KR20060051330A - Photoresist monomer having spiro cyclic ketal group, polymer thereof and photoresist composition including the same - Google Patents

Abstract

Disclosed are a polymer for photoresist having a spiro cyclic ketal group and a photoresist composition comprising the same, polymerized using a monomer represented by the following formula. The polymer and photoresist composition may have a low activation energy of a reaction in which a spiro cyclic ketal group is deprotected, thereby improving resolution and process margin, and having a low post-exposure bake temperature sensitivity (PEB sensitivity), thereby achieving a precise pattern. It can improve the depth of focus margin and line edge roughness.

In the above formula, R ^* is hydrogen or a methyl group, x and y are each independently 1, 2 or 3, R is a mono-cyclic or multi-cyclic of 3 to 50 carbon atoms Homo or hetero saturated hydrocarbon groups.

Photoresist, Line Edge Roughness

Description

Photoresist monomer having spiro cyclic ketal group, polymers and photoresist composition including the same}

1 to 8 are electron scanning micrographs of photoresist patterns formed using photoresist compositions according to embodiments of the present invention, respectively.

The present invention relates to a monomer for a photoresist having a spiro cyclic ketal group, a polymer, and a photoresist composition comprising the same. More specifically, the activation energy of the reaction in which the spiro cyclic ketal group is deprotected is low, so that the resolution and process margin The present invention relates to a monomer for a photoresist having a spiro cyclic ketal group, a polymer, and a photoresist composition comprising the same.

Recently, with high integration and high precision of semiconductor devices, it is required to form ultra-fine photoresist patterns having a half pitch of less than 90 nm in a photo lithography process. Accordingly, while the wavelength of the mass production exposure source is shortened to less than 193 nm, the development of technology for further optimizing and precision of the wafer processing process is in progress. In order to realize such a precise pattern, a photosensitive material having low line edge roughness, low post exposure baking sensitivity and low dry etching resistance is required.

In the process of forming a photoresist pattern, in order to improve the resolution and process margin and to form a more precise pattern, a protecting group which is attached to the side chain of the photoresist polymer and serves to suppress dissolution in basic solution It is preferable to lower the activation energy of the reaction in which) is deprotected or to use a material having a low post-exposure bake temperature sensitivity. For example, polyacrylates, cycloolefin-maleic anhydride copolymers, and polynorbornene, which are polymers for photoresists used in ArF exposure sources, have activation energies of reactions in which a protecting group attached to the side chain of the polymer is deprotected. Ii) a polymer having a high activation energy protecting group such as tertiary butyl group, ii) a polymer having a neutral activation energy protecting group such as methyl adamantyl group or ethyl adamantyl group, iii) a polymer such as acetal group or ketal group It can be classified as a polymer having a low activation energy protecting group. As a photoresist polymer used in an exposure source of ArF, poly (meth) acrylate having an acetal group as a low activation energy protecting group is disclosed in U.S. Patent No. 4,975,519, U.S. Patent Application Publication No. 2002-0143130 (2002.10.03) and International Patent WO 2002-20214 (2002.3.14) and the like.

Accordingly, an object of the present invention is to lower the activation energy of the reaction in which the protecting group is deprotected in order to prepare a photosensitive resist that meets the conditions required by the exposure technique, thereby improving the resolution and process margin, and post-exposure bake temperature. It is to provide a photoresist monomer, a polymer having a spiro cyclic ketal group, and a photoresist composition comprising the same, because of low sensitivity.

Another object of the present invention is to provide a photoresist monomer having a spiro cyclic ketal group, a polymer, and a photoresist composition comprising the same, which can improve the depth of focus margin and the line edge roughness.

Still another object of the present invention is to provide a method for preparing the monomer and polymer and a method for forming a photoresist pattern using the photoresist composition.

In order to achieve the above object, the present invention provides a monomer having a spiro cyclic ketal group represented by the following formula (1).

[Formula 1]

In Formula 1, R ^* is hydrogen or a methyl group, x and y are each independently 1, 2 or 3, R is a mono-cyclic or multi-cyclic having 3 to 50 carbon atoms Is a homo or hetero saturated hydrocarbon group.

The present invention also provides a photoresist polymer having a spiro cyclic ketal group, which includes a repeating unit represented by the following formula (2).

 [Formula 2]

In Formula 2, R ^* , R, x and y are as defined in Formula 1.

The present invention also provides a photoresist composition comprising the polymer and a method of forming a photoresist pattern using the photoresist composition.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

The monomer for photoresists having a spiro cyclic ketal group according to the present invention is represented by the following formula (1).

,

,

,

,

,

,

,

,

,

,

, 또는

이다(여기서, 나선(

)은 연결부(connecting bond)를 나타낸다.). In Formula 1, R ^* is hydrogen or a methyl group, x and y are 1, 2 or 3, R is a mono-cyclic or multi-cyclic homo or hetero having 3 to 50 carbon atoms Saturated hydrocarbon group, preferably

,

,

,

,

,

,

,

,

,

,

, or

(Where the spiral (

Denotes a connecting bond.

The monomer having a spiro cyclic ketal group represented by Formula 1 according to the present invention can be prepared by a conventional organic synthesis method. For example, first, as shown in Scheme 1 below, cyclic ketal alcohol is prepared by reacting cyclic ketone with trialcohol under an acid catalyst.

In Scheme 1, R, x and y are as defined in Formula 1.

The acid catalyst may be used a wide range of acid catalysts commonly used, for example, may be used paratoluene sulfonic acid. The reaction can be carried out in a conventional organic solvent such as normal heptane for 1 to 24 hours at a temperature of 30 to 100 ℃ and atmospheric pressure in a nitrogen or argon atmosphere.

Next, as the spiro cyclic ketal alcohol thus prepared is reacted with (meth) acryloyl chloride under a base catalyst, as shown in Scheme 2, a monomer represented by Chemical Formula 1 may be prepared.

In Scheme 2, R ^* , R, x and y are as defined in Formula 1.

As the base catalyst, a commonly used base catalyst can be widely used, for example, triethylamine can be used. The reaction can be carried out in a conventional organic solvent such as tetrahydrofuran (THF) for 1 to 24 hours under an inert atmosphere such as nitrogen, argon, at a temperature of 0 to 60 ℃ and atmospheric pressure.

The photoresist polymer having a spiro cyclic ketal group according to the present invention includes a repeating unit represented by the following formula (2).

In Formula 2, R ^* , R, x and y are as defined in Formula 1. In the photoresist polymer having a spiro cyclic ketal group according to the present invention, the repeating unit of the formula (2) is 1 to 99 mol% and 1 to 99 mol%, preferably on the basis of the mol% of the repeating unit in the upper and lower polymer chains, respectively. Preferably it may be included in the content of 5 to 95 mol%, 5 to 95 mol%, as the monomer used with the repeating unit of Formula 2 may be used a variety of monomers commonly used in the photoresist polymer.

In addition, preferred examples of the photoresist polymer having a spiro cyclic ketal group according to the present invention are polymers represented by the following general formula (3), and more preferred examples are polymers represented by the following general formulas (3a to 3h).

In Formulas 3 and 3a to 3h, R ^* and R ^** are each independently hydrogen or a methyl group, R ₁ is each independently a linear or cyclic alkyl group having 1 to 20 carbon atoms, and a and b are upper and lower polymer chains. As mole% of the repeating unit which constitutes 1 to 99 mol% and 1 to 99 mol%, preferably 1 to 95 mol%, 1 to 95 mol%, more preferably 5 to 95 mol%, 5 to 95 Mole%, and x, y and R are as defined in Formula 1 above. The polymer may be a block copolymer or a random copolymer.

A spiro cyclic ketal group, which is a bulky saturated hydrocarbon, attached to the side chain of the photoresist polymer according to the present invention, is a protecting group for preventing the polymer and the photoresist composition including the same from being dissolved in a basic solution such as a basic developing solution ( As a protecting group, while deprotected by an acid catalyst (H ⁺ ) generated in the photoacid generator of the exposed part, the solubility of the exposed part is increased to increase the contrast of the photoresist composition. In particular, the spiro cyclic ketal group is deprotected. Since the activation energy of the reaction is low, process margins such as the resolution of the resist pattern and the energy process margin can be improved, and since the product of the deprotection reaction is a bulky substance of high molecular weight, the depth of focus margin and the line edge rough Nice can be improved.

According to the present invention, a polymer for a photoresist composition comprising a repeating unit represented by Chemical Formula 2 includes a) dissolving at least one monomer and a polymerization initiator containing the monomer represented by Chemical Formula 1 in a polymerization solvent, b) The mixture solution may be prepared by reacting for 4 to 24 hours at a temperature of 60 to 70 ℃ under an inert atmosphere such as nitrogen, argon and the like. In addition, the polymerization may be performed by a radical polymerization reaction, a solution polymerization reaction, a bulk polymerization reaction or a polymerization reaction using a metal catalyst. In addition, the preparation method further includes the step of crystallizing the reaction product (b) using diethyl ether, petroleum ether, lower alcohols including methanol, ethanol or isopropanol, water, mixtures thereof, and the like. You may.

A monomer which can be polymerized with the monomer represented by Formula 1 may be used a monomer which is commonly used in the manufacture of a photoresist polymer, without limitation, it is a monomer having a sensitive protecting group on ⅰ) acid, t - Butyl, tetrahydropyran-2-yl, 2-methyl tetrahydropyran-2-yl, tetrahydrofuran-2-yl, 2-methyl tetrahydrofuran-2-yl, 1-methoxypropyl, 1-methoxy -1-methylethyl, 1-ethoxypropyl, 1-ethoxy-1-methylethyl, 1-methoxyethyl, 1-ethoxyethyl, t -butoxyethyl, 1-isobutoxyethyl or 2-acetylment The monomer which has a protecting group, such as -1-yl, can be illustrated, for example, ii) The monomer represented by following formula (4) can be illustrated, Specifically, 2-methyl- 2-adamantyl (meth) acrylate Can be used.

In Formula 4, R ^** and R ₁ are as defined in Formula 3.

The monomer represented by Chemical Formula 1 and the monomer represented by Chemical Formula 4 may be polymerized as in Scheme 3 below to prepare a photoresist polymer represented by Chemical Formula 3.

R ^* in Scheme ^{3, R **, R, R} 1, x, y, a and b are as defined in the formula (3).

As the polymerization solvent of the polymerization reaction, a polymerization solvent commonly known in the art may be widely used, but is not limited to cyclohexanone, cyclopentanone, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, dioxane, Methyl ethyl ketone, benzene, toluene, xylene, or mixtures thereof may be exemplified, and the polymerization initiator may also be widely used as polymerization initiators commonly known in the art, but is not limited to benzoyl peroxide, 2, 2'-azobisisobutyronitrile (AIBN), acetylperoxide, lauryl peroxide, t-butylperacetate, t-butylhydroperoxide, di-t-butylperoxide or mixtures thereof have. The photosensitive polymers of Chemical Formulas 2 to 3 preferably have a weight average molecular weight (Mw) of 3,000 to 100,000 and a polydispersity of 1.0 to 5.0. When the weight average molecular weight and the dispersion degree are outside the above ranges, the physical properties of the photoresist film may be lowered, or the formation of the photoresist film may be difficult, and the contrast of the pattern may be lowered.

 The photoresist composition according to the present invention includes a photosensitive polymer including a repeating unit represented by Chemical Formula 2, a photoacid generator for generating an acid, and an organic solvent, and may further include various additives as necessary. The content of the photosensitive polymer including the repeating unit represented by Formula 2 is preferably 1 to 30% by weight based on the total photoresist composition, and more preferably 5 to 15% by weight. If the content of the photosensitive polymer is less than 1% by weight, the resist layer remaining after coating is too thin to form a pattern having a desired thickness, and if it exceeds 30% by weight, coating uniformity may be deteriorated.

The photoacid generator generates an acid component such as H ⁺ by exposure and serves to deprotect the protecting group of the photosensitive polymer, and any compound capable of generating an acid by light may be used. Can be used sulfide salt compounds such as eutectic acid, onium salt compounds such as onium salts, and mixtures thereof. Non-limiting examples of photoacid generators include phthalimidotrifluoromethane sulfonate, dinitrobenzyltosylate, n-decyl disulfone, and naph with low absorbance at 157 nm and 193 nm. Naphthylimido trifluoromethane sulfonate, diphenylurodoxyl hexafluorophosphate, diphenylurodoxyl hexafluoro arsenate, diphenylurodoxyl hexafluoro antimonate, diphenylparamethoxyphenylsulfonate Phosphonium triflate, diphenylparatoluenylsulfonium triflate, diphenylparaisobutylphenylsulfonium triflate, triphenylsulfonium hexafluoro arsenate, triphenylsulfonium hexafluoro antimonate, triphenylsulfon Phonium triflate, dibutylnaphthylsulfonium triflate, and mixtures thereof. The content of the photoacid generator is preferably 0.05 to 10% by weight based on the polymer for photoresist (that is, 0.05 to 10 parts by weight based on 100 parts by weight of the polymer). If it is less than 0.05% by weight, the sensitivity of the photoresist composition to light decreases, which may make it difficult to deprotect the protective group. If it exceeds 10% by weight, a large amount of acid may be generated in the photoacid generator, resulting in poor cross-section of the resist pattern. There is concern.

As the organic solvent constituting the remaining components of the photoresist composition according to the present invention can be used a wide variety of organic solvents commonly used in the preparation of the photoresist composition, non-limiting examples include ethylene glycol monomethyl ether, ethylene glycol Monoethyl ether, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol, propylene glycol monoacetate, toluene, xylene, methyl ethyl ketone, methyl isoamyl ketone, Cyclohexanone, dioxane, methyl lactate, ethyl lactate, methylpyruvate, ethylpyruvate, methylmethoxypropionate, ethylethoxy propionate, N, N-dimethylformamide, N, N-dimethyl Acetamide, N-methyl 2-pyrrolidone, 3-ethoxyethylpropionate, 2-heptanone, persimmon Butyrolactone, 2-Hydroxypropionate, 2-hydroxyethyl 2-methylpropionate, ethyl ethoxy acetate, ethyl hydroxyacetate, 2-hydroxy 3-methylbutyrate, 3-methoxy 2-methyl Methyl propionate, ethyl 3-ethoxypropionate, ethyl 3-methoxy 2-methylpropionate, ethyl acetate, butyl acetate, and mixtures thereof can be exemplified.

In addition, the photoresist composition according to the present invention may further include an organic base as needed, non-limiting examples of the organic base is triethylamine, triisobutylamine, triisooctylamine, diethanolamine, triethanol Amines and mixtures thereof can be exemplified. The content of the organic base is preferably 0.01 to 2.00 wt% based on the total photoresist composition. If the content of the organic base is less than 0.01% by weight, a t-top phenomenon may occur in the resist pattern, and if the content is more than 2.00% by weight, the sensitivity of the photoresist composition may be reduced and the pattern formation rate may be lowered. have.

The photoresist composition according to the present invention may be prepared by blending the photosensitive polymer, photoacid generator, organic solvent, and various additives as necessary, and filtering by a filter, if necessary, wherein the solid content concentration with respect to the entire photoresist composition It is preferable to make it from 10 to 60 weight%. When the concentration of the solid content is less than 10% by weight, the resist layer is too thin to form a pattern having a desired thickness, and when it exceeds 60% by weight, the coating layer uniformity may be deteriorated.

In order to form a photoresist pattern using the photoresist composition according to the present invention, first, the photoresist composition is applied to a substrate such as a silicon wafer or an aluminum substrate using a spin coater to form a photoresist film. After the photoresist film is exposed to a predetermined pattern, a conventional photolithography process of exposing and exposing the exposed photoresist pattern (PEB) and developing may be used. A semiconductor device having a circuit pattern can be manufactured. As a developer used in the developing step, an alkaline aqueous solution of 0.1 to 10% by weight of an alkaline compound such as sodium hydroxide, potassium hydroxide, sodium carbonate, tetramethylammonium hydroxide (TMAH), and the like can be used. An appropriate amount of a water-soluble organic solvent such as methanol or ethanol and a surfactant may be added to the mixture. In addition, after the development process, the cleaning process may be further performed to clean the substrate with ultrapure water.

Hereinafter, the present invention will be described in more detail with reference to specific examples. The following examples are intended to illustrate the present invention more specifically, but the scope of the present invention is not limited by the following examples.

Example 1-1 Preparation of Monomers Represented by Formula 5a

In a 500 mL three necks round bottom flask, 24.0 g (0.26 mol) of glycerol, 9.8 g (0.1 mol) of cyclopentane-1,3-dione and paratoluenesulphonic acid 0.15 g was added thereto and 60 g of normal heptane was added thereto. Then, a Dean-Stark trap was installed in the flask, and the reaction was performed under reflux at 98 ° C. for 12 hours. After the reaction was completed, the reaction was cooled to room temperature, the cooled reaction was placed in a separatory funnel, the layered unreacted polyol was removed, and the spiro cyclic ketal alcohol obtained by removing the polyol was purified using column chromatography. It was. Purified spiro cyclic ketal alcohol was placed in a three necked round bottom flask and diluted by addition of 30 g of tetrahydrofuran (THF). To the diluted reaction, 20.8 g of methacryloyl chloride (or 18.2 g of acryloyl chloride) and 50 g of tetrahydrofuran were added using a dropping funnel. Then, 10 mL of triethylamine was added thereto, followed by 12 hours in a nitrogen atmosphere. The reaction was carried out while refluxing. After the reaction was completed, the reaction was depressurized to remove the solvent, the reaction was separated by liquid chromatography (silica gel, hexane: ether = 6: 1) to remove the solvent again. The reaction product from which the solvent was removed was recrystallized with hexane, and then allowed to stand at room temperature to obtain a monomer represented by the following Chemical Formula 5a in a yield of 55% {H-NMR: i) R ^* = H, d (6.52, 2H), m (6.16, 2H), d (5.98, 2H), m (4.56, 2H), m (4.31, 4H), m (3.91, 4H), m (3.63, 2H), m (1.96, 6H) ii) R ^* = CH ₃ , s (6.56, 2H), d (5.86, 2H), m (4.96, 2H), m (4.63, 4H), m (4.42, 4H), m (3.69, 2H), m (1.35 , 12H)}.

In Formula 5a, R ^* is hydrogen or a methyl group.

Example 1-2 Preparation of Monomer Represented by Formula 5b

50% of the monomer represented by the following Chemical Formula 5b was obtained in the same manner as in Example 1-1 except that 11.2 g of cyclohexane-1,4-dione was used instead of 9.8 g of cyclopentane-1,3-dione. Yield {H-NMR: i) R ^* = H, d (6.46, 2H), m (6.16, 2H), d (5.88, 2H), m (4.36, 2H), m (4.21, 4H), m (4.11, 2H), m (3.79, 2H), m (1.85, 8H) ii) R ^* = CH ₃ , s (6.16, 2H), d (5.88, 2H), m (4.36, 2H), m (4.21, 4H), m (4.11, 2H), m (3.79, 2H), m (1.85, 14H)}.

In Formula 5b, R ^* is hydrogen or a methyl group.

Example 1-3 Preparation of Monomer Represented by Formula 5c

Same as Example 1-1 except that 16.6 g of 1,5-dimethylbicyclo [3,3,0] octane-3,7-dione was used instead of 9.8 g of cyclopentane-1,3-dione. By the method, the monomer represented by the following Chemical Formula 5c was obtained in a yield of 55%. {H-NMR: i) R ^* = H, d (6.46, 2H), m (6.13, 2H), d (5.38, 2H), m (4.89, 2H), m (4.71, 4H), m (4.31, 2H), m (3.52, 2H), m (1.85, 16H) ii) R ^* = CH ₃ , s (6.36, 2H), d ( 5.68, 2H), m (4.86, 2H), m (4.36, 4H), m (4.14, 2H), m (3.69, 2H), m (1.25, 22H)}.

In Formula 5c, R ^* is hydrogen or a methyl group.

Example 1-4 Preparation of Monomers Represented by Formula 5d

Except for using 9.8g of cyclopentane-1,3-dione, 75.2-dimethylnorbornane-2,3-dione was used in the same manner as in Example 1-1 except that 15.2g The monomer was obtained in a yield of 65% {H-NMR: i) R ^* = H, d (6.05, 2H), m (6.25, 2H), d (5.18, 2H), m (4.86, 2H), m ( 4.61, 4H), m (4.31, 2H), m (3.29, 2H), m (1.25, 12H) ii) R ^* = CH ₃ , s (6.16, 2H), d (5.86, 2H), m (4.86 , 2H), m (4.51, 4H), m (4.21, 2H), m (3.29, 2H), m (1.75, 18H)}.

In Formula 5d, R ^* is hydrogen or a methyl group.

Example 1-5 Monomer Preparation represented by Chemical Formula 5e

55% of the monomer represented by the following Chemical Formula 5e by the same method as Example 1-1 except for using 16.4 g of adamantane-2,6-dione instead of 9.8 g of cyclopentane-1,3-dione Yield of {H-NMR: i) R ^* = H, d (6.86, 2H), m (6.15, 2H), d (5.52, 2H), m (4.95, 2H), m (4.61, 4H) , m (4.55, 2H), m (3.52, 2H), m (1.25, 12H) ii) R ^* = CH ₃ , s (6.56, 2H), d (5.68, 2H), m (4.66, 2H), m (4.45, 4H), m (4.15, 2H), m (3.45, 2H), m (1.85, 18H)}.

In Formula 5e, R ^* is hydrogen or a methyl group.

Example 1-6 Preparation of Monomer Represented by Formula 5f

Monomer represented by the following formula (5f) in the same manner as in Example 1-1, except that 23.6 g of 2,2-bis-4'-oxo cyclohexyl propane was used instead of 9.8 g of cyclopentane-1,3-dione Was obtained in a yield of 50% {H-NMR: i) R ^* = H, d (6.20, 2H), m (6.01, 2H), d (5.80, 2H), m (4.96, 2H), m (4.38) , 4H), m (4.21, 2H), m (3.29, 2H), m (1.35, 24H) ii) R ^* = CH ₃ , s (6.36, 2H), d (5.88, 2H), m (4.66, 2H), m (4.21, 4H), m (4.01, 2H), m (3.79, 4H), m (1.55, 30H)}.

In Formula 5f, R ^* is hydrogen or a methyl group.

[Example 1-7] Preparation of monomer represented by the following chemical formula 5g

A monomer represented by the following formula (5g) was produced in the same manner as in Example 1-1, except that 19.4 g of bicyclohexane-4,4'-dione was used instead of 9.8 g of cyclopentane-1,3-dione. Obtained in% yield {H-NMR: i) R ^* = H, d (6.20, 2H), m (6.01, 2H), d (5.80, 2H), m (4.96, 2H), m (4.38, 4H ), m (4.21, 4H), m (1.35, 18H) ii) R ^* = CH ₃ , s (6.15, 2H), d (5.58, 2H), m (4.49, 2H), m (4.28, 4H) , m (3.86, 4H), m (1.55, 24H)}.

In Formula 5g, R ^* is hydrogen or a methyl group.

[Example 1-8] Preparation of monomer represented by the following formula (5h)

Except for using 9.8 g of cyclopentane-1,3-dione, 20.8 g of bis-4-oxo-cyclohexyl methane was used in the same manner as in Example 1-1 to give 50% of the monomer represented by Formula 5h. Yield {H-NMR: i) R ^* = H, d (6.20, 2H), m (6.01, 2H), d (5.80, 2H), m (4.96, 2H), m (4.38, 4H), m (4.21, 4H), m (1.35, 20H) ii) R ^* = CH ₃ , s (6.15, 2H), d (5.58, 2H), m (4.49, 2H), m (4.28, 4H), m (3.86, 4H), m (1.55, 26H)}.

In Formula 5h, R ^* is hydrogen or a methyl group.

Example 1-9 Preparation of Monomers Represented by Formula 5i

A monomer represented by the following Chemical Formula 5f was obtained in a yield of 50% in the same manner as in Example 1-5 except for using 31.2 g of normalpentane-1,3,5-triol instead of 24.0 g of glycerol {H- NMR: i) R ^* = H, d (6.43, 2H), m (6.05, 2H), d (5.80, 2H), m (4.15, 4H), m (3.80, 6H), m (1.35, 20H) ii) R ^* = CH ₃ , s (6.15, 2H), d (5.58, 2H), m (4.15, 4H), m (3.80, 6H), m (2.02, 26H)}.

In Formula 5i, R ^* is hydrogen or a methyl group.

Example 2-1 Preparation of Polymer Represented by Chemical Formula 3a

35.8 g (0.1 mol) of monomers (R ^* = methyl group), 22.2 g (0.1 mol) of 2-methyl-2-adamantyl methacrylate and azobis (isobutyronitrile) ( 0.7 g of AIBN) was added, the reaction was dissolved in 25 g of anhydrous THF, gas was removed using an ampoule as a freezing method, and the gas-free reaction was polymerized at 68 ° C. for 24 hours. After the polymerization was completed, the precipitate was slowly added dropwise to an excess of diethyl ether, followed by precipitation. The precipitate was dissolved again with THF, and the reactant was reprecipitated in diethyl ether to give a polymer represented by Chemical Formula 3a. R ^* and R ^** = methyl group, x = 1, y = 1) were prepared (molecular weight: 15,200, dispersion degree: 2.32).

Example 2-2 Preparation of the Polymer Represented by Chemical Formula 3b

And it is carried out except instead of the monomer (R ^* = methyl) 35.8g (0.1mol) of the formula 5a was used to form the monomer (R ^* = methyl) 37.2g (0.1mol) of the formula 5b Example 2 In the same manner as in 1, the polymer represented by Chemical Formula 3b (R ^* and R ^** = methyl group, x = 1, y = 1) was prepared (molecular weight: 12,500, dispersion degree: 2.12).

Example 2-3 Preparation of Polymer Represented by Chemical Formula 3c

Example 2- except that 42.8 g (0.1 mol) of the monomer (R ^* = methyl group) represented by Formula 5c was used instead of 35.8 g (0.1 mol) of the monomer (R ^* = methyl group) represented by Formula 5a. In the same manner as in 1, polymers represented by Chemical Formula 3c (R ^* and R ^** = methyl group, x = 1, y = 1) were prepared (molecular weight: 9,200, dispersion degree: 1.89).

Example 2-4 Preparation of the Polymer Represented by Chemical Formula 3d

Example 2- except that 41.2 g (0.1 mol) of the monomer (R ^* = methyl group) represented by Formula 5d was used instead of 35.8 g (0.1 mol) of the monomer (R ^* = methyl group) represented by Formula 5a. A polymer represented by Chemical Formula 3d (R ^* and R ^** = methyl group, x = 1, y = 1) was prepared in the same manner as 1 (molecular weight: 10,900, dispersion degree: 1.96).

Example 2-5 Preparation of the Polymer Represented by Chemical Formula 3e

Example 2- except that 42.4g (0.1mol) of monomer (R ^* = methyl group) represented by Formula 5e was used instead of 35.8g (0.1mol) of monomer (R ^* = methyl group) represented by Formula 5a In the same manner as in 1, polymers represented by Chemical Formula 3e (R ^* and R ^** = methyl group, x = 1, y = 1) were prepared (molecular weight: 9,200, dispersion degree: 2.12).

Example 2-6 Preparation of the Polymer Represented by Chemical Formula 3f

Example 2- except that 53.6 g (0.1 mol) of the monomer (R ^* = methyl group) represented by Formula 5f was used instead of 35.8 g (0.1 mol) of the monomer (R ^* = methyl group) represented by Formula 5a. In the same manner as in 1, polymers represented by Chemical Formula 3f (R ^* and R ^** = methyl group, x = 1, y = 1) were prepared (molecular weight: 9,680, dispersion degree: 2.08).

Example 2-7 Preparation of Polymer Represented by Chemical Formula 3g

Example 2- except that 49.4 g (0.1 mol) of monomer (R ^* = methyl group) represented by Formula 5g was used instead of 35.8 g (0.1 mol) of monomer (R ^* = methyl group) represented by Formula 5a. A polymer represented by Chemical Formula 3g (R ^* and R ^** = methyl group, x = 1, y = 1) was prepared in the same manner as 1 (molecular weight: 9,210, dispersion degree: 2.13).

Example 2-8 Preparation of the Polymer Represented by Chemical Formula 3h

Example 2- except that 50.8g (0.1mol) of monomer (R ^* = methyl group) represented by Formula 5h was used instead of 35.8g (0.1mol) of monomer (R ^* = methyl group) represented by Formula 5a A polymer represented by Chemical Formula 3h (R ^* and R ^** = methyl group, x = 1, y = 1) was prepared in the same manner as 1 (molecular weight: 9,210, dispersion degree: 2.13).

[Examples 3-1 to 3-8] Preparation of a photoresist composition comprising the polymer prepared in Examples 2-1 to 2-8

2 g of the polymer prepared in Example 2-1, 0.024 g of phthalimidotrifluoromethanesulfonate and 0.06 g of triphenylsulfonium triflate were dissolved in 20 g of propylene glycol monomethyl ether acetate, followed by filtration with a 0.20 µm filter. A resist composition was prepared (Example 3-1). On the other hand, instead of the polymer 2g prepared in Example 2-1, except that the polymer 2g prepared in Examples 2-2 to 2-8 was used to prepare a photoresist composition in the same manner (Example 3 -2 to 3-8).

[Examples 4-1 to 4-8] Exposure pattern formation using photoresist composition

After spin-coating the photoresist composition prepared in Examples 3-1 to 3-8 on the etched layer of the silicon wafer to prepare a photoresist thin film, soft bake for 90 seconds in an oven or hot plate at 90 ° C., After exposure with an ArF laser exposure equipment, the substrate was heated again at 120 ° C. for 90 seconds. The heated wafer was immersed in a 2.38 wt% TMAH aqueous solution for 40 seconds to develop, thereby forming an L / S (Line / Space) pattern of 0.07 μm. Physical properties of the formed photoresist pattern are shown in Table 1 below, and electron scanning micrographs of the photoresist patterns formed using the compositions prepared in Examples 3-1 to 3-8 are shown in FIGS. 1 to 8, respectively.

Resist composition Resolution [μm] Depth of focus [μm] Line Edge Roughness [nm] Energy process margin [%] Post-exposure Bake Temperature Stability [nm / ℃] Dry etching resistance Example 3-1 0.065 0.30 5.5 12.0 6 Great Example 3-2 0.065 0.30 5.5 12.5 4 Great Example 3-3 0.065 0.35 4.7 15.0 One Great Example 3-4 0.065 0.45 4.5 13.0 2 Very good Example 3-5 0.065 0.45 4.5 13.5 One Very good Example 3-6 0.065 0.30 4.5 11.0 3 Great Example 3-7 0.065 0.40 4.0 12.0 2.5 Great Example 3-8 0.065 0.35 4.6 12.5 3.5 Great

The photoresist monomer, polymer and photoresist composition comprising the same for the photoresist having a spiro cyclic ketal group according to the present invention have a low activation energy for the reaction in which the spiro cyclic ketal group is deprotected, thereby improving the resolution and process flexibility of the resist pattern. In addition, since it has high dry etching stability and stable post-exposure bake temperature stability, there is an advantage that a precise pattern can be realized. In addition, the photoresist polymer and the photoresist composition including the same may improve the depth of focus margin and line edge roughness of the resist film.

Claims (11)

Monomer represented by following formula (1). [Formula 1]

In Formula 1, R ^* is hydrogen or a methyl group, x and y are 1, 2 or 3, R is a mono-cyclic or multi-cyclic homo or hetero having 3 to 50 carbon atoms It is a saturated hydrocarbon group. The method of claim 1, wherein R is

,

,

,

,

,

,

,

,

,

,

And

Monomer selected from the group consisting of. The monomer of claim 1, wherein the monomer is prepared by reacting a cyclic ketone with a trialcohol under an acid catalyst. A photoresist polymer comprising a repeating unit represented by the following formula (2). [Formula 2]

In Formula 2, R ^* , R, x and y are as defined in Formula 1. The polymer for photoresist according to claim 4, wherein the photoresist polymer is represented by the following Chemical Formula 3. [Formula 3]

In Formula 3, R ^* and R ^** are each independently hydrogen or a methyl group, R ₁ is each independently a chain or cyclic alkyl group having 1 to 20 carbon atoms, a and b are repeats constituting the upper and lower polymer chains 5 to 95 mol% and 5 to 95 mol%, respectively, as the mole% of the unit, x, y and R are as defined in the formula (1). The photoresist polymer of claim 4, wherein the photoresist polymer is selected from the group represented by the following Chemical Formulas 3a to 3h. [Formula 3a]

[Formula 3b]

[Formula 3c]

[Formula 3d]

[Formula 3e]

[Formula 3f]

[Formula 3g]

[Formula 3h]

In Formulas 3a to 3h, R ^* , R ^** , R, R ₁ , a, b, x and y are as defined in Formula 3 above. A polymer including a repeating unit represented by Formula 2; Photoacid generators generating acid; And Photoresist composition comprising an organic solvent. The photoresist composition of claim 7, wherein the photoresist composition comprises 1 to 30 wt% of the polymer based on the total photoresist composition, 0.05 to 10 wt% of the photoacid generator and the remaining organic solvent based on the polymer. The method of claim 7, wherein the photoacid generator is phthalimidotrifluoromethanesulfonate, dinitrobenzyltosylate, n-decyldisulfone, naphthylimidotrifluoromethanesulfonate, diphenyl iodo salt hexafluorophosphate, Diphenylurodoxyl hexafluoro arsenate, diphenylurodoxyl hexafluoro antimonate, diphenylparamethoxyphenylsulfonium triflate, diphenylparatoluenylsulfonium triflate, diphenylparaisobutylphenylsulfonium tri Plates, triphenylsulfonium hexafluoro arsenate, triphenylsulfonium hexafluoro antimonate, triphenylsulfonium triflate, dibutylnaphthylsulfonium triflate and mixtures thereof Phosphorus photoresist composition. 8. The organic solvent of claim 7, wherein the organic solvent is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol, propylene. Glycol monoacetate, toluene, xylene, methyl ethyl ketone, methyl isoamyl ketone, cyclohexanone, dioxane, methyl lactate, ethyl lactate, methylpyruvate, ethylpyruvate, methylmethoxypropionate, ethyl Ethoxy propionate, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl 2-pyrrolidone, 3-ethoxyethylpropionate, 2-heptanone, gamma-butyrolactone Ethyl 2-hydroxypropionate, 2-hydroxy ethyl methyl propionate, ethyl ethoxy acetate, ethyl hydroxy acetate, 2-hydroxy methyl methyl butyrate, 3-methoxy 2-methylpropion The composition for photoresists selected from the group consisting of methyl acid, ethyl 3-ethoxypropionate, ethyl 3-methoxy 2-methylpropionate, ethyl acetate, butyl acetate and mixtures thereof. A photoresist polymer comprising a repeating unit represented by Formula 2; Photoacid generators generating acid; And applying a photoresist composition comprising an organic solvent to the substrate to form a photoresist film. And Exposing the photoresist film in a predetermined pattern; and then heating and developing the exposed photoresist pattern after exposure.

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