KR100604780B1 - Photosensitive polymer having alicyclic compound and acetal functional group in its backbone and photosensitive copolymer including the polymer - Google Patents

Abstract

A photosensitive polymer having an alicyclic compound and an acetal functional group in a backbone, a photosensitive copolymer comprising the same, and a resist composition obtained therefrom are disclosed. The photosensitive polymer which concerns on this invention has a following formula, and a weight average molecular weight is 5,000-100,000.

Wherein R ₁ is hydrogen or a methyl group, R ₂ and R ₃ are each a hydrogen, methyl, ethyl or methoxy group, and R ₄ is a C ₁ to C ₂₀ aliphatic or alicyclic saturated compound.

Description

Photosensitive polymer having alicyclic compound and acetal functional group in the backbone and photosensitive copolymer comprising the same {Photosensitive polymer having alicyclic compound and acetal functional group in its backbone and photosensitive copolymer including the polymer}

The present invention relates to a chemically amplified resist composition, and more particularly, to a photosensitive polymer having a backbone having a cyclic structure, a photosensitive copolymer comprising the same, and a resist composition for an ArF excimer laser obtained therefrom.

As the semiconductor manufacturing process becomes complicated and the degree of integration of semiconductor devices increases, fine pattern formation is required. Moreover, in devices with a semiconductor device having a capacity of 1 gigabit or more, a pattern size of 0.2 μm or less is required for the design rule, and thus there is a limit to using a resist material using a conventional KrF excimer laser (248 nm). have. Thus, a lithography technique using ArF excimer laser (193 nm), a new energy exposure source, has emerged.

Such a resist material used in lithography using an ArF excimer laser has many problems to be commercialized compared to conventional resist materials. The most common problem is the polymer's transmittance and resistance to dry etching.

Acrylic or methacrylic polymers have been mainly used as a general ArF resist known to date. Among them, poly (methyl methacrylate-tert -butyl methacrylate-methacrylic acid) which is an initial terpolymer system of IBM Corporation is representative. A serious problem with these polymers is their poor resistance to dry etching.

Accordingly, in order to increase the resistance to dry etching, an alicyclic compound, for example, an isobornyl group, adamantyl group, or tricyclo, which is a material having strong resistance to dry etching The introduction of the decycloyl group (tricyclodecanyl group) into the backbone of the polymer is also used. However, they are still poorly resistant to dry etching.

In addition, polymers containing such alicyclic compounds have poor adhesion to the membrane. Accordingly, there is a problem in that a resist pattern is lifted during the development process for forming a resist pattern in performing a photolithography process using a resist composition manufactured using the above polymer.

It is therefore an object of the present invention to provide a photosensitive polymer which contains an alicyclic compound in the backbone of the polymer and at the same time has an acetal functional group which can be readily decomposed under an acid catalyst.

Another object of the present invention is to provide photosensitive copolymers comprising the polymer.

It is still another object of the present invention to provide a resist composition comprising the photosensitive polymer described above so that sufficient resistance to dry etching and adhesion to film quality can be secured in a lithography process using an ArF excimer laser.

In order to achieve the above object, the present invention has the following formula, and provides a photosensitive polymer having a weight average molecular weight of 5,000 to 100,000.

Wherein R ₁ is hydrogen or a methyl group, R ₂ and R ₃ are each a hydrogen, methyl, ethyl or methoxy group, and R ₄ is a C ₁ to C ₂₀ aliphatic or alicyclic saturated compound.

Preferably, R ₄ is adamantyl group, adamantanemethyl group, adamantaneethyl group, norbornyl group, norbornanemethyl group, isobornyl group, menthyl group, isomentyl group, decahydronaphthyl group, naphthyl group, It is a naphthalene methyl group or a naphthalene ethyl group.

In order to achieve the above another object, the present invention provides an acrylate derivative or methacryl having a photosensitive polymer as defined above and an alcohol, carboxylic acid, ether, cyclic ether, crown ether, lactone, acetal, or ketal group. Late derivatives; Hydroxy styrene; Vinylpyrrolidinone; And it provides a photosensitive copolymer consisting of a comonomer (cononomer) consisting of any one selected from the group consisting of maleic anhydride, contained in an amount of 10 to 80 mol%.

The weight average molecular weight of the said copolymer is 5,000-100,000.

For example, (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, methyl (meth) acrylate or ethylene glycol methyl ether (meth) acrylate can be used as the comonomer, in which case The monomer may be contained in an amount of 10 to 70 mol% in the copolymer.

Or (meth) acryloyloxy-γ-butyrolactone, tetrahydrofurfuryl (meth) acrylate, 2,2-dimethyl-1,3-dioxolane-4-methyl (solketal) as the comonomer (Meth) acrylate or (meth) acryloyloxymethyl-12-crown-4 may be used, in which case the comonomer may be contained in an amount of 10 to 70 mole percent in the copolymer.

Or 1,2: 3,4-di- O -isopropylidene-D-galactopyranosyl (meth) acrylate, diacetone-D-glucosyl (meth) acrylate or 1,2 as the comonomer : 5,6-di- O -cyclohexylidene-α-glucofuranosyl (meth) acrylate can be used, in which case the comonomer is contained in the copolymer in an amount of 10 to 50 mol%. Can be.

Alternatively, maleic anhydride, hydroxystyrene, vinyl benzoic acid or vinylpyrrolidinone may be used as the comonomer, in which case the comonomer may be present in the copolymer in an amount of 10 to 80 mol%. It may be contained.

In order to achieve the above another object, the present invention provides a resist composition consisting of the photosensitive polymer as defined above, a photoacid generator (PAG), and an organic base.

The amount of the PAG in the resist composition is 1 to 15% by weight based on the weight of the photosensitive polymer, and the amount of the organic base is 0.01 to 2% by weight based on the weight of the photosensitive polymer.

As the PAG, triarylsulfonium salts, diaryliodonium salts or sulfonates can be used.

Triethylamine, triisobutylamine, triisooctylamine, diethanolamine or triethanolamine can be used as the organic base.

The resist composition may further include 50 to 500 ppm of a surfactant. As the surfactant, polyether, poly (ethylene glycol) or polysulfonate can be used.

According to the present invention, a photosensitive polymer containing an alicyclic compound in a backbone and having an acetal functional group that can be easily decomposed under an acid catalyst and a resist composition comprising the same, It is possible to improve the adhesive properties and to ensure sufficient resistance to dry etching.

Next, a preferred embodiment of the present invention will be described in detail.

Example 1

Synthesis of 1-chloromethyl adamantyl ether

In a round flask, sodium hydride (4.8 g, 55% NaH) and 1-adamantanol (15 g, 0.1 mole) were reacted in anhydrous THF (tetrahydrofuran) (150 mL), followed by excess bromo Chloromethane (52 g, 0.4 mol) was slowly dropped and reacted at room temperature for about 12 hours.

After the reaction was completed, excess THF was volatilized and the reaction was poured into excess water and neutralized with HCl. Thereafter, the mixture was extracted using diethyl ether, and then dried using MgSO ₄ .

After distilling off diethyl ether, the product was recovered from the crude product by vacuum distillation (yield 75%).

Example 2

Synthesis of 1-chloroethyl-1-adamantyl ether

Sodium hydride (4.8 g, 55% NaH) and 1-adamantanol (15 g, 0.1 mol) were reacted in anhydrous THF (150 mL), followed by 1-bromo-1-chloroethane (29 g, 0.2 mol). Was added slowly, and reacted at room temperature for about 12 hours.

After the reaction was completed, the product was recovered in the same manner as in Example 1 (yield 75%).

Example 3

Synthesis of 2-chloropropyl-1-adamantyl ether

After reacting sodium hydride (4.8 g, 55% NaH) with 1-adamantanol (15 g, 0.1 mole) in anhydrous THF (150 mL), 2,2-dichloropropane (34 g, 0.3 mole) was slowly added thereto. Then, the reaction was performed at a temperature of about 45 ° C. for about 12 hours.

After the reaction was completed, the product was recovered in the same manner as in Example 1 (yield 70%).

Example 4

Synthesis of 1-adamantyloxymethyl methacrylate

In a round flask, methacrylic acid (9.6 g, 0.11 mol) and triethylamine (12 g, 0.12 mol) were reacted in methylene chloride (150 mL), followed by chloromethyl-1-adamantyl ether. (20 g, 0.1 mol) was slowly dropped, and the obtained mixture was reacted at reflux for about 12 hours.

After the reaction was completed, the reaction was poured into excess water and neutralized with HCl. Thereafter, the mixture was extracted using methylene chloride and purified using colum chromatography (ethyl acetate: hexane = 1: 3) to recover the product (yield 80%).

Example 5

Synthesis of 1-adamantyloxy-1-ethyl methacrylate

Methacrylic acid (9.6 g, 0.11 mole) and triethylamine (12 g, 0.12 mole) were reacted in methylene chloride (150 mL), and the 1-chloroethyl-1-adamantyl ether synthesized in Example 2 was added thereto. (22 g, 0.1 mol) was slowly dropped and the resulting mixture was reacted for about 12 hours at reflux.

After the reaction was completed, the product was recovered in the same manner as in Example 4 (yield 80%).

Example 6

Synthesis of 1-adamantyloxy-2-propyl methacrylate

The reaction was carried out in the same manner as in Example 4 using 2-chloropropyl-1-adamantyl ether (0.1 mol) synthesized in Example 3, and the product was recovered in the same manner as in Example 4. 81%).

Example 7

Synthesis of Isobornyloxymethyl Methacrylate

After chloromethyl isobornyl ether (0.1 mol) was synthesized in the same manner as in Example 1, the product was synthesized and purified in the same manner as in Example 4 (yield 82%).

Example 8

Synthesis of Norbornyloxymethyl Methacrylate

After chloromethyl norbornyl ether (0.1 mol) was synthesized in the same manner as in Example 1, the product was synthesized and purified in the same manner as in Example 4 (yield 82%).

Example 9

Synthesis of Decahydro-2-naphthyloxymethyl methacrylate

After chloromethyl decahydro-2-naphthyl ether (0.1 mol) was synthesized in the same manner as in Example 1, the product was synthesized and purified in the same manner as in Example 4 (yield 82%).

Example 10

Synthesis of Menthyloxymethyl Methacrylate

The reaction was carried out in the same manner as in Example 4 using chloromethyl menthyl ether (0.1 mol), and then the product was purified in the same manner as in Example 4 (yield 80%).

Example 11

Synthesis of Homopolymer

The monomer (5 g, 20 mmol) and AIBN (azobis (isobutyronitrile)) (0.13 g, 0.8 mol) synthesized in Example 4 were dissolved in anhydrous dioxane (20 g), followed by freezing with liquid nitrogen. Degassing was performed. The reaction was then polymerized at a temperature of 70 ° C. for about 24 hours.

After the end of the polymerization, the reaction was precipitated by slowly dropping the excess in n-hexane, and the precipitate was dissolved in THF again, reprecipitated in n-hexane and dried in a vacuum oven at 50 ° C. for 24 hours (yield) 85%).

At this time, the weight average molecular weight (Mw) of the obtained product was 12,600, and polydispersity was 2.1.

Example 12

Synthesis of Homopolymer

After dissolving the monomer (10 mmol) and AIBN (0.4 mol) synthesized in Example 5 in dioxane anhydride (monomer x 4 times), the polymer was synthesized in the same manner as in Example 11 (yield 83%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,400, and polydispersity was 2.2.

Example 13

Synthesis of Homopolymer

After dissolving the monomer (10 mmol) and AIBN (0.4 mol) synthesized in Example 8 in dioxane anhydride (monomer x 4 times), the polymer was synthesized in the same manner as in Example 11 (yield 85%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,000, and polydispersity was 2.1.

Example 14

Synthesis of Homopolymer

After dissolving the monomer (10 mmol) and AIBN (0.4 mol) synthesized in Example 9 in dioxane anhydride (monomer x 4 times), the polymer was synthesized in the same manner as in Example 11 (yield 83%).

At this time, the weight average molecular weight (Mw) of the obtained product was 12,700, and polydispersity was 2.2.

Example 15

Synthesis of Homopolymer

After dissolving the monomer (10 mmol) and AIBN (0.4 mol) synthesized in Example 10 in dioxane anhydride (monomer x 4 times), the polymer was synthesized in the same manner as in Example 11 (yield 81%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,700, and polydispersity was 2.2.

Example 16

Synthesis of Copolymer

Example 16-1

Synthesis of Copolymers (R = γ-butyrolactone)

Monomer (7.5 g, 30 mmol) and α-methacryloyloxy-γ-butyrolactone (3.4 g, 20 mmol) synthesized in Example 4 were combined with AIBN (0.33 g, 2 mmol) with dioxane anhydride ( After dissolving in 45 g), degassing was performed by freezing using liquid nitrogen. The reaction was then polymerized at a temperature of 70 ° C. for about 24 hours.

After the end of the polymerization, the reaction was precipitated by slowly dropping the excess in n-hexane, and the precipitate was dissolved in THF again, reprecipitated in n-hexane and dried in a vacuum oven at 50 ° C. for 24 hours (yield) 80%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,600, and polydispersity was 2.2.

Example 16-2

Synthesis of Copolymer (R = tetrahydrofurfuryl)

Monomer (7.5 g, 30 mmol) and tetrahydrofurfuryl methacrylate (5.1 g, 30 mmol) synthesized in Example 4 were combined with AIBN (0.39 g, 2.4 mmol) in the same manner as in Example 16-1. After the polymerization, the polymer was synthesized in the same manner as in Example 16-1 (yield 83%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,200, and polydispersity was 2.1.

Example 16-3

Synthesis of Copolymer (R = 2,2-dimethyl-1,3-dioxolane-4-methyl)

2,2-dimethyl-1,3-dioxolane-4-methyl (solketal) methacrylate (6 g, 20 mmol) and the monomer synthesized in Example 4 (7.5 g, 30 mmol) were prepared using AIBN (0.33 g, 2 mmol) was polymerized in the same manner as in Example 16-1, and then a polymer was synthesized in the same manner as in Example 16-1 (yield 85%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,100, and polydispersity was 2.2.

Example 16-4

Synthesis of Copolymer (R = 2-methyl-12-crown-4)

2-methylacryloyloxymethyl-12-crown-4 (5.5 g, 20 mmol) and the monomer synthesized in Example 4 (7.5 g, 30 mmol) with AIBN (0.33 g, 2 mmol) in Example 16 After the polymerization in the same manner as in -1, the polymer was synthesized in the same manner as in Example 16-1 (yield 85%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,500, and polydispersity was 2.2.

Example 16-5

Synthesis of Copolymer (R = Ethylene Glycol Methyl Ether)

Ethylene glycol methyl ether methacrylate (4.3 g, 30 mmol) and the monomer synthesized in Example 4 (7.5 g, 30 mmol) were combined with AIBN (0.39 g, 2.4 mmol) in the same manner as in Example 16-1. After the polymerization, the polymer was synthesized in the same manner as in Example 16-1 (yield 85%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,700, and polydispersity was 2.2.

Example 16-6

Synthesis of Copolymer

4-hydroxystyrene monomer (9 g, 75 mmol) and the monomer (6.3 g, 25 mmol) synthesized in Example 4 were polymerized with AIBN (0.67 g, 4 mmol) in the same manner as in Example 16-1. Next, a polymer was synthesized in the same manner as in Example 16-1 (yield 83%).

At this time, the weight average molecular weight (Mw) of the obtained product was 14,100, and polydispersity was 2.3.

Example 17

Synthesis of Copolymer

1,2: 3,4-di- O -isopropylidene-D-galactopyranosyl methacrylate (4.9 g, 15 mmol) and the monomer synthesized in Example 4 (8.8 g, 35 mmol) were prepared using AIBN ( 0.33 g) was polymerized in the same manner as in Example 16-1, and then a polymer was synthesized in the same manner as in Example 16-1 (yield 81%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,700, and polydispersity was 2.2.

Example 18

Synthesis of Copolymer

Diacetone-D-glucosyl methacrylate (4.9 g, 15 mmol) and the monomer synthesized in Example 4 (8.8 g, 35 mmol) with AIBN (0.33 g, 2 mmol) in Example 16-1 and After the polymerization in the same manner, a polymer was synthesized in the same manner as in Example 16-1 (yield 81%).

At this time, the weight average molecular weight (Mw) of the obtained product was 14,100, and polydispersity was 2.2.

Example 19

Synthesis of Copolymer

1,2: 5,6-di- O -cyclohexylidene-α-D-glucofuranosyl methacrylate (8.2 g, 20 mmol) and the monomer synthesized in Example 4 (7.5 g, 30 mmol) The polymer was polymerized with AIBN (0.33 g, 2 mmol) in the same manner as in Example 16-1, and then the polymer was synthesized by the same method as in Example 16-1 (yield 80%).

At this time, the weight average molecular weight (Mw) of the obtained product was 13,100, and polydispersity was 2.2.

Example 20

Synthesis of Copolymer

 The polymerization was carried out in the same manner as in Example 16-1 to prepare a copolymer of the monomers synthesized in Examples 5 to 10 with comonomers as listed below. A polymer was synthesized in the same manner as in Example 16-1.

The following shows the structure of the comonomers used in this example.

Example 21

Resist Compositions for Pattern Forming Process

The polymers synthesized in Examples 11 to 20 (1.0 g) were mixed with propylene glycol monomethyl ether acetate (PGMEA) with triphenylsulfonium triflate (20 mg) as PAG and triisobutylamine (2 mg) as organic base. (6.0 g) completely dissolved in solution. Thereafter, the solution was filtered using a 0.2 μm membrane filter to obtain a resist composition. Thereafter, a silicon wafer having a lower film quality formed of a silicon oxide film on the upper surface thereof is prepared, the silicon wafer is treated with hexamethyldisilazane (HMDS), and then the resist composition is applied to the silicon oxide film on the silicon wafer. Coated to a thickness of 0.4 μm.

The wafer coated with the resist composition is pre-baked for 60 to 120 seconds in a temperature range of 100 to 130 ° C., and has a KrF excimer laser having a numerical aperture (NA) of 0.45 or a numerical aperture (NA) of 0.6. After exposure using an ArF excimer laser, PEB (post-exposure baking) was performed for 60 to 120 seconds at a temperature range of 100 to 140 ° C.

Thereafter, development was performed for about 20 to 60 seconds using a 2.38 wt% tetramethylammonium hydroxide (TMAH) solution. The resulting resist pattern was used as a mask, and the lower film quality consisting of the silicon oxide film was etched using a specific etching gas. Subsequently, the resist pattern remaining on the wafer was removed using a stripper to form a desired silicon oxide film pattern.

Example 22

Resist composition

Using the polymer synthesized in Example 11 (1.0 g), a resist composition was prepared in the same manner as in Example 21, and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked for 90 seconds at a temperature of 110 ° C, exposed using a KrF excimer laser having a numerical aperture (NA) of 0.45, and then PEB for 90 seconds at a temperature of 110 ° C. Was carried out.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

Example 23

Resist composition

A resist composition was prepared in the same manner as in Example 21 using the polymer synthesized in Example 13 (1.0 g), triphenylsulfonium triflate (20 mg) as PAG, and triethanolamine (2 mg) as an organic base. The resulting resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked for 90 seconds at a temperature of 110 ° C, exposed using a KrF excimer laser having a numerical aperture (NA) of 0.45, and then PEB for 90 seconds at a temperature of 120 ° C. Was carried out.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

Example 24

Resist composition

Using the polymer synthesized in Example 15 (1.0 g), a resist composition was prepared in the same manner as in Example 21, and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked at a temperature of 120 ° C. for 90 seconds, and exposed using a KrF excimer laser having a numerical aperture (NA) of 0.45, followed by 90 seconds at a temperature of 120 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

Example 25

Resist composition

Using the polymer synthesized in Example 16-1 (1.0 g), a resist composition was prepared in the same manner as in Example 21, and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked at a temperature of 120 ° C. for 90 seconds, and exposed using an ArF excimer laser having a numerical aperture (NA) of 0.6, followed by 90 seconds at a temperature of 110 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

It was confirmed that a 0.3 μm line-and-space pattern was obtained when the exposure dose amount was set to about 14 mJ / cm ² .

Example 26

Resist composition

A resist composition was prepared in the same manner as in Example 21 using the polymer synthesized in Example 16-2 (1.0 g), triphenylsulfonium triflate (20 mg) as PAG, and triethanolamine (2 mg) as an organic base. The prepared and obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked at a temperature of 120 ° C. for 90 seconds, and exposed using an ArF excimer laser having a numerical aperture (NA) of 0.6, followed by 90 seconds at a temperature of 110 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

It was confirmed that a 0.3 μm line-and-space pattern was obtained when the exposure dose amount was set to about 16 mJ / cm ² .

Example 27

Resist composition

Using the polymer synthesized in Example 16-4 (1.0 g), a resist composition was prepared in the same manner as in Example 21, and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked at a temperature of 120 ° C. for 90 seconds, and exposed using an ArF excimer laser having a numerical aperture (NA) of 0.6, followed by 90 seconds at a temperature of 120 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

It was confirmed that a 0.3 μm line-and-space pattern was obtained when the exposure dose amount was set to about 13 mJ / cm ² .

At this time, the exposure mechanism of the resist composition obtained from the copolymer synthesized in Example 16-4 can be represented as in Scheme 1.

Example 28

Resist composition

Polymer synthesized in Example 16-5 (1.0 g), triphenylsulfonium triflate (10 mg) and methoxydiphenyl iodonium triflate (10 mg) as PAG, and triisobutylamine (2 mg) as organic base Using the same method as in Example 21 to prepare a resist composition and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked at a temperature of 120 ° C. for 90 seconds, and exposed using an ArF excimer laser having a numerical aperture (NA) of 0.6, followed by 90 seconds at a temperature of 110 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

It was confirmed that a 0.3 µm line-and-space pattern was obtained when the exposure dose amount was set to about 15 mJ / cm ² .

Example 29

Resist composition

Using the polymer synthesized in Example 17 (1.0 g), a resist composition was prepared in the same manner as in Example 21, and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked at a temperature of 120 ° C. for 90 seconds, and exposed using an ArF excimer laser having a numerical aperture (NA) of 0.6, followed by 90 seconds at a temperature of 120 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

Example 30

Resist composition

Using the polymer synthesized in Example 18 (1.0 g), a resist composition was prepared in the same manner as in Example 21, and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked for 90 seconds at a temperature of 110 ° C., exposed using an ArF excimer laser having a numerical aperture (NA) of 0.6, and then for 90 seconds at a temperature of 110 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

Example 31

Resist composition

Using the polymer synthesized in Example 19 (1.0 g), a resist composition was prepared in the same manner as in Example 21, and the obtained resist composition was coated on a wafer. Thereafter, the wafer coated with the resist composition was prebaked at a temperature of 120 ° C. for 90 seconds, and exposed using an ArF excimer laser having a numerical aperture (NA) of 0.6, followed by 90 seconds at a temperature of 110 ° C. PEB was performed.

Thereafter, it was developed for about 60 seconds using a 2.38 wt% TMAH solution to form a resist pattern.

The photosensitive polymer according to the present invention contains an alicyclic compound in the backbone and has an acetal functional group or a ketal functional group which can be easily decomposed under an acid catalyst. Therefore, the problem with the adhesive property which the polymer containing an existing alicyclic compound has can be reduced by introduction of an acetal group.

In addition, the polymer according to the present invention may also be present in the form of a homopolymer or a copolymer.

Therefore, the resist composition made of the polymer according to the present invention can ensure sufficient resistance to dry etching.

In addition, the polymer according to the present invention may be made of a copolymer composed of various comonomers (comonomer) to improve the adhesive properties, the resist composition made of such a polymer is excellent in adhesion properties to the film.                     

Therefore, the polymer and the resist composition using the same according to the present invention can exhibit very good lithography performance in any type of lithography process, and can be very useful for manufacturing future next-generation semiconductor devices.

The present invention has been described in detail with reference to preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications can be made by those skilled in the art within the scope of the technical idea of the present invention. Do.

Claims (3)

The photosensitive polymer which has a following formula and whose weight average molecular weight is 5,000-100,000.

Wherein R ₁ is hydrogen or methyl, R ₂ and R ₃ are each hydrogen, methyl, ethyl or methoxy, R ₄ is adamantyl, norbornyl, isobornyl, menthyl or decahydronaphthyl Term. delete The photosensitive polymer of claim 1, Acrylate derivatives or methacrylate derivatives having alcohol, carboxylic acid, ether, cyclic ether, crown ether, lactone, acetal, or ketal groups; Hydroxystyrene; Vinylpyrrolidinone; And a comonomer composed of any one selected from the group consisting of maleic anhydride and contained in an amount of 10 to 80 mol%.