KR20140050053A - Photoresist composition - Google Patents

Abstract

An object of the present invention is to provide a photoresist composition that satisfies basic characteristics such as sensitivity sufficiently and is excellent in MEEF, DOF, and LWR. The present invention provides a photoresist composition containing a polymer having an [A] acid generator and an acid generator having at least one structure selected from the group consisting of a [B] lactone structure, a cyclic carbonate structure, a sultone structure and an alicyclic structure. to be. The acid generator [B] preferably has at least one structure selected from the group consisting of lactone structures and sultone structures. In addition, the polymer [A] may include at least one structural unit selected from the group consisting of structural units (I) represented by the following general formula (1) and structural units (II) represented by the following general formula (2). have.

Description

Photoresist composition {PHOTORESIST COMPOSITION}

The present invention relates to a photoresist composition.

In the field of microfabrication for manufacturing integrated circuit devices, etc., in order to obtain higher integration degree, irradiation of short wavelength radiation (exposure) represented by KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), or the like is used. Development of lithography techniques is underway. As the resist material adapted to these exposure light sources, high sensitivity, high resolution, and the like are required, and a chemically amplified photoresist composition containing a component having an acid dissociable group and an acid generator which generates an acid by irradiation with radiation is usually used. (Refer patent document 1).

On the other hand, in recent years in which device miniaturization is further progressing, techniques using X-rays, electron beams (EB), extreme ultraviolet rays (EUV), and the like, which are shorter than excimer lasers, have been studied. However, when a finer resist pattern is formed using a conventional photoresist composition, it is considered appropriate that the acid diffusion distance (hereinafter referred to as "diffusion length") in the resist film is somewhat short. Due to the inadequate diffusion length, it is possible to sufficiently satisfy lithography characteristics such as Mask Error Enhancemnt Factor (MEEF), Depth Of Focus, and Line Width Roughness (LWR), which are indicators of mask error tolerance. What is impossible is reality.

In view of such a situation, the photoresist composition for forming a finer resist pattern is desired to not only improve basic characteristics such as sensitivity and resolution, but also improve MEEF, DOF, and LWR.

Japanese Patent Publication No. 59-45439

The present invention has been made on the basis of the above circumstances, and an object thereof is to provide a photoresist composition that satisfies not only basic characteristics such as sensitivity but also MEEF performance, DOF, and LWR.

In order to solve the above problems,

[A] a polymer having an acid generator (hereinafter also referred to as "[A] polymer"), and

[B] Photoresist containing an acid generator (hereinafter also referred to as "[B] acid generator") having at least one structure selected from the group consisting of a lactone structure, a cyclic carbonate structure, a sultone structure, and an alicyclic structure Composition.

In the photoresist composition, the acid generator is present in the polymer [A], so that the acid generated by exposure becomes uniform, and the diffusion of acid from the exposed portion to the unexposed portion is controlled appropriately. In addition, since the acid generator [B] has a bulky structure such as a lactone structure, a cyclic carbonate structure, a sultone structure, and an alicyclic structure, the photoresist composition can shorten the diffusion length of the acid. As a result of this, the diffusion of the acid is properly controlled, and the acid can be uniformly and sufficiently functioned in the exposed portion, so that the photoresist composition satisfies not only basic characteristics such as sensitivity but also MEEF performance, DOF and LWR.

It is preferable that the acid generator (B) has at least one structure selected from the group consisting of lactone structures and sultone structures. As described above, when the acid generator [B] has a lactone structure and a sultone structure, the photoresist composition can appropriately shorten the diffusion length of the acid.

In addition, the acid generator [B] is also excellent in compatibility with the polymer [A], and therefore can function efficiently in the photoresist composition. As a result of these, the photoresist composition has better MEEF performance, DOF and LWR.

The polymer (A) may include at least one structural unit selected from the group consisting of structural units (I) represented by the following general formula (1) and structural units (II) represented by the following general formula (2).

(In formula (1), R ^p1 is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or an alkyl group having 1 to 3 carbon atoms. R ^p2 is a divalent organic group. A plurality of Rf's are each independently a hydrogen atom or a fluorine atom. Or a fluorinated alkyl group having 1 to 3 carbon atoms, n is an integer of 0 to 6. M ⁺ is an onium cation.

In formula (2), R ^p3 is a hydrogen atom, a fluorine atom, a trifluoromethyl group or an alkyl group having 1 to 3 carbon atoms. R ^p4 , R ^p5 and R ^p6 are each independently an organic group having 1 to 10 carbon atoms. and m is an integer of 0 to 3. When m is 2 or 3, a plurality of R ^p4 may be the same or different, respectively. A is a single bond, a methylene group, a C2-C10 alkylene group, a C2-C10 alkyleneoxy group, or a C6-C10 arylene group. X ⁻ is a sulfonate anion, carboxylate anion or amide anion.)

[A] The polymer itself has an ionic acid generator having the specific structure, so that the photoresist composition can distribute the acid uniformly in the polymer chain and control the diffusion of acid from the exposed portion to the unexposed portion. In addition, the hydrophilicity of the exposed portion is increased. Thereby, since the reactivity with a developing solution in an exposure part improves further, the said photoresist composition is more excellent in MEEF performance, DOF, and LWR.

[A] The polymer may include a structural unit (I) represented by the general formula (1), and M ⁺ of the general formula (1) may be represented by the following general formula (3).

(In formula (3), R ^p7 to R ^p9 are each independently a hydrocarbon group having 1 to 30 carbon atoms, provided that R ^p7 and R ^p8 are bonded to each other to form a cyclic structure together with the sulfur atom to which they are bonded. Some or all of the hydrogen atoms of the hydrocarbon group may be substituted.)

Since the ionic acid generator which the structural unit (I) represented by the said General formula (1) has the cation represented by the said General formula (3), the said photoresist composition is excellent in MEEF performance, DOF, and LWR.

[A] The polymer may include a structural unit (I) represented by the general formula (1), and M ⁺ of the general formula (1) may be represented by the following general formula (4).

(In formula (4), R ^p10 to R ^p12 are each independently a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a group having an -SR ^x group or a plurality of hetero atoms. R ^x is an alkyl group or an aryl group. Provided that some or all of the hydrogen atoms possessed by the alkyl, cycloalkyl, alkoxy and aryl groups may be substituted, a is an integer from 1 to 5. b and c are each independently an integer from 0 to 5 to be.)

Since the ionic acid generator which the structural unit (I) represented by the said General formula (1) has the cation represented by the said General formula (4), the said photoresist composition is excellent in MEEF performance, DOF, and LWR.

At least one of the R ^p10 to R ^p12 is preferably a group represented by the following general formula (4-1) or the following general formula (4-2).

(In Formulas (4-1) and (4-2), R ^x is the same as that of Formula (4).)

The photoresist composition contains the [A] polymer having an onium cation containing a group of the specific structure, whereby the photoresist composition is more excellent in MEEF performance, DOF and LWR.

[A] The polymer may include a structural unit (II) represented by the above formula (2), and X ⁻ in the above formula (2) may be represented by the following formula (5).

(In formula (5), R ^p13 is a monovalent organic group having a fluorine atom.)

Since the ionic acid generator which structural unit (II) represented by the said General formula (2) has an anion represented by the said General formula (5), the said photoresist composition is further excellent in MEEF performance, DOF, and LWR.

[A] It is preferable that a polymer further contains structural unit (III) represented by following General formula (6).

(In formula (6), R <^1> is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a C1-C3 alkyl group. R <^2> -R <^4> is respectively independently a C1-C4 alkyl group or C4-C20 However, R ³ and R ⁴ may be bonded to each other to form a divalent alicyclic group having 4 to 20 carbon atoms with the carbon atom to which they are bonded.)

The structural unit (III) represented by the formula (6) has an acid dissociable group that is easily dissociated by the action of an acid. [A] The polymer further includes the structural unit (III) containing such an acid dissociable group in addition to the structural unit (I) or the structural unit (II) having an acid generator, whereby the acid generated from the acid generator by exposure is near. The acid dissociable group of can be dissociated efficiently. Therefore, this photoresist composition is excellent in sensitivity and can form a favorable fine pattern.

The polymer (A) preferably further includes at least one structural unit (IV) selected from the group consisting of a structural unit having a lactone structure, a structural unit having a cyclic carbonate structure, and a structural unit having a sultone structure.

[A] The photoresist composition, wherein the polymer further comprises at least one structural unit (IV) selected from the group consisting of a structural unit having a lactone structure, a structural unit having a cyclic carbonate structure, and a structural unit having a sultone structure. It is excellent in adhesiveness with respect to a silver substrate, and can form a favorable fine pattern.

It is preferable that the photoresist composition further contains an [C] acid diffusion control agent.

The photoresist composition further contains an acid diffusion control agent [C], whereby acid diffusion can be more appropriately controlled, and as a result, MEEF performance, DOF, and LWR are more excellent.

[C] The acid diffusion control agent is preferably a photodegradable base. Since the photodegradable base has a property of decomposing upon exposure to lose acid diffusion control ability, the photoresist composition has a photodegradable base as the [C] acid diffusion control agent, thereby making it specific in the unexposed part. Acid diffusion can be controlled. As a result, the photoresist composition is more excellent in MEEF performance, DOF and LWR.

As described above, since the photoresist composition of the present invention contains a polymer having an acid generator and an acid generator having a lactone structure, a sultone structure, etc., it satisfies basic characteristics such as sensitivity, MEEF performance, DOF and LWR is excellent. Therefore, by using this photoresist composition, it becomes possible to form a fine pattern with high precision.

1 is a plan view schematically showing the shape of a line and space pattern.
2 is a cross-sectional view schematically showing the shape of the line and space pattern.

&Lt; Photoresist composition >

The photoresist composition contains the [A] polymer and the [B] acid generator. Moreover, [C] acid diffusion control agent is contained as a suitable component. Moreover, you may further contain other arbitrary components, unless the effect of this invention is impaired. Hereinafter, each component will be described in detail.

<[A] Polymer>

The polymer (A) has an acid generator. Here, an acid generator means group which generate | occur | produces an acid by the exposure in a pattern formation process. [A] Since the polymer itself has an acid generator, the acid generated by exposure can be uniformly distributed in the polymer chain, and the diffusion of acid from the exposed portion to the unexposed portion is controlled. As a result, the photoresist composition is excellent in MEEF performance, DOF, and LWR because the acid can be uniformly and fully functioned in the exposed portion.

The polymer (A) preferably includes a structural unit (I) represented by the above formula (1) or a structural unit (II) represented by the above formula (2) as a structural unit having an acid generator. Moreover, it is preferable to include a structural unit (III) and a structural unit (IV), and unless it is impairing the effect of this invention, you may have structural units other than structural unit (I)-structural unit (IV). Hereinafter, each structural unit will be described in detail.

[Structural unit (I)]

Structural unit (I) is represented by the said General formula (1).

In said Formula (1), R <^p1> is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a C1-C3 alkyl group. R ^p2 is a divalent organic group. A plurality of Rf's are each independently a hydrogen atom, a fluorine atom or a fluorinated alkyl group having 1 to 3 carbon atoms. n is an integer of 0 to 6; M ⁺ is an onium cation.

As a C1-C3 alkyl group represented by said R <^p1> , a methyl group, an ethyl group, and a propyl group are mentioned. Especially, a methyl group is preferable. As R ^p1 , a hydrogen atom and a methyl group are preferable.

As the divalent organic group represented by the R ^p2, for example, a hydrocarbon group, -R -R ^{p21 p22} having 1 to 20 carbon atoms - and the like can be a group represented by the. R ^p21 is a hydrocarbon group having 1 to 20 carbon atoms, and R ^p22 is -O-, -CO-, -COO-, -OCO-, -NH-, -NHCO-, -CONH-, or -NHCOO-.

As a C1-C20 hydrocarbon group represented by said R <^p2> , for example,

Chain hydrocarbon groups such as methylene group, ethanediyl group, propanediyl group, butanediyl group, pentanediyl group, hexanediyl group and decanediyl group;

Alicyclic groups in which two hydrogen atoms have been removed from alicyclic structures such as cyclopentane, cyclohexane, dicyclopentane, tricyclodecane, tetracyclododecane, and adamantane;

Aromatic hydrocarbon groups, such as a phenylene group, a naphthylene group, and a biphenylene group, etc. are mentioned.

However, one part or all part of the hydrogen atom which these hydrocarbon group has may be substituted by the fluorine atom.

Among them, a chain hydrocarbon group and an alicyclic group are preferable, and a chain hydrocarbon group is more preferable. Especially, methylene group, ethanediyl group, propanediyl group, butanediyl group, and pentanediyl group are more preferable, and a methylene group and an ethanediyl group are especially preferable.

Examples of the hydrocarbon group having 1 to 20 carbon atoms represented by R ^p21 include the same groups as the groups exemplified as the hydrocarbon group having 1 to 20 carbon atoms represented by R ^p2 .

Examples of the group represented by -R ^p21 -R ^p22 -are -CH ₂ -O-, -CH ₂ -CO-, -CH ₂ -COO-, -CH ₂ -OCO-, and -CH ₂ -NH. -, -CH ₂ -NHCO-, -CH ₂ -CONH-, -CH ₂ -NHCOO-, -CH ₂ -CH ₂ -O-, -CH ₂ -CH ₂ -CO-, -CH ₂ -CH _2- COO-, -CH ₂ -CH ₂ -OCO-, -CH ₂ -CH ₂ -NH-, -CH ₂ -CH ₂ -NHCO-, -CH ₂ -CH ₂ -CONH-, -CH ₂ -CH _2- NHCOO-, -CH ₂ -CH ₂ -CH ₂ -O-, -CH ₂ -CH ₂ -CH ₂ -COO-, -CH ₂ -CH ₂ -CH ₂ -OCO-, -CH ₂ -CH ₂ -CH ₂ -NH-, -CH ₂ -CH ₂ -CH ₂ -NHCO-, -CH ₂ -CH ₂ -CH ₂ -CONH-, -CH ₂ -CH ₂ -CH ₂ -NHCOO-, -CH ₂ -CH ₂ -CHF-NHCOO-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -O-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -CO-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -COO-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -OCO-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -NH-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -NHCO -, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -CONH-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -NHCOO-, -CH ₂ -CH ₂ -CH ₂ -CHF-NHCOO-,- CH ₂ -CH ₂ -CH ₂ -CH ₂ -CH ₂ -CONH-, -CH ₂ -CH ₂ -CH ₂ -CH ₂ -CH ₂ -NHCOO-, -CH ₂ -CH ₂ -CH ₂ -CH _2- CHF-NHCOO- etc. are mentioned.

Among these, -CH ₂ -NHCOO-, -CH ₂ -CH ₂ -NHCOO- and -CH ₂ -CH ₂ -CH ₂ -NHCOO- are preferable, and -CH ₂ -CH ₂ -NHCOO- is more preferable. Moreover, it is preferable that R <^p21> is couple | bonded with the ester group in the said ^General formula (1) in the group represented by said -R <^p21> -R <^p22> .

Examples of the fluorinated alkyl group having 1 to 3 carbon atoms represented by Rf include monofluoromethyl group, difluoromethyl group, trifluoromethyl group, 1-fluoroethyl group, 1,2-difluoroethyl group, 1,1 And a 2,2-tetrafluoroethyl group.

As said Rf, a hydrogen atom and a fluorine atom are preferable, and a fluorine atom is more preferable.

As said n, 0-4 are preferable, 1-3 are more preferable, and 1 and 2 are more preferable.

Examples of the onium cation represented by M ⁺ include sulfonium cations, iodonium cations, and the like, and sulfonium cations represented by the general formula (3) and iodonium represented by the following general formula (7) At least one onium cation selected from the group consisting of cations is preferred.

In said Formula (3), R <^p7> -R <^p9> is a C1-C30 hydrocarbon group each independently. However, R ^p7 and R ^p8 may be bonded to each other to form a cyclic structure together with the sulfur atom to which they are bonded. Some or all of the hydrogen atoms which the said hydrocarbon group has may be substituted.

As said C1-C30 hydrocarbon group represented by R <^p7> -R <^p9> in the said ^General formula (3), it is a, for example.

Monovalent chain hydrocarbon groups such as methyl group, ethyl group, n-propyl group, n-butyl group and n-pentyl group;

Monovalent alicyclic groups such as cyclobutyl group, cyclopentyl group, cyclohexyl group, dicyclopentyl group, tricyclodecyl group, tetracyclododecyl group and adamantyl group;

Monovalent hydrocarbon group which has a part of the said alicyclic structure;

Monovalent aromatic hydrocarbon groups such as phenyl group, naphthyl group, anthryl group and biphenyl group;

The monovalent hydrocarbon group etc. which have an aromatic ring in one part are mentioned. Among these, monovalent aromatic hydrocarbon groups, such as a phenyl group, a naphthyl group, an anthryl group, and a biphenyl group, are preferable and a phenyl group is more preferable.

And the like - The substituent which may have groups wherein the hydrocarbon group, for example a halogen atom, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, a halogenated hydrocarbon group, an alkyl group, an alkoxyl group, an amino group, a thiol group, an organic sulfonyl group (RSO ₂₎ Can be. R is an alkyl group, a cycloalkyl group or an aryl group. Among them, a hydroxyl group, an alkyl group, an alkoxyl group and a cyclohexylsulfonyl group are preferable, and a cyclohexylsulfonyl group is more preferable.

Of the sulfonium cations represented by the general formula (3), the sulfonium cations represented by the general formula (4) are more preferable.

In formula (4), R ^p10 to R ^p12 are each independently a group having a hydroxy group, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an -SR ^x group or a plurality of hetero atoms. R ^x is an alkyl group or an aryl group. However, one part or all part of the hydrogen atom which the said alkyl group, a cycloalkyl group, an alkoxy group, and an aryl group have may be substituted. a is an integer of 1-5. b and c are each independently an integer of 0-5.

As said R <^p10> -R <^p12> , the group in which at least one is represented by the said ^General formula (4-1) and the said General formula (4-2) is preferable.

As a sulfonium cation represented by the said General formula (3), the cation represented by the following general formula (i-1)-(i-23), etc. are mentioned, for example.

Among them, sulfonium cations represented by (i-1) and (i-23) are preferable.

In said general formula (7), R <^p14> is a C1-C30 hydrocarbon group or a heterocyclic organic group of ^4-30 carbon atoms each independently. However, two R ^{p14 's} may be bonded to each other to form a cyclic structure together with an iodine atom. In addition, one part or all part of the hydrogen atom which the said hydrocarbon group and heterocyclic organic group have may be substituted.

Examples of the hydrocarbon group having 1 to 30 carbon atoms represented by R ^p14 in the general formula (7) include the same groups as the groups exemplified as the hydrocarbon groups having 1 to 30 carbon atoms represented by R ^p7 to R ^p9 in the general formula (3). Can be.

As said R <^p14> , among these, monovalent aromatic hydrocarbon groups, such as a phenyl group, a naphthyl group, an anthryl group, and a biphenyl group, are preferable, and a phenyl group is more preferable.

Wherein there may be mentioned hydrocarbon group and heterocyclic group as the organic substituent which may have, the general formula (3) in the R group of any ^p7 to the same group for example as a substituent which may have a hydrocarbon group represented by R ^p9. Especially, a halogen atom, a nitro group, a halogenated hydrocarbon group, an alkyl group, and an alkoxyl group are preferable.

As the monovalent onium cation represented by M ⁺ , the sulfonium cation represented by the general formula (3) is preferable, and the sulfonium cation represented by the general formula (4) is more preferable, and among these, the general formula (i-1) And sulfonium cations represented by (i-23) are more preferred.

In addition, the monovalent onium cation represented by M <+> in said General formula (1) is manufactured according to the general method described, for example in Advances in Polymer Science, Vol. 62, p.1-48 (1984). can do.

As structural unit (I) represented by the said General formula (1), the structural unit represented by following General formula (1-1)-(1-8) etc. are mentioned, for example.

In said formula, R <^p1> is synonymous with the said ^General formula (1).

Among them, the structural units represented by the formulas (1-1) to (1-4) are preferable.

As a monomer compound which provides the structural unit represented by the said General formula (1), the compound represented by following General formula (1 ') is mentioned, for example.

In said Formula (1 '), R <^p2> , Rf, n, and M <^+> are synonymous with the said Formula (1).

The compound represented by the said general formula (1 ') can be synthesize | combined by a well-known method.

As a compound represented by the said General formula (1 '), the compound etc. which are represented by following General formula (1'-1)-(1'-8) are mentioned, for example.

In the polymer [A], the content of the structural unit (I) is preferably 1 mol% or more and 50 mol% or less, and 1 mol% or more and 30 mol% or less with respect to all the structural units constituting the polymer [A]. More preferably, 1 mol% or more and 10 mol% or less are more preferable. When the content rate of structural unit (I) exceeds 50 mol%, there exists a possibility that pattern formation property may fall. Moreover, when it is less than 1 mol%, the developing solution insoluble of an exposed part may become inadequate and a favorable pattern may not be obtained. In addition, the polymer [A] may have one or two structural units (I).

[Structural unit (II)]

Structural unit (II) is represented by the said General formula (2).

In said Formula (2), ^Rp3 is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a C1-C3 alkyl group. R ^p4 , R ^p5 and R ^p6 are each independently an organic group having 1 to 10 carbon atoms. and m is an integer of 0 to 3. When m is 2 or 3, a plurality of R ^p4 may be the same or different, respectively. A is a single bond, an alkanediyl group having 1 to 10 carbon atoms, an alkyleneoxy group having 2 to 10 carbon atoms, or an arylene group having 6 to 10 carbon atoms.

X ⁻ is a sulfonate anion, carboxylate anion or amide anion.

In said Formula (2), a methyl group, an ethyl group, and a propyl group are mentioned as a C1-C3 alkyl group represented by ^Rp3 . Especially, a methyl group is preferable. As R ^p3 , a hydrogen atom and a methyl group are preferable.

Examples of the alkanediyl group having 1 to 10 carbon atoms represented by A include, for example, a methylene group, an ethylene group, a 1,3-propylene group, a 1,2-propylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, Heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, 1-methyl-1,3-propylene group, 2-methyl-1,3-propylene group, 2-methyl-1,2-propylene group, 1 -Methyl-1,4-butylene group, 2-methyl-1,4-butylene group, etc. are mentioned.

Examples of the alkyleneoxy group having 2 to 10 carbon atoms represented by A include, for example, an ethyleneoxy group, a 1,3-propyleneoxy group, a 1,2-propyleneoxy group, a tetramethyleneoxy group, a pentamethyleneoxy group, and hexa © tylene Oxy group, heptamethyleneoxy group, octamethyleneoxy group, nonamethyleneoxy group, decamethyleneoxy group, 1-methyl-1,3-propyleneoxy group, 2-methyl-1,3-propyleneoxy group, 2-methyl -1, 2- propylene oxy group, a 1-methyl- 1, 4- butylene oxy group, 2-methyl- 1, 4- butylene oxy group, etc. are mentioned.

As a C6-C10 arylene group represented by said A, a phenylene group, a naphthylene group, anthylene group, a phenanthryl group, etc. are mentioned, for example.

Among them, alkyleneoxy groups such as ethyleneoxy group and propyleneoxy group are preferable from the viewpoint of excellent stability as a compound.

Examples of the R ^{p4, p5} and R a monovalent organic group having 1 to 10 carbon atoms represented by R ^p6, for example, an alkyl group having 1 to 10 carbon atoms, an alkoxy group, an aryl group, and the like.

As said alkyl group, a methyl group, an ethyl group, n-propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, a pentyl group, a hexyl group, a hydroxide, for example A hydroxymethyl group, a hydroxyethyl group, and a trifluoromethyl group are mentioned.

As said alkoxy group, a methoxy group, an ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group, n-pentyloxy group, neopentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, 2-ethylhexyloxy group, n-nonyloxy group, n-decyloxy group, etc. are mentioned. Can be.

As said aryl group, a phenyl group, a naphthyl group, etc. are mentioned, for example.

In said monovalent organic group, as R <^p4> , an alkoxy group is preferable and especially a methoxy group is more preferable. As R ^p5 and R ^p6 , an aryl group is preferable, a phenyl group and a naphthyl group are more preferable, and a phenyl group is more preferable.

As m, 0 and 1 are preferable and 0 is more preferable.

Wherein X ^- As, a sulfonate anion and an anion-carboxylate is preferred, more preferably a sulfonate anion. Especially, the sulfonate anion represented by the said General formula (5) is more preferable.

In said Formula (5), ^Rp13 is a monovalent organic group which has a fluorine atom.

As a monovalent organic group in the monovalent organic group which has a fluorine atom represented by said R <^p13> , a C1-C10 linear alkyl group, the hydrocarbon group which has a C6-C20 alicyclic skeleton, etc. are mentioned, for example. . Moreover, you may have -O-, -S-, -C (O) O-, or -C (O) N- between the carbon-carbon bonds of the said linear alkyl group and the hydrocarbon group which has alicyclic skeleton. Some or all of the hydrogen atoms of the monovalent organic group having a fluorine atom are substituted with an alkyl group, an aryl group, an aralkyl group, a cycloalkyl group, a halogenated alkyl group, a halogenated aryl group, a halogenated aralkyl group, an oxidized cycloalkyl group, a halogenated cycloalkyl group, or the like. There may be.

As a C1-C10 linear alkyl group which has a fluorine atom represented by said R <^p13> , For example, a trifluoromethyl group, a trifluoroethyl group, a pentafluoropropyl group, a hexafluoroisopropyl group, and hexafluoro (2 -Methyl) isopropyl group, heptafluorobutyl group, heptafluoroisopropyl group, octafluoroisobutyl group, nonafluorohexyl group, nonafluorobutyl group, perfluoro isopentyl group, perfluoro jade Tyl group, a perfluoro (trimethyl) hexyl group, etc. are mentioned. Among these, nonafluorobutyl groups are preferable.

As a hydrocarbon group which has a C6-C20 alicyclic skeleton which has a fluorine atom represented by said R <^p13> , group represented by a following formula is mentioned, for example.

-O-, -S-, -C (O) O- or -C (O) N between the carbon-carbon bonds of the chain alkyl group having a fluorine atom represented by R ^p13 and the hydrocarbon group having an alicyclic skeleton As group which has-, the group represented by a following formula is mentioned, for example.

As a sulfonate anion represented by the said General formula (5), the sulfonate anion etc. represented by following General formula (5-1)-(5-17) are mentioned.

Among them, sulfonate anions represented by the general formula (5-1) are preferred.

As structural unit (II) represented by the said General formula (2), the structural unit represented by following General formula (2-1)-(2-18), etc. are mentioned.

In said formula, R <^p3> is synonymous with the said ^General formula (2).

Among these, structural units represented by the formulas (2-3), (2-10), (2-11) and (2-12) are preferable.

As a monomer compound which provides the structural unit represented by the said General formula (2), the compound etc. which are represented by following General formula (2 ') are mentioned.

In said Formula (2 '), A, ^Rp4 , ^Rp5 , ^Rp6 , m, and X <^-> are synonymous with the said Formula (2).

As a compound represented by the said General formula (2 '), the compound etc. which are represented by following General formula (2'-1)-(2'-18) are mentioned, for example.

In the polymer [A], as the content ratio of the structural unit (II), 1 mol% or more and 50 mol% or less are preferable, and 1 mol% or more and 30 mol% or less with respect to all the structural units constituting the [A] polymer. More preferably, 1 mol% or more and 10 mol% or less are more preferable. When the content rate of structural unit (II) exceeds 50 mol%, there exists a possibility that pattern formation property may fall. Moreover, when it is less than 1 mol%, the developing solution insoluble of an exposed part may become inadequate and a favorable pattern may not be obtained. In addition, the polymer [A] may have one kind or two or more kinds of the structural unit (II).

[Structural unit (III)]

[A] It is preferable that a polymer further contains structural unit (III) represented by the said General formula (6). Structural unit (III) represented by the said General formula (6) is a structural unit in which the carbon atom couple | bonded with an ester group is tertiary carbon, and has an acid dissociable group which is easy to dissociate by the action of an acid.

In general formula (6), R <^1> is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a C1-C3 alkyl group. R ² to R ⁴ are each independently an alkyl group having 1 to 4 carbon atoms or an alicyclic group having 4 to 20 carbon atoms. However, R ³ and R ⁴ may be bonded to each other to form a divalent alicyclic group having 4 to 20 carbon atoms with the carbon atom to which they are bonded.

As a C1-C4 alkyl group represented by said R <^2> -R <^4> , for example, a methyl group, an ethyl group, n-propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group and t-butyl group.

As a C4-C20 alicyclic group represented by said R <^2> -R <^4> , or a C4-C20 alicyclic group which R <^3> and R <^4> combine with each other and may form together with the carbon atom to which they are bonded, a Polycyclic alicyclic groups having a cycloalkane skeleton such as a tantan skeleton and a norbornane skeleton; And monocyclic alicyclic groups having a cycloalkane skeleton such as cyclopentane and cyclohexane. Among these, alicyclic groups having 10 or less carbon atoms constituting the ring are preferable. In addition, these groups may be substituted by 1 or more types of a C1-C10 linear, branched, or cyclic alkyl group, for example.

Examples of the structural unit (III) include a structural unit represented by the following formula.

In said formula, R <^1> is synonymous with the said General formula (6). R ² is an alkyl group having 1 to 4 carbon atoms. m is an integer of 1 to 6;

Among them, the structural units represented by the following formulas (6-1) to (6-18) are preferable, and (6-3) is more preferable.

In said formula, R <^1> is synonymous with the said Formula (6).

In the polymer [A], the content of the structural unit (III) is preferably 10 mol% or more and 80 mol% or less, and 20 mol% or more and 60 mol% or less with respect to all the structural units constituting the polymer [A]. More preferred. When the content rate of structural unit (III) exceeds 80 mol%, there exists a possibility that MEEF performance, DOF, and LWR may become inadequate. Moreover, when it is less than 10 mol%, there exists a possibility that a favorable pattern may not be obtained. In addition, the polymer [A] may have one or two or more structural units (III).

As a monomer which provides a structural unit (III), for example, (meth) acrylic acid-bicyclo [2.2.1] hept-2-yl ester and (meth) acrylic acid-bicyclo [2.2.2] oct-2-yl Ester, (meth) acrylic acid-tricyclo [5.2.1.0 ^2,6 ] dec-7-ylester, (meth) acrylic acid-tricyclo [3.3.1.1 ^3,7 ] dec-1- ^ylester , (meth) acrylic acid ^-Tricyclo [3.3.1.1 ^3,7 ] deck-2-yl ester, etc. are mentioned.

[Structural Unit (IV)]

[A] It is preferable that a polymer has structural unit (IV) which has at least 1 sort (s) of structure chosen from the group which consists of a lactone structure, a cyclic carbonate structure, and a sultone structure as another structural unit other than the above. When the polymer (A) has a structural unit (IV), the adhesion to the substrate or the like of the photoresist composition is improved.

Examples of the structural unit (IV) include structural units represented by the following formulas.

In said formula, R <^5> is a hydrogen atom or a methyl group. R ⁶ is a hydrogen atom or a methyl group. R ⁷ and R ⁸ are each independently a hydrogen atom or a methoxy group. Z ₁ is a group formed by a single bond, a methylene group, an ester group or a combination thereof. Z ₂ is a methylene group or an oxygen atom. b, d and e are 0 or 1.

As structural unit (IV), the structural unit represented with the following general formula is specifically preferable.

In said formula, R <^5> is a hydrogen atom or a methyl group.

In the polymer [A], the content of the structural unit (IV) is preferably 0 mol% or more and 70 mol% or less, and 10 mol% or more and 60 mol% or less with respect to all the structural units constituting the [A] polymer. Is more preferable. By making the content rate of a structural unit (IV) into such a content rate, adhesiveness with respect to the board | substrate etc. of this photoresist composition can be improved. On the other hand, when the content rate of structural unit (IV) exceeds 70 mol%, there exists a possibility that MEEF performance, DOF, and LWR may become inadequate.

As a preferable monomer which provides a structural unit (IV), the monomer as described in international publication 2007/116664 is mentioned, for example.

[Structural unit (V)]

The polymer (A) may further have a structural unit (V) containing a polar group represented by the following formula. As a "polar group" here, a hydroxyl group, a carboxyl group, a keto group, a sulfonamide group, an amino group, an amide group, a cyano group, etc. are mentioned, for example.

As a structural unit (V), the structural unit represented by a following formula is mentioned, for example.

In said formula, R <^9> is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

In the polymer [A], the content of the structural unit (V) is preferably 5 mol% or more and 80 mol% or less, and 5 mol% or more and 40 mol% or less with respect to all the structural units constituting the [A] polymer. Is more preferable. In addition, the polymer [A] may have one or two or more structural units (V).

[Structural unit (VI)]

[A] The polymer may contain other structural units (VI) derived from aromatic compounds as other structural units. As structural unit (VI), the structural unit represented by a following formula, etc. are mentioned, for example.

In said formula, R <^10a> is a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group.

In the formula (p-1) and the formula (p-2), R ^p1 is a monovalent acid dissociable group, and R ^p2 is a monovalent hydrocarbon group which may be substituted. ka is an integer of 1-3, kb is an integer of 0-4, and ka + kb <= 5. Provided that when ka is 2 to 3, R ^p1 satisfies the above definition independently of each other, and when kb is 2 to 4, R ^p2 satisfies the above definition independently of each other. R <^10b> is a hydrogen atom and a C1-C4 alkyl group.

In the formula (p-1) and the formula (p-2), examples of the monovalent acid dissociable group of R ^p1 include a 1-branched alkyl group, triorganosilyl group, triorganogeryl group, and alkoxycarbonyl group. , Acyl group, monovalent heterocyclic group, alkoxyalkyl group, benzyl group which may be substituted, and the like. Among these, as R ^p1 , tert-butyl group, benzyl group, 1-methoxyethyl group, 1-ethoxyethyl group, 1-phenoxyethyl group, 1-adamantaneoxymethyl group, trimethylsilyl group, tert-butoxycarbonyl group , tert-butoxycarbonylmethyl group, tetrahydrofuranyl group, tetrahydropyranyl group, tetrahydrothiofuranyl group, tetrahydrothiopyranyl group and the like are preferable.

In the benzene ring in the general formula (p-1) and the general formula (p-2), the bonding position of R ^p1 is not particularly limited, but is preferably 4-position. In addition, when having a plurality of benzene ring R ^p1, a combination of the binding position of R ^p1 thereof it may be any. As a monovalent hydrocarbon group in R <^p2> , a monovalent aliphatic hydrocarbon group, a monovalent alicyclic hydrocarbon group, and a monovalent aromatic hydrocarbon group are mentioned, for example. As a monovalent aliphatic hydrocarbon group, a C1-C20 alkyl group, a C2-C20 alkenyl group, a C2-C20 alkynyl group is mentioned, for example. As monovalent alicyclic hydrocarbon, a C3-C20 cycloalkyl group is mentioned, for example. As a monovalent aromatic hydrocarbon group, a C6-C20 aryl group is mentioned, for example. Examples of the substituent for the monovalent hydrocarbon group in R ^p2 include a halogen atom, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, a halogenated hydrocarbon group, an alkyl group, an alkoxyl group, an amino group, a thiol group, and an organic sulfonyl group (RSO ₂ −). ), And the like.

ka is an integer of 1-3, Preferably it is an integer of 1 or 2. kb is an integer of 0-4, Preferably it is an integer of 0-3, More preferably, it is 0 or 1.

Particularly preferred examples of the structural unit (VI) include 4-hydroxystyrene, 4-tert-butoxystyrene, 4- (2-ethyl-2-propoxy) styrene, 4- (1-ethoxy) styrene, and a structural unit obtained by cleaving ethylenically unsaturated bonds in tert-butoxycarbonyl styrene, tert-butoxycarbonyl methylene styrene, and the like.

As a preferable monomer which produces | generates the structural unit (VI) derived from the said aromatic compound, For example, styrene, (alpha) -methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-methoxystyrene, 3 -Methoxystyrene, 4-methoxystyrene, 4- (2-t-butoxycarbonylethyloxy) styrene 2-hydroxystyrene, 3-hydroxystyrene, 4-hydroxystyrene, 2-hydroxy-α -Methylstyrene, 3-hydroxy-α-methylstyrene, 4-hydroxy-α-methylstyrene, 2-methyl-3-hydroxystyrene, 4-methyl-3-hydroxystyrene, 5-methyl-3- Hydroxystyrene, 2-methyl-4-hydroxystyrene, 3-methyl-4-hydroxystyrene, 3,4-dihydroxystyrene, 2,4,6-trihydroxystyrene, 4-t-butoxy Styrene, 4-t-butoxy-α-methylstyrene, 4- (2-ethyl-2-propoxy) styrene, 4- (2-ethyl-2-propoxy) -α-methylstyrene, 4- (1 -Ethoxyethoxy) styrene, 4- (1-ethoxyethoxy) -α-methylstyrene, (meth) acrylate , Benzyl (meth) acrylate, acenaphthylene, 5-hydroxyacenaphthylene, 1-vinylnaphthalene, 2-vinylnaphthalene, 2-hydroxy-6-vinylnaphthalene, 1-naphthyl (meth) acrylate, 2 Naphthyl (meth) acrylate, 1-naphthylmethyl (meth) acrylate, 1-anthryl (meth) acrylate, 2-anthryl (meth) acrylate, 9-anthryl (meth) acrylate, 9-anthryl methyl (meth) acrylate, 1-vinylpyrene, etc. are mentioned.

In the polymer [A], the content of the structural unit (VI) is preferably 5 mol% or more and 50 mol% or less, and 10 mol% or more and 30 mol% or less with respect to all the structural units constituting the [A] polymer. Is more preferable. In addition, the polymer [A] may have one or two or more structural units (VI).

<Method of synthesizing [A] polymer>

The polymer [A] can be synthesized by a conventional method such as radical polymerization. For example,

A method in which a solution containing a monomer and a radical initiator is added dropwise to a reaction solvent or a solution containing a monomer and polymerized;

A method in which a solution containing a monomer and a solution containing a radical initiator are added dropwise to a reaction solvent or a solution containing a monomer separately and subjected to a polymerization reaction;

A plurality of solutions containing each monomer and a solution containing a radical initiator can be separately added to a reaction solvent or a solution containing a monomer and synthesized by a method such as a polymerization reaction.

Although the polystyrene reduced weight average molecular weight (Mw) by gel permeation chromatography (GPC) of a polymer is not specifically limited, 1,000 or more and 500,000 or less are preferable, 2,000 or more and 400,000 or less are more preferable, 3,000 or more and 300,000 or less are Particularly preferred. Moreover, when Mw of a polymer [A] is less than 1,000, there exists a tendency for the heat resistance at the time of using a resist to fall. On the other hand, when Mw of a polymer [A] exceeds 500,000, there exists a tendency for the developability at the time of setting it as a resist to fall.

Moreover, ratio (Mw / Mn) of Mw with respect to polystyrene conversion number average molecular weight (Mn) by GPC of polymer [A] is 1 or more and 5 or less normally, 1 or more and 3 or less are preferable, 1 or more and 2 or less desirable. By setting Mw / Mn in such a range, the photoresist film is excellent in resolution performance.

Mw and Mn of the present specification, using a GPC column (Tosoh Corporation, two G2000HXL, one G3000HXL, one G4000HXL), under the analysis conditions of the flow rate 1.0mL / min, elution solvent tetrahydrofuran, column temperature 40 ℃, The value measured by GPC which makes monodisperse polystyrene the standard.

<[B] acid generator>

The acid generator (B) has at least one structure selected from the group consisting of a lactone structure, a cyclic carbonate structure, a sultone structure, and an alicyclic structure. Since the photoresist composition contains the [B] acid generator having such a bulky structure, the diffusion length of the acid can be made shorter, so that not only basic characteristics such as sensitivity and resolution, but also MEEF performance, DOF and LWR Also satisfies enough.

The acid generator (B) is preferably a structure represented by the following general formula (8).

In said formula (8), R <^11> is monovalent organic group containing a lactone structure, a cyclic carbonate structure, a sultone structure, or an alicyclic structure. R ¹² is a fluorinated methylene group or a fluorinated alkylene group having 2 to 10 carbon atoms. Provided that the carbon atom of the fluorinated alkylene group directly bonded to SO ₃ − has at least one fluorine atom. X ⁺ is an onium cation.

As an alicyclic structure in monovalent organic group containing the lactone structure, cyclic carbonate structure, sultone structure, or alicyclic structure represented by said R <^11> , it is, for example

Cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane, methylcyclohexane, ethylcyclohexane, cyclobutene, cyclopentene, cyclohexene, cycloheptene, cyclooctene, cyclodecene, cyclopentadiene Monocyclic alicyclic groups such as cyclohexadiene, cyclooctadiene, and cyclodecadiene;

Bicyclo [2.2.1] heptane, bicyclo [2.2.2] octane, tricyclo [5.2.1.0 ^2,6 ] decane, tricyclo [3.3.1.1 ^3,7 ] decane, tetracyclo [6.2.1.1 ^{3, 6.0 2,7]} dodecane, norbornane, adamantane, bicyclo [2.2.1] heptene, bicyclo [2.2.2] octene, tricyclo [5.2.1.0 ^2,6] decene, tricyclo And polycyclic alicyclic groups such as [3.3.1.1 ^3,7 ] decene and tetracyclo [6.2.1.1 ^{3,6 2,7} ] dodecene.

As a lactone structure, a sultone structure, or an alicyclic structure which said R <^11> has, the structure etc. which are represented by a following formula are mentioned, for example.

Of these, norbornane, adamantane, norbornanelactone ring and norbornanesultone ring are preferable. When the anion portion of the acid generator (B) has these bulky groups, diffusion of the acid can be further suppressed. As a result, the photoresist composition can form a resist pattern with better MEEF, DOF, and LWR.

The monovalent organic group containing the lactone structure, cyclic carbonate structure, sultone structure, or alicyclic structure which R <^11> represents may contain the said lactone structure, cyclic carbonate structure, sultone structure, or alicyclic structure 1 type, or 2 or more types. Moreover, as monovalent organic group containing the lactone structure, cyclic carbonate structure, sultone structure, or alicyclic structure which R <^11> represents, the group which consists only of the said lactone structure, cyclic carbonate structure, sultone structure, or alicyclic structure, the said lactone structure, cyclic Carbonate structure, a sultone structure or an alicyclic structure, and the group which combines 1 or more types chosen from the group which consists of a C1-C10 linear hydrocarbon group, an ether group, ester group, a carbonyl group, an imino group, and an amide group, etc. are mentioned. .

As a fluorinated methylene group and said C2-C10 fluorinated alkylene group which R <^12> represents, group represented by following General formula (9) is preferable.

In said Formula (9), k is an integer of 1-10. R ^f1 and R ^f2 are each independently a hydrogen atom, a fluorine atom or a fluorinated alkyl group having 1 to 4 carbon atoms. However, when k is 2 or more, some R <^f1> and R <^f2> may be same or different, respectively. Further, SO ₃ ^- R ^f1 or R ^f2 having a carbon atom directly bonded to a fluorine atom. * Is a site which binds to SO ₃ ⁻ .

As a C1-C4 fluorinated alkyl group represented by said R <^f1> and R <^f2> , for example, a fluorinated methyl group, a fluorinated ethyl group, a fluorinated n-propyl group, a fluorinated i-propyl group, a fluorinated n-butyl group, a fluorinated t-butyl group Etc. can be mentioned.

It is preferable that said k is an integer of 2-6.

As said R <^f1> and R <^f2> , a hydrogen atom and a fluorine atom are preferable.

R ¹¹ -R ¹² -SO ₃ in the above formula ⁽⁸⁾ As the anion represented by, for example to the like anion represented by the formula (8-1) to (8-24).

Among them, (8-5), (8-6) and (8-16) are preferable.

In said general formula (8), as an onium cation represented by X <^+> , a sulfonium cation, a thiophenium cation, an ammonium cation, a phosphonium cation, an iodonium cation, a pyridinium cation, etc. are mentioned, for example. Among them, sulfonium cation and thiophenium cation are preferable, and a cation represented by the following general formula (10) is more preferable. By using the onium cation of the acid generator (B) as a specific structure represented by the following general formula (10), diffusion of the generated acid can be further suppressed. As a result, the photoresist composition can form a resist pattern with better MEEF, DOF, and LWR.

In said Formula (10), R <^13> -R <^15> is respectively independently a hydrogen atom, a halogen atom, a hydroxyl group, a C1-C10 linear or branched alkyl group, a C3-C12 cycloalkyl group, and C1-C12 And an alkoxy group of 10, —SR ¹⁶ group, or a group having two or more heteroatoms. R ¹⁶ is an alkyl group or an aryl group. However, one part or all part of the hydrogen atom which the said alkyl group, a cycloalkyl group, an alkoxy group, and an aryl group have may be substituted.

As a C1-C10 linear or branched alkyl group represented by said R <^13> -R <^15> , for example, a methyl group, an ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl, n -Hexyl group, i-hexyl group, etc. are mentioned.

As a C3-C12 cycloalkyl group represented by said R <^13> -R <^15> , a cyclopropyl group, a cyclobutyl group, a cyclohexyl group, etc. are mentioned, for example.

As a C1-C10 alkoxy group represented by said R <^13> -R <^15> , a methoxy group, an ethoxy group, a propoxy group, butoxy group, a pentoxy group, etc. are mentioned, for example.

As the alkyl group represented by a group wherein R ^16, for example the R ¹³ to a group of a group like exemplified as the linear or branched alkyl group having 1 to 10 carbon atoms represented by R ^15, represented by the above R ¹³ to R ¹⁵ The group similar to the group illustrated as a C3-C12 cycloalkyl group, etc. are mentioned.

As an aryl group represented by said R <^16> group, a phenyl group, a naphthyl group, etc. are mentioned, for example.

As said hetero atom, an oxygen atom, a sulfur atom, a nitrogen atom, a halogen atom, etc. are mentioned, for example.

These [B] acid generators can also use 2 or more types together. As the usage-amount of the acid generator (B), 0.1 mass part or more and 25 mass parts or less are preferable with respect to 100 mass parts of [A] polymer from a viewpoint of ensuring the sensitivity and developability of the resist coating film formed with this photoresist composition. 1 mass part or more and 20 mass parts or less are more preferable.

<[C] acid diffusion control agent>

It is preferable that the photoresist composition further contains an [C] acid diffusion control agent. The acid diffusion control agent [C] controls the diffusion phenomenon in the resist coating film of the acid generated from the polymer [A] and the acid generator [B] by exposure to suppress undesirable chemical reaction in the unexposed part. It is to have an action. Therefore, the photoresist composition contains a [C] acid diffusion control agent in addition to the [A] polymer and the [B] acid generator to shorten the diffusion length of the acid and further suppress the diffusion of the acid. . As a result, the photoresist composition can form a resist pattern excellent in MEEF, DOF, and LWR. Moreover, as a containing form in the said composition of an acid diffusion control agent, the form of a free compound, the form inserted as a part of a polymer, or both forms may be sufficient as it.

[C] As the acid diffusion control agent, for example, an amine compound, an amide group-containing compound, a urea compound, a nitrogen-containing heterocyclic compound, a photodegradable base, and the like can be given.

As an amine compound, For example, Mono (cyclo) alkylamines; Di (cyclo) alkyl amines; Tri (cyclo) alkyl amines; Substituted alkyl anilines or derivatives thereof; Ethylenediamine, N, N, N ', N'-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylether, 4, 4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane , 2- (4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis (1- ( 4-aminophenyl) -1-methylethyl) benzene, 1,3-bis (1- (4-aminophenyl) -1-methylethyl) benzene, bis (2-dimethylaminoethyl) ether, bis (2-di Ethylaminoethyl) ether, 1- (2-hydroxyethyl) -2-imidazolidinone, 2-quinoxalinol, N, N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine , N, N, N ', N ", N" -pentamethyldiethylenetriamine, etc. are mentioned.

As the amide group-containing compound, for example, Nt-butoxycarbonyl group-containing amino compound, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetate Amide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone, N-acetyl-1-adamantylamine, isocyanuric tris (2-hydroxyethyl) and the like.

As the urea compound, for example, urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tri-n- Butyl thiourea etc. are mentioned. Among these, N-t-butoxycarbonyl group containing amino compound is preferable.

As a nitrogen-containing heterocyclic compound, For example, imidazole; Pyridines; Piperazines; Piperidine, piperidine, piperazine, pyrazole, pyridazine, quinoxaline, purine, pyrrolidine, piperidine, piperidine ethanol, 3-piperidino-1,2-propanediol, morpholine, 4- (4-morpholinyl) ethanol, 4-acetylmorpholine, 3- (N-morpholino) -1,2-propanediol, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2. 2] octane.

As a photodegradable base, the compound etc. which are represented by following General formula (11) are mentioned, for example.

In said general formula (11), R <^17> -R <^19> is respectively independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or a hydroxyl group. Y ^- is OH ^-, R ²⁰ COO ^-, or R ²⁰ -SO ₃ ^- a. R ²⁰ is an alkyl group, an aryl group or an aralkyl group. However, one part or all part of the hydrogen atom which the said alkyl group, an aryl group, and an aralkyl group have may be substituted. In addition, Y ^- is R ²⁰ -SO ₃ ^- in the case, SO ₃ ^- is not the case that a direct bond with the carbon atom having a fluorine atom.

As a halogen atom which said R <^17> -R <^19> represents, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned, for example.

As an alkyl group which said R <^17> -R <^19> represents, For example, linear alkyl groups, such as a methyl group, an ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group;

Cycloalkyl groups, such as a cyclopentyl group, a cyclohexyl group, and a norbornyl group, etc. are mentioned.

As an alkoxy group which said R <^17> -R <^19> represents, a methoxy group, an ethoxy group, a propoxy group, butoxy group etc. are mentioned, for example.

As an alkyl group which said R <^20> represents, the group similar to the group illustrated as an alkyl group which said R <^17> -R <^19> represents, for example is mentioned.

Among these, as the [C] acid diffusion control agent, a photo-degradable base is preferable, and the compound represented by the following general formulas (C-1) to (C-5) is more preferable.

Among these, the compounds represented by the formulas (C-1) and (C-2) are more preferred. (C) By using the said preferable compound as an acid diffusion control agent, it can function more highly and can further suppress acid diffusion. As a result, the photoresist composition is better in MEEF, DOF and LWR.

These [C] acid diffusion control agents may be used independently and may use 2 or more types together. As the usage-amount of the [C] acid diffusion control agent in this photoresist composition, 0.1 mass part or more and 25 mass parts or less are preferable with respect to 100 mass parts of [A] polymers, and 1 mass part or more and 20 mass parts or less are more preferable. Do. If the amount of the acid diffusion control agent (C) is less than 0.1 part by mass, there is a problem that the reduction of MEEF is not achieved, and thus the effect of the present invention may not be fully exhibited. On the other hand, when it exceeds 15 mass parts, shape deterioration by the sensitivity fall of the said photoresist composition and the resist transmittance fall may be observed.

<Solvent>

The photoresist composition usually contains a solvent. Examples of the solvent include alcohol solvents, ketone solvents, amide solvents, ether solvents, ester solvents, mixed solvents thereof, and the like. These solvents may use 2 or more types together.

As the alcoholic solvent, for example,

Propanol, iso-butanol, sec-butanol, tert-butanol, n-pentanol, iso-pentanol, Butanol, 2-ethylhexanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol , sec-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, secundecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, Monoalcohol solvents such as furyl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol and diacetone alcohol;

Propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4- Polyhydric alcohol solvents such as 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol and tripropylene glycol;

Ethylene glycol monoethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol mono Methyl ethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene Glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and dipropylene glycol monopropyl ether; and the like.

As a ketone solvent, acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-iso-butyl ketone, methyl-n-pentyl ketone, ethyl-n- Butyl ketone, methyl-n-hexyl ketone, di-iso-butyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone, 2,4-pentanedione, aceto Ketone solvents, such as acetone, diacetone alcohol, and acetophenone, are mentioned.

Examples of the amide solvent include N, N'-dimethylimidazolidinone, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide , N, N-dimethylacetamide, N-methylpropionamide, N-methylpyrrolidone and the like.

As an ether solvent, diethyl ether, dipropyl ether, dibutyl ether, diphenyl ether, methoxybenzene, etc. are mentioned, for example.

Examples of the ester solvent include diethyl carbonate, propylene carbonate, methyl acetate, ethyl acetate, γ-valerolactone, n-propyl acetate, iso-propyl acetate, n-butyl acetate, iso-butyl acetate and sec-acetic acid Butyl, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-acetic acid Nonyl, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether To propylene glycol monomethyl ether and propylene glycol monoethyl acetate Le, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, diacetic acid glycol, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, Iso-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate, diethyl phthalate, and the like.

As another solvent, for example

aliphatic alcohols such as n-pentane, iso-pentane, n-hexane, isohexane, n-heptane, isoheptane, 2,2,4-trimethylpentane, n-octane, iso-octane, cyclohexane and methylcyclohexane Hydrocarbon solvents;

Benzene, toluene, xylene, mesitylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propylbenzene, isopropylbenzene, diethylbenzene, isobutylbenzene, triethylbenzene, di- An aromatic hydrocarbon solvent such as amylnaphthalene;

And halogen-containing solvents such as dichloromethane, chloroform, freon, chlorobenzene and dichlorobenzene.

Among these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether, ethyl lactate, and cyclohexanone are preferable.

<Other optional components>

The photoresist composition may contain other optional components such as fluorine atom-containing polymers, acid generators other than the [B] acid generator, alicyclic skeletal compounds, surfactants, sensitizers, and the like without affecting the effects of the present invention. It may contain. Hereinafter, these arbitrary components are demonstrated in detail. These other arbitrary components can be used individually or in mixture of 2 or more types, respectively. In addition, the compounding quantity of another arbitrary component can be suitably determined according to the objective.

[Fluorine atom-containing polymer]

The photoresist composition may contain a polymer having a higher fluorine atom content than the polymer [A]. When the photoresist composition contains a fluorine atom-containing polymer, when the resist film is formed, the oil-repellent characteristics of the fluorine atom-containing polymer in the film tend to be localized near the surface of the resist film, so that the liquid immersion exposure is performed. Elution of an acid generator, an acid diffusion control agent, or the like into the immersion medium can be suppressed. In addition, by the water repellent characteristic of the fluorine atom-containing polymer, the advancing contact angle between the resist film and the liquid immersion medium can be controlled to a desired range, and generation of bubble defects can be suppressed. In addition, the receding contact angle between the resist film and the liquid immersion medium is increased, and scanning exposure at high speed is possible without water droplets remaining. Thus, the resist coating film suitable for the immersion exposure method can be formed by containing a fluorine atom containing polymer.

Although it does not specifically limit as long as it has a fluorine atom as said fluorine-containing polymer, It is essential that a fluorine atom content rate (mass%) is higher than a polymer [A]. When the content of fluorine atoms is higher than that of the polymer (A), the degree of localization described above is higher, and the properties such as water repellency and elution inhibiting property of the resulting resist coating film are improved.

The fluorine atom containing polymer in this invention is formed by superposing | polymerizing 1 or more types of monomers which contain a fluorine atom in a structure.

As a monomer which provides the polymer which contains a fluorine atom in a structure, the monomer which contains a fluorine atom in a principal chain, the monomer which contains a fluorine atom in a side chain, and the monomer which contains a fluorine atom in a main chain and a side chain are mentioned.

As a monomer which provides the polymer containing a fluorine atom in a principal chain, it is an (alpha)-fluoroacrylate compound, the (alpha)-trifluoromethylacrylate compound, the (beta)-fluoroacrylate compound, (beta)-trifluoromethyl acryl, for example. The compound in which the hydrogen of the rate compound, the (alpha), (beta)-fluoroacrylate compound, the (alpha), (beta)-trifluoromethylacrylate compound, and the 1 or more vinyl site was substituted by fluorine or a trifluoromethyl group, etc. are mentioned.

As a monomer which provides the polymer which contains a fluorine atom in a side chain, the side chain of alicyclic olefin compound like a norbornene is a fluorine or a fluoroalkyl group or its derivative (s), a fluoroalkyl group of acrylic acid or methacrylic acid, or its derivative (s), for example. The ester compound and the side chain (site | part which does not contain a double bond) of 1 or more types of olefin are a fluorine atom, a fluoroalkyl group, its derivative, etc. are mentioned.

As a monomer which provides the polymer which contains a fluorine atom in a main chain and a side chain, it is alpha-fluoroacrylic acid, (beta) -fluoroacrylic acid, (alpha), (beta) -fluoroacrylic acid, (alpha) -trifluoromethylacrylic acid, (beta) -tri Ester compounds of fluoroalkyl groups such as fluoromethylacrylic acid and α, β-trifluoromethylacrylic acid or derivatives thereof, and the side chains of compounds in which hydrogen of at least one vinyl moiety is substituted with a fluorine atom or a trifluoromethyl group. Substituted by an atom or a fluoroalkyl group or a derivative thereof, hydrogen bonded to a double bond of one or more alicyclic olefin compounds by a fluorine atom or a trifluoromethyl group, and the side chain is a fluoroalkyl group or a derivative thereof And the like can be mentioned. In addition, this alicyclic olefin compound shows the compound whose one part of ring is a double bond.

As a structural unit which a fluorine atom containing polymer has, the structural unit represented by the following general formula (henceforth also called a "structural unit (VII)") is mentioned.

In said formula, R <^21> is hydrogen, a methyl group, or a trifluoromethyl group. Z is a linking group. R ²² is a linear or branched alkyl group having 1 to 6 carbon atoms containing at least one or more fluorine atoms, or a monovalent alicyclic group having 4 to 20 carbon atoms or a derivative thereof.

As a coupling group which Z represents, a single bond, an oxygen atom, a sulfur atom, a carbonyloxy group, an oxycarbonyl group, an amide group, a sulfonylamide group, a urethane group, etc. are mentioned, for example.

As a monomer which provides a structural unit (VII), for example, 2- [1- (ethoxycarbonyl) -1,1-difluorobutyl] (meth) acrylic acid ester and trifluoromethyl (meth) acrylic acid ester , 2,2,2-trifluoroethyl (meth) acrylic acid ester, perfluoroethyl (meth) acrylic acid ester, perfluoro n-propyl (meth) acrylic acid ester, perfluoro i-propyl (meth) acrylic acid ester , Perfluoro n-butyl (meth) acrylic acid ester, perfluoro i-butyl (meth) acrylic acid ester, perfluoro t-butyl (meth) acrylic acid ester, 2- (1,1,1,3,3, 3-hexafluoropropyl) (meth) acrylic acid ester, 1- (2,2,3,3,4,4,5,5-octafluoropentyl) (meth) acrylic acid ester, perfluorocyclohexylmethyl ( Meth) acrylic acid ester, 1- (2,2,3,3,3-pentafluoropropyl) (meth) acrylic acid ester, 1- (3,3,4,4,5,5,6,6,7, 7,8,8,9,9,10,10,10-heptadecafluorode ) (Meth) acrylate, hexyl) (meth methyl -3,3,4,4,5,6,6,6- octafluoro-l (5-trifluoromethyl) acrylic acid ester and the like.

The fluorine atom-containing polymer may contain two or more kinds of structural units (VII). The content rate of the structural unit (VII) is usually 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% when the total structural unit in the fluorine atom-containing polymer is 100 mol%. That's it. If the content rate of this structural unit (VII) is less than 5 mol%, there exists a possibility that a receding contact angle of 70 degree | times or more cannot be achieved, and elution of an acid generator etc. from a resist coating film may not be suppressed.

In addition to the structural unit (VII), the fluorine atom-containing polymer may be, for example, a structural unit having an acid dissociable group, a lactone skeleton, a hydroxyl group, a carboxyl, or the like by light from reflection from a substrate to control the dissolution rate in a developer. In order to suppress scattering, one or more "other structural units", such as structural units derived from an aromatic compound, can be contained.

As another structural unit which has the said acid dissociable group, the structural unit similar to the structural unit illustrated by the said structural unit (II) in [A] polymer can be applied. As another structural unit containing the said lactone skeleton, the structural unit similar to the structural unit illustrated by the said structural unit (IV) in a polymer [A] can be applied. As another structural unit containing the said hydroxyl group, the structural unit similar to the structural unit illustrated by the said structural unit (V) in a polymer [A] is applicable. As a structural unit derived from the said aromatic compound, the structural unit similar to the structural unit illustrated by the said structural unit (VI) in a polymer [A] can be applied.

As content rate of another structural unit, when the total structural unit in a fluorine atom containing polymer is 100 mol%, it is 80 mol% or less normally, Preferably it is 75 mol% or less, More preferably, it is 70 mol% or less. .

As Mw of a fluorine atom containing polymer, 1,000 or more and 50,000 or less are preferable, 1,000 or more and 30,000 or less are more preferable, 1,000 or more and 10,000 or less are especially preferable. When the Mw of the fluorine atom-containing polymer is less than 1,000, a sufficient forward contact angle cannot be obtained. On the other hand, when the Mw exceeds 50,000, the developability in the resist tends to be lowered. As ratio (Mw / Mn) of Mw and Mn of a fluorine atom containing polymer, they are 1 or more and 3 or less normally, Preferably they are 1 or more and 2 or less.

As a content rate of the fluorine atom containing polymer in the said photoresist composition, 0 mass part or more and 50 mass parts or less are preferable with respect to 100 mass parts of [A] polymers, 0 mass part or more and 20 mass parts or less are more preferable. And 0.5 mass part or more and 10 mass parts or less are especially preferable, and 1 mass part or more and 8 mass parts or less are the most preferable. By making the content rate of the said fluorine atom containing polymer in the said photoresist composition into the said range, the water repellency and elution inhibitory property of the surface of the resist coating film obtained can be improved more.

[Synthesis method of fluorine atom-containing polymer]

The said fluorine atom containing polymer can synthesize | combine the monomer corresponding to each predetermined structural unit, for example by superposing | polymerizing in a suitable solvent using a radical polymerization initiator.

As a solvent used for the said superposition | polymerization, the solvent similar to what was illustrated by the synthesis method of the [A] polymer, for example is mentioned.

As reaction temperature in the said superposition | polymerization, it is 40 degreeC or more and about 150 degrees C or less normally, and 50 degreeC or more and 120 degrees C or less are preferable. As reaction time, it is about 1 hour or more and about 48 hours or less normally, and 1 hour or more and 24 hours or less are preferable.

[[B] Acid Generators Other Than Acid Generators]

The photoresist composition may contain an acid generator other than the [B] acid generator within a range that does not impair the effects of the present invention. Examples of such acid generators include onium salt compounds, sulfonimide compounds, halogen-containing compounds, diazoketone compounds and the like other than the [B] acid generator.

Examples of the onium salt compound include sulfonium salts (including tetrahydrothiophenium salts), iodonium salts, phosphonium salts, diazonium salts, pyridinium salts, and the like.

Examples of the sulfonium salt include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, and 4-cyclohexyl Phenyldiphenylsulfoniumtrifluoromethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexylphenyldiphenylsulfonium perfluoro-n-octanesulfonate, 4-methanesulfonylphenyldiphenylsulfoniumtrifluoromethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium perfluoro -n-octane sulfonate etc. are mentioned. Among them, triphenylsulfonium trifluoromethanesulfonate and triphenylsulfonium nonafluoro-n-butanesulfonate are preferable.

As the tetrahydrothiophenium salt, for example, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumtrifluoromethanesulfonate and 1- (4-n-butoxynaphthalene-1- 1) tetrahydrothiopheniumnonafluoro-n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- ( 6-n-butoxynaphthalen-2-yl) tetrahydrothiopheniumtrifluoromethanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiopheniumnonafluoro-n- Butanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetra Hydrothiopheniumtrifluoromethanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (3,5-dimethyl- 4-hydroxyphenyl) tetrahydrothiophenium purple And the like Oro -n- octane sulfonate. Among these tetrahydrothiophenium salts, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- -Tetrahydrothiophenium perfluoro-n-octanesulfonate and 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate are preferable .

Examples of iodonium salts include diphenyl iodonium trifluoromethanesulfonate, diphenyl iodonium nonafluoro-n-butanesulfonate, diphenyl iodonium perfluoro-n-octane sulfonate, Bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) Iodonium perfluoro-n-octanesulfonate, etc. may be mentioned. Among these iodonium salts, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate is preferable.

Examples of the sulfonimide compound include N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (nonafluoro- (Perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- -2,3-dicarboxyimide, N- (2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy) bicyclo [2.2. 1] hept-5-ene-2,3-dicarboxyimide. Among these sulfonimide compounds, N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide is preferable.

Acid generators other than these [B] acid generators may be used independently and may use 2 or more types together.

Alicyclic Skeleton Compound

An alicyclic skeleton compound is a component which shows the effect | action which further improves dry etching resistance, a pattern shape, adhesiveness with a board | substrate, etc. As an alicyclic skeleton compound, For example, adamantane derivatives, such as 1-adamantanecarboxylic acid, 2-adamantanone, and 1-adamantanecarboxylic acid t-butyl; Deoxycholic acid esters such as deoxycholic acid t-butyl, deoxycholic acid t-butoxycarbonylmethyl and deoxycholic acid 2-ethoxyethyl; Litocholic acid ester, such as t-butyl lithocholate, t-butoxycarbonylmethyl lithocholic acid, and 2-ethoxyethyl lithocholic acid; 3- [2-hydroxy-2,2-bis (trifluoromethyl) ethyl] tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecane, 2-hydroxy-9-methoxycarbonyl -5-oxo-4-oxa-tricyclo [4.2.1.0 ^3,7 ] nonane etc. are mentioned.

[Surfactants]

Surfactant is a component which shows the effect | action which improves applicability, striation, developability, etc.

As surfactant, For example, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octylphenyl ether, polyoxyethylene n-nonylphenyl ether, polyethylene glycol dilau In addition to nonionic surfactants such as latex and polyethylene glycol distearate, KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 75, and Polyflow No. 95 (above, Kyoisha Chemical Co., Ltd.) ), F-Top EF301, F-Top EF303, F-Top EF352 (above, manufactured by Tochem Products), Mega Face F171, Mega Face F173 (above, manufactured by Dainippon Ink & Chemicals Co., Ltd.), Fluorade FC430, Fluoride FC431 (above, Sumitomo 3M), Asahigard AG710, Suplon S-382, Suplon SC-101, Suplon SC-102, Suplon SC-103, Suplon SC-104, Suplon SC-105, Suplon SC- 106 (more than Asahi glass product ), And the like.

[Sensitizer]

A sensitizer exhibits the effect of absorbing the energy of radiation, transferring the energy to the [B] acid generator, and thereby increasing the amount of acid generated, thereby improving the "apparent sensitivity" of the photoresist composition. . Examples of the sensitizer include carbazoles, acetophenones, benzophenones, naphthalenes, phenols, nonacetyls, eosin, rose bengals, pyrenes, anthracenes, phenothiazines and the like.

&Lt; Method for producing photoresist composition >

The photoresist composition can be produced, for example, by mixing the [A] polymer, the [B] acid generator, the [C] acid diffusion control agent and other optional components in a predetermined ratio in the solvent.

The solvent is not particularly limited as long as the polymer [A], the acid generator [B], the acid diffusion control agent [C] and other optional components can be dissolved or dispersed. In general, the photoresist composition is dissolved in a solvent such that the total solid concentration is 1% by mass or more and 30% by mass or less, preferably 1.5% by mass or more and 25% by mass or less, for example, a pore diameter of 0.2. It is manufactured by filtration with a filter of about 탆.

<Formation method of resist pattern>

Using the photoresist composition of this invention, a resist pattern can be formed, for example by the following process.

(1) forming a coating film of the photoresist composition on a substrate (hereinafter also referred to as "step (1)");

(2) irradiating at least a part of the coating film with radiation (hereinafter also referred to as "step (2)"), and

(3) It has a process (henceforth a "process (3)") which develops the coating film irradiated with the said radiation. Hereinafter, each step will be described in detail.

By using this photoresist composition, the resist pattern excellent in MEEF, DOF, and LWR can be formed. Therefore, even with radiation such as KrF excimer laser, ArF excimer laser, EUV, and the like, fine patterns can be stably formed from the photoresist composition with high accuracy, and can be preferably used for the manufacture of semiconductor devices expected to be further refined in the future. .

[Step (1)]

In this step, the photoresist composition or the solution of the photoresist composition obtained by dissolving it in a solvent is coated with a silicon wafer, silicon dioxide, an antireflection film, or the like by applying means such as rotation coating, cast coating or roll coating. The substrate is coated so as to have a predetermined film thickness, and in some cases, prebaking (PB) is performed at a temperature of 70 ° C. or more and 160 ° C. or less to volatilize the solvent in the coating film to form a resist film.

[Step (2)]

In this step, the resist film formed in step (1) is irradiated with radiation (in some cases, through an immersion medium such as water) and exposed. In addition, radiation is irradiated through the mask which has a predetermined pattern at this time. As radiation, it selects suitably from visible light, an ultraviolet-ray, an ultraviolet-ray, X-ray, a charged particle beam, EUV etc. according to the line width of the target pattern, and irradiates. Among these, far ultraviolet rays represented by ArF excimer laser (wavelength 193 nm) and KrF excimer laser (wavelength 248 nm) are preferable, and even a light source capable of forming a finer pattern such as EUV (extreme ultraviolet light, wavelength 13.5 nm) It can be used preferably. Subsequently, it is preferable to perform post-exposure baking (PEB). By this PEB, it becomes possible to advance the separation of the acid dissociable group of the polymer [A] smoothly. Although heating conditions of PEB can be suitably selected according to the compounding composition of a photoresist composition, they are about 50 degreeC or more and 180 degrees C or less normally.

[Step (3)]

This step forms a resist pattern by developing the exposed resist film with a developer. After development, washing with water and drying are common. As a developing solution, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, ammonia water, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine , Ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene, 1,5-diazabicyclo- [4.3.0] Alkali aqueous solution which melt | dissolved at least 1 sort (s) of alkaline compounds, such as -5-nonene, is preferable.

In addition, when performing immersion exposure, in order to protect the direct contact of an immersion liquid and a resist film, you may form the immersion liquid insoluble protective film on a resist film before a process (2). As the immersion protective film, a solvent peeling type protective film (for example, see Japanese Patent Laid-Open No. 2006-227632, etc.) peeled off with a solvent before the step (3), a developer peeling type to be peeled off simultaneously with the development of the step (3). You may use any of a protective film (for example, international publication 2005-069076, international publication 2006-035790, etc.).

<Examples>

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

Mw and Mn of the polymer were measured under the following conditions using a GPC column (Tosoh Corporation, two G2000HXL, one G3000HXL, one G4000HXL).

Column temperature: 40 DEG C

Elution solvent: dimethylformamide

(LiBr 0.3% (mass equivalent), H ₃ PO ₄ 0.1% (mass equivalent) mixed solution)

Flow rate: 1.0 mL / min

Sample concentration: 0.2% by mass

Sample injection amount: 100 μL

Detector: differential refractometer

Standard material: monodisperse polystyrene

¹³ C-NMR analysis was measured using a nuclear magnetic resonance device (Nihon Denshi Co., JNM-EX270).

As for the residual amount of the low molecular-weight component derived from a monomer, using the GE Science Intersil ODS-25micrometer column (4.6 mm x 250 mm), the flow rate 1.0 milliliter / min, the elution solvent acrylonitrile / 0.1% phosphoric acid aqueous solution analysis conditions As measured by high performance liquid chromatography (HPLC).

<Synthesis of [A] Polymer>

The monomer used for the synthesis | combination of the [A] polymer and the [D] fluorine atom containing polymer mentioned later is shown below.

[Synthesis Example 1]

10.46 g (40 mol%) of compound (M-1), 3.5 g (10 mol%) of compound (M-2), 1.83 g (2 mol%) of compound (M-3), and 14.22 g of compound (M-4) (48 mol%) was dissolved in 60 g of methyl ethyl ketone, and 2.2 g of AIBN was added to prepare a monomer solution. A 500 mL three-necked flask containing 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, heated to 80 ° C. while stirring, and the prepared monomer solution was added dropwise over 3 hours with a dropping funnel. The initiation of the dropwise addition was regarded as the start time of the polymerization reaction, and the polymerization reaction was carried out for 6 hours. After completion of the polymerization reaction, the polymerization solution was cooled with water to 30 캜 or lower. The polymerization solution cooled in 600 g of isopropanol / hexane mixed liquids (50 mass%: 50 mass%) was thrown in, and the white powder which precipitated was separated by filtration. The white powder separated by filtration was washed twice with slurry in 120 g of isopropanol, and then filtered and dried at 50 ° C. for 17 hours to obtain a white powdery polymer (A-1) (18.6 g, yield 62.0%). Mw of the obtained polymer (A-1) was 4,374 and Mw / Mn was 1.56. The residual amount of the low molecular weight component was 1.0%. In addition, as a result of ¹³ C-NMR analysis, the structural unit derived from the compound (M-1): The structural unit derived from the compound (M-2): The structural unit derived from the compound (M-3): The compound (M-4) derived The content rate of the structural unit of was 42.1: 8.2: 2.2: 47.5 (mol%).

[Synthesis Examples 2 to 11]

Except having mix | blended the predetermined amount of the monomer of Table 1, it carried out similarly to the synthesis example 1, and obtained polymer (A-2)-(A-10) and (a-1). In addition, the content rate of the structural unit derived from each monomer in each polymer in Mw, Mw / Mn, the yield (%) of the obtained polymer, the residual amount (%) of a low molecular weight component, and each polymer is shown in Table 1 together.

<Synthesis of [D] fluorine atom-containing polymer>

[Synthesis Example 12]

35.83 g (70 mol%) of monomers (M-11) and 14.17 g (30 mol%) of monomers (M-12) are dissolved in 50 g of 2-butanone, and again dimethyl 2,2'-azobis (2) as an initiator. -Methyl propionate) 5.17 g (8 mol%) was added to prepare a monomer solution. Next, 50 g of 2-butanone was put into a 500 ml three-necked flask equipped with a thermometer and a dropping funnel and purged with nitrogen for 30 minutes. After purging with nitrogen, the flask was heated to 80 ° C. with stirring with a magnetic stir bar. The monomer solution prepared previously was dripped over 3 hours using the dropping funnel. The start of dropping was regarded as polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization solution was cooled to 30 ° C or lower by water cooling. After cooling, the reaction solution, 150 g of hexane, 600 g of methanol, and 30 g of water were poured into a separating funnel, followed by stirring, and then allowed to stand. The mixed solution was separated into two layers, and the lower layer (resin solution) was separated after standing for 3 hours. The resin solution fractionated using the evaporator was solvent-substituted by the propylene glycol monomethyl ether acetate solution. 159.2 g of propylene glycol monomethyl ether acetate solution of the copolymer was obtained. Solid content concentration was calculated | required using the hotplate, and the copolymer concentration was 20.1% and the yield was 64%. This copolymer was used as resin (A-3). This copolymer had a Mw of 6,900 and a Mw / Mn of 1.34. ^As a result of ¹³ C-NMR analysis, the copolymer (D-1) having a content ratio of the repeating unit derived from the compound (M-5): the repeating unit derived from the compound (M-7) was 70.5: 29.5 (mol%). .

&Lt; Preparation of photoresist composition >

It shows below about the [B] acid generator, [C] acid diffusion control agent, and solvent which were used for manufacture of a photoresist composition.

<[B] acid generator>

B-1 to B-5: a compound represented by the following formula

B-6: triphenylsulfonium nona plate

<[C] acid diffusion control agent>

C-1 to C-3: a compound represented by the following formula

<Solvent>

E-1: Propylene glycol monomethyl ether acetate

E-2: cyclohexanone

E-3: γ-butyrolactone

Example 1

100 parts by mass of the polymer (A-1), 11 parts by mass of the acid generator (B-1), 5.5 parts by mass of the acid diffusion control agent (C-1), 3 parts by mass of the polymer (D-1), the solvent (E-1 ), 2,220 mass parts, (E-2) 950 mass parts, and (E-3) 30 mass parts were mixed, and the obtained mixed solution was filtered with the filter of 0.2 micrometer of pore diameters, and the photoresist composition was produced.

[Examples 2 to 15 and Comparative Examples 1 to 3]

The photoresist composition was manufactured like Example 1 except having used each component of the kind and quantity shown in Table 2.

<Evaluation by ArF excimer laser>

The following evaluation results are combined with Table 2 and shown.

[Evaluation of Sensitivity]

A film having a thickness of 75 nm was formed on the 12-inch silicon wafer on which the lower layer anti-reflection film (ARC66, manufactured by Nissan Chemical Industries, Ltd.) was formed by a photoresist composition, and soft baking (SB) was performed at 120 ° C. for 60 seconds. Subsequently, this film was formed using an ArF excimer laser immersion exposure apparatus ("NSR S610C", manufactured by Nikon Corporation) under a condition of NA = 1.3, ratio = 0.800, Annular, and a 46 nm line 92 nm pitch. It exposed through the mask pattern for pattern formation. After exposure, each photoresist composition was post-baked (PEB) at 100 ° C. for 60 seconds. Then, it developed by 2.38 mass% tetramethylammonium hydroxide aqueous solution, washed with water, dried, and formed the positive resist pattern. At this time, the exposure amount which the part exposed through the pattern formation mask pattern of 46 nm line 92 nm pitch forms a 46-nm line width was made into optimal exposure amount (Eop). This optimum exposure amount was made into the sensitivity (mJ / cm <2>). In addition, the scanning electron microscope (the Hitachi High-Technologies company, CG4000) was used for the length measurement. When the sensitivity was 50 (mJ / cm 2) or less, the evaluation was good.

[MEEF]

Using the Eop, the target size of the line width in the 92 nm pitch is 43 nm line, 44 nm line, 45 nm line, 46 nm line, 47 nm line, 48 nm line, and 49 nm line, respectively. An LS pattern having a pitch of 92 nm was formed, and the line width formed on the resist film was measured by length measurement SEM (Hitachi Corp., CG4000). At this time, the slope of the straight line when the target size (nm) was plotted on the horizontal axis and the line width (nm) formed on the resist film using the respective mask patterns on the vertical axis was calculated as MEEF. The closer the value is to 1, the better the mask reproducibility, and the lower the value of the MEEF, the lower the mask manufacturing cost. A result is combined with Table 2 and shown.

[Linewidth roughness (LWR)]

The line of 46 nm in line width formed from said Eop was observed from the upper part of a pattern using length measurement SEM "CG4000" of Hitachi company, and the line width was measured in arbitrary 10 points. The 3-sigma value (deviation) of the measured value of the line width was defined as LWR (nm). When the value of this LWR was 6.2 nm or less, it evaluated that the formed pattern shape was favorable.

Depth of Focus (DOF)

As the optimum exposure dose (Eop) in the evaluation of the sensitivity, the blurring width of the focus when the pattern size resolved at 45 nm line and 150 nm pitch is within ± 10% of the design dimension of the mask, DOF (nm). It was set as.

As shown in Table 2, it was found that the photoresist composition of the present invention was excellent in the overall lithography performance of sensitivity, MEEF, DOF, and LWR.

<Evaluation by electron beam>

[Examples 18 and 19 and Comparative Example 4]

The following evaluation was performed on the conditions shown in Table 2 using each photoresist composition used in Examples 1-2 and Comparative Example 1.

[Evaluation of Photoresist Composition]

After spin-coating each composition solution on a silicon wafer in "Clean Track ACT-8" manufactured by Tokyo Electron, PB (heating treatment) was performed under the conditions shown in Table 3 to form a resist film having a thickness of 60 nm. Formed. Then, the electron beam was irradiated to the resist film using the simple electron beam drawing apparatus (The Hitachi Seisakusho make, model "HL800D", the output 50 KeV, the current density 5.0 amps / cm <2>). After irradiation of the electron beam, PEB was performed on the conditions shown in Table 3. Then, using a 2.38% tetramethylammonium hydroxide aqueous solution, it developed by the puddle method at 23 degreeC for 1 minute, and then washed with pure water, dried, and formed the resist pattern. The following items were evaluated about the resist formed in this way. The evaluation results are written together in Table 3.

(1) Sensitivity (L / S)

A pattern (so-called line-and-space pattern (1L1S)) including a line portion having a line width of 150 nm and a space portion (that is, a groove) having a spacing of 150 nm formed by adjacent line portions (one to one) The exposure amount formed by the line width was made into the optimum exposure amount, and the sensitivity was evaluated by this optimum exposure amount, and FIG. 1 is a top view which shows typically the shape of a line and space pattern. It is sectional drawing which shows typically the shape of an end space pattern, but the unevenness | corrugation shown in FIG. 1 and FIG. 2 is exaggerated rather than actual.

(2) Nano Edge Roughness

The line pattern of the line-and-space pattern (1L1S) of 150 nm of design line | wire width was observed with the scanning electron microscope for semiconductors (high resolution FEB length measuring apparatus, brand name "S-9220", the Hitachi Seisakusho company make). As shown in Figs. 1 and 2, the observed shape is at the point where the unevenness formed along the transverse side surface 2a of the line portion 2 of the resist film formed on the silicon wafer 1 is most remarkable. The nanoedge roughness was evaluated by measuring the difference "(DELTA) CD" of line width and 150 nm of design line widths by CD-SEM ("S-9220" by Hitachi High-Technologies Corporation).

(3) Resolution (L / S)

About the line and space pattern 1L1S, the minimum line width (nm) of the line pattern resolved by the optimal exposure amount was made into the resolution.

According to Tables 2 and 3, the photoresist compositions of Examples 18 to 19 of the present invention are more sensitive to electron beams or extreme ultraviolet rays than the photoresist compositions of Comparative Example 4, and have low roughness and excellent resolution. It was confirmed that a chemically amplified positive resist film capable of forming fine patterns stably with high precision could be formed.

The photoresist composition of this invention is used suitably in formation of the resist pattern in the lithography process of various electronic devices, such as a semiconductor device and a liquid crystal device.

1: substrate
2: resist pattern
2a: transverse side of resist pattern

Claims (11)

[A] a polymer having an acid generator, and
[B] an acid generator having at least one structure selected from the group consisting of a lactone structure, a cyclic carbonate structure, a sultone structure, and an alicyclic structure
Lt; / RTI &gt; The photoresist composition of claim 1, wherein the acid generator [B] has at least one structure selected from the group consisting of lactone structures and sultone structures. The at least one structural unit according to claim 1, wherein the polymer [A] is selected from the group consisting of structural units (I) represented by the following general formula (1) and structural units (II) represented by the following general formula (2). Photoresist composition comprising a.

(In formula (1), R ^p1 is a hydrogen atom, a fluorine atom, a trifluoromethyl group or an alkyl group having 1 to 3 carbon atoms, R ^p2 is a divalent organic group, and a plurality of Rf are each independently a hydrogen atom or a fluorine atom) Or a fluorinated alkyl group having 1 to 3 carbon atoms, n is an integer of 0 to 6, M ⁺ is an onium cation,
In formula (2), R ^p3 is a hydrogen atom, a fluorine atom, a trifluoromethyl group or an alkyl group having 1 to 3 carbon atoms, R ^p4 , R ^p5 and R ^p6 are each independently an organic group having 1 to 10 carbon atoms, m Is an integer of 0 to 3, when m is 2 or more, a plurality of R ^p4 may be the same or different, and A is a single bond, an alkanediyl group having 1 to 10 carbon atoms, an alkyleneoxy group having 2 to 10 carbon atoms, or Arylene group having 6 to 10 carbon atoms, X ⁻ is a sulfonate anion, a carboxylate anion or an amide anion) 4. The photoresist composition of claim 3, wherein the polymer [A] comprises a structural unit (I) represented by the formula (1), and M ⁺ of the formula (1) is represented by the formula (3) .

(In formula (3), R ^p7 to R ^p9 are each independently a hydrocarbon group having 1 to 30 carbon atoms, provided that R ^p7 and R ^p8 are bonded to each other to form a cyclic structure with the sulfur atom to which they are bonded. Some or all of the hydrogen atoms of the hydrocarbon group may be substituted) The photoresist composition according to claim 3, wherein the polymer [A] comprises a structural unit (I) represented by the above formula (1), and M ⁺ of the above formula (1) is represented by the following formula (4) .

(In formula (4), R ^p10 to R ^p12 are each independently a hydroxyl group, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a group having a -SR ^x group or a plurality of hetero atoms, and R ^x is an alkyl group or an aryl group. However, some or all of the hydrogen atoms of the alkyl group, cycloalkyl group, alkoxy group and aryl group may be substituted, a is an integer of 1 to 5, b and c are each independently an integer of 0 to 5) The photoresist composition of claim 5, wherein at least one of R ^p10 to R ^p12 is a group represented by the following general formula (4-1) or the following general formula (4-2).

(In Formulas (4-1) and (4-2), R ^x is the same as that of Formula (4).) 4. The photoresist composition of claim 3, wherein the polymer [A] comprises a structural unit (II) represented by the formula (2), wherein X ^- in the formula (2) is represented by the following formula (5). .

(In formula (5), R ^p13 is a monovalent organic group having a fluorine atom.) The photoresist composition of claim 1, wherein the polymer [A] further comprises a structural unit (III) represented by the following formula (6).

(In formula (6), R <^1> is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a C1-C3 alkyl group, R <^2> -R <^4> is respectively independently a C1-C4 alkyl group or C4-C20 Alicyclic group, provided that R ³ and R ⁴ may be bonded to each other to form a divalent alicyclic group having 4 to 20 carbon atoms with the carbon atom to which they are bonded) The polymer of claim 1, wherein the polymer [A] further comprises at least one structural unit (IV) selected from the group consisting of a structural unit having a lactone structure, a structural unit having a cyclic carbonate structure, and a structural unit having a sultone structure. The photoresist composition. The photoresist composition of claim 1, further comprising an acid diffusion control agent [C]. The photoresist composition of claim 10, wherein the acid diffusion control agent [C] is a photodegradable base.

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