KR20080050383A - Chemically amplified polymer having pendant group with dicyclohexyl and resist composition comprising the same - Google Patents

Abstract

A (meth)acrylic carboxylate or norbornene carboxylate compound having a bulky aliphatic ring substituent is provided to obtain a chemically amplified positive resist pattern having high resolution and etching resistance. A 2-alkyl-3-dicyclohexyl-5-norbornene-2-carboxylate compound is represented by the following formula 2. In formula 2, R is methyl or ethyl group; and R* is H or methyl group. The 2-alkyl-3-dicyclohexyl-5-norbornene-2-carboxylate compound represented by formula 2 is obtained by carrying out Diels-Alder reaction between 1-alkyl-1-dicyclohexyl (meth)acrylate represented by the following formula 1 and cyclopentadiene.

Description

TECHNICALLY AMPLIFIED POLYMER HAVING PENDANT GROUP WITH DICYCLOHEXYL AND RESIST COMPOSITION COMPRISING THE SAME}

The present invention provides a novel (meth) acrylic or norbornene carboxylate compound having a dicyclohexyl-bonded pendant group, a method for preparing the same, a chemically amplified polymer synthesized with the compound, and high resolution and corrosion resistance including the polymer. It relates to a photoresist composition for ArF excellent in arousal.

As semiconductor devices become more highly integrated, there is a need for ultra-fine patterns below quarter-microns in dimensions. To this end, the wavelengths of the light sources used for patterning are 193 nm (ArF), 157 nm (VUV), and 248 nm (KrF) at 436 nm (g-line) and 365 nm (I-line). This is shortened by the Rayleigh equation. However, conventionally, there is a limit to using a general resist material at 248 nm in order to obtain a pattern size for devices over 1 giga capacity. Thus, new resists that can perform at shorter wavelengths of 193 nm resists continue to be developed for the demand of finer resolution.

As is well known, the polymers used as the resist material for ArF are classified into three types according to their structure: polyacrylate, cycloolefin-maleic anhydride copolymer, and polynorbornene. Among them, cycloolefin-maleic anhydride copolymer (COMA) type resist is useful in terms of some lithographic performance (pattern collapse, roughness of line edges, SEM beam shrinkage, etching resistance, etc.). Used. However, the COMA-based photoresist undergoes hydrolysis of maleic anhydride (MA) resulting in unsatisfactory results in resolution, in particular dense lines and spatial patterns. In addition, photoresists comprising conventional COMA do not exhibit sufficient resistance and are still difficult to dry etch.

Accordingly, the present invention, in order to solve the above problems of the prior art, (meth) acrylic carboxylate compound or norbornene carboxylate having a substituent of a large aliphatic ring that can increase the high resolution and the corrosion resistance and a method for producing the same The purpose is to provide.

Another object of the present invention is to provide a photosensitive nose suitable for use in chemically amplified resists, including pendant groups having cyclic structures and aliphatic ring compounds that are capable of obtaining sufficient resolution for high integration of semiconductors and are sufficiently resistant to dry etching. It is to provide a polymer and a terpolymer.

It is still another object of the present invention to provide a chemically amplified positive photoresist composition for ArF comprising the photosensitive copolymer, terpolymer and mixtures thereof.

In order to achieve the above object, the present invention

It provides 1-alkyl-1-dicyclohexyl (meth) acrylate represented by the following formula (1):

[Formula 1]

Wherein R is a methyl or ethyl group and R ^* is a hydrogen or methyl group.

In addition, the present invention

a) reacting a dicyclohexyl ketone with an alkyl Grignard reagent or an alkyl lithium reagent to produce 1-alkyl-1-dicyclohexyl alcohol; And

b) of the 1-alkyl-1-dicyclohexyl (meth) acrylate of the formula (1) comprising the step of reacting the (meth) acryloyl chloride and 1-alkyl-1-dicyclohexyl alcohol prepared above It provides a manufacturing method.

In addition, the present invention

2-alkyl-2-dicyclohexyl-5-norbornene-2-carboxylate represented by the following formula (2) is provided:

[Formula 2]

Wherein R is a methyl or ethyl group and R ^* is a hydrogen or methyl group.

In addition, the present invention is a 2-alkyl-2-dicyclohexyl-5 of formula (2) prepared by Diels Alder reaction of 1-alkyl-1-dicyclohexyl (meth) acrylate of the formula (1) and cyclopentadiene Provided is a method for producing norbornene-2-carboxylate.

In addition, the present invention provides a photosensitive copolymer represented by the formula (3):

[Formula 3]

Wherein R is methyl or ethyl, R ^* is hydrogen or methyl and n is an integer from 20 to 25.

The present invention also provides a method for preparing the photosensitive copolymer of Chemical Formula 3 comprising the step of polymerizing the compound of Chemical Formula 2 with maleic anhydride.

In addition, the present invention provides a photosensitive terpolymer represented by the following general formula (4):

[Formula 4]

Wherein R is a methyl or ethyl group; R ^* is hydrogen or a methyl group; R 'is hydrogen, an alkyl group or a hydroxyalkyl group; R "is hydrogen or a methyl group; m and n satisfy m + n = 1, 0.1 <m <0.9, and 0.1 <n <0.9, respectively.

The present invention also provides a method for preparing the photosensitive terpolymer of Chemical Formula 4, comprising the step of polymerizing the compound of Chemical Formula 1 with maleic anhydride and the norbornene compound of Chemical Formula 6.

[Formula 6]

Wherein R 'is hydrogen, an alkyl group or a hydroxyalkyl group, and R "is hydrogen or a methyl group.

In addition, the present invention provides a photosensitive terpolymer represented by the formula (5):

[Formula 5]

Wherein R is a methyl or ethyl group; R ^* is hydrogen or a methyl group; R 'is hydrogen, an alkyl group or a hydroxyalkyl group; R "is hydrogen or a methyl group; m and n satisfy m + n = 1, 0.1 <m <0.9, and 0.1 <n <0.9, respectively.

The present invention also provides a method of preparing the photosensitive terpolymer of Chemical Formula 5 comprising the step of polymerizing the compound of Chemical Formula 2 with maleic anhydride and an acrylate compound of Chemical Formula 7.

[Formula 7]

Wherein R 'is hydrogen, an alkyl group or a hydroxyalkyl group, and R "is hydrogen or a methyl group.

In addition, in the positive photoresist composition for ArF,

For chemically amplified ArF comprising a photosensitive copolymer represented by the formula (3), a photosensitive terpolymer represented by the formula (4), and a polymer selected from the group consisting of the photosensitive terpolymer represented by the formula (5) A positive photoresist composition is provided.

More specifically, in the above formulas R 'is preferably a hydroxy alkyl group having an aliphatic hydrocarbon group or a C ₁ ~C ₁₀ aliphatic hydrocarbon group having a C ₁ ~C _10.

In addition, the present invention provides a semiconductor device prepared by including the positive photoresist composition for ArF.

Hereinafter, the present invention will be described in detail.

The present invention provides a photosensitive copolymer and terpolymer using a (meth) acrylic carboxylate compound or a norbornene carboxylate compound having a substituent of a large aliphatic ring, and using the copolymer and the terpolymer, high resolution and corrosion resistance It is to provide an excellent chemically amplified positive photoresist composition.

The 1-alkyl-1-dicyclohexyl (meth) acrylate of Chemical Formula 1 of the present invention may be prepared by reacting 1-alkyl-1-dicyclohexyl alcohol with (meth) acryloyl chloride.

The method for preparing 1-alkyl-1-dicyclohexyl alcohol follows the following Scheme 1.

Scheme 1

Wherein R is methyl or ethyl and X is Cl or Br.

As shown in Scheme 1, the present invention reacts a dicyclohexyl ketone with an alkyl Grignard reagent or an alkyl lithium reagent to induce an alkyl group at position 1 of the dicyclohexyl ketone to thereby obtain 1-alkyl-1-dicyclohexyl. Alcohol can be prepared. The Grignard reagent includes alkyl magnesium bromide or alkyl magnesium chloride, and methyl magnesium bromide or methyl magnesium chloride is more preferable.

Thereafter, as shown in Scheme 2, the present invention reacts 1-alkyl-1-dicyclohexyl alcohol with (meth) acryloyl chloride to prepare 1-alkyl-1-dicyclohexyl (meth) acrylate. can do.

Scheme 2

Wherein R is methyl or ethyl and R ^* is hydrogen or methyl.

In addition, the present invention can be used to prepare a norbornene compound of formula 2 using the compound of Formula 1.

The present invention is a 2-alkyl-2-dicyclohexyl- of formula (2) having a norbornene substituent by reacting the compounds of formula (1) and cyclopentadiene (Dilels-Alder) as shown in Scheme 3 5-norbornene-2-carboxylate can be prepared.

Scheme 3

Wherein R is methyl or ethyl and R ^* is hydrogen or methyl.

In addition, the present invention can be prepared by using the compound of Formula 1 and Formula 2, the photosensitive copolymer of Formula 3 and the photosensitive terpolymer of Formula 4 and 5.

First, the method for preparing the photosensitive copolymer of Chemical Formula 3 will be described.

Scheme 4

Wherein R, R ^* , and n are as defined above.

As shown in Scheme 4, the photosensitive copolymer of Formula 3 may be obtained by polymerizing a norbornene compound of Formula 2 with maleic anhydride. The polymerization reaction may include an initiator, for example, azobis (isobutyronitrile) (AIBN) may be used. Thus obtained photosensitive copolymer of the formula (3) is preferably a weight average molecular weight of 3,000 to 100,000, the dispersion degree is 1.0 to 5.0.

In addition, the preparation method of the photosensitive terpolymer represented by the formula (4) or (5) of the present invention follows the following scheme (5) or (6), respectively.

Scheme 5

Scheme 6

In the above formulas, R, R ^* , R 'and R "are as defined above.

As shown in Scheme 5, the photosensitive terpolymer of Formula 4 may be obtained by polymerizing the compound of Formula 1 and the norbornene compound of Formula 6 together with maleic anhydride.

In addition, as shown in Scheme 6, the photosensitive terpolymer of Formula 5 of the present invention can be obtained by polymerizing the compound of Formula 2 and the acrylate compound of Formula 7 together with maleic anhydride.

The polymerization of the photosensitive terpolymers of Formulas 4 and 5 may all include an initiator, for example, azobis (isobutyronitrile) (AIBN) may be used. The photosensitive terpolymers of the formulas (4) and (5) thus obtained preferably have a weight average molecular weight of 3,000 to 100,000 and a dispersion degree of 1.0 to 5.0.

In addition, the present invention is a positive photoresist composition for ArF, comprising at least one polymer selected from the group consisting of the photosensitive copolymer of Formula 3, the photosensitive terpolymer of Formula 4, and the photosensitive terpolymer of Formula 5 It provides a chemically amplified positive photoresist composition for ArF.

In the positive photoresist composition of the present invention, the content of at least one polymer selected from the group consisting of the photosensitive copolymer of Formula 3, the photosensitive terpolymer of Formula 4, and the photosensitive terpolymer of Formula 5 may be It is preferably used in an amount of 1 to 30% by weight, more preferably 5 to 8% by weight.

In addition, the photoresist composition of the present invention includes a photoacid generator and a solvent, and may be prepared by mixing various additives as necessary. Preferably, the solid content concentration is 20 to 50% by weight based on 100 parts by weight of the total resist composition. Prepare to be. This is then used by filtration with a 0.2 μm filter.

The content of the photoacid generator is preferably used in an amount of 0.5 to 10% by weight based on the total polymer. The photoacid generator may be selected from the group consisting of onium salts, organic sulfonic acids, and mixtures thereof.

The solvent used in the present invention is ethylene glycol monomethyl ethyl, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether acetate (PGMEA), toluene, xylene, methyl ethyl ketone , Cyclohexanone, 2-hydroxypropion ethyl, 2-hydroxy ethyl 2-methylpropionate, ethyl ethoxy acetate, ethyl hydroxy acetate, 2-hydroxy 3-methylbutyrate, 3-methoxy 2-methyl Methyl propionate, ethyl 3-ethoxy propionate, ethyl 3-methoxy 2-methyl propionate, ethyl acetate, butyl acetate, etc. are mentioned.

In addition, the resist composition of the present invention may further include an organic base, the content of the organic base may comprise 0.01 to 2.00% by weight. The organic base may be selected from one or more selected from the group consisting of triethylamine, triisobutylamine, triisooctylamine, diethanolamine, and triethanolamine.

In addition, the present invention can provide a semiconductor device having an excellent pattern by applying the resist composition to a silicon wafer or an aluminum substrate by using a spin coater to form a resist film and performing exposure, development and baking processes. As the developer, an alkaline aqueous solution in which alkaline compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate and tetramethylammonium hydroxide (TMAH) are dissolved at a concentration of 0.1 to 10% can be used. In addition, an appropriate amount of a water-soluble organic solvent and a surfactant such as methanol and ethanol may be added to the developer. After developing with a developer, the product is washed with ultrapure water.

As described above, the present invention can provide a copolymer and a terpolymer by using a novel (meth) acrylic compound or a norbornene carboxylate compound having a pendant group bonded to a dicyclohexyl, and by using the same, And it can provide a chemically amplified positive photoresist composition for ArF that can exhibit excellent etching resistance to obtain an excellent resist pattern.

Hereinafter, the present invention will be described in detail based on the following examples, but the present invention is not limited to the following examples.

EXAMPLE

Example 1-1: Synthesis of 1-methyl-1-dicyclohexyl (meth) acrylate (R = methyl) (Compound 1)

a) Preparation of 1-methyl-1-dicyclohexyl alcohol

210 ml (0.64 mol) of diethyl ether solution (3.0M) of methyl magnesium bromide were diluted with 200 ml of anhydrous THF. The solution was then placed in a 1 liter flask and the temperature kept at 0 ° C. Dicyclohexyl ketone (62.2 g, 0.32 mol) was slowly added dropwise into the solution through a dropping funnel, followed by reaction at room temperature for about 2 hours. After the reaction was completed, excess THF was removed using a rotary evaporator, neutralized with dilute sulfuric acid, extracted with diethyl ether, and dried over anhydrous magnesium sulfate. The obtained product was purified by column chromatography to obtain 1-methyl-1-dicyclomethyl alcohol (yield 90%) as the target compound.

b) Synthesis of 1-methyl-1-dicyclohexyl acrylate

Dissolve 1-methyl-1-dicyclomethyl alcohol (56.8 g, 0.27 mol) and triethylamine (44.48 mL, 0.32 mol) prepared in a) in 250 ml of THF, and then add acryloyl chloride using a dropping funnel. (26 mL, 0.32 mol) was added slowly. Thereafter, the reaction was carried out at room temperature for 2 hours. After the reaction was completed, excess THF was removed using a rotary evaporator and the product was poured into water. The resulting product was then neutralized with dilute hydrochloric acid, extracted with diethyl ether and dried over anhydrous magnesium sulfate. The obtained product was purified by column chromatography (n-hexane: ethyl acetate = 4: 1) to obtain 1-methyl-1-dicyclohexyl acrylate (yield 70%) as the target compound.

c) Synthesis of 1-methyl-1-dicyclohexyl methacrylate

1-Methyl-1-dicyclohexyl methacrylate was prepared in the same manner as b) except that methacryloyl chloride was used instead of acryloyl chloride.

Example 1-2 Synthesis of 2-methyl-2-dicyclohexyl-5-norbornene-2-carboxylate (R = methyl) (Compound 2)

The 1-methyl-1-dicyclohexyl acrylate (42.3 g, 0.16 mol) prepared in Example 1-1 was dissolved in 250 ml of THF and cyclopentadiene (31.68 g, 0.48 mol) at 0 ° C. Was added slowly and the reaction temperature was raised to room temperature. Thereafter, the reaction was stirred at room temperature for 24 hours. After the reaction was completed, the excess THF was removed using a rotary evaporator, followed by vacuum distillation to give a viscous colorless liquid, which was 2-methyl-2-dicyclohexyl-5-norbornene-2-carboxylate. (Yield 70%) was obtained.

Example 1-3 Synthesis of 1-ethyl-1-dicyclohexyl (meth) acrylate (R = ethyl) (Compound 1)

Except for using 1.0M diethyl ether solution of ethyl magnesium chloride instead of 3.0M diethyl ether solution of methyl magnesium chloride, it was carried out in the same manner as in Example 1-1, each 1-ethyl-1- Dicyclohexyl acrylate and 1-ethyl-1-dicyclohexyl methacrylate were prepared.

Example 1-4: Synthesis of 2-ethyl-2-dicyclohexyl-5-norbornene-2-carboxylate (R = ethyl) (Compound 2)

Except for using 1-ethyl-1-dicyclohexyl acrylate prepared in Example 1-3 instead of 1-methyl-1-dicyclohexyl acrylate prepared in Example 1-1, It was prepared in the same manner as in Example 1-2.

Example 2-1: Synthesis of Copolymer (Compound 3) Using 2-Methyl-2-Dicyclohexyl-5-norbornene-2-carboxylate

33.7 g (0.102 mol) of 2-methyl-2-dicyclohexyl-5-norbornene-2-carboxylate prepared in Example 1-2, maleic anhydride 10.0 g (0.102 mol) and azobis (isobuty) 0.7 g of ronitrile) (AIBN) was dissolved in 25 g of anhydrous THF and degassed using an ampoule as a freezing method. The reaction was then polymerized at 68 ° C. for 24 hours. After completion of the polymerization, the reactant was slowly dropped into excess diethyl ether to precipitate, dissolved in THF again, and reprecipitated in diethyl ether to obtain a copolymer (yield 40%).

The weight average molecular weight and the polydispersity of the obtained copolymer were 8,000 and 1.80, respectively.

Example 2-2: Synthesis of Copolymer (Compound 3) Using 2-Ethyl-2-Dicyclohexyl-5-norbornene-2-carboxylate

The polymerization was carried out in the same manner as in Example 2-1, except that polymerization was carried out using 2-ethyl-2-dicyclohexyl-5-norbornene-2-carboxylate prepared in Example 1-4. Copolymers were prepared.

The weight average molecular weight and the polydispersity of the obtained copolymer were 7,000 and 1.85, respectively.

Example 3-1: Synthesis of Terpolymer (R = Methyl) (Compound 4)

Except for using 1-methyl-1-dicyclohexyl acrylate and 1-methyl-1-dicyclohexyl methacrylate, respectively, 1-methyl-1-dicyclohexyl acrylate or 1 A terpolymer consisting of -methyl-1-dicyclohexyl methacrylate was prepared.

a) Synthesis of terpolymer (R = methyl, R '= hydrogen)

53.9 g (0.204 mol) of 1-methyl-1-dicyclohexyl acrylate prepared in Example 1-1, 14.1 g (0.102 mol) of 5-norbornene-2-carboxylic acid, 10.0 g (0.102 mol) of maleic anhydride And 0.7 g of azobis (isobutyronitrile) (AIBN) were dissolved in 50 g of dry THF, and the gas was removed using an ampoule by the freezing method. The reaction was then polymerized at 68 ° C. for 24 hours. After the polymerization was completed, the reactant was slowly dropped into excess diethyl ether to precipitate, dissolved in THF again, and reprecipitated in diethyl ether to obtain a terpolymer (yield 40%).

The weight average molecular weight and the polydispersity of the obtained terpolymer were 7,000 and 1.8, respectively.

b) terpolymer (R = methyl, R ' = Synthesis of hydroxyethyl)

The polymerization was carried out in the same manner as in a) of Example 3-1, except that polymerization was performed using 2-hydroxyethyl-5-norbornene-2-carboxylate instead of 5-norbornene-2-carboxylic acid. A terpolymer was prepared.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8000 and 1.8, respectively.

c) terpolymer (R = methyl, R ' = Methyl) synthesis

A terpolymer was prepared in the same manner as in Example 3-1, except that polymerization was performed using methyl-5-norbornene-2-carboxylate instead of 5-norbornene-2-carboxylic acid. It was.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8000 and 1.8, respectively.

Example 3-2: Synthesis of Terpolymer (R = ethyl) (Compound 4)

1-ethyl-1-dicyclohexyl acrylate or 1 in the following manner, except that 1-ethyl-1-dicyclohexyl acrylate and 1-ethyl-1-dicyclohexyl methacrylate were used, respectively. A terpolymer consisting of -ethyl-1-dicyclohexyl methacrylate was prepared.

a) Synthesis of terpolymer (R = ethyl, R '= hydrogen)

Example 3-1, except that polymerization was carried out using 1-ethyl-1-dicyclohexyl methacrylate prepared in Example 1-3 instead of 1-methyl-1-dicyclohexyl methacrylate. A terpolymer was prepared in the same manner as in a).

The weight average molecular weight and the polydispersity of the obtained terpolymer were 6,500 and 1.8, respectively.

b) terpolymer (R = ethyl, R ' = Synthesis of hydroxyethyl)

The polymerization was carried out in the same manner as in a) of Example 3-2, except that polymerization was carried out using 2-hydroxyethyl-5-norbornene-2-carboxylate instead of 5-norbornene-2-carboxylic acid. A terpolymer was prepared.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8000 and 1.8, respectively.

c) terpolymer (R = ethyl, R ' = Methyl) synthesis

A terpolymer was prepared by the same method as a) of Example 3-2, except that polymerization was performed using methyl-5-norbornene-2-carboxylate instead of 5-norbornene-2-carboxylic acid. It was.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8500 and 1.8, respectively.

Example 4-1: Synthesis of Terpolymer (Compound 5)

a) terpolymer (R = methyl, R ' = Hydrogen)

33.7 g (0.102 mol) of 2-methyl-2-dicyclohexyl-5-norbornene-2-carboxylate prepared in Example 1-2, 0.44 g (0.005 mol) of methacrylic acid, 10.0 g of maleic anhydride ( 0.102 mol) and 0.7 g of azobis (isobutyronitrile) (AIBN) were dissolved in 25 g of anhydrous THF, and gas was removed using an ampoule as a freezing method. The reaction was then polymerized at 68 ° C. for 24 hours. After the polymerization was completed, the reactant was slowly dropped into excess diethyl ether to precipitate, dissolved in THF again, and reprecipitated in diethyl ether to obtain a terpolymer (yield 40%).

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8,500 and 1.8, respectively.

b) terpolymer (R = methyl, R ' = Synthesis of hydroxyethyl)

A terpolymer was prepared by the same method as a) of Example 4-1, except that polymerization was performed using 2-hydroxyethyl methacrylate instead of methacrylic acid.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8000 and 1.8, respectively.

c) terpolymer (R = methyl, R ' = Methyl) synthesis

A terpolymer was prepared in the same manner as in a) of Example 4-1, except that polymerization was performed using methyl methacrylate instead of methacrylic acid.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8000 and 1.8, respectively.

Example  4-2: Of terpolymer (compound 5)  synthesis

a) terpolymer (R = ethyl, R ' = Hydrogen)

Using 2-ethyl-2-dicyclohexyl-5-norbornene-2-carboxylate prepared in Examples 1-4 instead of 2-methyl-2-dicyclohexyl-5-norbornene-2-carboxylate Except that the polymerization was carried out, a terpolymer was prepared in the same manner as in a) of Example 4-1.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8,500 and 1.8, respectively.

b) terpolymer (R = ethyl, R ' = Synthesis of hydroxyethyl)

A terpolymer was prepared in the same manner as in a) of Example 4-2, except that polymerization was performed using 2-hydroxyethyl methacrylate instead of methacrylic acid.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8500 and 1.8, respectively.

c) terpolymer (R = ethyl, R ' = Methyl) synthesis

A terpolymer was prepared in the same manner as in Example 4-2, except that polymerization was performed using methyl methacrylate instead of methacrylic acid.

The weight average molecular weight and the polydispersity of the obtained terpolymer were 8500 and 1.8, respectively.

Example 5: Preparation of Resist Composition

2.0 g of the copolymer prepared in Example 2-1 and 0.02 g of triphenyl sulfonium triflate (TPS-105) were completely dissolved in 17 g of propylene glycol monomethyl ether acetate (PGMEA). Thereafter, the solution was filtered through a 0.2 μm disc filter to obtain a resist composition. The resist solution was then coated onto a silicon wafer treated with hexamethyldisilazane (HMDS) to a thickness of about 0.30 μm.

The wafer coated with the resist composition was prebaked at 110 ° C. for 90 seconds and exposed using an ArF excimer laser with a numerical aperture of 0.60. Then, post exposure baking (PEB) was performed at 130 ° C. for 90 seconds.

It was then developed for 30 seconds using 2.38 wt% tetramethylammonium hydroxide (TMAH) solution. As a result, when an exposure amount was about 20 mJ / cm <2>, the same line and space pattern of 0.13 micrometer of rectangular shape was obtained. The copolymer of the present invention exhibited excellent etching resistance against conventional COMA by reducing the etching rate for polysilicon by 20%.

Example 6: Preparation of Resist Composition

2.0 g of the terpolymer prepared in Example 3-1 and 0.02 g of triphenyl sulfonium triflate (TPS-105) were completely dissolved in 17 g of propylene glycol monomethyl ether acetate (PGMEA). Thereafter, a resist pattern was formed from a solution in the same manner as in Example 5. The resist pattern exhibited the same line and space pattern of rectangular shape of 0.12 mu m.

Example 7: Preparation of Resist Composition

2.0 g of the terpolymer prepared in Example 4-1 and 0.02 g of triphenyl sulfonium triflate (TPS-105) were completely dissolved in 17 g of propylene glycol monomethyl ether acetate (PGMEA). Thereafter, a resist pattern was formed from a solution in the same manner as in Example 5. The resist pattern exhibited the same line and space pattern of rectangular shape of 0.12 mu m.

The results of the sensitivity, resolution, and pattern shape of the Examples 5 to 7 and the conventionally used COMA type resist are shown in Table 1 below. In addition, Example 7 and the conventional COMA type resist patterns are shown in FIGS. 1 and 2, respectively. In addition, the results of the etching resistance to the oxide (poly) and the etching resistance of the poly (Oxide) of Examples 5 to 7 of the present invention and the conventionally used COMA type resist are shown in FIGS.

Sensitivity (mJ / ㎠) Resolution (μm) Pattern shape Example 5 20 0.13 Rectangular Example 6 22 0.12 Rectangular Example 7 19 0.12 Rectangular Conventional COMA 25 0.14 Tapered

In Table 1 and Figures 1 to 4, it can be seen that the resist according to the present invention has a superior pattern shape than the conventional COMA, and also has excellent etching resistance to (Oxide) and etching resistance to poly (poly). .

1 shows a resist pattern for Embodiment 7 of the present invention.

Figure 2 shows the results of the conventional COMA type resist pattern.

Figure 3 shows the etching resistance results for the oxide (Oxide) of Examples 5 to 7 of the present invention.

Figure 4 shows the etching resistance results for the poly (poly) of the conventional COMA type resist.

Claims (12)

2-alkyl-2-dicyclohexyl-5-norbornene-2-carboxylate represented by the following formula (2): [Formula 2]

Wherein R is a methyl or ethyl group and R ^* is a hydrogen or methyl group. 2-alkyl-2-dicyclohexyl-5-norbornene-2 prepared by Diels Alder reaction of 1-alkyl-1-dicyclohexyl (meth) acrylate and cyclopentadiene of Formula 1 Preparation of carboxylates. [Formula 1]

Wherein R is a methyl or ethyl group, R ^* is hydrogen or a methyl group, [Formula 2]

Wherein R is a methyl or ethyl group and R ^* is a hydrogen or methyl group. Photosensitive copolymer represented by the following formula (3): [Formula 3]

Wherein R is methyl or ethyl, R ^* is hydrogen or methyl and n is an integer from 20 to 25. A method for preparing a photosensitive copolymer of formula (3) comprising the step of polymerizing a compound of formula (2) with maleic anhydride. [Formula 2]

Wherein R is a methyl or ethyl group, R ^* is hydrogen or a methyl group, [Formula 3]

Wherein R is methyl or ethyl, R ^* is hydrogen or methyl and n is an integer from 20 to 25. A photosensitive terpolymer represented by the following formula (5): [Formula 5]

Wherein R is a methyl or ethyl group; R ^* is hydrogen or a methyl group; R 'is hydrogen, an alkyl group or a hydroxyalkyl group; R "is hydrogen or a methyl group; m and n satisfy m + n = 1, 0.1 <m <0.9, and 0.1 <n <0.9, respectively. A method for preparing a photosensitive terpolymer of Formula 5 comprising polymerizing a compound of Formula 2 with maleic anhydride and an acrylate compound of Formula 7 [Formula 2]

Wherein R is a methyl or ethyl group, R ^* is hydrogen or a methyl group, [Formula 5]

Wherein R is a methyl or ethyl group; R ^* is hydrogen or a methyl group; R 'is hydrogen, an alkyl group or a hydroxyalkyl group; R ″ is hydrogen or a methyl group; m and n satisfy m + n = 1, 0.1 <m <0.9, and 0.1 <n <0.9, respectively, [Formula 7]

Wherein R 'is hydrogen, an alkyl group or a hydroxyalkyl group, and R "is hydrogen or a methyl group. In the positive photoresist composition for ArF, A chemically amplified positive photoresist composition for ArF comprising at least one polymer selected from the group consisting of a photosensitive copolymer represented by Formula 3 and a photosensitive terpolymer represented by Formula 5 below: [Formula 3]

[Formula 5]

In which R is a methyl or ethyl group; R ^* is hydrogen or a methyl group; R 'is hydrogen, an alkyl group or a hydroxyalkyl group; R "is hydrogen or a methyl group; m and n satisfy m + n = 1, 0.1 <m <0.9, and 0.1 <n <0.9, respectively. 8. The positive photoresist composition of claim 7, wherein the content of the polymer is 1 to 30% by weight based on the total composition. 8. The positive photoresist composition of claim 7, wherein the photoresist composition further comprises 0.5 to 10% by weight of a photoacid generator based on the total polymer. 10. The positive photoresist composition of claim 9, wherein the photoacid generator is selected from the group consisting of onium salts, organic sulfonic acids, and mixtures thereof. The method of claim 7, wherein the photoresist composition is an organic base selected from the group consisting of triethylamine, triisobutylamine, triisooctylamine, diethanolamine, triethanolamine, and mixtures thereof with respect to the entire polymer 0.01 to A positive photoresist composition, further comprising 2.00% by weight. A semiconductor device manufactured by comprising the positive photoresist composition for ArF according to claim 7.

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