Display using quantum dot as light-emitting layer and method for manufacturing same

Abstract

According to one embodiment disclosed in the present document, disclosed is a method for manufacturing a display, the method comprising the steps of: forming a plurality of first electrodes on a substrate; continuously forming a light-emitting layer from one side of the substrate to the other side of the substrate in a state in which a potential difference is formed between the substrate on which a plurality of first electrodes are formed and a nozzle in which a light-emitting solution is accommodated; and forming a second electrode on the substrate on which the light-emitting layer is formed, wherein the light-emitting solution includes quantum dots including a ligand of a polar material, and a conductive solvent. Various other embodiments identified through the specification are possible.

Description

Display using quantum dots as a light-emitting layer and manufacturing method thereof

[0001] Embodiments disclosed in this document relate to a display using quantum dots as a light-emitting layer and a method for manufacturing the same.

[0002] Quantum dots (QDs) can control the wavelength of light they emit by adjusting their diameter. They also possess the inherent stability of inorganic materials and excellent color purity and expression due to their narrow full width at half maximum (FWHM). Based on these advantages, QDs are being widely studied in biosensors, solar cells, medical applications, and displays.

[0003] Quantum dots are measured in nanometers (nm) in size, and unlike conventional organic light-emitting diodes (OLEDs) that utilize organic materials, they cannot be deposited in a vacuum. Forming a thin film of quantum dots requires a solution-based process, primarily spin coating, though inkjet printing is gaining traction recently.

[0004] The above information may be provided as background art to aid in understanding the present disclosure. No claim or determination is made as to whether any of the above is applicable as prior art in connection with the present disclosure.

[0005] According to one embodiment disclosed in the present document, a method for manufacturing a display including a plurality of sub-pixels includes the steps of forming a plurality of first electrodes on a substrate, continuously printing the luminescent solution from one side of the substrate to the other side of the substrate while a potential difference is formed between the substrate on which the plurality of first electrodes are formed and a nozzle containing a luminescent solution to form a luminescent layer corresponding to each of the plurality of sub-pixels, and forming a second electrode on the substrate on which the luminescent layer is formed, wherein the luminescent solution may include a quantum dot including a ligand of a polar material and a conductive solvent so as to be able to move along an electric field caused by the potential difference.

[0006] According to one embodiment disclosed in the present document, a display including a plurality of sub-pixels that implement different colors includes a substrate, a plurality of first electrodes disposed on the substrate, a second electrode disposed on the plurality of first electrodes, and an emission layer disposed between each of the plurality of first electrodes and the second electrode and corresponding to each of the plurality of sub-pixels, wherein the emission layer is formed of a quantum dot including a ligand having an electrical polarity that generates an attractive force in a direction toward the substrate, and the quantum dot can have a zeta potential.

[0007] FIG. 1A is a plan view of a display according to one embodiment.

[0008] FIG. 1b is a cross-sectional view of a display according to one embodiment.

[0009] FIG. 2 is a drawing showing an electroluminescent structure of a display according to one embodiment.

[0010] FIG. 3A is a drawing showing a quantum dot light-emitting layer of a display according to one embodiment.

[0011] FIG. 3b is a schematic diagram illustrating the structure of quantum dots constituting a display light-emitting layer according to one embodiment.

[0012] FIG. 3c is a drawing for explaining a method of imparting polarity to quantum dots constituting a light-emitting layer of a display according to one embodiment.

[0013] FIG. 3D is a drawing for explaining a method for manufacturing ink for printing a light-emitting layer of a display according to one embodiment.

[0014] FIG. 3e is a drawing for explaining the characteristics of quantum dots constituting the light-emitting layer of a display according to one embodiment.

[0015] FIGS. 4a, 4b, 4c, and 4d are drawings for explaining a manufacturing process of a light-emitting layer of a display according to one embodiment.

[0016] FIGS. 5A and 5B are drawings for explaining a method of printing a light-emitting layer of a display according to one embodiment.

[0017] FIGS. 6A, 6B, and 6C are drawings for explaining a method of stacking quantum dots in a process of printing a light-emitting layer of a display according to one embodiment.

[0018] Figure 7a is a plan view of a first embodiment of the display.

[0019] Figure 7b is a cross-sectional view of a first embodiment of the display.

[0020] FIG. 8a, FIG. 8b, and FIG. 8c are drawings for explaining a method for manufacturing a light-emitting layer of a display according to the first embodiment.

[0021] Figure 9a is a plan view of a second embodiment of the display.

[0022] Figure 9b is a cross-sectional view of a second embodiment of the display.

[0023] FIG. 10a, FIG. 10b, and FIG. 10c are drawings for explaining a method for manufacturing a light-emitting layer of a display according to a second embodiment.

[0024] Fig. 11 is a drawing for explaining the light-emitting area of ​​the display according to the second embodiment.

[0025] Figure 12 is a cross-sectional view of a third embodiment of the display.

[0026] FIG. 13a, FIG. 13b, and FIG. 13c are drawings for explaining a method for manufacturing a light-emitting layer of a display according to a third embodiment.

[0027] Fig. 14 is a cross-sectional view showing a light-blocking member of a display according to the first embodiment.

[0028] Fig. 15a is a cross-sectional view showing a first form of a light-blocking member of a display according to a second embodiment.

[0029] FIG. 15b is a cross-sectional view showing a second form of a light-blocking member of a display according to a second embodiment.

[0030] Fig. 16 is a schematic drawing showing how the light-emitting layer of a display is uniformly formed according to the first embodiment.

[0031] Fig. 17 is a schematic drawing showing a uniform formation of a light-emitting layer of a display according to a second embodiment.

[0032] FIG. 18 is a drawing for explaining the width of the light-emitting layer of a display according to one embodiment.

[0033] FIG. 19 is a schematic diagram illustrating a transistor structure inside a display according to one embodiment.

[0034] FIG. 20 is a block diagram of an electronic device within a network environment according to various embodiments.

[0035] FIG. 21 is a block diagram of a display module according to various embodiments.

[0036] In connection with the description of the drawings, the same or similar reference numerals may be used for identical or similar components.

[0037] Hereinafter, various embodiments of the present invention will be described with reference to the attached drawings. However, this is not intended to limit the present invention to specific embodiments, and it should be understood that the present invention encompasses various modifications, equivalents, and / or alternatives of the embodiments.

[0038] The present invention aims to provide a method for printing a quantum dot light-emitting layer of a display using an electrohydrodynamic printing process, in which the quantum dots are electrically polarized and an electric field is formed in a substrate and a nozzle, so that the quantum dots are immediately printed on the substrate by electrophoresis. Through the present invention, the quantum dot light-emitting layer can be printed uniformly and thinly on the substrate, enabling nano-single-layer pattern printing of various line widths. In addition, it is possible to manufacture a display with a high resolution that is not possible with the existing inkjet process. Since the light-emitting layer can be printed without a pixel-defining layer, it has the effects of simplifying the structure of the display panel, reducing the number of process steps, and reducing material costs.

[0039] FIG. 1A is a plan view of a display according to one embodiment.

[0040] FIG. 1b is a cross-sectional view of a display according to one embodiment.

[0041] Fig. 1a is a drawing showing the display as viewed from the +z-axis direction. In Fig. 1a, only some components (e.g., hole transport layer (140), light-emitting layer (150)) are shown to aid understanding. Fig. 1b is a drawing showing a cross-section of a part of the display cut in the x-axis direction.

[0042] Referring to FIGS. 1A and 1B, the display (100) may include a plurality of pixels (PXL). In FIG. 1B, for convenience of explanation, only one sub-pixel (SP1) of one pixel (PXL) is illustrated. The pixel (PXL) may include a first sub-pixel (SP1), a second sub-pixel (SP2), and a third sub-pixel (SP3) that implement three different colors. For example, the pixel (PXL) may include a first sub-pixel (SP1) that implements green, a second sub-pixel (SP2) that implements red, and a third sub-pixel (SP3) that implements blue. Alternatively, in one embodiment, the pixel (PXL) may include a fourth sub-pixel (not shown) that emits white light in addition to the first sub-pixel (SP1), the second sub-pixel (SP2), and the third sub-pixel (SP3). The display (100) may implement various colors by controlling the amount of light of each of the sub-pixels (SP1, SP2, and SP3). Each sub-pixel (SP1, SP2, SP3) may include a light-emitting element (101) and a transistor layer (120) arranged on a substrate (110).

[0043] In one embodiment, the display device (100) may include a substrate (110), a transistor layer (120), and a light-emitting element (101). As an example, the light-emitting element (101) may include a first electrode layer (130), a hole transport layer (140), a light-emitting layer (150), an electron transport layer (160), and a second electrode layer (170).

[0044] The substrate (110) may be mainly formed of glass, and may serve as a foundation on which a transistor layer (120), a first electrode layer (130), a hole transport layer (140), a light-emitting layer (150), an electron transport layer (160), and a second electrode layer (170) are sequentially laminated. The transistor layer (120) may be disposed on the upper portion (e.g., +z-axis) of the substrate (110). In addition, the transistor layer (120) may include a plurality of signal lines and pixel circuits. For example, any one of the plurality of transistors may control the amount of current applied to the sub-pixels (SP1, SP2, SP3) of each pixel (PXL) to control the brightness of each pixel (PXL) constituting the screen of the display (100). For example, any one of the plurality of transistors may serve as an electrical switch for turning on and off the sub-pixels (SP1, SP2, SP3). At least one of the plurality of transistors may be formed of a thin film transistor. At least one active layer (or semiconductor layer) of the plurality of transistors may be formed of any one of amorphous silicon (a-si), low-temperature polycrystalline silicon (LTPS), and oxide.

[0045] The first electrode layer (130) may be disposed on the upper portion of the transistor layer (120) (e.g., on the +z-axis). The first electrode layer (130) may include a plurality of first electrodes that are spaced apart from each other on the transistor layer (120). The plurality of first electrodes may be disposed spaced apart from each other by a predetermined interval in a first direction (e.g., x-axis direction) and a second direction (e.g., y-axis direction). For example, the plurality of first electrodes may be arranged in a matrix shape. That is, the plurality of first electrodes may be arranged in a shape substantially the same as or similar to that of the light-emitting layer (150) illustrated in FIG. 1A. The plurality of first electrodes may be formed as transmissive electrodes or reflective electrodes. For example, each of the plurality of first electrodes may be formed in a single-layer or multi-layer structure using at least one of a first conductive film and a second conductive film. For example, the first conductive film may be a reflective film formed of a compound comprising at least one of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, and Cr, or a combination of two or more thereof. In addition, the second conductive film may be a transparent conductive film formed of any one of ITO, IZO, and ZnO. In one embodiment, the first electrode layer (130) may be formed as an anode and may be a starting point for moving holes to the light-emitting layer (150) through the hole transport layer (140).

[0046] The hole transport layer (140) may be disposed on the upper portion of the first electrode layer (130) (e.g., on the +z axis). The hole transport layer (140) may be disposed in contact with a plurality of first electrodes and spaced apart from the transistor layer (120) by a predetermined distance (e.g., L1). The hole transport layer (140) may be formed substantially parallel to the transistor layer (120) (e.g., parallel to the y axis). The hole transport layer (140) may be formed of a low-molecular organic material or a high-molecular organic material, and may enable holes to be efficiently transported from the first electrode layer (130) to the light-emitting layer (150). In one embodiment, the hole transport layer (140) may further include a hole injection layer (not shown) that increases the injection efficiency of holes from the first electrode layer (130).

[0047] The light-emitting layer (150) may be arranged on the upper portion of the hole transport layer (140) (e.g., above the +z axis). The light-emitting layer (150) may include a first color light-emitting layer (151), a second color light-emitting layer (152), and a third color light-emitting layer (153) that implement different colors on the hole transport layer (140). Each of the light-emitting layers (151, 152, 153) may be arranged on the hole transport layer (140) at a predetermined interval in a first direction (e.g., x-axis direction) and / or a second direction (e.g., y-axis direction). Accordingly, at least a portion of the light-emitting layer (150) may be arranged in a matrix form and / or a stripe form. That is, when the substrate (110) on which the light-emitting layer (150) is formed is viewed from the +y-axis direction, the hole transport layer (140) can be seen (visible) between the light-emitting layer (151) of the first color and the light-emitting layer (152) of the second color. The light-emitting layers (150) spaced apart in the first direction (e.g., x-axis direction) can form a light-emitting layer (150) that implements the same color. For example, the light-emitting layer (151) of the first color can have a plurality of light-emitting layers of the first color spaced apart in the first direction (e.g., x-axis direction). In the light-emitting layer (150), holes that have moved through the first electrode layer (130) and electrons that have moved through the second electrode layer (170) combine to provide electrical energy, so that light having a designated wavelength can be emitted in one direction (e.g., in the direction of the arrow (or +z-axis direction)). The light-emitting layer (150) may include quantum dots (e.g., quantum dots (300) of FIG. 3a). The quantum dots (300) will be described in detail later with reference to FIGS. 3a to 6c.

[0048] In one embodiment, the line width (e.g., W1) of each light-emitting layer (151, 152, 153) corresponding to each of the sub-pixels (SP1, SP2, SP3) may be formed to be several um (e.g., 5 um) or less. Alternatively, as an example, the line width (e.g., W2) of a pixel (PXL) composed of a first color light-emitting layer (151), a second color light-emitting layer (152), and a third color light-emitting layer (153) may be formed to be several tens of um (e.g., 15 um) or less.

[0049] The electron transport layer (160) may be disposed on the upper portion of the light-emitting layer (150) (e.g., above the +z axis). The electron transport layer (160) may be formed of a low-molecular organic material or a high-molecular organic material, and may enable electrons to be efficiently transported from the second electrode layer (170) to the light-emitting layer (150). In one embodiment, the electron transport layer (160) may further include an electron injection layer (not shown) that increases the injection efficiency of electrons from the second electrode layer (170).

[0050] The second electrode layer (170) may be disposed on the upper portion (e.g., along the +z axis) of the electron transport layer (160). Unlike the first electrode layer (130) including a plurality of first electrodes that are spaced apart from each other, the second electrode layer (170) may be formed as a single second electrode. Accordingly, the second electrode may be formed to have a size corresponding to that of the substrate (110) (e.g., the area of ​​the surface perpendicular to the z axis is substantially the same size). The second electrode layer (170) may be formed as a transmissive electrode or a reflective electrode. For example, the second electrode layer (170) may be formed in a single-layer or multi-layer structure using at least one of the first conductive film and the second conductive film. For example, the first conductive film may be a reflective film formed of a compound including at least one of Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, and Cr, or a combination of two or more thereof. Additionally, the second conductive film may be a transparent conductive film formed of any one of ITO, IZO, and ZnO. In one embodiment, the second electrode layer (170) may be formed as an anode and may serve as a starting point for moving electrons to the light-emitting layer (150) through the electron transport layer (160).

[0051] In various embodiments, the display (100) may have a structure inside that may vary depending on the polarity of the electrodes, and is not limited to the structure described above. For example, the first electrode layer may be formed as a cathode, and in this case, the second electrode layer may be formed as an anode to have a polarity opposite to that of the first electrode layer. Accordingly, an electron transport layer may be disposed on the upper portion of the first electrode layer (e.g., in the +z-axis direction), and a hole transport layer may be disposed on the lower portion of the second electrode layer (e.g., in the -z-axis direction). However, for convenience of explanation, the following description will be made based on an embodiment of the display (100) in which the first electrode layer is formed as an anode and the second electrode layer is formed as a cathode.

[0052] FIG. 2 is a drawing showing an electroluminescent structure of a display according to one embodiment.

[0053] Referring to FIG. 2, in one embodiment, the display (100) may include a light-emitting element (201). The light-emitting element (201) may include a first electrode layer (130), a hole injection layer (135), a hole transport layer (140), a light-emitting layer (150), an electron transport layer (160), an electron injection layer (165), and a second electrode layer (170). Holes may move from the first electrode layer (130) through the hole injection layer (135) and the hole transport layer (140) to the light-emitting layer (150), and electrons may move from the second electrode layer (170) through the electron injection layer (165) and the electron transport layer (160) to the light-emitting layer (150). In the light-emitting layer (150), electrons and holes may combine to emit light. In one embodiment, the first electrode layer (130) may correspond to the anode and the second electrode layer (170) may correspond to the cathode. In addition, in one embodiment, the light emitting element (201) may further include an electron block layer or a hole block layer to improve optical efficiency.

[0054] FIG. 3A is a drawing showing a quantum dot light-emitting layer of a display according to one embodiment.

[0055] Referring to FIG. 3A, in one embodiment, the light-emitting layer (150) may include quantum dots (300). The light-emitting layer (150) may be formed by stacking at least one layer of quantum dots (300). For example, the quantum dots (300) may be uniformly arranged in the z-axis direction between the hole transport layer (140) and the electron transport layer (160).

[0056] FIG. 3b is a schematic diagram illustrating the structure of quantum dots constituting a light-emitting layer of a display according to one embodiment.

[0057] Referring to FIG. 3B, in one embodiment, the quantum dot (300) may include a core (340), a shell (350), a ligand (360), and a polar material (370). For example, the quantum dot (300) may be formed in a structure in which the shell (350) surrounds the core (340), and the ligand (360) is attached to the outer surface of the shell (350). The core (340) and the shell (350) may be formed of the same material. Alternatively, in one embodiment, the core (340), the shell (350), and the ligand (360) may be formed of different materials. For example, the core (340) may include zinc oxide, and the shell (350) may include P, N, C, Cl, F, Br, S, or a combination thereof. Alternatively, in one embodiment, the shell (350) may include Zn3P2, Zn3[(PO)4]2, ZnHPO3, Zn3N2, ZnS, ZnSO4, ZnCl2, ZnBr2, ZnF2, or a combination thereof. In one embodiment, the ligand (360) may be formed of a non-polar organic material. For example, the ligand (360) may be formed of a compound derived from a metal halide, a compound derived from a carboxylic acid, a compound derived from a thiol, or a combination thereof. Due to the polar material (370) substituted (or synthesized) for the ligand (360) of the quantum dot (300), the quantum dot (300) may be polar and may have a zeta potential when mixed with a solvent and present in a solution. A method for replacing (or synthesizing) a ligand (360) from a nonpolar organic substance to a polar substance (e.g., a polar organic substance) is described later in FIG. 3c.

[0058] FIG. 3c is a drawing for explaining a method of imparting polarity to quantum dots constituting a light-emitting layer of an electroluminescent display device according to one embodiment.

[0059] Referring to FIG. 3C, in one embodiment, the quantum dot in its original state (e.g., before ligand substitution) (or before being ejected from the nozzle) may include a non-polar organic ligand (360). In the process of substituting the non-polar organic ligand (360) with the polar organic ligand (360), a polar substance (370) may be used. In various embodiments, the method of imparting polarity to the ligand (360) may vary. For example, at least one of a method of extracting the quantum dot and then substituting a portion of the chemical structure of the ligand (360) with the polar substance (370), a method of substituting the entire ligand (360) with the polar substance (370), and a method of adding the polar substance (370) to the ligand (360) may be used. Through this, the quantum dot (300) including the substituted ligand (360) can be imparted with electrical polarity (e.g., negative or positive charge).

[0060] Quantum dots (300) may include quantum dots of a first color, quantum dots of a second color, and quantum dots of a third color. The wavelength of light emitted by the quantum dots (300) may vary depending on the size of the particles. For example, as the size of the quantum dots (300) decreases, the band gap of the quantum dots increases, allowing them to emit light of a shorter wavelength. For example, when the size of the quantum dots of the second color is formed to be larger than that of the quantum dots of the first color and smaller than that of the quantum dots of the third color, the wavelength of light emitted by the quantum dots of the first color may be the shortest, and the wavelength of light emitted by the quantum dots of the third color may be the longest. For example, the quantum dots of the first color, the quantum dots of the second color, and the quantum dots of the third color may emit blue, green, and red light, respectively.

[0061] Below, the descriptions provided regarding quantum dots (300) can be applied substantially identically or similarly to quantum dots of a first color, quantum dots of a second color, and quantum dots of a third color.

[0062] FIG. 3D is a drawing for explaining a method for manufacturing ink for printing a light-emitting layer of a display according to one embodiment.

[0063] Referring to FIGS. 3c and 3d, in one embodiment, a luminescent solution (500) can be formed by substituting a ligand (360) of a quantum dot (300) with a polar organic substance and mixing the quantum dot (300) including the substituted ligand (360) with a solvent (400).

[0064] The quantum dot (300) substituted with the ligand (360) can be mixed with a solvent (400) to form a luminescent solution (500). The solvent (400) can include a compatible material so that it can be easily mixed with the quantum dot (300). For example, the solvent (400) can be formed of a polar solvent (e.g., water) or various organic solvents. For example, the solvent (400) can include any one of acetone, ethanol, propylene glycol methyl ether acetate (PGMEA), ethylene glycol, isopropyl alcohol (2-propanol), and acetonitrile. The solvent (400) may have conductivity so that the quantum dots (300) can be uniformly dispersed within the luminescent solution (500) during the process of being mixed with the quantum dots (300) to form the luminescent solution (500). For example, the solvent (400) may have an electrical conductivity of a specified value (e.g., 10 -7 It may contain substances that are set to be measured in S / m (S is Siemens, m is meter) or more.

[0065] The luminescent solution (500) may contain a certain ratio of quantum dots (300). For example, the luminescent solution (500) may contain quantum dots (300) at a concentration of 0.01 to 5 wt% (weight percent). The luminescent solution (500) may not contain any other substances other than the quantum dots (300) and the solvent (400), and may have low viscosity characteristics like a pure solvent. Through this, the luminescent solution (500) may have relatively superior luminescent efficiency compared to a case where the luminescent solution (500) contains other compounds other than the quantum dots (300) and the solvent (400).

[0066] FIG. 3e is a drawing for explaining the characteristics of quantum dots constituting the light-emitting layer of a display according to one embodiment.

[0067] Referring to FIGS. 1b, 3c, 3d, and 3e, in one embodiment, the quantum dot (300) may have a zeta potential when dispersed in a solvent (400, for example, water or ethanol). The quantum dot (300) may have a zeta potential by including a ligand (360) substituted with a polar material (370) at the outermost layer. In one example, the zeta potential of the quantum dot (300) mixed in the solvent (400) may be measured in a range of -10 mV or less and +10 mV or more. Accordingly, as illustrated in FIG. 3e, in one embodiment, when the quantum dot (300) is formed to have a negative polarity, it may move (for example, in the direction of the arrow) toward a layer having a positive polarity (for example, the hole transport layer (140), the substrate (110), or the first electrode layer (130)) in an electric field. Accordingly, different quantum dots (300) can be uniformly dispersed without clumping together in the light-emitting solution (500), and can be uniformly printed on the hole transport layer (140) through a nozzle (e.g., nozzle (205) of FIG. 4c) to form a light-emitting layer (150).

[0068] FIGS. 4a, 4b, 4c, and 4d are drawings for explaining a manufacturing process of a light-emitting layer of a display according to one embodiment.

[0069] Referring to FIGS. 1B, 4A, 4B, 4C, and 4D, in one embodiment, a substrate (202) (e.g., substrate (110) of FIG. 1B) having a transistor layer (120), a first electrode layer (130), and a hole transport layer (140) formed thereon may be provided. The substrate (202) may be placed on a holder (203). A fiducial mark (204) may be formed on the substrate (202). The fiducial mark (204) may be used to identify a position of the substrate (202) (e.g., a position on at least one of the x-axis, the y-axis, and the z-axis). For example, an imaging device such as a vision camera may recognize the fiducial mark (204, e.g., fiducial mark) to ensure that the substrate (202) is aligned at the correct position. After the substrate (202) is aligned on the holder (203) at a position suitable for printing the light-emitting layer (150), ink (e.g., the light-emitting solution (500) of FIG. 3D) can be jetted onto the substrate (202) through an electrohydrodynamic (EHD) process. The ink forming the light-emitting layer (150) can be jetted onto the substrate (202) through the nozzle (205) of the inkjet unit. During this process, the nozzle (205) moves in a first direction (e.g., the -x-axis direction), and the ink can be continuously jetted in the first direction (e.g., the -x-axis direction). Therefore, in one embodiment, the light-emitting layer (150) can be printed on the substrate (202) in a continuous form parallel to the movement direction of the nozzle (205). For example, a first color light-emitting layer (151), a second color light-emitting layer (152), and a third color light-emitting layer (153) can be sequentially printed along a first direction (e.g., -x-axis direction). The substrate (202) on which the light-emitting layer (150) is formed can be separated from the holder (203), and the display (100) can be completed by sequentially forming an electron transport layer (160), a second electrode layer (170), an encapsulating layer (180), and a protective layer (190) on the light-emitting layer (150). Details regarding a method for forming the light-emitting layer (150) will be described later with reference to FIGS. 5A to 6C.

[0070] FIGS. 5A and 5B are drawings for explaining a method of printing a light-emitting layer of a display according to one embodiment.

[0071] Referring to FIGS. 1B, 4C, 5A, and 5B, in one embodiment, the light-emitting layer (150) may be formed on the hole transport layer (140). However, for convenience of explanation, the following description will briefly describe that the light-emitting layer (150) formed with a light-emitting solution (500) containing quantum dots (300) and a solvent (400) is printed (or attached) on the first electrode layer (130). Those skilled in the art will be able to fully understand that the light-emitting layer (150) formed with a light-emitting solution (500) containing quantum dots (300) and a solvent (400) is disposed on the hole transport layer (140) disposed on the first electrode layer (130).

[0072] The light-emitting layer (150) can be formed through an electrohydrodynamic (EHD) process. The EHD process can form a continuous ink line by using a constant air pressure and electric field applied to the nozzle (205) of the inkjet unit. For example, a first voltage can be applied to the nozzle (205). A second voltage can be applied to the holder (203, or a conductive film on the holder (203)) and / or the first electrode layer (130). For example, the second voltage can be applied to the holder (203) on which the first substrate (202) is mounted, thereby inducing the second voltage to the hole transport layer (140) through the first substrate (202). Alternatively, as an example, a second voltage may be applied to the first electrode layer (130), thereby inducing the second voltage to the hole transport layer (140) through the first electrode layer (130).

[0073] The first voltage of the nozzle (205) may be a direct current voltage or an alternating current voltage. In one embodiment, when the first voltage of the nozzle (205) is a direct current voltage, the luminescent solution (500) can be continuously printed while maintaining a designated potential difference with the second voltage of the first electrode layer (130). In contrast, when the first voltage of the nozzle (205) is an alternating current voltage, the potential difference with the second voltage of the first electrode layer (130) can be varied. The electric field formed by the first voltage and the second voltage can be set to have a certain range. For example, the electric field is 1x10 9 V / m (V is volt, m is meter) to 2x10 5 It can be set to have a range within V / m. The quantum dot (300) can be electrically polarized by a ligand (e.g., ligand (360) of FIG. 3c) substituted with a polar material (e.g., polar material (370) of FIG. 3c), and can move along an electric field formed by a potential difference between the nozzle (205) and the first electrode layer (130).

[0074] The length (e.g., L3) of the light-emitting solution (500) printed on the first electrode layer (130) in the second direction (e.g., y-axis direction) may be substantially the same as or longer than the length (e.g., L2) of the first electrode layer (130) in the second direction (e.g., y-axis direction). For example, immediately after the light-emitting solution (500) is printed on the first electrode layer (130), since the solvent (400) occupies the space on the transistor layer (120) in addition to the quantum dots (300) attached onto the first electrode layer (130), the length (e.g., L3) of the light-emitting solution (500) in the second direction (e.g., y-axis direction) may be formed to be longer than the length (e.g., L2) of the first electrode layer (130) in the second direction (e.g., y-axis direction). However, the solvent (400) may be removed after printing the light-emitting solution (500) through drying or an additional process (e.g., after baking). Accordingly, only the quantum dots (300) may remain on the first electrode layer (130), and the second direction (e.g., y-axis direction) length of the light-emitting layer (150) including the quantum dots (300) may be formed to be substantially the same as the second direction (e.g., y-axis direction) length (e.g., L2) of the first electrode layer (130). That is, the light-emitting layer (150) may not include any other material other than the quantum dots (300). The light-emitting layer (150) may be formed as a thin and uniform film in which the quantum dots (300) are laminated in one or two layers in the +z-axis direction.

[0075] The nozzle (205) can print the luminescent solution (500) in a first direction (e.g., -x-axis direction). The quantum dots (300) forming the luminescent solution (500) can be arranged long in the first direction (e.g., -x-axis direction), which is the movement direction of the nozzle, on the first electrode layer (130). The quantum dots (300) forming the luminescent solution (500) can be arranged longer in the first direction (e.g., -x-axis direction) than in the second direction (e.g., y-axis direction).

[0076] FIGS. 6A, 6B, and 6C are drawings for explaining a method of stacking quantum dots in a process of printing a light-emitting layer of a display according to one embodiment.

[0077] Referring to FIGS. 5A, 6A, 6B, and 6C, in one embodiment, a second voltage may be applied to the first electrode layer (130), and a first voltage may be applied to the nozzle (205). The second voltage applied to the first electrode layer (130) may have a higher potential than the first voltage applied to the nozzle (205). The first electrode layer (130) may be positively charged, and the quantum dots (300) may be negatively charged. The first electrode layer (130) may have a positive polarity, and the quantum dots (300) may have a negative polarity. In this case, the quantum dots (300) having a negative polarity may be jetted from the nozzle (205) and at the same time receive a strong electric force toward the first electrode layer (130) having the opposite polarity, that is, a positive polarity.

[0078] In one embodiment, a second voltage may be applied to the first electrode layer (130), and a first voltage may be applied to the nozzle (205). The second voltage applied to the first electrode layer may have a lower potential than the first voltage applied to the nozzle (205). The first electrode layer (130) may be charged with a negative charge, and the quantum dots (300) may have a positive charge. The first electrode layer (130) may have a negative polarity, and the quantum dots (300) may have a positive polarity. In this case, the quantum dots (300) having a positive polarity may be jetted from the nozzle (205) and at the same time receive a strong electric force toward the first electrode layer (130) having the opposite polarity, that is, the negative polarity.

[0079] A repulsive force may be applied between the quantum dots (300) to be sprayed from the nozzle (205) (or to be printed on the substrate, or to be aligned on the substrate) and the quantum dots (300) already (or first) printed (or aligned) on the first electrode layer (130). An attractive force may be applied between a portion of the first electrode layer (130) exposed between the quantum dots (300) printed on the first electrode layer (130) (or an area where the quantum dots are empty) (e.g., A1) and the quantum dots (300) sprayed from the nozzle (205). Therefore, the quantum dots (300) may first be attached to the empty area (e.g., A1) on the first electrode layer (130) to form a uniform layer.

[0080] As shown in FIG. 6b, according to one embodiment, the quantum dots (300) included in the luminescent solution (500) may be printed in a sequentially stacked multi-layer structure. A plurality of quantum dots (300) may be aligned in a layer structure and then aligned in a layer structure again to be printed in a multi-layer structure. For example, a plurality of quantum dots (300) may be aligned in a virtual first layer close to the first electrode layer (130) and then aligned in a virtual second layer far from the first electrode layer (130). The virtual first layer and the virtual second layer may be formed through at least one (or one or multiple) printing processes. At least a portion of the quantum dots (300) included in the second layer may be ejected from the nozzle (205) later than the quantum dots (300) included in the first layer.

[0081] According to one embodiment, the attraction between a first electrode layer (130) having a first polarity (e.g., positive polarity) and a quantum dot (300) having a second polarity (e.g., negative polarity) may become stronger (weaker) as the separation distance between them becomes closer (farther away). At least some of the plurality of quantum dots (300) may be first aligned closer to the first electrode layer (130) and then aligned further away from the first electrode layer (130).

[0082] According to one embodiment, among the quantum dots (300) included in the second layer, the quantum dots (300) with a later alignment order can form a stronger attractive force with the first electrode layer (130) in the region (e.g., A2) between the quantum dots (300) already aligned in the second layer than on top of the quantum dots (300) already aligned in the second layer. Among the quantum dots (300) included in the second layer, the quantum dots (300) with a later alignment order can be aligned in the empty region (e.g., A2) between the quantum dots (300) already aligned in the second layer even if they are printed on top of the quantum dots (300) already aligned in the second layer.

[0083] FIG. 6c may illustrate, according to one embodiment, a plurality of quantum dots (300) attached to a first electrode layer (130) by an electric field between the nozzle (230) and the first electrode layer (130) to form a uniform multi-layer structure. Accordingly, a light-emitting layer (150) including a plurality of quantum dots (300) may implement a display with excellent uniformity of brightness.

[0084] In various embodiments, the thickness of the light-emitting layer (150) (e.g., thickness in the +z direction) may be formed to be several hundred nm (e.g., 100 nm) or less. For example, the size of the quantum dots (300) constituting the light-emitting layer (150) may be formed to be 5 to 10 nm. When such quantum dots (300) are laminated in one or two layers, the thickness of the light-emitting layer (150) (e.g., thickness in the +z direction) may be formed to be thin, such as 5 to 20 nm, so that the light-emitting efficiency may be excellent.

[0085] In various embodiments, the method of forming a potential difference between the nozzle (205) and the first electrode layer (or substrate (e.g., substrate (202) of FIG. 4A)) (130) is not limited to the above-described example. For example, an electrode having an area corresponding to (e.g., substantially the same as) the substrate (202) may be formed on a stage on which the substrate (202) is mounted, and a second voltage may be applied to the electrode to form a potential difference between the electrode of the stage and the nozzle (205). Alternatively, in one embodiment, the first electrode layer (130) may be formed by applying a second voltage through a signal line included in a transistor layer (e.g., transistor layer (120) of FIG. 1B) to form a potential difference between the first electrode layer (130) and the nozzle (205).

[0086] Figure 7a is a plan view of a first embodiment of the display.

[0087] Figure 7b is a cross-sectional view of a first embodiment of the display.

[0088] FIG. 7A is a drawing showing a display according to a first embodiment when viewed in the +z-axis direction. In FIG. 7A, only some components (e.g., pixel defining layer (625), light-emitting layer (650), and protrusion (654)) are illustrated to help understanding. FIG. 7B is a drawing showing a cross-section of a part of the display according to the first embodiment when cut in the x-axis direction. Referring to FIGS. 7A and 7B, in one embodiment, the display (600) may include a substrate (610), a transistor layer (620), and a light-emitting element (601). As an example, the light-emitting element (601) may include a first electrode layer (630), a hole transport layer (640), a light-emitting layer (650), a protrusion (654), an electron transport layer (660), and a second electrode layer (670).

[0089] In one embodiment, the description provided in relation to the display (100) of FIG. 1B may be applied to the display (600) of FIG. 7B. The description provided in relation to the substrate (110) of FIG. 1B may be applied to the substrate (610) of FIG. 7B. The description provided in relation to the transistor layer (120) of FIG. 1B may be applied to the transistor layer (620) of FIG. 7B. The description provided in relation to the light emitting device (601) of FIG. 7B may be applied to the light emitting device (101) of FIG. 1B. The description provided in relation to the first electrode layer (130) of FIG. 7B may be applied to the first electrode layer (630) of FIG. 7B. The description provided in relation to the hole transport layer (140) of FIG. 1B may be applied to the hole transport layer (640) of FIG. 7B. The description provided in relation to the light-emitting layer (150) of FIG. 1B may be applied to the light-emitting layer (650) of FIG. 7B. The description provided in relation to the electron-transport layer (160) of FIG. 1B may be applied to the electron-transport layer (660) of FIG. 7B. The description provided in relation to the second electrode layer (170) of FIG. 1B may be applied to the second electrode layer (670) of FIG. 7B.

[0090] In one embodiment, the pixel defining film (625) may be disposed between the transistor layer (620) and the hole transport layer (640) in the z-axis direction. In addition, the pixel defining film (625) may be disposed in an area of ​​the transistor layer (620) in the x-axis direction, excluding an area where the first electrode layer (630) is disposed. For example, the pixel defining film (625) may be formed in an area between a plurality of first electrodes included in the first electrode layer (630). The pixel defining film (625) may be formed such that a lower surface (627) in contact with the transistor layer (620) is relatively larger than an upper surface (626) located opposite the lower surface (627). That is, the pixel defining film (625) may include a tapered surface (628) that connects the upper surface (626) and the lower surface (627) and forms a predetermined angle with the x-axis. The x-axis direction length (e.g., L4) of the pixel defining film (625) may be formed to be substantially equal to or greater than the spacing (e.g., D2) between the plurality of first electrodes included in the first electrode layer (630). For example, when the x-axis direction length (e.g., L4) of the pixel defining film (625) is greater than the spacing (e.g., D2) between the plurality of first electrodes included in the first electrode layer (630), the pixel defining film (625) may at least partially contact the first electrode layer (630), and a portion of the pixel defining film (625) may be disposed on the first electrode layer (630). The pixel defining film (625) may be formed of a material such as a metal, a synthetic resin, a synthetic rubber, or a carbon-based organic material. The pixel defining film (625) may prevent electrical short circuiting of the first electrode layer (630). The pixel defining film (625) can prevent adjacent light-emitting layers (650) from mixing by preventing the light-emitting layer (650) from crossing over to adjacent sub-pixels (SP1, SP2, SP3).

[0091] The hole transport layer (640) may be disposed on the pixel defining film (625) and the first electrode layer (630). The hole transport layer (640) may include a portion disposed on the first electrode layer (630) and a remaining portion in contact with (or disposed on) the pixel defining film (625). For example, the hole transport layer (640) may include a portion formed with an x-axis length (e.g., L5) that is substantially the same as or smaller than the x-axis length of each of the plurality of first electrodes included in the first electrode layer (630), and may surround at least a portion except for the lower surface (627) of the pixel defining film (625). Accordingly, the hole transport layer (640) may be formed continuously in the x-axis direction and have a step in the z-axis direction equal to the z-axis height (e.g., H1) of the pixel defining film (625). In the region between and corresponding to the plurality of first electrodes, a substrate (610), a transistor layer (620), a pixel defining film (625), a hole transport layer (640), an electron transport layer (660), and a second electrode layer (670) may be sequentially stacked. The hole transport layer (640) in the region between and corresponding to the plurality of first electrodes may be arranged on a plane higher than the hole transport layer (640) in the region corresponding to each of the plurality of first electrodes.

[0092] In one example, a protrusion (654) may be arranged in a region of the hole transport layer (640) that corresponds to the upper surface (626) furthest from the transistor layer (620) of the pixel defining film (625) (e.g., located in the +z-axis direction). When the protrusion (654) is viewed from above (or above) the protrusion (654), at least a portion of the protrusion (654) may be formed in a ring shape, a circle, a hollow shape, an oval shape, or a polygonal shape. The protrusion (654) may be formed of the same material as the light-emitting layer (650) (e.g., quantum dots (300 of FIG. 6A)). According to one embodiment, the protrusion (654) may appear circular when viewed in the +z-axis direction. For example, the protrusion (654) may have more particles (e.g., quantum dots (300 of FIG. 6A)) accumulated as it gets farther away from the center. Accordingly, the protrusion (654) may be formed such that the height of the edge in the z-axis direction is the highest. For example, the protrusion (654) may be a ring-shaped cone with a raised edge. For example, the protrusion (654) may be formed in a circular or polygonal shape in which the edge surrounding the center is thicker than the center.

[0093] According to one embodiment, the protrusion (654) may be disposed on a pixel defining film (625) disposed between sub-pixels (SP1, SP2, or SP3) that implement the same color. The protrusion (654) may be disposed on a pixel defining film (625) disposed between light-emitting layers (651) of a first color. The protrusion (654) may be disposed on a pixel defining film (625) disposed between light-emitting layers (652) of a second color. The protrusion (654) may be disposed on a pixel defining film (625) disposed between light-emitting layers (653) of a third color.

[0094] The protrusion (654) may not be formed on the pixel defining film (625) disposed between sub-pixels (SP1, SP2, SP3) that implement different colors. The protrusion (654) may not be formed on the pixel defining film (625) disposed between the first color emitting layer (651) and the second color emitting layer (652). The protrusion (654) may not be formed on the pixel defining film (625) disposed between the second color emitting layer (652) and the third color emitting layer (653). The protrusion (654) may not be formed on the pixel defining film (625) disposed between the first color emitting layer (651) and the third color emitting layer (653).

[0095] The light-emitting layer (650) may be provided with a plurality of light-emitting layers spaced apart in a first direction (e.g., -x-axis direction) and a second direction (e.g., y-axis direction). For example, the light-emitting layer (650) may include a first color light-emitting layer (651, applying the first color light-emitting layer (151) of FIG. 1A), a second color light-emitting layer (652, applying the second color light-emitting layer (152) of FIG. 1A), and a third color light-emitting layer (653, applying the third color light-emitting layer (153) of FIG. 1A) spaced apart in a second direction (e.g., y-axis direction). The first color light-emitting layer (651) may again be provided with a plurality of first color light-emitting layers spaced apart in a first direction (e.g., -x-axis direction). In one embodiment, the light-emitting layers spaced apart in a first direction (e.g., the -x-axis direction) may include quantum dots (e.g., the quantum dots (300) of FIG. 6A) that implement the same color. In contrast, the light-emitting layers spaced apart in a second direction (e.g., the y-axis direction) may include quantum dots (e.g., the quantum dots (300) of FIG. 6A) that implement different colors. Each of the light-emitting layers (650) spaced apart in the first direction (e.g., the -x-axis direction) and the second direction (e.g., the y-axis direction) may be formed to be substantially equal to or smaller than the spacing between the pixel defining layers (625). The z-axis thickness of each light-emitting layer (650) may be formed to be substantially equal to or smaller than the z-axis height (e.g., H1) of the pixel defining layer (625) minus the z-axis thickness of the hole transport layer (640).

[0096] In one embodiment, the width in the second direction (e.g., length in the y-axis direction) of the light-emitting layer (650) disposed on the first electrode layer (630) may be formed to be longer than the width in the second direction (e.g., length in the y-axis direction) of the protrusion (654) disposed on the pixel defining film (625).

[0097] With respect to the plurality of pixels (PXL) of the display (600) and the first sub-pixel (SP1), the second sub-pixel (SP2), and the third sub-pixel (SP3) constituting each pixel (PXL), the description provided with reference to FIG. 1A may be applied substantially identically or similarly.

[0098] FIG. 8a, FIG. 8b, and FIG. 8c are drawings for explaining a method for manufacturing a light-emitting layer of a display according to the first embodiment.

[0099] For convenience of explanation, in FIGS. 8A, 8B, and 8C, the hole transport layer (640) is omitted and only the transistor layer (620), the pixel defining film (625), and the first electrode layer (630) are illustrated. Those skilled in the art will readily understand that the light-emitting layer (650) is printed on the hole transport layer (640) disposed on the first electrode layer (630) and the pixel defining film (625).

[0100] Fig. 8a <801> silver <802> It is a cross-section cut along the x-axis of a part of Fig. 8b. <803> silver <804> It is a cross-section cut along the x-axis, and Fig. 8c <805> Is <806> It is a cross-section of a part cut along the x-axis.

[0101] Referring to FIGS. 3D, 4A, 7A, 7B, 8A, 8B, and 8C, in one embodiment, a light-emitting layer (650) can be completed by printing a light-emitting solution (e.g., light-emitting solution (500) of FIG. 3D) on a pixel defining film (625) and a first electrode layer (630) and then drying a solvent (e.g., solvent (400) of FIG. 3D).

[0102] Referring to FIG. 8A, in one embodiment, a substrate (e.g., substrate (202) of FIG. 4A) may be provided on which a transistor layer (620), a first electrode layer (630), and a pixel defining film (625) are sequentially formed. When the substrate (202) is viewed in the +z-axis direction, a plurality of first electrodes provided on the first electrode layer (630) are arranged in a grid shape, and a pixel defining film (625) may be visible between the plurality of first electrodes.

[0103] Referring to FIG. 8B, in one embodiment, the nozzle (605) may move in a direction parallel to the substrate (202) (e.g., in the -x-axis direction) while spraying the luminescent solution (500) in a direction perpendicular to the substrate (202) (e.g., in the -z-axis direction). Accordingly, the luminescent solution (500) may be continuously printed in a first direction (e.g., in the -x-axis direction) from one side of the substrate (202) to the other side according to the movement of the nozzle (605). When the nozzle (605) completes printing once in the first direction (e.g., in the -x-axis direction), the nozzle (605) may move in a second direction (e.g., in the y-axis direction) to print the luminescent solution (500) in a third direction (e.g., in the +x-axis direction) from the other side of the substrate (202) to one side again. Thereafter, the nozzle (605) can move in a second direction (e.g., y-axis direction) to print the luminescent solution (500) in the first direction (-x-axis direction) from one side of the substrate (202) to the other side. Therefore, when printing the luminescent layer (650) through one nozzle (605), the nozzle (605) can be moved in a zigzag shape on the substrate (202), and the same process can be repeated several times.

[0104] According to one embodiment, a first color luminescent solution (500) may be printed at least once from one side of the substrate (202) to the other side through a plurality of nozzles (605), and then the plurality of nozzles (605) may move in a second direction (e.g., in the y-axis direction). Thereafter, the plurality of nozzles (605) may print a second color luminescent solution (500) at least once from the other side of the substrate (202) to one side. After printing the second color luminescent solution (500) at least once, the plurality of nozzles (605) may move in the second direction (e.g., in the y-axis direction) and then print a third color luminescent solution (500) at least once from one side of the substrate (202) to the other side. In this process, the luminescent solution (500) may also be printed on the pixel defining film (625). In one embodiment, each of the light-emitting layers (651, 652, 653) can be formed by being printed in a first direction (e.g., -x-axis direction) by a nozzle (605) containing different light-emitting solutions.

[0105] Referring to FIG. 8c, in one embodiment, after printing the luminescent solution (500), only the quantum dots (300) included in the luminescent solution (500) may remain on the substrate (202) by drying (e.g., natural drying) the solvent (400) to form a luminescent layer (650).

[0106] The light-emitting layer (650) may include a first color light-emitting layer (651), a second color light-emitting layer (652), and a third color light-emitting layer (653) spaced apart in a second direction (e.g., y-axis direction). That is, each of the first color light-emitting layer (651), the second color light-emitting layer (652), and the third color light-emitting layer (653) may have a continuous shape from one side of the substrate (202) to the other side. Accordingly, each of the first color light-emitting layer (651), the second color light-emitting layer (652), and the third color light-emitting layer (653) may be formed in a vertical stripe pattern when viewed in the +z-axis direction. In one embodiment, the first color light-emitting layer (651), the second color light-emitting layer (652), and the third color light-emitting layer (653) may implement green, red, and blue, respectively.

[0107] The quantum dots (300) remaining on the pixel defining layer (625) may form protrusions (654). For example, the shape of the protrusions (654) may be formed regularly and uniformly across the entire substrate (202). The quantum dots (300) included in the protrusions (654) may not be positioned on the first electrode layer (630), and thus no current may flow or insufficient current may flow to emit light. Accordingly, light emission does not occur in the protrusions (654), and the light emission area of ​​the display (600) may correspond to the light emission layer (650) excluding the protrusions (654). That is, the light emission area of ​​the display (600) may appear substantially the same as the shape illustrated in FIG. 1A. For example, the sub-pixels (SP1, SP2, SP3) of the display (600) may not be defined by the printing shape of the quantum dots (300). For example, the sub-pixels (SP1, SP2, SP3) of the display (600) can be defined and implemented by the shape of the first electrode layer (630).

[0108] Figure 9a is a plan view of a second embodiment of the display.

[0109] Figure 9b is a cross-sectional view of a second embodiment of the display.

[0110] Fig. 9a is a drawing showing a top view of a display according to a second embodiment. In Fig. 9a, only some components (e.g., a first electrode layer (730), a hole transport layer (740), and a light-emitting layer (750)) are shown to aid understanding. Fig. 9b is a drawing showing a cross-section of a part of a display according to the second embodiment cut in the x-axis direction.

[0111] Referring to FIGS. 9A and 9B, in one embodiment, a display device (700) may include a substrate (710), a transistor layer (720), and a light-emitting element (701). As an example, the light-emitting element (701) may include a first electrode layer (730), a hole transport layer (740), a light-emitting layer (750), an electron transport layer (760), and a second electrode layer (770).

[0112] In one embodiment, the description provided in relation to the display (100) of FIG. 1B may be applied to the display (700) of FIG. 9B. The description provided in relation to the substrate (110) of FIG. 1B may be applied to the substrate (710) of FIG. 9B. The description provided in relation to the transistor layer (120) of FIG. 1B may be applied to the transistor layer (720) of FIG. 9B. The description provided in relation to the light emitting device (701) of FIG. 9B may be applied to the light emitting device (101) of FIG. 1B. The description provided in relation to the first electrode layer (130) of FIG. 9B may be applied to the first electrode layer (730) of FIG. 9B. The description provided in relation to the hole transport layer (140) of FIG. 1B may be applied to the hole transport layer (740) of FIG. 9B. The description provided in relation to the light-emitting layer (150) of FIG. 1B may be applied to the light-emitting layer (750) of FIG. 9B. The light-emitting layer (750) may have a multi-layer structure in which quantum dots (300) are laminated on at least one side. The description provided in relation to the electron transport layer (160) of FIG. 1B may be applied to the electron transport layer (760) of FIG. 9B. The description provided in relation to the second electrode layer (170) of FIG. 1B may be applied to the second electrode layer (770) of FIG. 9B.

[0113] In one embodiment, a light-emitting layer (750) may be disposed between a hole transport layer (740) and an electron transport layer (760) in a region corresponding to each of a plurality of first electrodes provided in the first electrode layer (730). A light-emitting layer (750) may be disposed between a hole transport layer (740) and an electron transport layer (760) in a region corresponding to and between the plurality of first electrodes. In a region corresponding to and between the plurality of first electrodes, a substrate (710), a transistor layer (720), a hole transport layer (740), a light-emitting layer (750), an electron transport layer (760), and a second electrode layer (770) may be sequentially stacked without a separate pixel-defining layer (e.g., a pixel-defining layer (625) of FIG. 7B). The hole transport layer (740) in the region corresponding to the plurality of first electrodes may be arranged on a plane that is the same as or lower than the hole transport layer (740) in the region corresponding to each of the plurality of first electrodes.

[0114] The light-emitting layer (750) may be provided with a plurality of light-emitting layers spaced apart in a second direction (e.g., in the y-axis direction). For example, the light-emitting layer (750) may include a light-emitting layer of a first color (751, applying the light-emitting layer of the first color (151) of FIG. 1A), a light-emitting layer of a second color (752, applying the light-emitting layer of the second color (152) of FIG. 1A), and a light-emitting layer of a third color (753, applying the light-emitting layer of the third color (153) of FIG. 1A) spaced apart in a second direction (e.g., in the y-axis direction). In one embodiment, each of the light-emitting layers (751, 752, 753) extending in the first direction (e.g., in the -x-axis direction) may include quantum dots (300) that implement different colors. For example, the light-emitting layer (751) of the first color can implement green, the light-emitting layer (752) of the second color can implement red, and the light-emitting layer (753) of the third color can implement blue. The light-emitting layer (750) can include a wider area than the area corresponding to the area of ​​the first electrode layer (730). For example, the light-emitting layer (750) can be formed to be longer than the sum of the lengths of the first direction (e.g., -x-axis direction) of the plurality of first electrodes provided on the first electrode layer (730) in the first direction (e.g., -x-axis direction). In one example, the light-emitting layer (750) can be formed to have a length in the second direction (e.g., y-axis direction) that is substantially the same as or greater than the lengths of the plurality of first electrodes in the second direction (e.g., y-axis direction). That is, the second direction (e.g., y-axis direction) length (e.g., W1) of each light-emitting layer (751, 752, 753) may be substantially equal to or greater than the second direction (e.g., y-axis direction) length (e.g., W3) of each of the plurality of first electrodes.

[0115] According to one embodiment, the light-emitting layer (750) may be disposed on a region on a plurality of first electrodes provided in the first electrode layer (730) and also on a region between the plurality of first electrodes. The width (e.g., length in the y-axis direction) of the light-emitting layer (750) disposed on the plurality of first electrodes and the width (e.g., length in the y-axis direction) of the light-emitting layer (750) disposed between the plurality of first electrodes may be formed to be substantially the same (or constant). On the plurality of first electrodes, the quantum dots (300) may be laminated with a uniform thickness (e.g., length in the z-axis direction). Similarly, between the plurality of first electrodes, the quantum dots (300) may be laminated with a uniform thickness (e.g., length in the z-axis direction). With respect to the plurality of pixels (PXL) of the display (700) and the first sub-pixel (SP1), the second sub-pixel (SP2), and the third sub-pixel (SP3) constituting each pixel (PXL), the description provided with reference to FIGS. 1A and 1B may be applied substantially identically or similarly.

[0116] FIG. 10a, FIG. 10b, and FIG. 10c are drawings for explaining a method for manufacturing a light-emitting layer of a display according to a second embodiment.

[0117] Fig. 10a <1001> silver <1002> It is a cross-section cut along the x-axis, and Fig. 10b <1003> silver <1004> It is a cross-section cut along the x-axis, and Fig. 10c <1005> Is <1006> It is a cross-section of a part cut along the x-axis. <1002> , <1004> , and <1006> The silver indicates an area where a plurality of first electrodes are arranged in the first electrode layer (730) of the hole transport layer (740).

[0118] Referring to FIGS. 3D, 4A, 9A, 9B, 10A, 10B, and 10C, in one embodiment, a light-emitting layer (750) can be completed by printing a light-emitting solution (e.g., light-emitting solution (500) of FIG. 3D) on a hole transport layer (740) and then drying a solvent (e.g., solvent (400) of FIG. 3D).

[0119] Referring to FIG. 10A, in one embodiment, a substrate (e.g., substrate (202) of FIG. 4A) may be provided on which a transistor layer (720), a first electrode layer (730), and a hole transport layer (740) are sequentially formed. A plurality of first electrodes provided on the first electrode layer (730) may be arranged in a grid shape spaced apart in a first direction (e.g., -x-axis direction) and a second direction (e.g., y-axis direction).

[0120] Referring to FIG. 10b, in one embodiment, the nozzle (705) can move in a direction parallel to the substrate (202) (e.g., in the -x-axis direction) while spraying the luminescent solution (500) in a direction perpendicular to the substrate (202) (e.g., in the -z-axis direction). Accordingly, the luminescent solution (500) can be continuously printed in a first direction (e.g., in the -x-axis direction) from one side of the substrate (202) to the other side according to the movement of the nozzle (705). When the nozzle (705) completes printing once in the first direction (e.g., in the -x-axis direction), the nozzle (705) can move in a second direction (e.g., in the y-axis direction) to print the luminescent solution (500) in a third direction (e.g., in the +x-axis direction) from the other side of the substrate (202) to one side again. Thereafter, the nozzle (705) can move in a second direction (e.g., y-axis direction) to print the luminescent solution (500) in the first direction (-x-axis direction) from one side of the substrate (202) to the other side. Therefore, when printing the luminescent layer (750) through one nozzle (705), the nozzle (705) can be moved in a zigzag shape on the substrate (202), and the same process can be repeated several times.

[0121] According to one embodiment, a first color luminescent solution (500) may be printed at least once from one side of the substrate (202) to the other side through a plurality of nozzles (705), and then the plurality of nozzles (705) may move in a second direction (e.g., in the y-axis direction). Thereafter, the plurality of nozzles (705) may print a second color luminescent solution (500) at least once from the other side of the substrate (202) to one side. After printing the second color luminescent solution (500) at least once, the plurality of nozzles (705) may move in a second direction (e.g., in the y-axis direction) and then print a third color luminescent solution (500) at least once from one side of the substrate (202) to the other side. In one embodiment, each of the light-emitting layers (751, 752, 753) can be formed by being printed in a first direction (e.g., -x-axis direction) by a nozzle (705) containing different light-emitting solutions.

[0122] Referring to FIG. 10c, in one embodiment, after printing the luminescent solution (500), only the quantum dots (300) included in the luminescent solution (500) may remain on the third substrate (702) by drying (e.g., natural drying) the solvent (400) to form a luminescent layer (750).

[0123] The light-emitting layer (750) may include a first color light-emitting layer (751), a second color light-emitting layer (752), and a third color light-emitting layer (753) spaced apart in a second direction (e.g., y-axis direction). Each of the light-emitting layers (751, 752, 753) may be formed by being printed in the first direction (e.g., -x-axis direction) by a nozzle (705) containing different light-emitting solutions. That is, each of the light-emitting layers (751, 752, 753) may have a continuous shape from one side of the substrate (202) to the other side. Accordingly, the light-emitting layer (750) may be formed in a vertical stripe pattern when viewed in the +z-axis direction. In one embodiment, the first color light-emitting layer (751), the second color light-emitting layer (752), and the third color light-emitting layer (753) may implement green, red, and blue, respectively. Details regarding the light-emitting area of ​​the display (700) are described later in FIG. 11.

[0124] FIG. 11 is a drawing showing a light-emitting area of ​​a light-emitting layer according to one embodiment.

[0125] Referring to FIGS. 4A, 9A to 10C, and 11, in one embodiment, the light-emitting layer (750) may be formed continuously from one side of the substrate (202) to the other side in a first direction (e.g., in the -x-axis direction). The light-emitting layer (750) may be disposed on first regions (e.g., R1) on which the first electrode layer (730) is formed on the substrate (202) and second regions (e.g., R2) between the first regions (e.g., R1). Accordingly, the light-emitting layer (750) may be in the form of being linearly printed in the first direction (e.g., in the -x-axis direction) on the first regions (e.g., R1) and the second regions (e.g., R2). In the third regions (e.g., R3) of the light-emitting layer (750) disposed on the first regions (e.g., R1), holes injected from the first electrode layer (730) into the hole transport layer (740) can be transported to the light-emitting layer (750), and electrons injected from the second electrode layer (770) into the electron transport layer (760) can be transported to the light-emitting layer (750). Therefore, excitons formed by combining electrons and holes transported to the light-emitting layer (750) can emit light. That is, quantum dots (300) disposed in the third regions (e.g., R3) of the light-emitting layer (750) can emit light by forming excitons. In contrast, in the fourth region (e.g., R4) of the light-emitting layer (750) disposed on the second region (e.g., R2), holes may not be transported from the first electrode layer (730), and thus combination with electrons transported from the second electrode layer (770) may be impossible. For example, within the light-emitting layer (750), current may flow along the closest path from the first electrode layer (730) toward the second electrode layer (770), and in the quantum dot (300) located in the region (e.g., R4) that does not correspond to the region on the first electrode layer (730), no current may flow, or only a very small current that is not sufficient for the quantum dot (300) to emit light may flow. Therefore, the quantum dot (300) disposed on the fourth region (e.g., R4) of the light-emitting layer (750) may not emit light because excitons are not formed.

[0126] Accordingly, the sub-pixels (e.g., SP1, SP2, SP3) of the display (700) can be distinguished by the shape of the first electrode layer (730). For example, the third regions (e.g., R3) of the light-emitting layer (750) disposed on the first electrode layer (730) can be light-emitting regions, and the other fourth regions (e.g., R4) can be non-light-emitting regions. Accordingly, the light-emitting regions of the display (700) can appear in a grid shape spaced apart in the first direction (e.g., -x-axis direction) and the second direction (e.g., y-axis direction). The first electrode layer (730) can be provided with a plurality of first electrodes, and the light-emitting regions of the display (700) can be formed in a shape substantially identical to the shape of the plurality of first electrodes. In addition, according to one example, each of the sub-pixels (e.g., SP1, SP2, SP3) of the display (700) can have a shape substantially identical to the shape of the plurality of first electrodes.

[0127] Referring to FIG. 7B, the display (700) can define sub-pixels (e.g., SP1, SP2, SP3) and pixels (PXL) without a pixel defining layer (e.g., pixel defining layer 625 of FIG. 7B). For example, a light-emitting layer (750) distinguished for each sub-pixel (e.g., SP1, SP2, SP3) can be formed without a pixel defining layer (625) by an electrophoretic electrohydrodynamic (EHD) process that combines an electrohydrodynamic (EHD) process and an electrophoresis process. For example, after the quantum dot (300) is substituted to have an electric polarity, when an electric field is formed according to the potential difference between the nozzle (705) and the substrate (202), the quantum dot (300) can be quickly attached to the substrate (202) along the electric field. An attractive force (e.g., van der Waals force) may be applied between the quantum dots (300) attached to the substrate (202) and the solvent (e.g., the solvent (400) of FIG. 3D), and the luminescent solution (500) including the quantum dots (300) and the solvent (400) may maintain a straight-line printed form without randomly spreading on the substrate (202). When the display (700) is configured without the pixel defining film (625), the phenomenon of the optical performance of the display (700) being deteriorated by organic substances remaining during the formation of the pixel defining film (625) can be prevented.

[0128] Figure 12 is a cross-sectional view of a third embodiment of the display.

[0129] FIG. 12 is a cross-sectional view showing a portion of a display cut in the x-axis direction according to the third embodiment.

[0130] Referring to FIG. 12, in one embodiment, the display (800) may include a substrate (810), a transistor layer (820), and a light-emitting element (801). For example, the light-emitting element (801) may include a first electrode layer (830), a hole transport layer (840), a light-emitting layer (850), an electron transport layer (860), and a second electrode layer (870). According to one example, the surface of the display (800) may be substantially the same as the shape illustrated in FIG. 1A.

[0131] In one embodiment, the description provided with respect to the display (100) of FIG. 12 may be applied to the display (800) of FIG. 12. The description provided with respect to the substrate (110) of FIG. 12 may be applied to the substrate (810) of FIG. 12. The description provided with respect to the transistor layer (120) of FIG. 12 may be applied to the transistor layer (820) of FIG. 12. The description provided with respect to the light emitting device (801) of FIG. 12 may be applied to the light emitting device (101) of FIG. 12. The description provided with respect to the first electrode layer (130) of FIG. 12 may be applied to the first electrode layer (830) of FIG. 12. The description provided with respect to the hole transport layer (140) of FIG. 12 may be applied to the hole transport layer (840) of FIG. 12. The description provided in relation to the light-emitting layer (150) of FIG. 1b may be applied to the light-emitting layer (850) of FIG. 12. The light-emitting layer (850) may have a multi-layer structure in which quantum dots (300) are laminated on at least one side. The description provided in relation to the electron transport layer (160) of FIG. 1b may be applied to the electron transport layer (860) of FIG. 12. The description provided in relation to the second electrode layer (170) of FIG. 1b may be applied to the second electrode layer (870) of FIG. 12.

[0132] In one embodiment, a light-emitting layer (850) may be disposed between a hole transport layer (840) and an electron transport layer (860) in a region corresponding to each of a plurality of first electrodes provided in the first electrode layer (830). In a region corresponding to each of the plurality of first electrodes, the hole transport layer (840) and the electron transport layer (860) may be in direct contact. In a region corresponding to each of the plurality of first electrodes, a substrate (810), a transistor layer (820), a hole transport layer (840), an electron transport layer (860), and a second electrode (870) may be sequentially stacked without a separate pixel defining layer (e.g., a pixel defining layer (625) of FIG. 7B). The hole transport layer (840) in a region corresponding to each of the plurality of first electrodes may be disposed on a plane that is the same as or lower than the hole transport layer (840) in a region corresponding to each of the plurality of first electrodes.

[0133] FIG. 13a, FIG. 13b, and FIG. 13c are drawings for explaining a method for manufacturing a light-emitting layer of a display according to a third embodiment.

[0134] Fig. 13a <1301> silver <1302> It is a cross-section cut along the x-axis, and Fig. 13b <1303> silver <1304> It is a cross-section cut along the x-axis, and Fig. 13c <1305> Is <1306> It is a cross-section of a part cut along the x-axis. <1302> , <1304> , and <1306> It indicates an area where a plurality of first electrodes are arranged in the first electrode layer (830) of the hole transport layer (840).

[0135] Referring to FIGS. 3D, 4A, 12, 13A, 13B, and 13C, in one embodiment, a light-emitting layer (850) can be completed by printing a light-emitting solution (e.g., light-emitting solution (500) of FIG. 3D) on a hole transport layer (840) and then drying a solvent (e.g., solvent (400) of FIG. 3D).

[0136] Referring to FIG. 13A, in one embodiment, a substrate (e.g., substrate (202) of FIG. 4A) may be provided on which a transistor layer (820), a first electrode layer (830), and a hole transport layer (840) are sequentially formed. A plurality of first electrodes provided on the first electrode layer (830) may be arranged in a grid shape spaced apart in a first direction (e.g., -x-axis direction) and a second direction (e.g., y-axis direction).

[0137] Referring to FIG. 13B, in one embodiment, the nozzle (805) may move in a direction parallel to the substrate (202) (e.g., in the -x-axis direction) while spraying the luminescent solution (500) in a direction perpendicular to the substrate (202) (e.g., in the -z-axis direction). Accordingly, the luminescent solution (500) may be continuously printed in a first direction (e.g., in the -x-axis direction) from one side of the substrate (202) to the other side according to the movement of the nozzle (805). When the nozzle (805) completes printing once in the first direction (e.g., in the -x-axis direction), the nozzle (805) may move in a second direction (e.g., in the y-axis direction) to print the luminescent solution (500) in a third direction (e.g., in the +x-axis direction) from the other side of the substrate (202) to one side again. Thereafter, the nozzle (805) can move in a second direction (e.g., y-axis direction) to print the luminescent solution (500) in the first direction (-x-axis direction) from one side of the substrate (202) to the other side. Therefore, when printing the luminescent layer (850) through one nozzle (805), the nozzle (805) can be moved in a zigzag shape on the substrate (202), and the same process can be repeated several times.

[0138] According to one embodiment, a first color luminescent solution (500) may be printed at least once from one side of the substrate (202) to the other side through a plurality of nozzles (805), and then the plurality of nozzles (805) may move in a second direction (e.g., in the y-axis direction). Thereafter, the plurality of nozzles (805) may print a second color luminescent solution (500) at least once from the other side of the substrate (202) to one side. After printing the second color luminescent solution (500) at least once, the plurality of nozzles (805) may move in a second direction (e.g., in the y-axis direction) and then print a third color luminescent solution (500) at least once from one side of the substrate (202) to the other side. In one embodiment, each of the light-emitting layers (851, 852, 853) can be formed by being printed in a first direction (e.g., -x-axis direction) by a nozzle (805) containing different light-emitting solutions.

[0139] During the printing process of the luminescent solution (500), an AC voltage may be applied to at least one of the nozzle (805) and the substrate (202). For example, an AC voltage may be applied to the nozzle (805) and a DC voltage may be applied to the substrate (202). For example, a DC voltage may be applied to the nozzle (805) and an AC voltage may be applied to the substrate (202). For example, an AC voltage may be applied to the nozzle (805) and an AC voltage may be applied to the substrate (802).

[0140] According to one embodiment, the potential difference between the nozzle (805) and the substrate (202) may be periodically changed during the printing process of the luminescent solution (500). For example, the luminescent solution (500) may be formed between the nozzle (805) and the substrate (202) at a first potential difference (V on ) and a second potential difference (V) having a lower potential difference than the first potential difference off ) can be printed on the substrate (202) through the nozzle (805) in a state where the first potential difference (V on) is formed, opposite polarities may be formed on the quantum dots (300) constituting the substrate (202) and the luminescent solution (500), and an electrical attraction may be applied to the quantum dots (300). A second potential difference (V off ) is formed, the same polarity may be formed on the quantum dot (300) constituting the substrate (202) and the luminescent solution (500), and an electrical repulsive force may be applied to the quantum dot (300). Or, in one embodiment, a second potential difference (V off ) may be set so that an electrical attraction that is not sufficient to attach (or adhere, fix) the quantum dot (300) to the substrate (202) is applied even if opposite polarities are formed on the quantum dot (300) constituting the substrate (202) and the luminescent solution (500).

[0141] According to one embodiment, the first potential difference (V on ) are strongly attached to the substrate (202) by a strong electric attraction, while the quantum dots (300) attached to the substrate (202) by a second potential difference (V off ) attached to the substrate (202) can be weakly attached to or separated from the substrate (202) by weak electrical attraction or repulsion. For example, the first potential difference (V) of the luminescent solution (500) on ) located in the first regions (or, first regions corresponding to the first electrode layer (830)) (e.g., R5) formed by the quantum dots (300) can remain attached on the substrate (202) and the second potential difference (V off ) located in the second regions (or, the second regions corresponding to the pixel definition film (625) of FIG. 7b) (e.g., R6) formed by the quantum dots (300) can be freely positioned from the substrate (202) without being restricted by electrical attraction. Therefore, the first potential difference (V on ) and the second potential difference (V off) and the moving speed of the nozzle (805) (e.g., the printing speed of the luminescent solution (500)), the length (e.g., the length in the x-axis direction) of the first regions (or the first regions corresponding to the first electrode layer (830)) (e.g., R5) and the second regions (or the second regions corresponding to the pixel defining film (625) of FIG. 7b) (e.g., R6) and / or the length (e.g., the length in the x-axis direction) of the sub-pixels (e.g., SP1, SP2, SP3) can be determined.

[0142] Referring to FIG. 13c, in one embodiment, even after the solvent (400) is removed through a drying (e.g., natural drying) process after printing the luminescent solution (500), the quantum dots (300) may remain in the second regions (e.g., R6). Therefore, the luminescent layer (850) may be formed through a cleaning process to remove the quantum dots (300) remaining in the second regions (e.g., R6). That is, the second potential difference (V off ) can be removed by a cleaning process. For example, a second potential difference (V off ) can be separated from the substrate (202) by a spraying method using a volatile solvent or a dipping method using a chemical substance or ultrapure distilled water. Through this, the quantum dots (300) can be attached to the substrate (202) only in the first regions (e.g., R5) formed by the first potential difference (Von), and in the second potential difference (V off ) may not have quantum dots (300) in the second regions (e.g., R6).

[0143] The light-emitting layer (850) may include a first color light-emitting layer (851), a second color light-emitting layer (852), and a third color light-emitting layer (853) spaced apart in a second direction (e.g., y-axis direction). Each of the light-emitting layers (851, 852, 853) may be formed by printing in the first direction (e.g., -x-axis direction) by a nozzle containing different light-emitting solutions. Each of the light-emitting layers (851, 852, 853) may be formed of a plurality of spaced-apart light-emitting layers by removing the quantum dots (300) of the second regions (e.g., R6) during a cleaning process. Accordingly, the light-emitting layer (850) may be formed in a horizontal and vertical grid pattern when viewed from the +z-axis direction. In one embodiment, the first color light-emitting layer (851), the second color light-emitting layer (852), and the third color light-emitting layer (853) can each implement green, red, and blue colors.

[0144] According to one example, the light-emitting layer (850) may include a plurality of light-emitting regions separated by second regions (e.g., R6). For example, the light-emitting layer (850) may include a plurality of light-emitting regions spaced apart in a first direction (e.g., -x-axis direction) and a second direction (e.g., y-axis direction) similarly to the plurality of first electrodes of the first electrode layer (830). These plurality of light-emitting regions (or sub-pixels (SP1, SP2, SP3)) may have substantially the same shape as the sub-pixels (e.g., SP1, SP2, SP3) of the light-emitting layer (e.g., light-emitting layer (750) of FIG. 10C) printed while the potential difference between the nozzle (805) and the substrate (202) is fixed (e.g., while a direct current voltage is applied). That is, when forming the light-emitting layer (850), there may be a difference in whether the light-emitting layer (e.g., light-emitting layer (750) of FIG. 10c) is formed continuously in the first direction (e.g., -x-axis direction) when there is no change in the potential difference formed between the nozzle (805) and the substrate (202) (e.g., when a direct current voltage is applied) and when there is a change in the potential difference (e.g., when an alternating current voltage is applied). However, in both cases, the area where light actually emits light and / or the area divided into sub-pixels may appear substantially the same.

[0145] With respect to the plurality of pixels (PXL) of the display (800) and the first sub-pixel (SP1), the second sub-pixel (SP2), and the third sub-pixel (SP3) constituting each pixel (PXL), the description provided with reference to FIG. 1A may be applied substantially identically or similarly.

[0146] Fig. 14 is a cross-sectional view showing a light-blocking member of a display according to the first embodiment.

[0147] Fig. 14 is a drawing showing a form in which a light-blocking member is added to a display (600) with reference to Figs. 7a to 8c. With respect to Fig. 14, the description provided in Figs. 7a to 8c may be applied substantially identically or similarly.

[0148] Referring to FIGS. 7A to 8C and FIG. 14 , in one embodiment, the display (600) may further include a light-blocking member (685). The light-blocking member (685) may overlap the pixel defining film (625) when the display (600) is viewed along the +z-axis. The light-blocking member (685) may be disposed above (or above) (e.g., a portion facing the +z-axis direction) and / or below (or below) (e.g., a portion facing the -z-axis direction) the pixel defining film (625). At least a portion of at least one surface of the light-blocking member (685) may be in contact with the pixel defining film (625). For example, the light-blocking member (685) may be disposed below the lower surface (627) of the pixel defining film (625) that is in contact with the transistor layer (620). In various embodiments, the light-blocking member (685) may have various forms without being limited to the above-described contents and illustrated shapes. For example, the light-blocking member (685) may be arranged to surround one or more surfaces of the pixel-defining film (625). Alternatively, in one embodiment, the display (600) may not be provided with a separate light-blocking member (685), but a pixel-defining film may be formed that includes a light-blocking function so that the pixel-defining film itself can perform the role of the light-blocking member (685).

[0149] Fig. 15a is a cross-sectional view showing a first form of a light-blocking member of a display according to a second embodiment.

[0150] FIG. 15b is a cross-sectional view showing a second form of a light-blocking member of a display according to a second embodiment.

[0151] FIGS. 15A and 15B are drawings showing a form in which a light-blocking member (785) is added to a display (700) with reference to FIGS. 9A to 11. With respect to FIGS. 15A and 15B, the description provided in FIGS. 9A to 11 may be applied substantially identically or similarly.

[0152] Referring to FIGS. 9A to 11 and 15A, in one embodiment, the display (700) may be formed in a bottom-emitting form in which light is emitted in the direction of the substrate (710) (e.g., in the direction of an arrow (or, -z-axis direction)). The display (700) may be completed by forming a light-blocking member (785) on the substrate (710), and forming a transistor layer (720), a first electrode layer (730), a hole transport layer (740), a light-emitting layer (750), an electron transport layer (760), and a second electrode layer (770) above the light-blocking member (785) (e.g., in the +z-axis direction). The light-blocking member (785) may be disposed in regions (e.g., R10) between regions (e.g., R9) on the substrate (710) corresponding to regions where a plurality of first electrodes of the first electrode layer (730) are disposed. Light emitted from the light-emitting layer (750) can be seen to the outside by passing through the substrate (710) while moving along the arrow direction (or, -z-axis direction). When the light-blocking member (785) is formed on the substrate (710), the range of material selection for the substrate (710) is wide, so the efficiency of the process of forming the light-blocking member (785) (e.g., photo resist process) can be improved.

[0153] Referring to FIGS. 9A to 11 and 15B, in one embodiment, the display (700) may further include an encapsulating layer (780) and a protective layer (790).

[0154] The encapsulating layer (780) may be placed on the upper portion (or, above) of the second electrode layer (770) (e.g., the portion facing the +z-axis direction). The encapsulating layer (780) may be formed as a multilayer structure of organic and inorganic films, and may prevent moisture or air from penetrating into the light-emitting element (701).

[0155] The protective layer (790) may be disposed on the upper portion (or, above) of the sealing layer (780) (e.g., the portion facing the +z-axis direction). The protective layer (790) may be formed as a multilayer structure of organic and inorganic films, and may prevent moisture or air from penetrating into the light-emitting element (701). In addition, the protective layer (790) may protect the light-emitting element (701) from external physical impact.

[0156] A plurality of light-blocking members (785) may be disposed between the sealing layer (780) and the protective layer (790). The plurality of light-blocking members (785) may be disposed to be spaced apart from each other in the x-axis direction. For example, the light-blocking members (785) may be disposed to distinguish between each of the sub-pixels (SP1, SP2, SP3) of the display (700). For example, the light-blocking member (785) may be disposed between the first sub-pixel (SP1) region and the second sub-pixel (SP2) region. Accordingly, the light-blocking member (785) may prevent the light emitted from the first sub-pixel (SP1) region and the light emitted from the second sub-pixel (SP2) region from being mixed when light is emitted upward (or in the direction of the arrow) (e.g., in the +z-axis direction) from the light-emitting layer (750). The light-blocking member (785) may be formed of a material such as a metal, a synthetic resin, a synthetic rubber, or a carbon-based organic material. Alternatively, in one example, the shading member (785) may be composed of chromium (Cr), chromium oxide (CrOx), carbon black, or a double film including these.

[0157] In one embodiment, the display (700) may be formed in a front-emitting form in which light is emitted in the direction of the protective layer (790) (or, in the direction of an arrow) (e.g., in the +z-axis direction). The display (700) may be completed by sequentially forming a substrate (710), a transistor layer (720), a first electrode layer (730), an electron transport layer (760) (or a hole transport layer (740)), a light-emitting layer (750), a hole transport layer (740) (or an electron transport layer (760)), a second electrode layer (770), and an encapsulating layer (780), forming a light-blocking member (785) on the encapsulating layer (780), and covering the light-blocking member (785) with the protective layer (790). The light-blocking member (785) may be disposed in regions (e.g., R8) between regions (e.g., R7) where a plurality of first electrodes provided in the first electrode layer (730) are disposed (or regions corresponding to the pixel definition film (625) of FIG. 7b). Light emitted from the light-emitting layer (750) may travel in the direction of the arrow (or, +z-axis direction) and pass through the protective layer (790) to be visible to the outside. Since the front-emitting display (700) illustrated in FIG. 15b has a relatively simple layer through which light passes compared to the back-emitting display (700) illustrated in FIG. 15a, the luminance of light displayed to the outside may be relatively excellent.

[0158] Fig. 16 is a schematic drawing showing how the light-emitting layer of a display is uniformly formed according to the first embodiment.

[0159] Fig. 17 is a schematic drawing showing a uniform formation of a light-emitting layer of a display according to a second embodiment.

[0160] Fig. 16 <1601> and Fig. 17 <1701> is a drawing showing the appearance of the silver light-emitting layer immediately after printing, and Fig. 16 <1602> and <1702> is a drawing showing the final form after the light-emitting layer is printed and dried. Referring to FIG. 7b and FIG. 9b, FIG. 16 <1601> and <1602> And Fig. 17 <1701> and <1702> In order to help understanding, only a part of the light emitting element (601, 701) (e.g., transistor layer (620, 720), first electrode layer (630, 730), pixel defining film (625)) is illustrated, and the remaining components (e.g., substrate (610, 710), hole transport layer (640, 740)) are omitted. Those skilled in the art will be able to fully understand that the substrate (610, 710) is arranged under the transistor layer (620, 720), and the hole transport layer (640, 740) is arranged over the first electrode layer (630, 730).

[0161] Referring to FIGS. 7b, 9b, 16, and 17, in one embodiment, the light-emitting layer (650, 750) can be uniformly formed on the first electrode layer (630, 730) regardless of the presence or absence of the pixel defining film (625). When an electrophoresis method is used to attach the quantum dots (300) to the substrate (610, 710) according to an electric field after electrical polarity is imparted to the quantum dots (300), the light-emitting layer (650, 750) can be formed as a uniform layer. Accordingly, the phenomenon in which the quantum dots (300) are concentratedly distributed along the tapered surface (628) of the pixel defining film (625) (e.g., pinning phenomenon) can be avoided. In addition, due to the uniformly formed light-emitting layer (650, 750), the display (600, 700) can secure a wide light-emitting area, thereby preventing deterioration of optical characteristics.

[0162] FIG. 18 is a drawing for explaining the width of the light-emitting layer of a display according to one embodiment.

[0163] Referring to FIGS. 1A, 1B, 5A, and 18, in one embodiment, the unidirectional width (e.g., length in the y-axis direction) of the luminescent solution (500) and the luminescent layer (150) formed by drying after the luminescent solution (500) is printed may be set to be less than a certain value. For example, in FIG. 18 <1801> Referring to FIG. 18, the luminescent solution (500) discharged from the nozzle (205) may be formed such that the second direction (e.g., y-axis direction) width (e.g., W4) at the moment of exiting the nozzle (205) is tens of μm (e.g., 25 μm) or less. The luminescent solution (500) may be aligned so that the second direction (e.g., y-axis direction) width (e.g., W5) is several μm (e.g., 0.5 μm to 1 μm) by the electric field formed between the nozzle (205) and the substrate (110). The second direction (e.g., y-axis direction) width (e.g., W6) of the luminescent solution (500) in a state where the luminescent solution (500) is printed on the substrate (110) may be maintained to several μm (e.g., 5 μm) or less. FIG. 18 <1802> With reference to , in one embodiment, the second direction (e.g., y-axis direction) width (e.g., W7) of the light-emitting layer (150) that is finally formed after the light-emitting solution (500) is printed and then dried (or washed) may be formed to be several um (e.g., 5 um) or less.

[0164] FIG. 19 is a schematic diagram illustrating a transistor structure inside a display according to one embodiment.

[0165] Referring to FIGS. 1A, 1B, and 19, in one embodiment, the transistor layer (120) may include a first transistor (121) and a second transistor (122). The first transistor (121) and the second transistor (122) may be electrically connected to each of a plurality of first electrodes provided in the first electrode layer (130). For example, the first transistor (121) may be electrically connected to the first electrode of the first electrode layer (130) to control current flowing to each of the sub-pixels (SP1, SP2, SP3). For example, the second transistor (122) may be electrically connected to the first electrode of the first electrode layer (130) and a ground (not shown). The second transistor (122) may enable static electricity accumulated in the first electrode to be discharged through the ground (not shown) while printing the light-emitting layer (150). The second transistor (122) can protect the first transistor (121) by allowing static electricity to be discharged through the ground (not shown).

[0166] In various embodiments, at least one or a combination of two or more of the shading member (685) of FIG. 14, the shading member (785) of FIGS. 15A and 15B, the sealing layer (780), and the protective layer (790), and the second transistor (122) of FIG. 19 can be applied to the embodiments disclosed in this document.

[0167] According to one embodiment of the present document, a method for manufacturing a display including a plurality of sub-pixels includes the steps of forming a plurality of first electrodes on a substrate; forming a light-emitting layer corresponding to each of the plurality of sub-pixels by continuously printing the light-emitting solution from one side of the substrate to the other side of the substrate while a potential difference is formed between the substrate on which the plurality of first electrodes are formed and a nozzle containing a light-emitting solution; and forming a second electrode on the substrate on which the light-emitting layer is formed, wherein the light-emitting solution may include a quantum dot including a ligand of a polar material and a conductive solvent so as to be able to move along an electric field caused by the potential difference.

[0168] According to one embodiment of the present document, the quantum dot may have a zeta potential.

[0169] According to one embodiment of the present document, when forming the light-emitting layer, a first voltage having the same polarity as the polarity of the quantum dot may be applied to the nozzle, and when forming the light-emitting layer, a second voltage having the opposite polarity to the polarity of the quantum dot may be applied to the substrate.

[0170] According to one embodiment of the present document, the plurality of sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel, and the step of forming the light-emitting layer includes: a step of printing a first color light-emitting layer including a first color quantum dot on the plurality of first electrodes corresponding to the first sub-pixel; a step of printing a second color light-emitting layer including a second color quantum dot on the plurality of first electrodes corresponding to the second sub-pixel; and a step of printing a third color light-emitting layer including a third color quantum dot on the plurality of first electrodes corresponding to the third sub-pixel, wherein at least one of the first color light-emitting layer, the second color light-emitting layer, and the third color light-emitting layer is printed in a first direction from one side of the substrate to the other side of the substrate, and the second color light-emitting layer may be spaced apart from at least one of the first color light-emitting layer and the third color light-emitting layer in a second direction perpendicular to the first direction.

[0171] According to one embodiment of the present document, the step of forming the light-emitting layer may include the step of printing the light-emitting solution on the plurality of first electrodes while a designated first potential difference is formed on the substrate on which the nozzle and the plurality of first electrodes are formed; and the step of printing the light-emitting solution between the plurality of first electrodes while a designated second potential difference lower than the first potential difference is formed on the substrate on which the nozzle and the plurality of first electrodes are formed.

[0172] According to one embodiment of the present document, an alternating current voltage may be applied to the nozzle, and a direct current voltage may be applied to the substrate on which the plurality of first electrodes are formed.

[0173] According to one embodiment of the present document, the step of forming the light-emitting layer may further include the step of cleaning the substrate on which the light-emitting solution is printed to remove the light-emitting solution printed between the plurality of first electrodes.

[0174] According to one embodiment of the present document, the display may further include a step of forming a light-blocking member overlapping an area between the plurality of first electrodes when viewed from above.

[0175] According to one embodiment of the present document, the method further includes forming a sealing layer on the substrate on which the second electrode is formed, and the light-blocking member may be disposed on the sealing layer.

[0176] According to one embodiment of the present document, the method further includes forming a first transistor and a second transistor that are commonly connected to each of the plurality of first electrodes, wherein the second transistor can be connected to ground when forming the light-emitting layer.

[0177] According to one embodiment of the present document, the thickness of the light-emitting layer may be formed to be 5 nm to 100 nm, and the width of at least one of the light-emitting layer of the first color, the light-emitting layer of the second color, and the light-emitting layer of the third color in the second direction may be formed to be 5 um or less.

[0178] According to one embodiment of this document, the potential difference is 1x10 9 V / m to 2x10 5 It can have a range of V / m.

[0179] According to one embodiment of the present document, the method further includes forming a pixel defining film on a substrate on which the plurality of first electrodes are formed, and on the pixel defining film spaced apart in a first direction from one side of the substrate to the other side of the substrate, quantum dots identical to those included in the light-emitting layer arranged on the first electrodes spaced apart in the first direction may be arranged.

[0180] According to one embodiment of the present invention, the quantum dot comprises a core, a shell, and the ligand, wherein the ligand can be substituted with a polar organic material.

[0181] According to one embodiment of the present document, the quantum dot is MgO, MgS, MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrS, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al2O3, Al2S3, Al2Se3, Al2Te3, Ga2O3, Ga2S3, Ga2Se3, Ga2Te3, In2O3, In2S3, In2Se3, In2Te3, SiO2, GeO2, SnO2, SnS, SnSe, SnTe, PbO, PbO2, PbS, PbSe, PbTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, At least one of GaSb, InN, InP, InAs, InSb, BP, Si and Ge is included, and the conductive solvent is alcohol, dipropylene glycol monomethyl, ether acetate (DPMA), ethyl acetate, n-butyl acetate, isobutyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol n-butyl ether acetate, diethylene glycol dimethyl ether, dipropylene glycol monomethyl, ether acetate, diethylene glycol methyl ethyl ether, diethylene glycol ethyl ether acetate, dipropylene glycol n-butyl ether, tripropylene glycol n-propyl ether, tripropylene glycol methyl ether, propylene glycol methyl ether acetate, propylene glycol diacetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether acetate, cyclohexanone, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, It may include at least one of 3-ethoxypropionate ethyl, ethylene glycol n-butyl ether acetate (EGBEA), dipropylene glycol monomethyl ether acetate (DPMA), propylene glycol diacetate (PGDA), diethylene glycol monoethyl ether (DPGME), and diethylene glycol monoethyl ether (Carbitol).

[0182] According to one embodiment of the present document, a display including a plurality of sub-pixels that implement different colors includes a substrate; a plurality of first electrodes disposed on the substrate; a second electrode disposed on the plurality of first electrodes; and an emission layer disposed between each of the plurality of first electrodes and the second electrode, the emission layer corresponding to each of the plurality of sub-pixels, wherein the emission layer is formed of a quantum dot including a ligand having an electrical polarity that generates an attractive force in a direction toward the substrate, and the quantum dot can have a zeta potential.

[0183] According to one embodiment of the present document, the device further comprises a hole transport layer disposed between the first electrode and the light-emitting layer; and an electron transport layer disposed between the second electrode and the light-emitting layer, wherein the hole transport layer and the electron transport layer can be in direct contact in a region between the plurality of first electrodes.

[0184] According to one embodiment of the present document, a pixel defining film disposed between the plurality of sub-pixels; and at least a portion of an upper surface of the pixel defining film facing the second electrode further includes a protrusion disposed along an edge, wherein the protrusion may include the same quantum dots as the light-emitting layer spaced apart from the protrusion.

[0185] According to one embodiment of the present document, when the display is viewed from above, a light-blocking member may be further included that overlaps an area between the plurality of first electrodes.

[0186] According to one embodiment of the present document, the present invention further includes a sealing layer disposed on the second electrode, and the light-shielding member may be disposed on the sealing layer.

[0187] FIG. 20 is a block diagram of an electronic device within a network environment according to various embodiments.

[0188] Referring to FIG. 20, in a network environment (2000), an electronic device (2001) may communicate with an electronic device (2002) via a first network (2098) (e.g., a short-range wireless communication network), or may communicate with at least one of an electronic device (2004) or a server (2008) via a second network (2099) (e.g., a long-range wireless communication network). In one embodiment, the electronic device (2001) may communicate with the electronic device (2004) via the server (2008). According to one embodiment, the electronic device (2001) may include a processor (2020), a memory (2030), an input module (2050), an audio output module (2055), a display module (2060), an audio module (2070), a sensor module (2076), an interface (2077), a connection terminal (2078), a haptic module (2079), a camera module (2080), a power management module (2088), a battery (2089), a communication module (2090), a subscriber identification module (2096), or an antenna module (2097). In some embodiments, the electronic device (2001) may omit at least one of these components (e.g., the connection terminal (2078)), or may have one or more other components added. In some embodiments, some of these components (e.g., sensor module (2076), camera module (2080), or antenna module (2097)) may be integrated into a single component (e.g., display module (2060)).

[0189] The processor (2020) may, for example, execute software (e.g., a program (2040)) to control at least one other component (e.g., a hardware or software component) of the electronic device (2001) connected to the processor (2020) and perform various data processing or operations. According to one embodiment, as at least a part of the data processing or operations, the processor (2020) may store commands or data received from other components (e.g., a sensor module (2076) or a communication module (2090)) in the volatile memory (2032), process the commands or data stored in the volatile memory (2032), and store the resulting data in the non-volatile memory (2034). According to one embodiment, the processor (2020) may include a main processor (2021) (e.g., a central processing unit or an application processor) or a secondary processor (2023) (e.g., a graphics processing unit, a neural processing unit (NPU), an image signal processor, a sensor hub processor, or a communication processor) that can operate independently or together with the main processor (2021). For example, when the electronic device (2001) includes the main processor (2021) and the secondary processor (2023), the secondary processor (2023) may be configured to use less power than the main processor (2021) or to be specialized for a given function. The secondary processor (2023) may be implemented separately from the main processor (2021) or as a part thereof.

[0190] The auxiliary processor (2023) may control at least a portion of functions or states associated with at least one component (e.g., the display module (2060), the sensor module (2076), or the communication module (2090)) of the electronic device (2001), for example, on behalf of the main processor (2021) while the main processor (2021) is in an inactive (e.g., sleep) state, or together with the main processor (2021) while the main processor (2021) is in an active (e.g., application execution) state. In one embodiment, the auxiliary processor (2023) (e.g., an image signal processor or a communication processor) may be implemented as a part of another functionally related component (e.g., a camera module (2080) or a communication module (2090)). In one embodiment, the auxiliary processor (2023) (e.g., a neural network processing unit) may include a hardware structure specialized for processing artificial intelligence models. The artificial intelligence models may be generated through machine learning. This learning can be performed, for example, on the electronic device (2001) itself where the artificial intelligence model is executed, or can be performed through a separate server (e.g., server (2008)). The learning algorithm can include, for example, supervised learning, unsupervised learning, semi-supervised learning, or reinforcement learning, but is not limited to the examples described above. The artificial intelligence model can include multiple artificial neural network layers.The artificial neural network may be one of a deep neural network (DNN), a convolutional neural network (CNN), a recurrent neural network (RNN), a restricted Boltzmann machine (RBM), a deep belief network (DBN), a bidirectional recurrent deep neural network (BRDNN), a deep Q-network, or a combination of two or more of the above, but is not limited to the examples described above. In addition to, or alternatively to, a hardware structure, an artificial intelligence model may include a software structure.

[0191] The memory (2030) can store various data used by at least one component (e.g., the processor (2020) or the sensor module (2076)) of the electronic device (2001). The data can include, for example, software (e.g., the program (2040)) and input data or output data for commands related thereto. The memory (2030) can include volatile memory (2032) or non-volatile memory (2034).

[0192] The program (2040) may be stored as software in memory (2030) and may include, for example, an operating system (2042), middleware (2044), or an application (2046).

[0193] The input module (2050) can receive commands or data to be used in a component of the electronic device (2001) (e.g., a processor (2020)) from an external source (e.g., a user) of the electronic device (2001). The input module (2050) can include, for example, a microphone, a mouse, a keyboard, a key (e.g., a button), or a digital pen (e.g., a stylus pen).

[0194] The audio output module (2055) can output audio signals to the outside of the electronic device (2001). The audio output module (2055) can include, for example, a speaker or a receiver. The speaker can be used for general purposes, such as multimedia playback or recording playback. The receiver can be used to receive incoming calls. In one embodiment, the receiver can be implemented separately from the speaker or as part of the speaker.

[0195] The display module (2060) can visually provide information to an external party (e.g., a user) of the electronic device (2001). The display module (2060) may include, for example, a display, a holographic device, or a projector and a control circuit for controlling the device. In one embodiment, the display module (2060) may include a touch sensor configured to detect a touch, or a pressure sensor configured to measure the intensity of a force generated by the touch.

[0196] The audio module (2070) can convert sound into an electrical signal, or vice versa. According to one embodiment, the audio module (2070) can acquire sound through the input module (2050), output sound through the sound output module (2055), or an external electronic device (e.g., electronic device (2002)) (e.g., speaker or headphone) directly or wirelessly connected to the electronic device (2001).

[0197] The sensor module (2076) can detect the operating status (e.g., power or temperature) of the electronic device (2001) or the external environmental status (e.g., user status) and generate an electrical signal or data value corresponding to the detected status. According to one embodiment, the sensor module (2076) can include, for example, a gesture sensor, a gyro sensor, a barometric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an IR (infrared) sensor, a biometric sensor, a temperature sensor, a humidity sensor, or an illuminance sensor.

[0198] The interface (2077) may support one or more designated protocols that may be used to directly or wirelessly connect the electronic device (2001) to an external electronic device (e.g., the electronic device (2002)). In one embodiment, the interface (2077) may include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, an SD card interface, or an audio interface.

[0199] The connection terminal (2078) may include a connector through which the electronic device (2001) may be physically connected to an external electronic device (e.g., the electronic device (2002)). In one embodiment, the connection terminal (2078) may include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (e.g., a headphone connector).

[0200] The haptic module (2079) can convert electrical signals into mechanical stimuli (e.g., vibration or movement) or electrical stimuli that a user can perceive through tactile or kinesthetic sensations. In one embodiment, the haptic module (2079) may include, for example, a motor, a piezoelectric element, or an electrical stimulation device.

[0201] The camera module (2080) can capture still images and videos. In one embodiment, the camera module (2080) may include one or more lenses, image sensors, image signal processors, or flashes.

[0202] The power management module (2088) can manage power supplied to the electronic device (2001). According to one embodiment, the power management module (2088) can be implemented as, for example, at least a part of a power management integrated circuit (PMIC).

[0203] A battery (2089) may power at least one component of the electronic device (2001). In one embodiment, the battery (2089) may include, for example, a non-rechargeable primary battery, a rechargeable secondary battery, or a fuel cell.

[0204] The communication module (2090) may support the establishment of a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device (2001) and an external electronic device (e.g., electronic device (2002), electronic device (2004), or server (2008)), and the performance of communication through the established communication channel. The communication module (2090) may operate independently from the processor (2020) (e.g., application processor) and may include one or more communication processors that support direct (e.g., wired) communication or wireless communication. According to one embodiment, the communication module (2090) may include a wireless communication module (2092) (e.g., a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module (2094) (e.g., a local area network (LAN) communication module, or a power line communication module). Any of these communication modules may communicate with an external electronic device (2004) via a first network (2098) (e.g., a short-range communication network such as Bluetooth, wireless fidelity (WiFi) direct, or infrared data association (IrDA)) or a second network (2099) (e.g., a long-range communication network such as a legacy cellular network, a 5G network, a next-generation communication network, the Internet, or a computer network (e.g., a LAN or WAN)). These various types of communication modules may be integrated into a single component (e.g., a single chip) or implemented as multiple separate components (e.g., multiple chips). The wireless communication module (2092) may use subscriber information (e.g., an international mobile subscriber identity (IMSI)) stored in the subscriber identification module (2096) to verify or authenticate the electronic device (2001) within a communication network such as the first network (2098) or the second network (2099).

[0205] The wireless communication module (2092) can support 5G networks and next-generation communication technologies following the 4G network, such as NR access technology (new radio access technology). NR access technology can support high-speed transmission of high-capacity data (eMBB (enhanced mobile broadband)), minimizing terminal power and connecting multiple terminals (mMTC (massive machine type communications)), or high reliability and low latency (URLLC (ultra-reliable and low-latency communications)). The wireless communication module (2092) can support, for example, a high-frequency band (e.g., mmWave band) to achieve a high data transmission rate. The wireless communication module (2092) can support various technologies for securing performance in high-frequency bands, such as beamforming, massive multiple-input and multiple-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, or large scale antenna. The wireless communication module (2092) can support various requirements specified in the electronic device (2001), an external electronic device (e.g., the electronic device (2004)), or a network system (e.g., the second network (2099)). According to one embodiment, the wireless communication module (2092) may support a peak data rate (e.g., 20 Gbps or more) for eMBB realization, a loss coverage (e.g., 164 dB or less) for mMTC realization, or a U-plane latency (e.g., 0.5 ms or less for downlink (DL) and uplink (UL), or 1 ms or less for round trip) for URLLC realization.

[0206] The antenna module (2097) can transmit or receive signals or power to or from an external device (e.g., an external electronic device). In one embodiment, the antenna module (2097) may include an antenna including a radiator formed of a conductor or a conductive pattern formed on a substrate (e.g., a PCB). In one embodiment, the antenna module (2097) may include a plurality of antennas (e.g., an array antenna). In this case, at least one antenna suitable for a communication method used in a communication network, such as the first network (2098) or the second network (2099), may be selected from the plurality of antennas, for example, by the communication module (2090). A signal or power may be transmitted or received between the communication module (2090) and an external electronic device via the selected at least one antenna. In some embodiments, in addition to the radiator, another component (e.g., a radio frequency integrated circuit (RFIC)) may be additionally formed as a part of the antenna module (2097).

[0207] According to various embodiments, the antenna module (2097) may form a mmWave antenna module. In one embodiment, the mmWave antenna module may include a printed circuit board, an RFIC disposed on or adjacent a first side (e.g., a bottom side) of the printed circuit board and capable of supporting a designated high frequency band (e.g., a mmWave band), and a plurality of antennas (e.g., an array antenna) disposed on or adjacent a second side (e.g., a top side or a side side) of the printed circuit board and capable of transmitting or receiving signals in the designated high frequency band.

[0208] At least some of the above components can be interconnected and exchange signals (e.g., commands or data) with each other via a communication method between peripheral devices (e.g., a bus, GPIO (general purpose input and output), SPI (serial peripheral interface), or MIPI (mobile industry processor interface)).

[0209] According to one embodiment, commands or data may be transmitted or received between the electronic device (2001) and an external electronic device (2004) via a server (2008) connected to a second network (2099). Each of the external electronic devices (2002 or 2004) may be the same or a different type of device as the electronic device (2001). According to one embodiment, all or part of the operations executed in the electronic device (2001) may be executed in one or more of the external electronic devices (2002, 2004, or 2008). For example, when the electronic device (2001) is to perform a certain function or service automatically or in response to a request from a user or another device, the electronic device (2001) may, instead of or in addition to executing the function or service itself, request one or more external electronic devices to perform the function or at least a part of the service. One or more external electronic devices that receive the request may execute at least a portion of the requested function or service, or an additional function or service related to the request, and transmit the result of the execution to the electronic device (2001). The electronic device (2001) may process the result as is or additionally and provide it as at least a portion of a response to the request. For this purpose, cloud computing, distributed computing, mobile edge computing (MEC), or client-server computing technology may be used, for example. The electronic device (2001) may provide an ultra-low latency service by using distributed computing or mobile edge computing, for example. In another embodiment, the external electronic device (2004) may include an Internet of Things (IoT) device. The server (2008) may be an intelligent server utilizing machine learning and / or a neural network.According to one embodiment, an external electronic device (2004) or server (2008) may be included within the second network (2099). The electronic device (2001) may be applied to intelligent services (e.g., smart homes, smart cities, smart cars, or healthcare) based on 5G communication technology and IoT-related technology.

[0210] FIG. 21 is a block diagram of a display module according to various embodiments.

[0211] Referring to FIG. 21, a display module (2160) may include a display (2110) and a display driver IC (DDI) (2130) for controlling the display (2110). The DDI (2130) may include an interface module (2131), a memory (2133) (e.g., a buffer memory), an image processing module (2135), or a mapping module (2137). The DDI (2130) may receive image information including, for example, image data or an image control signal corresponding to a command for controlling the image data, from another component of the electronic device 2101 through the interface module (2131). For example, according to one embodiment, image information may be received from a processor (2120) (e.g., a main processor (2121) (e.g., an application processor) or an auxiliary processor (2123) (e.g., a graphics processing unit) that operates independently of the function of the main processor (2121). The DDI (2130) may communicate with a touch circuit (2150) or a sensor module (2176) through the interface module (2131). In addition, the DDI (2130) may store at least a part of the received image information in the memory (2133), for example, in units of frames. The image processing module (2135) may, for example, perform preprocessing or postprocessing (e.g., resolution, brightness, or size adjustment) on at least a part of the image data based on at least a characteristic of the image data or a characteristic of the display (2110). The mapping module (2137) may output a voltage value or a value corresponding to the image data preprocessed or postprocessed through the image processing module (2135). A current value can be generated. In one embodiment, the generation of the voltage value or current value can be performed at least in part based on, for example, the properties of the pixels of the display (2110), such as the arrangement of the pixels (RGB stripe or pentile structure), or the size of each sub-pixel.At least some pixels of the display (2110) may be driven based at least in part on, for example, the voltage value or current value, so that visual information (e.g., text, an image, or an icon) corresponding to the image data may be displayed through the display (2110).

[0212] According to one embodiment, the display module (2160) may further include a touch circuit (2150). The touch circuit (2150) may include a touch sensor (2151) and a touch sensor IC (2153) for controlling the same. The touch sensor IC (2153) may control the touch sensor (2151) to detect, for example, a touch input or a hovering input for a specific location of the display (2110). For example, the touch sensor IC (2153) may detect the touch input or the hovering input by measuring a change in a signal (e.g., voltage, light amount, resistance, or charge amount) for a specific location of the display (2110). The touch sensor IC (2153) may provide information (e.g., location, area, pressure, or time) regarding the detected touch input or hovering input to the processor (2120). According to one embodiment, at least a portion of the touch circuit (2150) (e.g., touch sensor IC (2153)) may be included as part of the display driver IC (2130), or as part of the display (2110), or as part of another component (e.g., auxiliary processor (2123)) disposed external to the display module (2160).

[0213] According to one embodiment, the display module (2160) may further include at least one sensor (e.g., a fingerprint sensor, an iris sensor, a pressure sensor, or an illuminance sensor) of the sensor module (2176), or a control circuit therefor. In this case, the at least one sensor or the control circuit therefor may be embedded in a part of the display module (2160) (e.g., the display (2110) or the DDI (2130)) or a part of the touch circuit (2150). For example, when the sensor module (2176) embedded in the display module (2160) includes a biometric sensor (e.g., a fingerprint sensor), the biometric sensor may obtain biometric information (e.g., a fingerprint image) associated with a touch input through a part of the display (2110). For another example, if the sensor module (2176) embedded in the display module (2160) includes a pressure sensor, the pressure sensor may obtain pressure information associated with a touch input through a portion or the entire area of ​​the display (2110). According to one embodiment, the touch sensor (2151) or the sensor module (2176) may be disposed between pixels of a pixel layer of the display (2110), or above or below the pixel layer.

[0214] Electronic devices according to the various embodiments disclosed in this document may take various forms. Electronic devices may include, for example, portable communication devices (e.g., smartphones), computer devices, portable multimedia devices, portable medical devices, cameras, wearable devices, or home appliances. Electronic devices according to the embodiments of this document are not limited to the aforementioned devices.

[0215] The various embodiments of this document and the terminology used therein are not intended to limit the technical features described in this document to specific embodiments, but should be understood to include various modifications, equivalents, or substitutes of the embodiments. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more of the items, unless the context clearly indicates otherwise. In this document, each of the phrases "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", and "at least one of A, B, or C" can include any one of the items listed together in the corresponding phrase among those phrases, or all possible combinations thereof. Terms such as "first," "second," or "first" or "second" may be used merely to distinguish one component from another, and do not limit the components in any other respect (e.g., importance or order). When a component (e.g., a first component) is referred to as "coupled" or "connected" to another component (e.g., a second component), with or without the terms "functionally" or "communicatively," it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0216] The term "module" used in various embodiments of this document may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit. A module may be an integral component, or a minimum unit or part of such a component that performs one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application-specific integrated circuit (ASIC).

[0217] Various embodiments of the present document may be implemented as software (e.g., a program (2040)) including one or more instructions stored in a storage medium (e.g., an internal memory (2036) or an external memory (2038)) readable by a machine (e.g., an electronic device (2001)). For example, a processor (e.g., a processor (2020)) of the machine (e.g., an electronic device (2001)) may call at least one instruction among the one or more instructions stored from the storage medium and execute it. This enables the machine to operate to perform at least one function according to the at least one called instruction. The one or more instructions may include code generated by a compiler or code executable by an interpreter. The machine-readable storage medium may be provided in the form of a non-transitory storage medium. Here, 'non-transitory' simply means that the storage medium is a tangible device and does not contain signals (e.g., electromagnetic waves), and the term does not distinguish between cases where data is stored semi-permanently or temporarily on the storage medium.

[0218] According to one embodiment, the method according to various embodiments disclosed in this document may be provided as included in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or may be distributed online (e.g., downloaded or uploaded) via an application store (e.g., Play Store™) or directly between two user devices (e.g., smart phones). In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily generated in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

[0219] According to various embodiments, each component (e.g., a module or a program) of the above-described components may include one or more entities, and some of the entities may be separated and placed in other components. According to various embodiments, one or more components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (e.g., a module or a program) may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the plurality of components identically or similarly to those performed by the corresponding component among the plurality of components prior to the integration. According to various embodiments, the operations performed by a module, program, or other component may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

Claims

1. A method for manufacturing a display including a plurality of sub-pixels, A step of forming a plurality of first electrodes on a substrate; A step of forming a light-emitting layer corresponding to each of the plurality of sub-pixels by continuously printing the light-emitting solution from one side of the substrate to the other side of the substrate while a potential difference is formed between the substrate on which the plurality of first electrodes are formed and the nozzle containing the light-emitting solution; A step of forming a second electrode on a substrate on which the above light-emitting layer is formed, The above luminescent solution is, A method for manufacturing a display comprising a quantum dot including a ligand of a polar substance and a conductive solvent so as to be able to move along an electric field due to the above potential difference.

2. In claim 1, A method for manufacturing a display wherein the above quantum dots have a zeta potential.

3. In claim 1, When forming the above light-emitting layer, a first voltage having the same polarity as the polarity of the quantum dot is applied to the nozzle, A method for manufacturing a display, wherein, when forming the light-emitting layer, a second voltage having a polarity opposite to that of the quantum dot is applied to the substrate.

4. In claim 3, The above plurality of sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel, The step of forming the above-mentioned light-emitting layer is: A step of printing a first color emitting layer including a first color quantum dot on the plurality of first electrodes corresponding to the first sub-pixel; A step of printing a second color light-emitting layer including a second color quantum dot on the plurality of first electrodes corresponding to the second sub-pixel; A step of printing a third color light-emitting layer including a third color quantum dot on the plurality of first electrodes corresponding to the third sub-pixel, At least one of the light-emitting layer of the first color, the light-emitting layer of the second color, and the light-emitting layer of the third color is printed in a first direction from one side of the substrate to the other side of the substrate, A method for manufacturing a display, wherein the light-emitting layer of the second color is spaced apart from at least one of the light-emitting layer of the first color and the light-emitting layer of the third color in a second direction perpendicular to the first direction.

5. In claim 1, The step of forming the above-mentioned light-emitting layer is A step of printing the luminescent solution on the plurality of first electrodes while a specified first potential difference is formed on the substrate on which the nozzle and the plurality of first electrodes are formed; A method for manufacturing a display, comprising the step of printing the luminescent solution between the plurality of first electrodes while a designated second potential difference lower than the first potential difference is formed on the substrate on which the nozzle and the plurality of first electrodes are formed.

6. In claim 5, An alternating voltage is applied to the above nozzle, A method for manufacturing a display in which a direct current voltage is applied to a substrate on which the plurality of first electrodes are formed.

7. In claim 6, The step of forming the above-mentioned light-emitting layer is A method for manufacturing a display, further comprising the step of cleaning a substrate on which the luminescent solution is printed to remove the luminescent solution printed between the plurality of first electrodes.

8. In claim 1, A method for manufacturing a display, further comprising the step of forming a light-blocking member overlapping an area between the plurality of first electrodes when viewing the display from above.

9. In claim 8, It further includes a step of forming a sealing layer on the substrate on which the second electrode is formed, A method for manufacturing a display, wherein the above-mentioned light-blocking member is placed on the above-mentioned sealing layer.

10. In claim 1, Further comprising a step of forming a first transistor and a second transistor commonly connected to each of the plurality of first electrodes, A method for manufacturing a display in which the second transistor is connected to ground when forming the light-emitting layer.

11. In claim 1, It further includes a step of forming a pixel defining film on a substrate on which the plurality of first electrodes are formed, A method for manufacturing a display, wherein quantum dots identical to those included in a light-emitting layer arranged on first electrodes spaced apart in the first direction are arranged on the pixel defining film spaced apart in a first direction from one side of the substrate to the other side of the substrate.

12. In claim 1, The quantum dot comprises a core, a shell, and the ligand, A method for manufacturing a display in which the above ligand is substituted with a polar organic substance.

13. In a display comprising multiple sub-pixels that implement different colors, substrate and; A plurality of first electrodes arranged on the substrate; A second electrode disposed on the plurality of first electrodes; A light-emitting layer is disposed between each of the plurality of first electrodes and the second electrode, and includes a light-emitting layer corresponding to each of the plurality of sub-pixels, The above light-emitting layer is formed of a quantum dot including a ligand having an electrical polarity that generates an attractive force in a direction toward the substrate, A display in which the above quantum dots have a zeta potential.

14. In claim 13, A hole transport layer disposed between the first electrode and the light-emitting layer; It further comprises an electron transport layer disposed between the second electrode and the light-emitting layer, A display in which the hole transport layer and the electron transport layer are in direct contact with each other in the region between the plurality of first electrodes.

15. In claim 13, A pixel defining film disposed between the plurality of sub-pixels; At least a portion of the upper surface of the pixel definition film facing the second electrode further includes a protrusion arranged along an edge, A display wherein the protrusion comprises quantum dots identical to the light-emitting layer spaced apart from the protrusion.

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