KR100931924B1 - Copolymer for chemically amplified photoresist comprising a 5-hydroxy-1-adamantyl (meth) acrylate derivative and a chemically amplified photoresist composition comprising the same - Google Patents

Abstract

The present invention is a copolymer for chemically amplified photoresist represented by the following formula (1) and a chemically amplified photoresist composition comprising the same, the chemically amplified photoresist using the polymer of the present invention is 5-hydroxy-1-adama The glass transition temperature is lowered by the R4 group in the repeating unit o in the main chain, including the methyl (meth) acrylate derivative, which not only has excellent resolution in both the C / H pattern and the L / S pattern, but also the excellent process window. ), An excellent pattern profile can be obtained regardless of the substrate type.

[Formula 1]

Wherein R ₁ , R ₂ , R _{3 ,} R _{4 ,} R ₅ , R ₆ , and R ₇ are independent of each other, and R ₁ , R _{2 ,} R ₃ represent a hydrogen atom, an ether group, an ester group, a carbonyl group, Carbon atoms with or without an acetal group, an epoxy group, a nitrile group, or an aldehyde group represent from 1 to 30 alkyl groups. R <_{5> ,} R <_6> , R <_7> is respectively independently hydrogen or a methyl group, and R <_4> is an acetyl group or a trihaloacetyl group. l, m, n, o are the numbers of repeating units in the main chain, respectively, l + m + n + o = 1, 0.1≤l / (l + m + n + o) ≤0.5, 0.1≤m / (l + m + n + o) ≦ 0.7, 0.1 ≦ n / (l + m + n + o) ≦ 0.7, and 0 <o / (l + m + n + o) ≦ 0.5.

Chemically amplified photoresist, chemically amplified photoresist, 5-hydroxy-1-adamantyl (meth) acrylate derivative

Description

Copolymer for chemically amplified photoresist comprising a 5-hydroxy-1-adamantyl (meth) acrylate derivative and a chemically amplified photoresist composition comprising the same {The copolymer containing 5-hydroxy-1-adamantyl (meth ) acrylate derivatives and their resist compositions}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer having enhanced adhesion and resolution in the patterning of photoresists, and a chemically amplified photoresist composition containing the same, and more particularly to 5-hydroxy-1 in a photoresist copolymer. -Chemical amplification type suitable for thermal flow process that can control line edge roughness, resolution, and glass transition temperature, including adamantyl (meth) acrylate derivative, and realize fine line resolution. It relates to a copolymer for photoresist and a chemically amplified photoresist composition comprising the same.

Recently, due to the high integration of semiconductor devices, ultra-fine patterns of 0.10 microns or less are required for the manufacture of ultra-LSI, so that the exposure wavelength is further shortened in the g- and i-ray regions used in the prior art, and thus far-infrared and KrF Attention has been paid to lithography using excimer lasers, ArF excimer lasers, EUV, X-rays and electron beams. In particular, ArF excimer laser is the most popular light source for lithography that requires the pattern of next generation 0.10 micron or less.In recent years, it has been developed from the existing ArF dry exposure technology, and high index material is used to realize the pattern below 45nm node. The introduction of the immersion technique used enables the implementation of ultra fine patterns.

Such a photoresist composition is composed of a component having an acid sensitive functional group (hereinafter referred to as "polymer"), a component which generates an acid by irradiation (hereinafter referred to as "photoacid generator"), a basic additive, and a solvent.

In the case of the polymer used as the main raw material of the photoresist, it should contain functional groups having proper affinity with the developer, adhesion with the substrate, etching resistance and excellent resolution.

Specific examples of such functional groups include hydroxy groups, lactone groups, carboxyl groups, and the like for improving affinity with a developer and adhesion to a substrate. Examples of functional groups that improve etching resistance include norbornene derivatives and ah. And compounds having a cyclic alkyl group having no oxygen atom in the main chain such as a tan derivative. However, in order to improve the resolution, there is a greater weight on the fluidity of the acid by the photoacid generator in terms of the structure of the polymer rather than a special functional group.

In addition to the above essential properties of the composition of the photoresist, the physical properties of the resist may include the glass transition temperature (Tg) of the polymer. Depending on the glass transition temperature, the pattern and contrast of the resist, particularly the thermal flow characteristics, will vary.

Until recently, many inventions have been advanced to satisfy such physical properties. Specifically, for example, a copolymer of adamantyl acrylate and cyclolactone acrylate [SPIE (1997, 3049 , 519) or USP 6,013,416], maleic hydride and olefin copolymer [SPIE (1996, 2724 , 355)] . Pure olefin copolymers [SPIE (1997, 3049 , 92)] hybrid copolymers synthesized by mixing their monomers [SPIE (1997, 3049 , 85), USP 6,677,419 B1, KR Application No .: 2004-2526] Etc. can be mentioned.

However, although the improvement of physical properties by these various technologies is constantly being made, there is a demand for a resist having a higher resolution even further due to the miniaturization of semiconductor chips, and at the same time, line edge roughness is the most important technology in achieving high resolution. It is one of the physical properties.

Accordingly, an object of the present invention is a chemically amplified photoresist that is sensitive to KrF excimer laser, ArF excimer laser, EUV, or e-Beam, etc., which has little dependence on the substrate, excellent transparency in the wavelength range, sensitivity, resolution and development. It is necessary to develop a photoresist pattern by developing a resin having a glass transition temperature which is excellent in thermal properties and particularly suitable for the thermal flow process, which is one of the resolution enhancement techniques (RET). It is to provide a resist composition.

Another object of the present invention is to provide a method of forming a photoresist pattern using the chemically amplified photoresist composition.

In order to achieve the above object, the present invention provides a chemically amplified photoresist polymer represented by the following formula (1).

Wherein R _1, R _2, R _3, R _4, R _5, R _6, and R ₇ is R _1, written to be independent of each other, R _2, R ₃ is a hydrogen atom, an ether group, an ester group, a carbonyl group, Carbon atoms with or without an acetal group, an epoxy group, a nitrile group, or an aldehyde group represent from 1 to 30 alkyl groups. R <_5>, R <_6> , R <_7> is respectively independently hydrogen or a methyl group, and R <_4> is an acetyl group or a trihalo acetyl group. l, m, n, o are the numbers of repeating units in the main chain, respectively, l + m + n + o = 1, 0.1≤l / (l + m + n + o) ≤0.5, 0.1≤m / (l + m + n + o) ≦ 0.7, 0.1 ≦ n / (l + m + n + o) ≦ 0.7, and 0 <o / (l + m + n + o) ≦ 0.5.

The chemically amplified photoresist composition of the present invention includes a copolymer, an acid generator, an additive, and a solvent represented by Chemical Formula 1.

Hereinafter, the present invention will be described in more detail.

polymer

The polymer for a photoresist composition for chemically amplified photoresists according to the present invention is represented by the following formula (1).

[Formula 1]

Wherein R _1, R _2, R _3, R _4, R _5, R _6, and R ₇ is R _1, written to be independent of each other, R _2, R ₃ is a hydrogen atom, an ether group, an ester group, a carbonyl group, Carbon atoms with or without an acetal group, an epoxy group, a nitrile group, or an aldehyde group represent from 1 to 30 alkyl groups. R <_5>, R <_6> , R <_7> is respectively independently hydrogen or a methyl group, and R <_4> is an acetyl group or a trihalo acetyl group. l, m, n, o are the numbers of repeating units in the main chain, respectively, l + m + n + o = 1, 0.1≤l / (l + m + n + o) ≤0.5, 0.1≤m / (l + m + n + o) ≦ 0.7, 0.1 ≦ n / (l + m + n + o) ≦ 0.7, and 0 <o / (l + m + n + o) ≦ 0.5.

Preferred examples of the photoresist polymer according to the present invention include polymers represented by the following general formulas (2a to 2l).

The polymer for chemically amplified photoresist composition represented by Chemical Formula 1 may be a hydroxy adamantyl (meth) having a acetyl group or a trihalo acetyl group introduced by an esterification reaction to a (meth) acrylate derivative, a norbornene derivative, or a hydroxy group. ) Has a derivative of acrylate as a repeating unit.

In the above structural formula, the norbornene functional group of the norbornene derivative represented by the repeating unit l has a property of leading to a copolymer having a modified helical structure, so that the solubility with a solvent of the conventional (meth) acrylate copolymer is good. I was able to improve greatly.

The repeating unit represented by l is used in 10 mol% to 50 mol% of all monomers, preferably 20 mol% to 40 mol%.

The repeating unit represented by m is used in 10 mol%-70 mol% of all monomers.

The repeating unit represented by n is used in 10 mol%-70 mol% of all monomers.

In addition, when copolymerizing only (meth) acryl, it is difficult to control the molecular weight and it is not easy to prepare a polymer having a relatively low molecular weight, but when introducing norbornene derivatives such as the above formula into the polymerization reaction, the degree of polymerization of (meth) acryl Compared to the case where no norbornene derivatives were used, a polymer having a relatively low molecular weight could be prepared, and as a radical quencher, it was able to act as a molecular weight regulator and improve etching resistance.

In the repeating unit o, the hydroxy group of 5-hydroxy-1-adamantyl (meth) acrylate is introduced into the acetyl group or the trihalo acetyl group by esterification. By improving the line edge roughness of the resist, the effect of lowering the glass transition temperature, which greatly affects the physical properties of the polymer, is significantly lower than when polymerized using only hydroxy adamantyl (meth) acrylate. Could.

The repeating unit represented by o is used in more than 0 mol%-50 mol% or less of all monomers, Preferably it is 10 mol%-40 mol%.

When the trihalo acetyl group is introduced, the amount of substitution is appropriately adjusted in the hydroxy group to prepare a polymer having low additive elution in the resist with respect to water currently used in the ArF immersion exposure method. It was possible to develop a resin that can be used for resists that can be used for immersion lithography without use.

Conventional (meth) acrylate polymers have poor solubility in solvents, are difficult to control the glass transition temperature, and are difficult to properly use as resists due to disadvantages such as low etching resistance. In addition, the copolymer of cyclic olefin and maleic hydride has a high light absorption property in maleic hydride at 193 nm, and thus the permeability is not good, resulting in deterioration of perpendicularity to the pattern and reduction of resolution. Despite the efforts, it is difficult to apply to device processing.

However, in the present invention, by introducing the ester group, the line edge roughness of the resist made of this polymer is better, and at the same time, the glass transition temperature can be freely controlled by controlling the substitution amount of the acetyl group or the trifluoro acetyl group.

Therefore, the relatively low glass transition temperature (Tg) required in the thermal flow process, which is one of the techniques for obtaining high resolution in the C / H pattern implementation, is one of the pattern implementation methods of the resist. In addition, the ArF immersion exposure method uses a technique of increasing the refractive index by using water on the exposed wafer and the resist-coated wafer in order to obtain a high aperture ratio, without leaching to the resist caused by water without a top coat material. It is possible to prevent the polymer which has a great effect on the development of resist used for immersion exposure method without top coat material.

In PAG (Triphenylsulfonium nonaflate) used as a photoacid generator, the PAG having introduced a norbornene derivative and a cyclic alkyl group into the anion part of the sulfonium salt is used, and the diffusion length in the resist coating is relatively higher than that of the conventional PAG. Appropriately short, there was a big advantage in the high resolution of the resist.

The polymer obtained in the present invention is generally insoluble to poorly soluble in aqueous alkali solution, but may be soluble in some cases. In addition, the polymer has an acid labile functional group in the side chain portion but may not have a functional group in some cases.

Depending on the type and content of monomers in the polymer, their solubility may increase or decrease. In general, as the hydrophobic group increases, solubility in aqueous alkali solution decreases. Thus, a photoresist composition excellent in substrate adhesion, substrate independence, sensitivity, and resolution in a resist using a polymer obtained by adjusting the type and content of monomers can be obtained.

Such multipart copolymers may be block copolymers, random copolymers or graft copolymers.

Polymerization method of the polymer represented by the formula (1) can be polymerized by a conventional method, but radical polymerization is preferred. Radical polymerization initiators are common such as azobisisobutyronitrile (AIBN), benzoyl peroxide (BPO), lauryl peroxide, azobisisocapronitrile, azobisisovaleronitrile, and t-butyl hydroperoxide. There is no particular limitation as long as it is used as a radical polymerization initiator.

The polymerization method can be carried out by bulk polymerization, solution polymerization, suspension polymerization, bulk suspension polymerization, emulsion polymerization, etc.The polymerization solvent is benzene, toluene, xylene, halogenated benzene, diethyl ether, tetrahydrofuran, esters, etc. At least one selected from ethers, lactones, ketones, amides and alcohols.

The polymerization temperature is appropriately selected and used depending on the type of catalyst. The molecular weight distribution of the polymer can be appropriately adjusted by changing the amount of use of the polymerization initiator and the reaction time. It is preferable to remove the unreacted monomers and by-products remaining in the reaction mixture after the polymerization is completed by precipitation with a solvent.

The polystyrene reduced weight average molecular weight (hereinafter referred to as "Mw") by gel permeation chromatography (GPC) of the polymer is generally 2,000 to 1,000,000, and 3,000 to 1,000, considering the sensitivity, developability, applicability, and heat resistance as a photoresist. 50,000 is preferred. 1.0-5.0 are preferable and, as for the molecular weight distribution of a polymer, 1.0-3.0 are especially preferable.

The chemically amplified photoresist composition of the present invention includes a copolymer, an acid generator, an additive, and a solvent represented by Chemical Formula 1.

The content of the copolymer may include 3% by weight to 20% by weight of one or more polymers selected from the copolymers represented by Formula 1 based on the total composition of the resist.

If the content is less than 3% by weight, the viscosity in the composition is too low to form a film of the desired thickness, there is a problem that the pattern loss is severe by a relatively many acid generators. If the content is more than 20% by weight, the film thickness is too thick, there is a problem that the transmittance of radiation is poor and it is difficult to obtain a vertical pattern.

Acid generator

Acid generators used in the composition of the present invention may be used onium salt-based iodonium salts (iodonium salts), sulfonium salts (sulfonium salts), phosphonium salts, diazonium salts, pyridinium salts, and imides Preferably, the sulfonium salt represented by following formula (3) or (4) can be used. Most preferably, norbornene and a cyclic alkyl group are introduced into the anion so that the diffusion length of the acid in the resist film is kept short appropriately to obtain a high resolution of the resist.

In Formulas 3 and 4, R ₁ and R ₂ each independently represent an alkyl group, an allyl group, a perfluoroalkyl group, a benzyl group, or an aryl group, and R ₃ , R _4, and R ₅ represent hydrogen, an alkyl group, or a halogen group. , Alkoxy group, aryl group, thiophenoxy, thioalkoxy, or alkoxycarbonylmethoxy group,

A of the anion moiety is OSO ₂ CF ₃ , OSO ₂ C ₄ F _{9 ,} OSO ₂ C ₈ F _{17 ,} N (CF ₃ ) _2, N (C ₂ F ₅ ) _2, N (C ₄ F ₉ ) _2, C (CF ₃ ) _3, C (C ₂ F ₅ ) _3, C (C ₄ F ₉ ) _3, a compound represented by the formula 5a, 5b, 5c, 5d, or 5d.

The acid generator is used in 0.3 parts by weight to 10 parts by weight with respect to 100 parts by weight of the polymer solid content, preferably from 1 part by weight to 8 parts by weight. When used in excess of 10 parts by weight, the verticality of the pattern is remarkably inferior, and when used in less than 0.3 parts by weight, there is a problem in that the flexibility of the pattern is deteriorated. Said acid generator may be used individually or in mixture of 2 or more types.

additive

In the present invention, if necessary, a compound which is decomposed by an acid to promote dissolution in a developer may be used. Compounds which are decomposed by an acid to promote dissolution in a developing solution are alicyclic derivatives having a functional group which can be easily decomposed by an acid such as t-butyl ester or alkoxyalkanyl ester.

The amount of the compound used is 2 to 60 parts by weight, preferably 5 to 20 parts by weight based on 100 parts by weight of the total solid component.

The resist composition of the present invention may be included as an additive such as a surfactant, an anti-halation agent, an adhesion aid, a storage stabilizer, an antifoaming agent and the like as necessary. It will not specifically limit, if these specific compounds are contained in a normal photoresist composition.

In addition, a basic compound may be used to prevent diffusion of acid generated after exposure. Since the basic compound has a disadvantage in that the sensitivity decreases as the amount used increases, it should be used properly according to the basicity.

The amount of the basic compound added is suitably used in an amount of 0.01 to 5 parts by weight based on the total solid component. If the amount of the basic compound is more than 5 parts by weight, the sensitivity is lowered. If the amount of the basic compound is less than 0.01 parts by weight, the effect increases depending on the delay time after exposure, thereby affecting the shape of the pattern.

menstruum

In order to obtain a uniform and flat coating film, the resist composition of the present invention is used after being dissolved in a solvent having an appropriate evaporation rate and viscosity. Solvents having these properties include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether Acetate, propylene glycol monopropyl ether acetate, methyl isopropyl ketone, cyclohexanone, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, 2-heptanone, ethyl lactate, γ-butyrolactone, and the like. In some cases, these alone or two or more kinds of mixed solvents are used.

The amount of the solvent is adjusted to be uniformly formed on the wafer using an appropriate amount depending on the physical properties of the solvent, that is, volatility, viscosity, and the like.

Using the chemically amplified photoresist composition according to the present invention, a photoresist pattern may be formed by the following method.

The composition of the present invention is prepared in the form of a solution, applied on a wafer substrate and dried to form a photoresist coating film. At this time, as a coating method on a substrate, a resist solution is prepared and filtered, and then the solution can be applied onto the substrate by a method such as rotary coating, spill coating or roll coating.

Radiation is partially irradiated to form a fine pattern on the photoresist film. At this time, the radiation to be used is not particularly limited, and may be selectively used depending on the type of acid generator as I-ray which is ultraviolet ray, KrF excimer laser which is far ultraviolet ray, ArF excimer laser, X-ray, electron beam which is charged particle beam and the like.

In the last step after irradiation, the exposed photoresist pattern is developed.

Developers used for development include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium methane silicate, ammonia water, ethylamine, n-propylamine, triethylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide It selects from aqueous solution containing a seed etc., and uses, Preferably tetramethylammonium is used. If necessary, surfactants, water-soluble alcohols and the like may be used as additives.

The copolymer for chemically amplified photoresist and the chemically amplified photoresist composition comprising the same according to the present invention include a 5-hydroxy-1-adamantyl (meth) acrylate derivative in a line for the photoresist copolymer. It is easy to control line edge roughness, resolution, and glass transition temperature, and a thermal flow process that can realize fine line resolution can be applied.

Hereinafter, the present invention will be specifically described as the following Synthesis Examples and Examples. However, the present invention is not limited to the synthesis examples and examples.

Monomer Synthesis

Synthesis Example 1 Synthesis of 3-acetoxy, 1-adamantyl acrylate

In a three-necked round flask equipped with a stirrer and a reflux condenser, 30 g of 3-hydroxy, 1-adamantyl acrylate (3-Hydroxy, 1-adamantyl acrylate) and 17.8 g of acetic anhydride were diluted with dichloromethane. (dichloromethane) was dissolved in 300 g and stirred.

13.8 g of pyridine was slowly added dropwise to the oil bath while increasing the temperature to the temperature at which dichloromethane was refluxed. After the addition, add 1 g of 4-dimethyl aminopyridine to the reaction solution and stir at reflux for 3 hours. The end point of the reaction was confirmed by thin layer chromatography, and the reaction was neutralized with 2% hydrochloric acid solution (2% HCl solution).

After distilled water was added and extracted three times with dichloromethane, the organic layer was removed in a vacuum distillation apparatus, and then dissolved in n-nucleic acid (n-Hexane) to recrystallize to give 28.5g.

The structure of the product was confirmed by 300M ¹ H NMR.

Synthesis Example 2 Synthesis of 3-trifluoroacetoxy, 1-adamantyl methacrylate (3-tirfluoro acetoxy, 1-adamantyl methacrylate)

In a three-necked round flask equipped with a stirrer and a reflux condenser, 30 g of 3-hydroxy 1-adamantyl methacrylate and 34.7 g of trifluoroacetic anhydride were added. It was dissolved in 300 g of dichloromethane and stirred.

13.8 g of pyridine is slowly added dropwise to the base catalyst. After the dropwise addition, 1 g of 4-dimethyl aminopyridine was added to the reaction solution, and the mixture was stirred while refluxing for 3 hours. The end point of the reaction is confirmed by thin layer chromatography, and the reaction is neutralized with 2% hydrochloric acid solution (2% HCl solution).

After distilled water was added and extracted three times with dichloromethane, the organic layer was removed by depressurization distillation apparatus, and then dissolved in n-nucleic acid (n-Hexane) to recrystallize to obtain 30g.

The structure of the product was confirmed by 300M ¹ H NMR.

Synthesis Example 3 Synthesis of 3 -acetoxy 1-adamantyl methacrylate (3-acetoxy, 1-adamantyl methacrylate)

In a three-neck round flask equipped with a stirrer and a reflux condenser, 30 g of 3-hydroxy 1-adamantyl methacrylate and 16.8 g of acetic anhydride were diluted with dichloromethane. (dichloromethane) was dissolved in 300 g and stirred. 13.8 g of pyridine was slowly added dropwise as a base catalyst.

After the dropwise addition, 1 g of 4-dimethyl aminopyridine was added to the reaction solution, and the mixture was stirred while refluxing for 3 hours. The end point of the reaction is confirmed by thin layer chromatography, and the reaction is neutralized with 2% hydrochloric acid solution (2% HCl solution).

After distilled water was added and extracted three times with dichloromethane, the organic layer was removed by depressurization distillation apparatus, and then dissolved in n-nucleic acid (n-Hexane) to recrystallize to obtain 28g.

The structure of the product was confirmed by 300M ¹ H NMR.

Polymer Synthesis

Synthesis Example 4 Formula 2 chemical amplification represented by a For photoresist  Polymer manufacturing

Polymerization monomer norbornene, 1-methyl 1-adamantly acrylate, 1-methyl adamantly acrylate, c-butyrolactone methacrylate, 3-acetoxy-1-a 9.4g / 22.0g / 17.0 / 29.4g each of 3-mantoxy methacrylate (3-acetoxy-1-adamantyl methacrylate) was added, 3.6g of AIBN as a polymerization initiator and 1,4-dioxane (1,4-dioxane as a polymerization solvent). 156g) was stirred for 1 hour at room temperature under nitrogen gas injection.

The temperature of the reactor was maintained at 65 ^o C and the reaction was carried out for 16 hours, and then the solution was cooled to room temperature. The reaction solution cooled to room temperature was filtered after precipitation to the nucleic acid. In the case of filtration, after washing several times with the same solvent and drying under reduced pressure, 61 g of the following polymer formula (1) was obtained.

Polystyrene reduced weight-average molecular weight (Mw) of 9630, ratio Mw / Mn = 2.0 was the glass transition temperature (Tg) of the weight average molecular weight to the number average molecular weight of the polymer was 133.0 ^o C.

The polymer structure was confirmed by 300M ¹ H NMR, shown in FIG. 1. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 11 and the glass transition temperature (Tg) is shown in FIG. 21.

[Formula 2a]

Synthesis Example 5 Formula 2 chemical amplification represented by e For photoresist  Polymer manufacturing

Monomer bicyclo [2.2.1] heptene-2-propanoic acid, beta-hydroxy, 1,1-dimethylethyl ester for polymerization (Bicyclo [2.2.1] hept-5-ene-2-propanoic acid, b- hydroxy-, 1,1-dimethylehtyl ester, hereinafter referred to as BHP), 1-methyl 1-adamantyl acrylate, gamma-butyrolactone acrylate, 3acetoxy-1-adamantyl acrylate was added 23.8g / 22.0g / 17.0g / 29.4g each to 3.6g AIBN as polymerization initiator and 1,4 as polymerization solvent. -185 g of dioxane (1,4-dioxane) was added thereto, followed by stirring for 1 hour at room temperature under nitrogen gas injection.

The temperature of the reactor was maintained at 65 ^° C. and the reaction was carried out for 16 hours, after which the solution was cooled to room temperature. The reaction solution cooled to room temperature was filtered after precipitation to the nucleic acid. In the case of filtration, after washing several times with the same solvent and drying under reduced pressure, 84g of the polymer represented by the following formula (2e) was obtained.

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 9,890, and the ratio of weight average molecular weight to number average molecular weight Mw / Mn = 2.1 and glass transition temperature (Tg) was 124.0 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, shown in FIG. 2. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 12 and the glass transition temperature (Tg) is shown in FIG. 22.

[Formula 2e]

Synthesis Example 6 Formula 2 chemical amplification represented by b For photoresist  Polymer manufacturing

Monomer norbornene for polymerisation, 1-isopropyl 2-adamantyl methacrylate, c-butyrolactone acrylate, 3-acetoxy- 1-adamantyl methacrylate (3-acetoxy-1-adamantyl methacrylate) was added to 9.4 g / 26.2 g / 15.6 / 29.4 g, respectively, and 3.6 g of AIBN as the polymerization initiator and 1,4-dioxane as the polymerization solvent (1, 161 g of 4-dioxane) was added and polymerized in the same manner as in Synthesis Example 4) to obtain 55.6 g of the same compound as in the following formula (4).

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 10,000, the ratio of the weight average molecular weight to the number average molecular weight Mw / Mn = 1.77, and the glass transition temperature (Tg) was 136.3 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, and is shown in FIG. 3. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 13 and the glass transition temperature (Tg) is shown in FIG.

[Formula 2b]

Synthesis Example 7 Formula 2 chemical amplification represented by c For photoresist  Polymer manufacturing

Monomer for polymerization norbornene, 1-methyl 1-cyclopentyl acrylate, c-butyrolactone methacrylate, 3-acetoxy-1- Add 9.4 g / 15.4 g / 17 g / 29.4 g of adamantyl methacrylate (3-acetoxy-1-adamantyl methacrylate), respectively, and 3.6 g of AIBN as a polymerization initiator and 1,4-dioxane (1,4- as a polymerization solvent). 142 g of dioxane) was added and polymerized in the same manner as in Synthesis Example 4) to obtain 58.7 g of the same compound as in the following formula (4).

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 10,000, the ratio of the weight average molecular weight to the number average molecular weight Mw / Mn = 1.96, and the glass transition temperature (Tg) was 95.4 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, shown in FIG. 4. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 14, and the glass transition temperature (Tg) is shown in FIG. 24.

[Formula 2c]

Synthesis Example 8 Formula 2 chemical amplification represented by f For photoresist  Polymer manufacturing

Polymeric monomers BHP (Bicyclo [2.2.1] hept-5-ene-2-propanoic acid, b-hydroxy-, 1,1-dimethylehtyl ester), 1-isopropyl 2-adamantyl methacrylate (1- 23.8g / 26.2 isopropyl 2-adamantyl methacrylate, c-butyrolactone acrylate and 3-acetoxy-1-adamantyl methacrylate, respectively g / 15.6g / 29.4g each, 3.6g of AIBN as a polymerization initiator and 190g of 1,4-dioxane (1,4-dioxane) as a polymerization solvent, followed by polymerization in the same manner as in Synthesis Example 4) 69.3 g of the same compound as 6) was obtained.

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 9,510, the ratio of the weight average molecular weight to the number average molecular weight Mw / Mn = 2.00, and the glass transition temperature (Tg) was 105.8 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, and is shown in FIG. 5. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 15 and the glass transition temperature (Tg) is shown in FIG. 25.

[Formula 2f]

Synthesis Example 9 Formula 2 chemically amplified by g For photoresist  Polymer manufacturing

Monomers for polymerization norbornene, 1-methyl 1-adamantyl acrylate, c-butyrolactone methacrylate, 3-trifluoroace Add 9.4 g / 22.0 g / 17.0 g / 34.8 g of 3-trifluoroacetoxy-1-adamantyl methacrylate, respectively, and 3.6 g of AIBN as a polymerization initiator and 1,4-dioxane as a polymerization solvent. 166 g of (1,4-dioxane) was added thereto, followed by polymerization in the same manner as in Synthesis Example 4) to obtain 70 g of the same compound as in the following Chemical Formula (7).

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 9,400, and the ratio of weight average molecular weight to number average molecular weight Mw / Mn = 1.75 and glass transition temperature (Tg) was 118.4 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, and is shown in FIG. 6. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 16 and the glass transition temperature (Tg) is shown in FIG. 26.

[Formula 2g]

Synthesis Example 10 Formula 2 chemical amplification represented by h For photoresist  Polymer manufacturing

Polymer monomer norbornene, 1-isopropyl 2-adamantyl methacrylate, c-butyrolactone acrylate, 3-trifluoro Add 9.4 g / 26.2 g / 15.6 g / 34.8 g of acetoxy-1-adamantyl methacrylate, respectively, to 3.6 g of AIBN as a polymerization initiator and 1,4- as a polymerization solvent. 172 g of dioxane (1,4-dioxane) was added thereto, followed by polymerization in the same manner as in Synthesis Example 4) to obtain 75 g of the same compound as the following Chemical Formula (8).

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 10,800, and the ratio of weight average molecular weight and number average molecular weight Mw / Mn = 1.85 and glass transition temperature (Tg) were 145 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, shown in FIG. 7. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 17 and the glass transition temperature (Tg) is shown in FIG. 27.

[Formula 2h]

Synthesis Example 11 Formula 2 chemical amplification represented by i For photoresist  Polymer manufacturing

Polymeric monomers norbornene, 1-methyl cyclopentyl acrylate, 1-methyl 1-cyclopentyl acrylate, c-butyrolactone methacrylate, 3-trifluoroacetoxy-1 Add 9.4 g / 15.4 g / 17.0 g / 34.8 g each of 3-trifluoroacetoxy-1-adamantyl methacrylate and 3.6 g of AIBN as an initiator as a polymerization initiator and 152 g of 1,4-dioxane as a polymerization solvent. After the addition, the polymerization was carried out in the same manner as in Synthesis Example 4) to obtain 63 g of the same compound as the following polymer formula (9).

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 12,500, and the weight average molecular weight and number average molecular weight Mw / Mn = 1.62, and the glass transition temperature (Tg) was 108.3 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, shown in FIG. 8. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 18 and the glass transition temperature (Tg) is shown in FIG. 28.

[Formula 2i]

Synthesis Example 12 Formula 2 chemical amplification represented by k For photoresist  Polymer manufacturing

Polymeric monomers BHP (Bicyclo [2.2.1] hept-5-ene-2-propanoic acid, b-hydroxy-, 1,1-dimethylehtyl ester), 1-methyl 1-adamantyl acrylate (1-methyl adamantyl acrylate), c-butyrolactone methacrylate and 3-trifluoroacetoxy-1-adamantyl methacrylate (23.8 g / 22.0), respectively. g / 17.0g / 34.8g each was added, 3.6g of AIBN as a polymerization initiator and 195g of 1,4-dioxane as a polymerization solvent were added, followed by polymerization in the same manner as in Synthesis Example 4) to give 85g of a compound of the following Chemical Formula (10) Got it.

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 12,200, and the weight average molecular weight and number average molecular weight Mw / Mn = 1.58, and the glass transition temperature (Tg) was 141.3 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, shown in FIG. 9. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 19 and the glass transition temperature (Tg) is shown in FIG. 29.

[Formula 2k]

Synthesis Example 13 Formula 2 Chemical amplification type represented by l For photoresist  Polymer manufacturing

Polymeric monomers BHP (Bicyclo [2.2.1] hept-5-ene-2-propanoic acid, b-hydroxy-, 1,1-dimethylehtyl ester), 1-isopropyl 2-adamantyl methacrylate (1- 23.8 isopropyl 2-adamantyl methacrylate, c-butyrolactone acrylate and 3-trifluoroacetoxy-1-adamantyl methacrylate g / 26.2g / 15.6g / 34.8g each, add 3.6g of AIBN as a polymerization initiator and 200g of 1,4-dioxane (1,4-dioxane) as a polymerization solvent, and then polymerize in the same manner as in Synthesis Example 4). 89 g of the compound similar to the general formula (11) was obtained.

The polystyrene reduced weight average molecular weight (Mw) of this polymer was 12,800, and the weight average molecular weight and number average molecular weight Mw / Mn = 1.68, and the glass transition temperature (Tg) was 143 ^° C.

The polymer structure was confirmed by 300M ¹ H NMR, and is shown in FIG. 10. The gel permeation chromatogram (GPC) of the polymer is shown in FIG. 20 and the glass transition temperature (Tg) is shown in FIG. 30.

[Formula 2l]

<Resistor Preparation and Photoresist Pattern Comparison Evaluation of Examples and Comparative Examples>

Example 1 Resist Preparation

4 parts by weight of triphenyl sulfonium nonaplate as an acid generator and 0.5 parts by weight of tetramethyl ammonium hydroxide as basic additives based on 100 parts by weight of the resin obtained in Synthesis Example 4 (Formula 2a) 800 parts by weight of propylene glycol methyl ether acetate It was dissolved in and then filtered through a 0.2 μm membrane filter to prepare a resist.

The obtained resist liquid was applied to a substrate using a spinner, and dried at 110 ° C. for 90 seconds to form a film having a thickness of 0.25 μm. The formed film was exposed to light using an ArF excimer laser stepper (lens numerical aperture: 0.75), and then heat-treated at 120 ° C. for 90 seconds. Subsequently, it was developed, washed and dried for 40 seconds with an aqueous 2.38 wt% tetramethylammonium hydroxide solution to form a resist pattern.

The developability with respect to aqueous tetramethylammonium hydroxide solution and the adhesion of the formed resist pattern to the board | substrate were favorable, the resolution was 0.09 micrometer, and the sensitivity was 14 mJ / cm <2>.

In the case of LER, the roughness of the pattern was observed for the 0.13 µm line-and-space (L / S) pattern formed after development. 5 is indicated (the higher the number, the better LER).

In the case of sensitivity, the exposure amount which forms the 0.13 탆 line-and-space (L / S) pattern formed after development at a line width of one-to-one is the optimal exposure amount, and this optimal exposure amount is sensitivity, and the minimum pattern dimension resolved is called resolution. It was.

EXAMPLES 2-10

Using the resin (Formula 2a, 2e, 2g) obtained in Synthesis Example 4, 5, 9, the acid generator and the basic additive were dissolved in 800 parts by weight of propylene glycol methyl ether acetate, and then filtered through a 0.2 μm membrane filter to Table 1 After preparing the resist composition (however, parts are based on weight) to be displayed, the same procedure as in Example 11 was carried out to form a positive resist pattern, and various evaluations were performed. The evaluation results are shown in Table 1.

The adhesion and developability of the resist patterns obtained in each example were good, and the resulting resist patterns were heated to 130 ° C. on a hot plate to observe the degree of deformation of the patterns. As a result, there was no deformation and excellent heat resistance.

Resin (100 parts by weight) ^* PAG (parts by weight) ^* Base (parts by weight) Sensitivity (mJ / cm ² ) Resolution (nm) LER Example 2 Formula 2a 3.0 0.5 14 90 4 Example 3 Formula 2e 3.0 0.5 14 90 2 Example 4 Formula 2g 3.0 0.5 14 110 3 Example 5 Formula 2a 4.0 0.5 13 90 5 Example 6 Formula 2e 4.0 0.5 13 80 3 Example 7 Formula 2g 4.0 0.5 13 100 4 Example 8 Formula 2a 4.0 0.8 14 90 2 Example 9 Formula 2e 4.0 0.8 14 90 2 Example 10 Formula 2g 4.0 0.8 14 100 One Comparative Example 1 Formula 6 3.0 0.5 13 100 One Comparative Example 2 Formula 6 4.0 0.5 12 110 One Comparative Example 3 Formula 6 4.0 0.8 14 110 One

^* PAG: Triphenylsulfonium nonaflate, ^* Base: Tetramethylammonium hydroxide

Comparison of glass transition temperature (Tg) according to each formula Chemical formula Formula 2a Formula 2e Formula 2b Formula 2c Formula 2f Formula 2g Tg ( ^o C) 133 124 136 95 106 118 Chemical formula Formula 2h Formula 2i Formula 2k Formula 2l Formula 6 Tg ( ^o C) 145 108 141 143 181

Formulas 2a to 2l: Tg of the resin used in the examples,

Formula 6: Tg of the resin used in the comparative example

[Comparative Examples 1-3]

Next, using a polymer synthesized using 5-hydroxy-1-adamantyl methacrylate (5-hydroxy-1-adamantyl methacrylate) using a monomer which is not substituted with an acetyl group or a triacetyl acetyl group, An acid generator and a basic additive were dissolved in 800 parts by weight of propylene glycol methyl ether acetate, and then filtered through a 0.2 μm membrane filter to prepare a resist composition (wherein parts are based on weight).

For each of the obtained composition solutions, the resin was used in the same manner as in Example 11 except that ArF excimer laser exposure apparatus (lens numerical aperture 0.75) was used, and various evaluations were performed after forming a positive resist pattern.

[Formula 6]

Figure 1 shows the ¹ H-NMR results of the polymer represented by the formula (2a) of the present invention,

Figure 2 shows the ¹ H-NMR results of the polymer represented by the general formula (2e) of the present invention,

Figure 3 shows the ¹ H-NMR results of the polymer represented by the general formula (2b) of the present invention,

Figure 4 shows the ¹ H-NMR results of the polymer represented by the formula (2c) of the present invention,

Figure 5 shows the ¹ H-NMR results of the polymer represented by the general formula (2f) of the present invention,

Figure 6 shows the ¹ H-NMR results of the polymer represented by the general formula (2g) of the present invention,

Figure 7 shows the ¹ H-NMR results of the polymer represented by the formula (2h) of the present invention,

Figure 8 shows the ¹ H-NMR results of the polymer represented by the general formula (2i) of the present invention,

Figure 9 shows the ¹ H-NMR results of the polymer represented by the general formula (2k) of the present invention,

Figure 10 shows the ¹ H-NMR results of the polymer represented by the general formula (2l) of the present invention,

11 shows the results of gel permeation chromatography (GPC) of the polymer represented by the formula (2a) of the present invention,

12 shows the results of GPC of the polymer represented by the formula (2e) of the present invention,

Figure 13 shows the GPC results of the polymer represented by the general formula (2b) of the present invention,

14 shows the GPC results of the polymer represented by Chemical Formula 2c of the present invention,

15 shows the GPC results of the polymer represented by Chemical Formula 2f of the present invention,

Figure 16 shows the GPC results of the polymer represented by the formula 2g of the present invention,

Figure 17 shows the GPC results of the polymer represented by the formula (2h) of the present invention,

18 shows the GPC results of the polymer represented by Chemical Formula 2i of the present invention.

19 shows GPC results of a polymer represented by Chemical Formula 2k of the present invention,

20 shows the GPC results of the polymer represented by Chemical Formula 2l of the present invention.

Figure 21 shows the glass transition temperature (Tg) results of the polymer represented by the formula (2a) of the present invention,

22 shows the glass transition temperature (Tg) result of the polymer represented by Chemical Formula 2e of the present invention.

Figure 23 shows the glass transition temperature (Tg) results of the polymer represented by the general formula (2b) of the present invention,

24 shows the glass transition temperature (Tg) result of the polymer represented by Chemical Formula 2c of the present invention.

25 shows the glass transition temperature (Tg) result of the polymer represented by Chemical Formula 2f of the present invention.

Figure 26 shows the glass transition temperature (Tg) results of the polymer represented by the general formula (2g) of the present invention,

27 shows the glass transition temperature (Tg) result of the polymer represented by Chemical Formula 2h of the present invention.

28 shows the glass transition temperature (Tg) result of the polymer represented by Chemical Formula 2i of the present invention.

29 shows the glass transition temperature (Tg) result of the polymer represented by Chemical Formula 2k of the present invention.

30 shows the glass transition temperature (Tg) result of the polymer represented by Chemical Formula 2l of the present invention.

Claims (12)

A copolymer for chemically amplified photoresist represented by the following formula (1). Formula 1

Wherein R _1, R _2, R _3, R _4, R _5, R _6, and R ₇ is R _1, written to be independent of each other, R _2, R ₃ is a hydrogen atom, an ether group, an ester group, a carbonyl group, Carbon atoms with or without an acetal group, an epoxy group, a nitrile group, or an aldehyde group represent from 1 to 30 alkyl groups. R <_5>, R <_6> , R <_7> is respectively independently hydrogen or a methyl group, and R <_4> is an acetyl group or a trihalo acetyl group. l, m, n, o are the numbers of repeating units in the main chain, respectively, l + m + n + o = 1, 0.1≤l / (l + m + n + o) ≤0.5, 0.1≤m / (l + m + n + o) ≦ 0.7, 0.1 ≦ n / (l + m + n + o) ≦ 0.7, and 0 <o / (l + m + n + o) ≦ 0.5. The copolymer of claim 1, wherein the copolymer is selected from the group represented by the following Chemical Formulas 2a to 2l. In Formulas 2a to 2l, l, m, n, o are as defined in Formula 1.

The method according to claim 1 or 2, The repeating unit represented by l is a copolymer for chemically amplified photoresist, characterized in that it comprises 20 mol% to 40 mol% of the total monomers. The method according to claim 1 or 2, The repeating unit represented by o is a copolymer for chemically amplified photoresist, characterized in that contained in 10 mol% to 40 mol% of the total monomers. The copolymer for chemically amplified photoresist according to claim 1 or 2, wherein the weight average molecular weight is 2,000 to 1,000,000. The copolymer for chemically amplified photoresist according to claim 1 or 2, wherein the weight average molecular weight is 3,000 to 50,000. A chemically amplified photoresist composition comprising at least one polymer, an acid generator, an additive, and a solvent selected from copolymers represented by the following Chemical Formula 1. Formula 1

Wherein R _1, R _2, R _3, R _4, R _5, R _6, and R ₇ is R _1, written to be independent of each other, R _2, R ₃ is a hydrogen atom, an ether group, an ester group, a carbonyl group, Carbon atoms with or without an acetal group, an epoxy group, a nitrile group, or an aldehyde group represent from 1 to 30 alkyl groups. R <_5>, R <_6> , R <_7> is respectively independently hydrogen or a methyl group, and R <_4> is an acetyl group or a trihalo acetyl group. l, m, n, o are the numbers of repeating units in the main chain, respectively, l + m + n + o = 1, 0.1 <l / (l + m + n + o) <0.5, 0.1≤m / (l + m + n + o) <0.7, 0.1 ≦ n / (l + m + n + o) <0.7, and 0 <o / (l + m + n + o) <0.5. The chemically amplified photoresist composition according to claim 7, wherein the acid generator is at least one compound selected from compounds represented by the following Chemical Formulas 3 and 4.

In Formulas 3 and 4, R ₁ and R ₂ each independently represent an alkyl group, an allyl group, a perfluoroalkyl group, a benzyl group, or an aryl group, and R ₃ , R _4, and R ₅ represent hydrogen, an alkyl group, or a halogen group. , Alkoxy group, aryl group, thiophenoxy, thioalkoxy, or alkoxycarbonylmethoxy group, A of the anion moiety is OSO ₂ CF ₃ , OSO ₂ C ₄ F _{9 ,} OSO ₂ C ₈ F _{17 ,} N (CF ₃ ) _2, N (C ₂ F ₅ ) _2, N (C ₄ F ₉ ) _2, C (CF ₃ ) _3, C (C ₂ F ₅ ) _3, C (C ₄ F ₉ ) _3, It is selected from the compound represented by the formula (5a), (5b), (5c), (5d) or the compound represented by the formula (5e).

The chemically amplified photoresist composition according to claim 7, wherein the acid generator is included in an amount of 0.3 to 10 parts by weight based on 100 parts by weight of the polymer solids content. 8. The chemically amplified photoresist composition according to claim 7, wherein 3 wt% to 20 wt% of one or more polymers selected from the copolymers represented by Chemical Formula 1 is included. Forming a photoresist film by applying the chemically amplified photoresist composition of claim 7 to a substrate; Exposing the photoresist film in a predetermined pattern; And A method of forming a photoresist pattern comprising developing the exposed photoresist pattern. 12. The method of claim 11, wherein the exposure source of the exposing step is one selected from a KrF excimer laser, an ArF excimer laser, an X-ray, and an e-beam.

Images