KR20060046241A - Liquid crystal display device - Google Patents

Abstract

The unit pixel of the liquid crystal display according to the present invention includes a first substrate and a second substrate; A gate line and a data line intersecting the first substrate to define a unit pixel, and dividing the unit pixel into two first and second pixel units; First and second switching elements respectively provided in the first and second pixel units and receiving the same scan signal; A plurality of first and second common electrodes formed corresponding to the first and second pixel units; A plurality of first and second pixel electrodes formed corresponding to the first and second pixel units; A common line shared by the pixel adjacent to the unit pixel to apply a signal in common; And a liquid crystal layer formed between the first and second substrates.

Liquid crystal display device, first and second pixel portion, first and second switching element, first and second common electrode, first and second pixel electrode, common line, mask, column spacer

Description

Liquid crystal display device {LIQUID CRYSTAL DISPLAY DEVICE}

1 is a typical IPS mode A plan view showing unit pixels of a liquid crystal display device.

2A is a plan view illustrating a unit pixel of a liquid crystal display according to a first exemplary embodiment of the present invention.

FIG. 2B is a sectional view taken along line AA 'of FIG. 2A;

3 is a plan view illustrating a unit pixel of a liquid crystal display according to a second exemplary embodiment of the present invention.

4A is a plan view illustrating a unit pixel of a liquid crystal display according to a third exemplary embodiment of the present invention.

4B is a cross sectional view taken along line B-B 'of FIG. 4A;

5 is a plan view illustrating a unit pixel of a liquid crystal display according to a fourth exemplary embodiment of the present invention.

FIG. 6A to FIG. 6D are process flow charts for the section taken along the line AA ′ of FIG. 2A.

*** Description of the major symbols in the drawings ***

First pixel portion: P1 Second pixel portion: P2

First switching element: 1T1, 2T1, 3T1, 4T1

Second switching element: 1T2, 2T2, 3T2, 4T2

First common electrode: 113P1, 213P1, 313P1, 413P1

Second common electrode: 113P2, 213P2, 313P2, 413P2

First pixel electrode: 115P1, 215P1, 315P1, 415P1

Second pixel electrode: 115P2, 215P2, 315P2, 415P2

Column spacer: 134

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device capable of lowering a defective production rate of a pixel due to a defective switching device, improving aperture ratio, and increasing luminance.

In recent years, with the development of the information society, various types of demands on display devices have increased, such as liquid crystal display (LCD), plasma display panel (PDP), electro luminescent display (ELD), field emission display (FED), and VFD (Vacuum). Research on flat panel display devices such as fluorescent displays is being actively conducted. Among them, liquid crystal display devices (LCDs) have been in the spotlight for high quality, mass production technology, ease of driving means, light weight, thinness, and low power consumption.

The liquid crystal display device is a display device that displays a desired image by individually supplying data signals according to image information to pixels arranged in a matrix, and adjusting light transmittance for each pixel. Active Matrix (AM) method. The active matrix method is a method of adding a switching element such as a thin film transistor (TFT) to each pixel, applying a voltage to the liquid crystal in the pixel portion through the pixel, and driving the liquid crystal.

Such liquid crystal display devices can be classified into liquid crystal display devices having various display modes according to the type of liquid crystal molecules driven. TN (twisted nematic) mode liquid crystal display devices have been mainly used among various display modes.

The TN mode liquid crystal display device turns the electric field in a direction perpendicular to the substrate to drive the liquid crystal molecules such that the director of the liquid crystal has an angle between 0 ° and 90 ° with respect to the substrate. It has the advantages of monochrome display, fast response and low driving voltage.

However, since the TN mode liquid crystal display device drives the liquid crystal molecules perpendicular to the substrate as described above, there is a disadvantage that the viewing angle characteristics are not excellent. That is, the viewing angle dependence in which the screen color or brightness of the image changes depending on the direction or angle of viewing the liquid crystal display device is caused. Therefore, in order to overcome this disadvantage, a new wide viewing angle technology, that is, an in-plane switching (IPS) mode liquid crystal display device in which the liquid crystal is driven while the director of the liquid crystal molecules is horizontal with respect to the substrate has been actively developed in recent years. Is being studied.

The IPS mode liquid crystal display device is a liquid crystal display device that secures a wide viewing angle characteristic compared to the conventional by forming a transverse electric field on the substrate when the voltage is applied to the electrode to align the liquid crystal molecules horizontally. Has been shown.

As shown in the figure, on the thin film transistor substrate of the liquid crystal display device, gate lines 3 and data lines 1 made of metal layers are vertically and horizontally arranged to define unit pixels. In the actual liquid crystal display device, n gate lines 3 and m data lines 1 intersect with n x m pixels. However, only one pixel is shown in the figure for simplicity.

At the intersection of the gate line 3 and the data line 1, a switching element (for example, a thin film transistor) consisting of a gate electrode 4, a semiconductor layer A, and source / drain electrodes 5 and 11 is formed. a film transistor T is formed, and the gate electrode 4 and the source / drain electrodes 5 and 11 are connected to the gate line 3 and the data line 1, respectively, through the gate line 3. The switching element T is turned on as an input signal, and an image signal applied through the data line 1 is transmitted to the pixel.

In addition, a common line 17 transmitting a common signal is arranged in parallel with the gate line 3 in the unit pixel, and at least one pair of electrodes for switching the liquid crystal molecules, that is, the common electrode 13 and the pixel electrode 15. ) Is arranged parallel to the data line 1 to generate an in-plane electric field parallel to the substrate.

In this case, the common electrode 13 is formed simultaneously with the gate line 3 and connected to the common line 17. The pixel electrode 15 is formed simultaneously with the source / drain electrodes 5 and 11 to form a thin film transistor ( It is connected to the drain electrode 5 of T. The pixel electrode line 11 ′ electrically connecting the pixel electrodes 15 overlaps the common line 17, the common line 17, and a gate insulating layer (not shown) between the storage capacitors. (storage capacitor, Cst).

On the other hand, the liquid crystal display device as described above includes one switching device in each pixel, and thus, when a defect occurs in the switching device, the entire unit pixel does not operate normally. This problem is not only limited to IPS mode liquid crystal display devices, but also occurs in liquid crystal display devices driven by vertical electric fields such as TN mode.

Substantially, the thin film transistor used in the liquid crystal display device is formed through a plurality of deposition processes and etching processes, and various defects occur in the process of such a plurality of processes. One of the most fatal defects among the defects of the thin film transistor is a short defect between the gate electrode and the source or drain electrode. When such a thin film transistor defect occurs in an active matrix liquid crystal display device using a large number of thin film transistors, Fatal marking defects appear as point defects in conventional products.

Accordingly, the present invention has been made in view of the above problems, and the unit pixel of the liquid crystal display device is divided into two first and second pixel portions, and the first and second switching elements are separately formed in each pixel portion. The purpose is to exclude the possibility that the entire unit pixel will be defective when a failure occurs in the switching element of.

Other objects and features of the present invention will be described in detail in the configuration and claims of the invention below.

In order to achieve the above object, the liquid crystal display device according to the present invention comprises a first substrate and a second substrate; A gate line and a data line intersecting the first substrate to define a unit pixel, and dividing the unit pixel into two first and second pixel units; First and second switching elements respectively provided in the first and second pixel units and receiving the same scan signal; A plurality of first and second common electrodes formed corresponding to the first and second pixel units; A plurality of first and second pixel electrodes formed corresponding to the first and second pixel units; A common line shared by the pixel adjacent to the unit pixel to apply a signal in common; And a liquid crystal layer formed between the first and second substrates.

In addition, the manufacturing method of the liquid crystal display device according to the present invention comprises the steps of preparing a transparent first substrate; Forming first and second switching devices on the substrate; And forming a column spacer for the black matrix on the first and second switching devices, and the forming of the column spacers may be performed on the entire surface of the substrate on which the first and second switching devices are formed. Applying a film; Irradiating ultraviolet rays by blocking a mask in which a non-transmissive region of light is provided in a region where a pattern is to be left on the organic layer; And developing the organic layer irradiated with ultraviolet rays to form an organic layer pattern positioned on the first and second switching elements.

Hereinafter, the content of the present invention will be described with reference to the drawings of preferred embodiments.

FIG. 2A is a plan view illustrating a unit pixel of a liquid crystal display according to a first exemplary embodiment of the present invention, and FIG. 2B is a cross-sectional view taken along line AA ′ of FIG. 2A, as shown in the drawing. The unit pixel of the liquid crystal display is defined by the intersection of the gate line 103 and the data line 101 on the first substrate 102, and has a structure divided into two parts of the first and second pixel units.

First and second switching elements 1T1 and 1T2 are disposed in the first and second pixel units P1 and P2, respectively, and the same scan signal is provided in the first and second pixel units P1 and P2. Apply. In this case, the first and second switching devices 1T1 and 1T2 form a 1-gate-2- thin film transistor structure. That is, the first and second switching devices 1T1 and 1T2 are formed symmetrically with respect to the gate line 103 and formed as part of the gate line 103 on the first substrate 102. 104, a gate insulating film 106 stacked on the gate electrode 104, a semiconductor layer 107 formed on the gate insulating film 106, an ohmic contact layer 108 formed on the semiconductor layer 107, And first and second electrodes formed on the ohmic contact layer 108 to share the source electrode 105 formed separately from the data line 101, and are spaced apart from each other by a predetermined interval on both sides of the source electrode 105. 2 drain electrodes 111P1 and 111P2, respectively.

As described above, since the first and second switching devices 1T1 and 1T2 of the present invention share the gate electrode 104 and the source electrode 105, the semiconductor layer 107 is formed by the scan signal of the gate line 103. When activated, the same image signal is transferred from the data line 101 to the first and second drain electrodes 111P1 and 111P2 simultaneously through the source electrode 105, and the image signal is transferred to the first and second pixel portions ( P1, P2) respectively. Therefore, the liquid crystal display according to the present invention drives the first and second pixel units P1 and P2 of the unit pixel by using separate switching elements, thereby causing a failure in the first or second switching elements 1T1 and 1T2. The entire unit pixel area, that is, the entirety of the first and second pixel portions P1 and P2 can all be reduced at the same time.

Substantially, a switching device such as a thin film transistor is manufactured through a plurality of deposition processes and etching processes, and various defects may occur during such a plurality of processes. For example, foreign matter may be inserted between the source electrode and the drain electrode to generate an electrical short between the source electrode and the gate electrode, or may cause the drain electrode to short with the neighboring data line. have. In fact, in order to prevent light leakage around the gate line, the drain electrode may be formed to extend in the direction of the data line adjacent to the gate line. In this process, the drain electrode and the neighboring data line are short-circuited due to a process defect. may be short). As such, when the source electrode and the drain electrode, or the drain electrode and the data line are short-circuited, a brightness defect may occur, causing deterioration in image quality of the liquid crystal display. In addition, when a pattern defect occurs in the lower semiconductor layer of the data line, and a semiconductor layer pattern is formed below the pixel electrode, the bright point defect may be generated by adversely affecting the driving of the pixel electrode.

For this reason, in order to solve the problem of bright spot defect, there have been attempts to remove the portion causing the defect by irradiating the laser beam to the region of the pattern in the switching element. However, in order to detect bright spot defects, all pixels in the liquid crystal display are required to be inspected, and when the pattern defects are 2 μm or less, they may not be detected due to a decrease in detection power of the detection equipment. In addition, a separate process of irradiating a laser beam may be added to remove the defective part, which may cause a problem in that the production yield is reduced.

However, in the pixel structure according to the present invention, since the divided pixels receive signals by separate switching elements, the pixel unit in which the switching elements operate normally is operated even when a failure of the switching elements as described above occurs. Can be. That is, the defective area can be reduced only by the failure of one division area of the unit pixel, and as a result, the normal operating pixel area is relatively increased, so that an effect of reducing the probability of being found as a defective pixel when the image is displayed can be obtained. have.

Meanwhile, the first and second pixel electrodes P1 and P2 according to the first exemplary embodiment of the present invention have a stripe shape and are arranged at regular intervals, respectively. And the image signals transmitted from the first and second drain electrodes 111P1 and 111P2 of the first and second switching devices 1T1 and 1T2. Here, the image signal is transmitted through the first and second contact holes 109P1 and 109P2 formed on the upper passivation layer 110 of the first and second switching devices 1T1 and 1T2. The first and second drain electrodes 111P1 and 111P2 of 1T1 and 1T2 are transferred to the first and second pixel electrodes 115P1 and 115P2.

In addition, the first and second common electrodes 113P1 and 113P2 having a stripe shape are formed in the first and second pixel units P1 and P2, respectively, and the first and second pixel electrodes 115P1 and 115P2. Are alternately spaced apart from each other by a predetermined interval to generate a transverse electric field on the first substrate 102 together with the first and second pixel electrodes 115P1 and 115P2. In this case, the common line 117 electrically connected to the first or second common electrodes 113P1 and 113P2 and applying a common signal is disposed at both ends of the unit pixel so as to be adjacent to the first or second common electrode of the pixel unit. Is shared by. That is, the second common electrode 113P2 of the second pixel portion determined by the nth gate line 103 and the first common electrode of the first pixel portion determined by the n + 1th gate line are formed in the boundary region. It is formed separately from the line 117 to receive a common signal. Accordingly, in the liquid crystal display device of the present invention, two common lines are required per three pixels, thereby reducing the number of common lines, thereby increasing the aperture ratio of the liquid crystal display device.

The first common electrode connection line 123P1 and the plurality of first pixel electrodes 115P1, which are parallel to the data line 101 and electrically connect the plurality of first common electrodes 113P1, are formed outside the pixel. Electrically connecting the second common electrode connection line 123P2 and the plurality of second pixel electrodes 115P2 electrically connecting the first pixel electrode connection line 125P1 and the plurality of second common electrodes 113P2 to each other. The second pixel electrode connection line 125P2 is formed to overlap each other with the gate insulating layer 106 and the passivation layer 110 interposed therebetween, thereby forming a storage capacitor.

At this time, the first and second common electrode connection lines 123P1 and 123P2 do not generate an electric field for driving the liquid crystal in the first and second pixel portions P1 and P2, but the signal of the data line 101 The influence on the first and second pixel electrodes 115P1 and 115P2 is shielded. Therefore, the first and second common electrode connection lines 123P1 and 123P2 should be disposed closer to the data line 101 than the pixel electrode connection lines 125P1 and 125P2 to effectively shield the signal of the data line 101. You can.

On the other hand, the first and second pixel electrodes 115P1 and 115P2 are formed by overlapping portions of the gate line 103 adjacent to one side thereof, thereby preventing light leakage near the gate line 103. Through this, the line width of the black matrix on the gate line 103 may be minimized or the black matrix may be substantially removed from the region. In fact, the overlapping structure of the gate line 103 and the pixel electrodes 115P1 and 115P2 minimizes the area of the dielectric existing between the gate electrodes 103 and the pixel electrodes 115P1 and 115P2 to reduce accumulation of DC components. By doing so, afterimage induction due to residual DC components is suppressed. In addition, in the unit pixel of the present invention, since the gate line 103 is disposed on the center line of the pixel instead of the boundary area between two adjacent pixels, both the first and second pixel electrodes 115P1 and 115P2 are the gate lines of the pixel. Overlaid only to 103, and is not affected by variations in the gate line 103 given by adjacent pixels. Accordingly, voltage fluctuation of the pixel electrode due to the corresponding pixel gate signal is reduced, light leakage due to voltage distortion appearing in the boundary region between adjacent pixels is also prevented, and defects such as flicker can be minimized.

Further, in the liquid crystal display according to the present invention, the first and second common electrodes 113P1 and 113P2 and the first and second pixel electrodes 115P1 and 115P2 are disposed between 0 ° and 45 ° with respect to the data line 101. It is formed to have an inclination angle. The direction of the electric field generated by the first common electrode 113P1, the first pixel electrode 115P1, the second common electrode 113P2, and the second pixel electrode 115P2 is substantially different with respect to the data line 101. The inclination angle between 0 ° and 45 ° is provided so that the rubbing direction of the alignment layer can be formed perpendicular to the data line 101. That is, the rubbing direction for inducing the initial arrangement of liquid crystal molecules and the electric field directions formed between the data line 101 and the first and second pixel electrode lines 123P1 and 123P2 in the outer portion of the pixel are processed in the same manner, thereby This allows for horizontal orientation, thereby preventing the liquid crystal molecules, particularly adjacent to the data line 101, from being distorted by the residual voltage even when no voltage is applied. Accordingly, the light leakage phenomenon in the vicinity of the data 101 may be prevented, thereby minimizing the width of the black matrix on the data line 101 or removing the black matrix.

As a result, the liquid crystal display according to the present invention has a structure in which the gate line 103 and the data line are formed through an overlapping structure of the gate line 103 and the first and second pixel electrodes 115P1 and 115P2 and a horizontal alignment structure of the liquid crystal. By preventing light leakage from occurring in the vicinity of 101, the black matrix in the region can be removed, and the luminance and aperture ratio of the liquid crystal display can be improved.

In addition, such a configuration does not require the black matrix on the gate line 103 and the data line 101 as described above, so that only the channel portion of the switching element requires the minimum black matrix, and thus, the first substrate. By forming a column spacer 134 on the 102 or the second substrate 132, the black matrix on the switching element may be replaced. That is, the column spacer 134 is formed to serve as a light shielding function of the black matrix. This not only enables the structure (blackmatrix-free) that can minimize the influence of the margin margin of the conventional black matrix on the liquid crystal display (e.g., reduction of the aperture ratio), but also the formation of the conventional black matrix By eliminating the separate mask process that was required in the step, it reduces the mask process step required for manufacturing the liquid crystal display device.

On the other hand, the second substrate 132 of the present invention, in addition to the color filter layer 136 for realizing the color of the column spacer to prevent the light leakage to the top of the first and second switching elements (1T1, 1T2, etc.) A black matrix double layer 134 may be formed, and first and second alignment layers (not shown) for determining the initial alignment direction of the liquid crystal are formed on opposite surfaces of the first substrate 102 and the second substrate 132, respectively. The liquid crystal layer 150 may be interposed therebetween.

On the other hand, the pixel structure of the first embodiment as described above reduces the defective area by dividing the unit pixels and driving each individually, but still includes the possibility of defective pixels. Accordingly, the second embodiment of the present invention particularly improves this point and provides a liquid crystal display device capable of minimizing the defective rate of pixels. Since the configuration of this embodiment is similar to that of the first embodiment, only differences are described.

3 is a plan view illustrating a unit pixel of a liquid crystal display according to a second exemplary embodiment of the present invention. In the present exemplary embodiment, for the above-described purpose, the first pixel electrode 215P1 and the first pixel of the first pixel portion P1 are formed. The second pixel electrode 215P2 of the two pixel portion P2 is connected to the upper portion of the gate line 203 to be integrally formed. In other words, by electrically connecting the first and second pixel electrodes 215P1 and 215P2, a defect occurs in the first switching element 2T1 or the second switching element 2T2 and is connected to the pixel electrode (first or second). When a signal cannot be applied to the two pixel electrodes 215P1 and 215P2, the pixel electrode which is normally applied with the image signal can share the image signal with the other pixel electrodes.

In such a configuration, in particular, a short circuit failure or the like occurs between the source electrode 205 and the first drain electrode 211P1 or the source electrode 205 and the second drain electrode 211P2. If the two switching elements 2T1 and 2T2 cannot operate normally, another switching element constituting the unit pixel causes both of the first and second pixel electrodes 215P1 and 215P2 to fail, thereby causing a failure in the unit pixel. It is possible to prevent this from occurring and to reduce the possibility of defective pixels.

4A and 4B are cross-sectional views of unit pixels and lines B-B 'of the liquid crystal display according to the third embodiment of the present invention. It provides a liquid crystal display device that can be obtained. Since the configuration and effects of the present embodiment are also similar to those of the first embodiment, the following description will focus on the differences and effects of the characteristic configurations.

As shown in the figure, in the present embodiment, the first and second common electrodes 313P1 and 313P2 formed on the first substrate 302 to have a plate shape, and the first and second common electrodes ( Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), or Indium Zinc Oxide (IZO) or ITZO (Indium Tin Oxide) are formed on the first and second pixel electrodes 315P1 and 315P2 formed to have a plurality of slits on different layers from 313P1 and 313P2. It is formed of a transparent conductor such as Tin Zinc Oxide) or TO (Tin Oxide). The gap between the first common electrode 313P1 and the first pixel electrode 315P1 and the gap between the second common electrode 313P2 and the second pixel electrode 315P2 are formed to be narrower than a cell gap, thereby forming a first substrate ( A fringe field (F), which is a transverse electric field, is generated at the top. At this time, the interval between the slits of the first and second pixel electrodes 315P1 and 315P2 (that is, the width of the first and second pixel electrodes L1) is sufficiently narrow, so that the transverse electric field F generated between both electrodes is formed. By doing so, all liquid crystal molecules (not shown) on the first substrate 302 including the first and second pixel electrodes 315P1 and 315P2 may be substantially operated. Accordingly, the liquid crystal display device of the present embodiment can have a significantly improved transmittance and aperture ratio compared to the liquid crystal display devices of the first and second embodiments.

In addition, as described above, the first and second common electrodes 313P1 and 313P2 are formed in a plate shape, and the gap between the slits (electrode width, L1) of the first and second pixel electrodes 315P1 and 315P2 is defined as the above. It is formed wider than the width L2 of the slit, so that the overlap region between both electrodes is increased, thereby increasing the value of the storage capacitor generated between the gate insulating film 306 and the protective film 310. As a result, the voltage drop ΔVp of the first and second pixel electrodes 315P1 and 315P2 is reduced, thereby obtaining a field strengthening effect.

In addition, the first and second common electrodes 313P1 and 313P2 may be integrally formed on the entire pixel portion of the pixel adjacent to the pixel portions P1 and P2 of the corresponding pixel. That is, the second common electrode 313P2 of the pixel second pixel portion is connected to the first common electrode 313P1 ′ of the neighboring pixel first pixel portion. Accordingly, the common line 317 of the metal layer formed in the boundary region of two neighboring pixels is determined by the second common electrode 313P2 and the n + 1 th gate line of the second pixel portion determined by the n th gate line. The common signal is shared by the first common electrode 313P1 ′ of the first pixel unit to be applied to the first and second common electrodes 313P1 ′ and 313P2. Accordingly, in the liquid crystal display of the present invention, since two common lines are required per three pixels, the number of common lines can be reduced, thereby increasing the aperture ratio of the liquid crystal display.

In this case, the common line 317 may be formed of a separate metal layer, as shown in the drawing, but also, the second common part of the second pixel portion determined by the n-th gate line 103 is formed of a transparent conductor. The first common electrode 313P1 ′ of the first pixel portion determined by the electrode 313P2 and the n + 1 th gate line may be integrally formed.

Meanwhile, in order to prevent the first and second common electrodes 313P1 and 313P2 in the unit pixel from being short-circuited with the corresponding pixel gate line 303, one side of the first and second common electrodes 313P1 and 313P2 may be formed. The gate line 303 is preferably formed at intervals of 10 μm or more.

The first and second pixel electrodes 315P1 and 315P2 are formed so as to overlap each of the upper and lower edges of the gate line 303 positioned at the center line of the pixel to prevent light leakage on the second substrate (not shown). In order to minimize or eliminate the line width of the black matrix (not shown) formed in order to improve the aperture ratio and luminance of the liquid crystal display device. At the same time, the structure of the first and second pixel electrodes 315P1 and 315P2 and the gate line 303 does not overlap with the structure of the first and second pixel electrodes 315P1 and 315P2. It is possible to reduce the dielectric area between the layers), thereby reducing the residual voltage component accumulated in the dielectric, thereby suppressing the afterimage induced by the residual voltage.

In the above structure, since the position of the gate line 303 is not in the boundary region between two adjacent pixels, the first and second pixels formed in the first and second pixel portions P1 and P2 are located in the center line of the pixel. All of the pixel electrodes 315P1 and 315P2 overlap only the gate lines 303 of the corresponding pixel, so that the pixel electrodes 315P1 and 315P2 are not affected by variations in the gate signals given by adjacent pixels. As a result, both of the first and second pixel electrodes 315P1 and 315P2 are affected only by the variation of the corresponding pixel gate line 303, thereby preventing light leakage due to voltage distortion in adjacent boundary areas between pixels. , Defects such as flicker are minimized.

In addition, the other sides of the first and second pixel electrodes 315P1 and 315P2 are respectively overlapped with the common line 317 disposed in the boundary region of the unit pixel so as to minimize the light leakage region. If the overlapping interval between the second pixel electrodes 315P1 and 315P2 and the common line 317 becomes too large, the value of the storage capacitor may be excessively formed, which may cause a problem in that a signal may be delayed by the residual parasitic capacitor. . Accordingly, the first and second pixel electrodes 315P1 and 315P2 may be formed to overlap only some edges of the common line 317.

On the other hand, in the liquid crystal display according to the present embodiment, since the first and second common electrodes 313P1 and 313P2 and the first and second pixel electrodes 315P1 and 315P2 are formed of a transparent conductor such as ITO over the entire surface of the pixel, It is also possible to minimize light leakage that may occur above and below the gate line 303 by minimizing the possibility of rubbing defects.

In addition, the unit pixel according to the third exemplary embodiment is also divided into two first and second pixel units P1 and P2 with respect to the gate line 303 positioned at the center line of the pixel, respectively. A second switching device 3T1 and 3T2 are provided to apply a signal to the first and second pixel electrodes 315P1 and 315P2 through the first and second contact holes 309P1 and 309P2. In this case, the first and second switching devices 3T1 and 3T2 form a 1-gate-2- thin film transistor structure and are formed symmetrically with respect to the gate line 303. In addition, since the first and second switching devices 3T1 and 3T2 share a gate electrode (not shown) and a source electrode 305, when a scan signal is applied to the gate line 303, the image signal may be firstly transmitted. And the second drain electrodes 311P1 and 311P2 to the first and second pixel electrodes 315P1 and 315P2, respectively. Therefore, the liquid crystal display device according to the present embodiment also has the first and second pixel parts P1 and P2 constituting the unit pixel separately by separate switching devices (first and second switching devices 3T1 and 3T2). As a result, when the defect occurs in the first or second switching elements 3T1 and 3T2, the possibility that all the unit pixel regions, that is, the entire first and second pixel portions P1 and P2, become defective at the same time can be reduced.

Next, as a liquid crystal display device according to a fourth exemplary embodiment of the present invention, as shown in FIG. 5, the unit pixel of the present exemplary embodiment includes first and second pixel electrodes 415P1 and 415P2 on the gate line 403. The structure that connected is formed. Since the configuration of this embodiment is similar to that of the third embodiment, only differences are described.

As shown in the drawing, in the present exemplary embodiment, the first pixel electrode 415P1 of the first pixel portion P1 and the second pixel electrode 415P2 of the second pixel portion P2 are disposed above the gate line 403. Connect to form one piece. In other words, by electrically connecting the first and second pixel electrodes 415P1 and 415P2, a defect occurs in the first switching element 4T1 or the second switching element 4T2, and the pixel electrode (first or When the signal cannot be applied to the second pixel electrodes 415P1 and 415P2, the pixel electrode which is normally applied with the image signal can share the image signal with the other pixel electrodes.

In this structure, when one switching element (first or second switching elements 4T1 and 4T2) in the unit pixel cannot operate normally, another switching element constituting the unit pixel is the first and second pixels. By activating both the electrodes 415P1 and 415P2, it is possible to prevent the occurrence of a defect in the unit pixel and to reduce the possibility of the defective pixel.

Meanwhile, in the liquid crystal display device according to the present invention, the first and second switching devices are disposed on the center line of the unit pixel, and the first and second pixel parts are symmetrically formed over the first to fourth embodiments. The signal delay according to the distance between the switching element and the electrode is minimized in the pixel, thereby improving the afterimage phenomenon. In addition, the vertically symmetric electrode structure prevents color shift, thereby realizing excellent screen quality such as high transmittance, high aperture ratio, afterimage property, and wide viewing angle.

In addition, the first and second common electrodes and the first and second pixel electrodes of the present invention may be formed of indium tin oxide (ITO) or indium zinc oxide (IZO) or indium tin zinc oxide (ITZO) or tin oxide (TO). It does not have to be made of a transparent conductor, and in some cases, it may be composed of various members such as using an opaque metal layer.

Hereinafter, a method of manufacturing a liquid crystal display device according to the present invention will be described with reference to the accompanying drawings.

FIG. 6A to FIG. 6I are process flow charts showing the cutting plane of the line AA ′ of FIG. 2A. In the present embodiment, an example in which the light shielding and cell gap maintaining column spacer according to the present invention is formed on the first substrate as the thin film transistor substrate is shown in FIG. Suggesting.

First, as shown in FIG. 6A, a transparent first substrate 102 and a second substrate (not shown) made of glass, quartz, or the like are prepared, and then molybdenum (Mo) is formed on the first substrate 102. Molybdenum alloy (Mo alloy), aluminum (Al), aluminum alloy (Al alloy), titanium (Ti), titanium alloy (Ti alloy), tantalum (Ta), tantalum alloy (Ta alloy), cobalt (Co), cobalt alloy And a first metal material such as (Co alloy), nickel (Ni), nickel alloy (Ni alloy), copper (Cu) or copper alloy (Cu alloy). Thereafter, the gate line (not shown), the gate electrode 104, the first and second common electrodes 113P1 and 113P2 and the common line (not shown) are patterned by using a first mask. Form. Subsequently, an inorganic material such as silicon nitride (SiNx) or silicon oxide (SiOx) is plasma CVD onto the entire surface of the first substrate 102 including the gate electrode 104 and the first and second common electrodes 113P1 and 113P2. The gate insulating film 106 is formed by vapor deposition by a chemical vapor deposition method.

Next, as shown in FIG. 6B, amorphous silicon and n + amorphous silicon are formed on the gate insulating layer 106, and then patterned using a second mask to form the semiconductor layer 107 on the gate electrode 104. And an ohmic contact layer 108. In addition, molybdenum (Mo), molybdenum alloy (Mo alloy), aluminum (Al), aluminum alloy (Al alloy), titanium (Ti), and titanium are disposed on the entire surface of the first substrate 102 including the ohmic contact layer 108. Ti alloy, tantalum (Ta), tantalum alloy (Ta alloy), cobalt (Co), cobalt alloy (Co alloy), nickel (Ni) or nickel alloy (Ni alloy), copper (Cu) or copper alloy ( By depositing a second metal material such as a Cu alloy, and patterning the same using a third mask to define a pixel along the gate line, the pixel being disposed perpendicular to the gate line, and defining the pixel as the first and second pixel portions. Data lines (not shown) divided into (P1, P2), the source electrode 105 and the semiconductor layer 107 formed separately from the data line are disposed at predetermined intervals from the source electrode 105, respectively First and second drain electrodes 111P1 and 111P2 are formed.

Thereafter, as illustrated in FIG. 6C, the low substrate such as benzocyclobutene or acryl is disposed on the entire surface of the first substrate 102 including the source electrode 105 and the first and second drain electrodes 111P1 and 111P2. A protective film 110 is formed by coating a transparent organic material having a dielectric constant. Subsequently, the passivation layer 110 is patterned using a fourth mask to expose portions of the first contact hole 109P1 and the second drain electrode 111P2 exposing a part of the first drain electrode 111P1. Two contact holes 109P2 are formed.

Next, a transparent mask such as indium tin oxide (ITO) or indium zinc oxide (IZO) or indium tin zinc oxide (ITZO) or tin oxide (TO) is deposited on the passivation layer 110, and then a fifth mask is deposited. By using the patterning method, the first and second pixel electrodes 115P1 and 115P2 are formed on the first substrate 102 together with the first and second common electrodes 113P1 and 113P2. In this case, the first and second pixel electrodes 115P1 and 115P2 form first and second switching elements 1T1 and 1T2 through the first and second contact holes 109P1 and 109P2, respectively. It may be connected to the second drain electrodes 111P1 and 111P2 to receive a data signal.

Next, an organic layer for forming a column spacer for maintaining a cell gap using an organic material such as a photosensitive resin on the first substrate 102 on which the first and second pixel electrodes 115P1 and 115P2 and the passivation layer 110 are formed. After depositing (not shown), a sixth mask selectively formed with a transmissive region and a non-transmissive region for light is disposed thereon, and ultraviolet rays are partially irradiated onto the organic layer for column spacer formation through the transmissive region. Subsequently, by developing the column spacer forming organic film irradiated with ultraviolet rays, the column spacer 134 is formed on the first and second switching devices 1T1 and 1T2 as shown in FIG. 6D. In this case, the column spacer 134 not only maintains a cell gap between the first substrate 102 and the second substrate, but also prevents light leakage from occurring on the first and second switching devices 1T1 and 1T2. As a result of the black matrix, the mask process step for forming a separate black matrix can be omitted in the manufacturing of the liquid crystal display device.

Subsequently, although not shown in the drawing, a first alignment layer that determines the initial alignment direction of the liquid crystal is coated and rubbed on the upper part of the resultant on the first substrate 102 as described above, and separately from the manufacture of the first substrate. The color filter layer 136 is formed on the second substrate 132 constituting the second substrate, and a second alignment layer is coated on the color filter layer 136 and then rubbed. In addition, the first substrate 102 and the second substrate 132 are bonded to each other so that the first and second alignment layers face each other, and within the space where the first substrate 102 and the second substrate 132 are joined. The liquid crystal layer 150 is filled to complete the liquid crystal display device.

Meanwhile, the light blocking column spacer according to the present invention may be formed on the second substrate which is the color filter substrate. In this case, a transparent second substrate is prepared first, and R (red), G ( After the color filter layer formed of color filters such as green) and B (blue) is formed, the column spacer is formed in a region on the second substrate corresponding to the first and second switching elements on the first substrate formed by the above-described method. Is formed.

In conclusion, the manufacturing method of the liquid crystal display device according to the present invention does not require a separate mask process for forming a black matrix on the first substrate or the second substrate, the overall manufacturing process of the liquid crystal display device is simplified and Manufacturing costs can also be reduced.

Next, a method of manufacturing a liquid crystal display device according to a third embodiment of the present invention will be described with reference to FIG. 4B.

First, a transparent first substrate 302 and a second substrate (not shown) made of glass or quartz are prepared, and then molybdenum (Mo), molybdenum alloy (Mo alloy), and aluminum are formed on the first substrate 302. (Al), aluminum alloy (Al alloy), titanium (Ti), titanium alloy (Ti alloy), tantalum (Ta), tantalum alloy (Ta alloy), cobalt (Co), cobalt alloy (Co alloy), nickel (Ni ), A first metal material such as nickel alloy (Ni alloy), copper (Cu) or copper alloy (Cu alloy). Thereafter, the gate line 303, the gate electrode (not shown), and the common line 317 are formed by patterning using the first mask. However, at this time, the common line 317 is not formed of the first metal material, but is formed as a transparent conductive material through the first and second common electrodes 313P1 ′ and 313P2 and a second mask process to be described later. It may be formed.

Subsequently, indium tin oxide (ITO) or indium zinc oxide (IZO), indium tin zinc oxide (ITZO), or TO (ITO) is disposed on the entire surface of the first substrate 302 including the gate line 303 and the gate electrode (not shown). After forming a transparent conductive material such as Tin Oxide), first and second common electrodes 313P1 ′ and 313P2 are formed using a second mask. In this case, as described above, the common line 317 may be formed of an integral transparent conductive material on the same layer as the first and second common electrodes 313P1 ′ and 313P2.

Subsequently, an inorganic material such as silicon nitride (SiNx) or silicon oxide (SiOx) is plasma-deposited on the entire surface of the first substrate 302 including the common line 317 and the first and second common electrodes 313P1 ′ and 313P2. The gate insulating film 306 is formed by depositing by a chemical vapor deposition (CVD) method.

Next, after forming amorphous silicon and n + amorphous silicon on the gate insulating film 306, patterning is performed using a third mask, thereby forming a semiconductor layer and an ohmic contact layer on the gate electrode. Molybdenum (Mo), molybdenum alloy (Mo alloy), aluminum (Al), aluminum alloy (Al alloy), titanium (Ti), titanium alloy (Ti) on the entire surface of the first substrate 302 including the ohmic contact layer alloy, tantalum (Ta), tantalum alloy (Ta alloy), cobalt (Co), cobalt alloy (Co alloy), nickel (Ni) or nickel alloy (Ni alloy), copper (Cu) or copper alloy (Cu alloy) After depositing a second metal material such as a pattern, a pattern is formed using a fourth mask, which is disposed perpendicular to the gate line to define a pixel together with the gate line, and defines the pixel as the first and second pixel units P1,. A data line (not shown) divided by P2), a source electrode formed separately from the data line, and first and second drain electrodes disposed on the semiconductor layer and spaced apart from the source electrode by a predetermined distance, respectively.

Thereafter, a protective film 310 is formed by coating a transparent dielectric material having a low dielectric constant such as benzocyclobutene or acryl on the first substrate 302 including the source electrode and the first and second drain electrodes. . Subsequently, the passivation layer 310 is patterned using a fifth mask to form a first contact hole exposing a part of the first drain electrode and a second contact hole exposing a part of the second drain electrode.

Next, a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) or indium tin zinc oxide (ITZO) or tin oxide (TO) is formed on the passivation layer 310, and then a sixth mask The first and second pixel electrodes 315P1 and 315P2 for generating a transverse electric field are formed on the first substrate 302 together with the first and second common electrodes 313P1 ′ and 313P2. In this case, the first and second pixel electrodes 315P1 and 315P2 are connected to the first and second drain electrodes constituting the first and second switching elements through first and second contact holes, respectively, to apply a data signal. I can receive it.

Next, an organic layer for forming a column spacer for maintaining a cell gap by using an organic material such as a photosensitive resin on the first substrate 302 on which the first and second pixel electrodes 315P1 and 315P2 and the protective layer 310 are formed. After depositing (not shown), a seventh mask selectively formed with a transmission region and a non-transmission region for light is disposed thereon, and the ultraviolet rays are partially irradiated onto the spacer forming film through the transmission region. Subsequently, the spacer film is formed on the first and second switching elements by developing the organic film for spacer formation irradiated with ultraviolet rays. In this case, the spacer not only maintains a cell gap between the first substrate 302 and the second substrate, but also prevents light leakage from occurring on the first and second switching devices, thereby serving as a black matrix. As a result, in the manufacture of the liquid crystal display device, the mask process step for forming a separate black matrix can be omitted.

Subsequently, a first alignment layer that determines the initial alignment direction of the liquid crystal is coated and rubbed on the resultant on the first substrate 302 as described above, and on the second substrate constituting the liquid crystal panel separately from the manufacture of the first substrate. A color filter layer is formed, and a second alignment layer is coated on the color filter layer and then rubbed. The first substrate 302 and the second substrate are bonded to each other so that the first and second alignment layers face each other, and the liquid crystal layer is filled in the separation space where the first substrate 302 and the second substrate are bonded to each other. Complete the liquid crystal display device.

Meanwhile, the light shielding spacer according to the present invention may be formed on the second substrate which is the color filter substrate. In this case, a transparent second substrate is prepared first, and R (red) and G (green) are formed on the second substrate. After the color filter layer composed of color filters such as B) and blue (B) is formed, a spacer is formed in a region on the second substrate corresponding to the first and second switching elements on the first substrate formed by the above-described method. .

The embodiments described above are illustrated to illustrate the present invention, but do not limit the scope of the present invention. Although not shown in the drawings, the present invention includes various modes, pixel structures, arrangements and manufacturing methods of the liquid crystal display.

Accordingly, the scope of the invention should be determined by the appended claims rather than by the foregoing description.

As described above, according to the present invention, by dividing and driving the unit pixels of the liquid crystal display device, the possibility of defective production of pixels is reduced, and the electrode structure is formed up and down symmetrically to prevent color shift and to prevent afterimages. Improve.

In addition, the light shielding area on the gate line and the data line is minimized through the overlapping structure of the gate line and the pixel electrode and the horizontal alignment structure of the liquid crystal, thereby improving luminance and aperture ratio.

In addition, by forming the black matrix at the height of the column spacer only on the upper portion of the switching element, and removing the black matrix completely in the other parts, the number of mask process is reduced during the manufacturing process, the effect of the margin margin of the conventional black matrix (margin area) Minimize.

Claims (40)

A first substrate and a second substrate; A gate line and a data line intersecting the first substrate to define a unit pixel, and dividing the unit pixel into two first and second pixel units; First and second switching elements respectively provided in the first and second pixel units and receiving the same scan signal; A plurality of first and second common electrodes formed corresponding to the first and second pixel units; A plurality of first and second pixel electrodes formed corresponding to the first and second pixel units; A common line shared by the unit pixels adjacent to the unit pixels and commonly applying a signal; And And a liquid crystal layer formed between the first and second substrates. The liquid crystal display of claim 1, wherein the first and second switching elements are formed by sharing a gate electrode, a source electrode, and a semiconductor layer. The liquid crystal display of claim 2, wherein the gate electrode is formed as part of one gate line. The liquid crystal display of claim 2, wherein the source electrode is formed separately from one data line. The liquid crystal display device of claim 2, wherein the first switching device further comprises a first drain electrode, and the second switching device further comprises a second drain electrode. The liquid crystal display of claim 1, wherein the first and second pixel units are symmetrically formed with respect to the gate line. The display device of claim 1, wherein the first common electrode and the first pixel electrode are alternately disposed to generate a transverse electric field in the first pixel portion, and the second common electrode and the second pixel electrode are alternately disposed to form the first common electrode. A transverse electric field is generated in the two pixel portion. 8. The transverse electric field of claim 7, wherein the first common electrode, the first pixel electrode, and the second common electrode and the second pixel electrode generate a transverse electric field having an inclination angle of substantially 0 ° to 45 ° with respect to the data line. Liquid crystal display device characterized in that. The liquid crystal display device of claim 8, further comprising an alignment layer on the first and second substrates to induce an initial alignment of the liquid crystal. 10. The liquid crystal display device according to claim 9, wherein the rubbing direction of the alignment layer is formed perpendicular to the data line. The liquid crystal display of claim 1, wherein each of the first and second pixel electrodes overlaps some edge of the gate line. The liquid crystal display of claim 1, wherein the first and second pixel electrodes overlap each other at edges of the common line adjacent to each other. The method of claim 1, wherein the common line is formed in a boundary area between adjacent unit pixels, and the common line is formed of the second common electrode of the unit pixel determined by the nth gate line and the unit pixel determined by the n + 1 th gate line. A liquid crystal display device characterized by simultaneously applying a common signal to the first common electrode. The liquid crystal display device of claim 13, wherein the common line is formed of a metal layer. The liquid crystal display of claim 1, further comprising a black matrix in a region on the first substrate or the second substrate corresponding to the first and second switching elements. 16. The liquid crystal display device according to claim 15, wherein the black matrix is a column spacer. The liquid crystal display of claim 16, wherein a black matrix is not formed in a region on the first substrate or the second substrate corresponding to the gate line and the data line. The method of claim 1, further comprising: a first common electrode connection line electrically connecting the plurality of first common electrodes and a second common electrode connection line electrically connecting the plurality of second common electrodes. A liquid crystal display device. 19. The method of claim 18, further comprising a first pixel electrode connection line electrically connecting the plurality of first pixel electrodes and a second pixel electrode connection line electrically connecting the plurality of second pixel electrodes. A liquid crystal display device. 20. The display device of claim 19, wherein the first common electrode connection line and the first pixel electrode connection line overlap each other to form a first storage capacitor, and the second common electrode connection line and the second pixel electrode connection line overlap each other. A liquid crystal display device comprising forming a storage capacitor. The liquid crystal display of claim 1, wherein the first and second pixel electrodes are connected to an upper portion of the gate line. The display device of claim 1, wherein the first and second common electrodes are formed in a plate shape on the first substrate, and the first and second pixel electrodes are different from the first and second common electrodes. And a plurality of slits on the layer. 23. The liquid crystal of claim 22, wherein the interval between the slits is narrow enough to generate an electric field between the first common electrode, the first pixel electrode, and the second common electrode and the second pixel electrode. Display element. The liquid crystal of claim 23, wherein a distance between the first common electrode and the first pixel electrode and a distance between the second common electrode and the second pixel electrode are smaller than a distance between the first substrate and the second substrate. Display element.  25. The transverse electric field of claim 24, wherein the first common electrode, the first pixel electrode, and the second common electrode and the second pixel electrode generate a transverse electric field having an inclination angle of substantially 0 ° to 45 ° with respect to the data line. Liquid crystal display device characterized in that.  26. The liquid crystal display device according to claim 25, further comprising an alignment film for inducing initial alignment of the liquid crystal on the first and second substrates. 27. The liquid crystal display device according to claim 26, wherein the rubbing direction of the alignment layer is formed perpendicular to the data line. The liquid crystal display of claim 24, wherein the first pixel electrode and the second pixel electrode are connected to an upper portion of the gate line. The liquid crystal display of claim 22, wherein the first and second common electrodes and the first and second pixel electrodes are all formed of a transparent conductor. The method of claim 22, wherein the common line is formed in a boundary area between adjacent unit pixels, and the common line is formed by the second common electrode and the n + 1 th gate line of the unit pixel determined by the n-th gate line. And a transparent conductor integral with the first common electrode. The liquid crystal display device of claim 1, wherein the second substrate further comprises a color filter. Preparing a first substrate and a second substrate; Forming a first metal material on the first substrate; Patterning the first metal material using a first mask to form a gate line, a gate electrode, a common electrode, and a common line; Forming a gate insulating film, amorphous silicon, and n + amorphous silicon on the entire surface of the first substrate; Patterning amorphous silicon and n + amorphous silicon using a second mask to form a semiconductor layer and an ohmic contact layer; Forming a second metal material on the first substrate; Patterning the second metal material using a third mask to form a data line, a source electrode, and first and second drain electrodes; Forming a protective film on the entire surface of the first substrate; Patterning the passivation layer using a fourth mask to form a contact hole; Forming a transparent conductive material on the protective film; And And forming a pixel electrode by patterning the transparent conductive material using a fifth mask. 33. The method of claim 32, further comprising: forming an organic layer on the pixel electrode; And forming a spacer by patterning the organic layer using a sixth mask. 33. The method of claim 32, further comprising forming a liquid crystal layer between the first substrate and the second substrate. Preparing a first substrate and a second substrate; Forming a first metal material on the first substrate; Patterning the first metal material using a first mask to form a gate line, a gate electrode, and a common line; Forming a transparent conductive material on the first substrate; Patterning the transparent conductive material using a second mask to form a common electrode; Forming a gate insulating film, amorphous silicon, and n + amorphous silicon on the first substrate; Patterning amorphous silicon and n + amorphous silicon using a third mask to form a semiconductor layer and an ohmic contact layer; Forming a second metal material on the first substrate; Patterning the second metal material using a fourth mask to form a data line, a source electrode, and first and second drain electrodes; Forming a protective film on the entire surface of the first substrate; Patterning the passivation layer using a fifth mask to form a contact hole Forming a transparent conductive material on the protective film; And forming a pixel electrode by patterning the transparent conductive material using a sixth mask. 36. The method of claim 35, further comprising: forming an organic layer on the pixel electrode; And forming a spacer by patterning the organic layer using a sixth mask. 36. The method of claim 35, further comprising forming a liquid crystal layer between the first substrate and the second substrate. Preparing a first substrate and a second substrate; Forming a first metal material on the first substrate; Patterning the first metal material using a first mask to form a gate line and a gate electrode; Forming a transparent conductive material on the first substrate; Patterning the transparent conductive material using a second mask to form a common line and a common electrode; Forming a gate insulating film, amorphous silicon, and n + amorphous silicon on the first substrate; Patterning amorphous silicon and n + amorphous silicon using a third mask to form a semiconductor layer and an ohmic contact layer; Forming a second metal material on the first substrate; Patterning the second metal material using a fourth mask to form a data line, a source electrode, and first and second drain electrodes; Forming a protective film on the entire surface of the first substrate; Patterning the passivation layer using a fifth mask to form a contact hole; Forming a transparent conductive material on the protective film; And patterning the transparent conductive material using a sixth mask to form a pixel electrode. 39. The method of claim 38, further comprising: forming an organic layer on the pixel electrode; And forming a spacer by patterning the organic layer using a sixth mask. 39. The method of claim 38, further comprising forming a liquid crystal layer between the first substrate and the second substrate.

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