JP2003186020A - Liquid crystal display device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device which is manufactured by cutting parts corresponding to respective liquid crystal display devices after sticking together a couple of large-sized original substrates and in which the strain and the display defects of the substrates attributed to the sticking and cutting processes are prevented and also short-circuiting between connection pads is sufficiently prevented, and to provide a manufacturing method for the same. <P>SOLUTION: Dam-shaped projections 11 are provided along a scribe line 16 for cutting the couple of original substrates by scribing and also provided with cut parts 12 and step parts 13 on both edges along a row of connection pads 15. The cut parts 12 are provided for every interval 19 between the connection pads 15 so as to be located at positions nearly corresponding to the intervals and to have a size nearly equal to the interval. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a method for manufacturing the same. In particular, the present invention relates to a method for manufacturing a liquid crystal display device including a step of cutting out a portion corresponding to each liquid crystal display device after bonding a pair of large-sized original substrates via a spacer and a sealing material.

[0002]

2. Description of the Related Art In recent years, flat panel display devices have been actively developed as display devices to replace CRT displays. Among them, liquid crystal display devices have been attracting attention because of their advantages such as light weight, thin thickness and low power consumption. . In particular, an active matrix type liquid crystal display device in which a switch element is electrically connected to each pixel electrode can realize a good display image without crosstalk between adjacent pixels, and is therefore the mainstream of liquid crystal display devices. There is.

A light transmissive active matrix type liquid crystal display device using a TFT (Thin Film Transistor) as a switch element will be described below as an example.

The active matrix type liquid crystal display device is
A liquid crystal layer is held between the array substrate and the counter substrate via an alignment film. In the array substrate, a plurality of signal lines and a plurality of scanning lines are arranged in a grid pattern on a transparent insulating substrate such as glass or quartz via an insulating film, and the signal lines and the scanning lines are arranged in regions corresponding to each grid cell. Pixel electrodes made of a transparent conductive material such as ITO (Indium-Tin-Oxide) are arranged. And
A TFT as a switching element for controlling each pixel electrode is arranged at each intersection of the grid. The gate electrode of the TFT is electrically connected to the scanning line, the drain electrode is electrically connected to the signal line, and the source electrode is electrically connected to the pixel electrode.

The counter substrate is formed by arranging a counter electrode made of ITO on a transparent insulating substrate such as glass, and arranging a color filter layer if color display is realized.

At the outer periphery of the liquid crystal display device, the array substrate projects from the counter substrate to form a shelf-shaped connection region,
The connection pads arranged in this connection region are connected to terminals for input from the external drive system. Further, a sealing material is arranged between the edge portion of the counter substrate and the array substrate to seal the four circumferences of the liquid crystal layer.

In the arrangement region of the liquid crystal layer, a large number of spacers for making the thickness of the liquid crystal layer uniform are arranged. As the spacer, a non-fixed spherical type dispersed on any substrate was used, but recently, a columnar spacer formed by film formation and patterning on any substrate,
A spherical type in which the position is fixed by fusion after spraying is also used.

In manufacturing a liquid crystal display device, "multi-chambering" is performed for the purpose of improving manufacturing efficiency and reducing manufacturing cost.
Is being done. This is, for example, 650 x 550 mm
If you can take 6 (2 x 3) array substrates and counter substrates with a diagonal dimension of 12.1 inches from the large glass substrate of
Various film forming and patterning processes for manufacturing an array substrate or a counter substrate are performed with the dimensions of 650 × 550 mm as it is, and a portion corresponding to each liquid crystal display device is cut out later.

Particularly, first of all, such a large format (for example, 6
50 × 550 mm) array original substrate and counter original substrate,
A large-sized composite cell structure is formed by laminating the image display areas with a sealing material provided therebetween. Then, after that, a cell structure corresponding to each liquid crystal display device is cut out by scribing or the like. The scribe is a process in which a scribe line (writing line) is put on the surface of a glass substrate with a diamond tip or the like, and then a bending force is applied along the scribe line to break the scribe line.

In each image display area, a spacer is arranged in advance to make the thickness of the liquid crystal layer constant, but it corresponds to a peripheral area outside the sealing material, in particular, a shelf-like connection area. In the area, a support structure such as a spacer is not originally arranged. If a pressing force is applied in these areas without a supporting structure, the gap between the substrates becomes smaller,
This causes distortion in the substrate. Therefore, even in the image display region, the space between the substrates becomes non-uniform at a position close to the sealing material, which causes a display defect due to the non-uniform thickness of the liquid crystal layer.

Therefore, in Japanese Patent Application No. 10-193304, columnar spacers similar to those in the image display area are provided in the peripheral area outside the sealing material, and a dummy sealing material is provided along the scribe cut point. Proposed.

[0012]

However, it is difficult to dispose the columnar spacer and the dummy seal material in the region where the connection pads are arranged to form the shelf-shaped connection region. In particular, in order to keep the effective utilization rate of the original substrate sufficiently high and to keep the external dimensions of the liquid crystal display device sufficiently small,
A sufficient margin cannot be provided outside the connection pad.

Therefore, it has been considered to form dam-like projections which are continuous along the scribe cutting line at the same time when the structures in the pixel region such as columnar spacers are formed.

However, the inventor of the present invention diligently studied a short circuit between adjacent connection pads, and in particular, also examined the case where such a support structure was provided. As a result, the connection resulting from the provision of the dam-like projections was found. We have found that short circuits between pads can occur.

The present invention has been made in view of the above problems, and not only can prevent the distortion and display failure of the substrate due to the steps of bonding and cutting the substrate, but also the connection pad and the connection pad. Provided is a liquid crystal display device capable of sufficiently preventing a short circuit between terminals and a manufacturing method thereof.

[0016]

According to another aspect of the present invention, there is provided a liquid crystal display device having a first structure in which a liquid crystal display device is pasted through a spacer and a sealing material.
And a second substrate and a liquid crystal layer held between them,
In a liquid crystal display device including a connection pad arranged on a connection peripheral portion of the first substrate, a dam-like projection is provided on an end edge of a pattern formation surface of the first substrate, and the dam-like projection is used for the connection. In the region along the row of pads, the gaps between adjacent connection pads are omitted.

With the above structure, it is possible not only to prevent the distortion of the substrate and the display failure due to the steps of attaching and cutting the substrate, but also to sufficiently prevent the short circuit between the connection pads.

A liquid crystal display device according to a third aspect of the present invention is a liquid crystal display device of the same premise, wherein a dam-like projection is provided on an edge of the pattern formation surface of the first substrate, and the dam is formed in a region along the row of the connection pads. In addition, step portions are provided on both edges of the dam-like projection.

Even with such a structure, not only the distortion of the substrate and the display failure due to the process of bonding and cutting the substrate but also the short circuit between the connection pads can be sufficiently prevented. it can.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, which comprises: a resin film forming step of forming a resin film pattern having a dam-like projection and having a thickness of 1 μm or more on the first substrate; A step of forming a conductive layer pattern including a pattern and a row of connection pads; a step of attaching the first substrate and a second substrate via a sealant; and a step of attaching the first substrate and the second substrate to each other. In a state of being cut, the substrate cutting step of cutting the first substrate and the second substrate along the dam-like protrusions, and the terminal group of the flexible wiring substrate is electrically connected to the row of the connection pads through conductive adhesive means. And a step of electrically connecting the liquid crystal display device, wherein the dam-like protrusions are omitted for each gap between the adjacent connection pads in a region along the row of the connection pads. It is characterized by being

A method of manufacturing a liquid crystal display device according to a fifth aspect is the same method of manufacturing a liquid crystal display device, wherein, in the resin film forming step, the integrated intensity of exposure of an exposed region is determined by both of the dam-like projections. A step or an inclination is provided at the edge portion, whereby step portions are provided at both edge portions of the dam-like projection, or the inclination angle of the end faces of the both edge portions is reduced, and at the same time, the pixel electrode is formed. It is characterized in that an uneven pattern is formed in the arrangement region.

[0022]

DETAILED DESCRIPTION OF THE INVENTION A liquid crystal display device and a method of manufacturing the same according to a first embodiment will be described with reference to FIGS.

FIG. 1 is a schematic partial cross-sectional perspective view of an edge portion of the display panel body 10 for explaining the main part of the liquid crystal display device of the first embodiment. Moreover, FIG.
FIG. 4 is a diagram for explaining a main part of the manufacturing method. FIG. 2 is a plan view showing a large-sized bonded substrate obtained by bonding an original array substrate and an opposite original substrate before cutting out, and FIG. 3 is a schematic laminated sectional view of the large-sized bonded substrate. Is.

FIG. 1 shows an edge portion of the shelf-like connection area in the display panel body 10.

When cutting out each display panel body 10 from the large-sized bonded substrate 300, if cutting is performed on the entire circumference of the display panel body 10, each cut-out display panel body 10 is formed on the entire array substrate 101. It has dam-like projections 11 along the circumference. This is because, as will be described later with reference to FIG. 3, the dam-shaped projection 11 is provided along the scribe line 16 corresponding to the outer shape of each display panel body 10. As will be described later with reference to FIG. 4, the dam-shaped projections are formed in the process of manufacturing the array original substrate 100.
Thick resin film 150 made of resin similar to resist resin
Consists of.

As shown in FIG. 1, at a location along the row of the connection pads 15, the dam-like projection 11 is provided with a cutout 12 and a step (shoulder) 13. The cutouts 12 are formed at a position and a dimension D such that, for each interval 19 between the adjacent connection pads 15, this interval 19 is translated in parallel toward the edge 101a of the array substrate.

The stepped portion (shoulder portion) 13 can be provided along the entire shelf-shaped connection region 21 where the array substrate 101 projects from the counter substrate, or along the entire edge of the array substrate 101. Although it can be provided, it is arranged at least at a position along the row of the connection pads 15. Step 13
Is created in the step of forming the resin film 150, as described later.

The row of connection pads 15 is, for example, ACF.
It is connected to the output terminal group of TCP via (anisotropic conductive film). As will be described later ((6) Sixth patterning), in the liquid crystal display device of the first embodiment, the presence of the recess 12 and the step 13 prevents the metal layer from remaining along the inner edge of the dam-like projection 11. Therefore, a short circuit between terminals due to the residual metal layer is prevented.

FIG. 2 is a plan view of a large-sized bonded substrate 300 for explaining the manner of multi-layering.
In the large-sized bonded substrate 300, as shown in FIG. 3, the array original substrate 100 before being cut out and the counter original substrate 300 correspond to the respective areas 10-1, 1 corresponding to the display panel body 10.
0-2, 10-3, ... Are attached via a pattern of a rectangular seal material 400.

Each area 10 corresponding to the display panel body 10
-1, 10-2, 10-3, ... First, the array substrate 1
Along the scribe line 16 along the outline of 01, two sheets are scribed and cut out. And
Only the opposing original substrate 200 is cut along the scribe line 17 corresponding to the inner edge of the connection region 21 on the array substrate 101. This is to remove an unnecessary portion of the counter original substrate 200 at a portion covering the connection region 21.

As shown in FIG. 3, the large-sized bonded substrate 300 is provided with the dam-like projections 11 on the original array substrate 100 along the scribe line 17, and
A dam-shaped spacer 211 is provided on the opposing original substrate 200. That is, the dam-shaped projection 11 and the dam-shaped spacer 211
By abutting each other to form a support structure, a predetermined space similar to that in the pixel display region is maintained against the pressing force applied during the scribe cutting.

In this embodiment, the dam-like projection 11 is provided with the cutout portion 12 and the step portion 13. However, since the dam-like projection 11 is provided with a sufficient width, it does not have any adverse effect on the scribe. The width of the dam-like projection 11 is set to 100 μm before being halved by scribing, for example.

The method of manufacturing the liquid crystal display device of the first embodiment will be described in detail below with reference to FIGS.

First, the manufacturing process of the original array substrate 100 will be described.

(1) On the first patterned glass substrate 118, molybdenum-containing material is formed by sputtering.
A tungsten alloy film (MoW film) is deposited to a thickness of 230 nm. Then, by patterning using the first mask pattern, 176 scanning lines 111, a gate electrode 111a including the extended portion, and the scanning line 111 are provided for each rectangular area having a diagonal dimension of 2.2 inches (56 mm). And the same number of wide auxiliary capacitance lines as the above are formed.

(2) Second patterning First, oxidation of 350 nm thick forming the gate insulating film 115 is performed.
A silicon nitride film (SiONx film) is deposited. After treating the surface with hydrofluoric acid, the semiconductor film 1 of the TFT 107 is further processed.
A 50 nm-thick amorphous silicon (a-Si: H) layer for forming 36 and a 200-nm-thick silicon nitride film (SiNx film) for forming the channel protective film 121 of the TFT 107 are exposed to the atmosphere. Film formation continuously without

After applying the resist layer, the channel protection film 21 is formed on each gate electrode 111a by the backside exposure technique using the pattern of the scanning line 111 or the like obtained by the first patterning as a mask.

(3) Third patterning In order to obtain good ohmic contact, the exposed surface of the amorphous silicon (a-Si: H) layer is treated with hydrofluoric acid, and then the low resistance semiconductor film 137 is formed. 50 nm thick phosphorus-doped amorphous silicon (n ⁺
The a-Si: H) layer is deposited by the same CVD method as above.

Thereafter, a bottom Mo layer having a thickness of 25 nm, an Al layer having a thickness of 250 nm, and a thickness of 50 nm are formed by a sputtering method.
A three-layer metal film (Mo / Al / Mo) consisting of a thick top Mo layer is deposited.

Then, using the second mask pattern,
After exposing and developing the resist, a-Si: H layer, n ⁺ a-
The Si: H layer and the three-layer metal film (Mo / Al / Mo) are patterned together. By this third patterning, for each rectangular area having a diagonal dimension of 2.2 inches (56 mm),
220 × 3 signal lines 131, a drain electrode 132 extending from each signal line 131, and a source electrode 133 are created.

(4) Fourth patterning On the multilayer film pattern obtained as described above, 200 n
After depositing an interlayer insulating film 140 made of a silicon nitride film having a thickness of m, the contact hole 142 is formed by removing the interlayer insulating film 140 on the source electrode 133.

(5) Fifth Patterning (FIG. 4) After removing the resist pattern used for the fourth patterning, a positive photosensitive curable resin liquid 150a made of acrylic resin is dried by a coater. After film thickness is 2
Apply evenly to a thickness of μm. Then, after performing the exposure operation as described below, the developing operation, the post-baking, and the cleaning operation for removing the uncured resin are performed.

As shown in FIG. 4, weak exposure for forming the concave portion 156 and the step portion 13 is performed in a predetermined region.

During the exposure scanning, for example, by using a mask pattern of two sheets and removing one mask pattern after a certain exposure time, exposure is performed from the time when one mask pattern is removed in a predetermined area. Can be set to start. By performing weak exposure in a predetermined region in this manner, the recess 156 and the step 13 having a depth of 1 μm, for example, are provided.

Strong exposure is performed at places where the contact holes 152 continuous with the contact holes 142 are provided, and the resin layer does not remain.

In the region where the pixel electrode 161 is arranged, a large number of recesses 156 are provided, so that a concavo-convex pattern for giving the light scattering function to the reflective pixel electrode 161 is formed.

In the illustrated example, the thick resin film 150 serves as a flattening film that makes the thickness of the liquid crystal layer substantially uniform when assembled in a liquid crystal display device, and also functions as a pixel electrode for a signal line or the like. And play a role of improving light utilization efficiency.

In the above description, the thick resin film 150 is described as being formed of a positive photosensitive resin, but it is also possible to use a negative photosensitive resin. In this case, the areas not exposed and the areas exposed to strong are exchanged, but the areas exposed to weak are exactly the same.

Further, in the above description, a step is provided in the integrated exposure amount by using two mask patterns, but so-called halftone patterning, which uses a mask pattern having a mesh pattern in a predetermined area, is adopted. Therefore, a step can be provided in the integrated exposure amount.

The recess 156 can also be provided by providing the integrated exposure amount with an inclination by controlling the exposure or the like. At this time, the surfaces of both edges of the dam-like projection 11 do not have a step and are gentle. Can be an inclined surface.

(6) Aluminum having a thickness of 100 nm (Al) is formed by the sixth patterning sputtering method.
After depositing the layer, a resist pattern is formed using the fifth mask pattern, and then the resist pattern is removed by ashing. Then, the pixel electrode 161 and the connection pad 15 are formed by patterning by dry etching.

At this time, since the step portion 13 is provided on the dam-like projection 11, the aluminum (Al) layer at both edges of the dam-like projection 11 is not significantly thicker than the other layers. Further, the resist pattern does not partially remain after the ashing. Therefore, the Al layer does not remain on both edges of the dam-like protrusion 11 after the ordinary etching operation.

Further, even when the sufficient step portion 13 is not formed due to the process variation or the like, the existence of the sufficient size of the cutout portion 12 causes a gap between the adjacent connection pads 15 and the adjacent terminals connected thereto. The short circuit at is sufficiently prevented.

Next, the manufacturing process of the counter original substrate 200 will be briefly described.

First, the pattern of the light shielding layer 201 is formed. The light-shielding layer 201 has a portion in the pattern of the sealing material 400 that shields each TFT 107 from light, and the columnar spacer 20.
1 is provided at a location along with the scribe line 16.

Next, red (R), blue (B), and green (G) color filter layers 20 are formed on the respective pixel dots.
Patterning is performed three times to allocate and arrange 2, 203 and 204. At the same time, the three color filter layers 202, 20 are formed on the light shielding layer 201 at a predetermined position.
The columnar spacer 201 and the dam-shaped spacer 211 are formed by stacking 3,204.

After that, an ITO film 205 forming a counter electrode is provided inside the pattern of the sealing material 400.

After the array original substrate 100 and the counter original substrate 200 are prepared in this manner, a sealing material is applied to any one of the original substrates, pressure-bonded and cured, and then cut out by scribe as described above. Be seen. After cutting out,
After the display panel body 10 is created by injecting the liquid crystal material and sealing the injection port, mounting the TCP and the drive circuit board,
Then, the liquid crystal display device is completed through the assembling of the front light device.

Next, Examples 2 to 3 will be described with reference to FIGS.

As shown in FIG. 5, the display panel body 10A according to the second embodiment has the same structure as that of the first embodiment except that the step portion 13 is omitted from the dam-like projection 11. With such a configuration, the metal layer 18 may remain in the form of streaks along the edge of the dam-like projection 11 on the inner side of the substrate, but the residual metal layer 18 is connected due to the existence of the punched portion having a sufficient width. Since each pad 15 is divided, even when a terminal group such as TCP is covered and connected, a short circuit does not occur between the terminals.

As shown in FIG. 6, the display panel body 10B according to the third embodiment has the same structure as that of the first embodiment, but the dam-like projection 11 is not provided with the cutout portion 12.
Even with such a configuration, the formation of the residual metal layer 18 at the edge of the dam-like projection 11 on the inner side of the substrate can be sufficiently prevented by providing the sufficient step portion 13.

Finally, a comparative example will be described with reference to FIG.

In the display panel body 10 'according to the comparative example,
In the same configuration as the above embodiment,
Neither the cutout portion 12 nor the step portion 13 is provided.

As shown in FIG. 7, the residual metal layer 18 which is continuous in a stripe shape is formed at a portion along the row of the connection pads 15.
May be formed. TC on the row of connection pads 15
When a terminal group such as P is connected, adjacent terminals come into contact with the residual metal layer 18 to cause a short circuit.

In the above embodiments, the reflection type liquid crystal display device has been described as an example, but the same applies to the case of a transmission type liquid crystal display device.

[0066]

EFFECT OF THE INVENTION Not only the distortion of the substrate and the display failure due to the steps of laminating and cutting out the substrate can be prevented, but also the short circuit between the connection pad and the terminal connected thereto can be sufficiently prevented. it can.

[Brief description of drawings]

FIG. 1 is a schematic partial cross-sectional perspective view of an edge portion of a display panel body for explaining a main part of a liquid crystal display device according to a first embodiment.

FIG. 2 is a plan view showing a large-sized bonded substrate obtained by bonding an array original substrate and a counter original substrate before being cut out.

FIG. 3 is a schematic laminated sectional view of the large-sized bonded substrate of FIG.

FIG. 4 is a schematic laminated sectional view for explaining a step of forming a thick resin film on an original array substrate.

5 is a partial cross-sectional perspective view corresponding to FIG. 1 for explaining a main part of the liquid crystal display device of Example 2. FIG.

FIG. 6 is a partial cross-sectional perspective view corresponding to FIG. 1 for explaining a main part of the liquid crystal display device of the third embodiment.

FIG. 7 is a partial cross-sectional perspective view corresponding to FIG. 1 for explaining a main part of a liquid crystal display device of a comparative example.

[Explanation of symbols]

10 Display panel body 11 Embankment-like protrusions on the edge of the array substrate 12 Extraction part of dam-like projection 13 Steps (shoulders) of dam-like projections 15 connection pad 16 scribe line

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinji Yamakawa             8 East Shinsugita-cho, Isogo-ku, Yokohama-shi, Kanagawa             Shiba Electronics Engineering Co., Ltd. F-term (reference) 2H088 FA02 FA03 FA04 FA05 HA02                       HA08 MA17                 2H089 KA10 LA09 LA13 LA41 NA05                       NA15 QA12 QA14 TA03 TA09                 2H092 GA40 JA24 JA37 JA46 JB22                       JB31 KA05 KA10 MA13 MA18                       MA27 NA29 PA03 PA04

Claims (5)

[Claims] 1. A first and a second substrate bonded together via a spacer and a sealing material, a liquid crystal layer held between them, and a connection pad arranged on a peripheral edge for connection of the first substrate. In the liquid crystal display device including: a dam-like projection is provided at an edge of the pattern formation surface of the first substrate, and the dam-like projection is adjacent to the connection pad in a region along the row of the connection pad. A liquid crystal display device characterized by being omitted for each gap between. 2. The liquid crystal display device according to claim 1, wherein a step portion is provided at an edge of the dam-like projection inside the substrate in a region along the row of the connection pads. 3. A first and a second substrate bonded together via a spacer and a sealing material, a liquid crystal layer held between them, and a connection pad arranged at a connection peripheral portion of the first substrate. In a liquid crystal display device including: a dam-like projection provided at an edge of the pattern formation surface of the first substrate, and a step along the edge of the dam-like projection inside the substrate in a region along the row of the connection pads. A liquid crystal display device, which is provided with a section. 4. The first substrate has a thickness of 1 including a dam-like projection.
a resin film forming step of forming a resin film pattern of μm or more; a step of forming a conductive layer pattern including a pattern of the resin film and a row of connection pads; and sealing the first substrate and the second substrate. A step of pasting through a material, and a state in which the first substrate and the second substrate are pasted together,
A substrate cutting step of cutting the first substrate and the second substrate along the dam-like projections, and electrically connecting a terminal group of a flexible wiring substrate to the row of the connection pads through a conductive adhesive means. A method for manufacturing a liquid crystal display device, comprising: a step along a row of the connection pads, wherein the dam-shaped projections are omitted for each gap between the adjacent connection pads. A method for manufacturing a characteristic liquid crystal display device. 5. The thickness including the dam-like protrusions is 1 on the first substrate.
a resin film forming step of forming a resin film pattern of μm or more; a step of forming a conductive layer pattern including a pattern of the resin film and a row of connection pads; and sealing the first substrate and the second substrate. A step of pasting through a material, and a state in which the first substrate and the second substrate are pasted together,
A substrate cutting step of cutting the first substrate and the second substrate along the dam-like projections, and electrically connecting a terminal group of a flexible wiring substrate to the row of the connection pads through a conductive adhesive means. A method of manufacturing a liquid crystal display device, comprising: a step or an inclination at the two edges of the dam-like projection with respect to the integrated intensity of exposure of an area to be exposed in the resin film forming step, According to the aspect, a step is provided at both edges of the dam-like projection, or the inclination angle of the end face of the both edges is reduced, and at the same time, a concavo-convex pattern is formed in the pixel electrode arrangement region. A method for manufacturing a liquid crystal display device.