KR101001161B1 - Method of forming a pattern array of ferroelectric pvdf thin film by using a polymer binder - Google Patents

Abstract

The present invention relates to a method of forming a pattern array of a ferroelectric polyvinylidene fluoride (PVDF) thin film using a polymer binder. Specifically, 1) PVDF polymer, and a polymer binder capable of UV curing with excellent compatibility with the PVDF polymer. Dissolving in a solvent and coating the mixture on a substrate to form a PVDF thin film; And 2) irradiating UV through the patterned mask on the coated thin film to induce UV curing only in the irradiated portion, and then removing the uncured portion by using a solvent to form a pattern array. A method of forming a patterned array of ferroelectric PVDF thin films using a polymeric binder, comprising the steps of:

PVDF, Ferroelectric Thin Film, Pattern Array, Curable Polymer Binder

Description

Method for forming pattern array of ferroelectric PDF thin film using polymer binder {METHOD OF FORMING A PATTERN ARRAY OF FERROELECTRIC PVDF THIN FILM BY USING A POLYMER BINDER}

The present invention relates to a method capable of precisely and mass forming a pattern array of a ferroelectric PVDF thin film using a polymer binder having excellent compatibility with a PVDF polymer and capable of UV curing.

Ferroelectric polymers such as polyvinylidene fluoride (hereinafter abbreviated as "PVDF") or P (VDF-TrFE), a copolymer of PVDF and trifluoroethylene (TrFE), are polymer specific. Due to its excellent processability and low manufacturing cost, applications have recently been attempted in various fields. For example, the application to non-volatile memory field (Korean Patent Publication No. 2007-76698) and piezoelectric power generation using piezoelectricity as an information storage device utilizing the inherent ferroelectric properties of PVDF. Research in the field of energy harvesting device (Rome et al., Science 309: 1725-1728, 2005), application in the field of tactile sensor (US Patent No. 5,760, 530) and the like are actively being researched.

PVDF polymer has a dipole formed between hydrogen and fluorine atoms and shows a big difference in its ferroelectric properties depending on the crystallization structure.The α-crystal structure has the most stable TGTG (Trans-Gauche-Trans-Gauche) structure. Does not exhibit ferroelectricity, while the β-crystal structure with TTTT structure shows the best ferroelectricity, and the γ-crystal structure with TTTG structure shows weak ferroelectricity than β-crystal structure. P (VDF-TrFE) copolymers always have a β-crystal structure and have excellent ferroelectric properties, but have a disadvantage in that manufacturing cost is high. In order to overcome this disadvantage, process conditions such as heat treatment temperature (Horibe et al . , J. Electrochem. Soc. 153: G119-G124, 2006), pressure (Scheinbeim et al. , J. Appl. Phys. 50: 4399, 1979) Research is underway to induce ferroelectricity by controlling the crystal structure of PVDF through change.

In addition, PVDF is characterized by showing bistable stability only when a very high electric field of 50 MV / m or more is applied, and has a problem that thinning is required to lower such applied voltage for practical industrial applications.

In addition, in order to apply PVDF polymer to high integration devices, a method of forming a pattern array of ferroelectric PVDF thin films is required. However, PVDF polymers are difficult to pattern because of their inherent chemical stability, which makes chemical modification very difficult. Recently, a method of forming a pattern array of PVDF thin films by applying physical pressure such as an imprint method has been proposed (Korean Patent Publication No. 2008-13053), but the pattern array manufactured by this method has a limitation of having a γ-crystal structure. see.

Accordingly, the present inventors have diligently researched to solve the problems of the prior art in which only the physical patterning such as the imprinting method was possible due to the characteristics of the PVDF polymer which is difficult to chemically modify due to its excellent chemical stability. The present invention was completed by confirming that the use of a polymer binder can form a pattern array of ferroelectric PVDF thin films in a sophisticated and large amount.

It is therefore an object of the present invention to provide a method capable of forming a sophisticated and large volume of patterned arrays of ferroelectric PVDF thin films by non-physical techniques to enable their application in highly integrated devices.

In order to achieve the above object, the present invention provides a method of forming a pattern array of ferroelectric PVDF thin film using a polymer binder excellent in compatibility with the PVDF polymer and capable of UV curing.

In the method of forming a patterned array of ferroelectric PVDF thin films according to the present invention, PVDF polymers have excellent chemical stability and are difficult to chemically modify. The invention overcomes the problems in forming a pattern array of thin films. The high-compatibility of PVDF polymers and the use of a UV-curable polymer binder make fine and bulk ferroelectric PVDF pattern arrays irrespective of the crystal structure of PVDF polymers. It can be formed to be very useful for applications in high-density devices.

The present invention relates to a method of forming a patterned array of ferroelectric PVDF thin films using a polymer binder.

Specifically, the method of forming a pattern array of the ferroelectric PVDF thin film according to the present invention,

1) dissolving a PVDF polymer, and a polymer binder having excellent compatibility with the UV curable polymer in a solvent and coating the mixture on a substrate to form a PVDF thin film; And

2) irradiating UV through the patterned mask on the coated thin film to induce UV curing only in the irradiated portion, and then remove the uncured portion using a solvent to form a pattern array by irradiating UV. It includes.

The method of forming a patterned array of ferroelectric PVDF thin film according to the present invention overcomes the problems of conventional physical patterning techniques such as microimprinting, and uses a polymer binder capable of UV curing while having excellent compatibility with PVDF. Characterized in that.

Hereinafter, a method of forming a pattern array of the ferroelectric PVDF thin film according to the present invention will be described in detail step by step.

Step 1) is a step of dissolving a PVDF polymer, and a polymer binder having excellent compatibility with UV curing in a solvent and coating the mixture on a substrate to form a PVDF thin film, the PVDF polymer and 100 parts by weight of the polymer 1 to 700 parts by weight of the polymer binder is dissolved in 300 to 20,000 parts by weight of a solvent to prepare a PVDF / polymer binder mixture, which is then coated on a substrate to form a PVDF thin film.

In step 1), the PVDF polymer includes a PVDF homopolymer or a ferroelectric PVDF polymer such as P (VDF-TrFE) which is a copolymer of PVDF and trifluoroethylene (TrFE).

In step 1), the polymer binder is a polymer having excellent compatibility with the ferroelectric PVDF polymer and capable of UV curing, and can be used without limiting the type thereof. In the present invention, "excellent" compatibility with the ferroelectric PVDF polymer means that the polymer binder has no phase separation with the PVDF polymer after coating or even if the phase separation domain is 100 nm or less.

The polymer binder suitable for the present invention is a PMMA-based polymer containing polymethylmethacrylate (PMMA) polymer having excellent compatibility with PVDF in a molar ratio of 50 to 99.9% in the main chain or the side chain and including a functional group capable of UV curing. . Representative examples of such a polymer binder is a polymer represented by the following formula (1).

Wherein Me is CH ₃ , Y is a UV curable functional group, and x means between 0.5 and 0.999.

UV-curable functional groups in the polymer binder include unsaturated double bond (C = C), azide (-N ₃ ) functional group, epoxide functional group, glycidyl functional group and the like.

The polymer binder of Formula 2 is a polymer containing an unsaturated double bond as a functional group capable of UV curing on the PMMA backbone.

Wherein Me is CH ₃ and x means between 0.5 and 0.999.

The polymer binder of Formula 3 is a polymer including an azide (-N ₃ ) functional group as a functional group capable of UV curing on the PMMA backbone.

Wherein Me is CH ₃ and x means between 0.5 and 0.999.

The polymer binder of Chemical Formula 3 is a polymer including glycidyl functional group as a functional group capable of UV curing on the PMMA backbone.

Wherein Me is CH ₃ and x means between 0.5 and 0.999.

The above-described PVDF polymer and polymer binder are added to a suitable solvent and dissolved to prepare a PVDF / polymer binder mixture for thin film formation. At this time, it is preferable to add a solvent so that the viscosity of the final mixture is in the range of 10 to 50,000 cps. More preferably, adjusting the viscosity to be 200 to 5,000 cps is more advantageous for controlling the thickness of the thin film without the pin hole of the thin film after coating. Such solvents include ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, diethylene glycol dimethylethyl ether, methyl methoxy propionate, in consideration of compatibility with PVDF polymers, binder resins and / or other additive compounds. Ethyl ethoxy propionate (EEP), ethyl lactate, propylene glycol methyl ether acetate (PGMEA), propylene glycol methyl ether, propylene glycol propyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol methyl acetate , Diethylene glycol ethyl acetate, acetone, methyl isobutyl ketone, cyclohexanone, dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP) , γ-butyrolactone, diethyl ether, ethylene glycol dimethyl ether, diglyme, tetrahydrofuran (THF), Solvent selected from allol, ethanol, propanol, iso-propanol, methyl cellosolve, ethyl cellosolve, diethylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol methyl ether, toluene, xylene, hexane, heptane and octane It can be used individually or in mixture of 1 or more types.

As a method of forming a ferroelectric PVDF thin film on a substrate using the PVDF / polymer binder mixture prepared as described above, a vacuum deposition method including a thermal evaporation method, spin coating, roll coating, Spray coating, printing, etc. may be mentioned, but it is not limited to this. In a preferred embodiment of the present invention, a PVDF thin film is prepared by spin coating the PVDF / polymer binder mixture onto a substrate. At this time, the thickness of the thin film is preferably in the range of 30 nm to 1 mm, the thickness of the thin film can be controlled by changing the viscosity of the PVDF / polymer binder mixture and the rotational speed during spin coating.

In addition, in step 1), the PVDF / polymer binder mixture for forming the ferroelectric PVDF thin film adds an additive such as a photoinitiator, a multifunctional monomer, a photoacid generator, etc. in addition to the polymeric binder to promote UV curing. It can be included as. Each of the additives may be used in an amount of 1 to 100 parts by weight based on 100 parts by weight of the polymer binder.

The photoinitiator is a conventional initiator that generates free radicals or cations by light, and may be used as long as it is a material that can be dissolved in the cosolvent of PVDF polymer and polymer binder. As a photoinitiator suitable for this invention, it is preferable to use acetophenone, benzophenone series, and a triazine system, such as Irgacure 369, Igacure 651, Igacure 907, TPO, CGI124, and EPD / BMS mixed system. For example, the benzophenone-based photoinitiator includes benzophenone, phenylbiphenyl ketone, 1-hydroxy-1-benzoylcyclohexane, benzyl, benzyldimethyl ketal, 1-benzyl-1-dimethylamino-1- (4 -Morpholino-benzoyl) propane, 2-morphoyl-2- (4-methylmercapto) benzoylpropane, thioxanthone, 1-chloro-4- hydroxythioxanthone, isopropyl thioxanthone, di Ethyl thioxanthone, ethyl anthraquinone, 4-benzoyl-4-methyldiphenylsulfide, benzoin butyl ether, 2-hydroxy-2-benzoylpropane, 2-hydroxy-2- (4-isopropyl) benzoylpropane , 4-butylbenzoyltrichloromethane, 4-phenoxybenzoyldichloromethane, methyl benzoyl formate, 1,7-bis (9-acridinyl) heptane, 9-n-butyl-3,6-bis (2- Morpholino-isobutyloyl) carbazole, and the like, and triazine photoinitiators include 2-methyl-4,6-bis (trichloromethyl) -s-triazine, 2-phenyl-4,6-bis (tri) Chloromethyl) -s-triazine, 2-naphthyl-4,6-bis (trichloromethyl) -s-triazine, 4,4-bis (diphenylsulfonio) -diphenylsulfide hexafluoroanti Monates (BDSDS), 4,4- (phenylthio) phenyldiphenylsulfonium hexafluoroandimonate (PTPDS), and the like, which may be used alone or in combination of two or more.

The multifunctional monomer is a monomer having two or more unsaturated double bonds, and can be used without limitation as long as it can be dissolved in the cosolvent of the PVDF polymer and the polymer binder. Examples of the multifunctional monomer suitable for the present invention include meta-divinylbenzene, para-divinylbenzene, 4,4'-divinylbiphenylene, 1,5-divinylnaphthalene, cyclohexanedimethanol diacrylate, and di Ethylene glycol diacrylate, triethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, vinyl acrylate, 1,2-ethanediol diacrylate, 1,3-propanediol diacrylate , 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, bisphenol A diacryl Latex, cyclohexane dimethanol dimethacrylate, bisphenol A dimethacrylate, methacrylated polybutadiene, triethylene glycol dimetharate Relate, ethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentylglycol dimethacrylate, urethane acrylate, and the like, which are alone Or in combination of two or more.

The photoacid generator may be used without limitation as long as it is ionic or nonionic and can be dissolved in the cosolvent of PVDF polymer and polymer binder. The photoacid generator absorbs light in the exposure process to generate an acid, and the generated acid acts as a catalyst in the crosslinking reaction by the crosslinking agent. Examples of photoacid generators suitable for the present invention include diazonium salts, iodonium salts, sulfonium salts, diazosulfonyl compounds, sulfonyloxyimides, nitrobenzylsulfonate esters, diphenyliodonium trifluoromethane sulfonates, Diphenyliodonium nonafluorobutane sulfonate, triphenylsulfonium trifluoromethane sulfonate, triazine, oxazole, oxadiazole, thiazole, phenolic sulfonic acid ester, bis-sulfonylmethane, bis- Sulfonylethane, bis-sulfonyldiazomethane, triphenylsulfonium tris (trifluoromethylsulfonyl) methide, diphenyliodonium bis (trifluoromethylsulfonyl) imide and their analogs do. The compounds may be used alone or in combination of two or more.

In step 2), the PVDF thin film prepared in step 1) is irradiated with UV through a patterned mask in a desired shape to induce the irradiated portion to crosslink, and then, using a solvent, the uncrosslinked portion is removed to form a pattern array. Forming. At this time, the UV irradiation is performed by irradiating UV at a wavelength of 100 to 700 nm for 1 to 10,000 seconds at an output of 10 to 10,000 mJ / cm 2. When UV is irradiated on the PVDF thin film through a mask as described above, since curing occurs only in the UV-irradiated portion, crosslinking is formed, the portion cured by UV irradiation by the subsequent solvent treatment is left and UV is not irradiated. By removing only the portions, a pattern array of a desired shape can be obtained.

In this step, the solvent used for removal of the uncured portion of the PVDF thin film uses the same solvent as that used for dissolving the PVDF polymer and the polymer binder in step 1).

As described above, the PVDF thin film on which the pattern array of the desired shape is formed may be further subjected to a heat treatment step in order to maximize the ferroelectricity by controlling the crystallization of the pattern array. The heat treatment is performed by heating the pattern array of the formed PVDF thin film to a temperature higher than the melting point of the PVDF crystal, performing heat treatment for 1 to 30 minutes, and then rapidly cooling the temperature below the normal temperature, and then raising the temperature to about 10 to 100 ° C. lower than the melting point. After the heat treatment for 1,000 minutes to may be carried out by the process of cooling to room temperature again.

As described above, the method of forming the pattern array of the ferroelectric PVDF thin film according to the present invention was only capable of physical patterning such as an imprint method due to the characteristics of the PVDF polymer, which is difficult to chemically modify due to its excellent chemical stability, and thus, fine patterning and bulk This invention overcomes the problems in the formation of the pattern array of PVDF thin film, which was impossible to pattern, and uses a high-compatibility and UV-curable polymer binder with PVDF polymer, and thus the ferroelectric PVDF pattern array regardless of the crystal structure of PVDF polymer. It can be formed very precisely and in a large amount, so it can be very useful for application in high density devices.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention more specifically, it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples in accordance with the gist of the present invention.

Example 1

1 g PVDF polymer, 0.2 g polymer binder of Formula 2, 0.01 g of 1,2-ethanediol diacrylate as a multifunctional monomer, and 0.01 g of igcure 148D as a photoinitiator in 20 ml of DMF to form PVDF / polymer A binder mixture was prepared. The prepared mixture was spin coated on an aluminum coated silicon wafer at a speed of 2,000 rpm to prepare a 200 nm thick PVDF thin film. A mask patterned into a desired shape was installed on the prepared PVDF thin film, and UV irradiation at a wavelength of 254 nm was performed at 500 mJ / cm 2 for 3 minutes to induce curing at the UV-irradiated portion. After UV irradiation, the uncrosslinked portion was dissolved and removed on the PVDF thin film using DMF to form a pattern array of the PVDF thin film (FIG. 1). The pattern array of the formed PVDF thin film was heated above the melting point of the PVDF crystal and heat-treated for 5 minutes, and then rapidly cooled to a temperature below normal temperature. Subsequently, the temperature was lowered to 50 ° C lower than the melting point of the PVDF crystals, and then heat-treated for 1 hour and then cooled to room temperature to maximize the ferroelectric properties of the PVDF thin film pattern array.

In order to investigate the ferroelectric properties of the PVDF thin film pattern array prepared as described above, residual polarization (P _r ) and constant voltage (Coercive field, E _c ) were measured, which are shown in Table 1 below. FIG. 2 is a result of observing a pattern array of the PVDF thin film prepared above under a microscope, and FIG. 3 shows a ferroelectric characteristic PE curve of the pattern array of the PVDF thin film.

Example 2

A patterned array of ferroelectric PVDF thin films was formed in the same manner as in Example 1 except that 0.2 g of the polymer binder of Chemical Formula 3 was used, and the ferroelectric characteristics thereof were investigated and shown in Table 1 below.

Example 3

0.2 g of the polymeric binder of Formula 4 and 4,4-bis (diphenylsulfonio) -diphenylsulfide hexafluoroantimonate (BDSDS) / 4,4- (phenylthio) phenyldiphenylsulfonium as a photoinitiator A patterned array of ferroelectric PVDF thin films was formed in the same manner as in Example 1 except that 0.01 g of hexafluoroandimonate (PTPDS) was used, and the ferroelectric properties thereof were investigated and shown in Table 1 below.

sample thickness P _r (mC / ㎡) E _c (MV / m) Example 1 200 47 45 Example 2 210 50 46 Example 3 230 52 44

As shown in Table 1 and Figure 3, the pattern array of the ferroelectric PVDF thin film prepared in accordance with the present invention has a residual polarization and a constant voltage level of 50 mC / ㎡ and 45 MV / m, respectively, and the conventional physical imprinting such as microimprinting It was confirmed that the ferroelectric properties were excellent compared to the pattern array manufactured by the method. From the above results, it can be seen that by using the polymer binder capable of UV curing while being compatible with the PVDF polymer according to the present invention, it is possible to form a pattern array of the PVDF thin film having excellent ferroelectricity in a sophisticated and large amount.

The specific parts of the present invention have been described in detail above, and for those skilled in the art, these specific descriptions are merely preferred embodiments, and the scope of the present invention is not limited thereto. Will be obvious. Thus, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

1 schematically illustrates a method of manufacturing a pattern array of PVDF thin films using a polymer binder according to the present invention,

2 is a result of observing the pattern array of the PVDF thin film prepared in Example 1 according to the present invention under a microscope,

Figure 3 shows the ferroelectric characteristics P-E curve of the pattern array of the PVDF thin film prepared in Example 1 according to the present invention.

Claims (20)

1) PVDF polymer, and Polymer binder containing polymethylmethacrylate (PMMA) polymer in the main chain or side chain in a molar ratio of 50 to 99.9% and including functional groups capable of UV curing Dissolving in a solvent and coating the mixture on a substrate to form a PVDF thin film; And 2) irradiating UV through the patterned mask on the coated thin film to induce UV curing only in the irradiated portion, and then remove the uncured portion using a solvent to form a pattern array by irradiating UV. A method of forming a patterned array of ferroelectric PVDF thin film using a polymeric binder, comprising. The method of claim 1, In step 1), 100 parts by weight of the PVDF polymer, and 1 to 700 parts by weight of the polymer binder is dissolved in 300 to 20,000 parts by weight of the solvent. The method of claim 1, And wherein the PVDF polymer in step 1) is a PVDF homopolymer or P (VDF-TrFE), a copolymer of PVDF and trifluoroethylene (TrFE). delete The method of claim 1, Method wherein the polymer binder is a polymer represented by the following formula (1): [Formula 1]

Wherein Me is CH ₃ , Y is a UV curable functional group and x is between 0.5 and 0.999. The method of claim 5, UV-curable functional group in the polymer binder is selected from the group consisting of unsaturated double bond (C = C), azide (-N ₃ ) functional group, epoxide functional group and glycidyl functional group. The method of claim 6, The polymer binder is a method characterized in that the polymer represented by the formula (2) comprising an unsaturated double bond as a functional group capable of UV curing on the PMMA backbone: [Formula 2]

Wherein Me is CH ₃ and x is between 0.5 and 0.999. The method of claim 6, Wherein the polymer binder is a polymer represented by the following Chemical Formula 3, including an azide (-N ₃ ) functional group as a functional group capable of UV curing on a PMMA backbone: (3)

Wherein Me is CH ₃ and x is between 0.5 and 0.999. The method of claim 6, Wherein the polymer binder is a polymer represented by the following formula (4) comprising a glycidyl functional group as a functional group capable of UV curing on the PMMA backbone: [Formula 4]

Wherein Me is CH ₃ and x is between 0.5 and 0.999. The method of claim 1, In step 1), the solvent is ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, diethylene glycol dimethylethyl ether, methyl methoxy propionate, ethyl ethoxy propionate (EEP), ethyl lactate, propylene glycol Methyl ether acetate (PGMEA), propylene glycol methyl ether, propylene glycol propyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol methyl acetate, diethylene glycol ethyl acetate, acetone, methyl isobutyl ketone, cyclohexa Paddy, dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), γ-butylolactone, diethyl ether, ethylene glycol dimethyl ether , Diglyme, tetrahydrofuran (THF), methanol, ethanol, propanol, iso-propanol, methylcellosolve, ethylcellosolve, A process selected from the group consisting of diethylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol methyl ether, toluene, xylene, hexane, heptane, octane and mixtures thereof. The method of claim 1, Wherein the mixture of PVDF polymer and polymer binder further comprises at least one of a photoinitiator, a multifunctional monomer and a photoacid generator as an additive. The method of claim 11, The additive is used in an amount of 1 to 100 parts by weight based on 100 parts by weight of PVDF polymer. The method of claim 11, The photoinitiator is Irgacure 369, Igacure 651, Igacure 907, TPO, CGI124, EPD / BMS mixed system, benzophenone, phenylbiphenyl ketone, 1-hydroxy-1-benzoylcyclohexane, benzyl, benzyl Dimethyl ketal, 1-benzyl-1-dimethylamino-1- (4-morpholino-benzoyl) propane, 2-morphoyl-2- (4-methylmercapto) benzoylpropane, thioxanthone, 1-chloro-4- hydroxy thioxanthone, isopropyl thioxanthone, diethyl thioxanthone, ethyl anthraquinone, 4-benzoyl-4-methyl diphenyl sulfide, benzoin butyl ether, 2-hydroxy-2- Benzoylpropane, 2-hydroxy-2- (4-isopropyl) benzoylpropane, 4-butylbenzoyltrichloromethane, 4-phenoxybenzoyldichloromethane, methyl benzoyl formate, 1,7-bis (9-acridy Nil) heptane, 9-n-butyl-3,6-bis (2-morpholino-isobutyloyl) carbazole, 2-methyl-4,6-bis (trichloromethyl) -s-triazine, 2 -Phenyl-4,6-bis Lychloromethyl) -s-triazine, 2-naphthyl-4,6-bis (trichloromethyl) -s-triazine, 4,4-bis (diphenylsulfonio) -diphenylsulphide hexafluoro Antimonate (BDSDS), 4,4- (phenylthio) phenyldiphenylsulfonium hexafluoroandimonate (PTPDS), and mixtures thereof. The method of claim 11, The multifunctional monomer may be meta-divinylbenzene, para-divinylbenzene, 4,4'-divinylbiphenylene, 1,5-divinyl naphthalene, cyclohexanedimethanol diacrylate, diethylene glycol diacrylate, Triethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, vinyl acrylate, 1,2-ethanediol diacrylate, 1,3-propanediol diacrylate, 1,3-butanediol Diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, bisphenol A diacrylate, cyclohexanedimethanol Dimethacrylate, bisphenol A dimethacrylate, methacrylated polybutadiene, triethylene glycol dimethacrylate, ethylene glycol 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentylglycol dimethacrylate, urethane acrylate, and mixtures thereof. How to. The method of claim 11, The photoacid generator may be a diazonium salt, an iodonium salt, a sulfonium salt, a diazosulfonyl compound, a sulfonyloxyimide, a nitrobenzyl sulfonate ester, a diphenyl iodonium trifluoromethane sulfonate, or a diphenyl iodonium nona Fluorobutane sulfonate, triphenylsulfonium trifluoromethane sulfonate, triazine, oxazole, oxadiazole, thiazole, phenolic sulfonic acid ester, bis-sulfonylmethane, bis-sulfonylmethane, bis- One selected from the group consisting of sulfonyldiazomethane, triphenylsulfonium tris (trifluoromethylsulfonyl) methane, diphenyliodonium bis (trifluoromethylsulfonyl) imide and mixtures thereof How to feature. The method of claim 1, The PVDF thin film produced in step 1) has a thickness in the range of 30 nm to 1 mm. The method of claim 1, UV irradiation in step 2) is carried out by irradiating UV at a wavelength of 100 to 700 nm with an output of 10 to 10,000 mJ / ㎠ for 1 to 10,000 seconds. The method of claim 1, In step 2), the solvent is ethyl acetate, butyl acetate, diethylene glycol dimethyl ether, diethylene glycol dimethylethyl ether, methyl methoxy propionate, ethyl ethoxy propionate (EEP), ethyl lactate, propylene glycol Methyl ether acetate (PGMEA), propylene glycol methyl ether, propylene glycol propyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol methyl acetate, diethylene glycol ethyl acetate, acetone, methyl isobutyl ketone, Cyclohexanone, dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), γ-butyrolactone, diethyl ether, ethylene glycol di Methyl ether, diglyme, tetrahydrofuran (THF), methanol, ethanol, propanol, iso-propanol, methyl cellosolve, ethyl cellosolve, Ethylene glycol methyl ether, diethylene glycol ethyl ether, dipropylene glycol wherein the ether is selected from toluene, xylene, hexane, heptane, octane, and mixtures thereof. The method of claim 1, And further annealing to maximize the ferroelectric properties of the patterned array of PVDF thin films formed after step 2). The method of claim 19, After heating the pattern array of the PVDF thin film on which the heat treatment was formed to a temperature above the melting point of the PVDF crystal and performing heat treatment for 1 to 30 minutes, rapidly cooling to a temperature below normal temperature, and then raising the temperature to about 10 to 100 ° C. lower than the melting point. After the heat treatment for 1 to 1,000 minutes, characterized in that the cooling is carried out to room temperature again.

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