JP2003113174A - Polycyclic compound having lactone structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monomer which gives a polymer suitable as a base resin of a resist material for photolithography using excimer laser as a light source. SOLUTION: A polycyclic compound having a structure expressed by one out of formulae (1) to (4) (wherein, R<1> to R<7> are each independently H or an alkyl; X is a (1-8C alkyl substituted) methylene or ethylene group, or O or S; and n is 0 or a positive integer).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel polycyclic compound having an ethylenically unsaturated bond and a lactone structure. A polymer obtained by polymerizing the compound according to the present invention alone or by copolymerizing it with another compound having an ethylenically unsaturated bond is suitable as a base resin of a resist material for VLSI production.

[0002]

2. Description of the Related Art In recent years, high integration of LSI has been advanced and further miniaturization of pattern rules is required. Far-ultraviolet lithography is expected as a next-generation microfabrication technology that meets this requirement. Among them, photolithography using KrF excimer laser light and ArF excimer laser light as the light source is 0.3 μm.
As a technology indispensable for ultra-fine processing of m or less, its realization is earnestly desired. Excimer laser light, especially wavelength 193
As a base resin of a resist material that exhibits high transparency to ArF excimer laser light of nm, a polyacrylic acid or polymethacrylic acid derivative and an aliphatic cyclic compound such as norbornene-maleic anhydride copolymer are used. A polymer compound contained in the main chain has been studied. Although various properties are required for the base resin, etching resistance and substrate adhesion are also mentioned as important properties. Conventionally, it has been attempted to satisfy these requirements by copolymerizing a plurality of types of monomers having different properties. For example, in JP-A No. 11-212265, a monomer having a polycyclic hydrocarbon group such as adamantyl, tricyclodecyl, norbornyl as a suspending group as a component imparting etching resistance and substrate adhesion are imparted. It is described that a monomer having a polar group such as a hydroxyl group or a carboxyl group as a suspending group is copolymerized as a component for However, it is difficult to uniformly copolymerize an extremely hydrophobic etching resistance imparting monomer with an extremely hydrophilic substrate adhesion imparting monomer, and it is difficult to homopolymerize a homopolymer or an unintended block. By-products such as polymers are produced. When a polymer containing such by-products is used as a base resin for resist materials, non-uniform dissolution due to separation of the inner layer, pattern collapse due to peeling of highly hydrophobic sites, and disordered permeation of developer into highly hydrophilic sites As a result, swelling occurs and the resolution of the resist becomes extremely low.

In order to avoid such problems associated with the copolymerization of a hydrophobic monomer and a hydrophilic monomer,
It has been studied to use a monomer having a hydrophobic site and a polar group in the same molecule as a raw material monomer for the base resin. And a number of monomers that meet such requirements have been proposed. For example, R. Dammel et. a
l. , Journal of Photopolymer
r Science and Technology,
Vol. 12, P433 (1999), a compound represented by the following formula (5) is proposed.

[0004]

[Chemical 2]

Further, in JP-A-10-274852, a compound represented by the following formula (6) is disclosed in JP-A-2000-1.
In Japanese Patent Publication No. 59758, a compound represented by the following formula (7) is proposed.

[0006]

[Chemical 3]

[0007]

All of these compounds give polymers excellent in etching resistance and substrate adhesion, and there is a demand for monomers which give polymers excellent in etching resistance. Accordingly, the present invention seeks to provide such a monomer.

[0008]

The monomers according to the present invention are
It is a polycyclic compound having a lactone structure represented by the following formulas (1) to (4).

[Chemical 4] (In the formula, R ^{1 to} R ⁷ each independently represent a hydrogen atom or an alkyl group. X is a methylene group or ethylene group which may be substituted with an alkyl group having 1 to 8 carbon atoms, an oxygen atom or Indicates a sulfur atom, and n is 0 or a positive integer.)

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION (Polycyclic Compound Having Lactone Structure) In the general formulas (1) to (4), when any of R ^{1 to} R ⁷ represents an alkyl group, the number of carbon atoms is usually 1
To 20, preferably 1 to 8, more preferably 1
To 4, more preferably 1 to 2. The alkyl group may be linear, branched or cyclic. Some examples are methyl group, ethyl group,
n-propyl group, isopropyl group, isobutyl group, 2-
Examples thereof include an ethylhexyl group, a cyclohexyl group, and a methylcyclohexyl group. Here, the general formula (1)
The molecular weight of the compound represented by (4) is usually 6
00 or less, preferably 500 or less, particularly preferably 40
It is 0 or less. Of these, it is particularly preferable that both R ¹ and R ² are hydrogen atoms. R ³ is particularly preferably a hydrogen atom or a methyl group. R ⁴ is particularly preferably a hydrogen atom, a methyl group or an ethyl group. It is particularly preferable that all of R ⁵ to R ⁷ are hydrogen atoms. n is 0 or a positive integer, but if industrial use is assumed, 0,
It is preferably 1, 2, or 3, and more preferably 0 or 1. Further, when n is a positive integer, there are a plurality of R ^{4 s} in the general formulas (1) to (4), and the plurality of R ^{4 s} may be the same or different. Good.

It is generally known that the etching resistance of a resin obtained from a certain monomer depends on the relationship between the numbers of carbon, oxygen and hydrogen atoms constituting the monomer. It is known that the smaller the numerical values calculated by the formulas (8) and (9), the better the etching resistance.

[0011]

[Equation 1]   P1 = (sum of the number of carbon atoms and oxygen atoms constituting the molecule) / the number of carbon atoms ... ( 8)   P2 = (sum of the number of carbon atoms and hydrogen atoms constituting the molecule) / the number of carbon atoms ... ( 9)

The polycyclic compound having a lactone structure of the present invention has a P1 value of 1.1 to 1.4 and a P2 value of 2.1 to 2.4. For example, the compounds represented by the above formulas (5) to (7) and one of the representative compounds of the present invention, where n is 0 and R ¹ and R ^{2 are}
And R ⁴ to R ⁷ are all hydrogen atoms, R ³ is a methyl group, and X is a methylene group, and P 1 and P 2 are as follows.

[Table 1] The compound according to the present invention has a small P1 and P2, and gives a resin having an etching resistance equivalent to or better than the compounds of the formulas (5) to (7). (Production Method of Polycyclic Compound Having Lactone Structure) The compounds represented by the formulas (1) to (4) according to the present invention are represented by the general formula (10) or () according to the following formula (13) or (14). It can be produced by a known method as an addition reaction of carboxylic acids to the double bond of the compound represented by 11).

[0013]

[Chemical 5]

As the acid catalyst, for example, JP-A-3-106 is available.
No. 25, Japanese Patent Laid-Open No. 63-8.
Sulfuric acid disclosed in Japanese Patent No. 355, A. Heidek
umet. al. , Journal of Catal
ysis, Vol. 181, P.I. 217 (1999), ion exchange resins, JM. N. Meba
h et. al. , New Journal of C
chemistry, Vol. 17, P.I. 835 (199
The polyphosphoric acid disclosed in 3) may be used.
Of these, sulfuric acid is preferably used. The reaction is represented by the general formula (1
0) or (11) to the compound represented by the general formula (12) in an amount of 1 to 10 times by mole and an acid catalyst such as sulfuric acid in an amount of 0.05 to 0.5 times by mole. It is preferable to carry out. The reaction can be carried out without a solvent, but if desired, a hydrocarbon solvent such as toluene or an ether solvent such as dioxane can be used. The reaction is preferably carried out at room temperature to 200 ° C, particularly 50 to 150 ° C. After completion of the reaction, the acid catalyst is neutralized and removed, and then the desired product can be isolated and purified by a conventional means such as distillation, crystallization or chromatography. Here, the compound (n = 0) represented by the above formula (11) is a cyclic diene compound represented by the general formula (15) and a methylene represented by the general formula (16) according to the following formula (17). It can be produced by adding a lactone with a Diels-Alder reaction.

[0015]

[Chemical 6]

In this reaction, the compound represented by the formula (15) and the compound represented by the formula (16) are mixed in an equimolar ratio,
By stirring, it is possible to easily proceed even at room temperature or lower. When the cyclic diene compound represented by the general formula (15) is a cyclopentadiene compound, (15) is generated in the reaction system by thermal decomposition of the compound represented by the following formula (15 ′), It is also possible to react as it is with the compound represented by the formula (16). In this case, it is necessary to carry out the reaction at a temperature not lower than the temperature at which (15 ′) can be thermally decomposed into (15), specifically at 150 ° C. or higher.

[Chemical 7] In the Diels-Alder reaction between the compound represented by the formula (15) and the compound represented by the formula (16), if the reaction proceeds violently or the raw material or product is a solid, a hydrocarbon such as toluene. It is preferable to use a system solvent, an oxygen-containing solvent such as ether, or a halogenated hydrocarbon solvent such as methylene chloride. When the reaction progresses slowly, the reaction can be promoted by heating or adding a catalytic amount of a Lewis acid such as boron trifluoride. The reaction product solution obtained is obtained by removing the solvent and unreacted raw materials by distillation or other appropriate means,
Although it can be directly used for the reaction with the above-mentioned carboxylic acid, it can be purified by a conventional means such as distillation, crystallization and chromatography if desired. Also, equation (11)
In the case of a compound in which n is a positive integer, the product obtained above and (15) or (15 ′) may be further reacted a required number of times. The reaction temperature in this case needs to be higher than that in the case of the reaction (17).
Generally, 100 ° C or higher and 300 ° C or lower, preferably 15
It is 0 ° C or higher and 250 ° C or lower. Formula (10) or (11)
As another method for producing the compound represented by the formula (n = 0), the compound represented by the formula (15) and the itaconic anhydride represented by the formula (18) are produced according to the following formula (20). It can also be produced by adding by the Diels-Alder reaction and reducing the produced compound represented by the formula (19).

[0017]

[Chemical 8]

The Diels-Alder reaction in the above formula can take the same conditions as described in the above formula (17). Further, the reaction may be performed by using the above formula (15 ′) instead of the above formula (15). In addition, in the formula (10) or (11), when n is a positive integer, if the intermediate (19) obtained above and (15) or (15 ') are repeatedly reacted n times. Good. The reaction temperature at that time is generally 100 ° C or higher and 300 ° C or lower, preferably 150 ° C or higher and 250 ° C or lower. Formula (20)
Examples of the reducing agent used in the step of reducing the carbonyl group in the reaction represented by M. Kayser a
nd P.n. Morand, Canadian Jour
nal of Chemistry, Vol. 56,
P. The metal hydrides disclosed in 1524 (1978) and the like can be used. For example, lithium aluminum hydride or a substance in which a part of hydrogen atoms thereof are replaced with an alcoholate, or sodium borohydride or a substance in which a part of hydrogen atoms thereof is replaced with an alcoholate can be used. The reaction is preferably carried out in an ether solvent such as ethyl ether or tetrahydrofuran. The reducing agent is preferably used in a stoichiometric amount or an excess amount. The reduction reaction can be generally carried out at -100 ° C to 100 ° C. However, when lithium aluminum hydride or a partial alcoholate thereof is used, it is preferably carried out at -78 to -20 ° C. When a partial alcoholate is used, it is preferably carried out at -20 ° C to 100 ° C. After the completion of the reaction, an acid is added to decompose the reducing agent and its oxidation product, and then the target product can be obtained by extraction and washing with water and used for the reaction with the carboxylic acid. Of course, if desired, purification can be carried out by conventional means such as distillation, crystallization, chromatography and the like. As is clear from the above description, the compounds represented by the general formulas (1) to (4) according to the present invention are usually obtained as a mixture thereof. In addition, each compound has R ^{4 to} R ⁷ for the ring and

[0019]

[Chemical 9]

It is obtained as a mixture of various isomers having different configurations depending on the bonding direction of the group. If desired, they can be separated from each other by crystallization, chromatography, etc., but they are usually used as a mixture for the production of a base resin of a resist material.

[0021]

EXAMPLES The present invention will be described in more detail with reference to the following examples. Example 1 Preparation of bicyclo [2.2.1] heptane-2-ene-6-spiro (2 ', 4'-dioxo-3'-oxa) cyclopentane; 80.00 g (0.714) itaconic anhydride.
mol) in tetrahydrofuran (250 ml) solution,
Cyclopentadiene 56.37 g (0.853 mol) newly obtained by thermally decomposing dicyclopentadiene under water cooling
Was added dropwise over 2 hours. After completion of dropping, the mixture was stirred at room temperature for 6 hours and then left at room temperature overnight. After tetrahydrofuran was distilled off under reduced pressure, the obtained white solid was crushed and suspended in 200 ml of normal hexane, and the suspension was stirred at room temperature for 1 hour and then filtered, and the filter residue was washed with hexane. Hexane was evaporated from the filter cake under reduced pressure to give 8
0.825 g (0.454 mol) of bicyclo [2.
2.1] Heptane-2-ene-spiro (2 ′, 4′-dioxo-3′-oxa) cyclopentane was obtained. The yield based on the raw material itaconic anhydride was 63.5%.

Bicyclo [2.2.1] heptane-2-ene-6-spiro (2'-oxo-3'-oxa) cyclopentane and bicyclo [2.2.1] heptane-2-ene-6- Production of spiro (3'-oxo-4'-oxa) cyclopentane; A 500-ml three-necked flask equipped with a countercurrent condenser, a thermometer and a 100 ml dropping funnel was charged with a stirrer and 80 ml of tetrahydrofuran, and hydrogenated. Sodium boron 4.257 g (112.5 mmo
l) was suspended. The suspension was cooled to 5 ° C. in the flask on an ice bath, and then the bicyclo [2.2.
1] heptane-2-ene-spiro (2 ′, 4′-dioxo-3′-oxa) cyclopentane 20.46 g (11
4.8 mmol), and 3.612 g of methanol (1
Tetrahydrofuran (12.7 mmol) (60 ml)
The solution was added dropwise over 2 hours. During this time, the reaction temperature is 1
The temperature was kept below 0 ° C. After the dropwise addition was completed, the mixture was stirred at 8 ° C. for 20 minutes, and 70 ml of 2N hydrochloric acid was carefully added from the dropping funnel to obtain a colorless and transparent two-layer solution. The aqueous phase (lower layer) was separated, concentrated under reduced pressure to about 50 ml, and extracted once with 50 ml of toluene. On the other hand, the solvent of the tetrahydrofuran phase (upper layer) was distilled off under reduced pressure. To the residue, 150 ml of toluene and 50 ml of a toluene extract obtained by previously extracting the aqueous phase were added, and the mixture was stirred for 30 minutes, then the insoluble white solid was filtered off to give a colorless transparent toluene solution. 4 with each 50 ml of saturated sodium bicarbonate
It was washed twice and then 4 times with 50 ml of pure water each time. After drying over anhydrous magnesium sulfate, the solvent was distilled off,
When the residue was distilled under reduced pressure (130 ° C./5 mmHg), 12.714 g (77.43 mmol) of a colorless transparent liquid was obtained. As a result of 1 H-NMR analysis, this product was found to be bicyclo [2.2.1] heptane-2-ene-spiro (2′-oxo-3′-oxa) cyclopentane and bicyclo [2.2.1] heptane-2. It was found to be a mixture of -ene-6-spiro (3'-oxo-4'-oxa) cyclopentane, the yield was 67.4%.

Bicyclo [2.2.1] heptane-6-spiro (2'-oxo-3'-oxa) cyclopentane-
2-ylmethacrylate, bicyclo [2.2.1] heptane-6-spiro (2'-oxo-3'-oxa) cyclopentan-3-ylmethacrylate, bicyclo [2.
2.1] Heptane-6-spiro (3'-oxo-4'-
Oxa) cyclopentan-2-ylmethacrylate and bicyclo [2.2.1] heptane-6-spiro (3 '
Preparation of -oxo-4'-oxa) cyclopentan-3-ylmethacrylate mixture; bicyclo [2.2.1] heptane-2-ene-spiro (2'- in 100 ml eggplant-shaped flask. Oxo-3′-oxa) cyclopentane and bicyclo [2.2.1] heptane-2-
12.15 g (74.0 mmo) of a mixture of ene-6-spiro (3'-oxo-4'-oxa) cyclopentane.
l), 25.50 g of methacrylic acid (296.2 mmo)
1) and 4-methoxyphenol 14.6 mg were mixed to make a uniform solution. 95% concentrated sulfuric acid (1.943 g)
(18.8 mmol) and add 1 while stirring on an oil bath.
Hold at 20 ° C. for 2 hours. After cooling the reaction solution to room temperature,
An aqueous solution (20 ml) of 2.02 g (19.06 mmol) of sodium carbonate was added to neutralize sulfuric acid. Toluene 2
0 ml was added, and the mixture was stirred and then allowed to stand to separate the layers.
The aqueous phase was separated, the oil phase was treated at 70 ° C./10 mmHg for 1 hour, and toluene and methacrylic acid were distilled off. 20m each
It was washed 4 times with 1 l of a saturated sodium hydrogen carbonate aqueous solution, and further washed 4 times with 10 m of pure water. After drying over anhydrous magnesium sulfate, 30 ml of toluene and silica gel for chromatography were added to give a suspension. This is stirred at room temperature for 1 hour, the silica gel is filtered off, washed with toluene,
The filtrate and the washing solution were combined. When the solvent was distilled off from this, 15.60 g of an oily yellow transparent product was obtained. Most of the product crystallized when left at room temperature. When developed by capillary gas chromatography, it was found to consist of at least 8 compounds with similar retention times. The yield was 84.2%. The analysis results are shown below.

(1) Actual value of elemental analysis: C, 67.31%; H, 7.23%. Calculated: C, 67.18%; H, 7.25%. (2) Infrared spectrum 1770 cm-1 (lactone CO); 1710 cm-1 (methacrylate CO). (3) For the ¹ H-NMR (CDCl ₃ , δppm) assignment, see the formula (21). 6.09-6.08 (1H, a); 5.56-5.55.
(1H, b); 4.87-4.67 (1H, c);
30-4.00 (2H, d); 2.61-2.36 (2
H, e); 2.20-2.19 (1H, f); 2.14
-1.96 (1H, g); 1.93 (3H, h);
82-1.66 (2H, i); 1.57-1.47 (2
H, j, k); 1.43-1.23 (2H, 1). (4) For the assignment of ¹³ C-NMR (CDCl ₃ , δppm), see formula (22). 176.6, 176.5 (a); 167.2, 167.
1 (b); 136.6, 136.3 (c); 126.0
-125.2 (d); 80.3 (e); 76.1, 7
6.0 (f); 46.2-33.9 (g-m); 18.
5,18.4 (n).

[0025]

[Chemical 10]

[0026]

[Chemical 11] Example 2 Tetracyclo [6.2.1.1^3,6． 0^2,7] Dodeca-9
-Ene-4-spiro (2 'or 4'-oxo-3'-
Oxa) cyclopentane production; bicyclo [2.2.
1] Hept-5-ene-2-spiro (2 ', 4'-dio
57.5 g (35) of xoxo-3'-oxa) cyclopentane
0 mmol), 23.1 g of dicyclopentadiene (17
5 mmol) and 30 ml of toluene 200 m of induction stirring type
1 The autoclave was charged and the system was replaced with nitrogen gas.
Then, the temperature was raised to 220 ° C. and the reaction was carried out at this temperature for 3 hours. cold
After discarding, the reaction solution is taken out and distilled, and 165 to 172
19.60 g of a fraction at ℃ (0.3 mmHg) was obtained. this
And 19.6 g (81.0 mmol) of methanol
Lahydrofuran (50 ml) solution, sodium borohydride
3.06 g (81.0 mmol) of tetrahydro
Furan (100 ml) suspension was placed on an ice bath and the flask temperature was 5
It was added dropwise while being cooled to ℃. 1 hour at room temperature after dropping
After stirring, 80 ml of 1N hydrochloric acid was added. This solution
Was concentrated under reduced pressure and extracted with 100 ml of toluene.
It was Wash 3 times with 20 ml each of 5 wt% sodium hydrogen carbonate
It was then washed 3 times with 20 ml of pure water each time. Anhydrous sulfur
After drying with magnesium acidate, the solvent is distilled off, and distillation is performed to obtain 15
7.42 g of a fraction of 4 to 155 ° C. (0.5 mmHg) was obtained.
Was given. As a result of mass spectrometry, [M⁺] Is 244,
Tracyclo [6.2.1.1^3,6． 0^2,7] Dodeca-9-
En-4-spiro (2 'or 4'-oxo-3'-o
It was found to be cyclopentane. Tetracyclo [6.2.1.1^3,6． 0^2,7] Dodecane-
4-spiro (2 'or 4'-oxo-3'-oxa)
Preparation of cyclopentan-9-yl acrylate: Ac
7.70 g (107 mmol) of phosphoric acid, 95% by weight sulfuric acid
0.540 g, toluene 7 ml and 4-methoxypheno
3 mg of the alcohol in a three-necked 100 ml flask,
Heated to ° C. In this, tetracyclo [6.2.1.1
^3,6． 0^2,7] Dodeca-9-en-4-spiro (2 'again
Is 4'-oxo-3'-oxa) cyclopentane 3.1
A solution of 0 g (13.5 mmol) in 3 ml of toluene was added dropwise.
After that, it was heated at 90 ° C. for 3 hours. After cooling the reaction mixture with water
After adding to 10 ml, it was extracted with 20 ml of toluene. To
Ruene layer was mixed with 10 ml of 5% by weight aqueous sodium chloride solution.
It was washed twice, and then washed 3 times with 5 ml of pure water each time. anhydrous
When the solvent was distilled off after drying over magnesium sulfate,
3.70 g of a yellow viscous liquid was obtained. Mass spectrometry results
From the fruit [M⁺] Is 302, and tetracyclo [6.
2.1.1^3,6． 0 ^2,7] Dodecane-4-Spiro (2 ’
Or 4'-oxo-3'-oxa) cyclopentane-9
-It was confirmed to be yl acrylate.

[0027]

EFFECTS OF THE INVENTION A resist material containing a polymer obtained by polymerizing the compound according to the present invention as a base resin is sensitive to high energy rays and is excellent in sensitivity, resolution and etching resistance. It is also useful for fine processing with deep UV. In particular, since the absorption at the exposure wavelength of the ArF excimer laser and the KrF excimer laser is small, it is possible to easily form a fine pattern perpendicular to the substrate.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Taketoshi Naito             1000 Kamoshida-cho, Aoba-ku, Yokohama-shi, Kanagawa             Within Mitsubishi Chemical Corporation F term (reference) 2H025 AA09 AA14 AB16 AC04 AC06                       AC08 AD01 AD03 CB14 CB41                 4C037 WA01                 4J100 AL08P BA11P BC07P BC08P                       BC53P BC83P JA38

Claims (7)

[Claims] 1. A polycyclic compound having a lactone structure represented by the following formulas (1) to (4). [Chemical 1] (In the formula, R ^{1 to} R ⁷ each independently represent a hydrogen atom or an alkyl group. X is a methylene group or ethylene group which may be substituted with an alkyl group having 1 to 8 carbon atoms, an oxygen atom or Indicates a sulfur atom, and n is 0 or a positive integer.) 2. The polycyclic compound having a lactone structure according to claim 1, wherein n is 0, 1, 2 or 3. 3. The lactone structure according to claim 1 or 2, wherein when any of R ¹ to R ⁷ is an alkyl group, the alkyl group has 1 to 8 carbon atoms. Polycyclic compound. 4. The polycyclic compound having a lactone structure according to claim 1, wherein X is a methylene group. 5. The polycyclic compound having a lactone structure according to claim 1, wherein R ¹ and R ² are hydrogen atoms and R ³ is a hydrogen atom or a methyl group. . 6. R ¹ , R ² and R ⁴ to R ⁷ are all hydrogen atoms, R ³ is a hydrogen atom or a methyl group, and X
Is a methylene group.
A polycyclic compound having a lactone structure according to any one of 1. 7. R ¹ , R ² and R ⁵ to R ⁷ are all hydrogen atoms, R ³ is a hydrogen atom or a methyl group, and R ⁴
Is a methyl group or an ethyl group, and X is a methylene group, The polycyclic compound having a lactone structure according to any one of claims 1 to 5.