JP4048228B2 - Display device substrate, method for correcting the same, method for correcting the display device, and liquid crystal display device - Google Patents

Description

The present invention relates to a display device substrate, a correction method thereof, a correction method of a display device, and a liquid crystal display device. More specifically, the present invention relates to a display device substrate suitably used for a direct-view type liquid crystal display such as a liquid crystal color television or a projection type liquid crystal display such as a liquid crystal projector, a correction method thereof, a display device correction method, and a liquid crystal display device.

As an example of a liquid crystal display device, an active matrix (hereinafter referred to as “AM”) substrate on which a plurality of switching elements such as thin film transistors (hereinafter referred to as “TFT”) are formed, and a color filter (hereinafter referred to as “CF”). A color liquid crystal display device having a CF substrate on which a layer and a common electrode are sequentially laminated, and a liquid crystal layer interposed between the two substrates. A plurality of pixel electrodes arranged in a matrix are formed on the AM substrate, and a common electrode facing the pixel electrode is formed on the CF substrate, and the alignment of the liquid crystal is controlled by the electric field strength between the two electrodes. is doing.

In the conventional liquid crystal display device, when a conductive foreign matter enters between the pixel electrode formed on the AM substrate and the common electrode formed on the CF substrate and is electrically short-circuited (hereinafter referred to as “upper and lower leakage”), Since there is no potential difference between the pixel electrode and the common electrode, and the liquid crystal molecules in the corresponding part are not aligned, the normally white (white display when no voltage is applied) method is used to make a bright spot and normally black (when no voltage is applied). In the case of the black display method, the pixel defect is that black spots are formed. This vertical leak is caused by the adhesion of conductive foreign matter in the TFT process, CF process, and liquid crystal process. In order to detect the vertical leak, it is necessary to perform a lighting inspection with the TFT and CF panels bonded together. is there. In addition, the probability of occurrence of such top and bottom leaks increases due to the increase in the size of pixels associated with the recent increase in the size of display devices and the narrowing of the cell gap to achieve high-speed response. Yield is decreasing.

A pixel structure of a conventional liquid crystal display device will be described with reference to the drawings by taking, for example, a pixel structure in an MVA (Multi-domain Vertical Alignment) liquid crystal display mode as an example.
In the MVA method, a band-shaped structure (alignment control protrusion) provided on the CF substrate and pixel electrode removal (slit) provided on the AM substrate side are alternately arranged on the substrate surface, and the structure This is a method in which the orientation of the liquid crystal molecule director (director) is 180 ° different from that of the object or slit to form a vertical alignment type liquid crystal, and the vertical direction liquid crystal orientation is divided. This is a system in which the viewing angle characteristics are made uniform by forming a plurality in the pixel region (see, for example, Patent Document 1). As described above, the MVA pixel electrode has a slit for regulating the alignment of liquid crystal molecules. In order to obtain a continuous electrode pattern in the pixel, for example, as shown in FIG. An inter-connection portion (pixel electrode connection portion) 12 is provided. In general, the pixel electrode connection portion 12 is provided around the pixel electrode 9 and is provided on the CF substrate side in combination with alignment failure (disclination) and leakage light near the data signal wiring (signal line) 4. In addition, light shielding is performed with a light-shielding film called a black matrix, thereby suppressing a decrease in aperture ratio. However, the conventional MVA pixel electrode structure has room for improvement in that the pixel in which the vertical leak has occurred cannot be corrected, resulting in a pixel-by-pixel defect.

A structure in which alignment control protrusions are provided on the AM substrate and slits are provided in the electrodes on the CF substrate is also one embodiment of the MVA method. In this case, for example, as shown in FIG. Since the counter electrode (common electrode) on the CF substrate side has a slit, and the counter electrode is continuous with the adjacent pixel, the pixel electrode at the corresponding location is used to separate the location where the vertical leak occurs. It is necessary to separate the surroundings. Therefore, there is room for devising to make it possible to minimize the number of cut portions and to make it difficult to be recognized as a defect by making the vertical leak occurrence portion a minute defect.

With respect to conventional techniques for correcting pixel defects, liquid crystal display devices and the like that can cope with the occurrence of vertical leaks by forming slit portions in pixel electrodes are disclosed (for example, see Patent Documents 2 to 4). However, the liquid crystal display devices and the like disclosed in Patent Documents 2 and 3 are provided with slits outside the light-shielding film and where no slits originally exist, and are intended to enlarge the slit region by cutting the pixel electrode. Therefore, there is room for contrivance to maintain display quality without causing orientation failure. Further, there is a possibility that the data signal wiring may be cut when the defective portion is removed, and there is room for improvement in that a line defect may be caused.
In addition, in the liquid crystal display devices of Patent Documents 2 and 4, when a defect occurs in the vicinity of the auxiliary capacitor, if the pixel electrode in the corresponding part is removed, the pixel electrode forming the auxiliary capacitor is cut off. However, there was room for improvement to make the auxiliary capacity function sufficiently and maintain the display quality.
Furthermore, the liquid crystal display devices of Patent Documents 2 to 4 adopt a structure in which a drain potential is supplied from a contact hole to a pixel electrode in the vicinity of a transistor, and when a vertical leak occurs between the transistor and an auxiliary capacitance line. There is room for improvement in order to make it possible to partially correct the pixel electrode. In addition to the upper and lower leaks, the drain extraction electrode and the auxiliary capacitance line (Cs) are electrically short-circuited (hereinafter referred to as “D-Cs leak”), the capacitance electrode formed on the auxiliary capacitance line and the data signal There is room for improvement in order to more fully cope with a failure mode such as an electrical short circuit between wirings.
Japanese Patent Laid-Open No. 11-242225 JP 2000-221527 A JP 2004-93654 A JP 2001-83522 A

The present invention has been made in view of the above-mentioned present situation, and by making the upper and lower leak occurrence locations due to the adhesion of conductive foreign substances into minute defects, it is difficult to recognize them as defects and maintains high display quality, yield. In addition, the substrate for a display device can cope with a failure mode such as a D-Cs leak or an electrical short circuit between the capacitor electrode formed on the auxiliary capacitor wiring and the signal line. An object of the present invention is to provide a correction method, a correction method of a display device including the display device substrate, and a liquid crystal display device.

The inventors of the present invention have studied various types of display device substrates capable of correcting pixel defects caused by vertical leaks, and provided electrode slits in the electrodes and corrected them using the electrical connection portions of the electrode slits. Thus, attention is paid to the fact that pixel defects can be corrected even when vertical leaks occur. In other words, when an active matrix substrate is taken as an example, vertical leakage occurs due to the structure in which the pixel electrode slit is electrically connected (interelectrode slit connection portion) so that the pixel electrode can be divided into one pixel or less. It was noted that the vertical leak correction can be performed by separating the pixel electrode at the connection portion. Here, since the vertical leak is caused by various processes such as TFT process, CF process, liquid crystal process, etc., it cannot be found unless the TFT substrate and the CF substrate are bonded together and inspected for lighting. In order to cut the pixel electrode connecting portion), it is necessary to carry out from the back surface of the substrate. As a correction method, correction is performed by laser irradiation. As shown in FIG. 1B, the pixel electrode 9 at the location where the vertical leak occurs is cut at the slit connecting portion 12 in the conventional liquid crystal display device. When trying to correct, the connection portion 12 is cut from the back surface of the AM substrate by laser irradiation (hereinafter referred to as “laser cut”), so the metal wiring (metal wiring) is cut simultaneously with the connection portion 12. There is a possibility that. In view of this state, the present inventors have found that the interelectrode slit connecting portion 12 is disposed outside the light shielding region where the metal wiring or the like is disposed, as shown in FIG. It has been found that even if the pixel electrode 9 is separated from the back surface of the AM substrate by laser irradiation, the signal line and the scanning line are not cut, so that the defective portion can be separated and made into a minute defect without affecting the adjacent pixels. In addition, there was a concern about the alignment failure of the liquid crystal molecules around the connection part by moving the connection part between the electrode slits outside the light shielding area, but there was no significant influence on the display quality as a whole pixel. When the connection part 12 is cut off, it approaches the original desired shape of the pixel electrode slit of the MVA method, etc., and thus it is found that the influence on the display quality of the pixel electrode that is operating normally after correction is extremely small. I came up with a solution.
In addition, by forming a light-shielding region from the light-shielding structure and the discontinuous light-shielding structure of the adjacent pixel, or by marking the installation position of the electrode slit connection portion according to the shape of the light-shielding structure, Even when the connecting portion is arranged in the case, the position of the connecting portion can be easily confirmed visually so that it can be corrected and the same action and effect can be exhibited. It is.
In addition to the vertical leak, the display device substrate of the present invention has a failure mode such as a D-Cs leak or an electrical short circuit between the capacitor electrode formed on the auxiliary capacitance wiring and the signal line. Even if it corresponds, it can fully respond.

That is, the present invention includes an active matrix substrate and a counter substrate facing each other with a display medium layer interposed therebetween, the active matrix substrate having pixel electrodes arranged in a matrix on the display medium layer side, and the counter substrate is A display device substrate having a structure having a common electrode facing a pixel electrode on a display medium layer side, wherein the display device substrate has an electrode slit formed in the pixel electrode or the common electrode, and the electrode slit The electrical connection part is a display device substrate in which at least one of the electrical connection parts is provided outside the light shielding region.

The present invention also includes an active matrix substrate and a counter substrate facing each other across the display medium layer, the active matrix substrate having pixel electrodes arranged in a matrix on the display medium layer side, the counter substrate being A display device substrate having a structure having a common electrode facing a pixel electrode on a display medium layer side, wherein the display device substrate has an electrode slit formed in the pixel electrode or the common electrode, and the electrode slit The electrical connection part is also a substrate for a display device, at least one of which is provided in a light shielding region formed from a light shielding structure of a neighboring pixel and a discontinuous light shielding structure.

The present invention further includes an active matrix substrate and a counter substrate facing each other across the display medium layer, the active matrix substrate having pixel electrodes arranged in a matrix on the display medium layer side, and the counter substrate is A display device substrate having a structure having a common electrode facing a pixel electrode on a display medium layer side, wherein the display device substrate has an electrode slit formed in the pixel electrode or the common electrode, and the electrode slit The electrical connection portion is also a display device substrate in which at least one of the electrical connection portions is provided in the light shielding region, and the installation position is marked by the shape of the light shielding structure.

The display device substrate of the present invention includes an active matrix substrate and a counter substrate facing each other with a display medium layer interposed therebetween, and the active matrix substrate has pixel electrodes arranged in a matrix on the display medium layer side, The counter substrate is a substrate used for a display device having a structure having a common electrode facing the pixel electrode on the display medium layer side. As a display device to which such a substrate for a display device is applied, a display type liquid crystal display device in which liquid crystal molecules are aligned and divided by an electrode slit formed in a pixel electrode or a common electrode is preferable. For example, an MVA type liquid crystal display device is used. A display device is preferred. Further, as a method for driving the display device substrate, a dot (DOT) inversion method, a line inversion method, or the like can be used. Further, not only a transmission type but also a reflection type or a reflection / transmission type display device may be used. The display device substrate of the present invention can be applied to a display device having a pixel electrode, for example, an electrophoretic display, in addition to a liquid crystal display device.
The display device substrate of the present invention is used as an active matrix substrate or a counter substrate included in the display device described above. Examples of the active matrix substrate include a TFT (thin film transistor) array substrate, and examples of the counter substrate include a color filter substrate.

The substrate for a display device has an electrode slit formed in a pixel electrode or a common electrode, and an electrical connection part (inter-electrode slit connection part) of the electrode slit includes electrodes divided by the electrode slit. It is preferable to provide a size that can be separated by laser cutting. Here, when the substrate for a display device of the present invention is an active matrix substrate, an electrode slit is formed on the pixel electrode, and when it is an opposing substrate, an electrode slit is formed on the common electrode (counter electrode). Will be.
As the form of the electrical connection portion of the electrode slit, (1) a form provided outside the light shielding area, (2) inside a light shielding area formed from a light shielding structure of a neighboring pixel and a discontinuous light shielding structure (3) There are three forms that are provided in the light-shielding region and that are marked at the installation position by the shape of the light-shielding structure. The display device substrate of the present invention has any one of the electrode slit electrical connection portions in the substrate among the electrode slit electrical connection portions of the above-described forms (1) to (3). What is necessary is just to have an electrical connection part of the electrode slit of multiple forms in a board | substrate. Accordingly, in the present invention, the adjacent pixel and discontinuous light shielding structure in the form (2) and the electrical connection portion of the electrode slit in the form (3) are provided in one pixel. Marks may be mixed. In the present invention, the electrical connection portions of the electrode slits may be mixed inside and outside the light shielding region.
The light shielding region is not particularly limited as long as the transmitted light is blocked. For example, (a) metal wiring formed on the active matrix substrate, (b) formed on the active matrix substrate or the counter substrate. It is preferable that the region be formed from at least one of the light shielding structures among the black matrix and (c) the multi-color stack of color filters formed on the active matrix substrate or the counter substrate. Here, the light shielding region may be formed on the display device substrate of the present invention, or may be formed on the counter substrate when the display device substrate of the present invention is an active matrix substrate. If it is a counter substrate, it may be formed on an active matrix substrate.

In the form of (1) above, the electrode slit connecting portion is provided outside the light shielding region. However, even if the defective portion is cut off, the signal line and the scanning line are not cut, thereby affecting adjacent pixels. Thus, the defect portion can be cut off to be a minute defect, and the influence on the display quality of the pixel electrode which is operating normally after correction is extremely small. As a particularly preferred mode, as shown in FIG. 1-1, when the display device substrate is an active matrix substrate, the display device substrate is provided in a region where there is no metal wiring formed on the substrate.
In the mode (2), the inter-electrode slit connecting portion is disposed under the light shielding structure and the discontinuous light shielding structure of the adjacent pixels. Specifically, for example, as shown in FIG. As described above, there is a mode in which the inter-electrode slit connection portion provided in the region where the metal wiring does not exist is disposed under a light shielding object such as a black matrix. In such a form, light leakage or the like can be prevented. Examples of the light shielding structure (light shielding material) include a metal wiring, a black matrix, and a multicolor overlapping of color filters. In the mode (2), the light shielding region in which the inter-electrode slit connecting portion is provided may be formed of a light shielding material that is discontinuous with the adjacent pixels. The light shielding object and the light shielding object continuous with the adjacent pixels are both present on the substrate. At this time, the adjacent pixel and the discontinuous light shielding object and the light shielding object continuous with the adjacent pixel may be made of the same material or different materials.
In the form of (3) above, the position of the electrode slit connection portion is marked according to the shape of the light shielding structure. This is a case where the electrode slit connection portion is provided in the light shielding region. In addition, it becomes possible to recognize the corrected portion under the light blocking object. The mark according to the shape of the light shielding structure is not particularly limited as long as it is a mark of a correction portion. For example, in addition to the triangular notch shown in the mark 29 in FIG. 7, a triangular protrusion, a rectangular notch Or a projection or the like, or an independent pattern such as a spherical shape. The mark indicating the installation position of the electrode slit connection portion may be formed on a light shielding structure that shields the electrical connection portion of the electrode slit, or may be formed of another member. Also good. As an example in which a mark formed of another member is used, light shielding on the signal wiring is performed by a BM (black matrix) on the CF substrate side, and the position of the electrode slit connecting portion disposed in the light shielding material (BM). An example in which a mark is attached with the shape of the signal wiring on the AM substrate side.
Among these forms, the form (1) is particularly suitable.

Below, the more preferable form in the board | substrate for display apparatuses of this invention is demonstrated.
The display device substrate is preferably an active matrix substrate having a pixel electrode in which an electrode slit is formed. As such an active matrix substrate, a scanning line, a signal line, a switching line is formed on an insulating substrate. The switching element is provided at an intersection where the scanning line and the signal line intersect, and includes a gate electrode connected to the scanning line, and a signal line. A source electrode connected to the drain electrode, and a drain extraction electrode connected to the pixel electrode, and the interlayer insulating film is connected to each of the plurality of capacitor electrodes arranged on the auxiliary capacitor wiring via the insulating layer, and switched. The device has a plurality of contact holes for connecting the drain extraction electrode of the device and the pixel electrode, and the electrode slot extends across the auxiliary capacitance wiring between the contact holes. Form in which bets are formed are preferred.
In such a form, the interlayer insulating film is provided above the signal lines, the scanning lines, and the switching elements, and a contact hole is provided in the interlayer insulating film, and further a pixel electrode is provided above the interlayer insulating film. It becomes. In the present invention, it is preferable that the interlayer insulating film between the signal line and the pixel electrode is sufficiently thick so that the increase in capacitance is reduced even if the signal line and the pixel electrode overlap. As a result, a structure in which the signal line and the pixel electrode overlap with each other can be adopted, and the light shielding film region (light shielding region) that hides the alignment failure around the pixel electrode can be reduced as much as possible.

In the above embodiment, the pixel electrode is connected to the drain wiring extending from the switching element of each pixel by the contact hole, and thereby the drain potential is supplied to the pixel electrode. It is preferable that a plurality of drain extraction electrodes exist in one pixel. The drain extraction electrode is preferably directly connected to the capacitance electrode under the interlayer insulating film. That is, for example, as shown in FIG. 1-1, a structure is used in which a branched drain extraction electrode 5 is used to directly connect a switching element (for example, TFT element) 3 to each auxiliary capacitance electrode 6 under an interlayer insulating film. As a result, when a vertical leak occurs between the switching element 3 and the auxiliary capacitance line 2, even if the corresponding pixel electrode is cut off, the remaining pixel electrodes can be displayed.

In the above embodiment, the contact hole is connected to each of the plurality of capacitor electrodes arranged on the auxiliary capacitor wiring via the insulating layer, and contacts the drain extraction electrode and the pixel electrode of the switching element. . That is, in the above embodiment, there are a plurality of capacitance electrodes formed on the auxiliary capacitance wiring, and contact holes connected to the pixel electrodes are respectively provided on the capacitance electrodes. In the above embodiment, the electrode slit of the pixel electrode is provided across the auxiliary capacitance wiring between at least two of the plurality (two or more) of contact holes. In the specification of the present application, “above” includes the numerical value. In addition, it is preferable that the capacitor electrodes connected to the contact hole have an independent structure. By adopting such a configuration, even if the pixel electrode region connected to the contact hole on one side is separated due to vertical leakage, the other capacitor electrode functions, so the liquid crystal display quality is reduced by the corrected auxiliary capacitor. It can be sufficiently prevented.

In the present invention, when an electrical short circuit occurs due to conductive foreign matter or the like in a part of the pixel electrode in which the electrode slit is formed and a pixel defect occurs, the electrical connection of the electrode slit is performed by a method such as laser irradiation. The pixel defect is corrected by cutting the portion and electrically isolating the region where the electrical short circuit has occurred from other regions. As a result, after the correction, the pixel electrode in which the electrical short circuit has occurred is not connected to the other pixel electrode. A form after such a pixel defect correction, in which the pixel electrodes connected to the contact holes are not connected, is also a preferred form of the present invention.

In the display device substrate of the above aspect, the electrical connection portion of the electrode slit preferably has a structure existing on the drain wiring. Thus, for example, when a vertical leak occurs in the pixel electrode region connected to the drain extraction electrode via the contact hole and it is necessary to separate it, both the drain wiring and the electrode slit connection portion are individually laser Without cutting, the pixel electrode in which the defect has occurred can be separated only by laser cutting the electrode slit connecting portion, and the correction of the pixel defect can be simplified.

It is preferable that the display device substrate of the above embodiment has a structure in which a plurality of signal lines in the vicinity of the electrode slits are arranged in parallel and each of them is partially connected. When the electrode slit connecting portion to be laser cut exists in the vicinity of the signal line, the signal line may be cut simultaneously with the electrode slit connecting portion at the time of laser cutting. For this reason, it is preferable to take measures to secure a detour path of the data signal when the wiring is cut in advance. For example, as shown in FIG. 8, the data signal wiring 4 (signal line) in the vicinity of the correction unit is arranged in parallel. In addition, by connecting each of them partially, even if the wiring 4b on one side of the data signal wiring 4 is cut by laser cutting, it is preferable that the data signal be bypassed by the wiring 4a on the other side. is there. The number of signal lines at the laser cutting target is not particularly limited as long as it is plural, and may be two as shown in FIG. 8, or a larger number may be arranged.

It is preferable that the display device substrate of the above aspect further has a correction structure for supplying the drain potential of the adjacent pixel to the pixel electrode in which the electrode slit is formed. As a correction structure, for example, a pixel connection electrode is installed between adjacent pixels, a correction electrode portion is provided on both adjacent pixels in the upper layer via an insulating layer, and the pixel electrode is provided on the correction electrode portion. And a structure in which a contact hole connected to is provided. Normally, when a vertical leak occurs on a pixel electrode to which a contact hole, which is a source for supplying a drain potential to the pixel electrode, is connected, a signal is not supplied to the remaining pixel electrodes if the corresponding part is cut off. The entire pixel becomes defective. In such a case, for example, as shown in FIG. 9, if a contact structure 32 for connecting adjacent pixels is formed to have a correction structure for supplying the drain potential of the adjacent pixels, When a defect occurs in the pixel electrode connected to the contact hole 8, the pixel electrode is separated by laser cutting, and then intersects between the electrode 33 connected to the contact hole 8a and the electrode 33 between adjacent pixels. By connecting the crossing portion 31 with the wiring 34 arranged in this way by laser irradiation, it becomes possible to supply the remaining pixel electrode with a substantially normal drain potential and to make it function, and sufficiently suppress the deterioration of display quality. be able to.

The display device substrate is preferably a counter substrate having a common electrode in which an electrode slit is formed. Note that the counter substrate is preferably a color filter (CF) substrate. The electrode slit is preferably formed outside the light shielding region. Thus, if the slit shape is prepared in the common electrode (counter electrode) outside the light shielding region, the region can be divided more finely. In such a case, it is preferable that an inter-electrode slit connection portion (divided portion) is provided outside the light shielding region.
The electrical connection portion of the electrode slit may be in the form of (1) to (3) described above. However, for example, as shown in FIG. 4A, the arrangement form surrounds the electrode region 24. It is preferable to do. As a result, when a vertical leak occurs in the electrode region 24, it can be separated by laser-cutting the surrounding slit connection portion 25 that can make the generation site a minimum independent electrode. Since the laser output / wavelength in this case varies depending on the CF film thickness and film quality, it is necessary to adjust the output so that the laser can be cut reliably.
In the above embodiment, when the colored layer is formed on the CF substrate side, if the electrode pattern is on the red colored layer, the energy of the infrared laser is not absorbed in the colored layer. The other colored layers (green, blue, etc.) absorb energy and may be cut off. Therefore, it is preferable to take measures such as arranging a light shielding metal or the like on the substrate (AM substrate) facing the CF substrate to shield the light leakage after the laser cut correction. On the other hand, a display such as a monochrome display device in which the display device substrate of this embodiment is used for X-ray applications, a CFon TFT structure (for example, described in JP 2000-147555 A) or the like that forms a CF pattern on a TFT substrate. When used in an apparatus, it is possible to carry out laser cut correction according to the present invention without problems.

The present invention is also a display device correcting method for correcting an electrical short circuit in the display device substrate, wherein the display device correcting method causes an electrical short circuit between electrodes of an active matrix substrate and a counter substrate. In this case, it is also a method for correcting the display device in which the defective portion is separated by laser irradiation from at least one of the back side of the substrate. Normally, the vertical leak is caused by conductive foreign matter adhering in the TFT process, CF process, and liquid crystal process, and is confirmed by attaching and illuminating the active matrix substrate and the counter substrate. Is irradiated with laser from the back side of one of these substrates, that is, the glass side.
Thus, it is preferable that the portion to be irradiated with laser is the electrode slit connecting portion of the display device substrate of the present invention, and the electrode slit connecting portion around the defective portion is cut by laser irradiation. By separating the defect occurrence location, it is possible to make it difficult to recognize as a defect by making the vertical leak occurrence location a minute defect, thereby preventing the display quality of the display device from being lowered and improving the yield.
In the method for correcting the display device, it is preferable to use a fundamental wave (wavelength: 1064 nm) of an yttrium aluminum garnet (YAG) laser that is infrared (IR) that is more easily transmitted through glass than ultraviolet light.

The present invention further relates to a method of correcting an electrical short circuit in the display device substrate, wherein the display device substrate correction method is performed when an electrical short circuit occurs between the drain extraction electrode and the auxiliary capacitance wiring. In addition, it is a method for correcting a substrate for a display device in which a defective portion is separated from the pixel electrode side of the active matrix substrate by laser irradiation. Note that the display device substrate used in such a correction method is an active matrix substrate. Usually, since an electrical short (D-Cs leak) between the drain extraction electrode and the auxiliary capacitance wiring can identify a defective portion visually in a patterning completion state of the active matrix substrate, in the above correction method, Laser irradiation is performed from the pixel electrode side of the active matrix substrate, that is, the surface opposite to the glass surface.
The location where laser irradiation is performed in this way is not particularly limited as long as the failure occurrence location is cut off. For example, as shown in FIG. 10, the periphery of the pixel electrode on the contact hole 8 ′ where the D-Cs leak is confirmed. The drain lead wiring 5 ′ connected to the contact hole 8 ′ may be laser-cut by cutting 35, but it is preferable to cut the electrode slit connecting portion of the display device substrate of the present invention. Yes, for example, in FIG. 10, it is preferable to cut the connection part 13 between the electrode slits because alignment defects can be sufficiently suppressed.
In the above method for correcting a substrate for a display device, it is preferable to use the fourth harmonic (wavelength 266 nm) of an yttrium aluminum garnet (YAG) laser.

The present invention is a liquid crystal display device comprising the display device substrate, wherein the liquid crystal display device is also a liquid crystal display device that performs alignment division of liquid crystal molecules by electrode slits.
The liquid crystal display device is preferably an MVA type liquid crystal display device, but is not particularly limited as long as it is a display type in which liquid crystal molecules are aligned and divided by electrode slits formed in pixel electrodes. As a driving method of the liquid crystal display device, a dot (DOT) inversion method, a line inversion method, or the like can be used. Moreover, not only a transmission type but also a reflection type or a reflection throwing type display device may be used.
As such a liquid crystal display device, when the display device substrate is used as an active matrix substrate or a counter substrate, vertical leakage, D-Cs leakage, a capacitance electrode formed on an auxiliary capacitance wiring, and a signal line are connected. By making a defect such as an electrical short circuit a minute defect, it can be made difficult to recognize as a defect, display quality is prevented from being deteriorated, and a high yield is produced.

Since the substrate for a display device of the present invention has the above-described configuration, it is difficult to recognize the occurrence of a vertical leak caused by the adhesion of conductive foreign matters as a minute defect, and the high display quality is maintained. In addition, the yield can be improved, and it is possible to cope with a failure mode such as a D-Cs leak or an electrical short circuit between the capacitor electrode formed on the auxiliary capacitor wiring and the signal line. Therefore, it can be suitably used for liquid crystal panels such as large liquid crystal televisions that require high panel quality.

Embodiments of the present invention will be described with reference to the drawings. In the following embodiments, transmissive liquid crystal display devices will be described. However, the present invention is not limited to these embodiments.

(Embodiment 1)
FIG. 2 is a cross-sectional view schematically showing the configuration of the liquid crystal display device 100 according to the first embodiment of the present invention. FIG. 3 shows the shape of the pixel electrode of the active matrix substrate provided in the liquid crystal display device 100 shown in FIG. It is a top view which shows typically.
The liquid crystal display device 100 has a pair of substrates facing each other, and uses a plastic resin bead or a columnar resin structure provided on the color filter substrate 20 or the like as a spacer (not shown) to keep the substrate interval constant. Has been. The liquid crystal display device 100 is an active matrix liquid crystal display device, and includes a color filter substrate 20 and an active matrix substrate 30 having switching elements such as TFTs.

A method for manufacturing the active matrix substrate (AM substrate) 30 will be described below.
A metal such as a Ti / Al / Ti laminated film is formed on the transparent substrate 10 by sputtering, a resist pattern is formed by a photolithography method, dry etching is performed using an etching gas such as a chlorine-based gas, and the resist is formed. By peeling, the scanning signal wiring (gate wiring, scanning line) 1 and the auxiliary capacitance wiring 2 are formed at the same time. Thereafter, a gate insulating film made of silicon nitride (SiNx) or the like, an active semiconductor layer made of amorphous silicon or the like, and a low resistance semiconductor layer made of amorphous silicon or the like doped with phosphorus or the like were formed by chemical vapor deposition (CVD). After that, a metal such as Al / Ti is formed by sputtering, a resist pattern is formed by a photolithography method, dry etching is performed using an etching gas such as a chlorine-based gas, and the resist is peeled off. (Source wiring, signal line) 4, drain lead wiring 5 and auxiliary capacitance forming electrode (auxiliary capacitance electrode) 6 are formed simultaneously. The auxiliary capacitance is formed by sandwiching a gate insulating film of about 4000 mm between the auxiliary capacitance wiring 2 and the auxiliary capacitance forming electrode 6. Thereafter, the source and drain of the low resistance semiconductor layer are separated by dry etching using chlorine gas or the like, and the TFT element 3 is formed. Next, an interlayer insulating film 7 made of acrylic photosensitive resin or the like is applied by spin coating, and a contact hole 8 for electrically contacting the drain lead wiring 5 and the pixel electrode 9 is formed by photolithography. The thickness of the interlayer insulating film 7 is about 3 μm. Further, the pixel electrode 9 and an alignment film (not shown) are formed in this order. This embodiment is an embodiment of an MVA (Multi-domain Vertical Alignment) type liquid crystal display device, and the pixel electrode 9 made of ITO or the like is provided with a slit pattern 11. Specifically, a film is formed by sputtering, a resist pattern is formed by photolithography, and etching is performed with an etchant such as ferric chloride to obtain a pixel electrode pattern as shown in FIG. Thus, the active matrix substrate 30 is obtained.

On the other hand, a color filter substrate (CF substrate) 20 is formed on a transparent substrate 10 with a color filter layer 21 composed of a colored layer of three primary colors (red, green, blue) and a black matrix (BM) 28, and a counter electrode (common). Electrode) 23, an alignment film (not shown), and a protrusion 22 for alignment control.
After applying a negative acrylic photosensitive resin liquid in which fine carbon particles are dispersed by spin coating on the transparent substrate 10, drying is performed to form a black photosensitive resin layer. Then, after exposing a black photosensitive resin layer through a photomask, it develops and forms a black matrix layer (BM). At this time, openings for the first colored layer are respectively formed in regions where the first colored layer (for example, red layer), the second colored layer (for example, green layer), and the third colored layer (for example, blue layer) are formed. The BM is formed so that the opening for the second colored layer and the opening for the third colored layer (each opening corresponds to each pixel electrode) are formed.
Next, after applying a negative acrylic photosensitive resin liquid in which a pigment is dispersed by spin coating to the opening for the first colored layer, drying is performed, and exposure and development are performed using a photomask. A colored layer (red layer) is formed. Then, the color filter layer 21 is completed by forming similarly about a 2nd colored layer (for example, green layer) and a 3rd colored layer (for example, blue layer). Further, a transparent electrode (counter electrode) 23 made of ITO or the like is formed by sputtering, and then a positive type phenol novolac photosensitive resin liquid is applied by spin coating, followed by drying, exposure using a photomask and Development is performed to form vertical alignment control protrusions 22. Thus, the color filter substrate 20 is obtained.

In this embodiment, as shown in FIG. 3, the MVA inter-slit connection part (electric connection part of the electrode slit) 13 is arranged outside the metal wiring (data signal wiring) 4. As a result, even if the defective portion is separated from the pixel electrode 9 by laser irradiation from the back surface of the AM substrate 30, the data signal wiring 4 is not cut, so that the defective portion is separated without affecting the adjacent pixels. It can be. Further, by moving the pixel electrode connection portion 13 out of the metal wiring 4, there is a concern about the alignment failure around the connection portion 13, but the display quality is not particularly affected as a whole pixel. When the pixel electrode connecting portion 13 is cut off, it approaches the original shape of the MVA pixel electrode slit, and therefore the influence on the display quality of the normally operating pixel electrode is minimal after correction.

(Embodiment 2)
FIG. 4-1 is a plan view schematically showing the pixel electrode shape of the CF substrate provided in the liquid crystal display device of Embodiment 2 according to the present invention. In the present embodiment, the present invention is also applicable to a structure in which a vertical alignment protrusion 22 is provided on an electrode of an AM substrate and a slit 11 is provided on an electrode 23 of a CF substrate facing the AM substrate. Indicates adaptability.
In the counter electrode 23 on the CF substrate side in the present embodiment, a pattern of the counter electrode 23 capable of separating the vertical leak occurrence portion is shown in FIG. The slit connecting portion 25 in FIG. 4A is disposed so as to surround the electrode region 24. When a vertical leak occurs in the electrode region 24, the slit connecting portion 25 that can make the generated portion a minimum independent electrode. Can be separated by laser cutting. Since the laser output / wavelength in this case varies depending on the CF film thickness and film quality, it is necessary to adjust the laser output / wavelength so that it can be cut reliably.
In addition, when performing laser cut correction with this structure, a monochrome display device used for X-ray applications or the like, a display device with a CFon TFT (Color Filter on TFT Array) structure having a CF pattern on a TFT substrate, etc. It is possible to make corrections without problems.
However, when the colored layer is formed on the CF substrate side as usual, if the electrode pattern is on the red colored layer, the energy of the infrared laser is not absorbed by the colored layer, so correction by the infrared laser is possible. In the colored layer (green, blue, etc.), the energy of the infrared laser is absorbed, so that it may be cut off. Therefore, it is desirable to take measures such as arranging a light shielding metal on the counter substrate side to shield light leakage after laser cut correction.

(Embodiment 3)
FIG. 5 is a plan view schematically showing the pixel electrode shape of the display device substrate according to Embodiment 3 of the present invention.
When correcting the vertical leak, the electrode connection part is laser-cut from the back side of the substrate with the TFT substrate and the CF substrate bonded together. If metal wiring exists between the connection part and the substrate, the metal wiring is simultaneously There is a risk of cutting. Therefore, the present invention is characterized in that a connection portion is formed outside the metal wiring. In the present embodiment, as shown in FIG. 5, a plurality of contact holes 8 for supplying a drain potential to the pixel electrode 9 are provided. , 8 ′ exist independently on the auxiliary wiring 2, and in the pixel structure in which each is connected to the drain wiring 5 ′, when a vertical leak occurs in the region of the pixel electrode connected to a certain contact hole 8 ′ Then, the drain wiring 5 ′ and the pixel electrode connecting portion 13 ′ connected to the contact hole 8 ′ are separated by laser cutting. In this way, if the pixel electrode connection portion 13 ′ is disposed on the cut portion 26 of the metal wiring that needs to be cut due to the vertical leak, the tact for laser cutting each of the metal wirings is reduced. A pixel electrode connection portion may be disposed on the top.

(Embodiment 4)
FIG. 6 is a plan view schematically showing the pixel electrode shape of the display device substrate according to Embodiment 4 of the present invention.
When correcting the top and bottom leaks, the connection between the electrodes overlaps with a light blocking material such as a black matrix (BM) or metal wiring because the interelectrode connection is laser cut from the back of the substrate with the TFT substrate and CF substrate bonded together. If it is, the target part of laser cut correction will not be visible. Therefore, in the first to third embodiments, a structure in which the inter-electrode connection portion is not disposed under the light shielding material is employed. However, as illustrated in FIG. 6, if the light shielding material 27 is not continuous with the light shielding material of the adjacent pixel. In order to prevent light leakage or the like, it may be arranged at the cut location.

(Embodiment 5)
FIGS. 7A and 7B are plan views schematically showing pixel electrode shapes of the display device substrate according to the fifth embodiment of the present invention.
In the fourth embodiment, it is described that the inter-electrode connection portion 13 may be disposed under the light shielding material (27 in FIG. 6) that is not continuous with the adjacent pixels. However, the light shielding continuous with the light shielding material of the adjacent pixels. Even if the inter-slit connection part 13 is arranged under the object (for example, the black matrix 28), as shown in FIG. 7, the correction part under the light shielding object is recognized by arranging the mark 29 with the light shielding object at the correction part. If it is the structure which made it easy to do, you may take the structure where the connection part 13 between electrode slits overlaps with a light-shielding object. As an example of the pattern of the mark 29, the triangular mark 29 is shown in FIG. 7, but other patterns such as a rectangular shape or a pattern independent of the light shielding object may be used as long as the mark is a mark to be corrected.

(Embodiment 6)
FIGS. 8A and 8B are plan views schematically showing the pixel electrode shape of the display device substrate of Embodiment 6 according to the present invention, and FIG. 8C is a plan view of FIGS. It is sectional drawing which shows typically a cross section when the board | substrate for display apparatuses is cut | disconnected by the AA 'line.
When the electrode slit connection part 13, that is, the laser cutting target portion is present near the signal wiring (for example, the data signal wiring 4), the signal wiring may be cut simultaneously with the electrode slit connection part 13 at the time of laser cutting. Therefore, as shown in FIGS. 8A and 8B, the data signal wiring 4 in the vicinity of the correction portion is arranged in parallel and each of them is partially connected, so that one side of the data signal wiring 4 is cut by laser cutting. Even if the wiring 4b is cut, it is better to have a structure in which the data signal can be bypassed by the other wiring 4a. In FIG. 8, the number of the data signal wirings 4 in the vicinity of the laser cut target portion is two, but a larger number may be arranged.

(Embodiment 7)
FIG. 9 is a plan view schematically showing the pixel electrode shape of the display device substrate according to Embodiment 7 of the present invention.
When a vertical leak occurs on a pixel electrode to which a contact hole that is a drain potential supply source is connected, no signal is supplied to the remaining pixel electrodes when the defective portion is cut off, resulting in a defect in the entire pixel. . Therefore, for example, as shown in FIG. 9, when a contact structure 32 for connecting adjacent pixels is formed, when a defect occurs, the pixel electrode 9 connected to the contact hole 8 is separated by laser cutting. In order to supply a drain potential to the independent pixel electrode 9, a laser is applied to the intersection 31 between the electrode 33 connected to the contact hole 8 a and the wiring 34 arranged to intersect between the electrodes 33 of adjacent pixels. Conducted by irradiation. The electrode 33 under the contact hole 8a and the wiring 34 between the contact holes intersect with each other through an insulating layer. According to the above correction method, even if a failure occurs in the contact hole 8, it is possible to supply a substantially normal drain potential from the adjacent pixel to the remaining pixel electrode so that the contact hole 8 functions. Note that FIG. 9 is an example of the present invention, and any other structure may be used as long as the drain potential can be supplied from the adjacent pixel and the deterioration in display quality due to the arrangement is small.

(Embodiment 8)
FIG. 10 is a plan view schematically showing the pixel electrode shape of the display device substrate according to Embodiment 8 of the present invention. In the present embodiment, a method for correcting a D-Cs leak will be described.
Since the D-Cs leak is a failure mode that occurs between the drain electrode and the auxiliary capacitance wiring, it is possible to identify a defective portion in the patterning completion state on the active matrix substrate side and correct the laser from the film surface side (pixel electrode side). Is possible. As a correction method, as shown in FIG. 10, the periphery 35 of the pixel electrode on the contact hole 8 ′ where the D-Cs leakage is visually confirmed is cut off, and the drain lead wiring 5 ′ connected to the contact hole 8 ′ is removed. Laser cut. As a laser used for correction, for example, a fourth harmonic (wavelength 266 nm) of a YAG laser can be cited. In FIG. 10, the periphery of the electrode is cut in the shape of the correction portion 35, but it is preferable to cut the electrode slit connection portion 13 because there are few alignment defects.

(Other embodiments)
In the first to eighth embodiments, the MVA method is taken as an example, but other display methods that perform alignment division of liquid crystal molecules by electrode slits may be used. Further, other driving methods such as a DOT (dot) inversion method and a line inversion method may be used.

In addition, this application claims the priority based on US Patent Code 35 volume 119 based on the Japan patent application 2004-160115 for which it applied on May 28, 2004. The contents of the application are hereby incorporated by reference in their entirety.

It is sectional drawing which shows typically the pixel electrode shape of the board | substrate for display apparatuses of this invention. It is sectional drawing which shows typically the pixel electrode shape of the board | substrate for display apparatuses used for the conventional liquid crystal display device of a MVA system. It is sectional drawing which shows typically the structure of the liquid crystal display device 100 of Embodiment 1 which concerns on this invention. FIG. 2 is a plan view schematically showing pixel electrode shapes of an active matrix substrate provided in the liquid crystal display device 100 of Embodiment 1 according to the present invention. It is a top view which shows roughly the counter electrode shape of CF board | substrate with which the liquid crystal display device of Embodiment 2 which concerns on this invention is equipped. It is a top view which shows roughly the counter electrode shape of CF board | substrate with which the conventional liquid crystal display device is equipped. It is a top view which shows typically the pixel electrode shape of the board | substrate for display apparatuses of Embodiment 3 which concerns on this invention. It is a top view which shows typically the pixel electrode shape of the board | substrate for display apparatuses of Embodiment 4 which concerns on this invention. (A), (b) is a top view which shows typically the pixel electrode shape of the board | substrate for display apparatuses of Embodiment 5 which concerns on this invention. (A), (b) is a top view which shows typically the pixel electrode shape of the board | substrate for display apparatuses of Embodiment 6 which concerns on this invention, (c) is a display apparatus of (a), (b). It is sectional drawing which shows typically a cross section when a board | substrate is cut | disconnected by the AA 'line | wire. It is a top view which shows typically the pixel electrode shape of the board | substrate for display apparatuses of Embodiment 7 which concerns on this invention. It is a top view which shows typically the pixel electrode shape of the board | substrate for display apparatuses of Embodiment 8 which concerns on this invention.

Explanation of symbols

1: Scan signal wiring (gate wiring)
2: Auxiliary capacitance wiring 3: TFT element (switching element)
4, 4a, 4b: Data signal wiring (source wiring)
5, 5 ': Drain lead wiring 6: Auxiliary capacitance forming electrode 7: Interlayer insulating film 8, 8': Contact hole 9: Pixel electrode 10: Glass 11: Pixel electrode slits 12, 13, 13 ': Connection between electrode slits (Electrical connection of electrode slit)
20: CF (color filter) substrate 21: CF layer 22: Protrusion for alignment control (protrusion for vertical alignment)
23: Counter electrode (common electrode)
24: Counter electrode region 25: Inter-electrode slit connection part (electric connection part of electrode slit)
26: Location to be corrected in Embodiment 3 27: Light shielding film 28 in Embodiment 4: Black matrix 29: Projection (mark) in Embodiment 5
30: AM (active matrix) substrate 31: Modified melt part (intersection of wiring 34)
32: Contact structure (contact hole)
33: Electrode 34: Wiring between contact holes 35: Around the pixel electrode in the contact hole 8 ′

Claims (18)

An active matrix substrate which have a pixel electrodes arranged in a matrix,
The pixel electrode, the electrode slit is formed, are those least one electrical connection of the electrode slit is provided outside the light-blocking region,
The active matrix substrate includes a scanning line, a signal line, a switching element, and an auxiliary capacitance wiring on an insulating substrate, and further includes an interlayer insulating film and a pixel electrode.
The switching element is provided at an intersection where the scanning line and the signal line intersect, and includes a gate electrode connected to the scanning line, a source electrode connected to the signal line, a drain extraction electrode connected to the pixel electrode, Have
The interlayer insulating film has a plurality of contact holes for connecting the drain extraction electrode of the switching element and the pixel electrode,
An active matrix substrate, wherein an electrode slit is formed across the auxiliary capacitance wiring between the plurality of contact holes. 2. The active matrix substrate according to claim 1, wherein the light shielding region is a region formed of a metal wiring. 2. The active matrix substrate according to claim 1, wherein the light shielding region is a region formed of a black matrix. 2. The active matrix substrate according to claim 1, wherein the light shielding region is a region formed from a multi-color overlapping portion of a color filter. The active matrix substrate, the active matrix substrate according to claim 1, wherein the pixel electrodes are connected to the contact hole is equal to or not connected. The active matrix substrate, the active matrix substrate according to claim 1, wherein the drain lead electrode is characterized in that there are a plurality in one pixel. The active matrix substrate, a signal line in the vicinity of the electrode slit is arranged a plurality of parallel to the active matrix substrate according to claim 1, wherein the each of those having a partially connected structure. The active matrix substrate, the active matrix substrate according to claim 1, wherein the pixel electrode where the electrode slit is formed and has a modified structure for supplying a drain potential of the adjacent pixels. A liquid crystal display device comprising the active matrix substrate according to claim 1,
The liquid crystal display device is characterized in that alignment division of liquid crystal molecules is performed by electrode slits. An active matrix substrate and a counter substrate facing each other across the display medium layer,
The active matrix substrate has pixel electrodes arranged in a matrix on the display medium layer side,
The counter substrate has a structure having a common electrode facing the pixel electrode on the display medium layer side.
A display device ,
The pixel electrode, the electrode slit is formed, are those least one electrical connection of the electrode slit is provided outside the light-blocking region,
The active matrix substrate includes a scanning line, a signal line, a switching element, and an auxiliary capacitance wiring on an insulating substrate, and further includes an interlayer insulating film and a pixel electrode.
The switching element is provided at an intersection where the scanning line and the signal line intersect, and includes a gate electrode connected to the scanning line, a source electrode connected to the signal line, a drain extraction electrode connected to the pixel electrode, Have
The interlayer insulating film has a plurality of contact holes for connecting the drain extraction electrode of the switching element and the pixel electrode,
A display device in which an electrode slit is formed between the plurality of contact holes across the auxiliary capacitance wiring. The display device according to claim 10 , wherein the light shielding region is a region formed of a metal wiring formed on an active matrix substrate. The display device according to claim 10 , wherein the light shielding region is a region formed of a black matrix formed on an active matrix substrate or a counter substrate. The display device according to claim 10 , wherein the light shielding region is a region formed from a multicolor overlapping portion of a color filter formed on an active matrix substrate or a counter substrate. The display device according to claim 10 , wherein pixel electrodes connected to contact holes are not connected to the display device substrate. The display device according to claim 10, wherein the display device substrate includes a plurality of drain extraction electrodes in one pixel. 11. The display device according to claim 10, wherein the display device substrate has a structure in which a plurality of signal lines in the vicinity of the electrode slits are arranged in parallel and each of them is partially connected. 11. The display device according to claim 10, wherein the display device substrate has a correction structure for supplying a drain potential of an adjacent pixel to a pixel electrode in which an electrode slit is formed. The display device according to claim 10 , wherein the display device is a liquid crystal display device that performs alignment division of liquid crystal molecules by electrode slits.

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