BLOCK COPOLYMER

Abstract

The present application provides a block copolymer and uses thereof. The block copolymer of the present application exhibits an excellent self-assembling property or phase separation property, can be provided with a variety of required functions without constraint and, especially, etching selectivity can be secured, making the block copolymer effectively applicable to such uses as pattern formation.

Claims

1. A block copolymer comprising a first block comprising a unit represented by Structural Formula 1 below and a second block comprising a unit represented by Structural Formula 3 below: ##STR00010## wherein, R of the Formula 1 represents a hydrogen atom or an alkyl group; X of the Formula 1 represents a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, a carbonyl group, an alkylene group, an alkenylene group, an alkynylene group, —C(═O)—X.sub.1— or —X.sub.1—C(═O)—, wherein the X.sub.1 represents an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group or an alkynylene group; Y of the Formula 1 represents a monovalent substituent that includes a ring structure to which a linear chain including 8 or more chain-forming atoms is connected; and X.sub.2 of the Formula 3 represents a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group, an alkynylene group, —C(═O)—X.sub.2— or —X.sub.2—C(═O)—, wherein the X.sub.2 represents a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group or an alkynylene group; and each of R.sub.1 to R.sub.5 of the Formula 3 independently represents a hydrogen atom, an alkyl group, a haloalkyl group, a halogen atom or a photo crosslinkable functional group, wherein one or more of the photo crosslinkable functional groups are included in positions marked as R.sub.1 to R.sub.5.

2. The block copolymer of claim 1, wherein the X represents a single bond, an oxygen atom, a carbonyl group, —C(═O)—O—, or —O—C(═O)—.

3. The block copolymer of claim 1, wherein the linear chain includes 8 to 20 chain-forming atoms.

4. The block copolymer of claim 1, wherein the chain-forming atom is carbon, oxygen, nitrogen, or sulfur.

5. The block copolymer of claim 1, wherein the chain-forming atom is carbon or oxygen.

6. The block copolymer of claim 1, wherein the ring structure of the Y is an aromatic ring structure or an alicyclic ring structure.

7. The block copolymer of claim 1, wherein the Y of the Structural Formula 1 is represented by Structural Formula 2 below:
—P-Q-Z  [Structural Formula 2] where in the Structural Formula 2, P represents an arylene group; Q represents a single bond, an oxygen atom or —NR.sub.3—, wherein the R.sub.3 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group or an aryl group; and Z represents a linear chain with 8 or more chain-forming atoms.

8. The block copolymer of claim 1, wherein the photo crosslinkable functional group is benzoylphenoxy group, alkenyloxycarbonyl group, (meth)acryloyl group or alkenyloxyalkyl group.

9. The block copolymer of claim 1, wherein one or more halogen atoms are included in the positions marked as R.sub.1 to R.sub.5 of the Structural Formula 3.

10. The block copolymer of claim 1, wherein a ratio of the unit represented by the structural formula 3 in the second block is from 0.1 mol % to 5 mol %.

11. The block copolymer of claim 1, wherein the second block further includes a structural unit represented by Structural Formula 4 below: ##STR00011## where in the Structural Formula 4, X.sub.2 represents a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group, an alkynylene group, —C(═O)—X.sub.1— or —X.sub.1—C(═O)—, wherein the X.sub.1 represents a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group or an alkynylene group; and W represents an aryl group that includes at least one halogen atom.

12. The block copolymer of claim 1, wherein the second block further includes a structural unit represented by Structural Formula 5 below: ##STR00012## where in the Structural Formula 5, X.sub.3 represents a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group, an alkynylene group, —C(═O)—X.sub.1— or —X.sub.1—C(═O)—, wherein the X.sub.1 represents a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group or an alkynylene group; and each of R.sub.a to R.sub.e independently represents a hydrogen atom, an alkyl group, a haloalkyl group or a halogen atom, wherein one or more halogen atoms are included in positions marked as R.sub.a to R.sub.e.

13. The block copolymer of claim 12, wherein 3 or more halogen atoms are included in the positions marked as R.sub.a to R.sub.e.

14. The block copolymer of claim 12, wherein 5 or more halogen atoms are included in the positions marked as R.sub.a to R.sub.e.

15. The block copolymer of claim 12, wherein the halogen atom is a fluorine atom.

16. A polymer film comprising the block copolymer of claim 1, wherein the block copolymer is self-assembled.

17. The polymer film of claim 16, wherein the second block of the block copolymer includes a crosslinked structure.

18. A method of forming a polymer film, the method comprising: forming a polymer film that includes the block copolymer of claim 1 on a substrate, wherein the block copolymer is self-assembled.

19. The method of claim 18, further comprising: crosslinking of the second block of the block copolymer, wherein the block copolymer is self-assembled.

20. A method of forming a pattern, the method comprising: selectively removing any one block of the block copolymer of claim 1 from a laminate that is made up of a substrate and a polymer film, which is formed on the substrate and includes the block copolymer, wherein the block copolymer is self-assembled.

21. The polymer film of claim 20, wherein the second block of the block copolymer includes a crosslinked structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0122] FIG. 1 is a SEM image of a polymer layer that is formed by using a block copolymer of Example 1 and that is before a photo crosslinking.

[0123] FIG. 2 is a SEM image of a polymer layer that is formed by using a block copolymer of Example 1 and that is after a photo crosslinking.

[0124] FIG. 3 shows a result after subjecting a polymer layer formed by using a block copolymer of Example 1 to a solvent washing without a photo crosslinking.

EFFECT

[0125] The present application can provide a block copolymer and uses thereof. The block copolymer of the present application exhibits an excellent self-assembling property or phase separation property, can be provided with a variety of required functions without constraint and, especially, etching selectivity can be secured, making the block copolymer effectively applicable to such uses as pattern formation.

DETAILED DESCRIPTION OF EMBODIMENTS

[0126] The present application is described in more detail hereinafter through examples according to the present application, but the scope of the present application is not limited to the examples which are proposed hereinafter.

[0127] 1. NMR Measurement

[0128] NMR analysis was carried out at room temperature by using a NMR spectrometer that includes a Varian Unity Inova (500 MHz) spectrometer with a 5-mm triple resonance probe. The analysis subject material was diluted with a solvent (CDCl.sub.3) for an NMR measurement to a concentration of about 10 mg/ml for use, and the chemical shift was expressed in ppm.

[0129] <Applied Abbreviations>

[0130] br=broad signal, s=singlet, d=doublet, dd=doublet of doublets, t=triplet, dt=doublet of triplets, q=quartet, p=quintet, m=multiplet.

[0131] 2. Gel Permeation Chromatography (GPC)

[0132] The number average molecular weight (Mn) and molecular weight distribution were measured by GPC. The analysis subject material such as a macroinitiator or the block copolymer of the examples was put in a 5-mL vial and diluted with tetrahydrofuran (THF) to a concentration of about 1 mg/mL. Then, a standard specimen for calibration and the specimen to be analyzed were filtered with a syringe filter (pore size: 0.45 μm) and subsequently analyzed. ChemStation (Agilent Technologies Inc.) was used as the analytical program, each of the weight average molecular weight (Mw) and Mn was obtained by comparing the elution time of the specimen with the calibration curve, and then a molecular weight distribution (polydispersity index, PDI) was calculated as a ratio (Mw/Mn). The measuring condition of GPC is as follows:

[0133] <GPC Measuring Conditions>

[0134] Device: 1200 Series of Agilent Technologies Inc.

[0135] Column: Two PLgel MIXED-B of Polymer Laboratories

[0136] Solvent: THF

[0137] Column temperature: 35° C.

[0138] Sample concentration: 1 mg/mL, 200 L is injected

[0139] Standard specimen: polystyrene (Mp: 3900000, 723000, 316500, 52200, 31400, 7200, 3940, 485)

Preparation Example 1

[0140] The compound (DPM-C12) represented by the following Structural Formula A was synthesized by the following method: hydroquinone (10.0 g, 94.2 mmol) and 1-bromododecane (23.5 g, 94.2 mmol) were introduced into a 250-mL flask, dissolved in 100 mL of acetonitrile; then, an excessive amount of potassium carbonate was added to the above solution and allowed to react at about 75° C. for about 48 hours under a nitrogen atmosphere; upon completion of the reaction, the reaction products were removed of the remaining potassium carbonate and of acetonitrile that was used for the reaction; then the substances were worked up through an addition of a mixed solvent of dichloromethane (DCM) and water, and the separated organic layer was dehydrated with MgSO.sub.4; subsequently, the substances were purified by column chromatography (CC) with DCM to obtain a white solid intermediate with a yield of about 37%.

[0141] <NMR Analysis Results of Intermediate>

[0142] .sup.1H-NMR (CDCl.sub.3): δ6.77 (dd, 4H); δ4.45 (s, 1H); δ3.89 (t, 2H); δ1.75 (p, 2H); δ1.43 (p, 2H); δ1.33-1.26 (m, 16H); δ0.88 (t, 3H).

[0143] The synthesized intermediate (9.8 g, 35.2 mmol), methacrylic acid (6.0 g, 69.7 mmol), dicyclohexylcarbodiimide (DCC) (10.8 g, 52.3 mmol) and p-dimethylaminopyridine (DMAP) (1.7 g, 13.9 mmol) were introduced into a flask, 120 mL of methylene chloride was added, and then allowed to react at room temperature for 24 hours under a nitrogen atmosphere; upon completion of the reaction, the reaction products were filtered to be removed of a urea salt that was produced during the reaction and also of the remaining methylene chloride; then, the substances were removed of impurities by column chromatography (CC) that uses hexane and dichloromethane (DCM) as the mobile phase, the obtained products were recrystallized in a mixed solvent of methanol and water (mixed at a weight ratio of 1:1) to obtain a white solid target material (DPM-C12) (7.7 g, 22.2 mmol) with a yield of 63%.

[0144] <NMR Analysis Results of DPM-C12>

[0145] .sup.1H-NMR (CDCl.sub.3): δ7.02 (dd, 2H); δ6.89 (dd, 2H); δ6.32 (dt, 1H); δ5.73 (dt, 1H); δ3.94 (t, 2H); δ2.05 (dd, 3H); δ1.76 (p, 2H); δ1.43 (p, 2H); 1.34-1.27 (m, 16H); δ0.88 (t, 3H).

##STR00008##

[0146] In Structural Formula A, R represents a linear-chain alkyl group with 12 carbons.

Preparation Example 2

[0147] 3-hydroxy-1,2,4,5-tetrafluorostyrene was synthesized by the following method. Pentafluorostyrene (25 g, 129 mmol) was added to a mixed solution of 400 mL of tert-butanol and potassium hydroxide (37.5 g, 161 mmol) and then reacted for 2 hours (reflux reaction). After cooling the reacted product to room temperature, 1200 mL of water was added thereto and remained butanol used for the reaction was eliminated via volatilization. The reacted product was extracted 3 times by diethyl ether (300 mL); the target materials were precipitated by acidifying the aqueous solution layer with a 10-weight % hydrochloric acid solution to a pH of about 3; and then the organic layer was collected by extracting 3 times by diethyl ether (300 mL).

[0148] The organic layer was then dehydrated with MgSO.sub.4 and solvent was removed so as to obtain crude product. The crude product was purified by column chromatography by using hexane and dichloromethane (DCM) as the mobile phase to acquire colorless liquid 3-hydroxy-1,2,4,5-tetrafluorostyrene (11.4 g). The results of NMR analysis on the above substance are as follows.

[0149] <NMR Analysis Results>

[0150] .sup.1H-NMR (DMSO-d): δ11.7 (s, 1H); δ6.60 (dd, 1H); δ5.89 (d, 1H); δ5.62 (d, 1H)

[0151] The compound of the chemical formula B below was synthesized by the following method. The obtained intermediate (3-hydroxy-1,2,4,5-tetrafluorostyrene) (1.7 g, 7.8 mmol), 4-benzoylbenzoic acid (1.9 g, 8.6 mmol), DCC (dicyclohexylcarbodiimide) (1.8 g, 8.6 mmol) and DMPA (p-dimethylaminopyridine) (0.48 g, 3.1 mmol) were mixed and 30 mL of methylene chloride was added thereto and then the mixture was reacted under nitrogen at room temperature for 24 hours. After the termination of the reaction, urea salt produced during the reaction and remained methylene chloride were eliminated. Impurities were eliminated in a column chromatography using hexane and DCM (dichloromethane) as a mobile phase and then the obtained product was recrystallized in mixed solvent of methanol and water (methanol:water=3:1 (weight ratio)) so as to obtain white solid target material that was the monomer of the chemical formula B with a yield of 70 weight %.

[0152] The results of NMR analysis on the above compound is as follows.

[0153] <NMR Analysis Results>

[0154] .sup.1H-NMR (CDCl.sub.3): δ8.3 (t, 2H); δ7.9 (q, 2H); δ7.8 (d, 2H); δ7.6 (t, 2H); δ7.5 (dd, 2H); δ6.60 (dd, 1H); δ5.89 (d, 1H); δ5.62 (d, 1H);

##STR00009##

Example 1

[0155] 2.0 g of the compound (DPM-C12) of Preparation Example 1, 64 mg of a reversible addition-fragmentation chain transfer (RAFT) reagent (2-cyano-2-propyl dodecyl trihiobenzoate), 23 mg of AIBN (azobisisobutyronitrile) and 5.34 mL of anisole were put into a 10 mL Schlenk flask, and stirred at room temperature for 30 minutes under a nitrogen atmosphere to allow an RAFT polymerization reaction at 70° C. for 4 hours. After the polymerization, a reaction solution was precipitated in 250 ml of methanol as an extraction solvent, and dried through decreased pressure filtration, thereby preparing a primrose macroinitiator. The yield of the macroinitiator was about 80 weight %, and the number average molecular weight (Mn) and distribution of molecular weight (Mw/Mn) of the macroinitiator were 6100 and 1.25, respectively.

[0156] 0.2 g of the obtained macroinitiator, 3.589 g of pentafluorostyrene and 0.151 g of the photo crosslinkable monomer of the structural formula B of Preparation Example 2 and 1.697 mL of anisole were put into a 10 mL Schlenk flask, and stirred at room temperature for 30 minutes under a nitrogen atmosphere to allow an RAFT polymerization reaction at 70° C. for 3 hours. After the polymerization, a reaction solution was precipitated in 250 ml of methanol as an extraction solvent, and dried through decreased pressure filtration, thereby preparing a light yellow block copolymer. The yield of the block copolymer was about 14 weight %, and the number average molecular weight (Mn) and distribution of molecular weight (Mw/Mn) of the block copolymer were 14,400 and 1.21, respectively. The block copolymer includes a first block derived from the compound (DPM-C12) of Preparation Example 1 and a second block derived from the pentafluorostyrene and the compound of the structural formula B in Preparation Example 2.

Test Example 1

[0157] A self-assembled polymer film was formed by using the block copolymer that was synthesized in Example 1, and the results were observed. The prepared block copolymer was dissolved in a solvent to a concentration of 1.0 weight %; then spin-coated on a silicon wafer for about 60 seconds at a speed of about 3000 rpm and then was subjected to a thermal annealing so as to form a polymer thin film including self assembled block copolymer. FIG. 1 is a SEM image of the obtained polymer thin film. Then the polymer thin film was irradiated with ultraviolet ray. The ultraviolet ray having a wavelength of about 254 nm was irradiated with light intensity of about 2 J/cm.sup.2. FIG. 2 is a SEM image of the polymer thin film after the above photocrosslinking. As a result of performing solvent washing to the polymer thin film, it was confirmed that the selective etching can be performed.

[0158] FIG. 3 shows the result after performing the solvent washing with respect to a polymer thin film before photo crosslinking process and it can be confirmed from FIG. 3 that the etching selectivity between blocks cannot be obtained.