KR20120117545A - Transparent electrode and method thereof - Google Patents

Abstract

PURPOSE: A transparent electrode and a manufacturing method thereof are provided to minimize generation of a crack or deformation caused by flexion, thereby maintaining conductivity and resistibility. CONSTITUTION: A transparent electrode includes a substrate(10), a pattern unit(210), a transparent conductive oxide film(30), and a base layer. The pattern unit is formed on the substrate. The transparent conductive oxide film is formed on the substrate which the pattern unit is formed. Before the pattern unit is formed, the base layer is formed on the substrate.

Description

Transparent Electrode and Method for Manufacturing the Same {Transparent Electrode And Method Thereof}

The present invention relates to a transparent electrode and a method for manufacturing the same, and more particularly, to a flexible transparent electrode and a method for manufacturing the same that can improve durability because it can maintain conductivity and resistance by minimizing cracks and deformation even after bending or bending will be.

Transparent electrodes are optically transparent and have good electrical conductivity, and are widely used as electrodes of optical devices such as touch pads or touch window electrodes, solar cell electrodes, liquid crystal displays (LCDs), and OLEDs.

In general, a polymer substrate is used to provide flexibility to the transparent electrode, and as an electrode material, an oxide-based inorganic material such as indium tin oxide (ITO), a conductive polymer material, graphene, carbon nanotube (CNT), etc. Is being used.

Among the electrode materials as described above, materials such as conductive polymers, graphene, carbon nanotubes, etc. have good flexibility, but have poor conductivity or transparency.

Therefore, oxide-based inorganic materials having excellent conductivity and transparency are widely used as transparent electrodes.

However, the conventional oxide-based inorganic material is excellent in transparency and conductivity, but due to the characteristics of the inorganic material is brittle, not ductile, there is a problem that it is difficult to secure flexibility by forming cracks when bent or bent, due to cracks or dislocations Due to the gradually increasing the resistance there was a problem that the electrical conductivity is significantly reduced.

An object of the present invention to solve the above problems is to provide a transparent electrode and a method of manufacturing the same that can maintain the conductivity and resistance by minimizing the occurrence of cracks or deformation when bent or bent.

In order to achieve the above object, the transparent electrode according to the present invention is characterized by including a substrate, a pattern portion formed on the substrate, and a transparent conductive oxide film formed on the substrate on which the pattern portion is formed.

The base layer is further formed on the substrate before the pattern portion is formed.

The pattern portion may be composed of an irregular pattern formed by etching the surface of the substrate, or may be composed of a pattern layer formed separately on the substrate.

The pattern layer is formed in a three-dimensional structure including a plurality of patterns formed at regular intervals or irregularly on the substrate.

In addition, the pattern layer is formed of an irregular pattern structure formed by etching the base layer after the base layer having a uniform thickness is formed, or includes a plurality of patterns formed at regular intervals or irregularly on the base layer of uniform thickness. It is characterized in that formed in a three-dimensional structure.

The transparent conductive oxide film is formed of at least one oxide selected from ITO, FTO, AZO, IZO, GZO, ATO, and NTO.

In addition, the three-dimensional structure is characterized in that any one selected from a cone, a truncated cone, a polygonal pyramid, a polygonal truncated cone, a cylinder, a polyhedron, an irregular shape in a unit pattern.

The pattern layer and the base layer are formed of a transparent polymer, characterized in that formed with at least one stage of the coating layer.

In addition, the transparent conductive oxide film is characterized in that it further comprises an overcoat layer.

The overcoat layer is formed of any one selected from an oxide film, a nitride film, and an organic film of a transparent material.

On the other hand, the method for manufacturing a transparent electrode according to the invention is characterized in that it comprises the step of forming a pattern portion on the substrate and the step of forming a transparent conductive oxide film on the substrate on which the pattern portion is formed.

And forming a base layer on the substrate before forming the pattern portion.

In addition, the forming of the pattern portion may be formed as a separate pattern layer using an irregular pattern structure or a transparent polymer formed by etching the substrate.

The pattern layer may be formed by forming an irregular pattern structure formed by etching the base layer or forming a three-dimensional structure including a plurality of patterns formed at regular intervals or irregularly on the uniform thickness of the base layer. Characterized in that.

And the three-dimensional structure is characterized by being formed by a method selected from lithography, imprint lithography, photolithography, silkscreen, offset printing, gravure, pad printing, flexo, transfer method.

The method may further include forming an overcoat layer on the transparent conductive oxide film.

The overcoat layer is formed of any one selected from an oxide film, a nitride film and an organic film of a transparent material.

As described above, the transparent electrode and the method of manufacturing the same according to the present invention can maintain the conductivity and resistance by minimizing the occurrence of cracks or deformation when bent or bent, thereby greatly improving the flexibility of the transparent electrode using the transparent conductive oxide film. have.

In addition, when the projection of the fine pattern structure according to the present invention is diffusely reflected light is applied to the LCD device using a backlight, an excellent effect to increase the light extraction efficiency occurs.

1 is a cross-sectional view schematically showing a transparent electrode according to a first embodiment of the present invention, Figure 2 is a perspective view of the pattern of FIG.
3 is a cross-sectional view showing that the hard coating layer is further included in the first embodiment.
4 is a cross-sectional view schematically illustrating a transparent electrode according to a second exemplary embodiment of the present invention, and FIG. 5 is a perspective view schematically illustrating various three-dimensional structures of the pattern layer of FIG. 1.
6 is a cross-sectional view showing that the hard coating layer is further included in the second embodiment.
FIG. 7 illustrates a structure in which an irregular pattern is formed by etching on a surface of a base layer having a uniform thickness in a variation of the second embodiment of the present invention.
FIG. 8 illustrates that a pattern layer is formed in a three-dimensional structure on a base layer having a uniform thickness in another variation of the second embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The transparent electrode according to the present invention may include a substrate, a pattern portion formed on the substrate, and a transparent conductive oxide film formed on the substrate on which the pattern portion is formed.

Here, the pattern portion may be composed of a pattern formed directly on the surface of the substrate by etching the substrate, it may be composed of a pattern formed by a separate coating layer formed on the substrate.

1 is a schematic view of a transparent electrode according to a first embodiment of the present invention, Figure 2 is a perspective view schematically showing a pattern portion of FIG.

1 and 2, the transparent electrode according to the first embodiment of the present invention includes a pattern 210 formed by etching the substrate 10 and the substrate surface and a transparent conductive oxide film 30 formed on the patterned substrate. It may be configured to include).

The substrate 10 may be formed of a flexible material such as polyethylene terephthalate (PET), polyether sulfone (PES), polyethylene naphthalate (PEN), or polyimide (PI).

Therefore, the substrate 10 has some flexibility, and the surface area contacted when forming the transparent conductive thin film is increased due to the pattern formed on the surface of the substrate 10, and the bending property is improved, so that cracking occurs when bending or bending is applied. It is possible to suppress and maintain good resistance.

In addition, the hard coating layer 110 may be further formed on the substrate as shown in FIG. 3, and may be formed by applying a hard coating solution on the substrate 10 and UV curing. When the hard coating layer 110 is formed as described above, the substrate on which the hard coating layer 110 is formed may be etched to form the pattern 210, and then the transparent conductive oxide layer 30 may be formed.

In addition, the transparent conductive oxide film 30 may be a crystalline transparent conductive oxide film and an amorphous transparent conductive oxide film, preferably, ITO (Tin doped Indium Oxide), FTO (Fluor doped Tin Oxide), AZO (Aluminium doped Zinc Oxide) ), IZO (ZnO doped Indium Oxide), GZO (Galium doped Zinc Oxide), ATO (Aluminium doped Zinc Oxide) and NTO (Niobium doped Titanium Oxide) may be formed of at least one oxide selected from the group.

4 is a cross-sectional view schematically illustrating a transparent electrode according to a second exemplary embodiment of the present invention, and FIG. 5 is a perspective view illustrating various shapes of the pattern layer of FIG. 4.

4 and 5, the transparent electrode according to the present invention includes a transparent conductive oxide film formed on the substrate 10, the pattern layer 220 formed on the substrate, and the substrate 10 on which the pattern layer 220 is formed. 30).

6, after the hard coating layer 110 is formed on the substrate 10, the pattern layer 220 and the transparent conductive oxide layer 30 may be formed.

In the first embodiment, the surface of the substrate is etched to form a pattern, and when the transparent conductive oxide film is formed, the warpage or bending characteristics are improved by increasing the surface area due to the pattern, but the material of the substrate is a hard material because it is a hard material Since is continuously stacked may have a limit in improving the bending or bending characteristics.

Accordingly, by forming a soft and elastic pattern layer between the hard material substrate and the transparent conductive oxide film, as in the second embodiment, the pattern layer plays an effect of buffering the surface area of the transparent conductive oxide film and a buffering role. The bending characteristics can be further improved.

The pattern layer 220 may have a unit pattern having a gear structure, a three-dimensional solid structure, or an irregular three-dimensional structure, and the unit pattern may be formed in any shape that can widen the surface area when the transparent conductive oxide film is formed. Likewise, it can be formed into various shapes such as cones, truncated cones, polygonal pyramids, polygonal truncated cones, cylinders, polyhedrons, and irregular shapes.

In addition, in consideration of the radius of curvature when bent or bent, it is preferable to form the interval between the height and the projection of each unit pattern to 1mm or less, preferably 500um or less.

And the pattern layer 30 may be formed of the transparent polymer, polymethacrylates (polymethacrylates), polyacrylics (polyacrylics), polyacrylates (polyacrylates), polyacrylonitrile (polyacryloniriles), polyvinyl alcohol ( polyvinyl alcohols, polyesters, polyester naphthalates and polycarbonates, phenolics, or cresol-formaldehyde, polystyrenes, polyvinyltoluene polyvinyltoluene, polyvinylxylene, polyimides, polyamides, polyamideimides, polyetherimides, polysulfides, polysulfones, Polyphenylenes, polyphenyl ethers, polyurethane (PU), epoxy, polyolefins, poly Polymethylpentene, and cyclic olefins, acrylonitrile-butadiene-styrene copolymers (ABS), cellulosics, silicones and other polymers Silicones (eg, polysilsesquioxanes and polysilanes, polyvinyl chloride (PVC), polyacetates, polynorbornenes, polynorbornenes, synthetic rubbers) synthetic rubbers (e.g., EPR, SBR, EPDM), and fluoropolymers (e.g., polyvinylidene fluoride, polytetrafluoreoethylene (TFE), or polyhexafluoropropylene ), Fluoro-olefin and hydrocarbon olefin and amorphous fluorocarbon polymers or copolymers (e.g., CYTOP from Asahi Glass or Tef from Dupont) lon AF), but is not limited thereto.

In addition, the pattern layer is formed on the entire substrate as shown in Figure 7, the uniform base layer 230 of the transparent polymer as described above, and then etching the base layer to form an irregular pattern 231 and then a transparent conductive oxide film ( 30).

Alternatively, the transparent conductive oxide film 30 may be formed after the pattern layer 242 is formed on the uniform base layer 241 as in FIG. 8 as shown in FIG. 8.

The base layers 230 and 241 may be formed of the same material as the pattern layers 241 and 220.

In all embodiments according to the present invention, the transparent conductive oxide film 30 may further include an overcoat layer that protects the transparent conductive oxide film and provides a refractive index, as shown in FIG. 3.

Hereinafter, a method of manufacturing a transparent electrode according to a preferred embodiment of the present invention will be described with reference to the second embodiment (FIG. 6).

First, the hard coating layer 110 is formed on the substrate 10.

The hard coating layer may be an acrylic hard coating (H / C) liquid, it may be composed of a single layer of 2-5um thickness. The hard coating solution may be applied onto a substrate and then UV cured to form a hard coating layer.

The pattern layer 220 is formed on the hard coating layer 110.

The pattern layer 220 may be formed by lithography, imprint lithography, photolithography, silk screen, offset printing, gravure, pad printing, flexographic, or the like.

In addition, the release film having a pattern formed on the upper surface of the substrate may be formed by a transfer method formed by stamping by heat or pressure.

When the coating layer 220 is formed as described above, a transparent conductive oxide film 30 is formed on the hard coating layer 110.

In addition, while forming the hard coating layer 110, the coating layer 220 may be formed at the same time.

Here, the transparent conductive oxide film 30 may be formed by depositing a transparent conductive oxide on the hard coating layer by a sputtering method.

An overcoat layer may be further formed to protect the transparent conductive oxide layer 30 and provide a refractive index.

The overcoat layer may be formed of a transparent material in the same manner as the coating layer in order to prevent the coating layer from being visually recognized, and may be formed by coating or depositing an oxide film, a nitride film, an organic film, or the like.

Due to the overcoat layer as described above, the transmittance can be adjusted to improve visibility, and the effect of preventing the degree of rapid change in resistance during bending while protecting the transparent conductive film.

Hereinafter, specific test results for the transparent electrode according to the present invention will be described.

≪ Example 1 >

Sample 1: PET (188um) + hard coating solution / UV curing.

Sample 2: Pattern layer formation by PET (188um) + hard coating solution / UV curing + imprint lithography method.

After depositing ITO on Samples 1 and 2, a 10mm × 50mm sample was made, and a bending test (bending test) was performed to measure resistance change while bending 10 times.

The bending test results as described above are shown in Table 1 below.

TABLE 1

Here, φ represents the degree of bending for the sample.

As can be seen from Table 1, sample 1 maintains resistance up to φ25, but rapid resistance change occurs and crack occurs at φ15, while sample 2 maintains resistance up to φ25 and resistance change occurs at φ15. However, it can be seen that the resistance change is very small compared to Sample 1.

<Example 2>

Sample 3: PET (188um) + hard coating solution / UV curing.

Sample 4: Pattern layer formation by PET (188um) + hard coating liquid / UV hardening + imprint lithography method.

After depositing ITO on Samples 1 and 2, a 10 mm x 50 mm sample was made, and the resistance change was measured while bending at φ 5 having a very high flexibility.

The reproducibility test results as described above are shown in Table 2.

<Table 2>

As can be seen from Table 2, Sample 1 and Sample 2 show a difference of 24 to 65 times in the retention of resistance values, and may vary slightly depending on the hardening conditions of the hard coating layer and the implementation of coating layer formation. It can be seen that Sample 2 shows a significant difference between Sample 1 and the resistance holding value. This means that the flexibility of Sample 2 is greatly improved compared to Sample 1.

<Example 3>

Sample 5: conventional ITO film-Nitto Denko ITO film (180um)

Sample 6: PET (188um) + hard coating solution / UV curing.

Sample 7: Pattern layer formation by PET (188um) + hard coating liquid / UV curing + imprint lithography method.

After depositing ITO on Samples 5, 6, and 7, a 10mm × 50mm sample was produced, and the change in resistance was measured while bending at φ5 having a very high flexibility.

The bending test results as described above are shown in Table 3.

<Table 3>

As can be seen from Table 3, it can be seen that Sample 7 has a very stable resistance retention compared to Samples 5 and 6.

<Example 4>

Sample 8: Pattern layer formation + ITO deposition by PET (188 um) + hard coating solution / UV curing + imprint lithography method.

Sample 9: Pattern layer formation + ITO deposition + overcoat layer formation by PET (188 um) + hard coating solution / UV curing + imprint lithography method.

After the sample 8 and the sample 9 to prepare a 10mm × 50mm sample, the bending resistance was measured 10 times at a very large φ 5 and the resistance change was measured.

The bending test results as described above are shown in Table 4.

TABLE 4

As can be seen from Table 4, it can be seen that sample 9 is more stable in resistance retention than sample 8. Therefore, it can be seen that the flexibility is improved when the overcoat layer is formed than when the overcoat layer is not formed.

Through the above embodiment, the transparent electrode formed with the coating layer according to the present invention can be seen that the resistance maintenance is very stable compared to the transparent electrode without forming the conventional coating layer, thereby confirming that the flexibility is greatly improved.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

10: substrate 210: pattern
231, 241: base layer 220, 242: pattern layer
30: transparent conductive oxide film

Claims (17)

A substrate;
A pattern portion formed on the substrate;
And a transparent conductive oxide film formed on the substrate on which the pattern portion is formed.
The method of claim 1,
Before the pattern portion is formed
A transparent electrode, characterized in that the base layer is further formed on the substrate.
The method of claim 1,
The pattern portion
The substrate comprises an irregular pattern formed by etching the surface of the substrate, or a transparent electrode comprising a pattern layer formed separately on the substrate.
The method of claim 3, wherein
The pattern layer is
Transparent electrode, characterized in that formed in a three-dimensional structure including a plurality of patterns formed at regular intervals or irregularly on the substrate.
The method of claim 3, wherein
The pattern layer is
After forming the base layer having a uniform thickness is formed in an irregular pattern structure formed by etching the base layer, or formed in a three-dimensional structure including a plurality of patterns formed at regular intervals or irregularly on the uniform thickness base layer A transparent electrode characterized by the above-mentioned.
The method of claim 1,
The transparent conductive oxide film
Transparent electrode, characterized in that formed of at least one oxide selected from ITO, FTO, AZO, IZO, GZO, ATO, NTO.
The method according to claim 3 or 5,
The three-dimensional structure
Transparent electrode, characterized in that formed in the unit pattern of any one selected from cone, truncated cone, polygonal pyramid, polygonal truncated cone, cylinder, polyhedron, irregular shape.
The method according to any one of claims 3 to 5,
The pattern layer and the base layer
A transparent electrode formed of a transparent polymer and formed of at least one coating layer.
The method of claim 1,
The transparent electrode further comprises an overcoat layer on the transparent conductive oxide film.
The method of claim 9,
The overcoat layer
Transparent electrode, characterized in that formed of any one selected from an oxide film, a nitride film, an organic film of a transparent material.
Forming a pattern portion on the substrate;
Forming a transparent conductive oxide film on the substrate on which the pattern portion is formed.
12. The method of claim 11,
Before forming the pattern portion
Forming a base layer on a substrate further comprising the method of manufacturing a transparent electrode.
12. The method of claim 11,
Forming the pattern portion
Method for forming a transparent electrode, characterized in that formed in a separate pattern layer using an irregular pattern structure or a transparent polymer formed by etching the substrate.
13. The method of claim 12,
Formation of the pattern layer is
Forming a three-dimensional structure including a plurality of patterns formed at a predetermined interval or irregularly on the base layer having a uniform thickness or formed in an irregular pattern structure formed by etching the base layer. electrode.
The method of claim 14,
The three-dimensional structure is
A method for manufacturing a transparent electrode, characterized in that formed by a method selected from lithography, imprint lithography, photolithography, silk screen, offset printing, gravure, pad printing, flexographic, transfer method.
12. The method of claim 11,
On the transparent conductive oxide film
Forming an overcoat layer further comprises a transparent electrode manufacturing method.
17. The method of claim 16,
The overcoat layer
Transparent electrode manufacturing method characterized in that formed of any one selected from oxide film, nitride film, organic film of a transparent material.

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