JP3209058B2 - Positive resist composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive resist composition which gives a positive image in response to radiation such as near ultraviolet rays or far ultraviolet rays (including excimer lasers and the like).

[0002]

2. Description of the Related Art It is generally known that a compound having a phenolic hydroxyl group is converted into a quinonediazidesulfonic acid ester and used as a photosensitive agent in a resist composition for semiconductor fine processing. That is, when a composition containing a compound having a quinonediazide group and an alkali-soluble resin is applied to a metal substrate and irradiated with light of 300 to 500 nm, the quinonediazide group is decomposed to generate a carboxyl group, and the alkali-insoluble state is changed. The composition is used as a positive resist by utilizing the alkali-soluble state. Such a positive resist has a feature of being superior in resolving power as compared with a negative resist, and thus is used for manufacturing various integrated circuits for semiconductors.

[0003] In recent years, integrated circuits in the semiconductor industry have been miniaturized in accordance with high integration, and submicron pattern formation has now been required. Among them, the lithography process occupies an important position in the production of integrated circuits, and even higher resolution (higher γ value) is required for positive resists.

[0004] With respect to resist materials containing a quinonediazide compound and an alkali-soluble resin, many proposals have been made for combinations of components. For example, Japanese Patent Application Laid-Open No. 1-189644 (= USP 5,153,096) describes that a triphenylmethane-based compound having at least two phenolic hydroxyl groups converted to a quinonediazidesulfonic acid ester is used as a photosensitive agent. . However, even if such a known photosensitive agent is used, there is a limit as a resist for submicron lithography for ultra-fine processing for manufacturing an ultra-high integrated circuit at present. Therefore, various studies have been conducted to improve the resist performance such as sensitivity, resolution, and heat resistance. For example, JP-A-6-167805 (= EP-A-573,056) discloses four or more resists. It is disclosed that a compound having a phenol nucleus is converted to a quinonediazidesulfonic acid ester and used as a photosensitizer.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a positive resist which balances various resist properties such as high sensitivity, high resolution, good profile, good focus tolerance, good heat resistance and little development residue. It is an object of the present invention to provide a mold resist composition.

[0006]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the use of a quinonediazidesulfonic acid ester of a phenolic compound having a specific structure having a paracresol skeleton at both ends as a photosensitizer makes it a known product. As a result, they have found that a composition having a better balance of various resist properties can be obtained, and the present invention has been completed.

That is, the present invention provides a compound represented by the general formula (I)

[0008]

Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ ,
^{R 7, R 8, R 9} , R 10, R 11, R 12, R 13, R 14, R 15
And R ¹⁶ are independently of each other hydrogen, hydroxyl,
6 represents alkyl or phenyl, and n represents 0 or 1). The present invention also provides a positive resist composition containing a sensitizer containing a quinonediazidesulfonic acid ester of a phenolic compound represented by the formula (1) and an alkali-soluble resin.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the general formula (I), R ¹ , R
^{2, R 3, R 4,} R 5, R 6, R 7, R 8, R 9,
R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ have the meanings as defined above, but in particular R ¹ ,
At least one of R ² , R ³ and R ⁴ , R ⁵ , R ⁶ ,
At least one of R ⁷ and R ⁸ , at least one of R ⁹ , R ¹⁰ , R ¹¹ and R ¹² , and R ¹³ , R ¹⁴ , R ¹⁵
And at least one of R ¹⁶ is preferably a hydroxyl group. Further, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R
^{7, R 8, R 9,} R 10, R 11, R 12, R 13, R 14, R 15
And the remainder of R ¹⁶ is preferably hydrogen or alkyl. Alkyl is particularly preferably methyl.

The phenol compound represented by the general formula (I) is, for example, a compound represented by the general formula (II)

[0012]

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ ,
R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ ,
R ¹⁵ , R ¹⁶ and n are as defined above)
It can be produced by reacting a polyhydric alcohol with paracresol in the presence of an acid catalyst such as paratoluenesulfonic acid, hydrochloric acid or sulfuric acid. The dihydric alcohol represented by the general formula (II) is, for example, a compound represented by the general formula (III)

[0014]

(Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ ,
R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ ,
R ¹⁵ , R ¹⁶ and n represent the above-mentioned meanings) by reacting the compound with formaldehyde in the presence of an alkali catalyst such as sodium hydroxide. The compound represented by the general formula (III) can be used as it is as long as it is commercially available.Alternatively, the compound of the monobenzene nucleus is sequentially reacted by reacting with formaldehyde starting from the compound of the monobenzene nucleus. They can also be combined and combined.

Alternatively, the phenolic compound of the general formula (I) may be a compound of the formula (IV)

[0017]

2-hydroxymethyl-4 having the structure of
Starting from the monomethylol form of methylphenol, i.e. paracresol, in the presence of an acid catalyst such as paratoluenesulfonic acid or sulfuric acid,
Can be produced by condensing with the compound represented by

As a further alternative, a phenolic compound represented by the general formula (I) can be produced by reacting a compound represented by the general formula (III) with paracresol and formaldehyde.

The phenol compound of the general formula (I) obtained by these reactions can be obtained by crystallization from an aromatic solvent such as benzene, toluene, xylene or the like, preferably toluene. The phenol compound is preferably dissolved in a solvent having a solubility in water of 9 g / 100 g or less and then washed and separated with water to reduce the metal content. Here, that the solubility in water is 9 g / 100 g or less means that the maximum amount soluble in 100 g of water at 20 ° C. is 9 g or less. The solvent used here preferably has a solubility of the phenol compound of the general formula (I) at 20 ° C. of 1 g / 100 g or more. Examples of such a solvent include ethyl acetate and n-acetic acid.
Examples thereof include acetates such as butyl and isoamyl acetate, ketones such as methyl isobutyl ketone and 2-heptanone, and among them, ethyl acetate is preferably used. The solution containing the phenol compound of the general formula (I) in which the amount of metal has been reduced can be further added with an aromatic solvent to crystallize the target product. The aromatic solvent used here can be benzene, toluene, xylene and the like, and preferably toluene is used.

The phenol compound of the general formula (I) thus obtained is converted to a quinonediazidesulfonic acid ester to be used as a photosensitizer. In the esterification, 1,2
-Various sulfonic acid derivatives having a quinonediazide skeleton, for example, quinonediazide sulfonyl halides such as 1,2-benzoquinonediazide-4-sulfonyl halide and 1,2-naphthoquinonediazide-4- or -5-sulfonyl halide can be used. ,Preferably,
1,2-Naphthoquinonediazide-4- or -5-sulfonyl halide is used. The halogen constituting the sulfonyl halide can be, for example, chlorine or bromine, but is usually preferably chlorine, and therefore 1,2-naphthoquinonediazide-4- or -5-.
Sulfonyl chloride is preferably used as the esterifying agent. Also, 1,2-naphthoquinonediazide-4-
Sulfonyl halide and 1,2-naphthoquinonediazide
Mixtures of 5-sulfonyl halides can also be used. In the esterification reaction, the quinonediazidosulfonyl halide is generally used in a molar ratio of 1.2 or more to the number of phenolic hydroxyl groups in the general formula (I) with respect to the phenol compound of the general formula (I).

This reaction is usually carried out in the presence of a dehydrohalogenating agent. Examples of the dehydrohalogenating agent include generally basic compounds such as sodium carbonate, inorganic bases such as sodium hydrogencarbonate, ethylamine, ethanolamine, diethylamine, diethanolamine, triethylamine, N, N-dimethylaniline, N, N-diethyl. Examples include amines such as aniline. The dehydrohalogenating agent is used usually in a molar ratio of 1 to 1.5, preferably 1.05 to 1.2, based on quinonediazide sulfonyl halide.

The esterification reaction is usually performed in a solvent. Examples of the reaction solvent include ethers, lactones, and aliphatic ketones, among which dioxolane,
It is preferred to choose from 1,4-dioxane, tetrahydrofuran, γ-butyrolactone, acetone and 2-heptanone. These can be used alone or in combination of two or more, and 1,4-dioxane is particularly preferable. The reaction solvent is used in an amount of usually 2 to 6 times by weight, preferably 3 to 5 times by weight, based on the total amount of the phenol compound of the general formula (I) and quinonediazide sulfonyl halide. This esterification reaction sufficiently proceeds at about normal temperature under normal pressure.
A temperature in the range of ３０30 ° C. is employed and is performed for about 2 to 10 hours.

After completion of the reaction, neutralize with an acid such as acetic acid,
After filtering the solid, the filtrate is mixed with a dilute aqueous acid solution, for example, an aqueous acetic acid solution having a concentration of about 0.1 to 2% by weight.
The desired ester is deposited. By filtering, washing and drying this, the ester can be taken out.

In this esterification reaction, although it depends on the molar ratio of the quinonediazidosulfonyl halide used,
Usually, it is obtained as a mixture of two or more of those in which a part of the phenolic hydroxyl groups in the general formula (I) are esterified and those in which all of them are esterified. This mixture can usually be used as it is as a photosensitive agent. Of course, quinonediazidesulfonic acid esters of two or more phenol compounds contained in the general formula (I) can be used in combination.

The photosensitizer thus esterified is combined with an alkali-soluble resin to form a positive resist composition sensitive to radiation such as near-ultraviolet rays or far-ultraviolet rays (including excimer lasers and the like).

If necessary, a quinonediazidesulfonic acid ester of another phenolic compound can be used in combination as a photosensitizer. Specific examples of the quinonediazidesulfonic acid ester used in combination are disclosed in JP-A-5-204148.
Compounds described in JP-A-5-323597 (= EP-A
-570,884), JP-A-6-167805 (=
EP-A-573,056), a compound of the following formula (VI)

[0028]

Wherein one of R ²¹ and R ²² is —OX ⁴
And R ²³ , R ²⁴ and R ²⁵ independently of R ²¹ and R ²² are independently hydrogen, alkyl having 6 or less carbons, cycloalkyl having 6 or less carbons, alkenyl having 6 or less carbons, R ²⁶ and R ²⁷ each independently represent hydrogen, alkyl having 6 or less carbons or alkenyl having 6 or less carbons,
Or both are joined together at the terminus to form a cycloalkane ring having 6 or less carbon atoms together with the carbon atom to which they are attached; ^one of X ¹ , X ² , X ³ and X ⁴ represents quinonediazidosulfonyl; Each independently represents hydrogen or quinonediazidosulfonyl) [Japanese Patent Application No. 7-58826, filed by the present applicant earlier (= Japanese Patent Application Laid-Open No. 8-99952).
Described in Japanese Unexamined Patent Publication (KOKAI) No. 2000-131).

In the present invention, when such other quinonediazide sulfonic acid ester is used, the sensitizer is contained in the range of 10 to 50% by weight based on the total solid content in the resist composition. Is preferred.

The alkali-soluble resin constituting the positive resist composition is preferably a novolak resin obtained by condensing a compound having at least one phenolic hydroxyl group with an aldehyde in the presence of an acid catalyst. The type is not particularly limited, and various types used in the field of resist can be used. Examples of the phenolic compound as a raw material of the novolak resin include, for example, meta-cresol, para-cresol, ortho-cresol,
2,5-xylenol, 3,5-xylenol, 3,4
-Xylenol, 2,3,5-trimethylphenol,
2-t-butyl-5-methylphenol, t-butylhydroquinone, and the like. Examples of the aldehyde that is another raw material of the novolak resin include formaldehyde, acetaldehyde, benzaldehyde, glyoxal, and salicylaldehyde. Particularly, formaldehyde is industrially mass-produced as an aqueous solution of about 37% by weight and is preferably used.

Novolak resins can be obtained by condensing one or more of these phenolic compounds and one or more of aldehydes in the presence of an acid catalyst. As the acid catalyst, an organic acid, an inorganic acid, a divalent metal salt or the like is used, and specific examples thereof include oxalic acid, acetic acid, p-toluenesulfonic acid, hydrochloric acid, sulfuric acid, phosphoric acid, and zinc acetate. The condensation reaction can be performed according to a conventional method.
It is performed for about 30 hours. The reaction may be performed in a bulk or in a suitable solvent.

The obtained novolak resin is subjected to, for example, fractionation for the purpose of reducing the development residue of the resist, and the gel permeation chromatography (GP)
C) In the pattern (using a detector of UV 254 nm), the area ratio of the component having a molecular weight of 900 or less in terms of polystyrene is 25% or less with respect to the entire pattern area excluding the pattern area of the unreacted phenolic compound. 2
It is preferable to keep it at 0% or less. When performing separation, a novolak resin is mixed with a good solvent, for example, an alcohol such as methanol or ethanol, a ketone such as acetone, methyl ethyl ketone or methyl isobutyl ketone, an ethylene glycol ether such as ethyl cellosolve, or an ethylene such as ethyl cellosolve acetate. Glycol ether ester, a method of dissolving in a cyclic ether such as tetrahydrofuran and the like, and pouring this solution into water to precipitate a high molecular weight component, or
A method of mixing with a poor solvent such as pentane, hexane or heptane to carry out liquid separation can be employed.

It is also effective to add an alkali-soluble compound having a molecular weight of 900 or less to the novolak resin having a high molecular weight component by performing such a separation operation. Molecular weight 90
The alkali-soluble compound having a molecular weight of 0 or less preferably has at least two phenolic hydroxyl groups in the molecular structure. For example, JP-A-2-75955 (= EP-A-358,871)
And those described in JP-A-2-2-2560. When an alkali-soluble compound having a molecular weight of 900 or less is used, 3 to 40 based on the total solid content in the resist composition.
It is preferable to contain it in the range of weight%.

The preparation of the resist solution is carried out using a photosensitive agent and an alkali-soluble resin, or if necessary, a molecular weight of 90 or more.
It is carried out by mixing and dissolving 0 or less alkali-soluble compounds in a solvent. The solvent used here preferably has an appropriate drying rate and gives a uniform and smooth coating film after the solvent evaporates. Examples of such a solvent include glycol ether esters such as propylene glycol monomethyl ether acetate and ethyl cellosolve acetate, methyl cellosolve acetate, ethyl pyruvate, n-amyl acetate, esters such as ethyl lactate, and 2-heptanone. Ketones, cyclic esters such as γ-butyrolactone, etc.
Examples thereof include those described in Japanese Unexamined Patent Application Publication No. 6-64, Japanese Unexamined Patent Application Publication No. 4-362645, and Japanese Unexamined Patent Application Publication No. 4-367863. As a solvent, each compound alone,
Alternatively, two or more kinds can be used in combination.

The resist composition thus obtained may further contain a small amount of a resin other than the novolak resin, a dye, or the like, if necessary.

[0037]

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In the examples, percentages and parts representing contents or amounts used are by weight unless otherwise specified.

Synthesis Example 1 (1) Dimethylolation of 2,6-bis (4-hydroxy-2,5-dimethylbenzyl) -4-methylphenol

In a three-liter four-necked flask, 2,6-
Bis (4-hydroxy-2,5-dimethylbenzyl)-
263.6 g of 4-methylphenol, sodium hydroxide 6
7.2 g, 1169.3 g of water and 10 of tetrahydrofuran
7.5 g was charged and dissolved, and the temperature was adjusted to 40 ° C. 340.9 g of 37% formalin was added dropwise thereto over 1 hour, and the mixture was further stirred at the same temperature for 2 hours. After the reaction, 90
The solution was neutralized with 134.4 g of a 30% aqueous acetic acid solution and cooled to 25 ° C.
The precipitated crystals were filtered and rinsed with 1000 g of ion-exchanged water. The obtained filtrate was dried under reduced pressure at 45 ° C. overnight to obtain 265 g of 2,6-bis (4-hydroxy-3-hydroxymethyl-2,5-dimethylbenzyl) -4-methylphenol. 80% purity.

Mass Spectrometry: MS 436 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.95 (s, 3H); 2.05 (s, 6H); 2.10 (s, 6H); 3.78 (s, 4H); 4.65 (s, 4H); 5.23 (brs, 2H); 6.31 (s, 2H); 6.70 (s, 2H); 8.18 (brs, 1H); 8.60 (brs, 2H).

(2) 2,6-bis [4-hydroxy-3-
Production of (2-hydroxy-5-methylbenzyl) -2,5-dimethylbenzyl] -4-methylphenol (referred to as Compound 1)

A 1-liter four-neck flask was charged with 1.90 g of paratoluenesulfonic acid, 86.5 g of paracresol and 176.83 g of toluene, and the temperature was adjusted to 30 ° C. There, 80% pure 2,6- obtained in the above (1).
Bis (4-hydroxy-3-hydroxymethyl-2,5
-Dimethylbenzyl) -4-methylphenol 21.83
g was divided into 10 portions and charged over 1 hour and 30 minutes. Thereafter, the mixture was further reacted for 3 hours. After completion of the reaction, the mixture was filtered and rinsed with 200 g of toluene. The obtained filtrate is washed with toluene 2
In a mixture of 00 g and 400 g of ethyl acetate was added and dissolved at 60 ° C., and 400 g of ion-exchanged water was added, followed by stirring and separation. Thereafter, 400 g of a 1% oxalic acid aqueous solution was charged, stirred, and separated to separate metals.
Next, after washing with 400 g of ion exchange water four times,
The oil layer was concentrated. 200 g of toluene was added to the concentrated mass, cooled to 20 ° C., filtered, and rinsed with 200 g of toluene. The obtained filtrate was dried under reduced pressure at 45 ° C. overnight to obtain 22.87 g of Compound 1. Quantitative purity 94.6%.

Mass spectrometry: MS 616 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.88 (s, 6H); 1.95 (s, 3H); 2.03 (s, 6H); 2.13 (s, 6H); 3.78 (s, 4H); 3.88 (s, 4H); 6.28 (s, 2H); 6.32 (s, 2H); 6.68 (d, J = 8.2 Hz, 2H); 6.70 (s, 2H); 6.74 (d, J = 8.2 Hz, 2H); 7.95 (brs, 2H); 8.12 (brs, 1H); 9.20 (brs, 2H).

(3) Quinonediazidesulfonic acid esterification of compound 1

Compound 1 was placed in a 100 ml four-necked flask.
1.85 g, 1,2-naphthoquinonediazido-5-sulfonyl chloride (1.61 g) and 1,4-dioxane (17.33 g) were charged and the temperature was adjusted to 25 ° C. 0.73 g of triethylamine was added dropwise thereto over 1 hour, and the mixture was further reacted for 3 hours. After completion of the reaction, the mixture was neutralized with 0.18 g of acetic acid and filtered. The filtrate was poured into a mixed solution of 0.8 g of acetic acid and 80 g of ion-exchanged water and stirred for 1 hour, and the precipitated crystals were filtered and washed. The obtained filtrate is heated at 45 ° C.
And dried under reduced pressure all day and night to obtain 3.23 g of photosensitizer A.

Mass spectrometry value of main component: MS 1080 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.70 (s, 6H); 1.95 (s, 3H); 2.05 (s, 6H); 2.13 (s, 6H); 3.75 (s, 4H); 3.86 (s, 4H); 6.22 (s, 2H); 6.40 (s, 2H); 6.65 (d, J = 8.2 Hz, 2H); 6.72 (s, 2H); 6.88 (d, J = 8.2 Hz, 2H); 7.42 (d, J = 7.9 Hz, 2H); 7.64 (t, J = 7.9 Hz, 2H); 7.75 (d, J = 7.9 Hz, 2H); 8.04 ( s, 2H); 8.15 (s, 1H); 8.25 (d, J = 7.9 Hz, 2H); 8.62 (d, J = 7.9 Hz, 2H).

Synthesis Example 2 (1) Dimethylolation of 2,3,5-trimethylphenol

In a 2 liter four-necked flask, add 2,3,5
136.19 g of trimethylphenol, 48.0 g of sodium hydroxide and 480 g of water were charged and dissolved,
Temperature. There are 486.91g of 37% formalin in 1
The mixture was added dropwise over time, and then stirred at the same temperature for another 3 hours. After completion of the reaction, the mixture was neutralized with 180.15 g of a 90% aqueous acetic acid solution, cooled to 25 ° C., and filtered. The filtrate was extracted with 1000 g of ethyl acetate, and the ethyl acetate layer was washed with water and concentrated. The concentrated mass was charged with 500 g of toluene, cooled to 20 ° C., filtered, and rinsed with 400 g of toluene. The obtained filtrate was dried under reduced pressure at 45 ° C. for 24 hours.
100 g of 2,4-bis (hydroxymethyl) -3,5,6-trimethylphenol was obtained. 90% purity.

Mass spectrometry: MS 196 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 2.06 (s, 3H); 2.19 (s, 3H); 2.21 (s, 3H); 4.41 (d, J = 8.2 Hz) , 2H); 4.43 (t, J = 8.2 Hz, 1H); 4.62 (s, 2H); 5.41 (brs, 1H); 8.80 (brs, 1H).

(2) 2,4-bis (4-hydroxy-2,
Production of 5-dimethylbenzyl) -3,5,6-trimethylphenol

5.88 sulfuric acid was placed in a 5-liter four-necked flask.
g, 2,5-xylenol 293.2 g and methanol 293.2 g, and the mixture was adjusted to 30 ° C. There, 90% pure 2,4-bis (hydroxymethyl) -3,5,
117.75 g of 6-trimethylphenol was added over 1 hour in 10 portions and then reacted at the same temperature for another 2 hours. After the completion of the reaction, 500 g of toluene and 1000 g of ethyl acetate were charged, and 1000 g of ion-exchanged water was further added.
Was stirred and then separated. Thereafter, 1000 g of a 1% oxalic acid aqueous solution was charged into the oil layer, stirred, and separated to separate metals. Next, ion exchange water 10
After washing with 00 g four times, the oil layer was concentrated. To the concentrated mass was added 500 g of toluene, cooled to 20 ° C., filtered, and rinsed with 200 g of toluene. The filtrate was dissolved in 500 g of ethyl acetate, and the oil layer was concentrated. 500 g of toluene is charged to the concentrated mass, and 2
After cooling to 0 ° C, the mixture was filtered and 200 g of toluene was further added.
Rinsed. The obtained filtrate was dried under reduced pressure at 45 ° C. overnight to obtain 98.6 g of 2,4-bis (4-hydroxy-2,5-dimethylbenzyl) -3,5,6-trimethylphenol. Quantitative purity 99.38%.

Mass Spectrometry: MS 404 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.81 (s, 3H); 1.89 (s, 6H); 2.00 (s, 3H); 2.12 (s, 3H); 2.22 (s, 6H); 3.68 (s, 2H); 3.78 (s, 2H); 6.08 (s, 1H); 6.15 (s, 1H); 6.58 (s, 1H); 6.60 (s, 1H); 7.80 ( s, 1H); 8.80 (s, 1H); 8.85 (s, 1H).

(3) 2,4-bis (4-hydroxy-2,
Dimethylolation of (5-dimethylbenzyl) -3,5,6-trimethylphenol

In a 500 ml four-necked flask, 2,4-bis (4-hydroxy-2,5-dimethylbenzyl) -3,5,6-trimethyl having a purity of 99.38% obtained in the above (2) was added. Phenol 44.5 g, sodium hydroxide 14.40
g, 144 g of water and 14.40 g of tetrahydrofuran were charged and dissolved, and the temperature was adjusted to 40 ° C. Thereto, 48.69 g of 37% formalin was added dropwise over 1 hour, and the mixture was further stirred at the same temperature for 3 hours. After the completion of the reaction, the mixture was neutralized with 18.02 g of a 90% aqueous acetic acid solution, cooled to 25 ° C., and filtered. The filtrate was dissolved in a mixed solution of 100 g of ethyl acetate and 14.40 g of tetrahydrofuran, washed with water, and then the oil layer was concentrated. 100 g of toluene is charged to the concentrated mass,
After cooling to 20 ° C., the mixture was filtered and rinsed with 100 g of toluene. The obtained filtrate was dried under reduced pressure at 45 ° C for 24 hours, to give 36.8 g of 2,4-bis (4-hydroxy-3-hydroxymethyl-2,5-dimethylbenzyl) -3,5,6-trimethylphenol. Obtained. Purity 75%.

Mass Spectrometry: MS 464 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.78 (s, 3H); 1.93 (s, 6H); 2.01 (s, 3H); 2.13 (s, 3H); 2.26 (s, 6H); 3.71 (s, 2H); 3.81 (s, 2H); 4.67 (s, 4H); 5.22 (brs, 2H); 6.08 (s, 1H); 6.13 (s, 1H); 7.78 ( brs, 1H); 8.46 (brs, 1H); 8.47 (brs, 1H).

(4) 2,4-bis [4-hydroxy-3-
Production of (2-hydroxy-5-methylbenzyl) -2,5-dimethylbenzyl] -3,5,6-trimethylphenol (referred to as compound 2)

In a 200 ml four-necked flask, 0.57 g of paratoluenesulfonic acid, 38.93 g of paracresol and 38.93 g of toluene were charged, and the temperature was adjusted to 30 ° C.
There, 13.94 g of 75% pure 2,4-bis (4-hydroxy-3-hydroxymethyl-2,5-dimethylbenzyl) -3,5,6-trimethylphenol obtained in the above (3) was added. It is divided into 10 and put in over 1 hour and 30 minutes,
Thereafter, the reaction was further performed at the same temperature for 2 hours. After the reaction,
The precipitated crystals were filtered and rinsed with 100 g of toluene. The filtrate was dissolved in a mixed solution of 100 g of toluene and 200 g of ethyl acetate at 60 ° C., and 200 g of ion-exchanged water was further stirred and separated. 200 g of a 1% oxalic acid aqueous solution was added to the oil layer, and the mixture was stirred and separated to remove metal. Next, washing with 200 g of ion-exchanged water was performed four times, and then the oil layer was concentrated. 100 g of toluene is added to the concentrated mass, and
After cooling, the mixture was filtered and rinsed with 100 g of toluene.
The obtained filtrate was dried under reduced pressure at 45 ° C for 24 hours to obtain 10.3 g of Compound 2. Quantitative purity 94.9%.

Mass spectrometry: MS 644 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.81 (s, 3H); 2.01 (s, 12H); 2.11 (s, 6H); 2.16 (s, 3H); 2.29 (s, 3H); 3.72 (s, 2H); 3.82 (s,
2H); 3.90 (s, 4H); 6.10 (s, 1H); 6.18 (s, 1H); 6.38
(s, 1H); 6.40 (s, 1H); 6.70 (d, J = 7.1 Hz, 2H); 6.
75 (d, J = 7.1 Hz, 2H); 7.93 (brs, 3H); 9.24 (brs,
2H).

(5) Quinonediazidesulfonic acid esterification of compound 2

Compound 2 was placed in a 100 ml four-necked flask.
0.97 g, 0.81 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 8.87 g of 1,4-dioxane were charged and the temperature was adjusted to 25 ° C. Thereto, 0.36 g of triethylamine was added dropwise over 1 hour, and the mixture was further reacted for 3 hours. After completion of the reaction, the mixture was neutralized with 0.09 g of acetic acid and filtered. The filtrate was added to a mixed solution of 0.5 g of acetic acid and 50 g of ion-exchanged water and stirred for 1 hour, and the precipitated crystals were filtered and washed. The obtained filtrate is subjected to 45
Drying under reduced pressure at ℃ for 24 hours gave 1.65 g of Photosensitive Agent B.

Mass spectrometry value of main component: MS 1108 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.79 (s, 3H); 1.95 (s, 12H); 2.00 (s, 3H); 2.04 (s, 6H); 2.17 (s, 3H); 3.70 (s, 2H); 3.80 (s, 2H); 3.87 (s, 2H); 3.90 (s, 2H); 6.10 (s, 1H); 6.17 (s, 1H ); 6.40 (s, 1H); 6.45 (s, 1H); 6.65 (d, J = 7.8 Hz, 2H); 6.90 (d, J = 7.8 Hz, 2H); 7.44 (d, J = 7.4 Hz, 2H) ); 7.69 (t, J = 7.2 Hz, 2H); 7.76 (d, J = 7.4 Hz, 2H); 7.91 (brs, 3H); 8.26 (d, J = 7.2 Hz, 2H); 8.61 (d, J = 7.2 Hz, 2H).

Synthesis Example 3 (1) Dimethylolation of 3,4-xylenol

In a 2-liter four-necked flask, 3,4-
Xylenol (122.17 g), sodium hydroxide (48 g) and water (480 g) were charged, and the mixture was stirred at 40.degree.
486.9 g of% formalin was added dropwise over 1 hour, and the mixture was further reacted for 1 hour. After the completion of the reaction, 180.2 g of acetic acid
Was charged, and the precipitated crystals were filtered and rinsed with ion-exchanged water. The obtained filtrate was dried to obtain 139.8 g of 2,6-dihydroxymethyl-3,4-dimethylphenol.
Obtained. LC purity 95.4%.

Mass spectrometry: MS 182 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 2.18 (s, 6H); 4.68 (s, 2H); 4.84 (s, 2H); 3.80 (brs, 2H); 6.89 (s, 1H); 9.12 (brs, 1H).

(2) 2,6-bis (4-hydroxy-2,
Production of 5-dimethylbenzyl) -3,4-dimethylphenol

In a 1-liter four-necked flask, add 4.90 sulfuric acid.
g, 244.3 g of 2,5-xylenol and 244.3 g of a 60% aqueous methanol solution, and the temperature was adjusted to 30 ° C., and the 2,6-dihydroxymethyl having a purity of 95.4% obtained in the above (1) was added thereto. 91.1 g of -3,4-dimethylphenol
Was divided into 10 portions and charged over 1 hour, and then reacted for 2 hours. After completion of the reaction, 50 g of toluene and 500 g of ethyl acetate were charged and stirred, and then separated. Thereafter, 500 g of a 1% oxalic acid aqueous solution was charged and stirred,
Metal separation was performed by liquid separation. Next, washing with 500 g of ion-exchanged water was performed four times, and then the oil layer was concentrated. The concentrated mass was charged with 500 g of toluene, cooled to 20 ° C., filtered, and rinsed with 200 g of toluene.
The filtrate was dissolved in 500 g of ethyl acetate and then concentrated. The concentrated mass was charged with 500 g of toluene, cooled to 20 ° C., filtered, and rinsed with 200 g of toluene.
The obtained filtrate was dried under reduced pressure at 45 ° C for 24 hours.
-Bis (4-hydroxy-2,5-dimethylbenzyl)
139.8 g of -3,4-dimethylphenol was obtained. Quantitative purity 95.7%.

Mass spectrometry: MS 390 ¹ H-NMR
(Dimethyl sulfoxide) δ (ppm): 1.88 (s, 6H); 2.01 (s, 3H); 2.06 (s, 3H); 2.08 (s, 3H); 2.27 (s, 3H); 3.70 (s, 2H) ; 3.80 (s, 2H); 6.17 (s, 1H); 6.48 (s, 1H); 6.59 (s, 2H); 6.68 (s, 1H); 7.85 (s, 1H); 8.80 (s, 1H); 8.88 (s, 1H).

(3) 2,6-bis (4-hydroxy-2,
Dimethylolation of (5-dimethylbenzyl) -3,4-dimethylphenol

The 95.7% pure 2,6-bis (4-hydroxy-2,5-dimethylbenzyl) -3,4-dimethylphenol 5 obtained in the above (2) was placed in a 100 ml four-necked flask. .86 g, sodium hydroxide 2.16 g, water 21.6
g and 2.16 g of tetrahydrofuran were charged and dissolved, and the temperature was adjusted to 40 ° C. Thereto, 7.30 g of 37% formalin was added dropwise over 1 hour, and the mixture was further stirred for 1 hour. After completion of the reaction, neutralize with 3 g of 90% acetic acid aqueous solution,
After cooling to 5 ° C., it was filtered. This filtrate was dissolved in a mixed solution of 100 g of ethyl acetate and 100 g of toluene, washed with water, and then the oil layer was concentrated. Toluene 100 in concentrated mass
g was cooled to 20 ° C., filtered, and then rinsed with 100 g of toluene. The obtained filtrate was dried under reduced pressure at 45 ° C. overnight to give 2,6-bis (4-hydroxy-3).
-Hydroxymethyl-2,5-dimethylbenzyl)-
6.76 g of 3,4-dimethylphenol were obtained. Purity 65
%.

Mass spectrometry: MS 450

(4) 2,6-bis [4-hydroxy-3-
Production of (2-hydroxy-5-methylbenzyl) -2,5-dimethylbenzyl) -3,4-dimethylphenol (referred to as compound 3)

A 100 ml four-necked flask was charged with 0.10 g of paratoluenesulfonic acid, 6.49 g of paracresol and 6.49 g of toluene, and the temperature was adjusted to 30 ° C. There, 65% pure 2,6-bis (4) obtained in the above (3) was added.
-Hydroxy-3-hydroxymethyl-2,5-dimethylbenzyl) -3,4-dimethylphenol (2.55 g) was added in 10 portions over 1 hour, and the mixture was further reacted for 1 hour. After the reaction, 10 g of toluene and 2 g of ethyl acetate were added.
0 g was charged at 60 ° C., and 20 g of ion-exchanged water was further charged, stirred and separated. Thereafter, 20 g of a 1% oxalic acid aqueous solution was charged and stirred, and liquid separation was performed by liquid separation. Next, washing with 20 g of ion-exchanged water was performed four times, and then the oil layer was concentrated. The concentrated mass was separated by silica gel column chromatography to give compound 3 in 0.2.
g was obtained. Quantitative purity 96.1%.

Mass spectrometry: MS 630

(5) Quinonediazidesulfonic acid esterification of compound 3

Compound 3 was placed in a 100 ml four-necked flask.
And 0.12 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 1.20 g of 1,4-dioxane, and the mixture was adjusted to 25 ° C., and 0.05 g of triethylamine was added thereto for 1 hour. Then, the reaction was further performed for 3 hours. After completion of the reaction, the mixture was neutralized with 0.02 g of acetic acid and filtered. The filtrate was poured into a mixture of 0.1 g of acetic acid and 10 g of ion-exchanged water, stirred for 1 hour, filtered, and washed. The obtained filtrate was dried under reduced pressure at 45 ° C for 24 hours to obtain 0.21 g of photosensitizer C.

Mass spectrometry value of main component: MS 109
4

Synthesis Example 4 (1) 4,4'-methylenebis [2- (2-hydroxy-
5-methylbenzyl) -3,6-dimethylphenol]
Manufacturing of

A 500 ml three-necked flask was charged with 144.16 g of paracresol, 81.557 g of toluene and 0.43 g of 36% hydrochloric acid, and the temperature was adjusted to 50 ° C.
18.98 g of methylenebis (2-hydroxymethyl-3,6-dimethylphenol) was dividedly charged over 1 hour,
The mixture was further stirred for 3 hours. Thereafter, the mixture was cooled and filtered, and the obtained filtrate was dissolved in 269 g of ethyl acetate, and distilled water 4
After washing with 7.82 g, the washing with distilled water was repeated four more times, and then the oil layer was concentrated. 107.5 g of toluene was added to the concentrate, and the precipitated crystals were filtered and rinsed twice with 44.54 g of toluene. The obtained wet cake was dried under reduced pressure at 45 ° C for 24 hours to obtain 4,4′-methylenebis [2- (2-hydroxy-
5-methylbenzyl) -3,6-dimethylphenol]
13.45 g was obtained.

[0079]

Mass spectrometry value: MS 497 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.92 (s, 6H); 2.02 (s, 6H); 2.09 (s, 6H); 3.68 (s, 2H); 3.88 (s, 4H); 6.33 (s, 2H); 6.48 (s, 2H); 6.70 (m, 4H); 7.94 (brs, 2H); 9.22 (brs, 2H).

(2) 4,4'-methylenebis [2- (2-
Hydroxy-5-methylbenzyl) -3,6-dimethylphenol]

In a 4 liter four-necked flask, add 4,4 ′
-Methylenebis [2- (2-hydroxy-5-methylbenzyl) -3,6-dimethylphenol] 49.66 g,
9.60 g of sodium hydroxide, 167.1 g of water and 16.7 g of tetrahydrofuran were charged and dissolved, and the temperature was adjusted to 40 ° C. 48.7 g of 37% formalin was added dropwise thereto over 1 hour, and the mixture was further stirred for 5 hours. After the reaction, 9
Neutralized with 19.2 g of 0% acetic acid aqueous solution and cooled to 25 ° C.
Thereafter, the mixture was filtered and rinsed with 100 g of ion-exchanged water. The obtained filtrate was dried under reduced pressure at 45 ° C. for 24 hours to obtain 4,4 ′.
48.2 g of -methylenebis [2- (2-hydroxy-3-hydroxymethyl-5-methylbenzyl) -3,6-dimethylphenol] were obtained. 84% purity.

Mass spectrometry: MS 556 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.92 (s, 6H); 2.05 (s, 6H); 2.10 (s, 6H); 3.69 (s, 2H); 3.94 (s, 4H); 4.55 (d, J = 7.2 Hz, 4H); 5.27 (t, J = 7.2 Hz, 2H); 6.27 (s, 2H); 6.60 (s, 2H); 6.85 (s, 2H) ; 8.06 (s, 2H); 8.45 (s, 2H).

(3) 4,4'-methylenebis [2- {2-
Production of hydroxy-3- (2-hydroxy-5-methylbenzyl) -5-methylbenzyl {-3,6-dimethylphenol] (referred to as compound 4)

A 1-liter four-necked flask was charged with 1.14 g of paratoluenesulfonic acid, 17.30 g of paracresol and 34.60 g of toluene, and the temperature was adjusted to 30 ° C.
There, 11.13 g of 84% pure 4,4'-methylenebis [2- (2-hydroxy-3-hydroxymethyl-5-methylbenzyl) -3,6-dimethylphenol] obtained in (2) above. Was divided into 10 portions and charged over 1 hour and 30 minutes, and reacted for further 3 hours. After the completion of the reaction, the mixture was filtered and rinsed with 100 g of toluene. The filtrate was dissolved in a mixed liquid of 100 g of toluene and 200 g of ethyl acetate at 60 ° C., and 200 g of ion-exchanged water was added, followed by stirring and liquid separation. Then, 1% oxalic acid aqueous solution 20
0 g was charged, stirred, and separated to carry out demetallization. Next, washing with 200 g of ion-exchanged water was performed four times, and then the oil layer was concentrated. Toluene 100 in concentrated mass
g, cooled to 20 ° C., filtered,
Rinse with 0 g. The obtained filtrate was dried under reduced pressure at 45 ° C. overnight to obtain 9.89 g of compound 4. Quantitative purity 9
4.7%.

Mass spectrometry: MS 736 ¹ H-NMR (dimethyl sulfoxide) δ (ppm): 1.93 (s, 6H); 1.98 (s, 6H); 2.09 (s, 6H); 2.14 (s, 6H); 3.68 (s, 2H); 3.78 (s, 4H); 3.94 (s, 4H); 6.20 (s, 2H); 6.48 (s, 2H); 6.56 (s, 2H); 6.68 (d, J = 7.4 Hz, 2H); 6.80 (m, 4H); 8.05 (brs, 2H); 8.30 (brs, 2H); 9.40
(brs, 2H).

(4) Quinonediazidesulfonic acid esterification of compound 4

Compound 4 was placed in a 100 ml four-necked flask.
Was charged, and 0.27 g of 1,2-naphthoquinonediazide-5-sulfonyl chloride and 3.19 g of 1,4-dioxane were charged and the temperature was adjusted to 25 ° C. Thereto, 0.12 g of triethylamine was added dropwise over 1 hour, and the mixture was further reacted for 3 hours. After the completion of the reaction, the mixture was neutralized with 0.03 g of acetic acid and filtered. The filtrate was added to a mixed solution of 0.3 g of acetic acid and 30 g of ion-exchanged water and stirred for 1 hour, and the precipitated crystals were filtered and washed. The obtained filtrate was dried under reduced pressure at 45 ° C. for 24 hours to obtain 0.57 g of photosensitizer D.

Mass spectrometry value of main component: MS 1200

Compounds 1 to 4 obtained in the above Synthesis Examples 1 to 4
No. 4 (before quinonediazidesulfonic acid esterification) has the following structures, respectively.

[0091]

Reference Example 1: Production of novolak resin In a four-necked flask, 148.5 parts of meta-cresol, 121.5 parts of para-cresol, and 252 of methyl isobutyl ketone
Parts, 10% oxalic acid aqueous solution 37.0 parts and 90% acetic acid aqueous solution 84.8 parts were charged, and 129.5 parts of 37% formalin was added dropwise over 40 minutes while heating and stirring in an oil bath at 100 ° C. The reaction was continued for another 15 hours. Next, it was washed with water and dehydrated to obtain 466 parts of a methyl isobutyl ketone solution containing 42.3% of a novolak resin. The weight average molecular weight in terms of polystyrene measured by GPC was 4,300. 450 parts of this solution was charged into a separable flask with a bottom, 909.6 parts of methyl isobutyl ketone and 996.1 parts of n-heptane were added, and the mixture was stirred at 60 ° C. for 30 minutes, allowed to stand, and separated. . In the lower layer mass obtained by liquid separation,
380 parts of 2-heptanone was added, and methyl isobutyl ketone and n-heptane were removed by an evaporator to obtain a 2-heptanone solution of a novolak resin. GP
The weight average molecular weight in terms of polystyrene by C was 9000, and the area ratio in the range of 900 or less in terms of polystyrene was 14% with respect to the entire pattern area.

Examples 1 to 4 15 parts of a 2-heptanone solution of the novolak resin obtained in Reference Example 1 in terms of solids content, and 1,3-bis [1
3.9 parts of-(2,4-dihydroxyphenyl) -1-methylethyl] benzene, 5 parts of the photosensitive agent shown in Table 1, and 1,2,3-trihydroxy-4- as another photosensitive agent.
1 part of a condensate of (4-hydroxy-2,5-dimethylbenzyl) benzene and 1,2-naphthoquinonediazide-5-sulfonyl chloride in a molar ratio of 1: 4,
Heptanone was mixed and dissolved so that 2-heptanone was 50 parts in total. This solution was filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist solution.

The silicon wafer cleaned by a conventional method is
The resist solution was applied using a spin coater so that the film thickness after drying was 1.1 μm, and was applied on a hot plate for 90 μm.
Bake at ℃ for 1 minute. Next, a reduced projection exposure device having an exposure wavelength of 365 nm (i-line) [Nikon Corporation, NS
R 1755i 7A, NA = 0.5], and the exposure was changed stepwise. Next, the wafer was baked on a hot plate at 110 ° C. for 1 minute. Use this as a developer “SOP”
D "(product of Sumitomo Chemical Co., Ltd.) for 1 minute to obtain a positive pattern. Each positive pattern was evaluated as follows, and the results are shown in Table 1.

Effective sensitivity: Display was performed at an exposure amount at which a 0.5 μm line-and-space pattern became 1: 1. Resolution: At the exposure amount (effective sensitivity) at which the line-and-space pattern becomes 1: 1, the dimensions of the line-and-space pattern separated without film loss were measured with a scanning electron microscope. Focus (depth of focus): 0.4μ in effective sensitivity
m The width of the focal point where the line-and-space pattern separates without film loss was measured with a scanning electron microscope. Scum: The presence of scum (development residue) was observed with a scanning electron microscope. γ value: normalized film thickness with respect to logarithm of exposure amount (= remaining film thickness /
(Initial film thickness) was plotted, the slope θ was obtained, and tan θ was defined as a γ value.

Further, among the respective positive type patterns,
When the profile (cross-sectional shape) of the 0.45 μm line-and-space pattern in the effective sensitivity was observed with a scanning electron microscope, all the patterns were cut vertically.

[0097]

[Table 1] 例 Example Photosensitive agent resist performance Effective sensitivity Resolution Depth of focus Scum γ value (msec) (μm) (μm) １ 1 A 230 0.375 1.5 None 6.82 2 B 250 0.35 1.5 None 7.61 3 C 240 0.375 1.5 None 6.92 4 D 380 0.375 1.5 None 5.92 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━

[0098]

The positive resist composition according to the present invention comprises:
High sensitivity and high resolution (γ
Value), good profile, good focus tolerance,
Resist properties such as small development residue are balanced.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-159990 (JP, A) JP-A-7-159989 (JP, A) JP-A-6-167805 (JP, A) JP-A 8- 95240 (JP, A) International Publication 96/20430 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03F 7/022

Claims (7)

(57) [Claims] 1. A compound of the general formula (I) (Wherein , R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R
⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ each independently represent hydrogen, a hydroxyl group, alkyl having 1 to 6 carbon atoms or phenyl, and n represents 0 or 1. A positive resist composition comprising a sensitizer containing a quinonediazidesulfonic acid ester of a phenolic compound represented by the formula (1) and an alkali-soluble resin. 2. At least one of R ¹ , R ² , R ³ and R ⁴ , at least one of R ⁵ , R ⁶ , R ⁷ and R ⁸ ,
The composition according to claim 1, wherein at least one of R ⁹ , R ¹⁰ , R ¹¹ and R ¹² and at least one of R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are a hydroxyl group. Wherein ^{R 1, R 2, R 3} , R 4, R 5, R 6, R
^{7, R 8, R 9,} R 10, R 11, R 12, R 13, R 14, The composition of claim 2 wherein the remainder of R ¹⁵ and R ¹⁶ are hydrogen or alkyl. 4. The composition according to claim 1, wherein n is 0. 5. The composition according to claim 1 , wherein n is 1 . 6. The alkali-soluble resin is a phenolic compound.
Novolak tree obtained by condensation of aldehydes and aldehydes
Fat and its gel permeation chromatography pattern
Of components with a polystyrene equivalent molecular weight of 900 or less in
The area ratio is the pattern area of the unreacted phenolic compound.
25% or less of the total pattern area except for
The composition according to any one of claims 1 to 5 . 7. An alkali-soluble compound having a molecular weight of 900 or less.
The composition according to any one of claims 1 to 6, further comprising an acidic compound .