TW201631413A - Composition for organic pattern embedding, pattern forming method and method for manufacturing electronic device - Google Patents

Abstract

This composition for organic pattern embedding contains a resin that has an Ohnishi parameter of more than 5.0. This pattern forming method and this method for manufacturing an electronic device comprise, in the following order: a step for forming a first resist film; a step for exposing the first resist film to light; a step for forming a first pattern; a step for forming a planarization layer; a step for forming a second resist film; a step for exposing the second resist film to light; and a step for forming a second pattern.

Description

Organic pattern embedding composition, pattern forming method, and electronic component manufacturing method

The present invention relates to a composition for embedding an organic pattern, a method for forming a pattern, a method for producing an electronic device, and an electronic device. More specifically, the present invention relates to a lithography process suitable for semiconductor manufacturing steps such as IC (Integrated Circuit), manufacturing of a circuit substrate such as a liquid crystal, a thermal head, and the like, and other photofabrication. (Lithography process) pattern forming method and organic pattern embedding composition used in the pattern forming method. Further, the present invention relates to a method of manufacturing an electronic component including the above pattern forming method and an electronic component manufactured by the method.

Conventionally, in the case of manufacturing a semiconductor element such as an IC, microfabrication is performed by photolithography using a resist composition. Here, in a damascene process or a dual pattern process (for example, LELE (Litho Etch Litoh Etch) method, LLE (Litho Litoh Etch) method, etc.), a planarization layer may be formed as a basis for forming a resist pattern (for example) , Patent Document 1). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2010-217306

In addition, the present inventors have found that the composition for forming a planarizing film disclosed in Patent Document 1 is used, for example, as a composition for flattening an organic pattern such as a resist pattern as in the pattern forming method of the present invention to be described later. In the case of a material (a composition for embedding an organic pattern), the embedding property and the flatness and etching property (high etching property) of the formed planarization layer do not necessarily satisfy the required level.

In view of the above-described circumstances, the present invention has an object of providing an organic pattern embedding composition excellent in embedding property, flatness, and etching property, a pattern forming method using the above composition, and a method of manufacturing an electronic component.

The inventors of the present invention have conducted intensive studies on the above problems and found that the above problems can be solved by using a resin having a larger Ohshin parameter than a specific ruthenium. In other words, the inventors of the present invention have found that the above problems can be solved by the following configuration.

(1) An organic pattern embedding composition containing a resin having a large West parameter of more than 5.0. (2) The organic pattern embedding composition according to the above (1), wherein the resin is at least 1 selected from the group consisting of a poly(meth)acrylate resin, a polyester resin, and a polyether resin. Kind of resin. (3) The organic pattern embedding composition according to the above (1), wherein the resin has a repeating unit represented by the following formula (1-1). (4) The organic pattern embedding composition according to the above (3), wherein, in the formula (1-1), R ₂ is a group containing a lactone structure, a group containing a carbonate structure, and contains B A group having an acetal structure, a group having a hydroxyl group, or a group represented by the following formula (P). (5) The organic pattern embedding composition according to the above (1), wherein the resin has a repeating unit represented by the following formula (1-2). The organic pattern embedding composition according to any one of the above aspects, wherein the resin does not contain an aromatic ring. (7) A pattern forming method comprising the steps of: forming a first resist film on a substrate using a first resist composition; and exposing the first resist film; The exposed first resist film is developed to form a first pattern, and the organic pattern embedding composition according to any one of the above (1) to (6) is provided with the first a step of forming a planarization layer on the substrate of the pattern; a step of forming a second resist film on the planarization layer using the second resist composition; and a step of exposing the second resist film; Developing the exposed second resist film to form a second pattern. (8) The pattern forming method according to the above (7), wherein the first pattern and/or the second pattern are patterns formed by development using a developing solution containing an organic solvent. (9) A method of producing an electronic component, comprising the pattern forming method according to (7) or (8) above.

As described below, according to the present invention, it is possible to provide an organic pattern embedding composition excellent in embedding property, flatness, and etching property, a pattern forming method using the above-described composition, and a method of manufacturing an electronic component.

Hereinafter, the best mode of the present invention will be described in detail. In the description of the group and the atomic group of the present specification, when neither a substitution nor an substitution is indicated, both of the substituents and the substituents are included. For example, it is not indicated that the substituted or unsubstituted "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). In the present invention, "actinic ray" or "radiation" means, for example, a particle beam such as a far-line ultraviolet ray, an extreme ultraviolet ray (EUV light), an X-ray, an electron beam, an ion beam or the like represented by a bright line spectrum of a mercury lamp or an excimer laser. Wait. Further, in the present invention, "light" means actinic rays or radiation. Moreover, the term "exposure" in the present specification includes not only exposure by far ultraviolet rays, X-rays, extreme ultraviolet rays (EUV light) represented by a mercury lamp, an excimer laser, but also including A particle beam such as an electron beam or an ion beam is drawn. In the present specification, "(meth) acrylate" means "at least one of acrylate and methyl acrylate". Further, “(meth)acrylic acid” means “at least one of acrylic acid and methyl acrylate”. In the present specification, the numerical range indicated by "~" means a range including the number 値 before and after the "~" as the lower limit 値 and the upper limit 値.

[Organic Pattern Buried Composition] The organic pattern embedding composition of the present invention (hereinafter also referred to as "the composition of the present invention") contains a resin having a large West parameter of more than 5.0. Since the composition of the present invention has such a structure, it can be considered to obtain a desired effect. Although the reason is not clear, it is presumed that by setting the Great West parameter of the resin to be larger than the specific enthalpy, the etching property is improved, and the polarity is improved, whereby the wettability is improved, and both the embedding property and the flatness can be achieved. In addition, in the present specification, the resin used for the organic pattern embedding composition is also referred to as "buried resin".

[Resin] As described above, the composition of the present invention contains a resin having a large West parameter of more than 5.0. Hereinafter, a resin having a large West parameter of more than 5.0 is also referred to as a "specific resin." The large West parameter of the specific resin is preferably from 5.5 to 20.0, more preferably from 6.0 to 15.0. Here, the Great West parameter of the resin is defined as follows. (Daxi parameter of resin) = Σ {(Daxi parameter of repeating unit) × (Mohr fraction of repeating unit)} Also, the Western parameter of the repeating unit is defined as follows. (Daxi parameter of repeating unit) = (total number of atoms in the repeating unit) / {(number of carbon atoms in the repeating unit) - (total of the number of oxygen atoms and sulfur atoms in the repeating unit)}

For example, the Great West parameter of A-1 used in the embodiment described later is calculated as follows. The total number of atoms of the first repeating unit of A-1 from the left is 22, the number of carbon atoms is 8, and the number of oxygen atoms is four, so the Western parameter is 22/(8-4)=5.5. The total number of atoms of the second repeating unit of A-1 from the left is 23, the number of carbon atoms is 7, and the number of oxygen atoms is 4, so the Daxi parameter is 23/(7-4) ≈7.7. The total number of atoms of the third repeating unit of A-1 from the left is 43, the number of carbon atoms is 7, and the number of oxygen atoms is four, so the Daxi parameter is 43/(13-6) ≈ 6.1. The molar fraction of the first repeating unit from the left of A-1 is 0.3, the molar fraction of the second repeating unit of A-1 from the left is 0.5, and the third repeating unit of A-1 from the left The molar fraction is 0.2, so considering the large West parameter of each of the above repeating units, the Great West parameter of A-1 is 5.5 × 0.3 + 7.7 × 0.5 + 6.1 × 0.2 ≈ 6.7.

The specific resin is not particularly limited as long as it has a resin having a large West parameter of more than 5.0, and specific examples thereof include a poly(meth)acrylate resin, a polyester resin, a polyether resin, a polystyrene resin, and a polyvinyl alcohol. Resin, polyoxyalkylene resin, and the like. Among them, at least one resin selected from the group consisting of poly(meth)acrylate resins, polyester resins, and polyether resins is preferred. It is preferred that the specific resin does not contain an aromatic ring.

The glass transition temperature (Tg) of the specific resin is not particularly limited, and is preferably 200 ° C or less, more preferably 60 ° C or less. The lower limit of Tg is not particularly limited and is usually -100 ° C or higher. From the standpoint of better embedding property and flatness, Tg is preferably lower. Further, the Tg is measured using a differential scanning calorimeter (DSC).

The weight average molecular weight of the specific resin is not particularly limited, and is preferably from 500 to 100,000, more preferably 20,000 or less, more preferably 15,000 or less, still more preferably 10,000 or less. In the present specification, the weight average molecular weight is a standard polystyrene equivalent enthalpy obtained by gel permeation chromatography (GPC) according to the following conditions.・Type of column: TSK SuperAWM-H (manufactured by TOSOH CORPORATION, 6.0mmID×150mm ・Expanding solvent: NMP (N-methyl-2-pyrrolidone) ・Column temperature: 50°C ・Flow rate: 0.35mL/min. Sample injection amount: 20 μL ・Device name: HLC-8220GPC (manufactured by TOSOH CORPORATION)

<First Preferred Aspect> The specific resin described above preferably has a repeating unit represented by the following formula (1-1). The specific resin may have two or more kinds of repeating units represented by the following formula (1-1).

[Chemical Formula 1]

In the formula (1-1), R ₁ represents a hydrogen atom or an organic group. R ₂ represents a hydrocarbon group having a hetero atom. The ratio of the number of hetero atoms contained in R _{2 to} the number of carbon atoms contained in R ₂ is 0.30 or more.

As described above, in the formula (1-1), R ₁ represents a hydrogen atom or an organic group. The organic group may, for example, be an alkyl group which may have a substituent such as a fluorine atom or a hydroxyl group, and a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group is preferred.

As described above, in the formula (1-1), R ₂ represents a hydrocarbon group having a hetero atom. The hetero atom is not particularly limited, and specific examples thereof include a nitrogen atom, an oxygen atom, and a sulfur atom. Among them, an oxygen atom is preferred. The hydrocarbon group having a hetero atom is not particularly limited, and examples thereof include an aliphatic hydrocarbon group having a hetero atom (for example, a carbon number of 1 to 10) (linear, branched, cyclic), and an aromatic hydrocarbon group having a hetero atom. (for example, a carbon number of 6 to 20), an alicyclic heterocyclic group, an aromatic heterocyclic group or a combination of these groups.

The ratio of the number of hetero atoms contained in R _{2 to} the number of carbon atoms contained in R ₂ (hereinafter also referred to as "R 2 hetero atom ratio") is 0.30 or more. Among them, 0.50 or more is preferred. The upper limit of the R2 hetero atom ratio is not particularly limited, and is usually 1.00 or less.

Examples of the above R ₂ include a hydrocarbon group, a group having a lactone structure, a group containing a carbonate structure, a group having an acetal structure, a group having a hydroxyl group, or a formula represented by the following formula (P). A group or the like, wherein a group having a lactone structure, a group containing a carbonate structure, a group having an acetal structure, a group having a hydroxyl group, or a group represented by the following formula (P) is preferred. . The hydrocarbon group is not particularly limited, and examples thereof include an aliphatic hydrocarbon group (for example, a carbon number of 1 to 10) (linear, branched, or cyclic), and an aromatic hydrocarbon group (for example, a carbon number of 6 to 20). Among them, an aliphatic hydrocarbon group is preferred. In the present specification, the repeating unit in which the R ₂ of the repeating unit represented by the formula (1-1) is a group having a lactone structure is represented by the following "repeating unit represented by the formula (1-1)" (R ₂ : a group having a lactone structure) (R ₂ is the same in the case of a hydrocarbon group having a hetero atom other than a group having a lactone structure).

The above group containing a lactone structure is a group having a lactone structure (cyclic ester structure). Specific examples of the lactone structure include a lactone structure which may also contain a "repeating unit having a lactone structure" of the resin (A) described later.

The above group containing a carbonate structure means a group containing a carbonate structure (cyclic carbonate structure). Specific examples of the carbonate structure include a cyclic carbonate structure in the "repeating unit having a cyclic carbonate structure" of the resin (A) to be described later.

The above group having an acetal structure means a group containing an acetal structure. Here, the acetal structure is represented by the following formula (Q).

[Chemical Formula 2] "

In the above formula (Q), R ₁ to R ₄ each independently represent a hydrocarbon group. The hydrocarbon group is not particularly limited, and examples thereof include an aliphatic hydrocarbon group (for example, a carbon number of 1 to 10) (linear, branched, or cyclic), and an aromatic hydrocarbon group (for example, a carbon number of 6 to 20). Among them, an aliphatic hydrocarbon group is preferred. R ₁ to R ₄ may be bonded to each other to form a ring.

The above hydroxyl group-containing group represents a group containing a hydroxyl group (-OH). Among them, a hydrocarbon group having a hydroxyl group is preferred. Specific examples and preferred embodiments of the hydrocarbon group are the same as those of R ₁ to R ₄ in the above formula (Q). The hydroxyl group-containing group is preferably a group containing two or more hydroxyl groups.

Hereinafter, the group represented by the formula (P) will be described.

[Chemical Formula 3]

In the formula (P), R _A represents a divalent hydrocarbon group. R _B represents a monovalent hydrocarbon group. n represents an integer of 1 or more. When n is an integer of 2 or more, a plurality of R _A may be the same or different. * indicates the bonding position.

As described above, R _A represents a divalent hydrocarbon group. Specific examples and preferred embodiments of the hydrocarbon group are the same as those of R ₁ to R ₄ in the above formula (Q). As described above, R _B represents a monovalent hydrocarbon group. Specific examples and preferred embodiments of the hydrocarbon group are the same as those of R ₁ to R ₄ in the above formula (Q). As described above, n represents an integer of 1 or more. An integer of n of from 1 to 10 is preferred.

In the first preferred embodiment, the ratio of the repeating unit (R ₂ : a group having a lactone structure) represented by the above formula (1-1) in the specific resin is preferably from 10 to 80 mol%, more preferably 10 to 10 60 mol% is more preferred. In the first preferred embodiment, the ratio of the repeating unit (R ₂ : a group containing a carbonate structure) represented by the above formula (1-1) in the specific resin is preferably from 10 to 80 mol%, more preferably 10 to 10 50 mol% is more preferred. In the first preferred embodiment, the ratio of the repeating unit represented by the above formula (1-1) (R ₂ : a group having an acetal structure) in the specific resin is preferably from 10 to 80 mol%, preferably 10 ～30 mol% is more preferred. In the first preferred embodiment, the ratio of the repeating unit represented by the above formula (1-1) (R ₂ : a group represented by the formula (P)) in the specific resin is preferably from 10 to 80 mol%. 10 to 30 mol% is more preferred.

In the first preferred embodiment, the ratio of the repeating unit represented by the above formula (1-1) in the specific resin (in the case of having two or more repeating units represented by the above formula (1-1), the total The ratio is not particularly limited, and is preferably from 10 to 100 mol%, more preferably from 80 to 100 mol%.

In the first preferred embodiment, the specific resin has a repeating unit represented by the above formula (1-1) (R ₂ : a group represented by the formula (P)), wherein the above formula (1) is used. 1) It is more preferable that the ratio of the repeating unit (R ₂ : a group represented by the formula (P)) is 15 mol% or more, in addition to the repeating unit represented by the above formula (1-1) (R ₂ : Further, in addition to the group represented by the formula (P), a repeating unit represented by the above formula (1-1) (R ₂ : a group having two or more hydroxyl groups) is further preferable.

In the first preferred embodiment, the specific resin may have a repeating unit other than the repeating unit represented by the above formula (1-1). For example, a repeating unit or the like having an R2 hetero atom ratio of less than 0.30 in the above formula (1-1) can be given.

<Second Best Aspect> The above resin preferably has a repeating unit represented by the following formula (1-2). The specific resin may have two or more kinds of repeating units represented by the following formula (1-2). [Chemical Formula 4]

In the formula (1-2), L represents a divalent hydrocarbon group. X represents -O-, -S- or -CO-O-.

As described above, L represents a divalent hydrocarbon group. Specific examples and preferred embodiments of the hydrocarbon group are the same as those of R ₁ to R ₄ in the above formula (Q).

In the second preferred embodiment, the ratio of the ratio (X: -O-) of the repeating unit represented by the above formula (1-2) in the specific resin is preferably from 20 to 100 mol%, preferably from 50 to 100 mol%. More preferably, 80 to 100 mol% is more preferable.

In the second preferred embodiment, the ratio of the repeating unit represented by the above formula (1-2) in the specific resin (in the case of having two or more repeating units represented by the above formula (1-2), the total The ratio is not particularly limited, and is preferably from 10 to 100 mol%, more preferably from 80 to 100 mol%.

In the composition of the present invention, the content of the specific resin is not particularly limited, and from 10 to 100% by mass, more preferably from 80 to 100% by mass, based on the total solid content.

[Optional Component] The composition of the present invention may contain components other than the specific resin. Examples of such a component include a resin, a solvent, a surfactant, and the like other than the specific resin. Specific examples of the solvent and the surfactant are the same as those of the resist composition described later. Further, the composition of the present invention preferably contains a solvent.

[Application] As described above, since the composition of the present invention is excellent in embedding property, flatness, and etching property, it can be preferably used in a flattening method used in the present invention to be described later or a pattern forming method of the present invention. The cloth is buried in a gap or the like of an organic pattern (for example, a resist pattern) formed on the surface of the substrate. The shape or size of the gap is not particularly limited, and may be a hole-like gap or a trench-like gap.

[Flatness Method and Pattern Forming Method] The planarization method used in the present invention sequentially includes the following steps: (A) a step of forming a first resist film on a substrate using the first resist composition; (B) a step of exposing the first resist film; (C) developing the exposed first resist film to form a first pattern; and (D) using the composition of the present invention described above, A step of forming a planarization layer on the substrate provided with the first pattern described above.

Further, the pattern forming method of the present invention further includes the following steps after the steps (A) to (D): (E) forming a second resist on the planarization layer using the second resist composition. a step of exposing the film; (F) a step of exposing the second resist film; and (G) developing the exposed second resist film to form a second pattern. Hereinafter, the "planarization method used in the present invention" and "the pattern formation method of the present invention" are also collectively referred to as "the method of the present invention".

It is preferable that the first pattern and/or the second pattern be a pattern formed by development using a developing solution containing an organic solvent.

In the method of the present invention, steps (A) to (G) can be carried out by a generally known method.

In the embodiment of the present invention, as shown in the schematic cross-sectional view of Fig. 1(a), first, the first resist film 52 is formed on the substrate 51 using the first resist composition (step (A)). . Here, the first resist composition preferably contains a resin which is increased in polarity by an action of an acid and which has a reduced solubility with respect to a developing solution (organic developing solution) containing an organic solvent. The reason is that, in particular, in this case, the first pattern obtained through the steps (B) and (C) described later contains a resin whose solubility with respect to the organic developing solution is lowered by exposure, so that the first pattern can be set. In the case of the composition of the present invention which is insoluble in the above, it is less susceptible to the influence of the solvent in the above-described composition of the present invention used in the step (D), and it is easy to form a desired pattern. In the following, the first resist composition and the first resist composition preferably contain a resin which is increased in polarity by an action of an acid and which has a reduced solubility with respect to a developer containing an organic solvent. The details are described.

In the step (A), the method of forming the first resist film on the substrate using the first resist composition can be typically performed by coating the first resist composition on the substrate as a coating In the method, it is preferable to apply the first resist composition by a spin coating method using a conventionally known spin coating method, spray coating method, roll coating method, dipping method, or the like.

The film thickness of the first resist film is preferably 20 to 160 nm, more preferably 25 to 140 nm, and still more preferably 30 to 120 nm.

The substrate 51 on which the first resist film is formed is not particularly limited, and an inorganic substrate such as ruthenium, SiN, SiO ₂ or SiN, a coated inorganic substrate such as SOG (Spin on Glass), or the like can be used, and an IC (Integrated Circuit) or the like can be used. A substrate commonly used in a semiconductor manufacturing step, a manufacturing process of a circuit board such as a liquid crystal or a thermal induction head, and a photolithography process of other photolithography processes. Further, an underlayer film such as an antireflection film may be formed between the first resist film and the substrate as needed. As the underlayer film, an organic antireflection film, an inorganic antireflection film, and the like can be appropriately selected. The underlying film material can be obtained from BREWER SCIENCE, INC., NISSAN CHEMICAL INDUSTRIES. LTD., and the like. The underlayer film which is suitable for the process of developing using a developing solution containing an organic solvent is, for example, an underlayer film described in WO2012/039337A.

It is also preferred to include a preheating step (PB; Prebake) between step (A) and step (B). Further, the method of the present invention preferably includes a post exposure heating step (PEB; Post Exposure Bake) between the step (B) and the step (C). The heating temperature of PB and PEB is preferably 70 to 130 ° C, more preferably 80 to 120 ° C. The heating time is preferably from 30 to 300 seconds, more preferably from 30 to 180 seconds, and further preferably from 30 to 90 seconds. The heating can be performed by a mechanism attached to a general exposure developing machine, or by using a heating plate or the like. The sensitivity or pattern distribution is improved by baking to promote the reaction of the exposed portion. At least one of the preheating step and the post-exposure heating step may also include a plurality of heating steps.

Next, as shown in the schematic cross-sectional view of FIG. 1(b), the resist film 52 is irradiated with actinic rays or radiation 71 (that is, exposure is performed) via the mask 61, whereby the first anti-exposure is obtained. Etchant film 53 (step (B)). Here, the mask pattern in the mask 61 is not particularly limited, and examples thereof include a line portion including a light shielding portion and a space portion having a light transmission portion, and a mask having a line and space pattern, that is, a line. The ratio of the width of the portion to the width of the space portion is a 1:3 mask. In the step (B), the wavelength of the light source used in the exposure apparatus is not particularly limited, and examples thereof include infrared light, visible light, ultraviolet light, far ultraviolet light, extreme ultraviolet light, X-ray, electron beam, etc., and preferably 250 nm or less. More preferably, it is 220 nm or less, and far ultraviolet light of a wavelength of 1 to 200 nm is particularly preferable, specifically, a KrF excimer laser (248 nm), an ArF excimer laser (193 nm), and an F ₂ excimer laser ( 157 nm), X-ray, EUV (13 nm), electron beam, etc., KrF excimer laser, ArF excimer laser, EUV or electron beam are preferred, and ArF excimer laser is more preferable. Step (B) may also include a plurality of exposure steps.

Further, in the step (B), a liquid immersion exposure method can be applied. Moreover, it is possible to combine super-resolution techniques such as a phase shift method and a deformed illumination method currently under study.

When the immersion exposure is performed, the first resist film may be exposed through the liquid immersion liquid before (1) the step of performing exposure after forming the first resist film on the substrate, and/or (2) The step of washing the surface of the first resist film with aqueous sputum is performed before the step of heating the first resist film after the step.

The liquid immersion liquid is transparent to the exposure wavelength, and a liquid having a temperature coefficient of the refractive index as small as possible to minimize the distortion of the optical image projected on the first resist film is preferable, but particularly In the case where the exposure light source is an ArF excimer laser (wavelength: 193 nm), in addition to the above viewpoints, it is preferable to use water from the viewpoints of easiness of acquisition and ease of handling.

When the first resist film formed using the first resist composition is exposed through a liquid immersion medium, the hydrophobic resin (D) described later can be further added as needed. The receding contact angle of the surface is increased by adding a hydrophobic resin (D). The receding contact angle of the first resist film is preferably 60 to 90, and more preferably 70 or more. In the immersion exposure step, as the exposure head is scanned at a high speed on the wafer to form an exposure pattern, it is necessary to move the liquid immersion liquid on the wafer, so that the liquid immersion liquid phase is in a dynamic state of the first resist film. The contact angle is very important, the droplets do not remain, and the resist is required to be accompanied by the high speed scanning performance of the exposure head.

In order to prevent the film from directly contacting the liquid immersion liquid between the first resist film formed using the first resist composition and the liquid immersion liquid, a liquid immersion liquid poorly soluble film may also be provided (hereinafter, also referred to as " Top coat".). The functions required for the composition for forming the top coat layer or the top coat layer include coating suitability applied to the upper portion of the resist, transparency with respect to radiation, particularly radiation having a wavelength of 193 nm, and The liquid immersion liquid is poorly soluble. It is preferable that the top coat layer-forming composition is not mixed with the resist, and it can be further uniformly applied to the upper layer of the resist.

Next, as shown in the schematic cross-sectional view of FIG. 1(c), the exposed first resist film 53 is developed to form a first pattern 54 (step (C)). Here, the step (C) is typically a step of developing the exposed first resist film by using a developing solution containing an organic solvent to form a first pattern, and the first pattern 54 is typically a negative pattern. In the step (C), the developer (hereinafter also referred to as "organic developer") in the step of developing the first pattern by developing the first resist film using a developer containing an organic solvent. A polar solvent such as a ketone solvent, an ester solvent, an alcohol solvent, a guanamine solvent or an ether solvent, or a hydrocarbon solvent can be used. Examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone (methyl amyl ketone), 4-heptanone, and 1- Hexone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetamidine, hexanedione, violet Ketone, diacetone alcohol, acetamethanol, acetophenone, methylnaphthyl ketone, isophorone, propylene carbonate and the like. Examples of the ester solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, amyl acetate, cyclohexyl acetate, and isobutyl isobutyrate. , propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxy propionate , 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate Ester, propyl lactate, isoamyl acetate, butyl butyrate, methyl 2-hydroxyisobutyrate, butyl propionate, and the like. Examples of the alcohol solvent include methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, isobutanol, n-hexanol, n-heptanol, n-octanol, and anthracene. An alcohol such as an alcohol or a glycol solvent such as ethylene glycol, diethylene glycol or triethylene glycol, or ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether or diethylene glycol alone A glycol ether solvent such as methyl ether, triethylene glycol monoethyl ether or methoxymethylbutanol. The ether solvent may, for example, be dioxane, tetrahydrofuran, phenethyl ether or dibutyl ether in addition to the above glycol ether solvent. As the guanamine-based solvent, for example, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, hexamethylphosphonium triamine, 1, can be used. 3-dimethyl-2-imidazolidinone and the like. Examples of the hydrocarbon solvent include an aromatic hydrocarbon solvent such as toluene or xylene, and an aliphatic hydrocarbon solvent such as pentane, hexane, octane or decane. The above solvent may be used in combination of plural kinds, or may be used in combination with a solvent or water other than the above. However, in order to sufficiently exhibit the effects of the present invention, it is preferred that the water content of the entire developer is less than 10% by mass, and it is more preferable that the water content is substantially not contained. In other words, the amount of the organic solvent to be used in the organic developer is preferably 90% by mass or more and 100% by mass or less based on the total amount of the developer, and more preferably 95% by mass or more and 100% by mass or less. In particular, the organic developer is preferably a developer containing at least one organic solvent selected from the group consisting of a ketone solvent, an ester solvent, an alcohol solvent, a guanamine solvent, and an ether solvent.

The vapor pressure of the organic developing solution is preferably 5 kPa or less at 20 ° C, more preferably 3 kPa or less, and particularly preferably 2 kPa or less. By setting the vapor pressure of the organic developer to 5 kPa or less, evaporation of the developer on the substrate or in the developing cup is suppressed, and temperature uniformity in the wafer surface is improved, and as a result, dimensional uniformity in the wafer surface is optimized.

An appropriate amount of a surfactant can be added to the organic developer as needed. The surfactant is not particularly limited, and for example, an ionic or nonionic fluorine-based and/or quinone-based surfactant can be used. For example, JP-A-62-36663, JP-A-61-226746, JP-A-61-226745, and JP-A-61-226745 Japanese Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. 5, 405, 520, U.S. Patent No. 5, 560, 520, U.S. Patent No. 5,360, 692, U.S. Patent No. 5,529, 881, U.S. Patent No. 5, 296, 730, U.S. Patent No. 5, 436, 830, U.S. Patent No. 5,576, 143, U.S. Patent No. 5,294,411 The surfactant described in the specification and the specification of U.S. Patent No. 5,824,451 is preferably a nonionic surfactant. The nonionic surfactant is not particularly limited, and a fluorine-based surfactant or a quinone-based surfactant is further preferably used. In general, the amount of the surfactant to be used is 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass, based on the total amount of the developer.

Further, a basic compound may be contained in the organic developer as needed. Examples of the basic compound include a nitrogen-containing basic compound, and the nitrogen-containing compound described in JP-A-2013-11833, in particular, <0021> to <0063>. When the organic-based developing solution contains a basic compound and the contrast during development is improved, it is expected to suppress thinning or the like.

Further, the resin which is increased in polarity by the action of an acid and which has reduced solubility with respect to the developer containing the organic solvent may be a resin which is increased in polarity by the action of an acid and which has an increased solubility with respect to the alkali developer. . Thereby, the method of the present invention may also be between step (B) and step (C) or between step (C) and step (D) (in the case of performing step (C') described later, step (C) And the step (C')) further having a step of performing development using an alkali developer. By combining development by an organic developer and development by an alkali developer, as described in FIGS. 1 to 11 of US Pat. No. 8,227,183 B, it is possible to expect a line of 1/2 of the mask pattern. The pattern of the width is resolved.

In the case where the method of the present invention further has a step of performing development using an alkali developer, as the alkali developer, for example, inorganic substances such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium citrate, sodium metasilicate, and ammonia can be used. Primary amines such as alkalis, ethylamines and n-propylamines, secondary amines such as diethylamine and di-n-butylamine, tertiary amines such as triethylamine and methyldiethylamine, and alcohol amines such as dimethylethanolamine and triethanolamine. An alkaline aqueous solution such as a quaternary ammonium salt such as tetramethylammonium hydroxide or tetraethylammonium hydroxide or a cyclic amine such as pyrrole or piperidine. Further, an appropriate amount of an alcohol or a surfactant may be added to the above alkaline aqueous solution for use. The above-mentioned one can be mentioned as a surfactant. 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. A 2.38 mass% aqueous solution of tetramethylammonium hydroxide is particularly preferred.

As a developing method, for example, a method of immersing a substrate in a tank filled with a developing solution for a certain period of time (dipping method), and a method of developing the substrate by using a surface tension on the surface of the substrate and holding it for a certain period of time can be applied (paddle method) A method of stirring (a stirring method), a method of spraying a developing solution onto a surface of a substrate (spraying method), a method of continuously discharging a developing solution while continuously scanning a developing solution discharge nozzle at a constant speed on a substrate rotating at a constant speed (dynamic stirring method).

The method of the present invention may also be between step (C) and step (D) (in the case of performing step (C') described later, between step (C) and step (C')), that is, in use After the developing solution of the organic solvent is subjected to the step of developing, it has a step of washing using a washing liquid containing an organic solvent (rinsing step).

The rinse liquid used in the rinsing step after the step of performing development using the developer containing the organic solvent is not particularly limited as long as the resist pattern is not dissolved, and a solution containing a usual organic solvent can be used. As the rinsing liquid, a rinsing liquid containing at least one organic solvent selected from the group consisting of a hydrocarbon solvent, a ketone solvent, an ester solvent, an alcohol solvent, a guanamine solvent, and an ether solvent is preferably used. . Specific examples of the hydrocarbon solvent, the ketone solvent, the ester solvent, the alcohol solvent, the guanamine solvent, and the ether solvent may be the same as those described in the developer containing the organic solvent. After the step of performing development using a developing solution containing an organic solvent, at least one organic solvent containing a group selected from the group consisting of a ketone solvent, an ester solvent, an alcohol solvent, a guanamine solvent, and a hydrocarbon solvent is used. The step of washing the rinse liquid is more preferably, and the step of washing with a rinse liquid containing a hydrocarbon solvent, an alcohol solvent or an ester solvent is further preferably carried out by washing with a rinse liquid containing a hydrocarbon solvent and a monohydric alcohol. It is particularly preferred that the step of washing with a rinse liquid containing a monohydric alcohol having 5 or more carbon atoms is preferred. Here, as the monohydric alcohol used in the rinsing step, a linear, branched, or cyclic monohydric alcohol may be mentioned, and specifically, 1-butanol, 2-butanol, or 3-methyl group can be used. 1-butanol, tert-butanol, 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, etc., as a particularly preferred monohydric alcohol having 5 or more carbon atoms, can be used. -hexanol, 2-hexanol, 4-methyl-2-pentanol, 1-pentanol, 3-methyl-1-butanol, and the like. As the rinse liquid containing a hydrocarbon solvent, a hydrocarbon compound having 6 to 30 carbon atoms is preferable, a hydrocarbon compound having 8 to 30 carbon atoms is more preferable, and a hydrocarbon compound having 10 to 30 carbon atoms is particularly preferable. Among them, pattern collapse can be suppressed by using a rinse liquid containing decane and/or undecane. When an ester solvent is used as the organic solvent, a glycol ether solvent may be used in addition to the ester solvent (one or two or more). Specific examples at this time include an ester solvent (preferable as butyl acetate) as a main component, and a glycol ether solvent (preferably propylene glycol monomethyl ether (PGME)) as a subcomponent. Thereby, residue defects can be further suppressed.

Each of the above components may be mixed in a plurality of types, or may be used in combination with an organic solvent other than the above.

Even in the case where the method of the present invention has a step of performing development using an alkali developer, a step of washing using a rinse liquid (rinsing step) may be included. As the rinsing liquid at this time, pure water is used, and an appropriate amount of a surfactant can also be added and used.

The method of the cleaning treatment in the above-described rinsing step is not particularly limited. For example, it can be applied to a method of continuously discharging a rinsing liquid on a substrate rotating at a constant speed (spin coating method), and immersing the substrate in a tank filled with the rinsing liquid for a certain period of time. a method (dipping method), a method of spraying a rinsing liquid onto a surface of a substrate (spraying method), or the like, wherein the cleaning treatment is performed by a spin coating method, and after the cleaning, the substrate is rotated at a number of revolutions of 2000 rpm to 4000 rpm to remove the rinsing liquid from the substrate. It is better. Also, after the rinsing step, a heating step (Post Bake) is also preferred. The developer and the rinse liquid remaining between the patterns and inside the pattern are removed by baking. The heating step after the rinsing step is usually carried out at 40 to 160 ° C, preferably 70 to 95 ° C, usually for 10 seconds to 3 minutes, preferably for 30 seconds to 90 seconds.

Further, after the development treatment or the rinsing treatment, the treatment of removing the developer or the rinsing liquid adhering to the pattern by the supercritical fluid can be performed.

Further, the heating step (C') may be further carried out between the step (C) and the step (D) which will be described later in detail, whereby the first pattern formed in the step (C) can be further improved as described above. The solvent resistance can be set even more so that the liquid composed of the above-described composition of the present invention is applied to the first pattern in the subsequent step (D). The temperature in the heating step (C') is preferably 130 ° C or more, more preferably 150 ° C or more, and further preferably 170 ° C or more. This temperature is usually 240 ° C or less. Further, the heating time in the heating step (C') is carried out for about 30 to 120 seconds. It is also preferable to carry out the heating step (C') under reduced pressure from the viewpoint of reducing the heating temperature by promoting the decomposition residue of the volatile organic substance and shortening the heating time.

Further, as described above, since the first pattern 54 has sufficient solvent resistance, it is not required, but the present invention is not intended to exclude the application of a known frozen material to the first pattern 54.

Next, as shown in the schematic cross-sectional view of FIG. 1(d), on the substrate 51 on which the first pattern 54 is formed, the planarization layer 81 is formed using the composition of the present invention described above (step (D)).

The method of forming the planarization layer using the composition of the present invention described above in the step (D) is the same as the method of forming the first resist film using the first resist composition in the above step (A). The thickness of the planarization layer having the surface of the first pattern as a reference surface is preferably 0 to 50 nm, more preferably 2 to 40 nm, and still more preferably 5 to 30 nm. Further, in a case where a planarization layer is formed in a space filled in a void portion of the first pattern, and a surface of the first pattern and a surface of the planarization layer are used to form a flat surface, the surface of the first pattern is used as a reference surface The film thickness of the planarization layer may also be 0 nm. In other words, the surface of the first pattern and the surface of the planarization layer may also be the same horizontal plane.

By the above steps (A) to (D), the first pattern is flattened.

As described above, the pattern forming method of the present invention further includes the following steps (E) to (G) after the above steps (A) to (D).

In the step (E), as shown in the schematic cross-sectional view of FIG. 1(e), on the substrate 51 on which the first pattern 54 is formed, the second resist film 56 is formed using the second resist composition. The second resist composition preferably contains a resin which is increased in polarity by the action of an acid and which has a reduced solubility with respect to the organic developer. The reason is that, in particular, in this case, the second pattern obtained through the steps (F) and (G) described later can be set to a negative pattern formed using an organic developing solution, so as described above, compared with the positive pattern It is possible to reliably form a gap pattern which is ultrafine (for example, a spacer width of 40 nm or less). Details of the second resist composition and preferably a resin containing the second resist composition which is increased in polarity by the action of an acid and reduced in solubility with respect to the developer containing the organic solvent It will be described later.

The method of forming the second resist film using the second resist composition in the step (E) is the same as the method of forming the first resist film using the first resist composition in the above step (A).

The preferred range of the film thickness of the second resist film is also the same as that described in the preferred range of the first resist film.

The pattern forming method of the present invention preferably includes a preheating step (PB; Prebake) between the step (E) and the step (F). Further, the pattern forming method of the present invention preferably includes a post exposure heating step (PEB; Post Exposure Bake) between the step (F) and the step (G). The heating temperature of PB and PEB is preferably 70 to 130 ° C, more preferably 80 to 120 ° C. The heating time is preferably from 30 to 300 seconds, more preferably from 30 to 180 seconds, and further preferably from 30 to 90 seconds. Heating can be performed by a mechanism attached to a general exposure developing machine, or by using a hot plate or the like. By baking, the reaction of the exposed portion is promoted, and the sensitivity or pattern distribution is improved. At least one of the preheating step and the post-exposure heating step may also include a plurality of heating steps.

Next, as shown in the schematic cross-sectional view of FIG. 1(f), the resist film 56 is irradiated with actinic rays or radiation 71 (that is, exposure is performed) via the mask 61, thereby obtaining a second resist for completion of exposure. Film 57 (step (F)). Here, the mask pattern in the mask 61 is not particularly limited, and the same as the mask used in the step (B), for example, includes a line portion as a light shielding portion and a space portion as a light transmission portion. A mask having a line and space pattern, that is, a mask having a ratio of the width of the line portion to the width of the space portion of 1:3). Further, the mask 61 is such that the position of the light shielding portion is shifted by a half pitch with respect to the position in the step (B) (that is, the line direction of the first pattern is finally parallel to the line direction of the second pattern, More specifically, it is preferable to arrange the center line of the space portion of the second pattern and the center line of the line portion of the first pattern when viewed from a direction perpendicular to the substrate, thereby implementing Step (G), step (H), and step (I) described later can form an ultrafine 1:1 line and space pattern.

The exposure method in the step (F) can be similarly employed in the exposure in the step (B).

Next, as shown in a schematic cross-sectional view of (g) of FIG. 1, the second resist film 57 which has been exposed is developed to form a second pattern 58 (step (G)). In the step (G), the developer which can be used in the step of developing the second resist film to form the second pattern may be an organic developer or an alkali developer, and the same step can be used in the same manner. The organic developing solution in (C) will be described, and the alkali developing solution in the above-mentioned "step of developing using an alkali developing solution" which can be carried out between step (C) and step (D) will be described. By. As the step (G), a step of forming a negative pattern as a second pattern using a developing solution containing an organic solvent and a step of forming a positive pattern as a second pattern using an alkali developing solution can be preferably used.

As described above, although the second pattern 58 may be a negative pattern or a positive pattern, as described above, from the viewpoint of reliably forming an ultrafine (for example, a gap width of 40 nm or less) gap pattern, negative The pattern is preferably, and the step (G) is preferably a step of forming a negative pattern as a second pattern using a developing solution containing an organic solvent.

Further, although the step (G) may have any one of a step of developing using an organic developing solution and a step of performing development using an alkali developing solution, it may have a step of developing using an organic developing solution and using an alkali developing solution. The steps of performing the development are not particularly limited in the order of the respective development steps at this time.

The developing method in the step (G) can be similarly used for the description of the step (C), and the above-mentioned "step of developing using an alkali developing solution" which can be carried out, for example, between the step (C) and the step (D). For the explanation.

Further, the pattern forming method of the present invention may further include a step of washing using a rinse liquid (washing step) after the step (G). The rinsing liquid in the rinsing step after the step of performing development using the organic developing solution can be similarly used in the step (rinsing step) which can be washed after the step (C) using the rinsing liquid containing the organic solvent. The rinsing liquid in the rinsing step after the step of performing development using the alkali developing solution can be similarly used, for example, and can be carried out between the step (C) and the step (D). The description will be made in the rinsing step after the step ”.

The method of the cleaning treatment in these rinsing steps can also be exemplified above.

By the above steps (A) to (G), the second pattern is formed on the planarization layer which planarizes the first pattern.

Step (H) and step (I) are further carried out on the substrate on which the second pattern is formed, whereby an ultrafine 1:1 line and space pattern can be formed.

As shown in the schematic cross-sectional view of FIG. 1(h), the step (H) uses the second pattern 58 as a mask, and the planarization layer 81 and the first pattern 54 are etched using an etching gas 75 or the like to form the first pattern. 54 is converted into a fine pattern 55.

The method of the etching treatment is not particularly limited, and various conditions and the like can be appropriately determined according to the type of the layer supplied to the etching treatment, etc., using a known method. For example, etching can be carried out in accordance with the International Society of Optical Engineering (Proc. of SPIE) Vol. 6924, 692420 (2008), and JP-A-2009-267112.

Here, a form in which at least one of the first pattern and the second pattern contains germanium atoms can be preferably used. In this embodiment, at least one of the first resist composition and the second resist composition contains a ruthenium atom (for example, a resin having a ruthenium atom) or at least one of the first pattern and the second pattern. A form of a germanium atom (for example, a resin having a germanium atom) is preferred. According to the above aspect, it is easy to set the etching rate of the first pattern to be sufficiently larger than the second etching by using an etching condition in which an etching reaction is easily generated on a film containing a germanium atom or an etching reaction in which a film containing no germanium atom is likely to generate an etching reaction. Etching conditions such as speed. Thereby, it is possible to more easily form the fine pattern 55 in which the pattern (pattern) of the second pattern 58 is transferred to the first pattern 54.

Next, as shown in the schematic cross-sectional view of (i) of FIG. 1, the planarization layer 81 and the second pattern 58 are removed (step (I)).

The step (I) is not particularly limited as long as the planarization layer and the second pattern can be removed, and at least one of the planarization layer and the second pattern can be selected from "etching treatment" and "exposure using a solvent" and One or more kinds of treatments "exposure using an aqueous solution (for example, an acidic aqueous solution or an alkaline aqueous solution)" are suitably carried out. That is, the same type of processing can be performed on the planarization layer and the second pattern, and different types of processing can be performed. In the step (I), it is preferable to remove the planarization layer 81 and the second pattern 58 without damaging the fine pattern 55, in other words, it is preferable to selectively remove the planarization layer 81 and the second pattern 58. In the illustrated process, it is preferable to selectively remove the planarization layer 81 and the second pattern 58.

In view of the above, etc., in the case where the planarization layer 81 is removed by an etching process, the step (I) includes an etching process in which the planarization layer 81 is subjected to a condition that the etching rate of the planarization layer 81 is larger than the etching rate of the fine pattern 55. The steps are preferred. In addition, in the case where the planarization layer 81 is removed by an etching process, the step of etching (I) including the step of performing the etching rate of the planarization layer 81 on the planarization layer 81 to be larger than the etching rate of the second pattern 58 is also performed. Preferably. The above conditions can be achieved by appropriately adjusting the contents of the respective compositions of the first resist composition, the second resist composition, and the above-described composition of the present invention, the type of etching gas, and the like. In particular, since the composition of the present invention described above is excellent in etching property, it is easy to achieve the above conditions.

As described above, the pattern forming method according to the embodiment of the present invention has been described. As in the above embodiment, the present invention typically has a pattern of the first pattern viewed from a direction perpendicular to the substrate and a second pattern viewed from a direction perpendicular to the substrate. The pattern does not completely overlap, forming a first pattern and a second pattern. Here, as in the above embodiment, it is preferable that the first pattern and the second pattern have a line having a line width larger than the interval width and a space. Especially in this case, it is preferable that the line direction of the first pattern is parallel to the line direction of the second pattern. Such an embodiment is preferable as an ultrafine pattern (for example, a line and space pattern having a line width and a gap width of 40 nm or less).

Further, in the pattern forming method according to the embodiment of the present invention, the first pattern and the second pattern are both lines and spaces, but the present invention is not limited to this embodiment, and for example, the first pattern and the second pattern may be mentioned. One of the patterns is a line and space pattern, and the other is a form of a hole pattern or a form in which the first pattern and the second pattern are both hole patterns. As described above, the type and size of each of the first pattern and the second pattern can be appropriately selected in accordance with the pattern of the fine pattern to be finally formed, and is not limited to a specific content.

Further, in the above-described embodiment of the present invention, after the step (G), another planarization layer may be further formed on the planarization layer provided with the second pattern by using the composition of the present invention described above, and then, The third resist composition forms a third resist film on the other planarization layer, and then the third resist film is subjected to exposure development to form a third pattern. According to this aspect, the second pattern is etched by using the third pattern as a mask, and the second pattern of the pattern after the third pattern is transferred can be formed by transferring the pattern of the third pattern. The second pattern is a mask, and the first pattern is etched to form a fine pattern in which the pattern of the second pattern and the pattern of the third pattern are transferred to the first pattern. As described above, the pattern forming method of the present invention may include a series of " further forming a planarization layer, further forming a resist film, and further patterning by exposure development of the resist film" after the step (G). Group of steps.

<First Resist Composition> A known composition can be used as the first resist composition (photosensitive ray-forming or radiation-sensitive resin composition). Also, the first resist composition is typically a chemically amplified resist composition.

[1] Resin having increased polarity by the action of an acid and reduced solubility with respect to a developing solution containing an organic solvent As described above, the first resist composition contains an increase in polarity by an action of an acid and is relatively A resin having a reduced solubility in a developer containing an organic solvent is preferred. As such a resin, for example, a group in which a polar group is formed by decomposition of an acid by a main chain or a side chain, a main chain, and a side chain of a resin (hereinafter, also referred to as "acid" The resin of the decomposable group ".) (hereinafter also referred to as "acid-decomposable resin" or "resin (A)"). It is preferred that the acid-decomposable group has a structure protected by a group decomposed by an action of an acid and desorbed from a polar group. The polar group is not particularly limited as long as it is insoluble or insoluble in a developing solution containing an organic solvent, and examples thereof include a phenolic hydroxyl group, a carboxyl group, and a fluorinated alcohol group (hexafluoroisopropanol group is preferred). ), sulfonic acid group, sulfonylamino group, sulfonimido group, (alkylsulfonyl) (alkylcarbonyl) methylene, (alkylsulfonyl) (alkylcarbonyl) fluorenylene, bis ( Alkylcarbonyl)methylene, bis(alkylcarbonyl)indenylene, bis(alkylsulfonyl)methylene, bis(alkylsulfonyl)indolylene, tris(alkylcarbonyl)methylene An acidic group such as a tris(alkylsulfonyl)methylene group (a group which is dissociated in a 2.38 mass% tetramethylammonium hydroxide aqueous solution which has been conventionally used as a resist) or an alcoholic hydroxyl group.

Further, the alcoholic hydroxyl group means a hydroxyl group bonded to a hydrocarbon group, that is, a hydroxyl group other than a hydroxyl group (phenolic hydroxyl group) directly bonded to an aromatic ring, and the hydroxyl group is substituted by an electron withdrawing group such as a fluorine atom. An aliphatic alcohol (for example, a fluorinated alcohol group (hexafluoroisopropanol group or the like)). The alcoholic hydroxyl group is preferably a hydroxyl group having a pKa of 12 or more and 20 or less.

Preferred examples of the polar group include a carboxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), and a sulfonic acid group.

A group which is preferably an acid-decomposable group is a group substituted with a group in which an acid is desorbed from a hydrogen atom of the group. Examples of the group which utilizes acid detachment include -C(R ₃₆ )(R ₃₇ )(R ₃₈ ), -C(R ₃₆ )(R ₃₇ )(OR ₃₉ ), and -C(R ₀₁ )(R). ₀₂ ) (OR ₃₉ ) and so on. In the formula, R ₃₆ to R ₃₉ each independently represent an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkenyl group. R ₃₆ and R ₃₇ may also be bonded to each other to form a ring. R ₀₁ and R ₀₂ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an arylalkyl group or an alkenyl group.

The alkyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an alkyl group having 1 to 8 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a n-butyl group, a sec-butyl group and a hexyl group. , 辛基, etc. The cycloalkyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ may be a monocyclic type or a polycyclic type. The monocyclic type is preferably a cycloalkyl group having 3 to 8 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. The polycyclic type is preferably a cycloalkyl group having 6 to 20 carbon atoms, and examples thereof include adamantyl group, norbornyl group, isobornyl group, fluorenyl group, dicyclopentyl group, and α-decenyl group (α). -pinenyl), tricyclodecyl, tetracyclo dodecyl group, androstanyl, and the like. Further, at least one carbon atom in the cycloalkyl group may be substituted with a hetero atom such as an oxygen atom. The aryl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group and an anthracenyl group. The aralkyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group. The alkenyl group of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ is preferably an alkenyl group having 2 to 8 carbon atoms, and examples thereof include a vinyl group, an allyl group, a butenyl group, and a cyclohexenyl group. As the ring formed by bonding R ₃₆ and R ₃₇ , a cycloalkyl group (monocyclic or polycyclic) is preferred. As a cycloalkyl group, a cyclopentyl group such as a cyclopentyl group or a cyclohexyl group, a monocyclic cycloalkyl group, a norbornyl group, a tetracyclodecyl group, a tetracyclo dodecanyl group, an adamantyl group or the like, a polycyclic cycloalkyl group. It is better. A monocyclic cycloalkyl group having 5 to 6 carbon atoms is more preferable, and a monocyclic cycloalkyl group having 5 carbon atoms is particularly preferable.

As the acid-decomposable group, a cumyl ester group, an enol ester group, an acetal ester group, a tertiary alkyl ester group or the like is preferable. A tertiary alkyl ester group is further preferred.

The resin (A) preferably contains a repeating unit having an acid-decomposable group.

Further, the resin (A) preferably has a repeating unit represented by the following formula (AI) as a repeating unit having an acid-decomposable group. By using a repeating unit represented by the general formula (AI), a carboxyl group as a polar group is produced by an action of an acid, and since it exhibits a high interaction by hydrogen bonding in a plurality of carboxyl groups, it can be more reliable. The formed negative pattern is insolubilized or poorly soluble with respect to the solvent in the above-described composition of the present invention.

[Chemical Formula 5]

In the general formula (AI), Xa ₁ represents a hydrogen atom, an alkyl group, a cyano group or a halogen atom. T represents a single bond or a divalent linking group. Rx ₁ to Rx ₃ each independently represent an alkyl group or a cycloalkyl group. Two of Rx ₁ to Rx ₃ may be bonded to form a ring structure.

Examples of the divalent linking group of T include an alkylene group, a -COO-Rt- group, a -O-Rt- group, and a phenylene group. In the formula, Rt represents an alkylene group or a cycloalkylene group. It is preferred that T is a single bond or a -COO-Rt- group. Rt is preferably an alkylene group having 1 to 5 carbon atoms, more preferably a -CH ₂ - group, a -(CH ₂ ) ₂ - group or a -(CH ₂ ) ₃ - group. T is a single bond for better.

The alkyl group of X _a1 may have a substituent, and examples of the substituent include a hydroxyl group and a halogen atom (a fluorine atom is preferred). The alkyl group having 1 to 4 carbon atoms of X _a1 is preferably a methyl group, an ethyl group, a propyl group, a hydroxymethyl group or a trifluoromethyl group, and a methyl group is preferred. It is preferred that X _a1 is a hydrogen atom or a methyl group.

The alkyl group of R _x1 , R _x2 and R _x3 may be linear or branched, and may preferably be a methyl group, an ethyl group, a n-propyl group, an isopropyl group or an n-butyl group. Isobutyl, tert-butyl and the like. The number of carbon atoms of the alkyl group is preferably from 1 to 10, more preferably from 1 to 5. _Examples of the cycloalkyl group of R _x1 , R _x2 and R _{x3 ,} a monocyclic cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, a norbornyl group, a tetracyclodecyl group, a tetracyclododecyl group or an adamantyl group. A cycloalkyl group is preferred.

a ring structure formed by two bonds of R _x1 , R _{x2 ,} and R _x3 , a cyclopentane ring such as a cyclopentane ring or a cyclohexene ring, a cyclodecane ring, a tetracyclodecane ring, or a tetracyclic ring A polycyclic cycloalkyl group such as a dialkyl ring or an adamantane ring is preferred. A monocyclic cyclopropane ring having 5 or 6 carbon atoms is particularly preferred.

R _x1 , R _x2 and R _x3 are each independently preferably an alkyl group, and more preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

Each of the above groups may have a substituent. Examples of the substituent include an alkyl group (having 1 to 4 carbon atoms), a cycloalkyl group (having 3 to 8 carbon atoms), a halogen atom, and an alkoxy group (carbon atom). The number is 1 to 4), a carboxyl group or an alkoxycarbonyl group (having 2 to 6 carbon atoms), and the number of carbon atoms is preferably 8 or less. Among them, from the viewpoint of further improving the dissolution contrast of the developer containing the organic solvent before and after the acid decomposition, the substituent having no hetero atom such as an oxygen atom, a nitrogen atom or a sulfur atom is more preferable (for example, not by a hydroxyl group). Further, a substituted alkyl group or the like is more preferable, and a group consisting only of a hydrogen atom and a carbon atom is further preferable, and a linear or branched alkyl group or a cycloalkyl group is particularly preferable.

In the general formula (AI), R _x1 to R _x3 are each independently an alkyl group, and it is preferred that two of R _x1 to R _x3 are bonded without forming a ring structure. Therefore, it is possible to suppress the increase in the volume of the group represented by -C(R _x1 )(R _x2 )(R _x3 ) which is a group which is decomposed and desorbed by the action of an acid, and can be exposed in the exposure step. And it is also possible to suppress volume shrinkage of the exposed portion during the post-exposure heating step performed after the exposure step.

Specific examples of the repeating unit represented by the general formula (AI) are given below, but the present invention is not limited to these specific examples. In a specific example, Rx represents a hydrogen atom, CH ₃ , CF ₃ or CH ₂ OH. Rxa and Rxb each independently represent an alkyl group (preferably having 1 to 10 carbon atoms and more preferably an alkyl group having 1 to 5 carbon atoms). Xa ₁ represents a hydrogen atom, CH ₃ , CF ₃ or CH ₂ OH. Z represents a substituent, and in the case where a plurality of substituents exist, a plurality of Z may be the same or different. p represents 0 or a positive integer. Specific examples and preferred examples of Z are the same as the specific examples and preferred examples of the substituents which each group such as Rx ₁ to Rx ₃ can have.

[Chemical Formula 6]

Further, the resin (A) is preferably a repeating unit described in paragraphs <0057> to <0071> of JP-A-2014-202969, and is preferably a repeating unit having an acid-decomposable group.

In addition, the resin (A) may have a repeating unit which generates an alcoholic hydroxyl group as described in paragraphs <0072> to <0073> of JP-A-2014-202969, as a repeating unit having an acid-decomposable group.

The repeating unit having an acid-decomposable group may be one type or two or more types may be used at the same time.

The content of the repeating unit having an acid-decomposable group contained in the resin (A) (in the case where a plurality of repeating units having an acid-decomposable group are present, in total) relative to the total repeating unit of the resin (A) It is preferably 15 mol% or more, more preferably 20 mol% or more, further preferably 25 mol% or more, and more preferably 40 mol% or more. Here, the resin (A) has a repeating unit represented by the above formula (AI), and the content of the repeating unit represented by the above formula (AI) with respect to the total repeating unit of the resin (A) is 40 mol% or more. Preferably. Further, the content of the repeating unit having an acid-decomposable group is preferably 80 mol% or less based on the total repeating unit of the resin (A), preferably 70 mol% or less, more preferably 65 mol% or less. .

The resin (A) may also contain a repeating unit having a lactone structure or a sultone structure.

The lactone structure or the sultone structure may be used arbitrarily as long as it has a lactone structure or a sultone structure, but a 5- to 7-membered ring lactone structure or a 5- to 7-membered cyclic sultone structure is preferred. Forming a bicyclic structure on a 5- to 7-membered ring lactone structure, a ring-ring structure in the form of a ring-ring structure, or a ring-ring structure in the form of a bicyclic structure or a spiro ring structure on a 5- to 7-membered ring sultone structure It is better to have other ring structures. It contains a lactone structure represented by any one of the following general formulae (LC1-1) to (LC1-21) or a sulfone represented by any one of the following general formulae (SL1-1) to (SL1-3) The repeating unit of the ester structure is further preferred. Also, the lactone structure or the sultone structure is directly bonded to the main chain. Preferred lactone structures are (LC1-1), (LC1-4), (LC1-5), (LC1-6), (LC1-13), (LC1-14), (LC1-17), A particularly preferred lactone structure is (LC1-4). By using this specific lactone structure, LER (Line Edge Roughness) and development defects become good.

[Chemical Formula 7]

The lactone moiety or the sultone moiety may have a substituent (Rb ₂ ) or may have no substituent (Rb ₂ ). Preferred examples of the substituent (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, and 2 carbon atoms. ～8 alkoxycarbonyl group, carboxyl group, halogen atom, hydroxyl group, cyano group, acid-decomposable group, and the like. More preferably, an alkyl group having 1 to 4 carbon atoms, a cyano group or an acid-decomposable group is used. n ₂ represents an integer of 0 to 4. When n ₂ is 2 or more, a plurality of substituents (Rb ₂ ) may be the same or different. Further, a plurality of substituents (Rb ₂ ) may be bonded to each other to form a ring.

The repeating unit having a lactone structure or a sultone structure usually has an optical isomer, but any optical isomer can be used. Further, one type of optical isomer may be used alone, or a plurality of optical isomers may be used in combination. When one optical isomer is mainly used, the optical purity (enantiomeric excess (ee)) is preferably 90% or more, more preferably 95% or more.

In the case where the resin (A) contains a repeating unit having a lactone structure or a sultone structure, the content of the repeating unit having a lactone structure or a sultone structure is 5 to 5 with respect to the total repeating unit in the resin (A). 60 mol% is preferred, 5 to 55 mol% is more preferred, and 10 to 50 mol% is further preferred.

Further, the resin (A) may also contain a repeating unit having a cyclic carbonate structure. The repeating unit having a cyclic carbonate structure is preferably a repeating unit represented by the following formula (A-1).

[Chemical Formula 8]

In the formula (A-1), R _A ¹ represents a hydrogen atom or an alkyl group. When n is 2 or more, R _A ² each independently represents a substituent. A represents a single bond or a divalent linking group. Z represents an atomic group which forms a monocyclic or polycyclic structure together with a group represented by -OC(=O)-O- in the formula. n represents an integer of 0 or more.

One type of the repeating unit represented by the formula (A-1) may be contained in the resin (A), and two or more kinds thereof may be contained. In the resin (A), the content of the repeating unit having a cyclic carbonate structure (the repeating unit represented by the formula (A-1) is preferable) is 3 to 80 with respect to the total repeating unit constituting the resin (A). Molar% is preferred, 3 to 60 mol% is further preferred, 3 to 30 mol% is particularly preferred, and 10 to 15 mol% is most preferred. By setting such a content ratio, it is possible to improve developability, low defect, low LWR (Line Width Roughness), low PEB temperature dependency, distribution, and the like as a resist.

The resin (A) may also contain a repeating unit having a hydroxyl group or a cyano group. Examples of the repeating unit include the repeating unit described in paragraphs <0081> to <0084> of JP-A-2014-098921.

Further, the resin (A) may also contain a repeating unit having an alkali-soluble group. Examples of the alkali-soluble group include a carboxyl group, a sulfonylamino group, a sulfonimide group, a bissulfonimide group, and an aliphatic alcohol (for example, a hexafluoroisopropanol group) in which the α-position is substituted with an electron withdrawing group. Examples of the repeating unit having an alkali-soluble group include the repeating unit described in paragraphs <0085> to <0086> of JP-A-2014-098921.

Further, the resin (A) can further contain a repeating unit having an alicyclic hydrocarbon structure and exhibiting no acid decomposition property, and the alicyclic hydrocarbon structure does not contain a polar group (for example, an alkali-soluble group, a hydroxyl group, a cyano group or the like). Examples of such a repeating unit include the repeating unit described in paragraphs <0114> to <0123> of JP-A-2014-106299.

Further, the resin (A) may contain, for example, a repeating unit described in paragraphs <0045> to <0065> of JP-A-2009-258586.

In order to adjust the dry etching resistance or the standard developer compatibility, the substrate adhesion, the resist profile, and the resolution, heat resistance, sensitivity, and the like which are generally required for the resist, in addition to the above repeating structural unit The resin (A) can also have various repeating structural units. Examples of such a repeating structural unit include repeating structural units corresponding to the following single-stranded bodies, but are not limited thereto. Thereby, the properties required for the resin (A), in particular, (1) solubility with respect to the coating solvent, (2) film forming property (glass migration point), (3) alkali developability, (4) The film formation (hydrophobicity, alkali-soluble group selection), (5) adhesion of the unexposed portion to the substrate, and (6) dry etching resistance are finely adjusted.

Examples of such a monovalent body include acrylates, methacrylates, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, and the like. A compound having one addition polymerizable unsaturated bond or the like. In addition, as long as it is an addition polymerizable unsaturated compound which can be copolymerized with a single amount corresponding to the above various repeating structural units, it can be copolymerized. In the resin (A), in order to adjust the dry etching resistance of the resist or the standard developer compatibility, the substrate adhesion, the resist profile, and the resolution, heat resistance, sensitivity, etc. which are generally required for the resist. The molar ratio of each repeating structural unit is appropriately set.

When the first resist composition is used for ArF exposure, it is preferable that the resin (A) has substantially no aromatic group from the viewpoint of transparency to ArF light. More specifically, in the total repeating unit of the resin (A), the repeating unit having an aromatic group is preferably 5 mol% or less in total, more preferably 3 mol% or less, and most preferably 0 mol%. That is, it is further preferred that the repeating unit having no aromatic group is contained. Further, the resin (A) preferably has a monocyclic or polycyclic alicyclic hydrocarbon structure.

Moreover, it is preferable that the resin (A) does not contain a fluorine atom and a ruthenium atom from the viewpoint of compatibility with a hydrophobic resin (D) to be described later.

As the resin (A), it is preferred that all of the repeating units are composed of (meth) acrylate repeating units. In this case, it is possible to use those in which the repeating units are all methyl acrylate-based repeating units, the repeating units are all acrylate-based repeating units, and the repeating units are all composed of a methyl acrylate-based repeating unit and an acrylate-based repeating unit. Either the acrylate-based repeating unit is preferably 50 mol% or less of the total repeating unit.

In the first resist composition, the compounding ratio of the entire composition of the resin (A) is preferably from 30 to 99% by mass, more preferably from 60 to 95% by mass, based on the total solid content. Further, in the present invention, the resin (A) may be used alone or in combination of plural kinds.

[2] Compound which generates an acid by irradiation with actinic rays or radiation The first resist composition contains a compound which generates an acid by irradiation with actinic rays or radiation (hereinafter also referred to as "acid generator"). ). The acid generator is not particularly limited, and a compound which generates an organic acid by irradiation with actinic rays or radiation is preferred. The acid generator can be appropriately selected from photoinitiator-polymerized photoinitiators, photoradical-polymerized photoinitiators, dye-based photodecolorizers, photochromic agents, and micro-resistors. A known compound which generates an acid by irradiation with an actinic ray or a radiation, and a mixture of the above, for example, a compound described in paragraphs <0039> to <0103> of JP-A-2010-61043, The compound described in paragraphs <0284> to <0389> of the Japanese Patent Publication No. 2013-4820, but the present invention is not limited thereto. For example, a diazonium salt, a phosphorus salt, a sulfonium salt, a sulfonium salt, a quinone imide sulfonate, an oxime sulfonate, a diazodiazine, a diterpene, an o-nitrobenzyl sulfonate can be mentioned.

As the acid generator to be contained in the first resist composition, for example, a compound (specific acid generator) which generates an acid by irradiation with actinic rays or radiation, which is represented by the following general formula (3), can be suitably used. .

[Chemical Formula 9]

(Anion) In the formula (3), Xf each independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. R ₄ and R ₅ each independently represent a hydrogen atom, a fluorine atom, an alkyl group or an alkyl group substituted with at least one fluorine atom. When a plurality of R ₄ and R ₅ are present in plural, they may be the same or different. L represents a divalent linking group, and when there are plural plural, L may be the same or different. W represents an organic group having a cyclic structure. o represents an integer from 1 to 3. p represents an integer of 0 to 10. q represents an integer of 0 to 10.

Xf represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. The alkyl group has preferably 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms. Further, an alkyl group substituted with at least one fluorine atom is preferably a perfluoroalkyl group. Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms. It is more preferable that Xf is a fluorine atom or CF ₃ . It is preferred that two Xf are fluorine atoms.

R ₄ and R ₅ each independently represent a hydrogen atom, a fluorine atom, an alkyl group or an alkyl group substituted with at least one fluorine atom. When a plurality of R ₄ and R ₅ are present in plural, they may be the same or different. The alkyl group as R ₄ and R ₅ may have a substituent, and those having 1 to 4 carbon atoms are preferred. It is preferred that R ₄ and R ₅ are a hydrogen atom. Specific examples and preferred embodiments of the alkyl group substituted with at least one fluorine atom are the same as the specific examples and the preferred embodiment of Xf in the formula (3).

L represents a divalent linking group, and when there are plural plural, L may be the same or different. Examples of the divalent linking group include -COO-(-C(=O)-O-), -OCO-, -CONH-, -NHCO-, -CO-, -O-, -S-, - SO-, -SO ₂ -, alkylene (preferably having 1 to 6 carbon atoms), cycloalkylene (preferably having 3 to 10 carbon atoms), and alkenylene (having 2 to 6 carbon atoms) Preferably, a plurality of the two-valent linking groups or the like are combined. Among these, -COO-, -OCO-, -CONH-, -NHCO-, -CO-, -O-, -SO ₂ -, -COO-alkylene-, -OCO-alkylene-, - CONH-alkylene- or -NHCO-alkylene- is preferred, -COO-, -OCO-, -CONH-, -SO ₂ -, -COO-alkylene- or -OCO-alkylene- For better.

W represents an organic group having a cyclic structure. Among them, a cyclic organic group is preferred. Examples of the cyclic organic group include an alicyclic group, an aryl group, and a heterocyclic group. The alicyclic group may be a single ring type or a polycyclic type. Examples of the monocyclic alicyclic group include a monocyclic cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic group include polycyclic cycloalkyl groups such as a norbornyl group, a tricyclic fluorenyl group, a tetracyclodecyl group, a tetracyclododecyl group, and an adamantyl group. Among them, from the viewpoint of suppressing the diffusibility in the film in the PEB (post-exposure heating) step and improving the MEEF (Mask Error Enhancement Factor), norbornyl, tricyclodecyl, tetracyclononyl, tetracyclododecane An alicyclic group having a structure having a large volume of 7 or more carbon atoms such as an adamantyl group or the like is preferred.

The aryl group may be a single ring type or a polycyclic type. Examples of the aryl group include a phenyl group, a naphthyl group, a phenanthryl group, and an anthracenyl group. Among them, a naphthyl group having a relatively low light absorbance in 193 nm is preferred. The heterocyclic group may be a monocyclic ring or a polycyclic ring, but the polycyclic ring is more resistant to the diffusion of an acid. Further, the heterocyclic group may have aromaticity or may not be aromatic. Examples of the aromatic heterocyclic ring include a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a pyridine ring. Examples of the heterocyclic ring having no aromaticity include a tetrahydropyran ring, a lactone ring, a sultone ring, and a decahydroisoquinoline ring. As the heterocyclic ring in the heterocyclic group, a furan ring, a thiophene ring, a pyridine ring or a decahydroisoquinoline ring is particularly preferable. Further, examples of the lactone ring and the sultone ring include the lactone structure and the sultone structure exemplified in the above resin.

The above cyclic organic group may have a substituent. The substituent may, for example, be an alkyl group (which may be either a straight chain or a branched chain, preferably having 1 to 12 carbon atoms) or a cycloalkyl group (which may be monocyclic, polycyclic or spiro). Any one, preferably having 3 to 20 carbon atoms, an aryl group (preferably having 6 to 14 carbon atoms), a hydroxyl group, an alkoxy group, an ester group, a decylamino group, a urethane group, or a urea group. a thiol group, a sulfonamide group, and a sulfonate group. Further, the carbon constituting the cyclic organic group (carbon which contributes to the formation of the ring) may also be a carbonyl carbon.

o represents an integer from 1 to 3. p represents an integer of 0 to 10. q represents an integer of 0 to 10. In one aspect, o in the formula (3) is an integer of 1 to 3, p is an integer of 1 to 10, and q is preferably 0. Xf is preferably a fluorine atom, R ₄ and R ₅ are each a hydrogen atom, and W is preferably a polycyclic hydrocarbon group. o is preferably 1 or 2, and 1 is further preferred. An integer of p is preferably from 1 to 3, more preferably 1 or 2, and particularly preferably 1. W is preferably a polycyclic cycloalkyl group, and adamantyl or diamantyl is further preferred.

(cation) In the formula (3), X ⁺ represents a cation. X ⁺ is not particularly limited as long as it is a cation, and examples of the preferred embodiment include cations (parts other than Z ^- ) in the following general formula (ZI), (ZII) or (ZIII).

(Optimal Aspect) As a preferable aspect of the specific acid generator, for example, a compound represented by the following formula (ZI), (ZII) or (ZIII) can be mentioned.

[Chemical Formula 10]

In the above formula (ZI), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represent an organic group. The organic group of R ₂₀₁ , R ₂₀₂ and R ₂₀₃ has usually 1 to 30, preferably 1 to 20 carbon atoms. Further, two of R ₂₀₁ to R ₂₀₃ may be bonded to each other to form a ring structure, and an oxygen atom, a sulfur atom, an ester bond, a guanamine bond or a carbonyl group may be contained in the ring. Examples of the group formed by bonding two of R ₂₀₁ to R ₂₀₃ include an alkylene group (for example, a butenyl group or a pentenyl group). Z ^- represents an anion in the formula (3), and specifically represents the following anion.

[Chemical Formula 11]

Examples of the organic group represented by R ₂₀₁ , R ₂₀₂ and R ₂₀₃ include the groups corresponding to the compounds (ZI-1), (ZI-2), (ZI-3) and (ZI-4) described below. Further, it may be a compound having a plurality of structures represented by the general formula (ZI). For example, at least one of R ₂₀₁ to R ₂₀₃ having a compound represented by the general formula (ZI) may be a single bond or a linking group and R ₂₀₁ to R ₂₀₃ of another compound represented by the general formula (ZI). A compound of at least one bonded structure.

Next, the general formulae (ZII) and (ZIII) will be described. In the general formulae (ZII) and (ZIII), R ₂₀₄ to R ₂₀₇ each independently represent an aryl group, an alkyl group or a cycloalkyl group. As the aryl group of R ₂₀₄ to R ₂₀₇ , a phenyl group or a naphthyl group is preferred, and a phenyl group is further preferred. The aryl group of R ₂₀₄ to R ₂₀₇ may be an aryl group having a heterocyclic structure containing an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the skeleton of the aryl group having a heterocyclic structure include pyrrole, furan, thiophene, anthracene, benzofuran, and benzothiophene. The alkyl group and the cycloalkyl group in R ₂₀₄ to R ₂₀₇ are preferably a linear or branched alkyl group having 1 to 10 carbon atoms (for example, a methyl group, an ethyl group, a propyl group or a butyl group). Pentyl), a cycloalkyl group having 3 to 10 carbon atoms (cyclopentyl group, cyclohexyl group, norbornyl group).

The aryl group, the alkyl group or the cycloalkyl group of R ₂₀₄ to R ₂₀₇ may have a substituent. The aryl group, the alkyl group or the cycloalkyl group of R ₂₀₄ to R ₂₀₇ may have a substituent, and examples thereof include an alkyl group (for example, a carbon number of 1 to 15) and a cycloalkyl group (for example, a carbon number of 3 to 15). And an aryl group (for example, a carbon number of 6 to 15), an alkoxy group (for example, a carbon number of 1 to 15), a halogen atom, a hydroxyl group, or a phenylthio group. Z ^- represents an anion in the formula (3), specifically as described above.

The acid generator (including a specific acid generator. The same applies hereinafter) may be in the form of a low molecular compound or a form in which a part of the polymer is incorporated. Further, the form of the low molecular compound and the form of a part of the polymer may be used at the same time. When the acid generator is in the form of a low molecular compound, the molecular weight is preferably 3,000 or less, more preferably 2,000 or less, and still more preferably 1,000 or less. When the acid generator is in the form of a part of the polymer, a part of the resin may be incorporated, or a resin different from the resin may be incorporated. The acid generator can be synthesized by a known method, and can be synthesized, for example, by the method described in JP-A-2007-161707. The acid generator can be used singly or in combination of two or more. The content of the acid generator in the composition (the total amount when a plurality of kinds are present) is preferably 0.1 to 30% by mass, more preferably 0.5 to 25% by mass, more preferably 3 to 20% by mass based on the total solid content of the composition. % is further preferred, and 3 to 15% by mass is particularly preferred. When the compound represented by the above formula (ZI-3) or (ZI-4) is contained as the acid generator, the content of the acid generator contained in the composition (when plural kinds are present, the total amount thereof) is The total solid content of the composition is preferably from 5 to 35% by mass, more preferably from 8 to 30% by mass, even more preferably from 9 to 30% by mass, even more preferably from 9 to 25% by mass.

[3] Hydrophobic Resin The first resist composition may also contain a hydrophobic resin (hereinafter also referred to as "hydrophobic resin (D)" or simply "resin (D)"). Further, the hydrophobic resin (D) is preferably different from the resin (A). The hydrophobic resin (D) is preferably designed to be biased at the interface, but unlike the surfactant, it is not necessary to have a hydrophilic group in the molecule, and it may not contribute to uniform mixing of polar and non-polar substances. Examples of the effect of adding the hydrophobic resin include control of static and dynamic contact angles of the surface of the resist film, improvement of liquid immersion liquid followability, suppression of degassing, and the like.

The hydrophobic resin (D) has one or more of a "fluorine atom", a "deuterium atom", and a "CH ₃ partial structure contained in a side chain portion of the resin" from the viewpoint of the surface layer of the film. Preferably, it is further preferable to have two or more types. In the case where the hydrophobic resin (D) contains a fluorine atom and/or a ruthenium atom, the above-mentioned fluorine atom and/or ruthenium atom in the hydrophobic resin (D) may be contained in the main chain of the resin or may be contained in the side chain. in.

In the case where the hydrophobic resin (D) contains a fluorine atom, as a partial structure having a fluorine atom, 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 is preferable. The alkyl group having a fluorine atom (preferably having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms) is a linear or branched alkyl group in which at least one hydrogen atom is substituted by a fluorine atom, and may further have A substituent other than a fluorine atom. The cycloalkyl group having a fluorine atom and the aryl group having a fluorine atom are each a cycloalkyl group in which one hydrogen atom is substituted by a fluorine atom, and an aryl group having a fluorine atom, and may further have a substituent other than a fluorine atom.

The alkyl group having a fluorine atom, the cycloalkyl group having a fluorine atom, and the aryl group having a fluorine atom are preferably those described in paragraphs <0287> to <0290> of JP-A-2014-202969. Group, but the invention is not limited thereto.

The hydrophobic resin (D) may also contain a ruthenium atom. As the partial structure having a ruthenium atom, a resin having an alkylformamidine structure (trialkylcarbenyl group is preferred) or a cyclic oxirane structure is preferred. Examples of the repeating unit having a fluorine atom or a ruthenium atom include those exemplified in US 2012/0251948 A1 [0519].

Further, as described above, the hydrophobic resin (D) preferably has a CH ₃ moiety structure in the side chain portion. Here, the hydrophobic side chain moieties based resin (D) in the portion having the structure CH ₃ (hereinafter also simply referred to as "partial structure of side chain CH _3.") Comprising ethyl, propyl, etc. with the CH ₃ Part of the structure. On the other hand, since a methyl group directly bonded to the main chain of the hydrophobic resin (D) (for example, an α-methyl group having a repeating unit of a methacrylic acid structure) is affected by the main chain, the hydrophobic resin (D) The surface biasing is small and is not included in the CH ₃ partial structure in the present invention.

More specifically, the hydrophobic resin (D) includes, for example, a repeating unit represented by the following general formula (M): a repeating unit derived from a monomer having a polymerizable moiety having a carbon-carbon double bond, that is, In the case where R ₁₁ to R ₁₄ are CH ₃ "by itself", the CH ₃ does not include the CH ₃ moiety structure of the side chain moiety in the present invention. On the other hand, via some of the atoms present from the CC backbone CH ₃ CH ₃ partial structure corresponding to the partial structure to those of the present invention. For example, in the case where R ₁₁ is ethyl (CH ₂ CH ₃ ), it is assumed to have "one" CH ₃ partial structure in the present invention.

[Chemical Formula 12]

In the above formula (M), R ₁₁ to R ₁₄ each independently represent a side chain moiety. Examples of R ₁₁ to R ₁₄ as a side chain moiety include a hydrogen atom and a monovalent organic group. Examples of the monovalent organic group of R ₁₁ to R ₁₄ include an alkyl group, a cycloalkyl group, an aryl group, an alkoxycarbonyl group, a cycloalkoxycarbonyl group, an aryloxycarbonyl group, an alkylaminocarbonyl group, and a cycloalkylamine. These groups may further have a substituent, such as a carbonyl group, an arylaminocarbonyl group or the like.

The hydrophobic resin (D) is preferably a resin containing a repeating unit having a CH ₃ moiety structure in a side chain moiety, and as such a repeating unit, it has a paragraph <0298> to <0321> of JP-A-2014-202969. The repeating unit (x) described in the above is more preferable.

Further, the hydrophobic resin (D) may have at least one selected even when (ii) contains a CH ₃ partial structure in the side chain portion even when (i) a fluorine atom and/or a ruthenium atom is contained. A group in the group of (x) to (z) below. (x) an acid group (y) having a lactone structure, an acid anhydride group or a hydrazide imine group (z) which is decomposed by the action of an acid

Examples of the acid group (x) include a phenolic hydroxyl group, a carboxylic acid group, a fluorinated alcohol group, a sulfonic acid group, a sulfonylamino group, a sulfonimide group, and an (alkylsulfonyl) (alkylcarbonyl) group. (Alkylsulfonyl)(alkylcarbonyl)indenylene, bis(alkylcarbonyl)methylene, bis(alkylcarbonyl)indenylene, bis(alkylsulfonyl)methylene, double (Alkylsulfonyl) fluorenylene, tris(alkylcarbonyl)methylene, tris(alkylsulfonyl)methylene, and the like. Preferred examples of the acid group include a fluorinated alcohol group (preferably hexafluoroisopropanol), a sulfonium sulfonate group, and a bis(alkylcarbonyl)methylene group.

As the repeating unit having an acid group (x), a repeating unit in which an acid group is directly bonded to a main chain of a resin such as a repeating unit derived from acrylic acid or methacrylic acid, or a resin in a resin via a linking group may be mentioned. In the main chain, a repeating unit such as an acid group is bonded, and further, a polymerization initiator or a chain transfer agent having an acid group may be introduced into the end of the polymer chain during polymerization, which is preferable in any case. The repeating unit having an acid group (x) may contain at least any one of a fluorine atom and a halogen atom. The content of the repeating unit having an acid group (x) is preferably from 1 to 50 mol%, more preferably from 3 to 35 mol%, more preferably from 5 to 20 mol%, based on the total repeating unit in the hydrophobic resin (D). % is further preferred. Specific examples of the repeating unit having an acid group (x) include the repeating unit described in paragraphs <0447> to <0448> of JP-A-2014-235179, but the present invention is not limited thereto.

As the group having a lactone structure, an acid anhydride group or an acid sulfonimide group (y), a group having a lactone structure is particularly preferable. The repeating unit containing these groups is, for example, a repeating unit composed of an acrylate and a methacrylate, and the like is a repeating unit in which the group is directly bonded to the main chain of the resin. Alternatively, the repeating unit may be a repeating unit in which the group is bonded to the main chain of the resin via a linking group. Alternatively, the repeating unit may be introduced to the end of the resin by polymerization using a polymerization initiator or a chain transfer agent having the group. The repeating unit having a group having a lactone structure may, for example, be the same as the repeating unit having a lactone structure described above in the resin (A).

The content of the repeating unit containing a group having a lactone structure, an acid anhydride group or an acid sulfonium imino group is preferably from 1 to 100 mol% based on the total repeating unit in the hydrophobic resin (D), and is preferably from 3 to 100 mol%. 98% Mo is more preferably, and 5 to 95 mol% is further preferred.

The repeating unit having a group (z) decomposed by the action of an acid in the hydrophobic resin (D) may be the same as the repeating unit having an acid-decomposable group exemplified in the resin (A). The repeating unit having a group (z) decomposed by the action of an acid may have at least one of a fluorine atom and a ruthenium atom. The content of the repeating unit having a group (z) decomposed by the action of an acid in the hydrophobic resin (D) is preferably from 1 to 80 mol% based on the total repeating unit in the resin (D), and 10 to 10 More preferably, 80% by mole, and 20% to 60% by mole is further preferred. The hydrophobic resin (D) may further have a repeating unit different from the above repeating unit.

The repeating unit containing a fluorine atom is preferably from 10 to 100 mol%, more preferably from 30 to 100 mol%, based on the total repeating unit contained in the hydrophobic resin (D). Further, the repeating unit containing a ruthenium atom is preferably from 10 to 100 mol%, more preferably from 20 to 100 mol%, based on the total repeating unit contained in the hydrophobic resin (D).

On the other hand, in particular, when the hydrophobic resin (D) contains a CH ₃ partial structure in a side chain portion, the hydrophobic resin (D) preferably has no fluorine atom or a ruthenium atom. Further, the hydrophobic resin (D) preferably contains only a repeating unit composed only of atoms selected from a carbon atom, an oxygen atom, a hydrogen atom, a nitrogen atom and a sulfur atom.

The standard polystyrene-equivalent weight average molecular weight of the hydrophobic resin (D) is preferably from 1,000 to 100,000, more preferably from 1,000 to 50,000. Further, the hydrophobic resin (D) may be used alone or in combination of plural kinds. The content of the composition of the hydrophobic resin (D) is preferably 0.01 to 10% by mass based on the total solid content of the first resist composition, and more preferably 0.05 to 8% by mass.

The residual monomer or oligomer component of the hydrophobic resin (D) is preferably from 0.01 to 5% by mass, more preferably from 0.01 to 3% by mass. Further, the molecular weight distribution (also referred to as "Mw/Mn" or "dispersion degree") is preferably in the range of 1 to 5, and more preferably in the range of 1 to 3.

The hydrophobic resin (D) can also be synthesized by various methods (for example, radical polymerization) by using various commercially available products.

[4] Acid Diffusion Control Agent The first resist composition preferably contains an acid diffusion controlling agent. The acid diffusion control agent functions as a quencher that suppresses the reaction of the acid-decomposable resin in the unexposed portion due to excessive acid generation, as an acid generated from an acid generator or the like during the capture exposure. As the acid diffusion controlling agent, a basic compound, a low molecular compound having a nitrogen atom and having a group desorbed by an action of an acid, and a basic compound which is reduced or eliminated by irradiation by actinic rays or radiation can be used. Or a relatively weak acid bismuth salt relative to the acid generator.

As the basic compound, a compound having a structure represented by the following formulas (A) to (E) can be preferably used.

[Chemical Formula 13]

In the general formulae (A) and (E), R ²⁰⁰ , R ²⁰¹ and R ²⁰² may be the same or different, and represent a hydrogen atom, an alkyl group (preferably having 1 to 20 carbon atoms), and a cycloalkyl group (carbon atom). The number 3 to 20 is preferably a) or an aryl group (having 6 to 20 carbon atoms), and R ²⁰¹ and R ²⁰² may be bonded to each other to form a ring. R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different and each represent an alkyl group having 1 to 20 carbon atoms.

The alkyl group is preferably an alkyl group having a substituent, an aminoalkyl group having 1 to 20 carbon atoms, a hydroxyalkyl group having 1 to 20 carbon atoms or a cyanoalkyl group having 1 to 20 carbon atoms. . It is more preferred that the alkyl groups in the general formulae (A) and (E) are unsubstituted.

Preferred examples of the compound include hydrazine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminomorpholine, aminoalkylmorpholine, and piperidine. Further preferred compounds include exemplified a compound having an imidazole structure, a diazabicyclo structure, a hydrazine hydroxy structure, a hydrazine carboxylate structure, a trialkylamine structure, an aniline structure or a pyridine structure, an alkylamine derivative having a hydroxyl group and/or an ether bond, having a hydroxyl group And/or an aniline derivative of an ether bond, and the like. Specific examples of preferred compounds include the compounds exemplified in US 2012/0219913 A1 <0379>. Further, as a preferred basic compound, an amine compound having a phenoxy group, an ammonium salt compound having a phenoxy group, an amine compound having a sulfonate group, and an ammonium salt compound having a sulfonate group can be further exemplified. These basic compounds may be used alone or in combination of two or more.

The first resist composition may contain a basic compound or may not contain a basic compound. However, when a basic compound is contained, the content of the basic compound is usually 0.001 to 10 based on the solid content of the composition. The mass% is preferably 0.01 to 5% by mass. The ratio of the acid generator to the basic compound to be used in the composition is preferably an acid generator/basic compound (mole ratio) = 2.5 to 300, more preferably 5.0 to 200, still more preferably 7.0 to 150.

A low molecular compound having a nitrogen atom and having a group desorbed by the action of an acid (hereinafter, also referred to as "compound (C)") is an amine derivative having a group desorbed by an action of an acid on a nitrogen atom. The object is preferred. As the group desorbed by the action of an acid, an acetal group, a carbonate group, a urethane group, a tertiary ester group, a tertiary hydroxyl group, a half amine acetal group is preferred, and a urethane group is preferred. The semiamine acetal ether group is particularly preferred. The compound (C) preferably has a molecular weight of from 100 to 1,000, more preferably from 100 to 700, and particularly preferably from 100 to 500. The compound (C) may also have a urethane group having a protective group on a nitrogen atom. The protective group constituting the urethane group can be represented by the following formula (d-1).

[Chemical Formula 14]

In the formula (d-1), R _b each independently represents a hydrogen atom, an alkyl group (preferably having 1 to 10 carbon atoms), a cycloalkyl group (preferably having 3 to 30 carbon atoms), and an aryl group ( The number of carbon atoms is preferably from 3 to 30, the aralkyl group (preferably having 1 to 10 carbon atoms) or the alkoxyalkyl group (preferably having 1 to 10 carbon atoms). R _b may also be bonded to each other to form a ring. The alkyl group, cycloalkyl group, aryl group or aralkyl group represented by R _b may be a functional group such as a hydroxyl group, a cyano group, an amine group, a pyrrolidinyl group, a piperidinyl group, a morpholinyl group or an oxo group, or an alkoxy group. Substituted by a halogen atom. The alkoxyalkyl group represented by R _b is also the same.

As R _b , a linear or branched alkyl group, a cycloalkyl group or an aryl group is preferred. A linear or branched alkyl group or a cycloalkyl group is more preferred. Examples of the ring in which two R _b are bonded to each other include an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a heterocyclic hydrocarbon group or a derivative thereof. The specific structure of the group represented by the formula (d-1) is exemplified by the structure disclosed in US 2012/0135348 A1 <0466>, but is not limited thereto.

It is particularly preferable that the compound (C) has a structure represented by the following formula (6).

[Chemical Formula 15]

In the formula (6), R _a represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group. When l is 2, two R _a may be the same or different, and two R _a may be bonded to each other to form a heterocyclic ring together with a nitrogen atom in the formula. The heterocyclic ring may also contain a hetero atom other than the nitrogen atom in the formula. The same as R _b in the general formula (d-1) in the meaning of R _b, preferred embodiments are also the same. l represents an integer of 0 to 2, and m represents an integer of 1 to 3, and satisfies l+m=3. In the formula (6), an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group as R _a may be the same as the above-mentioned alkyl group, cycloalkyl group, aryl group or aralkyl group which may be substituted as R _b . The group is replaced by the same group as the group described.

Specific examples of the alkyl group, the cycloalkyl group, the aryl group and the aralkyl group of the above R _a (the alkyl group, the cycloalkyl group, the aryl group and the aralkyl group may be substituted by the above group) may be exemplified. The group of the specific example of R _b in the formula (d-1) is the same. Specific examples of the compound (C) which is particularly preferred in the present invention include the compounds disclosed in US 2012/0135348 A1 <0475>, but are not limited thereto.

The compound represented by the formula (6) can be synthesized in accordance with JP-A-2007-298569, JP-A-2009-199021, and the like. In the present invention, the low molecular compound (C) having a nitrogen atom and having a group desorbed by the action of an acid can be used singly or in combination of two or more. The content of the compound (C) in the first resist composition is preferably 0.001 to 20% by mass based on the total solid content of the composition, more preferably 0.001 to 10% by mass, still more preferably 0.01 to 5% by mass. Preferably.

In the first resist composition, a phosphonium salt having a relatively weak acid relative to the acid generator can be used as the acid diffusion controlling agent. In the case where an acid generator is used in combination with a phosphonium salt which produces an acid which is relatively weakly acidic with respect to an acid produced by an acid generator, an acid produced by an acid generator by irradiation with actinic radiation or radiation has When the unreacted weak acid anion ruthenium salt collides, a weak acid is released by hydrazine exchange to produce a sulfonium salt having a strong acid anion. In this process, the strong acid is replaced with a weak acid having a lower catalytic performance, so that the acid is deactivated in appearance and the acid diffusion can be controlled.

As the onium salt which is relatively weak to the acid generator, a compound represented by the following formulas (d1-1) to (d1-3) is preferred.

[Chemical Formula 16]

In the formula, R ⁵¹ is a hydrocarbon group which may have a substituent, and Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent (wherein a fluorine atom is not substituted in a carbon adjacent to S) And R ⁵² is an organic group, Y ³ is a linear, branched or cyclic alkylene group or an arylene group, Rf is a hydrocarbon group containing a fluorine atom, and M ^{+ is} independently a ruthenium or osmium cation.

Preferable examples of the phosphonium cation or the phosphonium cation represented by M ⁺ include an anthracene cation exemplified by the formula (ZI) and a phosphonium cation exemplified by the formula (ZII).

A preferred example of the anion moiety of the compound represented by the formula (d1-1) is a structure exemplified in the paragraph [0198] of JP-A-2012-242799. A preferred example of the anion moiety of the compound represented by the formula (d1-2) is a structure exemplified in paragraph [0201] of JP-A-2012-242799. Preferred examples of the anion portion of the compound represented by the formula (d1-3) include those exemplified in paragraphs [0209] and [0210] of JP-A-2012-242799.

The sulfonium salt which is relatively weakly acidic with respect to the acid generator may also be (C) a compound having a cation moiety and an anion site in the same molecule, and the cation moiety and the anion site are linked by a covalent bond (hereinafter, also referred to as "a compound" (CA)".). As the compound (CA), a compound represented by any one of the following formulae (C-1) to (C-3) is preferred.

[Chemical Formula 17]

In the general formulae (C-1) to (C-3), R ₁ , R ₂ and R _{3 each} represent a substituent having 1 or more carbon atoms. L ₁ represents a divalent linking group or a single bond linking the cation moiety to the anion site. -X ^- represents an anion moiety selected from the group consisting of -COO ^- , -SO ₃ ^- , -SO ₂ ^- , -N ^- -R ₄ . R ₄ represents a carbonyl group at a point of attachment to an adjacent N atom: -C(=O)-, sulfonyl group: -S(=O) ₂ -, sulfinyl group: -S(=O)- A monovalent substituent. R ₁ , R ₂ , R ₃ , R ₄ and L ₁ may be bonded to each other to form a ring structure. Further, in (C-3), two of R ₁ to R ₃ may be combined to form an N atom and a double bond.

Examples of the substituent having 1 or more carbon atoms in R ₁ to R ₃ include an alkyl group, a cycloalkyl group, an aryl group, an alkoxycarbonyl group, a cycloalkoxycarbonyl group, an aryloxycarbonyl group, and an alkylaminocarbonyl group. And a cycloalkylaminocarbonyl group, an arylaminocarbonyl group, or the like. Alkyl groups, cycloalkyl groups, and aryl groups are preferred.

The L ₁ which is a divalent linking group may, for example, be a linear or branched alkylene group, a cycloalkylene group, an arylene group, a carbonyl group, an ether bond, an ester bond, a guanamine bond, a urethane bond, or a urea. A prime bond or a group obtained by combining these two or more kinds. L ₁ is an alkylene group, an arylene group, an ether bond, an ester bond, and a group obtained by combining the two or more kinds thereof is more preferable. Preferred examples of the compound represented by the formula (C-1) include paragraphs [0037] to [0039] of JP-A-2013-6827 and paragraph [0027] of JP-A-2013-8020. The compound exemplified in [0029]. Preferred examples of the compound represented by the formula (C-2) include the compounds exemplified in paragraphs [0012] to [0013] of JP-A-2012-189977. Preferred examples of the compound represented by the formula (C-3) include the compounds exemplified in paragraphs [0029] to [0031] of JP-A-2012-252124.

The content of the cerium salt relative to the weak acid of the acid generator is preferably 0.5 to 10.0% by mass, more preferably 0.5 to 8.0% by mass, even more preferably 1.0 to 8.0% by mass, based on the solid content of the composition.

[5] Solvent The first resist composition usually contains a solvent. Examples of the solvent which can be used in the preparation of the composition include an alkylene glycol monoalkyl ether carboxylate, an alkylene glycol monoalkyl ether, an alkyl lactate, and an alkoxypropionic acid alkyl group. An ester or a cyclic lactone (preferably having 4 to 10 carbon atoms), a monoketone compound having a ring (preferably having 4 to 10 carbon atoms), an alkylene carbonate or an alkoxyacetic acid alkyl group. An organic solvent such as an ester or an alkyl pyruvate. Specific examples of such solvents include those described in the specification of the U.S. Patent Application Publication No. 2008/0187860, <0441> to <0455.

In the present invention, as the organic solvent, a mixed solvent in which a solvent having a hydroxyl group in the structure and a solvent having no hydroxyl group in the structure are mixed may be used. The solvent containing a hydroxyl group and the solvent containing no hydroxyl group can appropriately select the above-exemplified compounds, and a solvent containing a hydroxyl group, an alkylene glycol monoalkyl ether, an alkyl lactate or the like is preferable, and propylene glycol monomethyl ether is preferable. (PGME, the alias 1-methoxy-2-propanol), ethyl lactate, and methyl 2-hydroxyisobutyrate are more preferred. Further, as a solvent containing no hydroxyl group, an alkylene glycol monoalkyl ether acetate, an alkyl alkoxy propionate, a monoketone compound which may contain a ring, a cyclic lactone, an alkyl acetate or the like is Preferably, among these, propylene glycol monomethyl ether acetate (PGMEA, alias 1-methoxy-2-ethoxypropane propane), ethyl ethoxypropionate, 2-heptanone, γ-butane Ester, cyclohexanone, and butyl acetate are particularly preferred, and propylene glycol monomethyl ether acetate, ethyl ethoxy propionate, and 2-heptanone are preferred. The mixing ratio (mass) of the solvent containing a hydroxyl group and the solvent containing no hydroxyl group is 1/99 to 99/1, preferably 10/90 to 90/10, and more preferably 20/80 to 60/40. In terms of coating uniformity, a mixed solvent containing 50% by mass or more of a solvent containing no hydroxyl group is particularly preferable. The solvent preferably contains propylene glycol monomethyl ether acetate, and a mixed solvent of two or more kinds of propylene glycol monomethyl ether acetate alone solvent or propylene glycol monomethyl ether acetate is preferable.

[6] Surfactant The first resist composition may further contain a surfactant or may not contain the surfactant, and in the case of a surfactant, a fluorine-containing and/or a terpene-based surfactant (fluorine) Any one or two or more kinds of a surfactant, a quinone surfactant, and a surfactant having both a fluorine atom and a ruthenium atom are more preferable.

When the first resist composition contains a surfactant, when an exposure light source of 250 nm or less, particularly 220 nm or less is used, it is possible to provide a resist pattern having less adhesion and development defects with good sensitivity and resolution. The surfactant described in the paragraph <0276> of the specification of the US Patent Application Publication No. 2008/0248425 is exemplified as the fluorine-based and/or quinone-based surfactant. Further, in the present invention, other surfactants than the fluorine-based and/or quinone-based surfactants described in paragraph <0280> of the specification of US Patent Application Publication No. 2008/0248425 can also be used.

These surfactants may be used singly or in combination of several kinds. When the first resist composition contains a surfactant, the amount of the surfactant used is preferably 0.0001 to 2% by mass based on the total solid content of the composition, and more preferably 0.0005 to 1% by mass. On the other hand, when the amount of the surfactant added is 10 ppm or less based on the total amount of the composition (excluding the solvent), the surface property of the hydrophobic resin is improved, whereby the surface of the resist film can be made. Further, it has hydrophobicity and can improve water followability during immersion exposure.

[7] Other Additives The first resist composition may contain a cerium carboxylate salt or may not contain a cerium carboxylate salt. The carboxylic acid cerium salt can be described in the specification of the US Patent Application Publication No. 2008/0187860, <0605> to <0606>. The cerium carboxylate salts can be synthesized by reacting cerium hydroxide, cerium hydroxide, ammonium hydroxide, and carboxylic acid with silver oxide in a suitable solvent.

When the first resist composition contains a cerium carboxylate salt, the content thereof is usually 0.1 to 20% by mass, preferably 0.5 to 10% by mass, and preferably 1 to 7% by mass based on the total solid content of the composition. It is further preferred. The first resist composition can further contain an acid multiplier, a dye, a plasticizer, a photosensitizer, a light absorber, an alkali-soluble resin, a dissolution inhibitor, and a compound which promotes solubility with respect to a developer, as needed (for example) A phenol compound having a molecular weight of 1,000 or less, an alicyclic group having a carboxyl group, or an aliphatic compound).

For the phenol compound having a molecular weight of 1,000 or less, for example, the method described in JP-A No. 4-122938, JP-A No. 2-28531, U.S. Patent No. 4,916,210, European Patent No. 219,294, etc. Technicians easily synthesize. Specific examples of the alicyclic or aliphatic compound having a carboxyl group include a carboxylic acid derivative having a steroid structure such as cholic acid, deoxycholic acid or lithocholic acid, an adamantanecarboxylic acid derivative, and an adamantane dicarboxylic acid. And cyclohexanecarboxylic acid, cyclohexanedicarboxylic acid, etc., but it is not limited to these.

The solid content concentration of the first resist composition is usually 1.0 to 10% by mass, preferably 2.0 to 5.7 % by mass, more preferably 2.0 to 5.3 % by mass. By setting the solid content concentration to the above range, the resist solution can be uniformly applied onto the substrate, and a resist pattern having excellent line width roughness can be formed. Though the reason for this is not clear, the reason may be that the solid content concentration is preferably 10% by mass or less, preferably 5.7% by mass or less, whereby the raw material, particularly the photoacid generator, can be suppressed in the resist solvent. The aggregation in the middle results in the formation of a uniform resist film. The solid content concentration means the mass percentage of the mass of the resist component other than the solvent with respect to the total mass of the composition.

The method for preparing the first resist composition is not particularly limited, and it is preferred to dissolve the above components in a predetermined organic solvent, and the mixed solvent is preferably filtered by a filter. The filter for filter filtration has a pore size of 0.1 μm or less, more preferably 0.05 μm or less, and a polytetrafluoroethylene, polyethylene or nylon which is preferably 0.03 μm or less. In the case of filter filtration, for example, it is also possible to carry out cyclic filtration by connecting a plurality of filters in series or in parallel, or to perform filtration, for example, in JP-A-2002-62667. Further, the composition may be subjected to plural filtration. Further, the composition may be subjected to a degassing treatment or the like before and after the filter is filtered.

The first resist composition relates to a sensitized ray- or radiation-sensitive resin composition in which the properties are changed by reaction with actinic rays or radiation. More specifically, the present invention relates to a semiconductor manufacturing process such as an IC, a circuit substrate such as a liquid crystal or a thermal induction head, a mold structure for imprinting, and other photo-etching steps, a lithographic printing plate, and an acid-curable composition. A sensitizing ray-sensitive or radiation-sensitive resin composition used in the present invention.

<Second Resist Composition> Next, a second resist composition used in the pattern forming method of the present invention will be described. The second resist composition may be a negative resist composition or a positive resist composition, and each of the known resist compositions may be used, but for the above reasons, the negative resist composition The material (more specifically, a negative resist composition for developing an organic solvent) is preferred. Also, the second resist composition is typically a chemically amplified resist composition.

As described above, the second resist composition preferably contains a resin which is increased in polarity by the action of an acid and which has a reduced solubility with respect to the developer containing the organic solvent. As such a resin, the same as the resin which is increased in polarity by the action of an acid and which has a reduced solubility with respect to the developer containing an organic solvent, which is described in the first resist composition, may be mentioned. The preferred range of the content of the above resin in the total amount of the two resist compositions is also the same as that described in the first resist composition. Further, the second resist composition can similarly contain the above-described respective components which can be contained in the first resist composition, and the preferable range of the content of each component with respect to the total amount of the second resist composition is also It is the same as that described in the first resist composition.

Various materials used in the organic pattern embedding composition of the present invention and the pattern forming method of the present invention (for example, a solvent, a resist solvent, a developing solution, a rinsing liquid, or an organic solvent contained in the organic pattern embedding composition) It is preferable that the antireflection film-forming composition, the top coat layer-forming composition, and the like do not contain an impurity such as a metal. The content of the impurities contained in these materials is preferably 1 ppm or less, more preferably 100 ppt or less, still more preferably 10 ppt or less, and substantially no content (below the detection limit of the measuring device) is particularly preferable. As a method of removing impurities such as metals from the above various materials, for example, filtration using a filter can be mentioned. The pore size of the filter is preferably 10 nm or less, more preferably 5 nm or less, and still more preferably 3 nm or less. As a material of the filter, a filter made of polytetrafluoroethylene, polyethylene, or nylon is preferable. The filter can also be used for cleaning with an organic solvent. In the filter filtration step, a plurality of filters may be connected in series or in parallel for use. In the case of using a plurality of filters, a filter having a different aperture and/or material may be combined for use. Moreover, various materials may be subjected to multiple filtrations, and the step of performing multiple filtrations may also be a cyclic filtration step. In addition, as a method of reducing impurities such as metals contained in the above-mentioned various materials, a raw material having a small metal content is selected as a raw material constituting various materials, a filter for filtering various materials is used, and Teflon is used in the apparatus. (registered trademark) A method of performing distillation such as lining under conditions that suppress contaminants as much as possible. The preferred conditions for filter filtration of the raw materials constituting the various materials are the same as those described above. In addition to the filter filtration, impurities may be removed by the adsorbent material, and the filter may be combined with the adsorbent material for use. As the adsorbent, a known adsorbent can be used. For example, an inorganic adsorbent such as tannin or zeolite, or an organic adsorbent such as activated carbon can be used.

Further, the present invention relates to a method of manufacturing an electronic component including the above-described planarization method used in the present invention or the pattern formation method of the present invention, and an electronic component manufactured by the method. The electronic component of the present invention is preferably mounted on an electric or electronic device (home appliance, OA (Office Automation), media related device, optical device, communication device, etc.). [Examples]

Hereinafter, the present invention will be described in further detail by way of examples, but the invention is not limited thereto.

<Preparation of Resist Composition> The components shown in the following Table 1 were dissolved in PGMEA (propylene glycol monomethyl ether acetate) and PGME (propylene glycol monomethyl ether) at a concentration of 6.0 wt% solid content (70 wt%). %/30 wt%) The obtained solution was filtered with a polyethylene filter having a pore size of 0.03 μm to obtain a resist composition (organic pattern embedding composition) having a solid concentration of 6.0 wt%. Further, in Table 1, the number 値 described in the column of the structure of the resin (A) indicates the composition ratio (mol ratio) of each repeating unit.

[Table 1] <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Table 1 </td><td> Resin (A) </td> <td> Acid generator</td><td> Basic compound</td></tr><tr><td> Structure</td><td><img wi="129" he="78" File="IMG-2/Draw/02_image034.jpg" img-format="jpg"></img> 40/60 </td><td><img wi="157" he="82" file=" IMG-2/Draw/02_image034.jpg" img-format="jpg"></img></td><td><img wi="139" he="81" file="IMG-2/Draw/ 02_image034.jpg" img-format="jpg"></img></td></tr><tr><td> Concentration in total solids</td><td> 88.5wt% </td>< Td> 10.0wt% </td><td> 1.5wt% </td></tr></TBODY></TABLE>

<Synthesis of Resin (Resin for Buried)> 73.9 g of PGME was placed in a three-necked flask under a nitrogen stream, and heated to 80 °C. 10.2 g of BMB (structure described below), 16.0 g of DiOH (structure described below), 11.1 g of PME-200 (structure described below), and a polymerization initiator V-601 (Wako Pure Chemical Industries) were added dropwise thereto over 6 hours. , manufactured by Ltd., a solution obtained by dissolving 137.3 g of PGME in 4 mol% with respect to the monomer. The solution after the dropwise addition was further stirred at 80 ° C for 2 hours. After the stirred solution was cooled, it was added dropwise to a mixture of 1217.8 g of heptane and 521.9 g of ethyl acetate over 20 minutes. The precipitated powder was collected by filtration and dried to obtain 33.7 g of the resin (embedded resin) of the following A-1. The composition ratio (molar ratio) of the repeating unit of the obtained resin was 30/50/20, the weight average molecular weight was 26,000 in terms of standard polystyrene, and the degree of dispersion (Mw/Mn) was 2.03. Further, the following resins A-2 to A-10 and B-1 to B-6 (resin for embedding) were synthesized by the same operation.

[Chemical Formula 18]

<Preparation of Organic Pattern Buried Compositions (Examples 1 to 21 and Comparative Examples 1 to 6)> The obtained resin for embedding was obtained as a solid content concentration (5.0 wt% or 2.5 wt%) shown in Table 2. This was dissolved in a solvent shown in the following Table 2, and this was filtered with a polyethylene filter having a pore size of 0.03 μm to prepare an organic pattern embedding composition having a solid concentration of 5.0% by weight or 2.5% by weight.

<Evaluation> (Embedded property) The organic anti-reflection film-forming composition ARC29A (manufactured by Brewer Science, Inc.) was applied onto a ruthenium wafer to form an organic anti-reflection film having a film thickness of 86 nm. The prepared resist composition was applied onto an organic anti-reflection film, and baked (Pre Bake; PB) at a temperature of 100 ° C for 60 seconds to form a resist film having a film thickness of 200 nm. The obtained resist film was subjected to pattern exposure using an ArF excimer laser scanner (NA (opening number) 0.75) through a 6% halftone mask having a pitch of 150 nm and a light-shielding width of 75 nm. The resist film after the pattern exposure was baked at a temperature of 115 ° C for 60 seconds, and then developed by stirring with a butyl acetate developing solution for 30 seconds to obtain a line portion of 90 nm. A line and space pattern of 60 nm in the space portion. Next, the obtained pattern was baked at a temperature of 200 ° C for 60 seconds, and the prepared organic pattern embedding composition was applied onto the pattern to form a planarizing film (planarizing layer). The cross section of the formed planarizing film was confirmed by SEM (scanning electron microscope), and the embedding property was evaluated based on the following evaluation criteria. <Evaluation Criteria> A (excellent): No void was observed. B (slightly excellent): When the void is observed, the ratio of the area of the void in the image is 5% or less. C (slightly poor): When the void is seen, the proportion of the area of the void in the image is more than 5% and less than 10%. D (poor): When the gap is seen, the proportion of the area of the gap in the image is greater than 10%. The results are shown in Table 2.

(Flatness) An organic anti-reflection film is formed on the germanium wafer by the same method as the above evaluation of embedding, and a resist film is formed on the organic anti-reflection film. The obtained resist film was subjected to pattern exposure using an ArF excimer laser scanner (NA0.75) through a 6% halftone mask having a pitch of 600 nm and a light-shielding portion of 300 nm. The resist film after the pattern exposure was baked at a temperature of 150 ° C for 60 seconds, and then developed by stirring with a butyl acetate developing solution for 30 seconds to obtain a line having a line portion of 300 nm and a space portion of 300 nm. Space pattern. Next, the obtained pattern was baked at a temperature of 200 ° C for 60 seconds, and the prepared organic pattern-embedded composition was applied onto the pattern to form a planarizing film (planarizing layer). The difference in film thickness between the line portion and the space portion after forming the planarizing film was observed by an atomic force micromirror, and the difference between the maximum film thickness and the minimum film thickness (that is, the difference in film thickness between the line portion and the space portion) was calculated, and the evaluation was based on the following evaluation. Benchmark evaluation flatness. <Evaluation Criteria> A (very excellent): The difference in film thickness between the line portion and the space portion is less than 5 nm. B (excellent): The difference in film thickness between the line portion and the space portion is 5 nm or more and less than 10 nm. C (slightly excellent): The difference in film thickness between the line portion and the space portion is 10 nm or more and less than 15 nm. D (difference): The difference in film thickness between the line portion and the space portion is 15 nm or more. The results are shown in Table 2.

(Etching Rate) The prepared organic pattern embedding composition was applied onto a tantalum wafer, and baked at 150 ° C for 60 seconds to form a planarizing film (planarizing layer). The obtained film was subjected to an etching treatment for 5 seconds with oxygen, and the etching rate was calculated from the change in film thickness before and after the treatment. The results are shown in Table 2. The greater the etching rate, the more excellent the etching property. In practical terms, an etching rate of 100 Å (Ångström) / sec or more is preferable.

<Formation of Pattern> A line and space pattern (first pattern) is formed by the same method as the above evaluation of embedding, and a planarization film is formed on the line and space pattern. Further using the same resist composition (second resist composition) as the resist composition (first resist composition) used in the formation of the first pattern, by the first pattern In the same manner, a resist film (second resist film) is formed on the planarization film, and then exposure and development are performed to form a line and space pattern (second pattern).

[Table 2]

In Table 2, the structure of the resin used was as follows. Further, the number 化学 of the chemical formulas simultaneously described in A-1 to A-10, A-13, and B-1 to B-5 indicates the composition ratio (mol ratio) of each repeating unit. Further, n described in A-12 and A-14 to A-17 indicates the number of repeating units. Further, Table 3 below shows the number of carbon atoms, the number of oxygen atoms, and the R2 hetero atom ratio in R ₂ of each repeating unit of A-1 to A-10.

[Chemical Formula 19]

[table 3]

The large West parameter in Table 2 indicates the Great West parameter of each of the resins (A-1 to A-21, B-1 to B-6). The calculation method of the Daxi parameter is as described above.

Tg in Table 2 represents the glass transition temperature Tg of each of the resins (A-1 to A-21, B-1 to B-6). The measurement method of Tg is as described above.

In Table 2, the details of the solvent used are as follows.・CyHx: cyclohexanone ・MEK: methyl ethyl ketone ・MeOH: methanol ・PGME: propylene glycol monomethyl ether

As is clear from Table 2, Examples 1 to 21 containing a resin (specific resin) having a large West parameter of more than 5.0 exhibited excellent embedding property, flatness, and etching property. According to the comparison of Examples 1 to 10 in which the specific resin has a repeating unit represented by the above formula (1-1), the repeating unit represented by the above formula (1-1) (R ₂ : a group represented by the formula (P)) Examples 1 to 2 and 4 to 7 of the group showed more excellent embedding property and flatness. In addition, Examples 1 to 2, 4, and 6 to 7 in which the ratio of the repeating unit (R ₂ : group represented by the formula (P)) represented by the above formula (1-1) is 15 mol% or more shows that it is more excellent. Etchability. Wherein the sum of a repeating unit represented by the formula (1-1) R ₂ is different from the repeating unit having a group represented by the formula (P), the repeating unit represented by the formula (1-1) R ₂ Examples 1 and 2 which are repeating units of a group having two or more hydroxyl groups exhibited further excellent etching properties. According to the comparison of Examples 14 to 17 in which the specific resin contained only the repeating unit (X: -O-) represented by the above formula (1-2), Examples 15 to 17 in which the weight average molecular weight of the specific resin was 8,000 or less showed More excellent etchability. Among them, Examples 16 to 17 in which the weight average molecular weight of the specific resin was 5,000 or less showed further excellent etching properties. Among them, Example 17 in which the weight average molecular weight of the specific resin was 2,000 or less exhibited more excellent embedding property, flatness, and etching property.

On the other hand, in Comparative Examples 1 to 6 which did not contain a resin having a large West parameter of more than 5.0, at least one of embedding property, flatness, and etching property was insufficient.

51‧‧‧Substrate
52‧‧‧First resist film
53‧‧‧The first resist film to be exposed
54‧‧‧ first pattern
55‧‧‧Micronized pattern
56‧‧‧Second resist film
57‧‧‧Fixed second resist film
58‧‧‧second pattern
61‧‧‧ mask
71‧‧‧Acradiation rays or radiation
75‧‧‧etching gas
81‧‧‧flattening layer

1(a) to 1(i) are schematic cross-sectional views for explaining an embodiment of a planarization method and a pattern forming method used in the present invention.

51‧‧‧Substrate

52‧‧‧First resist film

53‧‧‧The first resist film to be exposed

54‧‧‧ first pattern

55‧‧‧Micronized pattern

56‧‧‧Second resist film

57‧‧‧Fixed second resist film

58‧‧‧second pattern

61‧‧‧ mask

71‧‧‧Acradiation rays or radiation

75‧‧‧etching gas

81‧‧‧flattening layer

Claims (9)

An organic pattern embedding composition containing a resin having a large West parameter greater than 5.0. The organic pattern embedding composition according to claim 1, wherein the resin is at least one selected from the group consisting of poly(meth)acrylate resins, polyester resins, and polyether resins. Resin. The organic pattern embedding composition according to the first aspect of the invention, wherein the resin has a repeating unit represented by the following formula (1-1), [Chemical Formula 1] In the formula (1-1), R ₁ represents a hydrogen atom or an organic group; R ₂ represents a hydrocarbon group having hetero atoms; wherein the number of hetero atoms in R ₂ with respect to the ratio of the number of carbon atoms in R ₂ is 0.30 or more. The organic pattern embedding composition according to the third aspect of the invention, wherein, in the formula (1-1), R ₂ is a group containing a lactone structure, a group containing a carbonate structure, and a group B a group having an acetal structure, a group having a hydroxyl group, or a group represented by the following formula (P), [Chemical Formula 2] In the formula (P), R _A represents a divalent hydrocarbon group; R _B represents a monovalent hydrocarbon group; n represents an integer of 1 or more; and when n is an integer of 2 or more, a plurality of R _A may be the same or different; Bonding position. The organic pattern embedding composition according to the first aspect of the invention, wherein the resin has a repeating unit represented by the following formula (1-2), [Chemical Formula 3] In the formula (1-2), L represents a divalent hydrocarbon group; and X represents -O-, -S- or -CO-O-. The organic pattern embedding composition according to any one of claims 1 to 5, wherein the resin does not contain an aromatic ring. A pattern forming method, comprising the steps of: forming a first resist film on a substrate using a first resist composition; exposing the first resist film; and exposing The first resist film is developed to form a first pattern, and the organic pattern embedding composition according to any one of claims 1 to 6 is used in a substrate provided with the first pattern. a step of forming a planarization layer; a step of forming a second resist film on the planarization layer using a second resist composition; a step of exposing the second resist film; and exposing The foregoing second resist film is developed to form a second pattern. The pattern forming method according to claim 7, wherein the first pattern and/or the second pattern are patterns formed by development using a developing solution containing an organic solvent. A method of manufacturing an electronic component, comprising the pattern forming method of claim 7 or 8.