JP2009300648A - Liquid crystal display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display panel wherein a bubble is hardly produced, even if an impact test under low temperature environment is performed in the FFS mode liquid crystal display panel provided with an interlayer film. <P>SOLUTION: The liquid crystal display panel 10A includes an array substrate AR and a color filter substrate CF, disposed opposite to each other sandwiching a liquid crystal 35. The array substrate AR includes a lower electrode 19 formed on the surface of the interlayer film 18, made of a resin material and an upper electrode 22, formed on the surface of the lower electrode 19 via an inter-electrode insulating film 20 and having a plurality of slit-shaped apertures 24. In a contact part of a tip part of a columnar spacer 30 formed on the color filter substrate CF with the array substrate AR, apertures 31a and 31b are formed in the lower electrode 19 and the inter-electrode insulating film 20; the upper electrode 22 is formed directly on the surface of the interlayer film 18 in the apertures 31a and 31b; and the columnar spacer 30 is disposed so as to come in contact with the upper electrode 22 in the apertures 31a and 31b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a horizontal electric field type liquid crystal display panel, and in particular, includes a lower electrode and an upper electrode in which a plurality of slit-shaped openings are formed via an interelectrode insulating film on the surface of an interlayer film made of a resin material, and has low temperature impact characteristics. The present invention relates to an excellent lateral electric field liquid crystal display panel.

Liquid crystal display panels are characterized by their light weight, thinness, and low power consumption compared to CRTs (cathode ray tubes), and are therefore used in many electronic devices for display purposes. The liquid crystal display panel displays an image by changing the direction of liquid crystal molecules aligned in a predetermined direction by an electric field by rubbing the alignment film, thereby changing the amount of light transmitted or reflected.

As a method of applying an electric field to the liquid crystal of the liquid crystal display panel, there are a vertical electric field type and a horizontal electric field type. A vertical electric field type liquid crystal display panel applies a substantially vertical electric field to liquid crystal molecules by a pair of electrodes arranged with a liquid crystal in between. The vertical electric field type liquid crystal display panel includes a TN (Twisted Nematic) mode, a VA (Vertical Alignment) mode, an M
A VA (Multi-domain Vertical Alignment) mode or the like is known. A horizontal electric field type liquid crystal display panel is provided with a pair of electrodes insulated from each other on one inner surface of a pair of substrates disposed with a liquid crystal in between, and an electric field in a substantially horizontal direction is applied to liquid crystal molecules. To do.
In this horizontal electric field type liquid crystal display panel, a pair of electrodes do not overlap in plan view.
-Plane Switching) and overlapping FFS (Fringe Field Switching) are known.

Among these, in the FFS mode liquid crystal display panel, a pair of electrodes consisting of an upper electrode and a lower electrode are arranged in different layers via an interelectrode insulating film, and a slit-like opening is formed in the upper electrode.
A substantially horizontal electric field passing through the slit-shaped opening is applied to the liquid crystal. In recent years, the FFS mode liquid crystal display panel has been widely used because it has a high aperture ratio and can provide a wide viewing angle and an improved image contrast.

Incidentally, columnar spacers are used in the liquid crystal display panel in order to make the cell gap (the thickness of the liquid crystal) constant. Such columnar spacers have good cell gap maintenance characteristics when the density of the columnar spacers arranged in the display area is increased, but there is a problem that bubbles are generated in a low temperature impact test. The low temperature impact test is performed as a guarantee of the product quality of the liquid crystal display panel in a low temperature environment, and the liquid crystal display panel is held in a low temperature environment of about −20 ° C., and then the impact is applied to the display surface. Is used to check the degree of bubble generation. Therefore, in the invention disclosed in the following Patent Document 1, the arrangement density of the columnar spacers is optimized by changing the diameter of the columnar spacers, and the generation of bubbles is suppressed during the low temperature impact test.
JP 2006-243614 A JP 2008-70688 A JP 2005-338264 A

In recent years, as a horizontal electric field type liquid crystal display panel aiming at higher aperture ratio, higher brightness, and higher viewing angle, a lower electrode and an interelectrode insulating film such as silicon nitride are formed on an interlayer film made of a transparent resin. An FFS mode liquid crystal display panel in which an upper electrode having a plurality of slit-shaped openings is formed has been developed (see Patent Documents 2 and 3). However, according to experiments by the inventors, it has been found that in the FFS mode liquid crystal display panel provided with such an interlayer film, bubbles are easily generated in a low-temperature impact test. The bubble generation phenomenon in the FFS mode liquid crystal display panel having such an interlayer film will be described with reference to FIG.

6A to 6D are schematic cross-sectional views for sequentially explaining the principle of bubble generation during a low temperature impact test.

In FIG. 6, only the part necessary for the explanation of the bubble generation principle is shown, and the detailed configuration of the other part is omitted. That is, the array substrate AR of the liquid crystal display panel 50
An interlayer film 52 made of a photosensitive resin or the like is formed on the transparent substrate 51, and an interelectrode insulating film 53 made of silicon nitride or the like is formed on the surface thereof. Originally, a lower electrode and an upper electrode are formed on both sides of the interelectrode insulating film 53, respectively, but the lower electrode and the upper electrode are thinner than the interelectrode insulating film 53, and moreover than the interelectrode insulating film. Is also soft and can be substantially ignored when considering impact properties. The color filter substrate CF has a color filter layer 55 formed on the surface of the transparent substrate 54. A columnar spacer 56 made of a photosensitive resin or the like is formed on the surface of the color filter substrate CF, and the columnar spacer 56 is in contact with the surface of the array substrate AR.

When an external pressure F is applied from the outer surface of the liquid crystal display panel 50 (see FIG. 6A), the external pressure is transmitted from the color filter substrate CF to the array substrate AR through the columnar spacer 56, and the liquid crystal display panel 50 is bent (FIG. 6B). reference). When the external pressure F is removed in this state, the liquid crystal display panel 50 tries to restore the original state as shown in FIG. 6C. Since the interelectrode insulating film 53 made of silicon nitride or the like is hard, its restoration speed V3 is faster than the restoration speed V4 of the liquid crystal 57.
In addition, the liquid crystal display panel 50 is bent beyond its original position as shown in FIG.
Restore to the original position as shown in. Also when restoring from the original position shown in FIG. 6C to the original position shown in FIG. 6D, the restoration speed V3 of the interelectrode insulating film 53 is the restoration speed V of the liquid crystal 57.
Faster than 4. Therefore, inside the liquid crystal 57, a difference occurs in the pressure distribution, and a part of the liquid crystal 57 has a negative pressure. Therefore, as shown in FIG. 6D, bubbles 58 are generated. This bubble 58 does not disappear easily under a low temperature environment, for example, a low temperature environment of about −20 ° C.
It will interfere with the display.

In the bubble generation phenomenon, most of the external force transmitted to the array substrate AR through the columnar spacer 56 is received by the hard interelectrode insulating film 53, and the interlayer film 52 made of a soft resin layer almost receives the external force. It seems to have occurred because it could not be absorbed. Therefore, even if the countermeasure for the low temperature impact test of optimizing the columnar spacer density as in the invention disclosed in Patent Document 1 is applied to the FFS mode liquid crystal display panel having an interlayer film made of a resin layer, the columnar spacer Since air bubbles are generated at the location where the water is present, it cannot be an effective measure.

The present invention has been made to solve the problems of the FFS mode liquid crystal display panel having the interlayer film as described above. That is, an object of the present invention is to provide an FFS mode liquid crystal display panel having an interlayer film, in which bubbles are not easily generated even when an impact test is performed in a low temperature environment.

In order to achieve the above object, a liquid crystal display panel of the present invention has first and second substrates that are opposed to each other with a liquid crystal interposed therebetween, and the first substrate is a surface of an interlayer film made of a resin material. A lower electrode formed on the surface of the lower electrode, and an upper electrode having a plurality of slit-shaped openings formed on the surface of the lower electrode through an interelectrode insulating film, and a columnar spacer on one of the first and second substrates In the liquid crystal display panel in which the tip of the columnar spacer is in contact with the surface of another substrate, the contact portion between the first substrate and the columnar spacer is one of the lower electrode and the upper electrode. And an opening is formed in the interelectrode insulating film, the other of the lower electrode and the upper electrode is directly formed on the surface of the interlayer film in the opening, and the columnar spacer is formed in the opening in the lower electrode. And in contact with the other of the upper electrodes Characterized in that it is located

The liquid crystal display panel of the present invention has first and second substrates disposed opposite to each other with a liquid crystal sandwiched between them, and the first substrate includes a lower electrode formed on the surface of an interlayer film made of a resin material. And an upper electrode having a plurality of slit-like openings formed on the surface of the lower electrode through an interelectrode insulating film. With this configuration, the liquid crystal display panel of the present invention operates in the FFS mode. In addition, although an inorganic insulating film such as silicon oxide or silicon nitride is used as the interelectrode insulating film, silicon nitride is desirable from the viewpoint of insulation. Moreover, as an interlayer film made of a resin material, a photosensitive or non-photosensitive resin material having good transparency and excellent electrical insulation can be appropriately selected and used. Furthermore, as the lower electrode and the upper electrode, ITO (Indium Tin Oxide) to IZO (
Transparent conductive materials such as Indium Zinc Oxide) are used.

In the liquid crystal display panel of the present invention, an opening is formed in one of the lower electrode and the upper electrode and the interelectrode insulating film at the contact portion between the first substrate and the columnar spacer, The other of the lower electrode and the upper electrode is directly formed on the surface of the interlayer film, and the columnar spacer is disposed in contact with the other of the lower electrode and the upper electrode in the opening.
That is, in the liquid crystal display panel of the present invention, it is essential that an opening be formed in the interelectrode insulating film, and an opening is formed in one of the lower electrode and the upper electrode. Of these, the electrode having no opening is directly formed on the surface of the interlayer film. The columnar spacer is in contact with the lower electrode or the upper electrode directly formed on the surface of the interlayer film.
Then, the columnar spacer is not in contact with the interelectrode insulating film, and is in contact with the interlayer film via the lower electrode or the upper electrode directly formed on the surface of the interlayer film.

In general, the thickness of the lower electrode and the upper electrode is thinner than the interelectrode insulating film formed between the lower electrode and the upper electrode, and the hardness of the lower electrode and the upper electrode is softer than the interelectrode insulating film. Therefore, when an external force is applied from the surface of the liquid crystal display panel, the external force is transmitted to the interlayer film of the first substrate through the second substrate, the columnar spacer, the lower electrode, or the upper electrode. Therefore, according to the liquid crystal display panel of the present invention, even if an external force is applied from the surface of the liquid crystal display panel, the external force is absorbed by the interlayer film made of a resin material. Therefore, bubbles are hardly generated, and the liquid crystal display panel is excellent in low temperature impact resistance.

In the liquid crystal display panel of the present invention, the step of forming the opening in the interelectrode insulating film can be simultaneously formed in the process of forming various contact holes in the interelectrode insulating film, and the opening is formed in the lower electrode or the upper electrode. The process can be simultaneously formed in the patterning process of the lower electrode or the upper electrode. Therefore, in order to manufacture the liquid crystal display panel of the present invention, it is not necessary to increase the number of special processes, and the liquid crystal display panel of the present invention can be manufactured by a conventional manufacturing process.

In the liquid crystal display panel of the present invention, it is preferable that the opening is equal to or larger than the diameter of the columnar spacer.

In the liquid crystal display panel of the present invention, since the opening is the same as or larger than the diameter of the columnar spacer, the columnar spacer does not come into contact with the surface of the interelectrode insulating film. Therefore, according to the liquid crystal display panel of the present invention, when an external force is applied from the surface of the liquid crystal display panel, the external force is efficiently absorbed by the interlayer film made of a resin material, so that bubbles are less likely to be generated. A liquid crystal display panel with superior low-temperature impact resistance is obtained. In addition, since the alignment of the opening on the first substrate and the columnar spacer is facilitated, the manufacture of the liquid crystal display panel of the present invention is facilitated.

In the liquid crystal display panel of the present invention, it is desirable that the diameter of one of the lower electrode and the upper electrode is larger than the diameter of the opening of the interelectrode insulating film.

When the diameter of one opening of the lower electrode and the upper electrode is larger than the diameter of the opening of the interelectrode insulating film,
Since the distance between the other one of the lower electrode and the upper electrode directly formed on the surface of the interlayer film in the opening is increased, an electrical short circuit between the lower electrode and the upper electrode is less likely to occur, and It becomes a high-performance liquid crystal display panel.

In the liquid crystal display panel of the present invention, it is preferable that the opening and the columnar spacer are formed at a position overlapping the switching element formed on the first substrate in plan view.

The switching element formed on the first substrate has a portion made of a semiconductor material, a metal material, or the like, which is a light-impermeable material, and further occupies a large area in plan view for each subpixel. In addition, the columnar spacer has a first substrate and a second substrate in plan view in order to increase the aperture ratio.
It is formed in a light-impermeable portion formed on the substrate. According to the liquid crystal display panel of the present invention, the openings and the columnar spacers are formed at positions overlapping with the switching elements formed on the first substrate in plan view, so that the columnar spacers are formed more than the other portions. The decrease in the aperture ratio due to the presence of the spacer is reduced. As a switching element that can be used in the liquid crystal display panel of the present invention, a thin film transistor using amorphous silicon as a semiconductor material (
TFT: Thin Film Transistor, TFT using polysilicon, Low temperature polysilicon (
LTPS: Low Temperature Poly Silicon (TFT), thin film diode TFD (Thin Film)
Diode) or the like can be used.

In the liquid crystal display panel of the present invention, it is preferable that one opening and one columnar spacer are formed for each pixel.

Although the resistance to external force applied to the surface increases in proportion to the arrangement density of the columnar spacers,
The low-temperature impact resistance characteristics deteriorate, and the adverse effect on the alignment of liquid crystal molecules around the columnar spacer due to the presence of the columnar spacer also increases. However, according to the liquid crystal display panel of the present invention, since one columnar spacer is formed for each pixel, the liquid crystal can be harmonized with the resistance to external force applied to the surface, the low-temperature impact resistance characteristics, and the display image quality. A display panel is obtained.

Hereinafter, the best embodiment of the present invention will be described with reference to the drawings. However, the following embodiment shows an example for embodying the technical idea of the present invention, and is not intended to specify the present invention in this example, and is included in the scope of the claims. Other embodiments are equally applicable. Furthermore, in each drawing used for the description in this specification, each layer and each member are displayed with 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 schematic plan view of three sub-pixels (one pixel) seen through the color filter substrate of the FFS mode liquid crystal display panel of the first embodiment. FIG. 2 is a sectional view taken along line II-II in FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 4A to 4D are schematic views for explaining the behavior when the liquid crystal display panel of this embodiment is subjected to a low temperature impact. FIG. 5 is a cross-sectional view corresponding to FIG. 2 of the FFS mode liquid crystal display panel of the second embodiment of the present invention.

[First Embodiment]
A liquid crystal display panel 10A according to the first embodiment will be described in the order of manufacturing steps with reference to FIGS.
The array substrate AR in the FFS mode liquid crystal display panel 10A of the first embodiment is:
First, a conductive layer such as aluminum or an aluminum alloy is formed over the entire surface of the transparent substrate 11 such as a glass substrate. Thereafter, a plurality of scanning lines 12 are formed in the display region so as to be parallel to each other by a well-known photolithography method and etching method, and common wiring (not shown) is formed in the peripheral portion of the display region. Common wiring is driver I
The wiring is formed thicker than other wirings so as to surround the outer periphery of the display area except for a part of the periphery where C and various terminals are arranged.

Next, the entire surface is covered with a gate insulating film 13 made of a silicon nitride layer or a silicon oxide layer. Thereafter, for example, amorphous silicon (hereinafter referred to as “a-Si”) is formed by a CVD method.
That's it. ) Layer is coated over the entire surface of the gate insulating film 13, and then the semiconductor layer 14 made of an a-Si layer in the TFT formation region by the same photolithography method and etching method.
Form. The region of the scanning line 12 at the position where the semiconductor layer 14 is formed forms the gate electrode G of the TFT.

Next, a conductive layer made of aluminum or an aluminum alloy is coated over the entire surface of the transparent substrate 11 on which the semiconductor layer 14 is formed. Further, the signal line 15 including the source electrode S and the drain electrode D are formed so that the conductive layer intersects the scanning line 12 by photolithography and etching. Note that both the source electrode S portion and the drain electrode D portion of the signal line 15 partially overlap the surface of the semiconductor layer 14. The TFT having the gate electrode G, the source electrode S, and the drain electrode D formed as described above corresponds to the switching element of the present invention. This TFT is formed for each sub-pixel region defined by the scanning line 12 and the signal line 15 in the display region. Thereafter, a passivation film 17 is coated on the entire surface of the transparent substrate 11 obtained in the above process. As the passivation film 17, a silicon nitride layer or a silicon oxide layer can be used, but a silicon nitride layer is more desirable from the viewpoint of insulation.

Next, a film made of, for example, a photosensitive resin is formed on the entire surface of the transparent substrate 11, and exposure and development are performed, so that an opening is formed at a planned formation position of the contact hole 21 on each drain electrode D. An interlayer film 18 is formed. Next, SF _{6 is used} as an etching gas.
The passivation film 17 exposed at the position where the contact hole 21 is to be formed is removed by plasma etching using a fluorine-based gas typified by CF ₄ , and the drain electrode D
To expose a part of

Next, a lower transparent conductive layer made of ITO or IZO is laminated, and a lower electrode 19 is formed in a predetermined pattern for each sub-pixel region by a photolithography method and an etching method, and a columnar spacer 30 is disposed. Opening 31a in the lower electrode 19 in the region (see FIG. 2)
Form. In addition, the opening 3 formed in the lower electrode 19 in the region where the columnar spacer 30 is disposed.
1a is formed for every three sub-pixels (one pixel). Thus, the lower electrode 1
9 can be formed simultaneously with the patterning of the lower electrode 19. Further, the lower electrode 19 is electrically connected to the drain electrode D through the contact hole 21 for every sub-pixel, and operates as a pixel electrode.

Further, an interelectrode insulating film 20 made of a silicon nitride layer or a silicon oxide layer is formed to a predetermined thickness over the entire surface of the transparent substrate 11 on which the lower electrode 19 is formed. The interelectrode insulating film 20 is
In order not to make the surface of the interlayer film 18 and the lower electrode 19 rough, the film is formed under conditions that are milder than the formation conditions of the gate insulating film 13 and the passivation film 17, so-called low-temperature film formation conditions.
Thereafter, the inter-electrode insulating film 20 is subjected to plasma etching, whereby the columnar spacers 30 are formed.
In addition, an opening 31b is formed in the interelectrode insulating film 20 in the region where the electrode is disposed, and for example, the interelectrode insulating film 20 at a position where a contact hole is planned to be formed in the peripheral portion of the display region is also appropriately removed. Thus, the opening 31b formed in the interelectrode insulating film 20 can be formed at the same time when a contact hole is formed in the interelectrode insulating film 20. At this time, the diameter of the opening 31b of the interelectrode insulating film 20 in the region where the columnar spacer 30 is disposed is set so that the lower electrode is formed in order to prevent an electrical short circuit between the upper electrode 22 and the lower electrode 19 formed thereafter. 19 is smaller than the diameter of the opening 31a formed in 19 and is equal to or larger than the diameter of the columnar spacer 30 to be used.

Next, a transparent conductive material made of ITO or IZO is coated on the entire surface of the transparent substrate 11. Then, the transparent conductive material covers the surface of the interelectrode insulating film 20 on the contact hole 21 side, and is electrically insulated from the lower electrode 19 in the opening 31a formed in the lower electrode 19, The surface of the interlayer film 18 is covered, and further, the periphery of the display area is electrically connected to the common wiring. Next, a plurality of slit-like openings 24 for generating a fringe field effect are formed by photolithography and etching. The upper electrode 22 thus formed operates as a common electrode. Thereafter, an alignment film (not shown) is provided on the entire surface on the upper electrode 22 side, thereby completing the array substrate AR for the liquid crystal display panel 10A of the first embodiment.

The color filter substrate CF facing the array substrate AR may be substantially the same as a color filter substrate for a conventional FFS mode liquid crystal display panel. That is, in the color filter substrate CF, the color filter layer 33 of each color is formed on the surface of the transparent substrate 32 made of a glass substrate or the like at a position facing the lower electrode 19 functioning as each pixel electrode, and the color filter A topcoat layer 34 and an alignment film (not shown) are sequentially formed on the surface of the layer 33. A light shielding member (not shown) is formed between the color filter layer 33 of the color filter substrate CF and the transparent substrate 32 at positions facing the scanning lines 12, the signal lines 15, and the TFTs of the array substrate AR. ing. A columnar spacer 30 made of a photosensitive resin or the like is formed at a position facing the opening 31b formed in the inter-electrode insulating film 20 of the array substrate AR in the light shielding member at a position facing the TFT. Next, the array substrate AR and the color filter substrate CF described above are bonded to each other so as to face each other so that the tip of the columnar spacer 30 is disposed in the opening 31b formed in the insulating layer 20 of the array substrate AR. The liquid crystal display panel 10A of the first embodiment is obtained by enclosing the liquid crystal 35 inside.

The state during the low-temperature impact test of the liquid crystal display panel 10A of the first embodiment is shown in FIGS.
A description will be given using D. 4A to 4D, as in the case of the conventional example described in FIGS. 6A to 6D, only the portions necessary for explaining the bubble generation principle are described, and the detailed configuration of the other portions is as follows. It is omitted. 4A to 4D, as the array substrate AR of the liquid crystal display panel 10A of the first embodiment, an interlayer film 18 made of a photosensitive resin or the like formed on the transparent substrate 11 and formed on the surface thereof. Only the interelectrode insulating film 20 made of silicon nitride or the like is shown. Further, as the color filter substrate CF of the liquid crystal display panel 10A of the first embodiment, only the color filter layer 33 formed on the transparent substrate 32 and the columnar spacer 30 made of a photosensitive resin or the like are shown. Since the lower electrode 19 and the upper electrode 22 are softer than the interelectrode insulating film 20, the columnar spacers 30 formed on the color filter substrate CF are insulated between the electrodes of the array substrate AR when considering impact characteristics. Openings 31b formed in the film 32
It can be regarded as being in contact with the interlayer film 18 equivalently.

Here, when an external pressure F is applied from the outer surface of the liquid crystal display panel 10A (see FIG. 4A), the external pressure F is transmitted from the color filter substrate CF to the array substrate AR via the columnar spacers 30,
The liquid crystal display panel 10A bends (see FIG. 4B). If the external pressure F is removed in this state,
As shown in FIG. 4C, the liquid crystal display panel 10A attempts to restore the original state. The columnar spacer 30 is not in contact with the interelectrode insulating film 20 and is in equivalent contact with the interlayer film 18. Since the interlayer film 18 is softer than the interelectrode insulating film 20, the restoration speed V1 of the interlayer film 18 is
Although it is faster than the restoration speed V2 of the liquid crystal 35, the difference in the restoration speed is smaller than when the columnar spacer 30 is in direct contact with the interelectrode insulating film 20. In addition, the liquid crystal display panel 10A is shown in FIG.
After bending beyond the original position as shown in C, the original position is restored as shown in FIG. 4D. As described above, when restoring from the original position shown in FIG. 4C to the original position shown in FIG. 4D, the restoration speed V1 of the interlayer film 18 is faster than the restoration speed V2 of the liquid crystal 35. The difference is small. Therefore, even if a difference occurs in the pressure distribution inside the liquid crystal 35 and a partial negative pressure is generated, the generation of bubbles is suppressed because the negative pressure is small. Therefore, according to the liquid crystal display panel 10A of the first embodiment, even if an impact test is performed in a low temperature environment, the liquid crystal display panel is less likely to generate bubbles.

[Second Embodiment]
The configuration of the liquid crystal display panel 10B of the second embodiment will be described with reference to FIG. In the liquid crystal display panel 10B according to the second embodiment, the opening 31b is formed in the interelectrode insulating film 20, and the lower electrode 19 and the upper electrode 22 are the portions where the opening 31b is formed in the interelectrode insulating film 20. The point of being electrically insulated is the same as that of the liquid crystal display panel 10A of the first embodiment.
However, in the liquid crystal display panel 10B of the second embodiment, the opening 31c is formed in the upper electrode 22, and the lower electrode 19 is formed so as to continuously cover the interlayer film 18. The configuration is opposite to that of the liquid crystal display panel 10A of the embodiment. Note that FIG.
In the liquid crystal display panel 10B of the second embodiment shown in FIG. 2, the same reference numerals are given to the same components as those of the liquid crystal display panel 10A of the first embodiment, and detailed description thereof is omitted.

Also in the liquid crystal display panel 10B of the second embodiment, the columnar spacers 30 are not in contact with the interelectrode insulating film 20 and are in contact with the interlayer film 18 equivalently. The same effect as that of the liquid crystal display panel 10A of the embodiment can be obtained.

In the liquid crystal display panels 10A and 10B of the first and second embodiments described above, the lower electrode 19 operates as a pixel electrode and the upper electrode 22 operates as a common electrode. The electrode 19 may be a common electrode, and the upper electrode 22 may be a pixel electrode. Furthermore, the liquid crystal display panel 10 of the first and second embodiments described above.
In A and 10B, an example in which an a-Si TFT is formed as a switching element is shown, but not limited to this, a p-Si TFT, LTPS, TFD, or the like can also be used.

Further, in the liquid crystal display panels 10A and 10B of the first and second embodiments described above, an example in which the columnar spacer 30 is formed at a position corresponding to the TFT as a switching element is shown. However, since the aperture ratio does not decrease if the columnar spacer is formed at a position overlapping with the light shielding region in plan view, the columnar spacer may be formed at a position overlapping with the scanning line 12 or the signal line 15 in plan view. Furthermore, in the liquid crystal display panels 10A and 10B of the first and second embodiments described above, an example in which one columnar spacer 30 is formed for each pixel (for example, three sub-pixels) has been shown. The columnar spacers may be arranged at a higher density in order to strengthen the resistance. However, the resistance to external force applied to the surface increases in proportion to the arrangement density of the columnar spacers, but the low-temperature impact resistance deteriorates and the presence of the columnar spacers adversely affects the alignment of liquid crystal molecules around the columnar spacers. Also grows. For this reason, it is preferable that one pixel is formed for each pixel (for example, three sub-pixels) so that the resistance against external force applied to the surface, the low-temperature impact resistance characteristics, and the display image quality can be harmonized.

FIG. 3 is a schematic plan view of three sub-pixels (one pixel) represented by seeing through the color filter substrate of the FFS mode liquid crystal display panel of the first embodiment. It is sectional drawing along the II-II line of FIG. It is sectional drawing along the III-III line of FIG. 4A to 4D are schematic views for explaining the behavior when the liquid crystal display panel of the first embodiment is subjected to a low temperature impact. It is sectional drawing corresponding to FIG. 2 of the liquid crystal display panel of the FFS mode of the 2nd Embodiment of this invention. 6A to 6D are schematic views for explaining the behavior when a conventional liquid crystal display panel is subjected to a low temperature impact.

Explanation of symbols

10A, 10B: Liquid crystal display panel 11: Transparent substrate 12: Scanning line 13: Gate insulating film 14: Semiconductor layer 15: Signal line 17: Passivation film 18: Interlayer film 19: Lower electrode 20: Interelectrode insulating film 21: Contact hole 22: Upper electrode 24: Slit-shaped opening 30: Columnar spacer 31a: Opening of lower electrode 31b: Opening of insulating film between electrodes 31
c: Opening of upper electrode 32: Transparent substrate 33: Color filter layer 34: Overcoat layer 35: Liquid crystal AR: Array substrate CF: Color filter substrate

Claims (5)

The first and second substrates are disposed opposite to each other with a liquid crystal sandwiched between them. The first substrate includes a lower electrode formed on the surface of an interlayer film made of a resin material, and an electrode on the surface of the lower electrode. An upper electrode having a plurality of slit-shaped openings formed through an inter-layer insulating film, and a columnar spacer is formed on one of the first and second substrates, and the tip of the columnar spacer is attached to another substrate In the liquid crystal display panel in contact with the surface,
In the contact portion between the first substrate and the columnar spacer, an opening is formed in one of the lower electrode and the upper electrode and the inter-electrode insulating film, and the surface of the interlayer film in the opening is formed on the surface of the interlayer film. The other of the lower electrode and the upper electrode is directly formed, and the columnar spacer is disposed in contact with the other of the lower electrode and the upper electrode in the opening. The liquid crystal display panel according to claim 1, wherein the opening is equal to or larger than a diameter of the columnar spacer. The liquid crystal display panel according to claim 1, wherein a diameter of one opening of the lower electrode and the upper electrode is larger than a diameter of the opening of the interelectrode insulating film. The liquid crystal display panel according to claim 1, wherein the opening and the columnar spacer are formed at a position overlapping with a switching element formed on the first substrate in a plan view. The liquid crystal display panel according to claim 1, wherein one opening and one columnar spacer are formed for each pixel.

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