Display device for preventing lateral leakage current

Abstract

A display device according to the present invention comprises: a substrate including a plurality of sub-pixels; a transistor provided in each of the sub-pixels; a bank layer surrounding the plurality of sub-pixels; a first pattern and a second pattern, the first pattern and the second pattern being disposed on the bank layer; and a light emitting device including a first electrode disposed between the bank layers in the sub-pixel, an organic layer on the first electrode, and a second electrode on the organic layer, and wherein the first electrode is disposed between the bank layers in the sub-pixel, the second electrode extends from an upper surface of the organic layer to an upper surface of the first pattern and side surfaces of the first pattern and the second pattern.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202411838341.6, titled "Display Device for Preventing Lateral Leakage Current", filed on December 13, 2024.

[0002] Cross - reference to related applications

[0003] This application claims the benefit of priority to Korean Patent Application No. 10 - 2023 - 0189647, filed in Korea on December 22, 2023, the entire contents of which are hereby incorporated by reference in their entirety. Technical field

[0004] The present invention relates to a display device capable of preventing lateral leakage current. Background art

[0005] With the development of information technology, various types of small and thin display devices have been proposed, such as liquid crystal display devices, organic light - emitting display devices, plasma display devices, micro - LED display devices, etc. These display devices are applied to various electronic devices, such as smartphones and tablet computers.

[0006] In a display device, a display element including an organic light - emitting layer and various electrodes is formed. In this display device, there is a problem that if moisture from the outside penetrates into the display, the electrodes will corrode or the organic light - emitting layer will deteriorate.

[0007] In order to manufacture high - resolution display devices recently, it is necessary to minimize the distance between sub - pixels. However, in this case, as the distance between adjacent sub - pixels decreases, a lateral leakage current is generated between adjacent sub - pixels, and this lateral leakage current causes unwanted light emission from the pixels. The lateral leakage current causes unwanted light emission from the pixels, which becomes a major cause of display device defects. Summary of the invention

[0008] An object of the present invention is to provide a display device capable of preventing lateral leakage current between adjacent sub - pixels by forming an organic layer in each sub - pixel and disconnecting the organic layer between adjacent sub - pixels.

[0009] To achieve this object, a display device according to the present invention includes: a substrate including a plurality of sub-pixels; a transistor disposed in each sub-pixel; a bank layer surrounding the plurality of sub-pixels; a first pattern and a second pattern disposed on the bank layer; and a light-emitting device including a first electrode disposed in the sub-pixel between the bank layers, an organic layer on the first electrode, and a second electrode on the organic layer, and wherein the second electrode extends from the upper surface of the organic layer to the upper surface of the first pattern and the side surfaces of the first pattern and the second pattern.

[0010] The width of the first pattern may be less than the width of the second pattern to form an undercut shape, and the first pattern may be formed of a material having orthogonality, and the second pattern may be formed of a photoresist. In particular, the first pattern may be formed of a fluorine-containing polymer material that contains a large amount of fluorine (F) in a functional group while continuously forming carbon-carbon bonds in a chain structure.

[0011] The second electrode may be integrally formed throughout the sub-pixel.

[0012] The light-emitting device further includes a third electrode on the organic layer between the second electrodes, and the third electrode may be formed of a semi-transparent material or a metal.

[0013] An organic pattern and a conductive pattern are disposed on the second pattern. The organic pattern may be disconnected from the organic layer through the undercut shapes of the first pattern and the second pattern, and the conductive pattern may be disconnected from the third electrode through the undercut shapes of the first pattern and the second pattern.

[0014] An auxiliary electrode is disposed between the first pattern and the second pattern and is electrically connected to the second electrode. The auxiliary electrode may be formed of the metal.

[0015] A encapsulation layer is disposed above the light-emitting device, and a color filter layer is disposed above the encapsulation layer.

[0016] A method of manufacturing a display device according to the present invention includes: providing a substrate including a plurality of sub-pixels; forming a transistor in each of the plurality of sub-pixels; forming a first electrode in each of the plurality of sub-pixels; forming a bank layer surrounding the sub-pixels; depositing an orthogonal material and a photoresist over the entire area of the substrate; developing the photoresist to form a first pattern; using the first pattern as a mask to over-etch the orthogonal material to form a second pattern, the first pattern and the second pattern being formed in an undercut shape; using the first pattern and the second pattern in the undercut shape as masks to deposit an organic material over the substrate to form an organic layer in each of the sub-pixels and an organic pattern on the second pattern; heat-treating the first pattern and the second pattern; and forming a second electrode over the entire area of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic block diagram of an organic light emitting display device according to the present invention.

[0018] Figure 2 is a schematic block diagram of a sub-pixel of an organic light emitting display device according to the present invention.

[0019] Figure 3 is a circuit diagram conceptually showing a sub-pixel of an organic light emitting display device according to the present invention.

[0020] Figure 4 is a plan view schematically showing a sub-pixel of a display device according to the present specification.

[0021] Figure 5 is a cross-sectional view of a display device according to a first embodiment of the present invention.

[0022] Figures 6A to 6I is a view showing a method of manufacturing a display device according to a first embodiment of the present invention.

[0023] Figure 7A and Figure 7B are respectively Figure 6F region A of Figure 6H and an enlarged cross-sectional view of region B of

[0024] Figure 8 is a cross-sectional view of a display device according to a second embodiment of the present invention.

[0025] Figure 9 is a cross-sectional view of a display device according to a third embodiment of the present invention.

[0026] Figure 10 is Figure 9 an enlarged cross-sectional view of region C of

[0027] Figures 11A to 11E It is a view of a method for manufacturing a display device according to a third embodiment of the present invention. Detailed implementation manners

[0028] The advantages and features of the present disclosure and the methods for achieving them will be apparent from the embodiments described in detail below with reference to the accompanying drawings. However, the present disclosure can be implemented in many different forms and should not be construed as limited to the embodiments set forth herein, and the embodiments are provided so that the present disclosure will be thorough and complete, and the scope of the present disclosure will be fully conveyed to those skilled in the art to which the present disclosure pertains, and the present disclosure is only defined by the scope of the appended claims.

[0029] The shapes, dimensions, ratios, angles, quantities, etc. disclosed in the accompanying drawings for describing the embodiments of the present disclosure are illustrative, and thus the present disclosure is not limited to the problems shown. Throughout the present disclosure, the same reference numerals refer to the same components. In addition, in the following description of the present disclosure, when it is determined that the detailed description of the known related art unnecessarily confuses the gist of the present disclosure, the detailed description thereof will be omitted herein. When terms such as "including", "having", "comprising", etc. mentioned in the present disclosure are used, other parts can be added unless the term "only" is used herein. When a component is expressed in the singular, it includes the plural unless otherwise stated.

[0030] When analyzing components, the error range is construed as being included even if there is no explicit description.

[0031] When describing the positional relationship, for example, when the positional relationship between two parts is described as "on", "above", "below", "adjacent to", etc., unless "tight" or "direct" is used, one or more other parts can be located between the two parts.

[0032] When describing the time relationship, for example, when the time precedence relationship is described as "after", "subsequent", "adjacent to", "before", etc., unless "tight" or "direct" is used, discontinuous cases can also be included.

[0033] Although terms such as first, second, etc. are used to describe various components, these components are not essentially limited by these terms. These terms are only used to distinguish one component from another. Therefore, within the technical spirit of the present disclosure, the first component described below can essentially be the second component.

[0034] When describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only used to distinguish an element from other elements, and the nature, order, or quantity of the element is not limited by the terms. When a component is described as "coupled" or "connected" to another component, the component may be directly coupled or connected to the other component, but without special description, it is indirectly coupled or connected to the other component. It should be understood that other components may be "inserted" between each component that is connected or can be connected.

[0035] As used herein, the term "device" may include display devices such as liquid crystal modules (LCMs) (which include display panels and driving units for driving the display panels) and organic light emitting display modules (OLED modules). In addition, the term "device" may also include notebook computers, televisions, computer monitors, vehicle electronic devices including devices for vehicles or other types of vehicles, and setting electronic devices or setting devices such as mobile electronic devices like smart phones or electronic tablets, which are finished products (complete products or final products) including LCMs and OLED modules.

[0036] Accordingly, the device in the present invention may include display devices themselves such as LCMs, OLED modules, etc., application products including LCMs, OLED modules, etc., or setting devices for devices for end users.

[0037] Hereinafter, the present disclosure will be described in detail with reference to the accompanying drawings.

[0038] The present invention can be applied to various display devices. For example, the display device of the present invention can be applied to various display devices such as organic light emitting display devices, liquid crystal display devices, electrophoretic display devices, quantum dot display devices, micro LED (light emitting device) display devices, and micro LED display devices. However, in the following description, for the sake of explanation, an organic light emitting display device will be described as an example.

[0039] The present invention will be described in detail below with reference to the accompanying drawings.

[0040] Figure 1 is a schematic block diagram of a display device 100 according to the present invention, and Figure 2 is Figure 1 a schematic block diagram of a sub-pixel SP shown.

[0041] As Figure 1 shown, the organic light emitting display device 100 includes an image processing unit 102, a timing control unit 104, a gate driving unit 106, a data driving unit 107, a power supply unit 108, and a display panel 109.

[0042] The image processing unit 102 outputs the image data supplied from the outside and drive signals for driving various devices. For example, the drive signals from the image processing unit 102 may include a data enable signal, a vertical synchronization signal, a horizontal synchronization signal, and a clock signal.

[0043] The image data and drive signals are provided from the image processing unit 102 to the timing control unit 104. The timing control unit 104 writes and outputs a gate timing control signal GDC for controlling the drive timing of the gate drive unit 106 and a data timing control signal DDC for controlling the drive timing of the data drive unit 107 based on the drive signals from the image processing unit 102.

[0044] The gate drive unit 106 outputs a scan signal to the display panel 109 in response to the gate timing control signal GDC provided from the timing control unit 104. The gate drive unit 106 outputs the scan signal through a plurality of gate lines GL1 to GLm. In this case, the gate drive unit 106 may be formed in the form of an integrated circuit (IC) (but is not limited thereto). The gate driver 106 includes various gate drive circuits, and the gate drive circuits may be directly formed on the substrate 110. In this case, the gate driver 106 may be a gate-in-panel (GIP) in the panel.

[0045] The data drive unit 107 outputs a data voltage to the display panel 109 in response to the data timing control signal DDC input from the timing control unit 104. The data drive unit 107 samples and latches the digital data signal DATA provided from the timing control unit 104 to convert it into an analog data voltage based on the gamma voltage. The data drive unit 107 outputs the data voltage through a plurality of data lines DL1 to DLn. In this case, the data drive unit 107 may be mounted on the upper surface of the display panel 109 in the form of an integrated circuit (IC) (but is not limited thereto).

[0046] The power supply unit 108 outputs a high potential voltage VDD, a low potential voltage VSS, etc., to supply them to the display panel 109. The high potential voltage VDD is supplied to the display panel 109 through the first power supply line EVDD, and the low potential voltage VSS is supplied to the display panel 109 through the second power supply line EVSS. At this time, the voltage from the power supply unit 108 is applied to the data drive unit 107 or the gate drive unit 106 to drive them.

[0047] The display panel 109 displays an image based on the data voltage from the data drive unit 108, the scan signal from the gate drive unit 106, and the power from the power supply unit 108.

[0048] The display panel PAN includes a plurality of sub-pixels SP for displaying an image. The sub-pixels SP may include red sub-pixels, green sub-pixels, and blue sub-pixels. In addition, the sub-pixels SP may include white sub-pixels, red sub-pixels, green sub-pixels, and blue sub-pixels. The white sub-pixels, red sub-pixels, green sub-pixels, and blue sub-pixels may be formed in the same area or may be formed in different areas.

[0049] As Figure 2 shown, a sub-pixel SP may be connected to a gate line GL1, a data line DL1, a first power supply line EVDD, and a second power supply line EVSS. The sub-pixel SP may include a plurality of thin film transistors and a storage capacitor, depending on the configuration of the pixel circuit. For example, the sub-pixel SP may include two transistors and one capacitor (referred to as 2T1C), but is not limited thereto. The sub-pixel SP may be composed of 3T1C, 4T1C, 5T1C, 6T1C, 7T1C, 3T2C, 4T2C, 5T2C, 6T2C, 7T2C, 8T2C, etc.

[0050] Figure 3 is a circuit diagram showing the sub-pixel SP of the organic light emitting display device 100 according to the present invention.

[0051] As Figure 3 shown, the organic light emitting display device 100 according to the present invention includes a gate line GL, a data line DL, and a power supply line PL that cross each other to define the sub-pixel SP. A switching thin film transistor Ts, a driving thin film transistor Td, a storage capacitor Cst, and a light emitting device D are provided in the sub-pixel SP.

[0052] The switching thin film transistor Ts is connected to the gate line GL and the data line DL, and the driving thin film transistor Td and the storage capacitor Cst are connected between the switching thin film transistor Ts and the power supply line PL. The light emitting device D is connected to the driving thin film transistor Td.

[0053] In the organic light emitting display device having such a structure, when the switching thin film transistor Ts is turned on according to the gate signal applied to the gate line GL, the data signal applied to the data line DL is applied to the gate electrode of the driving thin film transistor Td and one electrode of the storage capacitor Cst through the switching thin film transistor Ts.

[0054] The driving thin film transistor Td is turned on according to the data signal applied to the gate electrode. Therefore, a current proportional to the data signal is supplied from the power supply line PL to the light emitting device D through the driving thin film transistor Td, and then the light emitting device D emits light with a brightness proportional to the current flowing through the driving thin film transistor Td.

[0055] At this time, the storage capacitor Cst is charged with a voltage proportional to the data signal to keep the voltage of the gate electrode of the driving thin film transistor Td constant for one frame.

[0056] In the drawings, only two thin film transistors Td and Ts and one capacitor Cst are provided, but the present invention is not limited thereto. Three or more thin film transistors and two or more capacitors may be provided in the present invention.

[0057] Figure 4 is a view showing a pixel PIX of the display device 100 according to the present invention.

[0058] The display device 100 according to the present invention includes a plurality of pixels PIX, and each pixel PIX may include a plurality of sub-pixels SP1, SP2, and SP3. For example, the first sub-pixel SP1 may be a green sub-pixel that emits green light, the second sub-pixel SP2 may be a red sub-pixel that emits red light, and the third sub-pixel SP3 may be a blue sub-pixel that emits blue light. However, it is not limited thereto. The first sub-pixel SP1 may be a red sub-pixel or a blue sub-pixel, the second sub-pixel SP2 may be a green sub-pixel or a blue sub-pixel, and the third sub-pixel SP3 may be a green sub-pixel or a red sub-pixel. In addition, the pixel PIX may include a white sub-pixel that emits white light.

[0059] Although the sub-pixels SP1, SP2, and SP3 may be formed in an S stripe shape in which the third sub-pixel SP3 is vertically arranged and the first sub-pixel SP1 and the second sub-pixel SP2 are horizontally arranged, the sub-pixels SP1, SP2, and SP3 may also be formed in a strip shape, a triangle shape, or a diamond shape.

[0060] In the drawings, the size of the first sub-pixel SP1 is the smallest, the size of the second sub-pixel SP2 is medium, and the size of the third sub-pixel SP3 is the largest. However, the sizes of the first to third sub-pixels SP1, SP2, and SP3 may all be the same. In addition, the size of the first sub-pixel SP1 may be the largest, and the size of the third sub-pixel SP3 may be the smallest. Thus, in the present invention, the first to third sub-pixels SP1, SP2, and SP3 may be formed in various sizes as needed.

[0061] A bank layer BNK is formed around the sub-pixels SP1, SP2, and SP3. The bank layer BNK is arranged to surround each of the sub-pixels SP1, SP2, and SP3 to divide the sub-pixels SP1, SP2, and SP3. In other words, it can be said that a plurality of openings exposed to the outside are formed in the bank layer BNK, and the sub-pixels SP1, SP2, and SP3 are defined in each opening.

[0062] The bank layer BNK can be formed of a single layer, but may also be formed of multiple layers. For example, the bank layer BNK can be formed of two layers, a hydrophilic lower bank layer and a hydrophobic upper bank layer thereon. In this case, the width of the lower bank layer is wider than the width of the upper bank layer, such that the lower bank layer and the upper bank layer form a stepped structure, but is not limited thereto.

[0063] The light-emitting devices D1, D2, and D3 can be disposed in each of the sub-pixels SP1, SP2, and SP3. For example, the light-emitting devices D1, D2, and D3 can be white light-emitting devices that output white light.

[0064] Although not shown in the drawings, each of the light-emitting devices D1, D2, and D3 can include a first electrode, a second electrode, and an organic layer disposed therebetween. The first electrode can be an anode electrode. The first electrode is disposed in each of the sub-pixels SP1, SP2, and SP3 and is electrically disconnected from the first electrodes of adjacent sub-pixels. A data voltage can be applied from an external data driving unit to the first electrode.

[0065] The organic layer is formed in the sub-pixels SP1, SP2, and SP3 and can be separated from the organic layers of adjacent sub-pixels. That is, the organic layer is formed in the first to third sub-pixels SP1, SP2, and SP3, but these organic layers are disconnected at the boundaries of the first to third sub-pixels SP1, SP2, and SP3.

[0066] The second electrode can be a cathode electrode. The second electrode can be integrally formed in the entire area of the display device 100. A low voltage VSS can be supplied from an external power source to the second electrode.

[0067] In the present invention, the gap d between adjacent sub-pixels SP1, SP2, and SP3 can be minimized to achieve high resolution and increase the aperture ratio of the sub-pixels SP1, SP2, and SP3. To this end, the present invention reduces the gap d between the sub-pixels SP1, SP2, and SP3 while blocking the current flow path between adjacent sub-pixels SP1, SP2, and SP3 to minimize the lateral leakage current in the adjacent sub-pixels SP1, SP2, and SP3 caused by the reduction of the gap d.

[0068] In particular, in the present invention, the organic layer serving as the flow path of the lateral current is only formed in the sub-pixels SP1, SP2, and SP3, and the organic layer is disconnected between adjacent sub-pixels SP1, SP2, and SP3. Therefore, the lateral leakage current to adjacent sub-pixels can be blocked. In the present invention, the organic layer is formed in the entire area of the sub-pixels SP1, SP2, and SP3 in a single process, but the organic layer is disconnected between the sub-pixels SP1, SP2, and SP3, thereby simplifying the process of the organic layer and simultaneously blocking the inflow of the lateral current.

[0069] Figure 5 It is a cross-sectional view of the structure of a sub-pixel of the display device 100 according to the first embodiment of the present invention. In fact, the display device 100 according to the first embodiment of the present invention includes first to third sub-pixels SP1, SP2, and SP3 that display different colors. However, since the first to third sub-pixels SP1, SP2, and SP3 have substantially the same structure, for the sake of convenience of explanation, only two adjacent sub-pixels SP1 and SP2 are shown in the drawings.

[0070] As Figure 5 shown, a buffer layer 142 is formed on the substrate 140. The substrate 140 can be made of a hard material, such as glass or plastic material, but is not limited thereto. For example, the plastic material may include polyimide, polymethyl methacrylate, polyethylene terephthalate, polyethersulfone, and polycarbonate.

[0071] When the substrate 140 is made of polyimide, the substrate 140 may be made of a plurality of polyimide layers, and an inorganic layer may also be provided between the polyimide layers, but is not limited thereto.

[0072] The buffer layer 142 may be formed in the entire area of the substrate 140 to enhance the adhesion between the substrate 140 and the layers thereon. In addition, the buffer layer 142 may block various types of defects, such as alkaline components flowing out of the substrate 140. In addition, the buffer layer 142 may delay the diffusion of moisture or oxygen infiltrating into the substrate 140.

[0073] The buffer layer 142 may be a single layer made of silicon oxide (SiOx) or silicon nitride (SiNx) or a multi-layer thereof. When the buffer layer 142 is made of a multi-layer, SiOx and SiNx may be alternately formed. The buffer layer 142 may be omitted based on the type and material of the substrate 140, the structure and type of the thin film transistor, etc.

[0074] A thin film transistor is formed on the buffer layer in each of the sub-pixels SP1 and SP2. For the sake of convenience of description, only the driving thin film transistor among various thin film transistors that can be provided in the display area AA is shown, but other thin film transistors, such as switching thin film transistors, may also be included. In the drawings, a thin film transistor with a top gate structure is shown, but the thin film transistor is not limited to this structure and may be formed in other structures, such as a thin film transistor with a bottom gate structure.

[0075] The thin film transistor includes a semiconductor pattern 112 provided on the buffer layer 142, a gate insulating layer 144 covering the semiconductor pattern 112, a gate electrode 114 on the gate insulating layer 144, an interlayer insulating layer 146 covering the gate electrode 114, and a source electrode 115 and a drain electrode 116 on the interlayer insulating layer 146.

[0076] The semiconductor pattern 112 can be made of polycrystalline semiconductor. For example, the polycrystalline semiconductor can be made of low-temperature polycrystalline silicon (LTPS) having a high mobility, but is not limited thereto.

[0077] The semiconductor pattern 112 can be made of oxide semiconductor. For example, the semiconductor pattern 112 can be made of one of IGZO (indium gallium zinc oxide), IZO (indium zinc oxide), IGTO (indium gallium tin oxide), and IGO (indium gallium oxide), but is not limited thereto. The semiconductor pattern 112 includes a channel region 112a in a central region and a source region 112b and a drain region 112c of doped layers on both sides of the channel region 112a.

[0078] The gate insulating layer 144 can be formed over the entire region of the substrate 140 or only over a partial region of the substrate 140. The gate insulating layer 144 can be composed of a single layer or multiple layers made of an inorganic material such as SiOx or SiNx, but is not limited thereto.

[0079] The gate electrode 114 is made of metal. For example, the gate electrode 114 can be formed of a single layer or multiple layers made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu) or an alloy, but is not limited thereto.

[0080] The interlayer insulating layer 146 can be made of an organic material such as photoacrylic, or the interlayer insulating layer 146 can be formed of a single layer or multiple layers made of an inorganic material such as SiOx or SiNx, but is not limited thereto. In addition, the interlayer insulating layer 146 can be formed of multiple organic material layers and inorganic material layers, but is not limited thereto.

[0081] The source electrode 115 and the drain electrode 116 are formed of a single layer or multiple layers made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu) or an alloy, but is not limited thereto. The source electrode 115 and the drain electrode 116 can contact the source region 112b and the drain region 112c of the semiconductor through contact holes formed in the gate insulating layer 144 and the interlayer insulating layer 146, respectively.

[0082] Although not shown in the figure, a bottom shield metal layer can be provided on the substrate 140 under the semiconductor pattern 112. The bottom shield metal layer minimizes a backchannel phenomenon caused by charges trapped in the substrate 140 to prevent afterimages or deterioration of transistor performance. The bottom shield metal layer can be composed of a single layer or multiple layers made of titanium (Ti), molybdenum (Mo), or an alloy thereof, but is not limited thereto.

[0083] A planarization layer 148 is formed on a substrate, and thin film transistors are disposed in the planarization layer 148. The planarization layer 148 may be formed of an organic material such as acrylic acid, but is not limited thereto. The planarization layer 148 may include a plurality of layers including an inorganic layer and an organic layer.

[0084] Light emitting devices D are disposed in each of the sub-pixels SP1 and SP2 on the planarization layer 148. The light emitting device D includes a first electrode 132, an organic layer 134, and a second electrode 136.

[0085] The first electrode 132 is disposed on the planarization layer 148 and is electrically connected to the drain electrode 116 of the thin film transistor through a contact hole formed in the planarization layer 148. The first electrode 132 may be formed of at least one of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof. In addition, the first electrode 132 may be formed of a transparent metal oxide material such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0086] When the display device 100 is a top emission type display device, the first electrode 132 may further include an opaque conductive material layer to serve as a reflective electrode for reflecting light. When the display device 110 is a bottom emission type display device, the first electrode 132 may be made of a transparent conductive material such as ITO or IZO.

[0087] A bank layer BNK is formed at the boundary between the sub-pixels SP1 and SP2 on the planarization layer 148. The bank layer 152 may be a barrier wall that defines the sub-pixels SP1 and SP2. The bank layer BNK divides each sub-pixel to prevent light output of a specific color from an adjacent pixel from being mixed and output.

[0088] The bank layer BNK is formed to surround the sub-pixels SP1 and SP2 (see Figure 4 ), and an opening area OPEN where the first electrode 132 is exposed to the outside may be formed between the sub-pixels SP1 and SP2.

[0089] The bank layer BNK is made of at least one material of an inorganic insulating material such as SiNx or SiOx, an organic insulating material such as benzocyclobutene, acrylic resin, epoxy resin, phenolic resin, polyamide resin, or a photosensitizer including a black pigment, but is not limited thereto.

[0090] A first pattern 162 and a second pattern 164 are formed on the bank layer BNK. The first pattern 162 may be formed of a material having orthogonality, and the second pattern 164 may be formed of a photoresist.

[0091] Orthogonality means that different structures formed inside the display device 100 have different properties. For example, since a specific layer inside the display device 100 has completely different properties from other layers, materials with orthogonality have little influence on other materials.

[0092] In addition, orthogonality can be understood as the property that two objects exist independently regardless of each other. For example, materials with orthogonality can be hydrophobic with low affinity for water and oleophobic with low affinity for oil.

[0093] Since the first pattern 162 has orthogonality, no chemical substances are generated between the first pattern 162 and other layers, and no physical damage to other layers occurs when patterning the first pattern 162. In the present invention, as an orthogonal material, a fluorine-containing polymer material containing a large amount of fluorine (F) in the functional group can be used, while continuously forming carbon-carbon bonds in a chain structure, but it is not limited thereto.

[0094] Since the width of the first pattern 162 is smaller than the width of the second pattern 164, an undercut structure with a reverse step is formed at the boundary between the first pattern 162 and the second pattern 164.

[0095] An organic layer 134 is formed on the upper surface of the first electrode 132, which is exposed to the outside through the opening region OPEN of the bank layer BNK. In addition, an organic pattern 134a is formed on the upper surface of the second pattern 164. As will be described in detail later, the organic layer 134 and the organic pattern 134a are integrally formed by the same process, but the organic layer 134 and the organic pattern 134a are disconnected by the undercut structures of the first pattern 162 and the second pattern 164.

[0096] In other words, although the organic material is deposited in the entire area of the substrate 140, since the organic layer 134 and the organic pattern 134a are disconnected from each other due to the undercut structures of the first pattern 162 and the second pattern 164, the organic layer 134 formed in each sub-pixel SP1 and SP2 is disconnected from the organic layers 134 of adjacent sub-pixels SP1 and SP2. Therefore, it is possible to prevent the lateral current from flowing through the organic layer 134 to adjacent sub-pixels SP1 and SP2.

[0097] For example, the organic layer 134 can be an organic light-emitting layer. In addition, the organic layer 134 can be an inorganic light-emitting layer, a nano-sized material layer, a quantum dot layer, a micro-LED light-emitting layer, or a mini-LED light-emitting layer, but it is not limited thereto.

[0098] When the organic layer 134 is an organic light-emitting layer, the organic layer 134 is formed of a blue organic light-emitting layer and a yellow fluorescent layer to emit white light. In addition, the organic layer 134 may be formed in a multi-stack structure. For example, when the organic layer 134 is formed in a three-stack structure, the first to third stacks may be arranged with two charge generation layers therebetween. Each of the first to third stacks may be formed of an organic light-emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer. For example, the organic light-emitting layer of the first stack may emit red light, the organic light-emitting layer of the second stack may emit blue light, and the organic light-emitting layer of the third stack may emit green light.

[0099] The third electrode 135 is disposed on the organic layer 134, and the conductive pattern 135a is formed on the organic pattern 134a above the second pattern 164. The third electrode 135 and the conductive pattern 135a are made of the same material and formed by a single process, but are disconnected due to the undercut structure of the first pattern 162 and the second pattern 164. When the display device 100 is a top-emission type, the third electrode 135 and the conductive pattern 135a may be made of a translucent conductive material that transmits light. For example, the third electrode 135 may be made of at least one or more of alloys such as LiF / Al, CsF / Al, Mg:Ag, Ca / Ag, Ca:Ag, LiF / Mg:Ag, LiF / Ca / Ag, or LiF / Ca:Ag.

[0100] When the display device 100 is a bottom-emission type, the third electrode 135 may be a reflective electrode made of an opaque conductive material. For example, the third electrode 135 may be made of at least one or more of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof.

[0101] The second electrode 136 is disposed on the third electrode 135. At this time, the second electrode 136 is integrally formed in the entire area of the display device 100. That is, the second electrode 136 extends from the upper surface of the third electrode 135 of the sub-pixels SP1 and SP2 to the upper surface of the conductive pattern through the side surfaces of the bank layer BNK, the first pattern 162, the second pattern 164, the organic pattern 134a, and the conductive pattern 135a.

[0102] The second electrode 136 may be formed of a transparent metal oxide, such as indium tin oxide ITO or indium zinc oxide IZO, but is not limited thereto.

[0103] The third electrode 135 and the conductive pattern 135a are disconnected from each other through the undercut structures of the first pattern 162 and the second pattern 164, but the second electrode 136 is not disconnected through the undercut structures of the first pattern 162 and the second pattern 164. This is because the degree of the reverse step difference of the undercut structures of the first pattern 162 and the second pattern 164 when forming the third electrode 135 and the conductive pattern 135a is different from the degree of the reverse step difference when forming the second electrode 136.

[0104] When forming the third electrode 135 and the conductive pattern 135a, the degree of the reverse step between the first pattern 162 and the second pattern 164 is relatively large, such that the third electrode 135 and the conductive pattern 135a are disconnected from each other. On the other hand, when forming the second electrode 136, the degree of the reverse step between the first pattern 162 and the second pattern 164 is relatively small, such that the second electrode 136 is not disconnected at the boundary between the sub-pixels SP1 and SP2. This will be described in detail later.

[0105] The third electrode 135 and the second electrode 136 form a cathode electrode. Since the cathode electrode includes the third electrode 135 made of a metal and the second electrode 136 made of a metal oxide, the following effects can be obtained.

[0106] Compared with the second electrode 136 made of a metal oxide, the third electrode 135 made of a metal has a relatively high conductivity. Therefore, an image signal is applied to the entire area of the display device 100 through the third electrode 135 provided in the sub-pixels SP1 and SP2 without signal delay to the organic light-emitting device D.

[0107] In addition, since the third electrodes 135 provided in the sub-pixels SP1 and SP2 are electrically connected to each other through the second electrode 136, the cathode electrode is integrally formed above the entire display device 100, and thus an image signal can be applied to the entire area of the display device 100.

[0108] An encapsulation layer 180 is formed above the second electrode 136 of the light-emitting device D. When the light-emitting device D is exposed to impurities such as moisture or oxygen, a pixel shrinkage phenomenon in which the light-emitting area decreases or defects such as dark spots in the light-emitting area may occur. In addition, the moisture or oxygen penetrating into the light-emitting device D oxidizes the metal electrode. The encapsulation layer 180 blocks impurities (such as oxygen and moisture) from the outside to prevent defects in the light-emitting device D and various electrodes.

[0109] The encapsulation layer 180 may be formed of a first encapsulation layer 182a, 182b, and 182c, a second encapsulation layer 184, and a third encapsulation layer 186, but is not limited thereto. The encapsulation layer 180 may be formed of two layers or four layers or more layers.

[0110] The first encapsulation layer 182 and the third encapsulation layer 186 may be made of an inorganic material such as SiOx or SiNx, but are not limited thereto. The second encapsulation layer 184 may be made of an organic insulating material such as an acrylic resin, an epoxy resin, a polyimide, polyethylene, or silicon oxycarbide (SiOC), but is not limited thereto. In addition, the third encapsulation layer 186 may be made of a thin metal (surface-sealing metal), but is not limited thereto.

[0111] The color filter layers CF1 and CF2 are formed on the encapsulation layer 180. Each of the color filter layers CF1 and CF2 may include R, G, and B color filters formed in each sub-pixel SP1 and SP2. The color filter layers CF1 and CF2 transmit only the light of corresponding wavelengths from the light-emitting device D and absorb light of other wavelengths to display R, G, and B colors.

[0112] Although not shown in the figure, the color filter layers CF1 and CF2 may include a W color filter layer that transmits white light. By forming the W color filter layer, the brightness of the display device 100 can be increased.

[0113] Therefore, in the present invention, colors can be achieved by disposing the color filter layers CF1 and CF2 on the encapsulation layer 180. In addition, by absorbing a part of the external light incident from the outside into the display device 100 and re-absorbing a part of the external light reflected inside the display device 100, the reflectance of the external light can be greatly reduced. Therefore, visibility can be improved by reducing the reflectance without having a separate polarizing plate in the display device 100.

[0114] When the display device 110 is a bottom-emitting type display device, the color filter layers CF1 and CF2 may be disposed below the light-emitting device D. For example, the color filter layers CF1 and CF2 may be formed on the interlayer insulating layer 146 or the gate insulating layer 144.

[0115] The protection member 190 is disposed on the color filter layers CF1 and CF2 and is attached by an adhesive (not shown in the figure). The protection member 190 is used to protect the display device 100 and may be formed of glass or a transparent film. As such a film, a transparent protective film such as a PS (polystyrene) film, a PE (polyethylene) film, a PEN (polyethylene naphthalate) film, or a PI (polyimide) film may be used.

[0116] As described above, in the display device 100 according to the present invention, the organic layer 134 that emits white light is formed over the entire area of the substrate 140. However, due to the undercut structures of the first pattern 162 and the second pattern 164, the organic layer 134 is disconnected between adjacent sub-pixels SP1 and SP2. Accordingly, since the organic layer 134 can be formed by a single process, the process can be simplified, and since the organic layer 134 is disconnected, lateral leakage current to adjacent sub-pixels SP1 and SP2 can be prevented.

[0117] In particular, in the present invention, the first pattern 162 is made of a material having orthogonality, and the second pattern 164 is made of a photoresist, such that when the first pattern 162 and the second pattern 164 having the undercut structures are formed, no physical damage is applied to other layers, and thus defects due to damage to the thin film layer can be prevented.

[0118] Hereinafter, a method of manufacturing the display device 100 according to the present invention will be described in detail.

[0119] Figures 6A to 6I are views showing a method of manufacturing the display device 100 according to the present invention.

[0120] First, as Figure 6A shown, a buffer layer 142 is formed over the entire substrate 140 including a plurality of sub-pixels SP1 and SP2.

[0121] The substrate 140 may be made of a hard material such as glass or a plastic material. For example, the plastic material may include polyimide, polymethyl methacrylate, polyethylene terephthalate, polyethersulfone, and polycarbonate.

[0122] The buffer layer 142 may be formed of a single layer of SiNx or SiOx or a multi-layer thereof.

[0123] Thereafter, a polycrystalline semiconductor material such as polysilicon or an oxide semiconductor material such as etched IGZO (indium gallium zinc oxide), IZO (indium zinc oxide), IGTO (indium gallium tin oxide), and IGO (indium gallium oxide) is deposited and etched to form a semiconductor layer 112 in each of the first to third sub-pixels SP1 and SP2 over the buffer layer 142. In addition, impurities are doped into both sides of the semiconductor layer 112 to form channel regions 112a, source regions 112b, and drain regions 112c.

[0124] Subsequently, a gate insulating layer 144 is formed by depositing an inorganic material such as SiOx or SiNx, and then a metal such as molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu) is deposited by a sputtering method and etched by a wet etching method to form a gate electrode 114. Thereafter, an organic material such as a photoacrylic material or an inorganic material such as SiNx or SiOx is deposited on the gate electrode 114 to form an interlayer insulating layer 146, and then the interlayer insulating layer 146 above the source region 112b and the drain region 112c of the semiconductor layer 112 is dry-etched to form contact holes therein.

[0125] Subsequently, a metal such as Cr, Mo, Ta, Cu, Ti, Al, or an Al alloy is deposited by a sputtering method and etched to form a source electrode 115 and a drain electrode 116, and the source electrode 115 and the drain electrode 116 are in ohmic contact with the source region 112b and the drain region 112c of the semiconductor layer 112 through contact holes in each of the first to third sub-pixels SP1, SP2, and SP3, respectively.

[0126] After that, as Figure 6B shown, a planarization layer 148 is formed by depositing an organic material (such as photoacrylic) on the source electrode 115 and the drain electrode 116, and then the planarization layer 148 on the drain electrode 116 is dry-etched to form contact holes.

[0127] Subsequently, a metal or a metal oxide is deposited on the planarization layer 148 by a sputtering method and then etched by a wet etching method to form a first electrode 132, and the first electrode 132 is electrically connected to the drain electrode 116 through contact holes in each of the sub-pixels SP1 and SP2. Thereafter, at least one material selected from an inorganic insulating material (such as SiNx or SiOx), an organic material (such as BCB (benzocyclobutene), acrylic resin, epoxy resin, phenolic resin, polyamide resin, and polyimide resin, and a photoresist including a black pigment)) is deposited on the edge regions of the planarization layer 148 and the first electrode 132 and dry-etched to form a bank layer BNK.

[0128] Subsequently, as Figure 6C shown, a material having orthogonality (i.e., a fluorine-containing polymer material containing a large amount of fluorine (F) in a functional group) continuously forms carbon-carbon bonds in a chain structure, and a photoresist is continuously deposited to form an orthogonal material layer 162a and a photoresist layer 164a in the sub-pixels SP1 and SP2.

[0129] After that, when the photoresist layer 164a is exposed and developed using a photomask (not shown), as Figure 6DAs shown, a second pattern 164 is formed on the orthogonal material layer 162a. In this case, the second pattern 164 can be formed to have a width approximately similar to the width of the bank layer BNK.

[0130] Subsequently, the second pattern 164 is used as a mask layer to etch the lower orthogonal material layer 162a, such that the first pattern 162 is formed below the second pattern 164, as Figure 6E shown. At this time, the first pattern 162 is over-etched to each part of the first pattern 162 below the second pattern 164, such that the upper second pattern 164 and the lower first pattern 162 form an undercut shape.

[0131] After that, an organic material is deposited in the entire area of the substrate 140, and then a translucent alloy such as LiF / Al, CsF / Al, Mg:Ag, Ca / Ag, Ca:Ag, LiF / Mg:Ag, LiF / Ca / Ag, LiF / Ca:Ag or a metal such as silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), or chromium (Cr) is deposited, such that the organic layer 134 and the third electrode 135 are formed on the first electrode 132 exposed between the bank layers BNK, and the organic pattern 134a and the conductive pattern 135a are formed on the second pattern 164.

[0132] As Figure 7A shown, the width of the first pattern 162 is smaller than the width of the second pattern 164, such that the first pattern 162 and the second pattern 164 are formed to have an undercut shape with a reverse step difference. At this time, the degree of the reverse step difference between the first pattern 162 and the second pattern 164 (i.e., the depth (l1) of the undercut shape) causes the disconnection of the organic layer 134 and the organic pattern 134a and the disconnection of the third electrode 135 and the conductive pattern 135a.

[0133] As described above, in the present invention, since the organic layer 134 is disconnected between adjacent sub-pixels SP1 and SP2, it is possible to prevent the lateral leakage current from flowing through the organic layer 134 to reach the adjacent sub-pixels SP1 and SP2, thereby preventing defects caused by the leakage current.

[0134] In addition, in the present invention, the organic layer 134 is formed at a desired position (i.e., on the first electrode 132 of the sub-pixels SP1 and SP2) by using the first pattern 162 having orthogonality. Since the orthogonal material has properties independent of other adjacent layers, when the first pattern 162 is formed, no chemical damage occurs between the first pattern 162 and the lower layer (which is the planarization layer 148 or the first electrode (132)), and when the first pattern 162 is etched, no damage is caused to the planarization layer 148 or the first electrode 132.

[0135] Subsequently, heat is applied to the entire area of the substrate 140 to perform heat treatment. The undercut shapes of the first pattern 162 and the second pattern 164 can be changed through heat treatment. As Figure 6G and Figure 7B shown, due to the reduction in the width difference between the first pattern 162 and the second pattern 164, the depth (l2) of the undercut shape is reduced through heat treatment (l2 < l1), and thus the edge region of the second pattern 164 changes from an acute angle to a curved shape.

[0136] After that, a metal or metal oxide is deposited over the entire area of the substrate 140 to form the second electrode 136. At this time, since the undercut depth of the undercut shapes of the first pattern 162 and the second pattern 164 is small, and the edge region of the second pattern 164 is formed into a curved shape, the second electrode 136 is formed to extend from the upper surface of the conductive pattern 135a on the second pattern 164 to the upper surface of the third electrode 135 along the side surfaces of the first pattern 162 and the second pattern 164. That is, the second electrode 136 is integrally formed without discontinuity in the entire area of the sub-pixels SP1 and SP2.

[0137] After that, as Figure 6I shown, an inorganic material is deposited over the entire area of the sub-pixels SP1 and SP3 to form the first encapsulation layer 182, and an organic material is deposited on the first encapsulation layer 182 to form the second encapsulation layer 184. After that, an inorganic material is deposited on the second encapsulation layer 184 to form the third encapsulation layer 186, thereby forming the encapsulation layer 180 to seal the display device 100.

[0138] Subsequently, a color photoresist or the like is deposited on the encapsulation layer 180 and patterned to form color filter layers CF1 and CF2 in the sub-pixels SP1 and SP2. At this time, the color filter layers CF1 and CF2 can be red filter layers, green filter layers, and blue filter layers. In addition, the color filter layers CF1 and CF2 can be white filter layers. The W color filter layer can form a separate layer that directly transmits white light, or can directly transmit white light without a separate layer.

[0139] After that, a transparent protection film 190 (such as a PS (polystyrene) film, a PE (polyethylene) film, a PEN (polyethylene naphthalate) film, or a PI (polyimide) film) is attached to the color filter layers CF1 and CF2 using an adhesive (not shown in the figure) (such as OCR (optical clear resin) or OCA (optical clear adhesive)) to manufacture the display device 100.

[0140] As described above, in the display device 100 according to the present invention, the first pattern 162 having orthogonality and the second pattern 164 made of photoresist are formed in an undercut shape, so that a single organic layer 134 can be formed for each of the sub-pixels SP1 and SP2 by a single deposition process, thereby simplifying the manufacturing process.

[0141] At this time, since the first pattern 162 for patterning the organic layer 134 is made of a material having orthogonality, there is no physical damage to other layers when forming the first pattern 162 and the second pattern 164 having an undercut structure. Therefore, defects due to damage to the thin film layer can be prevented.

[0142] Figure 8 FIG. is a cross-sectional view showing the structure of a display device 200 according to a second embodiment of the present invention. At this time, the description of the same structure as that of Figure 5 the first embodiment will be omitted or simplified, and only the different structures will be described in detail.

[0143] As Figure 8 shown, in the display device 200 according to the second embodiment of the present invention, thin film transistors T and light emitting devices D are provided in each of the sub-pixels SP1 and SP2.

[0144] The thin film transistor T includes a semiconductor layer 212 provided on the buffer layer 242, a gate electrode 214 provided on the gate insulating layer 244, a source electrode 215 and a drain electrode 216 provided on the interlayer insulating layer 246.

[0145] The light emitting device D is provided in each of the sub-pixels SP1 and SP2 divided by the bank layer BNK. The light emitting device D includes a first electrode 232, an organic layer 234, a third electrode 235, a fourth electrode 236, and a second electrode 237. At this time, the first electrode 232 may be an anode electrode, and the second to fourth electrodes 235, 236, and 237 may be cathode electrodes.

[0146] The first electrode 232 is provided in each of the sub-pixels SP1 and SP2. The first electrode 232 may be formed of at least one of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof, and may also be formed of a transparent metal oxide layer such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0147] The third electrode 235 and the fourth electrode 236 as cathode electrodes are formed in the entire area of the display device 200, but are disconnected at the boundaries of the sub-pixels SP1 and SP2 by the first pattern 262 and the second pattern 264 in an undercut shape.

[0148] The first pattern 262 is made of a material having orthogonality, that is, the fluoropolymer material contains a large amount of fluorine (F) in the functional group, and at the same time, carbon-carbon bonds are continuously formed in a chain structure, and the second pattern 264 is made of a photoresist. At this time, the width of the first pattern 262 is formed to be smaller than the width of the second pattern 264, so that the first pattern 262 and the second pattern 264 are formed in an undercut shape with a reverse step.

[0149] The third electrode 235 can be made of a translucent alloy such as LiF / Al, CsF / Al, Mg:Ag, Ca / Ag, Ca:Ag, LiF / Mg:Ag, LiF / Ca / Ag, LiF / Ca:Ag or a metal such as silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W) or chromium (Cr). The second electrode 236 can be made of a transparent metal oxide that transmits light, such as ITO or IZO.

[0150] In this embodiment, the reason for forming the fourth electrode 236 made of a transparent metal oxide on the third electrode 235 is to prevent the third electrode 235 from being oxidized. After the organic layer 234 is formed, the third electrode 235 is formed by sputtering over the entire area of the substrate 240. At this time, since the third electrode 235 is exposed to the outside, the third electrode 235 is oxidized by combining with oxygen in the air.

[0151] The oxidation of the third electrode 235 causes impurities such as oxygen to penetrate into the adjacent organic layer 234, and the organic layer 234 deteriorates due to the penetration of the impurities, resulting in a defective display device 200. The fourth electrode 236 made of a metal oxide is formed on the third electrode 235 so that the third electrode 235 is not exposed to the outside, thereby preventing the oxidation of the third electrode 235.

[0152] The second electrode 237 is formed in the entire area of the display device 200. That is, the second electrode 237 is formed to extend from the upper surface of the fourth electrode 236 of the sub-pixels SP1 and SP2 to the side surfaces of the first pattern 262 and the second pattern 264, the organic pattern 234a provided on the upper surface of the second pattern 264, the side surfaces of the first conductive pattern 235a and the second conductive pattern 236a, and the upper surface of the second conductive pattern 236a.

[0153] The first pattern 262 and the second pattern 264 have an undercut shape such that the third electrode 235 and the first conductive pattern 235a are disconnected from each other, and the fourth electrode 236 and the second conductive pattern 236a are disconnected from each other. On the other hand, since the second electrode 237 is formed in the entire area of the display device 200, the cathode electrodes formed in each of the sub-pixels SP1 and SP2 are electrically connected to each other through the second electrode 237.

[0154] The encapsulation layer 280 is formed over the organic light-emitting device D, the color filters CF1 and CF2 are disposed thereon, and the protection member 290 is disposed on the color filter layers CF1 and CF2.

[0155] Although the cathode electrode of the display device 100 of the first embodiment is formed of the third electrode 135 (which is made of an alloy or a metal) and the second electrode 136 (which is made of a metal oxide), the cathode electrode of the display device 200 of the present embodiment is formed of the third electrode 235 (which is made of an alloy or a metal), the fourth electrode 236 (which is made of a metal oxide), and the second electrode 237 (which is made of a metal oxide).

[0156] However, the cathode electrode of the present invention is not limited to this configuration. The cathode electrode of the present invention may be formed only of the second electrode (which is made of a metal oxide). At this time, the second electrode is disposed on the organic layer and may be formed over the entire area of the display device without being disconnected due to the undercut shapes of the first pattern and the second pattern.

[0157] Figure 9 is a cross-sectional schematic view showing the structure of a display device 300 according to a third embodiment of the present invention. At this time, the description of the same structure as that of Figure 5 the first embodiment will be omitted or simplified, and only the different structures will be described in detail.

[0158] As Figure 9 shown, in the display device 300 according to the third embodiment of the present invention, a thin-film transistor T and a light-emitting device D are disposed in each of the sub-pixels SP1 and SP2.

[0159] The thin-film transistor T includes a semiconductor layer 312 disposed on the buffer layer 342, a gate electrode 314 disposed on the gate insulating layer 344, a source electrode 315 and a drain electrode 316 disposed on the interlayer insulating layer 346.

[0160] The light-emitting device D is disposed in each of the sub-pixels SP1 and SP2 partitioned by the bank layer BNK. The light-emitting device D includes a first electrode 332, an organic layer 334, a third electrode 335, and a second electrode 336. At this time, the first electrode 332 may be an anode electrode, and the second electrode 336 and the third electrode 335 may be cathode electrodes.

[0161] The first electrode 332 is disposed in each of the sub-pixels SP1 and SP2. The first electrode 332 may be formed of at least one of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof, and may also be formed of a transparent metal oxide layer such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0162] The bank layer BNK is formed on the planarization layer 348 between adjacent sub-pixels SP1 and SP2. The first pattern 362 is disposed on the bank layer BNK. The first pattern 362 can be made of a material having orthogonality, that is, a fluoropolymer material contains a large amount of fluorine (F) in the functional group while continuously forming carbon-carbon bonds in a chain structure.

[0163] The auxiliary electrode 363 is disposed on the first pattern 362. The auxiliary electrode 363 is formed in a matrix shape over the entire area of the substrate 340, similar to the bank layer BNK. The auxiliary electrode 363 can be made of at least one of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof.

[0164] The second pattern 364 is formed on the auxiliary electrode 363. The second pattern 364 is made of a photoresist. The width of the second pattern 364 is substantially the same as the width of the auxiliary electrode 363, and the width of the first pattern 362 is smaller than the widths of the second pattern 364 and the auxiliary electrode 363, such that the first pattern 362 at the bottom and the auxiliary electrode 363 and the second pattern 364 at the top are formed in an undercut shape with a reverse step.

[0165] The organic layer 334 and the third electrode 335 are formed on the first electrode 332 between the bank layers BNK, and the organic pattern 334a and the conductive pattern 335a are formed on the second pattern 364. The organic layer 334, the organic pattern 334a, the third electrode 335, and the conductive pattern 335a are integrally formed over the entire area of the substrate 340, but are disconnected from each other at the boundary of the sub-pixels SP1 and SP2 by the undercut shape of the first pattern 362, the auxiliary electrode 363, and the second pattern 364.

[0166] The third electrode 335 can be made of a metal such as silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), or chromium (Cr). The second electrode 336 can be made of a light-transmitting transparent metal oxide such as ITO or IZO.

[0167] In addition, although not shown in the figure, a metal oxide layer can be formed on the third electrode 335 to prevent oxidation of the third electrode 335 during the process.

[0168] The second electrode 336 is formed over the entire area of the display device 300. That is, the second electrode 336 is formed to continuously extend from the upper surface of the third electrode 335 of the sub-pixels SP1 and SP2 to the side surfaces of the first pattern 362, the auxiliary electrode 363, and the second pattern 364, the side surfaces of the organic pattern 334a and the conductive pattern 335a above the upper part of the second pattern 364, and the upper surface of the conductive pattern 335a.

[0169] Due to the undercut shapes of the first pattern 362, the auxiliary electrode 363, and the second pattern 364, the organic layer 334 and the organic pattern 334a are disconnected from each other, and the third electrode 335 and the conductive pattern 335a are disconnected from each other. On the other hand, since the second electrode 336 is formed over the entire area of the display device 300, the cathode electrodes formed in each of the sub-pixels SP1 and SP2 are electrically connected to each other through the second electrode 336.

[0170] Since the auxiliary electrode 363 made of a conductive metal having good conductivity is arranged in a matrix shape between the sub-pixels SP1 and SP2 over the entire area of the display device 300, the auxiliary electrode 363 is electrically connected to the second electrode 336 having poor conductivity in the sub-pixels SP1 and SP2, so that a signal applied from the outside is applied to the second electrode 336 through the auxiliary electrode 363 without signal delay. Therefore, it is possible to prevent defects caused by signal delay to the cathode electrode.

[0171] Although not shown in the drawings, in the display device 300 of the present embodiment, the second electrode 336 may be directly formed on the organic layer 334 without the third electrode 335. In this case, the second electrode 336 is electrically connected to the auxiliary electrode 363 to supply a signal to the entire area of the display device 300, thereby preventing signal delay due to the high resistance of the metal oxide of the second electrode 336.

[0172] Refer again to Figure 9 , the encapsulation layer 380 is formed on the organic light-emitting device D, the color filters CF1 and CF2 are formed on the encapsulation layer 380, and the protection member 390 is disposed on the color filter layers CF1 and CF2.

[0173] As described above, in the display device 300 of the present embodiment, by arranging the auxiliary electrode 363 between the first pattern 362 and the second pattern 364 on the bank layer BNK to electrically connect the second electrode 336 to the auxiliary electrode 363, it is possible to prevent defects caused by signal delay to the cathode electrode.

[0174] Figures 11A to 11E is a view showing a method for manufacturing a display device 300 according to a third embodiment of the present invention.

[0175] As Figure 11A shown, first, a thin-film transistor T is formed in each of the sub-pixels SP1 and SP2 above the substrate 340, and then a planarization layer 348 is formed over the entire area of the substrate 340.

[0176] Thereafter, the planarization layer 348 on the drain electrode 316 is dry-etched to form contact holes, and then a metal or metal oxide is deposited on the planarization layer 348 by a sputtering method and etched by a wet-etching method to form a first electrode 332, and the first electrode 332 is electrically connected to the drain electrode 316 through the contact holes in each of the sub-pixels SP1 and SP2.

[0177] Subsequently, a bank layer BNK is formed on the edge regions of the planarization layer 348 and the first electrode 332, and then a material layer 362a, a metal layer 363a made of metal, and a photoresist layer 364a are formed. The material layer 362a is made of a fluorine-containing polymer material containing a large amount of fluorine (F) in the functional group and continuously forms carbon-carbon bonds in a chain structure.

[0178] Thereafter, as Figure 11B shown, the photoresist layer 364a is exposed and developed using a photomask (not shown in the figure) to form a second pattern 364 on the metal layer 363a above the bank layer BNK. At this time, the second pattern 364 can be formed to have a width approximately similar to the width of the bank layer BNK.

[0179] Thereafter, as Figure 11C shown, the metal layer 363a is etched using the second pattern 364 as a mask layer to form an auxiliary electrode 363. At this time, the auxiliary electrode 363 is formed to have substantially the same width as the second pattern 364.

[0180] Subsequently, as Figure 11D shown, the orthogonal material layer 362a is etched using the second pattern 364 as a mask layer to form a first pattern 362 under the auxiliary electrode 363. At this time, the first pattern 362 is over-etched such that the portion of the first pattern 362 under the auxiliary electrode 363 is etched, and the auxiliary electrode 363, the second pattern 364, and the first pattern 362 form an undercut shape.

[0181] Thereafter, an organic layer 334 and a third electrode 335 are formed on the first electrode exposed between the bank layers BNK continuously over the entire area of the substrate 340 with an organic material and a metal oxide such as IZO or ITO, and an organic pattern 334a and a conductive pattern 335a are formed on the second pattern 364.

[0182] At this time, the organic layer 334 and the third electrode 335 are disconnected from the organic pattern 334a and the conductive pattern 335a respectively through the undercut shapes of the first pattern 362, the auxiliary electrode 363, and the second pattern z64. That is, the organic light-emitting material and the metal oxide are deposited over the entire area of the substrate 340, but the organic layer and the conductive layer are disconnected through the undercut shapes of the first pattern 362, the auxiliary electrode 363, and the second pattern 364.

[0183] After that, as Figure 11E shown, heat is applied to the entire area of the substrate 340 to perform heat treatment. The undercut shapes of the first pattern 362, the auxiliary electrode 363, and the second pattern 364 can be changed by the heat treatment. That is, due to the reduction in the width difference between the first pattern 362 and the second pattern 364, the depth of the undercut shape is reduced by the heat treatment, and thus the edge regions of the auxiliary electrode 363 and the second pattern 364 are changed from acute angles to curved shapes.

[0184] After that, a metal or a metal oxide is deposited over the entire area of the substrate 340 to form the second electrode 336. At this time, since the undercut depth of the undercut shapes of the first pattern 362 and the second pattern 364 is small, and the edge region of the second pattern 364 is formed in a curved shape, the second electrode 336 is formed to extend from the upper surface of the conductive pattern 335a on the second pattern 364 to the upper surface of the third electrode 335 along the side surfaces of the first pattern 362, the auxiliary electrode 363, and the second pattern 364. That is, the second electrode 336 is integrally formed without being disconnected in the entire area of the sub-pixel SP1 to be electrically connected to the side surface and the bottom surface of the auxiliary electrode 363.

[0185] After that, an inorganic material is deposited over the entire areas of the sub-pixels SP1 and SP3 to form the first encapsulation layer 382, and an organic material is deposited on the first encapsulation layer 382 to form the second encapsulation layer 384. After that, an inorganic material is deposited on the second encapsulation layer 384 to form the third encapsulation layer 386, thereby forming the encapsulation layer 380 to seal the display device 300.

[0186] Subsequently, a color photoresist or the like is deposited on the encapsulation layer 380 and patterned to form color filter layers CF1 and CF2 in the sub-pixels SP1 and SP2, and then a transparent protective film 382 is attached to the color filter layers CF1 and CF2 by an adhesive (not shown in the figure).

[0187] The above description and the drawings only illustrate the technical spirit of the present disclosure, and those of ordinary skill in the art to which the present disclosure pertains can combine configurations and may make various modifications or variations, such as separation, replacement, and change, without departing from the basic features of the present disclosure. Therefore, the embodiments disclosed in the present disclosure are not intended to limit the technical spirit of the present disclosure, but for explanation, and the scope of the technical spirit of the present disclosure is not limited by these embodiments.

Claims

1. A display device, comprising: a substrate including a plurality of sub-pixels; a bank layer surrounding the plurality of sub-pixels; a first pattern and a second pattern disposed on the bank layer; and a light-emitting device, the light-emitting device including: a first electrode disposed in the sub-pixel between the bank layers, an organic layer on the first electrode, and a second electrode on the organic layer, and wherein the second electrode extends from above the organic layer to the second pattern.

2. The display device according to claim 1, further comprising an auxiliary electrode disposed between the first pattern and the second pattern and electrically connected to the second electrode.

3. The display device according to claim 1, further comprising: a encapsulation layer above the light-emitting device; wherein the encapsulation layer is formed of a first encapsulation layer, a second encapsulation layer, and a third encapsulation layer, the first encapsulation layer and the third encapsulation layer are made of an inorganic material, and the second encapsulation layer is made of an organic insulating material.

4. The display device according to claim 3, wherein, Each of the sub-pixels includes a color filter layer above the encapsulation layer, and an interface of the color filter layers of adjacent sub-pixels overlaps with the first pattern or the second pattern.

5. The display device according to claim 1, wherein, The bank layer includes a black pigment.

6. The display device according to claim 1, further comprising: a transistor disposed in each sub-pixel, the transistor including a semiconductor pattern; wherein the semiconductor pattern is made of an oxide semiconductor.

7. The display device according to claim 6, wherein, A planarization layer is formed between the first electrode and the transistor.

8. The display device according to claim 1, wherein, The first pattern and the second pattern are formed in a matrix shape.

9. The display device according to claim 1, wherein, The width of the first pattern is smaller than the width of the second pattern to form an undercut shape.

10. The display device according to claim 1, further comprising a third electrode on the organic layer between the second electrode and the organic layer.

11. The display device according to claim 10, wherein, The second electrode extends from the third electrode to the second pattern.

12. The display device according to claim 10, wherein, The second electrode is made of a metal oxide, and the third electrode is made of a metal.

13. The display device according to claim 10, wherein, The second electrode and the third electrode form a cathode electrode.

14. The display device according to claim 10, further comprising: an organic pattern on the second pattern; and a conductive pattern on the organic pattern.

15. The display device according to claim 14, wherein: the width of the first pattern is smaller than the width of the second pattern to form an undercut shape, the organic pattern is disconnected from the organic layer through the undercut shape of the first pattern and the second pattern, and the conductive pattern is disconnected from the third electrode through the undercut shape of the first pattern and the second pattern.

16. The display device according to claim 1, wherein, The second electrode is integrally formed in the entire sub-pixel.

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