KR100290745B1 - Optical devices using organic/silica hybrid films and fabrication method thereof - Google Patents

Abstract

The present invention relates to an electro-optical device using a composite thin film in which organic molecules having electro-optic properties are covalently bonded to a silica matrix, and a method of manufacturing the same. The composite thin film of the present invention can be produced at a low temperature using a sol-gel method, and when the optical modulator is manufactured as an electro-optical device, the optical waveguide is manufactured by the optical bleaching method, so the manufacturing method is simple. Has the advantage.

Description

Electro-optical device using organic-molecule-silica composite thin film and its manufacturing method {OPTICAL DEVICES USING ORGANIC / SILICA HYBRID FILMS AND FABRICATION METHOD THEREOF}

The present invention relates to an electro-optical device and a method of manufacturing the same, and more particularly, to an electro-optical device using a thin film of an organic molecule-silica composite, which is a kind of an electro-optic inorganic polymer, and a method of manufacturing the same.

Electro-optic optical modulators have been manufactured using inorganic crystals such as lithium niobate (LiNbO ₃ ). However, with such inorganic crystals, it was extremely difficult to fabricate a device with a modulation bandwidth of several tens of kHz due to the phase velocity mismatch between the electrical signal and light.

On the other hand, since the polar orientation polymer has a very low dielectric constant and can overcome the disadvantages of such inorganic crystals, it is possible to theoretically manufacture an electro-optical device having a modulation bandwidth of several hundred kHz. In addition, the polar alignment polymer has a number of advantages, such as large electro-optic coefficient value, suitable for integrated optical circuit application, simplify the manufacturing process of the optical modulator, and low raw material cost, has been actively studied. Until now, Mach-Zehnder optical modulators with 40 kW operating speeds were announced using PMMA (polymethylmethacrylate) polymers having a side chain of dialkylaminonitrostilbene (DANS), a nonlinear optical organic molecule. The Dalton Group of the United States has shown through experiments that operating speeds of 110 GHz or more are possible.

However, when the optical device is manufactured using the polar alignment polymer, the electro-optic coefficient value of the polar alignment polymer decreases with time and high temperature, indicating a problem in time stability and thermal stability. It has been a major obstacle to the manufacture of optical devices because it shows a large optical transmission loss compared to inorganic crystals. In order to commercialize this, the electro-optic coefficient of the polymer must not only be stably maintained at 125 ° C., which is required for photo-lithography, but also at room temperature for several years. A solution was required.

In addition, when the optical modulator is manufactured according to the related art, the optical waveguide part is manufactured by an etching process, for example, a reactive ion etching process.

Accordingly, the technical problem of the present invention is to provide an electro-optical device that is excellent in light transmittance and whose electro-optic coefficient value is thermally and temporally stable.

Another technical problem of the present invention is to provide a method for manufacturing an electro-optical device in a more simplified process.

Figure 1a is a plan view showing a schematic configuration of a Mach-gender optical modulator according to an embodiment of the present invention,

FIG. 1B is a side cross-sectional view of the Mach-Gender optical modulator along line Z-Z 'of FIG. 1A;

2 is a flow chart showing a Mach-gender optical modulator manufacturing method according to an embodiment of the present invention;

3 is a diagram showing an NMR spectral spectrum of a secondary nonlinear organic / inorganic hybrid polymer prepared by an organic molecule-silica composite coating solution used in an embodiment of the present invention.

<Explanation of symbols for main parts of drawing>

10: organic molecule-silica composite thin film

11: optical waveguide 12: photobleaching area

30: upper electrode 40: substrate

50: lower electrode 60: lower cladding layer

70: upper cladding layer

In order to achieve the above technical problem, the configuration of the present invention is largely as follows.

(a) Synthesis of a sol-gel monomer covalently bonded to a non-linear optical organic material, and sol-gel reaction of this and tetraethoxysilane (TEOS) in various composition ratios to introduce a secondary non-linear type in which an inorganic polymer medium such as SiO ₂ is introduced into the main chain. Preparation of an organic organic-inorganic polymer material and an organic molecule-silica composite thin film formed from the organic-silica composite coating solution using the same, and then applied to the electro-optical device.

The composite thin film is composed of silica, which is excellent in light transmittance and can increase the thermal and temporal stability of the electro-optic coefficient by controlling the heat treatment process.

(b) The electro-optical device includes a Mach-gender optical device formed of a three-layer structure of a lower cladding / organic molecule-silica composite thin film / upper cladding. In order to manufacture such an optical device, an electropolling process for making an organic-molecule-silica composite thin film have an electro-optic effect, a heat treatment process for curing the thin film, and a process for forming a channel waveguide using a photobleaching method are in progress. do.

In the electropolling process, the temperature is first raised above the glass transition temperature of the thin film, and then an electric field is applied to align dipoles of organic molecules in the direction of the electric field. After the resultant is maintained at a high temperature for a certain time, the temperature is lowered to room temperature while the electric field is applied, and the electric field is removed. At this time, the organic molecules are fixed between the silica base materials while being aligned in the direction of the applied electric field. Important process parameters in the polling process are polling temperature, polling time and applied voltage. Increasing the applied voltage increases the value of the electro-optic coefficient in proportion to this, and lowers the operating voltage of the device. In addition, the thermal stability of the electro-optic coefficient can be controlled by changing the polling temperature and time. In general, a long time polling at high temperature increases the thermal stability of the thin film. However, when polling at high temperatures, it is very important to properly adjust these three factors to obtain the desired thermal stability and electro-optic coefficients because overcurrent can damage the thin film and reduce the organic molecules.

In order to make an optical modulator among electro-optical devices, a single mode channel waveguide structure is essential. The organic molecule-silica composite thin film exhibits a photobleaching phenomenon in which the refractive index of the thin film is slightly reduced when irradiated with strong ultraviolet rays. Ultraviolet irradiation can easily induce a change in refractive index of about 0.01, and it is possible to precisely change the refractive index by adjusting the irradiation time. When the channel waveguide is made using the photobleaching phenomenon, the light scattering loss can be reduced and the manufacturing process is much simpler than the rib waveguide or the channel waveguide made using the conventional reactive ion etching. .

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention.

In this embodiment, the Mach-gender optical modulator will be described in detail.

[Production of Mach-Gender Light Modulator]

Mach-Gender optical modulator basically has a Y-branch that splits the light into two parts or combines the two lights, an active area that causes a difference in the phase velocity of the waveguide mode by applying a voltage, and the input and output of the light. Can be divided into areas. In order to make the Mach-gender optical modulator as described above, a single mode optical waveguide structure is essential. The optical waveguides shown in FIGS. 1A and 1B are designed so that only a single mode can be excited for TM (Transverse Magnetic) polarization. For this purpose, the width of the waveguide, the thickness of the thin film and the photobleaching time should be adjusted to appropriate values.

Figure 1a is a plan view showing a schematic configuration of a Mach-gender optical modulator according to an embodiment of the present invention. In more detail, it is a plan view showing a schematic configuration in which the upper electrode is located on the optical waveguide formed in the organic molecule-silica composite thin film layer itself. Referring to FIG. 1A, an organic molecule-silica composite thin film layer 10 is formed on a substrate having a predetermined process. The organic molecule-silica composite thin film layer 10 includes an optical waveguide 11 and a photobleaching region 12 having different refractive indices.

In addition, the optical waveguide 11 extends to the end of the substrate, and the substrate forms a fracture surface cleaved to allow the optical signal to input and output at both ends of the optical waveguide 11.

In order to induce modulation in the optical signal passing through the optical waveguide 11, the upper electrode 30 having a predetermined length in the active region is located on the branched optical waveguide 11.

FIG. 1B is a side cross-sectional view of the Mach-Gender optical modulator according to Z-Z ′ of FIG. 1A. Referring to FIG. 1B, a lower electrode 50 formed by thermally depositing a metal is formed on a silicon substrate 40, and a lower cladding layer 60 formed by spin coating a suitable polymer on the lower electrode 50. Is formed.

On the lower cladding layer 60, an organic molecule-silica composite thin film layer 10 in which a polymer matrix is made of silica using a sol-gel process and covalently bonded with organic molecules that exert an electro-optic effect is formed. The optical waveguide 11 is formed in the organic molecule-silica composite thin film layer 10 itself, and the optical bleaching region 12 having a refractive index different from that of the optical waveguide 11 due to the photobleaching effect in portions except the optical waveguide 11. There is).

On this organic molecule-silica composite thin film layer 10, an upper cladding layer 70 formed by spin coating a suitable polymer is formed thereon, which is located above the optical waveguide 11 and modulated to an optical signal passing therethrough. An upper electrode 30 formed to induce is formed. The length of the active region in which the upper electrode 30 is formed can be arbitrarily adjusted.

The Mach-gender optical modulator configured as described above converts an electric signal applied from the outside into an optical signal. As shown in Fig. 1A, when the TM polarized light (laser beam) is incident on the optical waveguide 11 through the left fractured surface, which is an input region, the light is divided into two branches at the Y-branch, and the active region is separated. Afterwards, it goes through the Y-branch and proceeds to the output stage. At this time, the lower electrode 50 is grounded, and a constant bias voltage is applied to one of the two upper electrodes 30.

In this case, when an input electric signal is applied to the other upper electrode 30, the phase of light traveling by the electro-optic effect is changed. Light having different phases passing through both optical waveguides 11 causes interference, and the phase is changed, and this phase change is changed to change in intensity of light. The result is output to the right fracture surface which is the output area. As such, when the electrical signal is converted into an optical signal and output, and the modified and output optical signal is analyzed, the input electrical signal may be inferred.

The magnitude of the applied voltage required until the output signal is turned from an on state to an off state is called an operating voltage of the device. The magnitude of the operating voltage is the length of the active region and the magnitude of the electro-optic coefficient. Proportional to, and inversely proportional to the overall thickness of the device. In the present invention, the operating voltage was measured as 13V at 1.3㎛ wavelength when the active region of the device is 15mm in length.

The optical modulator manufacturing method configured as described above will be described with reference to FIG.

In the present embodiment, the organic-molecule-silica may be manufactured through a sol-gel process as well as a process of manufacturing a Mach-gender optical modulator formed of a three-layer structure of an upper cladding layer / organic molecular-silica composite thin film layer / lower cladding layer on a substrate. It also includes a process of synthesizing the composite coating solution.

First, a bottom electrode is formed by thermally depositing a metal on a silicon substrate (S1).

On the lower electrode, a lower cladding layer is formed (S2). At this time, the lower cladding layer is formed by spin coating a polymer.

On this lower cladding layer, an organic molecule-silica composite thin film layer is formed (S3).

On this organic molecule-silica composite thin film layer, spin coating the polymer again to form an upper cladding layer (S4), and heat-treat the thin film composed of three layers on a hot plate to remove the solvent inside the thin film and the organic molecular-silica composite thin film layer Some hardening is to occur (S5). This heat treatment process is a preliminary step for electric polling. If this is not done, a large amount of current flows during electric field polling to damage the thin film. At this time, heat treatment is preferably performed at 160 to 200 ° C for 20 to 30 minutes.

Next, a first metal layer is formed and patterned into an optical waveguide extending to an end of the substrate to fabricate a photobleaching mask (S6).

The optical waveguide is formed on the organic-molecule-silica composite thin film layer by irradiating light to the resultant on which the photobleaching mask is fabricated and utilizing the photobleaching effect (S7).

On the resultant waveguide formed thereon, a second metal layer is formed by thermal evaporation for electric polling (S8).

Then, the organic molecules in the organic molecule-silica composite thin film layer are polarized (S9). In order to effectively perform this polarization, it is preferable to polarize the organic molecules by using a direct current electropolling method which applies a DC voltage between the lower electrode and the second metal layer while heating the resultant on which the second metal layer is formed. . In addition, this DC electropolling method is suitably performed at 150-200 degreeC for 1 to 20 hours.

After the polling process, the second metal layer is chemically etched to form an upper electrode (S10). After the forming of the upper electrode, an end surface of the substrate is cleaved so that light can input and output to both ends of the waveguide (S11).

The Mach-gender optical modulator, which has undergone the manufacturing process as described above, has excellent light transmittance by using silica as a matrix and can increase the thermal stability of the electro-optic effect through heat treatment. In addition, it can be seen that the manufacturing process of the optical device is simplified by using the optical bleaching effect when manufacturing the Mach-gender optical modulator.

Here, the Mach-gender optical modulator has been described as an example, but other electro-optic devices may also be fabricated by forming an organic molecule-silica composite thin film layer followed by electropolling.

Next, an embodiment of the synthesis of the secondary nonlinear optical organic / inorganic polymer material using the sol-gel process and the preparation of the organic molecular-silica composite thin film using the same will be described.

[Synthesis of Secondary Nonlinear Optical Organics DANS]

The synthesis of the secondary nonlinear optical organic compound DANS is shown in Scheme 1 below.

The chemical reaction is carried out through the following six steps.

(1) Synthesis of N, N-di (2-benzooxyethyl) -aniline

Aniline-N, N-diethanol (60 g, 0.34 mol) and triethylamine (130 mL) were dissolved in 400 mL of tetrahydrofuran (THF), and benzoyl chloride (76.8 mL, 0.68 mol) was added dropwise at 0 ° C. . The reaction is stirred for 3 h at 0 ° C. and poured into H ₂ O (1 L). The precipitate was collected and recrystallized in methanol to obtain N, N-di (2-benzoxyethyl) -aniline having a melting point of 72 to 74 ° C. at a yield of 92%.

(2) Synthesis of 4- [N, N-di (2-benzooxyethyl)] benzaldihydr

Phosphorus oxychloride (24 mL, 0.25 mol) was added dropwise to 80 mL of dimethylformamide (DMF) at 0 ° C. for 1 hour and N, N-di (2-benzox) dissolved in DMF (50 mL) for 1 hour. Ethyl) -aniline (100 g, 0.25 mol) was added dropwise at room temperature for 1 hour and then stirred at 90 ° C for 12 hours. The reaction product was poured into ice (300 g) and extracted three times with methyl chloride. Thereafter, the solvent was removed and recrystallized in methanol to obtain 4- [N, N-di (2-benzoxaethyl)] benzaldihydr having a melting point of 79 to 100 ° C. at a yield of 79%.

(3) Synthesis of N- [4-N, N- (di-2-benzoxyethylamino) -benzylidene] aniline

When toluene (600 mL) and 4- [N, N-di (2-benzooxyethyl)] benzaldihydride (100 g, 0.24 mol) are added to a flask equipped with a DSt (Dean Stark trap) and all aldehyde groups are dissolved. The temperature is gradually raised to 60 ° C. To this is added aniline (23.4 mL, 0.25 mol) and refluxing, if no further water is formed in D.S.t, the mixture is cooled and hexane (600 mL) is added. The formed precipitate is collected and dried to obtain N- [4-N, N- (di-2-benzoxyethylamino) -benzylidene] aniline having a melting point of 118 占 폚 with a yield of 87%.

(4) Synthesis of N- [N, N-di- (2-benzooxyethyl) amino] -4'-nitrostilbene

N- [4-N, N- (di-2-benzoxyethylamino) -benzylidene] aniline (115 g, 0.23 mol) is added to toluene (800 mL) and stirred at 50 ° C. for 30 minutes. Then p-nitrophenylacetic acid (50 g, 0.28 mol) is added slowly and stirred for 12 hours. Then acetic acid (30 g, 0.5 mol) was slowly added dropwise to the mixture and refluxed for 2 hours to remove carbon dioxide. After the reaction was completed, the mixture was cooled, the solvent was removed under reduced pressure, poured into methanol (500 mL), and the precipitate was collected and dried to obtain a yield of 73%. N- [N, N-di- (2-benzoxylethyl) having a melting point of 126 to 128 ° C. Amino] -4'-nitrostilbene is obtained.

(5) Synthesis of 4- [N, N-di- (2-hydroxyethyl) amino] -4'-nitrostilbene

N- [N, N-di- (2-benzoxylethyl) amino] -4'-nitrostylbene (54 g, 0.1 mol) is dissolved in THF (300 mL), ethanol (200 mL) is added and a little KOH After addition of the aqueous solution, the mixture was refluxed for 6 hours. After cooling, the precipitate was filtered off and the filtrate was recrystallized with ethanol to yield 60% yield of 4- [N, N-di- (2-hydroxyethyl) amino] -4 having a melting point of 184 to 186 캜. '-Get Nitrostilbene.

(6) Synthesis of 4- [N, N-di- (2-driethoxysilaneoxyethyl) amino] -4'-nitrostilbene

4- [N, N-di- (2-hydroxyethyl) amino] -4'-nitrostilbene (0.82 g, 2.5 × 10 ^-3 mol) was added to 20 mL of dimethylacetamide (″ DMAc ″). Dissolve. 3-isocyanatopropyldrieethoxysilane (1.2 g, 5 × 10 ^-3 mol) was added to this solution, and reflux was applied at 110 DEG C under a nitrogen atmosphere to give 4- [N, N-di- (2- Drieethoxysilaneoxyethyl) amino] -4'-nitrostilbene is obtained. This material is used as the in-situ of the sol-gel process.

[Synthesis of Secondary Nonlinear Optical Organic / Inorganic Polymeric Materials]

First, the synthesis route of the second nonlinear optical organic / inorganic polymer material by the sol-gel monomer and the sol-gel process is shown in Scheme 2.

The polymerization process by the sol-gel process was as follows.

TEOS and excess acidic solution (2N) were added to 4- [N, N-di- (2-driethoxysilaneoxyethyl) amino] -4'-nitrostilbene obtained in the synthesis of the secondary nonlinear optical organic DANS. By polymerization and copolymerization. The solution obtained here was stirred at room temperature for 3 days and subjected to hydrolysis and condensation polymerization to obtain a solution with increased viscosity. After condensation polymerization, the solution becomes a sol solution with viscosity. Using this sol solution, a thin film could be easily formed on the substrate by spin coating, and a second nonlinear organic / inorganic hybrid polymer having a very good thermal stability was synthesized by a subsequent heat curing process. ²⁹ Si-NMR spectroscopy was performed while observing the polycondensation reaction of triethoxysilane and TEOS containing nonlinear optical properties. 3 shows the ²⁹ Si Magic Angle Spinning (MR) NMR spectral spectrum of the sol-gel material. T species is monomeric and means silicon with three oxygen groups. Q is TEOS and means silicon with four oxygen groups. Where T refers to trihydroxy (T ⁰ ), dihydroxy (T ¹ ), monohydroxy (T ² ) and non-hydroxy (T ³ ) states. In addition, Q represents tetrahydroxy (Q ⁰ ), trihydroxy (Q ¹ ), dihydroxy (Q ² ), monohydroxy (Q ³ ) and non-hydroxy (Q ⁴ ) states. it means. Referring to Figure 3, T ¹ (49.5ppm), T ² (56.6ppm), T ³ (65.1ppm), and observed as Q ¹ (81.0ppm), Q ² (90.0ppm), Q ³ (99.4ppm) It became. After curing for 3 hours at 170 ℃ using a ²⁹ Si-NMR spectroscopy to confirm the chemical structure, there was no T ¹ , Q ¹ and Q ² , only peaks of T ³ and Q ⁴ (109.2 ppm) could be seen. This means that it is fully polycondensed. The maximum absorption wavelength (λ _max ) absorption region of the DANS dye from the UV-visible spectrometer was found at 450 nm. In addition, the absorption after the polar orientation and the thermal curing reaction decreased. This shows that the alignment of nonlinear optical pigment molecules is well achieved. As a result of X-ray diffraction experiment on the synthesized polymer, the X-ray diffraction width was wide and the Δ (2θ) / (2θ) value was larger than 0.5, indicating that the synthesized secondary nonlinear organic / inorganic hybrid polymer material was amorphous. It was found to be a polymeric material in the form.

[Production and Polarization of Organic Molecule-Silica Composite Thin Films by Sol-Gel Process]

After cooling the solution obtained in the synthesis process of the above-mentioned second nonlinear optical organic / inorganic polymer material to room temperature, adding HCl aqueous solution and continuously stirring at room temperature, the sol-gel reaction proceeds and the viscosity of the solution gradually increases. . After the passage of time, the viscosity of the solution reaches an appropriate level. The filter is filtered through a membrane filter and a thin film is formed on the substrate by spin coating.

After spin coating, the thin film is heat-treated to evaporate the solvent in the thin film, and a slight hardening occurs in the thin film. If the heat-treating process is not carried out, a severe current flows during electric field polling and the thin film is damaged.

The technical effects produced by the present invention are as follows. In the near future, the demand for optical devices that operate at high speed will increase, and accordingly, the fabrication of optical devices using polymers will be greatly highlighted. However, in the case of existing electro-optic polymers, thermal and temporal relaxation of the electro-optic coefficient and large optical transmission loss have been a major obstacle to the practical use. However, the optical device using the organic-molecule-silica composite thin film proposed in the present invention can operate at high speed because the organic-molecule-silica composite thin film not only has excellent light transmittance but also improves the thermal stability of the device by a simple heat treatment method. There is an advantage.

In addition, there is an advantage that the optical device fabrication process is simplified by using the optical bleaching method in forming the optical waveguide during the optical device fabrication process.

Claims (13)

A substrate; A lower electrode formed on the substrate; A lower cladding layer formed on the lower electrode; An organic molecule-silica composite thin film layer formed on the lower cladding layer to form an optical waveguide by having an electro-optic effect by electropolling; An upper cladding layer formed on the organic molecule-silica composite thin film layer; And an upper electrode formed on the optical waveguide. The electro-optical device according to claim 1, wherein the upper electrode serves as an optical modulator by inducing modulation to an optical signal passing through the optical waveguide. The organic non-silicon composite thin film layer according to claim 1 or 2, wherein the organic non-silicon composite thin film layer is a secondary nonlinear organic molecule and 3-isocyanatopropyl tree containing two hydroxy groups in an N, N'-dimethylformamide solvent. An electro-optical device comprising a urethane bond by reaction with ethoxysilane and then made from a coating solution using a sol-gel monomer of the formula as an intermediate. The method of claim 3, wherein the secondary nonlinear organic molecular material is: (1) After dissolving aniline-N, N-diethanol and triethylamine in tetrahydrofuran, the reaction mixture was added dropwise with benzoyl chloride, stirred, added to H ₂ O, and the resulting precipitate was recrystallized in methanol to give N, N- Obtaining di (2-benzoxyethyl) -aniline; (2) Add dropwise phosphorus oxychloride to DMF, add N, N-di (2-benzooxyethyl) -aniline dissolved in DMF dropwise and stir, and pour the reaction result on ice and use methyl chloride Extracting to remove the solvent and recrystallization from methanol to obtain 4- [N, N-di (2-benzooxyethyl)] benzaldihydr; (3) Toluene and 4- [N, N-di (2-benzoxylethyl)] benzaldihydride were added to the flask equipped with DSt, and the temperature was raised until all aldehyde groups were dissolved. Then, aniline was added and refluxed. If no more water is formed in the DSt, the mixture is cooled and hexane is added to collect and dry the formed precipitate to obtain N- [4-N, N- (di-2-benzoxyethylamino) -benzylidine] aniline. Steps; (4) The above-mentioned N- [4-N, N- (di-2-benzoxyethylamino) -benzylidene] aniline was added to toluene, followed by stirring, followed by addition of p-nitrophenylacetic acid, followed by stirring. The reaction was carried out by dropwise adding acetic acid, and then the solvent was removed, poured into methanol, and the precipitate was collected and dried to obtain N- [N, N-di- (2-benzooxyethyl) amino] -4'-nitrostilbene; ; (5) The above N- [N, N-di- (2-benzoxylethyl) amino] -4'-nitrostilbene was dissolved in THF, ethanol and KOH aqueous solution were added, and the reaction precipitate was filtered off. Recrystallizing the filtrate with ethanol to obtain 4- [N, N-di- (2-hydroxyethyl) amino] -4'-nitrostilbene; (6) The above 4- [N, N-di- (2-hydroxyethyl) amino] -4'-nitrostilbene was dissolved in DMAc and 3-isocyanatopropyldriethoxysilane was added to this solution. And sequentially applying reflux under a nitrogen atmosphere, An electro-optical device, characterized in that it is a DANS-based nonlinear optical organic material obtained by synthesizing 4- [N, N-di- (2-diethoxysilaneoxyethyl) amino] -4'-nitrostilbene. The method of claim 3, wherein the organic molecule-silica composite thin film layer, The sol-gel monomer and TEOS sol-gel reaction to introduce an inorganic polymer medium SiO ₂ to the main chain and then formed using a second non-linear organic-silica polymer of the formula. The method of claim 5, wherein the polymer material is: Adding TEOS and an acidic solution to the 4- [N, N-di- (2-diethoxysilaneoxyethyl) amino] -4'-nitrostilbene to obtain a solution polymerized and copolymerized; Electro-optic device, characterized in that it is made through the step of obtaining a sol solution by stirring and hydrolysis and condensation polymerization of the solution. Forming an organic molecule-silica composite thin film layer; Hardening the organic molecule-silica composite thin film layer by heat treatment; Electropolling the organic molecule-silica composite thin film layer to have an electro-optic effect. The method of claim 7, wherein Formation of the organic molecule-silica composite thin film layer is: Depositing a metal on the substrate to form a lower electrode; After the step of forming a lower cladding layer on the lower electrode, The heat treatment of the organic molecule-silica composite thin film layer is: After the further step of forming an upper cladding layer on the organic molecule-silica composite thin film layer, The electropolling of the organic molecule-silica composite thin film layer is: Forming a first metal layer on the upper cladding layer, and patterning the first metal layer into an optical waveguide extending to an end of the substrate to form a photobleaching mask; Forming an optical waveguide on the organic molecule-silica composite thin film layer by using light bleaching effect by irradiating light to the resultant on which the photobleaching mask is formed; After the step of forming the second metal layer on the resultant waveguide is formed in order to polarize the organic molecules in the organic molecule-silica composite thin film layer, And after the electropolling step, forming an upper electrode by etching the second metal layer to manufacture an optical modulator. The method of manufacturing an electro-optical device according to claim 7 or 8, wherein the process parameters to be adjusted and optimized during the electropolling are polling temperature and polling time. The method of claim 9, wherein the electric polling step is: Method for producing an electro-optical device, characterized in that the direct current electropolling method for applying a direct current voltage to the organic molecule-silica composite thin film layer. The method of claim 10, wherein the heat treatment performed to cure the organic molecule-silica composite thin film layer before applying the direct current electropolling method is performed for 20 to 30 minutes at 160 ~ 200 ℃. Way. The method of manufacturing an electro-optical device according to claim 10, wherein the direct current electropolling method is performed at 150 to 200 캜 for 1 to 20 hours. The method of manufacturing an electro-optical device according to claim 8, wherein the optical waveguide formed by using the optical bleaching effect is a single mode optical waveguide.