KR20030095813A - Method for manufacturing liquid crystal display device - Google Patents

Abstract

PURPOSE: A method for manufacturing a liquid crystal display is provided to reduce process hours by measuring an amount of the liquid crystal dropped from each liquid crystal syringe at the same time, and promptly form a liquid crystal layer of a large liquid crystal display. CONSTITUTION: A plurality of liquid crystal syringes(102) are mounted at a head(104) in a liquid crystal dispensing device(100) to drop liquid crystal. A plurality of measuring containers(106) as many as the liquid crystal syringes are supported by a robot arm under the liquid crystal syringes. A plurality of digital scales(110) are arranged under the measuring containers as many as the measuring containers to accurately measure an amount of the liquid crystal dropped from each liquid crystal syringe.

Description

Manufacturing method of liquid crystal display device {METHOD FOR MANUFACTURING LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a method for manufacturing a liquid crystal display device, and more particularly, to a method for manufacturing a liquid crystal display device to which a liquid crystal drop injection method is applied.

As the information society develops, the demand for display devices is increasing in various forms, and in recent years, the LCD (Lipuid Crystal Display Device), PDP (Plasma Display Panel), ELD (Electro Luminescent Display), and VFD (Vacuum Fluorescent) Various flat panel display devices such as displays have been studied, and some of them are already used as display devices in various devices.

Among them, liquid crystal displays are the most widely used, replacing the cathode ray tubes for mobile image display devices because of their excellent image quality, light weight, thinness, and low power consumption. In addition to the same mobile type, various developments have been made for television monitors.

The LCD is composed of two substrates coupled to face each other and a liquid crystal material injected between them to generate a phase transition according to a change in temperature or a change in concentration.

The liquid crystal is a material having an intermediate property between the liquid and the solid having the fluidity of the liquid and the long range order of the solid. That is, it means that the solid crystal melts and becomes an intermediate state, not a solid crystal or a liquid, before it becomes a liquid, and when light is emitted or an electric or magnetic field is added, it exhibits birefringence peculiar to optical anisotropic crystals, Both properties of liquid and crystal are shown.

The LCD is largely manufactured through an array process, a color filter process, a liquid crystal cell process, and a module process.

The array process is a process of fabricating an array of thin film transistors (abbreviated as TFTs) on a first substrate (first substrate) by repeating deposition, photolithography, and etching processes. In the color filter process, a black matrix is formed on the second substrate so that light is shielded in portions other than the pixel region, and red, green, and blue colors are formed using dyes or pigments. After manufacturing a color filter, it is a process of forming the indium tin oxide (ITO) film for common electrodes.

In addition, the liquid crystal cell process is bonded to maintain a constant cell gap between the first substrate on which the thin film transistor forming process is completed and the second substrate on which the color filter process is completed, and injects liquid crystal between the first and second substrates to form an LCD cell. The module process is a process of manufacturing a circuit part for signal processing, connecting the panel of the thin film transistor liquid crystal display device and the signal processing circuit part with each other through mounting technology, and then attaching a mechanism to produce a module.

Here, the conventional liquid crystal cell process will be described in more detail as follows.

First, a cassette (not shown) on which a plurality of first substrates are loaded and a cassette (not shown) on which a plurality of second substrates are loaded are respectively loaded to each port by a loader. It is seated.

Here, a plurality of liquid crystal display panels are designed on the first substrate and the second substrate, and a plurality of gate lines arranged in one direction with a predetermined interval on the first substrate corresponding to each panel, and A plurality of thin film transistors and pixel electrodes respectively formed in a plurality of data lines arranged at regular intervals in a direction perpendicular to each gate line and in a matrix pixel region defined by the gate lines and the data lines. Are formed. In addition, a black matrix layer, a color filter layer, a common electrode, and the like are formed on the color filter substrate corresponding to each panel to block light in portions except the pixel region.

Next, the first substrate and the second substrate are selected using a robot arm programmed to select one of the plurality of first substrates and the plurality of second substrates, respectively.

Next, as shown in FIG. 1, after the alignment material is applied to each of the panels on the selected first and second substrates, an alignment process 1S is performed so that the liquid crystal molecules have uniform orientation. The alignment step (1S) proceeds in order of washing before application of the alignment film, alignment film printing, alignment film firing, alignment film inspection, and rubbing process.

Next, a gap process proceeds after the orientation process 1S. The gap process cleans the first substrate and the second substrate (2S), and then spreads a spacer (S) for maintaining a cell gap constant on the first substrate (3S), and the second substrate. After applying a seal material having a liquid crystal inlet (4S) to the outer periphery of each panel (4S), the pressure is applied to the first substrate and the second substrate and bonded together (5S).

Then, the bonded first substrate and the second substrate are cut and processed for each unit liquid crystal panel (6S).

Thereafter, liquid crystal is injected into each of the unit liquid crystal panels processed as described above through the liquid crystal inlet, and then the liquid crystal inlet is sealed (7S).

Next, the cut surface of each unit liquid crystal panel is polished, and the liquid crystal display device is manufactured by performing external appearance and electrical defect inspection 8S.

Here, the liquid crystal injection process is as follows.

When injecting the liquid crystal material, the liquid crystal material is first contained in a container, and then the container is placed in a chamber and the pressure in the chamber is kept in a vacuum state to remove moisture from the liquid crystal material or the inner wall of the container and remove bubbles. Defoaming.

Subsequently, the liquid crystal inlet of the empty liquid crystal cell is immersed in or contacted with the liquid crystal material while maintaining the pressure in the chamber in a vacuum state, and then the pressure in the chamber is increased from the vacuum state to the atmospheric pressure state. By the liquid crystal material is injected through the liquid crystal inlet.

However, the conventional method of manufacturing a liquid crystal display device by the liquid crystal injection method has the following problems.

First, after cutting into a unit panel, the liquid crystal injection hole is immersed in the liquid crystal liquid by maintaining the vacuum state between the two substrates, so that the liquid crystal injection takes a lot of time, the productivity is reduced.

Second, in the case of manufacturing a large-area liquid crystal display device, when the liquid crystal is injected by the liquid crystal injection method, the liquid crystal is not completely injected into the panel, which causes a defect.

Third, since the process is complicated and time-consuming as described above, several liquid crystal injection equipment is required, which requires a lot of space.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and a liquid crystal capable of rapidly measuring the liquid crystal dropping amount of a liquid crystal syringe dropping a liquid crystal directly on a large area glass substrate including at least one unit liquid crystal panel, thereby significantly reducing the process time. It is an object of the present invention to provide a method for manufacturing a display device.

According to an aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, the method comprising: providing liquid crystal containers mounted on a plurality of heads and liquid crystal containers as many as the number of liquid crystal syringes; And measuring the liquid crystal dropping amount while discharging the liquid crystal amount per shot from the plurality of liquid crystal syringes to the liquid crystal containers.

1 is a manufacturing flowchart of a liquid crystal display device to which a conventional vacuum injection method is applied.

2 is a perspective view for explaining a liquid crystal dropping method according to the present invention.

3 and 4 are a manufacturing flowchart of the liquid crystal display device according to the present invention.

5 is a perspective view for explaining a liquid crystal dispensing apparatus according to the present invention.

Explanation of symbols on the main parts of the drawings

60: substrate 65: liquid crystal

70: stage 100: liquid crystal dispensing device

102 liquid crystal syringe 104 head

106: measuring vessel 108: robot arm

110: digital scales

In order to overcome the shortcomings of the conventional liquid crystal injection method such as the liquid crystal dipping method or the liquid crystal vacuum injection method, a method proposed in recent years is a liquid crystal layer forming method by the liquid crystal dropping method. The liquid crystal dropping method does not inject the liquid crystal by the pressure difference between the inside and the outside of the panel, but directly drops and dispenses the liquid crystal onto the substrate, and uniformly spreads the liquid crystal dropped by the bonding pressure of the panel. The liquid crystal layer is formed by distribution. Since the liquid crystal dropping method directly drops the liquid crystal onto the substrate for a short time, the liquid crystal layer formation of the large area liquid crystal display device can be performed very quickly, and only the required amount of liquid crystal is directly dropped onto the substrate. Since it is possible to minimize the consumption of the liquid crystal display device has the advantage that can significantly reduce the manufacturing cost.

2 is a view showing a basic concept of the liquid crystal dropping method. As shown in the drawing, in the liquid crystal dropping method, before the lower substrate 105 and the upper substrate 103 on which the driving element and the color filter are formed, respectively, the liquid crystal 107 is dropped onto the lower substrate 105. Dropping The liquid crystal 107 may be dropped on the substrate 103 on which the color filter is formed. In other words, the substrate to be the liquid crystal dropping method in the liquid crystal dropping method can be either a TFT substrate or a CF substrate. However, when the substrates are bonded, the substrate on which the liquid crystal is dropped must be placed at the bottom.

In this case, a sealing material 109 is applied to the outer region of the upper substrate 103 to apply pressure to the upper substrate 103 and the lower substrate 105 so that the upper substrate 103 and the lower substrate 105 are bonded together. At the same time, droplets of the liquid crystal 107 are spread out by the pressure to form a liquid crystal layer having a uniform thickness between the upper substrate 103 and the lower substrate 105. In other words, the biggest feature of the liquid crystal dropping method is that the liquid crystal 107 is previously dropped on the lower substrate before the panel 101 is bonded, and then the panel is bonded by the sealing material 109.

The method of manufacturing a liquid crystal display device using the liquid crystal dropping method has the following difference from the manufacturing method of the conventional liquid crystal injection method. In the conventional liquid crystal injection method, a large area glass substrate in which a plurality of panels are formed is separated into panel units, and liquid crystal is injected. In the liquid crystal drop method, a liquid crystal layer is formed by dropping a liquid crystal on a substrate in advance, and then a glass substrate is paneled. Processing can be separated in units. This process difference provides many advantages when manufacturing an actual liquid crystal display device. Of course, there is an advantage of the liquid crystal dropping method itself (that is, the advantage of the rapid generation of the liquid crystal layer), but there is also an advantage resulting from forming the liquid crystal layer by the glass substrate unit formed with a plurality of panels. For example, when four liquid crystal panels are formed on a glass substrate, in the process of forming the liquid crystal layer by the liquid crystal injection method, the same conditions (the same liquid crystal container, the same injection) are injected when the liquid crystal is injected into each of the processed four liquid crystal panels at once. The liquid crystal panel having the same cell gap can be formed by a pressure or the like, but in the liquid crystal dropping method, a liquid crystal panel having different cell gaps can be formed by controlling the amount of liquid crystal dropped on the four liquid crystal panels by one drop. Will be.

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

3 and 4 are flowcharts illustrating a method of manufacturing a liquid crystal display device of the present invention, and FIG. 5 is a perspective view for explaining a liquid crystal dropping amount determination method during liquid crystal dropping.

First, although not shown, a first substrate and a second substrate on which an array process and a color filter process are performed are provided. The first substrate and the second substrate include a plurality of first unit substrates (called "TFT unit substrates") and a second unit substrate (referred to as "color filter unit substrates"), respectively, the array process and When the color filter process is completed, it is loaded in the first cassette and the second cassette, respectively.

The first cassette and the second cassette are mounted to the loader of the liquid crystal cell processing line by a transfer device. Here, the TFT unit substrate region includes a plurality of gate lines arranged in one direction at a predetermined interval by the array process, and a plurality of data lines and gate lines arranged at regular intervals in a direction perpendicular to the gate lines. And a plurality of thin film transistors and pixel electrodes respectively formed in a matrix pixel area defined by a data line.

In addition, the color filter unit substrate region includes a black matrix layer, a color filter layer, a common electrode, and the like, for blocking light in portions other than the pixel region.

The manufacturing process of the liquid crystal cell process under the above conditions is as follows.

The line which advances a liquid crystal cell process consists of a line which advances an alignment process, a gap process, and an inspection process. The alignment process includes washing before applying the alignment film, alignment film printing, firing, inspection, and rubbing processes, and the gap process includes washing after rubbing, liquid crystal dropping, sealing material coating, vacuum bonding, and curing processes. The process consists of a scribe / break process, a polishing process, and an inspection process of a unit liquid crystal panel.

First, the first and second cassettes for loading the first substrate and the second substrate, respectively, are placed in a loader of a line for performing the alignment process when entering the liquid crystal cell process.

Next, an alignment process line is selected by selecting a first substrate loaded in the first cassette and a second substrate matching the first substrate by a robot arm that recognizes information of the first and second cassettes mounted on the loader. Load in

The alignment process line includes a first process line for loading a first substrate and a second process line for loading a second substrate.

As shown in FIG. 3, the alignment process proceeds in the order of cleaning the alignment film before application (20S), alignment film application (21S), alignment film firing (22S), inspection (23S), and rubbing (24S).

When the alignment process is completed, the first substrate and the second substrate are loaded in the third and fourth cassettes provided in the unloader, respectively, and the substrates in which the defects occur during the alignment process, such as orientation defects, rubbing defects, and The defective substrate generated due to other causes is loaded into the buffer cassette provided on the side of the unloader.

Next, the third and fourth cassettes are loaded in a loader of a line that undergoes a gap process.

As shown in FIG. 4, one of the first and second substrates loaded in the third and fourth cassettes is selected and loaded into a line in which a gap process is performed.

Next, the selected first and second substrates are cleaned 25S, and then the first substrate is loaded into an LC dispensing apparatus, and the second substrate is sealed with an silver dispensing apparatus. (Seal) Loaded sequentially into the dispensing device.

Thereby, silver (Ag) dot shape is apply | coated 26S on a 2nd board | substrate, and the seal material is apply | coated to the periphery of each color filter unit board area | region (27S). At this time, the sealing material is light or thermosetting resin.

Meanwhile, a process of dropping 28S the liquid crystal onto the TFT unit substrate region corresponding to the seal material inner region on the color filter unit substrate region is performed.

Looking at the step (28S) of the liquid crystal proceeds as follows.

First, the liquid crystal is defoamed under vacuum, and then the liquid crystal dropping device is assembled / set and mounted on the liquid crystal dispensing device. Then, the liquid crystal dropping amount per shot is measured in order to test the adequacy of the assembly / setting of the liquid crystal dropping device.

FIG. 5 is a perspective view schematically illustrating an apparatus for measuring a liquid crystal drop amount according to the present invention, in which a plurality of liquid crystal syringes 102 are used to drop liquid crystal into the liquid crystal dispensing apparatus 100. Is mounted on the lower side of the liquid crystal syringe 102, and as many measuring containers 106 as the number of the liquid crystal syringes 102 are supported by the robot arm 108, and the lower portion of the measuring container as many as that number. Digital scales 110 are arranged. In addition, the substrate 60 is loaded on the stage 70 of the process line.

Although not shown, a display unit capable of monitoring the liquid crystal dropping amount is disposed at an outer side of the liquid crystal dispensing device 100 so that the liquid crystal dropping amount can be measured by an operator outside the liquid crystal dispensing device.

That is, the apparatus for measuring the amount of liquid crystal drop according to the present invention can accurately measure the amount of liquid crystal dropped in the liquid crystal syringe 102 using the digital scale 110. Using the apparatus for measuring the amount of liquid crystal drop according to the present invention as described above is a method for measuring the exact amount of the liquid crystal dropped in the liquid crystal syringe.

First, when a certain amount, for example, 100 shots of the liquid crystal 65 is discharged onto the substrate 60 from each of the plurality of liquid crystal syringes 102, the digital scale underneath it. The dripping amount is measured on the display unit by the meter. If the displayed liquid crystal amount is outside the predetermined (eg, ± 1%) error range of the preset liquid crystal amount, the liquid crystal syringe 102 is assembled and set and inspected so that the liquid crystal amount falls within the error range.

In the inspection process, if the liquid crystal amount of the liquid crystal syringe 102 set in advance is within an error range of the predetermined liquid crystal amount, the measurement container 106 in which the liquid crystal of the liquid crystal syringe 102 is contained and the discharge opening and closing of the liquid crystal are controlled. It can be judged that the assembly and setting state of the part and the like are good.

Such a liquid crystal amount measuring method can significantly shorten the process time because the liquid crystal dropping amount is measured simultaneously compared to the method of measuring the dropping amount of each liquid crystal dropping device one by one using a conventional robot arm.

Then, in the liquid crystal display device manufacturing method of the present invention, the first substrate is loaded into the liquid crystal dispensing apparatus, and the liquid crystal is dropped by using the set liquid crystal syringe 102. The liquid crystal dropping is uniformly doping the predetermined liquid crystal in a constant pitch (inside the pixel region) is coated with a frame-shaped sealing material on the liquid phase first substrate.

Next, as shown in FIG. 4, each of the first and second substrates subjected to the above process is loaded into a vacuum chamber so that the dropped liquid crystal is uniformly filled in each panel. Then, the seal material is cured to form a panel (30S).

Next, although not shown, a process of cutting the panel into unit panels is performed. The cutting process is in close contact with the panel of the glass material at a constant pressure through a cutting wheel (Wheel) to form a groove of a constant depth, and after the groove is formed in the panel cracks (Crack) downward through an external impact A plurality of unit panels are formed by cutting the panels to propagate. Subsequently, each cut unit panel is transferred to a polishing apparatus to polish the surface of the unit panel, and then final inspection of the appearance and electrical connection of the unit panel is completed to complete the liquid crystal cell process.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

The manufacturing method of the liquid crystal display device of the present invention described above has the following effects.

First, the liquid crystal dropping device is provided on the lower side of the liquid crystal dropping device as many as the number of the liquid crystal dropping device, and the number of digital scales are arranged in the lower portion of the liquid crystal container and the liquid crystal dropping amount is measured, thereby using the conventional robot arm. Compared to the method of measuring the dropping amount of each liquid crystal dropping device one by one, the process time can be considerably shortened because the liquid crystal dropping amount is simultaneously measured.

Second, since the liquid crystal is directly dropped onto the substrate for a short time by using the liquid crystal dropping method, the liquid crystal layer formation of the large area liquid crystal display device can be performed very quickly, and only the required amount of liquid crystal is directly deposited on the substrate. Since the dropping can minimize the consumption of the liquid crystal has the advantage that can significantly reduce the manufacturing cost of the liquid crystal display device.

Claims (4)

Providing liquid crystal syringes mounted on a plurality of heads, and as many liquid crystal containers as the number of liquid crystal syringes; And measuring the liquid crystal dropping amount while discharging the liquid crystal amount per shot from the plurality of liquid crystal syringes to the liquid crystal containers. The method of claim 1, And measuring the amount of liquid crystal dropping by using a digital balance meter as many as the number of liquid crystal containers. The method of claim 1, And monitoring the data of the measured amount of liquid crystal to determine whether the assembly and setting state of the liquid crystal syringe are defective. The method of claim 3, The determination of whether the defect is determined by comparing a preset value of the amount of liquid crystal per shot of the liquid crystal to be discharged with data of the amount of liquid crystal discharged to the liquid crystal container.