TW202136917A - Treatment solution, pattern-forming method - Google Patents

Abstract

The present invention provides a treatment fluid that offers superior resolution and resist loss inhibition, as well as superior residue inhibition, when used to develop and/or wash (rinse) a resist, as well as a patterning method pertaining to said treatment fluid. The treatment fluid of the present invention is a resist patterning treatment fluid that is used for post-exposure developing and/or washing of a resist obtained from an actinic-light- or radiation-sensitive composition, the fluid containing a first organic solvent and a second organic solvent. The first organic solvent includes at least one type of solvent selected from the group consisting of C8-10 ketone solvents, C8-10 ester solvents other that acetate esters, and C8-10 aromatic hydrocarbon solvents. The second organic solvent includes at least one type of solvent selected from the group consisting of C5-7 ketone solvents and C5-7 ester solvents other than acetate esters.

Description

Treatment liquid, pattern forming method

The present invention relates to a treatment liquid for patterning resist film and a pattern forming method. In more detail, the present invention relates to a processing liquid used in semiconductor manufacturing processes such as IC (Integrated Circuit), circuit substrates such as liquid crystals and thermal heads, and other photolithographic processes in photosensitive etching processing. And pattern forming method.

In the past, in the manufacturing process of semiconductor components such as IC and LSI (Large Scale Integrated Circuit), microfabrication was performed by using photoresist composition lithography. In recent years, with the increasing integration of integrated circuits, it is required to form ultra-fine patterns in the sub-micron area and the quarter-micron area. Along with this, the exposure wavelength also shows a tendency to shorten the wavelength, such as from g-ray to i-ray, and further to KrF excimer laser light. Furthermore, in addition to excimer laser light, lithography using electron beam, X-ray or EUV light (Extreme Ultra Violet) is also being developed. In this kind of lithography, after forming a film (resist film) by sensitizing rays or a radiation-sensitive composition (also called a resist composition), the obtained film is developed or used by a developer The rinsing solution cleans the developed film. For example, Patent Document 1 discloses a rinse liquid containing two or more organic solvents having a predetermined SP value.

[Patent Document 1] Japanese Patent Application Publication No. 2018-081306

In recent years, with the increasing integration of integrated circuits, it is required to use resist compositions to form fine patterns (high-resolution patterns). In the process of forming such a fine pattern, the distance between the patterns becomes narrow along with the miniaturization, thereby generating a strong capillary force and there is a problem that it is difficult to form a high-quality pattern. Hereinafter, excellent resolution means that a high-quality pattern can be formed. Furthermore, since the film thickness of the pattern also tends to become thinner with the miniaturization, it is more remarkably required than before to eliminate the reduction in the performance of the pattern caused by the "thinning of the pattern" during the development process and the rinsing process. That is, there is a demand for a treatment solution (developer and/or rinse solution) that can simultaneously eliminate pattern collapse and pattern thinning.

In addition, when the treatment liquid is applied, it is also required to be able to suppress residues on the obtained pattern.

The inventors of the present invention found that when the treatment liquid (mixed solvent of butyl acetate and diisobutyl ketone) specifically disclosed in Patent Document 1 was used, the desired effect could not be obtained.

The present invention was made in view of the above points, and its subject is to provide a treatment solution that, when the treatment solution is used in at least one of the development and cleaning (rinsing) of the resist film, the resolution and the suppression of thinning It has excellent performance and residue inhibition. In addition, the subject of the present invention is to provide a pattern forming method related to the above-mentioned treatment liquid.

As a result of intensive research on the above-mentioned problems, the inventors found that the above-mentioned problems can be solved by the following configuration, and completed the present invention.

(1) A treatment liquid used for at least one of the development and cleaning of a resist film obtained from a sensitizing ray or a radiation-sensitive composition for patterning a resist film , The aforementioned treatment liquid contains: The first organic solvent; and the second organic solvent, The first organic solvent includes one selected from the group consisting of ketone solvents having 8 to 10 carbons, ester solvents having 8 to 10 carbons other than acetate, and aromatic hydrocarbon solvents having 8 to 10 carbons At least one, The second organic solvent includes at least one selected from the group consisting of a ketone solvent having 5 to 7 carbon atoms and an ester solvent having 5 to 7 carbon atoms other than acetate. (2) The treatment liquid according to (1), wherein the first organic solvent is selected from the group consisting of 2,5-dimethyl-3-hexanone, 2-methyl-3-heptanone, 5-methyl- 3-heptanone, diisobutyl ketone, 2,2,4,4-tetramethyl-3-pentanone, dibutyl carbonate, heptyl formate, 2-ethylhexyl formate, isoamyl propionate , Hexyl propionate, butyl butyrate, isobutyl butyrate, butyl isobutyrate, ethyl caproate, propyl caproate, isopropyl caproate, butyl caproate, isobutyl caproate, At least one of the groups of 3,3-dimethylbutane ethyl ester, mesitylene, cumene, 1,2,4,5-tetramethylbenzene and p-cymene . (3) The treatment liquid as described in (1) or (2), wherein the second organic solvent contains selected from the group consisting of 3-methyl-2-butanone, 3,3-dimethyl-2-butanone, 2-methyl-3-pentanone, 3-methyl-2-pentanone, 4-methyl-2-pentanone, diisopropyl ketone, 2-methyl-3-hexanone, 5-methyl -2-hexanone, pentyl formate, isoamyl formate, tertiary amyl formate, hexyl formate, isopropyl propionate, isobutyl propionate, ethyl isobutyrate, diethyl carbonate and dicarbonate At least one of the group of propyl esters. (4) The treatment liquid according to any one of (1) to (3), wherein the first organic solvent and the second organic solvent satisfy the relationship of formula (1). Formula (1): 5.0℃＜bp1-bp2＜100.0℃ bp1: the boiling point of the first organic solvent bp2: the boiling point of the second organic solvent (5) The treatment liquid according to any one of (1) to (4), wherein at least one of the first organic solvent and the second organic solvent has a branched alkyl group. (6) The treatment liquid according to any one of (1) to (5), wherein both of the first organic solvent and the second organic solvent have a branched alkyl group. (7) The treatment liquid according to any one of (1) to (6), wherein the sensitizing radiation or the radiation-sensitive composition contains a resin having a hydroxystyrene-based repeating unit. (8) A pattern forming method, which has: The resist film forming process of using sensitizing rays or radiation-sensitive composition to form resist film; Exposure process for exposing the resist film; and A treatment process for treating the exposed resist film with the treatment liquid described in any one of (1) to (7). (9) A pattern forming method, which has: The resist film forming process of using sensitizing rays or radiation-sensitive composition to form resist film; Exposure process for exposing the resist film; and The process of processing the exposed resist film. In the aforementioned pattern forming method, The processing process has: The developing process of developing with a developing solution; and The washing process of washing with washing liquid, The rinse liquid is the treatment liquid described in any one of (1) to (7). [Effects of the invention]

According to the present invention, it is possible to provide a treatment liquid which, when the above treatment liquid is used for at least one of the development and cleaning (rinsing) of the resist film, has excellent resolution and thinning inhibition and also excellent residue inhibition. Furthermore, according to the present invention, it is possible to provide a pattern forming method related to the above-mentioned treatment liquid.

Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be completed based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

In the label of the group (atomic group) in this specification, as long as it does not violate the purpose of the present invention, the label not labeled with substituted and unsubstituted also includes groups without substituents and groups with substituents. For example, "alkyl" includes not only unsubstituted alkyl (unsubstituted alkyl) but also substituted alkyl (substituted alkyl). In addition, the "organic group" in this specification means a group containing at least one carbon atom.

The "actinic rays" or "radiation rays" in this specification means, for example, the bright line spectrum of mercury lamps, extreme ultraviolet rays represented by excimer lasers, extreme ultraviolet rays (EUV light: Extreme Ultraviolet), X-rays and electron beams ( EB: Electron Beam) and so on. "Light" in this specification means actinic rays or radiation.

Unless otherwise specified, the "exposure" in this manual includes not only exposure using the bright line spectrum of a mercury lamp, extreme ultraviolet, extreme ultraviolet, X-ray and EUV light represented by excimer lasers, but also Delineation performed by particle beams such as electron beams and ion beams.

In this specification, "～" is used in the meaning including the numerical value described before and after it as a lower limit and an upper limit.

Unless otherwise specified, the bonding direction of the divalent groups marked in this specification is not limited. For example, when Y in the compound represented by the general formula "X-Y-Z" is -COO-, Y may be -CO-O- or -O-CO-. In addition, the above-mentioned compound may be "X-CO-O-Z" or "X-O-CO-Z".

In this specification, (meth)acrylate means acrylate and methacrylate, and (meth)acryl means acryl and methacryl.

In this specification, as a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned, for example.

In this specification, the weight average molecular weight (Mw), number average molecular weight (Mn) and degree of dispersion (hereinafter, also referred to as "molecular weight distribution") of the resin (Mw/Mn) are defined as based on GPC (Gel Permeation Chromatography: GPC measurement (solvent: tetrahydrofuran; flow rate (sample injection volume): 10μL; column: TSK gel Multipore HXL-M manufactured by TOSOH CORPORATION; column temperature: 40℃; Flow rate: 1.0mL/min; Detector: Refractive Index Detector (Refractive Index Detector) conversion value of polystyrene.

In this specification, the boiling point means the boiling point at 1 atmosphere.

In this specification, an organic solvent means an organic compound that is liquid at 25°C. The type and content of the organic compound contained in the treatment solution are measured by DI-MS (Direct Injection Mass Chromatography), for example.

[Treatment liquid] The treatment liquid of the present invention is used for at least one of developing and cleaning a resist film obtained from a sensitizing radiation or a radiation-sensitive composition (hereinafter, also referred to as "resist composition"). Treatment liquid for resist film patterning. As a characteristic point of the processing liquid of the present invention, it can be exemplified that it contains a predetermined first organic solvent and a predetermined second organic solvent.

When the resist film is exposed and developed to form a pattern, residues may be generated on the pattern. In order to reduce the generation and/or residue of residues on such patterns, it is effective to use a highly polar organic solvent as a processing liquid (developer and/or rinse liquid). However, on the other hand, high-polarity organic solvents sometimes dissolve the pattern itself and cause the pattern to become thinner. In addition, this kind of high-polarity organic solvent has low volatility in many cases when it exists alone. In particular, it may become a main cause of deterioration of resolution in dense patterns (for example, pattern collapse in dense patterns). The inventors of the present invention conducted further studies based on the above findings and found that by forming a pattern formed by a treatment solution containing a prescribed first organic solvent and a prescribed second organic solvent, the generation and/or residue and thinning of residues are simultaneously suppressed , And can also improve resolution. It is considered that the prescribed first organic solvent suppresses the dissolution or swelling of the pattern and mainly contributes to the improvement of the suppression and resolution of thinning caused by the suppression of the dissolution of the pattern. It is considered that the prescribed second organic solvent mainly contributes to the improvement of residue inhibitory properties.

The inventors of the present invention believe that when a pattern is formed by exposure using EUV light, the use of the treatment liquid of the present invention is particularly significant. Since the wavelength of EUV light (wavelength 13.5nm) is shorter than that of ArF excimer laser light (wavelength 193nm), etc., in the exposure of the resist film, there is a feature that the number of incident photons is small. Therefore, the density in the resist film of the acid generated during EUV exposure tends to be lower than that during ArF exposure. As a method to compensate for this, the resist film applied with EUV exposure has a tendency to increase the content of the photoacid generator compared with the resist film applied with ArF exposure. As a result, when the pattern is formed by EUV exposure, the local solubility of the resist film derived from the photoacid generator is reduced, and residues are likely to be generated. Therefore, by applying the treatment liquid of the present invention that further contains the second organic solvent capable of improving the residue inhibitory property, even when the pattern is formed by EUV exposure, it is easy to obtain a pattern in which the amount of residue is suppressed.

In addition, in the above-mentioned treatment liquid, as the second organic solvent, it is preferable to select an organic solvent with a lower boiling point than the first organic solvent. For example, the first organic solvent and the second organic solvent satisfy the following formula (1): Better. When the boiling point of the second organic solvent is lower than that of the first organic solvent, the second organic solvent volatilizes preferentially when the treatment (for example, rinsing treatment) based on the treatment liquid is followed by drying, and the first organic solvent on the pattern formed The concentration increases. As a result, the effect of the first organic solvent is maximized, and in particular, the effect of suppressing pattern collapse in the dense pattern becomes more remarkable. Hereinafter, it is also referred to as the excellent effect of the present invention that at least one or more of the resolving properties, the thinning inhibitory properties, and the residue inhibitory properties are excellent.

The first organic solvent and the second organic solvent contained in the treatment liquid of the present invention will be described in detail below.

〔The first organic solvent〕 The treatment liquid of the present invention contains a predetermined first organic solvent. The first organic solvent is selected from the group consisting of ketone solvents having 8 to 10 carbons, ester solvents having 8 to 10 carbons other than acetate, and aromatic hydrocarbon solvents having 8 to 10 carbons At least 1 kind of solvent.

<A ketone solvent having 8 to 10 carbon atoms (hereinafter, also referred to as "the first ketone solvent")> As the first organic solvent, the first ketone-based solvent has a carbon number of 8 to 10, and from the viewpoint that at least one of resolution, thinning inhibition, and residue inhibition is better (hereinafter, also referred to simply as "the present invention The point of view that the effect is more excellent".) Considering that 9-10 is preferable.

Examples of the first ketone solvent include 2,5-dimethyl-3-hexanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, and diisobutyl ketone. And, 2,2,4,4-tetramethyl-3-pentanone. Among them, from the viewpoint that the effect of the present invention is more excellent, as the first ketone solvent, 2-methyl-3-heptanone, 5-methyl-3-heptanone or diisobutyl ketone is preferable, and the second Isobutyl ketone is more preferable.

The first ketone-based solvent may have a linear structure, a branched structure, or a cyclic structure. The first ketone-based solvent may have, for example, a linear alkyl group or a branched alkyl group. Among them, from the viewpoint that the effect of the present invention is more excellent, it is preferable that the first ketone-based solvent has a branched alkyl group. On the other hand, from the viewpoint of volatility and/or solubility, the number of oxygen atoms in the molecule of the first ketone-based solvent is preferably one. In addition, the first ketone-based solvent is preferably composed only of an alkyl group and a carbonyl bond. In addition, it is preferable that the first ketone-based solvent does not have an aromatic ring group, an alkoxycarbonyl group, an oxo group, an amine group, and/or a carbamoyl group. When the first ketone-based solvent has a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, etc.), as the hetero atom, only an oxygen atom is preferred.

The first ketone solvent may be used singly, or two or more kinds may be used.

<Ester solvents with 8 to 10 carbon atoms other than acetate (hereinafter, also referred to as "first ester solvents")> The first ester-based solvent as the first organic solvent is an ester-based solvent having 8 to 10 carbon atoms other than acetate. Among them, from the viewpoint that the effect of the present invention is more excellent, the carbon number of the first ester-based solvent is preferably 9-10. In addition, in this specification, carbonate-based solvents are also included in the scope of ester-based solvents. In addition, acetate means an ester formed from acetic acid and alcohol, for example, butyl acetate etc. can be mentioned. The first ester-based solvent does not include acetate.

Regarding the first ester-based solvent, for example, dibutyl carbonate, heptyl formate, 2-ethylhexyl formate, isoamyl propionate, hexyl propionate, butyl butyrate, and isobutyl butyrate can be cited. , Butyl isobutyrate, isobutyl isobutyrate, ethyl caproate, propyl caproate, isopropyl caproate, butyl caproate, isobutyl caproate and 3,3-dimethylbutane Ethyl ester. Among them, from the viewpoint that the effect of the present invention is more excellent, as the first ester solvent, dibutyl carbonate, 2-ethylhexyl formate, isoamyl propionate, isobutyl butyrate, butyl isobutyrate , Isobutyl isobutyrate, ethyl caproate, butyl caproate, isopropyl caproate, isobutyl caproate or 3,3-dimethylbutane ethyl ester is preferred, 2-ethyl formate Hexyl ester, isoamyl propionate, isopropyl caproate, isobutyl caproate or ethyl 3,3-dimethylbutane are more preferred.

The first ester-based solvent has a linear structure, a branched structure, or a cyclic structure. The first ester-based solvent may have, for example, a linear alkyl group and a branched alkyl group. Among them, from the viewpoint that the effect of the present invention is more excellent, it is preferable that the first ester-based solvent has a branched alkyl group. On the other hand, from the viewpoint of volatility and/or solubility, the number of oxygen atoms in the molecule of the first ester-based solvent is preferably 2 to 3, and 2 is more preferable. In addition, the first ester-based solvent is preferably composed only of an alkyl group, an ester bond, and a hydrogen atom capable of bonding to the carbonyl carbon in the ester bond. In addition, it is preferable that the first ester-based solvent does not have an aromatic ring group, an oxo group, an amino group, and/or a carbamoyl group. When the first ester-based solvent has a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, etc.), only an oxygen atom is preferred as the hetero atom.

The first ester-based solvent may be used singly, or two or more kinds may be used.

<Aromatic hydrocarbon solvent with 8 to 10 carbon atoms (hereinafter, also referred to as "first aromatic hydrocarbon solvent")> The carbon number of the first aromatic hydrocarbon-based solvent as the first organic solvent is 8 to 10, and from the viewpoint that the effect of the present invention is more excellent, 9 to 10 are preferable. In addition, the aromatic hydrocarbon-based solvent refers to a hydrocarbon-based solvent having an aromatic ring structure. The aromatic hydrocarbon solvent only needs to have an aromatic ring structure, and may have an aliphatic hydrocarbon group.

Examples of the first aromatic hydrocarbon-based solvent include mesitylene, cumene, trimethylbenzene, 1,2,4,5-tetramethylbenzene, and p-cymene. Among them, from the viewpoint that the effect of the present invention is more excellent, as the first aromatic hydrocarbon solvent, mesitylene, cumene, or p-cymene is preferable, and mesitylene is more preferable.

From the viewpoint that the effect of the present invention is more excellent, it is preferable that the first aromatic hydrocarbon solvent has a linear alkyl group or a branched alkyl group. On the other hand, from the viewpoint of volatility and/or solubility, the first aromatic hydrocarbon solvent is preferably composed of only an aromatic ring and a linear or branched alkyl group.

The first aromatic hydrocarbon solvent may be used singly, or two or more kinds may be used.

From the viewpoint that the effect of the present invention is more excellent, the first organic solvent is preferably diisobutyl ketone, isopropyl caproate, or mesitylene. The 1st organic solvent may be used individually by 1 type, and may use 2 or more types. The content of the first organic solvent is preferably 1 to 90% by mass relative to the total mass of the treatment liquid, more preferably 3 to 75% by mass, and still more preferably 5 to 60% by mass.

〔Second Organic Solvent〕 The treatment liquid of the present invention contains a predetermined second organic solvent. The second organic solvent includes at least one solvent selected from the group consisting of a ketone solvent having 5 to 7 carbon atoms and an ester solvent having 5 to 7 carbon atoms other than acetate.

<A ketone solvent having 5 to 7 carbon atoms (hereinafter, also referred to as a "second ketone solvent")> The carbon number of the second ketone-based solvent as the second organic solvent is 5-7, and from the viewpoint that the effect of the present invention is more excellent, 5-6 is preferable.

As the second ketone solvent, for example, 3-methyl-2-butanone, 3,3-dimethyl-2-butanone, 2-methyl-3-pentanone, 3-methyl- 2-pentanone, 4-methyl-2-pentanone, diisopropyl ketone, 2-methyl-3-hexanone and 5-methyl-2-hexanone. Among them, from the viewpoint that the effect of the present invention is more excellent, as the second ketone solvent, 3-methyl-2-butanone, 2-methyl-3-pentanone, 3-methyl-2-pentanone, 4-methyl-2-pentanone, diisopropyl ketone, 2-methyl-3-hexanone or 5-methyl-2-hexanone is preferred, and diisopropyl ketone is more preferred.

The second ketone-based solvent may have a linear structure, a branched structure, or a cyclic structure. The second ketone solvent may have, for example, a linear alkyl group or a branched alkyl group. Among them, from the viewpoint that the effect of the present invention is more excellent, it is preferable that the second ketone solvent has a branched alkyl group. On the other hand, from the viewpoint of volatility and/or solubility, the number of oxygen atoms in the molecule of the second ketone solvent is preferably one. In addition, the second ketone solvent is preferably composed only of an alkyl group and a carbonyl bond. In addition, it is preferable that the second ketone solvent does not have an aromatic ring group, an alkoxycarbonyl group, an oxo group, an amine group, and/or a carbamoyl group. When the second ketone-based solvent has a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, etc.), the hetero atom is preferably only an oxygen atom.

The second ketone-based solvent may be used singly, or two or more kinds may be used.

<Ester solvents with 5 to 7 carbon atoms other than acetate (hereinafter also referred to as "second ester solvents")> The second ester-based solvent as the second organic solvent is an ester-based solvent having 5 to 7 carbon atoms other than acetate. Among them, from the viewpoint that the effect of the present invention is more excellent, the carbon number of the second ester-based solvent is preferably 5-6. In addition, the second ester-based solvent does not include acetate.

As the second ester solvent, for example, pentyl formate, isoamyl formate, tertiary amyl formate, hexyl formate, isopropyl propionate, isobutyl propionate, ethyl isobutyrate, carbonic acid Diethyl and dipropyl carbonate. Among them, from the viewpoint that the effect of the present invention is more excellent, as the second ester solvent, isoamyl formate, tertiary amyl formate, isopropyl propionate, isobutyl propionate, ethyl isobutyrate, or carbonic acid Diethyl is preferred, and isoamyl formate, isopropyl propionate or isobutyl propionate is more preferred.

The second ester-based solvent may have a linear structure, a branched structure, or a cyclic structure. The second ester-based solvent may have, for example, a linear alkyl group or a branched alkyl group. Among them, from the viewpoint that the effect of the present invention is more excellent, it is preferable that the second ester-based solvent has a branched alkyl group. On the other hand, from the viewpoint of volatility and/or solubility, the number of acid atoms in the molecule of the second ester-based solvent is preferably 2 to 3, and 2 is more preferable. In addition, the second ester-based solvent is preferably composed only of an alkyl group, an ester bond, and a hydrogen atom capable of bonding to the carbonyl carbon in the ester bond. In addition, it is preferable that the second ester-based solvent does not have an aromatic ring group, an oxo group, an amino group, and/or a carbamoyl group. When the second ester-based solvent has a hetero atom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, etc.), only an oxygen atom is preferred as the hetero atom.

The second ester-based solvent may be used singly, or two or more kinds may be used.

From the viewpoint of more excellent effects of the present invention, the second organic solvent is preferably diisopropyl ketone, isoamyl formate, or isopropyl propionate. The second organic solvent may be used singly, or two or more kinds may be used. The content of the second organic solvent is preferably 10 to 99% by mass relative to the total mass of the treatment liquid, more preferably 25 to 97% by mass, and still more preferably 40 to 95% by mass.

In addition, the treatment liquid may intentionally or inevitably contain the positional isomer of the above-mentioned organic solvent (for example, having a linear or branched alkyl group) together with the first organic solvent or the second organic solvent containing the treatment liquid. The positional isomers of the first organic solvent or the second organic solvent, etc.). The above-mentioned positional isomer may correspond to the first organic solvent or the second organic solvent, or may correspond to other components. When the treatment solution contains two or more compounds (at least one of the two or more compounds corresponding to the first or second organic solvent) that are related to each other's positional isomers, the other positional isomers are different. The total content of the compounds of the structure is more than 0% by mass and 1% by mass relative to 100% by mass of the compound with the largest content in these positional isomers (compounds corresponding to the first or second organic solvent are preferred) The following are better.

[The relationship between the first organic solvent and the second organic solvent] Preferably, the boiling points of the first organic solvent and the second organic solvent in the treatment liquid of the present invention are independently 80 to 250°C, more preferably 80 to 200°C, and even more preferably 90 to 220°C. In addition, the difference between the boiling points of the first organic solvent and the second organic solvent is not particularly limited. The boiling point of the first organic solvent minus the boiling point of the second organic solvent (bp1-bp2) is 0°C or higher. Preferably, it is more preferable to satisfy the relationship of formula (1) shown below, and it is more preferable to satisfy the relationship of formula (2). Formula (1): 5.0℃＜bp1-bp2＜100.0℃ Formula (2): 20.0℃＜bp1-bp2＜80.0℃ In the above, bp1 represents the boiling point (°C) of the first organic solvent, and bp2 represents the boiling point (°C) of the second organic solvent. The above boiling point is the boiling point at 1 atmosphere. When the treatment liquid contains two or more kinds of the first organic solvent and/or the second organic solvent, as long as there are at least one (preferably all) of the combination of the first organic solvent and the second organic solvent, satisfy the above The formula can be. Among them, it is preferable that the combination of the first organic solvent with the largest content and the second organic solvent with the largest content in the treatment liquid satisfies the above formula. The content mentioned here is the content based on quality.

Regarding the treatment liquid of the present invention, it is preferable that at least one of the first organic solvent and the second organic solvent has a branched alkyl group, and both the first organic solvent and the second organic solvent have a branched alkyl group. For better. In addition, the first organic solvent having a branched alkyl group means that at least one selected from the group consisting of a first ketone-based solvent, a first ester-based solvent, and a first aromatic hydrocarbon-based solvent has a branched alkyl group . In addition, the second organic solvent having a branched alkyl group means that at least one selected from the group consisting of the second ketone solvent and the second ester solvent has a branched alkyl group. When the treatment liquid contains two or more types of first organic solvents and/or second organic solvents, it is preferable that one or more types (preferably all types) of the first organic solvents that can be present have a branched alkyl group. It is more preferable that one or more kinds (preferably all kinds) of the second organic solvent that can exist in plural have a branched alkyl group. Among them, it is preferable that the first organic solvent with the largest content has a branched alkyl group. In addition, it is preferable that the group of the second organic solvent having the largest content has a branched alkyl group. The content mentioned here is the content based on quality.

The treatment liquid of the present invention only needs to contain at least one of the above-mentioned first organic solvent and the above-mentioned second organic solvent. The treatment liquid of the present invention can be appropriately prepared according to the purpose. When a processing liquid is used as a developer, since a certain degree of solubility is required, it is preferable that the content of the second organic solvent is large. On the other hand, when the treatment liquid is used as a cleaning liquid after development (hereinafter, also referred to as a "rinsing liquid"), it is preferable that the content of the first organic solvent is large in order to suppress the thinning of the pattern. For example, the mass ratio of the content of the second organic solvent to the content of the first organic solvent (the content of the second organic solvent/the content of the first organic solvent) is preferably 10/90 to 99/1, 25/ 75-97/3 is more preferable, and 40/60-95/5 is still more preferable. In the treatment liquid of the present invention, the total content of the first organic solvent and the second organic solvent relative to the total mass of the treatment liquid is preferably 95.0% by mass or more, more preferably 98.0% by mass or more, and 99.0% by mass or more More preferably, 99.5% by mass or more is particularly preferable, and 99.9% by mass or more is most preferable. Moreover, as the upper limit of the said total content, it is 100 mass %, for example.

〔Other ingredients〕 The treatment liquid of the present invention may contain components other than those described above.

＜Metal composition＞ The treatment liquid may contain metal components. Examples of the metal component include metal particles and metal ions. For example, the content of the metal component indicates the total content of metal particles and metal ions. The treatment liquid may contain any one of metal particles and metal ions, or may contain two types.

As the metal atom contained in the metal component, for example, a group selected from Ag, Al, As, Au, Ba, Ca, Cd, Co, Cr, Cu, Fe, Ga, Ge, K, Li, Mg, Metal atoms in the group of Mn, Mo, Na, Ni, Pb, Sn, Sr, Ti and Zn. The metal component may include one type of metal atom, or may include two or more types. The metal particles may be a monomer, an alloy, or exist in the form of an association of metal and organic matter. The metal component may be a metal component that is inevitably contained in each component (raw material) contained in the treatment liquid, or it may be a metal component that is inevitably contained during the manufacture, storage, and/or transfer of the treatment liquid, or Add intentionally.

When the treatment liquid contains a metal component, the content of the metal component relative to the total mass of the treatment liquid is preferably more than 0 mass ppt and 1 mass ppm or less, more preferably more than 0 mass ppt and 10 mass ppb or less, and more than 0 mass ppt and 10 mass ppt or less is more preferable. In addition, the type and content of the metal component in the treatment liquid can be measured by the ICP-MS method (inductively coupled plasma mass spectrometry).

<Ionic liquid> The treatment liquid of the present invention may also contain the following ionic liquid. In addition, when the treatment liquid contains an ionic liquid, the ionic liquid is regarded as being not contained in the first organic solvent and the second organic solvent. As the ionic liquid, for example, it has an aromatic ion such as a pyridinium ion or an imidazolium ion, or an aliphatic amine ion such as a trimethylhexylammonium ion as a cation. As an anion, with ^{_{NO 3 -, CH 3 CO 2}} -, BF 6 - or PF ₆ ^- inorganic ionic, or _{(CF 3 SO 2) 2 N} -, CF 3 CO 2 -, or CF ₃ SO ₂ ^-, etc. Ionic liquids such as fluorine-containing organic anions; quaternary ammonium salt-based ionic liquids are preferred.

As commercial products of ionic liquids, for example, IL-P14 and IL-A2 (manufactured by KOEI CHEMICAL INDUSTRY CO., LTD.); Elegan SS-100 (manufactured by NOF CORPORATION) and other quaternary ammonium salt-based ionic Liquid etc. An ionic liquid may be used individually by 1 type, and may use 2 or more types together.

When the treatment liquid of the present invention contains an ionic liquid, the content of the ionic liquid relative to the total mass of the treatment liquid is preferably 0.5 to 15% by mass, more preferably 1 to 10% by mass, and more preferably 1 to 5% by mass. good.

＜Surface active agent＞ The treatment liquid of the present invention may also contain a surfactant. When the treatment liquid contains a surfactant, the wettability of the treatment liquid to the resist film is improved, and development and/or washing can be performed more effectively. As the surfactant, the same surfactants as those that can be contained in the resist composition described later can be used. Surfactant may be used individually by 1 type, and may use 2 or more types together. When the treatment liquid of the present invention contains a surfactant, the content of the surfactant relative to the total mass of the treatment liquid is preferably 0.001 to 5% by mass, more preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass. good.

＜Antioxidant＞ The treatment liquid of the present invention may also contain an antioxidant. As the antioxidant, an amine-based antioxidant or a phenol-based antioxidant is preferable. Antioxidant may be used individually by 1 type, and may use 2 or more types together. When the treatment liquid of the present invention contains an antioxidant, the content of the antioxidant relative to the total mass of the treatment liquid is preferably 0.0001 to 1% by mass, more preferably 0.0001 to 0.1% by mass, and still more preferably 0.0001 to 0.01% by mass.

＜Basic compound＞ The treatment liquid of the present invention may also contain a basic compound. As a specific example of a basic compound, the compound exemplified as an acid diffusion control agent which can be contained in the resist composition mentioned later can be mentioned. A basic compound may be used individually by 1 type, and may use 2 or more types together. When the treatment liquid of the present invention contains a basic compound, the content of the basic compound relative to the total mass of the treatment liquid is preferably 10% by mass or less, and more preferably 0.5 to 5% by mass. In addition, in the present invention, only one type of the above-mentioned basic compound may be used, or two or more types with different chemical structures may be used in combination.

＜Other solvents＞ The treatment liquid of the present invention may also contain other solvents. When the processing liquid of the present invention is used as a developer, the processing liquid of the present invention may contain other organic solvents other than the above-mentioned first organic solvent and the above-mentioned second organic solvent. When the treatment liquid of the present invention is used as a rinsing liquid, the treatment liquid of the present invention may also contain other organic solvents other than the first organic solvent and the second organic solvent. The other organic solvents are not particularly limited. For example, organic solvents such as hydrocarbon-based solvents, ketone-based solvents, ester-based solvents, alcohol-based solvents, amide-based solvents, and/or ether-based solvents can be cited, and they do not correspond to the above An organic solvent of any one of the first organic solvent and the above-mentioned second organic solvent.

＜Organic substances with a boiling point of 300°C or higher＞ When a treatment solution containing an organic substance with a boiling point of 300° C. or higher is applied to a semiconductor device manufacturing process, the above-mentioned organic substance with a high boiling point does not volatilize and remains in it, which may cause defects in the substrate. As an organic substance with a boiling point of 300°C or higher, for example, it is considered that the resin component or plasticizer contained in the plastic material (for example, O-ring, etc.) used to manufacture the components of the device is presumed to be in a certain part of the manufacturing process. Dissolve in the liquid at all times. When the treatment liquid contains an organic substance with a boiling point of 300°C or higher, when used in the semiconductor device manufacturing process, from the viewpoint of suppressing defects of the substrate, the content of the organic substance with a boiling point of 300°C or higher is relative to the total amount of the treatment liquid. The mass is preferably 0.001 to 50 mass ppm, more preferably 0.001 to 30 mass ppm, more preferably 0.001 to 15 mass ppm, particularly preferably 0.001 to 10 mass ppm, and most preferably 0.001 to 1 mass ppm.

For example, when the above-mentioned treatment liquid is used as a developer and contacts the substrate, the organic matter is prevented from being volatilized and left on the substrate surface to become a defect. The content of the above-mentioned organic matter with a boiling point of 300°C or higher is 30 relative to the total mass of the treatment liquid. Mass ppm or less is preferable. For example, when the above-mentioned treatment liquid is used as a developer and contacts the substrate, the above-mentioned boiling point is It is more preferable that the content of the organic matter at 300°C or higher is 15 mass ppm or less with respect to the total mass of the treatment liquid. As organic matter above 300°C that can be contained in the treatment liquid, components such as dioctyl phthalate (DOP, boiling point 385°C) eluted from O-rings, and diisononyl phthalate (DINP, boiling point) 403°C), dioctyl adipate (DOA, boiling point 335°C), dibutyl phthalate (DBP, boiling point 340°C) and EPDM (EPDM, boiling point 300-450°C), etc.

As a method of setting the content of the organic substance having a boiling point of 300° C. or higher in the treatment liquid within the above-mentioned range, the method mentioned in the purification process described later can be mentioned.

[Pattern forming method] The present invention also relates to a pattern forming method using the above-mentioned treatment liquid. The pattern forming method includes, for example: (I) The resist film formation process of using resist composition to form resist film; (Ii) Exposure process for exposing the above-mentioned resist film; and (Iii) A treatment process for treating the exposed resist film with the treatment liquid.

Hereinafter, each process included in the pattern forming method will be described. In addition, as an example of the processing process, the development process and the washing process will be described separately.

＜(i) Process for forming resist film＞ The resist film forming process is a process in which a resist composition is used to form a resist film. When a resist composition is used to form a resist film, for example, each component described below is dissolved in a solvent to prepare a resist composition, and after filtering with a filter as needed, the resist composition is coated on the support (substrate). Agent composition to form a resist film. The pore size of the filter is preferably 0.1 μm or less, more preferably 0.05 μm or less, and even more preferably 0.03 μm or less. As the material of the filter, polytetrafluoroethylene, polyethylene or nylon is preferable.

The resist composition is coated on the support (substrate) by an appropriate coating method such as a spin coater. Then, the coating film (the coating film of the coated resist composition) is dried to form a resist film. Various undercoating films (inorganic film, organic film and anti-reflection film) can also be formed on the lower layer of the resist film as needed.

The support for forming the resist film is not particularly limited. In addition to the manufacturing process of ICs and other semiconductors or the manufacturing process of circuit boards such as liquid crystals or thermal heads, it can also be used in other photolithography processes such as photolithography processes. Substrate. Specific examples of the support include inorganic substrates such as _{silicon, SiO 2 and SiN.} The above-mentioned substrates also include semiconductor substrates composed of a single layer and semiconductor substrates composed of multiple layers. The material constituting the semiconductor substrate composed of a single layer is not particularly limited, and it is usually preferably composed of a group III-V compound such as silicon, silicon germanium, GaAs, or any combination thereof. When a semiconductor substrate is composed of multiple layers, the structure is not particularly limited. For example, an integrated circuit structure in which interconnect features such as metal wires and dielectric materials are exposed can be provided on the above-mentioned semiconductor substrate such as silicon. . As metals and alloys used in the interconnect structure, for example, aluminum and copper, alloy aluminum, copper, titanium, tantalum, cobalt, silicon, titanium nitride, tantalum nitride, and tungsten can be cited, but they are not limited to Such. In addition, the semiconductor substrate may also have layers of interlayer dielectric layer, silicon oxide, silicon nitride, silicon carbide, and carbon-doped silicon oxide.

As a drying method, heating and drying are generally used. As the heating temperature, 80 to 180°C is preferred, 80 to 150°C is more preferred, 80 to 140°C is more preferred, and 80 to 130°C is particularly preferred. The heating time is preferably 30 to 1000 seconds, more preferably 60 to 800 seconds, and more preferably 60 to 600 seconds.

The thickness of the resist film is generally 200 nm or less, preferably 100 nm or less. For example, in order to analyze 1:1 line and space patterns with a size of 30 nm or less, the thickness of the resist film is preferably 50 nm or less. As long as the film thickness is 50 nm or less, it is less likely to cause pattern collapse when the development process described later is applied, and better resolution performance can be obtained. From the viewpoint of more excellent etching resistance and resolution, the film thickness is preferably 15 to 70 nm, and more preferably 15 to 65 nm.

In addition, a resist underlayer film (for example, SOG (Spin On Glass), SOC (Spin On Carbon), and anti-reflection film) may be formed between the resist film and the support as required. As the material constituting the resist underlayer film, a known organic or inorganic material can be suitably used. It is also possible to form a protective film (top coat layer) on the upper layer of the resist film. As the protective film, a known material can be suitably used. For example, the specification of U.S. Patent Application Publication No. 2007/0178407, the specification of U.S. Patent Application Publication No. 2008/0085466, the specification of U.S. Patent Application Publication No. 2007/0275326, and the specification of U.S. Patent Application Publication No. 2016/0299432 can be preferably used. The composition for forming a protective film disclosed in the specification of U.S. Patent Application Publication No. 2013/0244438 and International Patent Application Publication No. 2016/157988A. As the composition for forming a protective film, those containing the above-mentioned acid diffusion control agent are preferred. Also, for example, the upper layer film can be formed based on the description in [0072] to [0082] of JP 2014-059543 A. The thickness of the protective film is preferably 10 to 200 nm, more preferably 20 to 100 nm, and even more preferably 40 to 80 nm.

＜(ii) Exposure process＞ In the pattern formation method, (ii) the exposure method in the exposure process can also be liquid immersion exposure. The pattern formation method includes (iv) preheating (PB: PreBake, hereinafter, also referred to as “post-coating baking”) before the (ii) exposure process.) The process is preferred. The pattern formation method preferably includes (v) a post-exposure heating (PEB: Post Exposure Bake, also known as post-exposure bake) process after (ii) the exposure process and before (iii) the development process. The pattern forming method may also include a plurality of (ii) exposure processes. The pattern forming method may also include a plurality of (iv) pre-heating processes. The pattern formation method may also include a plurality of (v) post-exposure heating processes.

In the pattern forming method, (ii) the exposure process can be performed by a well-known method.

The heating temperature is preferably 80-150°C in both (iv) the pre-heating process and (v) the post-exposure heating process, more preferably 80-140°C, and even more preferably 80-130°C. The heating time is preferably 30-1000 seconds in both (iv) the pre-heating process and (v) the post-exposure heating process, more preferably 60-800 seconds, and still more preferably 60-600 seconds. Heating can be performed using mechanisms installed in the exposure device and the developing device, or can be performed using a heating plate or the like.

The wavelength of the light source used in the exposure process is not limited. For example, infrared light, visible light, ultraviolet light, extreme ultraviolet light, extreme ultraviolet light (EUV light), X-rays, and electron beams can be cited. Among them, far ultraviolet rays are preferred, and the wavelength is preferably 250 nm or less, more preferably 220 nm or less, and more preferably 1 to 200 nm. Specifically, KrF excimer laser (248nm), ArF excimer laser (193nm), F ₂ excimer laser (157nm), X-ray, EUV (13nm) and electron beam, etc., KrF excimer laser , ArF excimer laser, EUV or electron beam is preferable, EUV or electron beam is more preferable.

＜(iii) Process of processing the exposed film＞ (Iii) The process of processing the exposed film, which usually includes: (vi) a development process, which is developed by a developer (development process); and (vii) a washing process, which is cleaned by a rinse (rinsing process) ). The treatment liquid of the present invention can be used as a developer in the development process, and can also be used as a rinsing liquid in the rinsing process. Among them, it is preferable to use it as a rinsing liquid in the rinsing process. When the processing liquid of the present invention is used as a rinsing liquid in a rinsing process, it is preferable to use a processing liquid other than the processing liquid of the present invention as the developer in the development process.

(Development process) The development process is a process in which the exposed resist film is developed by a developer.

As the development method, for example, a method of immersing the substrate in a tank filled with developer for a period of time (dipping method), and a method of causing the developer to rise to the surface of the substrate by surface tension and stand still for a period of time (coating liquid ( Puddle method), the method of spraying developer on the surface of the substrate (spraying method), and the method of continuously spraying the developer while scanning the nozzle of the developer on a substrate rotating at a certain speed (dynamic distribution method), etc. In addition, after the development process, a process of stopping the development while replacing with other solvents can also be implemented. The development time is preferably 10 to 300 seconds, and more preferably 20 to 120 seconds. As the temperature of the developer, 0 to 50°C is preferable, and 15 to 35°C is more preferable.

As the developer, the above-mentioned treatment liquid may be used, or other developer may be used. In addition to the development using the treatment liquid, an alkali developer can also be used for development (so-called double development).

"Other Developers" Hereinafter, other developing solutions (developing solutions other than the processing solution of the present invention) will be described. The vapor pressure of the organic solvent used in the developer (the overall vapor pressure when the solvent is mixed) is preferably 5kPa or less at 20°C, more preferably 3kPa or less, and even more preferably 2kPa or less. By setting the vapor pressure of the organic solvent to 5 kPa or less, the evaporation of the developer on the substrate or in the developing cup is suppressed, the temperature uniformity in the substrate surface is improved, and as a result, the dimensional uniformity in the substrate surface becomes good. The organic solvent used in the developer is not particularly limited, and examples include solvents such as ester solvents, ketone solvents, alcohol solvents, amide solvents, ether solvents, and hydrocarbon solvents.

As the developer, it is preferable to include one or more solvents selected from the group consisting of ketone solvents, ester solvents, alcohol solvents, and ether solvents.

As ester solvents, for example, methyl acetate, ethyl acetate, butyl acetate, isobutyl acetate, amyl acetate, propyl acetate, isopropyl acetate, amyl acetate (Amyl acetate) (amyl acetate) Pentyl acetate), isoamyl acetate (isopentyl acetate), 3-methylbutyl acetate, 2-methylbutyl acetate, 1-methylbutyl acetate, Hexyl acetate, isohexyl acetate, heptyl acetate, octyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, propylene glycol monomethyl ether acetate (PGMEA; alias 1-methoxy-2-ethyl Oxypropane), ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol mono Methyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, two Ethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methyl Oxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate Ethyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl ethyl Ester, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, lactic acid Propyl ester, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetylacetate, ethyl acetylacetate, methyl propionate Ester, ethyl propionate, propyl propionate, isopropyl propionate, butyl propionate, pentyl propionate, hexyl propionate, heptyl propionate, butyl butyrate, isobutyl butyrate, butyl Amyl pentate, hexyl butyrate, isobutyl isobutyrate, propyl valerate, isopropyl valerate, butyl valerate, pentyl valerate, ethyl caproate, propyl caproate, butyl caproate Ester, isobutyl caproate, methyl heptanoate, ethyl heptanoate, propyl heptanoate, cyclohexyl acetate, cycloheptyl acetate, 2-ethylhexyl acetate, cyclopentyl propionate, 2-hydroxy Methyl propionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate and propyl Group -3-methoxy propionate and so on. Among them, butyl acetate, pentyl acetate, isoamyl acetate, 2-methylbutyl acetate, 1-methylbutyl acetate, hexyl acetate, pentyl propionate, hexyl propionate, heptyl propionate or Butyl butyrate is preferred, and isoamyl acetate is more preferred.

As the ketone solvent, for example, 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone, 4-heptanone, 1-hexanone, 2-hexanone, Ketones, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetone, acetonyl acetone, ionone, diacetone alcohol, ethyl Methanol, acetophenone, methyl naphthyl ketone, isophorone, propylene carbonate and gamma-butyrolactone, etc. Among them, 2-heptanone is preferred.

As the alcohol solvent, for example, methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol, 3-methyl-1-butanol, tert-butanol, 1-pentanol, Alcohol, 2-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-decanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol Alcohol, 3-octanol, 4-octanol, 3-methyl-3-pentanol, cyclopentanol, 2,3-dimethyl-2-butanol, 3,3-dimethyl-2-butanol Alcohol, 2-methyl-2-pentanol, 2-methyl-3-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-2-pentanol Alcohol, 4-methyl-3-pentanol, cyclohexanol, 5-methyl-2-hexanol, 4-methyl-2-hexanol, 4,5-dimethyl-2-hexanol, 6 -Methyl-2-heptanol, 7-methyl-2-octanol, 8-methyl-2-nonanol, 9-methyl-2-decanol and 3-methoxy-1-butanol, etc. Alcohol (monovalent alcohol); glycol solvents such as ethylene glycol, diethylene glycol and triethylene glycol; ethylene glycol monomethyl ether, propylene glycol monomethyl ether (PGME; alias 1-methoxy-2- Propanol), diethylene glycol monomethyl ether, triethylene glycol monoethyl ether, methoxymethyl butanol, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monoethyl ether , Propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol monophenyl ether and other glycol ether solvents containing hydroxyl groups. Among them, glycol ether solvents are preferred.

As ether solvents, for example, in addition to glycol ether solvents containing the above-mentioned hydroxyl groups, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and other non-hydroxyl-free solvents can also be mentioned. Glycol ether-based solvents, aromatic ether solvents such as anisole and phenyl ethyl ether, dikoyama, tetrahydrofuran, tetrahydropyran, perfluoro-2-butyltetrahydrofuran, perfluorotetrahydrofuran, 1,4-㗁kouyama And isopropyl ether, etc. Among them, glycol ether solvents or aromatic ether solvents such as anisole are preferred.

As the amide-based solvents, for example, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, and hexamethyltrimethylphosphate Amine, 1,3-dimethyl-2-imidazolidinone, etc.

Examples of hydrocarbon solvents include pentane, hexane, octane, nonane, decane, dodecane, undecane, hexadecane, 2,2,4-trimethylpentane, 2 , 2,3-Trimethylhexane, perfluorohexane and perfluoroheptane and other aliphatic hydrocarbon solvents; toluene, xylene, ethylbenzene, propylbenzene, 1-methylpropylbenzene, 2- Aromatic hydrocarbon solvents such as methylpropylbenzene, dimethylbenzene, diethylbenzene, ethylmethylbenzene, trimethylbenzene, ethyldimethylbenzene, and dipropylbenzene. In addition, as the hydrocarbon solvent, unsaturated hydrocarbon solvents can also be used. For example, unsaturated hydrocarbon solvents such as octene, nonene, decene, undecene, dodecene, and hexadecene can be mentioned. . The number of double bonds or triple bonds possessed by the unsaturated hydrocarbon solvent is not particularly limited, and it may be located at any position in the hydrocarbon chain. In addition, when the unsaturated hydrocarbon solvent has a double bond, the cis isomer and the trans isomer may be mixed. In addition, the aliphatic hydrocarbon-based solvent as the hydrocarbon-based solvent may be a mixture of compounds having the same carbon number and different structures. For example, when decane is used as an aliphatic hydrocarbon solvent, 2-methylnonane, 2,2-dimethyloctane, 4-ethyloctane, and isooctane are compounds with the same carbon number and different structures The aliphatic hydrocarbon solvent may also be included. In addition, the above-mentioned compounds having the same carbon number and different structures may include only one type, or may include a plurality of types as described above.

From the viewpoint that when EUV light and electron beam are used in the above exposure process, the swelling of the resist film can be further suppressed, as the developer, the carbon number is 6 or more (6-14 is preferable, and 6-12 is more preferable. 6 to 10 are more preferable), and ester-based solvents having 2 or less heteroatoms are preferable. As said hetero atom, what is necessary is just an atom other than a carbon atom and a hydrogen atom, For example, an oxygen atom, a nitrogen atom, a sulfur atom, etc. are mentioned. The number of heteroatoms is preferably 2 or less. Specific examples of ester solvents having 6 or more carbon atoms and 2 or less heteroatoms are selected from the group consisting of butyl acetate, pentyl acetate, isoamyl acetate, 2-methylbutyl acetate, and 1-methylbutyl acetate. Ester, hexyl acetate, pentyl propionate, hexyl propionate, heptyl propionate, butyl butyrate, butyl isobutyrate and isobutyl isobutyrate are preferred, and isopentyl acetate Ester or butyl isobutyrate is more preferable.

From the viewpoint of further suppressing the swelling of the resist film when EUV light and electron beams are used in the above exposure process, it can also be used as a developer instead of the above-mentioned ester solvents with 6 or more carbon atoms and 2 or less heteroatoms. A mixed solvent of an ester solvent and a hydrocarbon solvent or a mixed solvent of a ketone solvent and a hydrocarbon solvent.

In the above-mentioned mixed solvent, the content of the hydrocarbon-based solvent depends on the solvent solubility of the resist film, and therefore is not particularly limited, as long as it is appropriately prepared to determine the required amount.

Among the mixed solvents of the ester solvent and the hydrocarbon solvent, isoamyl acetate is preferred as the ester solvent. From the viewpoint of easy adjustment of the solubility of the resist film, as the hydrocarbon solvent, a saturated hydrocarbon solvent (for example, octane, nonane, decane, dodecane, undecane, hexadecane, etc.) is preferred .

Among the mixed solvents of the ketone solvent and the hydrocarbon solvent, examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, and 2-heptanone (a Pentyl ketone), 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, 2,5-dimethyl-4-hexanone, cyclohexanone, methylcyclohexanone, Propiophenone, methyl ethyl ketone, methyl isobutyl ketone, acetone, acetonyl acetone, ionone, diacetone alcohol, acetol, acetophenone, methyl naphthyl ketone, isophorone and Propylene carbonate, etc., preferably diisobutyl ketone or 2,5-dimethyl-4-hexanone. From the viewpoint of easy adjustment of the solubility of the resist film, as the hydrocarbon solvent, a saturated hydrocarbon solvent (for example, octane, nonane, decane, dodecane, undecane, hexadecane, etc.) is preferred .

The above-mentioned solvents may be mixed with plural kinds, and may be mixed with solvents or water other than the above. The moisture content of the entire developer is preferably less than 50% by mass, more preferably less than 20% by mass, even more preferably less than 10% by mass, and it is particularly preferable that it contains substantially no water. The content of the organic solvent relative to the organic developer is preferably 50-100% by mass relative to the total mass of the developer, more preferably 80-100% by mass, more preferably 90-100% by mass, 95-100 The quality% is particularly good.

The developer may also contain an appropriate amount of well-known surfactants as needed.

The content of the surfactant relative to the total amount of the developer is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and more preferably 0.01 to 0.5% by mass.

The developer may also contain alkaline compounds. As a specific example of a basic compound, the compound exemplified as an acid diffusion control agent which can be contained in the resist composition mentioned later can be mentioned.

As the organic solvent used as the developer, in addition to the above-mentioned ester-based solvent, a solvent represented by the following general formula (S1) or the following general formula (S2) is also preferable. As the above-mentioned ester-based solvent, the solvent represented by the general formula (S1) is more preferable, and the alkyl acetate is more preferably, butyl acetate, amyl acetate (pentyl acetate) or acetic acid Isoamyl acetate (isopentyl acetate) is particularly preferred.

R-C(=O)-O-R’ general formula (S1)

In the general formula (S1), R and R'each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group, or a halogen atom. R and R'may be bonded to each other to form a ring. The number of carbon atoms in the alkyl group, alkoxy group, and alkoxycarbonyl group represented by R and R'is preferably 1-15, and the number of carbon atoms in the cycloalkyl group is preferably 3-15. The alkyl group, cycloalkyl group, alkoxy group and alkoxycarbonyl group represented by R and R', and the ring formed by bonding R and R'to each other may have a substituent. The substituent is not particularly limited, and examples thereof include a hydroxyl group, a carbonyl group-containing group (for example, an acyl group, an aldehyde group, and an alkoxycarbonyl group, etc.), a cyano group, and the like. As R and R', among them, a hydrogen atom or an alkyl group is preferred.

As the solvent represented by the general formula (S1), for example, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, Methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, Propyl Pyruvate, Butyl Pyruvate, Methyl Acetate, Ethyl Acetate, Methyl Propionate, Ethyl Propionate, Propyl Propionate, Isopropyl Propionate, Methyl 2-Hydroxypropionate And ethyl 2-hydroxypropionate and so on.

Among them, as R and R', an unsubstituted alkyl group is preferred. As the solvent represented by the general formula (S1), alkyl acetate is preferred, butyl acetate, amyl acetate (pentyl acetate) or isoamyl acetate (acetic acid) Isopentyl acetate is more preferable, and isoamyl acetate is still more preferable.

When the developer contains the solvent represented by the general formula (S1), the developer may further contain one or more other organic solvents (hereinafter also referred to as “combined solvent”). The combined solvent is not particularly limited as long as it can be mixed in the solvent represented by the general formula (S1) without being separated. Examples include ester solvents, ketones and other solvents other than the solvent represented by the general formula (S1). Solvents in the group of solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents. The solvent used in combination may be one type or two types. From the viewpoint of obtaining stable performance, one type is preferable. When the developer is a mixed solvent of the solvent represented by the general formula (S1) and a combined solvent, the content of the solvent represented by the general formula (S1) and the mass ratio of the solvent represented by the general formula (S1) are The content mass/the content mass of the combined solvent] is usually 20/80～99/1, 50/50～97/3 is better, 60/40～95/5 is more preferably, 60/40～90/10 is more Better.

As the organic solvent used as the developer, a solvent represented by the following general formula (S2) is also preferable.

R’’-C(=O)-O-R’’’-O-R’’’’ General formula (S2)

In the general formula (S2), R’’ and R’’’’ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, a hydroxyl group, a cyano group or a halogen atom. R'' and R'''' may be bonded to each other to form a ring. As R'' and R'''', a hydrogen atom or an alkyl group is preferable. As the carbon number of the alkyl group, alkoxy group, and alkoxycarbonyl group represented by R'’ and R’’’’, 1 to 15 are preferred, and as the carbon number of the cycloalkyl group, 3 to 15 are preferred. R’’’ represents an alkylene group or a cycloalkylene group, and an alkylene group is preferred. The number of carbon atoms in the alkylene group represented by R''' is preferably from 1 to 10, and the number of carbon atoms in the cycloalkylene group represented by R''' is preferably from 3 to 10. In addition, the alkylene group represented by R''' may have an ether bond in the alkylene chain. Alkyl, cycloalkyl, alkoxy and alkoxycarbonyl represented by R'' and R'''', alkylene and cycloalkylene represented by R''', and R'' and R ""The ring formed by bonding to each other may have a substituent. The substituent is not particularly limited, and examples thereof include a hydroxyl group, a carbonyl group-containing group (for example, an acyl group, an aldehyde group, and an alkoxycarbonyl group, etc.), a cyano group, and the like.

As the solvent represented by the general formula (S2), for example, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether ethyl Ester, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol Monobutyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methyl-3-methoxypropionate, ethyl-3-methyl Oxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, ethyl methoxyacetate, ethyl ethoxyacetate, 2-methoxybutane Acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3- Methoxybutyl acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl ethyl Ester, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxy Pentyl acetate, 3-methyl-4-methoxypentyl acetate and 4-methyl-4-methoxypentyl acetate, etc. Among them, propylene glycol monomethyl ether acetate is preferred. Among these, R'' and R'''' are unsubstituted alkyl groups, R''' is preferably an unsubstituted alkylene group, and R'' and R'''' are methyl groups and It is more preferable that any one of ethyl groups is, and it is more preferable that R" and R"" are methyl groups.

When the developer contains the solvent represented by the general formula (S2), the developer may further contain one or more solvents in combination. There are no particular restrictions on the combined solvent as long as it can be mixed in the solvent represented by the general formula (S2) without separation. Examples include ester solvents, ketones and other solvents other than the solvent represented by the general formula (S2). Solvents in the group of solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents. The solvent used in combination may be one type or two types. From the viewpoint of obtaining stable performance, one type is preferable. When the developer is a mixed solvent of the solvent represented by the general formula (S2) and a combined solvent, the content of the solvent represented by the general formula (S2) and the mass ratio of the solvent represented by the general formula (S2) are The content mass/the content mass of the combined solvent] is usually 20/80～99/1, 50/50～97/3 is better, 60/40～95/5 is more preferably, 60/40～90/10 is more Better.

In addition, as the organic solvent used as the developer, an ether solvent containing one or more aromatic rings is also preferable, the solvent represented by the following general formula (S3) is more preferable, and anisole is still more preferable.

[Chemical formula 1]

In the general formula (S3), R _S represents an alkyl group. As the alkyl group, the number of carbon atoms is preferably 1 to 4, the methyl group or the ethyl group is more preferable, and the methyl group is more preferable.

As the developer (other developer), an aqueous alkali developer can be used.

(Flushing process) The rinsing process is a process of washing (rinsing) with a rinsing liquid after the above-mentioned development process.

In the rinsing process, the above-mentioned rinsing solution is used to clean the developed substrate. The method of cleaning treatment is not particularly limited. For example, it can be applied to a method of continuously spraying a rinse liquid on a substrate rotating at a certain speed (rotary spray method), and a method of immersing the substrate for a period of time in a tank filled with rinse liquid (dipping Method), a method of spraying a rinsing liquid on the surface of the substrate (spraying method), etc., in which the rotary jet method is used for cleaning, and after cleaning, the substrate is rotated at a rotation speed of 2000 to 4000 rpm to remove the rinsing liquid from the substrate. good. The rinse time is preferably 10 to 300 seconds, more preferably 10 to 180 seconds, and even more preferably 20 to 120 seconds. As the temperature of the rinse liquid, 0-50°C is preferred, and 15-35°C is more preferred.

As the rinsing liquid, the above-mentioned treatment liquid can be used, and other rinsing liquids can also be used. As other rinsing liquids, for example, the above-mentioned other developing liquids and water can be cited.

Furthermore, after the development process or the rinsing process, a process of removing the developer or rinsing liquid adhering to the pattern with a supercritical fluid can be performed. Furthermore, after the development process, the rinsing process, or the supercritical fluid-based process, a drying process may be performed in order to remove the solvent remaining in the pattern. The drying temperature is preferably 40 to 160°C, more preferably 50 to 150°C, and even more preferably 50 to 110°C. The drying time is preferably 15 to 300 seconds, and more preferably 15 to 180 seconds.

In the pattern forming method of the present invention, the processing liquid of the present invention is used as at least one of a developer and a rinse liquid. Among them, the treatment liquid of the present invention is preferably used as a rinse liquid.

For example, when an ester-based solvent is used as the developer in the development process and the processing solution of the present invention is used as the rinse in the rinse process to perform pattern formation, the interval between the supply of the developer and the rinse to the exposed resist film is set to More than 1 second is preferable. Setting the supply interval of the developer and the rinsing liquid to a predetermined time or longer can suppress the deterioration of the solubility of the unexposed area of the resist film after exposure, and can suppress the increase in defects due to the solvent casting method.

In addition, the developer and the rinse liquid are usually stored in a general-purpose waste liquid tank through a pipe after use. At this time, if an ester-based solvent is used as a developer in the development process and the treatment solution of the present invention is used as a rinse in the rinsing process, the resist dissolved in the developer will be precipitated, resulting in adhesion to the back of the substrate and The side of the piping, etc., may further contaminate the device. In order to solve the above problems, there is a method of passing the solvent for dissolving the resist through the piping again. As a method of passing through the piping, there are a method of washing the back or side surface of the substrate with a solvent that dissolves the resist after washing with a rinse solution, and a method in which the solvent that dissolves the resist does not contact the resist and flows out through the piping.的方法。 The method. The solvent passing through the piping is not particularly limited as long as it can dissolve the anti-reagent. For example, an organic solvent used as the above-mentioned developer can be mentioned. Specifically, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol monomethyl ether propionate, propylene glycol Monoethyl ether propionate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol Monomethyl ether, ethylene glycol monoethyl ether, 2-heptanone, ethyl lactate, 1-propanol and acetone, etc. Among them, PGMEA, PGME or cyclohexanone are preferred.

In addition, as another method to solve the above-mentioned problems, in order to prevent the precipitation of the resist in the waste liquid flowing into the waste liquid tank through the pipe after use, the ratio of the amount of the developer and the rinse liquid flowing into the pipe after use can be mentioned. The method of adjusting the ratio of the amount of the resist without precipitation, and the method of further mixing the solvent with high solubility to the resist in the developer and rinsing liquid flowing into the pipe after use. As a specific method, for example, between the development process and the rinsing process, the continuous supply of SP value to the back of the wafer is higher than the first organic solvent and/or the second organic solvent contained in the processing solution of the present invention. This is a method of suppressing the precipitation/precipitation of the resist in the waste liquid flowing through the piping to the waste liquid tank after use.

Moreover, it is also preferable that the developer and the rinse liquid are separately contained in different waste liquid tanks after use. For example, when an ester solvent is used as the developer in the development process and the processing liquid of the present invention is used as the rinsing liquid in the rinsing process to perform pattern formation, if it is stored in the same waste liquid tank through piping after use, It causes the components contained in the resist composition such as resin dissolved in the developer to be analyzed (precipitation/solidification), which may cause device contamination. Specifically, due to the precipitated components, not only the clogging of the waste liquid piping, but also the contamination of the processing chamber occurs. In order to solve the above-mentioned problems, it is preferable that the developer and the rinsing liquid are separately contained in different waste liquid tanks by pipe replacement or by replacement of the processing chamber after use. In addition, in order to remove the resist component that may adhere to the processing chamber, it is better to clean the interior of the processing chamber with a solvent with a higher SP value than the first organic solvent contained in the processing liquid of the present invention after the processing is completed.

〔Resist composition〕 Next, as the resist composition used in combination with the treatment liquid of the present invention, for example, a so-called chemically amplified resist composition containing a resin, a photoacid generator and/or an acid diffusion control agent, etc., may also be A molecular inhibitor composition containing low-molecular phenol compounds instead of resins can also be a metal inhibitor composition containing metal oxide compounds, or a polymer main chain that is cut by exposure to reduce the molecular weight. Cut-off resist composition. The resist composition may be a negative resist composition or a positive resist composition. Hereinafter, the chemically amplified resist composition, which is one form of the resist composition that can be used in combination with the treatment liquid of the present invention, will be described in detail. In addition, hereinafter, the chemically amplified resist composition is also simply referred to as the resist composition.

＜Resin (A)＞ The resist composition includes a resin that is decomposed by the action of an acid to increase its polarity (hereinafter, also referred to as "acid decomposable resin" or "resin (A)"). That is, in the pattern forming method, typically, when an alkaline developer is used as the developer, a positive pattern is preferably formed, and when an organic developer is used as the developer, a negative pattern is preferably formed. The resin (A) usually contains a group that decomposes by the action of an acid to increase its polarity (hereinafter, also referred to as an "acid-decomposable group"), and preferably contains a repeating unit having an acid-decomposable group.

"Repeating Unit with Acid Decomposable Group" The acid-decomposable group refers to a group that decomposes by the action of an acid to generate a polar group. The acid-decomposable group preferably has a structure in which the polar group is protected by a leaving group that is detached by the action of an acid. That is, the resin (A) has a repeating unit having a group that decomposes by the action of an acid to generate a polar group. The resin having the repeating unit has an increased polarity due to the action of an acid, so that its solubility with respect to an alkali developer increases, and its solubility with respect to an organic solvent decreases. As the polar group, an alkali-soluble group is preferred. For example, a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group, a sulfonic acid group, a phosphoric acid group, a sulfonamide group, a sulfonamide group, (alkyl Sulfonyl) (alkyl carbonyl) methylene, (alkyl sulfonyl) (alkyl carbonyl) imidinyl, bis (alkylcarbonyl) methylene, bis (alkyl carbonyl) imidin , Bis(alkylsulfonyl)methylene, bis(alkylsulfonyl)imino, tris(alkylcarbonyl)methylene and tris(alkylsulfonyl)methylene and other acidic groups , And alcoholic hydroxyl groups. Among them, as the polar group, a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), or a sulfonic acid group is preferred.

Examples of the leaving group to be released by the action of an acid include groups represented by formulas (Y1) to (Y4). Formula (Y1): -C (Rx ₁ ) (Rx ₂ ) (Rx ₃ ) Formula (Y2): -C (=O) OC (Rx ₁ ) (Rx ₂ ) (Rx ₃ ) Formula (Y3): -C (R ₃₆ ) (R ₃₇ ) (OR ₃₈ ) Formula (Y4): -C (Rn) (H) (Ar)

In formula (Y1) and formula (Y2), Rx ₁ to Rx ₃ each independently represent an alkyl group (linear or branched) or cycloalkyl (monocyclic or polycyclic), alkenyl (linear or Branched) or aryl (monocyclic or polycyclic). In addition, when Rx ₁ to Rx ₃ are all alkyl groups (linear or branched), it is preferable that at least two of _{Rx 1} to Rx _{3 are methyl groups.} Wherein, Rx ₁ ~ Rx ₃ each independently represents a linear or branched alkyl group is preferred, Rx ₁ ~ Rx ₃ each independently represent a linear alkyl group is more preferred. Two of Rx ₁ to Rx ₃ may be bonded to form a monocyclic ring or a polycyclic ring. As _{the alkyl group of Rx 1} to Rx ₃ , alkyl groups having 1 to 5 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tertiary butyl are preferred. As Rx ₁ to Rx ₃ cycloalkyl, monocyclic cycloalkyl such as cyclopentyl and cyclohexyl, and polycyclic cycloalkane such as norbornyl, tetracyclodecyl, tetracyclododecyl, and adamantyl The base is better. As _{the aryl group of Rx 1} to Rx _3, an aryl group having 6 to 10 carbon atoms is preferred, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group. As _{the alkenyl group of Rx 1} to Rx ₃ , a vinyl group is preferred. As the ring formed by bonding two of _{Rx 1} to Rx _{3, a cycloalkyl group is preferred.} As _{a cycloalkyl formed by bonding two of Rx 1} to Rx ₃ , a monocyclic cycloalkyl such as cyclopentyl or cyclohexyl, or norbornyl, tetracyclodecyl, tetracyclododecyl or A polycyclic cycloalkyl group such as an adamantyl group is preferable, and a monocyclic cycloalkyl group having 5 to 6 carbon atoms is more preferable. The cycloalkyl group formed by bonding two of Rx ₁ to Rx ₃ may also be substituted with a group having a hetero atom such as an oxygen atom or a hetero atom such as a carbonyl group in the methylene group constituting the ring, or Replaced by vinylidene. In addition, these cycloalkyl groups may be substituted with ethylene groups in one or more of the ethylene groups constituting the cycloalkane alkane. The group represented by the formula (Y1) or the formula (Y2) is preferably such that Rx ₁ is a methyl group or an ethyl group, and Rx ₂ and Rx _{3 are} bonded to form the above-mentioned cycloalkyl group.

In formula (Y3), R ₃₆ to R ₃₈ each independently represent a hydrogen atom or a monovalent organic group. R ₃₇ and R ₃₈ may also be bonded to each other to form a ring. As a monovalent organic group, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, etc. are mentioned. R ₃₆ is also preferably a hydrogen atom. In addition, the above-mentioned alkyl group, cycloalkyl group, aryl group, and aralkyl group may also include a group having a hetero atom such as an oxygen atom and/or a hetero atom such as a carbonyl group. For example, the above-mentioned alkyl group, cycloalkyl group, aryl group, and aralkyl group may be substituted with a group having a hetero atom such as an oxygen atom and/or a hetero atom such as a carbonyl group in one or more of the methylene groups. In addition, R ₃₈ may be bonded to another substituent of the main chain of the repeating unit to form a ring. The _{group formed by bonding R 38} and another substituent of the main chain of the repeating unit to each other is preferably a methylene etc. alkylene group.

As the formula (Y3), a group represented by the following formula (Y3-1) is preferred.

[Chemical formula 2]

Here, L ₁ and L ₂ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a group formed by combining them (for example, a group formed by combining an alkyl group and an aryl group). M represents a single bond or a divalent linking group. Q represents an alkyl group that may contain a hetero atom, a cycloalkyl group that may contain a hetero atom, an aryl group that may contain a hetero atom, an amino group, an ammonium group, a mercapto group, a cyano group, an aldehyde group, or a combination of these groups ( For example, a group formed by combining an alkyl group and a cycloalkyl group). The alkyl group and the cycloalkyl group may be substituted with a group having a hetero atom such as an oxygen atom or a hetero atom such as a carbonyl group in a methylene group. In addition, it is preferable that one of L ₁ and L ₂ is a hydrogen atom, and the other is an alkyl group, a cycloalkyl group, an aryl group, or a combination of an alkylene group and an aryl group. At least two of Q, M, and L ₁ may be bonded to form a ring (preferably, a 5-membered or 6-membered ring). From the viewpoint of miniaturization of the pattern, L ₂ is preferably a secondary or tertiary alkyl group, and more preferably a tertiary alkyl group. Examples of the secondary alkyl group include isopropyl, cyclohexyl, or norbornyl, and examples of the tertiary alkyl group include tertiary butyl or adamantyl. In these aspects, Tg (Glass Transition Temperature) and activation energy become higher, so that the film strength can be ensured while rust can be suppressed.

In formula (Y4), Ar represents an aromatic ring group. Rn represents an alkyl group, a cycloalkyl group or an aryl group. Rn and Ar may also bond to each other to form a non-aromatic ring. Ar is more preferably an aryl group.

From the viewpoint of excellent acid decomposability of the repeating unit, when a non-aromatic ring is directly bonded to the polar group (or its residue) in the leaving group for protecting the polar group, the non-aromatic ring and the direct It is also preferable that the adjacent ring member atoms bonded to the above-mentioned polar group (or its residue) do not have a halogen atom such as a fluorine atom as a substituent.

The leaving group detached by the action of an acid can also be 2-cyclopropenyl having substituents (alkyl etc.) such as 3-methyl-2-cyclopropenyl and having such as 1,1,4 Cyclohexyl which is a substituent (alkyl etc.) such as 4-tetramethylcyclohexyl.

As the repeating unit having an acid-decomposable group, the repeating unit represented by the formula (A) is also preferable.

[Chemical formula 3]

L ₁ represents a divalent linking group that may have a fluorine atom or an iodine atom, and R ₁ represents an alkyl group that may have a hydrogen atom, a fluorine atom, an iodine atom, a fluorine atom, or an iodine atom, or an aromatic that may have a fluorine atom or an iodine atom. A group, R ₂ represents a leaving group which is released by the action of an acid and may have a fluorine atom or an iodine atom. Among them, _{at least one of L 1} , R ₁ and R ₂ has a fluorine atom or an iodine atom. L ₁ represents a divalent linking group which may have a fluorine atom or an iodine atom. Examples of the divalent linking group that may have a fluorine atom or an iodine atom include -CO-, -O-, -S-, -SO-, -SO ₂ -, and a hydrocarbon group that may have a fluorine atom or an iodine atom (for example, , Alkylene, cycloalkylene, alkenylene, arylalkylene, etc.) and linking groups formed by connecting a plurality of these. Among them, as L ₁ , -CO- or an alkylene group having an -arylene group-fluorine atom or an iodine atom- is preferable. As the aryl group, phenyl group is preferred. The alkylene group may be linear or branched. The carbon number of the alkylene group is not particularly limited, and 1-10 is preferred, and 1-3 is more preferred. The total number of fluorine atoms and iodine atoms contained in the alkylene group having a fluorine atom or an iodine atom is not particularly limited, and 2 or more is preferable, 2-10 is more preferable, and 3-6 is still more preferable.

R ₁ represents a hydrogen atom, a fluorine atom, an iodine atom, an alkyl group which may have a fluorine atom or an iodine atom, or an aryl group which may have a fluorine atom or an iodine atom. The alkyl group may be linear or branched. The carbon number of the alkyl group is not particularly limited, and 1-10 is preferred, and 1-3 is more preferred. The total number of fluorine atoms and iodine atoms contained in the alkyl group having a fluorine atom or an iodine atom is not particularly limited, and 1 or more is preferable, 1 to 5 are more preferable, and 1 to 3 are more preferable. The above-mentioned alkyl group may include heteroatoms such as oxygen atoms other than halogen atoms.

R ₂ represents a leaving group that is released by the action of an acid and may have a fluorine atom or an iodine atom. Among them, examples of the leaving group include groups represented by formulas (Z1) to (Z4). Formula (Z1): -C (Rx ₁₁ ) (Rx ₁₂ ) (Rx ₁₃ ) Formula (Z2): -C (=O) OC (Rx ₁₁ ) (Rx ₁₂ ) (Rx ₁₃ ) Formula (Z3): -C (R ₁₃₆ ) (R ₁₃₇ ) (OR ₁₃₈ ) Formula (Z4): -C (Rn ₁ ) (H) (Ar ₁ )

In the formulas (Z1) and (Z2), Rx ₁₁ to Rx ₁₃ each independently represent an alkyl group (linear or branched) that may have a fluorine atom or an iodine atom, and a cycloalkyl group that may have a fluorine atom or an iodine atom (Monocyclic or polycyclic), an alkenyl group (linear or branched) which may have a fluorine atom or an iodine atom, or an aryl group which may have a fluorine atom or an iodine atom (monocyclic or polycyclic). In addition, when Rx ₁₁ to Rx ₁₃ are all alkyl groups (linear or branched), it is preferred that at least two of _{Rx 11} to Rx _{13 are methyl groups.} Rx ₁₁ to Rx _{13 are the same as Rx 1} to Rx _{3 in} (Y1) and (Y2) above, except that they may have a fluorine atom or an iodine atom, and have the same definitions as alkyl, cycloalkyl, alkenyl and aryl groups And the preferred range is the same.

In formula (Z3), R ₁₃₆ to R ₁₃₈ each independently represent a hydrogen atom or a monovalent organic group which may have a fluorine atom or an iodine atom. R ₁₃₇ and R ₁₃₈ may also be bonded to each other to form a ring. Examples of the monovalent organic group which may have a fluorine atom or an iodine atom include an alkyl group which may have a fluorine atom or an iodine atom, a cycloalkyl group which may have a fluorine atom or an iodine atom, and an aromatic group which may have a fluorine atom or an iodine atom. A group, an aralkyl group which may have a fluorine atom or an iodine atom, and a group formed by combining them (for example, a group formed by combining an alkyl group and a cycloalkyl group). In addition, the alkyl group, cycloalkyl group, aryl group, and aralkyl group may contain heteroatoms such as oxygen atoms in addition to fluorine atoms and iodine atoms. That is, the aforementioned alkyl group, cycloalkyl group, aryl group, and aralkyl group may be substituted with a group having a hetero atom such as an oxygen atom or a hetero atom such as a carbonyl group in a methylene group. In addition, R ₁₃₈ may be bonded to another substituent of the main chain of the repeating unit to form a ring. In this case, _{the group formed by bonding R 138} and another substituent of the main chain of the repeating unit to each other is preferably a methylene etc. alkylene group.

As the formula (Z3), a group represented by the following formula (Z3-1) is preferred.

[Chemical formula 4]

Here, L ₁₁ and L ₁₂ each independently represent a hydrogen atom; an alkyl group that may have a hetero atom selected from the group including a fluorine atom, an iodine atom, and an oxygen atom; may have an alkyl group selected from a group including a fluorine atom, an iodine atom, and Cycloalkyl groups of heteroatoms in the group of oxygen atoms; aryl groups that may have heteroatoms selected from the group including fluorine atoms, iodine atoms, and oxygen atoms; or groups formed by combining them (for example, The combination may have a group consisting of an alkyl group and a cycloalkyl group selected from the group consisting of a fluorine atom, an iodine atom, and an oxygen atom). M ₁ represents a single bond or a divalent linking group. Q ₁ represents an alkyl group which may have a hetero atom selected from the group including a fluorine atom, an iodine atom, and an oxygen atom; a cycloalkane which may have a hetero atom selected from the group including a fluorine atom, an iodine atom, and an oxygen atom A group; an aryl group selected from the group including a fluorine atom, an iodine atom and an oxygen atom; an amine group; an ammonium group; a mercapto group; a cyano group; an aldehyde group; A group formed by a combination of an alkyl group and a cycloalkyl group selected from the group consisting of a fluorine atom, an iodine atom and an oxygen atom).

In formula (Z4), Ar ₁ represents an aromatic ring group which may have a fluorine atom or an iodine atom. Rn ₁ represents an alkyl group which may have a fluorine atom or an iodine atom, a cycloalkyl group which may have a fluorine atom or an iodine atom, or an aryl group which may have a fluorine atom or an iodine atom. Rn ₁ and Ar ₁ may also be bonded to each other to form a non-aromatic ring.

As the repeating unit having an acid-decomposable group, the repeating unit represented by the general formula (AI) is also preferable.

[Chemical formula 5]

In the general formula (AI), Xa ₁ represents a hydrogen atom or an alkyl group which may have a substituent. T represents a single bond or a divalent linking group. Rx ₁ to Rx ₃ each independently represent alkyl (linear or branched), cycloalkyl (monocyclic or polycyclic), alkenyl (linear or branched), or aromatic (monocyclic or polycyclic) Ring) base. Among them, when Rx ₁ to Rx ₃ are all alkyl groups (linear or branched), it is preferred that at least two of _{Rx 1} to Rx _{3 are methyl groups.} Two of Rx ₁ to Rx ₃ may be bonded to form a monocyclic or polycyclic ring (monocyclic or polycyclic cycloalkyl group, etc.).

Examples of the optionally substituted alkyl group represented by Xa ₁ include a methyl group or a group represented by _{-CH 2} -R _11. R ₁₁ represents a halogen atom (fluorine atom, etc.), a hydroxyl group, or a monovalent organic group. For example, an alkyl group with 5 or less carbons which may be substituted by a halogen atom, and an acyl group with 5 or less carbons which may be substituted by a halogen atom are mentioned. A group and an alkoxy group having 5 or less carbon atoms which may be substituted with a halogen atom, an alkyl group having 3 or less carbon atoms is preferable, and a methyl group is more preferable. As Xa ₁ , a hydrogen atom, a methyl group, a trifluoromethyl group or a hydroxymethyl group is preferable.

Examples of the divalent linking group of T include an alkylene group, an aromatic ring group, a -COO-Rt- group, and a -O-Rt- group. In the formula, Rt represents an alkylene group or a cycloalkylene group. Preferably, T is a single bond or -COO-Rt- group. When T represents a -COO-Rt- group, Rt is preferably an alkylene group having 1 to 5 carbons, and a -CH ₂ -group, -(CH ₂ ) ₂ -group or -(CH ₂ ) ₃ -group is more preferred good.

As _{the alkyl group of Rx 1} to Rx ₃ , alkyl groups having 1 to 4 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tertiary butyl are preferred. As Rx ₁ to Rx ₃ cycloalkyl, monocyclic cycloalkyl such as cyclopentyl and cyclohexyl, or polycyclic ring such as norbornyl, tetracyclodecyl, tetracyclododecyl, and adamantyl Alkyl is preferred. As _{the aryl group of Rx 1} to Rx _3, an aryl group having 6 to 10 carbon atoms is preferred, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group. As _{the alkenyl group of Rx 1} to Rx ₃ , a vinyl group is preferred. As _{the cycloalkyl formed by bonding two of Rx 1} to Rx ₃ , monocyclic cycloalkyls such as cyclopentyl and cyclohexyl are preferred. In addition, norbornyl, tetracyclodecyl, and tetracycloalkyl are preferred. Polycyclic cycloalkyl groups such as cyclododecyl and adamantyl are preferred. Among them, a monocyclic cycloalkyl group having 5 to 6 carbon atoms is preferred. The cycloalkyl group formed by bonding two of Rx ₁ to Rx ₃ may also be substituted with a group having a hetero atom such as an oxygen atom or a hetero atom such as a carbonyl group in the methylene group constituting the ring, or Replaced by vinylidene. In addition, these cycloalkyl groups may be substituted with ethylene groups in one or more of the ethylene groups constituting the cycloalkane alkane. Among the repeating units represented by the general formula (AI), for example, Rx ₁ is a methyl group or an ethyl group, and Rx ₂ and Rx _{3 are} bonded to form the above-mentioned cycloalkyl group.

When each of the above groups has a substituent, examples of the substituent include an alkyl group (carbon number 1 to 4), a halogen atom, a hydroxyl group, an alkoxy group (carbon number 1 to 4), a carboxyl group, and an alkoxycarbonyl group. (Carbon number 2～6) and so on. The number of carbon atoms in the substituent is preferably 8 or less.

The repeating unit represented by the general formula (AI) is preferably an acid-decomposable (meth)acrylate tertiary alkyl ester repeating unit (where Xa ₁ represents a hydrogen atom or a methyl group and T represents a single bond) .

The content of the repeating unit having an acid-decomposable group is preferably 15 mol% or more with respect to the total repeating units in the resin (A), more preferably 20 mol% or more, and even more preferably 25 mol% or more, More than 30 mol% is particularly good. There is no particular limitation on the upper limit, but 90 mol% or less is preferable, 80 mol% or less is more preferable, and 70 mol% is still more preferable.

Although the specific example of the repeating unit which has an acid-decomposable group is shown below, this invention is not limited to this. In addition, in the formula, Xa ₁ represents any one of H, CH ₃ , CF ₃ and CH ₂ OH, and Rxa and Rxb represent a linear or branched alkyl group having 1 to 5 carbon atoms, respectively.

[Chemical formula 6]

[Chemical formula 7]

[Chemical formula 8]

[Chemical formula 9]

[Chemical formula 10]

The resin (A) may contain repeating units other than the above repeating units. For example, the resin (A) may also include at least one repeating unit selected from the group including the following A group and/or at least one repeating unit selected from the group including the following B group. Group A: A group that includes the following repeating units (20) ~ (29). (20) Repeating unit with acid group mentioned later (21) Repeating unit with fluorine atom or iodine atom mentioned later (22) The repeating unit having a lactone group, a sultone group or a carbonate group mentioned later (23) The repeating unit with photoacid generating group mentioned later (24) The repeating unit represented by the following general formula (V-1) or the following general formula (V-2) (25) Repeating unit represented by formula (A) described later (26) Repeating unit represented by formula (B) described later (27) Repeating unit represented by formula (C) described later (28) Repeating unit represented by formula (D) described later (29) Repeating unit represented by formula (E) described later Group B: A group that includes the following repeating units (30) to (32). (30) The following repeating unit having at least one group selected from lactone group, sultone group, carbonate group, hydroxyl group, cyano group and alkali-soluble group (31) The repeating unit that has an alicyclic hydrocarbon structure and does not show acid decomposability described later (32) The repeating unit represented by the general formula (III) that does not have any one of a hydroxyl group and a cyano group described later

When the resist composition is used for EUV exposure or electron beam exposure, it is preferable that the resin (A) has at least one repeating unit selected from the group including the above A group. Moreover, when the resist composition is used for EUV exposure applications or electron beam exposure applications, it is also preferable that the resin (A) contains at least one of fluorine atoms and iodine atoms. When the resin (A) contains both a fluorine atom and an iodine atom, the resin (A) may have a repeating unit including both a fluorine atom and an iodine atom, and the resin (A) may also include a repeating unit having a fluorine atom and Both of the repeating units containing iodine atoms. Moreover, when the resist composition is used for EUV exposure or electron beam exposure, it is also preferable that the resin (A) has a repeating unit having an aromatic group. When the resist composition is used for ArF exposure purposes, the resin (A) preferably has at least one repeating unit selected from the group including the above-mentioned B group. Moreover, when the resist composition is used for ArF exposure purposes, it is preferable that the resin (A) does not contain any one of a fluorine atom and a silica atom. Moreover, when the composition is used for ArF purposes, it is preferable that the resin (A) does not have an aromatic group.

"Repeating unit having an acid group" The resin (A) may have a repeating unit having an acid group. As the acid group, an acid group having a pKa of 13 or less is preferable. As the acid group, for example, a carboxyl group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), a sulfonic acid group, a sulfonamide group, or an isopropanol group are preferable. In addition, the above-mentioned hexafluoroisopropanol group may be one or more (preferably 1 to 2) of the fluorine atoms substituted by groups other than the fluorine atoms (alkoxycarbonyl groups, etc.). The thus formed -C(CF ₃ )(OH)-CF ₂ -is preferable as the acid group. In addition, one or more of the fluorine atoms may be substituted with a group other than the fluorine atom to form a _{ring containing -C(CF 3} )(OH)-CF ₂ -. The repeating unit having an acid group is a repeating unit having a structure in which a polar group is detached by the action of the above-mentioned acid, and a repeating unit that is different from the repeating unit having a lactone group, a sultone group, or a carbonate group described later The unit is better.

The repeating unit having an acid group may also have a fluorine atom or an iodine atom.

As the repeating unit having an acid group, the repeating unit represented by formula (B) is preferred.

[Chemical formula 11]

R ₃ represents a hydrogen atom or a monovalent organic group which may have a fluorine atom or an iodine atom. As the monovalent organic group which may have a fluorine atom or an iodine atom, a group _{represented by -L 4} -R ₈ is preferred. L ₄ represents a single bond or an ester group. Examples of R ₈ include an alkyl group which may have a fluorine atom or an iodine atom, a cycloalkyl group which may have a fluorine atom or an iodine atom, an aryl group which may have a fluorine atom or an iodine atom, or a combination of these groups. .

R ₄ and R ₅ each independently represent a hydrogen atom, a fluorine atom, an iodine atom, or an alkyl group which may have a fluorine atom or an iodine atom.

L ₂ represents a single bond or an ester group. L ₃ represents an (n+m+1)-valent aromatic hydrocarbon ring group or an (n+m+1)-valent alicyclic hydrocarbon ring group. Examples of the aromatic hydrocarbon ring group include a benzene ring group and a naphthalene ring group. The alicyclic hydrocarbon ring group may be a monocyclic ring or a polycyclic ring group. For example, a cycloalkyl ring group may be mentioned. R ₆ represents a hydroxyl group or a fluorinated alcohol group (preferably a hexafluoroisopropanol group). In addition, when R ₆ is a hydroxyl group, L ₃ is preferably an aromatic hydrocarbon ring group having a valence of (n+m+1). R ₇ represents a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. m represents an integer of 1 or more. It is preferable that m is an integer of 1-3, and an integer of 1-2 is more preferable. n represents an integer of 0 or more. Preferably, n is an integer of 1 to 4. In addition, (n+m+1) is preferably an integer of 1 to 5.

As the repeating unit having an acid group, the repeating unit represented by the following general formula (I) is also preferable.

[Chemical formula 12]

In the general formula (I), R ₄₁ , R ₄₂ and R ₄₃ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group, or an alkoxycarbonyl group. Among them, R ₄₂ may be _{bonded to Ar 4} to form a ring. In this case, R ₄₂ represents a single bond or an alkylene group. X ₄ represents a single bond, -COO- or -CONR ₆₄ -, and R ₆₄ represents a hydrogen atom or an alkyl group. L ₄ represents a single bond or an alkylene group. Ar ₄ represents an (n+1)-valent aromatic ring group, and _{when it is bonded to R 42} to form a ring, it represents an (n+2)-valent aromatic ring group. n represents an integer of 1-5.

_{As the alkyl group of R 41} , R ₄₂ and R ₄₃ in the general formula (I), methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, hexyl, 2-ethylhexyl, Alkyl groups with 20 or less carbon atoms, such as octyl and dodecyl, are more preferable, alkyl groups with 8 or less carbon atoms, and alkyl groups with 3 or less carbon atoms are more preferable.

_{The cycloalkyl group of R 41} , R ₄₂ and R ₄₃ in the general formula (I) may be a monocyclic type or a polycyclic type. Among them, monocyclic cycloalkyl groups having 3 to 8 carbon atoms such as cyclopropyl, cyclopentyl, and cyclohexyl are preferred. _{Examples of the halogen atom of R 41} , R ₄₂ and R 43 in the general formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferred. _{The alkyl group contained in the alkoxycarbonyl group of R 41} , R ₄₂ and R ₄₃ in the general formula (I) is preferably the same as the alkyl group in the above-mentioned R ₄₁ , R ₄₂ , and R _43.

As preferred substituents in each of the above groups, for example, alkyl groups, cycloalkyl groups, aryl groups, amino groups, amide groups, ureido groups, urethane groups, hydroxyl groups, carboxyl groups, and halogens can be cited. Atom, alkoxy group, thioether group, acyl group, acyloxy group, alkoxycarbonyl group, cyano group and nitro group. The carbon number of the substituent is preferably 8 or less.

Ar ₄ represents an (n+1)-valent aromatic ring group. The divalent aromatic ring group when n is 1, for example, arylene groups having 6 to 18 carbon atoms, such as phenylene, phenylene, methylnaphthyl, and anthrylene, or containing thiophene ring, furan ring, and pyrrole. Divalent aromatic ring group of heterocycles such as ring, benzothiophene ring, benzofuran ring, benzopyrrole ring, tri-ring, imidazole ring, benzimidazole ring, triazole ring, thiadiazole ring and thiazole ring For better. In addition, the above-mentioned aromatic ring group may have a substituent.

As a specific example of the (n+1)-valent aromatic ring group when n is an integer of 2 or more, there can be mentioned the removal of (n-1) arbitrary hydrogen atoms from the above-mentioned specific examples of the divalent aromatic ring group The resulting group is preferred. The (n+1)-valent aromatic ring group may further have a substituent.

Examples of substituents that the above-mentioned alkyl group, cycloalkyl group, alkoxycarbonyl group, alkylene group, and (n+1)-valent aromatic ring group may have include, for example, R ₄₁ in the general formula (I), Alkoxy groups such as alkyl, methoxy, ethoxy, hydroxyethoxy, propoxy, hydroxypropoxy and butoxy; aryl groups such as phenyl, etc. mentioned in R ₄₂ and R _43. Examples of the _{alkyl group of R 64 in -CONR 64-} (R ₆₄ represents a hydrogen atom or an alkyl group) represented by X ₄ include methyl, ethyl, propyl, isopropyl, n-butyl, and second Alkyl groups with 20 or less carbon atoms, such as butyl, hexyl, 2-ethylhexyl, octyl, and dodecyl, are preferably alkyl groups with 8 or less carbon atoms. As X ₄ , a single bond, -COO- or -CONH- is preferred, and a single bond or -COO- is more preferred.

As the _{alkylene group in L 4} , alkylene groups having 1 to 8 carbon atoms such as methylene, ethylene, propyl, butyl, hexylene, and octylene are preferred. As Ar ₄ , an aromatic ring group having 6 to 18 carbon atoms is preferred, and a benzene ring group, a naphthalene ring group, and a biphenyl ring group are more preferred. It is preferable that the repeating unit represented by the general formula (I) has a hydroxystyrene structure. That is, Ar ₄ is preferably a benzene ring group.

As the repeating unit represented by the above general formula (I), a repeating unit represented by the following general formula (1) is preferred.

[Chemical formula 13]

In the general formula (1), A represents a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom or a cyano group. R represents a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, an aralkyl group, an alkoxy group, an alkylcarbonyloxy group, an alkylsulfonyloxy group, an alkoxycarbonyl group or an aryloxycarbonyl group, having The plural may be the same or different from each other. When there are a plurality of Rs, they can also form a ring together. As R, a hydrogen atom is preferred. a represents an integer of 1-3. b represents an integer from 0 to (5-a).

Among them, the resin contained in the resist composition preferably has a hydroxystyrene-based repeating unit. As the hydroxystyrene-based repeating unit, for example, a repeating unit in which A represents a hydrogen atom in the general formula (1) can be given.

Hereinafter, the repeating unit having an acid group is exemplified. In the formula, a represents 1 or 2.

[Chemical formula 14]

[Chemical formula 15]

[Chemical formula 16]

In addition, among the above repeating units, repeating units specifically described below are preferred. In the formula, R represents a hydrogen atom or a methyl group, and a represents 2 or 3.

[Chemical formula 17]

[Chemical formula 18]

The content of the repeating unit having an acid group (preferably a hydroxystyrene-based repeating unit) relative to all repeating units in the resin (A) is preferably 5 mol% or more, and more preferably 10 mol% or more. There is no particular limitation on the upper limit, but 50 mol% or less is preferable, 45 mol% or less is more preferable, and 40 mol% or less is more preferable.

"Repeating unit with fluorine atom or iodine atom" The resin (A) may have a repeating unit having a fluorine atom or an iodine atom in addition to the above-mentioned "repeating unit having an acid-decomposable group" and "repeating unit having an acid group". In addition, the "repeating unit having a fluorine atom or an iodine atom" mentioned here, the "repeating unit having a lactone group, a sultone group, or a carbonate group" and "repeating unit having a photoacid generating group" mentioned later belong to It is preferable that other types of repeating units in the A group are different.

As the repeating unit having a fluorine atom or an iodine atom, the repeating unit represented by the formula (C) is preferred.

[Chemical formula 19]

L ₅ represents a single bond or an ester group. R ₉ represents a hydrogen atom or an alkyl group which may have a fluorine atom or an iodine atom. R ₁₀ represents a hydrogen atom, an alkyl group which may have a fluorine atom or an iodine atom, a cycloalkyl group which may have a fluorine atom or an iodine atom, an aryl group which may have a fluorine atom or an iodine atom, or a combination of these groups.

The repeating unit having a fluorine atom or an iodine atom is illustrated below.

[Chemical formula 20]

The content of the repeating unit having a fluorine atom or an iodine atom relative to the total repeating units in the resin (A) is preferably 0 mol% or more, more preferably 5 mol% or more, and more preferably 10 mol% or more . Moreover, as the upper limit, 50 mol% or less is preferable, 45 mol% or less is more preferable, and 40 mol% or less is more preferable. In addition, as mentioned above, the repeating unit having a fluorine atom or an iodine atom does not include the "repeating unit having an acid-decomposable group" and the "repeating unit having an acid group", so the above-mentioned repeating unit having a fluorine atom or an iodine atom The content also means the content of the repeating unit having a fluorine atom or an iodine atom other than "repeating unit having an acid-decomposable group" and "repeating unit having an acid group".

In the repeating unit of the resin (A), the total content of the repeating unit containing at least one of fluorine atoms and iodine atoms relative to the total repeating units of the resin (A) is preferably 20 mol% or more, 30 mol% The above is more preferable, and 40 mol% or more is even more preferable. The upper limit is not particularly limited, and is, for example, 100 mol% or less. In addition, as a repeating unit containing at least one of a fluorine atom and an iodine atom, for example, a repeating unit having a fluorine atom or an iodine atom and an acid-decomposable group, and a repeating unit having a fluorine atom or an iodine atom and an acid group can be mentioned. Repeating unit and repeating unit having fluorine atom or iodine atom.

"Repeating unit with lactone group, sultone group or carbonate group" The resin (A) may also have a repeating unit having at least one selected from the group consisting of a lactone group, a sultone group, and a carbonate group (hereinafter, also collectively referred to as "having a lactone group, a sultone group Or the repeating unit of the carbonate group"). It is also preferable that the repeating unit having a lactone group, a sultone group, or a carbonate group does not have an acid group such as a hexafluoropropanol group.

As a lactone group or a sultone group, what is necessary is just to have a lactone structure or a sultone structure. Preferably, the lactone structure or the sultone structure is a 5- to 7-membered cyclic lactone structure or a 5- to 7-membered cyclic sultone structure. Among them, in the form of forming a bicyclic structure or a spiro ring structure, the 5- to 7-membered ring lactone structure is fused with other ring structures, or in the form of forming a bicyclic structure or a spiro ring structure in the form of a 5- to 7-membered ring sultone It is better to have other ring structures condensed in structure. The resin (A) preferably has a repeating unit having a lactone structure represented by any one of the following general formulas (LC1-1) to (LC1-21) or the following general formula (SL1- 1) A lactone group or a sultone group obtained by removing one or more hydrogen atoms from the ring member atoms of the sultone structure represented by any one of to (SL1-3). In addition, the lactone group or the sultone group may be directly bonded to the main chain. For example, the ring member atoms of the lactone group or the sultone group may also constitute the main chain of the resin (A).

[Chemical formula 21]

The aforementioned lactone structure or sultone structure part may have a substituent (Rb ₂ ). Preferred substituents (Rb ₂ ) include alkyl groups having 1 to 8 carbons, cycloalkyl groups having 4 to 7 carbons, alkoxy groups having 1 to 8 carbons, and alkyl groups having 1 to 8 carbons. Oxycarbonyl group, carboxyl group, halogen atom, hydroxyl group, cyano group, acid decomposable group, etc. n2 represents an integer of 0-4. When n2 is 2 or more, the presence of a plurality of Rb ₂ may not be the same, and the presence of a plurality of Rb ₂ may be bonded to each other to form a ring.

As having a lactone structure represented by any one of the general formulas (LC1-1) to (LC1-21) or a sultone represented by any one of the general formulas (SL1-1) to (SL1-3) Examples of the repeating unit of the group of the structure include repeating units represented by the following general formula (AI).

[Chemical formula 22]

In the general formula (AI), Rb ₀ represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. Examples _{of preferable substituents that the alkyl group of Rb 0} may have include a hydroxyl group and a halogen atom. Examples _{of the halogen atom of Rb 0} include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Rb ₀ is preferably a hydrogen atom or a methyl group. Ab represents a divalent linking group having a single bond, an alkylene group, a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, a carboxyl group, or a combination of these divalent groups. Among them, a single bond or a linking group represented by _{-Ab 1} -CO _{2-is preferred.} Ab ₁ is a linear or branched alkylene group, or a monocyclic or polycyclic cycloalkylene group. Methylene, ethylidene, cyclohexylene, adamanthenyl or norbornanyl are more good. V represents a group obtained by removing one hydrogen atom from the ring member atom of the lactone structure represented by any one of the general formulas (LC1-1) to (LC1-21), or from the general formula (SL1-1 ) ~ (SL1-3) is a group formed by removing one hydrogen atom from the ring member atom of the sultone structure represented by any one of (SL1-3).

When an optical isomer is present in the repeating unit having a lactone group or a sultone group, any optical isomer may be used. In addition, one kind of optical isomer may be used alone, or plural kinds of optical isomers may be used in combination. When mainly using one optical isomer, the optical purity (ee) is preferably 90 or more, and more preferably 95 or more.

As the carbonate group, a cyclic carbonate group is preferred. As the repeating unit having a cyclic carbonate group, a repeating unit represented by the following general formula (A-1) is preferred.

[Chemical formula 23]

In the general formula (A-1), R _A ¹ represents a hydrogen atom, a halogen atom, or a monovalent organic group (preferably a methyl group). n represents an integer of 0 or more. R _A ² represents a substituent. When n is 2 or more, a plurality of R _A ² may be the same or different. A represents a single bond or a divalent linking group. As the above-mentioned divalent linking group, an alkylene group, a divalent linking group having a monocyclic or polycyclic alicyclic hydrocarbon structure, an ether group, an ester group, a carbonyl group, a carboxyl group, or a combination thereof The group is preferred. Z represents an atomic group that forms a monocyclic or polycyclic ring together with the group represented by -O-CO-O- in the formula.

The following examples show repeating units having a lactone group, a sultone group, or a carbonate group.

[Chemical formula 24]

[Chemical formula 25]

[Chemical formula 26]

The content of the repeating unit having a lactone group, a sultone group, or a carbonate group is preferably 1 mol% or more with respect to the total repeating units in the resin (A), and more preferably 5 mol% or more. In addition, the upper limit is not particularly limited, but 65 mol% or less is preferable, 30 mol% or less is more preferable, 25 mol% or less is more preferable, and 20 mol% or less is particularly preferable.

"Repeating unit with photoacid generating group" As a repeating unit other than the above, the resin (A) may have a repeating unit having a group that generates an acid by irradiation with actinic rays or radiation (hereinafter, also referred to as a "photoacid generating group"). In this case, it can be considered that the repeating unit having the photoacid generating group corresponds to a compound that generates acid by irradiation with actinic rays or radiation described later (hereinafter, also referred to as "photoacid generator"). As such a repeating unit, for example, a repeating unit represented by the following general formula (4) can be given.

[Chemical formula 27]

R ⁴¹ represents a hydrogen atom or a methyl group. L ⁴¹ represents a single bond or a divalent linking group. L ⁴² represents a divalent linking group. R ⁴⁰ represents a structural site that decomposes by irradiation with actinic rays or radiation to generate acid in the side chain.

The repeating unit having a photoacid generating group is illustrated below.

[Chemical formula 28]

[Chemical formula 29]

In addition, as the repeating unit represented by the general formula (4), for example, the repeating unit described in paragraphs [0094] to [0105] of JP 2014-041327 A can be cited.

The content of the repeating unit having a photoacid generating group is preferably 1 mol% or more with respect to the total repeating units in the resin (A), and more preferably 5 mol% or more. Moreover, as the upper limit, 40 mol% or less is preferable, 35 mol% or less is more preferable, and 30 mol% or less is more preferable.

"Repeating unit represented by general formula (V-1) or the following general formula (V-2)" The resin (A) may have a repeating unit represented by the following general formula (V-1) or the following general formula (V-2). The repeating unit represented by the following general formula (V-1) and the following general formula (V-2) is preferably a repeating unit different from the above-mentioned repeating unit.

[Chemical formula 30]

In the formula, R ₆ and R ₇ each independently represent a hydrogen atom, a hydroxyl group, an alkyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR or -COOR: R It is an alkyl group having 1 to 6 carbons or a fluorinated alkyl group) or a carboxyl group. As the alkyl group, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms is preferred. n ₃ represents an integer of 0-6. n ₄ represents an integer of 0-4. X ₄ is a methylene group, an oxygen atom or a sulfur atom. The following exemplifies the repeating unit represented by the general formula (V-1) or (V-2).

[Chemical formula 31]

"Repeating Units Used to Reduce the Mobility of the Main Chain" From the viewpoint of suppressing excessive diffusion of the generated acid or pattern collapse during development, the glass transition temperature (Tg) of the resin (A) is preferably higher. The Tg is preferably greater than 90°C, more preferably greater than 100°C, more preferably greater than 110°C, and particularly preferably greater than 125°C. In addition, an excessive increase in Tg will result in a decrease in the rate of dissolution in the developer. Therefore, the Tg is preferably 400° C. or less, and more preferably 350° C. or less. In addition, in this specification, the glass transition temperature (Tg) of the polymer, such as resin (A), is calculated by the following method. First, the Tg of a homopolymer including only each repeating unit contained in the polymer is separately calculated by the Bicerano method. Hereinafter, the calculated Tg is referred to as "Tg of the repeating unit". Next, the mass ratio (%) of each repeating unit relative to the total repeating unit in the polymer is calculated. Next, the Tg at each mass ratio is calculated using the formula of Fox (described in Materials Letters 62 (2008) 3152, etc.), and these are added together and used as the Tg (°C) of the polymer. The Bicerano method is described in Prediction of polymer properties, Marcel Dekker Inc, New York (1993), etc. In addition, the calculation of Tg based on the Bicerano method can be performed using MDL Polymer (MDL Information Systems, Inc.), a software for calculating physical properties of polymers.

In order to increase the Tg of the resin (A) (it is preferable to set the Tg to exceed 90° C.), it is preferable to reduce the mobility of the main chain of the resin (A). As a method of reducing the mobility of the main chain of the resin (A), the following methods (a) to (e) can be cited. (A) Introduce bulky substituents in the main chain (B) Introduce multiple substituents in the main chain (C) Introduce substituents that cause interaction between resins (A) near the main chain (D) The main chain forming the ring structure (E) Connect the ring structure to the main chain In addition, the resin (A) preferably has a repeating unit having a homopolymer Tg of 130°C or higher. In addition, the type of repeating unit having a Tg of 130°C or higher for the homopolymer is not particularly limited, as long as it is a repeating unit having a Tg of 130°C or higher for the homopolymer calculated by the Bicerano method. In addition, depending on the type of the functional group in the repeating unit represented by the formula (A) to the formula (E) described later, the homopolymer corresponds to a repeating unit having a Tg of 130° C. or more.

(Repeating unit represented by formula (A)) As an example of the specific realization of the above (a), a method of introducing the repeating unit represented by the formula (A) into the resin (A) can be cited.

[Chemical formula 32]

In the formula _(A), R A represents a group having a polycyclic structures. R _x represents a hydrogen atom, a methyl group, or an ethyl group. A group with a polycyclic structure is a group with a plurality of ring structures, and the plurality of ring structures may or may not be fused. As specific examples of the repeating unit represented by the formula (A), the following repeating units can be given.

[Chemical formula 33]

[Chemical formula 34]

[Chemical formula 35]

In the above formula, R represents a hydrogen atom, a methyl group or an ethyl group. Ra represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR'"Or-COOR"':R'" is an alkyl group having 1 to 20 carbons or a fluorinated alkyl group) or a carboxyl group. In addition, the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group, and the alkenyl group may each have a substituent. In addition, the hydrogen atom bonded to the carbon atom in the group represented by Ra may be substituted with a fluorine atom or an iodine atom. In addition, R'and R'' each independently represent an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, and a halogen atom. , Ester group (-OCOR''' or -COOR''': R''' is an alkyl group with 1 to 20 carbons or a fluorinated alkyl group) or a carboxyl group. In addition, the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group, and the alkenyl group may each have a substituent. In addition, the hydrogen atoms bonded to the carbon atoms in the groups represented by R′ and R″ may be substituted with fluorine atoms or iodine atoms. L represents a single bond or a divalent linking group. As the divalent linking group, for example, -COO-, -CO-, -O-, -S-, -SO-, -SO ₂ -, alkylene, cycloalkylene, alkenylene and A plurality of these connecting bases etc. are connected. m and n each independently represent an integer of 0 or more. The upper limit of m and n is not particularly limited, and is often 2 or less, and more is 1 or less.

(Repeating unit represented by formula (B)) As an example of the specific realization of the above (b), a method of introducing the repeating unit represented by the formula (B) into the resin (A) can be cited.

[Chemical formula 36]

In formula (B), R _b1 to R _b4 each independently represent a hydrogen atom or an organic group, and at least two of _{R b1} to R _{b4 represent an organic group.} In addition, when at least one of the organic groups is a group in which a ring structure is directly connected to the main chain of the repeating unit, the types of other organic groups are not particularly limited. In addition, when none of the organic groups is a group with a ring structure directly connected to the main chain of the repeating unit, at least 2 or more of the organic groups are 3 or more constituent atoms other than hydrogen atoms的Substituents.

As specific examples of the repeating unit represented by the formula (B), the following repeating units can be given.

[Chemical formula 37]

In the above formula, R each independently represents a hydrogen atom or an organic group. Examples of the organic group include organic groups such as an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group which may also have a substituent. R'each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester group (-OCOR "Or -COOR": R" is an alkyl group having 1 to 20 carbons or a fluorinated alkyl group) or a carboxyl group. In addition, the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group, and the alkenyl group may each have a substituent. In addition, the hydrogen atom bonded to the carbon atom in the group represented by R'may be substituted with a fluorine atom or an iodine atom. m represents an integer of 0 or more. The upper limit of m is not particularly limited, and it is often 2 or less, and more is 1 or less.

(Repeating unit represented by formula (C)) As an example of the specific realization of the above (c), a method of introducing the repeating unit represented by the formula (C) into the resin (A) can be cited.

[Chemical formula 38]

In formula (C), R _c1 to R _c4 each independently represent a hydrogen atom or an organic group, _{and at least one of R c1} to R _c4 is a group having a hydrogen-bonding hydrogen atom within 3 atoms of the main chain carbon group. Among them, in order to cause the interaction between the main chains of the resin (A), a hydrogen atom having a hydrogen bond within 2 atoms (closer to the main chain side) is preferred.

As specific examples of the repeating unit represented by the formula (C), the following repeating units can be given.

[Chemical formula 39]

In the above formula, R represents an organic group. Examples of the organic group include optionally substituted alkyl, cycloalkyl, aryl, aralkyl, alkenyl and ester groups (-OCOR or -COOR: R is an alkyl group with 1 to 20 carbon atoms or fluorine化alkyl) and so on. R'represents a hydrogen atom or an organic group. Examples of the organic group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and an alkenyl group. In addition, the hydrogen atom in the organic group may be substituted with a fluorine atom or an iodine atom.

(Repeating unit represented by formula (D)) As an example of the specific realization of the above (d), a method of introducing the repeating unit represented by formula (D) into the resin (A) can be cited.

[Chemical formula 40]

In formula (D), "cylic" represents a group formed by forming a main chain with a cyclic structure. The number of atoms constituting the ring is not particularly limited.

As specific examples of the repeating unit represented by the formula (D), the following repeating units can be given.

[Chemical formula 41]

In the above formula, R each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, and a halogen atom , Ester group (-OCOR" or -COOR": R" is an alkyl or fluorinated alkyl group with 1 to 20 carbons) or a carboxyl group. In addition, the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group, and the alkenyl group may each have a substituent. In addition, the hydrogen atom bonded to the carbon atom in the group represented by R may be substituted with a fluorine atom or an iodine atom. In the above formula, R'each independently represents an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, an ester Group (-OCOR" or -COOR": R" is an alkyl group or fluorinated alkyl group having 1 to 20 carbons) or a carboxyl group. In addition, the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group, and the alkenyl group may each have a substituent. In addition, the hydrogen atom bonded to the carbon atom in the group represented by R'may be substituted with a fluorine atom or an iodine atom. m represents an integer of 0 or more. The upper limit of m is not particularly limited, and it is often 2 or less, and more is 1 or less.

(Repeating unit represented by formula (E)) As an example of the specific realization of the above (e), a method of introducing the repeating unit represented by formula (E) into the resin (A) can be cited.

[Chemical formula 42]

In formula (E), Re each independently represents a hydrogen atom or an organic group. As an organic group, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, etc. which may also have a substituent are mentioned. "Cylic" is a cyclic group containing carbon atoms of the main chain. The number of atoms contained in the cyclic group is not particularly limited.

As specific examples of the repeating unit represented by the formula (E), the following repeating units can be given.

[Chemical formula 43]

[Chemical formula 44]

In the above formula, R each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, and a halogen atom , Ester group (-OCOR" or -COOR": R" is an alkyl or fluorinated alkyl group with 1 to 20 carbons) or a carboxyl group. In addition, the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group, and the alkenyl group may each have a substituent. In addition, the hydrogen atom bonded to the carbon atom in the group represented by R may be substituted with a fluorine atom or an iodine atom. R'each independently represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group and an alkenyl group, a hydroxyl group, an alkoxy group, an acyloxy group, a cyano group, a nitro group, an amino group, a halogen atom, and an ester group (-OCOR" or -COOR": R" is an alkyl group or fluorinated alkyl group having 1 to 20 carbons) or a carboxyl group. In addition, the alkyl group, the cycloalkyl group, the aryl group, the aralkyl group, and the alkenyl group may each have a substituent. In addition, the hydrogen atom bonded to the carbon atom in the group represented by R'may be substituted with a fluorine atom or an iodine atom. m represents an integer of 0 or more. The upper limit of m is not particularly limited, and it is often 2 or less, and more is 1 or less. In addition, in formula (E-2), formula (E-4), formula (E-6), and formula (E-8), two Rs may be bonded to each other to form a ring.

The content of the repeating unit represented by the formula (E) is preferably 5 mol% or more with respect to the total repeating units in the resin (A), and more preferably 10 mol% or more. Moreover, as the upper limit, 60 mol% or less is preferable, and 55 mol% or less is more preferable.

"Repeating unit having at least one group selected from lactone group, sultone group, carbonate group, hydroxyl group, cyano group and alkali-soluble group" The resin (A) may have a repeating unit having at least one group selected from a lactone group, a sultone group, a carbonate group, a hydroxyl group, and a cyano alkali-soluble group. The repeating unit having a lactone group, a sultone group or a carbonate group possessed by the resin (A) includes the repeating unit described in the above "Repeating unit having a lactone group, sultone group or carbonate group" unit. The preferred content is also as described in the above "Repeating Unit with Lactone Group, Sultone Group or Carbonate Group".

The resin (A) may have a repeating unit having a hydroxyl group or a cyano group. This improves the substrate adhesion and developer affinity. The repeating unit having a hydroxyl group or a cyano group is preferably a repeating unit having an alicyclic hydrocarbon structure substituted by a hydroxyl group or a cyano group. It is preferable that the repeating unit having a hydroxyl group or a cyano group does not have an acid-decomposable group. Examples of the repeating unit having a hydroxyl group or a cyano group include repeating units represented by the following general formulas (AIIa) to (AIId).

[Chemical formula 45]

In the general formulas (AIIa) to (AIId), R _1c represents a hydrogen atom, a methyl group, a trifluoromethyl group, or a hydroxymethyl group. R _2c to R _4c each independently represent a hydrogen atom, a hydroxyl group, or a cyano group. Among them, _{at least one of R 2c} to R _4c represents a hydroxyl group or a cyano group. Preferably, one or two of R _2c to R _4c are hydroxyl groups, and the remainder are hydrogen atoms. More preferably, two of R _2c to R _4c are hydroxyl groups, and the remainder are hydrogen atoms.

The content of the repeating unit having a hydroxyl group or a cyano group is preferably 5 mol% or more with respect to the total repeating units in the resin (A), and more preferably 10 mol% or more. Moreover, as the upper limit, 40 mol% or less is preferable, 35 mol% or less is more preferable, and 30 mol% or less is more preferable.

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

[Chemical formula 46]

The resin (A) may have a repeating unit having an alkali-soluble group. Examples of alkali-soluble groups include carboxyl, sulfonamide, sulfonamido, bissulfonamido, and aliphatic alcohols substituted by electron withdrawing groups at the α position (for example, hexafluoroiso Propanol group), carboxyl group is preferred. Resin (A) contains a repeating unit having an alkali-soluble group, so that the resolution when used for contact hole applications is increased. Examples of the repeating unit having an alkali-soluble group include repeating units based on acrylic acid and methacrylic acid, such as repeating units having an alkali-soluble group directly bonded to the main chain of the resin, or bonding to the main chain of the resin via a linking group. Repeating units with alkali-soluble groups. In addition, the linking group may have a monocyclic or polycyclic cyclic hydrocarbon structure. As the repeating unit having an alkali-soluble group, a repeating unit based on acrylic acid or methacrylic acid is preferred.

The content of the repeating unit having an alkali-soluble group is preferably 0 mol% or more with respect to the total repeating units in the resin (A), more preferably 3 mol% or more, and even more preferably 5 mol% or more. As the upper limit, 20 mol% or less is preferable, 15 mol% or less is more preferable, and 10 mol% or less is more preferable.

Although the specific example of the repeating unit which has an alkali-soluble group is shown below, this invention is not limited to this. In specific examples, Rx represents H, CH ₃ , CH ₂ OH or CF ₃ .

[Chemical formula 47]

As a repeating unit having at least one group selected from a lactone group, a hydroxyl group, a cyano group, and an alkali-soluble group, a repeating unit having at least two types selected from a lactone group, a hydroxyl group, a cyano group, and an alkali-soluble group Preferably, a repeating unit having a cyano group and a lactone group is more preferred, and a repeating unit having a structure in which a cyano group is substituted on the lactone structure represented by the general formula (LC1-4) is even more preferred.

"Repeating units that have an alicyclic hydrocarbon structure and do not show acid decomposability" The resin (A) may have an alicyclic hydrocarbon structure and a repeating unit that does not show acid decomposability. This can reduce the elution of low-molecular components from the resist film into the liquid immersion liquid during liquid immersion exposure. Examples of such repeating units include 1-adamantyl (meth)acrylate, diamond alkyl (meth)acrylate, tricyclodecyl (meth)acrylate, or cyclohexyl (meth)acrylate. Base) Repeating units of acrylate, etc.

"Repeating unit represented by general formula (III) without any of hydroxyl group and cyano group" The resin (A) may not have any of a hydroxyl group and a cyano group and may have a repeating unit represented by the general formula (III).

[Chemical formula 48]

In the general formula (III), R ₅ represents a hydrocarbon group having at least one cyclic structure and not having any of a hydroxyl group and a cyano group. Ra represents a hydrogen atom, an alkyl group, or a -CH ₂ -O-Ra ₂ group. In the formula, Ra ₂ represents a hydrogen atom, an alkyl group or an acyl group.

The cyclic structure of R ₅ includes a monocyclic hydrocarbon group and a polycyclic hydrocarbon group. Examples of the monocyclic hydrocarbon group include a cycloalkyl group having 3 to 12 carbon atoms (more preferably a cycloalkyl group having 3 to 7 carbon atoms) or a cycloalkenyl group having 3 to 12 carbon atoms.

Examples of the polycyclic hydrocarbon group include a ring assembly hydrocarbon group and a crosslinked cyclic hydrocarbon group. Examples of the crosslinked cyclic hydrocarbon ring include a bicyclic hydrocarbon ring, a tricyclic hydrocarbon ring, and a tetracyclic hydrocarbon ring. In addition, as a crosslinked cyclic hydrocarbon ring, a fused ring in which a plurality of 5- to 8-membered cycloalkane rings are fused is also included. As the cross-linked cyclic hydrocarbon group, norbornyl, adamantyl, bicyclooctyl or tricyclo[5,2,1,0 ^2,6 ]decyl is preferred, norbornyl or adamantyl is more preferred .

The alicyclic hydrocarbon group may have a substituent, and examples of the substituent include a halogen atom, an alkyl group, a hydroxyl group protected by a protective group, and an amine group protected by a protective group. As the halogen atom, a bromine atom, a chlorine atom or a fluorine atom is preferred. As the alkyl group, methyl, ethyl, butyl or tertiary butyl is preferred. The above-mentioned alkyl group may further have a substituent. Examples of the substituent include a halogen atom, an alkyl group, a hydroxyl group protected by a protective group, or an amino group protected by a protective group.

Examples of the protective group include an alkyl group, a cycloalkyl group, an aralkyl group, a substituted methyl group, a substituted ethyl group, an alkoxycarbonyl group, and an aralkoxycarbonyl group. As the alkyl group, an alkyl group having 1 to 4 carbon atoms is preferred. As the substituted methyl group, methoxymethyl, methoxythiomethyl, benzyloxymethyl, tert-butoxymethyl, or 2-methoxyethoxymethyl is preferred. As the substituted ethyl group, 1-ethoxyethyl or 1-methyl-1-methoxyethyl is preferred. As the acyl group, aliphatic acyl groups having 1 to 6 carbon atoms, such as formyl, acetyl, propionyl, butyryl, isobutyryl, pentanyl, and trimethylacetyl, are preferred. As the alkoxycarbonyl group, an alkoxycarbonyl group having 1 to 4 carbon atoms is preferred.

It does not have any of a hydroxyl group and a cyano group, and the content of the repeating unit represented by the general formula (III) is preferably 0-40 mol% relative to the total repeating units in the resin (A), 0-20 mol% % Is better. Specific examples of the repeating unit represented by the general formula (III) are given below, but the present invention is not limited to these. In the formula, Ra represents H, CH ₃ , CH ₂ OH or CF ₃ .

[Chemical formula 49]

"Other Repeating Units" Furthermore, the resin (A) may have repeating units other than the above repeating units. For example, the resin (A) may also have a repeating unit selected from the group consisting of a repeating unit having an oxythiophene ring group, a repeating unit having a azolinone ring group, a repeating unit having a diazolinone ring group, and a hydantoin ring A repeating unit in a group of basic repeating units. Examples of such repeating units are shown below.

[Chemical formula 50]

In addition to the above repeating structural units, the resin (A) can also have various repeating structural units for the purpose of adjusting dry etching resistance, standard developer compatibility, substrate adhesion, resist profile, resolution, heat resistance, and sensitivity.

As the resin (A), (especially, when the composition is used for ArF applications), all repeating units are preferably composed of (meth)acrylate-based repeating units. In this case, it is possible to use those whose repeating units are all methacrylate-based repeating units, those whose repeating units are all acrylate-based repeating units, and those whose repeating units are all based on methacrylate-based repeating units and acrylate-based repeating units. In either case, the acrylate-based repeating unit is preferably 50 mol% or less of the total repeating unit.

The resin (A) can be synthesized according to a conventional method (for example, radical polymerization). As a polystyrene conversion value by the GPC method, the weight average molecular weight of the resin (A) is preferably 1,000 to 200,000, more preferably 3,000 to 20,000, and more preferably 5,000 to 15,000. By setting the weight average molecular weight of the resin (A) to 1,000 to 200,000, it is possible to further suppress the deterioration of heat resistance and dry etching resistance. In addition, it is possible to further suppress deterioration of developability and deterioration of film forming properties due to increased viscosity. The degree of dispersion (molecular weight distribution) of the resin (A) is usually 1 to 5, preferably 1 to 3, more preferably 1.2 to 3.0, and even more preferably 1.2 to 2.0. The smaller the dispersion, the better the resolution and the shape of the resist, and the sidewalls of the resist pattern are smoother and the roughness is better.

In the resist composition, the content of the resin (A) relative to the total solid content of the composition is preferably 50 to 99.9% by mass, and more preferably 60 to 99.0% by mass. In addition, the solid content means a component other than the solvent in the composition, and as long as it is a component other than the solvent, it may be a liquid component or a solid component. Moreover, resin (A) may use 1 type, and may use multiple types together.

＜Compounds that generate acid by actinic rays or radiation (photoacid generator)＞ The chemically amplified resist composition preferably contains a compound that generates acid by actinic rays or radiation (hereinafter, also referred to as “photo acid generator (PAG: Photo Acid Generator)”). The photoacid generator may be in the form of a low-molecular compound, or may be incorporated in a part of the polymer. In addition, the form of a low-molecular compound and the form of a part of the polymer may be used in combination. In addition, when the photoacid generator is in the form of a low-molecular compound, the molecular weight of the photoacid generator is preferably 3000 or less, more preferably 2000 or less, and more preferably 1000 or less. When the photoacid generator is incorporated in a part of the polymer, it may be incorporated in a part of the resin (A) or may be incorporated in a resin different from the resin (A). In the present invention, it is preferable that the photoacid generator is a low-molecular compound. The photoacid generator is not particularly limited as long as it is a well-known one, but it is preferable that actinic rays or radiation are irradiated with electron beams or extreme ultraviolet rays to generate organic acids such as sulfonic acid, bis(alkylsulfonyl sulfonate) ) A compound of at least one of imidine and tris(alkylsulfonyl) methide is preferred. More preferably, compounds represented by the following general formulas (ZI), (ZII), and (ZIII) can be cited.

[Chemical formula 51]

In the above general formula (ZI), R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represent an organic group. As _{the carbon number of the organic group of R 201} , R ₂₀₂ and R ₂₀₃ , 1-30 is preferable, and 1-20 is more preferable. In addition, two of R ₂₀₁ to R ₂₀₃ may be bonded to form a ring structure, or an oxygen atom, a sulfur atom, an ester bond, an amide 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 butylene group and a pentenyl group). Z ^- represents a non-nucleophilic anion (an anion whose ability to cause a nucleophilic reaction is significantly lower).

Examples of non-nucleophilic anions include sulfonic acid anions (aliphatic sulfonic acid anions, aromatic sulfonic acid anions, camphorsulfonic acid anions, etc.), carboxylic acid anions (aliphatic carboxylic acid anions, aromatic carboxylic acid anions, etc.) And aralkyl carboxylic acid anion, etc.), sulfonylimide anion, bis(alkylsulfonyl) iminium anion and tri(alkylsulfonyl) methide anion, etc.

The aliphatic part in the aliphatic sulfonic acid anion and the aliphatic carboxylic acid anion may be an alkyl group or a cycloalkyl group, preferably a linear or branched alkyl group having 1 to 30 carbon atoms and a carbon number 3-30 cycloalkyl.

As the aromatic group in the aromatic sulfonic acid anion and the aromatic carboxylic acid anion, an aryl group having 6 to 14 carbon atoms is preferred. For example, a phenyl group, a tolyl group, a naphthyl group, etc. can be mentioned.

The above-mentioned alkyl group, cycloalkyl group, and aryl group may have a substituent. Specific examples include halogen atoms such as nitro group and fluorine atom, carboxyl group, hydroxyl group, amino group, cyano group, alkoxy group (preferably carbon number 1-15), cycloalkyl group (preferably carbon number 3 ~15), aryl (preferably carbon number 6-14), alkoxycarbonyl (preferably carbon number 2-7 is preferred), acyl group (preferably carbon number 2-12), alkoxy Alkylcarbonyloxy (preferably carbon number 2-7), alkylthio (preferably carbon number 1-15), alkylsulfonyl group (preferably carbon number 1-15), alkylimino group Sulfonyl (preferably carbon number 1-15), aryloxysulfonyl group (preferably carbon number 6-20), alkylaryloxysulfonyl group (preferably carbon number 7-20), Cycloalkylaryloxysulfonyl (preferably with 10 to 20 carbons), alkoxyalkoxy (preferably with 5 to 20 carbons) and cycloalkylalkoxyalkoxy (preferably with Carbon number 8-20) and so on. Regarding the aryl group and ring structure possessed by each group, examples of the substituent include an alkyl group (preferably having 1 to 15 carbon atoms).

As the aralkyl group in the aralkylcarboxylic acid anion, an aralkyl group having 7 to 12 carbon atoms is preferred. For example, a benzyl group, a phenethyl group, a naphthylmethyl group, a naphthylethyl group, a naphthylbutyl group, etc. can be mentioned.

As the sulfonylimine anion, for example, a saccharin anion can be cited.

Preferably, the alkyl group in the bis(alkylsulfonyl)imide anion or the tri(alkylsulfonyl)methide anion is an alkyl group having 1 to 5 carbon atoms. Examples of substituents of these alkyl groups include halogen atoms, alkyl groups substituted by halogen atoms, alkoxy groups, alkylthio groups, alkoxysulfonyl groups, aryloxysulfonyl groups, and cycloalkylaryloxy groups. For the sulfonyl group and the like, a fluorine atom or an alkyl group substituted with a fluorine atom is preferred. In addition, the alkyl groups in the bis(alkylsulfonyl)imide anion may be bonded to each other to form a ring structure. With this, the acid strength increases.

As another non-affinity anions, e.g., fluorinated phosphorus can include (e.g., PF ₆ ^-), boron trifluoride (e.g., BF ₄ ^-), antimony fluoride (e.g., SbF ₆ ^-) and the like.

As non-affinity anions, aliphatic sulfonic acid anions in which at least the α-position in sulfonic acid is substituted by fluorine atoms, aromatic sulfonic acid anions substituted by fluorine atoms or groups with fluorine atoms, and double alkyl groups substituted by fluorine atoms (Alkylsulfonyl)imide anion and tris(alkylsulfonyl)methide anion in which the alkyl group is substituted with a fluorine atom are preferred. As the non-affinity anion, perfluoroaliphatic sulfonic acid anion (preferably carbon 4-8) or benzenesulfonic acid anion with fluorine atom is more preferred, nonafluorobutane sulfonic acid anion, perfluorooctane sulfonic acid Anion, pentafluorobenzenesulfonic acid anion or 3,5-bis(trifluoromethyl)benzenesulfonic acid anion is more preferable.

From the standpoint of acid strength or sensitivity, the pKa of the generated acid is preferably -1 or less.

Moreover, as a non-affinity anion, the anion represented by the following general formula (AN1) can also be mentioned as a preferable aspect.

[Chemical formula 52]

In the formula, Xf each independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. R ¹ and R ² each independently represent a hydrogen atom, a fluorine atom, or an alkyl group, and when a plurality of R ¹ and R ^{2 are present, they} may be the same or different. L represents a divalent linking group, and when a plurality of them are present, L may be the same or different from each other. A represents a cyclic organic group. x represents an integer of 1-20, y represents an integer of 0-10, and z represents an integer of 0-10.

The general formula (AN1) is explained in further detail. As the carbon number of the alkyl group in the alkyl group substituted with a fluorine atom of Xf, 1-10 is preferable, and 1-4 are more preferable. Furthermore, the alkyl group substituted with a fluorine atom of Xf is preferably a perfluoroalkyl group. Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms. Specific examples of Xf include fluorine atom, CF ₃ , C ₂ F ₅ , C ₃ F ₇ , C ₄ F ₉ , CH ₂ CF ₃ , CH ₂ CH ₂ CF ₃ , CH ₂ C ₂ F ₅ , CH ₂ CH ₂ C ₂ F ₅ , CH ₂ C ₃ F ₇ , CH ₂ CH ₂ C ₃ F ₇ , CH ₂ C ₄ F ₉ and CH ₂ CH ₂ C ₄ F ₉ . Among them, a fluorine atom or CF ₃ is preferred. In particular, it is preferable that two Xf are fluorine atoms.

The alkyl group of R ¹ and R ² may have a substituent (preferably a fluorine atom), and the carbon number is preferably 1 to 4. Among them, ^{the alkyl group of R 1} and R ² is preferably a perfluoroalkyl group having 1 to 4 carbon atoms. Specific examples of the alkyl group having substituents for R ¹ and R ² _{include CF 3} , C ₂ F ₅ , C ₃ F ₇ , C ₄ F ₉ , C ₅ F ₁₁ , C ₆ F ₁₃ , and C ₇ F ₁₅ , C ₈ F ₁₇ , CH ₂ CF ₃ , CH ₂ CH ₂ CF ₃ , CH ₂ C ₂ F ₅ , CH ₂ CH ₂ C ₂ F ₅ , CH ₂ C ₃ F ₇ , CH ₂ CH ₂ C ₃ F _7. CH ₂ C ₄ F ₉ and CH ₂ CH ₂ C ₄ F ₉ . Among them, CF ₃ is preferred. As R ¹ and R ² , a fluorine atom or CF ₃ is preferable.

It is preferable that x is 1-10, and it is more preferable that it is 1-5. It is preferable that y is 0-4, and 0 is more preferable. It is preferable that z is 0-5, and it is more preferable that it is 0-3. The divalent linking group of L is not particularly limited, and examples include -COO-, -OCO-, -CO-, -O-, -S-, -SO-, -SO ₂ -, alkylene, Cycloalkylene, alkenylene, and linking groups to which a plurality of these are connected, and the like. Among them, a linking group having a total carbon number of 12 or less is preferred. Furthermore, -COO-, -OCO-, -CO- or -O- is preferable, and -COO- or -OCO- is more preferable.

In the above general formula (AN1), as a combination of partial structures other than A, SO ^3- -CF ₂ -CH ₂ -OCO-, SO ^3- -CF ₂ -CHF-CH ₂ -OCO-, SO ^3- -CF ₂ -COO-, SO ^3- -CF ₂ -CF ₂ -CH ₂ -and SO ^3- -CF ₂ -CH(CF ₃ )-OCO- are preferred.

The cyclic organic group of A is not particularly limited as long as it has a cyclic structure. Examples include alicyclic groups, aryl groups, and heterocyclic groups (not only those having aromatic properties, but also those not having aromatic Sex) and so on. As an alicyclic group, it can be monocyclic or polycyclic, monocyclic cycloalkyl, norbornyl, tricyclodecyl, tetracyclodecyl, tetracyclodecyl, such as cyclopentyl, cyclohexyl, and cyclooctyl. A polycyclic cycloalkyl group such as a dialkyl group or an adamantyl group is preferable. Among them, from the viewpoint of suppressing the diffusibility in the film during the heating process after exposure and improving the MEEF (mask error enhancement factor), norbornyl, tricyclodecyl, tetracyclodecyl, and tetracyclodecyl Alicyclic groups having a bulky structure with a carbon number of 7 or more, such as dodecyl or adamantyl, are preferred. Examples of the aryl group include a benzene ring, a naphthalene ring, a phenanthrene ring, and an anthracene ring. Examples of the heterocyclic group include those derived from a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a pyridine ring. Among them, those derived from furan ring, thiophene ring or pyridine ring are preferred.

Moreover, as a cyclic organic group, a lactone structure can also be mentioned, As a specific example, the lactone structure represented by the following general formula (LC1-1)-(LC1-17) is mentioned.

[Chemical formula 53]

The above-mentioned cyclic organic group may have a substituent. Examples of the above-mentioned substituent include an alkyl group (any one of linear, branched, and cyclic, preferably having 1 to 12 carbon atoms), Cycloalkyl (monocyclic, polycyclic, or spiro ring is acceptable, carbon number 3-20 is preferred), aryl group (carbon number 6-14 is preferred), hydroxyl, alkoxy, ester group , Amide group, urethane group, urea group, thioether group, sulfonamide group and sulfonate group, etc. In addition, the carbon constituting the cyclic organic group (the carbon that contributes to the formation of the ring) may be a carbonyl carbon. _{In addition, the aforementioned substituent corresponds to Rb 2} in the aforementioned (LC1-1) to (LC1-17). In addition, in the above (LC1-1) to (LC1-17), n2 represents an integer of 0-4. When n2 is 2 or more, the presence of a plurality of Rb ₂ may be the same or different from each other, and the presence of a plurality of Rb ₂ may be bonded to each other to form a ring.

In the general formula (ZI), _{examples of the organic group of R 201} , R ₂₀₂ and R ₂₀₃ include an aryl group, an alkyl group, a cycloalkyl group, and the like. It _{is preferable that at least one of R 201} , R ₂₀₂ and R ₂₀₃ is an aryl group, and it is more preferable that all three of R 201, R 202 and R 203 are aryl groups. As the aryl group, in addition to phenyl, naphthyl, etc., heteroaryl groups such as indole residues and pyrrole residues may also be used. _Examples of the alkyl group and cycloalkyl group of R ₂₀₁ to R 203 include a linear or branched alkyl group having 1 to 10 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. As the alkyl group, methyl, ethyl, n-propyl, isopropyl, or n-butyl are preferred. As the cycloalkyl group, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, etc. are preferred. These groups may further have substituents. Examples of substituents that may be further included include halogen atoms such as nitro and fluorine atoms, carboxyl groups, hydroxyl groups, amino groups, cyano groups, alkoxy groups (preferably with 1 to 15 carbon atoms), and cycloalkyl groups (preferably Are carbon 3-15), aryl (preferably carbon 6-14), alkoxycarbonyl (preferably carbon 2-7), acyl (preferably carbon 2-12) and alkane Oxycarbonyloxy (preferably carbon number 2-7) and the like, but not limited to them.

Next, the general formulas (ZII) and (ZIII) will be described. In general formulas (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 , phenyl and naphthyl are preferred, and phenyl is more preferred. The aryl group of R ₂₀₄ to R ₂₀₇ may also be an aryl group having a heterocyclic structure including an oxygen atom, a nitrogen atom, a sulfur atom, and the like. Examples of the skeleton of the aryl group having a heterocyclic structure include pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene. As _{the alkyl group and cycloalkyl group in R 204} to R ₂₀₇ , a linear or branched alkyl group having 1 to 10 carbon atoms (for example, methyl, ethyl, propyl, butyl, and pentyl) and carbon Cycloalkyl groups of 3-10 (cyclopentyl, cyclohexyl, norbornyl) are preferred.

The aryl group, alkyl group, and cycloalkyl group of R ₂₀₄ to R _{207 may have a substituent.} Examples of substituents that the aryl group, alkyl group and cycloalkyl group of R ₂₀₄ to R ₂₀₇ may have include an alkyl group (for example, carbon number 1 to 15), cycloalkyl group (for example, carbon number 3 to 15), Aryl group (for example, carbon number 6-15), alkoxy group (for example, carbon number 1-15), halogen atom, hydroxyl group, thiophenyl group, etc.

In the general formula (ZII), Z ^- represents a non-nucleophilic anion. ^{Specifically, it is the same as that described as Z-} in the general formula (ZI), and the preferred form is also the same.

Below, although the specific example of general formula (ZI)-(ZIII) is shown, it is not limited to this.

[Chemical formula 54]

In the present invention, the acid generated from the diffusion suppressing the exposure the non-exposed portion and to optimize the viewpoint of resolution of the photoacid generator is irradiated by an electron beam or extreme ultraviolet generated volume greater than 130Å ³ acid (More preferably a sulfonic acid) compound, a compound that produces an acid with a volume of 190 Å ³ or more (more preferably a sulfonic acid) is more preferable, a compound that produces an acid (more preferably a sulfonic acid) with a volume of 270 Å ³ or more For further preference, compounds that generate acids (more sulfonic acids) with a volume of 400 Å ^{3 or more are particularly preferred.} Wherein, sensitivity and coating solvent solubility from the viewpoint of the volume of 2000Å ³ or less is preferred, 1500Å ³ or less is further preferred. The value of the above-mentioned volume was obtained using "WinMOPAC" manufactured by FUJITSU LIMITED. First input the chemical structure of the acid in each case, and then use the structure as the initial structure. Determine the most stable three-dimensional configuration of each acid by using the molecular force field calculation of the MM3 method. Then, perform the most stable three-dimensional configuration Using the molecular orbital calculation of the PM3 method, it is possible to calculate the "accessible volume" of each acid. In addition, 1Å means 0.1 nm. In the present invention, a photoacid generator which generates an acid exemplified below by irradiation with actinic rays or radiation is preferred. In addition, mark the calculated value of the volume (unit Å ³ ) for some examples. In addition, the calculated value obtained here is the value of the volume of the acid bound to the proton at the anion part.

[Chemical formula 55]

[Chemical formula 56]

[Chemical formula 57]

As the photoacid generator, paragraphs [0368] to [0377] of Japanese Patent Application Publication No. 2014-041328 and paragraphs [0240] to [0262] of Japanese Patent Application Publication No. 2013-228681 (corresponding to U.S. Patent Application Publication Paragraph [0339] of Bulletin No. 2015/004533), and these contents are incorporated in this manual. In addition, as preferred specific examples, the following compounds can be cited, but they are not limited to these.

[Chemical formula 58]

[Chemical formula 59]

[Chemical formula 60]

[Chemical formula 61]

The photoacid generator can be used individually by 1 type or in combination of 2 or more types. The content of the photoacid generator in the resist composition is based on the total solid content of the composition, preferably 0.1-50% by mass, more preferably 5-50% by mass, and even more preferably 8-40% by mass . In particular, in order to achieve both high sensitivity and high resolution when performing electron beam or extreme ultraviolet exposure, it is preferable that the content of the photoacid generator is relatively high. From the above viewpoint, 10 to 40% by mass is preferable, and 10 to 35% by mass is more preferable.

＜Solvent＞ When the above-mentioned components are dissolved to prepare the resist composition, a solvent can be used. Examples of solvents that can be used include alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactate, alkyl alkoxypropionate, and carbon number. Organic solvents such as cyclic lactones having 4 to 10, monoketone compounds having 4 to 10 carbon atoms that may contain a ring, alkylene carbonate, alkyl alkoxy acetate, and alkyl pyruvate.

Examples of alkylene glycol monoalkyl ether carboxylates include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, and propylene glycol. Monomethyl ether propionate, propylene glycol monoethyl ether propionate, ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate. Examples of alkylene glycol monoalkyl ethers include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether.

Examples of alkyl lactate include methyl lactate, ethyl lactate, propyl lactate, and butyl lactate. Examples of the alkyl alkoxypropionate include ethyl 3-ethoxypropionate, 3-methoxypropionate, 3-ethoxymethylpropionate, and 3-methoxypropionate. Ethyl acid.

Examples of cyclic lactones having 4 to 10 carbon atoms include β-propiolactone, β-butyrolactone, γ-butyrolactone, α-methyl-γ-butyrolactone, and β-methyl-butyrolactone. γ-butyrolactone, γ-valerolactone, γ-caprolactone, γ-caprylic acid lactone and α-hydroxy-γ-butyrolactone.

Examples of monoketone compounds having 4 to 10 carbon atoms that may contain a ring include 2-butanone, 3-methyl butanone, tertiary butyl ethyl ketone, 2-pentanone, 3-pentanone, 3- Methyl-2-pentanone, 4-methyl-2-pentanone, 2-methyl-3-pentanone, 4,4-dimethyl-2-pentanone, 2,4-dimethyl-3 -Pentanone, 2,2,4,4-tetramethyl-3-pentanone, 2-hexanone, 3-hexanone, 5-methyl-3-hexanone, 2-heptanone, 3-heptanone , 4-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4-heptanone, 2-octanone, 3-octanone, 2 -Nonanone, 3-nonanone, 5-nonanone, 2-decanone, 3-decanone, 4-decanone, 5-hexen-2-one, 3-penten-2-one, cyclopentanone , 2-methylcyclopentanone, 3-methylcyclopentanone, 2,2-dimethylcyclopentanone, 2,4,4-trimethylcyclopentanone, cyclohexanone, 3-methylcyclopentanone Hexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 2,2-dimethylcyclohexanone, 2,6-dimethylcyclohexanone, 2,2,6-trimethyl Cyclohexanone, cycloheptanone, 2-methylcycloheptanone and 3-methylcycloheptanone.

Examples of alkylene carbonates include propylene carbonate, ethylene carbonate, ethylene carbonate, and ethylene carbonate. As the alkyl alkoxyacetate, for example, 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2-(2-ethoxyethoxy)ethyl acetate, 3-methoxy-3-methylbutyl acetate and 1-methoxy-2-propyl acetate. Examples of the alkyl pyruvate include methyl pyruvate, ethyl pyruvate, and propyl pyruvate. Among them, as the solvent, a solvent having a boiling point of 130°C or higher at normal temperature and pressure is preferred. Specifically, cyclopentanone, γ-butyrolactone, cyclohexanone, ethyl lactate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethyl 3-ethoxypropionate Ester, ethyl pyruvate, 2-ethoxy ethyl acetate, 2-(2-ethoxyethoxy) ethyl acetate and propylene carbonate.

The above-mentioned solvents may be used singly, or two or more kinds may be used.

In the present invention, as the organic solvent, a mixed solvent in which a solvent containing a hydroxyl group and a solvent not containing a hydroxyl group are mixed in the structure can also be used. As a solvent containing a hydroxyl group, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethyl lactate, etc. are mentioned, for example. Among them, propylene glycol monomethyl ether or ethyl lactate is preferred. As a solvent that does not contain a hydroxyl group, for example, propylene glycol monomethyl ether acetate, ethyl ethoxy propionate, 2-heptanone, γ-butyrolactone, cyclohexanone, butyl acetate, N- Methylpyrrolidone, N,N-dimethylacetamide and dimethylsulfene, etc. Among them, propylene glycol monomethyl ether acetate, ethyl ethoxy propionate, 2-heptanone, γ-butyrolactone, cyclohexanone or butyl acetate are preferred, propylene glycol monomethyl ether acetate, ethyl Ethoxy propionate or 2-heptanone is more preferred. The mass ratio of the content of the solvent containing the hydroxyl group to the content of the solvent not containing the hydroxyl group [the mass of the solvent containing the hydroxyl/the mass of the solvent not containing the hydroxyl] is preferably 1/99 to 99/1, 10/ 90 to 90/10 is more preferable, and 20/80 to 60/40 is still more preferable. In addition, from the viewpoint of coating uniformity, the mass of the solvent that does not contain a hydroxyl group in the mixed solvent is preferably 50% by mass or more.

The above-mentioned solvent is preferably a mixed solvent containing two or more kinds of propylene glycol monomethyl ether acetate, and a combination of γ-butyrolactone and butyl acetate is more preferred.

As the solvent, for example, the solvents described in paragraphs [0013] to [0029] of JP 2014-219664 A can also be used.

＜Acid diffusion control agent＞ In order to reduce the time-dependent performance change from exposure to heating, the resist composition preferably contains an acid diffusion control agent.

As an acid diffusion control agent, a basic compound can be mentioned, for example. As a basic compound, the compound which has a structure represented by following formula (A1)-(E1) is mentioned, for example.

[Chemical formula 62]

^{R 200} , R ²⁰¹ and R ²⁰² in the general formulas (A1) and (E1) may be the same or different from each other, and represent a hydrogen atom, an alkyl group (preferably carbon number 1-20), a cycloalkyl group (preferably It is a carbon number of 3-20) or an aryl group (preferably a carbon number of 6-20). In addition, R ²⁰¹ and R ²⁰² may also be bonded to each other to form a ring.

As the alkyl group having the above-mentioned 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 are preferred. R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different, and represent an alkyl group having 1 to 20 carbons. It is preferable that the alkyl group in the general formulas (A1) and (E1) is unsubstituted.

As the compound having the structure represented by the general formulas (A1) and (E1), in addition to guanidine, aminopyrrolidine, pyrazole, pyrazoline, piperazine, aminoporline, aminoalkylporline, In addition to piperidine, compounds having an imidazole structure, a diazabicyclic structure, an onium hydroxide structure, an onium carboxylate structure, a trialkylamine structure, an aniline structure, or a pyridine structure, and alkane having a hydroxyl group and/or ether linkage can be mentioned. Amine derivatives and aniline derivatives with hydroxyl and/or ether bonds, etc.

Examples of the compound having an imidazole structure include imidazole, 2,4,5-triphenylimidazole, benzimidazole, and the like. Examples of compounds having a diazabicyclic structure include 1,4-diazabicyclo[2,2,2]octane, 1,5-diazabicyclo[4,3,0]non-5- Ene and 1,8-diazabicyclo[5,4,0]undec-7-ene, etc. Examples of the compound having an onium hydroxide structure include triaryl sulfonium hydroxide, benzyl methyl sulfonium hydroxide, and sulfonium hydroxide having a 2-oxoalkyl group. Specifically, triphenyl sulfonium hydroxide, tris (tertiary butyl phenyl) sulfonium hydroxide, bis (tertiary butyl phenyl) sulfonium hydroxide, benzyl methyl thiophenium hydroxide and Hydroxide 2-oxopropylthiophenium and so on. As a compound having an onium carboxylate structure, the anion portion of a compound having an onium hydroxide structure becomes a carboxylate, for example, acetate, adamantane-1-carboxylate, and perfluoroalkylcarboxylate Wait. Examples of the compound having a trialkylamine structure include tri(n-butyl)amine, tri(n-octyl)amine, and the like. Examples of the aniline compound include 2,6-diisopropylaniline, N,N-dimethylaniline, N,N-dibutylaniline, N,N-dihexylaniline, and the like. Examples of alkylamine derivatives having a hydroxyl group and/or an ether bond include ethanolamine, diethanolamine, triethanolamine, tris(methoxyethoxyethyl)amine, and the like. Examples of aniline derivatives having a hydroxyl group and/or ether bond include N,N-bis(hydroxyethyl)aniline and the like.

As the basic compound, an amine compound having a phenoxy group and an ammonium salt compound having a phenoxy group can also be further cited.

As the amine compound, primary, secondary, and tertiary amine compounds can be used, and an amine compound in which at least one alkyl group is bonded to a nitrogen atom is preferred. The amine compound is more preferably a tertiary amine compound. As long as the amine compound has at least one alkyl group (preferably carbon number 1-20) bonded to the nitrogen atom, in addition to the alkyl group, it may also be a cycloalkyl group (preferably carbon number 3-20) or an aryl group ( Preferably, 6-12 carbon atoms are bonded to a nitrogen atom. In addition, the amine compound has an oxygen atom in the alkyl chain, and it is preferable to form an oxyalkylene group. The number of oxyalkylene groups in the molecule is 1 or more, preferably 3-9, and more preferably 4-6. Among them, as oxyethylene group, oxyethylene group (-CH ₂ CH ₂ O-) or oxyethylene group (-CH(CH ₃ )CH ₂ O- or -CH ₂ CH ₂ CH ₂ O-) is more Preferably, oxyethylene is more preferable.

The ammonium salt compound can be a primary, secondary, tertiary or quaternary ammonium salt compound, and an ammonium salt compound in which at least one alkyl group is bonded to a nitrogen atom is preferred. As long as the ammonium salt compound has at least one alkyl group (preferably carbon number 1-20) bonded to a nitrogen atom, in addition to the alkyl group, it may also be a cycloalkyl group (preferably carbon number 3-20) or an aryl group (Preferably carbon number 6-12) is bonded to a nitrogen atom. The ammonium salt compound has an oxygen atom in the alkyl chain, and it is preferable to form an oxyalkylene group. The number of oxyalkylene groups in the molecule is 1 or more, preferably 3-9, and more preferably 4-6. Among them, as oxyethylene group, oxyethylene group (-CH ₂ CH ₂ O-) or oxyethylene group (-CH(CH ₃ )CH ₂ O- or -CH ₂ CH ₂ CH ₂ O-) is more Preferably, oxyethylene is more preferable. Examples of the anion of the ammonium salt compound include a halogen atom, sulfonate, borate, and phosphate. Among them, halogen atoms or sulfonates are preferred. As the halogen atom, chloride, bromide, and iodide are preferred. As the sulfonate, an organic sulfonate having 1 to 20 carbon atoms is preferred. As the organic sulfonate, alkyl sulfonate and aryl sulfonate having 1 to 20 carbon atoms are preferred. The alkyl group of the alkyl sulfonate may have a substituent, and examples of the substituent include fluorine, chlorine, bromine, alkoxy, acyl, and aryl. Examples of alkyl sulfonates include methane sulfonate, ethane sulfonate, butane sulfonate, hexane sulfonate, octane sulfonate, benzyl sulfonate, and trifluoromethane sulfonate. Salt, pentafluoroethane sulfonate and nonafluorobutane sulfonate, etc. Examples of the aryl group of the arylsulfonate include a benzene ring, a naphthalene ring, and an anthracene ring. The benzene ring, naphthalene ring, and anthracene ring may have a substituent. As the substituent, a linear or branched alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms are preferred. Examples of linear or branched alkyl groups and cycloalkyl groups include, specifically, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tertiary butyl, and n-hexyl groups. Group and cyclohexyl, etc. Examples of other substituents include alkoxy groups having 1 to 6 carbon atoms, halogen atoms, cyano groups, nitro groups, acyl groups, and acyloxy groups.

The amine compound having a phenoxy group or the ammonium salt compound having a phenoxy group refers to those having a phenoxy group at the end of the alkyl group of the amine compound or the ammonium salt compound on the opposite side to the nitrogen atom. The phenoxy group may have a substituent. As the substituent of the phenoxy group, for example, an alkyl group, an alkoxy group, a halogen atom, a cyano group, a nitro group, a carboxyl group, a carboxylate group, a sulfonate group, an aryl group, an aralkyl group, and an oxo group may be mentioned. Group and aryloxy group. The substitution position of the substituent may be any of the 2 to 6 positions. The number of substituents may be any one in the range of 1-5.

It is preferable to have at least one oxyalkylene group between the phenoxy group and the nitrogen atom. The number of oxyalkylene groups in the molecule is 1 or more, preferably 3-9, and more preferably 4-6. Among them, as oxyethylene group, oxyethylene group (-CH ₂ CH ₂ O-) or oxyethylene group (-CH(CH ₃ )CH ₂ O- or -CH ₂ CH ₂ CH ₂ O-) is more Preferably, oxyethylene is more preferable.

Amine compounds with phenoxy groups can be obtained by heating primary or secondary amines with phenoxy groups and haloalkyl ethers to make these reactions, and then adding sodium hydroxide, potassium hydroxide and tetraalkylammonium After the aqueous solution of strong base is equalized, extraction is performed with organic solvents such as ethyl acetate and chloroform. Or it can be obtained by heating the primary or secondary ammonium and the haloalkyl ether with a phenoxy group at the end to make these reactions, and then adding a strong base such as sodium hydroxide, potassium hydroxide and tetraalkylammonium After the aqueous solution, extraction is performed with organic solvents such as ethyl acetate and chloroform.

(Compounds (PA) that produce compounds with proton-accepting functional groups that are decomposed by the irradiation of actinic rays or radiation to decrease, disappear, or change from proton-accepting to acidic properties) The composition of the present invention, as an acid diffusion control agent, may further include generating functional groups with proton-accepting properties, which are decomposed by irradiation with actinic rays or radiation, and the proton-accepting properties are decreased, disappeared, or changed from proton-accepting properties. Compounds of acidic compounds [hereinafter, also referred to as compounds (PA). ].

The proton-accepting functional group is a functional group with a group or electrons capable of electrostatically interacting with protons, for example, it means a functional group with a macrocyclic structure such as cyclic polyether, or it has no effect on π conjugation. The functional group of the nitrogen atom that does not share an electron pair. The nitrogen atom having an unshared electron pair that does not contribute to π conjugation is, for example, a nitrogen atom having a partial structure represented by the following general formula.

[Chemical formula 63]

Examples of preferred partial structures of the proton-accepting functional group include crown ethers, aza crown ethers, mono- to tertiary amines, pyridine, imidazole, and pyridine structures.

The compound (PA) produces a compound that is decomposed by irradiation with actinic rays or radiation to decrease or disappear proton accepting properties, or change from proton accepting properties to acidity. Here, the decrease, disappearance, or change of proton-accepting property from proton-accepting property to acidity is a change in proton-accepting property caused by the addition of protons to the proton-accepting functional group. When the compound of the body functional group (PA) and the proton form the proton adduct, the equilibrium constant in the chemical equilibrium decreases.

As specific examples of the compound (PA), for example, the following compounds can be given. Furthermore, as specific examples of the compound (PA), for example, paragraphs [0421] to [0428] of JP 2014-041328 and paragraphs [0108] to [0116] of JP 2014-134686 can be cited. Recorded, and these contents are incorporated in this manual.

[Chemical formula 64]

[Chemical formula 65]

[Chemical formula 66]

An acid diffusion control agent may be used individually by 1 type, and may use 2 or more types. The content of the acid diffusion control agent is preferably 0.001 to 10% by mass relative to the total solid content of the resist composition, and more preferably 0.005 to 5% by mass.

The use ratio of the photoacid generator and the acid diffusion control agent in the composition is preferably the photoacid generator/acid diffusion control agent (molar ratio)=2.5-300. From the viewpoint that the effect of the present invention is more excellent, the molar ratio is preferably 2.5 or more. From the viewpoint of suppressing the decrease in resolution due to the thickening of the resist pattern over time until the heat treatment after exposure, 300 or less is preferable. The photoacid generator/acid diffusion control agent (molar ratio) is more preferably 5.0 to 200, and more preferably 7.0 to 150.

As the acid diffusion control agent, for example, the compounds described in paragraphs [0140] to [0144] of JP 2013-011833 A (amine compounds, amide group-containing compounds, urea compounds, nitrogen-containing heterocyclic compounds, etc.) can be used .

＜Hydrophobic resin＞ The resist composition may contain a hydrophobic resin in addition to the above-mentioned resin (A). It is better that the hydrophobic resin is designed to be unevenly distributed on the surface of the resist film, but unlike surfactants, it is not necessary to have a hydrophilic group in the molecule, and it does not work for the uniform mixing of polar/non-polar substances. . As an effect of adding a hydrophobic resin, control of the static/dynamic contact angle of the surface of the resist film with respect to water and suppression of outgassing can be mentioned.

From the viewpoint of uneven distribution on the surface of the film, it is preferable that the hydrophobic resin has any one or more of _{fluorine atoms, silicon atoms, and the CH 3 partial structure contained in the side chain portion of the resin, and more preferably two or more} . Moreover, it is preferable that the said hydrophobic resin contains a C5 or more hydrocarbon group. These groups may exist in the main chain of the resin, or they may be substituted in the side chain.

When the hydrophobic resin contains fluorine atoms and/or silicon atoms, the above-mentioned fluorine atoms and/or silicon atoms in the hydrophobic resin may be contained in the main chain of the resin or may be contained in the side chain.

When the hydrophobic resin 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 having 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 Substituents other than fluorine atoms. The cycloalkyl group having a fluorine atom is a monocyclic or polycyclic cycloalkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and may have a substituent other than a fluorine atom. As the aryl group having a fluorine atom, at least one hydrogen atom of an aryl group such as a phenyl group and a naphthyl group is substituted with a fluorine atom, and it may have a substituent other than a fluorine atom. As an example of the repeating unit having a fluorine atom or a silicon atom, those exemplified in paragraph [0519] of US2012/0251948A1 can be cited.

In addition, as described above, it is preferable _{that the hydrophobic resin includes a CH 3 partial structure in the side chain portion.} Here, the hydrophobic side chain moiety in the resin having a partial structure of CH ₃ in _3-based partial structure comprising ethyl and propyl possessed of CH. On the other hand, the methyl group directly bonded to the main chain of the hydrophobic resin (for example, the α-methyl group having a repeating unit of methacrylic acid structure) is affected by the main chain and causes unevenness on the surface of the hydrophobic resin. It plays a small role and is therefore regarded as a part _{of the CH 3 structure included in the present invention.}

Regarding the hydrophobic resin, reference can be made to the description in paragraphs [0348] to [0415] of JP 2014-010245 A, and these contents are incorporated in this specification.

In addition, as the hydrophobic resin, resins described in Japanese Patent Application Publication No. 2011-248019, Japanese Patent Application Publication No. 2010-175859, and/or Japanese Patent Application Publication No. 2012-032544 can also be preferably used in addition to this.

＜Surface active agent＞ The resist composition may further include a surfactant. By including a surfactant, when using an exposure light source with a wavelength of 250 nm or less, especially 220 nm or less, a pattern with less adhesion and development defects can be formed with good sensitivity and resolution. As the surfactant, it is particularly preferable to use a fluorine-based and/or silicon-based surfactant. As the fluorine-based and/or silicon-based surfactants, for example, the surfactants described in paragraph [0276] of U.S. Patent Application Publication No. 2008/0248425 can be cited. In addition, EFTOP EF301 or EF303 (manufactured by Shin-Akita Kasei Co., Ltd.); Fluorad FC430, 431 or 4430 (manufactured by Sumitomo 3M Limited); MEGAFAC F171, F173, F176, F189, F113, F110, F177, F120 or R08 (manufactured by DIC Corporation); Surflon S-382, SC101, 102, 103, 104, 105 or 106 (manufactured by ASAHI GLASS CO., LTD.); TroySol S-366 (manufactured by Troy Chemical Industriesm, Inc.); GF-300 or GF-150 (manufactured by TOAGOSEI CO., LTD.), Surflon S-393 (manufactured by SEIMI CHEMICAL CO., LTD.); EFTOP EF121, EF122A, EF122B, RF122C, EF125M, EF135M, EF351, EF352, EF801 , EF802 or EF601 (manufactured by Gemco Co., Ltd); PF636, PF656, PF6320 or PF6520 (manufactured by OMNOVA Solutions Inc.); or FTX-204G, 208G, 218G, 230G, 204D, 208D, 212D, 218D or 222D (Neos Corporation). In addition, polysiloxane polymer KP-341 (manufactured by Shin-Etsu Chemical Co., Ltd.) can also be used as a silicon-based surfactant.

Furthermore, in addition to the well-known surfactants shown above, the surfactant can also be used by a short-chain polymerization (telomerization) method (also called a short-chain polymer (telomer) method) or an oligomerization method (also called a Oligomer method) to synthesize fluoroaliphatic compounds. Specifically, a polymer having a fluoroaliphatic group derived from the fluoroaliphatic compound can also be used as a surfactant. The fluoroaliphatic compound can be synthesized, for example, by the method described in JP 2002-090991 A. In addition, the fluorine-based and/or silicon-based surfactants described in paragraph [0280] of U.S. Patent Application Publication No. 2008/0248425 may also be used.

Surfactant may be used individually by 1 type, and may use 2 or more types.

When the resist composition contains a surfactant, its content is preferably 0-2% by mass relative to the total solid content of the composition, more preferably 0.0001-2% by mass, and still more preferably 0.0005-1% by mass.

＜Other additives＞ The chemically amplified resist composition may further include a dissolution inhibiting compound, dye, plasticizer, photosensitizer, light absorber, and/or a compound that promotes solubility in the developer (for example, a phenol compound with a molecular weight of 1000 or less, or Alicyclic or aliphatic compounds containing carboxyl groups).

The resist composition may further include a dissolution inhibiting compound. Here, the "dissolution inhibiting compound" is a compound having a molecular weight of 3000 or less that is decomposed by the action of an acid to reduce the solubility in an organic developer.

[Manufacturing method of treatment liquid] In order to set the content of metal components and organic substances having a boiling point of 300°C or higher within a desired range, it is preferable that the treatment liquid of the present invention be subjected to the following purification process.

＜Purification process＞ The purification process can be implemented at any time. As the purification process, for example, the following purification treatments I to IV can be mentioned. That is, the purification treatment I is a treatment for purifying the raw materials used in the production of the above-mentioned organic solvent before the organic solvent constituting the treatment liquid is produced. In addition, the purification treatment II is a treatment for purifying the organic solvent that constitutes the treatment liquid when and/or after it is produced. In addition, when the purification treatment III is to produce a treatment liquid, before mixing two or more organic solvents, each component is purified. In addition, when the purification treatment IV is to produce a treatment liquid, after mixing two or more kinds of organic solvents, the mixture is purified. As described above, it is preferable to perform purification in order to obtain the target treatment liquid. Regarding the purification, it may be mixed after purifying each organic solvent, or it may be purified after mixing each organic solvent. In particular, from the viewpoint that the blending ratio of the organic solvent can be made constant, the method of blending the purified organic solvent is preferable. The purification treatments I to IV may be carried out only once, respectively, or they may be carried out twice or more. In addition, as the organic solvent used, it is possible to purchase high-purity products (especially those containing less organic impurities, metal impurities, and water, etc.), and to further use them after purification treatment as described below.

Below, an example of the purification process is shown. In the following description, the purification object in the purification process is referred to as "purified liquid" for short. As the purification process, for example, the following treatments are sequentially performed: the first ion exchange treatment, the ion exchange treatment of the purified liquid; the dehydration treatment, the dehydration of the purified liquid after the first ion exchange treatment; and the distillation Treatment, the distillation of the purified liquid after the dehydration treatment; the second ion exchange treatment, the ion exchange treatment of the purified liquid after the distillation treatment; and the organic impurity removal treatment, the distillation of the purified liquid after the second ion exchange treatment Removal of organic impurities. In addition, the above purification process is described as an example below, but the purification method when preparing the treatment liquid of the present invention is not limited to this. For example, the following treatments may be sequentially performed: first, a dehydration treatment for dehydrating the purified liquid; a distillation treatment for distilling the purified liquid after the dehydration treatment; and a second ion exchange treatment for the purified liquid. 1 ion exchange treatment; and organic impurity removal treatment for removing organic impurities from the purified liquid after the second ion exchange treatment.

According to the first ion exchange treatment, ion components (for example, metal components, etc.) in the purified liquid can be removed. In the first ion exchange treatment, a first ion exchange mechanism such as an ion exchange resin is used. As the ion exchange resin, there can be one in which a cation exchange resin or an anion exchange resin is installed in a single bed, a cation exchange resin and an anion exchange resin are installed in multiple beds, and a cation exchange resin and an anion exchange resin are installed in a mixed bed. Any kind. In addition, as the ion exchange resin, in order to reduce the elution of water from the ion exchange resin, it is preferable to use a dry resin that does not contain water as much as possible. As such dry resins, commercially available products can be used, including 15JS-HG·DRY (product name, dry cation exchange resin, moisture content 2% or less) manufactured by Organo Corporation, and MSPS2-1·DRY (product name, mixed bed Resin, moisture content below 10%) etc.

According to the dehydration treatment, the water in the purified liquid can be removed. In addition, when the zeolite described later (especially, molecular sieve (product name) manufactured by UNION SHOWA K.K., etc.) is used in the dehydration treatment, olefins can also be removed. Examples of the dehydration mechanism used in the dehydration treatment include a dehydration membrane, a water adsorbent that is insoluble in the purified liquid, an aeration displacement device and heating using a dry inert gas, or a vacuum heating device. When using a dehydration membrane, perform membrane dehydration based on pervaporation (PV) or vapor permeation (VP). The dehydration membrane is, for example, a water-permeable membrane module. As the dehydration membrane, a polyimide-based film, a cellulose-based film, a polyvinyl alcohol-based film, or the like, which is composed of a polymer material or an inorganic material such as zeolite, can be used. The water adsorbent is used by adding to the purified liquid. Examples of the water adsorbent include zeolite, phosphorus pentoxide, silica gel, calcium chloride, sodium sulfate, magnesium sulfate, zinc chloride anhydride, oleum, soda lime, and the like.

The distillation process can remove impurities eluted from the dehydration membrane, metal components in the purified liquid that are not easily removed in the first ion exchange treatment, fine particles (including fine particles when the metal component is fine), and water in the purified liquid. The distillation mechanism is constituted by, for example, a single-stage distillation apparatus. Through the distillation process, the impurities are concentrated in the distillation apparatus, etc. However, in order to prevent a part of the concentrated impurities from flowing out, it is preferable to provide a mechanism for regularly or stably discharging a part of the concentrated impurity liquid to the outside on the distillation mechanism.

According to the second ion exchange treatment, the impurities accumulated in the distillation device can be removed when they flow out. In addition, it is possible to remove eluates from pipes such as stainless steel (SUS) used as liquid transport pipes. Examples of the second ion exchange mechanism include those filled with ion exchange resin in a tower-shaped container, and ion adsorption membranes. Among them, an ion adsorption membrane is preferred from the viewpoint of being capable of processing at a high flow rate. Examples of the ion adsorption membrane include NEOSEPTA (product name, manufactured by ASTOM Corporation).

Each of the above treatments is preferably carried out in a closed state and in an inert gas atmosphere where the possibility of mixing water in the purified liquid is low. Moreover, in order to suppress the incorporation of moisture as much as possible, each treatment is preferably performed in an inert gas atmosphere with a dew point temperature of -70°C or less. The reason is that in an inert gas atmosphere of -70°C or less, the moisture concentration in the gas phase is 2 mass ppm or less, so the possibility that moisture will be mixed into the (purified liquid) becomes low.

As the purification process, in addition to the above-mentioned treatment, there can be mentioned an adsorption purification treatment using a metal component of silicon carbide described in International Publication No. WO2012/043496.

According to the organic impurity removal treatment, it is possible to remove high-boiling organic impurities (including organic substances with a boiling point above 300°C) contained in the purified liquid after the distillation treatment, which are not easily removed during the distillation treatment. As the organic impurity removal mechanism, for example, it can be implemented by an organic impurity adsorption member provided with an organic impurity adsorption filter capable of adsorbing organic impurities. In addition, the organic impurity adsorbing member is generally configured by including the organic impurity adsorbing filter and the base material for fixing the impurity adsorbing filter. From the viewpoint of improving the adsorption performance of organic impurities, it is preferable that the organic impurity adsorption filter has an organic skeleton capable of interacting with organic impurities on the surface (in other words, the surface is modified by the organic skeleton capable of interacting with organic impurities) . In addition, the so-called surface having an organic skeleton capable of interacting with organic impurities, as an example, a form in which the surface of the substrate constituting the organic impurity adsorption filter described later is provided with an organic skeleton capable of interacting with the organic impurities can be mentioned. As an organic substance skeleton capable of interacting with organic impurities, for example, a chemical structure capable of reacting with organic impurities to capture the organic impurities in the organic impurity adsorption filter can be cited. More specifically, when dioctyl phthalate, diisononyl phthalate, dioctyl adipate, or dibutyl phthalate are contained as organic impurities, benzene ring skeleton. In addition, when the ethylene propylene diene rubber is contained as an organic impurity, an alkylene skeleton can be mentioned as an organic skeleton. Moreover, when an n-long-chain alkyl alcohol (structural isomer when a 1-long-chain alkyl alcohol is used as a solvent) is contained as an organic impurity, an alkyl group can be mentioned as an organic substance skeleton. As the base material (material) constituting the organic impurity adsorption filter, cellulose, diatomaceous earth, nylon, polyethylene, polypropylene, polystyrene, fluororesin, etc. carrying activated carbon can be cited. In addition, as an organic impurity removal filter, a filter in which activated carbon is adhered to a non-woven fabric described in JP 2002-273123 A and JP 2013-150979 A can also be used.

In addition, the above-mentioned organic impurity removal treatment is not limited to the aspect in which an organic impurity adsorption filter capable of adsorbing organic impurities is used as described above. For example, it may be a aspect in which organic impurities are physically captured. Most organic impurities with a high boiling point above 250°C are relatively coarse (for example, compounds with a carbon number of 8 or more), so they can also be physically captured by using a filter with a pore size of about 1 nm. For example, when dioctyl phthalate is included as an organic impurity, the structure of dioctyl phthalate is greater than 10 Å (=1 nm). Therefore, by using an organic impurity removal filter with a pore size of 1 nm, dioctyl phthalate cannot pass through the pores of the filter. That is, dioctyl phthalate is physically captured by the filter, and therefore is removed from the purified substance. In this way, not only chemical interactions can be applied to the removal of organic impurities, but also physical removal methods can be applied. Among them, in this case, a filter with a pore size of 3 nm or more is used as the “filtering member” described later, and a filter with a pore size of less than 3 nm is used as an “organic impurity removal filter”.

In addition, the purification process may further have, for example, the purification treatment V and the purification treatment VI described later. The purification treatment V and the purification treatment VI can be carried out at any time, for example, after carrying out the purification process IV, etc. can be mentioned. The purification treatment V is a filtration treatment using a metal ion adsorption member for the purpose of removing metal ions. In addition, the purification treatment VI is a filtration treatment for removing coarse particles. Hereinafter, the purification treatment V and the purification treatment VI will be described.

In the purification treatment VI, as an example of a metal ion removal mechanism, filtration using a metal ion adsorption member equipped with a metal ion adsorption filter can be cited. The metal ion adsorption member is a structure having at least one metal ion adsorption filter, and it can also be a structure in which a plurality of metal ion adsorption filters are overlapped according to the desired purification level. The metal ion adsorption member is generally configured by including the metal ion adsorption filter and the base material for fixing the metal ion adsorption filter. The metal ion adsorption filter has the function of adsorbing metal ions in the purified liquid. In addition, the metal ion adsorption filter is preferably a filter capable of ion exchange. Here, there are no particular restrictions on the metal ions to be adsorbed, but from the viewpoint of being likely to cause defects in the semiconductor element, Fe, Cr, Ni, and Pb are preferable. From the viewpoint of improving the adsorption performance of metal ions, the metal ion adsorption filter preferably has acid groups on the surface. As an acid group, a sulfo group, a carboxyl group, etc. are mentioned. Examples of the base material (material) constituting the metal ion adsorption filter include cellulose, diatomaceous earth, nylon, polyethylene, polypropylene, polystyrene, and fluororesin.

In the purification treatment VI, as an example of the filtering mechanism, there can be mentioned an aspect implemented using a filtering member provided with a filter having a particle diameter of 20 nm or less. The purified liquid can remove particulate impurities from the purified liquid by adding the above-mentioned filter. Here, the "particulate impurities" include dust, dust, organic solid matter, and inorganic solid matter particles contained as impurities in the raw materials used in the production of the purified liquid, as well as when the purified liquid is purified. Dust, dust, particles of organic solid materials and inorganic solid materials that are trapped by pollutants, but are not dissolved in the purified liquid and exist as particles also belong to this category. In addition, "particulate impurities" also include colloidal impurities containing metal atoms. The metal atom is not particularly limited, and is selected from the group including Na, K, Ca, Fe, Cu, Mg, Mn, Li, Al, Cr, Ni, Zn, and Pb (preferably Fe, Cr, Ni, and Pb) When the content of at least one metal atom in the group is particularly low (for example, when the content of the above-mentioned metal atoms in the purified liquid is 1000 mass ppt or less), impurities including these metal atoms are likely to colloidize. With the aforementioned metal ion adsorption member, it is difficult to remove colloidal impurities. Therefore, by using a filter with a particle size of 20nm or less (for example, a precision filtration membrane with a pore size of 20nm or less), colloidal impurities can be effectively removed. The particulate impurities have a size that can be removed by a filter with a removal diameter of 20 nm or less, and specifically they are particles with a diameter of 20 nm or more. In addition, in this specification, particulate impurities may be referred to as "coarse particles". Among them, the particle diameter of the filter is preferably 1-15 nm, and more preferably 1-12 nm. If the removal particle size is 15 nm or less, finer particulate impurities can be removed by this, and if the removal particle size is 1 nm or more, the filtration efficiency of the purified liquid can thereby be improved. Here, the particle size removed refers to the smallest size of particles that can be removed by the filter. For example, when the particle diameter of the filter is 20 nm, particles with a diameter of 20 nm or more can be removed. Examples of the material of the filter include 6-nylon, 6,6-nylon, polyethylene, polypropylene, polystyrene, fluororesin, and the like.

The filter member may further have a filter having a particle diameter of 50 nm or more (for example, a fine filter membrane for removing particles with a pore diameter of 50 nm or more). In addition to colloidal impurities, especially colloidal impurities containing metal atoms such as iron or aluminum, there are also fine particles in the purified liquid. Filter membrane) Before filtering, use a filter with a particle size of 50nm or more (for example, a precision filter membrane for removing particles with a pore size of 50nm or more) to filter the purified liquid, thereby removing the filter with a particle size of 20nm or less (For example, a precision filtration membrane with a pore size of 20 nm or less) has improved filtration efficiency, and the removal performance of coarse particles has been further improved.

The purified liquid obtained through each of these treatments can be used in the preparation of the treatment liquid of the present invention or directly used as the treatment liquid of the present invention. In addition, as an example of the purification process described above, a case where all the processes are performed is shown, but it is not limited to this, and each of the processes described above may be performed individually, or a plurality of the processes described above may be combined. In addition, each of the above-mentioned processes may be performed once, or may be performed multiple times.

In addition to the above purification process, as a method of setting the contents of organic substances, metal components, and water contained in the treatment liquid with a boiling point of 300°C or higher within the desired range, there can also be mentioned the use of organic solvents that make up the treatment liquid. A method in which the raw material or the treatment liquid itself is contained in a container where impurities are less eluted. In addition, a method such as lining the inner wall of the pipe with a fluorine-based resin in order to prevent the metal component from eluting from the "pipe" or the like when the processing liquid is produced can also be cited.

〔Container (Container)﹞ The processing liquid of the present invention can be filled in any container, stored, transported, and used as long as corrosivity and the like are not a problem. As the container, it is preferable that the container for semiconductors has high cleanliness in the container and less elution of impurities. Specific examples of usable containers include "clean bottle" series manufactured by AICELLO CORPORATION and "pure bottle" manufactured by KODAMA PLASTICS Co., Ltd., but are not limited to these. The inner wall of the container (the wetted part in contact with the solution in the container) is preferably formed of a non-metallic material. As non-metallic materials, selected from polyethylene resin, polypropylene resin, polyethylene-polypropylene resin, tetrafluoroethylene resin (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene resin Ethylene-hexafluoropropylene copolymer resin (FEP), ethylene-tetrafluoroethylene copolymer resin (ETFE), ethylene-chlorotrifluoroethylene copolymer resin (ECTFE), polyvinylidene fluoride resin (PVDF), chlorotrifluoroethylene copolymer resin At least one of the group of (PCTFE) and polyvinyl fluoride resin (PVF) is more preferable. In particular, when a container with an inner wall of fluorine resin is used in the above, compared with the case of a container with an inner wall of polyethylene resin, polypropylene resin or polyethylene-polypropylene resin, the elution of ethylene or propylene oligomers can be suppressed. And other undesirable situations. As a specific example of such a container whose inner wall is a fluorine-based resin, for example, a FluoroPurePFA composite cylinder manufactured by Entegris Inc. can be cited. In addition, it is possible to use pages 4 of Japanese Special Publication No. Hei 3-502677, Page 3 of International Publication No. 2004/016526 Pamphlet, etc., and Pages 9 and 16 of International Publication No. 99/46309 Pamphlet, etc. The container described in. In addition, when the inner wall is designed as a non-metallic material, it is preferable that the elution of organic components in the non-metallic material in the treatment liquid is suppressed.

In addition, as the inner wall of the container, in addition to the aforementioned non-metallic materials, quartz or metal materials (more preferably electrolytically polished metal materials. In other words, it is possible to use electrolytically polished metal materials as much as possible). The aforementioned metal material (especially, the metal material used in the production of the electrolytically ground metal material) preferably contains more than 25% by mass of chromium relative to the total mass of the metal material. For example, stainless steel can be mentioned. The content of chromium in the metal material is more preferably 30% by mass or more with respect to the total mass of the metal material. In addition, there is no particular limitation on the upper limit, but it is usually preferably 90% by mass or less.

As stainless steel, there is no restriction|limiting in particular, A well-known stainless steel can be used. Among them, an alloy containing 8% by mass or more of nickel is preferable, and an austenitic stainless steel containing 8% by mass or more of nickel is more preferable. As austenitic stainless steels, for example, SUS (stainless steel, Steel Use Stainless) 304 (Ni content 8 mass%, Cr content 18 mass%), SUS304L (Ni content 9 mass%, Cr content 18% by mass), SUS316 (10% by mass Ni content, 16% by mass Cr content), SUS316L (12% by mass Ni content, 16% by mass Cr content), etc.

There is no particular limitation on the method of electrolytic polishing a metal material, and a known method can be adopted. For example, the methods described in paragraphs [0011] to [0014] of Japanese Patent Application Publication No. 2015-227501 and paragraphs [0036] to [0042] of Japanese Patent Application Publication No. 2008-264929 can be used.

It is presumed that the content of chromium in the passivation layer on the surface of the metal material by electrolytic polishing becomes more than the content of chromium in the parent phase. Therefore, it is presumed that the metal component does not easily flow out into the solution from the inner wall covered with the electrolytically polished metal material, so a solution with reduced metal components (metal impurities) can be obtained. In addition, it is preferable that the metal material is polished. The polishing method is not particularly limited, and a known method can be used. The size of the abrasive grains used in the fine polishing is not particularly limited. From the viewpoint that the surface irregularities of the metal material are more likely to become smaller, #400 or less is preferable. In addition, polishing is preferably performed before electrolytic polishing. In addition, the metal material may be processed by combining multiple stages of polishing, pickling, and magnetic fluid polishing performed by changing the size of the abrasive grains and the like.

In the present invention, the one having the container and the processing liquid contained in the container is also referred to as a solution container.

It is preferable that the inside of these containers is cleaned before being filled with the treatment liquid. When the liquid used in washing is the treatment liquid itself of the present invention or an organic solvent contained in the treatment liquid of the present invention, the effects of the present invention can be remarkably obtained. The treatment liquid of the present invention can also be transported and stored in containers such as gallon bottles or QT bottles after manufacture. Gallon bottles can be those using glass or other materials.

It is also possible to replace the inside of the container with an inert gas (nitrogen, argon, etc.) with a purity of 99.99995% by volume or more for the purpose of preventing changes in the composition of the processing liquid in storage. In particular, a gas with a lower water content is preferable. In addition, normal temperature may be used during transportation and storage, but the temperature may be controlled in the range of -20°C to 20°C in order to prevent deterioration.

〔Clean room〕 It is preferable that all operations, processing analysis, and measurement including the manufacturing of the processing liquid of the present invention, the unsealing and/or washing of the storage container, and the filling of the processing liquid, are performed in a clean room. It is better that the clean room meets the ISO14644-1 clean room standard. Meeting ISO (International Organization for Standardization) level 1, ISO level 2, ISO level 3 and ISO level 4 is better, meeting ISO level 1 or ISO level 2 is better, meeting ISO level 1 is even better . Operations including the manufacture of the treatment liquid, the unsealing and/or washing of the storage container, and the filling of the treatment liquid in the embodiments described later, treatment analysis, and measurement are performed in a class 2 clean room.

[Static elimination process] In the preparation and purification of the treatment liquid or the organic solvent contained in the treatment liquid of the present invention, it is also possible to further have a neutralization process. The neutralization process is a process of neutralizing at least one selected from the group consisting of raw materials, reactants, and refined products (hereinafter referred to as "purified products, etc."), thereby reducing the electrostatic potential of the refined products. There is no particular limitation on the method of neutralization, and a known neutralization method can be used. As a method of removing electricity, for example, a method of contacting the above-mentioned purified liquid or the like with a conductive material can be cited. The time for the above-mentioned purified liquid or the like to contact the conductive material is preferably 0.001 to 60 seconds, more preferably 0.001 to 1 second, and still more preferably 0.01 to 0.1 second. Examples of conductive materials include stainless steel, gold, platinum, diamond, and glassy carbon. As a method of bringing the purified liquid or the like into contact with the conductive material, for example, a method of arranging a grounded screen made of a conductive material in the pipeline and passing the purified liquid or the like therein.

The aforementioned neutralization process can also be implemented at any time from the supply of raw materials to the filling of the purified product, for example, at least selected from the group consisting of a raw material supply process, a reaction process, a liquid conditioning process, a purification process, a filtration process, and a filling process. It is preferable to set before one process, and it is more preferable to perform a static elimination process before inputting the purified substance into the container used in the above-mentioned processes. Thereby, it is possible to suppress the mixing of impurities from the container and the like into the purified product and the like. [Example]

Hereinafter, the present invention will be described with examples, but the present invention is not limited to these.

〔Sensitizing radiation or radiation sensitive composition (resist composition)〕 The sensitizing radiation or radiation-sensitive composition (resist composition) was prepared using the materials shown below.

＜Resin (A)＞ (Synthesis example 1): Synthesis of resin (A-1) Cyclohexanone (600 g) was placed in a 2L flask, and the above cyclohexanone was substituted with nitrogen at a flow rate of 100 mL/min for 1 hour. Then, polymerization initiator V-601 (manufactured by FUJIFILM Wako Pure Chemical Corporation) (4.60 g (0.02 mol)) was added to the flask, and the internal temperature of the contents of the flask was heated to 80°C. Next, 4-acetoxystyrene (48.66g (0.3mol)), 1-ethylcyclopentyl methacrylate (109.4g (0.6mol)), monomer 1 (22.2g (0.1mol)) And polymerization initiator V-601 (manufactured by FUJIFILM Wako Pure Chemical Corporation) (4.60 g (0.02 mol)) was dissolved in cyclohexanone (200 g) to prepare a monomer solution. The above-mentioned monomer solution was added dropwise to the above-mentioned flask whose internal temperature was heated to 80°C over 6 hours in the above-mentioned manner. After completion of the dropping, the reaction was further carried out at an internal temperature of 80°C for 2 hours.

[Chemical formula 67]

After the reaction solution (the contents of the above flask) was cooled to room temperature, it was added dropwise to hexane (3 L) to obtain a mixed solution that precipitated the polymer. The above mixed liquid was filtered to obtain a solid (filtered product). The obtained solid (filtered product) was dissolved in acetone (500 ml), added dropwise to hexane (3L) again, and the solid (filtered product) was again obtained in the same manner as above. The obtained solid was dried under reduced pressure to obtain 4-acetoxystyrene/1-ethylcyclopentyl methacrylate/monomer 1 copolymer (A-1a) (160 g).

In the reaction vessel, add the copolymer (A-1a) (10g), methanol (40ml), 1-methoxy-2-propanol (200ml) and concentrated hydrochloric acid (1.5ml) obtained above into the empty flask The reaction solution (the contents of the above flask) was heated to 80°C and stirred for 5 hours. After the reaction solution was naturally cooled to room temperature, it was added dropwise to distilled water (3 L) to obtain a mixed solution. The above mixed liquid was filtered to obtain a solid (filtered product). The obtained solid (filtered product) was dissolved in acetone (200ml) and added dropwise to distilled water (3L) again, and the solid (filtered product) was again obtained in the same manner as above. The obtained solid was dried under reduced pressure to obtain resin (A-1) (8.5 g). The weight average molecular weight of the resin (A-1) was 10,800, and the molecular weight dispersion (Mw/Mn) was 1.55.

(Synthesis examples 2 to 5): Synthesis of resins (A-2) to (A-5), except that the monomers used were changed, and resins (A-2) to were further synthesized in the same manner as in Synthesis Example 1 above. (A-5). The composition ratio (molar ratio) of each repeating unit in the resin was calculated by ^{1 H-NMR (Nuclear Magnetic Resonance) measurement.}

The resins used in the resist composition are shown in the following table. In the table, the "composition ratio (molar ratio)" column shows the content (composition ratio (molar ratio)) of each repeating unit constituting each resin. The content of each repeating unit shown in the "Structure" column corresponds to the value shown in the "Composition ratio (mole ratio)" column in order from the left.

[Table 1]

＜Photoacid generator＞ As the acid generator, the following components were used.

[Chemical formula 68]

＜Basic compound (acid diffusion control agent)＞ As the basic compound, the following components were used.

[Chemical formula 69]

＜Solvent＞ As the solvent, the following components were used. C-1: Propylene glycol monomethyl ether acetate C-2: Propylene glycol C-3: Ethyl lactate C-4: Cyclohexanone

＜Other additives＞ As other additives, the following components were used. Additive 1: 2-hydroxy-3-naphthoic acid Additive 2: Surfactant PF6320 (manufactured by OMNOVA Solutions Inc.)

＜Preparation of resist composition＞ Each component shown in the following Table 2 was dissolved in the solvent shown in the same table with the compounding shown in the same table. The obtained mixed liquid was filtered using a polyethylene filter having a pore size of 0.03 μm to obtain resist compositions 1-7.

[Table 2] Resin (A) Photoacid generator Basic compound Solvent (C) Other additives Resist composition 1 A-1 B-3 E-3 C-1 C-3 0.78g 0.19g 0.02g 40g 10g Resistor composition 2 A-2 B-1 E-1 C-1 C-4 0.77g 0.20g 0.03g 30g 20g Resistor composition 3 A-3 B-2 E-1 C-1 C-3 0.79g 0.18g 0.03g 40g 10g Resistor composition 4 A-4 B-2 E-2 C-1 C-2 0.81g 0.18g 0.008g 40g 10g Resistor composition 5 A-5 B-3 E-1 C-1 C-4 Additive 2 0.78g 0.19g 0.02g 20g 30g 0.01g Resistor composition 6 A-1 B-1 E-1 C-1 C-4 Additive 1 0.77g 0.20g 0.02g 30g 20g 0.03g Resistor composition 7 A-1 B-2 E-1 C-1 C-3 0.77g 0.20g 0.03g 67.5g 7.5g

[test] [Evaluation of simple analytical performance: EB exposure evaluation: Examples 1 to 11 and Comparative Examples 1 to 6] Using resist compositions 1 to 6 described in Table 2, resist patterns were formed by the following operations. Tables 3 and 4 show the details of the resist pattern formation conditions. Both EB exposure and EUV exposure are exposed to ionization of the resist film to generate secondary electrons, and the generated secondary electrons decompose the photoacid generator to generate acid. Therefore, as a simple exposure evaluation, even if EB exposure is used as evaluation instead of EUV exposure, the same results as EUV exposure can be reproduced.

＜Creation of patterns＞ (Coating of resist composition and baking after coating) The composition for forming an organic film (product name: AL412, manufactured by Brewer Science, Inc.) was applied on a 6-inch silicon wafer, and baked at 205°C for 60 seconds to form an organic film with a thickness of 20 nm . The resist composition described in Table 2 was coated thereon, and baked under the conditions described in Table 4 below (post-coating baking) to form a resist film with a film thickness of 60 nm.

(exposure) Using an electron beam irradiation device (G100 manufactured by ELIONIX INC.; acceleration voltage 100 keV, beam current 100 pA), the line and space pattern (length direction 0.2 mm, drawing number 45) with a half-pitch of 22 nm (length direction 0.2 mm, number of drawing lines 45) was adjusted to the values listed in Table 3. The exposure amount exposes the resist film in the wafer on which the resist film is formed in the above-mentioned manner (wafer with resist film). Specifically, the exposure was performed with the exposure amount corresponding to each Shot number in Table 3 shown below. Expose the resist film with each exposure amount (Shot), and provide the resist film exposed with each exposure amount to the subsequent manufacturing process. In addition, the exposures in Table 3 are set in the order of Shot numbers to be logically equal in intervals. Even when the sensitivity of the resist film used in the evaluation is different, the analysis performance can be compared by comparing the number of shots (the number of exposures that can be analyzed without problems) that can be finally analyzed without problems.

[table 3] Shot number Exposure (mJ/cm ² ) 1 250 2 222 3 198 4 177 5 157 6 140 7 125 8 112 9 99 10 89 11 79 12 70 13 63 14 56 15 50

(Bake after exposure) After exposure, the wafer was taken out of the electron beam irradiation device, and immediately heated on a hot plate under the conditions described in Table 4 (post-exposure baking).

(Development process) Using a shower-type developing device (ADE3000S manufactured by ACTES Co., Ltd.), while rotating the wafer at 50 rpm, the developer solution (23°C) described in Table 4 was sprayed on the wafer at a flow rate of 200 mL/min. 10 Seconds to develop.

(Flushing process) Then, while rotating the wafer at 50 rpm, the rinsing liquid (23° C.) described in Table 4 was sprayed on the wafer at a flow rate of 200 mL/min for 5 seconds to perform a rinsing process. Among them, in Comparative Example 1, rinsing treatment was not performed. Finally, the wafer was rotated at a high speed of 2000 rpm for 60 seconds to dry the wafer.

Table 4 is shown below, in which the pattern formation conditions in each Example or Comparative Example are described. In Table 4, the "resist composition" column shows the number of the resist composition used in the formation of the resist film. In addition, the combination of the developer and the rinse liquid described in Table 4 will be shown in Table 5 in the following paragraph.

[Table 4] Resistor composition exposure Bake after coating Baking after exposure Developer Rinsing fluid Example 1 1 EB 120℃×60 seconds 110℃×60 seconds S-13 S-1 Example 2 2 EB 120℃×60 seconds 100℃×60 seconds S-13 S-2 Example 3 3 EB 120℃×60 seconds 110℃×60 seconds S-13 S-3 Example 4 4 EB 120℃×60 seconds 110℃×60 seconds S-13 S-4 Example 5 5 EB 120℃×60 seconds 110℃×60 seconds S-13 S-6 Example 6 6 EB 120℃×60 seconds 110℃×60 seconds S-13 S-7 Example 7 1 EB 120℃×60 seconds 110℃×60 seconds S-13 S-4 Example 8 1 EB 120℃×60 seconds 110℃×60 seconds S-13 S-5 Example 9 1 EB 120℃×60 seconds 110℃×60 seconds S-13 S-8 Example 10 1 EB 120℃×60 seconds 110℃×60 seconds S-13 S-9 Example 11 3 EB 120℃×60 seconds 110℃×60 seconds S-13 S-10 Comparative example 1 1 EB 120℃×60 seconds 110℃×60 seconds S-13 - Comparative example 2 3 EB 120℃×60 seconds 110℃×60 seconds S-13 S-11 Comparative example 3 1 EB 120℃×60 seconds 110℃×60 seconds S-13 S-12 Comparative example 4 3 EB 120℃×60 seconds 110℃×60 seconds S-13 S-13 Comparative example 5 3 EB 120℃×60 seconds 110℃×60 seconds S-13 S-14 Comparative example 6 1 EB 120℃×60 seconds 110℃×60 seconds S-13 S-15 Comparative example 7 3 EB 120℃×60 seconds 110℃×60 seconds S-13 S-16

Table 5 shows the blending of the treatment liquids (developer or rinse liquid) described in Table 4. In Table 5, the column "bp1-bp2" shows the value (°C) obtained by subtracting the boiling point (bp2) of the second organic solvent from the boiling point (bp1) of the first organic solvent.

[table 5] Coordination of treatment liquid bp1-bp2 First organic solvent Second organic solvent Other organic solvents (quality%) (quality%) (quality%) (℃) S-1 Diisobutyl ketone Isoamyl formate - 44.0 (10% by mass) (90% by mass) S-2 Dibutyl Carbonate Isoamyl formate - 83.0 (10% by mass) (90% by mass) S-3 Hexyl propionate Diisobutyl ketone - 61.0 (50% by mass) (50% by mass) S-4 Isopropyl caproate Isopropyl propionate - 60.0 (30% by mass) (70% by mass) S-5 Mesitylene Isopropyl formate - 40.0 (10% by mass) (90% by mass) S-6 Diisobutyl ketone Dipropyl carbonate - 1.0 (30% by mass) (70% by mass) S-7 Diisobutyl ketone Diethyl carbonate - 42.0 (50% by mass) (50% by mass) S-8 Mesitylene Ethyl isobutyrate - 54.0 (50% by mass) (50% by mass) S-9 Butyl caproate Isopropyl formate - 84.0 (50% by mass) (50% by mass) S-10 Butyl caproate Diethyl carbonate - 82.0 (50% by mass) (50% by mass) S-11 Diisobutyl ketone - - - (100% by mass) S-12 - Isoamyl formate - - (100% by mass) S-13 - - Butyl acetate - (80% by mass) S-14 - - 2-heptanone - (100% by mass) S-15 - - Decane - (100% by mass) S-16 Diisobutyl ketone - Butyl acetate 42.0 (20% by mass) (80% by mass)

Tables 6 to 8 show the characteristics of the organic solvents used in the treatment liquids (developer or rinse liquid) described in Table 5. Table 6 shows the characteristics of the first organic solvent, Table 7 shows the characteristics of the second organic solvent, and Table 8 shows the characteristics of other organic solvents. In Tables 6 to 8, the "structure" column shows whether the first or second organic solvent has a linear or branched alkyl group. The description of "branched chain" means that the first or second organic solvent has a branched alkyl group. The description of "linear" means that the first or second organic solvent has a linear alkyl group and does not have a branched alkyl group.

[Table 6] Solvent name Straight chain/branched chain Molecular formula Boiling point (℃) Diisobutyl ketone Branched C ₉ H ₁₈ O 168 Dibutyl Carbonate Straight C ₉ H ₁₈ O ₃ 207 Hexyl propionate Straight C ₉ H ₁₈ O ₂ 186 Isopropyl caproate Branched C ₉ H ₁₈ O ₂ 168 Butyl caproate Straight C ₁₀ H ₂₀ O ₂ 208 Mesitylene Branched C ₉ H ₁₂ 164

[Table 7] Solvent name structure Molecular formula Boiling point (℃) Diisopropyl ketone Branched C ₇ H ₁₄ O 125 Isoamyl formate Branched C ₆ H ₁₂ O ₂ 124 Isopropyl propionate Branched C ₆ H ₁₂ O ₂ 108 Diethyl carbonate Straight C ₅ H ₁₀ O ₃ 126

[Table 8] Solvent name structure Molecular formula Boiling point (℃) Butyl acetate Straight C ₆ H ₁₂ O ₂ 126 2-heptanone Straight C ₇ H ₁₄ O 151 Decane Straight C ₁₀ H ₂₂ 174

＜Evaluation＞ With regard to the following items, the obtained patterns were evaluated. Table 9 shows the details of the results.

(Sensitivity) The obtained pattern was observed using a scanning electron microscope (S-9260 manufactured by Hitachi, Ltd.). In a line width of 22 nm, the irradiated energy for separation and analysis with a line to space ratio of 1:1 is used as the sensitivity of the resist film (μC/cm ² ).

(Analysis frame number (analysis)) A scanning electron microscope (S-9260 manufactured by Hitachi, Ltd.) was used to observe the analysis of the 22nm line and space pattern at each exposure amount. By counting the number of shots analyzed with each exposure amount without problems, the resolution was evaluated. Fig. 1 shows micrographs of the patterns formed by exposure with Shot numbers 3 to 10 in Example 1 and Comparative Example 1. In Comparative Example 1, only the case where exposure was performed with the exposure amount of Shot No. 4 was determined to be analyzed without problems. That is, in Comparative Example 1, the number of shots (analysis frames) that can be analyzed without problems is 1. Correspondingly, in Example 1, when the exposure is performed with the exposure amount of Shot No. 4 to 8, it is determined that the analysis is not problematic. That is, in Comparative Example 1, the number of shots (analysis frames) that can be analyzed without problems is 5. Based on the same determination criteria, the number of analysis frames was also obtained for other examples and comparative examples.

(Residue (residue inhibition)) A scanning electron microscope (S-9260 manufactured by Hitachi, Ltd.) was used to observe the unexposed part of the wafer, and it was confirmed whether there was any residue.

(Shape (Thinning suppression property)) A scanning electron microscope (S-4800 manufactured by Hitachi, Ltd.) was used to observe the shape of a pattern with a line width of 22 nm at an irradiation level showing the above sensitivity, and the shape of the obtained pattern was evaluated according to the following index. The closer the pattern shape is to a rectangle, the more it can be judged that thinning can be suppressed, the more significant the deterioration of the pattern shape, the more thinning it can be judged to be. A: Rectangle B: The shape is slightly deteriorated C: The shape is significantly degraded or unresolved

[Table 9] Resistor composition Flushing fluid characteristics result type First organic solvent Second organic solvent Other organic solvents bp1-bp2 (℃) Sensitivity (μC/cm ² ) Analysis frame number Residue shape type structure type structure type structure Example 1 1 S-1 Diisobutyl ketone Branched Isoamyl formate Branched - - 44.0 157 5 without A Example 2 2 S-2 Dibutyl Carbonate Straight Isoamyl formate Branched - - 83.0 177 4 without A Example 3 3 S-3 Hexyl propionate Straight Diisopropyl ketone Branched - - 61.0 177 4 without A Example 4 4 S-4 Isopropyl caproate Branched Isopropyl propionate Branched - - 60.0 157 3 without A Example 5 5 S-6 Diisobutyl ketone Branched Dipropyl carbonate Straight - - 1.0 177 3 without A Example 6 6 S-7 Diisobutyl ketone Branched Diethyl carbonate Straight - - 42.0 157 4 without A Example 7 1 S-4 Isopropyl caproate Branched Isopropyl propionate Branched - - 60.0 157 5 without A Example 8 1 S-5 Mesitylene Branched Isoamyl formate Branched - - 40.0 157 5 without A Example 9 1 S-8 Mesitylene Branched Ethyl isobutyrate Branched - - 54.0 157 5 without A Example 10 1 S-9 Butyl caproate Straight Isoamyl formate Branched - - 84.0 157 4 without A Example 11 3 S-10 Butyl caproate Straight Diethyl carbonate Straight - - 82.0 177 3 without A Comparative example 1 1 - - - - - - - - 157 1 without C Comparative example 2 3 S-11 Diisobutyl ketone Branched - - - - - 157 5 Have B Comparative example 3 1 S-12 - - Isoamyl formate Branched - - - 177 1 without C Comparative example 4 3 S-13 - - - - Butyl acetate Straight - 177 0 without C Comparative example 5 3 S-14 - - - - 2-heptanone Straight - 177 0 without C Comparative example 6 1 S-15 - - - - Decane Straight - 157 4 Have B Comparative example 7 3 S-16 Diisobutyl ketone - - - Butyl acetate Straight 42.0 177 0 without C

＜Results＞ From the results shown in Table 9, it can be confirmed that when the treatment liquid of the present invention is used as a rinse liquid, the desired effect can be obtained.

From the comparison of Examples 1 and 7 to 9 and Example 10, it was confirmed that when both the first organic solvent and the second organic solvent have a branched alkyl group, the effect is more excellent. In addition, it was confirmed from the comparison with the same example that the effect is more excellent when the relationship of formula (1) is satisfied.

From the comparison between Example 3 and Example 11, it was confirmed that when the second organic solvent has a branched alkyl group, the effect is more excellent.

From the comparison between Example 4 and Example 7, it was confirmed that when the resist composition contains a resin having a hydroxystyrene-based repeating unit, the effect is more excellent.

[EUV exposure evaluation (process window evaluation): Examples 12-13 and Comparative Example 7] Using composition 7 described in Table 2, a resist pattern was formed by the following operations. Table 10 shows the details of the resist pattern formation conditions.

＜Formation of pattern＞ (Coating of resist composition and baking after coating) An organic film formation composition AL412 (manufactured by Brewer Science, Inc.) was applied on a 12-inch silicon wafer and baked at 205°C for 60 seconds to form an organic film with a thickness of 20 nm. The resist composition 7 described in Table 2 was coated thereon, and baked under the conditions described in Table 10 below (post-coating baking) to form a resist film with a thickness of 40 nm.

(Exposure) The EUV exposure device was used to form the resist film on the wafer (wafer with resist film) in the above manner, and the focus and exposure amount were changed to expose the HP (half pitch) 28nm dot pattern . Specifically, the focus condition is set to change 0.02 μm every time within the range of -0.06 to 0.10 μm, and there are 9 types of focus conditions in total. Further, the exposure condition is set in the range of 41 ~ 69mJ / cm ² in each exposure amount of 1mJ / cm ² is changed, and the exposure conditions for a total of 29 species. In addition, 9 types of focus and 29 types of exposure conditions were combined, and each exposure was performed under a total of 261 types of exposure conditions.

(Bake after exposure) After exposure, the wafer was taken out of the exposure device, and immediately used a hot plate equipped with a developing device (ACT12 manufactured by Tokyo Electron Limited), and baked at 110°C (post-exposure baking) for 60 seconds.

(Development process) Using a developing device (ACT12 manufactured by Tokyo Electron Limited), while rotating the wafer at 50 rpm, the developer solution (23°C) described in Table 10 was sprayed on the wafer at a flow rate of 200 mL/min for 10 seconds. Developed.

(Flushing process) Then, while rotating the wafer at 50 rpm, the rinsing liquid (23° C.) described in Table 10 was sprayed on the wafer at a flow rate of 200 mL/min for 5 seconds to perform a rinsing process. Among them, in Comparative Example 7, no rinsing treatment was performed. Finally, the wafer was rotated at a high speed of 2000 rpm for 60 seconds to dry the wafer.

[Table 10] Resistor composition exposure Bake after coating Baking after exposure Developer Rinsing fluid Example 12 7 EUV 120℃×60 seconds 110℃×60 seconds S-13 S-1 Example 13 7 EUV 120℃×60 seconds 110℃×60 seconds S-13 S-2 Comparative example 8 7 EUV 120℃×60 seconds 110℃×60 seconds S-13 -

<Evaluation> The obtained pattern was evaluated for the following items. Table 11 shows the details of the results. The “sensitivity” column in the table shows the irradiation energy (exposure amount, unit: mJ/cm ² ) when analyzing a dot pattern of HP (half pitch) 28 nm.

(Evaluation of process margin (analysis, analysis frame number)) The obtained pattern was observed using a scanning electron microscope (S-9380 manufactured by Hitachi, Ltd.). The number of frames that the above-mentioned dot pattern can be analyzed without any problems (the number of analysis frames; the number of exposures and the number of focal depths that can be analyzed without problems) are counted. Based on the result of the exposure performed in the above (exposure), the number of analysis frames under the focus with the largest number of analysis frames is evaluated as the number of analysis frames in the exposure direction. In addition, based on the exposure results performed in the above (exposure), the number of analysis frames at the exposure with the largest number of analysis frames is evaluated as the number of analysis frames in the depth of focus direction.

(Residue (residue inhibition)) A scanning electron microscope (S-9260 manufactured by Hitachi, Ltd.) was used to observe the unexposed part of the wafer, and it was confirmed whether there was any residue.

[Table 11] Sensitivity Analysis frame number Residue inhibition (ΜC/cm ² ) Exposure direction/focus depth direction Example 12 55 5/5 No residue Example 13 55 5/5 No residue Comparative example 8 55 1/1 No residue

From the above evaluation results, it was confirmed that the pattern forming method using the treatment liquid of the present invention can form ultra-fine-sized patterns, and can be preferably used.

The treatment liquid of the present invention is not only used as the above-described rinse liquid, but also when used as a developer, it can achieve both improvement in analysis performance and residue suppression.

In Example 1, even if the developer was changed to 3:2 (volume ratio) of S-13 and S-1 and developed, the pattern was similarly obtained.

without.

Fig. 1 is a photomicrograph showing an example of patterns produced in Examples and Comparative Examples.

Claims (9)

A treatment liquid used for at least one of the development and cleaning of the resist film obtained from the sensitizing radiation or the radiation-sensitive composition after exposure to the resist film patterning treatment liquid, the aforementioned treatment Liquid contains: The first organic solvent; and the second organic solvent, The first organic solvent is selected from the group consisting of a ketone solvent having 8 to 10 carbon atoms, an ester solvent having 8 to 10 carbon atoms other than acetate, and an aromatic hydrocarbon solvent having 8 to 10 carbon atoms At least one of The second organic solvent includes at least one selected from the group consisting of a ketone solvent having 5 to 7 carbon atoms and an ester solvent having 5 to 7 carbon atoms other than acetate. The treatment liquid described in claim 1, wherein The aforementioned first organic solvent is selected from the group consisting of 2,5-dimethyl-3-hexanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, diisobutyl ketone, 2,2 ,4,4-Tetramethyl-3-pentanone, dibutyl carbonate, heptyl formate, 2-ethylhexyl formate, isoamyl propionate, hexyl propionate, butyl butyrate, isobutyrate Butyl ester, butyl isobutyrate, ethyl caproate, propyl caproate, isopropyl caproate, butyl caproate, isobutyl caproate, 3,3-dimethylbutane ethyl ester, all three At least one of the group of toluene, cumene, trimethylbenzene, 1,2,4,5-tetramethylbenzene, and p-cymene. The treatment liquid described in claim 1 or claim 2, wherein The aforementioned second organic solvent comprises a solvent selected from the group consisting of 3-methyl-2-butanone, 3,3-dimethyl-2-butanone, 2-methyl-3-pentanone, 3-methyl-2-pentanone Ketone, 4-methyl-2-pentanone, diisopropyl ketone, 2-methyl-3-hexanone, 5-methyl-2-hexanone, pentyl formate, isoamyl formate, third formic acid At least one of the group of pentyl ester, hexyl formate, isopropyl propionate, isobutyl propionate, ethyl isobutyrate, diethyl carbonate, and dipropyl carbonate. The treatment liquid described in claim 1 or claim 2, wherein The aforementioned first organic solvent and the aforementioned second organic solvent satisfy the relationship of formula (1), Formula (1): 5.0℃＜bp1-bp2＜100.0℃ bp1: the boiling point of the aforementioned first organic solvent bp2: the boiling point of the aforementioned second organic solvent. The treatment liquid described in claim 1 or claim 2, wherein At least one of the first organic solvent and the second organic solvent has a branched alkyl group. The treatment liquid described in claim 1 or claim 2, wherein Both the first organic solvent and the second organic solvent have a branched alkyl group. The treatment liquid described in claim 1 or claim 2, wherein The aforementioned sensitizing radiation or radiation-sensitive composition includes a resin having a hydroxystyrene-based repeating unit. A pattern forming method, which has: The resist film forming process of using the aforementioned sensitizing radiation or radiation-sensitive composition to form the resist film; Exposure process for exposing the aforementioned resist film; and A treatment process for treating the exposed resist film with the treatment liquid described in any one of claim 1 to claim 7. A pattern forming method, which has: The resist film forming process of using the aforementioned sensitizing radiation or radiation-sensitive composition to form the resist film; Exposure process for exposing the aforementioned resist film; and In the process of processing the exposed resist film, in the pattern forming method, The aforementioned processing process has: The developing process of developing with a developing solution; and The washing process of washing with washing liquid, The aforementioned rinse liquid is the treatment liquid described in any one of Claim 1 to Claim 7.

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