Display device and method for manufacturing display device

Abstract

According to an embodiment of the invention, a display device and a manufacturing method of the display device are provided. The display device includes a sub-pixel including: a first sub-pixel forming a first sub-pixel region providing light of a first color; a second sub-pixel forming a second sub-pixel region providing light of a second color; and a third sub-pixel forming a third sub-pixel region providing light of a third color. The area of the third sub-pixel region is larger than the area of the first sub-pixel region and the area of the second sub-pixel region. Each of the first sub-pixel and the second sub-pixel includes a quantum dot light emitting element including a quantum dot light emitting layer. The third sub-pixel includes an organic light emitting element including an organic light emitting layer.

Description

Technical Field

[0001] The present disclosure relates to a display device and a method for manufacturing the display device. Background Art

[0002] Recently, as interest in information display increases, research and development of display devices continues.

[0003] The display device as a self-luminous element may include a hole transport portion, an electron transport portion, and a light-emitting diode including a light-emitting layer between the hole transport portion and the electron transport portion. Holes provided from the hole transport portion and electrons provided from the electron transport portion may be recombined in the light-emitting layer to generate excitons. The generated excitons may change from an excited state to a ground state and generate light.

[0004] In addition, the light-emitting layer of the light-emitting element may include an organic light-emitting layer using an organic material and / or a quantum dot light-emitting layer including a quantum dot material. Since the organic light-emitting layer and the quantum dot light-emitting layer include materials having different physical properties from each other, it is somewhat difficult to fully ensure process characteristics while forming a light-emitting structure including both the organic light-emitting layer and the quantum dot light-emitting layer.

[0005] Therefore, it is necessary to prepare a scheme for effectively providing a light emitting structure including an organic light emitting layer and a quantum dot light emitting layer. Summary of the invention

[0006] One aspect of the present disclosure provides a display device capable of efficiently providing a light emitting structure including an organic light emitting layer and a quantum dot light emitting layer, and a method for manufacturing the display device.

[0007] A display device according to an embodiment of the present disclosure may include sub-pixels, the sub-pixels including: a first sub-pixel, forming a first sub-pixel region providing light of a first color; a second sub-pixel, forming a second sub-pixel region providing light of a second color; and a third sub-pixel, forming a third sub-pixel region providing light of a third color. The area of ​​the third sub-pixel region may be greater than the area of ​​the first sub-pixel region and the area of ​​the second sub-pixel region. Each of the first sub-pixel and the second sub-pixel may include a quantum dot light-emitting element including a quantum dot light-emitting layer. The third sub-pixel may include an organic light-emitting element including an organic light-emitting layer.

[0008] According to an embodiment, the area of ​​the second sub-pixel region may be greater than the area of ​​the first sub-pixel region. The first sub-pixel may be a red sub-pixel. The second sub-pixel may be a green sub-pixel. The third sub-pixel may be a blue sub-pixel.

[0009] According to an embodiment, the quantum dot light emitting layer may include a first quantum dot light emitting layer included in the first sub-pixel and a second quantum dot light emitting layer included in the second sub-pixel. The thicknesses of the organic light emitting layer, the first quantum dot light emitting layer and the second quantum dot light emitting layer may be the same.

[0010] According to an embodiment, the display device may further include: a bank surrounding an area where the quantum dot light-emitting layer and the organic light-emitting layer are arranged. The bank may form a first opening portion overlapping the first sub-pixel area, a second opening portion overlapping the second sub-pixel area, and a third opening portion overlapping the third sub-pixel area.

[0011] According to an embodiment, the quantum dot light emitting layer may include a quantum dot compound. The organic light emitting layer may include an organic material.

[0012] According to an embodiment, each of the quantum dot light emitting element and the organic light emitting element may further include a first electrode, a hole transport portion, an electron transport portion, and a second electrode.

[0013] According to an embodiment of the present disclosure, a method for manufacturing a display device may be provided. The display device may include sub-pixels, the sub-pixels including: a first sub-pixel, forming a first sub-pixel region providing light of a first color; a second sub-pixel, forming a second sub-pixel region providing light of a second color; and a third sub-pixel, forming a third sub-pixel region providing light of a third color. The manufacturing method may include the following steps: manufacturing a pixel circuit layer; patterning a levee on the pixel circuit layer; and manufacturing a light-emitting layer in an opening formed by the levee. The opening may include a first opening in the first sub-pixel region, a second opening in the second sub-pixel region, and a third opening in the third sub-pixel region. The step of manufacturing the light-emitting layer may include the following steps: manufacturing an organic light-emitting layer in the third opening; manufacturing a second quantum dot light-emitting layer in the second opening; and manufacturing a first quantum dot light-emitting layer in the first opening. When viewed from a plane, the third opening may have an area larger than that of the first opening and the second opening. The step of manufacturing the organic light-emitting layer may be performed before the step of manufacturing the first quantum dot light-emitting layer and the step of manufacturing the second quantum dot light-emitting layer.

[0014] According to an embodiment, the step of manufacturing the light emitting layer may further include the step of performing an inkjet printing process.

[0015] According to an embodiment, the step of manufacturing the organic light-emitting layer may include the step of jetting an organic light-emitting layer manufacturing ink onto the pixel circuit layer. The step of manufacturing the first quantum dot light-emitting layer may include the step of jetting a first quantum dot ink onto the pixel circuit layer. The step of manufacturing the second quantum dot light-emitting layer may include the step of jetting a second quantum dot ink onto the pixel circuit layer.

[0016] According to an embodiment, the first quantum dot ink and the second quantum dot ink may include the same solvent as each other.

[0017] According to an embodiment, the first quantum dot ink, the second quantum dot ink, and the organic light emitting layer manufacturing ink may include two or more solvents, respectively.

[0018] According to an embodiment, the first quantum dot ink, the second quantum dot ink, and the organic light emitting layer manufacturing ink may include organic solvents, respectively.

[0019] According to an embodiment, the organic light emitting layer manufacturing ink may have a boiling point lower than boiling points of the first quantum dot ink and the second quantum dot ink.

[0020] According to an embodiment, the step of manufacturing the light emitting layer may further include the step of drying the solvents of the first quantum dot ink, the second quantum dot ink and the organic light emitting layer manufacturing ink. The drying step may be performed at a temperature range of 25° C. to 75° C. and in a vacuum environment.

[0021] According to an embodiment, after performing the step of manufacturing the organic light-emitting layer, the step of manufacturing the second quantum dot light-emitting layer may be performed, and after performing the step of manufacturing the second quantum dot light-emitting layer, the step of manufacturing the first quantum dot light-emitting layer may be performed.

[0022] According to an embodiment, each of the first quantum dot light emitting layer and the second quantum dot light emitting layer may include a quantum dot compound. The organic light emitting layer may include an organic material. The organic light emitting layer, the first quantum dot light emitting layer, and the second quantum dot light emitting layer may have the same thickness as each other.

[0023] According to an embodiment of the present disclosure, a display device capable of efficiently providing a light emitting structure including an organic light emitting layer and a quantum dot light emitting layer and a method for manufacturing the display device may be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic plan view showing a display device according to the embodiment.

[0025] Figure 2 is a schematic cross-sectional view showing a display device according to an embodiment.

[0026] Figure 3 is a schematic flowchart illustrating a method for manufacturing a display device according to an embodiment.

[0027] Figure 4 is a schematic flow chart showing steps of manufacturing a light emitting layer according to an embodiment.

[0028] Figures 5 to 10 Schematic cross-sectional views showing the manufacturing method of the display device according to the embodiment in each process step. DETAILED DESCRIPTION

[0029] The present disclosure may be subjected to various changes and various forms, and specific embodiments will be shown in the drawings and described in detail herein. However, this is not intended to limit the present disclosure to a specific disclosed form, and should be understood to include all changes, equivalents and even substitutes included in the concept and technical scope of the present disclosure.

[0030] The terms first, second, etc. can be used when describing a variety of constituent elements, but the constituent elements are not limited to the terms. The terms are only used to distinguish one constituent element from another constituent element. For example, without departing from the scope of the present disclosure, the first constituent element can be named as the second constituent element, and similarly, the second constituent element can also be named as the first constituent element. Unless the context clearly states otherwise, the singular form also includes the plural form.

[0031] In the present disclosure, the terms "including" or "having" should be understood as being used to specify the existence of features, numbers, steps, operations, constituent elements, parts or combinations thereof recorded in the specification, rather than excluding in advance the existence or additional possibility of one or more other features or numbers, steps, operations, constituent elements, parts or combinations thereof. Moreover, when a layer, film, region, plate or other part is mentioned as being "above" another part, it not only includes the case where it is "immediately above" the other part, but also includes the case where other parts exist in the middle. In addition, in the present specification, when a layer, film, region, plate or other part is mentioned as being formed on another part, the direction formed is not limited to the upper direction, but also includes the case where it is formed towards the side or lower direction. On the contrary, when a layer, film, region, plate or other part is mentioned as being "below" another part, this not only includes the case where it is "immediately below" the other part, but also includes the case where other parts exist in the middle.

[0032] The present disclosure relates to a display device and a method for manufacturing the display device. Hereinafter, a display device according to an embodiment will be described with reference to the accompanying drawings.

[0033] Figure 1is a schematic plan view showing a display device according to the embodiment.

[0034] Reference Figure 1 The display device DD may include a base layer BSL and pixels PXL arranged on the base layer BSL. Although not shown, the display device DD may further include a driving circuit portion (eg, a scan driving portion and a data driving portion) for driving the pixels PXL, wirings, and pads.

[0035] The display device DD (or the base layer BSL) may include a display area DA and a non-display area NDA. The non-display area NDA may mean an area outside the display area DA. The non-display area NDA may surround at least a portion of the display area DA.

[0036] The base layer BSL may form a base surface of the display device DD. The base layer BSL may be a rigid or flexible substrate or film, or a flexible substrate or film. For example, the base layer BSL may include a glass material. Alternatively, the base layer BSL may include a silicon material. Alternatively, the base layer BSL may include polyimide. However, the present disclosure is not limited thereto.

[0037] The display area DA may mean an area where the pixels PXL are arranged. The non-display area NDA may mean an area where the pixels PXL are not arranged. A driving circuit part, wirings, and pads connected to the pixels PXL of the display area DA may be arranged in the non-display area NDA.

[0038] According to embodiments, the pixels PXL (or sub-pixels SPX) may be arranged in various structures. For example, the pixels PXL (or sub-pixels SPX) may be arranged in stripes (eg, S-shaped stripes) or PENTILE ® Arrange the structure, etc.

[0039] As an example, Figure 1 The structure in which the pixels PXL (or subpixels SPX) are arranged in an S-strip structure is shown. For example, the third subpixel SPX3 may be adjacent to the first subpixel SPX1 and the second subpixel SPX2 in the first direction DR1, and the first subpixel SPX1 and the second subpixel SPX2 may be adjacent to each other in the second direction DR2.

[0040] According to an embodiment, the pixel PXL (or sub-pixel SPX) may include a first sub-pixel SPX1, a second sub-pixel SPX2, and a third sub-pixel SPX3. Each of the first sub-pixel SPX1, the second sub-pixel SPX2, and the third sub-pixel SPX3 may be a sub-pixel. At least one first sub-pixel SPX1, the second sub-pixel SPX2, and the third sub-pixel SPX3 may form a pixel unit capable of emitting light of multiple colors.

[0041] Each of the first sub-pixel SPX1 , the second sub-pixel SPX2 , and the third sub-pixel SPX3 may emit light of one color.

[0042] For example, the first sub-pixel SPX1 may be a red sub-pixel that emits red (as an example, a first color) light, the second sub-pixel SPX2 may be a green sub-pixel that emits green (as an example, a second color) light, and the third sub-pixel SPX3 may be a blue sub-pixel that emits blue (as an example, a third color) light. The red sub-pixel may provide light in a wavelength band of 600nm to 750nm. The green sub-pixel may provide light in a wavelength band of 480nm to 560nm. The blue sub-pixel may provide light in a wavelength band of 370nm to 460nm.

[0043] According to an embodiment, the sub-pixels SPX may have sizes different from each other. For example, the size of the sub-pixel SPX may be determined according to the light emitting element LD (refer to Figure 2 ) type. For example, the third sub-pixel SPX3 may be larger than the first sub-pixel SPX1 and the second sub-pixel SPX2. According to an embodiment, the second sub-pixel SPX2 may be larger than the first sub-pixel SPX1. For details on this, please refer to Figure 2 To be described later.

[0044] Figure 2 is a schematic cross-sectional view showing a display device according to an embodiment.

[0045] Reference Figure 2 , the display device DD may include a pixel circuit layer PCL including a base layer BSL and a light emitting element layer LEL on the pixel circuit layer PCL. The sub-pixels SPX of the display device DD may form a sub-pixel region SPXA. The sub-pixel region SPXA may include a first sub-pixel region SPXA1 providing light of a first color, a second sub-pixel region SPXA2 providing light of a second color, and a third sub-pixel region SPXA3 providing light of a third color.

[0046] The base layer BSL may form a substrate on which the pixel circuit PXC is arranged. The pixel circuit PXC may be arranged on the base layer BSL and may be configured to drive the light emitting element LD. The pixel circuit layer PCL may include a conductive layer and an insulating layer, and the conductive layer may form the pixel circuit PXC. The pixel circuit PXC may include a circuit element capable of driving the sub-pixel SPX (or the light emitting element LD). The circuit element may include a driving transistor, and may also include an additional transistor and a capacitor.

[0047] The pixel circuit PXC may include: a first pixel circuit PXC1, electrically connected to a first light-emitting element LD1 arranged in a first sub-pixel area SPXA1; a second pixel circuit PXC2, electrically connected to a second light-emitting element LD2 arranged in a second sub-pixel area SPXA2; and a third pixel circuit PXC3, electrically connected to a third light-emitting element LD3 arranged in a third sub-pixel area SPXA3.

[0048] The light emitting element layer LEL may be disposed on the pixel circuit layer PCL. According to an embodiment, the light emitting element layer LEL may include a light emitting element LD. According to an embodiment, the light emitting element layer LEL may further include a bank BNK.

[0049] The light emitting element LD may include: a first light emitting element LD1, included in the first sub-pixel SPX1 and arranged in the first sub-pixel area SPXA1; a second light emitting element LD2, included in the second sub-pixel SPX2 and arranged in the second sub-pixel area SPXA2; and a third light emitting element LD3, included in the third sub-pixel SPX3 and arranged in the third sub-pixel area SPXA3.

[0050] The light emitting element LD may include a first electrode ELT1, a hole transport unit HTU, a light emitting layer EL, an electron transport unit ETU, and a second electrode ELT2.

[0051] The first electrode ELT1 may be arranged on the pixel circuit layer PCL. The first electrode ELT1 may be an anode electrode. The first electrode ELT1 may include: a 1-1st electrode ELT1-1 included in the first light emitting element LD1; a 1-2nd electrode ELT1-2 included in the second light emitting element LD2; and a 1-3rd electrode ELT1-3 included in the third light emitting element LD3. The 1-1st electrode ELT1-1, the 1-2nd electrode ELT1-2, and the 1-3rd electrode ELT1-3 may be separated from each other to form respective anode electrodes of different sub-pixels SPX.

[0052] According to an embodiment, the first electrode ELT1 may include a plurality of conductive materials. For example, the first electrode ELT1 may include one or more of the group consisting of gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), and platinum (Pt), and according to an embodiment, the first electrode ELT1 may also include a transparent conductive material.

[0053] The hole transport unit HTU is configured to transport holes. According to an embodiment, the hole transport unit HTU may include a plurality of hole transporting organic materials, and may also include a p-dopant, a known spin-coated polymer, etc. The hole transport unit HTU may include a multilayer structure having a plurality of layers respectively including materials different from each other. As an example, the hole transport unit HTU may include at least one of a hole injection layer and a hole transport layer, and according to an embodiment, may also include a light-emitting auxiliary layer and an electron blocking layer, etc.

[0054] The hole injection layer may be a layer that performs or improves a hole injection function from the anode electrode to other layers adjacent thereto. The hole transport layer may be a layer that provides holes provided to the light emitting layer EL. The light emitting auxiliary layer may be a layer that compensates for a resonance distance based on the wavelength of light provided by the light emitting layer EL. The electron blocking layer may be a layer that reduces the number of carriers (e.g., holes or electrons) that leave the light emitting layer EL by preventing electrons from being injected from the electron transport unit ETU.

[0055] The hole transport unit HTU may include a first hole transport unit HTU1 included in the first light emitting element LD1, a second hole transport unit HTU2 included in the second light emitting element LD2, and a third hole transport unit HTU3 included in the third light emitting element LD3. According to an embodiment, the first hole transport unit HTU1 to the third hole transport unit HTU3 may include at least a portion of the same layer as each other. However, the present disclosure is not limited thereto.

[0056] The light emitting layer EL may generate light based on an applied current. The light emitting layer EL may be disposed between the hole transport unit HTU and the electron transport unit ETU.

[0057] The light emitting layer EL may include a material capable of emitting light of one color. The light emitting layer EL may include at least a portion of different materials for each sub-pixel SPX. For example, the light emitting layer EL may include an organic light emitting layer BEL and quantum dot light emitting layers QEL1 and QEL2. According to an embodiment, the first light emitting element LD1 and the second light emitting element LD2 may include quantum dot light emitting layers QEL1 and QEL2. The third light emitting element LD3 may include an organic light emitting layer BEL. Accordingly, the display device DD may form a hybrid light emitting structure including two or more different materials.

[0058] The organic light emitting layer BEL may include an organic material. The organic light emitting layer BEL may include a host and a dopant. The host of the light emitting layer EL, as a luminescent substance capable of capturing carriers (electrons and holes) for generating light, can induce excitons to be efficiently generated. The dopant may include a phosphorescent dopant or a fluorescent dopant. According to an embodiment, examples of the dopant are not particularly limited. According to an embodiment, the dopant may include an organic material, or may include a metal complex, etc.

[0059] The first quantum dot light-emitting layer QEL1 and the second quantum dot light-emitting layer QEL2 may include quantum dot compounds. For example, the quantum dot compound may include a crystal of a semiconductor compound. For example, the quantum dot compound may include a semiconductor substance selected from the group consisting of III-VI semiconductor compounds, II-VI semiconductor compounds, III-V semiconductor compounds, IV-VI semiconductor compounds, IV elements or compounds, and combinations thereof. However, the present disclosure is not particularly limited. The diameter of the quantum dot compound is not particularly limited, and since the energy band gap can be adjusted by adjusting the size of the quantum dot compound, the first quantum dot light-emitting layer QEL1 and the second quantum dot light-emitting layer QEL2 can be configured to emit light of one color.

[0060] According to an embodiment, the thickness of the quantum dot light emitting layers QEL1 and QEL2 and the thickness of the organic light emitting layer BEL may be substantially similar to each other. For example, the thickness of the quantum dot light emitting layers QEL1 and QEL2 and the thickness of the organic light emitting layer BEL may be the same as each other.

[0061] According to an embodiment, the quantum dot light emitting layers QEL1 and QEL2 and the organic light emitting layer BEL may be manufactured using an inkjet printing process. The inkjet printing process requires relatively low cost and thus may have excellent manufacturing efficiency.

[0062] However, in the case of manufacturing the quantum dot light emitting layers QEL1 and QEL2 and the organic light emitting layer BEL using an inkjet printing process, it may be difficult to form a desired light emitting structure due to differences in physical properties of inks used to manufacture the respective layers.

[0063] For example, experimentally, when the ink in the first-formed sub-pixel SPX is dried, there may be a concern that the material contained in the ink in the sub-pixel SPX formed later will be damaged. In particular, in order to properly self-assemble the quantum dot light-emitting layers QEL1 and QEL2 in the area where the quantum dot light-emitting layers QEL1 and QEL2 are to be arranged, a certain process time may be required. In this case, as the ink used to form the quantum dot light-emitting layers QEL1 and QEL2 is dried, there may be a concern that the organic material forming the organic light-emitting layer EL will be damaged.

[0064] However, according to an embodiment, the area where the quantum dot light emitting layers QEL1 , QEL2 are arranged may be smaller than the area where the organic light emitting layer BEL is arranged.

[0065] For example, the third sub-pixel SPX3 may have an area larger than the first sub-pixel SPX1 and the second sub-pixel SPX2. The third sub-pixel region SPXA3 may have an area larger than the first sub-pixel region SPXA1 and the second sub-pixel region SPXA2. According to an embodiment, the third opening portion OPN3 (refer to Figure 5 ) can be larger than the first opening OPN1 and the second opening OPN2 (refer to Figure 5 ). The second sub-pixel SPX2 may have an area larger than that of the first sub-pixel SPX1. The second sub-pixel region SPXA2 may have an area larger than that of the first sub-pixel region SPXA1. According to an embodiment, the second opening portion OPN2 may be larger than the first opening portion OPN1.

[0066] Accordingly, the organic light emitting layer BEL may be arranged in a wider region than the first quantum dot light emitting layer QEL1 and the second quantum dot light emitting layer QEL2, and the second quantum dot light emitting layer QEL2 may be arranged in a wider region than the first quantum dot light emitting layer QEL1.

[0067] In this case, the inks for manufacturing the first quantum dot light-emitting layer QEL1 and the second quantum dot light-emitting layer QEL2 (hereinafter, respectively referred to as the first quantum dot ink and the second quantum dot ink) can be supplied to a region (for example, the first opening OPN1 and the second opening OPN2) that is narrower than the region (for example, the third opening OPN3) to which the ink for manufacturing the organic light-emitting layer BEL (hereinafter, referred to as the organic light-emitting layer manufacturing ink) is supplied. Thus, the amount of the first quantum dot ink and the second quantum dot ink dried can be reduced, and as a result, the risk of damage to the organic light-emitting layer BEL caused by the first quantum dot ink and the second quantum dot ink can be reduced.

[0068] In addition, according to an embodiment, the first quantum dot ink and the second quantum dot ink may have a boiling point higher than that of the ink for manufacturing the organic light emitting layer. In this case, when the inkjet process for manufacturing the light emitting layer EL is performed, the first quantum dot ink and the second quantum dot ink are dried faster than the ink for manufacturing the organic light emitting layer within the same time range. Accordingly, as the first quantum dot ink and the second quantum dot ink are dried, the risk of the organic material in the organic light emitting layer EL being damaged can be reduced.

[0069] Furthermore, according to the embodiment, the sizes of the subpixels SPX may be differently configured based on the material characteristics of the light emitting layer EL corresponding to each subpixel SPX, and at the same time, the light emitting layer EL may be manufactured in order of the largest area of ​​the subpixel region SPXA.

[0070] In this case, when the inkjet printing process for manufacturing the light emitting layer EL is performed, the risk of the light emitting layer EL being damaged due to the characteristics of each material can be prevented, thereby improving the reliability of the element characteristics of the light emitting element LD, and the thickness of the light emitting layer EL can be manufactured at a desired thickness. For example, the thickness of the light emitting layer EL can be manufactured substantially uniformly for each sub-pixel SPX. Furthermore, the ink for manufacturing the light emitting layer EL can be dried in a relatively similar drying time for each sub-pixel SPX. For details on this, please refer to the accompanying drawings. Figure 3 The following is a description of the manufacturing method.

[0071] The electron transport unit ETU is configured to transport electrons. According to an embodiment, the electron transport unit ETU may include a plurality of electron transporting materials. For example, the electron transport unit ETU may include an organic material that does not contain a metal, or may include an organic material containing a metal or a plurality of metal materials (for example, alkaline earth metals and / or rare earth metals, etc.). The electron transport unit ETU may include a multilayer structure having a plurality of layers that respectively include materials that are different from each other. For example, the electron transport unit ETU may include at least one of an electron injection layer and an electron transport layer, and according to an embodiment, may also include an electron buffer layer, a hole blocking layer, etc.

[0072] The electron injection layer may be a layer that performs or improves the electron injection function from the cathode electrode to other layers adjacent thereto. The electron transport layer may be a layer that provides the provided electrons to the light emitting layer EL. The hole blocking layer may be a layer that reduces the number of carriers leaving the light emitting layer EL by preventing holes from being injected from the hole transport unit HTU.

[0073] The electron transmission unit ETU may include a first electron transmission unit ETU1 included in the first light emitting element LD1, a second electron transmission unit ETU2 included in the second light emitting element LD2, and a third electron transmission unit ETU3 included in the third light emitting element LD3. According to an embodiment, the first to third electron transmission units ETU1 to ETU3 may include at least a portion of the same layer as each other. However, the present disclosure is not limited thereto.

[0074] The second electrode ELT2 may be disposed on the first to third light emitting elements LD1 to LD3. The second electrode ELT2 may be disposed on the bank BNK. The second electrode ELT2 may be a cathode electrode. The second electrode ELT2 may be a common electrode included in each of the first to third light emitting elements LD1 to LD3.

[0075] The second electrode ELT2 may include a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnOx), indium gallium zinc oxide (IGZO), indium tin zinc oxide (ITZO). However, the present disclosure is not limited thereto. The second electrode ELT2 may also include a conductive material that is somewhat reflective.

[0076] The bank BNK may be disposed on the pixel circuit layer PCL. The bank BNK may protrude in the thickness direction of the base layer BSL and may surround a region when viewed from a plane. Accordingly, the bank BNK may form an opening OPN.

[0077] When an inkjet printing process for manufacturing the light emitting layer EL or the like is performed, the opening OPN formed by the bank BNK may be a region capable of accommodating ink.

[0078] As described above, the bank BNK can form the openings OPN having sizes different from each other. Accordingly, the light emitting layer EL can be formed in the openings OPN that are different for each sub-pixel SPX to be provided.

[0079] The bank BNK may include an organic material. For example, the bank BNK may include one or more of the group consisting of acrylic resin, epoxy resin, phenol resin, polyamide resin, and polyimide resin. However, the present disclosure is not limited thereto.

[0080] Below, refer to Figures 3 to 10 , a method for manufacturing a display device DD according to an embodiment is described. Contents that may overlap with the above contents will be briefly described or not repeated.

[0081] Figure 3 is a schematic flowchart illustrating a method for manufacturing a display device according to an embodiment. Figure 4 is a schematic flow chart showing steps of manufacturing a light emitting layer according to an embodiment.

[0082] Figures 5 to 10 Schematic cross-sectional views showing the manufacturing method of the display device according to the embodiment in each process step. Figures 5 to 10 Based on reference Figure 2 The cross-sectional structure of the display device DD described above shows the process steps respectively.

[0083] Reference Figure 3 According to the embodiment, the manufacturing method of the display device DD may include a step of manufacturing a pixel circuit layer (S100), a step of patterning a first electrode (S200), a step of patterning a dam (S300), a step of manufacturing a hole transport portion (S400), a step of manufacturing a light emitting layer (S500), a step of manufacturing an electron transport portion (S600), and a step of forming a second electrode (S700).

[0084] Reference Figure 4 The step of manufacturing the light-emitting layer (S500) may include the step of manufacturing an organic light-emitting layer (S520), the step of manufacturing a second quantum dot light-emitting layer (S540), and the step of manufacturing a first quantum dot light-emitting layer (S560).

[0085] Reference Figure 3 and Figure 5 , in the step ( S100 ) of manufacturing the pixel circuit layer, the pixel circuit PXC may be patterned on the base layer BSL, and the pixel circuit layer PCL may be provided.

[0086] In this step S100 , a layer for forming a pixel circuit layer PCL may be arranged on the base layer BSL. For example, a first pixel circuit PXC1 , a second pixel circuit PXC2 , and a third pixel circuit PXC3 may be patterned on the base layer BSL.

[0087] According to an embodiment, the conductive layer and the insulating layer on the base layer BSL may be formed based on a conventional process for manufacturing a semiconductor device. For example, the conductive layer or the insulating layer on the base layer BSL may be formed by a photolithography process, may be etched by various methods (wet etching, dry etching, etc.), and may be deposited by various methods (sputtering, chemical vapor deposition, etc.). The present disclosure is not necessarily limited to specific examples.

[0088] Reference Figure 3 and Figure 5 In the step of patterning the first electrode ( S200 ), the first electrodes ELT1 spaced apart from each other may be arranged on the pixel circuit layer PCL.

[0089] In this step S200, the 1-1st electrode ELT1-1, the 1-2nd electrode ELT1-2, and the 1-3rd electrode ELT1-3 for forming an anode electrode may be patterned. Although not shown in the drawings, each of the 1-1st electrode ELT1-1, the 1-2nd electrode ELT1-2, and the 1-3rd electrode ELT1-3 may be electrically connected to the first pixel circuit PXC1 to the third pixel circuit PXC3.

[0090] Reference Figure 3and Figure 5 In the step of patterning the bank ( S300 ), a bank BNK surrounding a region may be arranged.

[0091] In this step S300, as the bank BNK is patterned, a space capable of accommodating ink may be formed in the inkjet printing process for manufacturing the light emitting layer EL.

[0092] In this step S300, the bank BNK may be patterned to surround a region when viewed from a plane to form an opening OPN. For example, the bank BNK may surround a region for forming the first sub-pixel region SPXA1 to the third sub-pixel region SPXA3 (for example, a region for forming the first light-emitting element LD1 to the third light-emitting element LD3), thereby forming the first opening OPN1 to the third opening OPN3.

[0093] In this step S300, the third opening portion OPN3 may be formed to be larger than the first opening portion OPN1 and the second opening portion OPN2. The second opening portion OPN2 may be formed to be larger than the first opening portion OPN1. According to an embodiment, the size of each opening portion OPN may correspond to the aperture ratio of the corresponding sub-pixel area SPXA. Accordingly, the aperture ratio of the third sub-pixel SPX3 may be larger than the aperture ratios of the first sub-pixel SPX1 and the second sub-pixel SPX2, and the aperture ratio of the second sub-pixel SPX2 may be larger than the aperture ratio of the first sub-pixel SPX1.

[0094] Reference Figure 3 and Figure 6 , in the step of manufacturing the hole transport unit ( S400 ), the hole transport unit HTU of each of the first to third sub-pixels SPX1 to SPX3 may be disposed within the opening portion OPN.

[0095] In this step S400, in order to form the hole transport unit HTU, two or more layers may be stacked in sequence. According to an embodiment, the layers used to form the hole transport unit HTU may be arranged by vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB), inkjet printing, laser printing, laser induced thermal imaging (LITI), and other methods.

[0096] In this step S400 , the first hole transport unit HTU1 may be disposed in the first opening OPN1 , the second hole transport unit HTU2 may be disposed in the second opening OPN2 , and the third hole transport unit HTU3 may be disposed in the third opening OPN3 .

[0097] According to an embodiment, at least a portion of layers in the first to third hole transport units HTU1 to HTU3 may be patterned within the same process. However, the present disclosure is not limited thereto.

[0098] Reference Figure 3 , Figure 4 and Figure 7 In the step of manufacturing the light emitting layer ( S500 ), the step of manufacturing the organic light emitting layer ( S520 ) may be performed.

[0099] In this step S520 , the organic light emitting layer BEL may be patterned in the third opening OPN3 .

[0100] According to an embodiment, the organic light emitting layer BEL may be arranged using an inkjet printing process. According to an embodiment, in order to be able to perform the inkjet printing process, an inkjet printer including a nozzle configured to eject a fluid may be used. For example, in order to provide the organic light emitting layer BEL, an organic light emitting layer manufacturing ink including an organic light emitting material and a solvent for manufacturing the third sub-pixel SPX3 may be supplied to the third opening portion OPN3 corresponding to the third sub-pixel area SPXA3 (for example, overlapping the third sub-pixel area SPXA3). The organic light emitting layer BEL, as a layer included in the third sub-pixel SPX3, may be supplied to the third opening portion OPN3 having an opening ratio larger than that of the first sub-pixel SPX1 and the second sub-pixel SPX2.

[0101] According to an embodiment, the solvent included in the ink for manufacturing the organic light emitting layer may include an organic solvent. The solvent included in the ink for manufacturing the organic light emitting layer may include two or more solvents. The solvent included in the ink for manufacturing the organic light emitting layer may include a plurality of solvents having a boiling point lower than that of the solvent included in the first quantum dot ink and the second quantum dot ink. For example, the solvent included in the ink for manufacturing the organic light emitting layer may include two or more solvents so that the solvent included in the ink for manufacturing the organic light emitting layer has a boiling point lower than that of the solvent included in the first quantum dot ink and the second quantum dot ink. For example, in the case where the solvent included in the ink for manufacturing the organic light emitting layer has a boiling point lower than that of the solvent included in the first quantum dot ink and the second quantum dot ink, one or more of propylene glycol methyl ether acetate (PGMEA: Propylene Glycol Methyl Ether Acetate), dipropylene glycol n-propyl ether (DPNP: DipropyleneGlycol n-Propyl Ether) and triethylene glycol n-butyl ether (Triethylene Gylcol n-Butyl Ether) may be included. However, the present disclosure is not limited to the above examples.

[0102] When the step S520 is performed, the first quantum dot ink and the second quantum dot ink may be in a state of not being arranged in the first opening portion OPN1 and the second opening portion OPN2 .

[0103] According to an embodiment, after the organic light emitting layer manufacturing ink is ejected, a drying process may be performed to manufacture the organic light emitting layer BEL. The drying process may include a process of removing the solvent under a temperature range and a vacuum environment. For example, the temperature range may be 25° C. to 75° C. As the above temperature range is satisfied and the drying process is performed under a vacuum environment, the solvent can be effectively removed without damaging the properties of the ejected material.

[0104] According to an embodiment, the organic light emitting layer manufacturing ink may have a boiling point lower than that of the first quantum dot ink and the second quantum dot ink by including a solvent having a lower boiling point. Accordingly, even if the organic light emitting layer manufacturing ink is ejected onto the pixel circuit layer PCL at a relatively early time point, it may be sufficiently dried within a period of time substantially similar to that of the first quantum dot ink and the second quantum dot ink ejected thereafter.

[0105] Reference Figure 3 , Figure 4 and Figure 8 In the step of manufacturing the light emitting layer (S500), the step of manufacturing the second quantum dot light emitting layer (S540) may be performed.

[0106] According to an embodiment, the second quantum dot light-emitting layer QEL2 may be arranged using an inkjet printing process. For example, in order to provide the second quantum dot light-emitting layer QEL2, a second quantum dot ink including a quantum dot compound for manufacturing the second sub-pixel SPX2 and a solvent may be supplied to a second opening portion OPN2 corresponding to the second sub-pixel region SPXA2 (e.g., overlapping the second sub-pixel region SPXA2). The second quantum dot light-emitting layer QEL2, as a layer included in the second sub-pixel SPX2, may be supplied to the second opening portion OPN2 forming an opening ratio that is smaller than the opening ratio of the third sub-pixel SPX3 and larger than the opening ratio of the first sub-pixel SPX1.

[0107] When performing this step S540 , the organic light emitting layer BEL may be in an arranged state and the first quantum dot light emitting layer QEL1 may be in an unarranged state.

[0108] According to an embodiment, after the second quantum dot ink is ejected, a drying process may be performed to manufacture the second quantum dot light-emitting layer QEL2. The drying process may include a process of removing the solvent in a temperature range and a vacuum environment. For example, the temperature range may be 25° C. to 75° C. As the above temperature range is met and the drying process is performed in a vacuum environment, the solvent can be effectively removed without damaging the properties of the ejected material.

[0109] Reference Figure 3 , Figure 4 and Fig. 9 In the step of manufacturing the light-emitting layer ( S500 ), a step of manufacturing a first quantum dot light-emitting layer ( S560 ) may be performed.

[0110] According to an embodiment, the first quantum dot light emitting layer QEL1 may be arranged using an inkjet printing process. For example, in order to provide the first quantum dot light emitting layer QEL1, a first quantum dot ink including a quantum dot compound for manufacturing the first sub-pixel SPX1 and a solvent may be supplied to a first opening portion OPN1 corresponding to the first sub-pixel region SPXA1 (e.g., overlapping the first sub-pixel region SPXA1). The first quantum dot light emitting layer QEL1, as a layer included in the first sub-pixel SPX1, may be supplied to the first opening portion OPN1 forming an opening ratio smaller than the opening ratios of the second sub-pixel SPX2 and the third sub-pixel SPX3.

[0111] When performing this step S560, the organic light-emitting layer BEL and the second quantum dot light-emitting layer QEL2 may be in an arranged state.

[0112] According to an embodiment, after the first quantum dot ink is ejected, a drying process may be performed to manufacture the first quantum dot light-emitting layer QEL1. The drying process may include a process of removing the solvent in a temperature range and a vacuum environment. For example, the temperature range may be 25° C. to 75° C. As the above temperature range is met and the drying process is performed in a vacuum environment, the solvent can be effectively removed without damaging the properties of the ejected material.

[0113] According to an embodiment, a drying process may also be performed after ejecting both the first quantum dot ink and the second quantum dot ink. In this case, similar to the above, the drying process may include a process of removing the solvent under a temperature range and a vacuum environment, and the temperature range may be 25°C to 75°C.

[0114] According to an embodiment, the solvent included in the first quantum dot ink and the second quantum dot ink may include an organic solvent. The solvent included in the first quantum dot ink and the second quantum dot ink may include two or more solvents. The solvent included in the first quantum dot ink and the second quantum dot ink may include a plurality of solvents having a boiling point higher than that of the solvent included in the ink for manufacturing the organic light emitting layer. For example, the solvent included in the first quantum dot ink and the second quantum dot ink may include two or more solvents so that the solvent included in the first quantum dot ink and the second quantum dot ink has a boiling point higher than that of the solvent included in the ink for manufacturing the organic light emitting layer. For example, in the case where the solvent included in the first quantum dot ink and the second quantum dot ink has a boiling point higher than that of the solvent included in the ink for manufacturing the organic light emitting layer, one or more of propylene glycol methyl ether acetate (PGMEA: Propylene Glycol Methyl Ether Acetate), dipropylene glycol n-propyl ether (DPNP: Dipropylene Glycol n-Propyl Ether) and triethylene glycol n-butyl ether (Triethylene Gylcol n-Butyl Ether) may be used. However, the present disclosure is not limited to the above examples.

[0115] According to an embodiment, the first quantum dot ink and the second quantum dot ink may have a boiling point higher than that of the ink for manufacturing the organic light emitting layer. Accordingly, even if the first quantum dot ink and the second quantum dot ink are ejected into the first opening OPN1 and the second opening OPN2 in a later period of time than the ink for manufacturing the organic light emitting layer, the time points at which the drying steps of the first quantum dot ink, the second quantum dot ink and the ink for manufacturing the organic light emitting layer are finished may be substantially similar.

[0116] Furthermore, as the time for the solvents of the first and second quantum dot inks to be dried is reduced, the risk of the dried solvent damaging the organic material included in the organic light emitting layer BEL can be reduced.

[0117] In addition, as mentioned above, the organic light-emitting layer manufacturing ink ejected earlier may have a lower boiling point than the first quantum dot ink and the second quantum dot ink ejected in a later time period. Experimentally, in the case of an inkjet printing process, as part of the solvent in the ink ejected earlier is dried, the dried solvent may affect the formation of the thickness of the light-emitting layer EL in other adjacent areas. However, according to an embodiment, the boiling point of the organic light-emitting layer manufacturing ink ejected earlier may be configured to be lower, in which case the risk of the organic light-emitting layer manufacturing ink affecting the thickness formation of the light-emitting layer EL in other areas can be reduced. Ultimately, the process sequence and the physical properties of the ink, etc. can be specially designed based on the material properties, and the thickness of the light-emitting layer EL according to the embodiment can be appropriately defined based on the desired thickness range.

[0118] In addition, as the first quantum dot ink and the second quantum dot ink with a high boiling point are sprayed into the narrower first opening OPN1 and the second opening OPN2, the amount of solvent of the first quantum dot ink and the second quantum dot ink dried is reduced. Similarly, the risk of the dried solvent damaging the organic material contained in the organic light-emitting layer BEL can be reduced.

[0119] Reference Figure 3 and Fig.10 In the step of manufacturing the electron transmission unit ( S600 ), the electron transmission unit ETU of each of the first to third sub-pixels SPX1 to SPX3 may be disposed within the opening OPN.

[0120] In this step S600, in order to form the electron transport unit ETU, two or more layers may be stacked in sequence. According to an embodiment, the layers used to form the electron transport unit ETU may be arranged by vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB), inkjet printing, laser printing, laser induced thermal imaging (LITI), and other methods.

[0121] In this step S600 , the first electron transmission unit ETU1 may be arranged in the first opening OPN1 , the second electron transmission unit ETU2 may be arranged in the second opening OPN2 , and the third electron transmission unit ETU3 may be arranged in the third opening OPN3 .

[0122] According to an embodiment, at least a portion of layers in the first to third electron transporting units ETU1 to ETU3 may be patterned in the same process. However, the present disclosure is not limited thereto.

[0123] Combination Figure 2 , refer to Figure 3In the step of forming the second electrode ( S700 ), the second electrode ELT2 for forming a cathode electrode may be formed.

[0124] In the present step S700 , first to third light emitting elements LD1 to LD3 formed in the first to third sub-pixel regions SPXA1 to SPXA3 may be provided.

[0125] Thereafter, according to the embodiment, an additional layer (window, etc.) may be further disposed on the light emitting element layer LEL, so that the display device DD according to the embodiment may be manufactured.

[0126] As described above, although the preferred embodiments of the present disclosure have been described with reference to them, any person skilled in the art or having ordinary knowledge in the technical field to which the present invention pertains will understand that various modifications and changes may be made to the present disclosure without departing from the concept of the present disclosure and the technical field described in the claims.

[0127] Therefore, the technical scope of the present disclosure should not be limited by the contents described in the detailed description of the specification but should be determined by the claims.

Claims

1. A display device, comprising a sub-pixel, wherein the sub-pixel comprises: a first sub-pixel, forming a first sub-pixel region providing light of a first color; a second sub-pixel, forming a second sub-pixel region providing light of a second color; as well as A third sub-pixel is formed to provide a third sub-pixel region for providing light of a third color, The area of ​​the third sub-pixel region is larger than the area of ​​the first sub-pixel region and the area of ​​the second sub-pixel region. Each of the first sub-pixel and the second sub-pixel includes a quantum dot light-emitting element including a quantum dot light-emitting layer, The third sub-pixel includes an organic light emitting element including an organic light emitting layer.

2. The display device according to claim 1, wherein: The area of ​​the second sub-pixel region is larger than the area of ​​the first sub-pixel region. Wherein, the first sub-pixel is a red sub-pixel, The second sub-pixel is a green sub-pixel, The third sub-pixel is a blue sub-pixel.

3. The display device according to claim 1, wherein: The quantum dot light-emitting layer includes a first quantum dot light-emitting layer included in the first sub-pixel and a second quantum dot light-emitting layer included in the second sub-pixel, The thickness of the organic light-emitting layer, the first quantum dot light-emitting layer and the second quantum dot light-emitting layer are the same.

4. The display device according to claim 1, further comprising: a bank surrounding an area where the quantum dot light-emitting layer and the organic light-emitting layer are arranged, The bank forms a first opening portion overlapping the first sub-pixel region, a second opening portion overlapping the second sub-pixel region, and a third opening portion overlapping the third sub-pixel region.

5. The display device according to claim 1, wherein: The quantum dot light-emitting layer includes a quantum dot compound, The organic light emitting layer includes an organic material.

6. The display device according to claim 1, wherein: Each of the quantum dot light emitting element and the organic light emitting element further includes a first electrode, a hole transport portion, an electron transport portion, and a second electrode.

7. A method for manufacturing a display device, wherein the display device comprises a sub-pixel, wherein the sub-pixel comprises: a first sub-pixel, forming a first sub-pixel region providing light of a first color; a second sub-pixel, forming a second sub-pixel region providing light of a second color; and a third sub-pixel, forming a third sub-pixel region providing light of a third color, The manufacturing method comprises the following steps: manufacturing a pixel circuit layer; patterning a bank on the pixel circuit layer; and manufacturing a light emitting layer in the opening formed by the bank, The openings include a first opening in the first sub-pixel region, a second opening in the second sub-pixel region, and a third opening in the third sub-pixel region. The steps of manufacturing the light-emitting layer include the following steps: manufacturing an organic light-emitting layer in the third opening; manufacturing a second quantum dot light-emitting layer in the second opening; and manufacturing a first quantum dot light-emitting layer in the first opening, When viewed from a plane, the third opening has an area larger than the first opening and the second opening. The step of manufacturing the organic light-emitting layer is performed before the step of manufacturing the first quantum dot light-emitting layer and the step of manufacturing the second quantum dot light-emitting layer.

8. The method for manufacturing a display device according to claim 7, wherein: The step of manufacturing the light emitting layer further includes the step of performing an inkjet printing process.

9. The method for manufacturing a display device according to claim 8, wherein: The step of manufacturing the organic light-emitting layer includes the step of jetting an ink for manufacturing the organic light-emitting layer onto the pixel circuit layer. The step of manufacturing the first quantum dot light-emitting layer includes the step of spraying a first quantum dot ink onto the pixel circuit layer; The step of manufacturing the second quantum dot light-emitting layer includes the step of jetting a second quantum dot ink onto the pixel circuit layer.

10. The method for manufacturing a display device according to claim 9, wherein: The first quantum dot ink and the second quantum dot ink include the same solvent as each other.

11. The method for manufacturing a display device according to claim 9, wherein: The first quantum dot ink, the second quantum dot ink, and the ink for manufacturing an organic light-emitting layer each include two or more solvents.

12. The method for manufacturing a display device according to claim 9, wherein: The first quantum dot ink, the second quantum dot ink, and the ink for manufacturing the organic light-emitting layer each include an organic solvent.

13. The method for manufacturing a display device according to claim 9, wherein: The organic light emitting layer manufacturing ink has a boiling point lower than boiling points of the first quantum dot ink and the second quantum dot ink.

14. The method for manufacturing a display device according to claim 9, wherein: The step of manufacturing the light-emitting layer further comprises the following steps: The solvents of the first quantum dot ink, the second quantum dot ink, and the organic light emitting layer manufacturing ink are dried. The drying step is performed at a temperature ranging from 25° C. to 75° C. and in a vacuum environment.

15. The method for manufacturing a display device according to claim 9, wherein: After performing the step of manufacturing the organic light-emitting layer, the step of manufacturing the second quantum dot light-emitting layer is performed, and after performing the step of manufacturing the second quantum dot light-emitting layer, the step of manufacturing the first quantum dot light-emitting layer is performed.

16. The method for manufacturing a display device according to claim 8, wherein: Each of the first quantum dot light-emitting layer and the second quantum dot light-emitting layer comprises a quantum dot compound, The organic light-emitting layer comprises an organic material, The organic light emitting layer, the first quantum dot light emitting layer, and the second quantum dot light emitting layer have the same thickness as each other.

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