KR20040017501A - Liquid crystal display device having optimum spacer and method for fabricating liquid crystal display device using the same - Google Patents

Abstract

PURPOSE: A liquid crystal display having optimized spacers, and a method for manufacturing a liquid crystal display thereof are provided to prevent a liquid crystal unfilled area and damage of a substrate or spacers in dropping liquid crystal by optimizing a height and a unit area of a spacer. CONSTITUTION: A plurality of spacers(200) are formed on the top side of a first electrode(140) in a first height(H1). Each spacer has a first end part(210) contacting with the first electrode and a second end part(220) opposite to the first end part. The first height is higher than a permitted liquid crystal cell gap, wherein the first height is compressed under a first compression rate by a first pressure applied to the second end part, thereby compressing the first height to a second height(H2) lower than the permitted liquid crystal cell gap in calculating a unit area.

Description

Liquid crystal display device having optimized spacer and method for manufacturing liquid crystal display device thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having an optimized spacer and a method of manufacturing the liquid crystal display device thereof, and more particularly, by optimizing the height and unit area of a spacer for maintaining a cell gap. Liquid crystal display device having a liquid crystal unfilled area where the liquid crystal is not completely filled in the cell gap and an optimized spacer which prevents the substrate from being damaged by the pressing force by the spacer and a method of manufacturing the liquid crystal display device It is about.

In general, liquid crystals are positioned between TFT substrates and color filter substrates, which are manufactured through different manufacturing processes.

The liquid crystal is affected by the electric field formed between the TFT substrate and the color filter substrate. Specifically, the liquid crystal changes the transmittance of light supplied from the outside according to the electric field.

There is a cell gap between the TFT substrate and the color filter substrate for allowing the liquid crystal to be accommodated. This cell gap is only a few micrometers, and the large and small of the cell gap depends on the inherent characteristics of the liquid crystal. For example, the TN mode liquid crystal has a cell gap of about 4.6 μm.

In the conventional method of supplying liquid crystal to a cell gap of only a few μm, first, a liquid crystal display panel having a cell gap is partially contained in a barrel containing liquid crystal. Subsequently, a vacuum pressure is formed inside the cell gap, so that the liquid crystal is sucked up into the cell gap where the pressure is lowered.

As such, the liquid crystal injection method using vacuum pressure has an advantage of filling all liquid crystals without empty space inside a cell gap of only a few μm. On the other hand, the liquid crystal injection method using a vacuum pressure has a disadvantage that more liquid crystal is supplied into the cell gap than the desired liquid crystal amount.

Therefore, the liquid crystal injection method using the vacuum pressure is a press process for discharging the liquid crystal excessively injected into the cell gap reversely in addition to the process of injecting the liquid crystal into the cell gap, and after the liquid crystal is injected into the liquid crystal injection hole as a separate sealing material Incidentally, a liquid crystal sealing process for sealing, a cleaning process for cleaning the liquid crystal deposited on the outer surface of the liquid crystal display panel, and the like are additionally required.

Recently, a method of supplying liquid crystals by drop filling has been developed in addition to a liquid crystal injection method using vacuum pressure.

The dropping method liquid crystal supply method is completed by dropping a liquid crystal in a state where a spacer is formed on a color filter substrate and then bonding the liquid crystal onto a TFT substrate and a color filter substrate.

Such a drop type liquid crystal supply method has a simple process compared to the vacuum type liquid crystal injection method described above. On the other hand, the dropping liquid crystal supply method has another problem that bubbles are generated inside the liquid crystal display panel or the liquid crystal overflows.

For example, when more liquid crystal is supplied than the required amount, the excess liquid crystal overflows to the outside in the process of bonding the TFT substrate and the color filter substrate. On the contrary, when the liquid crystal is supplied less than the required amount, an un-filled area in which the liquid crystal does not exist inside the liquid crystal display panel is generated. The unfilled region greatly reduces the display characteristics of the liquid crystal display.

1 is a conceptual diagram illustrating a spacer applied to a conventional liquid crystal display device.

Referring to FIG. 1, a liquid crystal accommodating wall 20 is formed at an edge of the color filter substrate 10 to accommodate liquid crystal. Spacers 30 are formed inside the liquid crystal storage wall 20. The spacer 30 formed inside the liquid crystal accommodating wall 20 is formed by the patterned photoresist thin film.

2 is a conceptual diagram illustrating the injection of liquid crystal into a liquid crystal storage wall in which a spacer is conventionally formed.

Referring to FIG. 2, the dispenser 40 drops and fills the liquid crystal 50 into the liquid crystal storage wall 20. At this time, the amount of liquid crystal 50 filled in the inner space of the liquid crystal storage wall 20 and the height and area of the spacer 30 are very important.

3 is a conceptual diagram illustrating that a liquid crystal overflows in a conventional liquid crystal display.

Referring to FIG. 3, when the TFT 30 is aligned with the color filter substrate 10 in which the spacer 30 is formed and the liquid crystal 50 is injected, the TFT substrate 60 is formed by the atmospheric pressure P _atm . 30 will be pressurized.

At this time, when the liquid crystal 50 is excessively supplied from the dispenser 40 shown in FIG. 2 or the height and area of the spacer 30 are not optimized, between the color filter substrate 10 and the TFT substrate 60. The liquid crystal runs out or overflows.

For example, when the height and area of the spacer 30 are too small, a portion of the liquid crystal 50 dropped in the inner space of the liquid crystal storage wall 20 overflows while the spacer 30 is compressed much by atmospheric pressure. . The overflowed liquid crystal 55 contaminates the peripheral equipment and the liquid crystal display device and causes expensive liquid crystal to be wasted.

In addition, when the spacer 30 is compressed too much, the pressing force P ₂ for pressing the color filter substrate 10 by the spacer 30 may be excessively large and the color filter substrate 10 may be damaged.

4 is a conceptual diagram illustrating an unfilled region formed due to lack of liquid crystal in a conventional liquid crystal display.

Referring to FIG. 4, when the amount of liquid crystal is insufficient, or when the height and area of the spacer 30 are too large, the liquid crystal 50 is not filled between the TFT substrate 60 and the color filter substrate 10. Region 55 is generated. In the unfilled region 55, the display is impossible since the liquid crystal 50 is not normally arranged by the electric field.

In order to overcome this problem, the height and area of the spacer 30 may be precisely calculated or the amount of liquid crystal may be precisely calculated. However, it is very difficult to accurately calculate the required volume or the amount of liquid crystal of the actual spacer 30.

The reason is that as shown in FIG. 3 or 4, the TFT substrate 60 presses the spacer 30 by atmospheric pressure, and the spacer 30 is compressed by the atmospheric pressure and the weight of the TFT substrate 60.

In addition, since the bottom surface of the TFT substrate 60 is not flat by a thin film transistor, a pixel electrode, or the like, it is difficult to accurately calculate the volume to which the actual liquid crystal is supplied, making it difficult to accurately calculate the amount of liquid crystal.

For this reason, it has been difficult to supply liquid crystals by the dropping method in the liquid crystal display device up to now, and liquid crystals are injected in a vacuum injection method having a large number of processes and a very small amount of liquid crystal consumption.

However, in recent years, as the size of the liquid crystal display device is gradually increased, there are limitations in the vacuum injection method, and efforts to supply the liquid crystal using the dropping method have been continuously performed. In order to supply liquid crystal between the color filter substrate and the TFT substrate in a dropping manner, it is necessary to optimize the spacer and the amount of liquid crystal.

Accordingly, the first object of the present invention is to meet the above conventional requirements, and the first object of the present invention is to prevent the unfilled region caused by the lack of liquid crystal in the process of supplying the liquid crystal in a dropping manner. Of course, there is provided a liquid crystal display device having an optimized spacer that prevents even the substrate damage caused by the spacer.

The second object of the present invention is to meet such a conventional demand. The second object of the present invention is to prevent the unfilled region due to lack of the liquid crystal in the process of supplying the liquid crystal in a dropping manner, as well as a spacer. The present invention provides a method of manufacturing a liquid crystal display device having an optimized spacer which prevents even the damage of the substrate.

1 is a conceptual diagram illustrating a spacer applied to a conventional liquid crystal display device.

2 is a conceptual diagram illustrating the injection of liquid crystal into a liquid crystal storage wall in which a spacer is conventionally formed.

3 is a conceptual diagram illustrating that a liquid crystal overflows in a conventional liquid crystal display.

4 is a conceptual diagram illustrating an unfilled region formed due to lack of liquid crystal in a conventional liquid crystal display.

5 is a cross-sectional view of a liquid crystal display device according to a first embodiment of the present invention.

6 is a plan view illustrating a first substrate of a liquid crystal display according to a first embodiment of the present invention.

7 is a cross-sectional view taken along the line A-A of FIG.

FIG. 8A is a graph simulating the change of the cell gap of the liquid crystal relative to the unit area of the spacer according to the first embodiment of the present invention.

8B is a graph simulating a change in compression ratio of a spacer relative to a unit area of the spacer according to the first embodiment of the present invention.

FIG. 9A is a graph illustrating a cell gap change and a compression ratio of a liquid crystal with respect to a unit area in a state where an elastic modulus is lowered according to a first embodiment of the present invention.

9B is a graph showing the cell gap change and the compression ratio of the liquid crystal with respect to the unit area in the state where the modulus of elasticity is increased according to the first embodiment of the present invention.

10 is a plan view showing a second substrate of the liquid crystal display according to the first embodiment of the present invention.

FIG. 11A is a process diagram illustrating a chromium thin film formed on a transparent substrate according to a second embodiment of the present invention. FIG.

11B is a flowchart illustrating a photoresist thin film patterned on a chromium thin film according to a second embodiment of the present invention.

11C is a plan view of a pattern mask for patterning a chromium thin film according to a second embodiment of the present invention.

FIG. 11D is a cross-sectional view taken along the line C-C of FIG. 11C showing that a black matrix is manufactured by patterning a chromium thin film according to a second embodiment of the present invention.

FIG. 11E is a flowchart illustrating the formation of a color filter and a first electrode on a black matrix according to a second embodiment of the present invention.

FIG. 11F is a process diagram showing a spacer forming thin film for forming a spacer on an upper surface of a first electrode according to a second embodiment of the present invention.

FIG. 11G is a plan view of the pattern mask of FIG. 11F.

FIG. 11H is a flowchart illustrating the dropping of liquid crystal onto a first substrate having spacers according to a second embodiment of the present invention.

FIG. 11I is a cross-sectional view showing a tapered end portion according to a second embodiment of the present invention. FIG.

11J is a cross-sectional view illustrating a second substrate assembled to a first substrate according to a second embodiment of the present invention.

In order to realize the first object of the present invention, the present invention provides a transparent substrate, a black matrix having a lattice shape, a color filter formed in an inner region formed by the black matrix, and a first power formed so that a reference power is applied to the entire area of the transparent substrate. A first substrate comprising an electrode, a first end formed above the black matrix among the first electrodes, a second end formed at a first height above the allowable liquid crystal cell gap from the first end, and a first applied to each second end Spacer having a unit area for compressing the first height below the first compression ratio by a pressure to a second height smaller than the allowable liquid crystal cell gap, and a liquid crystal filled up to the height of the allowable liquid crystal cell gap in the first substrate on which the spacer is formed. And a second electrode facing the color filters on the substrate and the substrate applying the first pressure to the second end and receiving the pixel voltage. There is provided a liquid crystal display device having an optimized spacer including a second substrate having the same.

Furthermore, in order to realize the second object of the present invention, the present invention calculates a first height of a spacer having a height greater than or equal to the allowable liquid crystal cell gap, and the first height is compressed to be less than or equal to the first compression ratio by the first pressure to allow the allowed liquid crystal cell. Calculating a unit area of the spacer compressed to a second height smaller than the gap, forming a black matrix having a lattice shape on the transparent substrate, forming a color filter on an inner region formed by the black matrix, and a reference power source over the entire surface of the transparent substrate Forming a first electrode to be applied and forming a spacer on an upper surface of the first electrode corresponding to the upper part of the black matrix by the first height and the unit area to manufacture the first substrate, and the acceptable liquid crystal cell on the first substrate. Filling the liquid crystal to the height of the gap; forming second electrodes facing the color filters on the substrate and configured to receive pixel voltages; 2. A method of manufacturing a liquid crystal display device, the method comprising: manufacturing a substrate and assembling the first substrate and the second substrate such that the spacer is compressed to an allowable liquid crystal cell gap by a first pressure.

According to the present invention, the height and unit area of the spacer are optimized to prevent the liquid crystal unfilled region from being generated in the liquid crystal display device by the spacer and to prevent the first and second substrates or the spacer itself from being damaged by the spacer.

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

<Example 1>

5 is a cross-sectional view of a liquid crystal display device according to a first embodiment of the present invention.

Referring to FIG. 5, the liquid crystal display 500 may include a first substrate 100, a spacer 200, a liquid crystal 300, and a second substrate 400.

6 is a plan view illustrating a first substrate of a liquid crystal display according to a first embodiment of the present invention.

5 or 6, the first substrate 100 includes a transparent substrate 110, a black matrix 120, a color filter 130, a first electrode 140, and a liquid crystal sealing wall 150. .

The transparent substrate 110 serves as a base for supporting the black matrix 120, the color filter 130, and the first electrode 140.

The black matrix 120 is formed by applying and patterning a chromium (Cr) or chromium oxide layer (CrO ₂ ) material having high light absorption over the entire surface of the transparent substrate 110. In this case, the black matrix 120 is formed in a lattice shape on the transparent substrate 110. Referring to FIG. 5, the black matrix 120 prevents light leakage between the pixel electrode and the pixel electrode of the second substrate 400.

One color filter 130 is formed for each inner region surrounded by the black matrix 120 having a lattice shape. The color filter 130 includes a red color filter 132 through which light of a red wavelength passes, a green color filter 134 through which a green wavelength light passes, and a blue color filter 136 through which a blue wavelength light passes. It consists of. The edge of the color filter 130 is formed on the black matrix 120.

Referring to FIG. 5, the first electrode 140 is formed over the entire surface of the transparent substrate 110 to cover the color filter 130. The reference voltage is applied to the first electrode 140.

7 is a cross-sectional view taken along the line A-A of FIG.

6 or 7, the spacers 200 are formed at a first height H ₁ on the upper surface of the first electrode 140 corresponding to the upper portion of the black matrix 120 formed on the first substrate 100. do. In this case, the spacers 200 may have a cylindrical shape having a first end 210, a second end 220, and a circumferential surface. The first end 210 contacts the first electrode 140 of the spacer 200, and the second end 220 has a relationship facing the first end 210.

The first height H ₁ of the cylindrical spacers 200 is formed higher than the allowable liquid crystal cell gap indicated by the reference H ₂ . In contrast, when the first height H ₁ is set to be less than or equal to the allowable liquid crystal cell gap H ₂ , the spacers 200 lose the cell gap adjustment function.

In this case, forming the first height H ₁ of the spacers 200 higher than the allowable liquid crystal cell gap H ₂ is performed by the method illustrated in FIG. 5 in a state where the liquid crystal 300 is dropped on the first substrate 100. This is because the spacer 200 is compressed by the second substrate 400 when the two substrates 400 are combined, thereby reducing the first height H ₁ .

In this case, the compression amount of the spacers 200 is closely related to the unit area, the number, and the elastic modulus of each spacer 200.

Once the elastic modulus is not considered, the compression amount of the spacers 200 is determined by the unit area and the number of each spacer 200.

First, the spacers 200 are formed on the first electrode 140 corresponding to the upper portion of the black matrix 120 in a number corresponding one to one to the number of the color filters 130. This is to determine the unit area of each spacer 200. Once the unit area of each spacer 200 is determined, the number of spacers may be arbitrarily adjusted in consideration of the unit area of the spacer.

At this time, if the unit area of the spacer 200 is too small and the spacer 200 is compressed too much, the spacer 200 exerts an excessive force on the first substrate 100. Accordingly, the first electrode 140 of the first substrate 100 may be damaged, the black matrix 120 may be broken, and the spacer 200 itself may be damaged.

On the contrary, if the unit area of the spacer 200 is too large and the spacer 200 is compressed a little, the liquid crystal 300 is not filled between the first substrate 100 and the second substrate 400 shown in FIG. 5. An un-filled area may be generated. The unfilled area causes a fatal defect in a display using liquid crystals.

As described above, if the compression amount of the spacer 200 is too large or too small, a fatal defect may occur, so the unit area of the spacer 200 should be considered very carefully and precisely.

Hereinafter, a method of calculating the unit area of the spacer will be described.

The unit area of the spacer 200 is calculated by computer simulation. In order to calculate the unit area of the spacer, a comparison panel is required.

In one embodiment, the comparison panel is a color liquid crystal display panel having 17 inch SXGA resolution. The comparison panel has a color filter area of 88 x 264 mu m (the color filter area and the pixel area are almost similar). The width of the black matrix in the comparison panel is 12 to 32 µm, and one spacer is formed per twelve color filters in the comparison panel. In the comparison panel, the area of the spacer formed by one per twelve color filters is about 500 mu m ² , and the spacer has a diameter of 25 mu m and has a cylindrical shape. At this time, the elastic modulus of the spacer in the comparison panel is 487 N / mm 2.

In order to form a spacer per one color filter in the comparison panel having such a specification, the area of one spacer formed per 12 color filters is divided by 500 μm ^ 2 by the number of color filters, which is about 41.6 μm ² . . At this time, 41.6 μm ² is the “unit area” of the spacer in which one is formed per one color filter.

By the specification of the comparison panel, the unit area of the spacer to be formed in the liquid crystal display panel larger than the comparison panel can also be determined.

For example, the "unit volume" of the spacer in a color liquid crystal display panel (hereinafter referred to as an experiment panel) having a 40-inch XGA resolution is calculated as follows.

In Equation 1, A is the unit area of the spacer, and the coefficient a is Where B is the spacer area formed per n color filters and C is the number of spacers formed per n color filters. For example, if there is one spacer formed per twelve color filters, C is numerically to be. At this time, the modulus of elasticity of the spacer is 487 N / mm 2.

At this time, in Equation 1, B and C always have a constant value. For example, as B increases, C decreases, and when B decreases, C increases.

Specifically, the coefficient a is a coefficient for compensating for the area difference between the comparison panel and the experiment panel. Specifically, the coefficient a is 1 when the color filter area of the test panel is the same as the color filter area of the comparison panel.

On the other hand, when the color filter area of the test panel is larger than the color filter area of the comparison panel, the coefficient a is smaller than 1, and when the color filter area of the test panel is smaller than the color filter area of the comparison panel, the coefficient a is larger than 1. .

In this case, when the coefficient a is smaller than 1, the unit area of the spacer is reduced, and when the coefficient a is larger than 1, the unit area of the spacer is increased.

For example, in an experimental panel having a size of 40 inches, when the area of the color filter is 227 × 681 μm and the area of the comparison panel color filter is 88 × 264 μm, the coefficient a ₄₀ is to be. Calculating this, a ₄₀ is about 0.15. In other words, the experimental area should increase the unit area of the spacer.

B of Equation 1 is the area of one spacer formed for each of the n color filters formed on the black matrix. In the experiment panel, the area that the spacer can have is formed in a black matrix having a width of 30 to 45 μm with a diameter of about 35 μm, so B is It becomes about 800 micrometer <^2> by the formula (D = 35 micrometer). The diameter of the spacer does not become larger than the width of the black matrix.

In Equation 1, C is set to the size of the area of the color filter of the comparison panel and the experiment panel, and the area of the color filter of the experiment panel is about four times larger than the area of the color filter of the comparison panel. By This is appropriate.

Through such a process, when the coefficients a, B, and C are determined in Equation 1, the unit area of the spacer formed one per color filter in the test panel can be calculated.

For example, in an experimental panel having 40 inches, the coefficient a is 0.15, the area of the color filter per n pieces is 800 µm ² , and the number of spacers formed per n pieces is , 0.15 × 800 × It becomes about 40 micrometer <^2> by. That is, the unit area in the 40 inch test panel is 40 μm ² . In this way, if only the color filter area and the width of the black matrix are calculated at 15 inches, 17 inches, 20 inches, 40 inches, and 60 inches, the unit area can be calculated.

At this time, there is also a unit area which cannot be actually used in the unit area of the spacer calculated by Equation (1). If the unit area of the spacer is incorrectly selected without taking this into consideration, as described above, an un-filled region may occur or damage of the first substrate may occur.

In fact, the unit area of the spacer has to take into account the cell gap change of the liquid crystal generated when the first pressure is applied to the spacer from the outside. In order to observe the cell gap change of the liquid crystal, the unit area of the spacer is gradually increased at 0 μm ² . Further, the first pressure is set to be equal to the pressure applied to the second end of the spacer by the weight and atmospheric pressure of the first substrate to be described later.

When the first pressure is applied to the second end of the spacer, the cell gap of the liquid crystal is changed by the unit area of the spacer.

For example, if the unit area is increased, the cell gap will increase as the amount of compression of the spacer due to the first pressure decreases.

FIG. 8A is a graph simulating the change of the cell gap of the liquid crystal relative to the unit area of the spacer according to the first embodiment of the present invention.

Referring to the graph of FIG. 8A, as the unit area of the spacer gradually increases from 0 μm ² , the cell gap of the liquid crystal rapidly increases to about 30 μm ² and gradually increases after 30 μm ² . see.

As the unit area was continuously increased, the cell gap of the liquid crystal became 4.75 μm or more, which is the maximum allowable liquid crystal cell gap, when the unit area was 76 μm ² or more. This means that the spacer compressed by the first pressure does not coincide with the surface of the liquid crystal. That is, when the liquid crystal display panel is assembled in a state in which the unit area of the spacer is 76 μm ² or more, there is an unfilled region in which the liquid crystal is not filled in the liquid crystal display panel. The unfilled area is hatched in the graph of FIG. 8A.

According to the graph of FIG. 8A, when the unit area of the spacer is 76 μm ² or less, no unfilled region occurs. However, when the unit area of the spacer is too small to approach 0 μm ² , the second pressure applied by the spacer to the first substrate is gradually increased, and when the second pressure is too large, damage to the first electrode or the like of the first substrate is caused. Can give

To prevent this, the compression ratio of the spacer should be considered. As the actual compressibility of the spacer increases, the second pressure exerted on the first substrate also increases proportionally.

8B is a graph simulating a change in compression ratio of a spacer relative to a unit area of the spacer according to the first embodiment of the present invention.

Referring to the graph of FIG. 8B, as the unit area of the spacer approaches 0 μm ² , the compressibility of the spacer increases, and as the unit area of the spacer gradually increases, the compressibility of the spacer decreases rapidly.

Although slightly different for each spacer, the compressibility of the spacer having an elastic modulus of 487 N / mm 2 is a safe value that does not damage the first substrate and the spacer.

At this time, the compression rate of the spacer is 15% means that the spacer having a first height of 100㎛ in one embodiment is compressed to 85㎛. That is, the compressed spacer is 85% of the first height.

For this reason, if the unit area of the spacer where the compression ratio of the spacer is 15% or less is found in the graph, it is about 32 μm ² . That is, when the unit area of the spacer is 32 μm ² or less, damage to the first substrate or the spacer may occur.

For this reason, the cross-sectional area of the spacer is 32㎛ ^2, unloading can result in destruction of the first substrate or spacer is suitable for this region except over 76㎛ ² that can result in filter area. That is, the cross-sectional area of the spacer is, 32㎛ ² ≤ unit area ≤76㎛ ² (However, the modulus of elasticity 487 N / ㎟).

However, the optimized section of the unit area of the spacer is affected by the elastic modulus.

FIG. 9A is a graph illustrating a cell gap change and a compression ratio of a liquid crystal with respect to a unit area in a state where the modulus of elasticity is lowered according to the first embodiment of the present invention.

Referring to the graph of FIG. 9A, when the elastic modulus is lowered from 487 N / mm 2 to 243.5 N / mm ^2, the unit area of the spacer in which the un-fill area does not occur is 100 μm ² or more and about 120 μm ^{2, which} is much larger than 76 μm ^2. Is increased to a degree. In addition, the interval of the unit area whose compression ratio of the spacer with respect to the unit area of the spacer which does not cause damage to the first substrate or the spacer is 15% or less is 66 µm ² or more. That is, the unit area of the spacer, 66㎛ ² ≤ unit area ≤120㎛ ² or more (however, Young's modulus is 243.5 N / ㎟) a.

9B is a graph showing the cell gap change and the compression ratio of the liquid crystal with respect to the unit area in the state where the modulus of elasticity is increased according to the first embodiment of the present invention.

Referring to the graph of FIG. 9B, when the modulus of elasticity is increased from 487 N / mm 2 to 974 N / mm ^2, the unit area of the spacer where no unfilled region occurs is 40 μm ² or less, much smaller than 76 μm ² . In addition, the unit area whose compressibility of the spacer with respect to the unit area of the spacer which does not cause damage to the first substrate or the spacer is 15% or less is 18 µm ² . That is, the unit area of the spacer, 18㎛ ² ≤ unit area ≤40㎛ ² (However, the modulus of elasticity 974 N / ㎟) a.

According to the result, when the modulus of elasticity is changed, the ratio of the modulus of elasticity must be reflected in the unit area to calculate the correct unit area of the spacer.

At this time, the comparative elastic modulus in Equation 2 is 487 N / mm 2.

When the experimental modulus of elasticity is changed from 243.5 N / mm 2 to 974 N / mm 2 in Equation 2, the unit area of the spacer is about 18 μm ² minimum and about 120 μm ² maximum.

Referring to FIG. 7, the spacer 200 is formed on the upper surface of the first electrode 140 corresponding to the black matrix 120 by the unit area of the spacer selected as described above by the unit area and the first height.

In this case, one spacer may be formed in the spacer 200 corresponding to one color filter 130 of the first substrate 100. At this time, the area of the spacer is a unit area.

In contrast, one spacer 200 may be formed for every n color filters 130 formed on the first substrate 100. In this case, the area of the spacer 200 formed by one for each of the n color filters 130 may be multiplied by n times the unit area.

For example, when the spacers are formed in a number corresponding to the number of the color filters 130, assuming that the unit area of the spacer is A, the spacers 200 formed by 1 for each of the n color filters 130 are A × n. It has an area of twice as much.

Meanwhile, the liquid crystal 300 is dropped into the _first liquid crystal cell gap H ₂ shown in FIG. 7 by a dispenser or the like on the first substrate 100 on which the spacer 200 is formed based on the unit area of the spacer 200. Is filled.

10 is a plan view of a second substrate according to a first embodiment of the present invention.

Referring to FIG. 10, the second substrate 400 again includes a substrate 410, a thin film transistor (not shown), and a second electrode 420.

The substrate 410 is transparent in one embodiment. The second electrode 420 faces the color filter 130 formed on the first substrate 100, and a thin film transistor is connected to each second electrode 420.

The second electrode 420 formed on the second substrate 400 is bonded to be aligned with the color filter 130 of the first substrate 100 to manufacture the liquid crystal display 500.

<Example 2>

In a second embodiment of the present invention, a method of manufacturing a liquid crystal display device is disclosed.

In order to manufacture the liquid crystal display shown in FIG. 5 according to the second embodiment, calculating the first height H ₁ and the unit area of the spacer 200, the calculated unit area and the first area of the spacer 200. Forming a spacer 200 on the first substrate 100 at a height H ₁ , supplying the liquid crystal 300 to the first substrate 100, and supplying the second substrate 400 to the first substrate 100. ) Assembling).

First, the first height H ₁ of the spacer 200 is set to be at least equal to the allowable liquid crystal cell gap H _{2 of the} liquid crystal for performing display with the liquid crystal 300. The unit area of the spacer 200 is set such that the spacer 200 having the first height H ₁ may be compressed by the first pressure to be substantially in contact with the surface of the liquid crystal 300.

At this time, the "unit area" of the spacer 200 is an area when one spacer is formed in one color filter 130. When one spacer 200 is formed for every n color filters 130, the spacer 200 is formed by an area multiplied by n times the unit area.

The method of calculating the first height H ₁ and the unit area of the spacer 200 as described above in detail in the first embodiment will be omitted.

After the first height H ₁ and the unit area of the spacer 200 are calculated, a step of manufacturing the first substrate 100 is performed.

11A to 11J are process diagrams illustrating a method of manufacturing a first substrate according to a second embodiment of the present invention.

FIG. 11A is a process diagram illustrating a chromium thin film formed on a transparent substrate according to a second embodiment of the present invention. FIG.

Referring to FIG. 11A, a chromium thin film 125 is formed on one side of the transparent substrate 110 over the entire area. The chromium thin film 125 is formed by a chemical vapor deposition process or a sputtering process.

11B is a flowchart illustrating a photoresist thin film patterned on a chromium thin film according to a second embodiment of the present invention.

Referring to FIG. 11B, the photoresist thin film is applied to the upper surface of the chromium thin film 125 by spin coating or slit coating. Subsequently, the pattern mask 127 having a lattice pattern is aligned with the transparent substrate 110.

11C is a plan view of a pattern mask for patterning a chromium thin film according to a second embodiment of the present invention.

Referring to FIG. 11C, the pattern mask 127 is composed of a transparent glass substrate 128, a chrome pattern 129 patterned in a lattice shape on the glass substrate 128 to prevent light from passing through, and an opening 129a through which light passes. do.

Light is supplied toward the transparent substrate 110 from the upper portion of the pattern mask 127 having such a configuration. At this time, the light supplied to the chrome pattern 125 by the pattern mask 127 is blocked by the chrome pattern 129, and the light supplied to the opening 129a reaches the photoresist thin film through the opening 129a. .

The photoresist thin film in which the light supplied through the opening 129a has reached is removed by the developing process, and the photoresist thin film in which the light has not reached by the chromium pattern 129 remains without being removed by the shape process.

FIG. 11D is a cross-sectional view taken along the line C-C of FIG. 11C showing that a black matrix is manufactured by patterning a chromium thin film according to a second embodiment of the present invention.

Referring to FIG. 11D, a portion of the chromium thin film 125 that is not protected by the patterned photoresist thin film is etched through a dry etching process or a wet etching process to form a black matrix 120 having a lattice shape. Thereafter, the remaining photoresist thin film formed on the black matrix 120 is removed through an ashing process or the like.

FIG. 11E is a flowchart illustrating the formation of a color filter and a first electrode on a black matrix according to a second embodiment of the present invention.

Referring to FIG. 11E, the color filter 130 is formed in the inner region 121 of the black matrix 120 having a lattice shape. The color filter 130 is divided into a red color filter 132, a green color filter 134, and a blue color filter 136, and is formed by the red color filter 132, the green color filter 134, and the blue color filter ( Each edge of 136 overlaps the black matrix 120.

The first electrode 140 is formed on the top surface of the color filter 130 in a state where the black matrix 120 and the color filter 130 are formed on the transparent substrate 110. The first electrode 140 is formed of an indium tin oxide film or an indium zinc oxide film by chemical vapor deposition.

FIG. 11F is a process diagram showing a spacer forming thin film for forming a spacer on an upper surface of a first electrode according to a second embodiment of the present invention.

Referring to FIG. 11F, a thin film 210 for spacer formation having an elastic modulus of 487 N / mm 2 is formed on the top surface of the first electrode 110 by spin coating or slit coating. At this time, the spacer formation thin film 210 is formed to the first height (H ₁ ) calculated previously. At this time, the spacer formation thin film 210 is a photosensitive material that can be removed by reacting with light.

The pattern mask 220 is positioned on the upper surface of the spacer formation thin film 210 in a state where the spacer formation thin film 210 is formed on the upper surface of the first electrode 140.

FIG. 11G is a plan view of the pattern mask of FIG. 11F.

Referring to FIG. 11G, a spacer forming pattern 225 is formed in the pattern mask 220 to have the same area as the unit area of the spacer 220 calculated above.

Light is supplied from the pattern mask 220 to the spacer formation thin film 210 to remove all remaining portions of the spacer formation thin film 210 except for the portion where the spacer is to be formed, thereby manufacturing the spacer.

FIG. 11H is a flowchart illustrating the dropping of liquid crystal onto a first substrate having spacers according to a second embodiment of the present invention.

Referring to FIG. 11H, reference numeral 200 is a spacer. At this time, the spacer may be formed so that the end is tapered, as shown in FIG. In the state where the spacer 200 is formed on the first substrate 100, the liquid crystal 300 is dropped onto the first substrate 100 by the dispenser 310. At this time, the dropped liquid crystal is filled to have an acceptable liquid crystal cell gap H ₂ .

11J is a cross-sectional view illustrating a second substrate assembled to a first substrate according to a second embodiment of the present invention.

Referring to FIG. 11J, the second substrate 400 having the thin film transistor and the second electrode 410 is assembled to the first substrate 100 while the liquid crystal 300 is completely filled in the first substrate 100. The second substrate 400 applies a first pressure to the spacer 200 formed on the first substrate 100 so that the spacer 200 formed on the first substrate 100 fills the liquid crystal cell gap H ₂ . To a surface of 300).

As described above in detail, the height and unit area of the spacer may be optimized to prevent the liquid crystal unfilled region generated when the liquid crystal is supplied in the dropping manner and to prevent the breakage of the substrate or the spacer.

In the detailed description of the present invention described above with reference to a preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge in the scope of the invention described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

Claims (14)

A first substrate including a transparent substrate, a black matrix formed in a lattice shape on the transparent substrate, a color filter formed in an inner region formed by the black matrix, and a first electrode formed to apply a reference power to an entire area of the transparent substrate; A first end formed above the black matrix of the first electrodes, a second end formed at a first height greater than an allowable liquid crystal cell gap from the first end, and the first pressure applied to each second end. A spacer having a unit area such that one height is compressed to be less than or equal to a first compression rate to be compressed to a second height smaller than the allowable liquid crystal cell gap; A liquid crystal filled to the height of the allowable liquid crystal cell gap in the first substrate on which the spacer is formed; And And a second substrate having the first pressure applied to the second end and a second electrode facing the color filters on the substrate and having second electrodes for receiving a pixel voltage. The method of claim 1, wherein the unit area is the area coefficient of the color filter, the area of the spacer formed for every n color filters, the density of the spacer formed for every n color filters It is calculated by multiplying the liquid crystal display device. According to claim 2, wherein the area coefficient of the color filter The area of the spacer is calculated by the width of the black matrix, and the spacer density is calculated by the reference color filter area and the color filter area. The liquid crystal display of claim 1, wherein the spacer has a cylindrical shape, and the diameter of the spacer is equal to or less than a width of the black matrix. The liquid crystal display of claim 1, wherein the second end of the spacer is tapered. The liquid crystal display of claim 1, wherein the unit area decreases as the elastic modulus of the spacer increases. The liquid crystal display device according to claim 1, wherein the pressure exerted on the first substrate by the spacer while the spacer is compressed to an allowable compression cell gap is equal to or less than the breaking strength of the first substrate. The liquid crystal display device according to claim 1, wherein the allowable liquid crystal cell gap is 4.45 to 4.75 mu m. The unit area of claim 1, wherein the allowable liquid crystal cell gap is 4.45 to 4.75 μm, the first pressure is atmospheric pressure, and the elastic modulus of the spacer is 974 N / mm 2 to 243.5 N / mm 2. A liquid crystal display device, characterized in that between 120㎛ ² . The liquid crystal display of claim 1, wherein the compression ratio of the spacer is 15% or less, and the second height is 85% or more. Calculate a first height of a spacer having a height greater than or equal to an allowable liquid crystal cell gap, wherein the unit area of the spacer is compressed to be less than or equal to the first compression ratio by a first pressure to a second height smaller than the allowable liquid crystal cell gap Calculating; Forming a black matrix having a lattice shape on the transparent substrate, forming a color filter in an inner region formed by the black matrix, forming a first electrode formed to apply a reference power to the entire surface of the transparent substrate, and forming the first height and the Manufacturing a first substrate by forming a spacer on an upper surface of a first electrode corresponding to an upper portion of the black matrix by a unit area; Filling a liquid crystal to the first substrate to a height of the allowable liquid crystal cell gap; Manufacturing a second substrate facing the color filters on the substrate and on which second electrodes are formed to receive a pixel voltage; And And assembling the first substrate and the second substrate such that the spacer is compressed to the allowable liquid crystal cell gap by the first pressure. 12. The method according to claim 11, wherein in the step of calculating the unit area of the spacer, the allowable liquid crystal cell gap is 4.45 to 4.75 mu m, the first pressure is atmospheric pressure, and the elastic modulus of the spacer is 243.5 N / mm 2 to 974 N /. When the mm2, the unit area is 18 to 120㎛ ² manufacturing method of the liquid crystal display device. 12. The method of claim 11, wherein in the forming of the spacer, an end portion of the spacer is processed to be tapered. The method of claim 11, wherein the filling of the liquid crystal is performed by dropping the liquid crystal onto the first substrate from the upper portion of the first substrate.