JPH09230380A - Active matrix substrate and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improving an opening rate and to embody a display having high image quality. SOLUTION: This active matrix substrate has a plurality of switching elements which are arranged in a matrix form on an insulating substrate, first signal wirings which apply the signals to control these switching elements, second signal wirings which are arranged to intersect with the first wirings and apply data signals to the switching elements, interlayer insulating films 9 which are formed thereon and pixel electrodes 11 are counter electrodes 13 which are formed are formed on these interlayer insulating films 9. In such a case, the counter electrodes 13 are arranged to face the second signal wirings via the interlayer insulating films 9 along the second signal wirings. The pixel electrodes 11 are arranged along the same direction as the direction of the counter electrodes 13. The pixel electrodes 11 are the counter electrodes 13 are so alternately arranged that the pixel electrodes 11 and the counter electrodes 13 are substantially equally spaced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device having a switching element such as a thin film transistor (hereinafter referred to as TFT) and using liquid crystal or the like as a display medium, and more particularly to a structure of an active matrix substrate.

[0002]

2. Description of the Related Art An active matrix type liquid crystal display device in which TFTs are formed in a matrix on an insulating substrate such as glass and used as a switching element is expected to realize a high quality flat panel display. There is. As an effective means for achieving a wide viewing angle in a conventional active matrix type liquid crystal display device, a method of applying an electric field to a liquid crystal in a direction substantially parallel to the substrate has been proposed (for example, Japanese Patent Laid-Open No. 7-360513). Issue).

14 (a), 14 (b) and 15 show such a conventional active matrix type liquid crystal display device 20. As shown in FIG.
0 is shown. 14A and 14B show a portion of the active matrix substrate 201 corresponding to one picture element, and FIG. 15 shows a line A shown in FIG.
-A ′ active matrix type liquid crystal display device 2
00 shows a cross section.

As shown in FIG. 15, an active matrix type liquid crystal display device 200 comprises an active matrix substrate 201, a counter substrate 202, and a liquid crystal layer 17 sandwiched between both substrates. The active matrix substrate 201 includes a glass substrate 1, a gate signal line 2 formed on the glass substrate 1, a common electrode 23, a gate insulating film 3, a source signal line 8, a semiconductor layer 4, a pixel electrode 11, and a drive electrode. Have 13. The gate insulating film 3 is formed so as to cover the gate signal line 2 and the common electrode 23, and the semiconductor layer 4, the source signal line 8, the pixel electrode 11, and the drive electrode 13 are formed thereon.

As shown in FIGS. 14A and 14B, the source signal line 8 has a branch 8'at a portion where the source signal line 8 intersects with the gate signal line 2, and the gate signal line 8 has a branch 8 '. 2 as a gate electrode, the branch portion 8 ′ as a source electrode, and the pixel electrode 11 as a drain electrode, the switching element (TF
T) 203 is configured. The drive electrode 13 is made of the same material as the pixel electrode 11. Drive electrode 13
Are connected to the common electrode 23 through the contact holes 10.

A protective insulating film 24 is formed so as to cover the source signal line 8, the pixel electrode 11, the driving electrode 13, and the switching element 203, and the alignment film 16 is formed thereon. The common electrode 23 and the pixel electrode 11 are the gate insulating film 3
And the auxiliary capacitance is formed at this intersection.

The counter substrate 202 includes the substrate 14 and the substrate 14
The alignment film 16 formed on the active matrix substrate 201 side and the deflection plate 12 formed on the outer side.

In such an active matrix type liquid crystal display device 200, the liquid crystal layer 17 is driven by an electric field formed in a direction substantially parallel to the substrate surface (horizontal electric field drive system). As shown in FIG. 14A, the liquid crystal molecules 25 have a slight angle (0 degree or more and less than 15 degrees) with respect to the longitudinal direction of the picture element electrode 11 and the drive electrode 13 in a state where no voltage is applied. Oriented. Picture element electrode 11
When a voltage is applied between the drive electrode 13 and the drive electrode 13, as shown in FIG.
As shown in (b), the liquid crystal molecules 25 are aligned along the electric field E directed from the pixel electrode 11 to the drive electrode 13.

[0009]

In the horizontal electric field driving type liquid crystal display device 200 as described above, the common electrode 2 is used.
Since 3 and its driving electrode 13 are arranged on the TFT substrate side, the active matrix substrate side is provided as compared with the conventional vertical electric field driving type liquid crystal display device in which the common electrode (driving electrode) is arranged on the counter substrate side. The wiring structure of the electrode becomes complicated. Therefore, there is a problem that crosstalk easily occurs due to the parasitic capacitance between the wirings. Further, in the case of a transmissive other liquid crystal display device, the presence of the common electrode and the drive electrode narrows the area of the opening through which the backlight light passes, so that sufficient luminance cannot be obtained.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to (1) increase the area of the opening of the display region to achieve high-luminance display or low power consumption. Provide a liquid crystal display device that can be realized,
(2) To provide a liquid crystal display device that realizes a high-quality display by reducing the display unevenness and the difference due to the viewing angle by arranging the picture element electrode and the counter electrode substantially at equal intervals, and (3) the picture. An object of the present invention is to provide a liquid crystal display device that realizes high-quality display with reduced crosstalk by suppressing the influence of the source signal line on the element electrodes.

[0011]

An active matrix according to the present invention includes an insulating substrate, a plurality of switching elements arranged in a matrix on the insulating substrate, and a signal for controlling the switching element. And a second signal wiring which is arranged so as to intersect with the first wiring and which supplies a data signal to the switching element, the switching element and the first and second signal wirings. An interlayer insulating film formed so as to cover the interlayer insulating film and having a contact hole, a pixel electrode formed on the interlayer insulating film and electrically connected to the switching element through the contact hole, and an interlayer insulating film on the interlayer insulating film. And a formed counter electrode. In the active matrix substrate, the counter electrode is arranged along the second signal wiring so as to face the second signal wiring via the interlayer insulating film, and the pixel electrode is arranged to face the counter electrode. The picture element electrodes and the counter electrodes are arranged along the same direction, and the picture element electrodes and the counter electrodes are alternately arranged so that the picture element electrodes and the counter electrodes are at substantially equal intervals, whereby the above object is achieved. Is achieved.

In one embodiment, one picture element region corresponding to each switching element includes at least one picture element electrode, and each picture element electrode is sandwiched by two counter electrodes.

In the adjacent picture element regions, the boundary between two picture element electrodes adjacent to each other along the direction is preferably formed on the first signal wiring.

Preferably, the width of the counter electrode is the second electrode.
Is wider than the width of the signal wiring, and the wiring width of the counter electrode is formed so as to completely cover the second signal wiring.

The counter electrode is interleaved with the interlayer insulating film,
It may be formed on all the second signal wirings.

The active matrix substrate may further have a counter electrode arranged between the picture element electrodes, in addition to the second signal wiring.

The counter electrodes are preferably connected to each other outside the display region and have the same electric potential.

The active matrix substrate has a common electrode which is arranged so as to intersect with the pixel electrode and forms an auxiliary capacitance between the pixel electrode and the pixel electrode, and the counter electrode is the common electrode. May be electrically connected to.

In one embodiment, the interlayer insulating film includes a first insulating layer made of an insulating film of three colors forming a color filter, and a second insulating layer formed so as to cover the first insulating layer. And an insulating layer.

The color filter may be formed by patterning a film-shaped resin having photosensitivity of three colors.

The pixel electrode is electrically connected to the switching element through a first contact hole formed in the first insulating layer and a second contact hole formed in the second insulating layer. It may be connected.

The first contact hole is preferably formed so that its width is smaller than the width of the common electrode and completely overlaps with it, and the second contact hole has a width of the first contact hole. It is formed so as to be smaller than the width of the contact hole and inside the first contact hole.

A liquid crystal display device of the present invention comprises the above active matrix substrate, a counter substrate having a transparent insulating substrate, and a liquid crystal layer sandwiched between the active matrix substrate and the counter substrate. Therefore, the above object is achieved.

In one embodiment, the liquid crystal display device of the present invention is sandwiched between the active matrix substrate, the counter substrate having a mirror-like reflective surface, and the active matrix substrate and the counter substrate. And a liquid crystal layer, which achieves the above object.

In another embodiment, a liquid crystal display device of the present invention controls a first insulating substrate, a plurality of switching elements arranged in a matrix on the insulating substrate, and the switching elements. A first signal wiring for supplying a signal to the switching element and a second signal wiring arranged to intersect with the first wiring and supplying a data signal to the switching element, the switching element and the first signal wiring. And an insulating film formed so as to cover the second signal wiring and having a contact hole, and formed on the insulating film,
An active matrix substrate having a pixel electrode electrically connected to the switching element through the contact hole, a second insulating substrate, and a counter electrode formed on the second insulating substrate. And a liquid crystal layer sandwiched between the active matrix substrate and the counter substrate. In the liquid crystal display device, the counter electrode is arranged along the second signal line with the liquid crystal layer sandwiched therebetween and so as to face the second signal line, and the pixel electrode is The pixel electrodes and the counter electrodes are arranged along the same direction as the counter electrodes and are alternately arranged so that the pixel electrodes and the counter electrodes are arranged at substantially equal intervals, whereby the above object is achieved.

The counter substrate may have a color filter formed on the second insulating substrate.

The operation will be described below.

Since the picture element electrode and the counter electrode are formed so as to be substantially equidistant from each other, the picture element electrode is arranged substantially at the center of the two counter electrodes. As a result, the electric field formed in each picture element region becomes substantially equal on both sides of the picture element electrode, and the difference in viewing angle and display unevenness in each picture element region are reduced. Further, when a plurality of picture element electrodes and corresponding common electrodes are arranged in one picture element region, the pitch between the electrodes is reduced, and display can be performed with a lower driving voltage.

Further, in the adjacent picture element regions, the boundary between two adjacent picture element electrodes is formed on the first signal wiring (gate signal line), so that the separated portions of the picture element electrodes which do not contribute to the display are formed. The aperture ratio can be improved because it is arranged on the first signal wiring and there is no need to separately provide a light shielding part.

The counter electrode is formed along the second signal line (source signal line) so that the width of the counter electrode is wider than the width of the second signal line and completely covers the second signal line. It is formed. As a result, the second signal wiring is arranged so as to be completely contained within the wiring width of the counter electrode, so that the wiring width of the second signal wiring does not occupy the opening portion excessively and the area of the opening portion is not occupied. Will increase.

One picture element region corresponds to a region surrounded by two first signal wirings and two second signal wirings. Therefore, when one picture element electrode is arranged in each picture element region, all the counter electrodes are formed on the second signal wiring. When a plurality of picture element electrodes are arranged in each picture element region, the counter electrode is on all the second signal wirings,
Further, it is formed in a region between the second signal wirings. The counter electrode formed in the region between the second signal wirings is arranged between the pixel electrodes.

Further, by forming the counter electrode so as to completely cover the second signal wiring with the interlayer insulating film interposed therebetween,
The electric field formed by the second signal wiring line is shielded by the counter electrode (shield effect). In particular, by arranging the counter electrode three-dimensionally between the liquid crystal layer and the second signal wiring, it is possible to more effectively shield the influence of the electric field generated by the second signal wiring on the liquid crystal layer. . As a result, the alignment disorder of the liquid crystal molecules can be prevented and crosstalk can be suppressed.

Further, by providing a common electrode intersecting with the pixel electrode and electrically connecting this common electrode to the counter electrode which has the same potential, an auxiliary capacitance is provided between the pixel electrode and the common electrode. It can be formed.

Further, when the color filter is formed by using the interlayer insulating film and the color filter is provided on the active matrix substrate side, it is possible to avoid the reduction of the aperture ratio due to the bonding precision with the counter substrate.

When the counter electrode is formed on the counter substrate side with the liquid crystal layer interposed therebetween, parasitic capacitance can be reduced, and when the counter substrate is provided with a color filter, the counter electrode can be reduced. Can double as a black matrix.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to embodiments.

(Embodiment 1) FIG. 1 is a plan view of a liquid crystal display device 100 according to a first embodiment of the present invention. FIG.
1A shows a cross section of the liquid crystal display device 100 taken along the line AA ′ shown in FIG. 1, and FIG. 2B shows a cross section taken along the line BB ′ shown in FIG. ing. As shown in FIGS. 2A and 2B, the liquid crystal display device 100 includes an active matrix substrate 101, a counter substrate 102, and a liquid crystal layer 17 sandwiched between the active matrix substrate 101 and the counter substrate 102. I have it.

First, the basic structure of the active matrix substrate 101 will be described. As shown in FIGS. 1 and 2A, in the active trix substrate 101,
On the transparent insulating substrate 1 such as glass, the gate signal line 2,
A gate electrode 2 ′ and a common electrode 15 branched from the gate signal line 2 are formed. A source signal line 8 is formed thereon so as to intersect the gate signal line 2 and the common electrode 15 with the gate insulating film 3 interposed therebetween. A picture element electrode 11 and a counter electrode 13 are formed thereon with an interlayer insulating film 9 interposed therebetween. The pixel electrode 11 and the counter electrode 13 intersect the gate signal line 2 and the common electrode 15 ′, and each counter electrode 13 is formed along the corresponding source signal line 8.

As shown in FIG. 1, the picture element electrodes 11 and the counter electrodes 13 are alternately arranged so that the picture element electrodes 11 and the counter electrodes 13 are substantially equidistant from each other.
In this embodiment, one picture element area (unit display area)
Is a region surrounded by two gate signal lines 2 and two source signal lines 8 (and the counter electrode 13 overlapping the source signal line 8 via the interlayer insulating film 9), and each pixel region Includes a pixel electrode 11 arranged in the center. A portion 31 (FIG. 2A) that separates two adjacent pixel electrodes 11 (vertical direction in FIG. 1) is provided on the gate signal line 2. By forming the separation portion 31 in this way, the boundary area of each picture element can be minimized and the aperture ratio can be improved.

At the intersection of the source signal line 8 and the gate signal line 2, a TFT 30 is formed as a switching element so as to correspond to each picture element region. As shown in FIG. 2B, the TFT 30 includes a gate electrode 2 ′, a gate insulating film 3, a semiconductor layer 4, a gate electrode 2 ′ formed on the transparent substrate 1.
The semiconductor layer 4 has a channel protection layer 5 formed in the center thereof and contact layers 6a and 6b formed on both sides of the channel protection layer 5. The source signal line 8 and the lower transparent conductive film 7a are connected to the contact layer 6a so as to overlap each other. This overlapping portion becomes the source electrode 8a.
The drain electrode 8b and the lower transparent conductive film 7b are connected to the contact layer 6b so as to overlap each other. TFT3
An interlayer insulating film 9 is formed so as to cover 0, the gate signal line 2, and the source signal line 8.

As shown in FIGS. 1 and 2A, the transparent conductive film 7b extends along the pixel electrode 11 formed on the transparent conductive film 7b and faces the common electrode 15 via the gate insulating film 3. ing. In the portion where the transparent conductive film 7b faces the common electrode 15, the pixel electrode 11 is electrically connected to the transparent conductive film 7b through the contact hole 10 provided in the interlayer insulating film 9.

As shown in FIG. 3, all the counter electrodes 13
Are connected to each other in a portion 13 'outside the display area of the insulating substrate 1 and have the same potential. The counter electrode 13 is
The contact hole 1 in the portion 13 ′ outside the display area
It is connected to the common electrode 15 through 0 '. In this way, the common electrode 15 and the transparent conductive film 7b having the same potential as the pixel electrode 11 form an auxiliary capacitance.

Next, a method of manufacturing the liquid crystal display device 100 will be described with reference to FIGS. 1, 2A and 2B.
First, in the active matrix substrate 101, the gate signal line 2, the gate electrode 2 ′, and the common electrode 15 are formed on the transparent insulating substrate 1 by patterning a metal layer such as Ta or Al. The thickness of the metal layer is about 36
00-6500Å is preferable. A gate insulating film 3 is formed on the entire insulating substrate 1 so as to cover the gate signal line 2, the gate electrode 2 ′ and the common electrode 15. The gate insulating film is, for example, about 3000 to 5000 Å SiNx, S
iO ₂ or the like can be used.

Next, the semiconductor layer 4 is formed on the gate insulating film 3 so as to face the gate electrode 2 '. As the semiconductor layer 4, a-Si, p-Si, or the like can be used. The thickness of the semiconductor layer 4 is preferably about 300 to 500Å. A channel protection layer 5 is patterned on the central portion of the semiconductor layer 4. As the channel protective layer, for example, about 1
A 000Å SiNx layer or the like can be used. next,
Contact layers 6a (source electrode side) and 6b (drain electrode side) made of an n ⁺ -Si layer of about 700 Å are formed so as to overlap with both ends of the channel protection layer 5 and cover the semiconductor layer 4.

A transparent conductive film such as ITO is formed thereon by sputtering and patterned to form a transparent conductive film 7a as a lower layer of the source signal line and a source electrode, and a common electrode 1 as a lower layer of the drain electrode.
A transparent conductive film 7b extending toward 5 is formed. A metal layer 8 of Ta, Al or the like is formed thereon by sputtering to a thickness of about 3600 to 6500Å, and is patterned to form the upper layer 8 of the source signal line, the source electrode 8a, and the drain electrode 8b. In this embodiment, as shown in FIG. 2B, the source signal line 8'having a two-layer structure is formed by the upper metal layer 8 and the lower transparent conductive film 7a. In this way, by forming the source signal line 8 ′ in a two-layer structure, even if a part of the upper metal layer 8 is damaged, the source signal line 8 ′ is electrically connected by the lower transparent conductive film 7 a. , Source signal line 8 '
There is an advantage that the disconnection of can be reduced.

Next, an interlayer insulating film 9 is formed by using, for example, a photosensitive acrylic resin so as to cover the TFT 30, the gate signal line 2, the source signal line 3, and the transparent conductive film 7b. In the step of forming the interlayer insulating film 9, the contact hole 10 is simultaneously formed by exposure and alkali development. The thickness of the interlayer insulating film 9 is about 3 μm. The larger the opening area of the contact hole 10, the better. Preferably, the width of the contact hole 10 is smaller than the width of the common electrode 15 and is formed so as to completely overlap. The interlayer insulating film 9 may be formed using a resin such as polyimide.

Next, a metal layer of Ta, Al, or the like is sputtered on the inter-layer insulating film 9 to a thickness of about 5000 to 700.
The pixel electrode 11 and the counter electrode 13 are formed by forming the pixel electrode 11 and the counter electrode 13 with a thickness of 0Å and patterning. Picture element electrode 11
Are electrically connected to the transparent conductive film 7b connected to the drain electrode 8b through a contact hole 10 formed in the interlayer insulating film 9. In this embodiment, the picture element electrodes 11 and the counter electrodes 13 are alternately arranged in the same direction, and the picture element electrodes 11 and the counter electrodes 13 are arranged at substantially equal intervals. In this embodiment, the counter electrode 13 is formed so as to face all the source signal lines 8 in the display screen with the interlayer insulating film 9 interposed therebetween. Further, the counter electrode 13 is formed so that its width is wider than that of the source signal line 8 and completely covers the source signal line 8.

On the other hand, in the counter substrate 102, a color filter 14 of each color of red, green and blue is formed by applying a photosensitive color resist on the transparent insulating substrate 12, exposing and developing it. After that, the alignment film 16 is formed on each of the active matrix substrate 101 and the counter substrate 102. Then, the substrates 101 and 102 are bonded to each other with a predetermined gap, and a liquid crystal material is injected into the gap to form the liquid crystal layer 17. In this way, the liquid crystal display device 100 is completed.

4A and 4B show how the liquid crystal layer 17 is driven by the liquid crystal display device 100 manufactured as described above. 4A shows a state in which no voltage is applied, and FIG. 4B shows a state in which voltage is applied. As shown in FIG. 4A, the liquid crystal molecules 25 are oriented so as to form a slight angle (0 degrees or more and less than 15 degrees) with respect to the longitudinal direction of the pixel electrode 11 and the drive electrode 13. When a voltage is applied between the picture element electrode 11 and the drive electrode 13, an electric field E is formed in a direction substantially parallel to the substrate surface as shown in FIG.
To the drive electrode 13. In this embodiment, the pixel electrode 11 is composed of two counter electrodes 13.
The electric field E formed in each picture element region is substantially equal on both sides of the picture element electrode 11 because it is arranged substantially in the center. Therefore, it is possible to reduce the difference in the viewing angle and the display unevenness in each picture element region, and to realize a high-quality display.

As described above, in this embodiment, the counter electrode 13 is formed along the source signal line 8, and the source signal line 8 is arranged so as to be completely contained within the wiring width of the counter electrode 13. Therefore, the wiring width of the source signal line 8 does not excessively occupy the opening, and the area of the opening can be increased. Further, by disposing the separated portion 31 of the pixel electrode 11 on the gate signal line 2, the aperture ratio can be further improved. As a result, the area of the opening through which the backlight light passes can be increased, so that it is possible to provide a high-brightness liquid crystal display device using the conventional backlight, and realize the conventional brightness with less power consumption. A liquid crystal display device can be provided.

Further, as described above, by forming the counter electrode 13 so as to completely cover the source signal line 8 with the interlayer insulating film 9 interposed therebetween, the electric field formed by the source signal line 8 is applied. Can be shielded by (shield effect). In particular, the counter electrode 13 is the liquid crystal layer 1
7 and the source signal line 8 are arranged three-dimensionally,
The influence of the electric field generated by the source signal line 8 on the liquid crystal layer 17 can be shielded more effectively. As a result, the disturbance of the electric field formed by the source signal line 8 can be prevented, the disturbance of the alignment of the liquid crystal molecules can be prevented, and the crosstalk can be suppressed, so that a higher quality liquid crystal display device can be provided.

(Embodiment 2) FIG. 5 is a plan view of a liquid crystal display device 110 according to a second embodiment of the present invention. FIG.
5A shows a cross section of the liquid crystal display device 110 taken along the line CC ′ shown in FIG. 5, and FIG. 6B shows a cross section taken along the line DD ′ shown in FIG. ing. As shown in FIGS. 6A and 6B, the liquid crystal display device 110 includes an active matrix substrate 111, a counter substrate 112, and a liquid crystal layer 17 sandwiched between the active matrix substrate 111 and the counter substrate 112. I have it.

First, the basic structure of the active matrix substrate 111 will be described. 5, 6 (a) and 6 (b)
As shown in FIG. 3, in the active-trics substrate 111, the gate signal line 2, the gate electrode 2 ′ branched from the gate signal line 2, and the common electrode 15 are formed on the transparent insulating substrate 1 such as glass. . A source signal line 8 is formed thereon so as to intersect the gate signal line 2 and the common electrode 15 with the gate insulating film 3 interposed therebetween. A picture element electrode 11 and a counter electrode 13 are formed thereon with an interlayer insulating film 9 interposed therebetween. Picture element electrode 11 and counter electrode 13
Intersect the gate signal line 2 and the common electrode 15 '.

As shown in FIG. 5, the picture element electrodes 11 and the counter electrodes 13 are alternately arranged so that the picture element electrodes 11 and the counter electrodes 13 are substantially equidistant from each other.
In this embodiment, one picture element area (unit display area)
Is a region surrounded by two gate signal lines 2 and two source signal lines 8 (and the counter electrode 13 overlapping the source signal line 8 via the interlayer insulating film 9), and each pixel region Includes one counter electrode 13 arranged substantially in the center and two picture element electrodes 11 arranged on both sides thereof. That is, two picture element electrodes 11 included in one picture element region
Are arranged so as to be sandwiched between the counter electrodes 13. As can be seen from FIGS. 6A and 6B, the source signal line 2 is not formed below the counter electrode 13 in the center of the pixel area.

A portion 31 for separating two adjacent pixel electrodes 11 (vertical direction in FIG. 5) is provided on the gate signal line 2. By forming the separation portion 31 in this way, the boundary area of each picture element can be minimized,
The aperture ratio can be improved.

At the intersection of the source signal line 8 and the gate signal line 2, a TFT 30 is formed as a switching element so as to correspond to each picture element region. The structure of the TFT 30 according to the present embodiment is exactly the same as that of the TFT 30 according to the embodiment 1 shown in FIG. 2B, and the gate electrode 2 ′, the gate insulating film 3, the semiconductor formed on the transparent substrate 1 are formed. It has a layer 4, a channel protection layer 5 formed in the central portion of the semiconductor layer 4, and contact layers 6a and 6b formed on both sides of the channel protection layer 5. The source signal line 8 and the lower transparent conductive film 7a are connected to the contact layer 6a so as to overlap each other. This overlapping portion becomes the source electrode 8a. The drain electrode 8b and the lower transparent conductive film 7b are connected to the contact layer 6b so as to overlap each other.

As shown in FIGS. 5, 6A and 6B, the transparent conductive film 7b extends from the drain electrode 6b along one pixel electrode 11 and the common electrode via the gate insulating film 3. It is facing 15. The transparent conductive film 7 b extends along the common electrode 15 and intersects the two picture element electrodes 11 and one common electrode 13 arranged between them with the correlation insulating film 9 interposed therebetween. Each pixel electrode 11 is electrically connected to the transparent conductive film 7b at the intersection through a contact hole 10 provided in the interlayer insulating film 9.

Similar to the case of the first embodiment, all the counter electrodes 13 are connected to each other in the portion 13 'outside the display area of the insulating substrate 1 and have the same potential (FIG. 3). The counter electrode 13 is connected to the common electrode 15 through the contact hole 10 ′ in the portion 13 ′ outside the display area. In this way, the common electrode 15 and the transparent conductive film 7b having the same potential as the pixel electrode 11 form an auxiliary capacitance.

Also in this embodiment, the picture element electrodes 11 and the counter electrodes 13 are alternately arranged in the same direction.
The counter electrode 13 and the counter electrode 13 are arranged so as to be substantially equally spaced. In this embodiment, the counter electrode 13 is
It is formed so as to be opposed to all the source signal lines 8 in the display screen with the interlayer insulating film 9 interposed therebetween, and is also arranged at substantially the center of the pixel region. The width of the counter electrode 13 is formed so as to be wider than the width of the source signal line 8 and completely covers the wiring width of the source signal line 8. In this way, the source signal line 8 is formed so as to completely fit within the wiring width of the counter electrode 13, so that the wiring width of the source signal line 8 does not occupy the opening portion and the area of the opening portion is not occupied. Can be increased.

By forming the counter electrode 13 so as to completely cover the source signal line 8 with the interlayer insulating film 9 interposed therebetween, the electric field formed by the source signal line 8 can be shielded by the counter electrode 13. it can. In particular, since the counter electrode 13 is three-dimensionally arranged between the liquid crystal layer 17 and the source signal line 8, it is possible to more effectively shield the influence of the electric field generated by the source signal line 8 on the liquid crystal layer 17. You can As a result, the disturbance of the electric field formed by the source signal line 8 can be prevented, the disturbance of the alignment of the liquid crystal molecules can be prevented, and crosstalk can be suppressed.

In the case of this embodiment, two pixels are included in one picture element area.
Since the picture element electrode 11 of the book is included, the widths of the picture element electrode 11 and the counter electrode 13 are reduced as compared with the case of the first embodiment,
The drive voltage can be reduced. The number of picture element electrodes 11 may be three or more. Thus, a plurality of picture signal electrodes 11 and the corresponding counter electrodes 13 are provided in one picture element region.
By arranging, the pitch between the electrodes can be narrowed, and display can be performed with a lower driving voltage.

The manufacturing method of the liquid crystal display device 110 according to the present embodiment is the same as that of the liquid crystal display device 100 according to the first embodiment, and the description thereof will be omitted.

(Embodiment 3) FIG. 7 is a plan view of a liquid crystal display device 120 according to a third embodiment of the present invention. FIG.
7A shows a cross section of the liquid crystal display device 120 taken along the line AA ′ shown in FIG. 7, and FIG. 8B shows a cross section taken along the line BB ′ shown in FIG. ing. As shown in FIGS. 8A and 8B, the liquid crystal display device 120 includes an active matrix substrate 121, a counter substrate 122, and a liquid crystal layer 17 sandwiched between the active matrix substrate 121 and the counter substrate 122. I have it.

First, the basic structure of the active matrix substrate 121 will be described. As shown in FIGS. 7 and 8A, in the active trix substrate 121,
On the transparent insulating substrate 1 such as glass, the gate signal line 2,
A gate electrode 2 ′ and a common electrode 15 branched from the gate signal line 2 are formed. A source signal line 8 is formed thereon so as to intersect the gate signal line 2 and the common electrode 15 with the gate insulating film 3 interposed therebetween. On top of that, a pixel electrode 1 is provided via a color filter 18 and an interlayer insulating film 9.
1 and the counter electrode 13 are formed. The pixel electrode 11 and the counter electrode 13 are the gate signal line 2 and the common electrode 15 ′.
And each counter electrode 13 is formed along the corresponding source signal line 8.

As shown in FIG. 7, the picture element electrodes 11 and the counter electrodes 13 are alternately arranged so that the picture element electrodes 11 and the counter electrodes 13 are substantially equidistant from each other.
In this embodiment, one picture element area (unit display area)
Is a region surrounded by two gate signal lines 2 and two source signal lines 8 (and the counter electrode 13 superimposed on the source signal lines 8), and each pixel region is a picture arranged in the center. The element electrode 11 is included. Two adjacent pixel electrodes 11
A portion 31 (FIG. 8) for separating (vertical direction in FIG. 7)
(A)) is provided on the gate signal line 2. By forming the separation portion 31 in this way, the boundary area of each picture element can be minimized and the aperture ratio can be improved.

At the intersection of the source signal line 8 and the gate signal line 2, a TFT 30 is formed as a switching element so as to correspond to each picture element region. As shown in FIG. 8B, the TFT 30 includes a gate electrode 2 ′ formed on the transparent substrate 1, a gate insulating film 3, a semiconductor layer 4,
The semiconductor layer 4 has a channel protection layer 5 formed in the center thereof and contact layers 6a and 6b formed on both sides of the channel protection layer 5. The source signal line 8 and the lower transparent conductive film 7a are connected to the contact layer 6a so as to overlap each other. This overlapping portion becomes the source electrode 8a.
The drain electrode 8b and the lower transparent conductive film 7b are connected to the contact layer 6b so as to overlap each other. TFT
30, so as to cover the gate signal line 2 and the source signal line 8,
An interlayer insulating film 9'is formed.

The interlayer insulating film 9'of this embodiment is composed of an insulating film of three colors, which is formed so as to cover each picture element region and becomes the color filter 18, and the interlayer insulating film 9 formed thereon. Consists of. In the color filter 18, the insulating films of three colors are arranged in a predetermined arrangement such as stripe type or delta type. The contact hole 21 of the color filter 18 and the contact hole 10 of the interlayer insulating film 9 are provided at the same position.

As shown in FIGS. 7 and 8A, the transparent conductive film 7b extends along the pixel electrode 11 and overlaps the common electrode 15 via the gate insulating film 3. Transparent conductive film 7
In the part where b is opposed to the common electrode 15, the pixel electrode 1
1 is a contact hole 10 provided in the interlayer insulating film 9.
And, it is electrically connected to the transparent conductive film 7b through a contact hole 21 provided in the color filter 18.

Also in this embodiment, as in the case of the first embodiment, as shown in FIG. 3, all the counter electrodes 13 are connected to each other in the portion 13 ′ outside the display area of the insulating substrate 1. And are at the same potential. The counter electrode 13 is connected to the common electrode 15 through the contact hole 10 ′ in the portion 13 ′ outside the display area. In this way, the common electrode 15 and the transparent conductive film 7b having the same potential as the pixel electrode 11 are formed.
And form a storage capacitor.

Next, a method for manufacturing the liquid crystal display device 120 will be described with reference to FIGS. 7, 8A and 8B.
First, in the active matrix substrate 121, the gate signal line 2, the gate electrode 2 ′, and the common electrode 15 are formed on the transparent insulating substrate 1 by patterning a metal layer such as Ta or Al. The thickness of the metal layer is about 36
00-6500Å is preferable. Next, the gate signal line 2,
A gate insulating film 3 is formed on the entire insulating substrate 1 so as to cover the gate electrode 2 ′ and the common electrode 15. The gate insulating film is, for example, about 3000 to 5000 Å SiNx, Si
O ₂ or the like can be used.

Next, the semiconductor layer 4 is formed on the gate insulating film 3 so as to face the gate electrode 2 '. As the semiconductor layer 4, a-Si, p-Si, or the like can be used. The thickness of the semiconductor layer 4 is preferably about 300 to 500Å. A channel protection layer 5 is patterned on the central portion of the semiconductor layer 4. As the channel protective layer, for example, about 1
A 000Å SiNx layer or the like can be used. next,
Contact layers 6a (source electrode side) and 6b (drain electrode side) made of an n ⁺ -Si layer of about 700 Å are formed so as to overlap with both ends of the channel protection layer 5 and cover the semiconductor layer 4.

A transparent conductive film such as ITO is formed thereon by sputtering and patterned to form a transparent conductive film 7a as a lower layer of the source signal line and a source electrode, and a common electrode 1 as a lower layer of the drain electrode.
A transparent conductive film 7b extending toward 5 is formed. A metal layer 8 of Ta, Al or the like is formed thereon by sputtering to a thickness of about 3600 to 6500Å, and is patterned to form the upper layer 8 of the source signal line, the source electrode 8a, and the drain electrode 8b. In this embodiment, as shown in FIG. 8B, the source signal line 8'having a two-layer structure is formed by the upper metal layer 8 and the lower transparent conductive film 7a. In this way, by forming the source signal line 8 ′ in a two-layer structure, even if a part of the upper metal layer 8 is damaged, the source signal line 8 ′ is electrically connected by the lower transparent conductive film 7 a. , Source signal line 8 '
There is an advantage that the disconnection of can be reduced.

Next, a red photosensitive film-like resin is attached so as to cover the TFT 30, the gate signal line 2, the source signal line 3, and the transparent conductive film 7b, and patterning is performed by performing exposure and development. A first insulating film serving as a red filter is formed. The contact hole 21 is simultaneously formed during patterning. Similarly, green and blue photosensitive film-like resins are used to form the second and third insulating films to be the green and blue filters, respectively.
The contact hole 2 is formed by these first to third insulating films.
A color filter 18 having 1 is formed.

An interlayer insulating film 9 is formed thereon by using, for example, a photosensitive acrylic resin. In the step of forming the interlayer insulating film 9, the contact hole 10 is formed at the same position as the contact hole 21 by exposure and alkali development. The thickness of the interlayer insulating film 9 ′ including the color filter 18 and the interlayer insulating film 9 is about 3 μm. The opening areas of the contact holes 10 and 21 are preferably large. Preferably, the contact hole 21 has a width of the common electrode 15
The width is smaller than the width of and is completely overlapped.
Further, the contact hole 10 is formed inside the contact hole 21 such that its width is smaller than that of the contact hole 21. In addition, the interlayer insulating film 9
Is formed on the color filter 18, the surface of the interlayer insulating film 9 ′ can be formed flat. still,
The interlayer insulating film 9 may be formed using a resin such as polyimide.

Next, a metal layer of Ta, Al, or the like is sputtered on the inter-layer insulating film 9 to a thickness of about 5000 to 700.
The pixel electrode 11 and the counter electrode 13 are formed by forming the pixel electrode 11 and the counter electrode 13 with a thickness of 0Å and patterning. Picture element electrode 11
Are the contact holes 10 formed in the interlayer insulating film 9 and the contact holes 2 formed in the color filter 18.
1 through the transparent conductive film 7 connected to the drain electrode 8b
electrically connected to b. In this embodiment, the pixel electrodes 11 and the counter electrodes 13 are alternately arranged in the same direction,
The pixel electrodes 11 and the counter electrode 13 are arranged so that the distance between them is substantially equal. In this embodiment, the counter electrode 13 is formed so as to oppose all the source signal lines 8 in the display screen with the interlayer insulating film 9 ′ interposed therebetween.
Further, the counter electrode 13 is formed so that its width is wider than that of the source signal line 8 and completely covers the source signal line 8.

After that, the active matrix substrate 121
The alignment film 16 is formed on each of the counter substrate 122 and the counter substrate 122. Then, the substrates 121 and 122 are bonded to each other with a predetermined gap therebetween, and a liquid crystal material is injected into the gap to form the liquid crystal layer 17. In this way, the liquid crystal display device 1
20 is completed.

As described above, according to the liquid crystal display device 120 of this embodiment, the source signal line 8 is formed so as to be completely contained within the wiring width of the counter electrode 13, so that the wiring width of the source signal line 8 is reduced. The area of the opening can be increased without occupying the opening excessively. Also, the pixel electrode 1
By arranging the first isolated portion 31 on the gate signal line 2, the area of the opening can be further increased, and a liquid crystal display device having a high aperture ratio can be realized. As a result, it is possible to provide a high-brightness liquid crystal display device using a conventional backlight, and it is possible to provide a liquid crystal display device that realizes a conventional brightness with less power consumption.

Further, by forming the counter electrode 13 so as to completely cover the source signal line 8 with the interlayer insulating film 9 ′ interposed therebetween, the electric field formed by the source signal line 8 is shielded by the counter electrode 13. Can be done (shield effect). In particular, since the counter electrode 13 is three-dimensionally arranged between the liquid crystal layer 17 and the source signal line 8, it is possible to more effectively shield the influence of the electric field generated by the source signal line 8 on the liquid crystal layer 17. You can By this,
To prevent disturbance of the electric field formed by the source signal line 8,
Crosstalk can be suppressed by preventing disorder of alignment of liquid crystal molecules.

The driving of the liquid crystal layer 17 by the liquid crystal display device 120 is the same as in the case of the liquid crystal display device 100 according to the first embodiment (FIGS. (A) and (b)). Liquid crystal display device 120
Also in the above, since the picture element electrode 11 is arranged substantially in the center of the two opposing electrodes 13, the electric field E formed in each picture element region is substantially equal on both sides of the picture element electrode 11. Therefore, it is possible to reduce the difference in the viewing angle and the display unevenness in each picture element region, and to realize a liquid crystal display device with higher image quality.

Further, in this embodiment, the counter substrate 122 can be substantially the transparent insulating substrate 12 only by forming the color filter 18 as a part of the interlayer insulating film 9 '. As a result, it is possible to prevent the aperture ratio from being lowered due to the bonding precision of the active matrix substrate 121 and the counter substrate 122, and thus it is possible to further increase the aperture ratio and reduce the cost.

(Embodiment 4) FIG. 9 is a plan view of a reflective liquid crystal display device 130 according to a fourth embodiment of the present invention. 10A shows a cross section of the liquid crystal display device 130 taken along the line AA ′ shown in FIG. 8, and FIG. 10B shows a cross section taken along the line BB ′ shown in FIG. Is shown. FIG.
As shown in (a) and (b), the liquid crystal display device 13
0 is an active matrix substrate 131 and a counter substrate 13
2, and the active matrix substrate 131 and the counter substrate 1
The liquid crystal layer 17 is sandwiched between the liquid crystal layer 17 and the liquid crystal layer 32. In this embodiment, the counter substrate 132 has the substrate 22 whose surface is mirror-finished.

First, the basic structure of the active matrix substrate 131 will be described. As shown in FIGS. 9 and 10A, in the active trix substrate 131, the gate signal line 2 and the gate electrode 2 ′ branched from the gate signal line 2 are provided on the transparent insulating substrate 1 such as glass. The common electrode 15 is formed. A source signal line 8 is formed thereon so as to intersect the gate signal line 2 and the common electrode 15 with the gate insulating film 3 interposed therebetween. A pixel electrode 11 and a counter electrode 13 are formed on top of this with an interlayer insulating film 9 ′ composed of a color filter 18 and an interlayer insulating film 9 interposed therebetween. The pixel electrode 11 and the counter electrode 13 intersect the gate signal line 2 and the common electrode 15 ′, and each counter electrode 13 is formed along the corresponding source signal line 8.

As shown in FIG. 9, the picture element electrodes 11 and the counter electrodes 13 are alternately arranged so that the picture element electrodes 11 and the counter electrodes 13 are substantially equidistant from each other.
In this embodiment, one picture element area (unit display area)
Is a region surrounded by two gate signal lines 2 and two source signal lines 8 (and the counter electrode 13 superimposed on the source signal lines 8), and each pixel region is a picture arranged in the center. The element electrode 11 is included. Two adjacent pixel electrodes 11
A portion 31 (FIG. 10) for separating (vertical direction in FIG. 9)
(A)) is provided on the gate signal line 2. By forming the separation portion 31 in this way, the boundary area of each picture element can be minimized and the aperture ratio can be improved.

At the intersection of the source signal line 8 and the gate signal line 2, a TFT 30 is formed as a switching element so as to correspond to each picture element region. As shown in FIG. 10B, the TFT 30 includes a gate electrode 2 ′ formed on the transparent substrate 1, a gate insulating film 3, a semiconductor layer 4, and a channel protection formed in the central portion of the semiconductor layer 4. It has contact layers 6 a and 6 b formed on both sides of the layer 5 and the channel protection layer 5. The source signal line 8 and the lower transparent conductive film 7a are connected to the contact layer 6a so as to overlap each other. This overlapping portion becomes the source electrode 8a. The drain electrode 8b and the lower transparent conductive film 7b are connected to the contact layer 6b so as to overlap each other.
An interlayer insulating film 9 ′ is formed so as to cover the TFT 30, the gate signal line 2 and the source signal line 8.

The interlayer insulating film 9'of the present embodiment is composed of an insulating film of three colors, which is formed so as to cover each pixel region and becomes the color filter 18, and the interlayer insulating film 9 formed thereon. Consists of. In the color filter 18, the insulating films of three colors are arranged in a predetermined arrangement such as stripe type or delta type. The contact hole 21 of the color filter 18 and the contact hole 10 of the interlayer insulating film 9 are provided at the same position.

As shown in FIGS. 9 and 10A, the transparent conductive film 7b extends along the pixel electrode 11 and overlaps the common electrode 15 via the gate insulating film 3. In the portion where the transparent conductive film 7b faces the common electrode 15, the pixel electrode 11 has the contact hole 1 formed in the interlayer insulating film 9.
0 and the hole 21 provided in the color filter 18
Through it is electrically connected to the transparent conductive film 7b.

Also in this embodiment, as in the case of the first embodiment, as shown in FIG. 3, all the counter electrodes 13 are connected to each other at the portion 13 ′ outside the display area of the insulating substrate 1. And are at the same potential. The counter electrode 13 is connected to the common electrode 15 through the contact hole 10 ′ in the portion 13 ′ outside the display area. In this way, the common electrode 15 and the transparent conductive film 7b having the same potential as the pixel electrode 11 are formed.
And form a storage capacitor.

The method of manufacturing the active matrix substrate 131 according to the present embodiment is the same as that of the active matrix substrate 121 according to the third embodiment, and detailed description thereof will be omitted. The substrate 22 of the counter substrate 132 has a mirror-like surface and serves as a reflection plate. Active matrix substrate 13
1 and the counter substrate 132, the alignment films 16 are formed respectively, and then the substrates 131 and 132 are bonded to each other with a predetermined gap, and a liquid crystal material is injected into the gap to form the liquid crystal layer 1.
7 is formed. In this way, the liquid crystal display device 130 is completed.

According to the liquid crystal display device 130 of the present embodiment, since the source signal line 8 is formed so as to be completely contained within the wiring width of the counter electrode 13, the wiring width of the source signal line 8 is excessively large. The area of the opening can be increased without occupying the area. Further, by disposing the separated portion 31 of the pixel electrode 11 on the gate signal line 2, the area of the opening can be further increased, and a liquid crystal display device having a high aperture ratio can be realized.

Further, by forming the counter electrode 13 so as to completely cover the source signal line 8 with the interlayer insulating film 9 ′ interposed therebetween, the electric field formed by the source signal line 8 is shielded by the counter electrode 13. Can be done (shield effect). In particular, since the counter electrode 13 is three-dimensionally arranged between the liquid crystal layer 17 and the source signal line 8, it is possible to more effectively shield the influence of the electric field generated by the source signal line 8 on the liquid crystal layer 17. You can By this,
To prevent disturbance of the electric field formed by the source signal line 8,
Crosstalk can be suppressed by preventing disorder of alignment of liquid crystal molecules.

The driving of the liquid crystal layer 17 by the liquid crystal display device 130 is the same as in the case of the liquid crystal display device 100 according to the first embodiment (FIGS. (A) and (b)). Liquid crystal display device 130
Also in the above, since the picture element electrode 11 is arranged substantially in the center of the two opposing electrodes 13, the electric field E formed in each picture element region is substantially equal on both sides of the picture element electrode 11. Therefore, it is possible to reduce the difference in the viewing angle and the display unevenness in each picture element region, and to realize a liquid crystal display device with higher image quality.

(Fifth Embodiment) FIG. 11 is a plan view of a liquid crystal display device 140 according to a fifth embodiment of the present invention.
12A shows a cross section of the liquid crystal display device 140 taken along the line BB ′ shown in FIG. 11, and FIG. 12B shows a cross section taken along the line DD ′ shown in FIG. 11. Is shown.
As shown in FIGS. 12A and 12B, the liquid crystal display device 140 includes an active matrix substrate 141, a counter substrate 142, and a liquid crystal layer 17 sandwiched between the active matrix substrate 141 and the counter substrate 142. I have it.

First, the basic structure of the active matrix substrate 141 will be described. As shown in FIGS. 11 and 12A, in the active trix substrate 141, the gate signal line 2, the gate electrode 2 ′ branched from the gate signal line 2, and the gate electrode 2 ′ and The common electrode 15 is formed. A source signal line 8 is formed thereon so as to intersect the gate signal line 2 and the common electrode 15 with the gate insulating film 3 interposed therebetween. A picture element electrode 11 is formed thereon with an interlayer insulating film 9 interposed therebetween. The pixel electrode 11 is the gate signal line 2 and the common electrode 15 '.
Intersects.

In the counter substrate 142, the color filter 14 is formed on the transparent insulating substrate 11 made of glass or the like, and the counter electrode 13 is formed thereon. In this embodiment, the counter electrode 13 is provided not on the active matrix substrate 141 side but on the counter substrate 142 side.

As shown in FIGS. 12A and 12B, the counter electrode 13 is formed along the corresponding source signal line 8 with the liquid crystal layer 17 interposed therebetween. As shown in FIG. 11, the pixel electrodes 11 and the counter electrodes 13 are alternately arranged so that the distances between the pixel electrodes 11 and the counter electrodes 13 are substantially equal when seen in a plan view. ing. In this embodiment, one picture element area (unit display area) is
It is a region surrounded by two gate signal lines 2 and two source signal lines 8 (and the counter electrode 13 overlapping the source signal line 8 via the interlayer insulating film 9), and each pixel region is in the center. It includes a pixel electrode 11 arranged in the. Adjacent 2
A portion 31 for separating one picture element electrode 11 (vertical direction in FIG. 11) is provided on the gate signal line 2. By forming the separation portion 31 in this way, the boundary area of each picture element can be minimized and the aperture ratio can be improved.

TFTs 30 are formed at the intersections of the source signal lines 8 and the gate signal lines 2 as switching elements so as to correspond to the respective picture element regions. As shown in FIG. 12A, the TFT 30 includes a gate electrode 2 ′ formed on the transparent substrate 1, a gate insulating film 3, a semiconductor layer 4, and a channel protection formed in the central portion of the semiconductor layer 4. It has contact layers 6 a and 6 b formed on both sides of the layer 5 and the channel protection layer 5. The source signal line 8 and the lower transparent conductive film 7a are connected to the contact layer 6a so as to overlap each other. This overlapping portion becomes the source electrode 8a. The drain electrode 8b and the lower transparent conductive film 7b are connected to the contact layer 6b so as to overlap each other. T
An interlayer insulating film 9 is formed so as to cover the FT 30, the gate signal line 2, and the source signal line 8.

As shown in FIGS. 11 and 12B, the transparent conductive film 7b extends along the pixel electrode 11 formed on the transparent conductive film 7b and faces the common electrode 15 via the gate insulating film 3. ing. In the portion where the transparent conductive film 7b faces the common electrode 15, the pixel electrode 11 is electrically connected to the transparent conductive film 7b through the contact hole 10 provided in the interlayer insulating film 9.

Also in this embodiment, in the counter substrate 142, all the counter electrodes 13 are connected to each other outside the display area of the insulating substrate 12 and have the same potential. The counter electrode 13 is connected to the common electrode 15 on the active matrix substrate 141 side through a portion outside the display area. In this way, the common electrode 15 and the transparent conductive film 7b having the same potential as the pixel electrode 11 form an auxiliary capacitance.

Next, a method of manufacturing the liquid crystal display device 140 will be described with reference to FIGS. 11, 12A and 12B. First, in the active matrix substrate 141,
The gate signal line 2, the gate electrode 2 ′, and the common electrode 15 are formed on the transparent insulating substrate 1 by patterning a metal layer such as Ta or Al. The thickness of the metal layer is preferably about 3600 to 6500Å. A gate insulating film 3 is formed on the entire insulating substrate 1 so as to cover the gate signal line 2, the gate electrode 2 ′ and the common electrode 15.
The gate insulating film is, for example, S of about 3000 to 5000 Å
iNx, SiO ₂ or the like can be used.

Next, the semiconductor layer 4 is formed on the gate insulating film 3 so as to face the gate electrode 2 '. As the semiconductor layer 4, a-Si, p-Si, or the like can be used. The thickness of the semiconductor layer 4 is preferably about 300 to 500Å. A channel protection layer 5 is patterned on the central portion of the semiconductor layer 4. As the channel protective layer, for example, about 1
A 000Å SiNx layer or the like can be used. next,
Contact layers 6a (source electrode side) and 6b (drain electrode side) made of an n ⁺ -Si layer of about 700 Å are formed so as to overlap with both ends of the channel protection layer 5 and cover the semiconductor layer 4.

A transparent conductive film made of ITO or the like is formed thereon by sputtering, and is patterned to form a transparent conductive film 7a as a lower layer of the source signal line and a lower layer of the source electrode, and a common electrode 1 as a lower layer of the drain electrode.
A transparent conductive film 7b extending toward 5 is formed. A metal layer 8 of Ta, Al or the like is formed thereon by sputtering to a thickness of about 3600 to 6500Å, and is patterned to form the upper layer 8 of the source signal line, the source electrode 8a, and the drain electrode 8b. In this embodiment, as shown in FIG. 12B, the upper metal layer 8
And the lower transparent conductive film 7a form a source signal line 8'having a two-layer structure. In this way, by forming the source signal line 8 ′ in a two-layer structure, even if a part of the upper metal layer 8 is damaged, the source signal line 8 ′ is electrically connected by the lower transparent conductive film 7 a. , Source signal line 8 '
There is an advantage that the disconnection of can be reduced.

Next, an interlayer insulating film 9 is formed by using, for example, a photosensitive acrylic resin so as to cover the TFT 30, the gate signal line 2, the source signal line 3, and the transparent conductive film 7b. In the step of forming the interlayer insulating film 9, the contact hole 10 is simultaneously formed by exposure and alkali development. The thickness of the interlayer insulating film 9 is about 3 μm. The larger the opening area of the contact hole 10, the better. Also,
The interlayer insulating film 9 may be formed using a resin such as polyimide.

Next, a metal layer of Ta, Al, or the like is sputtered on the inter-layer insulating film 9 to a thickness of about 5000 to 700.
The pixel electrode 11 is formed by forming it to a thickness of 0Å and patterning it. The picture element electrode 11 is shown in FIG.
As shown in FIG. 3, the transparent conductive film 7b connected to the drain electrode 8b is electrically connected through the contact hole 10 formed in the interlayer insulating film 9.

On the other hand, in the counter substrate 142, the color filters 14 of red, green and blue are formed by applying a photosensitive color resist on the transparent insulating substrate 12, exposing and developing it. Then, a metal layer of Ta, Al or the like is formed on the color filter 14 by sputtering to have a thickness of about 5000 to 7,000 Å, and is patterned to form the counter electrode 13.

After that, the active matrix substrate 141
The alignment film 16 is formed on each of the and the opposite substrate 142. Then, the two substrates 141 and 142 are attached to each other with a predetermined gap therebetween, and a liquid crystal material is injected into the gap to form the liquid crystal layer 17. In this way, the liquid crystal display device 1
40 is completed.

In this embodiment, the picture element electrodes 11 and the counter electrodes 13 are alternately arranged in the same direction.
The counter electrode 13 and the counter electrode 13 are arranged so as to be substantially equally spaced. Further, the counter electrode 13 is formed so as to face all the source signal lines 8 in the display screen with the liquid crystal layer 17 interposed therebetween, and the width of the counter electrode 13 is made wider than the width of the source signal line 8. , And so as to completely cover the source signal line 8.

As described above, since the source signal line 8 is formed so as to completely fit within the wiring width of the counter electrode 13,
It is possible to increase the area of the opening without the wiring width of the source signal line 8 occupying the opening excessively. Furthermore,
Counter substrate 1 having counter electrode 13 and color filter 14
By forming it on the 42 side, the counter electrode 13 can also serve as a black matrix. As described above, by increasing the aperture ratio, the area through which the backlight light is transmitted is increased, so that it is possible to provide a high-brightness liquid crystal display device using a conventional backlight. Further, it is possible to provide a liquid crystal display device that realizes the conventional brightness with less power consumption.

Further, in the present embodiment, the counter electrode 13
Is formed on the side of the counter substrate 142 having the color filter 14, the parasitic capacitance can be reduced as compared with the case where the counter electrode 13 is formed on the side of the active matrix substrate 141.

The pixel electrode 11 is composed of two counter electrodes 13
Since they are arranged almost in the center, the electric field formed in each picture element region is substantially equal on both sides of the picture element electrode 11. Therefore, it is possible to reduce the difference in the viewing angle and the display unevenness in each picture element region, and to realize a high-quality display.

In the first to fifth embodiments described above, the counter electrode 13 is formed in a stripe shape, but the counter electrode 1
The shape of 3 is not limited to this. In any of the embodiments, for example, a comb-shaped counter electrode as shown in FIG. 13 can be used. If the counter electrode 13 is formed so as to satisfy the arrangement relationship with the source signal line 8 described in each embodiment, the effect of the present invention can be obtained.

Also, the arrangement described in the second embodiment, in which each pixel region includes two or more picture element electrodes 11 and each picture element electrode 11 is sandwiched by the counter electrodes 13, is also used in the third to third embodiments. 5
It can be applied to the case of. The combination of the arrangement of the picture element electrode 11 and the counter electrode 13 in each picture element region and the color filter 14 or 18 is effective for both the transmissive and reflective liquid crystal display devices.

Those skilled in the art will find these facts in Example 1 above.
It can be understood by the description of 5

[0113]

As described above, according to the present invention, the pixel electrode and the counter electrode are formed at substantially equal intervals, so that the pixel electrode is arranged substantially at the center of the two counter electrodes. . As a result, the electric field formed in each pixel region becomes substantially equal on both sides of the pixel electrode, the difference in viewing angle and display unevenness in each pixel region are reduced, and high quality display is realized. be able to.

By arranging a plurality of picture element electrodes and corresponding common electrodes in one picture element region, the pitch between the electrodes can be reduced and display can be performed with a lower driving voltage.

Further, according to the present invention, the counter electrode is formed along the source signal line, and the source signal line is arranged so as to be completely within the wiring width of the counter electrode. It is possible to increase the area of the opening without occupying the opening with an extra width. Also, by arranging the separated portion of the pixel electrode on the gate signal line,
Further, the aperture ratio can be improved. As a result, the area of the opening through which the backlight light is transmitted can be increased, so that it is possible to provide a high-brightness liquid crystal display device using a conventional backlight, and realize the conventional brightness with less power consumption. A liquid crystal display device can be provided.

Further, as described above, by forming the counter electrode so as to completely cover the source signal line with the interlayer insulating film interposed therebetween, the electric field formed by the source signal line can be shielded by the counter electrode. Can (shield effect). Particularly, when the counter electrode is three-dimensionally arranged between the liquid crystal layer and the source signal line, the influence of the electric field generated by the source signal line on the liquid crystal layer can be shielded more effectively. As a result, the disturbance of the electric field formed by the source signal line can be prevented, the disturbance of the alignment of the liquid crystal molecules can be prevented, and the crosstalk can be suppressed, so that a higher quality liquid crystal display device can be provided.

Further, when the counter electrode is formed on the counter substrate side with the liquid crystal layer interposed therebetween, the parasitic capacitance can be reduced, and when the counter substrate is provided with a color filter, the counter electrode can be reduced. Can double as a black matrix.

Further, when the color filter is formed on the active matrix substrate side, the requirement for the bonding accuracy is not so strict as compared with the case where the color filter is formed on the counter substrate. Therefore, the aperture ratio caused by the bonding accuracy is increased. Can be prevented from decreasing.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of a liquid crystal display device according to an embodiment of the present invention.

2A and 2B are cross-sectional views taken along lines AA 'and BB' of the liquid crystal display device shown in FIG. 1, respectively.

FIG. 3 is a schematic view of an active matrix substrate of a liquid crystal display device according to one embodiment of the present invention.

FIG. 4A and FIG. 4B are views showing how liquid crystal is driven by a liquid crystal display device according to an embodiment of the present invention.

FIG. 5 is a plan view showing a configuration of a liquid crystal display device according to another embodiment of the present invention.

6A and 6B are cross-sectional views taken along lines CC ′ and DD ′ of the liquid crystal display device shown in FIG. 5, respectively.

FIG. 7 is a plan view showing a configuration of a liquid crystal display device according to still another embodiment of the present invention.

8A and 8B are cross-sectional views taken along lines AA 'and BB' of the liquid crystal display device shown in FIG. 7, respectively.

FIG. 9 is a plan view showing the structure of a liquid crystal display device according to another embodiment of the present invention.

10A and 10B are cross-sectional views taken along lines AA 'and BB' of the liquid crystal display device shown in FIG. 9, respectively.

FIG. 11 is a plan view showing a configuration of a liquid crystal display device according to still another embodiment of the present invention.

12A and 12B are views showing cross sections taken along lines BB ′ and DD ′ of the liquid crystal display device shown in FIG. 11, respectively.

FIG. 13 is a diagram showing another shape of the common electrode.

14A and 14B are diagrams showing a planar configuration of a conventional liquid crystal display device.

15 is a line A of the conventional liquid crystal display device shown in FIG.
It is a figure which shows the cross section along -A '.

[Explanation of symbols]

 1 Transparent Insulating Substrate 2 Gate Signal Line 2'Gate Electrode 3 Gate Insulating Film 4 Semiconductor Layer 5 Channel Protecting Layer 6a, 6b Contact Layers 7a, 7b Transparent Conductive Film 8 Source Signal Line Upper Metal Layer 8a Source Electrode 8b Drain Electrode 9 Interlayer insulating film 10 Contact hole 11 Picture element electrode 12 Transparent insulating substrate 13 Counter electrode 14 Color filter 15 Common electrode 16 Alignment film 17 Liquid crystal layer 30 TFT 31 Separation part between picture element electrodes 100 Liquid crystal display device 101 Active matrix substrate 102 Facing substrate

Claims (17)

[Claims] 1. An insulating substrate, a plurality of switching elements arranged in a matrix on the insulating substrate, a first signal wiring for applying a signal for controlling the switching element to the switching element, and A second signal wiring which is arranged so as to intersect with the first wiring and applies a data signal to the switching element; and a contact hole which is formed so as to cover the switching element and the first and second signal wirings. An active matrix including an interlayer insulating film, a pixel electrode formed on the interlayer insulating film and electrically connected to the switching element through the contact hole, and a counter electrode formed on the interlayer insulating film. A substrate, wherein the counter electrode is arranged along the second signal wiring so as to face the second signal wiring with the interlayer insulating film interposed therebetween. The electrodes are arranged along the same direction as the counter electrode, and the picture element electrodes and the counter electrodes are alternately arranged so that the picture element electrodes and the counter electrodes are substantially equidistant. , Active matrix substrate. 2. The picture element region corresponding to each switching element includes at least one picture element electrode, and each picture element electrode is sandwiched by two counter electrodes. Active matrix substrate. 3. The adjacent pixel region according to claim 1, wherein a boundary between two pixel electrodes adjacent to each other in the direction is formed on the first signal line. The active matrix substrate described. 4. The width of the counter electrode is wider than the width of the second signal wiring, and the wiring width of the counter electrode is formed so as to completely cover the second signal wiring. 1 to
3. The active matrix substrate according to any one of 3 above. 5. The active matrix substrate according to claim 1, wherein the counter electrode is formed on all the second signal wirings via the interlayer insulating film. 6. The active matrix substrate according to claim 5, further comprising a counter electrode disposed between the pixel electrodes, in addition to the second signal line. 7. The active matrix substrate according to claim 1, wherein the counter electrodes are connected to each other outside the display region and have the same electric potential. 8. A common electrode is arranged so as to intersect with the pixel electrode and forms an auxiliary capacitance between the pixel electrode and the pixel electrode, and the counter electrode is electrically connected to the common electrode. The active matrix substrate according to claim 7, which is connected. 9. The interlayer insulating film includes a first insulating layer made of an insulating film of three colors forming a color filter, and a second insulating layer formed so as to cover the first insulating layer. An active matrix substrate according to any one of claims 1 to 8 including. 10. The active matrix substrate according to claim 9, wherein the color filter is formed by patterning a film-shaped resin having photosensitivity of three colors. 11. The pixel electrode is electrically connected to the switching element through a first contact hole formed in the first insulating layer and a second contact hole formed in the second insulating layer. 10. The connection according to claim 9,
11. The active matrix substrate according to any one of items 10 and 10. 12. The first contact hole is formed so that its width is smaller than the width of the common electrode and completely overlaps with it, and the second contact hole has a width of the first contact hole. The method according to claim 11, wherein the width is smaller than the width of the hole and is formed inside the first contact hole.
The active matrix substrate according to. 13. A liquid crystal display device comprising: the active matrix substrate according to claim 1; a counter substrate; and a liquid crystal layer sandwiched between the active matrix substrate and the counter substrate. 14. An active matrix substrate according to claim 9, an opposite substrate having a transparent insulating substrate, and a liquid crystal layer sandwiched between the active matrix substrate and the opposite substrate. Liquid crystal display device equipped. 15. The active matrix substrate according to claim 1, a counter substrate having a mirror-like reflective surface, and a liquid crystal layer sandwiched between the active matrix substrate and the counter substrate. A reflection type liquid crystal display device including. 16. A first insulating substrate, a plurality of switching elements arranged in a matrix on the insulating substrate, and a first signal wiring for giving a signal for controlling the switching element to the switching element. A second signal wiring that is arranged so as to intersect with the first wiring and applies a data signal to the switching element, and a contact that is formed so as to cover the switching element and the first and second signal wirings. An active matrix substrate having: an insulating film having holes; a pixel electrode formed on the insulating film and electrically connected to the switching element through the contact hole; a second insulating substrate; A counter substrate having a counter electrode formed on a second insulating substrate; and a liquid crystal layer sandwiched between the active matrix substrate and the counter substrate. In the liquid crystal display device, the counter electrode is arranged along the second signal line with the liquid crystal layer sandwiched therebetween and so as to face the second signal line. A liquid crystal display device, wherein the liquid crystal display device is arranged along the same direction as the counter electrode, and the pixel electrodes and the counter electrode are alternately arranged at substantially equal intervals. 17. The counter substrate has a color filter formed on the second insulating substrate.
3. The liquid crystal display device according to 1.