JP5323329B2 - Liquid crystal display - Google Patents

Description

  The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device having an alignment film and having a uniform thickness of liquid crystal material by columnar spacers provided on a counter substrate and a pedestal provided on a TFT substrate. It is related to effective technology when applied.

  Conventionally, liquid crystal display devices include active matrix liquid crystal display devices in which active elements and pixel electrodes are arranged in a matrix in a display area. Among the active matrix type liquid crystal display panels, active matrix type TFT liquid crystal display devices using TFT elements as the active elements include, for example, liquid crystal televisions, liquid crystal displays for PCs, and liquid crystal displays for portable electronic devices. It is used.

  In the liquid crystal display panel used in the active matrix TFT liquid crystal display device, a liquid crystal material is sandwiched (encapsulated) between two substrates, and one of the two substrates is mainly a TFT substrate. The other substrate is mainly called a counter substrate.

  The TFT substrate is formed on the surface of a first insulating substrate such as a glass substrate, for example, a plurality of scanning signal lines, a plurality of video signal lines, a plurality of TFT elements (active elements), and a plurality of pixel electrodes. , A substrate on which a first alignment film and the like are arranged. The counter substrate is formed on the surface of a second insulating substrate such as a glass substrate, for example, a light-shielding film (generally called a black matrix) that divides a display region into pixel unit regions, a color filter, and a second filter. A substrate on which an alignment film or the like is disposed. Note that a counter electrode (also referred to as a common electrode) that is paired with the pixel electrode may be provided on the TFT substrate, or may be provided on the counter substrate.

  In recent years, liquid crystal televisions and liquid crystal displays for PCs have been increased in screen size, and the TFT substrate and the counter substrate have increased in area. For this reason, for example, the TFT substrate and the counter substrate are easily bent, and the thickness of the liquid crystal material (also referred to as a cell gap) at each point in the display region is likely to be uneven. Therefore, in recent large-sized liquid crystal display panels, in order to make the thickness of the liquid crystal material uniform at each point of the display region, for example, a method of providing a frustoconical or columnar spacer on the counter substrate has been proposed ( For example, see Patent Document 1 and Patent Document 2.)

When the spacer is provided on the counter substrate, the alignment film on the counter substrate side is disposed (formed) on the surface on which the spacer is provided, and the alignment film is also formed on the top of the spacer. Is formed. However, if there is an alignment film on the top of the spacer, for example, the alignment film on the top of the spacer peels off due to friction with the TFT substrate, and becomes a foreign substance in the liquid crystal material, resulting in a deterioration in display quality. Is likely to occur. As a method for avoiding such a problem, for example, a method has been proposed in which the thickness of the alignment film on the top of the spacer is substantially 0 μm by leveling (see, for example, Patent Document 3).
JP 2005-242297 A JP 2005-316375 A JP 2000-267114 A

  By the way, in the liquid crystal display panel, when the spacer is disposed on the counter substrate, for example, the spacer includes a region intersecting the video signal line and the TFT element in the scanning signal line of the TFT substrate. In some cases, it is arranged at a position facing a region other than the region that has been set. At this time, a projecting pedestal for receiving the spacer is provided at a position facing the spacer on the TFT substrate.

  The base of the TFT substrate is provided, for example, by forming a conductive film made of the same material as that of the video signal line on the scanning signal line, and has a substantially flat three-dimensional shape at the top.

  Further, since the alignment film of the TFT substrate is disposed (formed) on the surface provided with the pedestal, in the conventional liquid crystal display panel, the alignment film is also formed on the top of the pedestal. Therefore, in the conventional liquid crystal display panel, for example, the alignment film on the top of the pedestal peels off due to friction with the top of the spacer, and becomes a foreign substance in the liquid crystal material, resulting in a problem that display quality is deteriorated. Cheap.

  Further, since the height of the pedestal of the TFT substrate is sufficiently lower than the height of the spacer of the counter substrate, for example, the thickness of the alignment film on the top of the pedestal by the method described in Patent Document 3 is used. There is also a problem that it is very difficult to make the thickness substantially 0 μm.

  An object of the present invention is to provide a technique capable of preventing peeling of an alignment film around a base of a TFT substrate, for example, in a liquid crystal display panel.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  The outline of typical inventions among the inventions disclosed in the present application will be described as follows.

  (1) A liquid crystal display panel in which a liquid crystal material is sealed between a first substrate and a second substrate is included, and the first substrate is a first insulating substrate and a surface of the first insulating substrate. A plurality of scanning signal lines, a plurality of video signal lines, a plurality of TFT elements, and a plurality of pixel electrodes, and the scanning signal lines of the first insulating substrate, the video signal lines, The TFT element, and a first alignment film provided on an uppermost layer on the surface on which the pixel electrode is disposed, wherein the second substrate is a second insulating substrate and the second insulating substrate A plurality of substantially columnar spacers disposed on the surface of the second insulating substrate, and a second alignment film provided on the uppermost layer of the surface of the second insulating substrate on which the spacers are disposed. The surface of the first substrate on which the first alignment film is disposed is the space of the second substrate. And the top of the first substrate has a height from the surface on which the first alignment film is disposed, and the second substrate has a height from the surface on which the first alignment film is disposed. The distance between the outer periphery of the top and the surface of the first insulating substrate when viewed in a plane is lower than the height of the spacer from the surface on which the second alignment film is disposed. A liquid crystal display device that changes once or more during one round of the outer periphery of the top of the pedestal.

  (2) In the liquid crystal display device according to (1), the spacer of the second substrate includes a region of the scanning signal line of the first substrate intersecting with the video signal line and the TFT element. A liquid crystal display device arranged at a position facing a region other than the arranged region.

  (3) In the liquid crystal display device according to (1) or (2), each of the scanning signal is provided at a position of the surface of the first insulating substrate facing the spacer of the second substrate. An island-shaped film independent of any of the line, the video signal line, the TFT element, and the pixel electrode is disposed, and the island-shaped film has a part of the outer periphery when viewed in a plane. Liquid crystal display device which is receding to the center side of the film.

  (4) The liquid crystal display device according to (3), wherein the island-shaped film is a conductive film made of the same material as the video signal line.

  (5) In the liquid crystal display device according to (1) or (2), the scanning signal is provided at a position of the surface of the first insulating substrate facing the spacer of the second substrate. An island-shaped first film and a second film independent of any of a line, the video signal line, the TFT element, and the pixel electrode are disposed, and the first film is viewed in a plan view. The liquid crystal display device has a region overlapping with the second film and a region not overlapping with the second film, and the second film includes a region overlapping with the first film and a region not overlapping when viewed in a plane.

  (6) In the liquid crystal display device according to (5), a region of the second film that overlaps the first film runs on the first film as viewed from the first insulating substrate. Liquid crystal display device.

  (7) In the liquid crystal display device according to (6), the first film has a portion of a portion of the outer periphery of the first film that does not overlap with the second film when viewed in a plane. A liquid crystal display that recedes to the center.

  (8) In the liquid crystal display device according to any one of (5) to (7), the first film is a semiconductor film made of the same material as the semiconductor layer of the TFT element, and the second film is A liquid crystal display device which is a conductive film made of the same material as the video signal line.

  According to the liquid crystal display device of the present invention, it is possible to prevent peeling of the alignment film around the base of the first substrate (TFT substrate).

Hereinafter, the present invention will be described in detail together with embodiments (examples) with reference to the drawings.
In all the drawings for explaining the embodiments, parts having the same function are given the same reference numerals and their repeated explanation is omitted.

1A and 1B and FIGS. 2A to 2D illustrate an example of a schematic configuration of a liquid crystal display panel according to the present invention and problems in a conventional liquid crystal display panel. It is a schematic diagram for doing.
FIG. 1A is a schematic plan view showing an example of a schematic configuration of a liquid crystal display panel according to the present invention. FIG. 1B is a schematic cross-sectional view of the liquid crystal display panel taken along line AA ′ in FIG.
FIG. 2A is a schematic plan view showing an example of the configuration of one pixel in a TFT substrate of a conventional liquid crystal display panel. FIG. 2B is a schematic cross-sectional view of the liquid crystal display panel taken along the line BB ′ in FIG. FIG. 2C is a schematic cross-sectional view of the liquid crystal display panel taken along line CC ′ in FIG. FIG. 2D is a schematic cross-sectional view of the liquid crystal display panel taken along the line DD ′ in FIG.
In FIG. 2B to FIG. 2D, a polarizing plate and a retardation plate are omitted.

  The present invention is applied, for example, to a liquid crystal display panel in which a liquid crystal material 3 is sealed between a TFT substrate 1 and a counter substrate 2 as shown in FIGS. 1 (a) and 1 (b). At this time, the TFT substrate 1 and the counter substrate 2 are bonded by an annular sealing material 4 surrounding the display area DA, and the liquid crystal material 3 is surrounded by the TFT substrate 1, the counter substrate 2, and the sealing material 4. Sealed in space.

  When the liquid crystal display panel is a transmissive type or a transflective type, the lower polarizing plate 5A and the lower polarizing plate 5A and An upper polarizing plate 5B is provided. At this time, for example, one or more retardation plates may be provided between the TFT substrate 1 and the lower polarizing plate 5A and between the counter substrate 2 and the upper polarizing plate 5B, respectively. .

  Further, when the liquid crystal display panel is of a reflective type, the lower polarizing plate 5A, the retardation plate, etc. are usually unnecessary on the TFT substrate 1 side.

  Further, the display area DA of the liquid crystal display panel according to the present invention is set, for example, as a set of a plurality of pixels arranged in a matrix, and the configuration of one pixel is, for example, that shown in FIGS. The configuration is as shown in FIG.

  The TFT substrate 1 includes a plurality of scanning signal lines GL, a plurality of storage capacitor lines CL, a counter electrode CT, and a first insulating layer on the surface of a first insulating substrate SUB1 having a high light transmittance such as a glass substrate. A PAS1, a TFT element semiconductor layer SCT, a plurality of video signal lines DL, a TFT element drain electrode SD1 and a source electrode SD2, a second insulating layer PAS2, a pixel electrode PX, and an alignment film ORI1 are stacked.

  The counter electrode CT is formed of a conductive film having a high light transmittance such as an ITO film, for example. Further, the plurality of scanning signal lines GL and the plurality of storage capacitor lines CL are formed of a conductive film such as an aluminum film, for example. In addition, the plurality of storage capacitor lines CL are arranged between two adjacent scanning signal lines GL, and are electrically connected by a bus line or the like outside the display area DA.

  When forming the counter electrode CT, the plurality of scanning signal lines GL, and the plurality of storage capacitor lines CL, for example, first, an ITO film and an aluminum film are successively formed on the entire surface of the first insulating substrate SUB1. Then, after the aluminum film is etched to form a plurality of scanning signal lines GL and a plurality of storage capacitor lines CL, the ITO film is subsequently etched to form the counter electrode CT. When formed in such a procedure, for example, as shown in FIGS. 2B and 2D, between the first insulating substrate SUB1 and the scanning signal line GL and the first insulating substrate SUB1. The ITO film remains between the storage capacitor line CL.

  When forming the counter electrode CT, the plurality of scanning signal lines GL, and the plurality of storage capacitor lines CL, for example, an ITO film is formed on the entire surface of the first insulating substrate SUB1, and the ITO film is etched. After forming the counter electrode CT, an aluminum film is formed on the entire surface of the first insulating substrate SUB1, and the aluminum film is etched to form a plurality of scanning signal lines GL and a plurality of storage capacitor lines CL. It may be formed. Furthermore, after forming an aluminum film on the entire surface of the first insulating substrate SUB1 and etching the aluminum film to form a plurality of scanning signal lines GL and a plurality of storage capacitor lines CL, the first film The counter electrode CT may be formed by forming an ITO film on the entire surface of the insulating substrate SUB1 and etching the ITO film.

  The first insulating layer PAS1 is formed of, for example, a silicon oxide film. In addition to the function as the gate insulating film of the TFT element (active element), for example, contact between the scanning signal line GL and the video signal line DL is performed. , And functions as an insulating film that prevents contact between the storage capacitor line CL and the video signal line DL, and is formed on the entire surface of the first insulating substrate SUB1.

  The semiconductor layer SCT of the TFT element is formed of, for example, an amorphous semiconductor such as amorphous silicon or a polycrystalline semiconductor such as polycrystalline silicon. When forming the semiconductor layer SCT of the TFT element, for example, an amorphous silicon film is formed over the entire surface of the first insulating layer PAS1, and then the amorphous silicon film is etched. When the island-shaped semiconductor layer SCT is formed by etching the amorphous silicon film, for example, as shown in FIGS. 2A and 2B, the scanning signal line GL and the video signal line DL intersect. To prevent the contact between the scanning signal line GL and the video signal line DL and the contact between the storage capacitor line CL and the video signal line DL in a region where the storage capacitor line CL and the video signal line DL intersect. A short-circuit prevention layer SCS may be formed.

  The plurality of video signal lines DL, the drain electrode SD1 and the source electrode SD2 of the TFT element are formed on the surface of the first insulating layer PAS1 on which the semiconductor layer SCT of the TFT element and the like are formed.

  When forming the plurality of video signal lines DL, the drain electrode SD1 and the source electrode SD2 of the TFT element, for example, an aluminum film or the like is formed on the entire surface of the first insulating layer PAS1 in which the semiconductor layer SCT of the TFT element is formed. After the conductive film is formed, the aluminum film is formed by etching. At this time, the drain electrode SD1 of the TFT element is formed integrally with the video signal line DL, for example. In the TFT element shown in FIG. 2A, the planar shape of the drain electrode SD1 is U-shaped. However, the planar shape is not limited to this, and may be other planar shapes.

  The second insulating layer PAS2 is formed of, for example, a silicon oxide film or a silicon nitride film, and is formed over the entire surface of the first insulating substrate SUB1.

  The pixel electrode PX is formed of a conductive film having a high light transmittance such as an ITO film, for example, and is connected to the source electrode SD2 through the through hole TH.

  The pixel electrode PX and the counter electrode CT are electrodes for controlling the electric field that drives the liquid crystal molecules of the liquid crystal material 3, and the planar shape of the pixel electrode PX in the upper layer as viewed from the first insulating substrate SUB1 is, for example, As shown in FIG. 2C, it has a comb-like shape having a plurality of slits (openings) in a region overlapping with the counter electrode CT when seen in a plan view.

  The alignment film ORI1 is formed of, for example, a polyimide film, and is the uppermost layer on the surface of the first insulating substrate SUB1, in other words, the surface of the second insulating layer PAS2 (the surface on which the pixel electrode PX is formed). Arranged (formed) on top.

  On the other hand, the surface (surface facing the TFT substrate 1) of the insulating substrate SUB2 (hereinafter referred to as the second insulating substrate SUB2) of the counter substrate 2 is, for example, as shown in FIGS. 2 (b) to 2 (d). As shown, a light shielding film BM, color filters CFR, CFG, CFB, a planarizing film PAS3, a spacer PS, an alignment film ORI2, and the like are provided.

  The light shielding film BM is formed using a material having a light transmittance of almost 0, such as chromium, and the planar shape thereof is, for example, a mesh shape that divides the display area DA for each pixel. Yes.

  The color filters CFR, CFG, and CFB are filters provided when the liquid crystal display panel is compatible with color display. At this time, one pixel shown in FIG. 2A is called, for example, a sub-pixel, and one sub-pixel of an image or an image is constituted by three sub-pixels arranged in the extending direction of the scanning signal line GL. . At this time, the three sub-pixels constituting one dot of the video or image are, for example, a sub-pixel provided with a red color filter CFR, a sub-pixel provided with a green color filter CFG, and a blue color It consists of a sub-pixel provided with a filter CFB.

  The flattening film PAS3 is a film for flattening the surface of the second insulating substrate SUB2 on which the light shielding film BM and the color filters CFR, CFG, CFB are formed, for example.

The spacer PS is, for example, the distance between the two substrates at each point of the display area DA when the TFT substrate 1 and the counter substrate 2 are overlapped, in other words, the thickness of the liquid crystal material 3 in the area where the light of each pixel is transmitted. It is for making it uniform. In this case, the spacers PS, for example, partially exposing the photosensitive resist is developed frustoconical or cylindrical projection formed, top portion PS _T is generally flat surface viewed from the second insulating substrate SUB2 It has become. The spacer PS, for example, of the scanning signal line GL of the TFT substrate 1, the outer area of the region and TFT elements are arranged to intersect with the video signal lines DL, the flat surface of the top portion PS _T scan It is formed at a position facing the signal line GL.

  The alignment film ORI2 is formed of, for example, a polyimide film, and is disposed on the uppermost layer on the surface of the second insulating substrate SUB2, in other words, on the surface of the planarization film PAS3 (surface on which the spacer PS is formed). (It is formed.

  Further, at this time, the island-shaped first film 6 and the second film 7 are formed on the portion of the TFT substrate 1 facing the spacer PS, for example, as shown in FIGS. 2 (a) and 2 (d). Are arranged, and a projecting pedestal is provided on the surface on which the alignment film ORI1 is formed (the surface of the second insulating layer PAS2). For example, the first film 6 is a conductive film formed of the same material as the video signal line DL, and the second film 7 is a semiconductor film formed of the same material as the semiconductor layer SCT of the TFT element, for example. is there.

By the way, in the liquid crystal display panel configured as shown in FIGS. 2A to 2D, the alignment film ORI1 of the TFT substrate 1 and the alignment film ORI2 of the counter substrate 2 are respectively surfaces of the first insulating substrate SUB1. And formed on the uppermost layer of the surface of the second insulating substrate SUB2. Therefore, when overlapping the TFT substrate 1 and the opposing substrate 2, and the orientation film ORI2 the top portion PS _T of the spacer PS, orientation film ORI1 of the pedestal portion of the TFT substrate 1 is in contact. At this time, for example, when friction occurs at the contact portion between the alignment film ORI1 of the TFT substrate 1 and the alignment film ORI2 of the counter substrate 2 due to bending deformation of the liquid crystal display panel, the alignment films ORI1 and ORI2 at the contact portions due to the friction. May peel off and become a foreign material in the liquid crystal material 3. If the alignment films ORI1 and ORI2 are peeled off in the liquid crystal material 3, the alignment of the liquid crystal molecules in the periphery thereof is disturbed, resulting in a problem that display quality is deteriorated.

With respect to such problems, in the conventional liquid crystal display panel, for example, as shown in FIG. 2 (d), the thickness of the orientation film ORI2 on the top portion PS _T of the spacer PS of the counter substrate 2, substantially 0μm A method has been proposed (see, for example, Patent Document 3).

  However, even in the case of the configuration shown in FIG. 2D, regarding the alignment film ORI1 of the TFT substrate 1, the thickness of the alignment film ORI1 on the pedestal and the thickness of the alignment film ORI1 on the outside of the pedestal. However, they are almost the same thickness.

  Further, the height of the pedestal of the TFT substrate 1 is about the same as the sum of the thickness of the first film 6 and the thickness of the second film 7, and is sufficiently lower than the height of the spacer PS. Therefore, for example, it is very difficult to make the thickness of the alignment film ORI1 on the pedestal substantially 0 μm by a method called leveling as described in Patent Document 3 and the like.

  For this reason, the conventional liquid crystal display panel has a problem that the alignment film ORI1 is peeled off on the pedestal of the TFT substrate 1 and easily becomes a foreign substance in the liquid crystal material 3.

FIGS. 3A to 3E are schematic views for explaining a configuration example and a manufacturing method of the liquid crystal display panel of Example 1 according to the present invention.
FIG. 3A is a schematic plan view showing one configuration example of the TFT substrate in the liquid crystal display panel of Example 1. FIG. FIG. 3B is a schematic cross-sectional view showing a cross-sectional configuration immediately after the step of forming the first film and the second film in the manufacturing method of the TFT substrate of Example 1 is completed. FIG. 3C is a schematic cross-sectional view immediately after the step of forming the pixel electrode in the manufacturing method of the TFT substrate of Example 1 is completed. FIG. 3D is a schematic cross-sectional view illustrating a first-stage cross-sectional configuration in the step of forming the alignment film in the TFT substrate manufacturing method according to the first embodiment. FIG. 3E is a schematic cross-sectional view illustrating a second-stage cross-sectional configuration in the step of forming the alignment film in the TFT substrate manufacturing method according to the first embodiment.
FIGS. 3B to 3E show cross-sectional structures taken along line EE ′ of FIG.

  In the TFT substrate 1 in the liquid crystal display panel of Example 1, for example, the planar shape of the first film 6 disposed to provide the pedestal is formed as shown in FIG. That is, the first film 6 in the liquid crystal display panel of Example 1 has a circular shape with a part of the outer periphery when viewed in plan is set back in the center direction of the first film 6 and has a fan-shaped defect portion. It has become.

  At this time, the first film 6 and the second film 7 may be formed by the same procedure as the conventional method for manufacturing the TFT substrate 1. Therefore, when the first film 6 is formed of the same material as the video signal line DL and the second film 7 is formed of the same material as the semiconductor layer SCT of the TFT element, the first film 6 and the second film 7 are formed. Is disposed (formed) on the surface of the first insulating layer PAS1, for example, as shown in FIG.

  Next, when the second insulating layer PAS2 and the pixel electrode PX are formed on the first insulating layer PAS1, the cross-sectional configuration around the pedestal of the TFT substrate 1 is shown in FIG. 3C, for example. It becomes the composition like this. Since the second insulating layer PAS2 is an insulating film such as a silicon oxide film or a silicon nitride film formed by, for example, a CVD method, the entire film thickness is substantially uniform. For this reason, the portion of the surface of the second insulating layer PAS2 where the first film 6 and the second film 7 are formed protrudes from its periphery and becomes the pedestal. However, at the top of the pedestal, the portion where the first film 6 is missing is lower than the top of the first film 6.

  Next, the alignment film ORI1 is formed. When a polyimide alignment film is formed, for example, after the liquid alignment film material ORI1 'is printed or applied, the alignment film material ORI1' is baked or dried. When printing or applying the liquid alignment film material ORI1 ′, the thickness of the alignment film material ORI1 ′ immediately after that is almost uniform as shown in FIG. 3D, for example. Yes. However, when the surface of the second insulating layer PAS2 in the pedestal portion is uneven as in the liquid crystal display panel (TFT substrate 1) of Example 1, the alignment film material ORI1 ′ applied on the pedestal is For example, as shown in FIG. 3 (a), it flows from a defective portion of the first film 6 to a lower position. As a result, the thickness of the alignment film material ORI1 'at and around the pedestal portion is in a state as shown in FIG. 3 (e), for example. Therefore, if the alignment film material ORI1 'is baked or dried in the state shown in FIG. 3E, the thickness of the alignment film ORI1 on the pedestal can be substantially 0 μm.

  The method of printing or applying the liquid alignment film material ORI1 ′ may be any of the methods applied in the manufacturing process of the conventional TFT substrate 1, but the alignment film on the pedestal In order to facilitate the flow of the material ORI1 ′ to a low position, it is desirable to lower the viscosity of the alignment film material ORI1 ′. Therefore, it is desirable to apply the liquid alignment film material ORI1 'by, for example, an inkjet method.

  If a liquid crystal display panel is manufactured using the TFT substrate 1 thus obtained and the counter substrate 2 having the structure shown in FIGS. 2B to 2D, the alignment film ORI1 on the pedestal is formed. It is possible to prevent the display quality from being deteriorated due to peeling.

FIG. 4 is a schematic plan view illustrating a first modification of the liquid crystal display panel according to the first embodiment.
FIG. 5A is a schematic plan view illustrating a second modification of the liquid crystal display panel according to the first embodiment. FIG. 5B is a schematic plan view illustrating a third modification of the liquid crystal display panel according to the first embodiment. FIG. 5C is a schematic plan view illustrating a fourth modification of the liquid crystal display panel according to the first embodiment.

  In describing the configuration of the liquid crystal display panel of the first embodiment, in the plan view shown in FIG. 3A, only the first film 6 is formed into a circular plane pattern having a fan-shaped defect portion. However, the method for making the surface of the pedestal uneven is not limited to this. For example, as shown in FIG. 4, both the first film 6 and the second film 7 are formed in a circular shape having a fan-shaped defect portion. A planar pattern may be used. By doing so, the level difference formed on the surface of the pedestal becomes large, and the liquid alignment film material ORI1 'applied on the pedestal tends to flow to a low position.

  Further, the planar pattern of the first film 6 and the second film 7 may be a circular planar pattern having a rectangular defect as shown in FIG. 5A, for example.

  Further, the planar pattern of the first film 6 and the second film 7 may be a circular planar pattern having fan-shaped defects at two locations as shown in FIG. 5B, for example.

  Still further, the planar pattern of the first film 6 and the second film 7 may be a rectangular planar pattern in which a part of the outer periphery recedes in the center direction as shown in FIG. 5C, for example. Moreover, although illustration is abbreviate | omitted, it is needless to say that not only a quadrangle but the plane pattern of arbitrary polygons may be sufficient.

  5A to 5C show the case where the first film 6 and the second film 7 have similar shapes, the present invention is not limited to this, and the first film is not limited thereto. Of course, only 6 may be a plane pattern in which a part of the outer periphery recedes in the central direction.

  In Example 1, the first film 6 formed of the same material as the video signal line DL and the second film 7 formed of the same material as the semiconductor layer SCT of the TFT element are used to form the above-described TFT substrate 1. Although the case where the pedestal is provided has been described as an example, the present invention is not limited thereto, and the pedestal may be provided using only the first film 6 or only the second film 7. Furthermore, it goes without saying that the first film 6 and the second film 7 may be formed of a material different from that of the video signal line DL and the semiconductor layer of the TFT element.

FIGS. 6A and 6B are schematic views showing a configuration example of the liquid crystal display panel of Example 2 according to the present invention.
FIG. 6A is a schematic plan view showing one configuration example of the TFT substrate in the liquid crystal display panel of Example 2. FIG. FIG. 6B is a schematic cross-sectional view illustrating an example of a cross-sectional configuration taken along the line FF ′ in FIG.

  The TFT substrate 1 in the liquid crystal display panel of Example 2 includes, for example, a first film 6 and a first film 6 at the position where the pedestal is provided, as shown in FIGS. 6 (a) and 6 (b). A third film 8 is formed on the top. At this time, the first film 6 has a region that overlaps with and a region that does not overlap with the third film 8 when viewed in a plane, and the third film 8 has a first film 6 when viewed in a plane. And a non-overlapping region. That is, the first film 6 and the third film 8 include, for example, a region where only the first film 6 exists and only the third film 8 when the pedestal and its periphery are viewed in a plane. And a region where the first film 6 and the third film 8 overlap each other is formed.

  In the TFT substrate 1 of Example 2, the first film 6 is, for example, a conductive film formed in the same process as the video signal line DL, and the third film 8 is different from the video signal line DL. The conductive film formed in the step, the insulating film formed in a step different from the second insulating layer PAS2, or the semiconductor film formed in a step different from the semiconductor layer SCT of the TFT element.

  In the TFT substrate 1 of Example 2, the top of the pedestal, that is, the surface of the second insulating layer PAS2, has a portion where the first film 6 and the third film 8 overlap each other than the other portions. It is high. Therefore, when the liquid alignment film material ORI1 'is applied, the alignment film material ORI1' at the top of the pedestal flows to a lower position along the step at the top of the pedestal. As a result, the thickness of the alignment film material ORI1 'at and around the pedestal portion is in a state as shown in FIG. 6B, for example. Therefore, if the alignment film material ORI1 'is baked or dried in the state shown in FIG. 6B, the thickness of the alignment film ORI1 on the pedestal can be substantially 0 μm.

  If a liquid crystal display panel is manufactured using the TFT substrate 1 thus obtained and the counter substrate 2 having the structure shown in FIGS. 2B to 2D, the alignment film ORI1 on the pedestal is formed. It is possible to prevent the display quality from being deteriorated due to peeling.

FIG. 7 is a schematic plan view showing a first modification of the liquid crystal display panel of Example 2. FIG.
FIG. 8 is a schematic plan view illustrating a second modification of the liquid crystal display panel according to the second embodiment.

  In describing the configuration of the liquid crystal display panel of Example 2, in the configuration shown in FIGS. 6A and 6B, on the first film 6 formed in the same process as the video signal line DL, A third membrane 8 is on board. However, the method for making the surface of the pedestal uneven is not limited to this. For example, as shown in FIG. 7, a video signal line is formed on the second film 7 formed in the same process as the semiconductor layer of the TFT element. The structure which the 1st film | membrane 6 formed in the same process as DL rides on may be sufficient. With such a configuration, the step of forming the third film 8 becomes unnecessary, and the third film 8 can be formed by the same process as the conventional TFT substrate 1.

  In the configuration shown in FIG. 6A, the band-shaped third film 8 crosses the circular first film 6, but the present invention is not limited to this. For example, as shown in FIG. Alternatively, the circular first film 6 and the circular third film 8 may be partially overlapped.

  Although not shown in the drawings, the plane pattern of the first film 6 and the third film 8 may be an arbitrary polygon.

  Furthermore, although illustration is omitted, in the configuration as shown in FIG. 6A, the first film 6 has, for example, a fan-shaped defect portion as described in the first embodiment. Also good.

  The present invention has been specifically described above based on the above-described embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. is there.

  For example, in the first and second embodiments, the configuration of one pixel is a so-called horizontal electric field drive type liquid crystal display panel having a configuration as shown in FIGS. 2 (a) to 2 (d). The case where the invention is applied is taken as an example. However, the present invention is not limited to such a horizontal electric field drive type liquid crystal display panel, but a vertical electric field drive type liquid crystal display in which the pixel electrode PX is arranged on the TFT substrate 1 and the counter electrode CT is arranged on the counter substrate 2. It can also be applied to panels.

FIG. 9A to FIG. 9D are schematic views for explaining an application example of the present invention.
FIG. 9A is a schematic plan view showing a configuration example of a TFT substrate in a vertical electric field drive type liquid crystal display panel. FIG. 9B is a schematic cross-sectional view of the liquid crystal display panel taken along line GG ′ in FIG. FIG. 9C is a schematic cross-sectional view of the liquid crystal display panel taken along the line HH ′ of FIG. FIG. 9D is a schematic cross-sectional view of the liquid crystal display panel taken along line JJ ′ of FIG.
In FIGS. 9B to 9D, a polarizing plate and a retardation plate are omitted.

  Of the present invention, a vertical electric field drive type liquid crystal display panel to which the invention according to the first embodiment is applied has, for example, a configuration as shown in FIGS. 9 (a) to 9 (d).

  The TFT substrate 1 is formed on the surface of the first insulating substrate SUB1, for example, a plurality of scanning signal lines GL, a storage capacitor line CL, a first insulating layer PAS1, a semiconductor layer SCT of TFT elements, a video signal line DL, a TFT. A drain electrode SD1 and a source electrode SD2, a second insulating layer PAS2, a pixel electrode PX, and an alignment film ORI1 are arranged. Further, each component (scanning signal line GL, video signal line DL, etc.) in the TFT substrate 1 shown in FIGS. 9A to 9D is shown in FIGS. 2A to 2D. The detailed description is omitted because it has the same function as the above.

  The counter substrate 2 has the same basic configuration as that shown in FIGS. 2B to 2D, but between the planarizing film PAS3, the spacer PS, and the alignment film ORI2. A counter electrode CT is interposed.

  Also in such a vertical electric field drive type liquid crystal display panel, for example, the first film 6 is formed on the scanning signal line GL on the outside of the region intersecting with the video signal line DL and the region where the TFT element is disposed. By disposing the second film 7, the thickness of the alignment film ORI 1 at the top of the pedestal of the TFT substrate 1 can be substantially 0 μm.

  In Example 1 and Example 2, the first film 6 and the second film 7 or the first film 6 and the third film 8 are formed before forming the second insulating layer PAS2. Unevenness is formed on the top of the pedestal of the TFT substrate 1 (the surface of the second insulating layer PAS2). However, according to the present invention, a protruding pedestal is provided at a position of the surface of the TFT substrate 1 on which the alignment film ORI1 is formed, facing the spacer PS of the counter substrate 2, and the outer periphery of the pedestal is The height only needs to change once or more during one round of the outer periphery of the pedestal. Therefore, instead of forming the first film 6 and the second film 7, or the first film 6 and the third film 8, the pedestal of the TFT substrate 1 is, for example, the surface of the second insulating layer PAS2. In addition, a protruding pedestal may be formed of another insulating film or the like. At this time, if the height of the outer periphery of the pedestal changes once or more during one round of the outer periphery of the pedestal, the same effect as the liquid crystal display panels of the first and second embodiments can be obtained.

It is a schematic plan view which shows an example of schematic structure of the liquid crystal display panel concerning this invention. It is a schematic cross section of the liquid crystal display panel in the A-A 'line | wire of Fig.1 (a). It is a schematic top view which shows an example of a structure of one pixel in the TFT substrate of the conventional liquid crystal display panel. It is a schematic cross section of the liquid crystal display panel in the B-B 'line of Fig.2 (a). It is a schematic cross section of the liquid crystal display panel in the C-C 'line of Fig.2 (a). It is a schematic cross section of the liquid crystal display panel in the D-D 'line | wire of Fig.2 (a). 3 is a schematic plan view illustrating a configuration example of a TFT substrate in the liquid crystal display panel of Example 1. FIG. It is a schematic cross section which shows the cross-sectional structure immediately after the process of forming the 1st film | membrane and the 2nd film | membrane among the manufacturing methods of the TFT substrate of Example 1 was complete | finished. It is a schematic cross section immediately after the process of forming a pixel electrode in the manufacturing method of the TFT substrate of Example 1 is completed. It is a schematic cross section which shows the cross-sectional structure of the 1st step in the process of forming alignment film among the manufacturing methods of the TFT substrate of Example 1. FIG. It is a schematic cross section which shows the cross-sectional structure of the 2nd step in the process of forming the alignment film among the manufacturing methods of the TFT substrate of Example 1. 6 is a schematic plan view illustrating a first modification of the liquid crystal display panel of Embodiment 1. FIG. FIG. 10 is a schematic plan view showing a second modification of the liquid crystal display panel of Example 1. 6 is a schematic plan view illustrating a third modification of the liquid crystal display panel of Embodiment 1. FIG. 10 is a schematic plan view illustrating a fourth modification of the liquid crystal display panel of Embodiment 1. FIG. 6 is a schematic plan view illustrating a configuration example of a TFT substrate in a liquid crystal display panel of Example 2. FIG. It is a schematic cross section which shows an example of the cross-sectional structure in the F-F 'line | wire of Fig.6 (a). 10 is a schematic plan view illustrating a first modification of the liquid crystal display panel of Embodiment 2. FIG. 12 is a schematic plan view showing a second modification of the liquid crystal display panel of Example 2. FIG. It is a schematic top view which shows the example of 1 structure of the TFT substrate in the liquid crystal display panel of a vertical electric field drive system. It is a schematic cross section of the liquid crystal display panel in the G-G 'line | wire of Fig.9 (a). It is a schematic cross section of the liquid crystal display panel in the H-H 'line | wire of Fig.9 (a). It is a schematic cross section of the liquid crystal display panel in the J-J 'line | wire of Fig.9 (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... TFT substrate 2 ... Opposite substrate 3 ... Liquid crystal material 4 ... Sealing material 5A ... Lower polarizing plate 5B ... Upper polarizing plate SUB1 ... First insulating substrate GL ... Scanning signal line CL ... Retention capacitance line PAS1 ... First insulating layer SC ... TFT semiconductor layer DL ... Video signal line SD1 ... Drain electrode SD2 ... Source electrode PAS2 ... Second insulating layer PX ... Pixel electrode CT ... Counter electrode SUB2 ... Second insulating substrate BM ... Light shielding film CFR, CFG, CFB ... Color filter PAS3 ... Planarization film PS ... Spacer ORI1, ORI2 ... Alignment film ORI1 '... Alignment film material 6 ... First film 7 ... Second film 8 ... Third film

Claims (8)

A liquid crystal display panel in which a liquid crystal material is sealed between the first substrate and the second substrate;
The first substrate includes a first insulating substrate, a plurality of scanning signal lines, a plurality of video signal lines, a plurality of TFT elements, and a plurality of elements disposed on the surface of the first insulating substrate. and pixel electrodes, the scanning signal lines of the first insulating substrate, the video signal line, the TFT element, and a first alignment film the pixel electrodes are provided on the uppermost layer of the placed surface Have
The second substrate includes a second insulating substrate, a plurality of substantially columnar spacers disposed on the surface of the second insulating substrate, and a surface on which the spacers of the second insulating substrate are disposed. A second alignment film provided on the uppermost layer of the liquid crystal display device,
The surface of the first substrate on which the first alignment film is disposed has a projecting pedestal whose top is substantially flat at a position facing the spacer of the second substrate,
The height of the pedestal of the first substrate from the surface on which the first alignment film is disposed is higher than the height of the spacer from the surface of the second substrate on which the second alignment film is disposed. The distance between the outer periphery of the top and the surface of the first insulating substrate when viewed in a low plane is varied one or more times during one round of the outer periphery of the top of the pedestal. A liquid crystal display device characterized in that
It said pedestal, a liquid crystal display device characterized by island-shaped film sandwiched between an insulating layer is arranged.   The spacer of the second substrate is disposed at a position facing a region other than the region intersecting the video signal line and the region where the TFT element is disposed, of the scanning signal line of the first substrate. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is a liquid crystal display device.   3. The liquid crystal display device according to claim 1, wherein a part of an outer periphery of the island-shaped film recedes toward a center side of the island-shaped film when viewed in a plane.   The liquid crystal display device according to claim 3, wherein the island-shaped film is a conductive film made of the same material as the video signal line. An island-shaped first film and a second film sandwiched between the insulating layers are disposed in positions on the surface of the first insulating substrate facing the spacers of the second substrate. And
The first film has a region overlapping with the second film when viewed in a plane and a region not overlapping with the second film;
3. The liquid crystal display device according to claim 1, wherein the second film includes a region overlapping with the first film and a region not overlapping when viewed in a plan view.   6. The liquid crystal according to claim 5, wherein a region of the second film overlapping the first film runs on the first film as viewed from the first insulating substrate. Display device.   The first film is characterized in that a part of a portion of the outer periphery of the first film that does not overlap with the second film recedes toward the center of the first film when viewed in plan. Item 7. A liquid crystal display device according to item 6.   The first film is a semiconductor film made of the same material as the semiconductor layer of the TFT element, and the second film is a conductive film made of the same material as the video signal line. The liquid crystal display device according to claim 5.

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