KR100921898B1 - Fabrication method for LCD device - Google Patents

Abstract

In the method of manufacturing a liquid crystal display device according to the present invention, in the process of manufacturing a liquid crystal display device, the first substrate and the second substrate constituting the liquid crystal display device, the array of the first substrate and the second substrate (TFT array or color filter array) The transparent protective film is formed in the bonding key / process key forming area in order to protect the bonding key / process key provided in the outer portion of the region.

According to the present invention, the transparent protective film is formed of an organic film, the organic film may be formed at the same time using the same material as the overcoat layer in the process of applying the overcoat layer, the organic film is formed of a photoreactive organic insulating film May be

In addition, another example of the manufacturing method of the liquid crystal display device according to the present invention forms a black matrix having a predetermined distance on the substrate, and adheres to the substrate outer portion of the region where the black matrix is formed by using the same material as the black matrix. Forming a key and / or a process key; Forming a color filter layer on the black matrix; And forming an overcoat layer on the color filter layer, and forming a transparent protective film on an area where the bonding key and / or the process key are formed using the same material as the overcoat layer. It is characterized in that it forms an upper substrate constituting the liquid crystal display device, including.

Description

Liquid crystal display device manufacturing method {Fabrication method for LCD device}

1 is a view showing an example of a shape of a bonding key provided on each substrate for bonding of an upper plate and a lower plate in a general liquid crystal display manufacturing process.

2 conceptually illustrates a shape in which an overcoat layer is formed on a substrate by a method of manufacturing a liquid crystal display according to the present invention.

3 is a schematic plan view of a transverse electric field type liquid crystal display device manufactured by a liquid crystal display device manufacturing method according to the present invention.

4 is a cross-sectional view taken along line AA ′ of FIG. 3.

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

11, 16 ... bonding key 20 ... board

21 ... TFT array / color filter array formation area

22, 24 ... Overcoat layer 23 ... Bonding / process key forming area

301 ... gate wiring 302 ... data wiring

303 ... common wiring 304 ... gate electrode

305 semiconductor layer 306 source electrode

307 ... drain electrode 308 ... common electrode

309 ... data electrode 310 ... black matrix                 

311 ... ohmic contact layer 312 ... gate insulating film

313 ... Protective film 314 ... First alignment film

317 ... color filter 318 ... overcoat layer

319 .. second alignment layer 320 .. first substrate

330 ... Second substrate 340 ... Liquid crystal layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device. In particular, a bonding key formed on each substrate for alignment of a lower plate and a top plate constituting the liquid crystal display device and a process key formed on each substrate due to a process progress need to be made in the manufacturing process. The present invention relates to a method for manufacturing a liquid crystal display device that can prevent damage.

In general, CRT (or CRT: Cathode Ray Tube) has been the most used screen display device for displaying image information on the screen, which is inconvenient to use because it is bulky and heavy compared to the display area. Followed.

Accordingly, a thin film type flat panel display device having a small display area that can be easily used in any place even though the display area is large has been developed, and is gradually replacing the CRT display device. In particular, liquid crystal displays (LCDs) exhibit superior display resolution than other flat panel displays, and exhibit high response speed as compared to CRTs when a moving image is realized.

As is known, the driving principle of the liquid crystal display device utilizes the optical anisotropy and polarization properties of the liquid crystal. Since the liquid crystal is thin and long in structure, the direction of the molecular arrangement can be controlled by artificially applying an electromagnetic field to the liquid crystal molecules having directionality and polarization in the molecular arrangement. Therefore, if the alignment direction is arbitrarily adjusted, light may be transmitted or blocked according to the alignment direction of the liquid crystal molecules by optical anisotropy of the liquid crystal, thereby displaying colors and images.

The active matrix liquid crystal display device adds an active element having a nonlinear characteristic to each pixel arranged in a matrix form, and controls the operation of each pixel by using the switching characteristics of the element. The memory function is implemented through.

In general, a manufacturing process of a liquid crystal display device includes a process of preparing a lower plate, which is a thin film transistor array substrate, a process of preparing an upper plate, which is a color filter array substrate, a process of bonding an upper plate and a lower plate, and injecting liquid crystal between two bonded substrates. The process proceeds in the order of attaching the polarizing plate to the outer surfaces of the two bonded substrates, the module process and the like.

In such a series of steps, in the step of joining the upper plate and the lower plate, the alignment position of the upper plate and the lower plate is adjusted by using the bonding key provided on each substrate. The bonding key formed on the lower plate is formed in a predetermined shape on the outer periphery of the array of the lower plate using a gate forming material or a source / drain forming material during a manufacturing process of forming a pixel array including a thin film transistor and a pixel electrode on the lower plate. In addition, the bonding key formed on the upper plate is provided in a predetermined shape on the outer periphery of the array of the upper plate with a black matrix forming material during the manufacturing process of forming the color filter array on the upper plate.

1 is a view showing an example of a shape of a bonding key provided on each substrate for bonding of an upper plate and a lower plate in a general liquid crystal display manufacturing process.

The bonding key of the liquid crystal display device is formed on the outer periphery of the array of each substrate, and FIG. 1 illustrates a case where the upper plate and the lower plate are bonded together, and the bonding key 11 formed on the lower plate has a cross shape having a predetermined width. In this case, the splicing key 16 formed on the top plate shows a case in which a sickle shape is formed so as to correspond to the four borders of the cross shape at predetermined intervals with the cross shape boundary.

As described above, in the case where the upper plate and the lower plate are bonded together, the fitting key 16 of the upper plate and the fitting key 11 of the lower plate correspond to the cross shape and sickle shape at predetermined intervals as shown in FIG. If the alignment of the two substrates is exactly matched, the bonding key 16 of the upper plate and the bonding key 11 of the lower plate are positioned at regular intervals. Through this method it is possible to accurately align the upper plate and the lower plate when bonding.

In addition, in addition to the bonding key, process keys for processing a process, such as a PI printing key used in a PI printing process and a scribe key used in a scribe process, are formed on the outer portion of the upper and lower plates of the liquid crystal display. Is formed.

However, the process keys for the process proceeding provided in the upper plate and the lower plate may be damaged in the process of the cell process, such as cleaning, alignment film printing, rubbing, and sometimes completely lost. Accordingly, when the bonding key is lost, a problem arises in that the top and bottom plates are not properly aligned, and when other process keys are lost, the corresponding process cannot be smoothly performed. Is generated.

According to the present invention, the bonding key formed on each substrate for alignment of the lower plate and the upper plate constituting the liquid crystal display device and the process key formed on each substrate due to the necessity of process progress can be prevented from being damaged in the manufacturing process. It is an object of the present invention to provide a method for manufacturing a liquid crystal display device.

In order to achieve the above object, a method of manufacturing a liquid crystal display device according to the present invention, in manufacturing a liquid crystal display device, in the process of the first substrate and the second substrate constituting the liquid crystal display device, the first In order to protect the bonding key / process key provided at the outer periphery of the array of the substrate and the second substrate (TFT array or color filter array), the transparent protective film is formed on the bonding key / process key forming region. have.

According to the present invention, the transparent protective film is formed of an organic film, the organic film may be formed at the same time using the same material as the overcoat layer in the process of applying the overcoat layer, the organic film is formed of a photoreactive organic insulating film May be

In addition, another example of the manufacturing method of the liquid crystal display device according to the present invention in order to achieve the above object,

Forming a black matrix having a predetermined distance on the substrate, and forming a bonding key and / or a process key on the outer periphery of the substrate where the black matrix is formed using the same material as the black matrix;

Forming a color filter layer on the black matrix; And

Forming an overcoat layer on the color filter layer and forming a transparent protective film on an area where the bonding key and / or the process key are formed using the same material as the overcoat layer; It is characterized in that it forms an upper substrate constituting the liquid crystal display device, including.

According to the present invention, the black matrix may be formed of a resin-based material, or may be formed of a chromium-based material.

In addition, another example of the manufacturing method of the liquid crystal display device according to the present invention in order to achieve the above object,

Forming a TFT array on the substrate, and forming a bonding key and / or a process key at the outer periphery of the substrate where the TFT array is formed; And

Forming a protective film and an overcoat layer on the TFT array, and forming a transparent protective film on a region where the bonding key and / or the process key are formed using the same material as the overcoat layer; It is characterized in that the lower substrate to form a liquid crystal display device including.

According to the present invention, the bonding key and / or the process key may be formed using the same material as the gate electrode when forming the gate electrode forming the TFT array.

Further, according to the present invention, the bonding key and / or the process key may be formed using the same material as the source / drain electrodes when forming the source / drain electrodes forming the TFT array.

According to the present invention, the bonding key formed on each substrate for the alignment of the lower plate and the upper plate constituting the liquid crystal display and the process key formed on each substrate due to the necessity of process progress are prevented from being damaged in the manufacturing process. There is an advantage to this.

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

According to the liquid crystal display device manufacturing method according to the present invention, in the process of the first substrate and the second substrate constituting the liquid crystal display device, the array of the first substrate and the second substrate (TFT array or color filter array) In order to protect the bonding key / process key provided at the outer portion of the region, a transparent protective film is formed on the bonding key / process key forming region.

FIG. 2 is a diagram illustrating an example, and conceptually illustrates a shape in which an overcoat layer is formed on a substrate by a method of manufacturing a liquid crystal display device according to the present invention.

Referring to FIG. 2, a TFT array / color filter array forming region 21 on which a TFT array or a color filter array is formed is formed on the substrate 20, and is formed outside the TFT array / color filter array region 21. A bonding key / process key forming area 23 is formed in which a bonding key or a process key is formed. 2 illustrates a case where a plurality of TFT arrays / color filter arrays are formed on one substrate 20.

Here, the bonding key refers to a reference key formed on each substrate for bonding alignment of the upper plate and the lower plate in the manufacturing process of the liquid crystal display device, and the process key refers to the reference key formed on each substrate as necessary for the progress of the process.

Such a bonding key and a process key are directly exposed to the outside in a cell manufacturing process such as alignment film printing and rubbing, thereby causing a problem that may be damaged or lost during the cell manufacturing process. Accordingly, in the present invention, as shown in FIG. 2, the overcoat layers 22 and 24 are formed not only in the TFT array / color filter array formation region 21 but also in the bonding key / process key formation region 23, respectively. In this way, the bonding key / process key can be prevented from being damaged in the cell manufacturing process.

In FIG. 2, the case in which the overcoat layer 24 is formed in the bonding key / process key forming region 23 to protect the bonding key / process key is described as an example. However, in the manufacturing process of the liquid crystal display device, only the overcoat layer is used. Alternatively, a photoreactive organic insulating film or the like may be formed as a transparent protective film for protecting the bonding key / process key according to the manufacturing process.

In this case, when the overcoat layer is formed of the transparent protective film, it may be simultaneously formed using the same material for forming the overcoat layer in the process of applying the overcoat layer on the TFT array or the color filter array.

The manufacturing process in which the protective film for the bonding key / process key is formed on the TFT substrate will be described in more detail. A TFT array is formed on the substrate, and the bonding key and / or process is formed on the outer periphery of the substrate in the region where the TFT array is formed. Forming a key; And forming a protective film and an overcoat layer on the TFT array, and forming an overcoat layer on a region where the bonding key and / or the process key are formed using the same material as the overcoat layer. It can be represented as.

Here, the bonding key and / or the process key formed on the TFT substrate may be formed using the same material as the gate electrode when forming the gate electrode of the TFT array, and source / drain electrodes of the TFT array. In forming, it may be formed using the same material as the source / drain electrodes.

Further, when a photoreactive organic insulating film is formed with the transparent protective film for protecting the bonding key / process key, the photoreactive organic insulating film is formed in the step of forming a photoresist organic insulating film as a photoresist film on a TFT array. Using the same material as and can be formed at the same time. A manufacturing method of a liquid crystal display device using a photoreactive organic insulating film as a photoresist film on a TFT array is a known process, and a detailed description thereof will be omitted here.

Meanwhile, when the manufacturing process of forming a protective film for the bonding key / process key on the color filter substrate is further explained, a black matrix having a predetermined interval is formed on the substrate, and the black material is formed using the same material as the black matrix. Forming a joining key and / or a process key at the outer periphery of the substrate where the matrix is formed; Forming a color filter layer on the black matrix; And forming an overcoat layer on the color filter layer and forming a transparent protective film on an area where the bonding key and / or the process key are formed using the same material as the overcoat layer.

Here, the Cr-based material may be used as the black matrix forming material, or the resin-based material may be used.

Next, a brief description will be made of a transverse electric field type liquid crystal display device manufactured by applying the method for manufacturing a liquid crystal display device according to the present invention.

3 is a schematic plan view of a transverse electric field type liquid crystal display device manufactured by a method of manufacturing a liquid crystal display device according to the present invention, and FIG. 4 is a cross-sectional view taken along line AA ′ of FIG. 3.

3 and 4, the transverse electric field type liquid crystal display device manufactured by the liquid crystal display device manufacturing method according to the present invention includes a gate wiring 301 and a data wiring (vertically and vertically) formed on the first substrate 320. 302 is arranged. The pixel area is defined by the gate line 301 and the data line 302. Although the actual liquid crystal panel is composed of many pixel areas, only one pixel is shown in the drawing for convenience of description.

A common wiring 303 parallel to the gate wiring 301 is arranged in the pixel area, and a thin film transistor (TFT) is formed at the intersection of the gate wiring 301 and the data wiring 302. Formed. The TFT includes a gate electrode 304, a gate insulating film 312, a source / drain electrode 306 and 307, a semiconductor layer 305, and an ohmic contact layer 311, and the gate electrode 304 and the source. The / drain electrodes 306 and 307 are connected to the gate wiring 301 and the data wiring 302, respectively. The gate insulating film 312 is laminated over the entire substrate.

Meanwhile, the common electrode 308 and the data electrode 309 are formed in parallel to each other in the pixel region to apply a transverse electric field together. The common electrode 308 is formed on the first substrate 320 at the same time as the gate electrode 304 and connected to the common wiring 303, and the data electrode 309 is formed on the gate insulating layer 312 by the source / drain electrode 306. 307 is formed at the same time as the source / drain electrodes 306 and 307 of the TFT. A passivation layer 313 and a first alignment layer 314 for alignment of liquid crystal are formed on the common electrode 308 and the data electrode 309 over the entire first substrate 320.

Meanwhile, a black matrix 316 and a color filter layer 317 are formed on the second substrate 330 to prevent light from leaking into the TFT, gate wiring 301, and data wiring 301 regions. An overcoat layer 318 is formed on the black matrix 316 and the color filter layer 317 to remove the step difference, and a second alignment layer 319 is formed thereon for alignment of the liquid crystal. In addition, when the overcoat layer 318 is formed on the black matrix 316 and the color filter layer 317, the overcoat layer is simultaneously formed on the outer portion where the bonding key / process key is formed, thereby forming It is possible to form a protective film for.

Here, the case where the protective film for the bonding key / process key is formed only on the second substrate, which is the color filter substrate, is described as an example. In the transverse electric field type liquid crystal display device, a resin-based material is often used as a black matrix. In this case, since the bonding key / process key is formed of a resin-based material, the application example will be briefly described in consideration of the increased risk of loss of the bonding key / process key in the cell manufacturing process.

Meanwhile, as shown in FIG. 2, the overcoat is applied not only to the TFT array / color filter array forming region 21 provided in the center of the substrate 20 but also to the bonding key / process key forming region 23 provided at the outer portion of the substrate 20. By forming the layers 22 and 24, respectively, the step difference in each area can be reduced. Accordingly, damage to the bonding key / process key can be prevented in the cell manufacturing process, and horizontal lines can be prevented from occurring during the alignment film printing and rubbing.

As described above, according to the method of manufacturing the liquid crystal display device according to the present invention, a bonding key formed on each substrate for alignment of the lower plate and the upper plate of the liquid crystal display device is formed on each substrate by the necessity of process progress. There is an advantage that can prevent the process key from being damaged in the manufacturing process. Accordingly, damage to the bonding key / process key can be prevented in the cell manufacturing process, thereby improving the overall manufacturing yield of the liquid crystal display device.

In addition, according to the manufacturing method of the liquid crystal display device according to the present invention, by reducing the step between the center portion and the outer portion of the substrate, it is possible to prevent the generation of horizontal lines in advance during the alignment film printing and rubbing process in the cell manufacturing process There is this.

Claims (10)

In manufacturing a liquid crystal display device, In the process of processing the first substrate and the second substrate constituting the liquid crystal display device, a bonding key / process key provided at an outer portion of an array (TFT array or color filter array) region of the first substrate and the second substrate. A photoreactive organic insulating film is formed in the bonding key / process key formation region for protection of the liquid crystal display device. delete delete delete Forming a black matrix having a predetermined distance on the substrate, and forming a bonding key and / or a process key on the outer periphery of the substrate where the black matrix is formed using the same material as the black matrix; Forming a color filter layer on the black matrix; And Forming an overcoat layer on the color filter layer and forming a transparent protective film on an area where the bonding key and / or the process key are formed using the same material as the overcoat layer; Forming an upper substrate constituting the liquid crystal display device including a liquid crystal display device. The method of claim 5, And the black matrix is formed of a resin-based material. The method of claim 5, And the black matrix is formed of a chromium-based material. delete delete delete

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