Display device and method of manufacturing same

Abstract

The invention relates to a display device and a method of manufacturing the same. The display device comprises a first light emitting diode and a second light emitting diode, and the first light emitting diode comprises a first lower electrode, a first inorganic functional layer, a quantum dot emission layer, a second inorganic functional layer and a first upper electrode. Wherein the second light emitting diode includes a second lower electrode, a first organic functional layer, an organic emission layer, a second organic functional layer, and a second upper electrode, in which a level of an upper surface of the first inorganic functional layer is higher at an edge portion of the first inorganic functional layer than at a center portion of the first inorganic functional layer, and a level of an upper surface of the first organic functional layer is the same at a center portion of the first organic functional layer and at an edge portion of the first organic functional layer.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0130466 filed in the Korean Intellectual Property Office on September 27, 2023, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] Aspects of one or more embodiments are directed to a display device and a method of manufacturing the display device. Background Art

[0004] In general, a display device includes a light emitting diode and a thin film transistor located on a substrate, and operates by causing the light emitting diode to emit light. The light emitting diode converts electrical energy into light energy. Examples of light emitting diodes include organic light emitting diodes whose emission materials are organic materials and quantum dot light emitting diodes whose emission materials are quantum dots.

[0005] For example, each pixel of the display device may include a light emitting diode, wherein an interlayer including an emission layer is arranged between a lower electrode and an upper electrode. The display device generally controls the emission or luminescence degree of light of each pixel by a thin film transistor electrically connected to the lower electrode. Some layers included in the interlayer of the light emitting diode may be provided together in a plurality of light emitting diodes.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background technology, and so the information discussed in this Background section does not necessarily constitute prior art. Summary of the invention

[0007] One or more embodiments include a display device including a light emitting diode having high light emitting efficiency and a long life span. However, the one or more embodiments are merely examples, and the scope of the present disclosure is not limited thereto.

[0008] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0009] According to one or more embodiments, a display device includes: a first light-emitting diode and a second light-emitting diode, each of which is located on a substrate, and the first light-emitting diode and the second light-emitting diode emit light of different colors from each other, wherein the first light-emitting diode includes: a first lower electrode; a first inorganic functional layer, located on the first lower electrode and including an inorganic material; a quantum dot emission layer, located on the first inorganic functional layer and including quantum dots; a second inorganic functional layer, located on the quantum dot emission layer and including an inorganic material; and a first upper electrode, located on the second inorganic functional layer, wherein the second light-emitting diode includes: a second lower electrode; a first organic functional layer, located on the second lower electrode and including an organic material; an organic emission layer, located on the first organic functional layer and including an organic material; a second organic functional layer, located on the organic emission layer and including an organic material; and a second upper electrode, located on the second organic functional layer, wherein the level of the upper surface of the first inorganic functional layer is higher at the edge portion of the first inorganic functional layer than at the center portion of the first inorganic functional layer, and the level of the upper surface of the first organic functional layer is the same at the center portion of the first organic functional layer and at the edge portion of the first organic functional layer.

[0010] According to one or more embodiments, the level of the upper surface of the quantum dot emission layer may be higher at the edge portion of the quantum dot emission layer than at the center portion of the quantum dot emission layer, and the level of the upper surface of the organic emission layer may be the same at the center portion of the organic emission layer and at the edge portion of the organic emission layer.

[0011] According to one or more embodiments, the level of the upper surface of the second inorganic functional layer may be the same at the center portion of the second inorganic functional layer and at the edge portion of the second inorganic functional layer, and the level of the upper surface of the second organic functional layer may be the same at the center portion of the second organic functional layer and at the edge portion of the second organic functional layer.

[0012] According to one or more embodiments, the first inorganic functional layer may include at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze, and hydrogen vanadium bronze.

[0013] According to one or more embodiments, the second inorganic functional layer may include at least one of titanium oxide, zinc oxide, zinc magnesium oxide, and tin oxide.

[0014] According to one or more embodiments, the first inorganic functional layer may include at least one of titanium oxide, zinc oxide, zinc magnesium oxide, and tin oxide.

[0015] According to one or more embodiments, the second inorganic functional layer may include at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze, and hydrogen vanadium bronze.

[0016] According to one or more embodiments, the pixel device may further include a pixel defining layer located on the substrate, the pixel defining layer covering an edge of each of the first lower electrode and the second lower electrode, and including a first opening exposing a central portion of the first lower electrode and a second opening exposing a central portion of the second lower electrode.

[0017] According to one or more embodiments, the first inorganic functional layer, the quantum dot emission layer, and the second inorganic functional layer may be arranged in the first opening of the pixel defining layer, and the first organic functional layer, the organic emission layer, and the second organic functional layer may be arranged in the second opening of the pixel defining layer.

[0018] According to one or more embodiments, the first upper electrode and the second upper electrode may be provided integrally.

[0019] According to one or more embodiments, a method for manufacturing a display device includes forming a first lower electrode and a second lower electrode on a substrate, performing an inkjet printing process on the first lower electrode to form a first inorganic functional layer including an inorganic material, performing an inkjet printing process on the first inorganic functional layer to form a quantum dot emission layer including quantum dots, performing a vapor deposition process on the quantum dot emission layer to form a second inorganic functional layer, forming a first organic functional layer including an organic material on the second lower electrode, forming an organic emission layer on the first organic functional layer, forming a second organic functional layer including an organic material on the organic emission layer, and forming an upper electrode on the second inorganic functional layer and the second organic functional layer.

[0020] According to one or more embodiments, the first organic functional layer may be formed by a vapor deposition process.

[0021] According to one or more embodiments, the forming of the first organic functional layer may be performed after the forming of the second inorganic functional layer.

[0022] According to one or more embodiments, the organic emission layer and the second organic functional layer may be formed by a vapor deposition process.

[0023] According to one or more embodiments, the first inorganic functional layer may include at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze, and hydrogen vanadium bronze.

[0024] According to one or more embodiments, the second inorganic functional layer may include at least one of titanium oxide, zinc oxide, zinc magnesium oxide, and tin oxide.

[0025] According to one or more embodiments, the first inorganic functional layer may include at least one of titanium oxide, zinc oxide, zinc magnesium oxide, and tin oxide.

[0026] According to one or more embodiments, the second inorganic functional layer may include at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze, and hydrogen vanadium bronze.

[0027] According to one or more embodiments, the method of manufacturing a display device may further include forming a pixel defining layer on the substrate, the pixel defining layer covering an edge of each of the first lower electrode and the second lower electrode, and including a first opening exposing a central portion of the first lower electrode and a second opening exposing a central portion of the second lower electrode.

[0028] According to one or more embodiments, the first inorganic functional layer, the quantum dot emission layer, and the second inorganic functional layer may be arranged in the first opening of the pixel defining layer, and the first organic functional layer, the organic emission layer, and the second organic functional layer may be arranged in the second opening of the pixel defining layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0030] Figure 1 is a schematic perspective view of a display device according to an embodiment;

[0031] Figure 2 For and including Figure 1 An equivalent circuit diagram of a pixel circuit in which a light emitting diode in a pixel of a display device is electrically connected;

[0032] Figure 3A and Figure 3B is a schematic cross-sectional view of a display device according to an embodiment;

[0033] Figure 4 for Figure 1 A schematic enlarged plan view of region A in FIG.

[0034] Figure 5 For along Figure 4 A schematic cross-sectional view of the display device taken along line II'; and

[0035] Figures 6 to 13 Each is a schematic cross-sectional view of a manufacturing process of a display device according to some embodiments. DETAILED DESCRIPTION

[0036] Reference will now be made in more detail to aspects of some embodiments, examples of which are illustrated in the accompanying drawings, wherein the same reference numerals refer to the same elements throughout. In this regard, the present embodiment may have different forms and should not be construed as being limited to the description set forth herein. Accordingly, the following merely describes the embodiments by reference to the figures to explain aspects of the present description. As used herein, the term "and / or" includes any and all combinations of one or more associated enumerated items. Throughout this disclosure, the expression "at least one of a, b, and c" indicates only a, only b, only c, both a and b, both a and c, both b and c, all a, b, and c, or variations thereof.

[0037] Because the present disclosure may have various different modified embodiments, aspects of some example embodiments are illustrated in the drawings and described in the detailed description. When referring to the embodiments described with reference to the drawings, the effects and characteristics of the present disclosure and the methods for achieving these will be apparent. However, the present disclosure may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0038] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings, wherein the same or corresponding elements are denoted by the same reference numerals throughout and repeated descriptions thereof are omitted.

[0039] In the following embodiments, the terms "first" and "second" are not used in a restrictive sense, but are used to distinguish one component from another component. As used herein, the singular expressions "a", "an" and "the" are intended to include plural forms as well, unless the context clearly indicates otherwise.

[0040] It will be further understood that the terms "comprises" and / or "comprising" as used herein indicate the presence of the recited features or components, but do not preclude the presence or addition of one or more other features or components. It will be understood that when a layer, region, or element is referred to as being formed "on" another layer, region, or element, it may be formed directly or indirectly on the other layer, region, or element. That is, for example, intervening layers, regions, or elements may be present.

[0041] In the drawings, the size of the components may be enlarged or reduced for convenience of description. In other words, since the size (eg, thickness) of the components in the drawings is arbitrarily explained for convenience of description, the present invention is not necessarily limited to what is shown.

[0042] When certain embodiments can be implemented in different ways, a specific process can be performed in a different order than the described order. For example, two processes described in succession can be performed substantially simultaneously or in a reverse order to the described order.

[0043] In the embodiments below, it will be understood that when an element, region or layer is referred to as being connected to another element, region or layer, it may be directly and / or indirectly connected to another element, region or layer. For example, it will be understood that in this specification, when an element, region or layer is referred to as being in contact with or electrically connected to another element, region or layer, it may be directly and / or indirectly in contact with or electrically connected to another element, region or layer.

[0044] Figure 1 is a schematic perspective view of a display device according to some embodiments.

[0045] refer to Figure 1 , the display device 1 may include a display area DA and a non-display area NDA located on a substrate 100 .

[0046] An image may be realized in the display area DA. In the display area DA, a plurality of pixels PX are two-dimensionally arranged on a plane. The display device 1 may display an image by using light emitted from the plurality of pixels PX.

[0047] The non-display area NDA does not display an image and does not include the pixels PX. The entire display area DA may be surrounded by the non-display area NDA. A driver or voltage wiring may be included in the non-display area NDA to provide an electrical signal or power to the pixels PX. A pad portion may be arranged in the non-display area NDA, wherein an electronic component, a printed circuit board, etc. are electrically connected to the pad portion.

[0048] The display area DA may have a polygonal shape. Figure 1 As shown in , the display area DA may have a rectangular shape in which the horizontal length is greater than the vertical length. Alternatively, the display area DA may have a square shape. Alternatively, the display area DA may have various shapes, such as an ellipse or a circle.

[0049] Figure 2 For and including Figure 1 An equivalent circuit diagram of a pixel circuit in which a light emitting diode in a pixel of a display device is electrically connected.

[0050] refer to Figure 2 , the pixel PX may include a pixel circuit PC, a display element connected to the pixel circuit PC, for example, a light emitting diode LED. The pixel circuit PC may include a first thin film transistor T1, a second thin film transistor T2, and a storage capacitor Cst. Each pixel PX may emit light, such as red light, green light, or blue light, or emit red light, green light, blue light, or white light through a light emitting diode LED.

[0051] The second thin film transistor T2 may be a switching thin film transistor, may be connected to the scan line SL and the data line DL, and may be configured to transfer a data voltage or a data signal Dm input from the data line DL to the first thin film transistor T1 according to a switching voltage or a switching signal Sn input from the scan line SL. The storage capacitor Cst may be connected to the second thin film transistor T2 and the driving voltage line PL, and may be configured to store a voltage corresponding to a difference between a voltage received from the second thin film transistor T2 and a first power supply voltage ELVDD supplied to the driving voltage line PL.

[0052] The first thin film transistor T1 may be a driving thin film transistor, may be connected to the driving voltage line PL and the storage capacitor Cst, and may be configured to control a driving current flowing from the driving voltage line PL through the light emitting diode LED according to the value of the voltage stored in the storage capacitor Cst. The light emitting diode LED may emit light with a certain brightness according to the driving current. An upper electrode (e.g., cathode) of the light emitting diode LED may receive a second power supply voltage ELVSS.

[0053] Figure 2 The pixel circuit PC including two thin film transistors and one storage capacitor is explained, but according to some embodiments, the number of thin film transistors and the storage capacitor may be changed according to the design of the pixel circuit PC.

[0054] Figure 3A is a schematic cross-sectional view of a display device 1 according to some embodiments, and Figure 3B is a schematic cross-sectional view of a display device 1 according to some embodiments.

[0055] refer to Figure 3A The display layer DPL and the thin film encapsulation layer TFE may be disposed on the substrate 100 of the display device 1. The display layer DPL may include: a pixel circuit layer PCL including a pixel circuit and an insulating layer; and a display element layer DEL located on the pixel circuit layer PCL and including a plurality of display elements.

[0056] The substrate 100 may include glass, metal, or a polymer resin. The polymer resin may include polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, cellulose acetate propionate, or a mixture thereof. However, the substrate 100 may have a multilayer structure including two layers and an isolation layer therebetween, each of the two layers may include a polymer resin, and the isolation layer may include an inorganic material such as silicon oxide (SiO x ), Silicon Nitride (SiN x ) and silicon oxynitride (SiON), and various modifications may be made.

[0057] The display element layer DEL may include a light emitting element, for example, an organic light emitting element, a quantum dot light emitting element, etc. The pixel circuit layer PCL may include a pixel circuit and an insulating layer connected to a light emitting diode. For example, the pixel circuit layer PCL may include a plurality of transistors, a plurality of storage capacitors, and an insulating layer between the transistors and the storage capacitors.

[0058] The display element may be covered with an encapsulation member (such as a thin film encapsulation layer TFE). The thin film encapsulation layer TFE may include at least one inorganic encapsulation layer and at least one organic encapsulation layer to cover the display element layer DEL. The inorganic encapsulation layer may include an inorganic insulating material, such as aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ), zinc oxide (ZnO x , which may be ZnO and / or ZnO 2 ), silicon oxide (SiO x ), Silicon Nitride (SiN x ) or silicon oxynitride (SiON). The organic encapsulation layer may include a polymer-based material. Examples of polymer-based materials may include acrylic resin, epoxy resin, polyimide, and polyethylene. According to some embodiments, the organic encapsulation layer may include acrylate.

[0059] refer to Figure 3B , the display layer DPL and the sealing substrate 400 may be located on the substrate 100 of the display device 1. The sealing member 300 may be arranged between the substrate 100 and the sealing substrate 400. The sealing substrate 400 may be a transparent member. The substrate 100 and the sealing substrate 400 may be connected to each other with the sealing member 300, and the internal space between the substrate 100 and the sealing substrate 400 may be sealed. In this case, an absorbent or a filler may be arranged in the internal space. The sealing member 300 may include a sealant, and according to some embodiments, the sealing member 300 may include a material that can be hardened by a laser. For example, the sealing member 300 may include glass frit. For example, the sealing member 300 may include an organic sealant (such as urethane resin, epoxy resin or acrylic resin) or an inorganic sealant (such as silicon). As urethane resin, for example, urethane acrylate may be used. As acrylic resin, for example, butyl acrylate, ethylhexyl acrylate, etc. may be used. The sealing member 300 may include a material that is hardened by heating.

[0060] According to some embodiments, the display element layer DEL may be Figure 3B The sealing substrate 400 and the sealing member 300 and Figure 3A The thin film encapsulation layer is covered together with TFE.

[0061] The touch electrode layer may be located on the thin film encapsulation layer TFE and / or the sealing substrate 400, and the optical function layer may be located on the touch electrode layer. The touch electrode layer may obtain coordinate information based on external input (e.g., a touch event). The optical function layer may reduce the reflectivity of light (external light) incident from the outside toward the display device 1. Or the optical function layer may improve the color purity of the light emitted from the display device 1. According to some embodiments, the optical function layer may include a retarder and / or a polarizer. The retarder may be a film type or a liquid crystal coating type, and may include a λ / 2 retarder and / or a λ / 4 retarder. The polarizer may also be a film type or a liquid crystal coating type. The film type may include a stretched synthetic resin film, and the liquid crystal coating type may include liquid crystals arranged in a certain arrangement. The retarder and the polarizer may further include a protective film.

[0062] According to some embodiments, the optical functional layer may include a black matrix and a color filter. The color filter may be arranged in consideration of the color of the light emitted from each pixel in the display device 1. Each color filter may include a red, green or blue pigment or dye. Alternatively, in addition to the above-mentioned pigment or dye, each color filter may further include quantum dots. Alternatively, some color filters may not contain the above-mentioned pigment or dye, and may include scattering particles, such as titanium oxide particles.

[0063] Figure 4 for Figure 1 Schematic enlarged plan view of area A in FIG.

[0064] refer to Figure 4 , the display device 1 may include a plurality of pixels PX ( Figure 1 ). Multiple pixels PX( Figure 1 ) may include a first pixel PX1, a second pixel PX2, and a third pixel PX3. The first pixel PX1 may include a first light emitting diode LED1 ( Figure 5 ), the second pixel PX2 may include a second light emitting diode LED2 ( Figure 5), and the third pixel PX3 may include a third light emitting diode LED3. The first pixel PX1, the second pixel PX2, and the third pixel PX3 may emit light of different colors. For example, the first pixel PX1 may emit red light, the second pixel PX2 may emit green light, and the third pixel PX3 may emit blue light, but this embodiment is only an example and is not limited thereto according to the embodiments of the present disclosure. For example, the first pixel PX1 may emit green light, the second pixel PX2 may emit blue light, and the third pixel PX3 may emit red light. For example, the first pixel PX1 may emit red light, the second pixel PX2 may emit blue light, and the third pixel PX3 may emit green light. Red light belongs to a wavelength band ranging from 580 nanometers (nm) (or about 580 nm) to 780 nm (or about 780 nm), blue light belongs to a wavelength band ranging from 380 nm (or about 380 nm) to 495 nm (or about 495 nm), and green light belongs to a wavelength band ranging from 495 nm (or about 495 nm) to 580 nm (or about 580 nm).

[0065] Each light emitting diode may include a lower electrode, an upper electrode and an interlayer therebetween. Accordingly, the first pixel PX1 may include a first light emitting diode LED1 ( Figure 5 ) of the first lower electrode 210a, the second pixel PX2 may include a second light emitting diode LED2 ( Figure 5 ) of the second lower electrode 210b, and the third pixel PX3 may include a third light emitting diode LED3 ( Figure 5 ) of the third lower electrode 210c. The first lower electrode 210a, the second lower electrode 210b and the third lower electrode 210c may be formed on the substrate 100 ( Figure 5 ) are spaced apart from each other on the substrate 100 ( Figure 5 ) direction or substrate 100( Figure 5 ) when viewed in the normal direction of the substrate 100 ( Figure 5 ) direction, A and B are separated from each other".

[0066] The pixel defining layer 120 may be located on the first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c, and may cover each of the first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c. The pixel defining layer 120 may have an opening OP, and the opening OP includes a first opening 120OP1, a second opening 120OP2, and a third opening 120OP3. The pixel defining layer 120 may include a first opening 120OP1 exposing a central portion of the first lower electrode 210a, a second opening 120OP2 exposing a central portion of the second lower electrode 210b, and a third opening 120OP3 exposing a central portion of the third lower electrode 210c.

[0067] According to some embodiments, the emission layer emitting light may be located in the first opening 120OP1, the second opening 120OP2, and the third opening 120OP3, respectively. The upper electrode may be located on the emission layer. As described above, the stacked structure of the lower electrode, the emission layer, and the upper electrode may form a light-emitting diode. One opening of the pixel defining layer 120 corresponds to one light-emitting diode and may define one emission area.

[0068] For example, an emission layer emitting red light is arranged in the first opening 120OP1, so that the first opening 120OP1 can define a first emission area EA1. Similarly, an emission layer emitting green light is arranged in the second opening 120OP2, so that the second opening 120OP2 can define a second emission area EA2. An emission layer emitting blue light is arranged in the third opening 120OP3, so that the third opening 120OP3 can define a third emission area EA3. Accordingly, the size of the area of ​​the first opening 120OP1 may be the same as the size of the area of ​​the first emission area EA1. The size of the area of ​​the second opening 120OP2 may be the same as the size of the area of ​​the second emission area EA2. The size of the area of ​​the third opening 120OP3 may be the same as the size of the area of ​​the third emission area EA3.

[0069] When the angle is perpendicular to the substrate 100 ( Figure 5 ) direction( Figure 5 When viewed from a direction perpendicular to the substrate 100 ( z direction), each of the first opening 120OP1, the second opening 120OP2, and the third opening 120OP3 may have a polygonal shape. Figure 5 ) direction( Figure 5 When viewed in the z direction (in the middle), the first emission area EA1, the second emission area EA2 and the third emission area EA3 may each have a polygonal shape. Figure 4 It is explained that when the substrate 100 ( Figure 5 ) direction( Figure 5 When viewed from a direction perpendicular to the substrate 100 ( z direction), the first emission area EA1, the second emission area EA2 and the third emission area EA3 each have a rectangular shape, in particular, a rectangular shape with rounded corners, but the present disclosure is not limited thereto. Figure 5 ) direction( Figure 5 When viewed in the z direction (in the middle), the first emission area EA1, the second emission area EA2 and the third emission area EA3 may each have a circular or elliptical shape.

[0070] Figure 4It is explained that the first pixel PX1, the second pixel PX2, and the third pixel PX3 are arranged in a stripe structure, but the embodiment is not limited thereto. For example, the first pixel PX1, the second pixel PX2, and the third pixel PX3 may be arranged in various pixel array structures, such as structure, mosaic structure or delta structure, etc.

[0071] Figure 5 For along Figure 4 Schematic cross-sectional view of the display device taken along line II'.

[0072] refer to Figure 5 The display device 1 may include a substrate 100, a pixel circuit layer PCL on the substrate 100, and a display element layer DEL on the pixel circuit layer PCL. According to some embodiments, the display device 1 may further include a thin film encapsulation layer TFE on the display element layer DEL.

[0073] The pixel circuit layer PCL may include a first transistor TR1, a second transistor TR2, and a third transistor TR3, a buffer layer 111 disposed below and / or above the components of the transistor, a first gate insulating layer 113, a second gate insulating layer 115, an interlayer insulating layer 117, and a planarization layer 119. Here, the first transistor TR1, the second transistor TR2, and the third transistor TR3 may each correspond to Figure 2 Since the structures of the second transistor TR2 and the third transistor TR3 are the same as or similar to the structure of the first transistor TR1, repeated descriptions thereof are omitted.

[0074] The buffer layer 111 may include an inorganic insulating material (such as SiN x , SiON or SiO x ), and may have a single-layer or multi-layer structure including the above-mentioned inorganic insulating material. The buffer layer 111 may planarize the upper surface of the substrate 100, and may prevent, reduce or minimize the penetration of pollutants or impurities from the substrate 100, etc. into the semiconductor layer Act.

[0075] The first transistor TR1 may include a semiconductor layer Act, and the semiconductor layer Act may include polysilicon. Alternatively, the semiconductor layer Act may include amorphous silicon, an oxide semiconductor material, or an organic semiconductor material.

[0076] The gate electrode GE may overlap a portion of the semiconductor layer Act. The gate electrode GE may include a conductive material. For example, the gate electrode GE may include a conductive material such as molybdenum (Mo), aluminum (Al), or titanium (Ti), and may have a multilayer structure or a single layer structure including the above materials.

[0077] The first gate insulating layer 113 between the semiconductor layer Act and the gate electrode GE may include an inorganic insulating material, such as silicon oxide (SiO x ), Silicon Nitride (SiN x ), silicon oxynitride (SiON), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ) or zinc oxide (ZnO x , which may be ZnO and / or ZnO 2 )wait.

[0078] The second gate insulating layer 115 may cover the gate electrode GE. Similar to the first gate insulating layer 113, the second gate insulating layer 115 may include an inorganic insulating material such as SiO x 、SiN x 、SiON、Al 2 O 3 、TiO 2 、 2 O 5 , HfO 2 or ZnO x wait.

[0079] The second capacitor electrode CE2 of the storage capacitor Cst may be located on the second gate insulating layer 115. The second capacitor electrode CE2 may overlap the gate electrode GE thereunder. In this case, the gate electrode GE and the second capacitor electrode CE2 overlapping each other with the second gate insulating layer 115 therebetween may form the storage capacitor Cst. That is, the gate electrode GE may serve as the first capacitor electrode CE1 of the storage capacitor Cst.

[0080] As described above, the storage capacitor Cst may overlap with the first transistor TR1. According to some embodiments, the storage capacitor Cst may not overlap with the first transistor TR1.

[0081] The second capacitor electrode CE2 may include aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W) and / or copper (Cu), and may have a single-layer or multi-layer structure including the above materials.

[0082] The interlayer insulating layer 117 may cover the second capacitor electrode CE2. The interlayer insulating layer 117 may include an inorganic insulating material such as SiO x 、SiN x 、SiON、Al2 O 3 、TiO 2 、 2 O 5 , HfO 2 or ZnO x The interlayer insulating layer 117 may have a single-layer or multi-layer structure including the above-mentioned inorganic insulating material.

[0083] The drain electrode SD1 and the source electrode SD2 may each be located on the interlayer insulating layer 117. The drain electrode SD1 and the source electrode SD2 may each be electrically connected to the semiconductor layer Act through a contact hole included in the first gate insulating layer 113, the second gate insulating layer 115, and the interlayer insulating layer 117. The drain electrode SD1 and the source electrode SD2 may include a material having good conductivity. The drain electrode SD1 and the source electrode SD2 may include a conductive material including Mo, Al, Cu, Ti, etc., and have a single-layer or multi-layer structure including the above materials. For example, the drain electrode SD1 and the source electrode SD2 may have a multi-layer structure of Ti / Al / Ti. According to some embodiments, one of the drain electrode SD1 and the source electrode SD2 may be omitted, and a portion of the semiconductor layer Act may be conductive and replace the omitted component.

[0084] The planarization layer 119 may cover the first transistor TR1 and include a contact hole exposing a portion of the first transistor TR1. The planarization layer 119 may include an organic insulating layer. The planarization layer 119 may include an organic insulating material, such as a general polymer (such as polymethyl methacrylate (PMMA) or polystyrene (PS)), a polymer derivative having a phenolic group, an acrylic polymer, an imide polymer, an aromatic ether polymer, an amide polymer, a fluorine polymer, a paraxylene polymer, a vinyl alcohol polymer, or a blend thereof.

[0085] The display element layer DEL may be located on the pixel circuit layer PCL. The display element layer DEL may include a first light emitting diode LED1, a second light emitting diode LED2, and a third light emitting diode LED3. The display element layer DEL may include a quantum dot light emitting diode and an organic light emitting diode including an emission layer. For example, the first light emitting diode LED1 and the second light emitting diode LED2 may be quantum dot light emitting diodes, and the third light emitting diode LED3 may be an organic light emitting diode. However, the embodiments according to the present disclosure are not limited thereto, and the combination of the quantum dot light emitting diode and the organic light emitting diode may be modified in various ways. For example, the first light emitting diode LED1 may be a quantum dot light emitting diode, and the second light emitting diode LED2 and the third light emitting diode LED3 may be organic light emitting diodes. The quantum dot light emitting diode may include an emission layer including quantum dots, and the organic light emitting diode may not include quantum dots and include an emission layer including an organic material. Hereinafter, for the convenience of explanation, it is described based on the assumption that the first light emitting diode LED1 and the second light emitting diode LED2 are each quantum dot light emitting diodes and the third light emitting diode LED3 is an organic light emitting diode.

[0086] Each of the first light emitting diode LED1, the second light emitting diode LED2 and the third light emitting diode LED3 may include a lower electrode, an interlayer and an upper electrode. In addition, each of the first light emitting diode LED1, the second light emitting diode LED2 and the third light emitting diode LED3 may further include a first inorganic functional layer between the lower electrode and the interlayer and a second inorganic functional layer between the upper electrode and the interlayer.

[0087] The first light emitting diode LED1 may include a first lower electrode 210a, a first interlayer 220a on the first lower electrode 210a, and a first upper electrode 230a on the first interlayer 220a. The first light emitting diode LED1 may further include a first-1 functional layer 215a between the first lower electrode 210a and the first interlayer 220a, and a second-1 functional layer 225a between the first upper electrode 230a and the first interlayer 220a.

[0088] The second light emitting diode LED2 may include a second lower electrode 210b, a second interlayer 220b on the second lower electrode 210b, and a second upper electrode 230b on the second interlayer 220b. The second light emitting diode LED2 may further include a first-2 functional layer 215b between the second lower electrode 210b and the second interlayer 220b, and a second-2 functional layer 225b between the second upper electrode 230b and the second interlayer 220b.

[0089] The third light emitting diode LED3 may include a third lower electrode 210c, a third interlayer 220c, and a third upper electrode 230c. The third light emitting diode LED3 may further include a first-3 functional layer 215c between the third lower electrode 210c and the third interlayer 220c, and a second-3 functional layer 225c between the third upper electrode 230c and the third interlayer 220c.

[0090] The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may be located on the pixel circuit layer PCL. The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may be located on the planarization layer 119. The first lower electrode 210a may be electrically connected to the drain electrode SD1 or the source electrode SD2 of the first transistor TR1 through a contact hole penetrating the planarization layer 119. The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may be spaced apart from each other in a first direction (e.g., x direction).

[0091] The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may be (semi) transmissive electrodes or reflective electrodes. The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may each include a reflective layer including Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a compound thereof, and a transparent or semi-transparent electrode layer formed on the reflective layer. The transparent or semi-transparent electrode layer may include indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide (In 2 O 3 ), at least one of indium gallium oxide (IGO), and aluminum zinc oxide (AZO). According to some embodiments, each of the first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may include ITO / Ag / ITO.

[0092] The display device 1 may further include a pixel defining layer 120 located on the pixel circuit layer PCL. The pixel defining layer 120 may cover the edges of the first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c. The pixel defining layer 120 may directly contact the upper surface and the side surface of the first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c.

[0093] According to some embodiments, the pixel defining layer 120 may include an organic material such as acrylic acid, benzocyclobutene (BCB) or hexamethyldisiloxane (HMDSO). According to some embodiments, the pixel defining layer 120 may include a photoresist, i.e., a photosensitive resin. For example, a negative photoresist in which a cross-linking reaction is induced during exposure is included.

[0094] The pixel defining layer 120 may define a first opening 120OP1 exposing a central portion of the first lower electrode 210a, a second opening 120OP2 exposing a central portion of the second lower electrode 210b, and a third opening 120OP3 exposing a central portion of the third lower electrode 210c. By increasing the distance between the first to third lower electrodes 210a, 210b, 210c and the upper electrode 230, arcing at the edges of the first to third lower electrodes 210a, 210b, and 210c is prevented or reduced.

[0095] The first emission layer 220a may be arranged in the first opening 120OP1 of the pixel defining layer 120. The first emission layer 220a may be located on the first-1 functional layer 215a described in detail below. The second emission layer 220b may be arranged in the second opening 120OP2 of the pixel defining layer 120. The second emission layer 220b may be located on the first-2 functional layer 215b described below. The third emission layer 220c may be arranged in the third opening 120OP3 of the pixel defining layer 120. The third emission layer 220c may be located on the first-3 functional layer 215c described below.

[0096] The level of the upper surface 220au of the first emission layer 220a may be higher at the edge portion of the first emission layer 220a than at the center portion of the first emission layer 220a. Similarly, the level of the upper surface 220bu of the second emission layer 220b may be higher at the edge portion of the second emission layer 220b than at the center portion of the second emission layer 220b. In contrast, the upper surface 220cu of the third emission layer 220c may be substantially flat. Therefore, the level of the upper surface 220cu of the third emission layer 220c may be substantially the same at the center portion of the third emission layer 220c and at the edge portion of the third emission layer 220c.

[0097] The first emission layer 220a and the second emission layer 220b may be formed by an inkjet printing process, and the third emission layer 220c may be formed by a vapor deposition process. For example, the vapor deposition process may include physical vapor deposition (PVD), chemical vapor deposition (CVD), sputtering, or thermal evaporation. The first emission layer 220a and the second emission layer 220b are formed in the same process and thus may have similar shapes. For example, Figure 5 As shown in , the level of each of the upper surface 220au of the first emission layer 220a and the upper surface 220bu of the second emission layer 220b may be lower at the center portion thereof than at the edge portion thereof, thereby forming a concave shape. In contrast, the third emission layer 220c is formed in a process different from that of the first emission layer 220a and the second emission layer 220b, and thus may have a shape different from that of the first emission layer 220a and the second emission layer 220b. For example, as Figure 5As shown in FIG. 2 , unlike the upper surface 220au of the first emission layer 220a and the upper surface 220bu of the second emission layer 220b, the upper surface 220cu of the third emission layer 220c may be flat (or substantially flat).

[0098] Herein, “the level of ‘A’ is higher than the level of ‘B’” means that the distance between the upper end of A and the upper surface of the substrate 100 is greater than the distance between the upper end of B and the upper surface of the substrate 100. For example, the distance between the upper surface 220au of the first emission layer 220a and the upper surface of the substrate 100 may be greater at the edge portion of the first emission layer 220a than at the center portion of the first emission layer 220a. That is, the level of the upper surface 220au of the first emission layer 220a may be higher at the edge portion of the first emission layer 220a than at the center portion of the first emission layer 220a.

[0099] Herein, the central portion of the emission layer and the functional layer may be the center of the opening of the pixel defining layer 120 , and the edge portions of the emission layer and the functional layer may be arranged outside the central portion and adjacent to the inner wall of the pixel defining layer defining the opening of the pixel defining layer.

[0100] According to some embodiments, the first emission layer 220a and the second emission layer 220b may include an inorganic emission material. For example, the first emission layer 220a and the second emission layer 220b may include quantum dots. According to some embodiments, the first emission layer 220a and the second emission layer 220b including quantum dots may be referred to as the first quantum dot emission layer and the second quantum dot emission layer, respectively. The quantum dots included in the first emission layer 220a and the second emission layer 220b may act as dopants, and the first emission layer 220a and the second emission layer 220b may further include a host and / or a delayed fluorescent material. Quantum dots refer to crystals of semiconductor compounds. Quantum dots can emit light of various emission wavelengths depending on the size of the crystal. By controlling the element ratio of the quantum dots, the quantum dots can emit light of various emission wavelengths. For example, the diameter of the quantum dots may be about 1nm to about 10nm.

[0101] Quantum dots can be synthesized by wet chemical process, metal organic chemical vapor deposition (MOCVD) process, molecular beam epitaxy (MBE) process or other similar processes. Wet chemical process is a method of growing quantum dot particle crystals after mixing organic solvents and precursor materials. When quantum dot particle crystals grow, because organic solvents naturally act as dispersants coordinated on the surface of quantum dot particle crystals and control the growth of quantum dot particle crystals, it is easier and more cost-effective to control the growth of quantum dot particle crystals than using MOCVD or MBE vapor deposition methods.

[0102] The quantum dots may include Group II-VI semiconductor compounds; Group III-V semiconductor compounds; Group III-VI semiconductor compounds; Group I-III-VI semiconductor compounds; Group IV-VI semiconductor compounds; Group IV elements or compounds; or any combination thereof.

[0103] Examples of Group II-VI semiconductor compounds are binary compounds such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe and MgS; ternary compounds such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe and MgZnS; quaternary compounds such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe; or any combination thereof.

[0104] Examples of Group III-V semiconductor compounds are binary compounds such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, and InSb; ternary compounds such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, and InPSb; quaternary compounds such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, and InAlPSb; or any combination thereof. The Group III-V semiconductor compounds may further include Group II elements. Examples of the Group III-V semiconductor compound further including the Group II element are InZnP, InGaZnP, InAlZnP, and the like.

[0105] Examples of III-VI semiconductor compounds are binary compounds such as GaS, Ga 2 S 3 ,GaSe,Ga 2 Se 3 、GaTe、InS、InSe、In 2 S3 、In 2 Se 3 and InTe; ternary compounds such as InGaS 3 and InGaSe 3 ; or any combination thereof.

[0106] Examples of Group I-III-VI semiconductor compounds are ternary compounds such as AgInS, AgInS 2 、AgInSe 2 、AgGaS、AgGaS 2 、AgGaSe 2 、CuInS、CuInS 2 、CuInSe 2 、CuGaS 2 、CuGaSe 2 、CuGaO 2 、AgGaO 2 and AgAlO 2 ; Quaternary compounds such as AgInGaS 2 、AgInGaSe 2 and CuInGaS; or any combination thereof.

[0107] Examples of Group IV-VI semiconductor compounds are binary compounds such as SnS, SnSe, SnTe, PbS, PbSe and PbTe; ternary compounds such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe and SnPbTe; quaternary compounds such as SnPbSSe, SnPbSeTe and SnPbSTe; or any combination thereof.

[0108] The Group IV elements or compounds may include single elements such as Si and Ge; binary compounds such as SiC and SiGe; or any combination thereof.

[0109] Elements included in a multinary compound (such as a binary compound, a ternary compound, and a quaternary compound) may be present in the particles at a uniform concentration or a non-uniform concentration. In other words, the chemical formula represents the type of elements included in the compound, and the element ratios of the compound may be different. For example, AgInGaS 2 Can represent AgIn x Ga 1-x S 2 (0 <x<1)。

[0110] The quantum dot may have a single structure or a core-shell dual structure, in which each element included in the quantum dot has a uniform concentration. For example, the material included in the core and the material included in the shell may be different from each other. The shell may cover at least a portion of the core.

[0111] The core may include Cd, Zn, Hg, Mg, Ga, Al, In, Sn, Pb, Se, Te, P or Sb.

[0112] The shell of the quantum dot can act as a protective layer to prevent or reduce the chemical denaturation of the core to maintain semiconductor properties, and / or can act as a charging layer to give the quantum dot electrophoretic properties. The shell can be a single layer or multiple layers. The interface between the core and the shell can have a concentration gradient in which the concentration of the element of the shell decreases toward the core.

[0113] Examples of quantum dot shells are metal oxides or non-metal oxides, semiconductor compounds, or any combination thereof. Examples of metal oxides or non-metal oxides are binary compounds such as SiO x 、Al 2 O 3 、TiO 2 、ZnO、MnO、Mn 2 O 3 , Mn 3 O 4 , CuO, FeO, Fe 2 O 3 , Fe 3 O 4 , CoO, Co 3 O 4 and NiO, ternary compounds such as MgAl 2 O 4 、CoFe 2 O 4 、NiFe 2 O 4 and CoMn 2 O 4 etc., or any combination thereof. Examples of semiconductor compounds are II-VI semiconductor compounds, III-V semiconductor compounds, III-VI semiconductor compounds, I-III-VI semiconductor compounds, IV-VI semiconductor compounds, or any combination thereof. For example, the semiconductor compound may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaS, GaSe, AgGaS, AgGaS 2 , GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb or any combination thereof.

[0114] The elements included in the multi-element compound (such as the binary compound and the ternary compound) may exist in the particle at a uniform concentration or at a non-uniform concentration. In other words, the chemical formula represents the type of elements included in the compound, and the element ratio of the compound may be different.

[0115] The quantum dots may have a full width at half maximum (FWHM) of about 45 nm or less, particularly about 40 nm or less, or particularly about 30 nm or less, and may improve color purity or color reproducibility within the above range. In addition, since the light emitted by the quantum dots is emitted in all directions, the light viewing angle may be improved.

[0116] In addition, the shape of the quantum dot may be spherical, pyramidal, multi-armed or cubic, and the quantum dot may be a nanoparticle, a nanotube, a nanowire, a nanofiber or a nanoplate, etc.

[0117] Because the energy band gap can be adjusted by controlling the size of the quantum dots or controlling the ratio of elements in the quantum dot compound, light of various wavelengths can be obtained from the quantum dot emission layer. Therefore, by using the above-mentioned quantum dots (quantum dots of different sizes or quantum dots with different ratios of elements in the quantum dot compound), a light-emitting diode that emits light of various wavelengths can be realized. For example, the size of the quantum dots or the ratio of elements in the quantum dot compound is controlled, and as a result, light selected from red light, green light and / or blue light can be emitted. In addition, the quantum dots can be configured to emit white light by a combination of light of various colors.

[0118] According to some embodiments, the third emission layer 220c may include an organic emission material. For example, the third emission layer 220c may not include quantum dots, and may include only organic emission materials. According to some embodiments, the third emission layer 220c including an organic emission material may be referred to as an organic emission layer. For example, the third emission layer 220c may include an organic emission material including a fluorescent or phosphorescent material that emits red light, green light, blue light, or white light. The above-mentioned third emission layer 220c may include an organic emission layer including a low molecular weight organic emission material or a high molecular weight organic emission material. For example, the third emission layer 220c as an organic emission layer may include copper phthalocyanine, tris (8-hydroxyquinoline) aluminum, PPV (polystyrene) type material, or polyfluorene type material.

[0119] The first-1 functional layer 215a may be arranged in the first opening 120OP1 of the pixel defining layer 120. The first-1 functional layer 215a may be located on the first lower electrode 210a. The first-2 functional layer 215b may be arranged in the second opening 120OP2 of the pixel defining layer 120. The first-2 functional layer 215b may be located on the second lower electrode 210b. The first-3 functional layer 215c may be arranged in the third opening 120OP3 of the pixel defining layer 120. The first-3 functional layer 215c may be located on the third lower electrode 210c.

[0120] The level of the upper surface 215au of the first-1 functional layer 215a may be higher at the edge portion of the first-1 functional layer 215a than at the center portion of the first-1 functional layer 215a. Similarly, the level of the upper surface 215bu of the first-2 functional layer 215b may be higher at the edge portion of the first-2 functional layer 215b than at the center portion of the first-2 functional layer 215b. In contrast, the upper surface 215cu of the first-3 functional layer 215c may be substantially flat. Therefore, the level of the upper surface 215cu of the first-3 functional layer 215c may be substantially the same at the center portion of the first-3 functional layer 215c and at the edge portion of the first-3 functional layer 215c.

[0121] The first-1 functional layer 215a and the first-2 functional layer 215b may be formed by an inkjet printing process, and the first-3 functional layer 215c may be formed by a vapor deposition process. The first-1 functional layer 215a and the first-2 functional layer 215b are formed in the same process and thus may have similar shapes. For example, Figure 5 As shown in , the level of each of the upper surface 215au of the first-1 functional layer 215a and the upper surface 215bu of the first-2 functional layer 215b may be lower at the center portion thereof than at the edge portion thereof, thereby forming a concave shape. In contrast, since the first-3 functional layer 215c is formed in a process different from that of the first-1 functional layer 215a and the first-2 functional layer 215b, the first-3 functional layer 215c may have a shape different from that of the first-1 functional layer 215a and the first-2 functional layer 215b. For example, as Figure 5 As shown in FIG. 1 , unlike the upper surface 215au of the 1st-1 functional layer 215a and the upper surface 215bu of the 1st-2 functional layer 215b , the upper surface 215cu of the 1st-3 functional layer 215c may be substantially flat.

[0122] The second-1 functional layer 225a may be arranged in the first opening 120OP1 of the pixel defining layer 120. The second-1 functional layer 225a may be located on the first emission layer 220a. The second-2 functional layer 225b may be arranged in the second opening 120OP2 of the pixel defining layer 120. The second-2 functional layer 215b may be located on the second emission layer 220b. The second-3 functional layer 225c may be arranged in the third opening 120OP3 of the pixel defining layer 120. The second-3 functional layer 225c may be located on the third emission layer 220c.

[0123] The second-1 functional layer 225a, the second-2 functional layer 225b, and the second-3 functional layer 225c may be formed by a vapor deposition process. Since the upper surface 225au of the second-1 functional layer 225a, the upper surface 225bu of the second-2 functional layer 225b, and the upper surface 225cu of the second-3 functional layer 225c are formed in the same process, their shapes may be substantially similar. For example, the upper surface 225au of the second-1 functional layer 225a, the upper surface 225bu of the second-2 functional layer 225b, and the upper surface 225cu of the second-3 functional layer 225c may be substantially flat.

[0124] According to some embodiments, the first-1 functional layer 215a, the first-2 functional layer 215b, and the first-3 functional layer 215c may have the same function, and the second-1 functional layer 225a, the second-2 functional layer 225b, and the second-3 functional layer 225c may have the same function. For example, the first-1 functional layer 215a, the first-2 functional layer 215b, and the first-3 functional layer 215c may each be a hole transport region, and the second-1 functional layer 225a, the second-2 functional layer 225b, and the second-3 functional layer 225c may each be an electron transport region. As another example, the first-1 functional layer 215a, the first-2 functional layer 215b, and the first-3 functional layer 215c may each be an electron transport region, and the second-1 functional layer 225a, the second-2 functional layer 225b, and the second-3 functional layer 225c may each be a hole transport region.

[0125] According to some embodiments, the first-1 functional layer 215a included in the first light emitting diode LED1 as a quantum dot light emitting diode and the first-2 functional layer 215b included in the second light emitting diode LED2 as a quantum dot light emitting diode may have a function different from that of the first-3 functional layer 215c included in the third light emitting diode LED3 as an organic light emitting diode. In this case, the second-1 functional layer 225a included in the first light emitting diode LED1 as a quantum dot light emitting diode and the second-2 functional layer 225b included in the second light emitting diode LED2 as a quantum dot light emitting diode may have a function different from that of the second-3 functional layer 225c included in the third light emitting diode LED3 as an organic light emitting diode. For example, the first-1 functional layer 215a and the first-2 functional layer 215b may be a hole transport region, and the first-3 functional layer 215c may be an electron transport region. In this case, the second-1 functional layer 225a and the second-2 functional layer 225b may be an electron transport region, and the second-3 functional layer 225c may be a hole transport region. In another example, the first-1 functional layer 215a and the first-2 functional layer 215b may be electron transport regions, and the first-3 functional layer 215c may be a hole transport region. In this case, the second-1 functional layer 225a and the second-2 functional layer 225b may be hole transport regions, and the second-3 functional layer 225c may be an electron transport region.

[0126] The electron transport region may include at least an electron transport layer (ETL), and further include an electron injection layer, a hole blocking layer, or any combination thereof. The hole transport region may include at least a hole transport layer (HTL), and further include a hole injection layer, an electron blocking layer, or any combination thereof.

[0127] According to some embodiments, the first-1 functional layer 215a and the second-1 functional layer 225a included in the first light-emitting diode LED1 as a quantum dot light-emitting diode may be inorganic functional layers including inorganic materials. According to some embodiments, the first-2 functional layer 215b and the second-2 functional layer 225b included in the second light-emitting diode LED2 as a quantum dot light-emitting diode may be inorganic functional layers including inorganic materials. The first-1 functional layer 215a and the first-2 functional layer 215b may be referred to as a first inorganic functional layer, and the second-1 functional layer 225a and the second-2 functional layer 225b may be referred to as a second inorganic functional layer.

[0128] The inorganic functional layer may include an inorganic HTL or an inorganic ETL. For example, when the first-1 functional layer 215a and the first-2 functional layer 215b include an inorganic HTL, the second-1 functional layer 225a and the second-2 functional layer 225b may include an inorganic ETL. In another example, when the first-1 functional layer 215a and the first-2 functional layer 215b include an inorganic ETL, the second-1 functional layer 225a and the second-2 functional layer 225b may include an inorganic HTL.

[0129] The inorganic HTL may include an inorganic oxide. For example, the inorganic HTL may include molybdenum oxide (MoO x ), vanadium oxide (V 2 O 5 ), hydrogen molybdenum bronze (H x MoO 3 ) and hydrogen vanadium bronze (H x V 2 O 5 ). According to some embodiments, the inorganic HTL may include an inorganic oxide and an organic material. For example, the inorganic HTL may include an inorganic oxide and further include an organic compound such as tetrakis([1,1'-biphenyl]-4-yl)-[1,1':4',1"-terphenyl]-4,4"-diamine (TaTm), 4,4'-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline (TAPC) or 1,3-bis(N-carbazolyl)benzene (mCP)).

[0130] The inorganic ETL may include at least an inorganic oxide. For example, the inorganic ETL may include an inorganic oxide including TiO 2 , ZnO, zinc magnesium oxide (ZnMgO) and tin oxide (SnO x ). According to some embodiments, the inorganic ETL may further include Cs, Al, or any combination thereof. According to some embodiments, the inorganic ETL may further include an organic material. For example, the inorganic ETL may include an inorganic oxide and a nitrogen-containing organic compound. For example, the inorganic ETL may include an inorganic oxide and an organic compound (such as diphenyl-bis[4-(pyridin-3-yl)phenyl]silane (DPPS), 1,3,5-tris[(3-pyridinyl)-3-phenyl]benzene (TmPyPB), or bis(4,6-difluorophenylpyridine-N,C2)picolinyliridium (FIrpic)).

[0131] According to some embodiments, the first-3 functional layer 215c and the second-3 functional layer 225c included in the third light emitting diode LED3 as an organic light emitting diode may be organic functional layers including organic materials. The first-3 functional layer 215c may be referred to as a first organic functional layer, and the second-3 functional layer 225c may be referred to as a second organic functional layer. The organic functional layer may include an organic HTL or an organic ETL. For example, when the first-3 functional layer 215c includes an organic HTL, the second-3 functional layer 225c may include an organic ETL. For example, when the first-3 functional layer 215c includes an organic ETL, the second-3 functional layer 225c may include an organic HTL.

[0132] The organic HTL may include organic materials. For example, the organic HTL may include carbazole derivatives (such as N-phenylcarbazole, polyvinylcarbazole, etc.), fluorene derivatives (such as poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine)] (TFB)), or triphenylamine derivatives (such as N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4,4',4"-tri(carbazol-9-yl)triphenylamine (TCTA), poly(fluoro-co-triphenylamine) (PFO-TPA), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1-biphenyl]-4,4'-diaminobenzene-cyclobutene (TPD-BCB), 1,3,5-tri(3-carbazyl)benzene (TCZ) II), polystyrene-N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine-trifluorovinyl ether (PS-TPD-TFV), tris(trifluorovinyl ether)-4,4',4"-tris(carbazol-9-yl)triphenylamine (Tri-TFV-TCTA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), 4,4'-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline] (TAPC) or 4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl) (HMTPD)), etc.

[0133] The organic ETL may include an organic material. For example, the organic ETL may include tris(8-hydroxyquinoline)aluminum (Alq 3), 1,3,5-tris[(3-pyridyl)-phenyl-3-yl]benzene, 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazol-1-yl)phenyl)-9,10-dinaphthylanthracene, 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl 1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalene-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole ( t Bu-PBD), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-hydroxy)aluminum (BAlq), bis(benzoquinoline-10-hydroxy)beryllium (Bebq 2 ), 9,10-di(naphthalene-2-yl)anthracene (ADN), 9,9-di(4,4'-bis(3,6-di-tert-butylcarbazole)-phenyl)-9H-fluorene (TBCPF), bis(4-(N,N-diphenylamino)phenyl)benzene (BA), 2,7-bis(diphenylphosphoryl)-9,9-spirobifluorene (SPPO13), 9-(3-(9H-carbazole-9-yl)phenyl)-3-(diphenylphosphoryl)-9H-carbazole (mCPPO1), m-phenyl-oxadiazole-triphenylbenzimidazole (m-PhOTPBi), poly[9,9-bis(6'-(diethanolamino)hexyl)-fluorene] (PFN-OH) or a mixture thereof, but the embodiment is not limited thereto.

[0134] The upper electrode 230 may include a first upper electrode 230a of the first light emitting diode LED1, a second upper electrode 230b of the second light emitting diode LED2, and a third upper electrode 230c of the third light emitting diode LED3. The first upper electrode 230a, the second upper electrode 230b, and the third upper electrode 230c may be integrally provided as a single upper electrode 230. The upper electrode 230 may be integrally provided across the entire surface of the substrate 100 to cover the second-1 functional layer 225a, the second-2 functional layer 225b, and the second-3 functional layer 225c.

[0135] The upper electrode 230 may include a metal, an alloy, an electrically conductive compound, or any combination thereof having a low work function. The upper electrode 230 may include, for example, lithium (Li), Ag, Mg, Al, aluminum lithium (Al-Li), Ca, magnesium indium (Mg-In), magnesium silver (Mg-Ag), ytterbium (Yb), silver ytterbium (Ag-Yb), ITO, IZO, or any combination thereof. The upper electrode 230 may be a transmissive electrode, a transflective electrode, or a reflective electrode. The upper electrode 230 may have a single-layer structure including a single layer or a multilayer structure including a plurality of layers.

[0136] The display device 1 may have a structure including both a quantum dot light emitting diode and an organic light emitting diode. The quantum dot light emitting diode has a low material cost and excellent color coordinates. Compared with the life of the quantum dot light emitting diode, the organic light emitting diode has a longer life. Because the first light emitting diode LED1 and the second light emitting diode LED2 of the display device 1 according to some embodiments use quantum dot light emitting diodes, and the third light emitting diode LED3 of the display device 1 according to some embodiments uses an organic light emitting diode, the color purity and color reproducibility are improved, thereby achieving excellent light emitting characteristics and a long life. The present disclosure is not limited to the first light emitting diode LED1 and the second light emitting diode LED2 including quantum dot light emitting diodes and the third light emitting diode LED3 including an organic light emitting diode. Therefore, the first light emitting diode LED1 or the second light emitting diode LED2 may include an organic light emitting diode, and the third light emitting diode LED3 may include a quantum dot light emitting diode.

[0137] According to some embodiments, the thin film encapsulation layer TFE may be located on the first light emitting diode LED1, the second light emitting diode LED2, and the third light emitting diode LED3. The thin film encapsulation layer TFE may include at least one inorganic encapsulation layer and at least one organic encapsulation layer. According to some embodiments, as Figure 5 As shown in , the thin film encapsulation layer TFE may include a first inorganic encapsulation layer 510 on the display element layer DEL, an organic encapsulation layer 520 on the first inorganic encapsulation layer 510 , and a second inorganic encapsulation layer 530 on the organic encapsulation layer 520 .

[0138] The first inorganic encapsulation layer 510 and the second inorganic encapsulation layer 530 may include, for example, an inorganic insulating material such as Al 2 O 3 、TiO 2 、 2 O 5 , HfO 2 、ZnO x 、SiO x 、SiN xOr SiON. The organic encapsulation layer 520 may include, for example, a polymer-based material. Examples of the polymer-based material may include acrylic resin, epoxy resin, polyimide, or polyethylene. According to some embodiments, the organic encapsulation layer 520 may include acrylate.

[0139] Figure 5 It is explained that the light emitting diode is sealed by the thin film encapsulation layer TFE, but the embodiment is not limited thereto, and as Figure 3B As explained in , according to some embodiments, the light emitting diode may be sealed by the sealing member 300 and the sealing substrate 400 .

[0140] Figures 6 to 13 Each is a schematic cross-sectional view of a manufacturing process of a display device according to some embodiments. Figures 6 to 13 For each manufacturing step of the display device along Figure 4 A cross-sectional view of the display device taken along line II'.

[0141] refer to Figure 6 , a pixel circuit layer PCL is formed on the substrate 100 , and a first lower electrode 210 a , a second lower electrode 210 b , and a third lower electrode 210 c may be formed on the pixel circuit layer PCL.

[0142] The pixel circuit layer PCL may include a first transistor TR1, a second transistor TR2, and a third transistor TR3. The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may be spaced apart from each other on the planarization layer 119. The first lower electrode 210a may correspond to the first pixel PX1 ( Figure 4 ), the second lower electrode 210b may correspond to the second pixel PX2 ( Figure 4 ), and the third lower electrode 210c may correspond to the third pixel PX3 ( Figure 4 ). The first lower electrode 210a may be electrically connected to the first transistor TR1, the second lower electrode 210b may be electrically connected to the second transistor TR2, and the third lower electrode 210c may be electrically connected to the third transistor TR3.

[0143] The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may be (semi) transmissive electrodes or reflective electrodes. The first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may each include a reflective layer and a transparent or semi-transparent electrode layer formed on the reflective layer, and the reflective layer includes Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a compound thereof. The transparent or semi-transparent electrode layer may include a material selected from indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide (In 2 O 3), at least one of indium gallium oxide (IGO), and aluminum zinc oxide (AZO). According to some embodiments, each of the first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c may include ITO / Ag / ITO.

[0144] Next, a pixel defining layer 120 may be formed on the pixel circuit layer PCL. The pixel defining layer 120 may cover edges of the first lower electrode 210a, the second lower electrode 210b, and the third lower electrode 210c, and may include a first opening 120OP1 exposing a central portion of the first lower electrode 210a, a second opening 120OP2 exposing a central portion of the second lower electrode 210b, and a third opening 120OP3 exposing a central portion of the third lower electrode 210c.

[0145] Next, refer to Figure 7 The first-1 functional layer 215a and the first-2 functional layer 215b may be respectively located on the first lower electrode 210a and the second lower electrode 210b. The first-1 functional layer 215a may be formed in the first opening 120OP1 of the pixel defining layer 120, and the first-2 functional layer 215b may be formed in the second opening 120OP2 of the pixel defining layer 120.

[0146] The first-1 functional layer 215a and the first-2 functional layer 215b may be formed by an inkjet printing process. Since the first-1 functional layer 215a and the first-2 functional layer 215b are formed by an inkjet printing process, due to the difference in evaporation speed of the liquid included in each functional layer, the liquid may flow to the edge, resulting in the upper surface 215au of the first-1 functional layer 215a and the upper surface 215bu of the first-2 functional layer 215b being concave at their central portions. That is, the level of the upper surface 215au of the first-1 functional layer 215a may be higher at the edge portion of the first-1 functional layer 215a than at the central portion of the first-1 functional layer 215a. Similarly, the level of the upper surface 215bu of the first-2 functional layer 215b may be higher at the edge portion of the first-2 functional layer 215b than at the central portion of the first-2 functional layer 215b.

[0147] The first-1 functional layer 215 a and the first-2 functional layer 215 b may include an inorganic material.

[0148] For example, when the first-1 functional layer 215a and the first-2 functional layer 215b include an inorganic HTL, the first-1 functional layer 215a and the first-2 functional layer 215b may include MoO x 、V 2 O 5 , H x MoO 3 and H x V2 O 5 At least one of .

[0149] For example, when the first-1 functional layer 215a and the first-2 functional layer 215b include an inorganic ETL, the first-1 functional layer 215a and the first-2 functional layer 215b may include an inorganic oxide including TiO 2 , ZnO, ZnMgO and SnO x According to some embodiments, when the first-1 functional layer 215a and the first-2 functional layer 215b include the inorganic ETL, the first-1 functional layer 215a and the first-2 functional layer 215b may further include Cs, Al, or any combination thereof.

[0150] Next, refer to Figure 8 The first emission layer 220a and the second emission layer 220b may be respectively located on the first-1 functional layer 215a and the first-2 functional layer 215b. The first emission layer 220a may be formed in the first opening 120OP1 of the pixel defining layer 120, and the second emission layer 220b may be formed in the second opening 120OP2 of the pixel defining layer 120.

[0151] The first emission layer 220a and the second emission layer 220b may be formed by an inkjet printing process. Because the first emission layer 220a and the second emission layer 220b are formed by an inkjet printing process, due to the difference in evaporation speed of the liquid included in each functional layer, the liquid may flow to the edge, resulting in the upper surface 220au of the first emission layer 220a and the upper surface 220bu of the second emission layer 220b being concave at their central portions. That is, the level of the upper surface 220au of the first emission layer 220a may be higher at the edge portion of the first emission layer 220a than at the central portion of the first emission layer 220a. Similarly, the level of the upper surface 220bu of the second emission layer 220b may be higher at the edge portion of the second emission layer 220b than at the central portion of the second emission layer 220b.

[0152] The first emission layer 220a and the second emission layer 220b may include an inorganic emission material. For example, the first emission layer 220a and the second emission layer 220b may include quantum dots. According to some embodiments, the first emission layer 220a and the second emission layer 220b including quantum dots may be referred to as a first quantum dot emission layer and a second quantum dot emission layer, respectively. The quantum dots included in the first emission layer 220a and the second emission layer 220b may act as dopants, and the first emission layer 220a and the second emission layer 220b may further include a host and / or a delayed fluorescent material.

[0153] After forming the first emission layer 220a and the second emission layer 220b as quantum dot emission layers by an inkjet printing process, the structure in which the pixel circuit layer PCL, the pixel defining layer 120, the first-1 functional layer 215a, the first-2 functional layer 215b, the first emission layer 220a and the second emission layer 220b are formed on the substrate 100 can be moved to a deposition device.

[0154] Next, refer to Fig. 9 The second-1 functional layer 225a and the second-2 functional layer 225b may be respectively located on the first emission layer 220a and the second emission layer 220b. The second-1 functional layer 225a may be formed in the first opening 120OP1 of the pixel defining layer 120, and the second-2 functional layer 225b may be formed in the second opening 120OP2 of the pixel defining layer 120.

[0155] The second-1 functional layer 225 a and the second-2 functional layer 225 b may include an inorganic material.

[0156] For example, when the first-1 functional layer 215a and the first-2 functional layer 215b include an inorganic HTL, the second-1 functional layer 225a and the second-2 functional layer 225b may include an inorganic ETL. For example, when the first-1 functional layer 215a and the first-2 functional layer 215b include MoO x 、V 2 O 5 , H x MoO 3 and H x V 2 O 5 When at least one of the second-1 functional layer 225a and the second-2 functional layer 225b is present, the second-1 functional layer 225a and the second-2 functional layer 225b may include an inorganic oxide, the inorganic oxide including TiO 2 , ZnO, ZnMgO and SnO x At least one of. According to some embodiments, when the second-1 functional layer 225a and the second-2 functional layer 225b include an inorganic ETL, the second-1 functional layer 225a and the second-2 functional layer 225b may further include Cs, Al, or any combination thereof. According to some embodiments, when the second-1 functional layer 225a and the second-2 functional layer 225b include an inorganic ETL, the second-1 functional layer 225a and the second-2 functional layer 225b may further include an organic compound, such as diphenyl-bis[4-(pyridin-3-yl)phenyl]silane (DPPS), 1,3,5-tris(meta-pyridin-3-yl-phenyl)benzene (TmPyPB), or bis(4,6-difluorophenylpyridine-N,C2)picolinyliridium (FIrpic). The organic compound included in the second-1 functional layer 225a and the second-2 functional layer 225b may be deposited with the inorganic oxide by co-evaporation.

[0157] According to some embodiments, when the first-1 functional layer 215a and the first-2 functional layer 215b include an inorganic ETL, the second-1 functional layer 225a and the second-2 functional layer 225b may include an inorganic HTL. For example, when the first-1 functional layer 215a and the first-2 functional layer 215b include TiO 2 , ZnO, ZnMgO and SnO x When at least one inorganic oxide is used, the second-1 functional layer 225a and the second-2 functional layer 225b may include MoO x 、V 2 O 5 , H x MoO 3 and H x V 2 O 5 According to some embodiments, when the second-1 functional layer 225a and the second-2 functional layer 225b include an inorganic HTL, the inorganic HTL may include an inorganic oxide, and further include an organic compound such as tetrakis([1,1'-biphenyl]-4-yl)-[1,1':4',1"-terphenyl]-4,4"-diamine (TaTm), 4,4'-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline (TAPC) or 1,3-bis(N-carbazolyl)benzene (mCP). The organic compound included in the second-1 functional layer 225a and the second-2 functional layer 225b may be deposited with the inorganic oxide by co-evaporation.

[0158] The second-1 functional layer 225a and the second-2 functional layer 225b may be formed by a vapor deposition process. Unlike the present disclosure, when the second-1 functional layer 225a and the second-2 functional layer 225b are formed by an inkjet printing process, due to the mutual mixing of the first emission layer 220a and the second emission layer 220b with the inorganic oxide included in the second-1 functional layer 225a and the second-2 functional layer 225b, the inflow of quantum dots included in the first emission layer 220a and the second emission layer 220b into the second-1 functional layer 225a and the second-2 functional layer 225a may be increased. When the mutual mixing between the functional layer and the emission layer increases, the efficiency and life of the light emitting diode may be reduced. In an embodiment of the present disclosure, since the second-1 functional layer 225a and the second-2 functional layer 225b are formed by a vapor deposition process, the mutual mixing between the functional layers and the emission layers is reduced, thereby improving the stability of the interface between the second-1 functional layer 225a and the first emission layer 220a and between the second-2 functional layer 225b and the second emission layer 220b.

[0159] Because the second-1 functional layer 225a and the second-2 functional layer 225b are formed through a vapor deposition process, an upper surface 225au of the second-1 functional layer 225a and an upper surface 225bu of the second-2 functional layer 225b may be substantially flat.

[0160] Next, refer to Fig.10 The first-3 functional layer 215 c may be formed on the third lower electrode 210 c. The first-3 functional layer 215 c may be disposed in the third opening 120OP3 of the pixel defining layer 120 .

[0161] The first-3 functional layer 215c may be formed by a vapor deposition process. Because the first-3 functional layer 215c is formed by a vapor deposition process, unlike the upper surface 215au of the first-1 functional layer 215a and the upper surface 215bu of the first-2 functional layer 215b, the first-3 functional layer 215c may have a substantially flat shape. Therefore, the level of the upper surface 215cu of the first-3 functional layer 215c may be substantially the same at the center portion of the first-3 functional layer 215c and at the edge portion of the first-3 functional layer 215c.

[0162] The 1-3 functional layer 215c may include an organic material.

[0163] For example, when the first-3 functional layer 215c includes an organic HTL, the first-3 functional layer 215c may include a carbazole derivative (such as N-phenylcarbazole and polyvinylcarbazole), a fluorene derivative or a triphenylamine derivative (such as N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4,4',4"-tri(carbazole-9-yl)triphenylamine (TCTA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), 4,4'-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline] (TAPC) and 4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl (HMTPD)), etc.

[0164] For example, when the first-3 functional layer 215c includes an organic ETL, the first-3 functional layer 215c may include tris(8-hydroxyquinoline)aluminum (Alq 3), 1,3,5-tris[(3-pyridyl)-phenyl-3-yl]benzene, 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazol-1-yl)phenyl)-9,10-dinaphthylanthracene, 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl 1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalene-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole ( t Bu-PBD), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-hydroxy)aluminum (BAlq), bis(benzoquinoline-10-hydroxy)beryllium (Bebq 2 ), 9,10-di(naphthalene-2-yl)anthracene (ADN) or a mixture thereof.

[0165] refer to Fig.11 , the third emission layer 220 c may be located on the 1-3 functional layer 225 c . The third emission layer 220 c may be disposed in the third opening 120OP3 of the pixel defining layer 120 .

[0166] The third emission layer 220c may be formed by a vapor deposition process. Because the third emission layer 220c is formed by a vapor deposition process, unlike the upper surface 220au of the first emission layer 220a and the upper surface 220bu of the second emission layer 220b, the third emission layer 220c may have a substantially flat shape. Therefore, the level of the upper surface 220cu of the third emission layer 220c may be substantially the same at the center portion of the third emission layer 220c and at the edge portion of the third emission layer 220c.

[0167] The third emission layer 220c may include an organic emission material. For example, the third emission layer 220c may not include quantum dots, and may include only organic emission materials. According to some embodiments, the third emission layer 220c including an organic emission material may be referred to as an organic emission layer. For example, the third emission layer 220c may include an organic emission material including a fluorescent or phosphorescent material that emits red, green, blue, or white light. The above-mentioned third emission layer 220c may include an organic emission layer including a low molecular weight organic material or a high molecular weight organic emission material. For example, the third emission layer 220c as an organic emission layer may include copper phthalocyanine, tris (8-hydroxyquinoline) aluminum, PPV (polyphenylene vinylene) type material or polyfluorene type material.

[0168] refer to Fig.12 The second-3 functional layer 225 c may be located on the third emission layer 220 c . The second-3 functional layer 225 b may be disposed in the third opening 120OP3 of the pixel defining layer 120 .

[0169] The second-3 functional layer 225c may include an organic material.

[0170] According to some embodiments, when the first-3 functional layer 215 c includes an organic HTL, the second-3 functional layer 225 c may include an organic ETL. For example, when the first-3 functional layer 215c includes a carbazole derivative (such as N-phenylcarbazole and polyvinylcarbazole), a fluorene derivative or a triphenylamine derivative (such as N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4,4',4"-tri(carbazole-9-yl)triphenylamine (TCTA), N,N'-di(1-naphthyl)-N,N'-diphenylbenzidine (NPB), 4,4'-cyclohexylenebis[N,N-bis(4-methylphenyl)aniline] (TAPC) and 4,4'-bis[N,N'-(3-tolyl)amino]-3,3'-dimethylbiphenyl (HMTPD)), etc., the second-3 functional layer 225c may include tris(8-hydroxyquinoline)aluminum (Alq 3 ), 1,3,5-tris[(3-pyridyl)-phenyl-3-yl]benzene, 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine, 2-(4-(N-phenylbenzimidazol-1-yl)phenyl)-9,10-dinaphthylanthracene, 1,3,5-tris(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene (TPBi), 2,9-dimethyl-4,7-diphenyl 1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl-1,2,4-triazole (TAZ), 4-(naphthalene-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole ( t Bu-PBD), bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-hydroxy)aluminum (BAlq), bis(benzoquinoline-10-hydroxy)beryllium (Bebq 2 ), 9,10-di(naphthalene-2-yl)anthracene (ADN) or a mixture thereof.

[0171] In contrast, when the first-3 functional layer 215 c includes the organic ETL, the second-3 functional layer 225 c may include the organic HTL.

[0172] Since the second-3 functional layer 225c is formed through a vapor deposition process, an upper surface 225cu of the second-3 functional layer 225c may be substantially flat.

[0173] refer to Fig.13 The upper electrode 230 may be located on the second-1 functional layer 225a, the second-2 functional layer 225b, and the second-3 functional layer 225c. The upper electrode 230 may be provided integrally across the entire surface of the substrate 100.

[0174] The upper electrode 230 may include a metal, an alloy, an electrically conductive compound, or any combination thereof having a low work function. The upper electrode 230 may include, for example, lithium (Li), Ag, Mg, Al, aluminum lithium (Al-Li), Ca, magnesium indium (Mg-In), magnesium silver (Mg-Ag), ytterbium (Yb), silver ytterbium (Ag-Yb), ITO, IZO, or any combination thereof. The upper electrode 230 may be a transmissive electrode, a transflective electrode, or a reflective electrode. The upper electrode 230 may have a single-layer structure including a single layer or a multilayer structure including a plurality of layers.

[0175] Next, refer to Figure 5 According to some embodiments, a thin film encapsulation layer TFE may be further formed on the upper electrode 230 .

[0176] In the quantum dot light emitting diode of the display device of the present disclosure, for the interface stability between the functional layer and the quantum dot emission layer, the functional layer arranged above and below the quantum dot emission layer can be formed of an inorganic material. In addition, in the organic light emitting diode of the display device of the present disclosure, for the interface stability between the functional layer and the organic emission layer, the functional layer arranged above and below the organic emission layer can be formed of an organic material.

[0177] In the display device of the present disclosure, a first inorganic functional layer and a quantum dot emission layer are sequentially formed by an inkjet printing process, a second inorganic functional layer is formed by a vapor deposition process, and then a first organic functional layer, an organic emission layer, and a second organic functional layer are sequentially formed by a vapor deposition process, thereby preventing or reducing the frequent movement of deposition equipment to improve process efficiency.

[0178] A display device according to some embodiments of the present disclosure may include a light emitting diode including a quantum dot emission layer and a light emitting diode including an organic emission layer, thereby improving light emitting efficiency and lifespan.

[0179] In the display device according to the present disclosure, the emission layer of the light emitting diode including the quantum dot emission layer may be formed by an inkjet printing process, and the inorganic common layer may be formed on the emission layer by a vapor deposition process, thereby improving the reliability of the display device.

[0180] However, the embodiments are only examples and do not limit the scope of the embodiments according to the present disclosure.

[0181] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for limiting purposes. The description of features or aspects within each embodiment should generally be considered to be applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope as defined by the claims and their equivalents.

Claims

1. A display device, comprising: a first light emitting diode and a second light emitting diode, each of which is disposed on a substrate, wherein the first light emitting diode and the second light emitting diode are configured to emit light of different colors from each other, The first light emitting diode comprises: a first lower electrode; A first inorganic functional layer, located on the first lower electrode and comprising an inorganic material; A quantum dot emission layer, located on the first inorganic functional layer and comprising quantum dots; A second inorganic functional layer, located on the quantum dot emission layer and comprising an inorganic material; and a first upper electrode, located on the second inorganic functional layer, The second light emitting diode comprises: a second lower electrode; a first organic functional layer, located on the second lower electrode and comprising an organic material; an organic emission layer, located on the first organic functional layer and comprising an organic material; a second organic functional layer, located on the organic emission layer and comprising an organic material; and A second upper electrode is located on the second organic functional layer, wherein a level of an upper surface of the first inorganic functional layer is higher at an edge portion of the first inorganic functional layer than at a center portion of the first inorganic functional layer, and A level of an upper surface of the first organic functional layer is the same at a center portion of the first organic functional layer and at an edge portion of the first organic functional layer.

2. The display device according to claim 1, wherein the level of the upper surface of the quantum dot emission layer is higher at the edge portion of the quantum dot emission layer than at the center portion of the quantum dot emission layer, and A level of an upper surface of the organic emission layer is the same at a center portion of the organic emission layer and at an edge portion of the organic emission layer.

3. The display device according to claim 1 , wherein a level of an upper surface of the second inorganic functional layer is the same at a central portion of the second inorganic functional layer and at an edge portion of the second inorganic functional layer, and A level of an upper surface of the second organic functional layer is the same at a center portion of the second organic functional layer and at an edge portion of the second organic functional layer.

4. The display device according to claim 1, wherein the first inorganic functional layer includes at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze and hydrogen vanadium bronze, and the second inorganic functional layer includes at least one of titanium oxide, zinc oxide, zinc magnesium oxide and tin oxide.

5. The display device according to claim 1, wherein the first inorganic functional layer includes at least one of titanium oxide, zinc oxide, zinc magnesium oxide and tin oxide, and the second inorganic functional layer includes at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze and hydrogen vanadium bronze.

6. The display device according to claim 1, further comprising a pixel defining layer on the substrate, the pixel defining layer covering an edge of each of the first lower electrode and the second lower electrode and comprising a first opening exposing a central portion of the first lower electrode and a second opening exposing a central portion of the second lower electrode, wherein the first inorganic functional layer, the quantum dot emission layer and the second inorganic functional layer are arranged in the first opening of the pixel defining layer, and The first organic functional layer, the organic emission layer, and the second organic functional layer are arranged in the second opening of the pixel defining layer.

7. A method for manufacturing a display device, the method comprising: forming a first lower electrode and a second lower electrode on a substrate; performing an inkjet printing process on the first lower electrode to form a first inorganic functional layer including an inorganic material; performing an inkjet printing process on the first inorganic functional layer to form a quantum dot emission layer including quantum dots; Performing a vapor deposition process on the quantum dot emission layer to form a second inorganic functional layer; forming a first organic functional layer including an organic material on the second lower electrode; forming an organic emission layer on the first organic functional layer; forming a second organic functional layer including an organic material on the organic emission layer; and An upper electrode is formed on the second inorganic functional layer and the second organic functional layer. The method according to claim 7 , wherein the first organic functional layer is formed by the vapor deposition process.

9. The method according to claim 7, wherein the first inorganic functional layer comprises at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze and hydrogen vanadium bronze, and the second inorganic functional layer comprises at least one of titanium oxide, zinc oxide, zinc magnesium oxide and tin oxide.

10. The method of claim 7, wherein the first inorganic functional layer comprises at least one of titanium oxide, zinc oxide, zinc magnesium oxide, and tin oxide, and the second inorganic functional layer comprises at least one of molybdenum oxide, vanadium oxide, hydrogen molybdenum bronze, and hydrogen vanadium bronze.

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