JP3279929B2 - Liquid crystal display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a display device using a liquid crystal layer as a display medium.

[0002]

2. Description of the Related Art FIG. 4 shows a thin film transistor (hereinafter referred to as TF).
An active matrix substrate (TFT) which is a part of a liquid crystal display device using T as a switching element
1 shows an example of the configuration of a substrate. On the active matrix substrate, TFTs 2 and picture element capacitors 1 connected to the TFTs 2 are formed in a matrix. Gate signal line 3 is T
The TFT 2 is connected to the gate electrode of the FT 2, and is driven by a signal input from the input terminal 3 a and given to the gate electrode. The source signal line 5 is connected to the source electrode of the TFT.
The video signal input from a is provided. One terminal of the picture element electrode and the picture element capacitance 1 is connected to the drain electrode of the TFT 2. The other terminal of each pixel capacitor 1 is connected to an additional capacitance line 4 and connected to a counter electrode on the counter substrate when the active matrix substrate and the counter substrate are bonded together. When an active matrix substrate and a counter substrate are attached to each other with a liquid crystal layer interposed therebetween, a liquid crystal display device is obtained.

In order to realize a color display in this liquid crystal display device, R, G, B
The most common configuration is to form a color filter composed of three color filter sections. In this case, the counter substrate generally has a structure in which a black matrix is formed in order to prevent color mixture and light leakage. The black matrix is provided at the boundary of each picture element to block light leakage from a portion of the picture element where no voltage is applied to the liquid crystal layer, and is provided at the periphery of the display area to block light in the peripheral area. Also do. FIG. 5 shows a state in which the active matrix substrate 10a shown in FIG. 4 and the counter substrate 10b are bonded together. FIG. 5 does not show the pixel capacitance 1, the TFT 2, and the additional capacitance wiring 4 on the active matrix substrate 10a for simplification of the drawing. Further, the black matrix provided at the boundary between the picture elements in the display area 100 on the counter substrate 10b is omitted, and only the black matrix 30 provided at the peripheral part of the display area 100 is shown. Such a peripheral black matrix 30 is indispensable to enhance the quality as a display device. Although not shown in FIG. 5, an appropriate margin is provided between the black matrix 30 in the peripheral region and the edge of the counter substrate 10b.

[0004]

As described above, in the conventional color liquid crystal display device, the black matrix 30 is formed on the counter substrate 10b together with the filter patterns (not shown) of R, G, and B colors. It is formed. Eliminating the process for forming the black matrix 30 is an effective means for reducing the manufacturing cost of the liquid crystal display device. Therefore, development of a liquid crystal display device that does not require the formation of the black matrix 30 on the counter substrate is required. However, for that purpose, it is necessary to eliminate light leakage from the periphery of the display area without using a black matrix on the color filter substrate.

[0005] When the black matrix 30 is formed using a resin, the black matrix 30 is formed as a black matrix. D. The black matrix made of resin is formed of metal because the value is not sufficient and the black matrix made of resin is less reliable than the black matrix made of metal. However, when the black matrix 30 is formed from a light-shielding metal, there are the following problems.

[0006] The active matrix substrate 10a and the opposing substrate 10b are bonded together with a sealing resin applied to a peripheral region on one of the substrates. In the peripheral region, an electric field is generated between the black matrix 30 provided on the counter substrate 10b and the gate signal lines 3 and the source signal lines 5. For this reason, the black matrix 30 located outside the region to which the sealing resin is applied in the peripheral region is used.
Causes an electrochemical reaction with moisture in the air and corrodes.

On the other hand, the black matrix provided in the peripheral area outside the display area 100 needs to have a certain width. This is because if there is no certain width, the assembly accuracy must be increased, which leads to an increase in assembly cost. Usually, the width of the black matrix is required to be about 2.5 mm in the peripheral area.
As a result, there has been a limitation on the reduction of the peripheral region, which can be considered as a method for realizing a lightweight and compact design due to the above-mentioned corrosion.

The present invention has been made in view of such circumstances, and an object thereof is to prevent light leakage from the peripheral area without providing a black matrix in the peripheral area of the display area on the counter substrate. It is an object of the present invention to provide a liquid crystal display device having a high reliability and a highly reliable light shielding film, and capable of reducing the outer shape.

[0009]

A liquid crystal display device according to the present invention has a display area and a peripheral area surrounding the display area, and a pair of opposed substrates and a liquid crystal sandwiched between the pair of substrates. A switching element arranged in a matrix, a gate signal line for driving the switching element, and a gate signal line for driving the switching element. A source signal line for inputting a display signal to an element is formed such that the gate signal line and the source signal line are orthogonal to each other and the switching elements are respectively located near intersections; A metal light-shielding portion is formed in the one peripheral region, thereby achieving the above object.

[0010] The light-shielding portion may be formed of the same material as a material forming at least one of the gate signal line and the source signal line.

The light-shielding portion is formed so as to be patternwise separated from one of the gate signal line and the source signal line, and a part of a region between the light-shielding portion and the one signal line is
The light-shielding part and the one signal line may be shielded from light by another light-shielding part formed of a different material.

[0012] The other light-shielding portion may be formed of the same material as the other of the gate signal line and the source signal line.

The light-shielding portion is formed so as to be separated from one of the gate signal line and the source signal line in a pattern, and an outermost picture element electrode of the display area overlaps a part of the light-shielding portion. You may.

[0014] A region of the outermost picture element of the display area surrounded by the gate signal lines and the source signal lines may be smaller than a corresponding area of a picture element inside the display area.

[0015] The outermost gate signal line or source signal line of the display area and the light-shielding portion may be integrally formed, and the outermost picture element of the display area may perform black display.

The color filter layer, the protective film, the counter electrode, and the alignment film may be formed on the counter substrate, or the metal light-shielding portion may not be formed.

The area where the outermost picture element electrode of the display area overlaps the gate signal line is different from the area where the other picture element electrode of the display area overlaps the gate signal line. You may.

The dimensions of the switching element corresponding to the outermost picture element in the display area may be different from the dimensions of the other switching elements.

The pair of substrates may be bonded to each other with a seal resin, and the metal light-shielding portion may be provided outside a region where the seal resin is applied.

Hereinafter, the operation of the liquid crystal display device of the present invention will be described.

In the liquid crystal display device according to the present invention, the light-shielding portion formed on the active matrix substrate alone can shield the peripheral portion of the display area from light at a level that does not cause a problem in actual display. As a result, it is not necessary to form a light-shielding portion on the counter substrate, and the manufacturing cost of the display device can be reduced.

Further, since the light-shielding portion provided on the active matrix substrate is protected from moisture in the air by the upper and lower layers, even if the light-shielding portion is formed outside the region where the sealing resin is applied, it is corroded. Never do.

Further, the light-shielding portions provided above the gate signal lines and in the regions where light is required to be shielded between the gate signal lines are formed above them using the same material as the source signal lines. A light-shielding portion provided for a region where light-shielding between source signal lines is required is formed using the same material as the gate signal line. Therefore, the light-shielding portion can be formed on the active matrix substrate without increasing the number of steps. Therefore, a liquid crystal display device having a reduced outer shape can be manufactured without increasing the manufacturing cost.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a liquid crystal display device according to the present invention will be described with reference to the drawings.

(Embodiment 1) In this embodiment, the display area 10
In the peripheral portion of 0, a light-shielding pattern is provided on the active matrix substrate 101, not on the opposing substrate.
FIG. 1 shows an active matrix substrate 1 according to this embodiment.
13 shows a light-shielding pattern on the image No. 01. Light-shielding portions 21 are provided on the left and right of the display area 100, and light-shielding portions 22 are provided on the upper and lower sides. As will be described later in detail, the light shielding portion 21 is formed from the same material as the source signal line 5, and the light shielding portion 22 is formed from the same material as the gate signal line 3. In addition, on the active matrix substrate, in addition to the input terminals 3a and 5a, the gate signal line 3, the source signal line 5, and the light shielding portions 21 and 22, pixel electrodes arranged in a matrix and connected to each pixel electrode. Although TFTs and the like are formed, they are omitted in FIG. 1 for simplification of the drawing.

FIG. 2 shows an active matrix substrate 101.
2 shows a cross-sectional view of the vicinity of one TFT 2. The active matrix substrate 101 has a transparent insulating substrate 11. The gate signal line 3 and the additional capacitance line 4 are formed on the transparent insulating substrate 11. The gate signal line 3 has a branch 12, which functions as a gate electrode of the TFT 2. The material of the gate signal line 3 and the additional capacitance wiring 4 is generally Ta, Mo, Al
Such a metal can be used, but in this embodiment, Ta is used.
Was used. A gate insulating film 13 and a semiconductor layer 14 are formed on the gate signal line 3 and the additional capacitance wiring 4 in this order, and the semiconductor layer 14 is patterned into a predetermined shape. Next, a channel protection layer 15 is formed so as to be located above the gate electrode 12 on the semiconductor layer 14, and the n ⁺ -Si layer 16 a is partially overlapped with the channel protection layer 15.
16 b is provided on the semiconductor layer 14. This n ⁺ −
The Si layers 16a and 16b function as a source electrode and a drain electrode, respectively.

Further, the source signal line 5 is connected to the source electrode 16
It is provided so as to be in contact with a part of “a”. In this embodiment, the source signal line 5 is connected to the transparent conductive film 1 of, for example, ITO.
7b and a metal layer 17a formed thereon was formed into a two-layer structure, and these were sequentially formed by sputtering and patterned into a predetermined shape. As a material of the metal layer 17a, Ta, Mo, Al, or the like can be generally used, but in this embodiment, Ta is used. By thus forming the source signal line 5 in a two-layer structure, the metal layer 17a
Even if a defect occurs in a part of the lower transparent conductive film 17b
Therefore, there is an advantage that disconnection of the source signal line 5 can be reduced. Also,
A wiring 18 is connected to the drain electrode 16b, and the drain electrode 16b is connected to a pixel electrode 20 described later by the wiring 18. The wiring 18 is formed of a transparent conductive film 17b used as a lower layer of the source signal line 5, and only the connection portion with the drain electrode 16b is formed of the same metal layer 17a as the source signal line 5 and the transparent conductive film 17b. It has a two-layer structure. The creation process up to this point is conventionally known.

Further, an interlayer insulating film 19 is formed over the entire surface of the substrate 11. The interlayer insulating film 19 has a contact hole for connecting the wiring 18 and a pixel electrode 20 described later, but is not shown in FIG. In the present embodiment, a photosensitive acrylic resin is applied by spin coating.
A contact hole was opened in the interlayer insulating film 19. The use of the photosensitive acrylic resin has an advantage that the formation of the interlayer insulating film 19 and the formation of the contact hole can be performed simultaneously.

On the interlayer insulating film 19, a transparent conductive film is formed over the entire surface of the substrate 11 by sputtering.
This is patterned into a predetermined shape to form the pixel electrode 20. As described above, the pixel electrode 20 is connected to the wiring 18 connected to the drain electrode of the TFT via the contact hole penetrating the interlayer insulating film 19. At this time, a light-shielding material may be formed by sputtering, and may be patterned so as to surround the display region 100. In this case, the above-described light-shielding portions 21 and 22 are unnecessary. By providing the light-shielding film on the active matrix substrate in this manner, it is possible to eliminate a margin which had to be provided because the bonding accuracy between the active matrix substrate and the counter substrate was poor in the past.

With such a configuration, in the display area,
The picture element electrode 19 for applying an electric field to the liquid crystal layer can be overlapped with the gate signal line 3 and the source signal line 5 whose upper layer or the whole is made of metal, and the region where no signal voltage is applied to the liquid crystal layer is , Are all shielded by the gate signal line 3 and the source signal line 5. Therefore, it is not necessary to provide a plaque matrix in the display area.

Here, referring to FIG. 1 again, the light shielding portions 21 and 22 around the display area 100 will be described. Each of the light shielding portions 21 and 22 is formed of a metal film formed on an active matrix substrate. Display area 100
Are formed of the same metal layer as the metal layer used to form the source signal line 5, that is, the same metal layer as the upper metal layer 17 of the two-layer structure.
Specifically, the light-shielding part 21 is formed simultaneously with the upper layer of the source signal line 5 by patterning the metal layer 17a formed on the transparent conductive film 17b by sputtering. As described above, in the present embodiment, Ta is used as the material of the metal layer 17, so that the light shielding portion 21 is also formed of Ta.

On the other hand, the light shielding portions 22 provided above and below the display area 100 are formed using the same metal layer as the gate signal lines 3. The light shielding portion 22 is also formed at the same time as the gate signal line 3 by patterning a metal layer for forming the gate signal line 3. In the present embodiment, Ta is used as the material of the gate signal line 3 as described above, and the light shielding portion 22 is also formed of Ta.

By providing the light shielding portion for preventing light leakage from the peripheral portion of the display area 100 on the active matrix substrate 101 instead of the opposing substrate, the manufacturing cost of the display device can be reduced. In particular, the light shielding portion on the active matrix substrate 101 is
Alternatively, by forming the same material as the source signal line, the manufacturing cost of the counter substrate can be reduced without changing the manufacturing cost of the active matrix substrate, which is more effective in reducing the manufacturing cost of the display device. .

FIG. 3 is a plan view showing details of a boundary portion between the display area 100 and its peripheral portion. Here, the boundary portion on the left side of the display area 100 in FIG. 1 is shown as a representative. The TF along the line AA 'in FIG.
A cross-sectional view near T2 corresponds to FIG. 2 described above.

The light shielding portion 21 is formed of the same metal layer as the source signal line 5. In this embodiment, the source signal line 5
Has a two-layer structure of a metal layer 17a and a transparent conductive film 17b, so that the light-shielding portion 21 is formed of the same material as the metal layer 17a (here, Ta). At this time, the light shielding part 21 is
The outermost rows of the pixel electrodes 20 arranged in a matrix are formed separately from the source signal lines 5 that supply video signals. This is because if the light-shielding portion 21 is formed continuously with the source signal line 5 connected to the picture element electrode 20 in the outermost row, light leakage from between the light-shielding portion 21 and the source signal line 5 is completely prevented. However, the resistance and the parasitic capacitance of the source signal line 5 are different from those of the other source signal lines. As a result, even if the same video signal is input,
This is because deviation occurs as an actual display signal. In particular, in the case of halftone display, the display shift is conspicuous. Therefore, light leakage occurs from a portion between the light shielding portion 21 and the source signal line 5 connected to the picture element electrode 20 in the outermost row. In the present embodiment, light leakage from that portion is reduced. To prevent this, a light shielding portion 23 is formed.

However, the light-shielding portion 23 is formed at the same time as the gate signal line 3 and the additional capacitance wiring 4 by patterning the same metal layer as these. Therefore, it is necessary to separate the light shielding portion 23 from the gate signal line 3 and the additional capacitance line 4. For this reason, it is inevitable that a light leakage region remains around the intersection of the gate signal line 3 and the additional capacitance line 4 with the source signal line 5,
In the liquid crystal display device of this embodiment, by minimizing this area, light leakage is set to a level that does not affect the actual display.

By configuring the active matrix substrate as described above, the display region 100
The light leakage from the peripheral area can be reduced to a level that does not cause a problem in the display without providing the light-shielding part in the peripheral part.

In the present embodiment, the configuration of the active matrix substrate at the boundary between the display area and its peripheral area has been described by taking the left side of the display area as an example. It is possible. More specifically, in the peripheral region above the display region, the light shielding portion 22 is formed of the same metal layer as the gate signal line 3. However, for the same reason as described for the light-shielding portion 21, the gate signal line 3 for driving the pixel electrode 20 in the uppermost column is used.
And the light shielding portion 22 must be formed separately. Therefore, above the gap between the light-shielding portion 22 and the uppermost gate signal line 3, a light-shielding portion corresponding to the above-described light-shielding portion 23 is partially formed using the same material as the source signal line 5. Are formed so as to overlap the light shielding portion 22 and the uppermost gate signal line 3. However, a light leakage region remains around the intersection of the gate signal line 3 and the source signal line 5,
Since the area of this region is designed to be minimized, light leakage therefrom does not affect the display.

The right and lower sides of the display area 100 can be configured in the same manner as the left and upper sides of the display area 100. That is, on the right side of the display area 100, the light shielding portion 21 is formed separately from the rightmost wiring such as a common wiring, and the display area is formed so as to prevent light leakage from a portion between the wiring and the light shielding portion 21. What is necessary is just to form the light shielding part 23 similar to the left side of 100. The same applies to the lower side.

(Embodiment 2) Next, a second embodiment of the liquid crystal display device of the present invention will be described.

FIG. 6 shows a display area 100 in this embodiment.
It is a top view which shows the detail of the boundary part of a peripheral area. The representation of the left side of the display area as a representative is the same as in FIG.

In this embodiment, the light shielding portion 21 is formed of the same metal layer as the source signal line 5, and the source signal line 5 for driving the picture element electrodes 20 on the outermost row and the light shielding portion 21 are formed separately. This point is the same as that of the first embodiment, but is different from the first embodiment in that the picture element electrodes 6 in the outermost row are formed so as to overlap the light shielding portion 21. As a result, the light leakage area between the light-shielding portion 21 and the outermost source signal line 5 has the same display as the outermost picture element, and is not actually recognized as light leakage.

Here, the detailed configuration of the boundary between the display area and the peripheral area has been described using the left side of the display area as an example, but the same configuration can be applied to the upper side of the display area. More specifically, above the display area,
The light shielding portion 22 is formed of the same material as the gate signal line 3. The light-shielding portion 22 is formed by the uppermost row of the pixel electrodes 20.
Is formed separately from the gate signal line 3 connected to the pixel signal line, but the pixel electrode 20 in the uppermost row partially overlaps the light shielding portion 22 above the gap between the gate signal line 3 and the light shielding portion. In this case, light leakage from the gap can be made unrecognizable.

In this embodiment, the light-shielding portion 21 and the outermost source signal line 5 are formed separately, and the light-shielding portion 21 and the picture element electrode 20 are partially overlapped. The configuration in which the outer gate signal lines 3 are formed separately from each other and the light-shielding portions 22 and the pixel electrodes 20 are partially overlapped has been described.
The light-shielding portions 21 and 22 do not necessarily have to overlap the pixel electrodes. Even when the pixel electrode 20 is configured to partially overlap the gap between the light-shielding portion 21 and the source signal line 5 and the gap between the light-shielding portion 22 and the gate signal line 3, light leakage from the gap also occurs. It is needless to say that this has the same meaning as in the example described above in the sense that it is difficult to recognize.

Similarly, on the right and lower sides of the display area, the rightmost picture element electrode 20 and the light shielding section 21 are overlapped, and the lowermost picture element electrode 20 and the light shielding section 22 are overlapped. It is possible to make it impossible to recognize light leakage. Further, the pixel electrode 20 and the light-shielding portion 21 or 22 do not need to overlap, and the pixel electrode 20 overlaps the gap between the rightmost source signal line 5 and the light-shielding portion 21 or the lowermost portion. If the pixel electrode 20 overlaps with the gap between the gate signal line 3 on the side and the light shielding portion 22, light leakage can be made difficult to recognize.

Further, in the present embodiment, the shape of the picture element electrode 20 in the outermost row is a shape obtained by removing a portion located above the wiring such as the source signal line 5 as shown in FIG. 7, for example. You can also. In this case, it is possible to reduce the capacitive coupling between the pixel electrode 20 and the wiring,
As a result, the difference in display between the picture element in the outermost row and another picture element can be reduced.

However, if the shape of the picture element electrodes 20 in the outermost row is as shown in FIG. 7, the following problem may occur. The size of the picture element in the outermost row is the sum of the normal picture element pitch w and the width w ′ of the slit between the source signal line 5 and the light-shielding portion 21 and is larger than other picture elements. Therefore, the capacity of the picture element is large. As a result, depending on driving conditions or variations in the production process, only the picture elements in the outermost row become insufficiently charged, and only the outermost row is seen as a bright line in the case of halftone display.

As a countermeasure, as a method for increasing the production margin, only the outermost row of picture elements is changed in layout of picture elements from other picture elements, and w + w 'of one picture element belonging to the outermost row is changed. May be designed so as to match the width w of the picture element of another picture element. In this case, since the difference between the picture element capacities is reduced, the production margin due to the above-described problem can be increased. The same idea applies to the picture elements in the uppermost and lowermost columns of the display area. Only the picture elements in the uppermost and lowermost rows are the same as the original picture by the width corresponding to the vertical slit. If the portion corresponding to a pixel is made smaller, it is possible to increase the symmetry with other picture elements and increase the margin of the production process.

At this time, since the capacitance between the pixel and its own gate line is slightly different from other pixels, the TFT
, The amount of pull-in of the picture element potential at the time of switching is different, and a DC component is applied only to the outermost picture element, which may cause a reliability problem. However, this shift can be adjusted by changing the dimensions of the TFT only in the outermost picture element, or by changing the overlapping area between the picture element electrode provided on the resin and the gate line.

Embodiment 3 Next, a third embodiment of the liquid crystal display device of the present invention will be described.

FIG. 8 is a plan view showing details of the boundary between the display area and the peripheral area in this embodiment. Here, as in FIGS. 3 and 6, the left side of the display area is shown as a representative. In this embodiment, the shading portion 21 is formed from the same material as that of the source signal line 5 in the same manner as in the first and second embodiments, except that the shading portion 21 is formed of a source for driving the outermost picture element electrode 20 ′. It is formed integrally with the signal line 5. Further, more picture elements than actually required picture elements are formed, and a signal for constantly displaying black is input to the outermost picture element electrode 20 '. As a result, the influence of the symmetry of the outermost picture element being broken is eliminated, and light leakage between the surrounding light-shielding pattern and the display area can be reduced to a level without any problem.

Although the left side of the display area has been described here, the same configuration can be applied to the upper side of the display area. That is, the gate signal line 3 for driving the pixel electrode 20 ′ in the uppermost column and the light shielding portion 22 are integrally formed,
A signal for constantly displaying black is applied to the uppermost column of the pixel electrodes 20 '. Thus, an effect similar to the above-described effect can be obtained above the display area.
Similarly, if the rightmost and lowermost wirings such as a common wiring and the light shielding portions 21 and 22 are integrally formed with the right and lower sides of the display area, the right and lower sides of the display area are similarly formed. From the light leakage can be prevented.

As shown in FIG. 8, a TFT 2 is connected to each of the leftmost (and upper) picture element electrodes 20 'which always display black, and a display signal is written through the TFT2. . However, the gist of the present invention is not limited to this.
The same effect can be obtained when the source signal line is directly connected.

(Embodiment 4) Next, a fourth embodiment of the liquid crystal display device of the present invention will be described.

Also in this embodiment, a light shielding portion is formed on an active matrix substrate instead of forming a black matrix on a counter substrate. FIG. 9A shows a plan configuration of a display area of the active matrix substrate 201 in the present embodiment, and FIG. 9B shows a cross-sectional configuration. FIG.
12 shows a plan configuration of a peripheral region of the active matrix substrate 201, and FIG. 12 shows a cross-sectional configuration of the peripheral region. FIGS. 10 and 12 show, as an example, a case in which a gate signal line 204 and a light-shielding portion 220 for an area where light-shielding between the gate signal lines 204 needs to be provided in a peripheral region.

As shown in FIGS. 10 and 12, in this embodiment, in the peripheral region, an insulating film 205 is formed so as to cover the gate signal line 204, and is located above the gate signal line 204 in the insulating film 205. The light shielding part 220 is formed on the portion. An interlayer insulating film 211 is provided on the light shielding part 220. In the display area, as shown in FIG. 9A, the gate signal line 204 and the source signal line 209 themselves function as a light shielding portion.

As shown in FIG. 9B, the opposite substrate 202
No black matrix is formed on the glass substrate 213, and a counter electrode 215 made of a transparent conductive film is formed. When performing color display, a color filter 214 is also formed.

Hereinafter, an example of the manufacturing process of the active matrix substrate of this embodiment will be described with reference to FIGS.

A metal film used as a gate signal line 204 is deposited on an insulating substrate 203 such as a glass substrate and patterned into a predetermined shape to form the gate signal line 204. At this time, the gate electrode 204a of the TFT is also formed at the same time. As the material of the metal film, Ta, Al,
Cr, Mo, or the like can be used. In this embodiment, T
a film was formed. Subsequently, a gate insulating film 205, an i-type semiconductor layer 206, and a channel protection layer 207 are formed in this order, and the channel protection layer 207 is patterned into a predetermined shape. Next, the n ⁺ -Si
A layer 208 is deposited, and the n ⁺ -Si layer 208 and the i-type semiconductor layer 206 are patterned. Thereafter, a gap between the n ⁺ -Si layers 208 is formed by etching as shown in FIG.

Subsequently, a source signal line 209 and a drain electrode 210 connected to the source and the drain of the TFT are formed. Also in this embodiment, the source signal line 209 and the drain electrode 210 have a two-layer structure as in the first embodiment. The metal film used as the upper layers 209 b and 210 b of the source signal line 209 and the drain electrode 210 is formed on the gate signal line 204 in the peripheral region.
It is also provided above and above a region where light shielding between the gate signal lines 204 is required, and functions as a light shielding unit 220. Materials for this metal layer include Ta, Al, Cr, M
o or the like can be used.

Next, an interlayer insulating film 211 is formed over the entire surface of the substrate 203, and a contact hole is provided. With this contact hole, the drain electrode 2 of the TFT is formed.
10 and a pixel electrode 212 described later are connected. In the present embodiment, a photosensitive acrylic resin was used as the material of the interlayer insulating film 211, the film 211 having a thickness of 3 μm was formed, and a contact hole was formed in the film 211. Subsequently, the interlayer insulating film 21
A transparent conductive film to be used as the pixel electrode 212 is deposited on 1 and patterned into a predetermined shape to form a plurality of pixel electrodes 212 arranged in a matrix.
Thus, the active matrix substrate 201 is completed.

On the other hand, the counter substrate 202 is obtained by forming a color filter 214 and a counter electrode 215 made of a transparent conductive film on an insulating substrate 213 such as a glass substrate.

The active matrix substrate 201 and the opposing substrate 202 thus formed are bonded to each other after forming an alignment film (not shown) on each surface and performing an alignment process. Specifically, as shown in FIG. 14, in a state where the seal resin 217 is applied on one substrate, the opposing electrode 2 is located higher than the region where the seal resin 217 is applied.
The two substrates are bonded together such that 15 is located inside. Thereafter, a liquid crystal material is sealed between the two substrates, and a liquid crystal layer 2 is formed.
16 are formed.

In the present embodiment, as described above,
0 is formed in the peripheral region on the active matrix substrate 201 and is protected by the insulating film 211. Therefore, even if the light-shielding portion 220 is formed outside the region where the seal resin 217 is applied, the light-shielding portion 220 does not deteriorate due to moisture in the air as in the related art. Also,
By forming the light shielding unit 220 for shielding the peripheral area on the active matrix substrate 201, the light shielding unit 220 is formed.
The width of the liquid crystal display device need not be equal to or larger than a predetermined width in consideration of assembly accuracy and the like, and the outer shape of the liquid crystal display device can be reduced. Furthermore, since the light-shielding part 220 is formed from metal, a highly reliable light-shielding film can be obtained.

In the above-described example, the light shielding portion 220 for shielding light between the gate signal lines 204 in the peripheral area is provided not only on the gate signal lines 204 as shown in FIG.
It is a continuous layer located between the gate signal lines 204. However, the shape of the light blocking part 220 is not limited to this.
Since the gate signal line 204 itself is made of metal and has a light shielding function, for example, as shown in FIGS. 11 and 13, the gate signal line 204 may be formed only in a region where light shielding between the gate signal lines 204 is required. Good.

As described above, the liquid crystal display device of the present embodiment has been described by taking as an example the case where the light shielding portion 220 is formed in a region where light shielding between the gate signal lines 204 is required. Even in a region where light shielding is required, light shielding can be performed in substantially the same manner. That is, a metal layer formed by patterning the same film as that of the gate signal line 204 is used as a light-shielding portion for a region where light shielding between the source signal lines 209 in the peripheral region is required. Since this metal layer is protected by the gate insulating film 205, it does not deteriorate even if it is provided outside the region to which the sealing resin is applied, similarly to the above-described light shielding portion 220. Also in this case, the shape of the metal layer functioning as a light shielding portion can be, of course, a shape other than the shapes shown in FIGS. 10 and 12, for example, the shapes shown in FIGS. 11 and 13.

In the above-described example, the light-shielding portion 220 provided for the region between the gate signal lines 204 where light-shielding is required.
A light-shielding portion (not shown) provided for a region where light-shielding is required between the source signal lines 209 is formed from different films. However, these light-shielding portions can be formed simultaneously by patterning the same film.
In this case, a metal film that is electrically insulated from the upper layer 209 b of the source signal line 209 and the pixel electrode 212 is formed above the source signal line 209.

The same signal as the signal input to the counter electrode 215 may be applied to the light shielding portion formed in the peripheral region.
Corrosion can be more effectively prevented if the opposite electrode 215 and the light-shielding portion are set to the same potential. This is particularly effective when a metal layer serving as a light shielding portion is formed on the interlayer insulating film 211.

Table 1 shows that, in the liquid crystal display device of this embodiment, the light-shielding portions 22 are also provided outside the region where the seal resin 217 is applied.
The results of the aging evaluation at 60 ° C. and 95% operation when 0 is formed are shown. In addition, for comparison, evaluation results of a conventional liquid crystal display device having a black matrix formed on a counter substrate are also shown. As a conventional liquid crystal display device, FIG.
As shown in (b), a black matrix 220 'is also formed outside the area where the sealing resin 217 is applied in order to reduce the outer shape of the liquid crystal display device. FIG. 16 schematically shows a cross-sectional configuration in the vicinity of a region where the seal resin 217 is applied in the liquid crystal display device of FIG.
FIG. 15A shows a conventional liquid crystal display device in which no measures are taken to reduce the frame.

[0070]

[Table 1]

As can be seen from this table, in the conventional liquid crystal display device, the black matrix 220 ′ located outside the area where the seal resin 217 is applied is corroded by causing an electrochemical reaction with moisture in the air. ,Disappear. For this reason, in the conventional liquid crystal display device, the black matrix 2
The frame can not be reduced by forming 20 ′ outside the region where the seal resin 217 is applied.
On the other hand, in the liquid crystal display device of the present invention, the metal layer functioning as a light-shielding film is formed on the active matrix substrate, and is protected from moisture in the air by an insulating film formed thereover. Therefore, it operates normally even after 500 hours have passed.

[0072]

As described above, in the liquid crystal display device of the present invention, since the light-shielding portion is formed on the active matrix substrate, it is not necessary to form the light-shielding portion around the display area on the counter substrate. Also, light leakage from the peripheral portion of the display area can be prevented. As a result, the manufacturing process of the counter substrate can be shortened, and the manufacturing cost of the liquid crystal display device can be reduced.

Further, by forming the light-shielding portion on the active matrix substrate instead of the counter substrate, the outer shape of the liquid crystal display device can be reduced. Further, since the light-shielding portion on the active matrix substrate is protected by the insulating film on the upper layer, even if the light-shielding portion is provided outside the region where the sealing resin is applied in the peripheral region, the corrosion which has conventionally been a problem Does not happen.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a peripheral portion surrounding a display region of an active matrix substrate in a liquid crystal display device of the present invention.

FIG. 2 is a sectional view of an active matrix substrate according to the present invention.

FIG. 3 is a plan view showing a configuration of a boundary portion between a display area and a peripheral area in the first embodiment of the liquid crystal display device of the present invention.

FIG. 4 is an equivalent circuit diagram of a general liquid crystal display device.

FIG. 5 is a plan view of the liquid crystal display device of FIG.

FIG. 6 is a plan view showing a configuration of a boundary portion between a display region and a peripheral region in a second embodiment of the liquid crystal display device of the present invention.

FIG. 7 is a plan view showing a configuration of a modification of the second embodiment of the liquid crystal display device of the present invention.

FIG. 8 is a plan view showing a configuration at a boundary portion between a display area and a peripheral area in a third embodiment of the liquid crystal display device of the present invention.

9A and 9B are diagrams showing a configuration of one picture element text in a display area in a fourth embodiment of the liquid crystal display device of the present invention, wherein FIG. 9A is a plan view, and FIG. 9B is AA of FIG. It is sectional drawing along the line.

FIG. 10 is a diagram showing a planar configuration of a peripheral region in a fourth embodiment of the liquid crystal display device of the present invention.

FIG. 11 is a diagram showing a planar configuration of a peripheral region in another embodiment of the liquid crystal display device of the present invention.

12 is a diagram showing a cross-sectional configuration of a peripheral region of the liquid crystal display device of FIG.

13 is a diagram illustrating a cross-sectional configuration of a peripheral region of the liquid crystal display device of FIG.

FIG. 14 is a cross-sectional view of the vicinity of a region where a sealing resin is applied in the liquid crystal display device of the present invention.

15A and 15B are diagrams illustrating a planar configuration near a region where a seal resin is applied in a conventional liquid crystal display device. FIG. 15A illustrates a case where a black matrix is provided inside a region where a seal resin is applied, and FIG. Indicates a case where the black matrix is provided outside the region where the sealing resin is applied.

FIG. 16 is a diagram illustrating a cross-sectional configuration of the liquid crystal display device of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Picture element capacitance 2 TFT 3 Gate signal line 4 Additional capacitance wiring 5 Source signal line 10a, 101, 201 Active matrix substrate 10b, 202 Opposite substrate 19 Interlayer insulating film 19a Contact hole 20, 20 'Pixel electrode 21, 22, 23 Light shielding part 30 Black matrix 100 Display area 203, 213 Insulating substrate 204 Gate signal line 205 Insulating film 209 Source signal line 211 Interlayer insulating film 215 Counter electrode 216 Liquid crystal layer 217 Seal resin 220 Light shielding part 220 'Black matrix

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takashi Ochi 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Shinya 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Osaka Sharp Corporation (56) References JP-A-6-289414 (JP, A) JP-A-64-9420 (JP, A) JP-A-9-160002 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02F 1/1368 G02F 1/1335 505 G02F 1/1343

Claims (9)

(57) [Claims] 1. A liquid crystal display device having a display area and a peripheral area surrounding the display area, comprising a pair of opposed substrates and a liquid crystal layer sandwiched between the pair of substrates. In the display region of one of the pair of substrates, switching elements arranged in a matrix, a gate signal line for driving the switching element, and a source signal line for inputting a display signal to the switching element are provided. The gate signal line and the source signal line are formed so as to be orthogonal to each other, and the switching elements are respectively located near the intersections. One light-shielding portion is formed, and the first light-shielding portion is formed so as to be patternwise separated from one of the gate signal line and the source signal line, and is formed between the light-shielding portion and the one signal line. Part of the area between A liquid crystal display device in which light is shielded by a second light shield formed of a material different from the light shield and the one signal line. 2. The liquid crystal display device according to claim 1, wherein the first light-shielding portion is formed of the same material as a material forming at least one of the gate signal line and the source signal line. 3. The liquid crystal display device according to claim 1, wherein the second light-shielding portion is formed of the same material as the other of the gate signal line and the source signal line. 4. A liquid crystal display device having a display region and a peripheral region surrounding the display region, comprising a pair of opposed substrates and a liquid crystal layer sandwiched between the pair of substrates. In the display region of one of the pair of substrates, switching elements arranged in a matrix, a gate signal line for driving the switching element, and a source signal line for inputting a display signal to the switching element are provided. The gate signal line and the source signal line are formed so as to be orthogonal to each other, and the switching elements are respectively located in the vicinity of the intersection, and the one peripheral region of the pair of substrates is shielded from metal by light. A light-shielding portion is formed so as to be separated from one of the gate signal line and the source signal line in a pattern, and an outermost pixel electrode of the display region is formed of one of the light-shielding portions. Overlap with department Liquid crystal display device. 5. An area of the outermost picture element of the display area surrounded by the gate signal lines and the source signal lines is smaller than a corresponding area of a picture element inside the display area.
The liquid crystal display device according to claim 4. 6. A liquid crystal display device having a display area and a peripheral area surrounding the display area, comprising a pair of opposed substrates and a liquid crystal layer sandwiched between the pair of substrates. In the display region of one of the pair of substrates, switching elements arranged in a matrix, a gate signal line for driving the switching element, and a source signal line for inputting a display signal to the switching element are provided. The gate signal line and the source signal line are formed so as to be orthogonal to each other, and the switching elements are respectively located in the vicinity of the intersection, and the one peripheral region of the pair of substrates is shielded from metal by light. A liquid crystal, wherein the outermost gate signal line or source signal line of the display area and the light-shielding part are integrally formed, and the outermost picture element of the display area performs black display. display apparatus. 7. A color filter layer on the counter substrate,
7. The liquid crystal display device according to claim 1, wherein only the protective film, the counter electrode, and the alignment film are formed. 8. An area of a portion where the outermost picture element electrode of the display area overlaps with the gate signal line is an area of a portion where the other picture element electrode of the display area overlaps the gate signal line. The liquid crystal display device according to claim 4, which is different. 9. The liquid crystal display device according to claim 4, wherein the dimensions of the switching element corresponding to the outermost picture element in the display area are different from the dimensions of the other switching elements.