KR20070076287A - Manufacturing Method Of Liquid Crystal Display - Google Patents

Abstract

There is provided a method of manufacturing a liquid crystal display device which simplifies the manufacturing process and can solve the afterimage problem. The manufacturing method of the liquid crystal display device includes transferring a color filter resin filled in a printing groove of a printing plate onto an insulating substrate, and curing the color filter resin on the insulating substrate to complete a color filter.

Description

Method of manufacturing a liquid crystal display device

1A is a layout view of a liquid crystal display manufactured by a manufacturing method according to an embodiment of the present invention.

FIG. 1B is a cross-sectional view of the liquid crystal display of FIG. 1A taken along line Ib-Ib '. FIG.

FIG. 1D is a cross-sectional view of the liquid crystal display of FIG. 1A taken along line Ic-Ic ′. FIG.

FIG. 1D is a cross-sectional view of the liquid crystal display of FIG. 1A taken along the line Id-Id '.

FIG. 1E is a layout view illustrating a color filter of the liquid crystal display of FIG. 1A.

2A through 2E are cross-sectional views sequentially illustrating a method of manufacturing a color filter of a liquid crystal display according to an exemplary embodiment of the present invention.

3 is a cross-sectional view illustrating a manufacturing process of a liquid crystal display according to another exemplary embodiment of the present invention.

 (Explanation of symbols for the main parts of the drawing)

10: insulating substrate 22: gate line

24: gate line end 26: gate electrode

28: sustain electrode line 29: sustain electrode

30: gate insulating film 40: semiconductor layer

55, 56: ohmic contact layer 62: data line

65 source electrode 66 drain electrode

67: drain electrode extension 68: end of the data line

70: protective film 72: color filter

73: opening 74, 76, 78: contact hole

82: pixel electrode 86: auxiliary gate line end

88: end of auxiliary data line 90: common electrode

94: black matrix 96: insulating substrate

100: lower display panel 200: upper display panel

300: liquid crystal layer 410: printing plate

412: printing groove 420: resin supply unit

430: resin for color filters 440: blade

450: transfer roller 451: transfer sheet

510: cylindrical printing plate 512: printing groove

The present invention relates to a method for manufacturing a liquid crystal display, and more particularly, to a method for manufacturing a color filter included in a liquid crystal display.

Liquid crystal display is one of the most widely used flat panel displays. It consists of two substrates on which electrodes are formed and a liquid crystal layer interposed therebetween. The display device is applied to rearrange the liquid crystal molecules of the liquid crystal layer to control the amount of light transmitted.

In the liquid crystal display, a liquid crystal material having anisotropic dielectric constant is injected between an upper display panel on which a common electrode is formed and a lower display panel on which a thin film transistor and a pixel electrode are formed, and different potentials are applied to the pixel electrode and the common electrode. By changing the molecular arrangement of the liquid crystal material by adjusting the intensity of the electric field formed in the liquid crystal material, thereby controlling the amount of light transmitted through the transparent insulating substrate to display a desired image.

In order to increase the aperture ratio of the liquid crystal display, a liquid crystal display having a color filter on array (COA) structure for forming a color filter on the thin film transistor has been developed. In addition, recently, by forming a thick color filter, a process of forming a passivation layer in a thin film transistor manufacturing is skipped, and thus, a study for improving yield and optical characteristics is underway.

However, in the case of the liquid crystal display of the COA structure, the liquid crystal layer is contaminated by out-gas emitted from the color filter exposed by the pixel electrode, and the movement of the liquid crystal molecules forming the liquid crystal layer is slowed down, resulting in afterimages. There is a problem.

An object of the present invention is to provide a method of manufacturing a liquid crystal display device which can simplify a manufacturing process and solve an afterimage problem.

Technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, the method including transferring a resin for a color filter filled in a printing groove of a printing plate onto an insulating substrate, and the color on the insulating substrate. Curing the resin for the filter to complete the color filter.

Specific details of other embodiments are included in the detailed description and the drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and only the embodiments make the disclosure of the present invention complete, and the general knowledge in the art to which the present invention belongs. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, a method of manufacturing a liquid crystal display according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1A is a layout view of a liquid crystal display manufactured by a manufacturing method according to an exemplary embodiment of the present invention. FIG. 1B is a cross-sectional view of the liquid crystal display of FIG. 1A taken along line Ib-Ib ′, and FIG. 1D is a liquid crystal of FIG. 1A. 1D is a cross-sectional view of the liquid crystal display of FIG. 1A taken along line Id-Id ', and FIG. 1E is a layout view of the color filter of the liquid crystal display of FIG. 1A.

The liquid crystal display according to the present exemplary embodiment includes the lower panel 100 having the pixel electrode 82, the upper panel 200 facing the common electrode 90, and the liquid crystal layer 300 interposed therebetween. Include.

First, the lower panel 100 of the liquid crystal display of the present embodiment will be described in detail with reference to FIGS. 1A and 1B.

The gate line 22 is formed in the substantially horizontal direction on the insulating substrate 10, and the gate electrode 26 formed in the form of a protrusion is formed on the gate line 22. A gate line end 24 is formed at the end of the gate line 22 to receive a gate signal from another layer or the outside and transmit the gate signal to the gate line 22. The gate line end 24 is connected to an external circuit. The width is extended. The gate line 22, the gate electrode 26, and the gate line end 24 are referred to as gate wirings.

In addition, on the insulating substrate 10, a storage electrode line 28 extending in the horizontal direction substantially in parallel with the gate line 22 is formed. A sustain electrode 29 having a relatively large area branched from the sustain electrode line 28 is formed. The storage electrode 29 overlaps the drain electrode extension 67, which will be described later, and the storage electrode 29, the drain electrode extension 67, and the gate insulating layer 30 interposed therebetween may include the storage capacitor ( capacitor). Such sustain electrode lines 28 and sustain electrodes 29 are referred to as sustain electrode wirings.

The present invention is not limited to the shape of the sustain electrode wirings 28 and 29 as described above, and the shape of the sustain electrode wirings 28 and 29 in a range that satisfies the conditions for forming a constant storage capacitor with the pixel electrode 82. And the arrangement can be modified in many forms.

The gate wirings 22, 24 and 26 and the sustain electrode wirings 28 and 29 are made of aluminum-based metals such as aluminum (Al) and aluminum alloys, silver (Ag) and silver alloys such as silver-based metals, copper (Cu) and Copper-based metals such as copper alloys, molybdenum (Mo) and molybdenum-based metals such as molybdenum alloys, it may be made of chromium (Cr), titanium (Ti), tantalum (Ta). In addition, the gate lines 22, 24, and 26 and the storage electrode lines 28 and 29 may have a multilayer structure including two conductive layers (not shown) having different physical properties. One of the conductive films is a low resistivity metal such as an aluminum-based metal or a silver-based metal so as to reduce the signal delay or voltage drop of the gate wirings 22, 24, and 26 and the sustain electrode wirings 28 and 29. It consists of a metal, a copper type metal, etc. In contrast, the other conductive layer is made of a material having excellent contact properties with other materials, particularly indium tin oxide (ITO) and indium zinc oxide (IZO), such as molybdenum-based metals, chromium, titanium, tantalum and the like. A good example of such a combination is a chromium bottom film and an aluminum top film and an aluminum bottom film and a molybdenum top film. However, the present invention is not limited thereto, and the gate wirings 22, 24, and 26 and the sustain electrode wirings 28 and 29 may be made of various metals and conductors.

The gate insulating film 30 is formed on the gate wirings 22, 24, 26 and the sustain electrode wirings 28, 29.

On the gate insulating film 30, a semiconductor layer 40 made of hydrogenated amorphous silicon, polycrystalline silicon, or the like is formed. The semiconductor layer 40 may have various shapes such as an island shape and a linear shape. For example, the semiconductor layer 40 may be formed in an island shape on the gate electrode 26 as in the present embodiment. In addition, when the semiconductor layer 40 is formed in a linear shape, the semiconductor layer 40 may be positioned below the data line 62 and may extend to the upper portion of the gate electrode 26.

Resistive contact layers 55 and 56 made of a material such as n + hydrogenated amorphous silicon doped with silicide or n-type impurities at a high concentration are formed on the semiconductor layer 40. The ohmic contacts 55 and 56 may have various shapes such as islands and linear shapes. For example, in the case of the islands of ohmic contact layers 55 and 56, the drain electrode 66 and the source electrode may have different shapes. Located below 65, the linear ohmic contact layer may extend below the data line 62.

The data line 62 and the drain electrode 66 are formed on the ohmic contacts 55 and 56 and the gate insulating layer 30. The data line 62 extends long and crosses the gate line 22 to define a pixel. The source electrode 65 extending from the data line 62 to the top of the semiconductor layer 40 in the form of a branch is formed. At the end of the data line 62, a data line end 68 is formed which receives a data signal from another layer or the outside and transmits the data signal to the data line 62. The data line end 68 is connected to an external circuit. The width is extended. The drain electrode 66 is separated from the source electrode 65 and positioned above the semiconductor layer 40 so as to face the source electrode 65 with respect to the gate electrode 26. The drain electrode 66 includes a rod pattern on the semiconductor layer 40 and a drain electrode extension 67 extending from the rod pattern and having a large area and in which the contact hole 76 is located. The data line 62, the source electrode 65, the drain electrode 66, the drain electrode extension 67, and the data line end 68 are referred to as data wirings.

The data wires 62, 65, 66, 67, and 68 are preferably made of refractory metals such as chromium, molybdenum-based metals, tantalum, and titanium, and a lower resistive material such as a refractory metal and a low resistance material disposed thereon. It may have a multi-layered film structure consisting of an upper film (not shown). Examples of the multilayer film structure include a triple film of molybdenum film, aluminum film, and molybdenum film in addition to the above-described double film of chromium lower film and aluminum upper film or aluminum lower film and molybdenum upper film.

The source electrode 65 overlaps at least a portion of the semiconductor layer 40, and the drain electrode 66 faces the source electrode 65 around the gate electrode 26 and at least partially overlaps the semiconductor layer 40. do. The ohmic contacts 55 and 56 are interposed between the semiconductor layer 40 and the source electrode 65, and the semiconductor layer 40 and the drain electrode 66 to lower the contact resistance therebetween.

A passivation layer 70 made of an insulating layer is formed on the data line 62, the drain electrode 66, and the exposed semiconductor layer 40. The protective film 70 may be formed of a low dielectric constant such as a-Si: C: O, a-Si: O: F, or the like formed of an inorganic material made of silicon nitride or silicon oxide, or plasma enhanced chemical vapor deposition (PECVD). It is made of an insulating material.

In the passivation layer 70, contact holes 76 and 78 exposing the drain electrode 66 and the data line end 68 are formed, respectively, and the passivation layer 70 and the gate insulating layer 30 are formed at the gate line end. The contact hole 74 which exposes the 24 is formed.

On the passivation layer 70, red, green, and blue color filters 72 sequentially arranged for each pixel are formed, and the color filter 72 overlaps the contact hole 76 to expose the drain electrode 66. The opening 73 is formed in the part to be made. As shown in FIG. 1E, the color filter 72 is separated for each pixel using a printing method and formed in an island type. The manufacturing method of the color filter 72 is demonstrated in detail later.

The pixel electrode 82 is formed on the color filter 72 along the shape of the pixel. The pixel electrode 82 is electrically connected to the drain electrode 66 through the contact hole 76. As mentioned above, the color filter 72 is formed in an island shape for each pixel, and the pixel electrode 82 surrounds the color filter 72 so that the color filter 72 is not exposed to the liquid crystal layer 300. This is to prevent the out-gas generated from the color filter 72 from affecting the movement of the liquid crystal molecules constituting the liquid crystal layer 300.

In addition, an auxiliary gate line end 86 and an auxiliary data line end 88 which are connected to the gate line end 24 and the data line end 68, respectively, are formed on the passivation layer 70 through the contact holes 74 and 78. It is. The pixel electrode 82, the auxiliary gate line end 86, and the auxiliary data line end 88 may be formed of a transparent conductor such as ITO or IZO, or a reflective conductor such as aluminum. The auxiliary gate line and data line ends 86 and 88 serve to bond the gate line end 24 and the data line end 68 to an external device.

The pixel electrode 82 is physically and electrically connected to the drain electrode 66 through the contact hole 76 to receive a data voltage from the drain electrode 66.

An alignment layer (not shown) may be coated on the pixel electrode 82, the auxiliary gate line end 86, the auxiliary data line end 88, and the passivation layer 70.

Hereinafter, the relationship between the color filter and the pixel electrode in the liquid crystal display of the present invention will be described with reference to FIGS. 1A, 1C, and 1D.

First, as mentioned above, the color filter 72 is formed in an island shape to be separated for each pixel. The color filter 72 may be formed using a printing method. When the color filter 72 is formed by photolithography, the color filter 72 may be formed by separating the pixels, but the color filter 72 may not be adhered to the lower display panel 100. May cause problems. When the color filter 72 is formed using the printing method, the color filter 72 may be formed by separating the pixels for each pixel, and the adhesion between the color filter 72 and the lower panel 100 may be increased.

As shown in FIGS. 1A and 1C, the color filters 72 of two neighboring pixels are formed to be separated from each other based on the gate line 22. The pixel electrode 82 surrounds the color filter 72 so that each color filter 72 is not exposed to the liquid crystal layer 300.

1A and 1D, the color filters 72 of two neighboring pixels are separated from each other based on the data line 62. The pixel electrode 82 surrounds the color filter 72 so that each color filter 72 is not exposed to the liquid crystal layer 300.

Referring to FIGS. 1A and 1B, the upper panel 200 of the liquid crystal display of the present exemplary embodiment will be described.

The black matrix 94 for preventing light leakage on the insulating substrate 96 made of a transparent insulating material such as glass, and the indium tin oxide (ITO) or indium zinc oxide (IZO) on the insulating substrate 96 and the black matrix 94 The common electrode 90 made of a transparent conductive material such as) is formed. The black matrix 94 is positioned on the gate line 22 and the data line 62 to cover the gate line 22 and the data line 62 on the lower panel 100.

An anti-corrosion film (not shown) may be coated on the common electrode 90 to align the liquid crystal molecules.

When the lower panel 100 and the upper panel 200 having such a structure are aligned and combined, and the liquid crystal layer 200 is formed therebetween, the basic structure of the liquid crystal display device of the present invention is achieved.

The liquid crystal display device is formed by disposing elements such as a polarizing plate and a backlight on the basic structure.

At this time, the polarizing plate (not shown) is disposed one each on both sides of the basic structure and the transmission axis is arranged to be perpendicular to each other.

Hereinafter, a method of manufacturing a liquid crystal display according to an exemplary embodiment of the present invention will be described with reference to FIGS. 1B and 2A to 2E. 2A through 2E are cross-sectional views sequentially illustrating a method of manufacturing a color filter of a liquid crystal display according to an exemplary embodiment of the present invention. A method of manufacturing a liquid crystal display according to an exemplary embodiment of the present invention includes providing a lower panel and an upper panel, and forming a liquid crystal layer.

First, the steps of providing the lower panel will be described. Referring to FIG. 1B, gate wirings 22, 24, and 26 and sustain electrode wirings 28 and 29 are formed on an insulating substrate 10, and a gate insulating film 30 is formed thereon. Subsequently, the semiconductor layer 40, the ohmic contact layers 55 and 56, and the data lines 62, 65, 66, 67, and 68 are formed on the gate insulating layer 30. A protective film 70 made of an insulating film is formed on the data line 62, the drain electrode 66, and the exposed semiconductor layer 40.

Subsequently, an island color filter 72 separated for each pixel is formed on the passivation layer 70 by a printing method. Hereinafter, a method of manufacturing the color filter 72 will be described in detail with reference to FIGS. 2A to 2E.

Specifically, referring to FIG. 2A, a printing plate 410 having at least one printing groove 412 is prepared. The printing groove 412 pattern may be formed in various shapes according to the printing object. However, in the present embodiment, the color filter 72 shown in FIG. 1E is used as the printing object. Therefore, the printing groove 412 is designed in the same pattern as the color filter 72. Subsequently, the resin for color filter 430, which is a material to be printed, is provided on one side of the printing plate 410 from the resin supply unit 420. In this case, the color filter resin 430 may be a liquid to fill a specific space, but may have an viscosity that may maintain a shape when no external force is present, and may be an organic material that may be UV cured or heat cured.

Subsequently, referring to FIG. 2B, the blade 440 is moved to the other side of the printing plate 410 to fill the printing groove 412 with the resin 430 for the color filter provided on the printing plate 410. That is, when the blade 440 is moved while contacting the upper surface of the printing plate 410, the color filter resin 430 is pushed in the moving direction of the blade 440 to be filled in the printing groove 412 existing on the moving path. do. Here, the color filter resin 430 located on the printing plate 410 other than the printing groove 412 is removed by the blade 440, and the resin for color filter 430 remains only in the printing groove 412. . In this embodiment, one blade 440 is shown to perform the filling and removal of the color filter resin 430 at the same time, in contrast, two or more blades are provided with one is used as the filling blade and the other is Can also be used as a removal blade.

Subsequently, referring to FIG. 2C, the transfer roller 450 is rolled on the upper surface of the printing plate 410 filled with the color filter resin 430. The outer periphery of the transfer roller 450 is provided with a transfer sheet 451, so that the color filter resin 430 filled in the printing groove 412 while the transfer roller 450 rolls the printing plate 410 is a transfer sheet ( 451). The outer circumferential length of the transfer roller 450 may be equal to or larger than the width of the printing plate 410 with respect to the rolling direction of the transfer roller 450. In addition, the transfer sheet 451 may be one that is excellent in adhesion with the color filter resin 430 to facilitate the transfer of the color filter resin 430.

Next, referring to FIG. 2D, the transfer roller 450 to which the color filter resin 430 is transferred is rolled on the insulating substrate 10 on which the protective film 70 is formed. At this time, the resin for color filters 430 attached to the transfer sheet 451 is transferred onto the protective film 70. The color filter resin 430 is formed in a separate island shape for each pixel. That is, the color filter resin 430 is preferably formed so as not to overlap the gate line 22 and the data line 62. Since the position and spacing of the color filter resin 430 to be transferred onto the protective film 70 are determined by the printing groove 412 of the printing plate 410, printing is performed according to the shape of the color filter resin 430. The pattern of the groove 412 is adjusted.

Subsequently, referring to FIG. 2E, the color filter resin 430 may be hardened by applying ultraviolet rays or heat to the color filter resin 430 transferred onto the protective film 70 to complete the color filter 72. The opening 73 may be simultaneously formed to expose the drain electrode 66 of FIG. 1B by changing the pattern of the printing groove 412 while forming the color filter 72. In addition, even if the opening 73 is not formed by the printing method, it may be formed by an etching process of forming the contact hole 76 in the protective film 70 later.

Since the color filter 72 includes three colors of red, green, and blue, the color filter 72 may be repeated three times by repeating the steps of FIGS. 2A through 2E corresponding to each color.

After the color filter 72 is completed, referring to FIG. 1B, the pixel electrode 82 is electrically connected to the drain electrode 66 on the color filter 72 and the passivation layer 70 and surrounds the color filter 72. To form. Subsequently, an alignment layer (not shown) is formed thereon to complete the lower panel 100.

Next, referring to FIG. 1B, an upper panel 200 having a black matrix 94, a common electrode 90, and an alignment layer (not shown) is prepared on an insulating substrate 96.

Subsequently, the lower panel 100 and the upper panel 200 are aligned and coupled to each other, and the liquid crystal display device is completed through the liquid crystal layer 300 therebetween.

In the above embodiment, the example using a flat plate type printing plate as a method for forming a color filter, but the present invention is not limited thereto, and the same applies to the case of using a cylindrical plate. 3 is a cross-sectional view illustrating a manufacturing process of a liquid crystal display according to another exemplary embodiment of the present invention. In FIG. 3, an example of using a cylindrical printing plate 510 instead of a flat printing plate is illustrated.

The printing groove 512 is formed on the outer circumference of the cylindrical printing plate 510. When the color filter resin 430 is provided to the cylindrical printing plate 510 from the resin supply unit 420, the color printing resin 430 is moved to the printing groove 512 by the blade 440 while the cylindrical printing plate 510 is rotated. Is filled in. Furthermore, the resin 430 for color filters is transferred to the transfer roller 450 in contact with the cylindrical printing plate 510. The color filter resin 430 transferred to the transfer roller 450 is transferred onto the insulating substrate 10 moving in the rolling direction of the transfer roller 450.

In the above embodiments, the steps of manufacturing the lower panel and the upper panel as a method of manufacturing the liquid crystal display and forming the liquid crystal layer therebetween are described in order, but the present invention is not limited to this order, and the upper panel is manufactured first, The upper panel and the lower panel may be manufactured at the same time.

Although embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

As described above, according to the manufacturing method of the liquid crystal display device according to the present invention, the color filter is formed by separating the color filter for each pixel, and the pixel electrode surrounds the color filter to prevent the color filter from being exposed to the liquid crystal layer. The outgas emitted from can be prevented. Therefore, the afterimage problem can be solved. In addition, although a conventional photolithography process has to be performed three times to form a color filter, the process can be simplified by using the printing method according to the manufacturing method of the present invention.

Claims (11)

Transferring the resin for color filter filled in the printing groove of the printing plate onto the insulating substrate; And Comprising the step of curing the resin for the color filter on the insulating substrate to complete the color filter. According to claim 1, And the color filter is an island type separated for each pixel constituting the liquid crystal display. The method of claim 1, wherein before the transferring step, Forming a gate line and a data line orthogonal to each other on the insulating substrate. The method of claim 3, wherein And the color filter does not overlap the gate line. The method of claim 3, wherein And the color filter does not overlap the data line. The method of claim 3, wherein And forming a protective film made of an inorganic material on the data line. According to claim 1, A method of manufacturing a liquid crystal display device comprising repeating the transferring step and the curing step three times using the red, green, and blue resins for color filters, respectively. The method of claim 1, wherein after the color filter is completed, And forming a pixel electrode surrounding the color filter so that the color filter is not exposed to the outside on the color filter. The method of claim 1, wherein the transferring step, Filling the resin for the color filter into the printing groove; Transferring the resin for color filter in the printing groove to a transfer roller; And And transferring the resin for color filter transferred to the transfer roller onto the insulating substrate. According to claim 1, The printing plate is a flat panel or cylindrical liquid crystal display device manufacturing method. The method of claim 1, wherein after the color filter is completed, Forming a pixel electrode on the color filter; Bonding the color filter, the lower substrate on which the pixel electrode is formed, and the upper substrate on which the common electrode is formed; And And interposing a liquid crystal layer between the lower substrate and the upper substrate.

Images