KR100862002B1 - Surface treatment method of substrate and manufacturing method of substrate - Google Patents

Abstract

Disclosed are a method of treating a substrate and a method of manufacturing the substrate. Preparing a coating solution composed of a compound comprising a fluorocarbon solvent and an acrylate solute, coating the surface of the substrate with the coating solution, and drying the coated substrate. In the method for treating a surface of a substrate, the spreadability of the droplets can be easily adjusted for forming a fine wiring of the substrate, and the adhesion to the substrate can be improved.

Description

Method for treatment of substrate surface and method for manufacturing substrate

1 is a flow chart showing a method of manufacturing a substrate according to an embodiment of the present invention.

Figure 2 is a schematic diagram showing the ink is ejected in an inkjet method on a substrate prepared according to a preferred embodiment of the present invention.

3 is a schematic diagram illustrating a method of measuring the contact angle of ink on a substrate.

<Explanation of symbols for the main parts of the drawings>

10 inkjet head 20 conductive ink

30 surface treatment film 40 substrate

50: contact angle

The present invention relates to a surface treatment method of a substrate and a method of manufacturing the substrate.

Due to the simplicity of the process, the possibility of mass production, and the environmental friendliness, much research is being conducted to apply an inkjet method which can easily print an arbitrary pattern in a non-contact manner to form a circuit of an electronic component.

In such an inkjet method, in order to realize a fine pattern, the droplet size control of the ejected ink, the ink spreadability and the adhesive force on the substrate serve as important factors.

A conventional method for reducing the wiring width in an inkjet patterning operation is a method of suppressing the spreadability of ink by applying a silicone gel-like compound to a substrate to perform water repellent treatment.

According to the method as described above, the spreadability of the ink can be suppressed to some extent, but the thickness of the surface treatment layer and the adhesion of the ink to the substrate is very poor, so it is difficult to apply to the process.

In addition, there is a method of suppressing spreading on a substrate by reducing the drop size of the ejected ink to a femto size, that is, ^10-15 m. However, the above method has technical limitations because it is very difficult to reduce the drop size of the ink may cause various problems.

Therefore, the spreadability of the droplets discharged by the inkjet method can be controlled, and the adhesion between the droplets and the substrate can be improved, and the surface treatment method of the substrate including the fine wiring required by the electronic component that is required to be small, light and thin It is a desperate situation.

The present invention provides a substrate treatment method and a method of manufacturing a substrate that can easily adjust the spreadability of the liquid droplets to form a fine wiring of the substrate and improve the adhesion to the substrate.

According to an aspect of the present invention, preparing a coating solution consisting of a compound comprising a fluoro carbon solvent and an acrylate-based solute, coating the surface of the substrate with a coating solution and coating It provides a surface treatment method of a substrate comprising the step of drying the substrate.

The fluorocarbon solvent may be at least one compound selected from the group consisting of C ₂ F ₆ , C ₆ F ₁₄ , C ₇ F ₁₆ , C ₈ F ₁₈ , C ₉ F ₂₀ .

The acrylate-based solute may be a solute including at least one compound selected from the group consisting of polyacrylate, polyalkylacrylate, and polymethacrylate, preferably methyl methacryl. Methylmethacrylate-MMA.

The coating solution may further include a fluoroalkylsilane-based solute in the compound.

Fluoroalkyl silane solutes include trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane and (heptadeca-fluoro-1,1,2,2-tetrahydro-decyl) -1-tri It may be at least one compound selected from the group consisting of methoxysilane.

An acrylate solute may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the fluorocarbon solvent.

The acrylate solute may be included in an amount of 0.1 to 5 parts by weight and the fluoroalkylsilane solute may be included in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the fluorocarbon solvent.

The substrate may be made of at least one of polyimide and epoxy, and the substrate may be characterized in that it is porous.

Coating steps include spin coating, roll coating, dip coating, screen coating, spray coating, screen printing and ink jet It may be carried out using any one selected from the group consisting of, and may be coated with a thickness of 0.1 to 1 ㎛ on the substrate in the coating step.

According to another aspect of the invention, preparing a coating solution consisting of a compound comprising a fluoro carbon solvent and an acrylate-based solute, coating the surface of the substrate with a coating solution, coating It provides a method for manufacturing a substrate comprising the step of drying the dried substrate, forming a wiring with a conductive ink on the dried substrate and heat-treating the substrate.

The conductive ink is at least one selected from the group consisting of silver (Ag), copper (Cu), nickel (Ni), gold (Au), platinum (Pt), palladium (Pd), iron (Fe), and alloys thereof It may include metal nanoparticles.

The wiring forming step may be performed by discharging the conductive ink by an inkjet method, preferably, the width of the wiring is 20 to 100 μm, and the contact angle between the substrate and the wiring is 40 to 50 °.

In addition, the heat treatment step may be performed for 0.5 to 2 hours at a temperature of 150 to 250 ℃.

Other aspects, features, and advantages other than those described above will become apparent from the following drawings, claims, and detailed description of the invention.

Hereinafter, a preferred embodiment of the surface treatment method of the substrate according to the present invention will be described in detail with reference to the accompanying drawings, in the description with reference to the accompanying drawings, the same or corresponding components are given the same reference numerals and Duplicate explanations will be omitted.

Factors affecting the spreadability of the ink include the properties of the ink, the size and concentration of the metal particles contained in the ink, the size of the nozzle, the size or surface tension of the droplets ejected, the relationship between the properties of the ink and the substrate on which the ink is ejected, And surface energy or surface treatment state of the substrate.

At this time, assuming that the size of the ejected droplets is constant, the mechanical relationship between the surface tension of the ink and the surface energy of the substrate becomes an important variable. For example, if the surface tension of the ink is greater than the surface energy of the substrate, the spreadability of the ink will be small. On the contrary, if the surface tension of the ink is less than the surface energy of the substrate, the spreadability of the ink is increased.

Therefore, when the size and surface tension of the ink droplets are the same, it is possible to improve the spreadability of the ink if the surface energy of the substrate is lowered. The spreadability of the ink may be measured at a contact angle, and the surface energy of the substrate may be controlled through corona discharge, plasma treatment, ion beam treatment, and fluoro compound treatment.

1 is a flow chart showing a method of manufacturing a substrate according to an embodiment of the present invention. The present embodiment provides a method of treating a substrate and a method of manufacturing the substrate which treats the substrate with a fluoro acrylate compound and lowers the surface energy of the substrate through heat treatment.

To this end, first, a coating solution composed of a compound including a fluorocarbon solvent and an acrylate solute is prepared (100). As in this embodiment, the surfactant containing fluoro (F) is prepared by substitution reaction of a water-soluble functional group at the terminal in the hydrophobic linear molecule containing a fluoro atom, and has the best surface tension resistance among the existing surfactants. . Such fluoro-based surfactants are highly functional surfactants having excellent repulsion against water and oil and good chemical resistance.

The fluorocarbon solvent may be at least one compound selected from the group consisting of C ₂ F ₆ , C ₆ F ₁₄ , C ₇ F ₁₆ , C ₈ F ₁₈ , C ₉ F _20, and mixtures thereof.

In addition, the acrylate-based solute is a solute including at least one compound selected from the group consisting of polyacrylate, polyalkylacrylate and polymethacrylate, preferably methyl meth It may be an acrylate (Methylmethacrylate-MMA).

After the surface treatment by coating a compound containing an acrylate solute in a fluorocarbon solvent to the substrate, it is possible to improve the contact angle between the ink droplet and the substrate discharged by the inkjet method.

In order to form a more preferable contact angle, that is, to prevent the formation of an excessive contact angle, it is possible to lower the surface energy of the ink droplets to an appropriate range by adding a material that lowers the water repellency. That is, by adding a fluoroalkylsilane-based solute to the compound, the surface energy of the ink droplets can be controlled within an appropriate range, and the circuit pattern of the substrate can be more easily implemented. More specifically, after coating the compound to which the fluoroalkylsilane-based solute is added to the substrate, the contact angle of the ink droplets may be measured to implement a preferred contact angle of about 40 degrees to about 50 degrees.

Fluoroalkyl silane solutes include trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane and (heptadeca-fluoro-1,1,2,2-tetrahydro-decyl) -1-tri It may be at least one compound selected from the group consisting of methoxysilane.

The coating solution of this embodiment may be prepared by mixing 0.1 to 5 parts by weight of an acrylate solute based on 100 parts by weight of a fluorocarbon solvent. When mixing at such a ratio and surface-treating the substrate, it is possible to form a fine pattern of the substrate by increasing the surface energy of the ink droplets.

In addition, when fluoroalkylsilane-based solutes are added to lower the excessive surface energy of the ink droplets, 0.1 to 5 parts by weight of acrylate-based solutes and fluoroalkylsilane-based solutes may be added to 100 parts by weight of the fluorocarbon solvent. It may be prepared by mixing 0.1 to 5 parts by weight. As described above, when the surface treatment is performed on the substrate by mixing in such a ratio, the fine pattern of the substrate may be formed by lowering the surface energy of the substrate and increasing the surface energy of the ink droplets.

Thus when a solvent that has the same component substrate, such as treatment of a polyimide substrate surface of the substrate because it has an fluoroalkyl silane groups to form a stable bond in combination with the amine group of the substrate, the surface of CF ₃ will get wet Modified.

That is, a surface treatment film having low surface energy is formed. Herein, the substrate may be used without limitation as long as it is a substrate capable of stably forming a surface treatment film when applied with a fluoro-containing material of the present invention, and may be made of at least one of polyimide and epoxy, but may be made of polyimide substrate. This is preferred.

Since the substrate provided in this embodiment is porous, the surface energy is very high. Thus, the ink droplets spread widely on the porous surface. However, since the porous surface functions to fix by acting as an anchor, very high adhesion can be realized.

Therefore, by coating a coating solution composed of a compound containing an acryl lake-based solute in a fluorocarbon solvent on a substrate, the surface energy of the substrate can be lowered to easily implement a conductive circuit pattern formed on the substrate and to enable fine wiring. In addition, as the substrate is formed to be porous, ink droplets may be fixed to improve adhesion between the substrate and the circuit pattern.

Next, a coating solution composed of a compound containing an acrylic lake-based solute in a fluorocarbon solvent is coated on the substrate (200). Coating methods include spin coating, roll coating, dip coating, screen coating, spray coating, screen printing and ink jet. ) Or various methods such as vapor deposition (CVD), but are not necessarily limited thereto.

In this embodiment, the coating is performed by dip coating, and the substrate is dipped in the coating solution for 10 seconds and then pulled out.

In addition, it can be coated with a thickness of 0.1 to 1 ㎛ on the substrate. If the coating thickness is less than 0.1 μm, the surface energy of the substrate may not be sufficiently lowered, which may cause a problem in that the micropattern is not easily implemented. It can cause a lot of problems.

Next, the coated substrate is dried (300). The coated substrate is dried in air for about 10 seconds.

The surface treatment method for lowering the surface energy of the substrate has been described above. Hereinafter, a method of manufacturing the substrate including these steps will be described. In the method of manufacturing a substrate of the present invention, as described above, a wire may be formed of conductive ink on the substrate on which the surface treatment film is formed (400), and the substrate may be heat treated (500).

Here, the conductive ink is prepared by a conventional method in the art, and divided into aqueous or non-aqueous inks depending on the nature of the solvent mixed with the metal particles. For example, the conductive ink is selected from the group consisting of silver (Ag), copper (Cu), nickel (Ni), gold (Au), platinum (Pt), palladium (Pd), iron (Fe), and alloys thereof. It may comprise one or more metal nanoparticles.

The wiring forming method of the substrate may be performed by discharging the conductive ink by an inkjet method. The size of these metal nanoparticles tends to become smaller to form microwires. Generally, metal nanoparticles of about 5 to 20 nm, preferably about 5 nm are used in conductive inks.

In addition, solvents of non-aqueous inks are not limited thereto, but hydrocarbon-based compounds are generally used. Specific examples thereof include hexane, octane, decane, tetradecane, hexadecane, 1-hexadecine, 1-octadecine, toluene, At least one may be selected from the group consisting of xylene and chlorobenzoic acid. Double toluene, xylene, 1-hexadecine, chlorobenzoic acid, tetradecane or 1-octadecine can be preferably used.

In addition, the solvent of the aqueous ink is not limited thereto, and for example, diethylene glycol butyl ether acetate, an ethanol aqueous solution, and ethylene glycol can be used.

The method of forming the wiring with the conductive ink includes a method of screen printing, gravure printing, inkjet printing, and the like, and an inkjet method is preferable to form a double fine wiring.

Next, as the heat treatment of the substrate on which the circuit pattern is formed by the inkjet method, the bonding force between the surface treatment film and the substrate may be increased to form a stable surface treatment film. This process can be carried out in the same manner as a conventional heat treatment method in the art, for example, the entire substrate may be supplied to an electric oven or a drying oven to apply heat. The heat treatment may be performed for 25 to 30 minutes at a temperature of 200 to 250 ℃.

If the temperature of the heat treatment is less than 200 ℃ and the heat treatment time is less than 25 minutes, the substrate and the ink wiring is not coupled stably, and if the heat treatment temperature exceeds 250 ℃ and the heat treatment time exceeds 30 minutes, the substrate is deformed Can cause problems.

Figure 2 is a schematic diagram showing the ink is discharged on the substrate prepared in accordance with a preferred embodiment of the present invention, Figure 3 is a contact angle of the ink on a substrate prepared in accordance with a preferred embodiment of the present invention It is sectional drawing to show. Referring to FIG. 2, an inkjet head 10, a conductive ink 20, a surface treatment film 30, a substrate 40, and a contact angle 50 are illustrated.

In the present embodiment, the wiring forming method may be formed by an inkjet method as illustrated in FIG. 2, and the substrate on which the surface treatment film 30 is coated with conductive ink 20 formed by droplets falling from the inkjet head 10 may be coated. The circuit pattern may be embodied by discharging at 40.

The contact angle 50 of the conductive ink 20 formed on the substrate 40 can be measured as shown in FIG. 3, preferably forming a contact angle of 40 ° to 50 °. If the contact angle between the conductive ink 20 and the substrate 40 is less than 40 °, the circuit pattern of the fine wiring may not be realized. If the contact angle exceeds 50 °, the surface energy of the conductive ink 20 increases. Accordingly, as the droplets of the conductive ink 20 are formed in a dot form, a problem in that a linear circuit pattern may not be realized may occur.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are for illustrative purposes only and are not intended to limit the present invention.

Example 1

A coating solution was prepared by mixing 0.2 g of a solute (3M, Novec EGC-1700) of methyl methacrylate (Methylmethacrylate-MMA) with 99.8 g of a C ₂ F ₆ solvent (3M, HFE-7100). The polyimide substrate having a thickness of 50 μm was impregnated into the treatment tank containing the coating solution for about 10 seconds, and then taken out and naturally dried. The coated substrate was cured by sintering at 250 ° C. for 30 minutes. The non-aqueous ink of the tetradecane solvent containing about 20 nm of silver nanoparticles was discharged onto the surface-treated substrate using a nozzle having a diameter of 35 μm. At this time, the surface tension of the non-aqueous ink was 28.8 dyne / cm. After repeating this five times, Table 1 measured the contact angle between the substrate and the ink. As the average of the contact angles was 52.7 °, it was found that the contact angle was increased to reduce the spreadability of the ink.

TABLE 1

1 time Episode 2 3rd time 4 times 5 times Contact angle (degrees) 52.3 51.0 54.8 53.1 52.5

Example 2

0.2 g of methyl methacrylate (MM) solute (3M, Novec EGC-1700) was mixed with 99.8 g of C ₂ F ₆ solvent (3 M, HFE-7100), followed by fluoroalkylsilane solute (3 M, EGC-1720) 0.2g was mixed to prepare a coating solution, except that the contact angle between the discharged ink droplets and the substrate was measured. The results are shown in Table 2 below. As the average of the contact angle was 46.4 °, when compared with Example 1, the contact angle was lowered to form a more stable contact angle and it was found that the spreadability of the ink was reduced.

TABLE 2

1 time Episode 2 3rd time 4 times 5 times Contact angle (degrees) 47.3 44.2 45.8 49.0 45.7

Comparative example

The contact angle between the discharged ink droplet and the substrate was measured by performing the same process except that the polyimide substrate was not surface treated in the above example, and the results are shown in Table 3 below.

TABLE 3

1 time Episode 2 3rd time 4 times 5 times Contact angle (degrees) 0 One 0 0 One

As shown in Examples 1, 2 and Comparative Examples, according to the surface treatment method of the substrate according to the present invention, the spreadability of the ink can be reduced by about 900% compared to the case where the surface treatment is not performed, and the contact angle is improved. Can be.

In addition, by adding a fluoroalkylsilane-based solute to the compound, the contact angle between the coating ink and the substrate tube could be maintained within an appropriate range.

The present invention is not limited to the above embodiments, and many variations are possible by those skilled in the art within the spirit of the present invention.

As described above, according to the preferred embodiment of the present invention, the surface energy of the substrate may be lowered and the surface energy of the conductive ink may be increased to implement the microcircuit pattern of the substrate. In addition, since the substrate is porous, adhesion between the substrate and the conductive ink can be improved.

Claims (17)

A fluorocarbon solvent and at least one compound selected from the group consisting of C ₂ F ₆ , C ₆ F ₁₄ , C ₇ F ₁₆ , C ₈ F ₁₈ , and C ₉ F ₂₀ , and a polyacrylate ( preparing a coating solution composed of a compound including an acrylate-based solute, which is at least one compound selected from the group consisting of polyacrylate, polyalkylacrylate and polymethacrylate; Coating a surface of the substrate with the coating solution; And Surface treatment method of the substrate comprising the step of drying the coated substrate. delete delete The method of claim 1, The acrylate-based solute is methyl methacrylate (Methylmethacrylate-MMA) surface treatment method of the substrate. The method of claim 1, The coating solution is trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane and (heptadeca-fluoro-1,1,2,2-tetrahydro-decyl) -1-trimethoxysilane At least one compound selected from the group consisting of a fluoro alkyl silane (fluoro alkyl silane) -based solute further comprising a surface treatment method. delete The method of claim 1, The acrylate-based solute is contained in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the fluorocarbon solvent. The method of claim 5, 0.1 to 5 parts by weight of the acrylate solute based on 100 parts by weight of the fluorocarbon solvent; And Surface treatment method of the substrate, characterized in that the fluoro alkylsilane-based solute is contained in 0.1 to 5 parts by weight. The method of claim 1, The substrate is a surface treatment method of the substrate, characterized in that made of at least one of polyimide and epoxy. The method of claim 1, The substrate is a surface treatment method of the substrate, characterized in that the porous. The method of claim 1, The coating step includes spin coating, roll coating, dip coating, screen coating, spray coating, screen printing and ink jet The surface treatment method of a substrate comprising the step performed using any one selected from the group consisting of). The method of claim 1, The coating step is a surface treatment method of the substrate comprising the step of coating on the substrate with a thickness of 0.1 to 1 ㎛. A fluorocarbon solvent and at least one compound selected from the group consisting of C ₂ F ₆ , C ₆ F ₁₄ , C ₇ F ₁₆ , C ₈ F ₁₈ , and C ₉ F ₂₀ , and a polyacrylate ( preparing a coating solution composed of a compound including an acrylate-based solute, which is at least one compound selected from the group consisting of polyacrylate, polyalkylacrylate and polymethacrylate; Coating a surface of a substrate with the coating solution; Drying the coated substrate; On the dried substrate is selected from the group consisting of silver (Ag), copper (Cu), nickel (Ni), gold (Au), platinum (Pt), palladium (Pd), iron (Fe) and alloys thereof Forming a wire with a conductive ink including at least one metal nanoparticle; And Method of manufacturing a substrate comprising the step of heat-treating the substrate. delete The method of claim 13, The wiring forming step is performed by discharging the conductive ink by an inkjet method. The method of claim 13, The width | variety of the said wiring is 20-100 micrometers, The manufacturing method of the board characterized by the above-mentioned. The method of claim 13, The heat treatment step is a method for producing a substrate, characterized in that performed for 0.5 to 2 hours at a temperature of 150 to 250 ℃.

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