KR20100073588A - Photosensitive polymer and photoresist composition including the same - Google Patents

Abstract

PURPOSE: A photosensitive polymer and a photoresist composite including thereof are provided to control the solubility of the photosensitive polymer to a developer and the contact angle of a photoresist, and to improve the resolution of a lithography process. CONSTITUTION: A photosensitive polymer is marked with chemical formula 1. In the chemical formula 1, R1, R2 and R3 are hydrogen or methyl groups. R4 is a linear, branched, monocyclic, or multicyclic alkyl group of C1~C40. R5 is a linear, branched, monocyclic, or multicyclic alkyl group including an ether group or an ester group. N is an integer selected from 1~15. X is a linear or branched alkyl group of C5~C120 containing heteroatom.

Description

Photosensitive polymer and photoresist composition including the same {Photosensitive polymer and photoresist composition including the same}

The present invention relates to a photosensitive polymer and a photoresist composition comprising the same, and more particularly, by preparing a photosensitive polymer by a reversible addition fragmentation chain transfer (RAFT) polymerization method using a chain transfer agent including hydrophilic and lipophilic functional groups. The present invention relates to a photosensitive polymer capable of adjusting the molecular weight and solubility of a photosensitive polymer and a contact angle of a photoresist, and a photoresist composition comprising the same.

In order to manufacture a semiconductor chip or a display element by processing a semiconductor wafer or display glass, a circuit structure of a predetermined pattern must be formed by using a photolithography process. The photosensitive material used in the photolithography process is called a photoresist composition. Recently, as the circuit pattern of a semiconductor or a display device is miniaturized, the need for a photoresist composition having a high resolution is increasing.

Conventional photoresist compositions include photosensitive polymers, photoacid generators (PAGs), organic solvents and, if necessary, basic compounds. When the main photosensitive polymer has a narrow polydispersity, the molecular weight of the photosensitive polymer is increased. It is easy to control and can reduce the nonuniformity of the photosensitive polymer can have a high resolution. In addition, if the solubility of the developer and the contact angle of the photoresist with respect to the immersion liquor existing in the immersion lithography equipment can be controlled, defects in water marks and bridges appearing in the immersion lithography process ) Defects can be solved.

Accordingly, an object of the present invention is to provide a photoresist polymer and a photoresist composition including the same, which can control the molecular weight of the photosensitive polymer, the solubility in the developer and the contact angle of the photoresist.

Another object of the present invention is to provide a photosensitive polymer and a photoresist composition including the same, which can improve resolution of a lithography process and improve line edge roughness (LER).

In order to achieve the above object, the present invention provides a photosensitive polymer having a structure of the formula (1).

[Formula 1]

In Formula 1, R ₁ , R ₂ and R ₃ are hydrogen or methyl, R ₄ is a C1 to C40 linear, branched, monocyclic or polycyclic alkyl group, R ₅ is substituted with a hydroxy group or a hydroxy group and a halogen group Or a C1 to C40 linear, branched, monocyclic or polycyclic alkyl group comprising an ether group or an ester group, and R ₆ is a C1 to C40 linear, branched, monocyclic or polycyclic group containing a lactone group Is an alkyl group, n is an integer of 1 to 15, X is a C5 to C120 linear or branched alkyl group containing heterogeneous elements, a, b and c are each repeating unit for all monomers constituting the photosensitive polymer As mole% of a, b and c are 1 to 99 mole%, 1 to 99 mole% and 0 to 98 mole%, respectively.

Here, the photosensitive polymer is characterized in that it is prepared by a reversible addition fragmentation chain transfer (RAFT) polymerization method using a chain transfer agent represented by the following formula (2).

[Formula 2]

In Formula 2, n is an integer of 1 to 15, X is a linear or branched alkyl group of C5 to C120 containing heterogeneous elements.

In addition, the present invention is 1 to 85% by weight of the photosensitive polymer having a structure of Formula 1 relative to the entire photoresist composition; 0.1 to 10% by weight of a photoacid generator for generating an acid, based on the total photoresist composition; And it provides a photoresist composition comprising the remaining organic solvent.

The photosensitive polymer according to the present invention and the photoresist composition comprising the same have a narrow polydispersity by preparing the photosensitive polymer by a reversible addition fragmentation chain transfer (RAFT) polymerization method using a chain transfer agent including hydrophilic and lipophilic functional groups. It is possible to easily control the molecular weight of the photosensitive polymer, thereby reducing the nonuniformity of the photosensitive polymer, and even when patterning using a mask having a resolution of 65 nm, high resolution of 45 nm or less is exhibited. In addition, since the photosensitive polymer may include various hydrophilic and lipophilic functional groups according to the chain transfer agent, the solubility of the photoresist composition in the developer can be controlled, and the photoresist for the immersion lithography in the immersion lithography process can be controlled. By adjusting the contact angle so that the immersion liquid does not remain in the photosensitive film after exposure, there is an advantage that can control the defects (watermarks), bridge defects (water mark). The photoresist composition of the present invention is also useful for nanoscale patterning such as extreme ultraviolet lithography (EUVL), immersion lithography process, etc. to form an ultrafine pattern by the above characteristics.

Hereinafter, the present invention will be described in detail.

The photosensitive polymer according to the present invention has a structure including hydrophilic and lipophilic functional groups, and is represented by the following Chemical Formula 1.

(여기서, 굴곡선은 접합부위)이고, R₅는 히드록시기 또는 히드록시기 및 할로겐기로 치환되거나, 에테르기 또는 에스테르기를 포함하는, C1 내지 C40의 선형, 분지형, 단일환형 또는 다환형의 알킬기, 바람직하게는, 히드록시기로 치환된 C1 내지 C30의 알킬기, 더욱 바람직하게는

(여기서, 굴곡선은 접합부위)이고, 이고, R₆는 락톤기를 포함하는, C1 내지 C40, 바람직하게는 C1 내지 C30의 선형, 분지형, 단일환형 또는 다환형의 알킬기, 더욱 바람직하게는

(여기서, 굴곡선은 접합부위)이며, n은 1 내지 15, 바람직하게는 2 내지 10의 정수이고, X는 이종 원소를 포함하는 C5 내지 C120의 선형 또는 분지형의 알킬기, 바람직하게는 산소원자(O)를 포함하는 C5 내지 C120의 선형 또는 분지형의 알킬기, 더욱 바람직하게는

,

,

및

(여기서, m은 1 내지 40, 바람직하게는 1 내지 30의 정수이고, 굴곡선은 결합부위를 나타낸다)이다. a, b 및 c는 상기 감광성 고분자를 이루는 전체 단량체에 대한 각 반복 단위의 몰%로서, a, b 및 c는 각각 1 ~ 99몰%, 1 ~ 99몰% 및 0 ~ 98몰%, 바람직하게는 5 ~ 90몰%, 5 ~ 90 몰% 및 5 ~ 90몰%이다.In Formula 1, R ₁ , R ₂ and R ₃ are hydrogen or a methyl group, R ₄ is C1 to C40 (ie, 1 to 40 carbon atoms), preferably C1 to C30 linear, branched, monocyclic or multi Cyclic alkyl groups, more preferably

(Where the bend is a junction) and R ₅ is a C1 to C40 linear, branched, monocyclic or polycyclic alkyl group, preferably substituted with a hydroxy group or a hydroxy group and a halogen group, or comprising an ether group or an ester group. Is an alkyl group of C1 to C30 substituted with a hydroxy group, more preferably

(Where the bend is a junction), and R ₆ is a C1 to C40, preferably C1 to C30, linear, branched, monocyclic or polycyclic alkyl group comprising a lactone group, more preferably

(Where the bend is a junction), n is an integer of 1 to 15, preferably 2 to 10, and X is a C5 to C120 linear or branched alkyl group containing heterogeneous elements, preferably an oxygen atom C5 to C120 linear or branched alkyl group comprising (O), more preferably

,

,

And

(Wherein m is an integer of 1 to 40, preferably 1 to 30, and a curved line represents a bonding site). a, b and c are mole% of each repeating unit with respect to the entire monomer constituting the photosensitive polymer, a, b and c are 1 to 99 mol%, 1 to 99 mol% and 0 to 98 mol%, preferably Is 5 to 90 mol%, 5 to 90 mol% and 5 to 90 mol%.

Representative examples of the photosensitive polymer represented by Chemical Formula 1 may include the following Chemical Formulas 1a to 1d,

In Formulas 1a to 1d, a, b, c and n are as defined in Formula 1, m is an integer of 1 to 40, preferably 1 to 30.

The photosensitive polymer according to the present invention may be a block copolymer or a random copolymer, and the weight average molecular weight (Mw) of the photosensitive polymer is 3,000 to 20,000, preferably 5,000 to 15,000, and polydispersity is 1.0 to 5.0, preferably 1.05 to 2.55. 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 dropwise polymerization method which is usually used as a method for producing a photosensitive polymer (base resin for resist material) is difficult to be dissolved in a resist solvent at the beginning of polymerization because the polymer composition tends to be unbalanced at the beginning of polymerization and tends to have a high molecular weight. A trace amount of poorly soluble component is generated, and the poorly soluble component is patterned in a photolithography process, and water droplets appear in a poorly soluble defect and an immersion lithography process. It may also be a cause of fatal defects such as defects and bridge defects. In view of the fact that the solubility of the photosensitive polymer in the solvent depends on the molecular weight, it is effective to reduce the molecular weight of the photosensitive polymer produced at the beginning of polymerization in order to reduce the poorly soluble component. As a method of reducing the molecular weight of the photosensitive polymer produced at the beginning of the polymerization, it is also conceivable to introduce a radical polymerization initiator into the polymerization vessel in advance. However, in such a method, the difference in the thermal history between the input of the initiator and the supply of the monomers can be considered. Since the amount of the initiator remaining in the polymerization vessel is changed, the molecular weight and dispersion degree of the photosensitive polymer obtained are changed for each lot.

RAFT (reversible addition fragmentation chain transfer) polymerization is a type of living free radical polymerization (LFRP) method, by controlling the reactivity of the radicals of the polymer chain formed by the initiator by using a chain transfer agent, It is to synthesize a polymer having molecular weight and distribution.

In the present invention, a photosensitive polymer is prepared by the RAFT polymerization method using a chain transfer agent represented by the following formula (2) as the chain transfer agent.

In Formula 2, n and X are as defined in Formula 1.

The RAFT polymerization method is a polymerization method that can control the reactivity of the radical using a chain transfer agent. Specifically, in the case of a polymerization method using a general radical polymerization initiator, a repeating unit having a polar group is generated at the initial stage of polymerization, and thus the reaction conditions tend to increase the molecular weight of the polymer, and thus a component having low solubility in a resist solvent may be generated. Big. However, if a solution containing a polymer and a polymerization initiator is kept at an appropriate temperature (approximately 30 ° C to 40 ° C), a chain transfer agent (chain transfer agent) is applied and the temperature is increased by the polymerization temperature (60 ° C to 100 ° C). The radical of the initiator is converted into a chain transfer agent (chain transfer agent) so that the molecular weight is dependent on the concentration of the chain transfer agent during the production of the polymer, so that it is possible to suppress fluctuations in the molecular weight and the degree of dispersion of the polymer. Accordingly, the photoresist composition including the photosensitive polymer may have poor solubility defects in the photolithography process, watermark defects, bridge defects, etc. It becomes small and becomes very useful for formation of a fine pattern.

The chain transfer agent represented by Chemical Formula 2 used in the RAFT polymerization method may be represented by the following Scheme 1 (where X is defined in Chemical Formula 1) and Scheme 2 (where n and X are defined in Chemical Formula 1). As shown in), the ethoxy propanol derivative (X-OH) and toluenesulfonyl chloride (TsCl) were reacted under a base catalyst to obtain chain transfer intermediates (X-OTs) (Scheme 1). X-OTs) and a substance represented by Chemical Formula 3 of Scheme 2 can be obtained by reacting with a base catalyst (Scheme 2).

,

,

)를 사용하여 RAFT 중합방법으로 제조할 수 있으며, 이때 개시제로는 당업계에서 통상적으로 알려진 중합개시제를 광범위하게 사용할 수 있으며, 비한정적으로는 아조비스이소부티로니트릴(AIBN) 등을 예시할 수 있다.The photosensitive polymer according to the present invention is represented by the following Scheme 3 (where a, b, c, n, X, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and R ₆ are as defined in Formula 1) As shown in the above, the chain transfer agent represented by the formula (2) and the monomer of Scheme 3 (

,

,

) May be prepared by the RAFT polymerization method, and as the initiator, a polymerization initiator commonly known in the art may be widely used, and without limitation, azobisisobutyronitrile (AIBN) may be exemplified. have.

The photoresist composition according to the present invention includes a photosensitive polymer represented by Chemical Formula 1, a photoacid generator, and an organic solvent, and may further include an organic base as a basic stabilizer if necessary. In the photoresist composition, the content of the photosensitive polymer is 1 to 85% by weight, preferably 5 to 60% by weight, and the content of the photoacid generator is 0.1 to 10% by weight, preferably 0.2 to 5% by weight. And the remaining components of the photoresist composition are organic solvents. In addition, when a basic stabilizer is used, the usage-amount is 0.01 to 5 weight%, Preferably it is 0.02 to 2 weight% in the said photoresist composition. Here, when the content of the photosensitive polymer is less than 1% by weight, it is difficult to form a photosensitive film having a desired thickness. When it exceeds 85% by weight, the thickness distribution of the pattern formed on the substrate may be uneven. In addition, when the content of the photoacid generator is less than 0.1% by weight, the sensitivity to light of the photoresist is lowered, and when the content of the photoresist exceeds 10% by weight, the photoacid generator absorbs much of ultraviolet rays, and an excess of acid is generated to form a pattern. There is a possibility that the cross-sectional shape of the surface becomes nonuniform. In addition, when the basic compound is used, if the content is less than 0.01% by weight, it is not easy to control the diffusion of acid generated during exposure, so that the cross-sectional shape of the pattern may be uneven. There is a possibility that the excessively suppressed and the formation of the pattern is difficult.

As the photoacid generator, a compound which generates an acid by irradiation of light can be used without limitation, and an onium salt commonly used as a photoacid generator of a photoresist composition, for example, a sulfonium salt or iodo You may use a nium salt compound. Especially with phthalimidotrifluoromethane sulfonate, dinitrobenzyl tosylate, n-decyl disulfone, and naphthylimido trifluoromethane sulfonate Diphenyl iodide triflate, diphenyl iodo salt nonaplate, diphenyl iodo salt hexafluorophosphate, diphenyl iodo salt hexafluoroarsenate, diphenyl iodo salt hexafluoroantimo Nitrate, diphenylparamethoxyphenylsulfonium triflate, diphenylparatoluenylsulfonium triflate, diphenyl parateruylbutylphenylsulfonium triflate, diphenylparaisobutyl phenylsulfonium triflate, triphenylsulfonium Triflate, Trisparaterrarybutylphenylsulfonium Triflate, Diphenylpara Methoxyphenylsulfonium nona plate, diphenyl paratoluenyl sulfonium nona plate, diphenyl para tertiary butylphenyl sulfonium nona plate, diphenyl paraisobutyl phenyl sulfonium nona plate, triphenyl sulfonium nona plate, tri Photoacid generators selected from the group consisting of spatterary butylphenylsulfonium nonaplate, hexafluoro arsenate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium triflate and dibutylnaphthylsulfonium triflate Can be used.

As the organic solvent, an organic solvent commonly used as a solvent of the photoresist composition can be used without limitation, and for example, ethylene glycol monomethyl ethyl, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol mono Acetate, diethylene glycol, diethylene glycol monoethyl ether, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol, propylene glycol monoacetate, toluene, xylene, methyl ethyl ketone, methyl isoamyl ketone, cyclohexanone, Dioxane, methyl lactate, ethyl lactate, methylpyruvate, ethyl pyruvate, methylmethoxypropionate, ethylethoxypropionate, N, N-dimethylformamide, N, N-dimethylacetamide, N -Methyl2-pyrrolidone, 3-ethoxyethylpropionate, 2-heptanone, gamma-butyrolactone, 2-hydroxypropionethyl, 2- Ethyl hydroxy 2-methyl propionate, ethyl ethoxy acetate, ethyl hydroxy acetate, 2-hydroxy 3-methyl butyrate, 3-methoxy 2-methyl methyl propionate, 3-ethoxy propionate, 3-methoxy Ethyl 2-methylpropionate, ethyl acetate, butyl acetate, mixtures thereof and the like can be used.

In addition, as the organic base used as the basic stabilizer (quencher), organic bases commonly used may be used without limitation, for example, triethylamine, trioctylamine, triisobutylamine, triisooctylamine And organic bases such as diethanolamine, triethanolamine, and mixtures thereof.

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

Preparation Example 1-1 Synthesis of Intermediate Chain Transfer Agents Represented by Chemical Formula 4a

, m은 8) 30.0g, 톨루엔설포닐클로라이드(TsCl, Ts=

, 굴곡선은 접합부위) 32.6g을 메틸렌클로라이드 100.0g에 용해시킨 후, 실온에서 피리딘(6.27ml, 77.6mmol)을 첨가하고, 12시간 동안 반응시켰다. 반응 종료 후, 반응액을 물로 세척하고, 메틸렌클로라이드로 추출하여 분리한 다음, 무수 마그네슘 설페이트를 첨가하고 여과시켰다. 그 여액을 감압증류기에 넣고, 메틸렌클로라이드를 증발시킨 후, 실리카겔을 이용한 컬럼크로마토그래피를 통해서 생성물을 분리하여, 무색의 액체 화합물인 화학식 4a로 표시되는 사슬이동제 중간 체 21.4g을 얻었다{수율: 68.3%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 7.82(CH, 2H), 7.40(CH, 2H), 3.54(CH₂, 64H), 3.49(CH₂, 2H), 3.33(CH₂, 4H) 3.24(CH₃, 6H), 2.35(CH₃, 18H)}.As shown in Scheme 1, under nitrogen, an ethoxy propanol derivative (X-OH, X =

, m is 8) 30.0 g, toluenesulfonylchloride (TsCl, Ts =

After dissolving 32.6 g of methylene chloride in 100.0 g of a curved line, pyridine (6.27 ml, 77.6 mmol) was added at room temperature and reacted for 12 hours. After the reaction was completed, the reaction solution was washed with water, extracted with methylene chloride, separated, anhydrous magnesium sulfate was added and filtered. The filtrate was placed in a distillation under reduced pressure, the methylene chloride was evaporated, and the product was separated through column chromatography using silica gel to obtain 21.4 g of a chain transfer intermediate represented by the formula (4a) as a colorless liquid compound (yield: 68.3 %, 1 H-NMR (CDCl ₃ , internal standard): δ (ppm) 7.82 (CH, 2H), 7.40 (CH, 2H), 3.54 (CH ₂ , 64H), 3.49 (CH ₂ , 2H), 3.33 ( CH ₂ , 4H) 3.24 (CH ₃ , 6H), 2.35 (CH ₃ , 18H)}.

Preparation Example 1-2 Synthesis of Intermediate Chain Transfer Agent of Formula 4b

, m은 8) 대신 X-OH(X=

, m은 8)를 사용한 것을 제외하고는, 상기 제조예 1-1과 동일한 방법으로, 무색의 액체 화합물인 화학식 4b로 표시되는 사슬이동제 중간체 20.1g을 얻었다{수율: 65.2%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 7.82(CH, 2H), 7.40(CH, 2H), 3.50(CH₂, 32H), 3.49(CH₂, 2H), 3.34(CH, 16H), 3.33(CH₂, 4H), 3.24(CH₃, 6H), 2.35(CH₃, 3H), 2.28(CH, 1H), 1.21(CH₃, 48H)}.Ethoxy propanol derivatives were converted to X-OH (X =

, m is 8) instead of X-OH (X =

, m was obtained in the same manner as in Preparation Example 1-1, except that 8), 20.1 g of a chain transfer intermediate represented by the general formula (4b) as a colorless liquid compound (yield: 65.2%, 1H-NMR ( CDCl ₃ , internal standard): δ (ppm) 7.82 (CH, 2H), 7.40 (CH, 2H), 3.50 (CH ₂ , 32H), 3.49 (CH ₂ , 2H), 3.34 (CH, 16H), 3.33 (CH ₂ , 4H), 3.24 (CH ₃ , 6H), 2.35 (CH ₃ , 3H), 2.28 (CH, 1H), 1.21 (CH ₃ , 48H)}.

Preparation Example 1-3 Synthesis of Intermediate Chain Transfer Agent of Formula 4c

, m은 8) 대신 X-OH(X=

, m은 1)를 사용한 것을 제외하고는, 상기 제조예 1-1과 동일한 방법으로, 무색의 액체 화합물인 화학식 4c로 표시되는 사슬이동제 중간체 18.3g을 얻었다{수율: 57.8%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 7.82(CH, 2H), 7.40(CH, 2H), 3.54(CH₂, 16H), 3.49(CH₂, 2H), 3.33(CH₂, 16H), 3.24(CH₃, 12H), 2.46(CH, 2H), 2.35(CH₃, 3H), 2.28(CH, 1H)}.Ethoxy propanol derivatives were converted to X-OH (X =

, m is 8) instead of X-OH (X =

, m was obtained in the same manner as in Preparation Example 1-1, except that 1), 18.3 g of a chain transfer intermediate represented by Chemical Formula 4c as a colorless liquid compound was obtained (yield: 57.8%, 1H-NMR ( CDCl ₃ , internal standard): δ (ppm) 7.82 (CH, 2H), 7.40 (CH, 2H), 3.54 (CH ₂ , 16H), 3.49 (CH ₂ , 2H), 3.33 (CH ₂ , 16H), 3.24 (CH ₃ , 12H), 2.46 (CH, 2H), 2.35 (CH ₃ , 3H), 2.28 (CH, 1H)}.

Preparation Example 1-4 Synthesis of Intermediate Chain Transfer Agent Represented by Chemical Formula 4d

, m은 8) 대신 X-OH(X=

)를 사용한 것을 제외하고는, 상기 제조예 1-1과 동일한 방법으로, 무색의 액체 화합물인 화학식 4d로 표시되는 사슬이동제 중간체 17.4g을 얻었다{수율: 53.9%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 7.82(CH, 2H), 7.40(CH, 2H), 3.49(CH₂, 2H), 3.41(CH₂, 12H), 3.33(CH₂, 4H), 3.29(CH₂, 12H), 2.35(CH₃, 3H), 2.28(CH, 1H), 2.35(CH₃, 18H)}.Ethoxy propanol derivatives were converted to X-OH (X =

, m is 8) instead of X-OH (X =

) Was obtained in the same manner as in Preparation Example 1-1, to obtain 17.4 g of a chain transfer intermediate represented by Chemical Formula 4d as a colorless liquid compound (yield: 53.9%, 1H-NMR (CDCl ₃ , internal Standard): δ (ppm) 7.82 (CH, 2H), 7.40 (CH, 2H), 3.49 (CH ₂ , 2H), 3.41 (CH ₂ , 12H), 3.33 (CH ₂ , 4H), 3.29 (CH ₂ , 12H), 2.35 (CH ₃ , 3H), 2.28 (CH, 1H), 2.35 (CH ₃ , 18H)}.

Preparation Example 2-1 Synthesis of Chain Transfer Agent Represented by Chemical Formula 2a

, m은 8) 20.0g과 2-머캅토에탄올(2-Mercaptoethanol, 화학식 3, n은 1) 15.3g을 에탄올(EtOH)에 용해시킨 후, 포타슘카보네이트(K₂CO₃)를 첨가하고, 24시간 동안 80℃에서 환류시켰다. 반응 종료 후, 과량의 포타슘하이드록사이드(KOH)를 첨가하고, 3시간 동안 실온에서 교반하였으며, 반응액을 물로 세척하고, 메틸렌클로라이드로 추출하고 분리한 다음, 무수 마그네슘 설페이트를 첨가하고 여과시켰다. 그 여액을 감압증류기에 넣고, 메틸렌클로라이드를 증발시킨 후, 실리카겔을 이용한 컬럼크로마토그래피를 통해서 생성물을 분리하여, 화학식 2a로 표시되는 사슬이동제 12.2g을 얻었다{수율: 65.3%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 3.67(CH₂, 2H), 3.54(CH₂, 64H), 3.33(CH₂, 6H), 3.24(CH₃, 6H), 2.73(CH₂, 2H), 2.46(CH, 1H), 1.50(SH, 1H)}.As shown in Scheme 2, the chain transfer agent represented by Chemical Formula 4a (X-OTs, X =

, m is 8) 20.0 g and 2-mercaptoethanol (2-Mercaptoethanol (Formula 3, n is 1) 1) dissolved in ethanol (EtOH), then potassium carbonate (K ₂ CO ₃ ) is added, 24 Reflux at 80 ° C. for hours. After completion of the reaction, excess potassium hydroxide (KOH) was added and stirred at room temperature for 3 hours, the reaction solution was washed with water, extracted with methylene chloride and separated, anhydrous magnesium sulfate was added and filtered. The filtrate was put in a vacuum distillation, methylene chloride was evaporated and the product was separated by column chromatography using silica gel to obtain 12.2 g of a chain transfer agent represented by Chemical Formula 2a (yield: 65.3%, 1H-NMR (CDCl). ₃ , internal standard): δ (ppm) 3.67 (CH ₂ , 2H), 3.54 (CH ₂ , 64H), 3.33 (CH ₂ , 6H), 3.24 (CH ₃ , 6H), 2.73 (CH ₂ , 2H) , 2.46 (CH, 1 H), 1.50 (SH, 1 H)}.

Preparation Example 2-2 Synthesis of Chain Transfer Agent Represented by Chemical Formula 2b

, m은 8) 대신 X-OTs(X=

, m은 8)를 사용한 것을 제외하고는, 상기 제조예 2-1과 동일한 방법으로, 화학식 2b로 표시되는 사슬이동제 13.4g을 얻었다{수율: 70.1%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 3.67(CH₂, 2H), 3.50(CH₂, 32H), 3.34(CH, 16H), 3.33(CH₂, 6H), 3.24(CH₃, 6H), 2.73(CH₂, 2H), 2.46(CH, 1H), 1.50(SH, 1H), 1.21(CH₃, 48H)}.Chain transfer intermediates are described as X-OTs (X =

, m is 8) instead of X-OTs (X =

, m was obtained in the same manner as in Preparation Example 2-1, except that 8), 13.4g of a chain transfer agent represented by the formula (2b) {yield: 70.1%, 1H-NMR (CDCl ₃ , internal standard) ): δ (ppm) 3.67 (CH ₂ , 2H), 3.50 (CH ₂ , 32H), 3.34 (CH, 16H), 3.33 (CH ₂ , 6H), 3.24 (CH ₃ , 6H), 2.73 (CH ₂ , 2H), 2.46 (CH, 1H), 1.50 (SH, 1H), 1.21 (CH ₃ , 48H)}.

Preparation Example 2-3 Synthesis of Chain Transfer Agent Represented by Chemical Formula 2c

, m은 8) 대신 X-OTs(X=

, m은 1)를 사용한 것을 제외하고는, 상기 제조예 2-1과 동일한 방법으로, 화학식 2c로 표시되는 사슬이동제 12.6g을 얻었다{수율: 68.2%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 3.67(CH₂, 2H), 3.54(CH₂, 8H), 3.33(CH₂, 18H), 3.24(CH₃, 12H), 2.73(CH₂, 2H), 2.46(CH, 3H), 1.50(SH, 1H)}.Chain transfer intermediates are described as X-OTs (X =

, m is 8) instead of X-OTs (X =

, m was obtained in the same manner as in Preparation Example 2-1, except that 12.6g of the chain transfer agent represented by the formula (2c) {yield: 68.2%, 1H-NMR (CDCl ₃ , internal standard) ): δ (ppm) 3.67 (CH ₂ , 2H), 3.54 (CH ₂ , 8H), 3.33 (CH ₂ , 18H), 3.24 (CH ₃ , 12H), 2.73 (CH ₂ , 2H), 2.46 (CH, 3H), 1.50 (SH, 1H)}.

Preparation Example 2-4 Synthesis of Chain Transfer Agent Represented by Chemical Formula 2d

, m은 8) 대신 X-OTs(X=

)를 사용한 것을 제외하고는, 상기 제조예 2-1과 동일한 방법으로, 화학식 2d로 표시되는 사슬이동제 15.8g을 얻었다{수율: 55.7%, 1H-NMR(CDCl₃, 내부표준물질): δ(ppm) 3.67(CH₂, 2H), 3.41(CH₂, 12H), 3.33(CH₂, 6H), 3.29(CH₂, 16H), 2.73(CH₂, 2H), 2.46(CH, 1H), 1.50(SH, 1H), 1.11(CH₃, 18H)}.Chain transfer intermediates are described as X-OTs (X =

, m is 8) instead of X-OTs (X =

), 15.8 g of a chain transfer agent represented by Chemical Formula 2d was obtained in the same manner as in Preparation Example 2-1, except that the yield was 55.7%, 1H-NMR (CDCl ₃ , internal standard): δ ( ppm) 3.67 (CH ₂ , 2H), 3.41 (CH ₂ , 12H), 3.33 (CH ₂ , 6H), 3.29 (CH ₂ , 16H), 2.73 (CH ₂ , 2H), 2.46 (CH, 1H), 1.50 (SH, 1 H), 1.11 (CH ₃ , 18 H)}.

Example 1-1 Synthesis of Photosensitive Polymer Represented by Chemical Formula 1a

, R₄=

, R₁= 메틸기, 굴곡선은 접합부위) 19.6g(0.108mmol), R₅를 포함하는 모노머(

, R₅=

, R₂= 메틸기, 굴곡선은 접 합부위) 15g(0.067mmol) 및 R₆를 포함하는 모노머(

, R₆=

, R₃= 메틸기, 굴곡선은 접합부위) 20.9g(0.094mmol)과 아조비스이소부티로니트릴(AIBN) 0.2g을 테트라히드로퓨란 60mL에 첨가하여 40℃에서 녹인 후, 상기 화학식 2a로 표시되는 사슬이동제 2.0g(0.0034mmol)을 적하하고 67℃에서 14시간 동안 반응시켰다.반응 종료 후 반응액을 감압 증류한 후, 메탄올에서 고분자를 침전시키고, 여과하여 상기 화학식 1a로 표시되는 감광성 고분자(a=40.15몰%, b=24.90몰%, c=34.95몰%, m=8, n=1)를 얻었다(수율: 64%, 분산도: 1.86, 분자량: 5895).Monomer containing R ₄ (

, R ₄ =

, R ₁ = methyl, bend at the junction) 19.6 g (0.108 mmol), monomer containing R ₅ (

, R ₅ =

, R ₂ = methyl group, the flexion line is the junction) 15 g (0.067 mmol) and a monomer comprising R ₆ (

, R ₆ =

, R ₃ = methyl group, the curved line is a junction site) 20.9g (0.094mmol) and 0.2g of azobisisobutyronitrile (AIBN) was added to 60mL of tetrahydrofuran and dissolved at 40 ° C, which is represented by Formula 2a. 2.0 g (0.0034 mmol) of a chain transfer agent was added dropwise and reacted at 67 ° C. for 14 hours. After completion of the reaction, the reaction solution was distilled under reduced pressure, and then the polymer was precipitated in methanol, filtered and the photosensitive polymer represented by Chemical Formula 1a (a). = 40.15 mol%, b = 24.90 mol%, c = 34.95 mol%, m = 8, n = 1) (yield: 64%, dispersion degree: 1.86, molecular weight: 5895).

Example 1-2 Synthesis of Photosensitive Polymer Represented by Chemical Formula 1b

In the same manner as in Example 1-1, except that 2.3g (0.0038mmol) of the chain transfer agent represented by Formula 2b was used instead of 2.0g (0.0034 mmol) of the chain transfer agent represented by Formula 2a. The photosensitive polymer represented by Formula 1b (a = 40.15 mol%, b = 24.90 mol%, c = 34.95 mol%, m = 8, n = 1) was obtained (yield: 62%, dispersion degree: 1.65, molecular weight: 5423).

Example 1-3 Synthesis of Photosensitive Polymer Represented by Chemical Formula 1c

In the same manner as in Example 1-1, except that 2.4g (0.0042mmol) of the chain transfer agent represented by Formula 2c was used instead of 2.0g (0.0034 mmol) of the chain transfer agent represented by Formula 2a. The photosensitive polymer represented by Chemical Formula 1c (a = 40.15 mol%, b = 24.90 mol%, c = 34.95 mol%, m = 1, n = 1) was obtained (yield: 59.3%, dispersion degree: 1.59, molecular weight: 5103).

Example 1-4 Synthesis of Photosensitive Polymer Represented by Chemical Formula 1d

In the same manner as in Example 1-1, except that the chain transfer agent 1.8g (0.0027mmol) represented by the formula (2d) instead of 2.0g (0.0034 mmol) of the chain transfer agent represented by the formula (2a), A photosensitive polymer represented by Chemical Formula 1d (a = 40.15 mol%, b = 24.90 mol%, c = 34.95 mol%, n = 1) was obtained (yield: 54%, dispersion degree: 1.66, molecular weight: 4986).

[Examples 2-1 to 2-4] Preparation of a photoresist composition containing the photosensitive polymer prepared in Examples 1-1 to 1-4

According to the configuration of Table 1, 0.08 g of each of the photosensitive polymers (Formula 1a to 1d) triphenylsulfonium triflate and 0.02 g of trioctylamine prepared in Examples 1-1 to 1-4 were propylene glycol monomethyl After stirring for 20 hours in 20 g ether acetate (PGMEA), and then filtered by 0.05㎛ filter to prepare a photoresist composition.

Photosensitive polymer Photoacid generator Basic stabilizers Organic solvent Example 2-1 Formula 1a Triphenylsulfonium Nona Plate Trioctylamine Propylene Glycol Monomethyl Ether Acetate Example 2-2 Formula 1b Example 2-3 Formula 1c Examples 2-4 Formula 1d

Example 3 Exposure Pattern Formation Using Photoresist Composition

Each photoresist composition prepared in Examples 2-1 to 2-4 was spin-coated to a thickness of 1500Å over the etched layer of the silicon wafer to form a photoresist thin film, and then in an oven or hotplate at 120 ° C. It was prebaked for 60 seconds and exposed to ArF ASML1200B equipment with a numerical aperture of 0.85. After exposure at 120 ° C. for 60 seconds, a bake (PEB) was performed, and the baked wafer was immersed in a 2.38 wt% tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds and developed to give L / of 65 nm resolution. After the S (line / space) pattern was formed, its performance was evaluated. The process margins, energy latitude margin and focus margin, minimum resolution, line edge roughness and receding contact angle, are measured and the results are shown in the table below. 2 and the electron micrographs of the photoresist patterns according to each photoresist composition (Examples 2-1 to 2-4) are shown in FIGS. 1 to 4.

Photoresist
Composition Energy lattice
De Margin (%) Focus Margin
(Μm) Minimum resolution
(nm) Pattern edge
Roughness (nm) Reverse contact angle
(°) Example 2-1 17.8 0.64 45 3.5 80 Example 2-2 16.3 0.60 40 3.1 85 Example 2-3 15.3 0.61 35 3.3 83 Examples 2-4 19.3 0.63 33 3.6 87

In Table 2, the energy lattice margin is a process margin according to an appropriate exposure amount, and is measured and quantified by measuring a change in the pattern size according to an exposure amount. The focus margin is a process margin, and the depth of exposure light irradiated onto the resist film is measured. will be. Energy lattice margin, focus margin, minimum resolution and pattern edge roughness were measured using Hitachi's CD Scanning Electron Microscope (CD-SEM) .The contact angle was tilted using a data angle physics contact angle meter (Model: SCA20). Receding contact angle is measured using.

When the resist composition according to the present invention is patterned by using a mask having a resolution of 65 nm (Examples 2-1 to 2-4), resolution of 45 nm or less can be obtained, and when using a conventional photoresist composition, Although the pattern edge roughness shows a value of 5 to 6 nm, when using the composition according to the present invention, it can be seen that the pattern edge roughness shows a value of 3.1 to 3.6 nm, thereby significantly improving the pattern edge roughness characteristics. In addition, since the backward contact angle is 80 to 87 °, it is possible to reduce water mark defects, bridge defects, etc., which appear in the liquid immersion process, and the energy latitude margin is 15.3 to 19.3%. It is relatively easy to change or adjust the exposure amount and the focus margin is 0.60 to 0.64 mu m, which is useful for actual semiconductor processes.

1 is an electron micrograph of a photoresist pattern (65 nm 1: 1 L / S) formed using the photoresist composition according to Example 2-1 of the present invention.

2 is an electron micrograph of a photoresist pattern (65 nm 1: 1 L / S) formed using the photoresist composition according to Example 2-2 of the present invention.

3 is an electron micrograph of a photoresist pattern (65 nm 1: 1 L / S) formed using the photoresist composition according to Example 2-3 of the present invention.

4 is an electron micrograph of a photoresist pattern (65 nm 1: 1 L / S) formed using the photoresist composition according to Example 2-4 of the present invention.

Claims (6)

The photosensitive polymer represented by the following formula (1). [Formula 1]

In Formula 1, R ₁ , R ₂ and R ₃ are hydrogen or methyl, R ₄ is a C1 to C40 linear, branched, monocyclic or polycyclic alkyl group, R ₅ is substituted with a hydroxy group or a hydroxy group and a halogen group Or a C1 to C40 linear, branched, monocyclic or polycyclic alkyl group comprising an ether group or an ester group, and R ₆ is a C1 to C40 linear, branched, monocyclic or polycyclic group containing a lactone group Is an alkyl group, n is an integer of 1 to 15, X is a C5 to C120 linear or branched alkyl group containing heterogeneous elements, a, b and c are each repeating unit for all monomers constituting the photosensitive polymer As mole% of a, b and c are 1 to 99 mole%, 1 to 99 mole% and 0 to 98 mole%, respectively. The method of claim 1, wherein X is

,

,

And

Wherein m is an integer of 1 to 40, and a curve indicates a bonding site. The photosensitive polymer according to claim 1, wherein the photosensitive polymer is any one compound selected from the group consisting of compounds represented by the following Chemical Formulas 1a to 1d. [Formula 1a]

[Chemical Formula 1b]

[Formula 1c]

≪ RTI ID = 0.0 &

In Formulas 1a to 1d, a, b, c, and n are as defined in Formula 1, and m is an integer of 1 to 40. The photosensitive polymer of claim 1, wherein the photosensitive polymer is prepared by a RAFT polymerization method using a chain transfer agent represented by the following Chemical Formula 2. [Formula 2]

In Formula 2, n and X are as defined in Formula 1. The photosensitive polymer of claim 1, wherein the photosensitive polymer has a molecular weight of 3,000 to 20,000 and a polydispersity of 1.0 to 5.0. 1 to 85% by weight of the photosensitive polymer having a structure of Formula 1 based on the total photoresist composition; 0.1 to 10% by weight of a photoacid generator for generating an acid, based on the total photoresist composition; And Photoresist composition comprising the remaining organic solvent. [Formula 1]

In Formula 1, R ₁ , R ₂ and R ₃ are hydrogen or methyl, R ₄ is a C1 to C40 linear, branched, monocyclic or polycyclic alkyl group, R ₅ is substituted with a hydroxy group or a hydroxy group and a halogen group Or a C1 to C40 linear, branched, monocyclic or polycyclic alkyl group comprising an ether group or an ester group, and R ₆ is a C1 to C40 linear, branched, monocyclic or polycyclic group containing a lactone group Is an alkyl group, n is an integer of 1 to 15, X is a C5 to C120 linear or branched alkyl group containing heterogeneous elements, a, b and c are each repeating unit for all monomers constituting the photosensitive polymer As mole% of a, b and c are 1 to 99 mole%, 1 to 99 mole% and 0 to 98 mole%, respectively.

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