JP2002323704A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a pixel electrode from being affected by a electric field from a signal line, and to increase an aperture ratio. SOLUTION: A light transmitting pixel electrode PX, a light reflection film disposed at the lower layer thereof via a first insulating film consisting of an organic material and a thin film transistor TFT disposed at the lower layer of the light reflection film via a second insulating film having at least an organic material layer are provided in each pixel area of the surface on a liquid crystal LC side of one substrate of substrates SUB disposed opposite to each other via the liquid crystal LC. The light reflection film is formed to be commonly connected to the reflection films of other adjacent pixel areas and the pixel electrode is electrically connected to the thin film transistor by a contact hole CH formed by penetrating the first and the second insulating films through the aperture part of the reflection film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device of a reflection type or a transflective type.

[0002]

2. Description of the Related Art A liquid crystal display device called a reflection type or a transflective type uses external light such as the sun constantly or temporarily, and has a low power consumption effect.

There is known a liquid crystal display device of the so-called active matrix type in which the reflection type or the transflective type is applied.

Here, the active matrix type liquid crystal display means that, for example, one of the substrates opposed to each other with the liquid crystal interposed therebetween extends on the liquid crystal side surface of the substrate and extends in the x direction and the y direction, for example. X extending in the y direction with the gate signal line
Drain signal lines arranged in parallel in the direction are formed, and a region surrounded by each of the signal lines is a pixel region.

In each of these pixel regions, a thin film transistor activated by a scanning signal from one gate signal line and a pixel electrode to which a video signal from one drain signal line is supplied via the thin film transistor are formed. ing.

The pixel electrode generates an electric field between the pixel electrode and the counter electrode, and the electric field controls the light transmittance of the liquid crystal.

When a liquid crystal display device of this type is, for example, of a reflection type, it is necessary to form a reflection film in addition to the above structure. This is to form an optical path for irradiating extraneous light from one of the substrate sides by the reflection film and irradiating the substrate side again through the liquid crystal.

[0008]

However, it is pointed out that, for example, when a reflection type liquid crystal display device is constructed in this manner, for example, an electric field from a drain signal line affects a pixel electrode and image quality is deteriorated. Was done.

In the case of the reflection type, for example, the amount of light that can be seen by the observer is smaller than that in the case of the transmission type, and an improvement in the aperture ratio has been desired.

It has also been pointed out that it is not sufficient to avoid external light irradiation on the thin film transistor, and that the characteristics of the thin film transistor are not stabilized.

Further, there has been a demand for reducing the misalignment of each of the transparent substrates disposed to face each other with the liquid crystal interposed therebetween, and reducing the misalignment.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a liquid crystal display device in which the influence of an electric field from a signal line on a pixel electrode is prevented.

It is another object of the present invention to provide a liquid crystal display device having an improved aperture ratio.

Another object of the present invention is to provide a liquid crystal display device in which the characteristics of the thin film transistor are stabilized.

Still another object of the present invention is to provide a liquid crystal display device which has a margin for alignment of the substrates arranged to face each other with a liquid crystal interposed therebetween.

[0016]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

Means 1. The liquid crystal display device according to the present invention includes, for example, a light-transmitting pixel electrode in each pixel region on a liquid crystal side surface of one of the substrates disposed to face each other with a liquid crystal therebetween, and a lower layer made of an organic material. A light reflecting film disposed via a first insulating film; and a thin film transistor disposed via a second insulating film having at least an organic material layer below the light reflecting film; Is formed so as to be commonly connected to a light reflection film of another adjacent pixel region, and the pixel electrode is formed to penetrate the first insulation film and the second insulation film through an opening of the reflection film. The thin film transistor is electrically connected to the thin film transistor by a contact hole.

Means 2. The liquid crystal display device according to the present invention includes, for example, a light-transmitting pixel electrode in each pixel region on a liquid crystal side surface of one of the substrates disposed to face each other with a liquid crystal therebetween, and a lower layer made of an organic material. A conductive film disposed via a first insulating film; and a thin film transistor disposed via a second insulating film having at least an organic material layer below the conductive film, wherein the conductive film is transparent. Having a light reflection portion scatteredly formed in the region of the conductive film, formed in common with a conductive film of another adjacent pixel region, and the pixel electrode is formed through an opening of the conductive film. The thin film transistor is electrically connected to the thin film transistor through a contact hole formed through the first insulating film and the second insulating film.

Means 3. The liquid crystal display device according to the present invention includes, for example, a pixel electrode serving also as a reflective film in each pixel region on a liquid crystal side surface of one of the substrates disposed to face each other with a liquid crystal therebetween, and a lower layer made of an organic material. A conductive film disposed via a first insulating film; and a thin film transistor disposed via a second insulating film having at least an organic material layer below the conductive film, wherein the conductive film is adjacent to the conductive film. Formed in common with the conductive film of the other pixel region, and
The pixel electrode is electrically connected to the thin film transistor through a contact hole formed in the first insulating film and the second insulating film through an opening of the conductive film.

Means 4 The liquid crystal display device according to the present invention includes, for example, a pixel electrode in each pixel region on a liquid crystal side surface of one of the substrates opposed to each other with the liquid crystal interposed therebetween, and a first insulating film made of an organic material below the pixel electrode. And a thin film transistor disposed via a second insulating film having at least an organic material layer below the conductive film, and the conductive film is disposed adjacent to another pixel region. The pixel electrodes are formed in common with the conductive film, and the pixel electrodes are formed in a light-reflecting portion or a reflective film region formed in a light-transmitting region. It is formed having a light transmitting portion, and is electrically connected to the thin film transistor through a contact hole formed in the first insulating film and the second insulating film through an opening of the conductive film. It is.

Means 5. The liquid crystal display device according to the present invention includes, for example, a pixel electrode serving also as a reflective film in each pixel region on a liquid crystal side surface of one of the substrates disposed to face each other with a liquid crystal therebetween, and a lower layer made of an organic material. A light-transmitting conductive film disposed via a first insulating film; and a thin film transistor disposed via a second insulating film having at least an organic material layer below the conductive film; The conductive film is formed so as to be commonly connected to a conductive film of another adjacent pixel region, and is formed so as to cover the thin film transistor. The pixel electrode is formed through an opening of the conductive film. The thin film transistor is electrically connected to the thin film transistor through a contact hole formed through the first insulating film and the second insulating film.

Means 6. The liquid crystal display device according to the present invention includes, for example, a pixel electrode in each pixel region on a liquid crystal side surface of one of the substrates opposed to each other with the liquid crystal interposed therebetween, and a first insulating film made of an organic material below the pixel electrode. And a thin film transistor arranged via a second insulating film having at least an organic material layer below the conductive film, wherein the conductive film is adjacent to the conductive film. The pixel electrodes are formed so as to be commonly connected to the conductive films of other pixel regions, and are formed so as to cover the thin film transistors. Formed in a region of a light reflecting portion or a reflective film to be diffused, and penetrating the first insulating film and the second insulating film through an opening of the conductive film. Contact hole And it is characterized in that it is connected the TFT electrically.

Means 7 The liquid crystal display device according to the present invention is, for example, arranged in each pixel region on a liquid crystal side surface of one of the substrates disposed to face each other with the liquid crystal interposed therebetween, in a direction extending in one direction and juxtaposed in a direction intersecting the direction. A pixel electrode composed of a group of electrodes to be formed, a counter electrode composed of a non-light-transmitting conductive film disposed under the first insulating film composed of an organic material, and at least an organic material layer disposed under the counter electrode And a thin film transistor disposed via a second insulating film having the same. The counter electrode is formed so as to be commonly connected to a counter electrode of another adjacent pixel region, and covers the thin film transistor. And the pixel electrode is electrically connected to the thin film transistor through a contact hole formed through the first insulating film and the second insulating film through an opening of the counter electrode. And it is characterized in that it is connected.

Means 8. According to the liquid crystal display device according to the present invention, for example, one of the substrates opposed to each other with the liquid crystal interposed therebetween is extended in one direction in each pixel region on the liquid crystal side surface in a direction intersecting the direction. A pixel electrode composed of a group of electrodes arranged in parallel, a counter electrode composed of a conductive film disposed under the first insulating film composed of an organic material below the pixel electrode, and at least an organic material layer disposed under the counter electrode; And a thin film transistor disposed via a second insulating film, wherein the counter electrode is formed so as to be commonly connected to a counter electrode of another adjacent pixel region, and formed so as to cover the thin film transistor. In addition, the counter electrode has a light reflecting portion formed scatteredly in the region of the light-transmitting film or a light transmitting portion formed scatteredly in the region of the reflective film. Formed and the image Electrode, the first insulating film through the opening of the counter electrode and the second
The thin film transistor is electrically connected to the thin film transistor by a contact hole formed through the insulating film.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the liquid crystal display device according to the present invention will be described below with reference to the drawings.

Embodiment 1 FIG. << Overall Configuration >> FIG. 2 is a plan view showing the entire liquid crystal display device according to the present invention.

There are a pair of transparent substrates SUB1 and SUB2 which are arranged to face each other via a liquid crystal, and the liquid crystal is sealed by a sealing material SL which also serves to fix one transparent substrate SUB1 to the other transparent substrate SUB2.

On the liquid crystal side surface of the one transparent substrate SUB1 surrounded by the sealing material SL, a gate signal line GL extending in the x direction and juxtaposed in the y direction and y extending in the y direction. And drain signal lines DL arranged side by side in the direction.

Each gate signal line GL and each drain signal line D
L constitute a pixel region, and a matrix-like aggregate of these pixel regions is a liquid crystal display unit A.
R.

In each pixel area, as shown in a circle in the figure, a thin film transistor TFT activated by a scanning signal from a gate signal line GL, and an image from a drain signal line DL via the thin film transistor TFT. A pixel electrode PX to which a signal is supplied is formed.

This pixel electrode PX is connected to the other transparent substrate SU.
An electric field is generated between the electrode and a counter electrode (not shown) formed on the B2 side, and the light transmittance of the liquid crystal is controlled by the electric field.

One end of each of the gate signal lines GL extends beyond the sealing material SL, and the extending end forms a terminal to which an output terminal of the vertical scanning drive circuit V is connected. . The input terminal of the vertical scanning drive circuit V is adapted to receive a signal from a printed circuit board arranged outside the liquid crystal display device.

The vertical scanning drive circuit V includes a plurality of semiconductor devices, and a plurality of gate signal lines GL adjacent to each other are grouped, and one semiconductor device is assigned to each group. .

Similarly, one end of each of the drain signal lines DL extends beyond the sealing material SL, and the extending end forms a terminal to which an output terminal of the video signal driving circuit He is connected. Has become. The input terminal of the video signal drive circuit He is adapted to receive a signal from a printed circuit board arranged outside the liquid crystal display device.

The video signal driving circuit He also includes a plurality of semiconductor devices, and a plurality of drain signal lines DL adjacent to each other are grouped, and one video signal driving circuit He is assigned to each of these groups. It has become.

Each of the gate signal lines GL is sequentially selected by a vertical scanning circuit V according to a scanning signal.

Each drain signal line DL supplies a video signal to each drain signal line DL in accordance with the selection timing of the gate signal line GL by a video signal drive circuit.

In this embodiment, the vertical scanning circuit V and the video signal driving circuit He are semiconductor devices (chips) directly mounted on the transparent substrate SUB1, but are not limited to this. Semiconductor devices formed by a so-called film carrier method may be used, and these circuits may be configured to be externally attached to the transparent substrate SUB1. Alternatively, the transparent substrate SUB1
It may be formed on top. << Configuration of Pixel >> FIG. 1 is a plan view of the pixel area (the area shown in a circle in FIG. 2). Also,
A cross section taken along line III-III in FIG. 1 is shown in FIG. 3, and a cross section taken along line IV-IV is shown in FIG.

First, a gate signal line GL extending in the x direction and juxtaposed in the y direction is formed on the surface of the transparent substrate SUB1.

The transparent substrate S on which the gate signal lines GL are formed
An insulating film GI is formed on the surface of UB1 so as to cover the gate signal line GL.

The insulating film GI functions as an interlayer insulating film with the gate signal line GL in a later-described drain signal line DL forming region, and functions as a gate insulating film in a later-described thin film transistor TFT forming region. In a region where a capacitor Cadd described later is formed, the capacitor Cadd has a function as a dielectric film.

The region where the thin film transistor TFT is formed on the surface of the insulating film GI is, for example, amorphous S
A semiconductor layer AS made of i is formed.

By forming a drain electrode SD1 and a source electrode SD2 on the upper surface of the semiconductor layer AS, an MIS transistor having an inverted staggered structure using a part of the gate signal line GL as a gate electrode is formed. It has become.

Here, the drain electrode SD1 and the source electrode SD2 are formed simultaneously with the formation of the drain signal line DL.

That is, a drain signal line DL extending in the y direction and juxtaposed in the x direction is formed on the surface of the insulating film GI, and a part thereof extends to the surface of the semiconductor layer AS. This forms the drain electrode SD1. The source electrode SD2 is separated from the drain electrode SD1 by a distance corresponding to the channel length of the thin film transistor TFT on the surface of the semiconductor layer AS.
Are formed.

This source electrode SD2 is connected to a pixel electrode P described later.
The contact portion is formed by extending the source electrode SD2 from the surface of the semiconductor layer AS to the pixel region side.

In this case, the extending portion of the source electrode SD2 extends beyond the contact portion and the thin film transistor TFT
Is formed so as to reach a formation region of another gate signal line GL adjacent to a gate signal line GL for driving the gate signal line GL, and is formed so as to overlap a part of the gate signal line GL.

That is, by doing so, a capacitive element Cadd using the insulating film GI as a dielectric film is formed between the pixel electrode PX and the gate signal line GL superimposed on the pixel electrode PX. For example, a video signal supplied to the pixel electrode PX can be stored for a relatively long time.

At the interface between the drain electrode SD1 and the source electrode SD2 on the surface of the semiconductor layer AS, a contact layer d0 in which the surface of the semiconductor layer AS is doped with a high concentration of impurities is formed.

The contact layer d0 is formed, for example, by doping the surface of the semiconductor layer AS with a high concentration impurity.
The drain electrode SD1 and the source electrode SD2 are patterned, and the drain electrode SD1 and the source electrode SD2 are used as a mask, and the impurity layer exposed from the mask is etched. Of course, it may be formed by directly doping a necessary region.

On the surface of the transparent substrate SUB1 on which the thin film transistor TFT is formed as described above, a protective film PSV made of, for example, SiN covers the thin film transistor TFT.
1 is formed.

This protective film PSV1 is formed in order to avoid direct contact between the thin film transistor TFT and a liquid crystal LC, which will be described later, and to prevent deterioration in characteristics of the thin film transistor TFT. In some cases, the protective film PSV1 can be omitted. In particular, a channel stopper type TFT has SiN in a stopper portion, and p-Si can be omitted because TFT characteristics are more stable than a-Si. In this embodiment, the protection films PSV2 and PV, which will be described later, are further formed on the protection film PSV1.
The function of the protective film is strengthened together with the SV3, and the material of the protective films PSV2 and PSV3 is made of, for example, an organic material such as a resin, thereby preventing the dielectric constant of the entire protective film from increasing.

The protective film PSV2 is formed on the protective film PSV1, and a reflective film RL made of a metal such as Al is formed on the surface thereof. This reflection film RL reflects external light from the transparent substrate SUB2 side. The reflection film is formed so as to overlap the gate signal line GL and the drain signal line DL and to extend to other adjacent pixel regions. This is because the aperture ratio can be significantly improved as compared with the case where the pixel regions are formed independently for each pixel region.

The reflective film RL is provided with an opening at least in a portion overlapping with a contact portion for connecting to a pixel electrode PX of the source electrode SD2 of the thin film transistor TFT described later. The opening of the reflection film RL is designed to connect the pixel electrode PX and the source electrode SD2 of the thin film transistor TFT through this portion.

A protective film PSV3 made of, for example, a resin is formed on the surface of the protective film PSV2 on which the reflective film RL is formed as described above so as to cover the protective film PSV2.

The protective film PSV3 is formed by contacting the protective film PSV2 and the protective film PSV1 under the protective film PSV3 in order to expose a part of the contact portion of the source electrode SD2 of the thin film transistor TFT. Hole CH is formed.

A translucent pixel electrode PX made of, for example, an ITO (Indium Tin Oxide) film is formed on the upper surface of the protective film PSV3. This pixel electrode PX is formed electrically independently for each pixel, and its periphery is positioned close to the gate signal line GL side and the drain signal line DL side to improve the aperture ratio.

It is sufficient that PX between pixels is separated from each other.
The boundary is the drain signal line DL or the gate signal line G
It may be positioned on L or another location. This is because the influence from the drain signal line DL and the gate signal line GL is shielded by the reflection film RL, so that the influence on the drain signal line DL and the gate signal line GL due to the boundary position of PX is eliminated.

Further, by the formation of the pixel electrode PX,
The contact hole C formed in the formation region
H through the source electrode S of the thin film transistor TFT
D2 is electrically connected.

Although the pixel electrode PX is formed of an ITO film as a material, it goes without saying that the pixel electrode PX may be formed of a non-translucent material such as metal. In this case, it is preferable to use a metal having a high reflectance, such as Al, for example.

In this case, the pixel electrode PX has a function as a reflection film for reflecting external light from the transparent substrate SUB2.

Then, an alignment film ORI1 is formed on the surface of the transparent substrate SUB1 on which the pixel electrode PX is formed so as to cover the pixel electrode PX. This alignment film OR
I1 is a film that is in direct contact with the liquid crystal LC and determines the initial alignment direction of the molecules of the liquid crystal.

The transparent substrate SUB2 is disposed on the transparent substrate SUB1 thus formed via the liquid crystal LC.

The structure is such that the black matrix BM is not formed on the liquid crystal side surface of the transparent substrate SUB2. The black matrix BM is usually formed so as to cover the thin film transistor TFT and to define each adjacent pixel region. These functions are performed by the reflection formed on the transparent substrate SUB1 side. Membrane RL
Is configured to fulfill.

By not forming the black matrix BM, it is possible to increase the tolerance of misalignment between the transparent substrate SUB1 and the transparent substrate SUB2 in the opposed arrangement.

For this reason, a color filter FIL is first formed on the liquid crystal side surface of the transparent substrate SUB2. This color filter FIL has red (R), green (G),
It consists of three colors of blue (B), each of which is y
Are formed in common in the respective pixel regions arranged side by side in the direction, and are arranged in the x direction in the order of, for example, R, G, B, R, G,....

Then, on the surface of the transparent substrate SUB2, a flattening film OC is formed so as to cover these color filters FIL. This flattening film is made of, for example, a resin film, so that a step due to the color filter FIL is not made obvious.

On the surface of the flattening film OC, for example, a counter electrode CT formed of, for example, each pixel ITO film is formed in common for each pixel region.

On the surface of the counter electrode CT, an alignment film ORI2 is formed over almost the entire area. This alignment film ORI2 is a film that directly contacts the liquid crystal LC and determines the initial alignment direction of the liquid crystal molecules.

In the liquid crystal display device configured as described above, when a video signal is supplied to the pixel electrode PX in response to the reference signal applied to the counter electrode CT, the light transmission of the liquid crystal LC is caused by a voltage between the pixels. Control the rate.

Then, extraneous light incident from the transparent substrate SUB2 side passes through the liquid crystal whose light transmittance is controlled, is reflected by the reflection film RL, passes through the liquid crystal, and passes through the transparent substrate SUB2. It will be visible to the observer.

In the liquid crystal display device configured as described above, since the reflection film RL covers the drain signal line DL and the gate signal line GL, the liquid crystal display device is connected to the drain signal line DL or the gate signal line GL. Can be prevented from being terminated at the pixel electrode PX.

That is, the lines of electric force from the drain signal line DL or the gate signal line GL are terminated at the reflection film RL and can be prevented from reaching the pixel electrode PX.

For this reason, it is preferable to apply an appropriate potential to the reflective film RL for achieving this effect. For example, a circuit is complicated by supplying a reference signal supplied to the counter electrode CT. Can not be.

For the same reason, the thin film transistor T
Since the FT is also covered by the reflection film RL, the characteristics of the thin film transistor TFT can be stabilized.

In the configuration described above, the line width of the drain signal line DL or the gate signal line GL can be increased without being affected by the aperture ratio of the pixel.
For this reason, it is possible to avoid adverse effects due to distortion of the waveform of the video signal supplied to the drain signal line DL or the scanning signal supplied to the gate signal line GL.

In the above-described embodiment, the pixel electrode PX is formed of a translucent material as an example. In such a configuration, the color filter FIL is provided on the transparent substrate SUB1. You may. For example, instead of forming the protective film PSV3 shown in the figure, a color filter FIL can be formed in this portion.

Embodiment 2 FIG. FIG. 5 is a plan view showing another embodiment of the liquid crystal display device according to the present invention, and corresponds to FIG.

The difference from FIG. 1 resides in that the capacitance element Cstg having the pixel electrode PX as one electrode and the other electrode being a capacitance signal line CL different from the gate signal line GL. FIG. 6 shows an equivalent circuit thereof.

In FIG. 5, the capacitance signal line CL is formed substantially at the center of the pixel region in parallel with the gate signal line GL. This capacitance signal line CL is, for example, a gate signal line GL.
Are formed at the same time as the gate signal line GL, and are formed of the same layer and the same material as the gate signal line GL.

The source electrode SD2 of the thin film transistor TFT extends on the insulating film GI, and is formed such that its extending end overlaps the capacitance signal line CL.

As a result, a capacitive element Cstg using the insulating film GI as a dielectric film is formed at the overlapping portion of the capacitive signal line CL and the source electrode SD2 of the thin film transistor TFT.

Incidentally, for example, the same signal as the reference voltage signal supplied to the counter electrode CT is supplied to the capacitance signal line CL, so that the potential is stabilized.

Further, the capacitance signal line CL is connected to the reflection film RL and the contact hole CH (sequential through holes of the protection films PSV2, PSV1, and the insulating film GI). Has been

In FIG. 5, a cross-sectional view taken along the line III-III and a cross-sectional view taken along the line IV-IV are the same as FIGS. 3 and 4, respectively.

Embodiment 3 FIG. In each of the embodiments described above, the reflective film RL is made of, for example, Al and formed over the entire pixel region. However, this reflective film portion may be configured as shown in FIG.

FIGS. 7A and 7B are diagrams showing a portion corresponding to the reflection film RL, wherein FIG. 7A is a plan view and FIG. 7B is a cross-sectional view taken along the line bb of FIG.

In FIG. 7, a film corresponding to the reflection film RL has a two-layer structure, the first layer of which is a light-transmitting film 10 such as an ITO film, and the second layer of which a dot-like pattern is scattered. It may be formed of the non-light-transmitting metal film 11 made of, for example, Al.

With such a configuration, a so-called partial transmission type liquid crystal display device can be configured.

That is, in the portion where the metal film 11 is formed, the external light from the transparent substrate SUB2 is reflected, and the light transmitting film 10 on which the metal film 11 is not formed is reflected.
Is formed so that extraneous light from the backlight is transmitted from the transparent substrate SUB1 side in the portion where is formed.

For the same purpose, as shown in FIG. 8 (corresponding to FIG. 7), the first layer is made of a non-light-transmitting metal film 11, for example, made of Al, in which dot-like patterns are scattered. Needless to say, the layer may be formed of a light-transmitting film 10 such as an ITO film formed over the entire pixel region.

On the other hand, on the contrary, ITO is formed in the non-translucent metal film.
It goes without saying that a light-transmitting film such as a film may be formed, and at least the metal film may be partially removed at least at the portion.

Embodiment 4 FIG. FIG. 9 is a plan view showing another embodiment of the liquid crystal display device according to the present invention, and corresponds to FIG. FIG. 1 is a cross-sectional view taken along line XX of FIG.
FIG. 11 shows a cross section taken along line XI-XI of FIG.

9 differs from FIG. 1 in that the layer formed as the reflection film RL is a light-transmitting film such as an ITO film. Although this film can lose its function as a reflection film, for example, by supplying the same signal as the reference voltage signal supplied to the counter electrode CT, it is possible to avoid unstable characteristics due to the electric field of the thin film transistor TFT.

Next, the pixel electrode PX is connected to, for example, A
The pixel electrode PX is made of a non-translucent metal such as
Has a function as a reflective film.

The pixel electrode PX is electrically independent from the pixel electrode PX of another adjacent pixel region by being physically separated. In this embodiment, one gate signal line GL is covered. It is formed like this.

That is, the pixel electrode PX is adjacent to one of the sides on the side of the gate signal line GL (in this embodiment, the side on the side of the gate signal line GL on which the thin film transistor TFT of the pixel region overlaps). It is formed over the pixel area.

In this manner, the thin film transistor TFT has a configuration in which the thin film transistor TFT is covered by the pixel electrode PX, and physical separation from the pixel electrode PX of another adjacent pixel region is performed in the vicinity of the thin film transistor TFT. It has become so.

Therefore, the thin film transistor TFT can block the irradiation of light from the transparent substrate SUB2 side by the pixel electrode PX, and can prevent the deterioration of the characteristics.

Embodiment 5 FIG. FIG. 12 shows that the capacitance element Cstg is replaced with the capacitance element line C in the configuration shown in the sixth embodiment.
This is provided between L and the pixel electrode PX.

Even in such a configuration, the pixel electrode PX
Is made of a non-translucent metal such as Al,
The pixel electrode PX has a function as a reflection film and is formed so as to cover one gate signal line GL.

As a result, similarly to the sixth embodiment, the thin film transistor TFT can be protected from an electric field and external light.

The sectional view taken along the line XX and the sectional view taken along the line XI-XI in FIG.
0 and FIG.

Embodiment 6 FIG. In the fourth and fifth embodiments, it goes without saying that the pixel electrode PX functioning as a reflection film may be replaced with a two-layer structure film as shown in FIG. 7 or FIG.

In this case, a transflective liquid crystal display device can be constructed.

Embodiment 7 FIG. FIG. 13 is a plan view showing another embodiment of the liquid crystal display device according to the present invention. FIG. 14 shows a cross section taken along line XIV-XIV, and FIG.
It is shown in FIG.

In this embodiment, the reflection film is provided with the function of the counter electrode CT in the first or fourth embodiment, and the pixel electrode PX is overlapped with the reflection film. Extend in the x direction in the figure and y
It consists of a plurality of electrode groups arranged side by side in the direction. Of course, they may be extended in the y direction and juxtaposed in the x direction. Various other configurations are possible as long as the shape of the PX has a thin line portion.

Since the reflection film is formed so as to be connected to the reflection film of another adjacent pixel region, the liquid crystal display unit AR is provided when it has the function of the counter electrode CT.
The counter voltage signal can be supplied from a portion (terminal) extending outside the region.

In this case, the liquid crystal LC is of a birefringence mode, and the orientation of molecules of the liquid crystal LC is controlled by an electric field having a component parallel to the transparent substrate SUB1 generated between the counter electrode CT and the pixel electrode PX. I am trying to do it.

The pixel electrode PX composed of a plurality of electrodes is formed as a pattern commonly connected at its lower end as shown in FIG. Is connected through a contact hole CH to the source electrode SD2 of the thin film transistor TFT formed in the above.

Further, a capacitive element Cstg having the protective film PSV3 as a dielectric film is formed between the pixel electrode PX and the counter electrode CT.

In the liquid crystal display device thus configured, the counter electrode CT is not formed on the transparent electrode SUB2 side because the counter electrode CT is formed on the transparent substrate SUB1 side on which the pixel electrode PX is formed. ing.

Note that, in this case as well, the counter electrode CT
7 or 8 instead of the reflective film
Needless to say, a two-layer structure film as shown in FIG. That is, a transflective liquid crystal display device can be configured.

[0114]

As is apparent from the above description, according to the liquid crystal display device of the present invention, it is possible to prevent the influence of the electric field from the signal line on the pixel electrode.

Also, the aperture ratio can be improved.

In addition, the characteristics of the thin film transistor can be stabilized.

Further, it is possible to provide a margin for the positioning of the substrates arranged to face each other via the liquid crystal.

[Brief description of the drawings]

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

FIG. 2 is a plan view showing one embodiment of the entire liquid crystal display device according to the present invention.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

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

FIG. 6 is a diagram showing an equivalent circuit when a capacitance element is formed between a pixel electrode and a capacitance line.

FIG. 7 is an explanatory view showing another embodiment of the pixel of the liquid crystal display device according to the present invention.

FIG. 8 is an explanatory view showing another embodiment of the pixel of the liquid crystal display device according to the present invention.

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

FIG. 10 is a sectional view taken along line XX of FIG. 9;

FIG. 11 is a sectional view taken along line XI-XI in FIG. 9;

FIG. 12 is a plan view showing another embodiment of the pixel of the liquid crystal display device according to the present invention.

FIG. 13 is a plan view showing another embodiment of the pixel of the liquid crystal display device according to the present invention.

FIG. 14 is a sectional view taken along line XIV-XIV in FIG. 14;

FIG. 15 is a sectional view taken along line XV-XV in FIG. 15;

[Explanation of symbols]

SUB: transparent substrate, GL: gate signal line, DL: drain signal line, PX: pixel electrode, TFT: thin film transistor, SD1: drain electrode, SD2: source electrode, Ca
dd, Cstg: capacitance element, CL: capacitance signal line, CT:
Counter electrode.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09F 9/30 349 G09F 9/30 349D 9/35 9/35 F-term (Reference) 2H090 HA04 LA01 LA04 2H091 FA16Y FD06 GA02 GA07 GA13 LA19 2H092 GA12 HA03 JA24 JA45 JB56 NA07 PA12 5C094 AA09 AA10 AA48 BA03 BA43 CA19 DA13 EA04 EA05 EA06 ED11 ED13 FA01 FA02 FB01 FB12 FB15

Claims (8)

[Claims] 1. A light-transmitting pixel electrode, and a first insulating film made of an organic material below the pixel electrode are formed in each pixel region on a liquid crystal side surface of one of the substrates opposed to each other with a liquid crystal interposed therebetween. And a thin film transistor arranged via a second insulating film having at least an organic material layer below the light reflecting film, wherein the light reflecting film is adjacent to another light reflecting film. The thin film transistor is formed by being connected in common with a light reflection film in a pixel region, and the pixel electrode is formed through a contact hole formed through the first insulation film and the second insulation film through an opening of the reflection film. A liquid crystal display device electrically connected to the liquid crystal display device. 2. A light-transmitting pixel electrode and a first insulating film made of an organic material beneath a pixel electrode in each pixel region on a liquid crystal side surface of one of the substrates opposed to each other with a liquid crystal interposed therebetween. And a thin film transistor arranged via a second insulating film having at least an organic material layer below the conductive film, wherein the conductive film is a region of a light-transmitting film. A light-reflecting portion that is scatteredly formed in the first insulating film; the pixel electrode is formed so as to be commonly connected to a conductive film of another adjacent pixel region; And a liquid crystal display device electrically connected to the thin film transistor by a contact hole formed through the second insulating film. 3. A pixel electrode serving also as a reflective film, and a first insulating film made of an organic material below the pixel electrode is formed in each pixel region on the liquid crystal side of one of the substrates opposed to each other with the liquid crystal interposed therebetween. And a thin film transistor arranged via a second insulating film having at least an organic material layer below the conductive film, wherein the conductive film is formed of another adjacent pixel region. The pixel electrode is formed so as to be commonly connected to a conductive film, and the pixel electrode is electrically connected to the thin film transistor through a contact hole formed in the first insulating film and the second insulating film through an opening of the conductive film. A liquid crystal display device. 4. A pixel electrode is provided in each pixel region on a liquid crystal side surface of one of the substrates arranged to face each other with a liquid crystal interposed therebetween.
A conductive film disposed below the first insulating film made of an organic material via a first insulating film; and a thin film transistor disposed below the conductive film via a second insulating film having at least an organic material layer. The conductive film is formed so as to be commonly connected to a conductive film of another adjacent pixel region, and the pixel electrode is formed of a light-reflecting portion or a reflective portion which is scattered in a light-transmitting film region. The thin film transistor is formed to have a light transmitting portion scatteredly formed in a region of the film, and is electrically connected to the thin film transistor through contact holes formed in the first insulating film and the second insulating film through openings of the conductive film. A liquid crystal display device connected to a liquid crystal display. 5. A pixel electrode serving also as a reflective film, and a first insulating film made of an organic material below the pixel electrode is provided in each pixel region on a liquid crystal side surface of one of the substrates opposed to each other with a liquid crystal interposed therebetween. A light-transmissive conductive film disposed through the conductive film, and a thin film transistor disposed through a second insulating film having at least an organic material layer below the conductive film, wherein the conductive film is adjacent to the conductive film. The pixel electrode is formed so as to be commonly connected to the conductive film of another pixel region, and covers the thin film transistor.
The first insulating film and the second insulating film pass through an opening of the conductive film.
A liquid crystal display device, wherein the liquid crystal display device is electrically connected to the thin film transistor by a contact hole formed through the insulating film. 6. A pixel electrode in each pixel region on a liquid crystal side surface of one of substrates opposed to each other with a liquid crystal interposed therebetween.
A light-transmitting conductive film is disposed under the first insulating film made of an organic material, and a second insulating film having at least an organic material layer is formed under the conductive film. The conductive film is formed so as to be commonly connected to a conductive film of another adjacent pixel region, and is formed so as to cover the thin film transistor. A light reflecting portion formed scatteredly in the region of the reflective film or a light transmitting portion formed scatteredly in the region of the reflective film, and the light-transmitting portion is formed through the opening of the conductive film. A liquid crystal display device, wherein the liquid crystal display device is electrically connected to the thin film transistor through a contact hole formed through the first insulating film and the second insulating film. 7. An electrode group extending in one direction and juxtaposed in a direction intersecting with the liquid crystal side surface of one of the substrates disposed opposite to each other with the liquid crystal interposed therebetween. A pixel electrode, a counter electrode formed of a non-light-transmitting conductive film disposed under the first insulating film formed of an organic material below the pixel electrode, and at least an organic material layer formed below the counter electrode. A thin film transistor disposed via a second insulating film, wherein the counter electrode is formed so as to be commonly connected to a counter electrode of another adjacent pixel region, and formed so as to cover the thin film transistor. And the pixel electrode is electrically connected to the thin film transistor through a contact hole formed through the first insulating film and the second insulating film through an opening of the counter electrode. A liquid crystal display device. 8. An electrode group extending in one direction and juxtaposed in a direction intersecting with the pixel region on a liquid crystal side surface of one of the substrates opposed to each other with the liquid crystal interposed therebetween. A pixel electrode, a counter electrode made of a conductive film disposed under the first insulating film made of an organic material under the pixel electrode, and a second insulating film having at least an organic material layer under the counter electrode. And a thin film transistor that is disposed through the thin film transistor. The counter electrode is formed so as to be commonly connected to a counter electrode of another adjacent pixel region, and is formed so as to cover the thin film transistor. The electrode is formed having a light reflecting portion formed scatteredly in the region of the light-transmitting film or a light transmitting portion formed scatteredly in the region of the reflective film. The electrode is an opening of the counter electrode. The liquid crystal display device characterized by being electrically connected to the thin film transistor by said first insulating film and a second contact hole which is formed through the insulating film through.