KR20070047087A - Liquid crystal display and method for manufacturing the same - Google Patents

Abstract

The present invention provides a liquid crystal display and a method for manufacturing the same, by forming column spacers on a flat substrate using a mask having a circular slit, thereby preventing touch defects and pressed defects by varying the height of the column spacers for each region. The liquid crystal display of the present invention includes a first substrate on which a thin film transistor array is formed, a second substrate facing the first substrate, and a color filter array flat, and a first height on a predetermined portion on the second substrate. a first column spacer formed of (h1) and a second column spacer formed of a second height h2 spaced apart from the first column spacer on the second substrate and smaller than a height of the first column spacer; And a liquid crystal layer filled between the first substrate and the second substrate.

Protrusion, column spacer, bad touch, diffraction exposure mask, circular slit

Description

Liquid Crystal Display and Method for Manufacturing the Same

1 is a cross-sectional view showing a liquid crystal display device including a conventional column spacer.

2A and 2B are plan and cross-sectional views illustrating a touch failure of a liquid crystal display including a column spacer.

3 is a cross-sectional view illustrating a liquid crystal display including a general dual column spacer.

4 is a cross-sectional view of an LCD including a dual column spacer having a protrusion structure.

5 is a cross-sectional view showing a liquid crystal display of the present invention.

6 is a cross-sectional view of a liquid crystal display according to another exemplary embodiment of the present invention.

7A and 7B are plan views illustrating masks for forming a first column spacer and a second column spacer of the liquid crystal display of the present invention.

8A to 8D are plan views showing masks for forming the second column spacer of the present invention.

9A and 9B are plan views illustrating masks for forming a first column spacer and a second column spacer having a single circular slit, and a second column spacer formed using the liquid crystal display of the present invention. profile

10A and 10B illustrate a plan view of a mask for forming a first column spacer and a second column spacer having a plurality of circular slits and a second column spacer formed using the liquid crystal display according to the present invention. Profile shown

11 is a plan view showing a liquid crystal display of the present invention.

12A to 12C are cross-sectional views illustrating a column spacer forming process of a liquid crystal display of the present invention.

* Description of Symbols Representing Major Parts of Drawings *

100: first substrate 101: gate line

101a: gate electrode 102: data line

102a: source electrode 102b: drain electrode

103: pixel electrode 103a: first storage electrode

104: common electrode 104a: common line

104b: second storage electrode 105: gate insulating film

106: protective film 106a: contact hole

110: protrusion 150: liquid crystal layer

200: second substrate 201: black matrix layer

202: color filter layer 203: overcoat layer

204 photosensitive resin

210: first column spacer 220: second column spacer

300: mask 301: light shield

302: slit 305: opening

The present invention relates to a liquid crystal display, and in particular, by forming column spacers on a flat substrate using a mask having a circular slit, the height of the column spacers can be changed by region to prevent touch defects and deterioration defects. The present invention relates to a liquid crystal display device and a manufacturing method thereof.

As the information society develops, the demand for display devices is increasing in various forms, and in recent years, liquid crystal display devices (LCDs), plasma display panels (PDPs), electro luminescent displays (ELD), and vacuum fluorescent (VFD) 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, LCD is the most widely used as the substitute for CRT (Cathode Ray Tube) for mobile image display device because of its excellent image quality, light weight, thinness, and low power consumption. In addition to the use of the present invention has been developed in various ways such as a television and a computer monitor for receiving and displaying broadcast signals.

In order to use such a liquid crystal display as a general screen display device in various parts, it is a matter of how high quality images such as high definition, high brightness and large area can be realized while maintaining the characteristics of light weight, thinness and low power consumption. Can be.

The general liquid crystal display device is comprised from the 1st board | substrate and the 2nd board | substrate bonded by the fixed space, and the liquid crystal layer injected between the said 1st board | substrate and the 2nd board | substrate.

In more detail, the first substrate has a plurality of gate lines in one direction and a plurality of data lines at regular intervals in a direction perpendicular to the gate line to define a pixel area. A pixel electrode is formed in each of the pixel regions, and a thin film transistor is formed at a portion where the gate line and the data line cross each other, and the data signal of the data line is applied to each pixel electrode according to a signal applied to the gate line. To apply.

In addition, a black matrix layer is formed on the second substrate to block light in portions other than the pixel region, and R, G, and B color filter layers are formed on portions corresponding to the pixel regions. The common electrode is formed on the color filter layer to implement an image.

In the liquid crystal display as described above, the liquid crystal of the liquid crystal layer formed between the first and second substrates is aligned by an electric field between the pixel electrode and the common electrode, and the light passes through the liquid crystal layer according to the degree of alignment of the liquid crystal layer. You can express the image by adjusting the amount of.

Such a liquid crystal display is called a twisted nematic (TN) mode liquid crystal display, and the TN mode liquid crystal display has a disadvantage of having a narrow viewing angle, and thus an in-plane (IPS: In-Plane) for overcoming the disadvantages of the TN mode. Switching mode liquid crystal display device has been developed.

In the transverse electric field (IPS) mode liquid crystal display, a pixel electrode and a common electrode are formed parallel to each other at a predetermined distance in a pixel area of the first substrate so that a transverse electric field (horizontal electric field) is generated between the pixel electrode and the common electrode. The liquid crystal layer is aligned by the lateral electric field.

Meanwhile, spacers are formed between the first and second substrates of the liquid crystal display device formed as described above to maintain a constant gap between the liquid crystal layers.

Such spacers are divided into ball spacers or column spacers according to their shape.

The ball spacer has a spherical shape, is distributed and manufactured on the first and second substrates, the movement is relatively free even after the bonding of the first and second substrates, and the contact area with the first and second substrates is small.

On the other hand, the column spacer is formed in an array process on the first substrate or the second substrate, and is fixed in a pillar shape having a predetermined height on the predetermined substrate. Therefore, the contact area with the 1st, 2nd board | substrate is relatively large compared with a ball spacer.

Hereinafter, a liquid crystal display having a conventional column spacer will be described with reference to the accompanying drawings.

1 is a cross-sectional view of a liquid crystal display device including a conventional column spacer.

As shown in FIG. 1, a liquid crystal display including a conventional column spacer includes a first substrate 30 and a second substrate 40 facing each other, and a column formed between the first and second substrates 30 and 40. And a liquid crystal layer (not shown) filled between the spacer 20 and the first and second substrates 30 and 40.

On the first substrate 30, the gate lines 31 and the data lines (not shown) are arranged perpendicularly to each other to define pixel regions, and the gate lines 31 and the data lines cross each other. A thin film transistor TFT is formed, and a pixel electrode (not shown) is formed in each pixel area.

The black matrix layer 41 is formed on the second substrate 40 to correspond to an area except the pixel area, and the color filter layer 42 on the stripe corresponding to the pixel areas on the vertical line parallel to the data line is formed. The common electrode or overcoat layer 43 is formed on the front surface.

Here, the column spacer 20 is formed corresponding to a predetermined position on the gate line 31.

In addition, a gate insulating layer 36 is formed on the entire surface of the substrate including the gate line 31 on the first substrate 30, and a passivation layer 37 is formed on the gate insulating layer 36.

2A and 2B are plan and cross-sectional views illustrating a touch failure of a liquid crystal display including a column spacer.

As shown in FIGS. 2A and 2B, when the liquid crystal display device including the above-described conventional column spacer touches the surface of the liquid crystal panel 10 in a predetermined direction using a hand or other object, the touched portion Stain occurs at Such spots are referred to as spot spots generated at the time of touch, and are referred to as touch spots, and are also referred to as touch defects because spots are observed on the screen.

Such a touch failure is considered to be large because the contact area between the column spacer 20 and the first substrate 1 facing the column spacer 20 is larger than the structure of the previous ball spacer. That is, since the column spacer 20 formed in a cylindrical shape compared to the ball spacer has a large contact area with the first substrate 1 as shown in FIG. 2B, the first and second substrates 1 and 2 are touched. After the liver is shifted, it takes a long time to restore to the original state, so the stain remains until the original state is restored.

The conventional liquid crystal display including the column spacer has the following problems.

First, since the contact area between the column spacer and the opposing substrate is large, when the substrate is shifted during the touch due to the large frictional force, it takes a long time to recover to the original state, and touch failure is observed during the restoration time.

Second, when the surface of the liquid crystal panel is pressed during the reliability test or the module process after manufacturing the liquid crystal panel, the column spacer of the portion where the external force is concentrated is crushed, and this phenomenon occurs in black. This is caused by a poor squeezing and at this time, the generated unevenness is referred to as a uneven staining. In a liquid crystal display device including a column spacer, such poor crushing is frequently observed.

The present invention has been made to solve the above problems by forming column spacers on a flat substrate using a mask having a circular slit, to prevent the touch and pressing failure by varying the height of the column spacer for each region There is an object thereof to provide a liquid crystal display device and a method for manufacturing the same.

According to an aspect of the present invention, there is provided a liquid crystal display device including a first substrate on which a thin film transistor array is formed, a second substrate facing the first substrate, and a color filter array flat on the second substrate; A first column spacer formed at a first height h1 at a portion thereof, and a second height h2 spaced apart from the first column spacer on the second substrate and smaller than a height of the first column spacer; It is characterized in that it comprises a column spacer and a liquid crystal layer filled between the first substrate and the second substrate.

The color filter array may include a black matrix layer formed on a predetermined area on the second substrate, a color filter layer formed on a second substrate including the black matrix layer, and an overcoat formed on the entire surface of the second substrate including the black matrix layer and the color filter layer. It comprises a layer.

The color filter layers include a plurality of color films each representing a different color.

The plurality of color films are formed at the same height as each other.

The thin film transistor array includes a gate line and a data line crossing each other to define a pixel region, a thin film transistor formed at an intersection of the gate line and the data line, and a pixel electrode formed in the pixel region.

It further comprises a common electrode on the front of the second substrate.

The pixel region further includes a common electrode having an alternating shape with the pixel electrode.

And a protrusion having a corresponding surface having an area smaller than that of the first column spacer on a portion corresponding to the first column spacer on the first substrate.

The protrusion is formed on the gate line.

The protrusions are formed together in forming the data line.

The second column spacer has a separation distance between the first and second substrates when the second column spacer is bonded to the first substrate.

The separation distance between the second column spacer and the first substrate is 500 to 6000 m 3.

The separation distance between the second column spacer and the first substrate is 3000 to 5000 mm.

The critical dimension of the first column spacer is 6-100 μm.

The first and second column spacers are made of the same mask.

In addition, the manufacturing method of the liquid crystal display device of the present invention for achieving the same object comprises the steps of preparing a first substrate and a second substrate, forming a thin film transistor array on the first substrate, on the second substrate Forming a color filter array, totally applying a photosensitive resin onto a second substrate including the color filter array, and defining a transflective portion including a transmissive portion and a circular slit on a predetermined portion on the photosensitive resin, respectively. Preparing a mask, and patterning the photosensitive resin using the mask, a portion corresponding to the transmissive portion forms a first column spacer having a first height, and a portion corresponding to the transflective portion is the first height Forming a second column spacer having a lower second height, and forming a liquid crystal on either one of the first substrate and the second substrate. It is another feature that comprises the step of dropping and the step of inverting and bonding the remaining substrate, the liquid crystal of the first and second substrate is not dropped.

It includes one to three circular slits in the transflective portion.

The width of the circular slit is 0.5 ~ 6.0㎛.

When the circular slit is a plurality of slits, the distance between the slits and the slits is equal to or larger than the slit width.

The method may further include forming a protrusion on the first substrate.

The protrusions are simultaneously formed when the thin film transistor array is formed.

The photosensitive resin consists of a negative photosensitive material.

In addition, the manufacturing method of the liquid crystal display device of the present invention for achieving the same object comprises the steps of preparing a first substrate and a second substrate, forming a thin film transistor array on the first substrate, on the second substrate Forming a color filter array, totally applying a photosensitive resin onto a second substrate including the color filter array, a semi-transmissive portion including a light shielding portion and a circular slit on a predetermined portion on the photosensitive resin, respectively; Preparing a mask, and patterning the photosensitive resin using the mask, a portion corresponding to the light blocking portion forms a first column spacer having a first height, and a portion corresponding to the transflective portion is formed of the first photoresist. Forming a second column spacer having a second height lower than one height, and forming a liquid crystal on either one of the first substrate and the second substrate. It is another feature that comprises the step of dropping and the step of inverting and bonding the remaining substrate, the liquid crystal of the first and second substrate is not dropped.

The photosensitive resin is made of a positive photosensitive material.

Hereinafter, first, a problem of various structures of a liquid crystal display device having a column spacer will be analyzed and a liquid crystal display device having a structure capable of solving touch defects and deterioration defects will be described.

In the liquid crystal display having the conventional column spacer illustrated in FIG. 1, column spacers are formed in the same shape and the same height for every area of the liquid crystal panel. In this case, since the area where the column spacer and the opposing substrate contact each other is large, the friction force between the column spacer and the opposing substrate becomes large, so that restoration of the original state may take a long time when a user pushes or pushes in one direction, which may cause black luminance non-uniformity. have. On the other hand, the structure of the liquid crystal panel has a large contact area between the column spacer and the opposing substrate for each area of the liquid crystal panel, and thus may be significantly resistant to the pressing by external force.

However, in the liquid crystal display including the conventional column spacer as shown in FIG. 1, efforts have been made to compensate for the black luminance unevenness remaining in the touch when touched, and the proposed structure results in a dual column spacer structure and protrusion. Structure.

3 is a cross-sectional view illustrating a liquid crystal display including a general dual column spacer.

As shown in FIG. 3, a liquid crystal display having a general dual column spacer includes a first substrate 50 on which a thin film transistor array (not shown) and a first substrate 50 are formed, respectively. A second column 60 formed with a filter array, a first column spacer 70 in contact with the first substrate 50 formed corresponding to a region having a high step on the second substrate 60, and the second And a second column spacer 71 formed on the substrate 50 to correspond to a region having a relatively low step, and a liquid crystal layer (not shown) filled between the first and second substrates 50 and 60. . In this case, it is assumed that the first and second column spacers 70 and 71 have the same height.

Meanwhile, the first and second substrates 50 and 60 include a plurality of pixel regions, and are defined by interposing non-pixel regions at portions spaced apart from each pixel region.

The color filter array may include a black matrix layer 61 formed in the non-pixel region on the second substrate 60, a color filter layer 62 formed on the second substrate 60 including the pixel region, And an overcoat layer 63 formed on the entire surface of the second substrate 60 including the black matrix layer 61 and the color filter layer 62.

In this case, the color filter layer 62 is formed with a step for each pixel area. For example, when the color filter layer 62 is formed of R, G, and B color films, the color films of the respective colors are formed to correspond to the pixel regions in a predetermined arrangement, and the color films of the respective colors are different from each other. Application is made in thickness.

As described above, in the general dual column spacer structure, column spacers are disposed by using the thickness difference of the color filter layer 62 for each region, so that some of the column spacers are in contact with the first substrate 50, and the rest of the column spacers are in contact with the first substrate 50. The structure is spaced apart from the first substrate 50. That is, by disposing the first and second column spacers 70 and 71 on the color filter layers 62 having different thicknesses, the first column spacer 70 is in contact with the first substrate 50. The second column spacer 71 is spaced apart from the first substrate 50 and serves as a supporting function together with the first column spacer 70 at the time of the pressing. The crushing phenomenon, i.e., paint stain (pressing stain) was prevented.

However, in such a dual column spacer structure, the upper area of the first column spacer responsible for the cell gap (in this case, assuming a lower surface as a corresponding surface of the first column spacer formed on the second substrate) is maintained. Since it contacts with a 1st board | substrate, contact area does not reduce significantly at the time of actual bonding or touch, and it is difficult to control black luminance nonuniformity.

In addition, the step of each region of the color filter layer 62 may be determined in an application and patterning process, and it is difficult to control the thickness of the color filter layer 62 to be substantially uniform for each region. Therefore, it is difficult to adjust the separation distance H between the second column spacer 71 and the first substrate 50.

Here, the separation distance between the second column spacer 71 and the first substrate is substantially, when an external pressure is applied, the second column spacer together with the first column spacer serves to support the first and second substrates. It is related to whether or not, it is an important factor in determining whether or not poor compression effect.

4 is a cross-sectional view illustrating a liquid crystal display including a dual column spacer including a protrusion structure.

As shown in FIG. 4, in the liquid crystal display having the dual column spacer including the protrusion structure, the protrusion 55 is formed on the first substrate 50 corresponding to the first column spacer 70 in the structure of FIG. 3. It is a structure. This structure has a corresponding surface (upper surface, at this time, the first column spacer corresponding surface formed on the second substrate) of the lower surface relative to the corresponding portion of the first column spacer 70. The first column spacer at the time of bonding or touch by providing a projection 55 formed with a corresponding surface smaller than the upper surface (assuming that the projection corresponding surface formed on the first substrate is a lower surface). The contact area between the 70 and the first substrate 50 may be reduced, and the separation distance H between the second column spacer 71 and the first substrate 50 may be increased. Here, it is assumed that the heights of the first and second column spacers 70 and 71 are the same.

Meanwhile, the separation distance H between the second column spacer 71 and the first substrate 50 is the thickness of the color filter layer 62 at the portion where the first and second column spacers are formed, and the first distance. The thickness aa of the second column spacers 70 and 71 and the thickness h1 of the protrusion 55 may vary. As described above, it is difficult to control the uniform thickness of the color filter layer 62 for each region, and the protrusions 55 formed in the thin film transistor array manufacturing process may also generate tolerances for each region in addition to the required thickness. In practice, it is difficult to adjust the separation distance to a range of desired values. In addition, in the case where the separation distance is set to a very small value around 5000 kPa, it is particularly difficult to control the separation distance H between the second column spacer 71 and the first substrate 50.

In the dual column spacer structure including the protrusion structure, the first column spacer 70 is in contact with the first substrate 50 to maintain a cell gap function, and the second column spacer 71 is formed of the first column spacer 71. The first substrate spacer 70 is spaced apart from the first substrate 50 to serve as a supporting function together with the first column spacer 70 to prevent crushing, that is, coating stain (press stain).

As described above, in the dual column spacer formed on the second substrate 60 having different heights, the main factors in the condition of preventing display defects are H (the second column spacer 71 and the first substrate 50). ), And the luminance non-uniformity caused by pressing and touch has a close relationship with H. If H is smaller, the press is better, but the touch luminance non-uniformity level is worse. If H is large enough, the touch luminance non-uniformity level is good, but it is vulnerable to pressing. Therefore, ensuring a uniform and proper H is of utmost importance.

Hereinafter, the liquid crystal display of the present invention and the manufacturing method thereof having a structure capable of maintaining a uniform H (separation distance between the second column spacer and the first substrate).

5 is a cross-sectional view illustrating a liquid crystal display of the present invention.

5 is a complementary structure of FIG. 4, and includes a first substrate 100 having a thin film transistor array (not shown) and a second substrate 200 facing the first substrate 100 and having a color filter array formed thereon. ), A first column spacer 210 in contact with the first substrate 100 formed to correspond to a region having a high step on the second substrate 200, and a relatively step on the second substrate 200. And a liquid crystal layer 150 filled between the second column spacer 220 and the first and second substrates 100 and 200.

Meanwhile, the first and second substrates 100 and 200 include a plurality of pixel regions, and are defined by interposing non-pixel regions at portions spaced apart from each pixel region.

The color filter array may include a black matrix layer 201 formed in the non-pixel region on the second substrate 200, a color filter layer 202 formed on the second substrate 200 including the pixel region, And an overcoat layer 203 formed on the entire surface of the second substrate 200 including the black matrix layer 201 and the color filter layer 202.

In this case, the upper surface of the color filter layer 202 is formed in each pixel area without a step, and the overcoat layer 203 has a step that may be generated when the color filter layer 202 is formed. Compensation is made to form the top surface flat, so that the first and second column spacers 210 and 220 are formed on a uniform surface.

Here, when the color filter layer 202 is formed of R, G, and B color films, color films of different colors correspond to the plurality of pixel areas formed at equal intervals. At this time, each of the color film is formed at the same height, even if the color film is not formed to the same height due to an error during the process, it is to flatten the surface by using the overcoat layer 203 .

Here, the first column spacer 210 is in contact with the first substrate 100 at the time of bonding to serve a cell gap retention function, and the second column spacer 220 is the first substrate 100 at the time of bonding. ) Is spaced apart from the predetermined interval H, and when the pressing occurs due to an external pressure, the first column spacer is contacted with the first column spacer 210 together with the first column spacer 210. It is possible to prevent the change in the shape of the column spacers by distributing the pressure received. The bonding distance H between the second column spacer 220 and the first substrate 100 is 500 mW to 6000 mW when the liquid crystal display device is formed in the present invention, and is preferable for improving touch failure and crushing unevenness. The distance is 3000 ~ 5000Å.

In such a structure, since the first and second column spacers 210 and 220 are formed on the flat second substrate 200, the second column spacer 220 and the first substrate 100 may be separated from each other. The separation distance is controlled by varying the thickness formed during the formation of the first and second column spacers 210 and 220.

6 is a cross-sectional view of a liquid crystal display according to another exemplary embodiment of the present invention.

FIG. 6 further illustrates a protrusion 110 formed on the first substrate 100 corresponding to the first column spacer 210 in the structure of FIG. 5. The protrusion 110 contacts the first column spacer 210 during bonding and touch. By making the portion on the first substrate 100 to be the upper surface of the protrusion 100, contact with the column spacers and the first substrate 100 in a small area, it is easy to restore to the original state when touched The black luminance nonuniformity can be prevented more effectively.

In the structure (FIGS. 5 and 6) of the liquid crystal display of the present invention described above, the first and second column spacers are formed at different heights in the manufacturing process of the column spacers. At this time, when forming the first and second column spacers, a photosensitive resin is used, and the exposure is performed by changing the shape of each region (corresponding to the first and second column spacers) of the mask corresponding to the upper portion of the photosensitive resin. And develop at different heights.

In this case, the shapes of the masks forming the first column spacer and the second column spacer are as follows.

7A and 7B are plan views illustrating masks for forming the first column spacer and the second column spacer of the liquid crystal display of the present invention.

The mask 300 for forming the first and second column spacers 210 and 220 is the same mask, and one mask may correspond to a portion of the first column spacer 210 formed therein, as shown in FIG. 7A. ), And corresponding to the portion of the second column spacer 220 formed as a region of the semi-transmissive portion 307, as shown in Figure 7b. In this case, as shown in FIG. 7A, the shape of the transmissive part 305 is formed according to the shape of the horizontal cross section of the first column spacer 210 to be formed. As shown in FIG. 7B, the shape of the transflective part 307 has a predetermined width. and a circular slit 302 having (d). Here, when the width of the circular slit 302 is d, the transflective portion 307 is defined by the outline of the circular slit. The radius of the inner circle of the circular slit 302 is r1, and the radius of the outer circle corresponds to r2. In this case, the critical dimension of the semi-transmissive portion 307 will correspond to 2 * r2.

The material for forming the first and second column spacers 210 and 220 in correspondence with the mask 300 shown in FIG. 1 is a negative photosensitive resin of the photosensitive resin. The non-removed site is removed.

If the material forming the first and second column spacers 210 and 220 is a positive photosensitive resin, the openings and the light blocking portions of the mask 300 may be reversed. That is, the transparent part 305 of the mask 300 is formed as the light blocking part, the light blocking part 301 will be defined as the opening, and the circular slit 302 in the transflective part 307 is exposed to the positive photosensitive resin. In view of the nature of the part being removed, it may be formed by subtracting the width and the interval between the circular slit 302.

8A to 8D are plan views illustrating masks for forming the second column spacer of the present invention.

The semi-transmissive portion of the mask for forming the second column spacer of the present invention may be formed having a circular slit 302a of the first width, as shown in FIG. 8A, and wider than the first width, as shown in FIG. 8B. It may be formed to have a circular slit 302b, and as shown in Fig. 8c, a square light shielding portion 301 is entered again into the circular transmission portion, arc-shaped slits 302c except for the light shielding portion 301 is provided As shown in FIG. 8D, a square light shielding portion 301 is entered into the circular transmission portion again, a circular transmission portion is provided in the light shielding portion 301, and a square light shielding portion is provided in the circular transmission portion. 301 is provided, it is made into a structure in which a circle and a square of a smaller size are alternately formed. In this case, a circle is defined as a transmissive portion, and a square is defined as a light shielding portion. Here, the first and second slits 302d and 302e, which are hidden by the light blocking portions 301, have an arc shape.

Here, the factors directly related to the shape of the second column spacer 220 are the number of circular slits 302 in the transflective portion, the width and the degree of separation of the circular slits 302. In this case, the number of said circular slits 302 shall be at least 1, Preferably it is a plurality. In addition, the width of the circular slit 302 may be larger than 0.5 μm, preferably about 0.5 to 6.0 μm. Experimentally, the width d of the circular slit was 2 μm, thereby forming a second column spacer 220 having an appropriate separation distance H from the first substrate 100. A distance between the second column spacer 220 and the first substrate 100 formed when the width of the circular slit was 2 μm corresponded to 3000 to 5000 μs. The degree of separation between the circular slits 302 is at least equal to or greater than the width d of the circular slits 302.

On the other hand, the number of the circular slits 302 is preferably 1 to 3, but this is the case that the critical dimension of the transflective portion is about 18㎛, and when the threshold dimension of the semi-permeable portion is more than that the number of circular slits 302 is It can grow further. In the liquid crystal display of the present invention, the critical dimension (CD) of the lower surfaces (the formation surfaces of the second substrate) of the first and second column spacers 210 and 220 is set to 6 to 100 μm. It was advantageous for the formation of the second column spacer 220 having a height difference from the first column spacer 210 so that the ratio of the opening by the slit 302 was 50% or less compared to the entire transflective portion.

In addition, as shown in FIGS. 8C and 8D, when the portion of the mask 300 forming the second column spacer 220 has a shape in which a circular transmissive portion and a rectangular shading portion alternate, the width of the slit is designed. It was difficult to form uniformly, and even if the opening ratio of the whole semi-transmissive part at the time of design was about 50%, it was observed that formation of a 2nd column spacer was difficult.

However, in the future, if the circular slits of the mask can be implemented more finely, the shape of the slits of the mask is not limited to the circular slits, but may be in the form of alternating the circular transmission portion and the rectangular shading portion, or in the shape of a rhombic slit. I will say. In the case of the lozenge, since the exposure area is reduced, the shape of the column spacer formed after the exposure will correspond to the lozenge entering the inside.

Hereinafter, the formation profile of the second column spacer according to the shape of the transflective portion will be described.

9A and 9B are plan views showing masks for forming a first column spacer and a second column spacer having a single circular slit in the liquid crystal display of the present invention, and a profile showing a second column spacer formed using the same. to be.

As shown in FIG. 9A, the semi-transmissive portion 307 of the mask 300 for forming the second column spacer 220 has a shape having one circular slit 302 of interval d in the semi-transmissive portion of the radius r ₂ , and the first The transmission portion 305 of the mask 300 for forming the column spacer 210 has an r ₃ radius.

When the photosensitive resin is exposed and developed by using such a mask and patterned, as shown in FIG. 9B, a portion corresponding to the transflective portion has a second column spacer having a sharp upper surface. That is, the second column spacer is patterned in a form having an acid shape.

10A and 10B illustrate a plan view of a mask for forming a first column spacer and a second column spacer, including a plurality of circular slits, and a second column spacer formed using the liquid crystal display of the present invention. Profile shown.

As shown in FIG. 10A, the semi-transmissive portion 317 spaces the circular slits 312 (312a, 312b, 312c) with the interval d equally spaced from each other, and has the same interval (width) d, half in the radius of r ₂ If three are provided in the permeation part 317 and the permeation part 305 is formed as a circular opening, the first column spacer will be formed in the same shape as in the mask of FIG. 9A to have a first height, and the second column spacer will be As shown in Figure 10b, the upper surface will be formed in a flat shape.

Here, the transflective portion 317 is formed such that the circular slits 312a, 312b, and 312c having concentric circles within a radius r ₂ have a smaller radius toward the inside thereof, and the regions except for the circular slits 312a, 312b, and 312c are different from each other. It is defined as the miner 301.

As such, when the transflective portion has more circular slits, the upper surface of the second column spacer is formed to be flatter. When the transflective portion is formed to be flat, the pressure at the time of pressing is more than that of the case. The contact area is increased, so the anti-pressing function is good.

Round Slit Count Exposure amount mJ / ㎠ LCD margin Press-resistant 1 (Fig. 9a) 250 3.83 dots (4.2%) 4Kgf feeble 300 4.33 dots (4.8%) 4Kgf feeble 3 (Fig. 10a) 250 4.33 dots (4.9%) 7Kgf about 300 5.00 dots (5.5%) 7Kgf feeble

As shown in Table 1, the exposure doses were 250 mJ / cm 2, respectively, corresponding to the mask of FIG. 9A and the mask of FIG. 10A, respectively. , 300mJ / cm 2 shows the liquid crystal margin and the pressing resistance of the liquid crystal panel including the first and second column spacers.

In the case of dropping 88 to 90 dots on the liquid crystal panel, when one circular slit is provided, the liquid crystal panel at the time of forming the first and second column spacers has an exposure amount of 250 mJ / cm 2 , respectively. The liquid crystal margin that can be resolved was about 3.83 dots, representing about 4.2% of the total amount of liquid crystal dots. In this case, the resistance to the pressing pressure was weak at 4 Kgf. That is, it was weak for the pressing pressure of 4Kgf or more, and it was determined that the pressing resistance was relatively weak. When the exposure amount is 300 mJ / cm 2, respectively, using the same mask (with one circular slit), the liquid crystal margin is increased to about 0.5 dot to 4.33 dots. In this case, the resistance to the pressing pressure is 4 Kgf, which is the same as the exposure dose of 250 mJ / cm 2, and it can be seen that the coating stain is almost independent of the exposure dose.

When three circular slits of a mask for forming the second column spacer were provided under the same liquid crystal dropping amount, when the exposure amount was 250 mJ / cm 2, the liquid crystal margin was 4.33 dots, the coating stain was about 7 Kgf, and the exposure amount was 300 mJ. In the case of / cm 2, the liquid crystal margin is 5.00 dots, and the coating stain is 7 Kgf. The liquid crystal margin tends to increase when the exposure dose is increased, and the coating stain tends to be improved when the number of circular slits increases.

On the other hand, the pressure at the time described above may be carried out in a separate pressing test before the release of the liquid crystal display, or may be made in an assembly process of assembling the liquid crystal display module.

Hereinafter, a detailed plan view of the liquid crystal display of the present invention will be described with reference to the accompanying drawings.

11 is a plan view illustrating a liquid crystal display of the present invention.

As shown in FIG. 11, the liquid crystal display of the present invention is largely divided into a first substrate (see 100 of FIGS. 5 and 6) and a second substrate (see 200 of FIGS. 5 and 6) facing each other, and the first, And a liquid crystal layer (see 150 of FIGS. 5 and 6) filled between the second substrates 100 and 200.

On the first substrate 100, a thin film transistor TFT formed at an intersection of the gate line 101 and the data line 102 and the gate line 101 and the data line 102 that cross each other to define a pixel area. ), A first storage electrode 103a electrically connected to the drain electrode 102b of the thin film transistor TFT, a pixel electrode 103 branched from the first storage electrode 103a, and the pixel electrode. A branched common electrode 104 alternated with 103 and a common line 104a and the common line 104a and the common electrode 104 formed in the pixel area in parallel with the gate line 101 in parallel with each other. And a second storage electrode 104b connected to the first storage electrode 103a and overlapping the first storage electrode 103a.

In this case, the thin film transistor TFT is defined in a region between a source electrode 102a and a drain electrode 102b having a 'U' shape, and the channel is formed along the inside of the shape of the source electrode 102a. It is defined as U '. The thin film transistor TFT may include a gate electrode 101a protruding from the gate line 101, a 'U' source electrode 102a protruding from the data line 102, and the 'U'. The drain electrode 102b is formed to be spaced apart from the female source electrode 102a by a predetermined interval and enters into the 'U'-shaped source electrode 102a. A semiconductor layer (not shown) is further formed below the data line 102, the source electrode 102a, the drain electrode 102b, and the channel region between the source electrode 102a and the drain electrode 102b. . Here, the semiconductor layer is formed of a laminate of an amorphous silicon layer (not shown) and an n + layer (impurity layer) (not shown) from below, and corresponds to a region between the source electrode 102a and the drain electrode 102b. In the channel region, the n + layer (impurity layer) is removed. The semiconductor layer may be selectively formed only under the source / drain electrodes 102a and 102b and the region therebetween, or the data line 102, the source electrode 102a and the region except for the channel region. It may be formed under the drain electrode 102b. Meanwhile, as illustrated, the shape of the source electrode 102a is 'U', and the liquid crystal display having the 'U' channel has been described. However, the liquid crystal display of the present invention is the source electrode 102a. May be formed to protrude from the data line 102 in a '-' shape, or may be formed in other shapes.

Here, the gate line 101, the common line 104a, and the common electrode 104 are formed of the same metal on the same layer.

A gate insulating film (not shown) is interposed between the gate line 101 and the semiconductor layer, and a protective film (not shown) is interposed between the data line 102 and the pixel electrode 103. do.

Meanwhile, the second storage electrode 104b connected to the common line 104a passing through the pixel region, the first storage electrode 103a formed thereon, and the gate insulating layer 105 and the passivation layer interposed between the two electrodes. 106 constitutes a storage capacitor.

Here, the drain electrode 102b and the first storage electrode 103a formed between the different layers may be contact holes 106a formed by removing the passivation layer 106 on an upper portion of the drain electrode 102b. Contact via).

On the other hand, as shown in Figure 6, when the projection 110 is formed on the first substrate 100, a semiconductor layer pattern (not shown) and the source / of the same layer as the semiconductor layer (not shown) A stack of the drain electrodes 102a and 102b and a metal layer pattern (not shown) on the same layer is formed on the gate line 101, the common line 104a, or the second storage electrode 104b. Here, the thickness of the semiconductor layer pattern is about 0.2 ~ 0.3㎛, the thickness of the metal layer pattern is about 0.2 ~ 0.4㎛, the projection (110) is not compared to the portion on the remaining gate line 101, the projection ( In the portion where 110) is formed, a step is formed about 0.4 to 0.7 m. When the protrusion 110 is formed, the height of the second column spacer 220 is higher than that of FIG. 5, so that the distance between the second column spacer 220 and the first substrate 100 is desired. Can be leveled

The liquid crystal display including the protrusions 110 may include a first column spacer formed on the protrusions 110 and the second substrate 200 when the first and second substrates 100 and 200 are bonded to each other to form a cell gap. 210 corresponds. At this time, the upper surface of the protrusion 110 is relatively the upper surface of the first column spacer 210 (in this case, the first column spacer 210 formed on the second substrate 200) 2, the surface corresponding to the substrate 200 is assumed to be a lower surface, and at this time, the first column spacer 210 and the protrusion 110 are contacted with each other by the upper surface of the protrusion 110. 1 The column spacer 210 and the protrusion 110 are in contact with each other.

Here, a passivation layer 106 formed in the remaining region except for the contact hole 106a is further disposed on the protrusion 110 to contact the first column spacer 210 formed on the second substrate 200. The portion to be corresponds to the protective layer 106 on the protrusion 110.

On the other hand, on the second substrate 200 facing the first substrate 100, a black matrix layer 201 formed corresponding to a region (gate line and data line region) except for the pixel region, and the second substrate An overcoat layer 203 for planarization is formed on the color filter layer 202 formed on the 200 and the second substrate 200 including the black matrix layer and the color filter layer.

The first column spacer 210 and the second column spacer 220 are formed on the gate line 101, the common line 104a, or the second storage electrode 104b, and the first column spacer 210. ) Is in contact with the first substrate 100, and the second column spacer 220 is relatively spaced apart from the first substrate 100 compared to the second column spacer 220. ) Is formed high.

In this case, only the first column spacer 210 may be in contact with the first substrate 100 during bonding and pushing or sweeping the surface of the first substrate 100 or the second substrate 200. Since the contact area is small and thus the frictional force is small, restoring to the original state after the touch is easy, and it is possible to prevent the black brightness unevenness due to the touch.

In addition, the first column spacer 210 is in contact with the first substrate 100 during a pressing test by applying a predetermined pressure or more, and as the pressure increases, the second column spacer 220 becomes the first substrate. In addition to contacting the corresponding site on the 100, the contact site can be increased to disperse the pressure at the time of pressing.

Meanwhile, the first and second column spacers 210 and 220 may be formed in various shapes such as a polygonal shape such as a circular cross section or a square. In consideration of the alignment margin in the process, it may be advantageous to form a circular or regular polygon.

Hereinafter, a method of forming column spacers having different heights of the liquid crystal display of the present invention will be described.

12A to 12C are cross-sectional views illustrating a process of forming column spacers of the liquid crystal display of the present invention.

As shown in FIG. 12A, first, a color filter array is formed on the second substrate 200. The color filter array represents a black matrix layer, a color filter layer, and an overcoat layer, and is formed as follows. That is, the black matrix layer 201 is formed on the second substrate 200 except for the pixel region, and the color filter layer 202 is formed on the second substrate 200 including the black matrix layer 201. The front overcoat layer 203 is formed on the second substrate 200 including the black matrix layer 201 and the color filter layer 202.

First, as shown in FIG. 12B, a front surface photosensitive resin is formed on the entire surface of the second substrate 200 including the overcoat layer 203.

As shown in FIG. 12C, the permeation part is defined at a portion corresponding to the first column spacer, and the mask 300 in which the transflective portion 307 is defined is aligned at the portion corresponding to the second column spacer. Here, the transmission part 305 of the mask 300 has a shape corresponding to the shape of the horizontal cross section of the first column spacer 210 to be formed, for example, the first column spacer 210 to be formed. Similarly, when the horizontal cross section is circular, the permeation part 305 is also formed in a circular shape, and when the horizontal cross section of the first column spacer 210 is a rectangular shape, the permeation part 305 is also formed in a rectangle.

In this case, the photosensitive resin 204 is a material having negative photosensitivity, and a portion receiving light is left by internal crosslinking during development after exposure, and a portion not receiving light is removed. In this case, the more the circular slit 302 provided inside the photosensitive resin 204, the larger the exposure amount is at the corresponding part. The smaller the circular slit 302 is, the lower the exposure amount and the greater the amount of light blocking. It remains smaller than the applied photosensitive resin. Here, when the interval between the circular slits 302 is small, a diffraction exposure effect due to interference of light occurs. Due to this diffraction effect, only a portion corresponding to the opening of the circular slit remains and a portion corresponding to the remaining light shielding portion is Rather than removing the patterning, the semi-permeable portion of the photosensitive resin having the slits is partially removed with a uniform thickness, so that the thickness C ₂ is relatively lower than that of the first column spacer 210. The second column spacer 220 of (C ₁ ) is formed.

On the other hand, the semi-transmissive portion is provided with the circular slit 302, thereby providing not only a low elasticity (having an elastic recovery rate of about 67% or less) but also a high elastic photosensitive resin (elastic recovery rate of about 70% or more), in which high sensitivity patterning is possible. Has a flat surface at the time of exposure and development compared to other shapes, and enables uniform patterning for each region.

As described above, the photosensitive resin 204 may be formed of a positive photosensitive resin. In this case, the photosensitive resin 204 may be formed as a light blocking portion corresponding to a forming portion of the first column spacer 210, and the light blocking portion and the transflective portion may be formed. A mask 300 is prepared in which remaining regions except the openings are defined as openings.

After preparing the second substrate 200 having the first and second column spacers 210 and 220 having different heights, and the first substrate 9100 on which the thin film transistor array shown in FIG. 11 is formed, After dropping a liquid crystal (not shown) on the first substrate 100 or the second substrate 200 and inverting the substrate 100 or 200 on which the liquid crystal is not dropped, the first and second substrates 100 , 200) are bonded together to form a liquid crystal panel.

The embodiments described above have been described with respect to the in-plane switching (IPS) mode, and may be applicable to the twisted nematic (TN) mode. In the case of the twisted nematic mode, the pixel electrodes are formed in one pattern on the pixel area of the first substrate, and the common electric field is formed on the front surface of the second substrate. Is formed. In the twisted nematic mode, since the common line is not formed inside the pixel region, the first and second column spacers and the protrusions are all formed on the gate line.

The liquid crystal display of the present invention as described above and a method of manufacturing the same have the following effects.

First, the formation of the first column spacer for maintaining the cell gap and the formation of the second column spacer for preventing the pressing are divided by regions using the same mask, and the photosensitive resin is patterned by changing the shape of the mask for each region. By forming the first and second column spacers, the contact area of the opposing substrate of the column spacers is reduced during touch to prevent black luminance non-uniformity, and when pressed, the second column spacers are in contact with the first substrate after applying a predetermined pressure or more. Dispersion can be prevented to prevent paint stains.

Second, column spacers having different heights may be formed in the same patterning process using the same mask. In this case, second column spacers for preventing squeezing may be provided by providing circular slits to form second column spacers having a low height. The distance between the first substrate and the first substrate depends only on the formation height of the second column spacer, and no other variable is involved in the process, so that the distance between the second column spacer and the first substrate can be easily adjusted. In addition, it is possible to form a second column spacer having a uniform separation distance with little difference in separation distance for each region.

Third, the circular slits of the mask for forming the second column spacer used in the method of manufacturing the liquid crystal display device of the present invention have a distance of about 2 μm and are spaced at equal intervals in a semi-transmissive part having a diameter of about 6 to 100 μm. It has been demonstrated experimentally that the formation of one to three circular slits is effective in forming a second column spacer of uniform height on its surface. In addition, the shape of such a mask can be effectively patterned to the photoelastic resin of high elasticity (material whose elastic recovery rate is 70% or more) in addition to the low elastic photosensitive resin currently developed.

Claims (24)

A first substrate on which a thin film transistor array is formed; A second substrate facing the first substrate and having a flat color filter array; A first column spacer formed at a first height h1 at a predetermined portion on the second substrate; A second column spacer spaced apart from the first column spacer on the second substrate, the second column spacer having a second height h2 smaller than the height of the first column spacer; And And a liquid crystal layer filled between the first substrate and the second substrate. The method of claim 1, The color filter array A black matrix layer formed on a predetermined region on the second substrate; A color filter layer formed on a second substrate including the black matrix layer; And And an overcoat layer formed on the entire surface of the second substrate including the black matrix layer and the color filter layer. The method of claim 2, And the color filter layers comprise a plurality of color films each representing a different color. The method of claim 3, wherein And the plurality of color films are formed at the same height as each other. The method of claim 1, The thin film transistor array A gate line and a data line crossing each other to define a pixel area; A thin film transistor formed at an intersection of the gate line and the data line; And And a pixel electrode formed in the pixel area. The method of claim 5, And a common electrode on the entire surface of the second substrate. The method of claim 5, The pixel area further comprises a common electrode having an alternating shape with the pixel electrode. The method of claim 1, And a projection having a corresponding surface of an area smaller than a corresponding surface of the first column spacer on a portion corresponding to the first column spacer on the first substrate. The method of claim 8, And the protrusion is formed on the gate line. The method of claim 8, And the protrusions are formed together when the data line is formed. The method of claim 1, The second column spacer has a separation distance between the first substrate and the first substrate when the second substrate is bonded to each other. The method of claim 11, And the separation distance between the second column spacer and the first substrate is 500 to 6000 micrometers. The method of claim 12, And the separation distance between the second column spacer and the first substrate is 3000 to 5000 Å. The method of claim 1, The critical dimension of the first column spacer and the second column spacer is 6 ~ 100㎛ characterized in that the liquid crystal display. The method of claim 1, And the first and second column spacers are made of the same mask. Preparing a first substrate and a second substrate; Forming a thin film transistor array on the first substrate and forming a color filter array on the second substrate; Front coating the photosensitive resin on a second substrate including the color filter array; Preparing a mask having a transflective portion including a transmissive portion and a circular slit in a predetermined portion on the photosensitive resin, respectively; The photosensitive resin is patterned using the mask, and a portion corresponding to the transmissive portion forms a first column spacer having a first height, and a portion corresponding to the transflective portion is formed of a second height lower than the first height. Forming a two column spacer; Dropping liquid crystal onto any one of the first substrate and the second substrate; And And inverting and bonding the remaining substrates on which the liquid crystal is not dropped among the first and second substrates. The method of claim 16, And one to three circular slits in the transflective portion. The method of claim 16, The width of the circular slit is a liquid crystal display, characterized in that 0.5 ~ 6.0㎛. The method of claim 18, When the circular slits are a plurality of slits, a distance between the slits and the slits is equal to or larger than the width of the slits. The method of claim 16, Forming a projection on the first substrate further comprising the manufacturing method of the liquid crystal display device. The method of claim 20, And the protrusions are simultaneously formed when the thin film transistor array is formed. The method of claim 16, And the photosensitive resin is made of a negative photosensitive material. Preparing a first substrate and a second substrate; Forming a thin film transistor array on the first substrate and forming a color filter array on the second substrate; Front coating the photosensitive resin on a second substrate including the color filter array; Preparing a mask having a transflective portion including a light shielding portion and a circular slit at a predetermined portion on the photosensitive resin; By using the mask to pattern the photosensitive resin, a portion corresponding to the light blocking portion forms a first column spacer having a first height, and a portion corresponding to the transflective portion has a second height lower than the first height. Forming a second column spacer; Dropping liquid crystal onto any one of the first substrate and the second substrate; And And inverting and bonding the remaining substrates on which the liquid crystal is not dropped among the first and second substrates. The method of claim 23, wherein And the photosensitive resin is made of a positive photosensitive material.

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