JP2010049185A - Liquid crystal display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an IPS type liquid crystal display apparatus in which such a phenomenon is prevented that the inside of a counter substrate is electrified due to the gate voltage to be applied to a leader line of a scanning line and that a white void is generated on the periphery of a screen. <P>SOLUTION: The leader line 31 of the scanning line is covered with a shield electrode 107 formed by the same layer as that of a counter electrode 108. The leader line 31 of the scanning line is also formed under a sealing material 20. The shield electrode 107 is extended to the lower part of the sealing material 20 and covers all of leader lines 31 of the scanning line to be formed under the shield electrode 107, so that a shielding effect can be made higher. A loophole pattern 1071 is formed on the shield electrode 107 formed under the sealing material 20, thereby the deterioration in the adhesive strength between the shield electrode 107 and each of an inorganic passivation film 106 for sandwiching the shield electrode and an upper insulating film 109 can be prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device, and more particularly, to a liquid crystal display device that is a horizontal electric field method with excellent viewing angle characteristics and has no unevenness in the screen even around the display area.

  In a liquid crystal display device, there are a TFT substrate in which pixel electrodes and thin film transistors (TFTs) are formed in a matrix, and a counter substrate in which color filters are formed at locations corresponding to the pixel electrodes of the TFT substrate, facing the TFT substrate. The liquid crystal is sandwiched between the TFT substrate and the counter substrate. An image is formed by controlling the light transmittance of the liquid crystal molecules for each pixel.

  Since liquid crystal display devices are flat and lightweight, they are used in various fields. Small liquid crystal display devices are widely used in mobile phones and DSCs (Digital Still Cameras). In mobile phones, DSCs, and the like, there is a demand to increase the display screen while keeping the outer shape of the liquid crystal display device small. Then, a so-called frame around the display area is reduced. In the case of such a configuration, it is easy to be affected by potential fluctuations in the frame portion around the display area.

  On the other hand, viewing angle characteristics are a problem in liquid crystal display devices. The viewing angle characteristic is a phenomenon in which luminance changes or chromaticity changes when the screen is viewed from the front and when viewed from an oblique direction. The viewing angle characteristic is excellent in an IPS (In Plane Switching) system in which liquid crystal molecules are operated by a horizontal electric field.

  In “Patent Document 1”, in an IPS liquid crystal display device, a taper portion of a leader line of a scanning line is formed as an insulating film so that white spots are not generated around the display area due to noise from the leader line of the scanning line. The structure of covering with a conductive film via is described. That is, the pitch of the terminal portion connecting the scanning line and the external circuit is smaller than the pitch of the scanning line formed in the display region. The scanning line lead line connecting the terminal portion and the scanning line of the display region becomes an oblique wiring (taper) in order to adjust the pitch between the display region and the terminal portion. Since this oblique wiring portion has a wiring density larger than that of the display area and noise due to the scanning signal is likely to occur, in “Patent Document 1”, this portion is covered with a conductive film to reduce the influence of noise from the tapered portion. It is something to try. For the conductive film, the same ITO (Indium Tin Oxide) as the pixel electrode is used.

JP 2005-275054 A

  In the configuration described in “Patent Document 1”, the scanning line lead line is covered with the same ITO as the pixel electrode. When the scanning line lead line is covered with ITO, the adhesion between the ITO and the sealing material becomes a problem. Generally, an epoxy resin is used for the sealing material. The sealing material has good adhesiveness with an insulating film such as SiN and can maintain a good sealing property. However, the reliability of the seal when in direct contact with a conductive film such as ITO is unclear.

  When the scanning line lead line is covered with ITO formed simultaneously with the pixel electrode as in the configuration described in “Patent Document 1”, a problem arises in reliability depending on how the relationship with the sealing material is made. . Further, the extent to which the peripheral ITO is covered has an important influence on the shielding effect for the scanning line lead-out line, but "Patent Document 1" does not describe such a problem.

  Further, in the configuration of “Patent Document 1”, the ITO used for the shield of the scanning line lead line is the same ITO as the pixel electrode, and therefore cannot be formed continuously from the display region. At the boundary of the part, a part where the scanning line lead line is not covered with ITO occurs. Then, the influence of the scanning signal is generated from the portion not covered with the ITO.

  An object of the present invention is to remove white spots in a display area due to an influence of a scanning signal while maintaining reliability of sealing with a sealing material in an IPS liquid crystal display device.

  The present invention overcomes the above problems, and specific means are as follows.

  (1) A first electrode formed in a planar shape, a second electrode disposed on the first electrode via an insulating film, and pixels on which TFTs are formed are disposed in a matrix. A liquid crystal layer is sandwiched between a TFT substrate having a display area and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed around the TFT substrate and the counter substrate. A liquid crystal display device sealed with a sealing material, wherein scanning lines extend in a first direction and are arranged in a second direction in the display region of the TFT, and video signal lines are arranged in the second direction. A scanning line lead line for connecting a scanning line and a scanning line driving circuit is formed outside the display area, and the scanning line lead line is connected to the first direction. It is also formed under the seal material and covers the total number of the scanning line lead lines. A shield electrode formed in the same layer as the first electrode extends below the seal material, and the insulating film exists between the shield electrode and the seal material, The liquid crystal display device, wherein the same potential as that of the first electrode is applied to the shield electrode.

  (2) The liquid crystal display device according to (1), wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.

  (3) The total area of the plurality of extraction patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. The liquid crystal display device described.

  (4) A video signal line lead line for connecting the video signal line and the video signal drive circuit is formed outside the display area, and the shield electrode does not cover the video signal line lead line. (1) The liquid crystal display device according to (1).

  (5) The liquid crystal display device according to (1), wherein the first electrode and the shield electrode are a continuous film.

  (6) The first electrode formed in a planar shape, the second electrode disposed on the first electrode through an insulating film, and the pixels on which the TFTs are formed are disposed in a matrix. A liquid crystal layer is sandwiched between a TFT substrate having a display area and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed around the TFT substrate and the counter substrate. A liquid crystal display device sealed with a sealing material, wherein scanning lines extend in a first direction and are arranged in a second direction in the display region of the TFT, and video signal lines are arranged in the second direction. A scanning line lead line for connecting a scanning line and a scanning line driving circuit is formed outside the display area, and the scanning line lead line is connected to the first direction. It is also formed under the seal material and covers the total number of the scanning line lead lines. A shield electrode formed in the same layer as the first electrode extends below the seal material, and the insulating film exists between the shield electrode and the seal material, The liquid crystal display device, wherein the same potential as that of the second electrode is applied to the shield electrode.

  (7) The liquid crystal display device according to (6), wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.

  (8) The sum of the areas of the plurality of punched patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. The liquid crystal display device described.

  (9) The first electrode formed in a planar shape, the second electrode disposed on the first electrode via an insulating film, and the pixels on which the TFTs are formed are disposed in a matrix. A liquid crystal layer is sandwiched between a TFT substrate having a display area and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed around the TFT substrate and the counter substrate. A liquid crystal display device sealed with a sealing material, wherein scanning lines extend in a first direction and are arranged in a second direction in the display region of the TFT, and video signal lines are arranged in the second direction. The scanning line driving circuit is installed outside the sealing material in the second direction, and the scanning line and the scanning line are arranged outside the display area. A scanning line lead line for connecting the scanning line driving circuit is the second line. The scanning line lead lines are also formed under the seal material, and a shield electrode formed in the same layer as the first electrode covers the total number of the scanning line lead lines. The insulating film is present between the shield electrode and the seal material, and the same potential as that of the first electrode is applied to the shield electrode. A liquid crystal display device.

  (10) The liquid crystal display device according to (9), wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.

  (11) The sum of the areas of the plurality of extraction patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. The liquid crystal display device described.

(12) The first electrode formed in a planar shape, the second electrode disposed on the first electrode through an insulating film, and the pixels on which the TFTs are formed are disposed in a matrix. A liquid crystal layer is sandwiched between a TFT substrate having a display area and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed around the TFT substrate and the counter substrate. A liquid crystal display device sealed with a sealing material, wherein scanning lines extend in a first direction and are arranged in a second direction in the display region of the TFT, and video signal lines are arranged in the second direction. The scanning line driving circuit is installed outside the sealing material in the second direction, and the scanning line and the scanning line are arranged outside the display area. In order to connect the scanning line driving circuit, a scanning line lead line is connected to the first line. Extend in a direction of said scanning line lead lines also formed below the sealing material,
Covering the total number of the scanning line lead lines, a shield electrode formed in the same layer as the first electrode extends under the seal material, and between the shield electrode and the seal material The liquid crystal display device, wherein the insulating film is present, and the same potential as that of the second electrode is applied to the shield electrode.

  (13) The liquid crystal display device according to (12), wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.

  (14) The sum of the areas of the plurality of extraction patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. The liquid crystal display device described.

  According to the present invention, since all the scanning line lead lines for supplying the gate voltage to the scanning lines are covered with the shield electrode to which the common voltage is applied, the counter substrate can be prevented from being charged by the gate voltage. It is possible to prevent the whitening phenomenon that occurs around the display area due to the charging of.

  Further, in the present invention, since the shield electrode extends below the seal material, the influence of the gate voltage applied to the scanning line lead-out line can be more reliably prevented. Furthermore, in this invention, since an insulating film is installed between a shield electrode and a sealing material, the fall of the sealing effect of a sealing material part can be prevented.

  Furthermore, in the portion where the shield electrode overlaps with the seal material, the reliability of the seal portion can be improved by providing a punching pattern in the shield electrode and improving the adhesion between the shield electrode and the insulating film sandwiching it. .

  The contents of the present invention will be described in detail by the following examples.

  FIG. 1 is a plan view of a liquid crystal display device used in a mobile phone or the like using the present invention. In FIG. 1, a counter substrate 200 is installed on the TFT substrate 100. A liquid crystal layer is sandwiched between the TFT substrate 100 and the counter substrate 200. The TFT substrate 100 and the counter substrate 200 are bonded together by a sealing material 20 formed on the frame portion.

  A portion on the side opposite to the terminal portion 150 in FIG. 1 where a part of the sealing material is not formed becomes a liquid crystal sealing hole 21, and the liquid crystal is sealed from this portion. After the liquid crystal is sealed, the sealing hole 21 is sealed with a sealing material 22. The TFT substrate 100 is formed larger than the counter substrate 200, and a terminal for supplying power, a video signal, a scanning signal, etc. to the liquid crystal display device in a portion where the TFT substrate 100 is larger than the counter substrate 200. A portion 150 is formed.

  The terminal unit 150 is provided with an IC driver 50 for driving scanning lines, video signal lines, and the like. The IC driver 50 is divided into three regions, a video signal driving circuit 52 is installed at the center, and a scanning signal driving circuit 51 is installed on both sides.

  In the display area 10 of FIG. 1, scanning lines (not shown) extend in the horizontal direction and are arranged in the vertical direction. In addition, video signal lines (not shown) extend in the vertical direction and are arranged in the horizontal direction. The scanning line is connected to the scanning signal driving circuit 51 of the IC driver 50 by the scanning line lead line 31. In FIG. 1, in order to arrange the display area 10 in the center of the liquid crystal display device, the scanning line lead lines 31 are arranged on both sides of the display area 10, and for this reason, the IC driver 50 includes both scanning signal driving circuits 51. It is set aside. On the other hand, the video signal line lead line 41 connecting the video signal line and the IC driver 50 is collected on the lower side of the screen. The video signal line lead line 41 is connected to a video signal drive circuit 52 disposed at the center of the IC driver 50.

  Since the scanning signal supplies a gate voltage for turning on or off the TFT, the voltage is high. Therefore, the scanning signal is likely to cause noise inside the liquid crystal display device as compared with the video signal or the like. In particular, the periphery of the screen where the scanning line lead line 31 exists is easily affected by the scanning signal, as will be described later. As a result, white spots 11 are generated in a region shown by a dotted line in FIG. 1 around the screen. The portion of white spots 11 is in a state where the contrast has deteriorated.

  FIG. 2 is a cross-sectional view showing the configuration of the present invention in which such white spots are not generated. The liquid crystal display device shown in FIG. 2 is an IPS liquid crystal display device. FIG. 4 is a plan view of a TFT substrate of a similar liquid crystal display device. 2 is divided into a pixel portion A constituting a part of the display area 10 from the right side, a common wiring connecting portion B connecting the common wiring 60 and the shield electrode 107 or the counter electrode 108, and a scanning line lead line 31 portion C. Yes. As shown in FIG. 4, since the counter electrode 108 and the shield electrode 107 are formed as a continuous film, when the common voltage is supplied to the shield electrode 107, the common voltage is also supplied to the counter electrode 108 at the same time.

  First, the configuration of the pixel portion in FIG. 2 will be described. In FIG. 2, a gate electrode 101 is formed on a TFT substrate 100 made of glass. The gate electrode 101 is formed in the same layer as the scanning line 30. As for the gate electrode 101, Mo alloy is laminated | stacked on Al alloy.

  A gate insulating film 102 is formed of SiN so as to cover the gate electrode 101. A semiconductor layer 103 is formed of an a-Si film on the gate insulating film 102 at a position facing the gate electrode 101. The a-Si film is formed by plasma CVD. The a-Si film forms the channel portion of the TFT, and the drain electrode 104 and the source electrode 105 are formed on the a-Si film with the channel portion interposed therebetween. Note that an n + Si layer (not shown) is formed between the a-Si film and the drain electrode 104 or the source electrode 105. This is to make an ohmic contact between the semiconductor layer 103 and the drain electrode 104 or the source electrode 105.

  The drain electrode 104 is also used as the video signal line 40, and the source electrode 105 is connected to the pixel electrode 110. The drain electrode 104 and the source electrode 105 are simultaneously formed in the same layer. In this embodiment, the drain electrode 104 or the source electrode 105 is made of a Mo alloy. In order to lower the electrical resistance of the drain electrode 104 or the source electrode 105, for example, an electrode structure in which an Al alloy is sandwiched between Mo alloys is used.

  An inorganic passivation film 106 is formed of SiN so as to cover the TFT. The inorganic passivation film 106 protects the TFT, particularly the channel portion, from impurities. Although an organic passivation film may be formed on the inorganic passivation film 106, only the inorganic passivation film 106 is used in this embodiment.

  A counter electrode 108 is formed on the inorganic passivation film 106. The counter electrode 108 is formed by sputtering ITO (Indium Tin Oxide), which is a transparent conductive film, over the entire display region 10. That is, the counter electrode 108 is formed in a planar shape. After the counter electrode 108 is formed on the entire surface by sputtering, only the through hole portion for conducting the pixel electrode 110 and the source electrode 105 is removed by etching. At this time, a shield electrode 107 described later is formed at the same time.

  An upper insulating film 109 is formed of SiN so as to cover the counter electrode 108. After the upper insulating film 109 is formed, a through hole is formed by etching. Using the upper insulating film 109 as a resist, the inorganic passivation film 106 is etched to form the first through hole TH1. Thereafter, an ITO film that covers the upper insulating film 109 and the first through hole TH1 and becomes the pixel electrode 110 is formed by sputtering. The pixel electrode 110 is formed by patterning the sputtered ITO. The ITO that becomes the pixel electrode 110 is simultaneously deposited on the first through hole TH1, the second through hole TH2, and the third through hole TH3, and is patterned at the same time, and the second through hole TH2 and the second through hole TH3 are connected. The electrode 111 is formed. In the first through hole TH1, the source electrode 105 extending from the TFT and the pixel electrode 110 are brought into conduction, and the video signal is supplied to the pixel electrode 110.

  FIG. 3 shows an example of the pixel electrode 110. The pixel electrode 110 is a comb-like electrode with both ends closed. A slit 112 is formed between the comb teeth. A planar counter electrode 108 (not shown) is formed below the pixel electrode 110. When a video signal is applied to the pixel electrode 110, the liquid crystal molecules 301 are rotated by electric lines of force generated between the counter electrode 108 through the slit 112. As a result, light passing through the liquid crystal layer 300 is controlled to form an image.

  The pixel portion in FIG. 2 explains this state as a cross-sectional view. A slit 112 is formed between the comb-shaped electrode and the comb-shaped electrode. A common voltage is applied to the counter electrode 108, and a voltage based on a video signal is applied to the pixel electrode 110. When a voltage is applied to the pixel electrode 110, as shown in FIG. 2, electric lines of force are generated, and the liquid crystal molecules 301 are rotated in the direction of the electric lines of force to control the transmission of light from the backlight. Since transmission from the backlight is controlled for each pixel, an image is formed. Note that an alignment film 113 for aligning the liquid crystal molecules 301 is formed on the pixel electrode 110.

  In FIG. 2, the counter substrate 200 is installed with the liquid crystal layer 300 interposed therebetween. A color filter 201 is formed inside the counter substrate 200. The color filter 201 is formed with red, green, and blue color filters 201 for each pixel, and a color image is formed. A black matrix 202 is formed between the color filters 201 to improve the contrast of the image. However, since FIG. 2 is a cross-sectional view around the display area 10, only one color filter 201 is described, and most of the color filter 201 is covered with a black matrix 202 as a light shielding film.

  An overcoat film 203 is formed to cover the color filter 201 and the black matrix 202. Since the surface of the color filter 201 and the black matrix 202 is uneven, the surface is flattened by the overcoat film 203. An alignment film 113 for aligning the liquid crystal molecules 301 is formed on the overcoat film 203. 2 is IPS, the counter electrode 108 is formed on the TFT substrate 100 side, and is not formed on the counter substrate 200 side.

  As shown in FIG. 2, in IPS, a conductive film is not formed inside the counter substrate 200. Then, the potential of the counter substrate 200 becomes unstable. Further, external electromagnetic noise enters the liquid crystal layer 300 and affects the image. In order to eliminate such a problem, a surface conductive film 210 is formed outside the counter substrate 200. The surface conductive film 210 is formed by sputtering ITO, which is a transparent conductive film.

  In this manner, electromagnetic noise from the outside of the liquid crystal display device can be shielded by the surface conductive film 210, but the liquid crystal display device has an internal effect due to the influence of the gate voltage and the like generated inside the liquid crystal display device. Regarding the charging, the surface conductive film 210 cannot take measures. Such a problem is countered by the configuration of the present invention described below.

  A common voltage is applied to the counter electrode 108 from the common wiring 60. The common wiring 60 is formed in the same layer as the scanning line 30 or the gate electrode 101. The counter electrode 108 and the shield electrode 107 covering the scanning line lead line 31 in FIG. 2 are formed as a continuous film as shown in FIG. Therefore, as shown in FIG. 2, when the common wiring 60 and the shield electrode 107 are connected, the common wiring 60 and the counter electrode 108 are simultaneously connected.

  The connection between the common wiring 60 and the shield electrode 107 is as follows. Through holes are formed in the upper insulating film 109, the inorganic passivation film 106, and the gate insulating film 102 to expose a part of the common wiring 60. On the other hand, a through hole is formed in the upper insulating film 109 to expose a part of the shield electrode 107. When the ITO film for forming the pixel electrode 110 is sputtered, ITO is deposited at the same time, and this ITO film is patterned simultaneously with the pixel electrode 110 to form the connection electrode 111, and the shield electrode 107 and the counter electrode 108 is connected.

  In FIG. 2, a scanning line lead-out line part C is a part showing the characteristics of the present invention. The scanning line lead line 31 in FIG. 2 has a two-layer structure. In particular, in a small liquid crystal display device, there is a strong demand for narrowing the frame portion around the display area 10. The scanning line lead line 31 is disposed on the outer frame portion of the display area 10. When the scanning line lead lines 31 are arranged in the same layer, the scanning line lead lines 31 need to be spaced from each other, and there is a limit to reducing the frame portion.

  In the scanning line lead line 31 region of FIG. 2, the scanning line lead line 31 is divided into two layers of a first scanning line lead line 311 and a second scanning line lead line 312, thereby occupying the space occupied by the scanning line lead line 31. Is made smaller. In FIG. 2, the first scanning line lead line 311 is formed in the same layer as the scanning line 30 or the gate electrode 101, and the second scanning line lead line 312 is formed in the same layer as the video signal line 40 or the source electrode 105. Note that the scanning line 30 and the second scanning line lead line 312 are connected by a through hole not shown in FIG.

  Since the gate insulating film 102 exists between the first scan line lead line 311 and the second scan line lead line 312, the first scan line lead line 311 and the second scan line lead line are planar. 312 can be arranged without a gap, and can be arranged in an overlapping manner. Therefore, the frame area can be narrowed.

  The scanning line 30 and the scanning line lead-out line 31 are applied with a relatively high gate voltage that turns the TFT on and off. In particular, when the scanning line lead line 31 is not covered with the shield electrode 107 or the like, a part of the counter electrode 108 is charged by the influence of the gate voltage. In particular, when the black matrix 202 formed on the counter substrate 200 is formed of an insulating resin or the like, the black matrix 202 is easily charged. When the counter substrate 200 is charged, this influence is applied to the liquid crystal layer 300 and becomes noise with respect to the video signal, and white spots occur around the screen.

  According to the present invention, the influence of the gate voltage reaches the counter substrate 200 by extending the shield electrode 107 formed simultaneously with the counter electrode 108 to the bottom of the seal material 20 and covering all of the scanning line lead lines 31. It is preventing. The shield electrode 107 is formed of the same ITO film as the counter electrode 108. Further, an inorganic passivation film 106 made of SiN exists between the second scanning line lead line 312 and the shield electrode 107.

  The shield electrode 107 is covered with an upper insulating film 109. Therefore, the sealing material 20 and the ITO constituting the shield electrode 107 are not in direct contact. Therefore, the sealing material 20 comes into contact with the upper insulating film 109 that is an insulator, and the reliability of the sealing portion is high.

  However, since the shield electrode is formed over a wide range of the sealing material 20 in a plan view, there is a possibility that the reliability of the seal portion is lowered due to the presence of ITO which is not an insulator in this portion. Therefore, in this embodiment, the pattern 1071 is formed in the shield electrode that overlaps the seal material, and the adhesion between the shield electrode and the inorganic passivation film 106 and the upper insulating film 109 is improved in the seal portion. Yes.

  The planar shape of the extraction pattern 1071 can be a pan turn as shown in FIG. 5, for example. In FIG. 5, a square punching pattern 1071 is formed in a portion where the seal portion 20 and the shield electrode 107 overlap. In the portion where the extraction pattern is formed, the inorganic passivation film 106 and the upper insulating film 109 are in direct contact with each other, and the reliability of the entire seal portion is improved. Strictly speaking, in the portion where the extraction pattern 1071 is formed, the lower electrode lead line is not covered, but this is sufficient as an electric field shielding effect.

  The extraction pattern 1071 shown in FIG. 5 is not necessarily limited to a square as shown in FIG. FIG. 6 shows examples of various patterns that can be formed in the overlapping portion of the sealing material 20 and the shield electrode 1071. 6A is a vertical slit-shaped extraction pattern 1071, and FIG. 6B is a horizontal slit-shaped extraction pattern 1071. FIG. 6C shows a key-shaped pattern 1071, and FIG. 6D shows a zigzag pattern 1071. Such a pattern can be selected in accordance with the overlap shape of the shield electrode 107 and the sealing material 20.

  In FIG. 2, the common wiring 60 extends outside the shield electrode 107. Since the reference voltage is applied to the common wiring 60, there is no need for shielding. Therefore, no shield electrode exists above the common wiring 60. Note that the common wiring is formed in the same layer as the gate electrode, and is electrically connected to other common wiring in other portions not shown in FIG.

  FIG. 4 is a plan view of the TFT substrate 100 of the liquid crystal display device according to the present invention. In FIG. 4, the TFT substrate 100 is illustrated up to the sealing material 20. The sealing material 20 is indicated by a one-dot chain line. A terminal portion 150 (not shown) is formed on the lower side of FIG. In FIG. 4, scanning lines 30 extend in the horizontal direction and are arranged in the vertical direction in the display area 10. The video signal lines 40 extend in the vertical direction and are arranged in the horizontal direction. The scanning lines 30 are connected to scanning line lead lines 31 existing on both sides of the display area 10. In addition, the video signal line 40 is connected to a video signal line lead line 41 existing below the display area 10.

  The scanning line lead lines 31 existing on both sides of the display area 10 extend below the display area 10 and are connected to the scanning signal driving circuit 51 of the IC driver 50. The video signal line lead line 41 existing below the display area 10 is connected to a video signal driving circuit 52 existing further below the display area 10. In FIG. 4, the scanning line lead lines 31 are present without any gap in plan view. As described with reference to FIG. 2, the scanning line lead lines 31 have a two-layer structure and are insulated from each other by an insulating film, so that such an arrangement is possible.

  In FIG. 4, a common line 60 extends on the left side of the display region 10, and the common line 60 is connected to the shield electrode 107 through the second through hole TH2 and the third through hole TH3, and the shield electrode 107 and the continuous film. Is connected to the counter electrode 108 formed as follows. The entire display area 10 is covered with the counter electrode 108, and the scanning line lead lines 31 existing on both sides of the display area 10 are covered with the shield electrode 107. The counter electrode 108 and the shield electrode 107 are formed of a continuous film, and this state is indicated by hatching. Therefore, inside the sealing material 20, the scanning line 30 and the scanning line lead line 31 are all covered with the counter electrode 108 or the shield electrode 107 made of ITO. The shield electrode 107 covers the scanning line lead line 31, but does not cover the video signal line lead line 41. This is because the video signal has a low voltage and the possibility of charging the counter substrate 200 is small. In some cases, when the shield electrode 107 covers the video signal line lead line 41, the capacity between the video signal line lead lines 41 may increase, and the processing speed of the video signal may be adversely affected.

  The shield electrode 107 overlaps the sealing material 20 in a plan view. Further, the scanning line lead line 31 also overlaps with the sealing material 20 in order to narrow the frame. A portion of the shield electrode 107 that overlaps the sealing material 20 has a blanking pattern as shown in FIG. 5 and the like, but is omitted in FIG. 4 in order not to complicate the drawing.

  In FIG. 4, all the scanning line lead lines 31 overlapping the sealing material 20 are covered with the shield electrode 107. This can prevent the black matrix 202 and the like on the counter substrate from being charged due to the influence of the scanning voltage. Therefore, the white phenomenon around the screen does not occur.

  In FIG. 4, a scanning voltage is supplied to the scanning line 30 by the left scanning line lead-out line 31 in the area on the opposite side of the terminal area 15 of the display area 10, and the area on the terminal area 150 side of the display area 10 is on the right side. A scanning voltage is supplied to the scanning line 30 by the scanning line lead line 31.

  In FIG. 4, the common wiring 60 is formed between the video signal line 41 and the scanning line 31, but the common wiring 60 also extends outside the scanning line 31. This is to reduce the resistance of the common wiring 60 and prevent a voltage drop in the common wiring.

  The common wiring 60 formed outside the scanning line lead line 31 extends to the opposite side of the terminal portion 150 and is formed so as to surround the display area 10. Further, on the side opposite to the terminal portion 150 in FIG. 4, the shield electrode 107 is also formed so as to cover the common wiring 60.

  Further, the shield electrode 107 and the common electrode 60 are also formed so as to overlap the sealing material 20 on the side opposite to the terminal portion 150. However, the sealing material 20 has an open portion in a part of the side opposite to the terminal portion, and this portion becomes the liquid crystal sealing hole 21. Note that the shield electrode 107 and the common wiring 60 are continuously formed even in the portion where the sealing hole 21 is formed.

  As described above, according to the present embodiment, the scanning line lead lines 31 are all covered with the shield electrode 107 inside the sealing material 20 and in a portion overlapping with the sealing material 20, so that they are opposed by the gate voltage. The problem that the black matrix 202 or the like formed inside the substrate 200 is charged can be avoided. Further, since the shield electrode 107 is formed continuously with the counter electrode 108 formed in a plane, the shield electrode 107 and the counter electrode 108 formed in the display region 10 can be connected without a break. Accordingly, since the scanning line lead line 31 is substantially completely covered by the shield electrode, an excellent shielding effect can be obtained.

  Furthermore, according to the present embodiment, the shield electrode 107 made of ITO and the sealing material 20 are not in direct contact with each other, and the sealing material 20 is in contact with only the insulating film, so that the reliability of the seal portion can be lowered. No. In addition, since the extraction pattern 1071 is formed in the shield electrode 107 in the portion overlapping with the sealing material 20, it is possible to avoid the problem of the adhesive force between the shield electrode 107 and the upper insulating film 109 or the inorganic passivation film 106. I can do it.

  FIG. 7 is a comparative example for the present invention. 7 is a cross-sectional view of the periphery of the liquid crystal display device shown in FIG. 1, similar to FIG. The configuration in FIG. 7 is the same as the configuration in FIG. 2 except for the shield electrode 107. In FIG. 7, the shield electrode 107 does not overlap with the sealing material 20, and the scanning line lead line 31 extends between the inorganic passivation film 106 and the upper insulating film 109 between the inside of the sealing material 20 and the end of the shield electrode. There is a region d facing the counter substrate 200 via Therefore, the inside of the counter substrate 200 is charged by the influence of the gate potential in the region d. Then, the effect of charging inside the counter substrate 200 affects the liquid crystal layer 300, and white spots as shown in FIG. 1 occur around the screen.

  FIG. 8 is a plan view of the TFT substrate 100 in the comparative example. FIG. 8 is the same as FIG. 4 except for the range of the shield electrode 107. In FIG. 8, a sealing material 20 is formed around the TFT substrate 100. The sealing material is indicated by a one-dot chain line. Scan line lead lines 31 are provided on both sides of the display area 10. The shield electrode 107 does not cover the entire inside of the sealing material 20 and the end of the display area 10 but covers only a part thereof. That is, a region d where the scanning line lead line 31 is not covered exists inside the sealant 20. Then, the inside of the counter substrate 200 is charged by the gate voltage applied to the scanning line lead line 31 in this region d. Then, as described in the description of FIG. 7, white spots occur around the display area 10.

  As described above, even if the shield electrode 107 is provided on the scanning line lead line 31 in the same layer as the counter electrode 108, the shield electrode 107 extends to the range where it overlaps with the sealing material 20, and the scanning line lead line is formed. If substantially 31 is not covered, a sufficient effect against white spots cannot be obtained.

  In the IPS liquid crystal display device according to the first embodiment, the planar counter electrode 108 is formed on the inorganic passivation film 106, the upper insulating film 109 is formed thereon, and the comb-like pixel electrode 110 is formed thereon. Forming. Contrary to the electrode arrangement of the liquid crystal display device of Embodiment 1, a planar pixel electrode 110 may be formed on the inorganic passivation film 106 and a comb-like counter electrode 108 may be formed with the upper insulating film 109 interposed therebetween. Good. FIG. 9 shows this example. In this case, the shape of the counter electrode 108 may be the same as that of the comb electrode of FIG.

  In FIG. 9, a planar pixel electrode 110 is formed on the inorganic passivation film 106 in the pixel portion. An upper insulating film 109 is formed on the planar pixel electrode 110, and a comb-like counter electrode 108 is formed on the upper insulating film 109. The shield electrode 107 covering the scanning line lead line 31 is formed of an ITO film simultaneously with the formation of the pixel electrode 110. The shield electrode 107 is formed at the same time as the pixel electrode 110. The shield electrode 107 is supplied with a common potential from the common wiring 60 through the second through hole TH2 and the third through hole TH3. Therefore, in Example 2, the ITO film constituting the pixel electrode 110 and the ITO film constituting the shield electrode 107 are not continuous films.

  The configuration shown in FIG. 9 can be formed by the following process. The formation up to the inorganic passivation film 106 is the same as in Example 1 shown in FIG. After the inorganic passivation film 106 is formed, a first through hole TH1 for connecting the pixel electrode 110 and the source electrode 105 of the TFT is formed. Thereafter, ITO is sputtered. By patterning the deposited ITO film, the pixel electrode 110, the through-hole contact and the shield electrode 107 are formed. In this case, the pixel electrode 110 and the shield electrode 107 are not continuous films.

  Thereafter, the upper insulating film 109 is formed of SiN. Next, as in the first embodiment, the second through hole TH2 and the third through hole TH3 are formed. Thereafter, ITO to be the counter electrode 108 is deposited by sputtering. By patterning this ITO, comb-shaped counter electrodes 108 and through-hole contacts are formed. Of the through holes, only the first through hole TH1 that connects the source electrode 105 of the TFT and the pixel electrode 110 is different from that of FIG.

  As in the first embodiment, the shield electrode 107 is formed up to the bottom of the sealing material 20 in plan view. The common voltage is applied to the shield electrode 107 as in the first embodiment. Accordingly, the IPS liquid crystal display device of the type in which the planar pixel electrode 110 is disposed on the lower side and the counter electrode 108 is formed in a comb shape via the insulating film is the same as in the first embodiment. The effect of can be obtained.

  In the portion where the shield electrode 107 overlaps with the seal material 20, a blanking pattern 1071 is formed on the shield electrode 107, whereby the upper insulating film 109 sandwiching the shield electrode 107, the inorganic passivation film 106, and the shield electrode It is the same as that of Example 1 that the adhesive strength with 107 is improved.

  A common wiring 60 is formed outside the scanning line lead line 31. The common wiring 60 extends in the direction of the side opposite to the side where the terminal portion 150 is formed, and is formed so as to surround the display region 10. Further, the common wiring 60 is covered with the shield electrode 107 as in the case described with reference to FIG.

  In Example 1 and Example 2, in the part where the shield electrode 107 overlaps with the sealing material 20, a punching pattern is used to improve the adhesion between the shield electrode 107, the upper insulating film 109, and the inorganic passivation film 106. 1071 is formed.

  The area of the extraction pattern 1071 is preferably small from the viewpoint of eliminating the influence of the scanning voltage from the scanning line lead line 31. On the other hand, in order to improve the adhesive force between the shield electrode 107, the upper insulating film 109, and the inorganic passivation film 106, a larger area is better.

  In this embodiment, in order to solve such a dilemma, in the portion where the shield electrode 107 overlaps with the seal portion 20, the area of the extraction pattern 1071 is decreased on the display region 10 side and increased on the outer side. Yes. An example of the blank pattern 1071 in this embodiment is shown in FIG.

  In FIG. 10, the alternate long and short dash line is the seal material 20, and the shaded portion is the shield electrode 107. A punching pattern 1071 is formed in a portion where the sealing material 20 and the shield electrode 107 overlap. The blank pattern 1071 has a triangular shape and has a small area on the right display area side. That is, in the portion closer to the display area, the area of the blank pattern 1071 is reduced, and the shielding effect is further improved. On the other hand, in the portion overlapping the common wiring 60 formed outside the scanning line lead-out line 31, the area of the extraction pattern is large, so that the reliability of adhesion between the shield electrode 107, the upper insulating film 109, and the inorganic passivation film 106 is increased. The property is excellent. As described above, according to the present embodiment, it is possible to simultaneously solve the problem of the shielding effect by the shield electrode 107 and the improvement of the adhesion between the shield electrode 107 and the insulating films formed above and below it.

  In FIG. 10, the blank pattern 1071 is described as being a triangle, but it is not necessary to limit to a triangle as long as the same effect can be obtained. FIG. 11 shows another example. In FIG. 11, a trapezoidal punching pattern 1071 is formed, and the size of the trapezoid is increased toward the outside, thereby simultaneously solving the problems of the shielding effect and the adhesive force described in FIG.

  In other words, the example of FIG. 10 and FIG. 11 has a plurality of extraction patterns 1071 of the shield electrode 107 formed under the sealing material 20, and the inner side and the outer side in the width direction of the sealing material 20. In other words, the total area of the plurality of punch patterns is larger on the outer side in the width direction of the sealing material 20 than on the inner side.

  FIGS. 10 and 11 show examples of the punch pattern 1071 in this embodiment. Even if the punch pattern has another shape, the total area of the punch pattern 1071 is increased outside the inner side in the width direction of the sealing material. By doing so, the effect of the present embodiment can be realized.

It is a top view of the liquid crystal display device with which this invention is applied. 1 is a cross-sectional view of a liquid crystal display device according to the present invention. FIG. 3 is a plan view of the pixel electrode of FIG. 2. It is a top view of the TFT substrate of the liquid crystal display device by this invention. It is an example of the extraction pattern of a shield electrode. It is another example of the extraction pattern of a shield electrode. It is sectional drawing of the liquid crystal display device of a comparative example. It is a top view of the TFT substrate of the liquid crystal display device of a comparative example. 6 is a cross-sectional view of a liquid crystal display device of Example 2. FIG. It is an example of the shield electrode extraction pattern of Example 3. It is another example of the shield electrode extraction pattern of Example 3.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Display area, 11 ... Blank, 20 ... Sealing material, 21 ... Sealing hole, 22 ... Sealing material, 30 ... Scan line, 31 ... Scan line lead line, 40 ... Video signal line, 41 ... Video signal line lead 50 ... IC driver 51 ... Scanning signal drive circuit 52 ... Video signal drive circuit 60 ... Common wiring 100 ... TFT substrate 101 ... Gate electrode 102 ... Gate electrical insulating film 103 ... Semiconductor layer 104 ... Source electrode 105 ... Drain electrode 106 ... Inorganic passivation film 107 ... Shield electrode 108 ... Counter electrode 109 ... Upper insulating film 110 ... Pixel electrode 111 ... Connecting electrode 112 ... Slit 113 ... Alignment film 150 ... Terminal part 200 ... Counter substrate 201 ... Color filter 202 ... Black matrix 203 ... Over Coat film, 210 ... surface conductive film, 300 ... liquid crystal layer, 301 ... liquid crystal molecule, 311 ... first scanning line lead line, 312 ... second scanning line lead line, 1071 ... shield electrode extraction pattern, TH1 ... first through hole TH2 ... second through hole, TH3 ... third through hole.

Claims (14)

A display region in which a first electrode formed in a planar shape, a second electrode disposed on the first electrode via an insulating film, and pixels in which TFTs are formed are disposed in a matrix A liquid crystal layer is sandwiched between a TFT substrate having the TFT substrate and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed by a sealing material formed around the TFT substrate and the counter substrate. A sealed liquid crystal display device,
In the display area of the TFT, scanning lines extend in the first direction and are arranged in the second direction, and video signal lines extend in the second direction and are arranged in the first direction. And
A scanning line lead line connecting the scanning line and the scanning line driving circuit is formed outside the display area,
The scanning line lead line is also formed under the sealing material,
Covering the total number of the scanning line lead lines, a shield electrode formed in the same layer as the first electrode extends under the seal material, and between the shield electrode and the seal material The insulating film is present;
The liquid crystal display device, wherein the same potential as that of the first electrode is applied to the shield electrode.   The liquid crystal display device according to claim 1, wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.   2. The total area of the plurality of punching patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. Liquid crystal display device.   A video signal line lead line connecting the video signal line and the video signal drive circuit is formed outside the display area, and the shield electrode does not cover the video signal line lead line. The liquid crystal display device according to claim 1.   The liquid crystal display device according to claim 1, wherein the first electrode and the shield electrode are a continuous film. A display region in which a first electrode formed in a planar shape, a second electrode disposed on the first electrode via an insulating film, and pixels in which TFTs are formed are disposed in a matrix A liquid crystal layer is sandwiched between a TFT substrate having the TFT substrate and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed by a sealing material formed around the TFT substrate and the counter substrate. A sealed liquid crystal display device,
In the display area of the TFT, scanning lines extend in the first direction and are arranged in the second direction, and video signal lines extend in the second direction and are arranged in the first direction. And
A scanning line lead line connecting the scanning line and the scanning line driving circuit is formed outside the display area,
The scanning line lead line is also formed under the sealing material,
Covering the total number of the scanning line lead lines, a shield electrode formed in the same layer as the first electrode extends under the seal material, and between the shield electrode and the seal material The insulating film is present;
The liquid crystal display device, wherein the same potential as that of the second electrode is applied to the shield electrode.   The liquid crystal display device according to claim 6, wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.   7. The liquid crystal according to claim 6, wherein a total area of the plurality of punching patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. Display device. A display region in which a first electrode formed in a planar shape, a second electrode disposed on the first electrode via an insulating film, and pixels in which TFTs are formed are disposed in a matrix A liquid crystal layer is sandwiched between a TFT substrate having the TFT substrate and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed by a sealing material formed around the TFT substrate and the counter substrate. A sealed liquid crystal display device,
In the display area of the TFT, scanning lines extend in the first direction and are arranged in the second direction, and video signal lines extend in the second direction and are arranged in the first direction. And
A scanning line driving circuit is installed outside the sealing material in the second direction, and a scanning line lead-out line for connecting the scanning line and the scanning line driving circuit is outside the display area. Extending in the direction of
The scanning line lead line is also formed under the sealing material,
Covering the total number of the scanning line lead lines, a shield electrode formed in the same layer as the first electrode extends under the seal material, and between the shield electrode and the seal material The insulating film is present;
The liquid crystal display device, wherein the same potential as that of the first electrode is applied to the shield electrode.   The liquid crystal display device according to claim 9, wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.   10. The liquid crystal according to claim 9, wherein a total area of the plurality of punching patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. Display device. A display region in which a first electrode formed in a planar shape, a second electrode disposed on the first electrode via an insulating film, and pixels in which TFTs are formed are disposed in a matrix A liquid crystal layer is sandwiched between a TFT substrate having the TFT substrate and a counter substrate facing the TFT substrate and having a color filter formed thereon, and the liquid crystal layer is formed by a sealing material formed around the TFT substrate and the counter substrate. A sealed liquid crystal display device,
In the display area of the TFT, scanning lines extend in the first direction and are arranged in the second direction, and video signal lines extend in the second direction and are arranged in the first direction. And
A scanning line driving circuit is installed outside the sealing material in the second direction, and a scanning line lead line is connected to the scanning area driving circuit to connect the scanning line and the scanning line driving circuit outside the display area. Extending in the direction of 2,
The scanning line lead line is also formed under the sealing material,
Covering the total number of the scanning line lead lines, a shield electrode formed in the same layer as the first electrode extends under the seal material, and between the shield electrode and the seal material The insulating film is present;
The liquid crystal display device, wherein the same potential as that of the second electrode is applied to the shield electrode.   The liquid crystal display device according to claim 12, wherein a plurality of punching patterns are formed on the shield electrode formed under the sealing material.   13. The liquid crystal according to claim 12, wherein a total area of the plurality of punching patterns of the shield electrode formed under the sealing material is larger on the outer side than on the inner side in the range of the width of the sealing material. Display device.

Images