} R ₂₁ is preferably a cycloalkyl group. Further, either R ₁₉ or R ₂₁ represents a linear or branched alkyl group or cycloalkyl group having 1 to 4 carbon atoms.
R _{22 to} R ₂₅ each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, or a cycloalkyl group. Here, at least one of R _{22 to} R ₂₅ is preferably a cycloalkyl group. R ₂₃ and R ₂₄ may be bonded to each other to form a ring.

In general formula (II-AB),
R ₁₁ ′ and R ₁₂ ′ each independently represents a hydrogen atom, a cyano group, a halogen atom or an alkyl group.
Z ′ represents an atomic group for forming an alicyclic structure containing two bonded carbon atoms (C—C).

Examples of the linear or branched alkyl group having 1 to 4 carbon atoms in the general formulas (pI) to (pV) and R _{12 to} R ₂₅ include, for example, methyl group, ethyl group, n-propyl group, isopropyl Group, n-butyl group, isobutyl group, sec-butyl group and the like.

The cycloalkyl group or the cycloalkyl group formed by Z and the carbon atom in R _{12 to} R ₂₅ may be monocyclic or polycyclic. Specific examples include groups having a monocyclo, bicyclo, tricyclo, tetracyclo structure or the like having 5 or more carbon atoms. The carbon number is preferably 6-30, and particularly preferably 7-25. These cycloalkyl groups may have a substituent.

  As further substituents of these alkyl groups and cycloalkyl groups, alkyl groups (1 to 4 carbon atoms), halogen atoms, hydroxyl groups, alkoxy groups (1 to 4 carbon atoms), carboxyl groups, alkoxycarbonyl groups (carbon numbers) 2-6). Examples of the substituent that the alkyl group, alkoxy group, alkoxycarbonyl group and the like may further have include a hydroxyl group, a halogen atom, and an alkoxy group.

  The structures represented by the general formulas (pI) to (pV) can be used for protecting alkali-soluble groups. The alkali-soluble group is preferably a structure in which a hydrogen atom of a carboxyl group or a sulfonic acid group is substituted with a structure represented by general formulas (pI) to (pV).

  As the repeating unit having an alkali-soluble group protected by the structure represented by the general formulas (pI) to (pV), a repeating unit represented by the following general formula (pA) is preferable.

Here, R represents a hydrogen atom, a halogen atom, or a linear or branched alkyl group having 1 to 4 carbon atoms. A plurality of R may be the same or different.
A is a single bond, an alkylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a sulfonamide group, a urethane group, or a group of two or more groups selected from the group consisting of a ureylene group. Represents. A single bond is preferable.
Rp ₁ represents an acid-decomposable site, and specifically represents any group of the above formulas (pI) to (pV).

Hereinafter, although the specific example of the repeating unit which has an acid-decomposable group is shown, this invention is not limited to this.
In the formula, Rx and Xa1 represent any of H, CH ₃ , and CH ₂ OH, and Rxa and Rxb each represent an alkyl group having 1 to 4 carbon atoms.

Examples of the halogen atom in the general formula (II-AB), R ₁₁ ′, and R ₁₂ ′ include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

Examples of the alkyl group in R ₁₁ ′ and R ₁₂ ′ include a linear or branched alkyl group having 1 to 10 carbon atoms.

  The atomic group for forming the alicyclic structure of Z ′ is an atomic group that forms a repeating unit of an alicyclic hydrocarbon which may have a substituent in a resin, and among them, a bridged type alicyclic group. An atomic group for forming a bridged alicyclic structure forming a cyclic hydrocarbon repeating unit is preferred.

  In the resin (A), the group decomposed by the action of an acid is a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the general formula (pI) to the general formula (pV), a general formula (II- It can be contained in at least one repeating unit among the repeating unit represented by AB) and the repeating unit of the copolymerization component described later. The group capable of decomposing by the action of an acid is preferably contained in a repeating unit having a partial structure containing an alicyclic hydrocarbon represented by general formula (pI) to general formula (pV).

  Specific examples of the repeating unit represented by the general formula (II-AB) include the following specific examples, but the present invention is not limited to these specific examples.

  The resin (A) preferably has a lactone group. As the lactone group, any group having a lactone structure can be used, but a group having a 5- to 7-membered lactone structure is preferable.

  The lactone structure portion may or may not have a substituent. Preferred substituents include alkyl groups having 1 to 8 carbon atoms, cycloalkyl groups having 4 to 7 carbon atoms, alkoxy groups having 1 to 8 carbon atoms, alkoxycarbonyl groups having 2 to 8 carbon atoms, carboxyl groups, halogen atoms, Examples include a hydroxyl group, a cyano group, and an acid-decomposable group.

As the repeating unit having a group having a lactone structure, at least one of R ₁₁ ′ to R ₁₂ ′ in the general formula (II-AB) has a lactone group, or represented by the following general formula (AI). Can be mentioned.

In general formula (AI),
Rb ₀ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.
Preferred substituents that the alkyl group represented by Rb ₀ may have include a hydroxyl group and a halogen atom.
Examples of the halogen atom for Rb ₀ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Rb ₀ is preferably a hydrogen atom, a methyl group or a trifluoromethyl group, particularly preferably a hydrogen atom or a methyl group.
Ab represents a single bond, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, or a divalent group obtained by combining these. A linking group represented by a single bond or —Ab ₁ —CO ₂ — is preferable. Ab ₁ is a linear or branched alkylene group, a monocyclic or polycyclic cycloalkylene group, and preferably a methylene group, an ethylene group, a cyclohexylene group, an adamantylene group, or a norbornylene group.
V represents an atomic group containing a lactone structure. Specifically, V is preferably an atomic group containing a lactone structure having a norbornane skeleton or a 7-oxanorbornane skeleton. V may be substituted with a polar group such as a carboxyl group, an alkoxycarbonyl group, an alkylcarbonyloxy group, or a cyano group.

  Specific examples of the repeating unit having a group having a lactone structure are given below, but the present invention is not limited thereto.

  The resin (A) preferably has a repeating unit having a hydroxyl group or a cyano group. This improves the substrate adhesion and developer compatibility. The repeating unit having a hydroxyl group or a cyano group is preferably a repeating unit having an alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group. The alicyclic hydrocarbon structure in the alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group is preferably an adamantyl group, a diamantyl group, or a norbornyl group. Preferred examples of the alicyclic hydrocarbon structure substituted with a hydroxyl group or a cyano group include a monohydroxyadamantyl group, a dihydroxyadamantyl group, a monohydroxydiamantyl group, a dihydroxyadamantyl group, and a norbornyl group substituted with a cyano group.

  Specific examples of the repeating unit having a hydroxyl group or a cyano group are given below, but the present invention is not limited thereto.

  Resin (A) may have a repeating unit represented by the following general formula (VIII).

In general formula (VIII):
Z ₂ represents —O— or —N (R ₄₁ ) —. R ₄₁ represents a hydrogen atom, a hydroxyl group, an alkyl group, or —OSO ₂ —R ₄₂ . R ₄₂ represents an alkyl group, a cycloalkyl group or a camphor residue. The alkyl group of R ₄₁ and R ₄₂ may be substituted with a halogen atom (preferably a fluorine atom) or the like.

  The resin (A) preferably has a repeating unit having an alkali-soluble group, and more preferably has a repeating unit having a carboxyl group. As the repeating unit having a carboxyl group, a repeating unit in which a carboxyl group is directly bonded to the main chain of the resin, such as a repeating unit of acrylic acid or methacrylic acid, or a carboxyl group is bonded to the main chain of the resin through a linking group. Either a repeating unit that is bonded, or a polymerization initiator or chain transfer agent having an alkali-soluble group is introduced at the end of the polymer chain during polymerization, and the linking group is a monocyclic or polycyclic hydrocarbon. You may have a structure.

  The resin (A) may further have a repeating unit having a group represented by the following general formula (F1). This improves line edge roughness performance.

In general formula (F1),
R _{50 to} R ₅₅ each independently represents a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _{50 to} R ₅₅ represents a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom.
Rxa represents a hydrogen atom or an organic group (preferably an acid-decomposable protective group, an alkyl group, a cycloalkyl group, an acyl group, or an alkoxycarbonyl group).

The alkyl group of R _{50 to} R ₅₅ may be substituted with a halogen atom such as a fluorine atom, a cyano group, etc., preferably an alkyl group having 1 to 3 carbon atoms, such as a methyl group or a trifluoromethyl group. be able to.
R _{50 to} R ₅₅ are preferably all fluorine atoms.

  Examples of the organic group represented by Rxa include an acid-decomposable protecting group and an optionally substituted alkyl group, cycloalkyl group, acyl group, alkylcarbonyl group, alkoxycarbonyl group, alkoxycarbonylmethyl group, alkoxymethyl group. , 1-alkoxyethyl group is preferable.

  Specific examples of the repeating unit having a group represented by the general formula (F1) are shown below, but the present invention is not limited thereto.

  The resin (A) may further have a repeating unit that has an alicyclic hydrocarbon structure and does not exhibit acid decomposability. This can reduce the elution of low molecular components from the resist film to the immersion liquid during immersion exposure. Examples of such a repeating unit include a repeating unit of 1-adamantyl (meth) acrylate, tricyclodecanyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like.

  In addition to the above repeating units, the resin (A) has polymerized units derived from monomers such as acrylic esters, methacrylic esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers and vinyl esters. It may be.

In the resin (A), the molar ratio of each repeating structural unit is the resist pattern dry etching resistance, standard developer suitability, substrate adhesion, resist profile, and further the general required performance of the resist composition, resolving power, heat resistance It is appropriately set to adjust the property, sensitivity, etc.
In the resin (A), the content of the repeating unit having an acid-decomposable group is preferably 10 to 60 mol%, more preferably 20 to 50 mol%, still more preferably 25 to 40 mol% in all repeating structural units. is there.
In the resin (A), the content of the repeating unit having a partial structure containing an alicyclic hydrocarbon represented by the general formulas (pI) to (pV) is preferably 20 to 70 mol% in all repeating structural units, More preferably, it is 20-50 mol%, More preferably, it is 25-40 mol%.
In the resin (A), the content of the repeating unit represented by the general formula (II-AB) is preferably 10 to 60 mol%, more preferably 15 to 55 mol%, still more preferably 20 in all repeating structural units. ˜50 mol%.
In the resin (A), the content of the repeating unit having a group having a lactone structure is preferably 10 to 70 mol%, more preferably 20 to 60 mol%, still more preferably 25 to 40 mol% in all repeating structural units. It is.
In the resin (A), the content of the repeating unit having an organic group having a polar group is preferably 1 to 40 mol%, more preferably 5 to 30 mol%, still more preferably 5 to 20 mol in all repeating structural units. %.

  In addition, the content of the repeating structural unit based on the monomer of the further copolymer component in the resin can also be appropriately set according to the performance of the desired resist. ) To 99 p% with respect to the total number of moles of the repeating structural unit having a partial structure containing an alicyclic hydrocarbon represented by (pV) and the repeating unit represented by the general formula (II-AB). The following is preferable, More preferably, it is 90 mol% or less, More preferably, it is 80 mol% or less.

  When the chemically amplified resist composition of the present invention is for ArF exposure, the resin (A) preferably has no aromatic group from the viewpoint of transparency to ArF light. Moreover, it is preferable that resin (A) does not have a fluorine atom and a silicon atom from a compatible viewpoint with the below-mentioned resin unevenly distributed on the film | membrane surface.

Resin (A) can be synthesized and purified according to a conventional method (for example, radical polymerization). For the synthesis method and purification method, refer to the description in Chapter 2 “Polymer synthesis” of “5th edition Experimental Chemistry Course 26 Polymer Chemistry” published by Maruzen Co., Ltd. The weight average molecular weight of the resin (A) is preferably 1,000 to 200,000, more preferably 1,000 to 20,000, and particularly preferably 1,000 to 15, as a polystyrene-converted value by the GPC method. 000.
The degree of dispersion (molecular weight distribution) is usually 1 to 5, preferably 1 to 3, more preferably 1.2 to 3.0, particularly preferably 1.2 to 2.0. . The smaller the degree of dispersion, the better the lithography performance.

In the chemically amplified resist composition of the present invention, the blending amount of the resin (A) in the entire composition is preferably 50 to 99.9% by mass, more preferably 60 to 99.0% by mass in the total solid content. is there.
In the present invention, the resins may be used alone or in combination.

[2] Compound that generates acid upon irradiation with actinic ray or radiation The chemically amplified resist composition of the present invention comprises a compound that generates acid upon irradiation with actinic ray or radiation (hereinafter also referred to as “acid generator”). contains.
Although it will not specifically limit as an acid generator if it is a well-known thing, Preferably the compound represented by the following general formula (ZI), (ZII), (ZIII) can be mentioned.

In the general formula (ZI),
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represents an organic group.
The carbon number of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1-30, preferably 1-20.
Two of R _{201 to} R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ to R _203, there can be mentioned an alkylene group (e.g., butylene, pentylene).
Z ⁻ represents a non-nucleophilic anion (an anion having an extremely low ability to cause a nucleophilic reaction).

Examples of Z ⁻ include a sulfonate anion (an aliphatic sulfonate anion, an aromatic sulfonate anion, a camphor sulfonate anion, etc.), a carboxylate anion (an aliphatic carboxylate anion, an aromatic carboxylate anion, an aralkyl carboxylate anion). Etc.), sulfonylimide anion, bis (alkylsulfonyl) imide anion, tris (alkylsulfonyl) methide anion, fluorinated phosphorus, fluorinated boron, fluorinated antimony and the like.

Z ⁻ includes an aliphatic sulfonate anion substituted with at least α-position of sulfonic acid with a fluorine atom, an aromatic sulfonate anion substituted with a fluorine atom or a group having a fluorine atom, and an alkyl group substituted with a fluorine atom. Bis (alkylsulfonyl) imide anions and tris (alkylsulfonyl) methide anions in which the alkyl group is substituted with a fluorine atom are preferred. The non-nucleophilic anion is more preferably a perfluoroaliphatic sulfonate anion (more preferably 4 to 8 carbon atoms), a benzenesulfonate anion having a fluorine atom, still more preferably a nonafluorobutanesulfonate anion, or perfluorooctane. A sulfonate anion, a pentafluorobenzenesulfonate anion, and a 3,5-bis (trifluoromethyl) benzenesulfonate anion.
From the viewpoint of acid strength, the pKa of the generated acid is preferably −1 or less in order to improve sensitivity.

_Examples of the organic group for R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include an aryl group (preferably having 6 to 15 carbon atoms), a linear or branched alkyl group (preferably having 1 to 10 carbon atoms), and a cycloalkyl group (having 3 carbon atoms). ~ 15 are preferred).
Of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ , at least one is preferably an aryl group, more preferably all three are aryl groups. As the aryl group, in addition to a phenyl group, a naphthyl group, and the like, a heteroaryl group such as an indole residue and a pyrrole residue can be used. These aryl groups may further have a substituent. Examples of the substituent include halogen atoms such as nitro groups and fluorine atoms, carboxyl groups, hydroxyl groups, amino groups, cyano groups, alkoxy groups (preferably having 1 to 15 carbon atoms), cycloalkyl groups (preferably having 3 to 15 carbon atoms). ), An aryl group (preferably 6 to 14 carbon atoms), an alkoxycarbonyl group (preferably 2 to 7 carbon atoms), an acyl group (preferably 2 to 12 carbon atoms), an alkoxycarbonyloxy group (preferably 2 to 2 carbon atoms). 7) and the like, but are not limited thereto.
Two selected from R ₂₀₁ , R ₂₀₂ and R ₂₀₃ may be bonded via a single bond or a linking group. Examples of the linking group include, but are not limited to, an alkylene group (preferably having 1 to 3 carbon atoms), —O—, —S—, —CO—, —SO 2 — and the like.

Preferred structures when at least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is not an aryl group include paragraphs 0047 and 0048 of JP-A No. 2004-233661, paragraphs 0040 to 0046 of JP-A No. 2003-35948, US Compounds exemplified as formulas (I-1) to (I-70) in Patent Publication No. 2003 / 0224288A1, and Formulas (IA-1) to (I) in U.S. Patent Publication No. 2003 / 0077540A1 IA-54) and cation structures such as compounds exemplified as formulas (IB-1) to (IB-24).
In particular, when at least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is not an aryl group, the following embodiment (1) or (2) is particularly preferable.
(1) At least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is a structure represented by Ar—CO—X—, and the remaining two are a linear or branched alkyl group or a cycloalkyl group. If. At this time, the remaining two linear or branched alkyl groups or cycloalkyl groups may be bonded to each other to form a ring structure. Here, Ar represents an aryl group which may have a substituent, and specifically, is the same as the aryl group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ . A phenyl group which may have a substituent is preferable. X represents an alkylene group which may have a substituent. Specifically, it is an alkylene group having 1 to 6 carbon atoms. Preferably it is a C1-C3 linear or branched alkylene group. The remaining two linear or branched alkyl groups or cycloalkyl groups preferably have 1 to 6 carbon atoms. These atomic groups may further have a substituent. Moreover, it is preferable that it mutually couple | bonds and forms the ring structure (preferably 5-7 membered ring).
(2) When at least one of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is an aryl group which may have a substituent, and the remaining two are a linear or branched alkyl group or a cycloalkyl group . At this time, as the aryl group, specifically, the same as the aryl group of R _201, R ₂₀₂ and R _203, a phenyl group or a naphthyl group is preferable. The aryl group preferably has any one of a hydroxyl group, an alkoxy group, and an alkyl group as a substituent. More preferably, it is a C1-C12 alkoxy group as a substituent, More preferably, it is a C1-C6 alkoxy group. The remaining two linear or branched alkyl groups or cycloalkyl groups preferably have 1 to 6 carbon atoms. These atomic groups may further have a substituent. Further, they may be bonded to each other to form a ring structure.

In general formulas (ZII) and (ZIII),
R ₂₀₄ to R ₂₀₇ each independently represents an aryl group, an alkyl group or a cycloalkyl group.

Aryl group, alkyl group of R ₂₀₄ to R _207, the cycloalkyl group, aryl group R ₂₀₁ to R ₂₀₃ in the compound of the aforementioned (ZI-1), an alkyl group, an aryl group described as a cycloalkyl group, an alkyl group And the same as the cycloalkyl group.
Aryl group, alkyl group of R ₂₀₄ to R _207, cycloalkyl groups may have a substituent. Examples of this substituent include those that the aryl group, alkyl group, and cycloalkyl group of R _{201 to} R ₂₀₃ in the aforementioned compound (ZI-1) may have.

Z ⁻ represents a non-nucleophilic anion, and examples thereof include the same as the non-nucleophilic anion of Z ^{− in} formula (ZI).

  Examples of the acid generator further include compounds represented by the following general formulas (ZIV), (ZV), and (ZVI).

In general formulas (ZIV) to (ZVI),
Ar ₃ and Ar ₄ each independently represents an aryl group.
R ₂₀₈ , R ₂₀₉ and R ₂₁₀ each independently represents an alkyl group, a cycloalkyl group or an aryl group.
A represents an alkylene group, an alkenylene group or an arylene group.

  Among acid generators, particularly preferred examples are listed below, but the present invention is not limited thereto.

An acid generator can be used individually by 1 type or in combination of 2 or more types.
The content of the acid generator in the chemically amplified resist composition is preferably 0.1 to 30% by mass, more preferably 0.1 to 20% by mass, and still more preferably, based on the total solid content of the composition. It is 0.5-15 mass%, Most preferably, it is 1-13 mass%.

[3] Basic compound The chemically amplified resist composition of the present invention preferably contains a basic compound.
The basic compound is preferably a nitrogen-containing organic basic compound.
Although the compound which can be used is not specifically limited, For example, the compound classified into the following (1)-(4) is used preferably.

  (1) Compound represented by the following general formula (BS-1)

In general formula (BS-1),
Each R independently represents a hydrogen atom, an alkyl group (straight or branched), a cycloalkyl group (monocyclic or polycyclic), an aryl group, or an aralkyl group. However, not all three Rs are hydrogen atoms.
Although carbon number of the alkyl group as R is not specifically limited, Usually, 1-20, Preferably it is 1-12.
Although carbon number of the cycloalkyl group as R is not specifically limited, Usually, 3-20, Preferably it is 5-15.
Although carbon number of the aryl group as R is not specifically limited, Usually, 6-20, Preferably it is 6-10. Specific examples include a phenyl group and a naphthyl group.
Although carbon number of the aralkyl group as R is not specifically limited, Usually, 7-20, Preferably it is 7-11. Specific examples include a benzyl group.
In the alkyl group, cycloalkyl group, aryl group or aralkyl group as R, a hydrogen atom may be substituted with a substituent. Examples of the substituent include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, a hydroxyl group, a carboxyl group, an alkoxy group, an aryloxy group, an alkylcarbonyloxy group, and an alkyloxycarbonyl group.
In the compound represented by the general formula (BS-1), it is preferable that only one of three Rs is a hydrogen atom, or all Rs are not hydrogen atoms.

Specific examples of the compound of the general formula (BS-1) include tri-n-butylamine, tri-n-pentylamine, tri-n-octylamine, tri-n-decylamine, triisodecylamine, dicyclohexylmethylamine, Tetradecylamine, pentadecylamine, hexadecylamine, octadecylamine, didecylamine, methyloctadecylamine, dimethylundecylamine, N, N-dimethyldodecylamine, methyldioctadecylamine, N, N-dibutylaniline, N, N- Examples include dihexylaniline, 2,6-diisopropylaniline, 2,4,6-tri (t-butyl) aniline.
In addition, a compound in which at least one R in the general formula (BS-1) is an alkyl group substituted with a hydroxyl group can be mentioned as one of preferable embodiments. Specific examples of the compound include triethanolamine and N, N-dihydroxyethylaniline.

The alkyl group as R may have an oxygen atom in the alkyl chain, and an oxyalkylene chain may be formed. As the oxyalkylene chain, —CH ₂ CH ₂ O— is preferable. Specific examples include tris (methoxyethoxyethyl) amine and compounds exemplified in column 3, line 60 and thereafter of US Pat. No. 6,040,112.

(2) Compound having a nitrogen-containing heterocyclic structure The heterocyclic structure may or may not have aromaticity. Moreover, you may have two or more nitrogen atoms, Furthermore, you may contain hetero atoms other than nitrogen. Specifically, compounds having an imidazole structure (2-phenylbenzimidazole, 2,4,5-triphenylimidazole, etc.), compounds having a piperidine structure (N-hydroxyethylpiperidine, bis (1,2,2,6) , 6-pentamethyl-4-piperidyl) sebacate), compounds having a pyridine structure (such as 4-dimethylaminopyridine), and compounds having an antipyrine structure (such as antipyrine and hydroxyantipyrine). A compound having two or more ring structures is also preferably used. Specific examples include 1,5-diazabicyclo [4.3.0] non-5-ene and 1,8-diazabicyclo [5.4.0] -undec-7-ene.

(3) Amine compound having a phenoxy group An amine compound having a phenoxy group has a phenoxy group at the terminal opposite to the nitrogen atom of the alkyl group of the amine compound. Examples of the phenoxy group include an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a carboxyl group, a carboxylic acid ester group, a sulfonic acid ester group, an aryl group, an aralkyl group, an acyloxy group, and an aryloxy group. It may have a substituent.
More preferably, it is a compound having at least one oxyalkylene chain between the phenoxy group and the nitrogen atom. The number of oxyalkylene chains in one molecule is preferably 3-9, more preferably 4-6. Among the oxyalkylene chains, —CH ₂ CH ₂ O— is preferable.
Specific examples include 2- [2- {2- (2,2-dimethoxy-phenoxyethoxy) ethyl} -bis- (2-methoxyethyl)]-amine and US Patent Application Publication No. 2007 / 0224539A1. The compounds (C1-1) to (C3-3) exemplified in paragraph [0066] of the above.

(4) Ammonium salt Ammonium salts are also used as appropriate. Preferred is hydroxide or carboxylate. More specifically, tetraalkylammonium hydroxide represented by tetrabutylammonium hydroxide is preferable.

  Other compounds that can be used in the chemically amplified resist composition of the present invention include compounds synthesized in Examples of JP-A No. 2002-363146, compounds described in Paragraph 0108 of JP-A No. 2007-298869, and the like. Is mentioned.

A basic compound is used individually or in combination of 2 or more types.
The usage-amount of a basic compound is 0.001-10 mass% normally on the basis of solid content of a chemically amplified resist composition, Preferably it is 0.01-5 mass%.
The molar ratio of acid generator / basic compound is preferably 2.5 to 300. That is, the molar ratio is preferably 2.5 or more from the viewpoints of sensitivity and resolution, and is preferably 300 or less from the viewpoint of suppressing the reduction in resolution due to pattern thickening over time until post-exposure heat treatment. This molar ratio is more preferably 5.0 to 200, and still more preferably 7.0 to 150.

[4] Surfactant The chemically amplified resist composition of the present invention may further contain a surfactant. As the surfactant, fluorine-based and / or silicon-based surfactants are preferable.
Surfactants corresponding to these include Megafac F176, Megafac R08 manufactured by Dainippon Ink and Chemicals, PF656, PF6320 manufactured by OMNOVA, Troisol S-366 manufactured by Troy Chemical, Sumitomo 3M Examples include Fluorad FC430 manufactured by Co., Ltd., polysiloxane polymer KP-341 manufactured by Shin-Etsu Chemical Co., Ltd., and the like.
Further, other surfactants other than fluorine-based and / or silicon-based surfactants can also be used. More specific examples include polyoxyethylene alkyl ethers and polyoxyethylene alkyl aryl ethers.

  In addition, known surfactants can be used as appropriate. Examples of the surfactant that can be used include surfactants described in [0273] et seq. Of US Patent Application Publication No. 2008 / 0248425A1.

Surfactants may be used alone or in combination of two or more.
The amount of the surfactant used is preferably 0.0001 to 2% by mass, more preferably 0.001 to 1% by mass, based on the total solid content of the resist composition.
On the other hand, when the amount of the surfactant added is small or not used, the surface unevenness of the hydrophobic resin is increased, thereby making the resist film surface more hydrophobic, and at the time of immersion exposure. Water followability can be improved. From this point of view, it is also preferable that the addition amount of the surfactant is 10 ppm or less, and it is more preferable that the surfactant is not contained.

[5] Solvent The solvent that can be used in preparing the chemically amplified resist composition is not particularly limited as long as it dissolves each component. For example, alkylene glycol monoalkyl ether carboxylate (propylene glycol monomethyl ether acetate) (PGMEA; 1-methoxy-2-acetoxypropane, etc.), alkylene glycol monoalkyl ether (propylene glycol monomethyl ether (PGME; 1-methoxy-2-propanol), etc.), lactate alkyl ester (ethyl lactate, methyl lactate, etc.) , Cyclic lactone (γ-butyrolactone, etc., preferably 4 to 10 carbon atoms), chain or cyclic ketone (2-heptanone, cyclohexanone, etc., preferably 4 to 10 carbon atoms), alkylene carbonate (ethylene Boneto, propylene carbonate), alkyl acetate such as carboxylic acid alkyl (butyl acetate is preferred), and the like alkoxy alkyl acetates (ethyl ethoxypropionate). Other usable solvents include, for example, the solvents described in US Patent Application Publication No. 2008 / 0248425A1 after [0244].

  Of the above, lactic acid alkyl esters, alkylene glycol monoalkyl ether carboxylates and alkylene glycol monoalkyl ethers are preferred.

These solvents may be used alone or in combination of two or more. When mixing 2 or more types, it is preferable to mix the solvent which has a hydroxyl group, and the solvent which does not have a hydroxyl group. The mass ratio of the solvent having a hydroxyl group and the solvent having no hydroxyl group is from 1/99 to 99/1, preferably from 10/90 to 90/10, and more preferably from 20/80 to 60/40.
As the solvent having a hydroxyl group, alkylene glycol monoalkyl ether and alkyl lactate ester are preferable, and as the solvent having no hydroxyl group, alkylene glycol monoalkyl ether carboxylate is preferable.

[6] Hydrophobic resin When the chemically amplified resist composition of the present invention is applied to so-called immersion exposure, a hydrophobic resin (HR) can be further added to the composition. As a result, when the hydrophobic resin (HR) is unevenly distributed on the surface of the resist film and the immersion medium is water, the receding contact angle of the resist film surface with respect to water when the resist film is formed is improved, and the immersion water followability is improved. Can be made. As the hydrophobic resin (HR), any resin can be used as long as the receding contact angle of the surface can be improved by addition, but a resin having at least one of fluorine atom and silicon atom is preferable.

The hydrophobic resin (HR) is preferably a resin having an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom, or an aryl group having a fluorine atom as a partial structure having a fluorine atom.
Preferred examples of the alkyl group having a fluorine atom, the cycloalkyl group having a fluorine atom, or the aryl group having a fluorine atom include groups represented by the following general formulas (F2) to (F4). The present invention is not limited to this.

In general formulas (F2) to (F4),
R _{57 to} R ₆₈ each independently represents a hydrogen atom, a fluorine atom or an alkyl group. However, at least one of R _{57 to} R ₆₁ , R _{62 to} R ₆₄ and R _{65 to} R ₆₈ is a fluorine atom or an alkyl group in which at least one hydrogen atom is substituted with a fluorine atom (preferably having a carbon number of 1 ~ 4). R _{57 to} R ₆₁ and R _{65 to} R ₆₇ are preferably all fluorine atoms. R ₆₂ , R ₆₃ and R ₆₈ are preferably an alkyl group (preferably having 1 to 4 carbon atoms) in which at least one hydrogen atom is substituted with a fluorine atom, and preferably a perfluoroalkyl group having 1 to 4 carbon atoms. Further preferred. R ₆₂ and R ₆₃ may be connected to each other to form a ring.

The hydrophobic resin (HR) is preferably a resin having an alkylsilyl structure (preferably a trialkylsilyl group) or a cyclic siloxane structure as a partial structure having a silicon atom.
Specific examples of the alkylsilyl structure or the cyclic siloxane structure include groups represented by the following general formulas (CS-1) to (CS-3).

In general formulas (CS-1) to (CS-3),
R _{12 to} R ₂₆ each independently represents a linear or branched alkyl group (preferably having 1 to 20 carbon atoms) or a cycloalkyl group (preferably having 3 to 20 carbon atoms).
L < ₃ > -L < ₅ > represents a single bond or a bivalent coupling group. As the divalent linking group, an alkylene group, a phenylene group, an ether group, a thioether group, a carbonyl group, an ester group, an amide group, a urethane group, or a urea group, or a single or two or more groups selected from the group consisting of A combination is mentioned.
n represents an integer of 1 to 5.

Furthermore, the hydrophobic resin (HR) may have at least one group selected from the following groups (x) to (z).
(X) Alkali-soluble group (y) Group that decomposes by the action of an aqueous alkaline developer and increases the solubility in the aqueous alkali developer (z) Group that decomposes by the action of an acid

  (X) Alkali-soluble groups include phenolic hydroxyl groups, carboxylic acid groups, fluorinated alcohol groups, sulfonic acid groups, sulfonamido groups, sulfonylimide groups, (alkylsulfonyl) (alkylcarbonyl) methylene groups, (alkylsulfonyl) ( Alkylcarbonyl) imide group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris (alkylsulfonyl) ) And a methylene group. Preferred alkali-soluble groups include fluorinated alcohol groups (preferably hexafluoroisopropanol), sulfonimide groups, and bis (carbonyl) methylene groups.

(Y) Examples of the group that decomposes by the action of the aqueous alkaline developer and increases the solubility in the aqueous alkaline developer include groups having a lactone structure, acid anhydride groups, acid imide groups, and the like. Is a group having a lactone structure.
As the repeating unit having a group (y) that is decomposed by the action of the aqueous alkaline developer and increases the solubility in the aqueous alkaline developer, the main chain of the resin, such as a repeating unit of an acrylate ester or methacrylate ester, is used. Is a repeating unit to which a group (y) that is decomposed by the action of an aqueous alkaline developer and increases the solubility in an aqueous alkaline developer is bonded, or a group (y) that increases the solubility in an aqueous alkaline developer. Either a polymerization initiator or a chain transfer agent having a hydrogen atom is introduced at the end of the polymer chain during polymerization.

  Specific examples of the repeating unit having a group (y) that increases the solubility in an aqueous alkaline developer include those similar to the repeating unit having a lactone structure exemplified in the above-mentioned resin.

  In the hydrophobic resin (HR), examples of the repeating unit having a group (z) capable of decomposing by the action of an acid are the same as the repeating unit having an acid-decomposable group listed above for the resin.

  The hydrophobic resin (HR) may further have a repeating unit represented by the following general formula (III).

In general formula (III):
Rc ₃₁ represents a hydrogen atom, an alkyl group, or an alkyl group which may be substituted by fluorine, a cyano group or -CH ₂ -O-Ra _c2 group. In the formula, _Rac2 represents a hydrogen atom, an alkyl group or an acyl group. R _c31 is preferably a hydrogen atom, a methyl group, a hydroxymethyl group or a trifluoromethyl group, particularly preferably a hydrogen atom or a methyl group.
R _c32 represents a group having an alkyl group, a cycloalkyl group, an alkenyl group, or a cycloalkenyl group. These groups may be substituted with a fluorine atom or a silicon atom.
L _c3 represents a single bond or a divalent linking group.

In general formula (III), the alkyl group represented by R _c32 is preferably a linear or branched alkyl group having 3 to 20 carbon atoms.
The cycloalkyl group is preferably a cycloalkyl group having 3 to 20 carbon atoms.
The alkenyl group is preferably an alkenyl group having 3 to 20 carbon atoms.
The cycloalkenyl group is preferably a cycloalkenyl group having 3 to 20 carbon atoms.
R _c32 is preferably an unsubstituted alkyl group or an alkyl group substituted with a fluorine atom.
The divalent linking group of L _c3 is preferably an ester group, an alkylene group (preferably having a carbon number of 1 to 5), an oxy group, a phenylene group, or an ester bond (a group represented by —COO—).

When hydrophobic resin (HR) has a fluorine atom, it is preferable that content of a fluorine atom is 10-80 mol% with respect to the molecular weight of hydrophobic resin (HR). Moreover, it is preferable that the repeating unit containing a fluorine atom is 30-100 mass% in all the repeating units of hydrophobic resin (HR).
When hydrophobic resin (HR) has a silicon atom, it is preferable that content of a silicon atom is 2-30 mol% with respect to the molecular weight of hydrophobic resin (HR). Moreover, it is preferable that the repeating unit containing a silicon atom is 20-100 mass% in all the repeating units of hydrophobic resin (HR).

  The weight average molecular weight of the hydrophobic resin (HR) in terms of standard polystyrene is preferably 1,000 to 100,000, more preferably 1,000 to 50,000, and even more preferably 2,000 to 15,000. is there. The molecular weight distribution (Mw / Mn, also referred to as dispersity) is preferably in the range of 1 to 3, more preferably 1 to 2.

  The hydrophobic resin (HR), like the resin of the component (B), naturally has few impurities such as metals, but the residual monomer and oligomer components are preferably close to 0 as much as possible.

  As the hydrophobic resin (HR), various commercially available products can be used, and can be synthesized and purified according to a conventional method (for example, radical polymerization). For the detailed synthesis and purification method, refer to the method described in the above-mentioned resin (A) and the description in Chapter 2 “Polymer synthesis” of “5th edition Experimental Chemistry Course 26 Polymer Chemistry” published by Maruzen Co., Ltd. I want.

  Specific examples of the hydrophobic resin (HR) are shown below, but the present invention is not limited thereto.

[7] Other components In addition to the components described above, the chemically amplified resist composition of the present invention is a dissolution inhibitor having a molecular weight of 3000 or less as described in carboxylic acid onium salts, Proceeding of SPIE, 2724, 355 (1996), etc. A compound, a dye, a plasticizer, a photosensitizer, a light absorber, and the like can be appropriately contained.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

Synthesis Example 1 <Synthesis of Resin (4)>
Under a nitrogen stream, 20 g of a 6/4 (mass ratio) mixed solvent of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether was placed in a three-necked flask and heated to 80 ° C. (solvent 1). Butyrolactone methacrylate, hydroxyadamantane methacrylate and 2-methyl-2-adamantyl methacrylate are dissolved in a mixed solvent of 6/4 (mass ratio) of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether at a molar ratio of 50/10/40. A 22 mass% monomer solution (200 g) was prepared. Furthermore, 8 mol% of polymerization initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) was added to the monomer, and the dissolved solution was added dropwise to (solvent 1) over 6 hours. After completion of dropping, the reaction was further continued at 80 ° C. for 2 hours. The reaction solution was allowed to cool and then poured into 1800 ml of hexane / 200 ml of ethyl acetate, and the precipitated powder was collected by filtration and dried to obtain 37 g of Resin (4).
As a result of GPC measurement using polystyrene as a standard, the obtained resin (4) had a weight average molecular weight (Mw) of 8800 and a dispersity (Mw / Mn) of 1.8.
Similarly, resins (1), (2), (3), (5) and hydrophobic resins (1b), (2b), (3b) were synthesized.

  The structures of the resins (1) to (5) and the hydrophobic resins (1b) to (3b) are shown below. The composition of repeating units (corresponding to each repeating unit in order from the left), weight average molecular weight (Mw) and dispersion The degree (Mw / Mn) is shown in Table 1 below.

[Preparation of positive resist composition]
The components shown in Table 2 below were dissolved in a solvent, and a solution with a solid content of 3.5% by mass was prepared for each, and this was filtered through a polyethylene filter having a pore size of 0.1 μm, and a positive resist composition (Ar-01 ) To (Ar-06) were prepared.

  The (b) acid generator, (c) basic compound, (d) surfactant, and solvent shown in Table 2 are as follows.

  [(B) Acid generator]

[(C) Basic compound]
TPI: 2,4,5-triphenylimidazole PEA: N-phenyldiethanolamine DPA: 2,6-diisopropylphenyl alcohol PBI: 2-phenylbenzimidazole

[(D) Surfactant]
W-1: MegaFuck F176 (Dainippon Ink Chemical Co., Ltd.) (Fluorine)
W-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd.) (fluorine and silicon)
W-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) (silicon-based)

〔solvent〕
A1: Propylene glycol monomethyl ether acetate A3: Cyclohexanone B1: Propylene glycol monomethyl ether B2: Ethyl lactate

[Preparation of organic solvent developer and negative rinse]
The components shown in Tables 3 and 4 below were mixed at the mass ratios shown in Tables 3 and 4, and organic solvent developers (D-01) to (D-12), (Dr-01) to (Dr-02) and Negative rinses (R-01) to (R-12) and (Rr-01) to (Rr-02) were prepared.

  Abbreviations in Tables 4 to 5 are as follows.

〔solvent〕
PGME: Propylene glycol monomethyl ether

〔Additive〕
S-1: Megafac F176 (Dainippon Ink Chemical Co., Ltd., anionic, fluorine)
S-2: Megafuck R08 (Dainippon Ink Chemical Co., Ltd., nonion, fluorine)
S-3: Polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd., nonionic, silicon-based)
S-4: PF656 (manufactured by OMNOVA, nonionic, fluorine-based)
S-5: PF6320 (manufactured by OMNOVA, nonionic, fluorine-based)
S-6: Troisol S-366 (manufactured by Troy Chemical Co., Ltd.)
S-7: Fluorard FC430 (Sumitomo 3M, Fluorine)
S-8: Polyoxyethylene lauryl ether (Emulgen 103 manufactured by Kao Corporation)

Examples 1-1 to 1-15 and Comparative Examples 1-1 to 1-2
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on an 8-inch silicon wafer, and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 86 nm. A positive resist composition (Ar-01) was applied thereon and baked (PB) at 115 ° C. for 60 seconds to form a resist film having a thickness of 100 nm. The obtained wafer was subjected to pattern exposure using an ArF excimer laser scanner (NA 0.75) and using an exposure mask (line / space = 1/1). After heating at 105 ° C. for 60 seconds (PEB), developing with an organic solvent developer (D-01) for 30 seconds (organic solvent development), rinsing with a negative rinse solution (R-01), and then rotating at 4000 rpm The wafer was rotated for 30 seconds to obtain a 90 nm (1: 1) line and space resist pattern.
As Examples 1-2 to 1-15 and Comparative Examples 1-1 to 1-3, positive resist compositions, organic solvent developers, and negative rinses shown in Table 5 below were used, and PB conditions and PEB shown in Table 5 were used. A 90 nm (1: 1) line-and-space resist pattern was obtained in the same manner as in Example 1-1 except that the conditions were used.

Example 2-1 and Comparative Example 2-1
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on an 8-inch silicon wafer, and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 86 nm. A positive resist composition (Ar-01) was applied thereon and baked (PB) at 115 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to pattern exposure using an ArF excimer laser scanner (NA 0.75) through an exposure mask (line / space = 1/1). Thereafter, heating (PEB) at 105 ° C. for 60 seconds, developing with a tetramethylammonium hydroxide aqueous solution (2.38% by mass) (positive developer) for 30 seconds (positive development), rinsing with pure water, A pattern having a pitch of 600 nm and a line width of 450 nm was obtained. Next, the film was developed with an organic solvent developer (D-01) for 30 seconds (organic solvent development), rinsed with a negative rinse solution (R-01), and then rotated at a rotation speed of 4000 rpm for 30 seconds to obtain 150 nm. A (1: 1) line and space resist pattern was obtained.
As Comparative Example 2-1, a 150 nm (1: 1) line-and-space resist pattern was obtained in the same manner as in Example 2-1, except that the organic solvent developer (Dr-01) was used.

Example 3-1 and Comparative Example 3-1
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on an 8-inch silicon wafer, and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 86 nm. A positive resist composition (Ar-01) was applied thereon and baked (PB) at 115 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to pattern exposure using an ArF excimer laser scanner (NA 0.75) through an exposure mask (line / space = 1/1). After heating at 105 ° C. for 60 seconds (PEB), developing with an organic solvent developer (D-01) for 30 seconds (organic solvent development), rinsing with a negative rinse solution (R-01), and then rotating at 4000 rpm Then, a pattern with a pitch of 600 nm and a line width of 450 nm was obtained by rotating the wafer for 30 seconds. Next, the film was developed with a tetramethylammonium hydroxide aqueous solution (2.38% by mass) (positive developer) for 30 seconds (positive development), rinsed with pure water, and 150 nm (1: 1) line and space. A resist pattern was obtained.
As Comparative Example 3-1, a 150 nm (1: 1) line-and-space resist pattern was obtained in the same manner as in Example 3-1, except that the organic solvent developer (Dr-01) was used.

Example 4-1 and Comparative Example 4-1
An organic antireflection film ARC29A (Nissan Chemical Co., Ltd.) was applied on an 8-inch silicon wafer, and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 86 nm. A positive resist composition (Ar-01) was applied thereon and baked (PB) at 115 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to first pattern exposure using an ArF excimer laser scanner (NA 0.75) via an exposure mask (line / space = 1/1). Next, the mask was rotated in a direction orthogonal to the first exposure, and a second pattern exposure was performed through this. After heating at 105 ° C. for 60 seconds (PEB), developing with an organic solvent developer (D-01) for 30 seconds (organic solvent development), rinsing with a negative rinse solution (R-01), and then rotating at 4000 rpm The hole pattern with a pitch of 180 nm and a hole size of 90 nm was obtained by rotating the wafer for 30 seconds.
As Comparative Example 4-1, a hole pattern having a pitch of 180 nm and a hole size of 90 nm was obtained in the same manner as in Example 4-1, except that the organic solvent developer (Dr-01) was used.

Example 5-1 and Comparative example 5-1
An organic antireflection film ARC29SR (manufactured by Nissan Chemical Industries, Ltd.) was applied on a 12-inch silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 97 nm. A positive resist composition (Ar-01) was applied thereon and baked (PB) at 115 ° C. for 60 seconds to form a resist film having a thickness of 100 nm. The obtained wafer was subjected to pattern exposure using an ArF excimer laser immersion scanner (NA 1.20) through an exposure mask (line / space = 1/1). Pure water was used as the immersion liquid. After heating at 105 ° C. for 60 seconds (PEB), developing with an organic solvent developer (D-01) for 30 seconds (organic solvent development), rinsing with a negative rinse (R-01), and a rotational speed of 1200 rpm Then, a pattern with a pitch of 120 nm and a line width of 60 nm was obtained by rotating the wafer for 30 seconds.
As Comparative Example 5-1, a resist pattern having a pitch of 120 nm and a line width of 60 nm was obtained in the same manner as in Example 5-1, except that the organic solvent developer (Dr-01) was used.

Example 6-1 and Comparative example 6-1
An organic antireflection film ARC29SR (manufactured by Nissan Chemical Industries, Ltd.) was applied on a 12-inch silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a thickness of 97 nm. A positive resist composition (Ar-01) was applied thereon and baked (PB) at 115 ° C. for 60 seconds to form a resist film having a thickness of 150 nm. The obtained wafer was subjected to first pattern exposure using an ArF excimer laser immersion scanner (NA 1.20) through an exposure mask (line / space = 1/1). Pure water was used as the immersion liquid. Next, the mask was rotated in a direction orthogonal to the first exposure, and a second pattern exposure was performed through this. After heating at 105 ° C. for 60 seconds (PEB), developing with an organic solvent developer (D-01) for 30 seconds (organic solvent development), rinsing with a negative rinse (R-01), and a rotational speed of 1200 rpm The hole pattern with a pitch of 90 nm and a hole size of 45 nm was obtained by rotating the wafer for 30 seconds.
As Comparative Example 6-1, a hole pattern having a pitch of 90 nm and a hole size of 45 nm was obtained in the same manner as in Example 6-1, except that the organic solvent developer (Dr-01) was used.

<Evaluation method>
〔defect〕
The number of development defects of the patterned wafers prepared in the above examples and comparative examples was measured using KLA-2360 manufactured by KLA-Tencor Corp., and the value obtained by dividing the obtained numerical value by the area of the inspection region was the number of defects ( Number / cm ² ). It shows that defect performance is so favorable that this value is small.

[In-plane uniformity (CDU)]
The line widths of the patterns produced in the above examples and comparative examples were measured using 9380-II manufactured by Hitachi, Ltd., and 50 points were measured randomly from the entire area within the wafer surface, and this standard deviation was obtained. . A smaller value indicates better in-plane uniformity.
The evaluation results are shown in Table 5.

  From Table 5, it is clear that a resist pattern excellent in in-plane uniformity (CDU) and defect performance of the resist pattern can be formed by using the processing liquid for pattern formation by the chemically amplified resist composition of the present invention. It is.

1 Irradiation light 2 Exposure mask 3 Resist pattern 4 Wafer

Claims (13)

A processing solution for pattern formation by a chemically amplified resist composition , comprising a surfactant and an organic solvent , wherein the processing solution is a developer or a rinsing solution, and the water content of the processing solution is A processing liquid for pattern formation, which is less than 10% by mass .   The processing solution for pattern formation by the chemically amplified resist composition according to claim 1, wherein the processing solution is a developer. The processing liquid for pattern formation by the chemically amplified resist composition according to claim 2, wherein the developer contains an ester solvent. The processing liquid for pattern formation by the chemically amplified resist composition according to claim 2, wherein the developer contains butyl acetate.   2. A pattern forming treatment solution using a chemically amplified resist composition according to claim 1, which is a rinse solution. The processing liquid for pattern formation by the chemically amplified resist composition according to claim 5, wherein the rinse liquid contains an alcohol solvent. The processing liquid for pattern formation by the chemically amplified resist composition according to claim 5, wherein the rinsing liquid contains 4-methyl-2-pentanol. A pattern forming method comprising a step of forming a resist film using a chemically amplified resist composition, exposing, and developing using a developer containing a surfactant and an organic solvent , The pattern forming method, wherein the water content of the developer is less than 10% by mass . The pattern forming method according to claim 8, wherein the developer contains an ester solvent. The pattern forming method according to claim 8, wherein the developer contains butyl acetate. A pattern comprising a step of forming a resist film using a chemically amplified resist composition, exposing, developing using a developer, and rinsing with a rinsing solution containing a surfactant and an organic solvent. It is a formation method , Comprising: The moisture content of the said rinse liquid is less than 10 mass%, The pattern formation method characterized by the above-mentioned . The pattern forming method according to claim 11, wherein the rinse liquid contains an alcohol solvent. The pattern forming method according to claim 11, wherein the rinse liquid contains 4-methyl-2-pentanol.

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