Display device

Abstract

An embodiment discloses a display device including: a plurality of first electrodes and a contact electrode disposed on a substrate; a first bank and a second bank disposed on the substrate; a first light emitting element disposed on the first bank; a second light emitting element disposed on the second bank; a first optical layer and a first member disposed between the first light emitting element and the second light emitting element; and a second electrode disposed on the first light emitting element and the second light emitting element. The second electrode extends outwardly from the first optical layer disposed between the first light emitting element and the second light emitting element and is electrically connected to the contact electrode.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0160404, filed on November 20, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates to a display device, and more particularly to a display device including a light emitting diode. Background Art

[0004] The electroluminescent display device is used to display images using self-luminous elements, and can be implemented in a thin and diverse form because it does not require a separate light source such as a backlight unit.

[0005] Electroluminescent display devices include organic light-emitting display devices in which organic light-emitting diodes (OLEDs) (hereinafter referred to as "OLEDs") are arranged, and inorganic light-emitting display devices (hereinafter referred to as "LED display devices") in which inorganic light-emitting diodes (LEDs) (hereinafter referred to as "LEDs") are arranged.

[0006] As an example of an inorganic light-emitting display device, a micro LED display device having micro LEDs arranged in pixels is emerging as a next-generation display device. Micro LEDs may be inorganic light-emitting diodes having a size of 100 μm or less. Micro LEDs may be manufactured by a separate semiconductor process, and they may be transferred to a pixel position on a substrate of a display panel of a display device and arranged in corresponding sub-pixels for each color. Summary of the invention

[0007] The LED in the light emitting diode display device is a point light source, so it can emit light in any direction. When the light emitting diode display device is implemented as a unidirectional display device, the light emitted in any direction other than the display direction will be extinguished, resulting in low light emission efficiency.

[0008] The present disclosure aims to provide a display device with improved luminous efficiency to solve the above problems. However, the problems of the present disclosure are not limited to those mentioned above, and other technical problems can be derived from the following embodiments.

[0009] According to one embodiment of the present disclosure, a display device includes: a plurality of first electrodes and contact electrodes arranged on a substrate; a first embankment and a second embankment arranged on the substrate; a first light-emitting element arranged on the first embankment; a second light-emitting element arranged on the second embankment; a first optical layer and a first component arranged between the first light-emitting element and the second light-emitting element; and a second electrode arranged on the first light-emitting element and the second light-emitting element, wherein the second electrode extends outward from the first optical layer arranged between the first light-emitting element and the second light-emitting element and is electrically connected to the contact electrode.

[0010] Specific details of other embodiments are set forth in the detailed description and accompanying drawings.

[0011] The display device according to the present disclosure can improve the light emission efficiency by providing a high reflective metal layer between a plurality of light emitting elements. In addition, the power consumption of the display device can be reduced as the light emission efficiency increases.

[0012] The effects of the present disclosure are not limited to the above-mentioned effects, and other effects that are not mentioned will be clearly understood by those skilled in the art from the following description and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The above and other objects, features and advantages of the present disclosure will become more apparent to those skilled in the art by describing in detail exemplary embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0014] Figure 1 is a diagram illustrating a display device according to one embodiment of the present disclosure;

[0015] Figure 2 yes Figure 1 An enlarged view of area "A" in FIG.

[0016] Figure 3 is a diagram illustrating a partial area of ​​a pixel of a display device according to an embodiment of the present disclosure;

[0017] Figure 4 is along Figure 3 A cross-sectional view taken along line II' in FIG.

[0018] Figure 5 is along Figure 3 A cross-sectional view taken along line II-II';

[0019] Figure 6 yes Figure 5 An enlarged view of area "B" in FIG.

[0020] FIG. 7A to FIG. 7Gis a diagram illustrating a method of manufacturing a display device according to one embodiment of the present disclosure;

[0021] Figure 8 yes Figure 5 Another embodiment of; and

[0022] Fig. 9 yes Figure 5 Yet another implementation method. DETAILED DESCRIPTION

[0023] The advantages and features of the present disclosure and the methods for achieving the advantages and features will become apparent from the embodiments described below in conjunction with the accompanying drawings. However, the present disclosure is not limited to the following embodiments, but can be implemented in various different forms; on the contrary, the present embodiments are provided to make the disclosure of the present disclosure complete and enable those skilled in the art to fully understand the scope of the present disclosure, and the present disclosure is limited only within the scope of the appended claims.

[0024] The shapes, sizes, ratios, angles, quantities, etc. of the elements shown in the drawings for illustrating the embodiments of the present disclosure are illustrative only and are not intended to be limiting. In addition, when describing the present disclosure, detailed descriptions of well-known technologies may be omitted so as not to obscure the essence of the present disclosure.

[0025] Terms such as "including," "having," and "comprising" as used herein are generally intended to allow for the addition of other components unless these terms are used with the term "only." Reference to components of a singular noun includes the plural of that noun unless specifically stated otherwise.

[0026] When interpreting the components, even if there is no explicit description, it is interpreted as including the error range.

[0027] When describing a positional relationship, for example, if the positional relationship of two components is described as "on," "above," "below," and "next to," unless "immediately" or "directly" is used, one or more other components may be set between the two components.

[0028] When an element or layer is referred to as being on another element or layer, this includes any intervening layers or other elements directly on top of or between the other elements.

[0029] In addition, first, second, etc. are used to describe various components, but these components are not limited by these terms. These terms are only used to distinguish one component from another component. Therefore, within the technical spirit of the present disclosure, the first component mentioned below may be the second component.

[0030] Like reference numerals may refer to like parts throughout the application.

[0031] The size and thickness of each configuration shown in the drawings are shown only for the purpose of explanation and are not necessarily limited to the size and thickness of the configuration shown herein.

[0032] Each of the features of the various embodiments described herein may be combined or combined with each other in whole or in part and may be technically interlocked and operated in various ways, and each of these embodiments may be performed independently or in combination with each other.

[0033] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0034] A display device according to an embodiment of the present disclosure includes: a display panel having a screen or a display area on which an image is displayed; and a pixel driving circuit driving pixels on the display panel. The display area includes a pixel area where pixels are arranged. The pixel area includes a plurality of light-emitting areas. A light-emitting element is arranged in each light-emitting area. The pixel driving circuit may be built into the display panel.

[0035] Figure 1 is a diagram illustrating a display device according to one embodiment of the present disclosure. Figure 2 yes Figure 1 Magnified view of area "A" in FIG. Figure 3 is a diagram illustrating a partial area of ​​a pixel of a display device according to an embodiment of the present disclosure.

[0036] Reference Figure 1 and Figure 2 The display device 10 according to an embodiment of the present disclosure includes a display panel on which an input image is visually reproduced. The display panel may include a display area 12 that displays an image and a non-display area 14 that does not display an image. In the non-display area 14, various wirings and driving circuits may be installed, and a pad portion PAD for connecting an integrated circuit, a printed circuit, etc. may be provided.

[0037] The plurality of light emitting elements 100 disposed in the display region 12 to form the pixel PXL may be micro inorganic light emitting elements. The inorganic light emitting elements may be grown on a silicon wafer and then attached to the display panel through a transfer process.

[0038] The transfer process of the light emitting element 100 may be performed for each pre-divided region. Figure 1 The display area 12 is illustrated as being divided into twelve transfer areas 16, but the size of the transfer area or the number of divisions of the transfer area is not limited thereto. The transfer process may be performed sequentially or simultaneously in the first to twelfth transfer areas 16. The blue light emitting element 100, the green light emitting element 100, and the red light emitting element 100 may be sequentially transferred to the transfer area 16.

[0039] In the non-display area 14, a data driving circuit or a gate driving circuit may be provided, and wiring for providing a control signal for controlling the driving circuit may be provided. Here, the control signal may include various timing signals, and the control signal may be received through the pad portion PAD, and the various timing signals may include a clock signal, an input data enable signal, and a synchronization signal.

[0040] The pixel PXL can be driven by a pixel driving circuit. The pixel driving circuit can receive a driving voltage, an image signal (digital signal), a synchronization signal synchronized with the image signal, etc., and can output an anode voltage and a cathode voltage of the light-emitting element 100 to drive a plurality of pixels. The driving voltage can be a high potential voltage EVDD. The cathode voltage can be a low potential voltage EVSS commonly applied to the pixel. The anode voltage can be a voltage corresponding to the pixel data value of the image signal. The pixel driving circuit can be arranged in the non-display area 14, or it can be arranged below the display area 12.

[0041] Each pixel PXL may include a plurality of sub-pixels having different colors. For example, the plurality of pixels may include a red sub-pixel provided with a light emitting element 100 emitting light of a red wavelength, a green sub-pixel provided with a light emitting element 100 emitting light of a green wavelength, and a blue sub-pixel provided with a light emitting element 100 emitting light of a blue wavelength. The plurality of pixels may further include a white sub-pixel.

[0042] Reference Figure 2 and Figure 3 , a plurality of pixels PXL may be arranged continuously along the first direction (X-axis direction) and the second direction (Y-axis direction). A plurality of sub-pixels of the same color may be arranged in the pixel of the display area 12. For example, each of the plurality of sub-pixels may include: a first red sub-pixel in which the 1-1 red light emitting element 100R emitting light of a red wavelength is arranged; a second red sub-pixel in which the 1-2 red light emitting element 100R' emitting light of a red wavelength is arranged; a first green sub-pixel in which the 2-1 green light emitting element 100G emitting light of a green wavelength is arranged; a second green sub-pixel in which the 2-2 green light emitting element 100G' emitting light of a green wavelength is arranged; a first blue sub-pixel in which the 3-1 blue light emitting element 100B emitting light of a blue wavelength is arranged; and a second blue sub-pixel in which the 3-2 blue light emitting element 100B' emitting light of a blue wavelength is arranged. The 1-1 red light emitting element 100R, the 2-1 green light emitting element 100G, and the 3-1 blue light emitting element 100B may be considered as main light emitting elements.

[0043] The 1-2nd red light emitting element 100R', the 2-2nd green light emitting element 100G', and the 3-2nd blue light emitting element 100B' may be regarded as sub-light emitting elements.

[0044] One sub-pixel may include at least one or more light emitting elements, and when one light emitting element becomes defective, the brightness of another light emitting element may be increased to adjust the brightness of the sub-pixel. However, the embodiment is not necessarily limited thereto, and one sub-pixel may include only one light emitting element.

[0045] A plurality of first electrodes 102 may be respectively disposed on the lower portion of the light emitting element 100, and the plurality of first electrodes 102 may be selectively connected to a plurality of signal wirings TL1 to TL6 through the extensions 102a. A high potential voltage may be applied to the pixel driving circuit through the signal wirings TL1 to TL6. During the electrode patterning process, the signal wirings TL1 to TL6 and the first electrodes 102 may be formed as an integrated electrode pattern.

[0046] For example, the first signal wiring TL1 may be connected to the anode electrode of the first red sub-pixel, and the second signal wiring TL2 may be connected to the anode electrode of the second red sub-pixel. The third signal wiring TL3 may be connected to the anode electrode of the first green sub-pixel, and the fourth signal wiring TL4 may be connected to the anode electrode of the second green sub-pixel. The fifth signal wiring TL5 may be connected to the anode electrode of the first blue sub-pixel, and the sixth signal wiring TL6 may be connected to the anode electrode of the second blue sub-pixel. When one sub-pixel includes only one light-emitting element, the number of signal wirings TL may be reduced by half.

[0047] The second electrode 104 may be a cathode electrode that is provided one for each row and applies a cathode voltage to the light emitting elements 100 that are continuously arranged in the first direction (X-axis direction). A plurality of second electrodes 104 may be spaced apart from each other in the second direction (Y-axis direction). A plurality of second electrodes 104 may be connected to the cathode voltage through a contact electrode 106. Each of the plurality of second electrodes 104 may be electrically connected to the contact electrode 106. However, the embodiment is not necessarily limited thereto, and the second electrode 104 may be configured as one electrode layer without being divided into a plurality of electrodes, and the second electrode 104 may be used as a common electrode.

[0048] Figure 4 is along Figure 3 A cross-sectional view taken along line II' in FIG. Figure 5 is along Figure 3 A cross-sectional view taken along line II-II'. Figure 6 yes Figure 5 Magnified view of area "B" in FIG.

[0049] Now refer to Figures 4 to 6, a display device according to an embodiment of the present disclosure may include at least one of the following: a substrate 20, a plurality of first electrodes 102 and contact electrodes 106 disposed on the substrate 20, a plurality of light emitting elements 100 disposed on the plurality of first electrodes 102, a first optical layer 136 disposed between the plurality of light emitting elements 100, a first component 122 disposed between the plurality of light emitting elements 100, and a metal layer 124 surrounding the first component 122. In an embodiment, the first component 122 may be referred to as different other terms. For example, the first component 122 may be referred to as a mirror bank, a reflection bank, a mirror unit, an optical control unit, or an optical control element. However, the embodiment is not limited to these terms.

[0050] The substrate 20 may be made of a flexible plastic. For example, the substrate 20 may be made of a single-layer substrate or a multi-layer substrate of a material selected from, but not limited to, polyimide, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyether sulfone, polyarylate, polysulfone, and cyclic olefin copolymer. For example, the substrate 20 may be a ceramic substrate or a glass substrate.

[0051] The pixel driving circuit 200 may be provided in the display region 12 on the substrate 20. The pixel driving circuit 200 may include a plurality of thin film transistors using an amorphous silicon semiconductor, a polysilicon semiconductor, or an oxide semiconductor.

[0052] The pixel driving circuit 200 may include at least one driving thin film transistor, at least one switching thin film transistor, and at least one storage capacitor. When the pixel driving circuit 200 includes a plurality of thin film transistors, it may be formed on the substrate 20 by a thin film transistor (TFT) manufacturing process. According to an embodiment, the pixel driving circuit 200 may be a collective term for a plurality of thin film transistors electrically connected to the light emitting element 100.

[0053] The pixel driving circuit 200 may be a driver manufactured using a metal oxide semiconductor field effect transistor (MOSFET) manufacturing process on a single crystal semiconductor substrate 20. The driver may include a plurality of pixel driving circuits for driving a plurality of sub-pixels. When the pixel driving circuit 200 is implemented as a driver, an adhesive layer may be provided on the substrate 20, and then the driver may be mounted on the adhesive layer by a transfer process.

[0054] A buffer layer 202 covering the pixel driving circuit 200 may be disposed on the substrate 20. The buffer layer 202 may be made of an organic insulating material, such as photosensitive photoacrylic or photosensitive polyimide, but is not limited thereto.

[0055] An insulating layer 204 may be disposed on the buffer layer 202. The insulating layer 204 may be made of an organic insulating material, for example, photosensitive photoacrylic or photosensitive polyimide, but is not limited thereto.

[0056] Connection wirings RT1 and RT2 may be provided on the buffer layer 202. The connection wirings RT1 and RT2 may be connected as corresponding signal wirings TL1 to TL6, or may be connected to the signal wirings TL1 to TL6. The connection wirings RT1 and RT2 may include a plurality of wiring patterns provided in different layers with one or more insulating layers interposed therebetween. The wiring patterns provided in different layers may be electrically connected through contact holes penetrating the insulating layers.

[0057] At least a portion of the first connection wiring RT1 may be disposed on the buffer layer 202 , and at least another portion of the first connection wiring RT1 may be connected to the pixel driving circuit 200 by penetrating the buffer layer 202 .

[0058] At least one of the contact electrode 106 , the plurality of bank patterns 112 , and the passivation layer 120 may be disposed on the insulating layer 204 .

[0059] At least a portion of the contact electrode 106 may be disposed on the insulating layer 204 , and at least another portion of the contact electrode 106 may be electrically connected to the first connection wiring RT1 by penetrating the insulating layer 204 .

[0060] The contact electrode 106 and the signal wirings TL1 to TL6 may be disposed on the same plane. At least a portion of the signal wirings TL1 to TL6 may be disposed on the insulating layer 204 , and at least another portion of the signal wirings TL1 to TL6 may be electrically connected to the second connection wiring RT2 by penetrating the insulating layer 204 .

[0061] The bank pattern 112 may be formed of an organic insulating material such as photosensitive photoacrylic or photosensitive polyimide, but is not limited thereto. The bank pattern 112 may guide a position where the light emitting element 100 is to be attached during a transfer process of the light emitting element 100. According to an embodiment, the bank pattern 112 may be omitted.

[0062] A solder pattern 118 may be disposed on the first electrode 102. The solder pattern 118 may be made of indium (In), tin (Sn), or an alloy thereof, but is not limited thereto.

[0063] The passivation layer 120 may be formed to cover the insulating layer 204, the contact electrode 106, the bank pattern 112, and at least a portion of the first electrode 102. The passivation layer 120 may expose the first electrode 102. The light emitting element 100 and the first electrode 102 may be connected through the portion exposed by the passivation layer 120.

[0064] At least one light emitting element 100 may be disposed on the bank pattern 112. In an embodiment, the first electrode 102 may be disposed on the bank pattern 112. The solder pattern 118 may be disposed on the first electrode 102. The light emitting element 100 may be mounted on the solder pattern 118. At least one light emitting element 100 may be disposed on the solder pattern 118.

[0065] In an embodiment, one pixel may include light emitting elements 100 of three colors 100. For example, the light emitting element 100 may include a red light emitting element, a green light emitting element, or a blue light emitting element. One pixel may include a plurality of sub-pixels, and each of the plurality of sub-pixels may include a light emitting element 100 of a different color. According to an embodiment, two light emitting elements may be mounted on each of the plurality of sub-pixels. In this case, one light emitting element may be a 1-1 light emitting element for normal light emission (for example, Figure 3 The 1-1st red light emitting element 100R in the embodiment, and the other light emitting element may be the 1-2nd light emitting element (for example, Figure 3 The 1st-2nd red light emitting element 100R').

[0066] In an embodiment, Figure 4 The light emitting elements 100 shown in FIG. 1 may be light emitting elements that emit the same color. Figure 5 The light emitting element 100 shown in FIG. 1 may be a light emitting element emitting different colors.

[0067] The first component 122 may be disposed between the plurality of light emitting elements 100. For example, Figure 5 As shown in FIG. 1 , the first component 122 may be disposed between the 1-1 red light emitting element 100R and the 2-1 green light emitting element 100G.

[0068] The first component 122 may include an organic film. For example, the first component 122 may be formed of an organic film including an organic material. The organic material may include, for example but not limited to, acrylic, siloxane, poly(methyl methacrylate) (PMMA), benzocyclobutene (BCB), polyimide, epoxy resin, and polyester.

[0069] In an embodiment, the upper surface of the first component 122 may be formed to be equal to or higher than the height of the upper surface of the light emitting element 100. The upper surface of the first component 122 may be formed to be flat or coplanar with the upper surface of the light emitting element 100. The side surface of the first component 122 may be formed to be inclined or have a constant angle. The side surface of the first component 122 may have a tapered shape. In another embodiment, the first component 122 may be formed in various shapes such as a lens shape. Fig. 9 A more specific example of the above is shown in FIG.

[0070] The metal layer 124 may be formed to surround the upper surface and the side of the first component 122. The metal layer 124 may be formed of, for example, but not limited to, titanium (Ti) or aluminum (Al), which is a metal having a high light reflectivity. The metal layer 124 may reflect light emitted from the side of the light emitting element 100, thereby increasing the light extraction efficiency. For example, when the light emitting element 100 emits light, at least a portion of the emitted light may be incident toward the metal layer 124, and the metal layer 124 may reflect the incident light, thereby increasing the light extraction efficiency.

[0071] The first optical layer 136 may cover the plurality of light emitting elements 100 and the plurality of bank patterns 112. Thus, the first optical layer 136 may cover between the plurality of light emitting elements 100 and between the plurality of bank patterns 112. The first optical layer 136 may extend in the first direction X, and may be spaced apart in the second direction Y and separated between pixel rows.

[0072] The first optical layer 136 may include an organic insulating material in which fine metal particles such as titanium dioxide particles are dispersed. Light emitted from the plurality of light emitting elements 100 may be scattered by the fine metal particles dispersed in the first optical layer 136 and emitted to the outside.

[0073] The second electrode 104 may be provided on the plurality of light emitting elements 100. The second electrode 104 may be commonly connected to the plurality of pixels PXL. The second electrode 104 may be a thin electrode through which light passes. The second electrode 104 may be made of a transparent electrode material such as indium tin oxide (ITO), but is not necessarily limited thereto.

[0074] The second electrode 104 may extend over the plurality of light emitting elements 100 and cover a portion of the first optical layer 136 and the metal layer 124 .

[0075] The second electrodes 104 may extend in the first direction (X-axis direction) and may be spaced apart in the second direction (Y-axis direction). In a plane, each of the plurality of second electrodes 104 may overlap the first optical layer 136 and may cover a plane outside the first optical layer 136 .

[0076] The second optical layer 127 may be an organic insulating material disposed on an upper portion of the second electrode 104. The second optical layer 127 may include the same material (e.g., siloxane) as the first optical layer 136. However, the embodiment is not necessarily limited thereto, and the first optical layer 136 and the second optical layer 127 may be formed of the same material or different materials.

[0077] The second optical layer 127 may be provided to cover the upper portion of at least a portion of the second electrode 104. The second optical layer 127 may cover between the light emitting element 100 and the first component 122. That is, the first optical layer 136 and the second optical layer 127 may function as a planarization layer. As a result, since there is no step in the plane on which the black matrix 128 is formed, a pattern of the black matrix 128 on the second electrode 104 and the second optical layer 127 may be easily formed. However, the embodiment is not necessarily limited thereto, and the top surfaces of the second optical layer 127 and the second electrode 104 may have different heights.

[0078] The black matrix 128 may be an organic insulating material to which a black pigment is added. The second electrode 104 may be in contact with the contact electrode 106 below the black matrix 128. Transmission holes 154 for emitting light emitted from the light emitting element 100 to the outside may be formed between patterns of the black matrix 128. The problem of mixing of light emitted from adjacent light emitting elements 100 due to the first optical layer 136 may be improved by the black matrix 128.

[0079] The cover layer 156 may be an organic insulating material covering the black matrix 128 and the second electrode 104. Figures 6 to 9 In the figure, the structure of the cover layer 156 is omitted.

[0080] Reference Figure 6 , the extension portion 102 a of the first electrode 102 may extend to one side 150 of the bank pattern 112 and be disposed on the insulating layer 204 , and may be electrically connected to the connection wiring RT2 .

[0081] In an embodiment, at least one of the first electrode 102, the extension 102a, the signal wiring TL and / or the connection wirings RT1 and RT2 may include a single layer or multiple layers of metal selected from titanium (Ti), molybdenum (Mo) and aluminum (Al). The first electrode 102, the extension 102a, the signal wiring TL and / or the connection wirings RT1 and RT2 may be formed into a multilayer structure including a first layer ML1, a second layer ML2, a third layer ML3 and a fourth layer ML4.

[0082] For example, the first layer ML1 and the third layer ML3 may include titanium (Ti) or molybdenum (Mo). The second layer ML2 may include aluminum (Al). The fourth layer ML4 may include a transparent conductive oxide layer such as indium tin oxide (ITO) or indium zinc oxide (IZO) having good adhesion, corrosion resistance, and acid resistance to the solder pattern 118.

[0083] The first layer ML1 , the second layer ML2 , the third layer ML3 , and the fourth layer ML4 may be sequentially deposited and then patterned by performing a photolithography process and an etching process.

[0084] The passivation layer 120 may include an open hole 120 a disposed on the first electrode 102 and the signal wiring TL and exposing the solder pattern 118 .

[0085] The light emitting element 10 may include a first conductive type semiconductor layer 140, an active layer 142 disposed on the first conductive type semiconductor layer 140, and a second conductive type semiconductor layer 144 disposed on the active layer 142. A first driving electrode 146 may be disposed on a lower portion of the first conductive type semiconductor layer 140 and a second driving electrode 148 may be disposed on an upper portion of the second conductive type semiconductor layer 144.

[0086] The light emitting element 100 may be formed on a silicon wafer by using a method such as metal organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), molecular beam epitaxy (MBE), hydride vapor phase epitaxy (HVPE), or sputtering.

[0087] The first conductive type semiconductor layer 140 may be implemented with a compound semiconductor such as a group III-V or group II-VI semiconductor, and may be doped with a first dopant. x1 In y1 Ga (1-x1-y1) The first conductive type semiconductor layer 140 may be formed of one or more of a semiconductor material of N (0≤x1≤1, 0≤y1≤1, 0≤x1+y1≤1), InAlGaN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP, but is not limited thereto. When the first dopant is an n-type dopant such as Si, Ge, Sn, Se, or Te, the first conductive type semiconductor layer 140 may be an n-type nitride semiconductor layer. However, when the first dopant is a p-type dopant, the first conductive type semiconductor layer 140 may be a p-type nitride semiconductor layer.

[0088] The active layer 142 is a layer where electrons (or holes) injected through the first conductive type semiconductor layer 140 meet holes (or electrons) injected through the second conductive type semiconductor layer 144. When the electrons and holes are recombined, the active layer 142 may be converted to a low energy level and may generate light having a corresponding wavelength.

[0089] The active layer 142 may have any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, or a quantum wiring structure, but the structure of the active layer 142 is not limited thereto.

[0090] The active layer 142 may generate light in a visible band. For example, the active layer 142 may output light in any one of blue, green, and red bands.

[0091] The second conductive semiconductor layer 144 may be disposed on the active layer 142. The second conductive semiconductor layer 144 may be implemented with a compound semiconductor such as a group III-V or group II-VI semiconductor, and the second conductive semiconductor layer 144 may be doped with a second dopant. The second conductive semiconductor layer 144 may be made of a material selected from a group having an empirical formula of In x2 Al y2 Ga 1-x2-y2 The second conductive type semiconductor layer 144 may be formed of a semiconductor material of N (0≤x2≤1, 0≤y2≤1, 0≤x2+y2≤1) or a material of AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, or Ba, the second conductive type semiconductor layer 144 doped with the second dopant may be a p-type nitride semiconductor layer. When the second dopant is an n-type dopant, the second conductive type semiconductor layer 144 may be an n-type nitride semiconductor layer.

[0092] Although the light emitting element has been described as having a vertical structure in which the driving electrodes 146 and 148 are disposed at the upper and lower portions of the light emitting structure in the embodiment, the light emitting element may have a lateral structure or a flip chip structure in addition to the vertical structure.

[0093] FIG. 7A to FIG. 7G is a schematic cross-sectional view illustrating a manufacturing process of a display device according to an embodiment. FIG. 7A to FIG. 7G A manufacturing process of the display device is described, but redundant descriptions of respective components will be omitted.

[0094] Reference Fig. 7A , a pixel driving circuit 200 may be formed on the substrate 20, and a buffer layer 202 may be formed on the pixel driving circuit 200. The pixel driving circuit 200 may receive a driving voltage, an image signal (digital signal), a synchronization signal synchronized with the image signal, etc., and may output an anode voltage and a cathode voltage of the light emitting element 100 to drive a plurality of pixels. The pixel driving circuit 200 may be disposed in the non-display area 14, or may be disposed below the display area 12.

[0095] Then, connection wirings RT1 and RT2 may be formed on the buffer layer 202, followed by an insulating layer 204. The connection wirings RT1 and RT2 may be electrically connected to the pixel driving circuit 200 by penetrating the buffer layer 202. In order to drive each pixel, the number of connection wirings RT1 and RT2 and the number of times the connection wirings are stacked may be changed in various ways. For example, the number of times the connection wirings RT1 and RT2 and the insulating layer 204 are stacked may be two or more times.

[0096] A plurality of bank patterns 112 may be provided on the insulating layer 204. During the transfer process of the light emitting element 100, the bank pattern 112 may guide the position where the light emitting element 100 is to be attached. Therefore, the position where the light emitting element 100 is transferred may be selected based on the bank pattern 112. The bank pattern 112 may be formed of an organic insulating material such as photosensitive photoacrylic or photosensitive polyimide, but is not limited thereto. According to an embodiment, the bank pattern 112 may be omitted.

[0097] An electrode material may be applied on the insulating layer 204 and the bank pattern 112. The applied electrode material may be patterned to form a plurality of first electrodes 102 and a contact electrode 106. The plurality of first electrodes 102 are regions where the light emitting element 100 is disposed, and the contact electrode 106 is a region electrically connected to the second electrode 104. Thereafter, a passivation layer 120 may be formed on the remaining electrode regions except for the regions where the plurality of first electrodes 102 and the contact electrode 106 are formed.

[0098] A solder pattern 118 may be formed on the first electrode 102. The solder pattern 118 may be made of indium (In), tin (Sn), or an alloy thereof, but is not limited thereto.

[0099] On each solder pattern 118, a light emitting element 100 (e.g., a red light emitting element 100R, a green light emitting element 100G, and a blue light emitting element 100B) may be transferred. For example, as shown, one light emitting element 100 may be transferred to one solder pattern 118. One pixel may include light emitting elements 100 of three colors. The first light emitting element may be red light emitting elements 110R and 110R', the second light emitting element may be green light emitting elements 110G and 110G', and the third light emitting element may be blue light emitting elements 110B and 110B'. Two light emitting elements may be mounted on each sub-pixel, but are not limited thereto.

[0100] The transfer method of the light emitting element 100 is not particularly limited, and various transfer methods can be used. For example, the light emitting element 100 grown on the semiconductor growth substrate may be first transferred to the transfer substrate, and then subsequently transferred to the substrate 20. In another example, the light emitting element 100 grown on the semiconductor growth substrate may be directly transferred to the substrate 20.

[0101] Reference Figure 7B After the light emitting element 100 is transferred, the first optical layer 136 may be formed to cover the side surfaces of the plurality of light emitting elements 100 and the bank pattern 112. In this case, the first optical layer 136 may cover between the plurality of light emitting elements 100 and between the plurality of bank patterns 112. At this time, the upper surface of the light emitting element 100 may be exposed to the upper portion of the first optical layer 136.

[0102] The first optical layer 136 may include an organic material. Fine metal particles such as titanium dioxide particles may be dispersed in the organic insulating material of the first optical layer 136. In this case, light emitted from the light emitting element 100 may be scattered by the fine metal particles dispersed in the first optical layer 136 and emitted.

[0103] Reference Figure 7C , after forming the first optical layer 136, the first component 122 may be disposed between the plurality of light emitting elements 100. The first component 122 may be disposed on the upper portion of the insulating layer 204 and the first electrode 102. The first component 122 may be formed of an organic film. The upper surface of the first component 122 may be formed to be equal to or higher than the height of the upper surface of the light emitting element 100. The side surface of the first component 122 may be tapered. The first component 122 may be formed in a variety of shapes including a lens shape.

[0104] Reference Fig.7D , a metal layer 124 may be provided on the first component 122. The metal layer 124 may be formed to surround the upper surface and the side of the first component 122. The metal layer 124 may be formed of, for example, but not limited to, titanium (Ti) or aluminum (Al) having high light reflectivity. The metal layer 124 may reflect light emitted from the side of the light emitting element 100, thereby increasing light extraction efficiency. According to an embodiment, the metal layer 124 may be referred to as a reflective layer or a light reflecting layer, but is not limited to these terms.

[0105] Reference Fig. 7E , the second electrode 104 may be disposed on the metal layer 124, the light emitting element 100 and the first optical layer 136. The second electrode 104 may be disposed to cover the metal layer 124, the light emitting element 100 and the first optical layer 136.

[0106] Reference Figure 7F , a second optical layer 127 may be disposed on at least a portion of the second electrode 104. For example, the second optical layer 127 may be formed to cover the second electrode 104 disposed between the light emitting element 100 and the first component 122. When the second optical layer 127 is disposed between the light emitting element 100 and the first component 122, the upper surface of the second optical layer 127 may be disposed to be flat or coplanar with the upper surface of the second electrode 104 on the light emitting element 100, as shown.

[0107] Reference Figure 7G, a black matrix 128 may be formed to cover a portion of the second electrode 104 and the second optical layer 127. The black matrix 128 may be disposed between a plurality of light emitting elements 100. The black matrix 128 may cover at least a portion of an upper surface of the second electrode 104. The black matrix 128 may include a black pigment. The black matrix 128 may block light. By blocking light with the black matrix 128, the problem of mixing of light emitted from adjacent light emitting elements 100 due to the first optical layer 128 may be improved.

[0108] Figure 8 yes Figure 5 Another embodiment of .

[0109] Reference Figure 8 , the black matrix 128 may be disposed on the upper portion of the plurality of first components 122. For example, as shown, the black matrix 128 may be formed to cover the plurality of first components 122 and the green light emitting element 100G. The black matrix 128 may be disposed on the upper portion of the second electrode 104 and the second optical layer 127. The black matrix 128 may be disposed on one light emitting element 100 (e.g., the green light emitting element 100G), and thus color mixing between light emitting elements 100 emitting different colors may be prevented.

[0110] Fig. 9 yes Figure 5 Yet another implementation method.

[0111] Reference Fig. 9 , the metal layer 124 may be provided in a circular shape on the upper portion of the first member 122. Although the above modified embodiment is described in a structure in which the metal layer 124 is provided in a circular shape, the shape of the metal layer 124 is not limited thereto.

[0112] The display device according to the embodiments of the present disclosure can be applied to mobile devices, video phones, smart watches, watch phones, wearable devices, foldable devices, rollable devices, bendable devices, flexible devices, bending devices, sliding devices, variable devices, electronic notebooks, electronic books, portable multimedia players (PMP), personal digital assistants (PDAs), MP3 players, mobile medical devices, desktop PCs, laptop PCs, netbook computers, workstations, navigation systems, vehicle display devices, theater display devices, televisions, wallpaper devices, signage devices, gaming devices, laptops, displays, cameras, video cameras, home appliances, etc. In addition, the display device according to one or more embodiments of the present application can be applied to organic light emitting lighting devices or inorganic light emitting lighting devices.

[0113] A display device according to various embodiments of the present disclosure may be described as follows.

[0114] A display device according to an embodiment of the present disclosure may include: a plurality of first electrodes and contact electrodes arranged on a substrate; a first embankment and a second embankment arranged on the substrate; a first light-emitting element arranged on the first embankment; a second light-emitting element arranged on the second embankment; a first optical layer and a first component arranged between the first light-emitting element and the second light-emitting element; and a second electrode arranged on the first light-emitting element and the second light-emitting element, wherein the second electrode extends outward from the first optical layer arranged between the first light-emitting element and the second light-emitting element and is electrically connected to the contact electrode.

[0115] According to one embodiment of the present disclosure, the display device may further include a second optical layer disposed on an upper portion of a portion of the second electrode.

[0116] According to one embodiment of the present disclosure, each of the first optical layer and the second optical layer may include light scattering particles.

[0117] According to one embodiment of the present disclosure, at least a portion of an upper surface of the first member may be equal to or higher than an upper surface of the light emitting element.

[0118] According to one embodiment of the present disclosure, the display device may further include a metal layer surrounding at least a portion of the first member.

[0119] According to one embodiment of the present disclosure, a black matrix may be disposed on an upper portion of the metal layer.

[0120] According to an embodiment of the present disclosure, the display device may further include a plurality of signal wirings extending between the first bank and the second bank and connected to the plurality of first electrodes.

[0121] According to an embodiment of the present disclosure, the contact electrode may be provided between the plurality of signal wirings.

[0122] According to one embodiment of the present disclosure, the second electrode may include a plurality of second electrodes provided to be spaced apart from each other for respective pixel rows of pixels, and each of the plurality of second electrodes is electrically connected to the contact electrode.

[0123] According to one embodiment of the present disclosure, at least some of the plurality of second electrodes are disposed on the first and second light emitting elements and an upper portion of the metal layer surrounding at least a portion of the first component and on a side of the first optical layer.

[0124] According to one embodiment of the present disclosure, the display device may further include: an insulating layer arranged on the substrate; a plurality of connecting wirings arranged between the substrate and the insulating layer; and a pixel driving circuit connected to the plurality of connecting wirings, wherein the plurality of connecting wirings are electrically connected to the plurality of first electrodes and the contact electrodes.

[0125] According to one embodiment of the present disclosure, each of the first light emitting element and the second light emitting element may be connected through a different connection wiring among the plurality of connection wirings.

[0126] According to one embodiment of the present disclosure, each of the first light emitting element and the second light emitting element may include an inorganic light emitting diode.

[0127] According to one embodiment of the present disclosure, the metal layer may reflect light emitted from the sides of the first and second light emitting elements toward upper portions of the first and second light emitting elements.

[0128] According to one embodiment of the present disclosure, the metal layer may be provided in a circular shape.

[0129] The effects of the present specification are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the description in the claims.

[0130] Although the embodiments of the present disclosure have been described in more detail with reference to the accompanying drawings, the present disclosure is not necessarily limited to these embodiments, and various modifications may be made without departing from the technical concept 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 are intended to describe it, and the scope of the technical spirit of the present disclosure is not limited to these embodiments. Therefore, it should be understood that the above-mentioned embodiments are illustrative and not restrictive in all aspects.

Claims

1. A display device, comprising: A plurality of first electrodes and contact electrodes are disposed on the substrate; a first bank and a second bank disposed on the substrate; a first light emitting element disposed on the first bank; a second light emitting element disposed on the second bank; a first optical layer and a first component disposed between the first light emitting element and the second light emitting element; as well as a second electrode disposed on the first light emitting element and the second light emitting element, The second electrode extends outward from the first optical layer disposed between the first light emitting element and the second light emitting element and is electrically connected to the contact electrode.

2. The display device according to claim 1, further comprising: A second optical layer is disposed on an upper portion of a portion of the second electrode. 3 . The display device according to claim 2 , wherein each of the first optical layer and the second optical layer comprises light scattering particles. 4 . The display device according to claim 1 , wherein at least a portion of an upper surface of the first member is equal to or higher than an upper surface of the light emitting element.

5. The display device according to claim 1, further comprising: A metal layer surrounds at least a portion of the first component. The display device according to claim 5 , wherein a black matrix is ​​disposed on an upper portion of the metal layer.

7. The display device according to claim 1, further comprising: A plurality of signal wirings extend between the first bank and the second bank and are connected to the plurality of first electrodes. 8 . The display device according to claim 7 , wherein the contact electrode is provided between the plurality of signal wirings.

9. The display device according to claim 1, wherein: The second electrode includes a plurality of second electrodes provided separately from each other for respective pixel rows of pixels, and Each of the plurality of second electrodes is electrically connected to the contact electrode.

10. The display device according to claim 9, wherein at least some of the plurality of second electrodes are disposed on the first and second light emitting elements and an upper portion of a metal layer surrounding at least a portion of the first component, and on a side surface of the first optical layer.

11. The display device according to claim 1, further comprising: An insulating layer disposed on the substrate; a plurality of connection wirings disposed between the substrate and the insulating layer; and a pixel driving circuit connected to the plurality of connection wirings, The plurality of connection wirings are electrically connected to the plurality of first electrodes and the contact electrode. 12 . The display device according to claim 11 , wherein the first light emitting element and the second light emitting element are each connected by a different connection wiring among the plurality of connection wirings. 13 . The display device according to claim 1 , wherein each of the first light emitting element and the second light emitting element comprises an inorganic light emitting diode. 14 . The display device according to claim 5 , wherein the metal layer reflects light emitted from the side surfaces of the first light emitting element and the second light emitting element toward upper portions of the first light emitting element and the second light emitting element.

15. The display device according to claim 5, wherein the metal layer is provided in a circular shape.

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