KR20070074986A - Display device and method for fabricating the display device - Google Patents

Abstract

A display device and a method for manufacturing the same are provided to improve the reliability of the display device, by using an inorganic alignment layer instead of an organic alignment layer and forming ion collectors for absorbing ions from a liquid crystal layer in the inorganic alignment layer. A first substrate(110) and a second substrate(210) has a block area(BA) and a transmission area(TA). A light shielding pattern(120) is formed on the first substrate. A first inorganic alignment layer(160) is formed above the light shielding pattern. A signal line(220) is formed on the second substrate. A second inorganic alignment layer(260) is formed above the signal line. Ion collectors are formed in at least one of the first inorganic alignment layer and the second inorganic alignment layer correspondingly to the block area.

Description

DISPLAY DEVICE AND METHOD FOR FABRICATING THE DISPLAY DEVICE}

1 is a cross-sectional view schematically illustrating a display device according to an exemplary embodiment of the present invention.

2A and 2B are cross-sectional views illustrating a method of manufacturing a first display substrate constituting a display device according to an exemplary embodiment of the present invention.

3A and 3B are cross-sectional views illustrating a method of manufacturing a second display substrate constituting a display device according to an exemplary embodiment of the present invention.

♧ explanation of the reference numerals for the main parts of the drawing.

100: first display substrate 110: first substrate

120 shading film pattern 160 first alignment film

200: second display substrate 210: second substrate

260: second alignment layer

The present invention relates to a display device and a manufacturing method thereof.

In general, a flat panel display (FPD) is a display device that provides a thin and flat screen, and is typically used as a liquid crystal display device (LCD), a large digital television, which is widely used as a notebook computer monitor. Plasma displays (PDPs), or organic electroluminescent displays (OELDs) used in mobile phones.

The liquid crystal display displays an image by changing an electrical signal into visual information by using a property in which light transmittance of a liquid crystal, which is an intermediate state material between a liquid and a crystal, is changed according to an applied voltage. A typical liquid crystal display device is composed of two substrates provided with electrodes and a liquid crystal layer interposed between the two substrates. Such a liquid crystal display device is lighter in weight, smaller in volume, and operates with less power than other display devices having the same screen size.

Usually, an alignment film is formed on the electrode of a board | substrate, and a liquid crystal molecule has a pretilt angle in a specific direction by this alignment film. The alignment film is usually formed by printing a polyimide organic film and then rubbing by rotating a roller on the organic film. However, as the substrate is enlarged in recent years, when rubbing the organic alignment film formed on the large substrate, the uniformity of the rubbing direction is inferior. In addition, there is a problem in that the chemical stability is poor due to the nature of the organic polymer is easily degraded by thermal and electrical stress in the manufacturing process. As an alternative to the organic alignment layer having such a problem, research on an inorganic alignment layer is underway.

However, the inorganic alignment layer has a disadvantage in that a voltage holding ratio (VHR) is lower than that of the organic alignment layer. That is, the organic alignment layer is mostly composed of a polymer composed of imide bonds. The polyimide alignment layer absorbs impurities in the liquid crystal to increase the VHR in the cell. However, the inorganic alignment film cannot absorb impurity ions in the liquid crystal, so that the VHR falls. In addition, the reliability of the liquid crystal display may be degraded, such as a decrease in the voltage of the common electrode due to the residual DC voltage generated by the impurity ions.

SUMMARY OF THE INVENTION The present invention has been proposed in consideration of the above-mentioned situation, and a technical object of the present invention is to provide a display device having improved reliability and a method of manufacturing the same.

A display device according to an exemplary embodiment of the present invention may include a first substrate and a second substrate including a light blocking region and a light transmitting region, a light blocking layer pattern formed on the first substrate, a first inorganic alignment layer formed on the light blocking layer pattern, and the second substrate. A signal wire formed on the second substrate, a second inorganic alignment film formed on the signal wire, and an ion collector formed on at least one of the first inorganic alignment film and the second inorganic alignment film in the light blocking region.

In this embodiment, the first and second inorganic alignment layers may be formed of silicon oxide.

In this embodiment, the ion collector may be a dangling bond formed on at least one surface of the first inorganic alignment layer and the second inorganic alignment layer by irradiation of a laser or an ion beam.

In this embodiment, the ion collector may be formed in the central portion of the light blocking region, and the central portion of the light blocking region may be spaced at least 3 μm from a boundary between the light blocking region and the light transmitting region.

A method of manufacturing a display device according to an exemplary embodiment of the present invention includes preparing a first substrate and a second substrate including a light blocking region and a light transmitting region, forming a light blocking layer pattern on the first substrate, and forming a light blocking layer pattern on the light blocking layer pattern. A first inorganic alignment layer is formed, a signal wiring is formed on the second substrate, a second inorganic alignment layer is formed on the signal wiring, and at least one of the first inorganic alignment layer and the second inorganic alignment layer in the light shielding area; Forming an ion collector on either.

In this embodiment, the first and second inorganic alignment layers may be formed of silicon oxide.

In this embodiment, the ion collector may be formed by irradiating at least one of the first inorganic alignment layer and the second inorganic alignment layer with a laser or an ion beam.

In this embodiment, the ion collector may be formed at least 3㎛ spaced apart from the boundary of the light blocking region and the light transmitting region.

In this embodiment, the thickness of the first and second inorganic alignment layer is 100nm, the energy of the irradiated laser or ion beam may be 20 ~ 140mJ.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosure may be made thorough and complete, and to fully convey the spirit of the present invention to those skilled in the art.

Although terms such as first and second are used herein to describe a substrate, an alignment film, an ion collector, and the like, the substrate, the alignment film, the ion collector, and the like should not be limited by these terms. These terms are only used to distinguish one given substrate, alignment layer, and ion collector from another substrate, alignment layer, and ion collector. In addition, where it is mentioned that a film is on another film or substrate, it means that it may be formed directly on another film or substrate, or a third film may be interposed therebetween. In the drawings, the thickness or the like of the film or regions may be exaggerated for clarity.

1 is a cross-sectional view schematically illustrating a display device according to an exemplary embodiment of the present invention. Referring to FIG. 1, the display device 300 includes a first display substrate 100 and a second display substrate 200 including a light blocking area BA and a light transmitting area TA. In addition, the display device 300 may further include a liquid crystal layer (not shown) interposed between the first display substrate 100 and the second display substrate 200.

The first display substrate 100 includes a first substrate 110, a light blocking film pattern 120, a common electrode 150, and a first alignment layer 160.

The first substrate 110 is made of a transparent insulating material such as glass. The light blocking film pattern 120 is positioned on the first insulating substrate 110. The light blocking layer pattern 120 may be formed of a material that blocks light, for example, an organic material such as a photoresist or a metal material such as chromium. An area in which the light shielding film pattern 120 is formed in the first substrate 110 corresponds to a light shielding area BA that blocks light provided from the outside, and a region partitioned in a matrix by the light shielding film pattern 120 transmits light. It corresponds to the light transmission area TA. The color filter 130 is formed between the light blocking film patterns 120. The color filter 130 may be formed by alternately arranging a red filter, a green filter, and a blue filter.

The overcoat layer 140 covers the first substrate 110 on which the light blocking film pattern 120 and the color filter 130 are formed. The overcoating layer 140 removes a step generated between the color filter 130 and the light blocking film pattern 120.

The common electrode 150 and the first alignment layer 160 are sequentially disposed on the overcoat layer 140. The common electrode 150 is made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The alignment layer 160 may be made of an inorganic material, for example, silicon oxide (SiO _X ). The ion collector is positioned in the first alignment layer 160 positioned in the central portion S of the light blocking area BA.

Chemical structure 1 schematically shows the chemical structure of the silicon oxide constituting the alignment layer, and chemical structure 2 schematically shows the chemical structure of the silicon oxide having an ion collector according to an embodiment of the present invention.

[Chemical Structural Formula 1]

[Chemical Structural Formula 2]

That is, the ion collector is not formed separately from the first alignment layer 160, but may be formed by laser or ion beam treatment of the alignment layer 160 in a predetermined region. That is, when a laser or an ion beam is processed on the surface of the first alignment layer 160, dangling bonds are formed on the surface of the silicon oxide constituting the alignment layer 160. Accordingly, the silicon atom and the oxygen atom are ionized, and the ionized silicon atom and the oxygen atom function as collectors of impurity ions. However, since the alignment of the liquid crystal in the transmissive area TA has a great influence on the image realization, it is preferable that the ion collector be formed only in the light shielding area BA that does not affect the image realization. In addition, when the property of the alignment layer 160 is changed at the edge R of the light blocking area BA, the alignment of the liquid crystals in the light transmitting area TA may be adversely affected. It is preferable to form only in S). Therefore, the width of the edge R of the light blocking area BA may be 3 μm or more. That is, the central portion S of the light blocking area BA may be spaced at least 3 μm from a boundary between the light blocking area BA and the light transmitting area TA.

The second display substrate 200 includes a second substrate 210, a thin film transistor (not shown), a pixel electrode 250, and a second alignment layer 260.

The second substrate 210 is made of a transparent insulating material such as glass. A plurality of pixel areas PA is disposed in a matrix form by a plurality of gate lines 220 and a plurality of data lines (not shown) extending in directions perpendicular to each other on the second substrate 210. The plurality of gate lines 220 and the plurality of data lines are provided in the light blocking area BA.

Each pixel area PA includes a pixel including a thin film transistor and a pixel electrode 250. The thin film transistor includes a gate electrode branched from the gate line 220, a source electrode branched from the data line, and a drain electrode spaced apart from the source electrode. The drain electrode is electrically connected to the pixel electrode 250.

The second display substrate 200 may further include a gate insulating layer 230 and an organic layer 240 formed between the gate line 220 and the pixel electrode 250.

In the second alignment layer 260, the ion collector may be positioned at the central portion S of the light blocking area BA. Ion collectors positioned on the second alignment layer 260 may also be formed by laser or ion beam irradiation.

The first display substrate 100 is coupled to face the second display substrate 100 such that the common electrode 150 faces the pixel electrode 250 of the second display substrate 200. In this case, the first display substrate 100 and the second display substrate 200 may be spaced apart from each other by a spacer (not shown) disposed between the two display substrates.

Impurity ions included in the liquid crystal layer (not shown) provided between the first display substrate 100 and the second display substrate 200 may be absorbed by the ion collectors formed on the alignment layers 160 and 260 of the light blocking area BA. Can be. As a result, the voltage holding ratio of the display device 300 may increase. By forming the alignment layers 160 and 260 as inorganic layers, process problems that may occur when forming the organic alignment layer may be solved, thereby increasing the reliability of the display device.

Hereinafter, a method of manufacturing a liquid crystal display device according to an exemplary embodiment of the present invention will be described.

 2A and 2B are cross-sectional views illustrating a method of manufacturing a first display substrate.

First, referring to FIG. 2A, a light blocking film pattern 120 is formed on a first substrate 110 including a light blocking area BA and a light transmitting area TA. The light blocking film pattern 120 corresponds to the light blocking area BA. The first substrate 110 may be formed of a transparent insulating material such as glass, and the light blocking layer pattern 120 may be formed of an organic material such as a photoresist or a metal material such as chromium. The color filter 130 is formed between the light blocking film patterns 120. The color filter 130 may be formed of photoresist dyed red, green, and blue. An overcoating layer 140 may be formed to remove a step between the color filter 130 and the light blocking layer pattern 120.

The common electrode 150 and the first alignment layer 160 are sequentially formed on the overcoat layer 140. The common electrode 150 may be formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The first alignment layer 160 may be formed of an inorganic material such as silicon oxide (SiO _X ) through a deposition method. Since the inorganic alignment layer can be formed by a vapor deposition method as described above, a drying / heating step of the alignment layer that passes through the organic alignment layer is not required. Therefore, the forming process can be very simple and the yield can be increased. In addition, since the liquid crystal display device may not be contaminated by organic materials, the reliability of the device may be improved.

Referring to FIG. 2B, a mask 500 is disposed on the first alignment layer 160. The mask 500 includes a light transmitting part 510 for passing a laser or an ion beam and a light blocking part 520 for blocking the light. The laser or ion beam passes through the light transmitting portion 510 of the mask 500 corresponding to the center portion S of the light blocking area BA to reach the first alignment layer 160. In the first alignment layer 160 irradiated with a laser or an ion beam, a dangling bond is formed on the surface of the silicon oxide, thereby forming ion collectors having ionized silicon atoms and oxygen atoms, that is, the chemical formula (2). That is, the ion collector may be formed at the central portion S of the light blocking area BA, and may not be formed at the edge R. The width of the edge R may be 3 μm or more. The mask 500 may not be used depending on a device for irradiating a laser or ion beam.

3A and 3B are cross-sectional views illustrating a method of manufacturing a second display substrate.

Referring to FIG. 3A, a gate line 220 and a gate insulating layer 230 are formed on the second substrate 210 including the light blocking area BA and the light transmitting area TA. The gate line 220 may be formed by stacking molybdenum (Mo), aluminum (Al), an alloy thereof, or the like in the light blocking region BA, and the gate insulating layer 230 may be formed of silicon nitride. The organic layer 240, the pixel electrode 250, and the second alignment layer 260 are sequentially formed on the gate insulating layer 230. Although not shown, a data line may be formed on the gate insulating layer 230 in a direction crossing the gate line 220. The pixel electrode 250 may be formed of a transparent conductive material such as an indium tin oxide (ITO) or an indium zinc oxide (IZO). The second alignment layer 260 may be formed of an inorganic material such as silicon oxide (SiO _X ) through a deposition method.

Referring to FIG. 3B, a mask 600 is disposed on the second alignment layer 260. The mask 600 includes a light transmitting part 610 for passing a laser or an ion beam and a light blocking part 620 for blocking the light. The laser or ion beam passes through the light transmitting portion 610 of the mask 600 corresponding to the center portion S of the light blocking area BA to reach the second alignment layer 260. In the second alignment layer 260 to which the laser or ion beam is irradiated, dangling bonds are formed on the surface of the silicon oxide, thereby forming ion collectors having ionized silicon atoms and oxygen atoms, that is, the chemical formula (2). That is, the ion collector may be formed at the central portion S of the light blocking area BA, and may not be formed at the edge R. The width of the edge R may be 3 μm or more. The mask 600 may not be used depending on a device for irradiating a laser or ion beam.

In addition, since the ion collector of the second alignment layer 260 is formed at a position corresponding to the ion collector of the first alignment layer 160, the same mask as that used to form the ion collector on the first alignment layer 160 is used. Can be used.

So far, the present invention has been described with reference to the preferred embodiment (s). Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the embodiments disclosed herein should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

According to one embodiment of the present invention, an inorganic alignment layer may be formed instead of an organic alignment layer having various problems in process, thereby increasing reliability of the device.

According to an embodiment of the present invention, an ion collector capable of absorbing impurity ions of the liquid crystal layer may be formed in the inorganic alignment layer, thereby making up for the disadvantages of the inorganic alignment layer.

Claims (10)

A first substrate and a second substrate including a light blocking region and a light transmitting region; A light blocking film pattern formed on the first substrate; A first inorganic alignment layer formed on the light blocking layer pattern; A signal wire formed on the second substrate; A second inorganic alignment layer formed on the signal line; And And an ion collector formed on at least one of the first inorganic alignment layer and the second inorganic alignment layer in the light blocking region. The method of claim 1, The first and second inorganic alignment layers are formed of silicon oxide. The method of claim 1, The ion collector is a dangling bond formed on a surface of at least one of the first inorganic alignment layer and the second inorganic alignment layer by irradiation of a laser or an ion beam. The method of claim 1, The ion collector is formed in the center of the light blocking area. The method of claim 4, wherein And a central portion of the light blocking area spaced at least 3 μm from a boundary between the light blocking area and the light transmitting area. Preparing a first substrate and a second substrate including a light blocking region and a light transmitting region; Forming a light shielding film pattern on the first substrate; Forming a first inorganic alignment layer on the light shielding pattern; Forming signal wiring on the second substrate; Forming a second inorganic alignment film on the signal wiring; And forming an ion collector on at least one of the first inorganic alignment layer and the second inorganic alignment layer in the light blocking region. The method of claim 6, The first and second inorganic alignment layers are formed of silicon oxide. The method of claim 6, Forming the ion collector, A method of manufacturing a display device by irradiating at least one of the first inorganic alignment layer and the second inorganic alignment layer with a laser or an ion beam. The method of claim 6, And the ion collector is formed at least 3 μm apart from a boundary between the light blocking region and the light transmitting region. The method of claim 6, The thickness of the first and second inorganic alignment layers is 100 nm, The energy of the irradiated laser or ion beam is 20 ~ 140mJ manufacturing method of the display device.

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