Polymer composition

Abstract

Methods for forming a laminate are provided. The method provides a highly aligned block copolymer without orientation defects, coordination number defects distance defects and the like on a substrate, thereby providing a laminate which can be effectively applied to the production of various patterned substrates, and a method for producing a patterned substrate using the same.

Claims

1. A polymer composition comprising: a block copolymer which comprises a polymer segment A containing a first monomer unit and a polymer segment B having an absolute value of a surface energy difference with the polymer segment A of 10 mN/m or less and the polymer segment B containing a second monomer unit; and a random copolymer containing the first monomer unit and the second monomer unit, wherein the second monomer unit in the random copolymer has a volume fraction of 0.3 to 0.7 , and a sum of volume fractions of the first monomer unit and the second monomer unit in the random copolymer is 1, wherein the random copolymer is contained in a ratio of 1 vol % to 50 vol % based on a total volume of the block copolymer and the random copolymer, and wherein the first monomer unit is a unit represented by formula 1 below: ##STR00006## wherein, R is hydrogen or an alkyl group having 1 to 4 carbon atoms, X is a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, a carbonyl group, an alkylene group, an alkenylene group, —C(═O)—X.sub.1— or —X.sub.1—C(═O)—, where X.sub.1 is an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group or an alkynylene group, and Y is a monovalent substituent comprising a ring structure to which a side chain having 8 or more chain-forming atoms is linked, wherein the second monomer unit is a unit represented by formula 2 below: ##STR00007## wherein, R is hydrogen or an alkyl group having 1 to 4 carbon atoms, X.sub.2 is a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group, —C(═O)—X.sub.1— or —X.sub.1—C(═O)—, where X.sub.1 is a single bond, an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group or an alkynylene group, and W is an aryl group containing at least one halogen atom.

2. The polymer composition according to claim 1, wherein the polymer segment A satisfies at least one of the following conditions 1 to 3: condition 1: the polymer segment A exhibits a melting transition peak or an isotropic transition peak in a range of −80° C. to 200° C. in a DSC analysis: condition 2: the polymer segment A exhibits a peak having a half-value width in a range of 0.2 nm.sup.−1 to 0.9 nm.sup.−1 within a scattering vector (q) range of 0.5 nm.sup.−1 to 10 nm.sup.−1 in an XRD analysis: condition 3: the polymer segment A comprises a side chain, wherein a number (n) of chain-forming atoms in the side chain satisfies Equation 1 below with the scattering vector (q) in the XRD analysis:
3 nm.sup.−1≤nq/(2×π)≤5 nm.sup.−1   [Equation 1] wherein, n is the number of the chain-forming atoms and q is the smallest scattering vector (q) in which the peak is observed in the XRD analysis for the block copolymer or the scattering vector (q) in which the peak of the largest peak area is observed.

3. The polymer composition according to claim 1, wherein the polymer segment A in the block copolymer has a volume fraction of 0.3 to 0.7, and a sum of volume fractions of the polymer segment A and the polymer segment B is 1.

4. The polymer composition according to claim 1, wherein the block copolymer has a number average molecular weight in a range of 5,000 to 100,000.

5. The polymer composition according to claim 1, wherein the block copolymer has polydispersity in a range of 1.01 to 1.60.

6. The polymer composition according to claim 1, wherein the random copolymer has a number average molecular weight in a range of 5,000 to 100,000.

7. The polymer composition according to claim 1, wherein the random copolymer has polydispersity in a range of 1.01 to 1.80.

8. A laminate comprising: a substrate; a polymer membrane formed on a surface of the substrate, wherein the polymer membrane comprises a block copolymer which comprises a polymer segment A containing a first monomer unit and a polymer segment B having an absolute value of a surface energy difference with the polymer segment A of 10 mN/m or less and the polymer segment B containing a second monomer unit; and a random copolymer containing the first monomer unit and the second monomer unit, and the second monomer unit in the random copolymer has a volume fraction of 0.3 to 0.7 , and a sum of volume fractions of the first monomer unit and the second monomer unit in the random copolymer is 1, wherein the random copolymer is contained in a ratio of 1 vol % to 50 vol % based on a total volume of the block copolymer and the random copolymer, and wherein the first monomer unit is a unit represented by formula 1 below: ##STR00008## wherein, R is hydrogen or an alkyl group having 1 to 4 carbon atoms, X is a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, a carbonyl group, an alkylene group, an alkenylene group, —C(═O)—X.sub.1—or —X.sub.1—C(═O)—, where X.sub.1 is an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group or an alkynylene group, and Y is a monovalent substituent comprising a ring structure to which a side chain having 8 or more chain-forming atoms is linked, wherein the second monomer unit is a unit represented by formula 2 below: ##STR00009## wherein, R is hydrogen or an alkyl group having 1 to 4 carbon atoms, X.sub.2 is a single bond, an oxygen atom, a sulfur atom, —S(═O).sub.2—, an alkylene group, an alkenylene group, —C(═O)—X.sub.1— or —X.sub.1—C(═O)—, where X.sub.1 is a single bond, an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group or an alkynylene group, and W is an aryl group containing at least one halogen atom.

9. The laminate according to claim 8, wherein the block copolymer forms a lamellar structure.

10. The laminate according to claim 9, wherein the polymer membrane has a thickness of 1 L to 10 L, where L is a pitch of the lamellar structure.

11. A method for producing a patterned substrate, comprising: coating the polymer composition of claim 1 on a substrate; and annealing the polymer composition to form a self-assembled structure of the block copolymer.

12. The method according to claim 11, wherein a neutral layer is not present on the surface of the substrate on which the polymer composition is coated.

13. The method according to claim 12, further comprising: selectively removing one of the polymer segments of the block copolymer forming the self-assembled structure.

14. The method according to claim 13, further comprising: etching the substrate using the block copolymer from which one of the polymer segments has been removed as a mask.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows the GIWAXS analysis results of the monomer (A) synthesized in Preparation Example 1.

(2) FIG. 2 is an SEM photograph of the polymer membrane prepared in Example 1.

(3) FIG. 3 is a SEM photograph of the polymer membrane prepared in Example 2.

(4) FIG. 4 is a SEM photograph of the polymer membrane prepared in Example 3.

(5) FIG. 5 is a SEM photograph of the polymer membrane prepared in Example 4.

(6) FIG. 6 is a SEM photograph of the polymer membrane prepared in Example 5.

(7) FIG. 7 is an SEM photograph of the polymer membrane prepared in Comparative Example 1.

(8) FIG. 8 is an SEM photograph of the polymer membrane prepared in Comparative Example 2.

(9) FIG. 9 is a SEM photograph of the polymer membrane prepared in Comparative Example 3.

(10) FIG. 10 is an SEM photograph of the polymer membrane prepared in Comparative Example 4.

MODE FOR INVENTION

(11) Hereinafter, the present application will be described in detail by way of examples and comparative examples, but the scope of the present application is not limited by the following examples.

(12) 1. NMR Measurement

(13) NMR analyses were performed at room temperature using an NMR spectrometer including a Varian Unity Inova (500 MHz) spectrometer with a triple resonance 5 mm probe. An analyte was diluted in a solvent for NMR measurement (CDCl.sub.3) to a concentration of about 10 mg/ml, and chemical shifts were expressed in ppm.

(14) <Application Abbreviation>

(15) br=broad signal, s=singlet, d=doublet, dd=double doublet, t=triplet, dt=double triplet, q=quartet, p=quintet, m=multiplet.

(16) 2. GPC (Gel Permeation Chromatograph)

(17) The number average molecular weight (Mn) and the molecular weight distribution were measured using GPC (gel permeation chromatography) according to the following procedure.

(18) (1) Into a 5 mL vial, an analyte such as block copolymers of Examples or Comparative Examples or a macro initiator is put and diluted in THF (tetrahydrofuran) to be a concentration of about 1 mg/mL or so.

(19) (2) A standard sample for calibration and a sample to be analyzed are filtered through a syringe filter (pore size: 0.45 μm).

(20) (3) The GPC analysis is performed after injecting the filtered standard sample and analytical sample into the GPC apparatus.

(21) As the analytical program, ChemStation from Agilent Technologies was used, and the elution time of the sample was compared with the calibration curve to obtain the weight average molecular weight (Mw) and the number average molecular weight (Mn), respectively, and the molecular weight distribution (PDI) was calculated by the ratio (Mw/Mn) thereof. The measurement conditions of GPC are as follows.

(22) <GPC Measurement Conditions>

(23) Instrument: 1200 series from Agilent Technologies

(24) Column: using PLgel mixed B from Polymer laboratories

(25) Solvent: THF

(26) Column temperature: 35° C.

(27) Sample concentration: 1 mg/mL, 200 μL injection

(28) Standard samples: Polystyrene (Mp: 3900000, 723000, 316500, 52200, 31400, 7200, 3940, 485)

(29) 3. GISAXS (Grazing Incidence Small Angle X-Ray Scattering)

(30) The grazing incidence small angle X-ray scattering (GISAXS) analysis was performed using a Pohang accelerator 3C beamline according to the following procedure.

(31) (1) The block copolymer to be analyzed is diluted in fluorobenzene to a solid concentration of about 0.7 wt % to prepare a coating liquid.

(32) (2) The coating liquid is spin-coated on a base material to a thickness of about 5 nm. At this time, the coating area is adjusted to 2.25 cm.sup.2 or so (width: 1.5 cm, height: 1.5 cm).

(33) (3) After the coating, it is dried at room temperature for about 1 hour.

(34) (4) The dried collating liquid is subjected to thermal annealing again at about 160° C. for about 1 hour to form a polymer membrane in which the phase separation structure of the block copolymer to be analyzed is induced.

(35) (5) After an X-ray is incident on the formed polymer membrane at an incident angle in a range of about 0.12 degrees to 0.23 degrees corresponding to the angle between the critical angle of the membrane and the critical angle of the base material, an X-ray diffraction pattern, which is scattered from the membrane to a detector (2D marCCD) and exited, is obtained. At this time, when the distance from the membrane to the detector was within a range of about 2 m to 3 m, it was confirmed that the self-assembly pattern formed on the membrane was well observed.

(36) As the base material, a base material having a hydrophilic surface (a silicon substrate treated with a piranha solution and having a room temperature wetting angle of about 5 degrees to pure water) or a base material having a hydrophobic surface (a silicon substrate treated with HMDS (hexamethyldisilazane) and having a room temperature wetting angle of about 60 degrees to pure water) was used.

(37) 4. XRD Analysis

(38) The XRD analysis was performed by transmitting X rays to a sample at a Pohang accelerator 4C beamline to measure the scattering intensity according to the scattering vector (q). As the sample, a polymer in a powder state dried by purifying a synthesized polymer without special pretreatment and then maintaining it in a vacuum oven for one day or so, was placed in a cell for XRD measurement and used. Upon the XRD pattern analysis, an X-ray with a vertical size of 0.023 mm and a horizontal size of 0.3 mm was used and a 2D marCCD was used as a detector. A 2D diffraction pattern scattered and exited was obtained as an image. The obtained diffraction pattern was analyzed by a numerical analytical method to which a least-square method was applied to obtain information such as a scattering vector and a half-value width. Upon the analysis, an origin program was applied, and the profile of the XRD patterns was subjected to Gaussian fitting in a state where a portion showing the smallest intensity in the XRD diffraction patterns was taken as a baseline and the intensity in the above was set to zero, and then the scattering vector and the half-value width were obtained from the fitted results. The R square was set to be at least 0.96 or more upon Gaussian fitting.

(39) 5. Measurement of Surface Energy

(40) The surface energy was measured using a drop shape analyzer (DSA100 product from KRUSS) according to the following procedure.

(41) (1) A coating liquid is prepared by diluting the substance (polymer), which is measured, in fluorobenzene to a solid concentration of about 2 wt %.

(42) (2) The prepared coating liquid is spin-coated on a silicon wafer to a thickness of about 50 nm and a coating area of 4 cm.sup.2 (width: 2 cm, height: 2 cm) to form a coating layer.

(43) (3) The coating layer was dried at room temperature for about 1 hour and then subjected to thermal annealing at about 160° C. for about 1 hour.

(44) (4-1) The process of dropping the deionized water whose surface tension is known on the membrane after the thermal annealing and obtaining the contact angle thereof is repeated five times to obtain an average value of the obtained five contact angle values.

(45) (4-2) In the same manner, the process of dropping the diiodomethane whose surface tension is known on the membrane after the thermal annealing and obtaining the contact angle thereof is repeated five times to obtain an average value of the obtained five contact angle values.

(46) (5) The surface energy is obtained by substituting the value (Strom value) regarding the solvent surface tension by the Owens-Wendt-Rabel-Kaelble method using the average values of the contact angles for the deionized water and diiodomethane obtained in Steps (4-1) and (4-2) above.

(47) The numerical value of the surface energy for each polymer segment of the block copolymer was obtained for a homopolymer made of only the monomer forming the polymer segment by the above-described method.

(48) 6. GIWAXS (Grazing Incidence Wide Angle X-Ray Scattering)

(49) The grazing incidence wide angle X-ray scattering (GIWAXS) analysis was performed using a Pohang accelerator 3C beamline according to the following procedure.

(50) (1) The block copolymer to be analyzed is diluted in toluene to a solid concentration of about 1 wt % to prepare a coating liquid.

(51) (2) The coating liquid was spin-coated on the substrate to a thickness of about 30 nm. At this time, the coating area is adjusted to about 2.25 cm.sup.2 (width: 1.5 cm, height: 1.5 cm).

(52) (3) The coated coating solution was dried at room temperature for about 1 hour, and then subjected to thermal annealing at a temperature of about 160° C. for about 1 hour to form a polymer membrane.

(53) (4) After an X-ray is incident on the membrane at an incident angle in a range of about 0.12 degrees to 0.23 degrees corresponding to the angle between the critical angle of the membrane and the critical angle of the base material, an X-ray diffraction pattern, which is scattered from the membrane to a detector (2D marCCD) and exited, is obtained. At this time, it was confirmed that the crystal or liquid crystal structure formed on the membrane was well observed when the distance from the membrane to the detector was within the range of about 0.1 m to 0.5 m.

(54) As the base material, a base material having a hydrophilic surface (a silicon substrate treated with a piranha solution and having a room temperature wetting angle of about 5 degrees to pure water) was used.

(55) (5) In the GIWAXS spectrum, the scattering intensity in the azimuthal angle range of −90 degrees to 90 degrees of the diffraction pattern in the range of 12 nm.sup.−1 to 16 nm.sup.−1 (azimuthal angle when the upward direction of the diffraction pattern (out-of-plane diffraction pattern) is set as 0 degrees) is plotted, and the half-value width is obtained from the graph through Gauss fitting. At this time, when half of the peak was observed upon Gauss fitting, twice the value of the obtained half-value width (FWHM) was defined as the half-value width of the peak.

(56) 7. DSC Analysis

(57) The DSC analysis was performed using PerkinElmer DSC800 equipment according to the following procedure.

(58) (1) The sample to be analyzed is heated at a rate of 10° C. per minute from 25° C. to 200° C. under nitrogen atmosphere using the above equipment.

(59) (2) Subsequently, the sample to be analyzed is cooled from 200° C. to −80° C. at a rate of −10° C. per minute.

(60) (3) The sample to be analyzed is again raised from −80° C. to 200° C. at a rate of 10° C. per minute.

(61) (4) An endothermic curve according to the above procedure is obtained.

(62) (5) At this time, the obtained endothermic curve is analyzed to obtain a temperature (melting transition temperature, Tm) indicating a melting transition peak or a temperature (isotropic transition temperature, Ti) indicating an isotropic transition peak, and the area of the peak is obtained.

(63) Here, the temperature was defined as the temperature corresponding to the apex of each peak. Furthermore, the area per unit mass of each peak was defined as the value obtained by dividing the area of each peak by the mass of the sample, and this calculation was calculated using the program provided by the DSC equipment.

(64) 8. Analysis of Volume Fraction

(65) The volume fractions of a block copolymer and a random copolymer were calculated based on the NMR measurement results. Specifically, the volume fractions of the block copolymer and the random copolymer were calculated using Equation 3 below.
Volume fraction X=1/{1+(D×M)/(K×L)}  [Equation 3]

(66) The variables D, M, K and L applied to Equation 3 can be obtained by the following methods, respectively.

(67) D can be obtained by placing a sample to be analyzed (a homopolymer made only of the monomer forming the first block or a homopolymer made only of the monomer forming the second block) in ethanol (a solvent in which the mass and density in air are known), obtaining the density of each block through the mass, and calculating their ratios.

(68) Also, M can be obtained by the molecular weight of the monomer forming each block of the block copolymer.

(69) Furthermore, L can be obtained by the ratio of the number of hydrogen atoms of the monomer forming each block of the block copolymer, and for example, can be obtained from the structural formula of the monomer constituting each block copolymer.

(70) Finally, K can be calculated through the area of the spectrum obtained by the NMR measurement method as described above. At this time, in this case, when the peaks derived from the respective blocks of the block copolymer do not overlap, the area of the peak derived from each block is obtained, and K can be obtained through the ratio.

(71) However, when there is a portion where peaks derived from each block of the block copolymer overlap, the K should be obtained in consideration of this. In this case, a method of obtaining the K value in consideration of the superposition or the like is known, and for example, it can be obtained by applying an NMR analysis program such as a MestReC program, or the like.

Preparation Example 1. Synthesis of monomer (A)

(72) A monomer (DPM-C12) of Formula A below was synthesized in the following manner.

(73) (1) Hydroquinone (10.0 g, 94.2 mmol) and 1-bromododecane (23.5 g, 94.2 mmol) are placed in a 250 mL flask, dissolved in 100 mL of acetonitrile, and then an excess amount of potassium carbonate is added thereto and reacted at 75° C. for about 48 hours under a nitrogen condition.

(74) (2) After the reaction, the remaining potassium carbonate is filtered off and the acetonitrile used in the reaction is also removed.

(75) (3) A mixed solvent of DCM (dichloromethane) and water is added thereto to work up the mixture, and the separated organic layers are collected and passed through MgSO.sub.4 to be dehydrated.

(76) (4) Subsequently, the target product (4-dodecyloxyphenol) (9.8 g, 35.2 mmol) in a white solid phase is obtained using dichloromethane in column chromatography. At this time, the yield of the obtained target product was about 37%.

(77) <NMR analysis results>

(78) .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).

(79) (5) The synthesized 4-docecyloxyphenol (9.8 g, 35.2 mmol), methacrylic acid (6.0 g, 69.7 mmol), DCC (dicyclohexylcarbodiimide) (10.8 g, 52.3 mmol) and DMAP (p-dimethylaminopyridine) (1.7 g, 13.9 mmol) are placed in the flask and 120 mL of methylene chloride is added thereto, and then reacted at room temperature for 24 hours under nitrogen.

(80) (6) After completion of the reaction, the salt (urea salt) produced during the reaction and methylene chloride are removed with a filter.

(81) (7) Impurities are removed using hexane and DCM (dichloromethane) as the mobile phase in column chromatography and the product obtained again is recrystallized in a mixed solvent of methanol and water (1:1 mix) to obtain the target product (7.7 g, 22.2 mmol) in a white solid phase. At this time, the yield of the obtained target product was about 63%.

(82) <NMR Analysis Results>

(83) .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).

(84) ##STR00005##

(85) In Formula A, R is a linear alkyl group having 12 carbon atoms.

(86) GIWAXS, XRD and DSC Analyses

(87) A homopolymer was prepared using the monomer (A) of Preparation Example 1, and GIWAXS and DSC were analyzed for the prepared homopolymer. Here, the homopolymer was prepared by a method of synthesizing a macromonomer using the monomer (A) in the following examples.

(88) FIG. 1 shows the results of GIWAXS analysis of the homopolymer. In FIG. 1, R square was about 0.264 upon Gauss fitting. As a result of the DSC analysis for the homopolymer, the corresponding polymer showed a melting temperature of about −3° C. and an isotropic transition temperature of about 15° C. Also, the ratio (M/I) of the area (M) of the melting transition peak to the area (I) of the isotropic transition peak in the DSC analysis of the homopolymer was about 3.67, the half-value width of the peak in an azimuthal angle of −90 degrees to 70 degrees of the diffraction pattern of the scattering vector in a range of 12 nm.sup.−1 to 16 nm.sup.−1 in GIWAXS was about 48 degrees, and the half-value width of the peak in an azimuthal angle of 70 degrees to 90 degrees of the diffraction pattern of the scattering vector in a range of 12 nm.sup.−1 to 16 nm.sup.−1 in GIWAXS was about 58 degrees. Furthermore, in the X-ray diffraction analysis (XRD), a peak having a half-value width of about 0.57 nm.sup.−1 or so was observed at a scattering vector value of 1.96 nm.sup.−1.

Preparation Example 2. Synthesis of Block Copolymer (B)

(89) The block copolymer (B) was synthesized in the following manner.

(90) (1) 2.0 g of the monomer (A) of Preparation Example 1, 64 mg of cyanoisoproyl dithiobenzoate as an RAFT (reversible addition-fragmentation chain transfer) reagent, 6 mg of AIBN (azobisisobutyronitrile) as a radical initiator and 5.34 mL of benzene are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(91) (2) An RAFT (reversible addition-fragmentation chain transfer) polymerization reaction is performed at 70° C. for 4 hours.

(92) (3) After the polymerization, the reaction solution is precipitated in 250 mL of methanol as an extraction solvent, and then filtered under reduced pressure and dried to prepare a pink macro initiator.

(93) At this time, the yield of the macro initiator was about 82.6 wt %, and the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) were 4,400 and 1.16, respectively.

(94) (4) 0.3 g of the macro initiator, 2.7174 g of a pentafluorostyrene monomer and 1.306 mL of benzene are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(95) (5) An RAFT (reversible addition-fragmentation chain transfer) polymerization reaction is performed at 115° C. for 6 hours.

(96) (6) After the polymerization, the reaction solution is precipitated in 250 mL of methanol, which is an extraction solvent, and then filtered and dried under reduced pressure to obtain a pale pink block copolymer (B). At this time, the yield of the block copolymer was about 18 wt %, and the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) were 14,400 and 1.12, respectively. The block copolymer comprised a polymer segment A, which was derived from the monomer (A) of Preparation Example 1 and had 12 chain-forming atoms (the number of carbon atoms of R in Formula A), and a polymer segment B derived from the pentafluorostyrene monomer. The volume fraction of the polymer segment A in the block copolymer was about 0.41 or so, and the volume fraction of the polymer segment B was about 0.59 or so. The surface energy and density of the polymer segment A of the block copolymer were 30.83 mN/m and 1 g/cm.sup.3, respectively, and the surface energy and density of the polymer segment B were 24.4 mN/m and 1.57 g/cm.sup.3, respectively. Also, the result calculated by substituting the number (12) of chain-forming atoms in the polymer segment A of the block copolymer and the scattering vector value (q) in which the peak having the largest peak area was identified in the scattering vector range of 0.5 nm.sup.−1 to 10 nm.sup.−1 upon the X-ray diffraction analysis into the equation nq/(2×π), respectively, was about 3.75.

Preparation Example 3. Synthesis of Block Copolymer (C)

(97) The block copolymer (C) was synthesized in the following manner.

(98) (1) 2.0 g of the monomer (A) of Preparation Example 1, 67 mg of cyanoisoproyl dithiobenzoate as an RAFT (reversible addition-fragmentation chain transfer) reagent, 7 mg of AIBN (azobisisobutyronitrile) as a radical initiator and 5.37 mL of anisole are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(99) (2) An RAFT (reversible addition-fragmentation chain transfer) polymerization reaction is performed at 70° C. for 4 hours.

(100) (3) After the polymerization, the reaction solution is precipitated in 250 mL of methanol as an extraction solvent, and then filtered under reduced pressure and dried to prepare a pink macro initiator.

(101) The yield of the macro initiator was about 81.3 wt %, and the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) were 9,100 and 1.17, respectively.

(102) (4) 0.3 g of the macro initiator, 2.74 g of a pentafluorostyrene monomer and 1.352 mL of anisole are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(103) (5) An RAFT (reversible addition-fragmentation chain transfer) polymerization reaction is performed at 115° C. for 4 hours.

(104) (6) After the polymerization, the reaction solution is precipitated in 250 mL of methanol, which is an extraction solvent, and then filtered and dried under reduced pressure to obtain a pale pink block copolymer (C). The yield of the block copolymer was about 17 wt %, and the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) were 24,500 and 1.12, respectively. The block copolymer comprised a polymer segment A, which was derived from the monomer (A) of Preparation Example 1 and had 12 chain-forming atoms (the number of carbon atoms of R in Formula A), and a polymer segment B derived from the pentafluorostyrene monomer. Here, the volume fraction of the polymer segment A was about 0.48 or so, and the volume fraction of the polymer segment B was about 0.52 or so. The surface energy and density of the polymer segment A of the block copolymer were 30.83 mN/m and 1 g/cm.sup.3, respectively, and the surface energy and density of the polymer segment B were 24.4 mN/m and 1.57 g/cm.sup.3, respectively. Also, the result calculated by substituting the number (12) of chain-forming atoms in the polymer segment A of the block copolymer and the scattering vector value (q) in which the peak having the largest peak area was identified in the scattering vector range of 0.5 nm.sup.−1 to 10 nm.sup.−1 upon the X-ray diffraction analysis into the equation nq/(2×π), respectively, was about 3.75.

Preparation Example 4. Synthesis of Random Copolymer (D)

(105) The random copolymer (D) was synthesized in the following manner.

(106) (1) 0.970 g of the monomer (A) of Preparation Example 1, 1.359 g of pentafluorostyrene, 6.6 mg of AIBN (azobisisobutyronitrile) as a radical initiator, 33.0 mg of an RAFT (reversible addition-fragmentation chain transfer) reagent (2-hydroxyethyl 2-(((dodecylthio)carbonothioyl)thio)-2-methylpropanoate), and 2.23 mL of anisole are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(107) (2) A radical polymerization reaction is performed at 70° C. for 12 hours.

(108) (3) After the polymerization, the reaction solution is precipitated in 250 mL of methanol as an extraction solvent, and then filtered under reduced pressure, and then dried to obtain a random copolymer.

(109) Here, the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) of the random copolymer were 17,100 and 1.28, respectively. Also, in the random copolymer, the volume fraction of the monomer unit of Preparation Example 1 was 0.50, and the volume fraction of the pentafluorostyrene unit was about 0.50.

Preparation Example 5. Synthesis of Random Copolymer (E)

(110) The random copolymer (E) was synthesized in the following manner.

(111) (1) 0.700 g of the monomer (A) of Preparation Example 1, 2.194 g of pentafluorostyrene, 6.6 mg of AIBN (azobisisobutyronitrile) as a radical initiator, 33.0 mg of an RAFT (reversible addition-fragmentation chain transfer) reagent (2-hydroxyethyl 2-(((dodecylthio)carbonothioyl)thio)-2-methylpropanoate), and 2.23 mL of anisole are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(112) (2) A radical polymerization reaction is performed at 70° C. for 12 hours.

(113) (3) After the polymerization, the reaction solution is precipitated in 250 mL of methanol as an extraction solvent, and then filtered under reduced pressure, and then dried to obtain a random copolymer.

(114) Here, the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) of the random copolymer were 12,700 and 1.16, respectively. Also, in the random copolymer, the volume fraction of the monomer unit of Preparation Example 1 was 0.37, and the volume fraction of the pentafluorostyrene unit was about 0.63.

Preparation Example 6. Synthesis of Random Copolymer (F)

(115) The random copolymer (F) was synthesized in the following manner.

(116) (1) 1.259 g of the monomer (A) of Preparation Example 1, 1.254 g of pentafluorostyrene, 6.6 mg of AIBN (azobisisobutyronitrile) as a radical initiator, 33.0 mg of an RAFT (reversible addition-fragmentation chain transfer) reagent (2-hydroxyethyl 2-(((dodecylthio)carbonothioyl)thio)-2-methylpropanoate), and 2.553 mL of anisole are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(117) (2) A radical polymerization reaction is performed at 70° C. for 12 hours.

(118) (3) After the polymerization, the reaction solution is precipitated in 250 mL of methanol as an extraction solvent, and then filtered under reduced pressure, and then dried to obtain a random copolymer.

(119) Here, the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) of the random copolymer were 12,400 and 1.17, respectively. Also, in the random copolymer, the volume fraction of the monomer unit of Preparation Example 1 was 0.65, and the volume fraction of the pentafluorostyrene unit was about 0.35.

Preparation Example 7. Synthesis of Random Copolymer (G)

(120) The random copolymer (G) was synthesized in the following manner.

(121) (1) 0.560 g of the monomer (A) of Preparation Example 1, 2.664 g of pentafluorostyrene, 6.6 mg of AIBN (azobisisobutyronitrile) as a radical initiator, 33.0 mg of an RAFT (reversible addition-fragmentation chain transfer) reagent (2-hydroxyethyl 2-(((dodecylthio)carbonothioyl)thio)-2-methylpropanoate), and 3.234 mL of anisole are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(122) (2) A radical polymerization reaction is performed at 70° C. for 12 hours.

(123) (3) After the polymerization, the reaction solution is precipitated in 250 mL of methanol as an extraction solvent, and then filtered under reduced pressure, and then dried to obtain a random copolymer.

(124) Here, the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) of the random copolymer were 12,000 and 1.18, respectively. Also, in the random copolymer, the volume fraction of the monomer unit of Preparation Example 1 was 0.29, and the volume fraction of the pentafluorostyrene unit was about 0.71.

Preparation Example 8. Synthesis of Random Copolymer (H)

(125) The random copolymer (H) was synthesized in the following manner.

(126) (1) 4.449 g of the monomer (A) of Preparation Example 1, 2.022 g of pentafluorostyrene, 6.6 mg of AIBN (azobisisobutyronitrile) as a radical initiator, 33.0 mg of an RAFT (reversible addition-fragmentation chain transfer) reagent (2-hydroxyethyl 2-(((dodecylthio)carbonothioyl)thio)-2-methylpropanoate), and 6.510 mL of anisole are placed in a 10 mL Schlenk flask and stirred at room temperature for 30 minutes under a nitrogen atmosphere.

(127) (2) A radical polymerization reaction is performed at 70° C. for 12 hours.

(128) (3) After the polymerization, the reaction solution is precipitated in 250 mL of methanol as an extraction solvent, and then filtered under reduced pressure, and then dried to obtain a random copolymer.

(129) Here, the number average molecular weight (Mn) and the molecular weight distribution (Mw/Mn) of the random copolymer were 23,400 and 1.34, respectively. Also, in the random copolymer, the volume fraction of the monomer unit of Preparation Example 1 was 0.73, and the volume fraction of the pentafluorostyrene unit was about 0.27.

Example 1

(130) A polymer composition was prepared by blending the block copolymer (B) of Preparation Example 2 and the random copolymer (D) of Preparation Example 4 on a silicon wafer substrate such that the volume fraction of the random copolymer of Preparation Example 4 was about 5 vol % relative to the total volume of the block copolymer and the random copolymer. A coating solution prepared by diluting the polymer composition to a solid content concentration of about 0.6 wt % in fluorobenzene was spin-coated on the substrate to a thickness of about 25 nm and dried at room temperature for about 1 hour. Subsequently, the coating liquid was subjected to thermal annealing at a temperature of about 180° C. for about 1 hour to form a polymer membrane. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 2. The block copolymer in the polymer membrane formed a vertically oriented lamellar phase, where the pitch thereof was about 11 nm or so. From FIG. 2, it can be confirmed that the block copolymer can form a highly aligned vertically oriented lamellar pattern in the polymer membrane produced by the polymer composition of the present application.

Example 2

(131) A polymer membrane was formed in the same manner as in Example 1, except that a polymer composition was prepared by blending the block copolymer (B) of Preparation Example 2 and the random copolymer (D) of Preparation Example 4 on a silicon wafer substrate such that the volume fraction of the random copolymer (D) of Preparation Example 4 was about 15 vol % relative to the total volume of the block copolymer and the random copolymer. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 3. The block copolymer in the polymer membrane formed a vertically oriented lamellar phase, where the pitch thereof was about 11 nm or so. From FIG. 3, it can be confirmed that the block copolymer can form a highly aligned vertically oriented lamellar pattern in the polymer membrane produced by the polymer composition of the present application.

Example 3

(132) A polymer composition was prepared by blending the block copolymer (C) of Preparation Example 3 and the random copolymer (D) of Preparation Example 4 on a silicon wafer substrate such that the volume fraction of the random copolymer of Preparation Example 4 was about 15 vol % relative to the total volume of the block copolymer and the random copolymer. A coating solution prepared by diluting the polymer composition to a solid content concentration of about 0.8 wt % in fluorobenzene was spin-coated on the substrate to a thickness of about 30 nm and dried at room temperature for about 1 hour. Subsequently, the coating liquid was subjected to thermal annealing at a temperature of about 230° C. for about 1 hour to form a polymer membrane. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 4.

(133) The block copolymer in the polymer membrane formed a vertically oriented lamellar phase, where the pitch thereof was about 17 nm or so. From FIG. 4, it can be confirmed that the block copolymer can form a highly aligned vertically oriented lamellar pattern in the polymer membrane produced by the polymer composition of the present application.

Example 4

(134) A polymer membrane was formed in the same manner as in Example 1, except that a polymer composition was prepared by blending the block copolymer (B) of Preparation Example 2 and the random copolymer (E) of Preparation Example 5 on a silicon wafer substrate such that the volume fraction of the random copolymer of Preparation Example 5 was about 10 vol % relative to the total volume of the block copolymer and the random copolymer. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 5. The block copolymer in the polymer membrane formed a vertically oriented lamellar phase, where the pitch thereof was about 11 nm or so. From FIG. 5, it can be confirmed that the block copolymer can form a highly aligned vertically oriented lamellar pattern in the polymer membrane produced by the polymer composition of the present application.

Example 5

(135) A polymer membrane was formed in the same manner as in Example 1, except that a polymer composition was prepared by blending the block copolymer (B) of Preparation Example 2 and the random copolymer (F) of Preparation Example 6 on a silicon wafer substrate such that the volume fraction of the random copolymer of Preparation Example 6 was about 10 vol % relative to the total volume of the block copolymer and the random copolymer. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 6. The block copolymer in the polymer membrane formed a vertically oriented lamellar phase, where the pitch thereof was about 11 nm or so. From FIG. 6, it can be confirmed that the block copolymer can form a highly aligned vertically oriented lamellar pattern in the polymer membrane produced by the polymer composition of the present application.

Comparative Example 1

(136) A polymer membrane was formed in the same manner as in Example 1, except that the polymer composition containing the block copolymer (B) of Preparation Example 2 alone was prepared without containing the random copolymer. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 7. From FIG. 7, it can be seen that in the polymer membrane of Comparative Example 1, more horizontal orientation defects are observed in the self-assembled structure formed by the block copolymer, as compared with the polymer membranes of Example 1 and Example 2.

Comparative Example 2

(137) A polymer membrane was formed in the same manner as in Example 3, except that the polymer composition containing the block copolymer (C) of Preparation Example 3 alone was prepared without containing the random copolymer. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 8. From FIG. 8, it can be seen that in the polymer membrane of Comparative Example 2, more horizontal orientation defects are observed in the self-assembled structure formed by the block copolymer, as compared with the polymer membrane of Example 3.

Comparative Example 3

(138) A polymer membrane was formed in the same manner as in Example 1, except that a polymer composition was prepared by blending the block copolymer (B) of Preparation Example 2 and the random copolymer (G) of Preparation Example 7 on a silicon wafer substrate such that the volume fraction of the random copolymer (G) of Preparation Example 7 was about 10 vol % relative to the total volume of the block copolymer and the random copolymer. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 9. According to FIG. 9, it can be confirmed that the block copolymer in the polymer membrane is not vertically oriented to the bottom of the substrate, and U-shaped defects exist in the polymer membrane.

Comparative Example 4

(139) A polymer membrane was formed in the same manner as in Example 1, except that a polymer composition was prepared by blending the block copolymer (B) of Preparation Example 2 and the random copolymer (H) of Preparation Example 8 on a silicon wafer substrate such that the volume fraction of the random copolymer (H) of Preparation Example 9 was about 10 vol % relative to the total volume of the block copolymer and the random copolymer. A scanning electron microscope (SEM) image of the polymer membrane was taken and shown in FIG. 10. According to FIG. 10, it can be confirmed that the block copolymer in the polymer membrane is not vertically oriented to the bottom of the substrate, and horizontal orientation defects exist in the polymer membrane.