KR101076423B1 - Etch Resist and Method and Apparatus for Fabricating Flat Panel Display Using The Same - Google Patents

Abstract

The present invention relates to an etch resist that eliminates the need for a photo mask and reduces material waste, and a method and apparatus for manufacturing a flat panel display device using the same.

The etch resist is molded by contact with a soft mold and exposure of light and includes a liquid polymer precursor, a photocurable polymer and a photoinitiator.

Description

Etch Resist and Method and Apparatus for Manufacturing Flat Panel Display Using the Same {Etch Resist and Method and Apparatus for Fabricating Flat Panel Display Using The Same}             

1 is a perspective view showing an active matrix type liquid crystal display device.

2 is a view showing a method of manufacturing a flat panel display device according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a movement of an etch resist solution when the soft mold illustrated in FIG. 2 contacts a substrate.

4 is a cross-sectional view showing a bubble generated during the process of FIG. 2 and a pattern defect of an etch resist generated due to the bubble.

5 is a graph showing a relationship between an etch resist and an opening region.

6A is a cross-sectional view illustrating a residual film remaining between neighboring etch sheet patterns.

6B is a cross-sectional view illustrating an optimal state in which a residual film does not remain between neighboring etch resist patterns.

7 is a cross-sectional view showing the height of the etch resist and the intaglio pattern height of the soft mold.                 

8 is a photograph showing an experimental result in which the residual film remains above the optimum height of the etch resist.

9 is a photograph showing an experimental result without a residual film above the optimum height of the etch resist.

10A to 10C are photographs of experimental results showing a metal thin film pattern formed on a substrate when the etch resist pattern shown in FIG. 9 is used as a mask and the metal thin film under the etch resist pattern is etched.

<Description of Symbols for Main Parts of Drawings>

11, 17: polarizing plate 12, 16, 31: glass substrate

13 color filter 14 common electrode

15 liquid crystal layer 18 gate line

19: data line 20: thin film transistor

21 pixel electrode 22 color filter substrate

32a, 32b: thin film 33a, 33b: etch resist

34: soft mold 41: bubble

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel display device, and in particular, to an etch resist which eliminates the need for a photo mask and reduces material waste, and a method and apparatus for manufacturing the flat panel display device using the same.

In today's information society, display elements are more important than ever as visual information transfer media. Cathode ray tubes or cathode ray tubes, which are currently mainstream, have problems with weight and volume.

The flat panel display device includes a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electroluminescence (EL). Most are commercially available and commercially available.

Liquid crystal display devices can meet the trend of light and short and short of electronic products and mass production is improving, and are rapidly replacing cathode ray tubes in many applications.

In particular, an active matrix type liquid crystal display device that drives a liquid crystal cell using a thin film transistor (hereinafter referred to as "TFT") has the advantages of excellent image quality and low power consumption, and secures the latest mass production technology. As a result of research and development, it is rapidly developing into larger size and higher resolution.

The active matrix type liquid crystal display device includes a color filter substrate 22 and a TFT array substrate 23 bonded together with the liquid crystal layer 15 interposed therebetween as shown in FIG. 1. The liquid crystal display shown in FIG. 1 shows a part of the entire effective screen.

In the color filter substrate 22, a black matrix, a color filter 13, and a common electrode 14, which are not shown, are formed on the rear surface of the upper glass substrate 12. The polarizing plate 11 is attached on the front surface of the upper glass substrate 12. The color filter 13 includes color filters of red (R), green (G), and blue (B) colors to allow color display by transmitting visible light in a specific wavelength band.

In the TFT array substrate 23, the data lines 19 and the gate lines 18 cross each other on the front surface of the lower glass substrate 16, and TFTs 20 are formed at the intersections thereof. In addition, a pixel electrode 21 is formed in a cell region between the data line 19 and the gate line 18 on the front surface of the lower glass substrate 16. The TFT 20 drives the pixel electrode 21 by switching the data transfer path between the data line 19 and the pixel electrode 21 in response to the scanning signal from the gate line 18. The polarizing plate 17 is attached to the rear surface of the TFT array substrate 23.

The liquid crystal layer 15 adjusts the amount of light transmitted through the TFT array substrate 23 by the electric field applied thereto.

The polarizers 11 and 17 attached to the color filter substrate 22 and the TFT substrate 23 transmit light polarized in either direction, and their polarization directions when the liquid crystal 15 is in the 90 ° TN mode. Are orthogonal to each other.

An alignment film (not shown) is formed on the liquid crystal facing surfaces of the color filter substrate 22 and the array TFT substrate 23.

The manufacturing process for manufacturing the active matrix type liquid crystal display device is divided into substrate cleaning, substrate patterning process, alignment film formation / rubbing process, substrate bonding / liquid crystal injection process, mounting process, inspection process, repair process, etc. . In the substrate cleaning process, foreign substances contaminated on the substrate surface of the liquid crystal display device are removed with a cleaning liquid. The substrate patterning process is divided into a patterning process of a color filter substrate and a patterning process of a TFT array substrate. In the alignment film formation / rubbing process, an alignment film is applied to each of the color filter substrate and the TFT array substrate, and the alignment film is rubbed with a rubbing cloth or the like. In the substrate bonding / liquid crystal injection process, a color filter substrate and a TFT array substrate are bonded together using a sealant, a liquid crystal and a spacer are injected through the liquid crystal injection hole, and then the liquid crystal injection hole is sealed. In the mounting process, a tape carrier package (hereinafter referred to as "TCP") in which integrated circuits such as a gate drive integrated circuit and a data drive integrated circuit are mounted is connected to a pad portion on a substrate. Such a drive integrated circuit may be directly mounted on a substrate by a chip on glass (COG) method in addition to the tape automated bonding method using the aforementioned TCP. The inspection process includes an electrical inspection performed after signal wiring such as data lines and gate lines and pixel electrodes are formed on the TFT array substrate, and an electrical inspection and a visual inspection performed after the substrate bonding / liquid crystal injection process. The repair process restores the substrate that is determined to be repairable by the inspection process. Non-repairable substrates are discarded in the inspection process.

In the manufacturing method of most flat panel display devices including the liquid crystal display device, the thin film material deposited on the substrate is patterned by a photolithography process. Photolithography processes are generally a series of photolithography processes including the application of photoresist, mask alignment, exposure, development, etching and stripping processes. In the case where the target thin film to be patterned is used as a photosensitive organic material, the exposure process and the developing process may be omitted in the photolithography process.

However, such a photolithography process requires an expensive photomask and exposure equipment, and requires a long process time and waste of materials.

Accordingly, it is an object of the present invention to provide an etch resist and a method and apparatus for manufacturing a flat panel display device using the same, which eliminates the need for a photo mask and reduces material waste.

In order to achieve the above object, the etch resist according to the embodiment of the present invention is molded by contact with the soft mold and exposure of light and includes a liquid polymer precursor, a photocurable polymer and a photoinitiator.

The etch resist is 20 to 50wt% of the liquid polymer precursor; 40 to 60 wt% of the photocurable polymer; 1 to 10 wt% of the photoinitiator.

The liquid polymer precursor is hydrophilic.

The liquid polymer precursor includes liquid polyethylene glycol.

The photocurable polymer includes a liquid acrylate (acrylate).

The photoinitiator includes 2,2-dimethoxy-2phenylacetophenone.

The liquid polymer precursor has a molecular weight of 600 or less.

The opening region between the etch resist patterns formed by contact with the soft mold and exposure of light and the thickness of the etch resist are inversely related.

There is no residual film of the etch resist in the opening region.

The width of the opening region is within 0 μm to 1000 μm.

The dielectric constant of the etch resist is within 2.5 to 3.5.

A method of manufacturing a flat panel display device according to an embodiment of the present invention comprises the steps of applying an etch resist solution comprising a liquid polymer precursor, a photocurable polymer and a photoinitiator on a substrate; Pressing the soft mold onto the etch resist solution and irradiating light onto the etch resist solution to form an etch resist pattern on the substrate; Separating the soft mold from the etch resist pattern.

The substrate includes a thin film to which the etch resist solution is applied.

The manufacturing method of the flat panel display device may include etching the thin film using the etch resist pattern as a mask; The method may further include removing the etch resist pattern to leave the thin film pattern on the substrate.

An apparatus for manufacturing a flat panel display device according to an embodiment of the present invention includes a coating device for applying an etch resist solution containing a liquid polymer precursor, a photocurable polymer and a photoinitiator on a substrate; A soft mold pressed onto the etch resist solution; And an exposure apparatus for irradiating light onto the etch resist solution while the soft mold is pressed onto the etch resist solution.

The apparatus for manufacturing a flat panel display device may include: an etching apparatus for etching the thin film by using an etch resist pattern remaining on the substrate as a mask by pressing the soft mold and the exposure; A strip device for removing the etch resist pattern is further provided.

The flat panel display device is any one of a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electroluminescent device (EL).

Other objects and features of the present invention in addition to the above object will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 2 to 6.

Referring to FIG. 2, in the method of manufacturing a flat panel display device according to an exemplary embodiment of the present invention, an etch resist solution 33a is formed on a glass substrate 31 on which a thin film 32a of a pixel array is formed using a coating apparatus. ) Etch resist coating step of applying, patterning process of etch resist solution 33a using soft mold 34, etching process for patterning thin film 32a, strip removing etch resist pattern 33b with strip solution Process, and an inspection process for the thin film pattern 32b.

The thin film 32a of the pixel array formed on the glass substrate 31 is a basic material used as a metal pattern, an organic pattern, and an inorganic pattern present in the pixel array of the flat panel display element. It is formed on (31).

The etch resist solution 33a is a material having heat resistance and chemical resistance. After the etch resist solution 33a is patterned with the etch resist pattern 33b, the etch resist pattern 33b serves as a mask that allows the thin film 32a to be selectively patterned in the etching process of the thin film 32a. Will be

The soft mold 34 is made of relatively high elastic polydimethylsiloxane (PDMS), polyurethane, cross-linked Novolac Resin, and the like on the glass substrate 31. An intaglio pattern 34a corresponding to the pattern to be formed is formed. After the soft mold 34 is aligned on the etch resist solution 33a, the soft mold 34 is pressurized to the etch resist solution 33a only at a pressure such that contact with the thin film 32a is possible, that is, at its own weight. At the same time, ultraviolet light (UV) of 350 nm to 370 nm is transmitted through the soft mold 34 to the etch resist solution 33a by the exposure apparatus, or transmitted through the glass substrate 31 and the thin film 32a to expose the etch resist solution 33a. Is investigated. Then, the etch resist solution 33a is formed by the capillary force generated by the pressure between the soft mold 34 and the glass substrate 31 and the repulsion force between the soft mold 34 and the etch resist solution 32a. As shown in FIG. 3, the inside of the groove 34a of the soft mold 34 is moved. At the same time, as the polymer network is formed in the etch resist solution 33a by the photopolymerization reaction of the etch resist solution 33a, the etch resist solution 33a isolated in the intaglio pattern 34a of the soft mold 34 is solidified. As a result, an etch resist pattern 33b is formed on the thin film 32a in an inverted transfer form of the intaglio pattern 34a formed in the soft mold 34.

After the inspection of the etch resist pattern 33b is performed, the soft mold 34 and the glass substrate 31 are separated. A wet etching process using a wet etching apparatus or a dry etching process using a dry etching apparatus is performed. At this time, since the etch resist pattern 33b serves as a mask, only the thin film 32a positioned below the etch resist pattern 33b remains on the glass substrate 31 and the other thin films 32a are removed. Subsequently, the etch resist pattern 33b is removed by a stripping process, and defects of the thin film pattern 32b are determined by electrical and optical inspection of the thin film pattern 32b.

On the other hand, when the etch resist pattern 33b is not used as a sacrificial layer but used as an insulator pattern that remains permanently on the substrate, the etch resist pattern 33b remains on the substrate 31 or the thin film 32a. In this case, the etching process of the thin film 32a and the strip process of the etch resist pattern 33b are omitted.

The soft mold 34 is separated from the glass substrate 31 and then washed with ultraviolet (UV) and ozone (O ₃ ), and then re-injected into another patterning process of the thin film 32a.

However, when a volatile solvent in the etch resist solution 33a is added in the patterning process of the etch resist, the soft mold 34 and the etch resist solution in the contact process of the soft mold 34 and the etch resist solution 33a ( Bubbles may be generated as the air between 33a) is trapped, and air bubbles may be generated by vaporization of the volatile solvent in the etch resist solution 33a. As shown in FIG. 4, the bubbles 41 increase and agglomerate in the pressure and baking process according to the pressure of the soft mold 34, and the bubbles act as a cause of depression or loss of the etch resist pattern 33b. These bubbles are known to have been generated in a number of experiments, even at room temperature. Accordingly, there is a need for a method capable of minimizing bubbles generated in the etch resist solution 33a or generated during the patterning process of the etch resist solution 33a.

In order to prevent unwanted etch resist residual film from remaining in the patterning process of the etch resist solution 33a, a condition required for the etch resist solution 33a is that the surface of the soft mold 34 in contact with it has a high repulsive property. It should be visible, capable of firing by reaction with ultraviolet (UV), and should have low viscosity. For example, if the soft mold 34 is made of hydrophobic polydimethylsiloxane (PDMS), the etch resist solution is preferably selected as a hydrophilic material. In addition, in order to prevent unwanted etch resist residual film from remaining in the patterning process of the etch resist solution 33a, the adhesive force between the soft mold 34 and the etch resist solution 33a lowers the fluidity of the etch resist solution 33a. It is desirable to make the adhesion as small as possible.

In order to satisfy the conditions of the etch resist solution 33a, the etch resist solution 33a according to the present invention is a liquid polymer precursor (prepolymer) having a high repulsion property with the soft mold 34, as shown in Table 1 below, It contains photocurable polymers and trace catalysts and does not contain volatile solvents. The liquid polymer precursor has a molecular weight of preferably 600 or less, and for example, may be used as polyethylene glycol having hydrophilicity. This liquid polymer precursor imparts a repulsive force to the etch resist solution 33a with respect to the soft mold 34 upon contact with the soft mold 34 to facilitate the movement of the etch resist solution 33a. The photocurable polymer may be used as a liquid acrylate or liquid Novolac resin material. The photocurable polymer increases the adhesion of the etch resist pattern 33b to the substrate 31, maintains the pattern shape, and enhances the chemical resistance of the etch resist pattern 33b to the etchant in the etching process. The catalyst can be used as 2,2-dimethoxy-2phenylacetophenone as a photoinitiator to induce the photopolymerization reaction of the liquid polymer precursor and the crosslinking agent.

Liquid Polymer Precursors Photocurable polymer catalyst Yes Liquid Polyetylene glycol Liquid acrylate 2,2-dimethoxy-2phenylacetophenone Composition ratio 20-50 wt% 40 to 80 wt% 1-10 wt%

FIG. 5 shows the relationship between the etch resist solution 33a having the composition shown in Table 1 and the maximum possible opening area without the residual film thickness of the etch resist solution 33a. The maximum possible opening area without the residual film is the etch resist patterns 33b without the etch resist residual film 33c remaining between the adjacent etch resist patterns 33b as shown in FIG. 6A and without the etch resist residual film 33c as shown in FIG. 6B. ) Is the maximum area between. As can be seen in FIG. 5, the maximum opening area As possible without the residual film is inversely proportional to the thickness d of the etch resist solution 33a. That is, the smaller the thickness d of the etch resist solution 33a is, the larger the size of the opening region As is. Therefore, the thickness d of the etch resist solution 33a can be adjusted to widen the interval between the etch resist patterns 33b.

In consideration of the intaglio pattern 34a of the soft mold 34, the optimum thickness d of the etch resist solution 33a to prevent the remaining etch resist film 33c from remaining between the adjacent etch resist patterns 33b is as follows. Equation 1 should be satisfied. FIG. 7 is a diagram for defining respective variables in Equation 1. FIG.

7, 'd' is the thickness of the etch resist solution 33a, 'h' is the height or depth of the intaglio pattern 34a formed on the soft mold 34, and 'A _L ' is the etch resist pattern 33a. Area, 'A _S ' represents the maximum opening area As.

In order to verify the etch resist according to the present invention, the etch resist solution 33a is made of 20wt% polyethylene glycol, 75wt% acrylate and 5wt% 2,2-dimethoxy-2phenylacetophenone. An experiment was conducted in which the solution was made of a mixed solution, the soft mold 34 was pressed against the etch resist solution 33a, and the ultraviolet exposure was carried out. Here, the ultraviolet wavelength was 365 nm and the exposure time was 1 to 30 seconds. According to the experimental result, when the thickness of the etch resist solution 33a becomes thicker than the optimum thickness d defined in Equation 1, a residual film is left between the etch resist patterns 33b as shown in FIG. When the thickness of the solution 33a is less than or equal to the optimum thickness d defined in Equation 1, it may be confirmed that no residual film remains between the etch resist patterns 33b as shown in FIG. 9.

As a result of this experiment, it was confirmed that the maximum possible width of the opening area without the residual film between the etch resist patterns 33b was 500 μm or more. When the etch resist solution 33a shown in Table 1 is used, the maximum possible width of the opening area without a residual film is within 0 μm to 1000 μm.

10A through 10C illustrate a metal thin film pattern formed on the substrate 31 when the etch resist pattern 33 b as shown in FIG. 9 is used as a mask and the metal thin film 32 a under the etch resist pattern 33 b is etched. 32b) is an experimental result. Here, the material of the metal thin film 33a was selected as AlNd. In FIGS. 10A to 10C, the wiring width of the metal thin film 33a is 20 μm. The maximum possible width of the opening area without remaining film between the etch resist patterns 33b is 300 μm in FIG. 10A, 400 μm in FIG. 10B, and 500 μm in FIG. 10C.

A method and apparatus for manufacturing a flat panel display device according to the present invention can be applied to flat panel display devices or semiconductor devices such as liquid crystal display (LCD), field emission display (FED), plasma display panel (PDP) and electroluminescent device (EL). It can be applied to a process for patterning the included electrode layer, organic material layer, semiconductor layer and inorganic layer. In addition, the etch resist according to the present invention may be used as an insulator layer or barrier material of the flat panel display device or the semiconductor device. In this case, the dielectric constant of the insulator layer or partition wall made of an etch resist becomes between 2.5 and 3.5 by the composition of Table 1. On the other hand, benzocyclobutene (Benzocyclobutene, BCB), which has been used as an organic insulating layer or barrier material, has a dielectric constant of approximately 2.6 and photo-acrylate has a dielectric constant of approximately 3.3.

As described above, since the etch resist according to the present invention does not contain a volatile solvent, the generation of bubbles can be minimized, and since the etch resist is in contact with the soft mold and the etch resist since the polymer precursor has a large repulsive force with the soft mold as a main component. By increasing the fluidity of the can be minimized to leave the residual etch resist film. The method and apparatus for manufacturing a flat panel display device using such an etch resist can be applied to all kinds of flat panel display devices, and can use an etch resist as an insulating layer or a partition material of the flat panel display device. The etch resist or the thin film below it can be patterned and there is little material waste of the etch resist.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

Claims (32)

An etch resist formed by contact with a soft mold and exposure to light, comprising 20 to 50 wt% of a liquid polymer precursor, 40 to 60 wt% of a photocurable polymer, and 1 to 10 wt% of a photoinitiator. delete The method of claim 1, The liquid polymer precursor, Etch resist, characterized in that the hydrophilic. The method of claim 1, The liquid polymer precursor, Etch resist, characterized in that it comprises a liquid polyethylene glycol (Polyethylene glycol). The method of claim 1, The photocurable polymer, Etch resist, characterized in that it comprises at least one of a liquid acrylate (acrylate) and a liquid novolac resin (Novolac resin). The method of claim 1, The photoinitiator, An etch resist comprising 2,2-dimethoxy-2phenylacetophenone. The method of claim 1, The liquid polymer precursor, Etch resist, characterized in that the molecular weight is 600 or less. delete The method of claim 1, And the remaining film of the etch resist is not present in the opening region between the etch resist patterns formed by contact with the soft mold and exposure of light. The method of claim 9, An etch resist, characterized in that the width of the opening region is within 1μm to 1000μm. The method of claim 1, Etch resist, characterized in that the dielectric constant of the etch resist is within 2.5 to 3.5. Applying an etch resist solution comprising 20 to 50 wt% of a liquid polymer precursor, 40 to 60 wt% of a photocurable polymer, and 1 to 10 wt% of a photoinitiator on a substrate; Pressing the soft mold onto the etch resist solution and irradiating light onto the etch resist solution to form an etch resist pattern on the substrate; And separating the soft mold from the etch resist pattern. 13. The method of claim 12, Wherein: And a thin film on which the etch resist solution is applied. The method of claim 13, Etching the thin film using the etch resist pattern as a mask; And removing the etch resist pattern to leave the thin film pattern on the substrate. delete 13. The method of claim 12, The liquid polymer precursor, A method of manufacturing a flat panel display element, characterized in that it is hydrophilic. 13. The method of claim 12, The liquid polymer precursor, Liquid polyethylene glycol; The photocurable polymer comprises at least one of a liquid acrylate and a liquid Novolac resin; The photoinitiator is a manufacturing method of a flat panel display device comprising 2,2-dimethoxy-2phenylacetophenone. Claim 18 was abandoned upon payment of a set-up fee. The method of claim 13, The flat panel display device may be any one of a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electroluminescent device (EL). 13. The method of claim 12, Applying the etch resist solution on a substrate, And applying the etch resist solution on the substrate in a thickness in inverse proportion to an opening region between adjacent etch resist patterns. The method of claim 19, And a residual film of the etch resist pattern is not formed in the opening region. Claim 21 has been abandoned due to the setting registration fee. The method of claim 19, A width of the opening area is within 1 μm to 1000 μm. Claim 22 is abandoned in setting registration fee. 13. The method of claim 12, And a dielectric constant of the etch resist solution is within 2.5 to 3.5. An application apparatus for applying an etch resist solution comprising 20 to 50 wt% of a liquid polymer precursor, 40 to 60 wt% of a photocurable polymer, and 1 to 10 wt% of a photoinitiator; A soft mold pressed onto the etch resist solution; And an exposure apparatus for irradiating light to the etch resist solution while the soft mold is pressed onto the etch resist solution. The method of claim 23, wherein And a thin film on which the etch resist solution is applied is formed on the substrate. The method of claim 24, An etching apparatus for etching the thin film by using an etch resist pattern remaining on the substrate by pressing the soft mold and the exposure; And a strip device for removing the etch resist pattern. delete The method of claim 23, wherein The liquid polymer precursor, Liquid polyethylene glycol; The photocurable polymer comprises at least one of a liquid acrylate and a liquid Novolac resin; The photoinitiator manufacturing apparatus for a flat panel display device comprising 2,2-dimethoxy-2phenylacetophenone. Claim 28 has been abandoned due to the set registration fee. The method of claim 23, wherein The flat panel display device is any one of a liquid crystal display (LCD), a field emission display device (FED), a plasma display panel (PDP) and an electroluminescent device (EL). The method of claim 25, And the coating device applies the etch resist solution on the substrate in a thickness in inverse proportion to an opening area between adjacent etch resist patterns. 30. The method of claim 29, And the remaining film of the etch resist pattern is not formed in the opening region. Claim 31 has been abandoned due to the setting registration fee. 30. The method of claim 29, A width of the opening area is within 1 μm to 1000 μm. Claim 32 is abandoned due to the set registration fee. The method of claim 23, wherein And a dielectric constant of the etch resist solution is within 2.5 to 3.5.

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