KR100400293B1 - Photoresist Monomers, Polymers thereof, and Photoresist Compositions Using the Same - Google Patents

Abstract

The present invention relates to a photoresist monomer, a polymer thereof, and a photoresist composition using the same, having a property suitable for a photolithography process employing a light source in the far ultraviolet region, in particular an ArF (193 nm) light source. 10 polymers are disclosed.

<Formula 2>

<Formula 10>

Wherein R ₁ , R ₂ , R ₅ , m, a, b, c and d are as defined in the specification.

Description

Photoresist monomers, polymers thereof and photoresist compositions using the same

The present invention relates to a novel photoresist monomer, a polymer thereof, and a photoresist composition using the same, and more particularly, to a photoresist monomer having a property suitable for a photolithography process employing a light source in the far ultraviolet region, a polymer thereof, and a polymer thereof. It is about the used photoresist composition.

Photoresist compositions used in photolithographic processes using extreme wavelength light sources, such as E-beams, KrF, EUV, X-rays, in particular ArF light sources, have a low light absorption at a wavelength of 193 nm while providing excellent etch resistance and adhesion. It has to satisfy various conditions such as developing with 2.38wt% tetramethylammonium hydroxide (TMAH) aqueous solution.

To date, many research directions have focused on the search for resin at the same level as the novolak resin with high transparency at 193 nm. Accordingly, attempts have been made to improve etching resistance by introducing alicyclic units into the main chain, but it is very difficult to configure all of the main chains into aliphatic rings, and when using metal as a catalyst, all of the main chains are aliphatic. Although it may be configured as a cyclic unit, in this case, it is difficult to remove the metal component contained in the resin, and this method is also difficult to use because the metal component in the resin has a fatal adverse effect on the semiconductor device.

In an attempt to solve the above problems, the polymer resin for photoresists represented by the following formula (1) consisting of norbornylene, acrylate and maleic anhydride is Bell Labs ( Bell Lab.).

<Formula 1>

However, this photoresist polymer resin is a maleic hydride (part A) used to polymerize an alicyclic olefin group and does not absorb light having a wavelength of 193 nm, but polymerizes with norbornylene, an aliphatic cyclic unit. Although this is the only possible material, there is a problem in that it is very well dissolved in a 2.38wt% TMAH aqueous solution even in non-exposure, so that a top loss phenomenon of rounding the upper part of the pattern when the actual photoresist pattern is formed is generated. Therefore, the ratio of the y part containing t-butyl introduced to inhibit dissolution must be greatly increased. However, as the y part increases, the z part (carboxylate part), which increases the adhesion and sensitivity to the substrate, is relatively decreased, resulting in the photoresist falling off the wafer during the actual patterning. The disadvantage is that it becomes impossible to form. In addition, during post-exposure delay in which the heat treatment is not performed immediately after exposure, a T-top phenomenon occurs in which the lower part of the pattern becomes smaller than the upper part, thereby making it difficult to form the pattern itself. Since the ride reacts with the hydroxy group (-OH) which increases the stickiness, there is a possibility that the shelf life of the photoresist agent is affected.

Therefore, Bell Labs attempted to solve these shortcomings by adding alternating copolymers with cycloolefins and maleic hydrides, which are two-components, by adding cholesterol-based dissolution inhibitors. Since a large amount of about 30% of the resin having such a molecular structure is fundamentally inferior in reproducibility and increases in cost, there is a problem in that it is difficult to use as a photoresist resin.

In order to solve the above problems, the present invention provides novel monomers for photoresists and polymers thereof.

Another object of the present invention is to provide a photoresist composition comprising the polymer and a semiconductor device manufactured using the same.

1 shows a photograph of a photoresist fine pattern according to a twelfth embodiment of the present invention,

2 shows a photograph of a photoresist fine pattern according to a fifteenth embodiment of the present invention,

3 shows a photograph of a photoresist fine pattern according to a sixteenth embodiment of the present invention.

The present invention provides a compound of formula 2 as a monomer for photoresist to achieve the above object.

<Formula 2>

Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is 1 carbon atom Substituted or unsubstituted linear or branched alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of 10 to 10, m is an integer selected from 0 to 3.

In addition, the present invention provides a compound of formula (10) as a photoresist polymer.

<Formula 10>

Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is carbon 1 to 10 substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl, R ₅ is hydroxyethyl or hydroxypropyl, m is an integer selected from 0 to 3, a: b: c: d = 10-80 mol%: 10-80 mol%: 0-70 mol%: 10-80 mol%.

In order to achieve another object of the present invention, the present invention provides a photoresist composition comprising the polymer of Formula 10, a photoacid generator, and an organic solvent.

Synthesis of Monomer for Photoresist

The present inventors conducted numerous studies and experiments in order to solve the problems of the prior art described above, and synthesized the compound of formula 2 as a monomer for photoresist.

<Formula 2>

Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is 1 carbon atom Substituted or unsubstituted linear or branched alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of 10 to 10, m is an integer selected from 0 to 3.

At least one of R ₁ and R ₂ is an acid labile protecting group, which is photosensitive because it is detached by an acid generated by light at the time of exposure so that the exposed part can be dissolved by the developer during the development process. Serves as a substituent. The acid sensitive protecting groups R ₁ and R ₂ are preferably substituted or unsubstituted linear or branched alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms as described above, and specifically, 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 and 2-acetylment-1 -Work and the like.

The compound of Formula 2 is a bicyclo alkene derivative, the photoresist resin formed by the polymerization structure of the bicyclo alkene derivative has excellent etching resistance. In addition, in the case of including two light-sensitive carboxylate substituents, the difference in solubility between the exposed portion and the non-exposed portion is large, so that a pattern having excellent resolution may be obtained when using a photoresist resin including the same. In addition, when two photosensitive substituents are included, in order to increase the ratio of additional functional monomers, even if the ratio of the monomer of Formula 2 is lowered to some extent in the polymer, the sensitivity of the photosensitive and the resulting solubility between the exposed and non-exposed parts may be reduced. The impact is mitigated.

The compound of Formula 2 is prepared using bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid as starting material, specifically, bicyclo [2.2.2] oct-5-ene- Prepared by reacting 2,3-dicarboxylic acid with a compound capable of providing R ₁ and R ₂ , which are acid sensitive protecting groups.

First, the starting material, bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid, is reacted with cyclohexadiene and maleic anhydride in an organic solvent to give bicyclo [2.2.2] oct- Prepared by obtaining 5-ene-2,3-dicarboxylic anhydride followed by hydrolysis. In this case, maleic anhydride is preferably used in the same molar number or slightly excessive amount as cyclohexadiene.

The bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid thus prepared is reacted with a compound capable of providing an acid sensitive protecting group as described above, providing an acid sensitive protecting group. Preferred examples of the compound that may be used include tert-butanol, 3,4-dihydro-2H-pyran, dihydrofuran, ethylbityl ether and tert-butyl vinyl ether.

In this case, when only one of R ₁ and R ₂ is substituted, the compound capable of providing an acid-sensitive protecting group is added with the same mole number based on the number of moles of starting material, and when both R ₁ and R ₂ are substituted, starting material. Use twice or slightly more excess based on the moles of.

The reaction between the starting material and the compound providing an acid sensitive protecting group is preferably carried out under acid catalyst or under basic conditions, and the reaction solvent is an organic solvent such as toluene, tetrahydrofuran, ethyl ether, benzene, dichloromethane or chloroform Can be used.

Hereinafter, specific examples of a novel photoresist monomer and a method of manufacturing the same according to the present invention will be disclosed, but the present invention is not limited thereto.

Example 1 Synthesis of Bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic Acid

After dissolving 1 mole of cyclohexadiene in 500 ml of THF, the temperature is cooled to -30 ° C. In this case, in addition to THF, toluene, ethyl ether, benzene, dichloromethane or chloroform may be used as the organic solvent.

The temperature is kept at -30 ° C while gradually adding the same molar ratio of maleic anhydride to the resultant cyclohexadiene. After reacting for about 10 hours, the temperature is gradually increased to room temperature and allowed to react for 10 hours. After completion of the reaction, the organic solvent was removed by rotary distillation, and then bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic anhydride was obtained by vacuum distillation (yield 92%).

Subsequently, 0.5 mole of the bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic anhydride synthesized above was added to a 10 wt% NaOH aqueous solution and dissolved well with slow stirring. Then, the temperature was raised to 85 ° C. and refluxed for 1.5 hours, and then the temperature was slowly lowered to room temperature. 10% sulfuric acid aqueous solution was slowly added dropwise to the reaction solution to adjust the pH to neutral, and the organic layer was separated with ethyl acetate using a separatory funnel. The combined solution was extracted several times and dried over anhydrous MgSO _4, and then distilled under reduced pressure to obtain a bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid represented by the following Chemical Formula 3 as a pure white solid (yield: 98%).

<Formula 3>

Example 2 Synthesis of Dibutylbutyl Bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate

1 mole of bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid synthesized in Example 1 was dissolved in a reactor, dissolved in 500 g of tetrahydrofuran solvent, and cooled to -10 ° C. . After adding 2 moles of SOCl ₂ to the mixture slowly for 1 hour, 2 moles of tert-butanol was added and allowed to react for about 2 hours while stirring. After completion of the reaction, the temperature is gradually increased to room temperature and allowed to react for 6 hours. After completion of the reaction, the solvent was removed using a rotary middle streamer, and distilled under reduced pressure to obtain pure butyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate of formula 4 (yield: 81 %).

<Formula 4>

Example 3 Synthesis of Ditetrahydropyranyl Bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate

1 mole of bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid synthesized in Example 1 was added to the reactor as a starting material, and then dissolved in 500 g of tetrahydrofuran solvent and the temperature was reduced to -10 ° C. Cool. Then, 0.02 mol of p-toluenesulfonic acid was slowly added thereto, stirred for 1 hour, and then, 2 mol of 3,4-dihydro-2H-pyran was added dropwise as the reactant, followed by reaction for about 2 hours. After that, the temperature is gradually increased to room temperature and allowed to react for another 5 hours. After completion of the reaction, the solvent was removed using a rotary distillation, followed by distillation under reduced pressure to obtain ditetrahydropyranyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate of the following Chemical Formula 5 (yield) : 75%).

<Formula 5>

Example 4 Synthesis of Ditetrahydrofuranyl Bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate

Ditetrahydrofuranyl bicyclo of the following Chemical Formula 6 was subjected to the same procedure as in Example 3 except that dihydrofuran was used instead of 3,4-dihydro-2H-pyran as the reactant. 2.2.2] oct-5-ene-2,3-dicarboxylate was obtained (yield: 80%).

<Formula 6>

Example 5

Synthesis of 1,1'-diethoxyethyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate

1.1'-diethoxyethyl bicyclo of Chemical Formula 7 was carried out in the same manner as in Example 3, except that ethyl vinyl ether was used instead of 3,4-dihydro-2H-pyran as the reactant. [2.2.2] Oct-5-ene-2,3-dicarboxylate was obtained (yield: 79%).

<Formula 7>

Example 6

Synthesis of 1,1'-dibutylbutoxyethyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate

Except for using tertiary butyl vinyl ether instead of 3,4-dihydro-2H-pyran as the reaction material in the same manner as in Example 3 in the pure state 1,1 '-diet Sherylbutoxyethyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate was obtained (yield: 73%).

<Formula 8>

Preparation of Photoresist Polymer

The present inventors also prepared a polymer comprising the monomer of the formula (2). At this time, it is preferable to use maleic anhydride as the second monomer in order to facilitate the coupling between the monomers of the formula (2).

In addition, it is preferable to increase the adhesion between the substrate and the photoresist pattern by using the compound of formula (9) having a hydroxy group as the third monomer.

<Formula 9>

Wherein R ₅ is hydroxyethyl or hydroxypropyl.

On the other hand, it is more preferable to further include bicyclo [2.2.2] oct-5-ene dicarboxylic acid as the fourth monomer separately from the first monomer.

Preferred photoresist copolymers according to the present invention include compounds represented by the following general formula (10).

<Formula 10>

Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms,

Wherein at least one of R ₁ and R ₂ is substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, R ₅ is hydroxyethyl or hydroxypropyl, m is It is an integer chosen from 0-3, and a: b: c: d = 10-80 mol%: 10-80 mol%: 0-70 mol%: 10-80 mol%.

It is preferable that the molecular weight of the said polymer resin for photoresists is 3,000-100,000.

The photoresist polymer according to the present invention is prepared by radically polymerizing each monomer in the presence of a polymerization initiator. As the radical polymerization method, bulk polymerization or solution polymerization may be used. Polymerization initiators include 2,2, -azobisisobutyronitrile (AIBN), benzoyl peroxide, acetyl peroxide, lauryl peroxide or t-butyl peroxide. Examples of the solvent used in the polymerization include tetrahydrofuran, cyclohexane, toluene, benzene, methyl ethyl ketone, dioxane and dimethylformamide. The polymerization is carried out for 4 to 24 hours at a temperature of 60 to 75 ℃ under nitrogen or argon atmosphere. However, the present invention is not limited to these polymerization conditions.

Example 7 Poly (Diethylbutyl Bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [ 2,2.2] Synthesis of Oct-5-ene-2,3-dicarboxylic acid / maleic anhydride

0.85 mol of dibutyl butyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate, 0.1 mol of 2-hydroxyethyl 5-norbornene-2-carboxylate, bicyclo [2.2. 2] After putting 0.05 mol of oct-5-ene-2,3-dicarboxylic acid and 1 mol of maleic hydride in a tetrahydrofuran solvent, 5.5 g of AIBN was added to a polymerization reagent and stirred. The polymerization temperature was fixed at 67 ° C. and polymerized under nitrogen atmosphere for 10 hours. After completion of the polymerization reaction, the polymer was precipitated in an ethyl ether solvent and dried in vacuo to obtain a copolymer of formula 11 in a pure state (yield 32%).

<Formula 11>

Example 8

Poly (ditetrahydropyranyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [2, 2.2] Synthesis of oct-5-ene-2,3-dicarboxylic acid / maleic anhydride)

Ditetrahydropyranyl bicyclo [2.2.2] oct-5-ene-2,3-dicar instead of dietarybutyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate Except that the addition of the carboxylate was carried out in the same procedure as in Example 7 to obtain a polymer of formula 12 (yield 30.5%).

<Formula 12>

Example 9 poly (ditetrahydrofuranyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / ratio Synthesis of Cyclo [2,2.2] oct-5-ene-2,3-dicarboxylic acid / maleic anhydride)

Ditetrahydrofuranyl bicyclo [2.2.2] oct-5-ene-2,3-dicar instead of dietarybutyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate Except that the addition of the carboxylate was carried out in the same procedure as in Example 7 to obtain a polymer of the formula (13) (yield 30.5%).

<Formula 13>

Example 10 poly (1,1'-diethoxyethyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxyl Synthesis of Rate / Bicyclo [2,2.2] oct-5-ene-2,3-dicarboxylic acid / maleic anhydride)

1,1'-diethoxyethyl bicyclo [2.2.2] oct-5-ene-2,3 instead of dietarybutyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate A polymer of the following Chemical Formula 14 was obtained in the same manner as in Example 7, except that dicarboxylate was added (yield 31.5%).

<Formula 14>

Example 11 Poly (1,1'-Diethylbutoxyethyl 5-norbornene-2-carboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [2,2.2] Synthesis of Oct-5-ene-2,3-dicarboxylic acid / maleic anhydride

Add 1,1'-ethoxyethyl 5-norbornene-2,3-dicarboxylate instead of dietary butyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate Except for the same procedure as in Example 7, to obtain a polymer of formula 15 (yield 32%).

<Formula 15>

Synthesis of Photoresist Composition and Forming Fine Pattern Using the Same

The photoresist polymer of Formula 10 prepared as described above is useful for forming a fine pattern of a semiconductor device. The present inventors prepared a photoresist composition by mixing the polymer of Formula 10 with a conventional organic solvent and a photoacid generator.

The photoacid generator may use a sulfide-based or onium salt-based compound, and specifically, triphenylsulfonium triflate or dibutylnaphthylsulfonium triflate. The photoacid generator is used in an amount of 0.05 to 10% by weight of the used photoresist resin. When it is used at 0.05 wt% or less, the photosensitive sensitivity of the photoresist becomes weak. When it is used at 10 wt% or more, the photoacid generator absorbs a lot of ultraviolet rays, thereby obtaining a pattern having a bad cross section.

As the organic solvent, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, cyclohexanone, propylene glycol methyl ether acetate and the like can be used. The solvent is used in an amount of 200 to 1000% by weight of the photoresist resin used to obtain a photoresist of a desired thickness.

Meanwhile, a fine pattern was formed on a semiconductor substrate using the photoresist composition according to the present invention.

First, the photoresist composition according to the present invention is spin coated on a silicon wafer and then baked. Subsequently, after exposure with an exposure apparatus using ArF light, it is post-baked for about 1 to 2 minutes. In this case, the soft bake and post bake process may be performed at 70 to 200 ° C. As the exposure source, KrF, E-beam, EUV (extremely ultraviolet), ion beam, or the like may be used.

Then, it developed in 2.38 wt% TMAH aqueous solution, and obtained the fine pattern. The obtained fine pattern exhibited excellent adhesion and sensitivity which did not collapse even at a high density of 0.15 µm or less. EMBODIMENT OF THE INVENTION Hereinafter, although this invention is demonstrated concretely based on an Example, it is not understood that the technical scope of this invention is limited to these.

Example 12

10 g of the polymer of Example 7 and 0.12 g of triphenylsulfonium triflate were dissolved in 60 g of ethyl 3-ethoxypropionate, and then filtered through a 0.10 μm filter to prepare a photoresist composition.

The composition is spin coated onto a silicon wafer and then baked at 110 ° C. for 90 seconds. After baking, the resultant is exposed to light with an ArF laser exposure apparatus and then baked again at 110 ° C for 90 seconds. Subsequently, the resultant was developed in a 2.38 wt% TMAH aqueous solution for 40 seconds, thereby obtaining a 0.13 μm L / S pattern as shown in FIG. 1.

Example 13

A 0.14 µm L / S pattern was obtained in the same manner as in Example 12 except that the polymer of Example 8 was used.

Example 14

A 0.14 µm L / S pattern was obtained in the same manner as in Example 12 except that the polymer of Example 9 was used.

Example 15

A 0.14 μm L / S pattern as shown in FIG. 2 was obtained in the same manner as in Example 12 except that the polymer of Example 10 was used.

Example 16

A 0.14 μm L / S pattern as shown in FIG. 3 was obtained in the same manner as in Example 12 except that the polymer of Example 11 was used.

The photoresist polymer according to the present invention is excellent in etch resistance because the backbone is composed of a bicycloalkene monomer, and includes a first monomer having two carboxylate groups, and thus has excellent photosensitivity and a hydroxy group. Including the third monomer having a good adhesion between the substrate and the photoresist pattern has a high resolution without falling down pattern even in a high-density device, and because the light absorption rate is low in the extreme wavelength can be formed finer fine pattern, especially ArF light source It is suitable for the photolithography process to be used.

Claims (21)

A photoresist polymer comprising a monomer of the formula (2). <Formula 2> Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is 1 carbon atom Substituted or unsubstituted linear or branched alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of 10 to 10, m is an integer selected from 0 to 3. The method of claim 1, Wherein said polymer comprises maleic hydride as a second monomer. The method according to claim 1 or 2, The polymer is characterized in that it further comprises a compound of formula (9) as a third monomer. <Formula 9> Wherein R ₅ is hydroxyethyl or hydroxypropyl. The method of claim 1, Wherein said polymer further comprises bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid as a fourth monomer. The method of claim 1, The polymer is a polymer, characterized in that the compound of formula (10). <Formula 10> Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is carbon 1 to 10 substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl, R ₅ is hydroxyethyl or hydroxypropyl, m is an integer selected from 0 to 3, a: b: c: d = 10-80 mol%: 10-80 mol%: 0-70 mol%: 10-80 mol%. The method of claim 5, wherein The polymer has a molecular weight of 3,000 to 100,000 characterized in that the polymer. The method of claim 5, wherein The polymer is poly (dibutylbutyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [2.2 .2] oct-5-ene-2,3-dicarboxylic acid / maleic hydride), Poly (ditetrahydropyranyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [2.2. 2] oct-5-ene-2,3-dicarboxylic acid / maleic hydride), Poly (ditetrahydrofuranyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [2.2. 2] oct-5-ene-2,3-dicarboxylic acid / maleic hydride), Poly (1,1'-diethoxyethyl bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid / maleic anhydride) and Poly (1,1'-dibutyoxyethyl 5-norbornene-2,3-dicarboxylate / 2-hydroxyethyl 5-norbornene-2-carboxylate / bicyclo [2.2.2] oct -5-ene-2,3-dicarboxylic acid / maleic hydride). (a) A monomer of formula (2), a maleic hydride, a compound of formula (9), and optionally a bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid are added to the organic solvent. Adding step, (b) adding a polymerization initiator to the resultant solution to polymerize the reaction. <Formula 2> Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is 1 carbon atom Substituted or unsubstituted linear or branched alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of 10 to 10, m is an integer selected from 0 to 3. <Formula 9> Wherein R ₅ is hydroxyethyl or hydroxypropyl. The method of claim 8, Wherein said polymerization initiator is selected from the group consisting of 2,2, -azobisisobutyronitrile (AIBN), benzoyl peroxide, acetyl peroxide, lauryl peroxide and t-butyl peroxide. The method of claim 8, The organic solvent is selected from the group consisting of tetrahydrofuran, toluene, benzene, methylethylketone and dioxane. A photoresist composition comprising a photoresist polymer comprising a monomer of the formula (2), a photoacid generator, and an organic solvent. <Formula 2> Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is 1 carbon atom Substituted or unsubstituted linear or branched alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of 10 to 10, m is an integer selected from 0 to 3. The method of claim 11, The photoresist polymer is a photoresist composition, characterized in that the compound of formula (10). <Formula 10> Wherein R ₁ and R ₂ are each hydrogen or substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl having 1 to 10 carbon atoms, wherein at least one of R ₁ and R ₂ is carbon 1 to 10 substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl, R ₅ is hydroxyethyl or hydroxypropyl, m is an integer selected from 0 to 3, a: b: c: d = 10-80 mol%: 10-80 mol%: 0-70 mol%: 10-80 mol%. The method of claim 11, Said photoacid generator is triphenylsulfonium triflate or dibutyl naphthylsulfonium triflate. The method of claim 11, The content of the photoacid generator is a photoresist composition, characterized in that 0.05 to 10% by weight of the polymer. The method of claim 11, The organic solvent is a photoresist composition, characterized in that selected from the group consisting of ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, cyclohexanone and propylene glycol methyl ether acetate. The method of claim 11, The content of the organic solvent is a photoresist composition, characterized in that 200 to 1000% by weight of the polymer. (a) coating the photoresist composition of claim 11 onto a wafer; (b) exposing the wafer; (c) developing the resultant with a developer to obtain a predetermined pattern. The method of claim 17, And performing a baking process before and / or after exposure in step (b), respectively. The method of claim 18, The baking process is a photoresist pattern forming method, characterized in that performed at 70 ~ 200 ℃. The method of claim 17, The exposure process is a photoresist pattern forming method characterized in that it is performed using ArF, KrF, E-beam, X-ray, EUV, DUV or ion beam. A semiconductor device manufactured by the method of claim 17.