JP2000047387A - Positive type photoresist composition for exposure with far ultraviolet ray - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a positive type photoresist compsn. excellent in sensitivity to a short wavelength light source and giving a soln. excellent in aging stability when it is dissolved in an org. solvent by using a specified acid decomposable resin and a specified photo-acid generating agent. SOLUTION: The photoresist compsn. contains a compd. of formula I or II which generates sulfonic acid when irradiated with activic rays of light or radiation and a resin which contains repeating units of formula III, is decomposed by the action of the acid and increases its alkali solubility. In the formulae I and II, R1-R5 are each H, an alkyl, a cycloalkyl, an alkoxy or the like, (a), (b) and (l) are each 1-5, (m) and (n) are each 0-5, X is R-SO3 and R is an aliphatic or arom. hydrocarbon. In the formula III, Rc1-Rc8 are each H, an alkyl, a cyclic hydrocarbon, a halogen or the like, the ratio of p:q is 1:9 to 9:1 and p+q=10-100.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive photoresist composition for use in an ultra-microlithography process such as the production of an VLSI or a high-capacity microchip and other photofabrication processes. More specifically, the present invention relates to a positive photoresist composition capable of forming a high-definition pattern using a far ultraviolet region including excimer laser light.

[0002]

2. Description of the Related Art In recent years, the degree of integration of integrated circuits has been increasing more and more, and in the manufacture of semiconductor substrates such as VLSIs, processing of ultrafine patterns having a line width of less than half a micron is required. It has become In order to satisfy the need, the wavelength used in an exposure apparatus used for photolithography is becoming shorter and shorter, and now it is considered to use excimer laser light (XeCl, KrF, ArF, etc.) having a short wavelength among far ultraviolet rays. Up to now.
A chemically amplified resist is used for forming a pattern in lithography in this wavelength region.

In general, chemically amplified resists can be broadly classified into three types: so-called two-component, 2.5-component and three-component resists. The two-component system combines a compound that generates an acid by photolysis (hereinafter referred to as a photoacid generator) and a binder resin. The binder resin is a resin having in its molecule a group (also referred to as an acid-decomposable group) that decomposes under the action of an acid to increase the solubility of the resin in an alkaline developer. The 2.5-component system further contains a low-molecular compound having an acid-decomposable group in such a two-component system. The three-component system contains a photoacid generator, an alkali-soluble resin, and the above low molecular compound.

The above-mentioned chemically amplified resist is suitable for a photoresist for irradiating ultraviolet rays or far ultraviolet rays, but among them, it is necessary to further meet the required characteristics in use. For example,
When using 248 nm light of a KrF excimer laser, a hydroxystyrene-based polymer having a low light absorption is particularly used.
There has been proposed a resist composition using a polymer having an acetal group or a ketal group introduced as a protective group. JP-A-2-141636, JP-A-2-19847, JP-A-4
For example, Japanese Patent Application Laid-Open No. 5-281745 and Japanese Patent Application Laid-Open No. 5-281745 are examples. In addition, similar compositions using a t-butoxycarbonyloxy group or a p-tetrahydropyranyloxy group as an acid-decomposable group are disclosed in JP-A-2-209977 and JP-A-3-209.
206458 and JP-A-2-19847. These are 24 KrF excimer lasers.
Although suitable when using 8 nm light, sensitivity is low when using an ArF excimer laser as the light source, because the absorbance is still essentially too high. In addition, there are other disadvantages associated therewith, such as deterioration of resolution, deterioration of focus tolerance, deterioration of pattern profile, and the like, and many points still need improvement.

[0005] Accordingly, a photoresist composition for an ArF light source is a photoresist composition in which a (meth) acrylic resin having a lower absorption than a partially hydroxylated styrene resin is combined with a compound capable of generating an acid by light. Resist compositions have been proposed. For example, JP-A-7-1
No. 99467 and No. 7-252324. Among them, JP-A-6-289615 discloses a resin in which a tertiary carbon organic group is ester-bonded to oxygen of a carboxyl group of acrylic acid.

Further, Japanese Patent Application Laid-Open No. Hei 7-234511 discloses an acid-decomposable resin having both an acrylic ester and a fumaric ester as a repeating unit. It is a fact that no good performance has been obtained.

Further, a resin into which an alicyclic hydrocarbon moiety has been introduced for the purpose of imparting dry etching resistance has been proposed. However, the introduction of an alicyclic hydrocarbon moiety has a disadvantage that the system becomes extremely hydrophobic. In addition, phenomena such as difficulty in developing with an aqueous solution of tetramethylammonium hydroxide (hereinafter referred to as TMAH), which has been widely used as a resist developing solution, and peeling of the resist from the substrate during the development are observed. In response to such a resist hydrophobization, measures such as mixing an organic solvent such as isopropyl alcohol with a developing solution have been studied. Although some results have been obtained, concerns about the swelling of the resist film and the process become complicated. This does not necessarily mean that the problem has been solved. In the approach of improving the resist, many measures have been taken to supplement various hydrophobic alicyclic hydrocarbon sites by introducing a hydrophilic group.

In general, a measure has been taken to copolymerize a monomer having a carboxylic acid moiety such as acrylic acid or methacrylic acid with a monomer having an alicyclic hydrocarbon group. At the same time, although there is a tendency to improve the substrate adhesion, the dry etching resistance is deteriorated,
Further, there are many problems such as a significant decrease in resist film thickness, and the above-mentioned problems have not been solved. Further, in JP-A-7-234511, a monomer having a hydroxyl group or a cyano group in the molecule instead of a carboxylic acid group such as HEMA or acrylonitrile is copolymerized with a monomer having an alicyclic hydrocarbon group. This was aimed at solving the developing property, but it was completely insufficient.

On the other hand, in addition to the method of introducing an alicyclic hydrocarbon moiety into the side chain of the acrylate monomer, a method of imparting dry etching resistance utilizing an alicyclic hydrocarbon moiety as a polymer main chain has also been studied. I have. However, this system also has the above problem, and improvement by a similar approach is being studied. For example, Journal of Photopoly
mer Science and Technology, Vol.10, 1997, p529-534
And Journal of Photopolymer Science and Technology,
In Vol. 10, 1997, p521-528, the introduction of hydroxyl groups into the norbornene polymer main chain is studied from the viewpoint of imparting substrate adhesion. However, satisfactory results have not been obtained in both the developability and the substrate adhesion. Also, SPIE, Vol. 3049, pp. 92-105 (1988) describes a polymer obtained by ring-opening polymerization of a norbornene ring or a polymer having a norbornene ring in its main chain and having a carboxyl group and a t-butyl ester group. Compositions containing coalescence are disclosed. However, this technique also has a disadvantage that neither the substrate adhesion nor the suitability for a standard developer is practically sufficient.

Further, EP-A-789278 A2 discloses a polymer obtained by ring-opening polymerization of a norbornene ring or a polymer having a norbornene ring in a main chain and containing a resin containing an acid-decomposable group and a carboxyl group. Compositions are disclosed. WO 97/33198 discloses a photoresist composition containing a resin obtained by polymerizing a monomer having a norbornene ring having an acid-decomposable group. Also, JP-A-9-274318 discloses that
Further, a photoresist composition using a carboxylic acid is disclosed. JP-A-10-111569 discloses (A) a resin having an alicyclic skeleton in the main chain, and (B) a resin having an alicyclic skeleton in the main chain.
A radiation-sensitive resin composition that contains a radiation-sensitive acid generator, has excellent transparency to far ultraviolet rays and dry etching resistance, and provides a resist pattern with excellent substrate adhesion, sensitivity, resolution, developability, and the like. It has been disclosed.

As described above, a resin containing an acid-decomposable group generally contains an aliphatic cyclic hydrocarbon group in the molecule at the same time. Therefore, it is also true that the resin becomes hydrophobic due to these trends. On the other hand, as for the photoacid generator to be used in accordance therewith, onium salt compounds have been widely used and have achieved certain results. However, although the causes of the conventionally used onium salt compounds are unknown, they are poorly compatible during resist preparation and cause turbidity, or insoluble substances are precipitated over time, and as a result, there is a problem with stability over time. Left. Further, there is room for improvement such as a decrease in sensitivity over time.

[0012]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the problem of the performance improvement technology inherent in microphotofabrication using far ultraviolet light, particularly ArF excimer laser light. An object of the present invention is to provide a positive photoresist composition having good compatibility with a resin when dissolved in an organic solvent, excellent stability over time of the solution, and excellent sensitivity to a short-wavelength light source.

[0013]

Means for Solving the Problems As a result of intensive studies on the constituent materials of a resist composition in a positive-type chemical amplification system, the present inventors have found that a specific acid-decomposable resin and a specific photoacid generator are used. It was found that the object of the present invention was achieved, and the present invention was achieved. That is, the above object is achieved by the following constitutions.

(1) The following general formula (I) or (I) which generates a sulfonic acid upon irradiation with an actinic ray or radiation.
Deep ultraviolet light exposure, comprising: a compound represented by the formula (I); and a resin containing a repeating unit represented by the following general formula (cI) and decomposed by the action of an acid to increase the solubility in alkali. Positive photoresist composition.

[0015]

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In the formula, each of R _{1 to} R ₅ may be a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, or a substituent. Alkoxy group, alkoxycarbonyl group which may have a substituent, acyl group which may have a substituent, acyloxy group which may have a substituent, nitro group, halogen atom, hydroxyl group, carboxyl group Represents a: 1 to 5, b: 1 to 5, l: 1 to 5, m: 0 to 5, n: 0 to 5.

However, at least one of R ₁ and R ₂ has an alkyl group which has 5 or more carbon atoms and may have a substituent, a cycloalkyl group which may have a substituent and a substituent. An alkoxy group which may be substituted, an alkoxycarbonyl group which may have a substituent, an acyl group which may have a substituent, and an acyloxy group which may have a substituent. When 1 + m + n = 1, R ₃ represents an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, or a substituent. Represents an optionally substituted alkoxycarbonyl group, an optionally substituted acyl group, and an optionally substituted acyloxy group. X represents R—SO ₃ , R represents an aliphatic hydrocarbon group which may have a substituent, or an aromatic hydrocarbon group which may have a substituent.

[0018]

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In the formula, R _{c1 to} R _c8 may be the same or different and include a hydrogen atom, an alkyl group which may have a substituent, a cyclic hydrocarbon group which may have a substituent, and a halogen atom. An atom, a cyano group, a group that decomposes under the action of an acid, or-
Represents C (= O) _{-YAR c9} . p / q: 1 / 9~9 / 1 p + q: 10~100 Y: oxygen atom, a sulfur _{atom, -NH -, - NHSO 2 -} ,
-NHSO 2 divalent linking group selected from _{2 NH-, R c9: -COOH,} -COOR c10 (R c10 definition is synonymous with R _c11 and below lactone structure), - CN, hydroxyl, substituted An optionally substituted alkoxy group, -CO-
NH-R _c11, represents a -CO-NH-SO ₂ -R _c11 or the following lactone structure. R _c11 : an alkyl group which may have a substituent, a cyclic alkyl group which may have a substituent, A: a single bond, an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester A single group selected from the group consisting of a group, an amide group, a sulfonamide group, a urethane group, and a urea group, or a combination of two or more groups.

[0020]

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R _{29 to} R ₃₆ may be the same or different;
Represents a hydrogen atom or an alkyl group which may have a substituent. a and b each represent 1 or 2.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the compounds used in the present invention will be described in detail. [1] Photoacid generator represented by general formula [I] or [II] In the general formula [I] or [II], the alkyl group of R _{1 to} R ₅ may have a substituent. Good, methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, t-amyl, decanyl, dodecanyl And those having 1 to 25 carbon atoms such as a hexadecanyl group. As the cycloalkyl group, a cyclopropyl group which may have a substituent,
Those having 1 to 25 carbon atoms such as a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a cyclododecanyl group, a cyclohexadecanyl group and the like can be mentioned. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group or a t-butoxy group, a pentyloxy group, and a t -Amyloxy group, n-hexyloxy group, n-octyloxy group, n-
Those having 1 to 25 carbon atoms such as a dodecaneoxy group are exemplified. Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, an isobutoxycarbonyl group, a sec-butoxycarbonyl group or a t, which may have a substituent. -Butoxycarbonyl group, pentyloxycarbonyl group, t-amyloxycarbonyl group, n-hexyloxycarbonyl group, n-octyloxycarbonyl group, n-dodecaneoxycarbonyl group, etc. No. The acyl group may have a substituent and has 1 carbon atom such as a formyl group, an acetyl group, a butyryl group, a valeryl group, a hexanoyl group, an octanoyl group, a t-butylcarbonyl group, and a t-amylcarbonyl group. To 25. Examples of the acyloxy group include an acetoxy group, an ethylyloxy group, a butyryloxy group, a t-butyryloxy group, and a t which may have a substituent.
-Amylyloxy group, n-hexanecarbonyloxy group,
Examples thereof include those having 1 to 25 carbon atoms such as an n-octanecarbonyloxy group, an n-dodecanecarbonyloxy group, an n-hexadecanecarbonyloxy group, and the like. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

As a substituent for these groups, an alkoxy group having 1 to 4 carbon atoms, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), an acyl group, an acyloxy group, a cyano group, a hydroxyl group, Carboxy group,
Examples thereof include an alkoxycarbonyl group and a nitro group. As described above, at least one of R ₁ and R ₂ represents an alkyl group having 5 or more carbon atoms which may have a substituent, a cycloalkyl group which may have a substituent, or a substituent. It represents an alkoxy group which may have, an alkoxycarbonyl group which may have a substituent, an acyl group which may have a substituent, and an acyloxy group which may have a substituent. As the above substituent having 5 or more carbon atoms,
Among the above examples, those having 5 to 25 carbon atoms can be mentioned. When l + m + n = 1, R ₃ represents an alkyl group optionally having a substituent, a cycloalkyl group optionally having a substituent, an alkoxy group optionally having a substituent, a substituent Represents an alkoxycarbonyl group which may have a substituent, an acyl group which may have a substituent, and an acyloxy group which may have a substituent.

Among the above, alkyl groups which may have a substituent of R _{1 to} R ₅ include methyl, ethyl, propyl, isopropyl, butyl, t-butyl, n- A pentyl group, a t-amyl group, an n-hexyl group, an n-octyl group, and a decanyl group are preferable.As the cycloalkyl group, a cyclohexyl group, a cyclooctyl group, and a cyclododecanyl group which may have a substituent may be used. Preferably, the alkoxy group may have a substituent,
Methoxy, ethoxy, isopropoxy, n-butoxy, sec-butoxy, t-butoxy, pentyloxy, t-amyloxy, n-hexyloxy,
An n-octyloxy group and an n-dodecaneoxy group are preferable. As the alkoxycarbonyl group, a methoxycarbonyl group, an ethoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, and an sec- Butoxycarbonyl group, t-butoxycarbonyl group, pentyloxycarbonyl group, t-amyloxycarbonyl group, n-hexyloxycarbonyl group,
An n-octyloxycarbonyl group and an n-dodecaneoxycarbonyl group are preferable, and as the acyl group, a formyl group, an acetyl group, a butyryl group, which may have a substituent,
A valeryl group, a hexanoyl group, an octanoyl group, a t-butylcarbonyl group, and a t-amylcarbonyl group are preferred.As the acyloxy group, an acetoxy group, an ethylyloxy group, a butyryloxy group, which may have a substituent,
-Butyryloxy group, t-amylyloxy group, n-hexanecarbonyloxy group and n-octanecarbonyloxy group are preferred.

[0025] Among the above, among those having 5 or more carbon atoms,
The alkyl group which may have a substituent is preferably an n-pentyl group, a t-amyl group, an n-hexyl group, an n-octyl group, a decanyl group, and a cycloalkyl group which may have a substituent. As the alkyl group, a cyclohexyl group, a cyclooctyl group, or a cyclododecanyl group is preferable, and as the alkoxy group, a pentyloxy group, a t-amyloxy group, a hexyloxy group, an n-
An octyloxy group and a dodecaneoxy group are preferable, and may have a substituent.Examples of the alkoxycarbonyl group include a pentyloxycarbonyl group, a t-amyloxycarbonyl group, a hexyloxycarbonyl group, an n-octyloxycarbonyl group, A dodecaneoxycarbonyl group is preferable, and an acyl group which may have a substituent includes, for example, a pareryl group, a hexanoyl group, an octanoyl group, a t-group.
-Amylcarbonyl group is preferable, and the acyloxy group which may have a substituent includes a t-amylyloxy group,
An n-hexanecarbonyloxy group and an n-octanecarbonyloxy group are preferred. Substituents for these groups include methoxy, ethoxy, t-butoxy, chlorine, bromine, cyano, hydroxyl, methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl, t-amyloxycarbonyl Groups are preferred.

The general expressions used in the present invention [I] or sulfonium, iodonium compound represented by [II], the counter anion, X ^- as, using a sulfonic acid having a specific structure as described above. Examples of the aliphatic hydrocarbon group which may have a substituent of R in the counter anion include a linear or branched alkyl group having 1 to 20 carbon atoms, or a cyclic alkyl group. R may be an aromatic group which may have a substituent. As the alkyl group for R, a methyl group, an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, which may have a substituent,
Examples thereof include those having 1 to 20 carbon atoms such as an n-octyl group, a 2-ethylhexyl group, a decyl group and a dodecyl group. The cyclic alkyl group may have a substituent,
Examples thereof include a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a cyclododecyl group, an adamantyl group, a norbornyl group, a camphor group, a tricyclodecanyl group, and a menthyl group. Examples of the aromatic group include a phenyl group and a naphthyl group which may have a substituent. Among the above, as the alkyl group which may have a substituent of R, a methyl group, a trifluoromethyl group,
Ethyl group, pentafluoromethyl group, 2,2,2-trifluoroethyl group, n-propyl group, n-butyl group, nonafluorobutyl group, n-pentyl group, n-hexyl group, n-octyl group, hepta Decafluorooctyl group,
Examples of the 2-ethylhexyl group, decyl group, dodecyl group, and cyclic alkyl group include a cyclopentyl group, a cyclohexyl group, and a camphor group. The aromatic group may have a substituent, a phenyl group, a naphthyl group,
Pentafluorophenyl group, p-toluyl group, p-fluorophenyl group, p-chlorophenyl group, p-hydroxyphenyl group, p-methoxyphenyl group, dodecylphenyl group, mesityl group, triisopropylphenyl group, 4-
Examples thereof include a hydroxy-1-naphthyl group and a 6-hydroxy-2-naphthyl group.

Among the above substituents, more preferred R
Specific examples of the ₁ to R _5, a methyl group, an ethyl group, a propyl group, an isopropyl group, n- butyl group, t- butyl group, n- pentyl group, t-amyl group, n- hexyl group,
n-octyl group, cyclohexyl group, methoxy group, ethoxy group, isopropoxy group, n-butoxy group, t-butoxy group, pentyloxy group, t-amyloxy group, hexyloxy group, n-octyloxy group, methoxycarbonyl group , Ethoxycarbonyl group, n-butoxycarbonyl group, t-butoxycarbonyl group, t-amyloxycarbonyl group, hexyloxycarbonyl group, n-octyloxycarbonyl group, formyl group, acetyl group, butyryl group, hexanoyl group, octanoyl group , T-butylcarbonyl group, t-amylcarbonyl group, acetoxy group, ethylyloxy group, butyryloxy group, t-butyryloxy group, t-amylyloxy group, n-hexanecarbonyloxy group, n-octanecarbonyloxy group, hydroxyl group, Chlorine atom, bromine atom, Is the Toro group. More preferred specific examples having 5 or more carbon atoms include an n-pentyl group, a t-amyl group, an n-hexyl group, an n-octyl group, a decanyl group,
Cyclohexyl group, pentyloxy group, t-amyloxy group, hexyloxy group, n-octyloxy group, dodecaneoxy group, pentyloxycarbonyl group, t-amyloxycarbonyl group, hexyloxycarbonyl group, n-
Octyloxycarbonyl group, dodecaneoxycarbonyl group, pareryl group, hexanoyl group, octanoyl group,
t-amylcarbonyl group, t-amylyloxy group, n-
A hexanecarbonyloxy group and an n-octanecarbonyloxy group. Specific examples of the more preferable sulfonic acid substituent R include a methyl group, a trifluoromethyl group, an ethyl group, a pentafluoromethyl group, a 2,2,2-trifluoroethyl group, an n-butyl group, a nonafluorobutyl group, n
-Hexyl group, n-octyl group, heptadecafluorooctyl group, 2-ethylhexyl group, camphor group, phenyl group, naphthyl group, pentafluorophenyl group, p-toluyl group, p-fluorophenyl group, p-chlorophenyl group, p-methoxyphenyl group, dodecylphenyl group, mesityl group, triisopropylphenyl group, 4-hydroxy-1-naphthyl group and 6-hydroxy-2-naphthyl group.

The total number of carbon atoms of the generated acid is preferably 1 to 30. The number is more preferably 1 to 28, and still more preferably 1 to 25. If the total number of carbon atoms is less than one, pattern formation is hindered, such as formation of a t-top shape. If the total number is more than 30, undesired development residues are generated. Hereinafter, specific examples of the compound represented by the general formula [I] or [II] as the acid generator of the present invention include the following [I-1] to [I-18] and [II-1] to
[II-20] is shown, but the present invention is not limited to this. These compounds are used alone or in combination of two or more.

[0029]

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[0030]

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[0031]

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[0032]

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[0033]

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The general formula [I] or a compound represented by [II], for example the corresponding Cl ^- salt (formula [I] or [II] with X ^- the Cl ^- compounds substituted with) and, X ^- Y ⁺
(X ⁻ has the same meaning as in formula [I] or [II], and Y ⁺ is H ⁺ , Na ⁺ , K ⁺ , NH ₄ ⁺ , N (C
H ₃ ) ₄ ^{+ and} other cations. ) Can be synthesized by salt exchange in an aqueous solution. In addition to the above chlorides, hydroxides or methanesulfonates can be subjected to similar salt exchange. The amount of the photoacid generator represented by the general formula [I] or [II] in the composition is as follows:
In the total solid content of the positive photoresist composition, 0.01 to
It is preferably 5% by weight, more preferably 0.03 to 4% by weight, and still more preferably 0.05 to 3% by weight. 0.0
If the amount is less than 1% by weight, the sensitivity is lowered. If the amount is more than 5% by weight, the optical absorption is excessively increased.

[2] Acid-decomposable resin containing a repeating unit represented by the general formula (cI) The resin used in the present invention, which is decomposed by the action of an acid and has increased solubility in alkali, is represented by the following general formula (cI). Including repeat units that are

[0036]

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In the above general formula (cI), R _{c1 to} R _c8
Examples of the group decomposed by the action of an acid (also referred to as an acid-decomposable group) include a group represented by —C (＝ O) —X ₁ —R ₀ . Here, R ₀ is a t-butyl group,
tertiary alkyl groups such as t-amyl group, isobornyl group, 1
-An ethoxyethyl group, a 1-butoxyethyl group, a 1-isobutoxyethyl group, a 1-alkoxyethyl group such as a 1-cyclohexyloxyethyl group, a 1-methoxymethyl group,
An alkoxymethyl group such as -ethoxymethyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a trialkylsilyl group, and a 3-oxocyclohexyl group. Here, X ₁ has the same meaning as Y.

The alkyl group for R _{c1 to} R _c8 and R _c11 is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, more preferably a linear or branched alkyl group having 1 to 6 carbon atoms. Alkyl group, more preferably methyl group, ethyl group, propyl group, isopropyl group, n
-Butyl group, isobutyl group, sec-butyl group and t-butyl group.

Examples of the cyclic hydrocarbon group for R _{c1 to} R _c8 include a cyclic alkyl group and a bridged hydrocarbon group, such as a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and a 2-methyl-2-adamantyl group. , Norbornyl, boronyl, isobornyl, tricyclodecanyl, dicyclopentenyl, nobornane epoxy, menthyl, isomenthyl, neomenthyl, tetracyclododecanyl and the like.

_Examples of the alkoxy group for R _c9 include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group.

As the cyclic alkyl group for R _c11 ,
Cyclopropyl group, cyclopentyl group, cyclohexyl group, adamantyl group, 2-methyl-2-adamantyl group, norbornyl group, boronyl group, isobornyl group, tricyclodecanyl group, dicyclopentenyl group, nobornane epoxy group, menthyl group, Examples include an isomenthyl group, a neomenthyl group, and a tetracyclododecanyl group.

Further substituents in the above-mentioned alkyl group, cyclic alkyl group and alkoxy group include a hydroxyl group, a halogen atom, a carboxyl group, an alkoxy group, an acyl group, a cyano group and an acyloxy group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. Examples of the acyl group include a formyl group and an acetyl group. Examples thereof include an acetoxy group.

Examples of the alkylene group and substituted alkylene group in A include the following groups. -[C (R _a ) (R _b )] _r-wherein R _a and R _b each represent a hydrogen atom, an alkyl group, a substituted alkyl group, a halogen atom, a hydroxyl group, or an alkoxy group; The alkyl group is preferably a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group and a butyl group, and more preferably selected from the group consisting of a methyl group, an ethyl group, a propyl group and an isopropyl group. Represents a substituent. Examples of the substituent of the substituted alkyl group include a hydroxyl group, a halogen atom and an alkoxy group. Examples of the alkoxy group include those having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group. r represents an integer of 1 to 10. In the general formula (cI), examples of the halogen atom include a chlorine atom, a bromine atom, a fluorine atom, and an iodine atom.

In the general formula (cI), the acid content
A decomposable group and -C (= O) -YAR _c9Is the same repeating unit
May be included in both positions or included in separate repeating units
May be.

The acid-decomposable resin used in the present invention can be obtained by polymerizing a monomer having a norbornene skeleton and, if necessary, conducting a polymer reaction. The polymerization reaction can be obtained by radical polymerization using a general radical initiator such as an azo initiator, but is more preferably synthesized by ring-opening polymerization using a coordination polymerization catalyst such as a transition metal complex. You. The resin obtained by the ring-opening polymerization is preferably reduced and used from the viewpoint of stability and optical absorption. The acid-decomposable resin contains, in addition to one or more monomer repeating units of the general formula (cI), dry etching resistance, suitability for a standard developer, substrate adhesion, resist profile, and general requirements for resist. It can be used as a copolymer with various monomer repeating units for the purpose of adjusting the resolution, heat resistance, sensitivity and the like. Preferred examples of the copolymer component include a repeating unit represented by the following general formula (cV) or (cVI).

[0046]

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Here, Z is an oxygen atom, -NH-, -N
_{(-R C3) -, - N} (-OSO 2 R C3) - represents, R _C3
Represents a (substituted) alkyl group and a (substituted) cyclic alkyl group as described above. Preferred combinations of repeating units of the acid-decomposable resin include the following. However, it is not limited to this.

[0048]

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[0049]

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[0050]

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[0051]

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[0052]

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[0053]

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[0054]

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In the acid-decomposable resin, the group decomposed by the action of an acid is contained in the general formula (cI) or in the copolymerization component.

In the acid-decomposable resin, the molar ratio of each repeating unit depends on the dry etching resistance of the resist, the suitability for a standard developing solution, the substrate adhesion, the resist profile, and the resolution, heat resistance, which is a general requirement of the resist. ,
It is set as appropriate to adjust sensitivity and the like.

However, the content of the repeating unit represented by the general formula (cI) in the acid-decomposable resin is not less than 10 mol%, preferably not less than 20 mol%, more preferably not less than all monomer repeating units. Is 30 mol% or more. In the acid-decomposable resin, the content of the repeating unit containing an acid-decomposable group is 10 to 90 mol%, preferably 15 to 85 mol%, more preferably 20 to 90 mol% of all the monomer repeating units.
~ 80 mol%. The content of the carboxyl group for imparting adhesiveness is 0.05 to 2.0 meq / g, preferably 0.1 to 1.8 meq / g, more preferably 0.3 to 1 in the resin. 0.5 meq / g.

Hereinafter, specific examples of the repeating unit represented by the general formula (cI) constituting the resin which is decomposed by the action of an acid to increase the solubility in alkali are shown below, but the content of the present invention is not limited to these. It is not something that can be done.

[0059]

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[0060]

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[0061]

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[0062]

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[0063]

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[0064]

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[0065]

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[0066]

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[0067]

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[0068]

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[0069]

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[0070]

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[0071]

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[0072]

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[0073]

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[0074]

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The content of the repeating unit (general formula (cV) or (cVI)) based on the above-mentioned additional monomer in the resin is determined by the total number of moles of the repeating structural unit represented by the general formula (cI) Is preferably 99 mol% or less, more preferably 90 mol% or less, still more preferably 80 mol% or less. If it exceeds 99 mol%, the effect of the present invention is not sufficiently exhibited, so that it is not preferable.

Such an acid-decomposable resin can be further copolymerized as a repeating unit with the following monomers as long as the effects of the present invention can be effectively obtained, but are not limited thereto. Not something. Thereby, the performance required for the resin, particularly (1) solubility in a coating solvent,
(2) film-forming properties (glass transition point), (3) alkali developability, (4) film loss (hydrophilic / hydrophobic, alkali-soluble group selection), (5) adhesion of unexposed portions to substrate, (6) Fine adjustment of dry etching resistance becomes possible. As such a comonomer, for example, acrylates,
Examples thereof include compounds having one addition-polymerizable unsaturated bond selected from methacrylates, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, and the like.

Specifically, for example, acrylic esters such as alkyl (the alkyl group has 1 to 1 carbon atoms)
Acrylates (for example, methyl acrylate, ethyl acrylate, propyl acrylate, amyl acrylate, cyclohexyl acrylate, ethylhexyl acrylate, octyl acrylate, acrylate-
t-octyl, chloroethyl acrylate, 2-hydroxyethyl acrylate 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate, trimethylolpropane monoacrylate, pentaerythritol monoacrylate, benzyl acrylate, methoxybenzyl acrylate, furfuryl acrylate, Tetrahydrofurfuryl acrylate, etc.);

Methacrylic esters such as alkyl (alkyl having preferably 1 to 10 carbon atoms) methacrylate (eg, methyl methacrylate,
Ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, amyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate,
Benzyl methacrylate, chlorobenzyl methacrylate, octyl methacrylate, 2-hydroxyethyl methacrylate, 4-hydroxybutyl methacrylate,
5-hydroxypentyl methacrylate, 2,2-dimethyl-3-hydroxypropyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, etc.);

Acrylamides, for example, acrylamide, N-alkylacrylamide, (where the alkyl group has 1 to 10 carbon atoms, for example, methyl, ethyl, propyl, butyl, t-butyl, heptyl, octyl) Group, cyclohexyl group, hydroxyethyl group, etc.), N, N-dialkylacrylamide (alkyl group having 1 to 10 carbon atoms, for example, methyl group, ethyl group, butyl group, isobutyl group, ethylhexyl group, Cyclohexyl group, etc.), N-
Hydroxyethyl-N-methylacrylamide, N-2
-Acetamidoethyl-N-acetylacrylamide and the like;

Methacrylamides, for example, methacrylamide, N-alkyl methacrylamide (the alkyl group having 1 to 10 carbon atoms, for example, methyl, ethyl, t-butyl, ethylhexyl, hydroxyethyl, cyclohexyl) Groups, etc.), N, N-dialkylmethacrylamide (an alkyl group includes an ethyl group, a propyl group, a butyl group, etc.), N-hydroxyethyl-N-methylmethacrylamide and the like;

Allyl compounds such as allyl esters (eg, allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate), allyloxy Ethanol, etc .;

Vinyl ethers such as alkyl vinyl ethers (eg, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethylhexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl vinyl ether, 2-ethyl Butyl vinyl ether, hydroxyethyl vinyl ether, diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether, etc.);

Vinyl esters such as vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxy acetate, vinyl butoxy acetate, Vinyl acetoacetate, vinyl lactate, vinyl-β-phenylbutyrate, vinylcyclohexylcarboxylate and the like;

Dialkyl itaconates (eg, dimethyl itaconate, diethyl itaconate, dibutyl itaconate, etc.); dialkyl esters of fumaric acid (eg, dibutyl fumarate, etc.) or monoalkyl esters;
Acrylic acid, methacrylic acid, crotonic acid, itaconic acid,
Examples include maleic anhydride, maleimide, acrylonitrile, methacrylonitrile, maleilenitrile, and the like.

In addition, any addition-polymerizable unsaturated compound copolymerizable with the above-mentioned various repeating units may be used. Further, the content of the repeating unit based on the monomer of the further copolymerization component in the resin can also be appropriately set according to the desired performance of the resist, but generally, the total of the essential repeating units is calculated. It is preferably at most 99 mol%, more preferably at most 90 mol%, even more preferably at most 80 mol%, based on the total mole number.

The molecular weight of the acid-decomposable resin as described above is preferably 1,0 in terms of weight average (Mw: polystyrene standard).
00 to 1,000,000, more preferably 1,500
~ 500,000, more preferably 2,000 ~ 20
000, more preferably 2,500-100,
000, and the larger the value, the better the heat resistance and the like, but the lower the developability and the like.

In the positive photoresist composition of the present invention, the amount of the acid-decomposable resin added to the whole composition is preferably 40 to 99.99% by weight, more preferably 50 to 99.99% by weight, based on the whole resist solids. 97% by weight.

Next, in the positive photoresist composition of the present invention, a compound (photoacid generator) which generates an acid upon irradiation with actinic rays or radiation represented by the above general formula [I] or [II] is added. The photoacid generator that can be used in combination will be described.

The photoacid generator needs to satisfy two properties. That is, (1) transparency to exposure light (provided that there is no light bleaching property) and (2) sufficient photodegradability to secure resist sensitivity. However, at present, there is no clear guideline for molecular design that satisfies such contradictory requirements. For example, the following examples can be given. That is, JP-A-7-25846,
Aliphatic alksulfonium salts having a 2-oxocyclohexyl group and N-hydroxysuccinimide sulfonates described in JP-A-7-28237, JP-A-7-92675 and JP-A-8-27102 And the like. And J. Phot
Opolym. Sci. Technol., Vol 7, No3, p 423 (1994), etc., and sulfonium salts represented by the following general formula (VI), disulfones represented by the following general formula (VII) And compounds represented by the following general formula (VIII).

[0090]

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Here, R _{12 to} R ₁₅ each represent an alkyl group or a cyclic alkyl group. These may be the same or different from each other. Further, N-hydroxymaleimide sulphonates represented by the following general formula (IX) are also suitable.

[0092]

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Here, R ₁₆ and R ₁₇ may be the same or different and represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group. R ₁₆ and R ₁₇ may be bonded via an alkylene group to form a ring. R ₁₈ represents an alkyl group, a perfluoroalkyl group, a cycloalkyl group or a substituted camphor. Such N-hydroxymaleimide sulphonates are particularly preferred in terms of photosensitivity.

As the alkyl group having 1 to 6 carbon atoms for R ₁₆ and R ₁₇ in the general formula (IX), a methyl group,
Ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-pentyl group,
An n-hexyl group can be mentioned. Among them, preferred are a methyl group, an ethyl group and a propyl group, and a methyl group and an ethyl group are more preferred. Examples of the cycloalkyl group having 6 or less carbon atoms include a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group. Preferably, they are a cyclopentyl group and a cyclohexyl group. R ₁₆ ,
Examples of the case where R ₁₇ forms a ring with each other by an alkylene chain include a case where a cyclohexyl group, a norbornyl group, and a tricyclodecanyl group are formed.

The alkyl group represented by R ₁₈ is a straight-chain alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group and a propyl group.
Alkyl groups, isopropyl groups, isobutyl groups, t
Examples thereof include a branched alkyl group having 1 to 20 carbon atoms such as an tert-butyl group and a neopentyl group. It is preferably a linear or branched alkyl group having 1 to 16 carbon atoms, and more preferably 4 to 15 carbon atoms.
Linear or branched alkyl groups. Examples of the perfluoroalkyl group include a trifluoromethyl group, a pentafluoroethyl group and other straight-chain carbon atoms having 1 to 20 carbon atoms.
And a branched perfluoroalkyl group having 1 to 20 carbon atoms such as a perfluoroalkyl group, a heptafluoroisopropyl group, and a nonafluoro tert-butyl group. Preferably, it is a linear or branched perfluoroalkyl group having 1 to 16 carbon atoms. As the cyclic alkyl group, a monocyclic cyclic alkyl group such as a cyclopentyl group and a cyclohexyl group, a decalyl group,
Examples thereof include a plurality of cyclic alkyl groups such as a norbornyl group and a tricyclodecanyl group.

The amount of such a photoacid generator that can be used in combination is preferably 0.01 to 5% by weight, more preferably 0.03% by weight, based on the total solid content of the positive photoresist composition. To 3% by weight, more preferably 0.05 to 2% by weight.

In the positive photoresist composition of the present invention, the following photoacid generator may be used in addition to the above photoacid generator.

The amount of the photoacid generator which can be used together as described below in the composition is 2% by weight or less, more preferably 1% by weight in the solid content of the whole positive photoresist composition.
The following is good. For example, SISchlesinger, Photogr.Sci.E
ng., 18,387 (1974), TSBal etal, Polymer, 21,423 (198
0) etc., U.S. Pat.No.4,069,055
No. 4,069,056, Re 27,992, JP-A-3-140,14
Ammonium salts described in No. 0 etc., DCNecker etal, Macr
omolecules, 17, 2468 (1984), CSwen et al, Teh, Proc. Co.
nf.Rad.Curing ASIA, p478 Tokyo, Oct (1988), U.S. Pat.Nos. 4,069,055, 4,069,056, phosphonium salts described in JVCrivello et al., Macromorecules, 10 (6), 1307.
(1977), Chem. & Eng. News, Nov. 28, p31 (1988), European Patent Nos. 104,143, 339,049, 410,201, JP-A-2-150,848, JP-A-2-296,514, etc. Described iodonium salts, JVCrivello etal, Polymer J. 17, 73 (198
5), JVCrivello et al. J. Org. Chem., 43, 3055 (1978)
, WRWatt et al., J. Polymer Sci., Polymer Chem. Ed., 2
2,1789 (1984), JVCrivello etal, Polymer Bull., 14,
279 (1985), JVCrivello etal, Macromorecules, 14 (5),
1141 (1981), JVCrivello et al, J. PolymerSci., Polym
er Chem. Ed., 17, 2877 (1979), EP 370,693,
No. 161,811, No. 410,201, No. 339,049, No. 233,56
No. 7, 297,443, 297,442, U.S. Pat.
No. 377, No. 3,902,114, No. 4,760,013, No. 4,734,44
No. 4, No. 2,833,827, Dokoku Patent No. 2,904,626, No. 3,
Nos. 604,580 and 3,604,581, and the sulfonium salts described in JVCrivello et al., Macromorecules, 10 (6), 1307 (19
77), JVCrivello etal, J. PolymerSci., Polymer Che
m.Ed., 17,1047 (1979), etc.
S.Wen etal, Teh, Proc.Conf.Rad.Curing ASIA, p478 Toky
o, Oct (1988) and the like onium salts such as arsonium salts, U.S. Pat.No. 3,905,815, JP-B-46-4605, JP-A-48-36281, JP-A-55-32070, JP-A-60 -239736
No., JP-A-61-169835, JP-A-61-169837, JP-A-61-169837
No. 62-58241, JP-A-62-212401, JP-A-63-70243,
Organic halogen compounds described in JP-A-63-298339, etc.
Meier et al., J. Rad. Curing, 13 (4), 26 (1986), TPGill
etal, Inorg.Chem., 19, 3007 (1980), D. Astruc, Acc.
Res., 19 (12), 377 (1896), and organic metal / organic halides described in JP-A-2-14145, S. Hayase et al., J. Polym
er Sci., 25, 753 (1987), E. Reichmanis et al., J. Pholimer
Sci., Polymer Chem. Ed., 23, 1 (1985), QQ Zhu et al., J.
Photochem., 36, 85, 39, 317 (1987), B. Amit etal, Tetrahe
dron Lett., (24) 2205 (1973), DHR Barton et al., J. Chem.
Soc., 3571 (1965), PMCollins et al., J. Chem.SoC., Per
kin I, 1695 (1975), M. Rudinstein et al, Tetrahedron Le
tt., (17), 1445 (1975), JWWalker etal J. Am. Chem. So
c., 110, 7170 (1988), SCBusman et al, J. Imaging Techn
ol., 11 (4), 191 (1985), HMHoulihan et al, Macormolecu
les, 21, 2001 (1988), PM Collins et al., J. Chem. Soc., Che
m.Commun., 532 (1972), S.Hayase etal, Macromolecules, 1
8,1799 (1985), E. Reichmanisetal, J. Electrochem. Soc.,
Solid State Sci.Technol., 130 (6), FMHoulihan eta
1, Macromolcules, 21, 2001 (1988), European Patent 0290,750
Nos. 046,083, 156,535, 271,851, 0,
U.S. Pat.Nos. 3,901,710 and 4,181,531
, A photoacid generator having an o-nitrobenzyl-type protecting group described in JP-A-60-198538, JP-A-53-133022, etc.
TUNOOKA etal, Polymer Preprints Japan, 35 (8), G. Bern
er etal, J.Rad.Curing, 13 (4), WJMijs etal, Coating
Technol., 55 (697), 45 (1983), Akzo, H. Adachi et al, Pol
ymer Preprints, Japan, 37 (3), European Patent No. 0199,672,
No. 84515, No. 044,115, No. 618,564, No. 0101,122
No. 4,371,605, U.S. Pat.
64-18143, JP-A-2-245756, compounds that generate sulfonic acid upon photolysis represented by iminosulfonate and the like described in JP-A-3-140109, and JP-A-61-166544. The disulfone compounds described above can be exemplified.

Further, a group which generates an acid by these lights,
Alternatively, a compound having a compound introduced into a main chain or a side chain of a polymer, for example, MEWoodhouse et al., J. Am. Chem.
c., 104, 5586 (1982), SPPappas et al, J. Imaging Sc
i., 30 (5), 218 (1986), S. Kondoetal, Makromol.Chem., Ra
pid Commun., 9,625 (1988), Y.Yamada et al., Makromol.C
hem., 152, 153, 163 (1972), JVCrivello etal, J. Polym
erSci., Polymer Chem. Ed., 17,3845 (1979), U.S. Patent No. 3,849,137, Dokoku Patent No. 3,914,407, JP-A-63-266.
No. 53, JP-A-55-164824, JP-A-62-69263, JP-A-Showa
63-146038, JP-A-63-163452, JP-A-62-153853
And the compounds described in JP-A-63-146029 and the like can be used.

Further, VNRPillai, Synthesis, (1), 1 (198
0), A. Abad etal, Tetrahedron Lett., (47) 4555 (1971),
DHR Barton et al., J. Chem. Soc., (C), 329 (1970), U.S. Pat. No. 3,779,778, EP 126,712, and the like, can also be used compounds which generate an acid by light.

Among the compounds which can be used in combination and which generate an acid by being decomposed by irradiation with actinic rays or radiation, those which are particularly effectively used are exemplified below.

[0102]

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The positive photoresist composition is suitable for improving the alkali solubility of the system and for adjusting the glass transition temperature of the system to prevent the film from becoming brittle and from deteriorating the heat resistance. An alkali-soluble low molecular weight compound may be added. Examples of the alkali-soluble low molecular weight compound include a dialkyl sulfonamide compound, a dialkyl sulfonyl imide (—SO ₂ —NH—CO—) compound, and a dialkyl disulfonyl imide (—SO ₂ —NH
Compounds containing an acidic group in the molecule, such as —SO ₂ —) compounds, may be mentioned. The content of the alkali-soluble low molecular compound is 4 to the binder resin.
The content is preferably 0% by weight or less, more preferably 30% by weight or less, and further preferably 25% by weight or less.

The positive photosensitive composition of the present invention may further contain, if necessary, an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer, a surfactant, a photosensitizer, an organic basic compound, and a developer. A compound or the like which promotes solubility can be contained.

The photosensitive composition of the present invention is dissolved in a solvent capable of dissolving each of the above components, and coated on a support. As the solvent used here, ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate , Propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate,
Ethyl ethoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N, N-dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, tetrahydrofuran and the like are preferable, and these solvents are used alone or in combination.

Among the above, preferred solvents are 2-
Heptanone, γ-butyrolactone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate , N-methylpyrrolidone and tetrahydrofuran.

A surfactant may be added to the above solvents. Specifically, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether, polyoxyethylene octyl phenol ether,
Polyoxyethylene alkyl allyl ethers such as polyoxyethylene nonylphenol ether, polyoxyethylene / polyoxypropylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, Sorbitan fatty acid esters such as sorbitan tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate Surfactants such as polyoxyethylene sorbitan fatty acid esters such as acrylates, etc .; 303, EF352 (manufactured by Shin Akita Kasei Co., Ltd.), Megafac F171, F173 (manufactured by Dainippon Ink Co., Ltd.), Flora - de FC430, FC43
1 (manufactured by Sumitomo 3M Limited), Asahi Guard AG71
0, Surflon S-382, SC101, SC102,
Fluorinated surfactants such as SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), and acrylic or methacrylic (co) polymerized polyflow No. 75, no. 95 (manufactured by Kyoeisha Yushi Kagaku Kogyo KK) and the like. The amount of these surfactants is usually 2 parts by weight or less, preferably 1 part by weight or less, per 100 parts by weight of the solids in the composition of the present invention. These surfactants may be added alone or in some combination.

The positive photoresist composition of the present invention is applied on a substrate to form a thin film. The thickness of this coating film is preferably from 0.4 to 1.5 μm. Spinning the photosensitive composition onto a substrate (eg, silicon / silicon dioxide coating) such as used in the manufacture of precision integrated circuit devices;
After coating by an appropriate coating method such as a coater or the like, exposure is performed through a predetermined mask, baking and development are performed, whereby a good resist pattern can be obtained. Here, the exposure light is preferably far ultraviolet light having a wavelength of 250 nm or less, more preferably 220 nm or less. Specifically, a KrF excimer laser (248 nm), an ArF excimer laser (193 nm), an F ₂ excimer laser (157 nm), an X-ray, an electron beam, and the like can be given.

Examples of the developer for the photosensitive composition of the present invention include:
Sodium hydroxide, potassium hydroxide, sodium carbonate,
Inorganic alkalis such as sodium silicate, sodium metasilicate and aqueous ammonia, primary amines such as ethylamine and n-propylamine, secondary amines such as diethylamine and di-n-butylamine, and triethylamine and methyldiethylamine Use alkaline aqueous solutions such as triamines, alcoholamines such as dimethylethanolamine and triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide, and cyclic amines such as pyrrole and pichelidine. be able to. Further, an appropriate amount of an alcohol or a surfactant may be added to the above alkaline aqueous solution.

[0110]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples. Synthesis Example 1 (Synthesis of photoacid generator [I-3]) t-amylbenzene 60 g, potassium iodate 39.5
g, 81 g of acetic anhydride and 170 ml of dichloromethane were mixed, and 66.8 g of concentrated sulfuric acid was added dropwise over 2 hours while cooling in an ice bath. The reaction solution was stirred as it was for 2 hours, and then stirred at room temperature overnight to complete the reaction. After completion of the reaction, 50 ml of distilled water was added dropwise to the reaction solution while cooling in an ice bath, extraction was performed, the organic layer was washed with water, aqueous sodium bicarbonate and water, and the obtained organic layer was concentrated to give di (t-amylphenyl). ) 40 g of iodonium sulfate was obtained. The target product [I-3] was obtained by subjecting the obtained sulfate and potassium heptadecafluorooctanesulfonate to a salt exchange reaction.

Synthesis Example 2 (Synthesis of photoacid generator [I-6]) 90 g of n-octylphenyl ether, 39.5 g of potassium iodate, 81 g of acetic anhydride, 180 g of dichloromethane
66.8 g of concentrated sulfuric acid while cooling in an ice bath.
Was added dropwise over 2 hours. The reaction solution was stirred as it was for 2 hours, and then stirred at room temperature overnight to complete the reaction. After completion of the reaction, distilled water (50 mL) was added dropwise to the reaction solution while cooling in an ice bath, extraction was performed, and the organic layer was washed with water, aqueous sodium bicarbonate, and water. The obtained organic layer was concentrated, and di (n-octyloxy) was added. 45 g of phenyl) iodonium sulfate were obtained. By subjecting the obtained sulfate and potassium heptadecafluorooctanesulfonate to a salt exchange reaction, the target product [I-6] was obtained.

Synthesis Example 3 (Synthesis of Photoacid Generator [I-9]) Salt exchange between di (t-amylphenyl) iodonium sulfate obtained in Synthesis Example (1) and sodium pentafluorobenzenebenzenesulfonate. [I-9]
Was synthesized.

Synthesis Example 4 (Synthesis of photoacid generator [I-5]) To 40 g of iodobenzene, 91 g of peracetic acid was slowly dropped, and the reaction solution was stirred at 30 ° C for 2 hours. When the white powder came out, it was cooled with ice, the precipitate was collected by filtration, and 38 g of iodosobenzene diacetate was recovered. 50 g of iodosobenzene diacetate, 30 g of octylphenyl ether, 70 g of acetic anhydride, and 725 mL of glacial acetic acid thus obtained were mixed, and concentrated sulfuric acid 8 was cooled in an ice bath.
g was added dropwise over 1 hour. After 1 hour, an aqueous solution in which 31 g of NaBr was dissolved in 150 mL was added dropwise, and 42 g of a precipitated white powder, iodonium bromide salt, was recovered. The obtained iodonium bromide salt and trifluoromethanesulfonate are subjected to salt exchange to obtain the desired product [I-5].
I got

Synthesis Example 5 (Synthesis of photoacid generator [II-3]) 50 g of diphenyl sulfoxide was added to 800 m of mesitylene.
L, and 200 g of aluminum chloride was added thereto, followed by stirring at 80 ° C. for 24 hours. After the completion of the reaction, the reaction solution was slowly poured into 2 L of ice. 400 mL of concentrated hydrochloric acid was added thereto, and the mixture was heated at 70 ° C. for 10 minutes. The reaction solution was cooled to room temperature, washed with ethyl acetate, and filtered. A solution prepared by dissolving 200 g of ammonium iodide in 400 mL of distilled water was added to the filtrate. The precipitated powder was collected by filtration, washed with water, washed with ethyl acetate, dried, and treated with sulfonium iodide 72.
g was obtained. 50 g of the obtained sulfonium iodide was dissolved in 300 mL of methanol, and 31 g of silver oxide was added thereto, followed by stirring for 4 hours. After the reaction solution was filtered, salt exchange was performed with potassium heptadecafluorooctanesulfonate to recover 40 g of the desired product [II-3].

Synthesis Example 6 (Synthesis of Photoacid Generator [II-5]) Synthesis Example (5) was repeated except that pentafluorobenzenesulfonate was used instead of potassium heptadecafluorooctanesulfonate. [II-5] was synthesized in the same manner as in Example (5).

Synthesis Example 7 (Photoacid generator [II-7]) The corresponding sulfonium iodide was synthesized using t-butylphenyl ether instead of mesitylene in Synthesis example (5), and then synthesized. Salt exchange with nonafluorobutanesulfonate is carried out in the same manner as in (5) to obtain the desired compound [II-
7].

Synthesis Example 8 (Synthesis of photoacid generator [II-14]) To 50 g of diphenyl sulfoxide and 45 g of 2,6-xylenol were added methanesulfonic acid / diphosphorus pentoxide (10 /
1) 100 mL of the solution was added. After the fever subsides, 5
Heat at 0 ° C. for 4 hours. After the completion of the reaction, the reaction solution was poured on ice. After washing this aqueous solution with toluene and filtering, an aqueous solution in which 200 g of ammonium iodide was dissolved in 400 mL of distilled water was added, and the precipitated powder was collected by filtration. The obtained residue was washed with water and dried to obtain sulfonium iodide. 50 g of the obtained sulfonium iodide was added to methanol 300 m
L, and 31 g of silver oxide was added thereto, followed by stirring for 4 hours. After the reaction solution was filtered, salt exchange was performed with potassium heptadecafluorooctanesulfonate to recover 43 g of the desired product [II-14].

Synthesis Example 9 (Synthesis of Resin A) A resin having the following structure was synthesized according to Synthesis Example 2 of European Patent Publication No. 0789278. GPC measurement of the obtained resin A showed that the weight average molecular weight (Mw) in terms of standard polystyrene was 33,000. Resin A

[0119]

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Synthesis Example 9 (Synthesis of Resin B) Resin B having the following structure was synthesized according to Synthesis Example 5 of European Patent Publication No. 0789278. GPC of the obtained resin B
As a result of measurement, the weight average molecular weight (Mw) in terms of standard polystyrene was 30,000. Resin B

[0121]

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Synthesis Example 9 (Synthesis of Resin C) 5-norbornene-2,3-dicarboxylic anhydride and
A reaction product of this and cyclopentadiene (50/50 by mole ratio)
A solution of 50) dissolved in dry chlorobenzene was added to a dry chlorobenzene solution containing 0.15 mol% of tungsten hexachloride and 0.3 mol% of triethylamine, followed by stirring. Stir at 30 ° C. for 18 hours, reprecipitate in methanol,
The white acid anhydride resin was removed. Next, this was reacted with glycine to open the acid anhydride site, and then reacted with t-butyl alcohol in the presence of dicyclohexylcarbodiimide to obtain the desired resin C. The composition ratio of each repeating unit (shown below) in the resin C was 18/32/18/32 from NMR measurement. GPC measurement of the obtained resin C showed that the weight average molecular weight (Mw) in terms of standard polyhydroxystyrene was 13,200. Resin C

[0123]

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[Examples] As shown in Table 1, 10 g of each resin synthesized in the above synthesis example and 0.3 g of each photoacid generator were mixed with a solid content of 1%.
After dissolving at a ratio of 4% by weight in 2-heptanone (mixing with 2-hydroxypropionic acid if necessary), 0.1
The solution was filtered through a micrometer micro filter to prepare a positive photoresist composition solution. [Comparative Examples 1 and 2] Instead of the photoacid generator of the above example,
A positive photoresist composition solution was prepared in the same manner as in the above example, except that triphenylsulfonium triflate (B1) shown in the example of paragraph (0132) of JP-A-10-111569 was used.

(Evaluation Test) The obtained positive photoresist composition solution was applied on a silicon wafer by using a spin coater, dried at 130 ° C. for 60 seconds, and about 0.5 μm
Was prepared and exposed to an ArF excimer laser (193 nm). A heat treatment after the exposure was performed at 130 ° C. for 60 seconds, developed with a 2.38% aqueous solution of tetramethylammonium hydroxide, and rinsed with distilled water to obtain a resist pattern profile.

[Stability of composition solution over time]: The prepared positive photoresist composition solution (coating solution) was allowed to stand at 4 ° C. for one week, and then the number of particles was counted using a particle counter manufactured by Rion. [Sensitivity]: Defined as the minimum exposure (mJ / cm ² ) for reproducing a 0.35 μm mask pattern. Table 1 shows the evaluation results.

[0127]

[Table 1]

As is clear from the results shown in Table 1, the positive photoresist composition for deep ultraviolet exposure according to the present invention was
Although satisfactory results were obtained, the positive photoresist composition of Comparative Example was unsatisfactory in the stability over time and sensitivity of the composition solution.

[0129]

As described above, the positive photoresist composition of the present invention is sufficiently suitable especially for light in the wavelength region of 170 nm to 220 nm, can provide high sensitivity and high resolution, and has a good composition. This makes it possible to improve the stability over time of the product solution and has extremely high practicality.

Claims (1)

[Claims] 1. A compound comprising a compound represented by the following formula (I) or (II) which generates a sulfonic acid upon irradiation with actinic rays or radiation, and a repeating unit represented by the following formula (cI) A positive photoresist composition for deep ultraviolet exposure, comprising: a resin which is decomposed by the action of an acid to increase the solubility in alkali. Embedded image In the formula, each of R _{1 to} R ₅ is a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, An alkoxycarbonyl group which may have a substituent, an acyl group which may have a substituent, an acyloxy group which may have a substituent, a nitro group, a halogen atom,
Represents a hydroxyl group and a carboxyl group. a: 1 to 5, b: 1 to 5, l: 1 to 5, m: 0 to 5, n: 0 to 5. However, at least one of R ₁ and R ₂ may have an alkyl group having 5 or more carbon atoms, may have a substituent, may have a cycloalkyl group, may have a substituent. It represents a good alkoxy group, an alkoxycarbonyl group which may have a substituent, an acyl group which may have a substituent, and an acyloxy group which may have a substituent. l + m +
When n = 1, R ₃ has an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, and a substituent. Represents an optionally substituted alkoxycarbonyl group, an optionally substituted acyl group, and an optionally substituted acyloxy group. X represents R—SO ₃ , R represents an aliphatic hydrocarbon group which may have a substituent, or an aromatic hydrocarbon group which may have a substituent. Embedded image In the formula, R _{c1 to} R _c8 may be the same or different, and represent a hydrogen atom, an alkyl group which may have a substituent, a cyclic hydrocarbon group which may have a substituent, a halogen atom, a cyano atom, A group, a group that decomposes under the action of an acid, or —C (＝ O) —Y
And represents _{-AR c9} and -COOR _c11 . p / q: 1 / 9~9 / 1 p + q: 10~100 Y: oxygen atom, a sulfur _{atom, -NH -, - NHSO 2 -} ,
-NHSO 2 divalent linking group selected from _{2 NH-, R c9: -COOH,} -COOR c10 (R c10 definition is synonymous with R _c11 and below lactone structure), - CN, hydroxyl, substituted An optionally substituted alkoxy group, -CO-
NH-R _c11, represents a -CO-NH-SO ₂ -R _c11 or the following lactone structure. R _c11 : an alkyl group which may have a substituent, a cyclic alkyl group which may have a substituent, A: a single bond, an alkylene group, a substituted alkylene group, an ether group, a thioether group, a carbonyl group, an ester A single group selected from the group consisting of a group, an amide group, a sulfonamide group, a urethane group, and a urea group, or a combination of two or more groups. Embedded image R _{29 to} R ₃₆ may be the same or different and represent a hydrogen atom or an alkyl group which may have a substituent. a and b are
Each represents 1 or 2.