JPH05313367A - Positive type radiation sensitive resin composition - Google Patents

Abstract

PURPOSE:To improve pattern shapes, residual film rate, heat resistance and resolution and to obtain sufficient focus latitude by incorporating a specific alkaline-soluble novolak resin, quinone diazide compd. and specific polymer into the above compsn. CONSTITUTION:The alkaline-soluble novolak resin is a resin prepd. by copolymerizing metacresol and paracresol, orthcresol, 2, 3-xyrenol, 3, 4-xyrenol and >=1 kinds of the phenols selected form a group consisting of 2, 3, 5-trimethyl phenols, etc., exclusive of the resins formed by polymerizing only the cresol isomer. Further, the compsn. contains a 1, 2-quinonediazide compd. and the resin expressed by formula. In the formula, R1 and R2 are the same and different and are a hydrogen atom, alkyl group, aryl group, halogen atom, nitro group, alkoxy group or hydrogen group. R3 to R7 may be the same or different and denote a hydrogen atom, alkyl group, alkenyl group or aryl group.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a positive type radiation sensitive resin composition. For more details, ultraviolet rays, far ultraviolet rays X
The present invention relates to a positive-type radiation-sensitive resin composition suitable as a positive-type resist for the production of integrated circuits that is sensitive to radiation such as rays, electron beams, molecular beams, γ-rays, synchrotron radiation, and proton beams.

[0002]

2. Description of the Related Art Positive resists are often used in the manufacture of integrated circuits because a resist pattern having a high resolution can be obtained. However, with the recent high integration of integrated circuits, a resist pattern having a higher resolution can be obtained. There is a demand for a positive type resist capable of forming a film. That is, when a fine resist pattern is formed with a positive resist, when the latent image formed by irradiation with radiation is developed with a developer containing an alkaline aqueous solution, the portion where the irradiation portion is in contact with the wafer (the bottom of the pattern) ) Is required to be rapidly developed.

Further, since the integrated circuit has become complicated, the number of steps for forming a resist pattern of controlled dimensions on a substrate having a large step has been increased in the integrated circuit manufacturing process. Accordingly, there has been a demand for a positive resist having excellent focus tolerance, which can form a resist pattern whose dimension is controlled even if the focus is slightly shifted vertically.

[0004]

However, in the case of the conventional positive type resist, when the distance between the resist patterns to be formed is 0.6 μm or less, the developability in a portion with a small exposure amount such as a fine pattern or a hole. And the pattern shape was insufficient.

Further, as the degree of integration of the integrated circuit is improved,
The wafer etching method is shifting from conventional wet etching with large side etching to dry etching with small side etching. In this dry etching, it is necessary that the resist pattern does not change due to heat at the time of etching. Therefore, the positive resist needs to have heat resistance, whereas the conventional positive resist has sufficient heat resistance. Was difficult.

Further, the conventional positive resist does not have sufficient focus tolerance because when the focus is deviated, the pattern shape is deformed, the developability is deteriorated, and the design line width is deviated. It was Therefore, the object of the present invention is excellent in developability, high sensitivity, pattern shape, residual film rate,
It is an object of the present invention to provide a positive radiation-sensitive resin composition which is excellent in heat resistance and resolution and is particularly suitable as a positive resist having sufficient focus tolerance.

[0007]

According to the present invention, the above objects and advantages of the present invention are (1) paracresol, orthocresol, 2,3-xylenol, 2,5-xylenol, 3,4-xylenol Alkali-soluble novolac resin obtained by polycondensing at least one phenol selected from the group consisting of 3,5-xylenol and 2,3,5-trimethylphenol with metacresol using aldehydes (provided that cresol is used). Except for resins obtained by polycondensing isomers and aldehydes), (2) 1,2
A quinonediazide compound and (3) a structural unit represented by the following structural formula (1)

[0008]

[Chemical 6]

(Wherein R ₁ and R ₂ are the same or different and are a hydrogen atom, an alkyl group, an aryl group, a halogen atom, a nitro group, an alkoxy group or a hydroxyl group,
R ₃ , R ₄ , R ₅ , R ₆ and R ₇ are the same or different and each is a hydrogen atom, an alkyl group, an alkenyl group or an aryl group) and / or a structural unit represented by the following structural formula (2).

[0010]

[Chemical 7]

(Wherein R ₁ and R ₂ are the same as defined in the structural formula (1), and R ₈ , R ₉ and R ₁₀ are the same or different and each is a hydrogen atom, an alkyl group or an aryl group. , And 1 represents a natural number of 10 or less), and a polymer having a polystyrene-equivalent weight average molecular weight of 800 or more is contained in the radiation-sensitive resin composition. Hereinafter, the resin having the structural unit represented by Structural Formula (1) and / or (2) is referred to as “resin (B)”.

Alkali-soluble novolac resin The alkali-soluble novolac resin used in the present invention (hereinafter referred to as "resin (A)") is para-cresol, ortho-cresol, 2,3-xylenol, 2,5-
At least one phenol selected from the group consisting of xylenol, 3,4-xylenol, 3,5-xylenol and 2,3,5-trimethylphenol (hereinafter,
It is an alkali-soluble novolak resin obtained by polycondensing "phenols A") and metacresol with aldehydes. However, the resin obtained by polycondensation using only cresol isomers and aldehydes is not the alkali-soluble novolac resin which is the object of the present invention.

Among the resins (A), preferable combinations of phenols and their preferable composition ratios are as follows. (1) It is composed of meta-cresol and 2,3-xylenol, and the proportion of phenols in the resin is meta-cresol / 2,3-xylenol = 95 to 10
/ 5 to 90 (molar ratio).

(2) Comprised of metacresol, paracresol and 2,3-xylenol,
The ratio of phenols in the resin is meta-cresol / para-cresol / 2,3-xylenol = 90 to 10/5
60 / 5-85 (molar ratio).

(3) Metacresol, 2,3-xylenol and 2,3,5-trimethylphenol, wherein the proportion of phenols in the resin is metacresol / 2,3-xylenol / 2,3,5-Trimethylphenol = 90 to 10/5 to 85/5 to 60 (molar ratio).

(4) Metacresol, 2,3-xylenol and 3,4-xylenol, wherein the proportion of phenols in the resin is metacresol /
2,3-xylenol / 3,4-xylenol = 90-1
Those of 0/5 to 85/5 to 60 (molar ratio). (5) Metacresol and 3,4-xylenol, wherein the proportion of phenols in the resin is metacresol / 3,4-xylenol = 95-50
/ 5 to 50 (molar ratio).

(6) Metacresol, 3,4-xylenol and 2,3,5-trimethylphenol, wherein the proportion of phenols in the resin is metacresol / 3,4-xylenol / 2. 3,3,5-Trimethylphenol = 90 to 20/5 to 50/5 to 60 (molar ratio).

(7) It is composed of meta-cresol and 3,5-xylenol, and the ratio of phenols in the resin is meta-cresol / 3,5-xylenol = 95-30 / 5-70 (mol Ratio).

(8) Metacresol, 3,5-xylenol and 2,3,5-trimethylphenol, wherein the proportion of phenols in the resin is metacresol / 3,5-xylenol / 2,3,5-Trimethylphenol = 90 to 10/5 to 70/5 to 60 (molar ratio).

(9) Metacresol and 2,3,5-trimethylphenol, wherein the proportion of phenols in the resin is metacresol / 2,3,5-
Trimethylphenol = 95-40 / 5-60 (molar ratio).

(10) Metacresol, paracresol and 2,3,5-trimethylphenol, wherein the ratio of phenols in the resin is metacresol / paracresol / 2,3,5- Trimethylphenol = 90 to 10/5 to 60/5 to 60 (molar ratio).

(11) Metacresol, 2,5-xylenol and 3,5-xylenol, wherein the proportion of phenols in the resin is metacresol / 2,5-xylenol / 3,5 -Xylenol = 90
-10/5 to 70/5 to 70 (molar ratio).

(12) Metacresol, 2,5-xylenol, and 2,3,5-trimethylstylphenol, wherein the proportion of phenols in the resin is metacresol / 2,5- Xylenol / 2,3,5-trimethylphenol = 90-10 / 5-70 / 5-60
(Molar ratio).

Examples of aldehydes used here include formaldehyde, benzaldehyde, acetaldehyde, propylaldehyde, phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p. -Hydroxybenzaldehyde, o-chlorobenzaldehyde,
m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-nitrobenzaldehyde, m-nitrobenzaldehyde, p-nitrobenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-
Methylbenzaldehyde, p-ethylbenzaldehyde, pn-butylbenzaldehyde, furfural and the like can be mentioned, and formaldehyde can be particularly preferably used.

Examples of the formaldehyde source include hemiformals such as formalin, trioxane, paraformaldehyde and methylhemiformal, ethylhemiformal, propylhemiformal, butylhemiformal, phenylhemiformal, and the like. Butyl hemiformal can be preferably used. These aldehydes can be used alone or in combination of two or more.

The amount of the above-mentioned aldehydes used is preferably 0.7 to 3 mols per 1 mol of the total amount of phenols,
It is more preferably 0.6 to 1.5 mol. Examples of the catalyst usually used for polycondensation of phenols and aldehydes include acidic catalysts such as hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid and acetic acid. The amount of these acidic catalysts used is usually 1 × 10 ^{−5 to} 5 × 10 ⁻¹ mol per 1 mol of the total amount of phenols and metacresol.

In the polycondensation, water is usually used as the reaction medium, but when the phenols used in the polycondensation do not dissolve in the aqueous solution of the aldehydes and become heterogeneous from the beginning of the reaction, the hydrophilic reaction medium is used. It is also possible to use an organic solvent. Examples of these hydrophilic solvents include alcohols such as methanol, ethanol, propanol and butanol, and cyclic ethers such as tetrahydrofuran and dioxane. The amount of these reaction media used is usually 20 to 1, per 100 parts by weight of the reaction raw material.
It is 00 parts by weight.

The polycondensation temperature can be appropriately adjusted depending on the reactivity of the reaction raw materials, but is usually 10 to 200.
C., preferably 70 to 150.degree. As the polycondensation method, it is possible to adopt a method in which phenols, aldehydes, acidic catalysts, etc. are charged all at once, and a method in which phenols, aldehydes, etc. are added in the presence of an acidic catalyst as the reaction progresses. it can. After completion of the polycondensation, the temperature of the reaction system is generally set to 130 to 23 in order to remove unreacted raw materials, acidic catalyst, reaction medium and the like existing in the system.
The temperature is raised to 0 ° C., the volatile matter is distilled off under reduced pressure at, for example, about 20 to 50 mmHg, and the obtained resin (A) is recovered.

The resin (A) used in the present invention is
Weight average molecular weight in terms of polystyrene by gel permeation chromatography (hereinafter referred to as "Mw")
Is usually 3,000 to 20,000, especially 4,000 to
It is preferably in the range of 15,000. Mw is 20,
When it exceeds 000, it becomes difficult to uniformly apply the composition of the present invention to a wafer, and further the developability and sensitivity are lowered,
If the Mw is less than 3,000, the heat resistance tends to decrease. In order to obtain a resin (A) having a high Mw, for example, the resin (A) recovered after the completion of polycondensation is treated with ethyl cellosolve acetate, dioxane, methanol,
After dissolving in a good solvent such as ethyl acetate, a poor solvent such as water, n-hexane or n-heptane is mixed, and then the resin solution layer to be precipitated is separated to recover the high molecular weight resin (A). ..

In the radiation-sensitive resin composition of the present invention, the above-mentioned resin (A) may be blended alone or in combination of two or more.

1,2-quinonediazide compound In the composition of the present invention, a 1,2-quinonediazide compound is added as a photosensitizer. Examples of such 1,2-quinonediazide compounds include 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, and 1,2-naphthoquinonediazide-5-sulfonic acid ester. Esters, 1,2-naphthoquinonediazide-6-sulfonic acid ester and the like can be mentioned.

Specifically, 1,2-benzoquinonediazide-4-sulfonic acid ester of 1,2-benzoquinonediazide-4-sulfonic acid ester of (poly) hydroxybenzene such as resorcinol, pyrogallol and phlorogricinol, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1 , 2-naphthoquinonediazide-5-sulfonic acid ester or 1,2-naphthoquinonediazide-6-sulfonic acid ester; 2,4-dihydroxyphenylpropyl ketone, 2,4-dihydroxyphenyl-
n-hexyl ketone, 2,4-dihydroxybenzophenone, 2,3,4-trihydroxyphenyl-n-hexyl ketone, 2,3,4-trihydroxybenzophenone,
2,4,6-trihydroxybenzophenone, 2,3,4,
4'-tetrahydroxybenzophenone, 2,2'3,4
-Tetrahydroxybenzophenone, 3'-methoxy-
2,3,4,4'-tetrahydroxybenzophenone, 2,
2 ', 4,4'-tetrahydroxybenzophenone, 2,
2 ', 3,4,6'-pentahydroxybenzophenone,
(Poly) hydroxyphenylalkylketone such as 2,3,3 ', 4,4', 5'-hexahydroxybenzophenone, 2,3 ', 4,4', 5 ', 6-hexahydroxybenzophenone or (poly) 1,2-Benzoquinonediazide-4-sulfonic acid ester of hydroxyphenylarylketone, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-
Sulfonic acid ester or 1,2-naphthoquinonediazide-6-sulfonic acid ester;

Bis (4-hydroxyphenyl) methane,
Bis (2,4-dihydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, 2,2
-Bis (4-hydroxyphenyl) propane, 2,2-
Bis (2,4-dihydroxyphenyl) propane, 2,2
1,2-benzoquinonediazide-4-sulfonic acid ester of bis [(poly) hydroxyphenyl] alkane such as bis (2,3,4-trihydroxyphenyl) propane, 1,2-naphthoquinonediazide-4-sulfonic acid Ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester or 1,2-naphthoquinonediazide-6-
Sulfonate ester;

4,4'-dihydroxytriphenylmethane, 4,4 ', 4 "-trihydroxytriphenylmethane, 2,2', 5,5'-tetramethyl-2", 4,4'-
Trihydroxytriphenylmethane 3,3 ', 5,5'
-Tetramethyl-2 ", 4,4'-trihydroxytriphenylmethane, 4,4 ', 5,5'-tetramethyl-trihydroxytriphenylmethane, 2,2', 5,5'-tetramethyl- 4,4 ', 4 "-trihydroxytriphenylmethane, 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl)
-1-Phenylethane, 1,1-bis (4-hydroxyphenyl) -4- [1- (4-hydroxyphenyl)-
1,2-Benzoquinonediazide-4-sulfonic acid ester of (poly) hydroxytriphenylalkane such as 1-methylethyl] -1-phenylethane, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2
-Naphthoquinonediazide-5-sulfonic acid ester or 1,2-naphthoquinonediazide-6-sulfonic acid ester;

Lauryl 3,5-dihydroxybenzoate,
Phenyl 2,3,4-trihydroxybenzoate 3,4,5
Of lauryl trihydroxybenzoate, propyl 3,4,5-trihydroxybenzoate, phenyl 3,4,5-trihydroxybenzoate, etc. (poly) hydroxybenzoic acid alkyl ester or (poly) hydroxybenzoic acid aryl ester 1,2, -benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4
-Sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester or 1,2-naphthoquinonediazide-6-sulfonic acid ester;

Bis (2,5-dihydroxybenzoyl)
Methane, bis (2,3,4-trihydroxybenzoyl)
Methane, bis (2,4,6-trihydroxybenzoyl)
Methane, p-bis (2,5-dihydroxybenzoyl)
Bis [(poly) hydroxybenzoyl] alkane or bis [(poly) such as benzene, p-bis (2,3,4-trihydroxybenzoyl) benzene, p-bis (2,4,6-trihydroxybenzoyl) benzene Hydroxybenzoyl] benzene 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester or 1,2-naphthoquinonediazide -6-sulfonic acid ester;

(Poly) ethylene such as ethylene glycol-di (3,5-dihydroxybenzoate), polyethylene glycol-di (3,5-dihydroxybenzoate), polyethylene glycol-di (3,4,5-trihydroxybenzoate) Glycol-di [(poly)
Hydroxybenzoate] 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester or 1,2-
Naphthoquinonediazide-6-sulfonic acid ester;

2,4,4-Trimethyl-2 ', 4', 7-trihydroxy-2-phenylflavan, 2,4,4'-trimethyl-2 ', 4', 5 ', 6,7-penta Hydroxy-
1,2-Benzoquinonediazide-4-sulfonic acid ester of polyhydroxyphenylflavan such as 2-phenylflavan, 1,2-naphthoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-5-
Sulfonic acid ester or 1,2-naphthoquinonediazide-6-sulfonic acid ester;

Examples include 1,2-naphthoquinonediazide-4-sulfonic acid ester and 1,2-naphthoquinonediazide-5-sulfonic acid ester of phenolic resin such as phenol novolac resin, cresol novolac resin and polyhydroxystyrene. it can. Further, the 1,2-quinonediazide compounds described in JP-A-1-144,463 and JP-A-1-156,738 relating to the applicant's application can also be used.

Of the above 1,2-quinonediazide compounds, particularly 1,2-naphthoquinonediazide-5-sulfonic acid ester of 2,3,4-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone 1,2-naphthoquinonediazide-5-sulfonic acid ester, 3'-methoxy-2,3,4,4'-tetrahydroxybenzophenone 1,2-naphthoquinonediazide-
1,2-naphthoquinonediazide sulfonic acid ester of polyhydroxybenzophenone such as 5-sulfonic acid ester, 2,2 ′, 5,5′-tetramethyl-2 ″, 4,4 ′
-1,2-naphthoquinonediazide-5-sulfonic acid ester of trihydroxytriphenylmethane, 1,1,1-
1,2-naphthoquinonediazide-5-sulfonic acid ester of tris (4-hydroxyphenyl) ethane, 1,1
-Bis (4-hydroxyphenyl) -1-phenylethane 1,2-naphthoquinonediazide-5-sulfonic acid ester, 1,1-bis (4-hydroxyphenyl) -4
1,2-benzoquinonediazide of (poly) hydroxytriphenylalkane such as 1,2-naphthoquinonediazide-5-sulfonic acid ester of-[1- (4-hydroxyphenyl) -1-methylethyl] -1-phenylethane Sulfonate ester,

1,2 of (poly) hydroxyflavans such as 1,2-naphthoquinonediazide-5-sulfonate of 2,4,4-trimethyl-2 ', 4', 7-trihydroxy-2-phenylflavan -Benzoquinone diazide sulfonate, 1,2-naphthoquinone diazide of phenol / formaldehyde condensed novolak resin-
5-sulfonic acid ester, 1,2-naphthoquinonediazide-5-sulfonic acid ester of m-cresol / formaldehyde condensed novolac resin, 1,2-naphthoquinonediazide-5-sulfonic acid ester of p-cresol / formaldehyde condensed novolac resin, 1,2-naphthoquinonediazide-5-sulfonic acid ester of o-cresol / formaldehyde condensed novolac resin, 1,2-naphthoquinonediazide-5-sulfonic acid ester of m-cresol / p-cresol / formaldehyde condensed novolac resin, etc. Be done.

In the composition of the present invention, the amount of the 1,2-quinonediazide compound is usually 3 to 100 parts by weight, preferably 5 to 50 parts by weight, relative to 100 parts by weight of the resin (A).
Although it is parts by weight, the total amount of 1,2-quinonediazidesulfonyl groups in the composition is usually adjusted to 5 to 25% by weight, preferably 10 to 20% by weight.

Resin (B) Resin (B) has the following structural formula (1)

[0044]

[Chemical 8]

The repeating unit (Y) represented by (the repeating number of the repeating unit (Y) is y) and / or the following structural formula (2)

[0046]

[Chemical 9]

A polymer containing a repeating unit (Z) represented by (the repeating number of the repeating unit (Z) is z) and having an Mw of 800 or more, preferably the repeating unit (Y), Repeating unit (Z) and the following structural formula (3)

[0048]

[Chemical 10]

It is a polymer containing a repeating unit (X) represented by (the repeating number of the repeating unit (X) is x) and having an Mw of 800 or more. Particularly preferred resins (B) are represented by the following relational expressions: 0 ≦ x / x + y + z ≦ 0.8, 0 ≦ y / x + y + z ≦ 1.0, 0 ≦ z / x + y + z ≦ 1.0 and 0.2 ≦ (y + z) / x + y + z. It is a polymer that satisfies all of ≦ 1.0.

The resin (B) can be obtained, for example, by condensing polyhydroxybenzenes and ketones in the presence of an acid catalyst at 20 to 80 ° C. As the polyhydroxybenzenes, compounds having a structure represented by the following structural formula (4) are preferable.

[0051]

[Chemical 11]

(Wherein R ₁ and R ₂ are the same as defined in the structural formula (1)) Examples of such compounds include resorcinol, 2-methylresorcinol, 5-methylresorcinol, 2-ethylresorcinol, 5-ethylresorcinol, 2-chlororesorcinol, 5-chlororesorcinol, 2-bromoresorcinol, 5-
Bromoresorcinol, 2-nitroresorcinol, 5
-Nitroresorcinol, 2-methoxyresorcinol, 5-methoxyresorcinol, 2-ethoxyresorcinol, 5-ethoxyresorcinol, pyrogallol, phloroglicinol, 3,5-dihydroxybenzoic acid, 3,5-dihydroxy-4-methylbenzoic acid, Gallic acid, gallic acid esters and the like can be mentioned as preferable ones.

Of these, resorcinol, 2-methylresorcinol, 5-methylresorcinol, 2-methoxyresorcinol and 5-methoxyresorcinol are particularly preferred. The polyhydroxybenzenes are
They may be used alone or in combination of two or more.

As the ketones, compounds having at least one α hydrogen as shown in the following structural formula (5) are preferable.

[0055]

[Chemical formula 12]

(Wherein R ₁₃ is an alkyl group or an aryl group, and R ₁₄ and R ₁₅ are the same or different and are a hydrogen atom, an alkyl group or an aryl group). Such compounds include, for example, acetone. , Methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 5-ethyl-3-heptanone,
2-octanone, 3-octanone, methyl isobutyl ketone, 4-phenyl-2-pentanone, methylcyclohexyl ketone, cyclopentanone, cyclobutanone, cyclohexanone, 2-methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone,
Examples thereof include cycloheptanone, cyclooctanone, camphor, menthone, methylbenzyl ketone, anisylacetone, acetophenone and acetylnaphthalene.

Of these, acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 3-hexanone, 2-heptanone, methyl isobutyl ketone, cyclohexanone, 2-methylcyclohexanone, 3-methylcyclohexanone, 4-methyl Cyclohexanone, cycloheptanone and cyclooctanone are particularly preferred. The above ketones may be used alone or in combination of two or more.

The resin (B) used in the present invention is
The hydroxyflavan derivative represented by the following structural formula (6) or structural formula (7) can be obtained alone or by polycondensing phenols with aldehydes and / or ketones.

[0059]

[Chemical 13]

[0060]

[Chemical 14]

(Wherein R _{1 to} R ₁₀ and l are the same as defined in the structural formulas (1) and (2))

Examples of the phenols include phenols used in the synthesis of the resin (A), phenols represented by the above structural formula (4), phenol, 1-naphthol,
2-naphthol, catechol and the like are also used. Also,
As the aldehydes, those used in the synthesis of the resin (A) can be used. Furthermore, the ketones are not particularly limited, and ketones having no α-hydrogen can also be used.

Examples of the acidic catalyst used in the polycondensation synthesis of the resin (B) include hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid, acetic acid and paratoluenesulfonic acid. The amount of these acidic catalysts used is preferably 10 ⁻¹ to 10 ² mol per 1 mol of the polyhydroxybenzene derivative.

In the polycondensation, the reaction medium is usually the aldehydes and ketones used in the reaction, but a hydrophilic solvent may be added as the reaction medium. Examples of these hydrophilic solvents include alcohols such as methanol, ethanol and propanol, and cyclic ethers such as tetrahydrofuran and dioxane. The amount of these reaction media used is usually 20 to 1,000 parts by weight per 100 parts by weight of the reaction raw material. Water may be added to adjust the molecular weight of the resin (B) produced. The temperature of the polycondensation can be appropriately adjusted depending on the reactivity of the reaction raw material, but is usually 10
-100 ° C, preferably 20-80 ° C.

After completion of polycondensation, in order to remove unreacted raw materials, acidic catalyst, reaction medium and the like existing in the system, the temperature of the reaction system is set in the range of 130 ° C. to 23 ° C. as in the case of the resin (A).
The resin (B) thus obtained may be recovered by elevating the temperature to 0 ° C. and distilling off the volatile matter under reduced pressure, for example, at about 20 to 50 mmHg, or a suitable amount of the resin (B) produced can be dissolved. The resin (B) may be recovered by dissolving it in a hydrophilic solvent, pouring it into a large amount of water for reprecipitation, filtering the precipitate, washing with pure water several times, and drying.

The resin (B) used in the present invention is
Mw is usually 800 to 8,000, preferably 1.00
It is preferably in the range of 0 to 5,000. Mw is 8,
When it exceeds 000, it becomes difficult to uniformly apply the composition of the present invention to a wafer, and further the developability and sensitivity tend to be remarkably lowered, and when Mw is less than 800, the pattern shape is deteriorated and the focus tolerance is lowered. Tend to do. The resin (B) may be used alone or in combination of 2
You may mix | blend with the combination of 1 or more types.

Various compounding agents In the composition of the present invention, various compounding agents such as a sensitizer, a surfactant and a dissolution accelerator can be compounded. The sensitizer is added to improve the sensitivity of the resist. Examples of such a sensitizer include 2H-pyrido- (3,2-b) -1,4-oxazine-3 ( 4H)
-Ones, 10H-pyrido- (3,2-b)-(1,4)
-Benzothiazines, urazoles, hydantoins,
Examples thereof include barbituric acids, glycine anhydrides, 1-hydroxybenzotriazoles, alloxans, maleimides and the like. The compounding amount of these sensitizers is usually 50 parts by weight or less, preferably 30 parts by weight or less, relative to 100 parts by weight of the resin (A).

The surfactant is added to improve the coatability and developability of the composition. Examples of such a surfactant include polyoxyethylene lauryl ether and polyoxyethylene oleyl ether. Nonionic surfactants such as polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate, F-top EF3
01, EF303, EF352 (trade name, manufactured by Shin-Akita Kasei Co., Ltd.), Megafax F171, F172, F173
(Product name, manufactured by Dainippon Ink and Chemicals, Inc.), Florard FC43
0, FC431 (trade name, manufactured by Sumitomo 3M Ltd.), Asahi Guard AG710, Surflon S-382, SC-1
01, SC-102, SC-103, SC-104, S
Fluorochemical surfactants such as C-105 and SC-106 (trade name, manufactured by Asahi Glass Co., Ltd.), organosiloxane polymers
KP341 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) and acrylic acid-based or methacrylic acid-based (co) polymer polyflow N
Nos. 75 and No. 95 (trade name, manufactured by Kyoeisha Oil and Fat Chemical Co., Ltd.). The content of these surfactants is usually 2 parts by weight or less per 100 parts by weight of the solid content of the composition.

The dissolution accelerator is used for the purpose of promoting the alkali solubility of the composition of the present invention, and examples thereof include low molecular weight phenol compounds. The low molecular weight phenol compound used here has a benzene ring number of 2 to
A phenol compound of about 6 is preferably used and is not particularly limited. The blending amount of the low molecular weight phenol compound is usually 50 parts by weight or less with respect to 100 parts by weight of the resin (A).

Further, in the composition of the present invention, a dye or a pigment can be blended in order to visualize the latent image in the radiation-irradiated portion and reduce the influence of halation during radiation irradiation, and improve the adhesiveness. In order to do so, an adhesion aid can be added. Further, if necessary, a storage stabilizer, a defoaming agent and the like can be added.

Preparation of Composition and Pattern Formation The composition of the present invention comprises the above-mentioned resin (A) and 1,2-
It is prepared by dissolving the quinonediazide compound, the resin (B), and the above-mentioned various compounding agents in a solvent so that the solid content concentration becomes 20 to 40% by weight, and filtering with a filter having a pore size of about 0.2 μm. ..

Examples of the solvent used at this time include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether. Acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclohexanone, 2-heptanone, 3-heptanone, 4-
Heptanone, ethyl 2-hydroxypropionate, 2-
Ethyl hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, 2-hydroxy-
Methyl 3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, propyl acetate, butyl acetate Etc. can be used. These organic solvents are used alone or in combination of two or more. Furthermore, N-methylformamide, N,
N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethylether, dihexylether, acetonylacetone, isophorone, caproic acid, caprylic acid, It is also possible to add a high boiling point solvent such as 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosolve acetate. ..

The composition of the present invention is applied to a silicon wafer or a wafer coated with aluminum, for example, by spin coating, flow coating, roll coating or the like to form a radiation sensitive layer, and a predetermined mask pattern is formed. A pattern is formed by irradiating the radiation-sensitive layer with radiation through the solution and developing with a developing solution.

When the composition of the present invention is used as a positive resist, the composition is applied onto a wafer, prebaked and irradiated with radiation, and then 70 to 1 is applied.
The effect of the present invention can be further improved by performing an operation of heating at 40 ° C. and then performing development.

Developer The developer of the composition of the present invention is, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n. -Propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, pyrrole, piperidine, 1,8-diazabicyclo- (5.4.0) -7
-Undecene, 1,5-diazabicyclo- (4.3.0)
An alkaline aqueous solution obtained by dissolving an alkaline compound such as -5-nonane to a concentration of usually 1 to 10% by weight, preferably 2 to 5% by weight is used. In addition, a water-soluble organic solvent, for example, alcohols such as methanol and ethanol and a surfactant may be added to the developer in an appropriate amount. When developing is performed using a developing solution composed of such an alkaline aqueous solution, generally, rinsing with water is subsequently performed.

[0076]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. The measurement of Mw and the evaluation of the resist in the examples were performed by the following methods.

Mw: Tosoh GPC column (G200
0H _XL 2 this, one G3000H _XL, G4000H _XL
1 column), a flow rate of 1.0 ml / min, an elution solvent of tetrahydrofuran, and a column temperature of 40 ° C. were used for analysis by a gel permeation chromatography method using monodisperse polystyrene as a standard.

Sensitivity: Nikon NSR-1505i6A
The exposure time is converted by a reduction projection exposure device (lens numerical aperture: 0.45) and exposure is performed using an i-line having a wavelength of 365 nm, or alternatively, a Nikon NSR-1505i7A reduction projection exposure device (lens aperture) is used. Number: 0.50) and change the exposure time by using the Nikon NSR-150564D reduction projection exposure machine (lens numerical aperture 0.45). Exposure, using a g-line with a wavelength of 436 nm, then using a 2.4% by weight aqueous solution of tetramethylammonium hydroxide as a developing solution, developing at 25 ° C. for 60 seconds, rinsing with water, drying and drying on a wafer. Exposure time for forming a resist pattern on a 0.5 μm line-and-space pattern (1L1S) with a width of 1: 1 (hereinafter referred to as “optimum exposure time”). "Between").

Resolution: The dimension of the smallest resist pattern resolved when exposed at the optimum exposure time was measured. Residual film rate: The thickness of the pattern after development at the optimum exposure time was divided by the thickness of the resist film before development, and this value was multiplied by 100 and expressed as a unit of%. Developability: The degree of scum and residual development was examined.

Pattern shape: Using a scanning electron microscope,
The lower side A and the upper side B of the rectangular cross section after development of the resist pattern of 0.6 μm were measured, and when 0.85 ≦ B / A ≦ 1, it was determined that the pattern shape was good. However,
If the pattern shape is skirted or has a reverse taper shape, it is not judged to be good even if B / A falls within the above range.

Focus Tolerance: In the 1L1S pattern, a Nikon NSR-1505i7A reduction projection exposure machine (lens numerical aperture of 0.50) was used to measure i at a wavelength of 365 nm.
The focus position was varied when the line was exposed for the optimum exposure time, and the range of the focus range where the pattern shape continued to be good was measured based on the above definition.

Synthesis Example 1 m-cresol 45.4 g (0.42 mol) 2,3-xylenol 36.7 g (0.21 mol) 2,3,5-trimethylphenol 9.53 g (0.07 mol) 37 Weight% formaldehyde solution 55.4 g (formaldehyde 0.682 mol) Oxalic acid dihydrate 1.76 g (0.014 mol) Water 33.8 g and dioxane 206 g were charged into an autoclave, immersed in an oil bath, and the internal temperature was adjusted. 1
While maintaining at 30 ° C., polycondensation was carried out for 8 hours while stirring, and after the reaction, the temperature was returned to room temperature and the contents were taken out into a beaker.
After this was separated into two layers, the lower layer was taken out, concentrated, dehydrated and dried to recover the resin. This resin is resin (A1)
And

Synthesis Example 2 m-cresol 53.0 g (0.49 mol) 3,4-xylenol 25.7 g (0.21 mol) 37% by weight formaldehyde solution 49.7 g (formaldehyde 0.61 mol) oxalic acid 2 Hydrate 4.41 g (0.035 mol) 57.2 g of water and 265 g of dioxane were charged into an autoclave, polycondensation was carried out for 8 hours in the same manner as in Synthesis Example 1, and the resin was recovered. This resin is referred to as resin (A2).

Synthesis Example 3 m-cresol 60.6 g (0.56 mol) 2,3-xylenol 8.55 g (0.07 mol) 2,3,5-trimethylphenol 9.54 g (0.07 mol) 37 Weight% formaldehyde solution 54.0 g (formaldehyde 0.67 mol) Oxalic acid dihydrate 4.41 g (0.035 mol) Water 54.5 g and dioxane 265 g were charged in an autoclave, and the same as in Synthesis Example 1 for 6 hours. Polycondensation was performed and the resin was recovered. This resin is referred to as resin (A3).

Synthesis Example 4 m-cresol 60.6 g (0.56 mol) 3,4-xylenol 8.55 g (0.07 mol) 2,3-xylenol 8.55 g (0.07 mol) 37% by weight formaldehyde Solution 51.1 g (formaldehyde 0.63 mol) Oxalic acid dihydrate 4.41 g (0.035 mol) Water 55.7 g and dioxane 262 g were charged in an autoclave, and polycondensation was carried out for 6 hours in the same manner as in Synthesis Example 1. Done and the resin was recovered. This resin is referred to as resin (A4).

Synthesis Example 5 m-cresol 45.4 g (0.42 mol) 2,3-xylenol 25.7 g (0.21 mol) 3,4-xylenol 8.55 g (0.07 mol) 37% by weight formaldehyde Solution 56.8 g (formaldehyde 0.70 mol) Oxalic acid dihydrate 4.41 g (0.035 mol) Water 53.8 g and dioxane 269 g were charged into an autoclave, and polycondensation was carried out for 8 hours in the same manner as in Synthesis Example 1. Done and the resin was recovered. This resin is referred to as resin (A5).

Synthesis Example 6 A flask equipped with a stirrer, a condenser and a thermometer was charged with m-cresol 60.6 g (0.56 mol) 3,4-xylenol 7.33 g (0.060 mol) 37% by weight formaldehyde solution. 73.0 g (formaldehyde 0.90 mol) and oxalic acid dihydrate 1.26 g (0.010 mol) were charged, immersed in an oil bath and the internal temperature was kept at 100 ° C for 60 minutes while stirring. After polycondensation, 15.1 g (0.14 mol) of m-cresol and 29.3 g (0.24 mol) of 3,4-xylenol were added, and polycondensation was further carried out for 120 minutes. Next, the temperature of the oil bath was raised to 180 ° C., and at the same time, the pressure inside the flask was reduced to 30 to 50 mmHg to remove water, oxalic acid, unreacted monomers and the like. Then, the molten resin was returned to room temperature and recovered. This resin is referred to as resin (A6).

Synthesis Example 7 The resin (A6) was dissolved in methyl 3-methoxypropionate to a solid content of 30% by weight, and then 0.4 times toluene and 0.4 times the weight of the resin solution was dissolved. 8-fold hexane was added, and the mixture was stirred and left to stand. After separating into two layers by standing, the resin solution layer (lower layer) was taken out, concentrated, dehydrated and dried to recover the resin. This resin is referred to as resin (A7).

Synthesis Example 8 m-cresol 60.6 g (0.56 mol) p-cresol 10.8 g (0.10 mol) 3,4-xylenol 4.89 g (0.040 mol) 37% by weight formaldehyde solution 73 0.0g (formaldehyde 0.90 mol) and oxalic acid dihydrate 1.26 g (0.010 mol) were placed in the same flask as in Synthesis Example 6, and the internal temperature was 100 ° C.
After polycondensation was carried out for 60 minutes while stirring at 150 ° C., m-cresol (15.1 g, 0.14 mol) and 3,4-xylenol (19.5 g, 0.16 mol) were added, and the mixture was further added for 150 minutes. Condensation was performed. Then, the resin was recovered by the same operation as in Synthesis Example 6. This resin is referred to as resin (A8).

Synthesis Example 9 The resin (A8) was dissolved in ethyl cellosolve acetate so that the solid content was 30% by weight, and 0.5 times the weight of this resin solution was added to hexane and the mixture was stirred and left to stand. did. After separating into two layers by standing, the resin solution layer (lower layer) was taken out, concentrated and dried to recover the resin. This resin is referred to as resin (A9).

Synthesis Example 10 A flask equipped with a stirrer, a cooling tube and a thermometer was charged with 40 g of resorcinol 55.0 g (0.50 mol) water and 40 g of 36 wt% hydrochloric acid aqueous solution, and stirred with 150 g of acetone at an internal temperature. 5
The solution was added dropwise over 2 hours while maintaining the temperature below 0 ° C. afterwards,
The reaction was carried out for 2 hours while maintaining the reflux state at 75 ° C.

After the reaction was completed, the internal temperature was returned to room temperature and 1,4
-300 g of dioxane were added. Then, the reaction solution was poured into 3 liters of pure water that was vigorously stirred to deposit a pale yellow precipitate. The precipitate was separated by filtration, dissolved again in 300 g of acetone, and reprecipitated in pure water by the same operation as above. The precipitate was separated by filtration, washed with pure water several times, and then dried under reduced pressure to recover the resin. This resin is
1). The structural unit of (B1) is shown below.

[0093]

[Chemical 15]

Synthesis Example 11 2-Methylresorcinol 62.0 g (0.50 mol) Water 40 g and 36 wt% hydrochloric acid aqueous solution 40 g were charged in the same flask as in Synthesis Example 10, and acetone 15 was added.
0 g was added dropwise in the same manner as in Synthesis Example 10, the reaction was carried out under reflux with stirring for 3 hours, and then the resin was recovered by the same operation as in Synthesis Example 10. This resin is referred to as resin (B2).
The structural unit of (B2) is shown below.

[0095]

[Chemical 16]

Synthesis Example 12 2,4,4-Trimethyl-2 ', 4', 7-trihydroxy-2-phenylflavane 56.8 g (0.2 mol) Resorcinol 33.0 g (0.3 mol) Acetone 100 g And 40 g of water were charged in the same flask as in Synthesis Example 10, and 40 g of 36 wt% hydrochloric acid aqueous solution was added dropwise over 1 hour while keeping the internal temperature at 50 ° C. or lower. Then, the reaction was carried out for 1 hour while maintaining the reflux state at 75 ° C., and then the resin was recovered by the same operation as in Synthesis Example 10. This resin is called resin (B3). The structural unit of (B3) is shown below.

[0097]

[Chemical 17]

Examples 1 to 12 and Comparative Examples 1 to 2 Various resins (A) and resins (B) synthesized in the above synthesis examples, various low molecular weight compounds (C) and quinonediazide compounds (D) described below. Using a solvent and a solvent, these were mixed to form a uniform solution, which was then filtered through a membrane filter having a pore size of 0.2 μm to prepare a composition solution of the present invention.

The following compounds were used as the compound (C). (C1): 1,1,3-tris (2,5-dimethyl-4-
Hydroxyphenyl) butane (C2): 1,1,3-tris (2,5-dimethyl-4-)
Hydroxyphenyl) -3-phenylpropane (C3): 1,1-bis (4-hydroxyphenyl)-
1-phenylethane (C4): 1,1,1-tris (4-hydroxyphenyl) ethane (C5): 1,1-bis (2,5-dimethyl-4-hydroxyphenyl) -1- (2-hydroxy Phenyl) methane

The following were used as the quinonediazide compound (D). (D1): Condensation product of 1 mol of 2,3,4,4'-tetrahydroxybenzophenone and 3 mol of 1,2-naphthoquinonediazide-5-sulfonyl chloride (D2): 2,3,4,4'-tetrahydroxy Condensation product of 1 mol of benzophenone and 4 mol of 1,2-naphthoquinonediazide-5-sulfonyl chloride (D3): 1 mol of 1,1,1-tris (4-hydroxyphenyl) ethane and 1,2-naphthoquinonediazide-5
-Condensation product of 1 mol of sulfonyl chloride (D4): 1,1-bis (4-hydroxyphenyl)-
Condensation product of 1 mol of 4- [1- (4-hydroxyphenyl) -1-methylethyl] -1-phenylethane and 2 mol of 1,2-naphthoquinonediazide-5-sulfonyl chloride (D5): 1,1-bis (4-hydroxyphenyl)-
Condensate of 4- [1- (4-hydroxyphenyl) -1-methylethyl] -1-phenylethane (1 mol) and 1,2-naphthoquinonediazide-5-sulfonyl chloride (2.5 mol) (D6): 1,1 -Bis (4-hydroxyphenyl)-
Condensation product of 1 mol of 4- [1- (4-hydroxyphenyl) -1-methylethyl] -1-phenylethane and 2 mol of 1,2-naphthoquinonediazide-4-sulfonyl chloride (D7): 1,1-bis (4-hydroxyphenyl)-
Condensate of 1 mole of 4- [1- (4-hydroxyphenyl) -1-methylethyl] -1-phenylethane and 2.5 moles of 1,2-naphthoquinonediazide-4-sulfonyl chloride (D8): 2,4, Condensate of 1 mole of 4-trimethyl-2 ′, 4 ′, 7-trihydroxy-2-phenylflavan and 2.7 moles of 1,2-naphthoquinonediazide-5-sulfonyl chloride (D9): m-cresol novolac resin ( Mw = 3,
000) 1,2-naphthoquinonediazide-5-sulfonyl chloride condensate (average condensation rate 25%)

The types of solvents used are as follows. (Α): Ethyl cellosolve acetate (β): Methyl 2-hydroxypropionate (γ): Methyl 3-methoxypropionate (δ): Ethyl 3-ethoxypropionate The addition amount of each component is shown in Table 1.

The obtained solution was applied on a silicon wafer having a silicon oxide film using a spinner, and then prebaked on a hot plate at 90 ° C. for 2 minutes to form a resist film having a thickness of 1.2 μm. , Wavelength 436 nm (g line) or wavelength 365 as described above through the reticle.
nm (i-line) exposure and 11 on hot plate
Post exposure bake (PE
After performing B), developing, rinsing and drying, the resist film was evaluated for sensitivity, resolution, residual film rate, developability, heat resistance, pattern shape and focus tolerance. The measurement results are shown in Table 1, Table 2 and Table 3 together with the resins used.

[0103]

[Table 1]

[0104]

[Table 2]

[0105]

[Table 3]

[0106]

The radiation-sensitive resin composition of the present invention comprises an alkali-soluble novolak resin obtained from a combination of specific phenols, a resin having a specific structural unit, and 1.
In connection with the use of the 2-quinonediazide compound, a positive resist having excellent developability, high sensitivity, excellent pattern shape, residual film rate, heat resistance and resolution, and particularly sufficient focus tolerance. Can be suitably used as.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Takao Miura 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (2)

[Claims] 1. (1) Paracresol, orthocresol, 2,3-xylenol, 2,5-xylenol, 3,
4-xylenol, 3,5-xylenol and 2,3,
Alkali-soluble novolac resin obtained by polycondensing at least one phenol selected from the group consisting of 5-trimethylphenol and meta-cresol with aldehydes (provided by polycondensing cresol isomers with aldehydes) (2) 1,2-quinonediazide compounds and (3) structural units represented by the following structural formula (1): (In the formula, R ₁ and R ₂ are the same or different and each is a hydrogen atom, an alkyl group, an aryl group, a halogen atom, a nitro group, an alkoxy group or a hydroxyl group, and R ₃ , R ₄ ,
R ₅ , R ₆ and R ₇ are the same or different and each is a hydrogen atom, an alkyl group, an alkenyl group or an aryl group) and / or a structural unit represented by the following structural formula (2): (In the formula, R ₁ and R ₂ are the same as defined in the structural formula (1), R ₈ , R ₉ and R ₁₀ are the same or different and each is a hydrogen atom, an alkyl group or an aryl group, and l
Represents a natural number of 10 or less), and contains a polymer having a polystyrene-equivalent weight average molecular weight of 800 or more, which is a positive radiation-sensitive resin composition. 2. The polymer according to claim 1 (3) has the following structural formula (3): The repeating unit (X) represented by (the repeating number of the repeating unit (X) is x), and the following structural formula (1): A repeating unit (Y) represented by (the repeating number of the repeating unit (Y) is y), and the following structural formula (2): A polymer comprising a repeating unit (Z) represented by the formula (wherein the number of repeating units (Z) is z), wherein: 0 ≦ x / x + y + z ≦ 0.8, 0 ≦ y / x + y + z The radiation-sensitive resin composition according to claim 1, which is a polymer satisfying all of ≤1.0, 0≤z / x + y + z≤1.0 and 0.2≤ (y + z) /x+y+z≤1.0.