JPH11305262A - Liquid crystal display device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display(LCD) device capable of reducing a parasitic capacitance value, reducing the variation of pixel voltage after writing and the delay of signal voltage to be written in a pixel and displaying a fine picture as compared with a conventional device. SOLUTION: In the LCD device having a pair of substrates 11, 12 opposed to each other, liquid crystal(LC) 10 is sealed between the substrates 11, 12 and at least one of the substrates 11, 12 is provided with pixel electrodes 25 for applying voltage to the LC 10 and thin film transistors(TFTs) 30 for controlling the applied voltage. In the LCD device, a composite insulating layer consisting of a 1st insulating film 40 and a 2nd insulating film 41 of which dielectric constant is lower than that of the film 40 is formed on wiring 22 for driving each TFT 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal display device and a method of manufacturing the same, and more particularly, to a liquid crystal display device having a pixel electrode and a switching element on at least one of a pair of substrates facing each other.

[0002]

2. Description of the Related Art FIG. 12 is a sectional view showing the structure of a conventional liquid crystal display. A gate electrode 21, a gate insulating film 23, a semiconductor layer 24 formed by performing a photolithography (PR) process and an etching process on a metal film, an insulating film, or a semiconductor film on the substrate 11.
Thin film transistor (TFT) comprising drain electrode 22
30 and a pixel electrode 25 are provided. On the substrate 11, a gate wiring and a drain wiring for driving the TFT element 30 are further formed.

[0005] If necessary, a storage capacitor line 26 for forming a storage capacitor 72 with the pixel electrode 25 is formed. Elements such as the pixel electrode 25, the TFT 30, and the storage capacitor wiring 26 on the substrate 11 are insulated by an insulating film 40 such as a silicon nitride film or a silicon oxide film. The liquid crystal 10 is sealed between the substrate 11 thus formed and the transparent substrate 12 on which the transparent electrode 20 is formed. In this liquid crystal display device, the pixel electrode 25 and the transparent electrode 2
The display is performed by applying a required voltage between 0 and 0.

[0004]

In the liquid crystal display device having the above structure, the drain electrode 22 and the drain electrode 22
, A parasitic capacitance 70 is generated between the pixel electrode 25 and the drain electrode 22 and the pixel electrode 25. Further, parasitic capacitance is also generated between the gate line and the counter electrode 20, between the gate line and the pixel electrode 25, and between the gate line and the drain line. As described above, when a parasitic capacitance is generated between the wiring and the electrode, the voltage of the pixel electrode fluctuates due to the influence of the parasitic capacitance after the voltage is applied to the liquid crystal 10. Further, there is a problem that a signal voltage transmitted through the wiring is delayed due to the parasitic capacitance, and a writing rate to liquid crystal is reduced. In addition, if the gate electrode voltage is delayed, writing is performed even after the gate electrode is turned off, which causes a problem that a feedthrough voltage difference occurs. Therefore, in order to perform good display, it is necessary to reduce each parasitic capacitance value.

[0005] When a DC voltage is applied to the liquid crystal for a long time, a deterioration phenomenon such as a change in material properties and a decrease in resistivity appears. For this reason, in a liquid crystal display device, in general, AC driving is performed by inverting the polarity of a driving voltage from the viewpoint of the life of a liquid crystal panel.

[0006] The feed-through phenomenon occurs because charges charged in the parasitic capacitances when the gate pulse is turned on are redistributed to the capacitors at the moment when the gate pulse is turned off. Since the potential of the feed-through voltage ΔVp attenuates in the direction of 0 V in both positive and negative writing, the positive and negative display signal potentials differ by ΔVp. In this state, the positive and negative writing potentials are different. A DC offset component occurs between them. Offset components cause image quality deterioration such as image sticking,
Unbalance between the positive and negative pixel potentials causes flicker. Therefore, it is necessary to correct the potential of the transparent electrode 20, which is the opposite electrode, by the offset potential so that a positive / negative balance is maintained to prevent image quality deterioration.

In order to realize this, in the liquid crystal display device shown in FIG. 12, a storage capacitor 72 is added so as to be in parallel with the pixel capacitance (liquid crystal capacitance) to suppress the feedthrough voltage difference. By increasing the storage capacitance 72, the feedthrough voltage ΔVp can be reduced. Here, if the storage capacitor 72 is increased, the effect of reducing the feedthrough voltage ΔVp can be increased, but the area of the storage capacitor wiring 26 also increases accordingly.

When the area of the storage capacitor wiring 26 increases,
The following disadvantages occur. That is, if the liquid crystal display device shown in FIG.
However, there is no problem with the aperture ratio because the pixel electrode 25 is located at a position hidden from the display side. However, in the case of a transmissive liquid crystal display device, when light entering from the transparent substrate 12 side passes through the pixel electrode 25 which is made transparent in this situation and travels toward the substrate 11 side, the pixel electrode 25 It passes through the portion of the storage capacitor wiring 26 which overlaps and has a large area. Normally, since the storage capacitor wiring 26 is formed of the same metal layer as the gate electrode 21 and blocks light, there arises a problem that the aperture ratio of the pixel in the liquid crystal display decreases.

In view of the above, the present invention can reduce the parasitic capacitance value, reduce the fluctuation of the pixel voltage after writing, and the delay of the signal voltage to be written to the pixel, and perform better display than before. It is an object of the present invention to provide a liquid crystal display device and a manufacturing method thereof. Another object of the present invention is to provide a liquid crystal display device capable of improving the aperture ratio of a pixel.

[0010]

In order to achieve the above object, a liquid crystal display device of the present invention has a pair of substrates facing each other, and a liquid crystal is sealed between the pair of substrates. In at least one of the substrates, a pixel electrode for applying a voltage to the liquid crystal, and a switching device for controlling the applied voltage, in a liquid crystal display device, on the wiring for driving the switching element, A composite insulating layer including a first insulating film and a second insulating film having a lower dielectric constant than the first insulating film is provided.

In the liquid crystal display device of the present invention, the parasitic capacitance value can be reduced by forming the second insulating film on the wiring for driving the switching element. It is possible to reduce the delay of the incorporated signal voltage as compared with the related art.

The liquid crystal display device of the present invention has a pair of substrates facing each other, a liquid crystal is sealed between the pair of substrates, and a voltage is applied to the liquid crystal to at least one of the pair of substrates. In a liquid crystal display device having a pixel electrode for performing switching and a switching element for controlling the applied voltage, a low dielectric constant material having a relative dielectric constant of 4 or less is provided on a wiring for driving the switching element. And an insulating layer including the insulating layer.

In the liquid crystal display device of the present invention, the parasitic capacitance value can be reduced by forming the low dielectric constant material layer on the wiring for driving the switching element. It is possible to reduce the delay of the embedded signal voltage as compared with the related art. The low dielectric constant substance in the present invention means a substance having a lower dielectric constant than, for example, a silicon nitride film or a silicon oxide film, and may be an organic substance or an inorganic substance, such as a polyester resin or an acrylic resin. .

Here, it is preferable that the insulating layer containing the low dielectric substance is formed as a mixed layer containing the low dielectric substance and a polymer resin holding the low dielectric substance. Thereby, formation of the low dielectric constant material layer is ensured.

The manufacturing method according to the present invention is a manufacturing method for manufacturing the liquid crystal display device, wherein the substrate on which the switching element is formed is immersed in an electrolytic solution, and a wiring for driving the switching element is connected to a direct current. The second insulating film connected to the anode side of the power supply, the conductive electrode immersed in the electrolytic solution is connected to the cathode side of the DC power supply, and the second insulating film or the low dielectric Forming an insulating layer containing a refractive index substance.

According to the manufacturing method of the present invention, the second insulating film or the insulating layer containing a low dielectric constant material can be formed only on the specific electrode, that is, the wiring for driving the switching element. This eliminates the need for the PR step and the etching step conventionally required for forming a film having a desired pattern.

A liquid crystal display device according to the present invention has a pair of substrates facing each other, a liquid crystal is sealed between the pair of substrates, and a voltage is applied to the liquid crystal to at least one of the pair of substrates. In the liquid crystal display device having the pixel electrode of the above, a storage capacitor line for forming a storage capacitor is provided, and a first insulating film and a first insulating film are provided between the storage capacitor line and the pixel electrode. Also, a composite insulating layer comprising a second insulating film having a high dielectric constant is provided.

The liquid crystal display device of the present invention has a pair of substrates facing each other, a liquid crystal is sealed between the pair of substrates, and a voltage is applied to the liquid crystal to at least one of the pair of substrates. A liquid crystal display device having a pixel electrode for forming a storage capacitor, a storage capacitor line for forming a storage capacitor, and a high dielectric constant material having a relative dielectric constant of 7 or more between the storage capacitor line and the pixel electrode. An insulating layer including:

According to the liquid crystal display device of the present invention, even when the electrode area of the storage capacitor is reduced to 1/2 or 1/3,
Since the dielectric constant between the storage capacitors can be doubled or tripled as compared with the conventional one, a storage capacitor having the same capacitance value as the conventional one can be formed. In other words, it is possible to form a large-capacity storage capacitor with a small area, so that the area of the storage capacitor wiring overlapping with the pixel electrode can be reduced, preventing a decrease in the aperture ratio of the pixel, The aperture ratio can be improved. By applying the present invention as described above to a liquid crystal display device, it is possible to perform better display than before.

The high dielectric constant material in the present invention means a material having a higher dielectric constant than, for example, a silicon nitride film or a silicon oxide film, and may be an organic material or an inorganic material, such as alumina or barium titanate. Can be

[0021] Preferably, the insulating layer containing the high dielectric substance is formed as a mixed layer containing a high dielectric substance and a polymer resin holding the high dielectric substance. Thereby, the formation of the high dielectric constant material layer is ensured.

The manufacturing method according to the present invention is a manufacturing method for manufacturing the liquid crystal display device, wherein the substrate on which the storage capacitor wiring is formed is immersed in an electrolytic solution, and the storage capacitor wiring is connected to an anode side of a DC power supply. And the conductive electrode immersed in the electrolytic solution is connected to the cathode side of the DC power supply, and the second insulating film or the insulating layer containing the high dielectric substance is formed on the storage capacitor wiring. It is characterized by the following.

According to the manufacturing method of the present invention, the second insulating film or the insulating layer containing the high dielectric substance can be formed only on the storage capacitor wiring which is a specific electrode. The PR step and the etching step required for film formation are not required.

[0024]

The present invention will be described in more detail with reference to the drawings. FIG. 1 is a sectional view showing a liquid crystal display device according to one embodiment of the present invention. This liquid crystal display device is applicable to both transmission type and reflection type liquid crystal display devices, and is manufactured as follows. First, on the substrate 11,
By subjecting a conductive film such as a metal to a photolithography (PR) step and an etching step, a gate electrode 21 is formed.
To form Next, the laminated film of the insulating layer and the semiconductor layer,
The PR process and the etching process are performed, and the gate insulating film 2 is formed.
3 and the semiconductor layer 24 are formed. In addition, P
By performing an R step and an etching step, a drain wiring 22 is formed, and a thin film transistor (TFT) 30 as a switching element is formed.

On the substrate 11, a conductive film and an insulating film
By performing the R step and the etching step, insulation between the pixel electrode 25 itself and the gap between the pixel electrode 25 and the TFT 30 are achieved.
Alternatively, an insulating layer 40 for achieving insulation between the pixel electrode 25 and each wiring is formed. On a transparent substrate 12 facing the substrate 11, a transparent electrode 20 is formed.
The liquid crystal 10 is sealed between the substrate and the transparent substrate 12. Then, display is performed by applying a voltage between the transparent electrode 20 and the pixel electrode 25.

On the surface of the drain wiring 22, a low dielectric constant material layer 41 having a lower dielectric constant than a silicon nitride film or a silicon oxide film used as an insulating film in a conventional liquid crystal display device is formed. Here, the drain wiring 2
A parasitic capacitance 70 is formed between the drain wiring 22 and the transparent electrode 20 on the transparent substrate 12, and a parasitic capacitance 71 is formed between the drain wiring 22 and the pixel electrode 25. The parasitic capacitance value decreases as the dielectric constant of the low dielectric constant material layer 41 decreases.
The value becomes smaller as the thickness of the low dielectric constant material layer 41 is larger. Note that the low dielectric constant material layer 41 of the present invention
It may also serve as 0. That is, the insulating layer 40 may be formed of the same material as the low dielectric constant material layer 41.

Further, instead of the switching element of FIG.
A staggered TFT 31 having a structure as shown in FIG. 2 or a MIM (Metal Insulator Metal) comprising a pixel electrode 23, a signal wiring 33 and an insulating film 34 as shown in FIG.
Element 32 can also be used. The pixel electrode 25 may be an electrode having a structure having an uneven shape on the surface. Note that the pixel electrode 25 includes the drain wiring 22 and the gate wiring 2.
1 may not be overlapped with the transparent substrate 12.
May be formed with a coloring element for performing color display.

Further, the transparent electrode 20 on the transparent substrate 12
A solid film simply formed in a flat shape or a patterned film may be used. Further, the low dielectric constant material layer 41 may be an organic substance or an inorganic substance, or may be a mixture of a plurality of substances. The dielectric constant of the low dielectric constant material layer of the present invention is smaller than the dielectric constant of a silicon nitride film or a silicon oxide film conventionally used to insulate pixel electrodes and wirings. It is desirable that: Examples of such a material include a polyester resin and an acrylic resin.

FIG. 4 is a sectional view of a liquid crystal display device according to a second embodiment of the present invention. This embodiment is an example in which a storage capacitor is added so as to be in parallel with the pixel capacitance. On the substrate 11, as in the first embodiment, the gate electrode 21,
Gate insulating film 23, semiconductor layer 24 and drain wiring 22
, A pixel electrode 25, an insulating layer 40, and a low dielectric constant material layer 41. Further, on the substrate 11, a storage capacitor line 26 having the same conductivity as the gate electrode 21 and formed by the same PR step and etching step is provided. Thus, a storage capacitor 72 is formed between the pixel electrode 25 and the storage capacitor line 26.

On the storage capacitor wiring 26, a high dielectric material layer 42 having a higher dielectric constant than a silicon nitride film or a silicon oxide film used as an insulating film in a conventional liquid crystal display device is formed. . For this reason, even when the electrode area of the storage capacitor 72 is reduced to one half or one third, the dielectric constant between the storage capacitors is doubled or tripled compared with the conventional one,
It is possible to form a storage capacitor having the same capacitance value as in the related art. Therefore, the area of the storage capacitor line 26 overlapping the pixel electrode can be reduced. Therefore, when the present liquid crystal display device is of a transmission type or the like, it is possible to prevent a decrease in the aperture ratio of pixels. This is particularly effective in a liquid crystal display device having a large number of pixels, in which it is difficult to increase the pixel area. The high dielectric constant material layer 42 has a value larger than the dielectric constant of a silicon nitride film or a silicon oxide film conventionally formed to insulate between a pixel electrode and a storage capacitor wiring, and has a relative dielectric constant of 7 or more. Preferably, the substance is Such materials include alumina, barium titanate, and the like.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIGS. 5 and 6 are cross-sectional views for explaining a method of manufacturing a liquid crystal display device in this embodiment. First, a metal layer such as chromium (Cr) was formed on the surface of a substrate 32 such as glass by sputtering, a resist was applied to the metal film, and exposure and development were performed to form a gate electrode pattern. Further, the Cr film was etched using the resist as a mask to form a gate electrode 21 (FIG. 5A).

Next, a laminated film of a silicon nitride film and an amorphous silicon layer was formed by a chemical vapor deposition (CVD) method. Further, by performing a PR process and an etching process on the laminated film, an island pattern of the gate insulating film 23 and the amorphous silicon layer 24 was formed (FIG. 5B). Next, a metal layer such as Cr is formed by sputtering, and a PR process and Cr
The drain electrode 22 was formed by performing an etching process (FIG. 5C).

The TFT 3 formed through the above steps
The following processing is applied to the substrate 32 having 0 using the apparatus shown in FIG. For example, a low dielectric constant polyester resin 61 formed into micelles with a surfactant 52 or the like.
The substrate 32 is immersed in an electrolytic solution containing the polymer resin 63 such as a polyester resin for holding the resin 61 having a low dielectric constant. Further, a voltage was applied by connecting to a DC power supply 53 with the conductive electrode 51 immersed in the electrolytic solution as the cathode side and the metal layer 55 electrically connected to the drain electrode 22 as the anode side.

At this time, on the drain electrode 22 immersed in the electrolytic solution, electrons are exchanged between the low dielectric constant material 61 in the electrolytic solution and the surface active material 52 which is formed into micelles. , The resin 6 in the electrolytic solution on the drain electrode 22
1 (low dielectric constant material) and a polymer resin 63 holding the resin 61 were deposited to form a low dielectric constant material layer 41. The thickness of the low dielectric constant material layer 41 deposited on the drain electrode 22 can be easily controlled by adjusting the current and the time.

Since the low dielectric constant material layer 41 of the present invention formed by such a method can be selectively formed only on a specific electrode, the PR process conventionally required for forming a film of a desired pattern is conventionally required. In addition, an etching step is not required.

FIG. 7 is a sectional view showing the substrate of the liquid crystal display device of the present invention and its periphery. Low dielectric constant substance 4 of the present invention
An insulating layer 40 such as a silicon nitride film is formed on the substrate 32 on which 1 is formed, a PR process and an etching process are performed on the insulating layer 40, and a contact hole 35 is formed.
Further, a conductive material such as ITO is formed into a film, and PR is formed.
The pixel electrode 25 was formed by performing a process and an etching process. The liquid crystal display device as shown in FIG. 1 was formed by laminating the main substrate 32 with the transparent substrate 12 (FIG. 1) and cutting unnecessary peripheral portions including the metal layer 55.

Embodiment 2 FIGS. 8 and 9 are views for explaining a method of manufacturing a liquid crystal display device in this embodiment. A metal such as Cr was formed on the glass substrate 32. The drain electrode 22 was formed by subjecting this metal film to a PR process and a Cr etching process (FIG. 8A). Next, the amorphous silicon layer 24, the silicon nitride film 36, and the Cr film 37
(FIG. 8B), and a PR process and an etching process are performed on the laminated film, so that the gate electrode 21 and
An island of the gate insulating film 23 and the amorphous silicon 24 was formed (FIG. 8C).

The TFT 31 formed by the steps described above
The following processing is applied to the substrate 32 having For example, a low dielectric constant polyester-based resin 61 formed into micelles with a surfactant 52 or the like,
The substrate 32 is placed in an electrolytic solution containing a polymer resin 63 such as a polyester resin for holding the resin 61 having a low dielectric constant.
Soak. Further, the gate electrode 21 and the drain electrode 2
The metal layer 56 and the metal layer 55 electrically connected to the second electrode 2 were connected to a DC power supply 53, respectively, on the anode side, and the electrode 51 immersed in the electrolytic solution was set on the cathode side.

As a result, similarly to the case of forming on the drain electrode 22 in the first embodiment, the low-dielectric-constant material layer 41 composed of the low-dielectric substance 61 and the polymer resin 63 is formed on the gate electrode 21 and the drain electrode 22. Respectively.

Embodiment 3 FIGS. 10 and 11 are diagrams for explaining a method of manufacturing a liquid crystal display device in this embodiment. In FIG.
The low dielectric substance 61 in the electrolytic solution in FIG. 6 is replaced with a high dielectric substance 62 such as barium titanate. As in Examples 1 and 2, the polymer resin 63 is added to the electrolytic solution. First, a TFT 30 is formed on a substrate 32 in the same manner as in the first embodiment.
The storage capacitor wiring 26 was formed using the same Cr layer as the gate electrode 21 of No. 0. The storage capacitor wiring 26 is electrically connected to a metal layer 57 formed on the periphery of the substrate 32.

For example, a high dielectric substance 62 such as barium titanate, which is formed into a micelle with a surfactant 52 or the like, is used.
The substrate 32 was immersed in an electrolytic solution containing a polymer resin 63 such as a polyester resin for holding the high dielectric substance 62. A voltage was applied by connecting to a DC power supply 53 with the metal layer 57 on the anode side and the conductive electrode 51 immersed in the electrolytic solution on the cathode side. At this time, the high dielectric substance 62 in the electrolytic solution and the polymer resin 63 holding the high dielectric substance 62 were deposited on the storage capacitor wiring 26 to form the high dielectric substance layer 42. In this way,
After forming the high dielectric constant material layer 42 on the storage capacitor wiring 26, as shown in FIG. 11, an insulating film 40 was formed, a contact hole 35 was formed, and the pixel electrode 25 was formed.

As described above, according to the embodiment and the example to which the present invention is applied, the insulation between the wiring and the pixel electrode, between the wiring and the counter electrode, between the gate wiring and the drain wiring, and the like. Since the low dielectric constant material layer made of the conductive material is formed, the parasitic capacitance value can be reduced. Thereby, in the liquid crystal display device at the time of driving, the fluctuation width of the fluctuation of the pixel electrode voltage due to the change of the drain wiring or the gate wiring voltage can be suppressed. Therefore, the fluctuation of the pixel voltage after writing and the delay of the signal voltage supplied to the pixel electrode (writing to the pixel) can be reduced as compared with the related art, and good display can be performed.

Although the present invention has been described based on the preferred embodiments, the liquid crystal display device and the method of manufacturing the same according to the present invention are not limited to the above embodiments and examples. A liquid crystal display device with various modifications and changes from the embodiments and examples and a method of manufacturing the same are also included in the scope of the present invention.

[0044]

As described above, according to the liquid crystal display device and the method of manufacturing the same of the present invention, the parasitic capacitance can be reduced.
Variation in pixel voltage after writing and delay in signal voltage to be written to the pixel can be reduced, and better display can be performed as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating an example in which a switching element of the liquid crystal display device according to the first embodiment is a staggered TFT.

FIG. 3 is a cross-sectional view illustrating an example in which a switching element of the liquid crystal display device according to the first embodiment is an MIM element.

FIG. 4 is a sectional view showing a liquid crystal display device according to a second embodiment of the present invention.

FIGS. 5A to 5C are cross-sectional views illustrating a method for manufacturing the liquid crystal display device according to the first embodiment of the present invention, wherein FIGS.
Indicate different manufacturing stages.

FIG. 6 is a schematic view for explaining the method for manufacturing the liquid crystal display device according to the first embodiment.

FIG. 7 is a cross-sectional view illustrating a substrate of the liquid crystal display device according to the first embodiment and its periphery.

FIGS. 8A to 8C are cross-sectional views illustrating a method for manufacturing a liquid crystal display device according to a second embodiment of the present invention, wherein FIGS.
Indicate different manufacturing stages.

FIG. 9 is a schematic view for explaining the method for manufacturing the liquid crystal display device according to the second embodiment.

FIG. 10 is a schematic diagram for explaining the method for manufacturing the liquid crystal display device according to the third embodiment of the present invention.

FIG. 11 is a cross-sectional view illustrating a substrate of a liquid crystal display device and a periphery thereof according to a third embodiment.

FIG. 12 is a cross-sectional view illustrating a structure of a conventional liquid crystal display device.

[Explanation of symbols]

 Reference Signs List 10 liquid crystal 11, 32 substrate 12 transparent substrate 21 gate electrode 22 drain electrode 23 gate insulating film 24 amorphous silicon layer 25 pixel electrode 26 storage capacitor wiring 30, 31 thin film transistor 33 wiring 34 MIM element insulating layer 35 contact hole 40 insulating layer 41 low dielectric constant Material layer 42 High permittivity material layer 51 Electrode 52 Surfactant 53 DC power supply 55, 56, 57 Metal layer 61 Low permittivity material 62 High permittivity material 63 Polymer resin 70, 71 Parasitic capacitance 72 Storage capacitance

Claims (8)

[Claims] A liquid crystal is sealed between the pair of substrates, and a pixel electrode for applying a voltage to the liquid crystal is provided on at least one of the pair of substrates. A liquid crystal display device comprising a switching element for controlling an applied voltage, wherein a first element is provided on a wiring for driving the switching element.
And a second insulating film having a dielectric constant lower than that of the first insulating film. 2. A liquid crystal display device comprising: a pair of substrates opposed to each other; a liquid crystal sealed between the pair of substrates; and a pixel electrode for applying a voltage to the liquid crystal to at least one of the pair of substrates; In a liquid crystal display device having a switching element for controlling an applied voltage, an insulating layer containing a low dielectric constant substance having a relative dielectric constant of 4 or less is disposed on a wiring for driving the switching element. A liquid crystal display device characterized by the above-mentioned. 3. The insulating layer containing a low dielectric constant material is formed as a mixed layer containing a low dielectric constant material and a polymer resin holding the low dielectric constant material. 3. The liquid crystal display device according to 1. 4. The method for manufacturing a liquid crystal display device according to claim 1, wherein the substrate on which the switching elements are formed is immersed in an electrolytic solution, and the switching is performed. A wiring for driving the element is connected to the anode side of the DC power supply, a conductive electrode immersed in the electrolytic solution is connected to the cathode side of the DC power supply, and the wiring is connected to the wiring for driving the switching element. 2. A manufacturing method, comprising: forming an insulating film of No. 2 or an insulating layer containing the low dielectric constant substance. 5. A semiconductor device comprising: a pair of substrates facing each other; a liquid crystal sealed between the pair of substrates; and a pixel electrode for applying a voltage to the liquid crystal on at least one of the pair of substrates. In a liquid crystal display device, a storage capacitor line for forming a storage capacitor is provided, and a first insulating film and a second insulating film having a higher dielectric constant than the first insulating film are provided between the storage capacitor line and the pixel electrode. 2. A liquid crystal display device comprising: a composite insulating layer comprising: a second insulating film. 6. A pair of substrates facing each other, liquid crystal is sealed between the pair of substrates, and at least one of the pair of substrates includes a pixel electrode for applying a voltage to the liquid crystal. In a liquid crystal display device, a storage capacitor line for forming a storage capacitor is provided, and an insulating layer containing a high dielectric constant material having a relative dielectric constant of 7 or more is provided between the storage capacitor line and the pixel electrode. A liquid crystal display device characterized in that: 7. The insulating layer containing the high dielectric constant material is formed as a mixed layer containing a high dielectric constant material and a polymer resin holding the high dielectric constant material. 3. The liquid crystal display device according to 1. 8. The method for manufacturing a liquid crystal display device according to claim 5, wherein the substrate on which the storage capacitor wiring is formed is immersed in an electrolytic solution. The storage capacitor wiring is connected to the anode side of the DC power supply, the conductive electrode immersed in the electrolytic solution is connected to the cathode side of the DC power supply, and the second insulating film or the high dielectric A method of forming an insulating layer containing an insulating material.