JP2010091904A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device having a large aperture ratio and prevents flickers, crosstalk or the like, in which an auxiliary capacitance can be made larger than a conventional liquid crystal display device by preparing a transparent lower electrode for the auxiliary capacitance, in addition to an auxiliary capacitance wiring line. <P>SOLUTION: The display includes: a transparent conductive lower electrode 15 for an auxiliary capacitance, electrically connected to an auxiliary capacitance line 13; a first insulating film 16 covering a scanning line 12, the auxiliary capacitance line 13 and the lower electrode 15 for the auxiliary capacitance; a second insulating film 19 covering a TFT; and a transparent conductive pixel electrode 21 electrically connected to the TFT through a contact hole 20 penetrating the second insulating film 19. The lower electrode 15 for the auxiliary capacitance, the pixel electrode 21, and the first and second insulating films 16, 19 constitute the auxiliary capacitance. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a liquid crystal display device, and particularly has a large auxiliary capacitance with a transparent auxiliary capacitance electrode,
In addition, the present invention relates to a liquid crystal display device having a large aperture ratio.

A liquid crystal display device has characteristics of light weight, thinness, and low power consumption as compared with a CRT (cathode ray tube), and thus is used in many electronic devices for display.

As a method for applying an electric field to a liquid crystal layer of a liquid crystal display device, there are a vertical electric field method and a horizontal electric field method. A vertical electric field type liquid crystal display device applies a substantially electric field in a column direction to liquid crystal molecules by a pair of electrodes arranged with a liquid crystal layer interposed therebetween. As this vertical electric field type liquid crystal display device, TN (Twisted Nematic) mode, VA (Vertical Alignment) mode, MV
An A (Multi-domain Vertical Alignment) mode or the like is known. Among these, a general configuration of a conventional TN mode liquid crystal display device will be described with reference to FIGS.

FIG. 6 is a plan view of one sub pixel of a conventional TN mode liquid crystal display device. 7 is the same as FIG.
It is sectional drawing of a VII-VII line. 8 is a cross-sectional view taken along line VIII-VIII in FIG. FIG. 9A is a schematic equivalent circuit diagram of one sub-pixel portion of the liquid crystal display device shown in FIG. 6, and FIG. 9B is a diagram showing voltage waveforms of each portion of the one sub-pixel of the liquid crystal display device shown in FIG. .

The conventional liquid crystal display device 50 has a configuration in which a liquid crystal LC is sealed between an array substrate AR and a color filter substrate CF that are arranged to face each other. The array substrate AR is a first transparent substrate 11.
A plurality of scanning lines 12 and signal lines 18 are formed in a matrix on the first transparent substrate 11 with the gate insulating film 16 interposed therebetween. A storage capacitor lower electrode 51 and a pixel electrode 21 are provided for each region surrounded by the scanning lines 12 and the signal lines 18.
Is equivalently represented by a liquid crystal capacitance C _LC in FIG. 9A. Normally, the auxiliary capacitor Cs formed by the drain electrode D made of the lower electrode 51 and the storage capacitor upper electrode auxiliary capacitor is connected in parallel to the liquid crystal capacitance C _LC. One end of the liquid crystal capacitance C _LC is connected to the thin film transistor TFT (Thin Film Transistor) as a driving switching element, the other end through the color filter layer 24 and topcoat layer 25 on the surface of the second transparent substrate 23 A predetermined common potential Vc is applied to the common electrode 26 provided.

The source electrode S of the TFT is connected to the signal line 18 and supplied with the image signal Vs.
The drain electrode D of the FT is connected through a contact hole 20 at one end of the liquid crystal capacitance C _LC, i.e., the pixel electrode 21. Further, the gate electrode G of the TFT is connected to the scanning line 12 so that a gate pulse Vg having a predetermined voltage is applied. In the liquid crystal display device 50 shown here, the TFTs, the scanning lines 12 and the signal lines 18 are covered so as to cover them.
A passivation film 19 and an interlayer film 34 are provided on the entire surface of the first transparent substrate 11. The pixel electrode 21 is formed on the surface of the interlayer film 34 and the contact hole 20.
Is electrically connected to the drain electrode D of the TFT. A liquid crystal LC is sealed between the pixel electrode 21 and the common electrode 26.

In the liquid crystal display device 50, a coupling capacitor is formed between the liquid crystal capacitor _CLC and the gate electrode G. The binding capacity are those which combine to parasitic capacitance component C _GD between the floating capacitance component C _SD and TFT internal gate region and the drain region between the scan line 12 and pixel electrode 21, the latter parasitic capacitance component _CGD is dominant and the value varies considerably among individual TFTs.

The voltage waveform of each part of this one pixel will be described with reference to FIG. 9B. In the liquid crystal display device 50, the common potential Vc applied to the common electrode 26 is periodically inverted, and a bias voltage that periodically inverts the image signal Vs applied to the signal line 18 is superimposed. Has been. First, when the gate pulse Vg is applied to the gate electrode G during the selection period of a predetermined subpixel, the TFT of this subpixel is turned on. At this time, the image signal Vs supplied from the signal line 18 is written into the pixel electrode 21 via the TFT, and so-called sampling is performed. Next, when this sub-pixel is in a non-selection period, the application of the gate pulse Vg is stopped and a low-level gate voltage is applied, and the TFT is turned off, but the written image signal is held in the liquid crystal capacitor _CLC. ing.

When shifting from the selection period to the non-selection period, the rectangular wave gate pulse Vg suddenly falls from the high level to the low level. At this time, the charge stored in the liquid crystal capacitor _CLC by the coupling via the coupling capacitance described above. Discharges momentarily. For this reason, a voltage shift ΔV (not shown) occurs in the image signal Vs written to the pixel electrode 21. Accordingly, since the coupling capacitance value varies for each sub-pixel of the liquid crystal display device 50, the voltage shift ΔV also varies. As a result, the display screen of the liquid crystal display device 50 is periodically changed, So-called flickers and afterimages are produced and display quality is significantly deteriorated.

Conventionally, for suppressing the absolute amount and the variation of the voltage shift [Delta] V, measures that large form the auxiliary capacitor Cs are connected in parallel to the liquid crystal capacitance C _LC had been taken. That is, a charge sufficient to supplement the amount of charge discharged through the coupling capacitor is stored in advance in the auxiliary capacitor Cs. The auxiliary capacitance portion Cs overlaps the drain electrode D of the TFT electrically connected to the pixel electrode 21 serving as the auxiliary capacitance upper electrode in a plan view, with the auxiliary capacitance lower electrode 51 independent from the other electrodes. A so-called Cs on Common storage capacitor type is often used which is arranged and applies a voltage common to the common electrode 26 to the auxiliary capacitor lower electrode 51.

In recent years, miniaturized liquid crystal display devices for portable devices have been improved in definition, and accordingly, crosstalk due to parasitic capacitance between electrodes / wiring is likely to occur, so that a large auxiliary capacitance Cs is required. ing. In order to ensure such a large auxiliary capacity, the following Patent Document 1
Discloses an invention of a liquid crystal display device in which a first auxiliary capacitance electrode and a pixel electrode are overlapped, and a second auxiliary capacitance electrode connected to the auxiliary capacitance line is overlapped with the first auxiliary capacitance electrode. ing.
Further, in Patent Document 2 below, an auxiliary capacitance electrode and an auxiliary capacitance line are formed separately and superimposed on different layers, a first auxiliary capacitance is formed between the pixel electrode and the auxiliary capacitance line, and an auxiliary capacitance is used. An invention of a liquid crystal display device in which a second auxiliary capacitance is formed between an electrode and an auxiliary capacitance line is disclosed.

However, in the liquid crystal display devices disclosed in Patent Documents 1 and 2, the auxiliary capacitor Cs is formed in the pixel electrode region, and if this dimension is set large, the aperture ratio of the pixel is sacrificed. It becomes impossible to obtain a good display contrast and to secure the transmittance (brightness). On the other hand, in Patent Document 3 below, as shown in FIG. 10, the auxiliary capacitance electrode 51 is composed of two types of layers in which a transparent conductive layer 53 is added to a conventional opaque metal layer 52 for display. An invention of a liquid crystal display device is disclosed in which the pixel electrode 21 made of a transparent conductive material is also used as an upper electrode of an auxiliary capacitor so that the aperture ratio is increased.

10 is a schematic cross-sectional view of the array substrate of the liquid crystal display device disclosed in the above cited reference 3. In FIG. 10, the same components as those of the conventional liquid crystal display device 50 shown in FIGS. Are given the same reference numerals and their detailed explanation is omitted.
JP-A-5-265035 Japanese Patent Laid-Open No. 5-265036 JP-A-5-323378

However, in the liquid crystal display device disclosed in Patent Document 3, the pixel electrode 21 made of a transparent conductive material for display is directly connected to the drain electrode D of the TFT. For this reason, the pixel electrode 21 cannot be formed up to the position where it overlaps with the TFT in plan view, and it has not been possible to increase the storage capacity and improve the aperture ratio by using the region where the TFT is formed.
In the liquid crystal display device disclosed in Patent Document 3, it is necessary to form the source electrode S and the drain electrode D after forming the pixel electrode 21, and then form the passivation film 19. For this reason, the pixel electrode 21 is exposed to an etching atmosphere after being formed at one end, so that the surface of the pixel electrode becomes rough. In addition, if the pixel electrode 21 that serves both as a display electrode and an auxiliary capacitor upper electrode is extended to the vicinity of the signal line, parasitic capacitance is generated in the signal line and the pixel electrode 21 to easily cause flicker, crosstalk, and the like. For this reason, a countermeasure method for preventing the pixel electrode 21 and the signal line from overlapping in plan view can be considered.
As a result, there is a problem that not only the auxiliary capacity but also the aperture ratio becomes small.

The present invention has been made to solve the above-described problems of the prior art, and is provided with a transparent lower electrode for auxiliary capacitance separate from the auxiliary capacitance wiring, and moreover than the conventional liquid crystal display device. In addition, an object of the present invention is to provide a liquid crystal display device in which an auxiliary capacitance can be formed large and an aperture ratio can be increased, and flicker, crosstalk, and the like hardly occur.

In order to achieve the above object, a liquid crystal display device of the present invention includes a first substrate and a second substrate sandwiching a liquid crystal layer, and the first insulating film and the first substrate are disposed on the liquid crystal layer side of the first substrate. A plurality of scanning lines and auxiliary capacitance lines formed between the substrates in parallel to each other; a plurality of signal lines formed on the surface of the first insulating film so as to intersect the scanning lines and auxiliary capacitance lines; A plurality of switching elements provided near intersections of the scanning lines and signal lines, a second insulating film covering the switching elements, the signal lines and the exposed surface of the first insulating film, and a plurality of switching elements. In a liquid crystal display device comprising a pixel electrode formed on the surface of the second insulating film for each region partitioned by the scanning line and the signal line, between the first substrate and the first insulating film Is a region partitioned by a plurality of the scanning lines and signal lines A storage capacitor lower electrode made of a transparent conductive material electrically connected to the storage capacitor line is formed, and the pixel electrode is connected to the electrode of the switching element through a contact hole formed in the second insulating film. And an auxiliary capacitance is formed between the auxiliary capacitance lower electrode and the pixel electrode.

The liquid crystal display device of the present invention includes a transparent auxiliary capacitor lower electrode that is separate from the auxiliary capacitor line. Since the auxiliary capacitor lower electrode is transparent, it is partitioned by a scanning line and a signal line. Each region can be formed with a wide area. Further, since the pixel electrode is electrically connected to the electrode of the switching element through the contact hole, the auxiliary capacitor lower electrode, the first insulating film, and the second
Thus, they are arranged to face each other through the insulating film. Therefore, according to the liquid crystal display device of the present invention, the pixel electrode operates as an auxiliary capacitor upper electrode, and the first insulating film and the second insulating film are provided as a dielectric between the pixel electrode and the auxiliary capacitor lower electrode. Therefore, it is possible to provide a liquid crystal display device in which an auxiliary capacitor having a large capacity is formed, the aperture ratio is large, and flicker, crosstalk, and the like hardly occur. In addition, in the liquid crystal display device of the present invention, the surface of the pixel electrode is rough because it is not exposed to the etching atmosphere after the pixel electrode is formed as in the invention disclosed in Patent Document 3 above. And a uniform quality liquid crystal display device can be obtained.

In the liquid crystal display device of the present invention, the electrode of the switching element extends to a position overlapping with the auxiliary capacitance line in plan view, and the contact hole has the auxiliary capacitance line, the auxiliary capacitance lower electrode, and the electrode in plan view. It is preferably formed at a position overlapping with the electrode of the switching element.

In general, the auxiliary capacitance line is formed at the same time as the scanning line, and thus is formed of an opaque metal material. Since the auxiliary capacitance line and the auxiliary capacitance lower electrode need only be electrically connected, the auxiliary capacitance line can be formed either above or below the auxiliary capacitance lower electrode. Furthermore, in the liquid crystal display panel of the present invention, the electrode of the switching element extends to a position overlapping the auxiliary capacitance line in plan view.
The contact hole for electrically connecting the pixel electrode and the switching element electrode, that is, the drain electrode when the switching element is a TFT, overlaps the auxiliary capacitance line, the auxiliary capacitance lower electrode, and the switching element electrode in plan view. It can be formed at the position to be. With such a configuration, the distance between the switching element and the auxiliary capacitance line can be shortened, and the pixel electrode and the switching can be switched in a narrow area range in which the electrode of the opaque switching element and the auxiliary capacitance line overlap. Since the electrical connection with the element can be ensured, the area of the opaque portion occupied in one subpixel can be reduced. Therefore, according to the liquid crystal display device of the present invention, since the area of the region that can be effectively used for transmissive display is relatively wide, the aperture ratio is large,
In addition, it is possible to obtain a liquid crystal display device in which flicker, crosstalk and the like are unlikely to occur.

In the liquid crystal display device of the present invention, an interlayer film made of a resin material is formed at a position overlapping the signal line of the second insulating film in plan view, and the pixel electrode is formed on the surface of the interlayer film in plan view. It is preferable to overlap with the signal line.

When the pixel electrode is formed so as to partially overlap with the signal line, the area of the portion that cannot be used for image display in one subpixel can be reduced, but the parasitic capacitance generated between the pixel electrode and the signal line is large. Become. This parasitic capacitance causes flicker and crosstalk. However,
In the liquid crystal display device of the present invention, an interlayer film made of a resin material is formed at a position overlapping the signal line of the second insulating film in plan view, and the pixel electrode overlaps with the signal line on the surface of the interlayer film in plan view. Thus, the distance between the pixel electrode and the signal line is increased. Therefore, according to the liquid crystal display device of the present invention, the area of a region that cannot be used for image display in one sub-pixel is reduced, and the parasitic capacitance generated between the pixel electrode and the signal line is reduced. ,
In addition, it is possible to obtain a liquid crystal display device that is less prone to flicker and crosstalk.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the embodiment and the drawings.
The embodiments described below are not intended to limit the present invention to those described herein, and the present invention has been variously modified without departing from the technical idea shown in the claims. It can be applied equally. In each drawing used for the description in this specification, each layer and each member are displayed in different scales so that each layer and each member can be recognized on the drawing. However, it is not necessarily displayed in proportion to the actual dimensions.

FIG. 1 is a plan view of one sub-pixel that is seen through the color filter substrate of the liquid crystal display device of the first embodiment. 2 is a cross-sectional view taken along line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a plan view of one sub-pixel represented by seeing through the color filter substrate of the liquid crystal display device of the second embodiment. FIG. 5 is a cross-sectional view taken along line VV in FIG.

[First Embodiment]
A liquid crystal display device 10A according to the first embodiment will be described with reference to FIGS. 1 to 3
The same reference numerals are given to the same components as those of the conventional liquid crystal display device 50 shown in FIGS. This liquid crystal display device 10A operates in a TN mode of a vertical electric field type. The array substrate AR of the liquid crystal display device 10A has a plurality of scanning lines made of a metal such as aluminum or molybdenum on the first transparent substrate 11 made of transparent insulating glass or the like on the side facing the liquid crystal LC. 12 are formed in parallel at equal intervals. The scanning line 12
In this, the formation position of the gate electrode G of the TFT is partially widened. Further, auxiliary capacitance lines 13 made of a metal such as aluminum or molybdenum are formed on the scanning line 12 side between adjacent scanning lines 12. As shown in FIG. 1, the auxiliary capacitance line 13 has a wide portion that overlaps a contact hole 20 described later in plan view.

As shown in FIG. 3, each region surrounded by the scanning line 12 and a signal line 18 to be described later is arranged so as not to overlap the scanning line 12 and the signal line 18 in plan view, An auxiliary capacitance lower electrode 15 made of a transparent conductive material such as electrically connected ITO (Indium Thin Oxide) or IZO (Indium Zinc Oxide) is formed.

Further, a transparent gate insulating film 16 made of silicon nitride, silicon oxide or the like is laminated so as to cover the scanning line 12, the auxiliary capacitance line 13, the auxiliary capacitance lower electrode 15, and the exposed portion of the first transparent substrate 11. . This gate insulating film 16 corresponds to the first insulating film of the present invention. A semiconductor layer 17 made of amorphous silicon, polycrystalline silicon, or the like is formed on the gate insulating film 16 where the gate electrode G is to be formed. A plurality of signal lines 18 made of a metal such as aluminum or molybdenum are formed on the gate insulating film 16 so as to intersect the scanning lines 12, and the source electrode S of the TFT extends from the signal line 18. The source electrode S is in partial contact with the surface of the semiconductor layer 17.

Further, a drain electrode D formed simultaneously with the same material as that of the signal line 18 and the source electrode S is provided on the gate insulating film 16, and the drain electrode D is disposed in proximity to the source electrode S to form the semiconductor layer 17. Partially touching. Further, as shown in FIG. 1, the drain electrode D extends to a portion corresponding to a contact hole 20 described later. A region surrounded by the scanning line 12 and the signal line 18 corresponds to one sub-pixel region. The gate electrode G, the gate insulating film 16, the semiconductor layer 17, the source electrode S, and the drain electrode D constitute a thin film transistor TFT serving as a switching element, and this TFT is formed in each subpixel.

Further, a transparent passivation film 19 made of, for example, silicon nitride or silicon oxide is laminated so as to cover the exposed portions of the signal line 18, the TFT, and the gate insulating film 16. This passivation film 19 corresponds to the second insulating film of the present invention. The passivation film 1
9, a contact hole 20 is formed at a position corresponding to the drain electrode D of the TFT. In each subpixel, a pixel electrode made of a transparent conductive material such as ITO or IZO so as to cover the inner surface of the contact hole 20, the surface of the passivation film 19, and the surface of the drain electrode D serving as an opening of the passivation film 19. 21 is formed. The pixel electrode 21 is formed so as to partially overlap the signal line 18 in plan view in order to increase the aperture ratio. Further, a first alignment film 22 made of polyimide, for example, is laminated on the surface of the pixel electrode 21 so as to cover all the pixels.

The color filter substrate CF is formed on the display area of the second transparent substrate 23 made of transparent insulating glass or the like and on the side facing the liquid crystal LC so as to correspond to each pixel. A striped color filter layer 24 composed of any one of red (R), green (G), and blue (B) is provided. A top coat layer 25 made of a transparent resin layer is formed on the surface of the color filter layer 24. A transparent conductive material such as ITO or IZO is formed on the surface of the top coat layer 25 over the entire surface of the color filter substrate CF. A common electrode 26 made of is laminated, and a second alignment film 27 made of polyimide, for example, is laminated on the surface of the common electrode 26. The light shielding member 2 is placed on the surface of the color filter substrate CF facing the liquid crystal LC at a position corresponding to the scanning line 12, the signal line 18 and the TFT of the array substrate AR.
8 is formed.

The array substrate AR and the color filter substrate CF thus formed are opposed to each other, and a sealing material is provided around both substrates to bond both substrates together.
TN liquid crystal display device 10A according to the first embodiment is obtained. A spacer (not shown) for holding the liquid crystal layer LC at a predetermined thickness is formed on the color filter substrate CF, and a first polarizing plate 29 is attached to the back surface of the array substrate AR, so that the color A second polarizing plate 30 is attached to the display surface side of the filter substrate CF. Also,
On the back surface of the first polarizing plate 29, a backlight device 31 having a well-known light source, a light guide plate, a diffusion sheet and the like (not shown) is disposed as in the case of the liquid crystal display device of the conventional example.

In the liquid crystal display device 10A of the first embodiment, as shown in FIG.
Is connected to the drain electrode D of the TFT through a contact hole 20 that penetrates the passivation film 19, so that the pixel electrode 21 can be formed so as to overlap the thin film transistor TFT in plan view. Therefore, as shown in FIG. 1, the pixel electrode 21 can be formed so as to occupy most of the region surrounded by the scanning line 12 and the signal line 18.
The aperture ratio can be increased.

The auxiliary capacitance lower electrode 15 can be formed as long as it does not overlap the scanning line 12 and the signal line 18 in a plan view. The auxiliary capacitance lower electrode 15 is a pixel except for a portion corresponding to the TFT. It is formed in substantially the same region as the electrode 21. Then, the liquid crystal display device 10A of the first embodiment.
, The auxiliary capacitor is formed by using the transparent auxiliary capacitor lower electrode 15 as a lower electrode, the transparent pixel electrode 21 as an auxiliary capacitor upper electrode, and the transparent gate insulating film 16 and the passivation film 19 as a dielectric. . The auxiliary capacitor holds an image signal even when the TFT is turned off, and since the area of the auxiliary capacitor forming area is large, the auxiliary capacitor can be increased, and flicker and crosstalk can be reduced. . Further, since the auxiliary capacitance forming region is transparent, the aperture ratio can be improved. Although the auxiliary capacitance lower electrode 15 is formed so as to cover the upper layer of the auxiliary capacitance line 13, the auxiliary capacitance lower electrode 15 only needs to be electrically coupled to the auxiliary capacitance line 13. The auxiliary capacitance line 13 may be formed on the surface of the lower electrode 15 for use.

[Second Embodiment]
A liquid crystal display device 10B according to a second embodiment will be described with reference to FIGS. 4 is a plan view of one sub-pixel corresponding to FIG. 1 of the liquid crystal display device 10A of the first embodiment, and FIG. 5 is a cross-sectional view corresponding to FIG. In the liquid crystal display device 10B of the second embodiment, the first
The cross-sectional view corresponding to FIG. 3 of the liquid crystal display device 10A of the embodiment is substantially the same, and is not shown. Also, the same reference is made to the same part as the liquid crystal display device 10A of the first embodiment. Reference numerals are assigned and detailed description thereof is omitted.

In the liquid crystal display device 10A of the first embodiment, the pixel electrode 21 is formed so as to partially overlap the signal line 18 in plan view in order to increase the aperture ratio. Parasitic capacitance is formed between the two, causing flicker and crosstalk. Therefore, in the liquid crystal display device 10B of the second embodiment, an interlayer film 32 made of a transparent resin material such as a photoresist is formed between the passivation film 19 and the pixel electrode 21 so as to overlap the signal line 18 in plan view. Is. By this interlayer film 32, the distance between the signal line 18 and the pixel electrode 21 can be increased. Therefore, even if the pixel electrode 21 is formed so as to partially overlap the signal line 18 in plan view, the parasitic capacitance formed between the signal line 18 and the pixel electrode 21 can be reduced, and flicker and Crosstalk can be reduced.

FIG. 3 is a plan view of one sub pixel that is seen through a color filter substrate of the liquid crystal display device of the first embodiment. It is sectional drawing of the II-II line of FIG. It is sectional drawing of the III-III line | wire of FIG. It is a top view for 1 sub-pixel represented through seeing a color filter substrate of a liquid crystal display of a 2nd embodiment. It is sectional drawing of the VV line of FIG. It is a top view for 1 sub pixel of the liquid crystal display device of the conventional TN mode. It is sectional drawing of the VII-VII line of FIG. It is sectional drawing of the VIII-VIII line of FIG. 9A is a schematic equivalent circuit diagram of one sub-pixel portion of the liquid crystal display device shown in FIG. 6, and FIG. 9B is a diagram showing voltage waveforms of each portion of one sub-pixel of the liquid crystal display device shown in FIG. . It is a schematic cross section of the array substrate of the liquid crystal display device of another conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10A, 10B ... Liquid crystal display device 11 ... 1st transparent substrate 12 ... Scanning line 13 ... Auxiliary capacity line 15, 51 ... Lower electrode for auxiliary capacity 16 ... Gate insulating film (1st insulating film) 17 ... Semiconductor layer 18 ... Signal line DESCRIPTION OF SYMBOLS 19 ... Passivation film | membrane (2nd insulating film) 20 ... Contact hole 21 ... Pixel electrode 22 ... 1st orientation film 23 ... 2nd transparent substrate 24 ... Color filter layer
DESCRIPTION OF SYMBOLS 25 ... Topcoat layer 26 ... Common electrode 27 ... 2nd alignment film 28 ... Light-shielding member 29 ... 1st polarizing plate 30 ... 2nd polarizing plate 31 ... Backlight apparatus 32, 34 ... Interlayer film LC ... Liquid crystal layer AR ... Array substrate CF: Color filter substrate

Claims (3)

A first substrate and a second substrate sandwiching a liquid crystal layer, and a plurality of scanning lines formed in parallel with each other between the first insulating film and the first substrate on the liquid crystal layer side of the first substrate And a plurality of signal lines formed on the surface of the first insulating film so as to intersect the scanning lines and the auxiliary capacitance lines, and in the vicinity of intersections of the plurality of scanning lines and the signal lines. The switching element, the switching element, the signal line, the second insulating film covering the exposed surface of the first insulating film, and the region divided by the plurality of scanning lines and signal lines. In a liquid crystal display device comprising a pixel electrode formed on the surface of two insulating films,
Between the first substrate and the first insulating film, an auxiliary made of a transparent conductive material electrically connected to the auxiliary capacitance line for each region partitioned by the plurality of scanning lines and signal lines. A lower electrode for capacitance is formed,
The pixel electrode is electrically connected to the electrode of the switching element through a contact hole formed in the second insulating film;
A liquid crystal display device, wherein an auxiliary capacitor is formed between the auxiliary capacitor lower electrode and the pixel electrode. The electrode of the switching element extends to a position overlapping the auxiliary capacitance line in plan view,
2. The liquid crystal display device according to claim 1, wherein the contact hole is formed at a position overlapping with the auxiliary capacitance line, the auxiliary capacitance lower electrode, and the electrode of the switching element in a plan view. An interlayer film made of a resin material is formed at a position overlapping the signal line of the second insulating film in plan view, and the pixel electrode overlaps the signal line on the surface of the interlayer film in plan view. The liquid crystal display device according to claim 1 or 2.

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