Display device and method of repairing the same

Abstract

A display device is provided, including: a substrate on which circuit elements constituting pixels are arranged; a repair pattern arranged on the substrate; a buffer layer covering the repair pattern; an active layer arranged on the buffer layer; a conductive layer on which electrodes of the circuit elements are arranged and arranged on the active layer; an outer coating layer covering the conductive layer; and a light emitting element arranged on the outer coating layer, wherein the repair pattern is arranged in a manner that one region thereof overlaps the active layer.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2020-0183263, filed on December 24, 2020, the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0003] This disclosure relates to a display device and a method for repairing the display device. Background Technology

[0004] Display devices consist of a display panel with multiple pixels. If a particular pixel malfunctions, that pixel will not emit light. Therefore, that particular pixel will be seen by the user as a bright spot (bright spot) or a dark spot. In recent years, research has been conducted on pixel structure to repair faulty pixels that may be seen as bright spots (bright spots) or dark spots.

[0005] The above content is only used to help understand the background technology of this disclosure and does not mean that this disclosure falls within the scope of related technologies known to those skilled in the art. Summary of the Invention

[0006] The purpose of this embodiment is to provide a pixel repair structure that stacks repair patterns under an active layer.

[0007] In this structure, when the repair pattern is cut by a laser beam emitted from the outside, cracks propagate to the active layer stacked above the repair pattern. The appearance of cracks causes the active layer to be cut.

[0008] Another objective of the embodiments is to provide a display device capable of separating pixel circuitry with faulty pixels from light-emitting elements by cutting the active layer, and a method for repairing the display device.

[0009] According to one embodiment, a display device is provided, comprising: a substrate having circuit elements disposed for driving pixels; a repair pattern disposed on the substrate; a buffer layer covering the repair pattern; an active layer disposed on the buffer layer; a conductive layer disposed on the active layer and having electrodes of the circuit elements disposed thereon; an outer coating layer covering the conductive layer; and a light-emitting element disposed on the outer coating layer, wherein the repair pattern is arranged such that a region thereof overlaps with the active layer.

[0010] In the display device, the repair pattern may be an isolated electrode formed of a metallic material.

[0011] In the display device, the active layer may be divided into cut-off regions near the opposite ends of the repair pattern.

[0012] In the display device, the active layer may include: a first region overlapping the repair pattern; and a second region adjacent to the opposite end portions of the first region.

[0013] In the display device, the first region and the second region can be separated from each other.

[0014] In the display device, steps may be formed between the first region and each of the second regions.

[0015] In the display device, each circuit element may include: a storage capacitor; a switching transistor that stores a voltage corresponding to a data signal in the storage capacitor in response to a first gate signal; a driving transistor configured to control the amount of driving current applied to the light-emitting element in a manner corresponding to the voltage stored in the storage capacitor; and a sensing transistor configured to sense a feature of the circuit element in response to a second gate signal, wherein the active layer overlapping the repair pattern is an active layer constituting the sensing transistor.

[0016] The display device may further include a light-blocking layer disposed on the same layer as the repair pattern and overlapping with the driving transistor.

[0017] The display device may further include a lower polarizer disposed below the substrate.

[0018] In the display device, the active layer may be formed of indium gallium zinc oxide (IGZO), and the repair pattern may be formed of copper.

[0019] In the display device, the active layer may be formed to have a thickness of 300 angstroms.

[0020] According to another embodiment, a method for repairing a display device is provided, the display device including a substrate on which circuit elements constituting pixels are disposed, a repair pattern disposed on the substrate, a buffer layer covering the repair pattern, an active layer disposed on the buffer layer, a conductive layer disposed on the active layer and having electrodes of circuit elements disposed thereon, an outer coating layer covering the conductive layer, and a light-emitting element disposed on the outer coating layer, wherein a region of the active layer is arranged to overlap with the repair pattern.

[0021] The method may include: inspecting faulty pixels in the display device; and emitting a laser beam toward the repair pattern in the faulty pixels.

[0022] In the method, when the repair pattern is cut by the laser beam, the active layer is cut due to cracks appearing in the buffer layer and the active layer.

[0023] In the method, the active layer may be cut near the opposite ends of the repair pattern.

[0024] In the method, when cutting the active layer, steps are formed on both sides of the cutting area.

[0025] In the method, the laser beam can be in the infrared band.

[0026] By using the display device and the method for repairing the display device according to these embodiments, a laser beam can be used to cut the active layer instead of the conductive layer in the pixel circuitry, thereby repairing faulty pixels.

[0027] When using laser beam cutting to repair faulty pixels, the problem of damage to the insulating layer and light-emitting elements located above the faulty pixels can be solved.

[0028] When using a laser beam to cut the active layer to repair faulty pixels, it can prevent the problem of the lower polarizer being damaged by a laser beam of a specific wavelength used to cut the conductive layer. Attached Figure Description

[0029] The above and other objects, features and other advantages of this disclosure will become clearer from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0030] Figure 1 This is a block diagram illustrating the configuration of a display device according to one embodiment;

[0031] Figure 2 It shows Figure 1 A view of the circuit for an example implementation of the pixels shown;

[0032] Figure 3 This is a view illustrating a method for repairing a display device according to an embodiment;

[0033] Figures 4 to 6 This is a view showing potential display panel damage issues that may occur during pixel repair processing;

[0034] Figure 7 This is a plan view showing the pixel repair structure according to an embodiment;

[0035] Figure 8 It is along Figure 7 A cross-sectional view taken from line I-I' in the diagram;

[0036] Figure 9 and Figure 10 This is a view showing an implementation example of the repaired pixels. Detailed Implementation

[0037] The embodiments will now be described with reference to the accompanying drawings. In this specification, if a constituent element (or region, layer, or portion, etc.) is described as "existing" on, "connected to" or "combined" with different constituent elements, it means that the constituent element can be directly connected / combined with different constituent elements, or a third constituent element can be arranged therein.

[0038] The same reference numerals refer to the same constituent elements. Furthermore, to effectively describe the technical content, the thickness, scale, and dimensions of the constituent elements are exaggerated in the accompanying drawings. The phrase "and / or" is used to include one or more combinations that may be defined by the relevant components.

[0039] The terms "first," "second," etc., can be used to describe various constituent elements, but should not impose any limitations on their meaning. These terms are only used to distinguish one constituent element from another. For example, without departing from the scope of the claimed invention, a first constituent element can be named a second constituent element. Similarly, a second constituent element can be named a first constituent element. Unless explicitly stated in the context, the indefinite article "a" is used to indicate one or more, not just one.

[0040] The terms “below,” “under,” “above,” and “on top,” etc., are used to describe the physical relationships between the constituent elements shown in the accompanying drawings. These terms have relative conceptual meanings and are used with reference to the directions indicated in the accompanying drawings.

[0041] It should be understood that the terms "comprising" and "having," etc., are intended to indicate the presence of the features, quantities, steps, operations, constituent elements, components, or combinations thereof described in this specification. Therefore, it should be understood that these terms do not preclude the possibility of the presence or addition of one or more other features, quantities, steps, operations, constituent elements, components, or combinations thereof.

[0042] Figure 1 This is a block diagram illustrating the configuration of a display device according to one embodiment.

[0043] refer to Figure 1 The display device 1 includes a timing controller 10, a gate driver 20, a data driver 30, a power supply 40, and a display panel 50.

[0044] The timing controller 10 can receive an image signal RGB and a control signal CS from an external source. The image signal RGB can include multiple color level data. As an example, the control signal CS can include a horizontal synchronization signal, a vertical synchronization signal, and a master clock signal.

[0045] The timing controller 10 can process the image signal RGB and the control signal CS in a manner suitable for the conditions of operating the display panel 50, and can generate and output image data DATA, gate drive control signal CONT1, data drive control signal CONT2 and power control signal CONT3.

[0046] The gate driver 20 can generate a gate signal based on the gate drive control signal CONT1 output from the timing controller 10. The gate driver 20 can provide the generated gate signal to the pixel PX through multiple first gate lines GL11 to GL1n.

[0047] The gate driver 20 can provide sensing signals to the pixel PX via multiple second gate lines GL21 to GL2n. These sensing signals can be used to measure the characteristics of the driving transistors and / or light-emitting elements disposed within each pixel PX.

[0048] The data driver 30 can generate a data signal based on the image data DATA output from the timing controller 10 and the data drive control signal CONT2. The data driver 30 can provide the generated data signal to the pixel PX through multiple data lines DL1 to DLm.

[0049] The data driver 30 can provide a reference voltage (or sensing voltage or initialization voltage) to the pixel PX through multiple sensing lines SL1 to SLm, or it can sense the state of the pixel PX based on the electrical signal fed back from the pixel PX.

[0050] Power supply 40 can generate driving voltages for the display panel 50 based on the power control signal CONT3. As an example, the driving voltages may include a high-level driving voltage ELVDD and a low-level driving voltage ELVSS. Power supply 40 can supply the generated driving voltages ELVDD and ELVSS to the pixels PX respectively via corresponding power lines PL1 and PL2.

[0051] A plurality of pixels PX (or subpixels) are arranged in the display panel 50. As an example, the pixels PX may be arranged in a matrix on the display panel 50. The pixels PX may emit light with a brightness corresponding to the data signals provided respectively via data lines DL1 to DLm. In one embodiment, each pixel PX may display one of the colors red, green, and blue, but this disclosure is not limited to these colors.

[0052] The timing controller 10, gate driver 20, data driver 30, and power supply 40 can be configured as separate integrated circuits (ICs), or at least one of these components can be configured to be combined with one or more other components to form an integrated circuit. For example, at least one of the data driver 30 and power supply 40 can be configured to be integrated with the timing controller 10 as an integrated circuit.

[0053] In addition, Figure 1 In the diagram, gate driver 20 and data driver 30 are illustrated as constituent elements separate from display panel 50. However, at least one of gate driver 20 and data driver 30 can be configured integrally with display panel 50 using an in-panel method. For example, gate driver 20 can be integrally formed with display panel 50 using a gate-in-panel (GIP) method.

[0054] Figure 2 It is shown Figure 1 The image shown is a view of the circuitry for an example implementation of the pixels. As an example implementation, Figure 2 The pixel Pxij is shown as being connected to the i-th first gate line GL1i and the j-th data line DLj.

[0055] refer to Figure 2 The pixel PX includes a switching transistor ST, a driving transistor DT, a sensing transistor SST, a storage capacitor Cst, and a light-emitting element LD.

[0056] The first electrode of the switching transistor ST is connected to the data line DLj, and the second electrode is connected to the first node N1. The gate electrode of the switching transistor ST is connected to the first gate line GL1i. When a gate signal at the gate-on level is applied to the first gate line GL1i, the switching transistor ST turns on and transmits the data signal applied to the data line DLj to the first node N1.

[0057] The first electrode of the storage capacitor Cst can be configured to be connected to the first node N1, and the second electrode can be connected to the first electrode (e.g., the anode electrode) of the light-emitting element LD. The storage capacitor Cst can be charged with a voltage corresponding to the difference between the voltage applied to the first node N1 and the voltage applied to the first electrode of the light-emitting element LD.

[0058] The first electrode of the driving transistor DT receives a high-potential driving voltage ELVDD, and the second electrode is connected to the first electrode (e.g., the anode electrode) of the light-emitting element LD. The gate electrode of the driving transistor DT is connected to the first node N1. When a voltage at the gate conduction level is applied through the first node N1, the driving transistor DT is turned on, thereby allowing control of the amount of driving current flowing through the light-emitting element LD in a manner corresponding to the voltage supplied to the gate electrode (i.e., the voltage stored in the storage capacitor).

[0059] The first electrode of the sensing transistor SST is connected to the sensing line SLj, and the second electrode is connected to the first electrode of the light-emitting element LD. The gate electrode of the sensing transistor SST is connected to the second gate line GL2i. When a gate signal at the gate-on level is applied to the second gate line GL2i, the sensing transistor SST turns on and transmits the reference voltage applied to the sensing line SLj to the first electrode of the light-emitting element LD.

[0060] The light-emitting element (LD) outputs light corresponding to the driving current. The LD can be an organic light-emitting diode (OLED) or a micro-inorganic light-emitting diode with micron to nanometer-scale dimensions, but the present invention is not limited to these diodes. The following describes an embodiment where the LD is configured as an organic light-emitting diode.

[0061] The structure of each pixel PX according to this disclosure is not limited to Figure 2 The structure is shown. In one embodiment, each pixel PX may further include at least one element for compensating the threshold voltage of the driving transistor DT or for initializing the voltage of the gate electrode of the driving transistor DT and / or the voltage of the anode electrode of the light-emitting element LD.

[0062] exist Figure 2 The example shown is of a switching transistor ST, a driving transistor DT, and a sensing transistor SST being an NMOS transistor, but this disclosure is not limited to this example. For example, at least one transistor constituting each pixel PX may be configured as a PMOS transistor. In different embodiments, each of the switching transistor ST, the driving transistor DT, and the sensing transistor SST may be implemented as a low-temperature polycrystalline silicon (LTPS) thin-film transistor, an oxide thin-film transistor, or a low-temperature polycrystalline oxide (LTPO) thin-film transistor.

[0063] Figure 3 This is a view illustrating a method for repairing a display device according to an embodiment.

[0064] Figure 3Two pixels, PX(i-1)j and PXij, are arranged adjacent to each other in the first direction DR1. Pixels PX(i-1)j and Pxij are arranged in the j-th pixel column, and thus both are connected to the j-th data line DLj and the j-th sensing line SLj. Furthermore, the first pixel PX(i-1)j is arranged in the (i-1)-th pixel row and is connected to the (i-1)-th gate lines GL1(i-1) and GL2(i-1). The second pixel Pxij is arranged in the ith pixel row and is connected to the ith gate lines GL1i and GL2i.

[0065] refer to Figure 3 The display panel 50 includes a plurality of pixel regions PXA, which are defined in the region where data lines DLj and sensing lines SLj extending along a first direction DR1 intersect with gate lines GL1(i-1), GL1i, GL2(i-1), and GL2i extending along a second direction DR2. Pixels PX(i-1)j and Pxij are arranged in the pixel regions PXA.

[0066] The pixel region PXA may include a light-emitting region EA of a light-emitting element LD in which pixels PX(i-1)j and PXij are arranged, and a non-light-emitting region NEA in which pixel circuitry for driving the light-emitting element LD is arranged.

[0067] A wiring region WA can be defined between adjacent pixel regions PXA along the second direction. Data lines DLj and sensing lines SLj extending along the first direction DR1 are arranged in the wiring region WA. First gate lines GL1(i-1) and GL1i and second gate lines GL2(i-1) and GL2i extend along the second direction DR2 through the non-light-emitting region NEA.

[0068] Data lines DLj, sensing lines SLj, first gate lines GL1(i-1) and GL1i, and second gate lines GL2(i-1) and GL2i are connected to the circuit elements constituting the pixel circuit via contact holes. Specifically, data lines DLj can be connected to the first electrode (e.g., the source electrode) of the switching transistor ST, and sensing lines SLj can be connected to the first electrode (e.g., the source electrode) of the sensing transistor ST. First gate lines GL1(i-1) and GL1i are connected to the gate electrode of the switching transistor ST, and second gate lines GL2(i-1) and GL2i are connected to the gate electrode of the sensing transistor SST.

[0069] In one embodiment, the driving circuit for the light-emitting element LD used to drive the second pixel PXij may malfunction, thus preventing the light-emitting element LD from emitting light properly. To repair the faulty pixel (e.g., the second pixel Pxij), such as... Figure 3As shown, the light-emitting element (LD) of the second pixel PXij can be separated from the driving circuit. Then, the anode electrode of the LD of the second pixel PXij can be connected to the anode electrode of the LD of the adjacent first pixel PX(i-1)j. Then, the driving current of the first pixel PX(i-1)j is applied to the LD of the second pixel PXij. Accordingly, the second pixel PXij can emit light in a manner corresponding to the same data signal as the first pixel PX(i-1)j, and faulty pixels can be repaired.

[0070] Repair processes can be performed using laser beam cutting and laser beam welding. For example, when a laser beam is emitted from the non-emitting region NEA of the second pixel PXij to the pixel circuit, the pixel circuit is damaged, causing it to stop functioning. Subsequently, the anode electrodes of the light-emitting element LD of the first pixel PX(i-1)j and the anode electrodes of the light-emitting element LD of the second pixel PXij can be interconnected by laser beam welding.

[0071] Figures 4 to 6 This shows a view of potential display panel damage issues that may occur during pixel repair processing.

[0072] refer to Figure 4 The display panel 50 may include a substrate 100, a circuit element layer formed on the substrate 100 and including at least one circuit element, and a light-emitting layer including a light-emitting element LD.

[0073] The substrate 100 may be covered by a buffer layer 120. An active layer 130 and a conductive layer, necessary for constructing a transistor, may be formed on the buffer layer 120. The conductive layer may include a gate electrode 151 overlapping the channel region of the active layer 130, and source and drain electrodes respectively connected to the source and drain regions of the active layer 130. In the accompanying drawings, a drain electrode 152 is illustrated as an example. An insulating layer 140 may be inserted between the active layer 130 and the conductive layer. The conductive layer may be covered by a protective layer 160 and an outer coating layer 170.

[0074] The light-emitting element LD is formed on the outer coating 170. The light-emitting element LD may have a structure in which the anode electrode 181, the light-emitting layer 182 and the cathode electrode 183 are stacked on top of each other.

[0075] A lower polarizer 190 can be further disposed below the substrate 100.

[0076] In the display panel 50 described above, laser beam cutting can be performed on the conductive layer when repairing pixels. For example, the laser beam can be emitted from the rear surface of the display panel 50 to the drain electrode 152.

[0077] When a laser beam is emitted onto the drain electrode 152, the drain electrode 152 can be cut. The impact that occurs during the cutting of the drain electrode 152 propagates to the vicinity of the drain electrode 152, thereby inducing cracks in adjacent components. Figure 5 As shown, the cracks that appear at this time may propagate upwards to the insulating layers 160 and 170 and the light-emitting element LD, which may damage the light-emitting element LD.

[0078] In most cases, a laser beam in the infrared band (e.g., with a wavelength of 1064 nm) is used to cut the conductive layer. If a laser beam is used to cut the active layer 130 to repair the pixel PX, then a laser beam in the ultraviolet band (e.g., with a wavelength of 266 nm) is required. Figure 6 As shown, when a laser beam with a narrow wavelength is emitted from below the display panel 50, the laser beam is absorbed by the lower polarizer 190. Therefore, the laser beam does not propagate to the active layer 130, making laser beam cutting difficult. Furthermore, there is a problem that the lower polarizer 190 may be damaged when absorbing the laser beam.

[0079] To address these issues, according to an embodiment, a pixel repair structure is provided that can use a laser beam to cut the active layer 130 to repair pixels PX. The pixel repair structure according to the embodiment will be described in more detail below.

[0080] Figure 7 This is a plan view showing the pixel repair structure according to an embodiment. Figure 8 It is along Figure 7 The cross-sectional view taken by line I-I' in the diagram.

[0081] refer to Figure 7 as well as Figure 1 and Figure 2 The pixel PXij may include a switching transistor ST, a driving transistor DT, a sensing transistor SST, a storage capacitor Cst, and a light-emitting element LD.

[0082] One electrode of the driving transistor DT is connected to the first power supply line PL1, which applies a high-potential driving voltage ELVDD, and the other electrode is connected to the anode electrode 281 of the light-emitting element LD. The gate electrode of the driving transistor DT is connected to one electrode of the storage capacitor Cst.

[0083] One electrode of the switching transistor ST is connected to the data line DLj, and the other electrode is connected to the gate electrode of the driving transistor DT via the storage capacitor Cst. The gate electrode of the switching transistor ST is connected to the first gate line GL1i.

[0084] One electrode of the sensing transistor SST is connected to the sensing line SLj, and the other electrode is connected to the anode electrode 281 of the light-emitting element LD via the other electrode of the driving transistor DT.

[0085] One electrode of the storage capacitor Cst is connected to the gate electrode of the driving transistor DT, and the other electrode is connected to the other electrode of the driving transistor DT.

[0086] The anode 281 of the light-emitting element LD can be connected to another electrode of the driving transistor DT, thereby allowing a driving current to be applied to the anode 281.

[0087] In one embodiment, pixel PXij may include a repair pattern 210. The repair pattern 210 may be arranged to overlap with the active layer 230 of the transistor. For example, the repair pattern 210 may be arranged such that a region of it overlaps with the active layer 230 of the sensing transistor SST. Ideally, in this case, the repair pattern 210 is arranged not to overlap with the conductive layer constituting the transistor.

[0088] The repair pattern 210 can be an electrode in the form of an isolation electrode. There are no particular limitations on the shape and size of the repair pattern 210.

[0089] The stacking structure of the display panel 50 will be described in more detail below.

[0090] refer to Figure 8 The display panel 50 may include a substrate 200, a circuit element layer formed on the substrate 200 and including at least one circuit element, and a light-emitting element layer including a light-emitting element LD.

[0091] The substrate 200 serves as the base component of the display panel 50 and can be a transparent substrate. The substrate 200 can be a rigid substrate formed of glass or tempered glass, or a flexible substrate formed of plastic material.

[0092] A circuit element layer can be formed on the substrate 200, and the circuit element layer can include circuit elements (such as transistors and capacitors, etc.) constituting the pixel PX as well as wiring.

[0093] The repair pattern 210 can be disposed on the substrate 200 as a first conductive layer. The repair pattern 210 can be disposed such that at least one region of it overlaps with the active layer 230. For example, the repair pattern 210 can be disposed such that at least one region of it overlaps with the active layer 230 constituting the sensing transistor SST. The repair pattern 210 can be an island-shaped electrode. There are no particular limitations on the shape and size of the repair pattern 210. However, the repair pattern 210 can have a sufficiently large area overlapping the active layer 230 so that when repairing a pixel, the laser beam emitted to the repair pattern 210 will propagate sufficiently into the active layer 230, thereby generating a crack in the active layer 230.

[0094] A light-blocking layer can be further disposed on the same layer as the repair pattern 210. The light-blocking layer can overlap with the channel region of the active layer constituting the driving transistor DT, thereby protecting the oxide semiconductor device from external light.

[0095] The first conductive layer may be formed of a material selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or may be formed of an alloy of these materials. For example, the first conductive layer may be formed of copper or an alloy whose main component is copper.

[0096] The buffer layer 220 is disposed on the substrate 200 in such a way as to cover the first conductive layer. The buffer layer 220 can prevent ions or impurities from diffusing from the substrate 200 and can prevent water penetration.

[0097] An active layer 230 may be formed on the buffer layer 220. The active layer 230 may be formed of a silicon-based semiconductor material or an oxide semiconductor material. For example, the active layer 230 may be formed of indium gallium zinc oxide (IGZO) as an oxide semiconductor. The active layer 230 may include a source region and a drain region containing p-type or n-type impurities, and a channel formed between the source region and the drain region. In one embodiment, the active layer 230 may be formed very thinly with a thickness of approximately 300 angstroms.

[0098] A region of the active layer 230 may be arranged to overlap with the repair pattern 210. For example, a region of the active layer 230 constituting the sensing transistor SST may overlap with the repair pattern 210.

[0099] Electrodes 251 and 252 of a transistor can be formed on the active layer 230 as a second conductive layer. The gate electrode of the transistor can be arranged to overlap with the channel region of the active layer 230. The source electrode and drain electrode of the transistor can be connected to the source region and drain region of the active layer 230, respectively. As an example, Figure 8The channel region of the active layer 230 overlaps with the gate electrode 251, and the drain electrode 252 is connected to the drain region of the active layer 230.

[0100] In one embodiment, the second conductive layer may be arranged so as not to overlap with the repair pattern 210. Accordingly, when a laser beam is emitted toward the repair pattern 210, the energy of the laser beam can be prevented from propagating to the second conductive layer, or cracks in the active layer 230 can be prevented from propagating to the second conductive layer.

[0101] An insulating layer 240 may be inserted between the active layer 230 and the second conductive layer. The insulating layer 240 may be formed of silicon oxide (SiOx) or silicon nitride (SiNx), or it may be a multilayer formed of these materials.

[0102] The circuit element layer can be covered by a passivation layer 260 and an outer coating layer 270. The passivation layer 260 can be an insulating film for protecting the underlying components, and the outer coating layer 270 can be a planarization film for mitigating steps in the underlying structure. In an embodiment, a color filter (not shown) can be formed between the passivation layer 260 and the outer coating layer 270. The color filter can be formed in the light-emitting region EA. The color filter is a wavelength-selective filter that transmits light in a specific wavelength band and blocks light in another specific wavelength band, selectively transmitting only incident light in a portion of the wavelength band, and can be formed from a photosensitive resin containing a colorant (e.g., pigment or dye). Light passing through the color filter in the light-emitting region EA can be one of red, green, and blue.

[0103] A light-emitting element layer can be formed on the outer coating 270, and the light-emitting element layer includes a light-emitting element LD. The light-emitting element LD includes an anode electrode 281, a light-emitting layer 282, and a cathode electrode 283.

[0104] An anode electrode 281 is formed on an outer coating 270. The anode electrode 281 is connected to the driving transistor DT via a via passing through the outer coating 270 and the passivation layer 260. The anode electrode 281 can be formed of a transparent conductive material, such as indium tin oxide (ITO), indium zinc oxide (IZO), or zinc oxide (ZnO). If the anode electrode 281 is a reflective electrode, then the anode electrode 281 can be formed as three layers: a transparent conductive layer, a reflective layer (metal oxide layer), and a transparent conductive layer. For example, the anode electrode 281 can be formed as three layers comprising ITO / Ag / ITO.

[0105] A light-emitting layer 282 is formed on the anode electrode 281. The light-emitting layer 282 is formed in a manner that covers the anode electrode 281. The light-emitting layer 282 can be formed over a wide area on the display panel 50. The light-emitting layer 282 can have a multilayer thin film structure including a light-generating layer. In this case, the color of the light generated in the light-generating layer can be white, red, blue, green, etc. However, the light is not limited to these colors.

[0106] A cathode electrode 283 can be formed on the light-emitting layer 282. The cathode electrode 283 can be formed over a wide area on the display panel 50. The cathode electrode 283 can be formed of a transparent conductive material (TCO) that can transmit light, or it can be formed of a semi-transmissive conductive material, such as molybdenum (Mo), tungsten (W), silver (Ag), magnesium (Mg), aluminum (Al), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), lithium (Li), calcium (Ca), or alloys of these materials.

[0107] A lower polarizer 290 can be further disposed below the substrate 200.

[0108] Figure 9 and Figure 10 This is a view showing an implementation example of the repaired pixels.

[0109] exist Figure 7 and 8 Faults in pixel PXij can be detected in the display panel 50 shown. Whether a fault has occurred in pixel PXij can be checked through visual inspection (image capture and analysis) and / or electrical inspection (pixel sensing, etc.) of the display panel 50.

[0110] When a fault is detected, laser beam cutting is performed on the active layer 230. For this purpose, a laser beam can be emitted onto the repair pattern 210. The repair pattern 210 is then cut by the laser beam. Figure 9 As shown, the impact occurring during the cutting of the repair pattern 210 propagates upwards to the buffer layer 220 and the active layer 230. Due to this impact, cracks are generated in the buffer layer 220 and the active layer 230. As described above, since the active layer 230 is very thin, with a thickness of approximately 300 angstroms, it can be easily cut. Cutting the active layer 230 interrupts the function of the circuit elements, thereby severing the electrical connection between the faulty pixel circuit and the light-emitting element LD.

[0111] After cutting, as Figure 9 and 10As shown, near the opposite ends of the repair pattern 210, the active layer 230 is divided into cut-off regions. Specifically, the active layer 230 may include a first region A1 disposed above the repair pattern 210 and a second region A2 adjacent to the opposite end portions of the first region A1. Near the opposite end portions of the repair pattern 210, the first region A1 and the second region A2 may be separated from each other. In one embodiment, as... Figure 10 As shown, steps are formed near the opposite ends of the intermediate cut-off regions in the cut-off region, that is, steps appear between the first region A1 and each of the second regions A2.

[0112] In the above embodiment, the repair pattern 210 is cut by emitting a laser beam. The laser beam, operating in the infrared band, can be used to cut the repair pattern 210 formed of metallic material. The wavelength of the laser beam can be approximately 1064 nanometers. The infrared laser beam can propagate directly to the repair pattern 210 without being absorbed by the lower polarizer 290. Therefore, the lower polarizer 290 will not be damaged by the laser cutting.

[0113] The repair pattern 210 is arranged so as not to overlap with the conductive layer on the active layer 230 or the light-emitting element LD. Therefore, vibrations that occur when cutting the repair pattern 210 will not propagate to the light-emitting element LD, thereby preventing damage to the light-emitting element LD.

[0114] While specific embodiments of this disclosure have been described for illustrative purposes, those skilled in the art will understand that various modifications, additions, and substitutions are possible without departing from the scope and spirit of this disclosure as disclosed in the appended claims.

Claims

1. A display apparatus comprising: a substrate on which circuit elements for driving a pixel are arranged; a repair pattern arranged on the substrate; a buffer layer covering the repair pattern; an active layer arranged on the buffer layer; a conductive layer on which electrodes of the circuit elements are arranged and on which the active layer is arranged; an overcoat layer covering the conductive layer; and a light emitting element arranged on the overcoat layer, wherein the repair pattern is arranged in a manner that one region thereof overlaps the active layer. 2.The display apparatus of claim 1, wherein the repair pattern is an electrode in an isolated form, the electrode being formed of a metal material. The active layer is divided into cut-off regions near opposite ends of the repair pattern.

3. The display device of claim 1, wherein, 4.The display apparatus of claim 1, wherein the active layer comprises: a first region overlapping the repair pattern; and second regions arranged adjacent to opposite end portions of the first region, respectively. 5.The display apparatus of claim 4, wherein the first region and the second regions are separated from each other. 6.The display apparatus of claim 5, wherein a step is formed between the first region and each of the second regions. 7.The display apparatus of claim 1, wherein each of the circuit elements comprises: a storage capacitor; a switching transistor configured to store a voltage corresponding to a data signal in the storage capacitor in response to a first gate signal; a driving transistor configured to control an amount of driving current applied to the light emitting element in a manner corresponding to the voltage stored in the storage capacitor; and a sensing transistor configured to sense a characteristic of the circuit element in response to a second gate signal, wherein the active layer overlapping the repair pattern is an active layer constituting the sensing transistor. 8.The display apparatus of claim 7, further comprising: a light blocking layer arranged on the same layer as the repair pattern and arranged to overlap the driving transistor. 9.The display apparatus of claim 1, further comprising: a lower polarizing plate arranged below the substrate. 10.The display apparatus of claim 1, wherein the active layer is formed of indium gallium zinc oxide (IGZO) and the repair pattern is formed of copper. 11.The display apparatus of claim 1, wherein the active layer is formed to have a thickness of 300 angstroms. 12.A method of repairing a display apparatus, the display apparatus comprising a substrate on which circuit elements constituting a pixel are arranged, a repair pattern arranged on the substrate, a buffer layer covering the repair pattern, an active layer arranged on the buffer layer, a conductive layer on which electrodes of the circuit elements are arranged and on which the active layer is arranged, an overcoat layer covering the conductive layer, and a light emitting element arranged on the overcoat layer, one region of the active layer being arranged to overlap the repair pattern, the method comprising: checking a defective pixel in the display apparatus; and emitting a laser beam to the repair pattern in the defective pixel. ​ ​ ​ 13. The method of claim 12, wherein when the repair pattern is cut by the laser beam, the active layer is cut due to cracks occurring in the buffer layer and the active layer.

14. The method of claim 13, wherein the active layer is cut near opposite ends of the repair pattern.

15. The method of claim 14, wherein when the active layer is cut, steps are formed on both sides of the cut area.

16. The method of claim 12, wherein the laser beam is in the infrared wavelength band.

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