Display device manufacturing apparatus and display device manufacturing method

Abstract

The display device manufacturing apparatus includes a stage on which a display device substrate is placed, a mold including a surface including recessed portions, an application device that applies ink including light-emitting elements to the surface of the mold, a doctor blade that removes the ink placed on the surface of the mold while leaving the ink placed in the recessed portions of the mold, and a bonding device that bonds the surface of the mold to the substrate.

Description

[Technical Field]

[0001] The present invention relates to a display device manufacturing apparatus and a display device manufacturing method. [Background technology]

[0002] 2. Description of the Related Art In recent years, with the growing interest in information displays, research and development into display devices has been continuously carried out. Summary of the Invention [Problem to be solved by the invention]

[0003] One object of the present invention is to provide a display device manufacturing apparatus that includes a mold having recesses (concave portions) corresponding to the arrangement of light-emitting elements, and a doctor blade that removes ink from the surface of the mold, and that uses the mold to arrange light-emitting elements on a substrate of the display device.

[0004] Another object of the present invention is to provide a method for manufacturing a display device using the manufacturing apparatus.

[0005] However, the object of the present invention is not limited to the above-mentioned object, and can be expanded in various ways without departing from the spirit and scope of the present invention. [Means for solving the problem]

[0006] In order to achieve one object of the present invention, an apparatus for manufacturing a display device according to an embodiment of the present invention may include a stage on which a display device substrate is placed, a mold having a surface including recessed portions, an application device that applies ink including light-emitting elements to the surface of the mold, a doctor blade that removes the ink placed on the surface of the mold while leaving the ink placed in the recessed portions of the mold, and a bonding device that bonds (butts) the surface of the mold to the substrate.

[0007] According to one embodiment, the depth of each of the recesses may be greater than the diameter of each of the light-emitting elements, and the depth of each of the recesses may be less than about 1.5 times the diameter of each of the light-emitting elements.

[0008] According to an embodiment, each of the recessed portions may include an alignment hole filled with at least one of the light emitting elements.

[0009] According to one embodiment, the length of the alignment hole in a first direction may be longer than the length of each of the light-emitting elements, the width of the alignment hole in a second direction intersecting the first direction may be larger than the diameter, and the width of the alignment hole in the second direction may be smaller than approximately 1.5 times the diameter.

[0010] According to an embodiment, the recessed portions may be arranged in the first direction and the second direction, and the recessed portions may be arranged corresponding to the arrangement of the light emitting devices on the substrate.

[0011] According to one embodiment, the doctor blade scrapes the ink in one direction on the surface of the mold, so that the light emitting elements can be arranged in accordance with the alignment pattern of the recessed portions.

[0012] According to an embodiment, the bottom surface of the alignment hole may be flat.

[0013] According to an embodiment, the alignment hole may include a curved or inclined surface.

[0014] According to an embodiment, each of the recessed portions may further include a step or an inclined surface adjacent to the alignment hole.

[0015] According to an embodiment, the manufacturing apparatus may further include a drying device that evaporates and removes a solvent of the ink remaining on the surface of the mold or the surface of the substrate.

[0016] According to an embodiment, the manufacturing apparatus may further include a vibration device that vibrates the substrate or the mold on which the ink is applied.

[0017] According to an embodiment, the vibration device may generate sound waves or ultrasonic waves to vibrate the mold, and at least one of the light emitting elements may be filled into each of the recesses by the vibration device.

[0018] According to one embodiment, the vibration device can vibrate the substrate when the mold and the substrate are separated.

[0019] According to an embodiment, the manufacturing apparatus may further include an electric field applying device that applies an electric field to the substrate to fix the positions of the light emitting devices when the mold and the substrate are separated.

[0020] In order to achieve one object of the present invention, a method for manufacturing a display device according to an embodiment of the present invention may include the steps of applying ink including a light-emitting element to a surface of a mold including a recessed portion, using a doctor blade to remove the ink disposed on the surface of the mold while leaving the ink disposed in the recessed portion of the mold, bonding the mold to a substrate of a display device and disposing the light-emitting element on an electrode formed on the substrate, and separating the mold from which the light-emitting element has been separated from the substrate.

[0021] According to one embodiment, the step of removing the ink may include the steps of aligning the light-emitting elements by scraping the surface of the mold with the doctor blade, and removing the ink solvent remaining on the surface of the mold by irradiating the surface of the mold with light.

[0022] According to one embodiment, the step of removing the ink may include the steps of vibrating the mold using a vibration device so that at least a portion of the light-emitting element is filled in the recess portion, aligning the light-emitting element by scraping the surface of the mold with the doctor blade, and removing the ink solvent remaining on the surface of the mold by irradiating light onto the surface of the mold.

[0023] According to one embodiment, the step of separating the mold from the substrate may include a step of fixing the light-emitting element on the electrode by applying an electric field to the substrate using an electric field application device, and a step of moving the mold vertically to separate it from the substrate.

[0024] According to one embodiment, the step of separating the mold from the substrate may further include a step of removing the ink solvent remaining on the surface of the substrate by irradiating light onto the substrate from which the mold has been separated.

[0025] According to one embodiment, the step of separating the mold from the substrate may include the steps of fixing the light-emitting element on the electrode by applying an electric field to the substrate using an electric field application device, applying vibration to the substrate using a vibration device, and moving the mold vertically to separate it from the substrate. [Effects of the Invention]

[0026] The display device manufacturing apparatus and method according to the present invention can provide pre-positioned light emitting devices on electrodes of a substrate using an arrangement of recesses in a mold, thereby significantly reducing misalignment of the light emitting devices, thereby reducing product defects and improving alignment reliability and manufacturing yield.

[0027] However, the effects of the present invention are not limited to the above-mentioned effects, and may be expanded in various ways without departing from the spirit and scope of the present invention. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a perspective view schematically illustrating a light emitting device according to an embodiment of the present invention. [Figure 2] 2 is a schematic cross-sectional view showing an example of the light-emitting element of FIG. 1. FIG. [Figure 3] 1 is a schematic plan view showing a display device according to an embodiment of the present invention; [Figure 4] FIG. 4 is a schematic diagram illustrating an example of a pixel included in the display device of FIG. [Figure 5] 1 is a schematic diagram showing a manufacturing apparatus for a display device according to an embodiment of the present invention; [Figure 6a] 6 is a schematic cross-sectional view showing an example of a part of a mold included in the manufacturing apparatus of FIG. 5. [Figure 6b] FIG. 6b is a schematic plan view showing an example of a portion of the mold of FIG. 6a. [Figure 7] 6 is a schematic cross-sectional view showing another example of a part of a mold included in the manufacturing apparatus of FIG. 5. [Figure 8] 6 is a schematic cross-sectional view showing another example of a part of a mold included in the manufacturing apparatus of FIG. 5. [Figure 9] 6 is a schematic cross-sectional view showing another example of a part of a mold included in the manufacturing apparatus of FIG. 5. [Figure 10] 6 is a schematic cross-sectional view showing another example of a part of a mold included in the manufacturing apparatus of FIG. 5. [Figure 11] 6 is a schematic cross-sectional view showing another example of a part of a mold included in the manufacturing apparatus of FIG. 5. [Figure 12] 6 is a schematic cross-sectional view showing another example of a part of a mold included in the manufacturing apparatus of FIG. 5. [Figure 13] 6 is a schematic diagram showing another example of the manufacturing apparatus for the display device of FIG. 5. FIG. [Figure 14]6 is a schematic diagram showing still another example of the manufacturing apparatus for the display device of FIG. 5. FIG. [Figure 15] 6 is a schematic diagram showing still another example of the manufacturing apparatus for the display device of FIG. 5. FIG. [Figure 16] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 17] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 18] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 19] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 20] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 21] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 22] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 23] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 24] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 25] 1A to 1C are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention. [Figure 26] 26A to 26C are schematic views showing an example of a step of separating the substrate and mold in FIG. 25. [Figure 27] FIG. 26 is a schematic view showing another example of the step of separating the substrate and the mold in FIG. 25. [Figure 28] 10A to 10C are diagrams illustrating an example of a process for removing the solvent from the ink. DETAILED DESCRIPTION OF THE INVENTION

[0029] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. The same reference numerals are used to designate the same components in the drawings, and redundant descriptions of the same components will be omitted.

[0030] The examples described in this specification are intended to clearly explain the concept of the present invention to those skilled in the art to which the present invention pertains, and the present invention is not limited to the examples described in this specification. The scope of the present invention should be interpreted as including modifications or variations that do not deviate from the concept of the present invention.

[0031] The drawings attached to this specification are intended to facilitate the explanation of the present invention, and the shapes shown in the drawings may be exaggerated as necessary to facilitate understanding of the present invention, and therefore the present invention is not limited by the drawings.

[0032] In this specification, if it is determined that a detailed description of a known structure or function related to the present invention would obscure the gist of the present invention, the detailed description thereof will be omitted as necessary.

[0033] FIG. 1 is a schematic perspective view showing a light emitting device according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view showing an example of the light emitting device of FIG.

[0034] In the embodiments, the type and / or shape of the light emitting element LD are not limited to those in the embodiments shown in FIGS.

[0035] 1 and 2, the light-emitting device LD may include a first semiconductor layer 11, a second semiconductor layer 13, and an active layer 12 interposed between the first and second semiconductor layers 11 and 13. As an example, the light-emitting device LD may be realized as a light-emitting stack (or stack pattern) in which the first semiconductor layer 11, the active layer 12, and the second semiconductor layer 13 are sequentially stacked.

[0036] The light emitting element LD may be formed in a shape extending in one direction. If the extension direction of the light emitting element LD is defined as the length direction, the light emitting element LD may include a first end portion EP1 and a second end portion EP2 along the length direction. One of the first semiconductor layer 11 and the second semiconductor layer 13 may be located at the first end portion EP1 of the light emitting element LD, and the other of the first semiconductor layer 11 and the second semiconductor layer 13 may be located at the second end portion EP2 of the light emitting element LD. For example, the second semiconductor layer 13 may be located at the first end portion EP1 of the light emitting element LD, and the first semiconductor layer 11 may be located at the second end portion EP2 of the light emitting element LD.

[0037] The light emitting element LD may be formed in various shapes. As an example, the light emitting element LD may have a rod-like shape, a bar-like shape, or a columnar shape that is long in the length direction (or has an aspect ratio greater than 1), as shown in FIG. 1 . As another example, the light emitting element LD may have a rod-like shape, a bar-like shape, or a columnar shape that is short in the length direction (or has an aspect ratio less than 1). As yet another example, the light emitting element LD may have a rod-like shape, a bar-like shape, or a columnar shape with an aspect ratio of 1. Alternatively, the diameter D of the first end EP1 and the diameter D of the second end EP2 may be different.

[0038] The light emitting element LD may have a diameter D and / or length L of about nanoscale (or nanometer) to microscale (or micrometer), for example. For example, the light emitting element LD may be a light emitting diode (LED) type.

[0039] For example, the first semiconductor layer 11 may include at least one n-type semiconductor layer. For example, the first semiconductor layer 11 may be an n-type semiconductor layer including one of semiconductor materials such as InAlGaN, GaN, AlGaN, InGaN, AlN, and InN, and doped with a dopant of first conductivity (or an n-type dopant) such as Si, Ge, or Sn. However, the material constituting the first semiconductor layer 11 is not limited thereto, and the first semiconductor layer 11 may be formed using various other materials.

[0040] The active layer 12 is disposed on the first semiconductor layer 11 and may have a single quantum well or multiple quantum well structure. For example, when the active layer 12 has a multiple quantum well structure, the active layer 12 may have a barrier layer, a strain reinforcing layer, and a well layer periodically stacked as a single unit. The strain reinforcing layer has a smaller lattice constant than the barrier layer and can further strengthen the strain, e.g., compressive strain, applied to the well layer. However, the structure of the active layer 12 is not limited to the above embodiment.

[0041] The active layer 12 may emit light having a wavelength of about 400 nm to about 900 nm and may have a double heterostructure. In an embodiment, a clad layer doped with a conductive dopant may be formed on the upper and / or lower portions of the active layer 12 along the length of the light emitting device LD. For example, the clad layer may be formed of an AlGaN layer, an InAlGaN layer, a GaAs layer, or the like. According to an embodiment, materials such as AlGaN, InAlGaN, and GaAs may be used to form the active layer 12, but various other materials may also be used to form the active layer 12. The active layer 12 may include a first surface in contact with the first semiconductor layer 11 and a second surface in contact with the second semiconductor layer 13.

[0042] In one embodiment, the color (or emitted light color) of the light-emitting element LD may be determined depending on the wavelength of the light emitted from the active layer 12. The color of such a light-emitting element LD may determine the color of a corresponding pixel. For example, the light-emitting element LD may emit red light, green light, or blue light.

[0043] When an electric field of a specific voltage or more is applied to the ends (for example, both ends) of the light-emitting element LD, electron-hole pairs are recombined in the active layer 12, and the light-emitting element LD can emit light. By controlling the light emission of the light-emitting element LD, the light-emitting element LD can be used as a light source (or a light-emitting source) for various light-emitting devices, including pixels of a display device.

[0044] The second semiconductor layer 13 may be disposed on the second surface of the active layer 12. The second semiconductor layer 13 may include a semiconductor layer of a different type from the first semiconductor layer 11. As an example, the second semiconductor layer 13 may include at least one p-type semiconductor layer. For example, the second semiconductor layer 13 may include a p-type semiconductor layer that includes at least one semiconductor material from the group consisting of InAlGaN, GaN, AlGaN, InGaN, AlN, and InN, and is doped with a dopant of second conductivity (or a p-type dopant) such as Mg, Zn, Ca, Sr, or Ba. However, the material constituting the second semiconductor layer 13 is not limited thereto, and various other materials may also be used to form the second semiconductor layer 13.

[0045] Although the first semiconductor layer 11 and the second semiconductor layer 13 are illustrated as being composed of a single layer, this is not intended to be limiting. In some embodiments, depending on the material of the active layer 12, each of the first semiconductor layer 11 and the second semiconductor layer 13 may further include at least one or more layers, such as a cladding layer and / or a tensile strain barrier reducing (TSBR) layer. The TSBR layer may be a strain relief layer disposed between semiconductor layers with different lattice structures to act as a buffer to reduce the difference in lattice constants. The TSBR layer may be composed of a p-type semiconductor layer such as p-GaInP, p-AlInP, or p-AlGaInP, but is not limited thereto.

[0046] According to an embodiment, the light emitting device LD may further include a contact electrode (hereinafter referred to as a "first contact electrode") disposed on the upper part of the second semiconductor layer 13, in addition to the above-described first semiconductor layer 11, active layer 12, and second semiconductor layer 13. According to another embodiment, the light emitting device LD may further include one other contact electrode (hereinafter referred to as a "second contact electrode") disposed on one end of the first semiconductor layer 11.

[0047] In an embodiment, the light-emitting element LD may further include an insulating film 14 (or an insulating coating). However, depending on the embodiment, the insulating film 14 may be omitted. In another embodiment, the insulating film 14 may be provided so as to cover only a portion of the first semiconductor layer 11, the active layer 12, and the second semiconductor layer 13.

[0048] The insulating film 14 can prevent an electrical short circuit that may occur when the active layer 12 comes into contact with a conductive material other than the first and second semiconductor layers 11 and 13 .

[0049] The insulating film 14 may include a transparent insulating material, and may be formed in the form of a single layer or multiple layers, including a double layer.

[0050] The light emitting device LD described above can be used as a light source (or a light source) of various display devices. The light emitting device LD can be manufactured through a surface treatment process. For example, when the light emitting device LD is mixed with a fluid solution (or solvent) and supplied to each pixel region (e.g., the light emitting region of each pixel or the light emitting region of each sub-pixel), the surface of each light emitting device LD can be treated so that the light emitting device LD is uniformly injected into the solution without uneven aggregation.

[0051] The above-described light-emitting element LD can be used in various types of electronic devices requiring a light source, including a display device. For example, the light-emitting element LD can be used as a light source for a pixel. However, the application field of the light-emitting element LD is not limited to the above example. For example, the light-emitting element LD can also be used in other types of electronic devices requiring a light source, such as a lighting device.

[0052] FIG. 3 is a schematic plan view showing a display device according to an embodiment of the present invention.

[0053] The present invention can be applied to any electronic device having a display surface on at least one side, such as a smartphone, television, tablet PC, videophone, e-book reader, desktop PC, laptop PC, workstation, server, PDA, medical device, camera, or wearable device.

[0054] Referring to Figures 1, 2, and 3, the display device DD may include a substrate SUB, a pixel PXL formed on the substrate SUB and including at least one light-emitting element LD, a driving unit formed on the substrate SUB for driving the pixel PXL, and a wiring unit connecting the pixel PXL and the driving unit.

[0055] The substrate SUB can include a display area DA and a non-display area NDA.

[0056] The display area DA may be an area where pixels PXL that display images are formed, and the non-display area NDA may be an area where drivers and parts of wiring connecting the pixels PXL to the drivers are formed.

[0057] The non-display area NDA may be adjacent to the display area DA and may be formed on at least one side of the display area DA.

[0058] The wiring unit provides signals to the pixels PXL and may include scan lines, data lines, light emission control lines, and fan-out lines connected to each of these lines.

[0059] The substrate SUB may include a transparent insulating material to transmit light, and may be a rigid substrate or a flexible substrate.

[0060] The pixel PXL may be any one of a red pixel, a green pixel, and a blue pixel. A combination of red pixels, green pixels, and blue pixels may be arranged (arranged) on the display area DA. However, this is not limited thereto, and each pixel PXL may emit light in a color other than red, green, and blue. For example, the pixel PXL may emit white light.

[0061] The pixel PXL may include a light-emitting element LD. The light-emitting element LD may have a small size ranging from nanoscale (or nanometer) to microscale (or micrometer). The light-emitting element LD may form a light source for the pixel PXL.

[0062] FIG. 4 is a schematic diagram showing an example of a pixel included in the display device of FIG.

[0063] For convenience of explanation, the circuit configuration of the pixel PXL for driving the light emitting element LD is omitted in Fig. 4. Fig. 4 shows a schematic view of a part of the light emitting area EMA of the pixel PXL.

[0064] 1, 2, and 4, the pixel PXL may include an area defined as a light-emitting area EMA that emits light of a specific color. The light-emitting area EMA can be understood as an area in which a light-emitting element LD is disposed and that emits light of a specific wavelength band.

[0065] The pixel PXL may further include a non-light-emitting region other than the light-emitting region EMA. The non-light-emitting region does not have a light-emitting element LD disposed therein, and light emitted from the light-emitting element LD does not reach the non-light-emitting region, so the non-light-emitting region may be a region from which light is not emitted.

[0066] In one embodiment, the pixel PXL may include a first electrode ELT1, a second electrode ELT2, and a light-emitting element LD.

[0067] The first electrode ELT1 and the second electrode ELT2 may be spaced apart from each other. The first electrode ELT1 and the second electrode ELT2 may be connected (for example, electrically connected) to the light emitting element LD. For example, the first electrode ELT1 may be connected (for example, electrically connected) to a first end EP1 of the light emitting element LD, and the second electrode ELT2 may be connected (for example, electrically connected) to a second end EP2 of the light emitting element LD.

[0068] One of the first electrode ELT1 and the second electrode ELT2 may be an anode electrode of the light emitting element LD, and the other may be a cathode electrode of the light emitting element LD. For example, different power sources may be connected (for example, electrically connected) to the first electrode ELT1 and the second electrode ELT2.

[0069] In an embodiment, the first electrode ELT1 and the second electrode ELT2 may each extend in the second direction DR2 in the light emitting area EMA.

[0070] The first electrode ELT1 and the second electrode ELT2 may be formed as a single film using a single material or a mixture of materials selected from the group consisting of molybdenum (Mo), tungsten (W), aluminum neodymium (AlNd), titanium (Ti), aluminum (Al), silver (Ag), and alloys thereof, or may be formed as a double film or multi-film (stacked film) structure using low-resistance materials such as molybdenum (Mo), titanium (Ti), copper (Cu), aluminum (Al), or silver (Ag) to reduce wiring resistance.

[0071] However, this is merely an example, and the first electrode ELT1 and the second electrode ELT2 may be made of indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO x The transparent conductive material may include at least one of a variety of transparent conductive materials, including indium gallium zinc oxide (IGZO), indium tin zinc oxide (ITZO), and the like.

[0072] The light-emitting element LD may be disposed between the first electrode ELT1 and the second electrode ELT2. In one embodiment, a first end EP1 of the light-emitting element LD may be in contact (for example, direct contact) with the first electrode ELT1, and a second end EP2 of the light-emitting element LD may be in contact (for example, direct contact) with the second electrode ELT2. In another embodiment, the first end EP1 of the light-emitting element LD may be connected (for example, electrically connected) to the first electrode ELT1 via a separate first contact electrode, and the second end EP2 of the light-emitting element LD may be connected (for example, electrically connected) to the second electrode ELT2 via a separate second contact electrode.

[0073] The light emitting elements LD may be spaced apart from one another. For example, the light emitting elements LD may be aligned parallel to one another within the light emitting area EMA. The distance at which the light emitting elements LD are spaced apart is not limited.

[0074] In one embodiment, the light emitting element LD may have a shape extending in the first direction DR1, however, this is merely an example and the light emitting element LD may be disposed obliquely with respect to the first direction DR1.

[0075] The light emitting element LD may have a diameter D and / or length on the order of nanoscale to microscale. For example, the light emitting element LD may have a rod shape, a bar shape, or a column shape that is long in the length direction.

[0076] In a conventional method for manufacturing a display device, ink in which light emitting elements LD, which are bipolar elements, are dispersed is sprayed onto a substrate on which electrodes such as a first electrode ELT1 and a second electrode ELT2 are formed, and electric signals are applied to the electrodes to align the light emitting elements LD. For example, a dielectrophoretic force is transmitted to the light emitting elements LD by an electric field generated by the electric signal applied to the electrodes, and the orientation and position of the light emitting elements LD are controlled, so that each of the light emitting elements LD can be aligned on the first electrode ELT1 and the second electrode ELT2.

[0077] However, during the ink ejection process, a portion of the light emitting element LD included in the ink INK may be provided in a space where the first electrode ELT1 and the second electrode ELT2 are not disposed. For example, at least a portion of the light emitting element LD may be in contact with a lower insulating layer (e.g., a dielectric layer) exposed from the first electrode ELT1 and the second electrode ELT2.

[0078] For example, an attractive force such as van der Waals force may occur between the light emitting element LD and the first and second electrodes ELT1 and the underlying structure of the ELT (e.g., a dielectric layer) in contact therewith. If such an attractive force affects the dielectrophoretic force, the light emitting element LD may not move or may not be aligned to a specific position. A light emitting element LD that is not properly aligned on the first electrode ELT1 and the second electrode ELT2 may not emit light with the desired brightness, which may cause defects in the display device DD.

[0079] Therefore, a display device manufacturing apparatus and a display device manufacturing method according to an embodiment of the present invention for improving the alignment reliability and manufacturing yield of the light emitting device LD will be described in detail.

[0080] FIG. 5 is a schematic diagram showing an apparatus for manufacturing a display device according to an embodiment of the present invention.

[0081] 5, a first direction DR1, a second direction DR2, and a third direction DR3 are defined. The first direction DR1 and the second direction DR2 are located on the same plane and are perpendicular to each other, and the third direction DR3 is perpendicular to the first direction DR1 and the second direction DR2.

[0082] 5, for the sake of convenience, each component of the manufacturing apparatus 1000 is simply illustrated. Each component may be realized in various known shapes, positional relationships, etc., to match the actual manufacturing method and operation.

[0083] 4 and 5, a manufacturing apparatus 1000 for a display device DD may include a stage 100, a mold 200, a coating device 300, a doctor blade 400, and a pressure applying device 500 (for example, a bonding device). The manufacturing apparatus 1000 may further include a drying device 600.

[0084] The stage 100 may provide an area on which the substrate SUB of the display device DD is disposed. The substrate SUB may be placed and fixed on the stage 100. The stage 100 may be fixed or movable depending on the process method. For example, in the process of bonding (butting) the mold 200 and the substrate SUB, the stage 100 may be inverted so that the top surface of the substrate SUB faces the bottom surface (or lower surface).

[0085] The mold 200 may have a surface including recessed portions RP. The recessed portions RP may be formed on one surface of the mold 200 to correspond to the arrangement of the light emitting devices LD. The mold 200 may include materials such as metal, ceramic, and plastic.

[0086] In one embodiment, each of the recessed portions RP may be filled with at least one light emitting element LD. The recessed portions RP may be arranged in a first direction DR1 and a second direction DR2. For example, the recessed portions RP may be arranged in accordance with the arrangement of the light emitting elements LD on the substrate SUB. In other words, the recessed portions RP may determine the arrangement of the light emitting elements LD on the substrate SUB.

[0087] Each of the recesses RP can be filled with at least one light emitting element LD.

[0088] The coating device 300 can coat, spray, or inject ink in which the light emitting elements LD are dispersed onto the surface of the mold 200. The coating device 300 can be spaced apart from the mold 200 by a specific distance.

[0089] In one embodiment, the applicator 300 can move in the first direction DR1 and / or the second direction DR2 and spray ink INK onto the mold 200. However, this is merely an example, and the applicator 300 may spray ink INK while remaining stationary, and the ink INK may be applied to the surface of the mold 200 as the mold 200 moves.

[0090] The ink INK may include a solvent SOL and the light-emitting element LD contained in the solvent SOL. For example, the ink INK may further include a dispersant for uniformly dispersing the light-emitting element LD in the solvent SOL. The solvent SOL contained in the ink INK may be in a liquid or colloidal state.

[0091] The solvent SOL may include acetone, water, alcohol, toluene, propylene glycol (PG), or propylene glycol methyl acetate (PGMA), or the like. However, this is merely an example, and the solvent SOL may be PGME (Propylene Glycol Methyl Ether), DGME (Dipropylene Glycol Methyl Ether), TGME (Tripropylene Glycol Methyl Ether), PGMEA (Propylene Glycol Methyl Ether Acetate), DGMEA (Dipropylene Glycol Methyl Ether Acetate), PGPE (Propylen Glycol n-Propyl Ether), DGPE (Dipropylen Glycol n-Propyl Ether), PGBE (Propylen Glycol n-Butyl Ether), DGBE (Dipropylen Glycol n-Butyl Ether), or the like. Dipropylene Glycol n-Butyl Ether), TGBE (Tripropylen Glycol n-Butyl Ether), PGPE (Propylen Glycol Phenyl Ether), PGD (Propylene Glycol Diacetate), DGDE (Dipropylen Glycol Dimethyl Ether), DGEE (Diethylene Glycol Ethyl Ether)Diethylene glycol ethyl ether), DGME (Diethylne Glycol Methyl Ether), DGBE (Diethylne Glycol n-Butyl Ether), DGHE (Diethylne Glycol Hexyl Ether), DGBEA (Diethylne Glycol n-Butyl Ether Acetate), EGPE (Ethylene Glycol Propyl Ether), EGBE (Ethylene Glycol n-Butyl Ether), EGHE (Ethylene Glycol Hexyl Ether), EGBEA (Ethylene Glycol n-Butyle Ether Acetate), TGME (Triethylene Glycol Methyl Ether), The polymer may include at least one of triethylene glycol methyl ether (TGEE), triethylene glycol ethyl ether (TGBE), triethylene glycol n-butyl ether (TGBE), ethylene glycol phenyl ether (EGPE), and ethylene glycol n-butyl ether mixture (EGBEM);

[0092] In one embodiment, the applicator 300 may be implemented as an inkjet printing module, a dispensing module, a slit coating module, or the like. For example, the applicator 300 may use a printhead to apply, spray, or inject ink onto the mold 200. However, this is merely an example, and the applicator 300 is not limited thereto. For example, the applicator 300 may be replaced with an immersion device that immerses the surface of the mold 200 in ink INK.

[0093] The doctor blade 400 can remove the ink INK applied to the area other than the recessed portion RP of the mold 200. The doctor blade 400 can have a thin plate shape made of metal or resin.

[0094] The doctor blade 400 can be brought into contact with the surface of the mold 200 and moved in one direction with a specific contact pressure. The doctor blade 400 can push the ink INK containing the light-emitting elements LD into the recessed portions RP while simultaneously scraping off the ink INK from portions other than the recessed portions RP. For example, the doctor blade 400 can leave the ink INK disposed within the recessed portions RP and remove the ink INK disposed on the surface of the mold 200. A series of processes using such a doctor blade 400 can include a doctor blade process.

[0095] In one embodiment, the length of the doctor blade 400 in the second direction DR2 may correspond to the length of the mold 200 in the second direction DR2. For example, the doctor blade 400 may contact the surface of the mold 200 and move in the first direction DR1 or the opposite direction. For example, the contact pressure between the doctor blade 400 and the mold 200 may be determined (controlled) so that the doctor blade 400 contacts only the surface of the mold 200 excluding the recessed portion RP.

[0096] However, this is merely an example, and the material, shape, movement direction, scraping contact pressure, angle, etc. of the doctor blade 400 can be determined depending on conditions such as the properties, viscosity, and material of the mold 200.

[0097] The pressure applying device 500 can bond the surface of the mold 200 (for example, the upper surface including the recessed portion RP) onto the substrate SUB. The pressure applying device 500 can be located on the rear surface of the mold 200, and by applying pressure to the mold 200 while the mold 200 and the substrate SUB are in contact with each other, the ink INK in the recessed portion RP and the light-emitting element LD contained therein can fall onto the substrate SUB.

[0098] The drying device 600 can evaporate and remove the solvent SOL of the ink INK remaining on the surface of the mold 200 or the solvent SOL of the ink INK remaining on the substrate SUB. In one embodiment, the drying device 600 can include a light source for evaporating the solvent SOL. For example, the light source can be an infrared lamp or an infrared irradiation device. However, this is merely an example, and the light source can also be a lamp or light irradiation device that irradiates visible light or ultraviolet light.

[0099] In one embodiment, the light emitting element LD filled in the recess portion RP may be exposed when the solvent SOL contained in the ink INK on the mold 200 is removed. In another embodiment, the light emitting element LD on the first and second electrodes ELT1 and ELT2 may be exposed when the solvent SOL contained in the ink INK on the substrate SUB is removed.

[0100] FIG. 6a is a schematic cross-sectional view showing an example of a part of a mold included in the manufacturing apparatus of FIG. 5, and FIG. 6b is a schematic plan view showing an example of a part of the mold of FIG. 6a.

[0101] 4, 5, 6a and 6b, the surface of the mold 200 may include recesses RP.

[0102] The recess portion RP can determine the position where the light emitting element LD is disposed / arranged on the substrate SUB. For example, the light emitting element LD can be disposed on the substrate SUB corresponding to (or overlapping) the position of the recess portion RP. The width W, length R_L, and depth H of the recess portion RP can be determined based on the size of the light emitting element LD. For example, the recess portion RP can be designed (or formed) to have a space therein large enough for the light emitting element LD to be disposed in a lying position.

[0103] For convenience of explanation, Figure 6a shows a first recess portion RP1 that is not filled with ink INK and a second recess portion RP2 that is filled with ink INK containing a light-emitting element LD and a solvent SOL. The shapes of the first recess portion RP1 and the second recess portion RP2 may be substantially the same. Unless otherwise specified, the description of the recess portion RP can be understood to equally apply to the first recess portion RP1 and the second recess portion RP2.

[0104] In one embodiment, the depth H of the recess portion RP may be greater than the diameter D of the light emitting element LD. Therefore, the light emitting element LD disposed lying down in the recess portion RP does not protrude from the recess portion RP. If a part of the light emitting element LD protrudes from the recess portion RP, excessive friction or impact may be applied to the light emitting element LD during the doctor blade process, which may cause damage and / or defects to the light emitting element LD.

[0105] Since the diameter D of the light-emitting element LD may not be uniform, the depth H of the recess portion RP may be determined based on the maximum diameter D of the light-emitting element LD that is actually used. For example, the diameter D of the light-emitting element LD may be understood to be the light-emitting element LD or the maximum diameter D of the light-emitting element LD.

[0106] In one embodiment, the depth H of the recess portion RP may be less than about 1.5 times the diameter D of the light-emitting element LD. If the depth H of the recess portion RP is about 1.5 times or more the diameter D of the light-emitting element LD, the light-emitting element LD may unintentionally accumulate in the recess portion RP. To prevent such accumulation of the light-emitting element LD, the depth H of the recess portion RP may be less than about 1.5 times the diameter D of the light-emitting element LD.

[0107] In one embodiment, the recess portion RP may include an alignment hole ARH and a step portion STP including a step side surface STS and a step bottom surface STL. The step portion STP may be distinguished (or defined) from the alignment hole ARH by a difference in height between the alignment hole ARH and the step portion STP. The alignment hole ARH may be a portion where the light emitting device LD is actually filled or disposed.

[0108] 6b, the length R_L of the alignment hole ARH in the first direction DR1 may be longer than the length L of the light emitting element LD. For example, since the length of the light emitting element LD may not be uniform, the length L of the light emitting element LD may be the maximum length of the actual lengths of the light emitting element LD.

[0109] If the length R_L of the alignment hole ARH is less than twice the length L of the light emitting element LD, only one light emitting element LD can be filled in the alignment hole ARH, as shown in Fig. 6a. If the length R_L of the alignment hole ARH is greater than or equal to twice the maximum length L1 of the light emitting element LD, two or more light emitting elements LD can be aligned in the first direction DR1 within the alignment hole ARH.

[0110] 6a, the width W of the alignment hole ARH in the second direction DR2 may be greater than the diameter D of the light emitting element LD and less than about 1.5 times the diameter D of the light emitting element LD. Therefore, only one light emitting element LD may be disposed in the alignment hole ARH based on the second direction DR2.

[0111] In one embodiment, the depth H1 of the alignment hole ARH may be greater than the radius (e.g., D / 2) of the light emitting element LD and less than or equal to the diameter D of the light emitting element LD. Therefore, the light emitting element LD properly filled or positioned in the alignment hole ARH may not be released out of the alignment hole ARH during the doctor blade process.

[0112] In one embodiment, the bottom surface (or lower surface) of the alignment hole ARH may be flat. For example, as shown in FIG. 6a, the cross section of the alignment hole ARH may have a rectangular shape. However, this is merely an example, and the cross-sectional shape of the alignment hole ARH is not limited thereto. The cross-sectional shape of the alignment hole ARH may be designed (or formed) in various ways depending on the shape of the light emitting device LD, etc.

[0113] The step portion STP of the recess portion RP can help align the light emitting element LD within the recess portion RP. For example, the depth H2 of the step portion STP (or the height of the step side surface STS) may be smaller than the radius of the light emitting element LD. This may facilitate removal of the light emitting element LD by the doctor blade 400 when the light emitting element LD is provided on the step portion STP.

[0114] For example, as shown in FIG. 6a, the light-emitting element LD_R that is first supplied by the coating apparatus 300 can be disposed on the step surface STP of the second recess portion RP2.

[0115] At this time, the doctor blade 400 may move while contacting only the surface of the mold 200, excluding the recess portion RP including the first and second recess portions RP1 and RP2. When the doctor blade 400 moves in the second direction DR2 while contacting the mold 200, the supplied light emitting device LD_R may exceed the step portion STP (for example, the step lower surface STL) and be removed from the second recess portion RP2. As described above, because the depth H2 of the step portion STP is smaller than the radius of the light emitting device LD, the supplied light emitting device LD_R disposed on the step portion STP (for example, the step lower surface STL) may be easily removed from the step portion STP (for example, the step lower surface STL) by the movement of the doctor blade 400.

[0116] For example, the doctor blade 400 may contact the mold 200 and move in the opposite direction of the second direction DR2. If no light emitting element LD is disposed in the alignment hole ARH of the second recess portion RP2, the supplied light emitting element LD_R may fall (or move) into the alignment hole ARH of the second recess portion RP2 as the doctor blade 400 moves, thereby filling the alignment hole ARH of the second recess portion RP2. If a light emitting element LD is disposed in the alignment hole ARH of the second recess portion RP2, the supplied light emitting element LD_R may move beyond the second recess portion RP2 to the first recess portion RP1. Because the ink INK is in a solution or colloidal state, it may prevent, mitigate, or minimize friction / collision between the supplied light emitting elements LD_R and / or impact and damage to the supplied light emitting elements LD_R due to friction between the mold 200 and the supplied light emitting elements LD_R during the doctor blade process.

[0117] In this manner, the light emitting elements LD can be aligned on the mold 200 according to the recessed portions RP arranged periodically or non-periodically on the mold 200 .

[0118] 7 to 12 are schematic cross-sectional views showing other examples of a part of the mold included in the manufacturing apparatus of FIG.

[0119] 7 to 12, the same or similar components as those described with reference to Figures 6a and 6b are designated by the same reference numerals, and redundant description will be omitted. The molds 200a, 200b, 200c, 200d, 200e, and 200f in Figures 7 to 12 may be substantially the same as or similar to the recessed portions RP in Figures 6a and 6b, except for the cross-sectional shape of the recessed portions RP.

[0120] 4, 5, 7 to 12, each of the molds 200a, 200b, 200c, 200d, 200e, and 200f may include a recessed portion RP, which may be deformed into various cross-sectional shapes.

[0121] In one embodiment, the depth H of the recess portion RP may be greater than the diameter D of the light-emitting element LD and less than about 1.5 times the diameter D of the light-emitting element LD.

[0122] In one embodiment, as shown in FIG. 7, the recess portion RP may include an alignment hole ARH that may be filled with at least one light emitting element LD, and a step portion STP that is separated from (or adjacent to) the alignment hole ARH.

[0123] The step portion STP of the recess portion RP (for example, the step side surface STS and the step bottom surface STL) can help align the light emitting element LD within the recess portion RP. For example, the step depth H2 may be smaller than the radius of the light emitting element LD. As a result, when the light emitting element LD is provided on the step portion STP (for example, the step bottom surface STL), the light emitting element LD can be easily removed by the doctor blade 400.

[0124] The light emitting device LD may be disposed in the alignment hole ARH in a substantially horizontal state. In one embodiment, as shown in FIGS. 7 and 9, the bottom surface (lower surface) of the alignment hole ARH of the molds 200a and 200c may include a curved surface. The curved surface of the bottom surface (lower surface) may be similar to a portion of the outer periphery of the light emitting device LD. This may reduce the fluidity of the light emitting device LD in the alignment hole ARH.

[0125] 8, 9, and 10, the recessed portions RP of the molds 200b, 200c, and 200d may include alignment holes ARH and inclined surfaces IS that separate the alignment holes ARH. The bottom surfaces (lower surfaces) of the alignment holes ARH may be flat (as shown in FIGS. 8 and 10) or curved (as shown in FIG. 9).

[0126] The inclined surface IS can facilitate the movement of the light-emitting element LD into the alignment hole ARH and the removal of the light-emitting element LD. For example, in a coating process of ink containing the light-emitting element LD, the light-emitting element LD supplied onto the inclined surface IS can be easily introduced into the alignment hole ARH by the inclined surface IS. For example, in a doctor blade process, the movement of the light-emitting element LD can be facilitated via the inclined surface IS.

[0127] In one embodiment, the first recessed portion RP1 and the second recessed portion RP2 of the molds 200a, 200b, 200c, and 200e may be spaced apart from each other as shown in Figures 7, 8, 9, and 11. In another embodiment, the first recessed portion RP1 and the second recessed portion RP2 may be formed continuously in the second direction DR2 as shown in Figures 10 and 12. The distance, size, etc. between the first and second recessed portions RP1 and RP2 may be determined depending on the arrangement of the light emitting elements LD.

[0128] 11 and 12, the recess portion RP may include an alignment hole ARH having an inclined surface SP. The depth H of the alignment hole ARH may be substantially the same as the depth H of the recess portion RP. When viewed from the first direction DR1, only one light emitting device LD may be filled in the recess portion RP. The light emitting device LD to be removed, which is supplied to the second recess portion RP2, may be moved out of the second recess portion RP2 by a doctor blade process.

[0129] FIG. 13 is a schematic diagram showing another example of the manufacturing apparatus for the display device of FIG.

[0130] 13, the same or similar components as those described with reference to FIG. 5 are designated by the same reference numerals, and redundant description will be omitted. The manufacturing apparatus 1000A of the display device of FIG. 13 may be substantially the same as or similar to the manufacturing apparatus 1000 of the display device DD of FIG. 5, except for the first vibration device 700.

[0131] 4 and 13, the manufacturing apparatus 1000A for the display device DD may include a stage 100, a mold 200, a coating device 300, a doctor blade 400, a pressure applying device 500, a drying device 600, and a first vibrating device 700.

[0132] In one embodiment, the first vibrating device 700 can vibrate the mold 200 on which the ink INK is applied. The first vibrating device 700 can be connected to the pressure applying device 500 connected to the mold 200. The first vibrating device 700 can vibrate the mold 200 via the pressure applying device 500. Alternatively, the first vibrating device 700 can be connected to the mold 200 (for example, directly connected) and vibrate the mold 200.

[0133] In one embodiment, the first vibrating device 700 can generate sound waves or ultrasonic waves to vibrate the mold 200. For example, the first vibrating device 700 can include a sound wave vibrator or an ultrasonic vibrator. The vibration of the mold 200 can change the positions and / or orientations of the light-emitting elements LD contained in the ink INK disposed on the mold 200. As a result, at least one of the light-emitting elements LD can be filled or positioned in each recess portion RP.

[0134] However, this is merely an example, and the first vibrating device 700 is not limited to this. For example, the first vibrating device 700 itself may vibrate slightly at a specific frequency, causing the pressure application device 500 and / or the mold 200 in contact with it to vibrate slightly.

[0135] This allows most of the light emitting elements LD to be pre-aligned before the doctor blade process, improving the accuracy of the alignment.

[0136] FIG. 14 is a schematic diagram showing yet another example of the manufacturing apparatus for the display device of FIG.

[0137] 14, components that are the same as or similar to those described with reference to FIG. 5 are designated by the same reference numerals, and redundant description will be omitted. The manufacturing apparatus 1000B of the display device DD of FIG. 14 may be substantially the same as or similar to the manufacturing apparatus 1000 of the display device DD of FIG. 5, except for the electric field application apparatus 800.

[0138] 4 and 14, the manufacturing apparatus 1000B of the display device DD may include a stage 100, a mold 200, a coating device 300, a doctor blade 400, a pressure applying device 500, a drying device 600, and an electric field applying device 800.

[0139] In one embodiment, the electric field applying device 800 may apply an electric field onto the substrate SUB to fix the position of the light emitting device LD. For example, the electric field applying device 800 may include a first probe unit 820 connected to one side of the substrate SUB (for example, electrically and physically connected to the first side), and a second probe unit 840 connected to the other side opposite the one side of the substrate SUB (for example, electrically and physically connected to the second side).

[0140] The first probe unit 820 and the second probe unit 840 may include probe pads that transmit electrical signals. The probe pads of the first probe unit 820 may be connected (for example, electrically connected) to pads or electrodes provided on one side of the substrate SUB, and the probe pads of the second probe unit 840 may be connected (for example, electrically connected) to pads or electrodes disposed on the other side of the substrate SUB. Although FIG. 14 schematically illustrates the first and second probe units 820 and 840 as being in the shape of plates disposed on both sides of the substrate SUB, this is merely an example, and the shapes and arrangements of the first and second probe units 820 and 840 are not limited thereto.

[0141] The electric field applying device 800 provides an electric signal to the first and second probe units 820 and 840, and the probe pads can form an electric field on the substrate SUB through the electric signal. Such an electric signal can be an AC voltage.

[0142] The light emitting element LD is subjected to a dielectrophoretic force due to the electric field, and while the electric field is applied, the position / orientation of each element can be fixed depending on the magnitude and direction of the dielectrophoretic force.

[0143] The electric field application operation of the electric field application device 800 can be performed during the process of separating the mold 200 and the substrate SUB. In one embodiment, before separating the mold 200 and the substrate SUB, the electric field application device 800 is operated to prevent misalignment and separation due to movement / rotation of the light emitting device LD, and the mold 200 and the substrate SUB can be separated with an electric field applied on the substrate SUB.

[0144] Therefore, it is possible to prevent or reduce separation or misalignment of the light emitting device LD that may occur during the process of separating the mold 200 from the substrate SUB.

[0145] In one embodiment, the manufacturing apparatus 1000B of the display device DD may further include the first vibration device 700 described with reference to FIG.

[0146] FIG. 15 is a schematic diagram showing yet another example of the manufacturing apparatus 1000C for the display device DD of FIG.

[0147] 15, the same or similar components as those described with reference to FIGS. 5 and 14 are designated by the same reference numerals, and redundant description will be omitted. The manufacturing apparatus 1000C of the display device DD in FIG. 15 may be substantially the same as or similar to the manufacturing apparatus 1000B of the display device DD in FIG. 14, except for the second vibration device 900.

[0148] Referring to Figures 5 and 15, the manufacturing apparatus 1000C for the display device DD may include a stage 100, a mold 200, a coating device 300, a doctor blade 400, a pressure applying device 500, a drying device 600, an electric field applying device 800, and a second vibrating device 900.

[0149] In one embodiment, the second vibration device 900 is capable of vibrating the substrate SUB. The second vibration device 900 may be coupled to the substrate SUB and / or the stage 100 supporting the substrate SUB.

[0150] In one embodiment, the second vibration device 900 can generate sound waves or ultrasonic waves to vibrate the substrate SUB. For example, the second vibration device 900 can include a sonic vibrator or an ultrasonic vibrator.

[0151] When the mold 200 and the substrate SUB are separated, the second vibrating device 900 can vibrate the substrate SUB. For example, the second vibrating device 900 can assist in the process of separating the mold 200 and the substrate SUB. For example, the vibration by the second vibrating device 900 can facilitate the separation of the mold 200 and the substrate SUB, and the separation of the mold 200 and the ink INK (e.g., the solvent SOL of the ink INK). In this case, the force transmitted to the light emitting element LD by the vibration may be smaller than the dielectrophoretic force caused by the electric field. Therefore, the mold 200 and the substrate SUB can be easily separated without fluctuations in the position and orientation of the light emitting element LD due to vibration of the substrate SUB.

[0152] In one embodiment, the manufacturing apparatus 1000C of the display device DD may further include the first vibrating device 700 described with reference to FIG.

[0153] 16 to 25 are schematic diagrams illustrating a method for manufacturing a display device according to an embodiment of the present invention.

[0154] Referring to Figures 16 to 25, a method for manufacturing a display device DD includes applying ink INK in which light-emitting elements LD are dispersed to the surface of a mold 200 including a recess portion RP, removing the ink INK applied to the part of the mold 200 other than the recess portion RP using a doctor blade 400, bonding the mold 200 to a substrate SUB of the display device DD to provide light-emitting elements LD on electrodes ETL1 and ETL2 formed on the substrate, and separating the mold 200 from which the light-emitting elements LD have been separated from the substrate SUB.

[0155] 16 and 17, ink INK can be applied to the surface of the mold 200 using an application device 300. In one embodiment, the application device 300 can spray or apply ink INK to the surface of the mold 200 while moving in a first direction DR1. However, this is merely an example, and the movement direction of the application device 300 is not limited thereto. For example, the movement of the application device 300 may be fixed, and ink INK may be applied to the mold 200 while the mold 200 moves in a specific direction.

[0156] The ink INK can be applied onto the mold 200 by various process methods, such as an inkjet printing method, a dispensing method, a coating method such as slit coating, or a dipping method.

[0157] 17, the ink INK may include a fluid solvent SOL and light-emitting elements LD dispersed in the solvent SOL. The solvent SOL may be in a liquid or colloidal state. The solvent SOL may be uniformly applied onto the surface of the mold 200 including the first recessed portion RP1 and the second recessed portion RP2. The light-emitting elements LD may be randomly provided on the surface of the mold 200.

[0158] For example, a part of the light emitting element LD may be disposed in the alignment hole ARH, and another part of the light emitting element LD may be disposed on the step portion STP of the recess portion RP (for example, the step side surface STS and the step bottom surface STL). For example, still another part of the light emitting element LD may be disposed on the surface of the mold 200 other than the recess portion RP, and the shape in which the light emitting element LD is disposed may also vary.

[0159] For example, the cross-sectional shape of the mold 200 in Figure 17 is illustrative and not limiting, and the cross-section of the mold 200 can be designed (or formed) in various shapes, for example, as described with reference to Figures 7-12.

[0160] Then, a portion of the ink INK on the mold 200 may be removed. In one embodiment, as shown in Figures 18 to 23, the mold 200 may be vibrated using a first vibrating device 700 to fill at least a portion of the light emitting elements LD in the recesses RP (see Figures 18 and 19), the surface of the mold 200 may be scraped with a doctor blade 400 to align the light emitting elements LD on the mold 200 (see Figures 20 and 21), and the surface of the mold 200 may be irradiated with light to remove the solvent SOL of the ink INK remaining on the surface of the mold 200 (see Figures 22 and 23).

[0161] 18 and 19, the first recessed portion RP1 and the second recessed portion RP2 may be filled with light emitting elements LD by vibrating the mold 200 using the first vibrating device 700. For example, the light emitting elements LD arranged on the stepped portion STP may fall into the alignment holes ARH. In this way, the mold 200 may be vibrated so that all of the recessed portions RP are filled with the light emitting elements LD. In one embodiment, the first vibrating device 700 may include a sonic vibrator or an ultrasonic vibrator.

[0162] According to the embodiment, as shown in FIG. 19, some of the light emitting elements LD may remain on the surface of the mold 200 that is not covered by the alignment holes ARH.

[0163] According to an embodiment, the mold vibration step of FIG. 18 may be omitted.

[0164] 20 and 21, the surface of the mold 200 can be scraped with a doctor blade 400 to align the light emitting elements LD within the alignment holes ARH (see FIG. 19). The doctor blade 400 can move in one direction (e.g., a first direction DR1) with a specific contact pressure while in contact with a portion of the surface of the mold 200.

[0165] The light emitting device LD disposed in the portion other than the alignment hole ARH may be removed together with the solvent SOL.

[0166] 22 and 23, in one embodiment, the solvent SOL (shown in FIG. 21) of the ink INK remaining on the surface of the mold 200 can be removed by light irradiation from a drying device 600. For example, the solvent SOL can be completely evaporated by the drying device 600. As a result, only the light-emitting elements LD disposed or fixed in the recessed portions RP remain in the mold 200.

[0167] Then, as shown in FIG. 24, the mold 200 and the substrate SUB may be bonded together, and the light-emitting element LD may be disposed on the electrodes ELT1 and ELT2 (shown in FIG. 25) formed on the substrate SUB. First, as shown in FIG. 24, the substrate SUB and the stage 100 may be aligned or placed in an inverted state on the mold 200, which is placed so that the recessed portion RP faces the third direction DR3. With the substrate SUB and the stage 100 in an inverted state, the mold 200 and the substrate SUB may be bonded together. With the mold 200 and the substrate SUB bonded together, the stage 100, the substrate SUB, the mold 200, and the pressure application device 500 may be inverted again. This allows the positions of the stage 100, the substrate SUB, the mold 200, and the pressure application device 500 to be created as shown in FIG. For example, with the mold 200 and the pressure application device 500 in an inverted state, a specific pressure may be applied via the pressure application device 500 in the opposite direction of the third direction DR3.

[0168] As a result, the light emitting element LD falls out of the recess portion RP and can be placed on the electrodes ELT1 and ELT2 of the substrate SUB.

[0169] 25, the mold 200 from which the light-emitting elements LD have been separated may be separated from the substrate SUB. In one embodiment, the mold 200 may be lifted or moved in a third direction DR3. The light-emitting elements LD may be arranged on the first electrodes ELT1 and the second electrodes ELT2 in accordance with the arrangement of the recessed portions RP of the mold 200.

[0170] For example, the light emitting element LD can be arranged on the first electrode ELT1 and the second electrode ELT2 in an aligned state due to the arrangement of the recessed portions RP of the mold 200. Therefore, misalignment of the light emitting element LD can be minimized or significantly reduced, thereby reducing product defects and improving alignment reliability and manufacturing yield.

[0171] FIG. 26 is a schematic view showing an example of a step of separating the substrate and mold shown in FIG.

[0172] Referring to FIG. 26, the separated mold 200 of the light emitting device LD can be separated from the substrate SUB.

[0173] In one embodiment, an electric field is applied to the substrate SUB by the electric field application device 800, and the light emitting element LD is fixed on the first electrode ELT1 and the second electrode ELT2, and in this state, the mold 200 can be moved in the third direction DR3 and separated from the substrate SUB.

[0174] The light emitting elements LD are subjected to a dielectrophoretic force due to the electric field, and their positions / orientations can be fixed on the substrate SUB while the electric field is applied. This can prevent or reduce separation or misalignment of the light emitting elements LD that may occur during separation of the mold 200 and the substrate SUB. This can further improve process reliability.

[0175] FIG. 27 is a schematic view showing another example of the step of separating the substrate and the mold in FIG.

[0176] Referring to FIG. 27, the separated mold 200 of the light emitting device LD can be separated from the substrate SUB.

[0177] In one embodiment, an electric field is applied to the substrate SUB using an electric field application device 800, the light emitting element LD is fixed on the first electrode ELT1 and the second electrode ELT2, and vibration is applied to the substrate SUB by a second vibration device 900. In this state, the mold 200 can move in the third direction DR3 and be separated from the substrate SUB.

[0178] The second vibrating device 900 can assist in the process of separating the mold 200 from the substrate SUB. Vibration by the second vibrating device 900 can facilitate separation of the mold 200 from the substrate SUB and separation of the mold 200 from the ink INK (e.g., the solvent SOL of the ink INK). The operation of the second vibrating device 900 has been described above with reference to FIG. 15, so a repeated description will be omitted.

[0179] FIG. 28 is a schematic diagram showing an example of a process for removing the ink solvent.

[0180] 25 and 28, after the mold 200 is separated from the substrate SUB, the solvent S0L of the ink INK remaining on the surface of the substrate SUB can be completely removed by irradiating light onto the substrate SUB.

[0181] Also, in one embodiment, the process of removing ink INK remaining on the mold 200 described with reference to Figures 22 and 23 may be replaced with the process of Figure 28 of removing ink INK remaining on the substrate SUB after separation of the mold 200 and the substrate SUB.

[0182] As described above, the display device DD manufacturing apparatuses 1000, 1000A, 1000B, and 1000C and display device DD manufacturing methods according to the embodiments of the present invention can provide pre-aligned light emitting elements LD on the electrodes ELT1 and ELT2 of the substrate SUB by utilizing the arrangement of the recessed portions RP of the mold 200. Therefore, misalignment of the light emitting elements LD is significantly reduced, which in turn reduces product defects and improves alignment reliability and manufacturing yield.

[0183] Although the present invention has been described with reference to exemplary embodiments, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the following claims.

Claims

1. a stage on which a substrate of the display device is placed; a mold including a surface including recessed portions; an applicator that applies ink containing a light-emitting element to the surface of the mold; a doctor blade that removes the ink disposed on the surface of the mold while leaving the ink disposed in the recessed portion of the mold; a bonding device for bonding the surface of the mold to the substrate; a depth of each of the recessed portions is greater than a diameter of each of the light emitting elements; the depth of each of the recesses is less than about 1.5 times the diameter of each of the light emitting elements; Each of the recessed portions is an alignment hole filled with one of the light emitting elements; a step portion located on both sides of the alignment hole in a width direction thereof and having a depth smaller than that of the alignment hole; The length of the alignment hole in the first direction is longer than the length of each of the light emitting elements; a width of the alignment hole in a second direction intersecting with the first direction is greater than the diameter of the alignment hole; the width of the alignment hole in the second direction is less than about 1.5 times the diameter; a first depth from a bottom of the step portion to a bottom of the alignment hole is greater than a width of the alignment hole in a second direction; The recessed portions are arranged in the first direction and the second direction, The recessed portions are disposed on the substrate in a manner corresponding to the arrangement of the light emitting elements.

2. A display device manufacturing apparatus as described in Claim 1, wherein the step portion has a uniform depth in each of the recess portions.

3. A manufacturing apparatus for a display device as described in Claim 1, wherein the step portion forms an inclined surface by becoming deeper toward the alignment hole in each of the recess portions.

4. 2. The display device manufacturing apparatus according to claim 1, wherein the doctor blade scrapes off the ink in one direction on the surface of the mold, thereby arranging the light-emitting elements in accordance with the alignment pattern of the recessed portions.

5. The apparatus of claim 1 , wherein a bottom surface of the alignment hole is flat.

6. The apparatus of claim 1 , wherein a lower surface of the alignment hole includes a curved surface or an inclined surface.

7. The display device manufacturing apparatus according to claim 1 , further comprising a drying device that evaporates and removes the solvent of the ink remaining on the surface of the mold or the surface of the substrate.

8. The display device manufacturing apparatus according to claim 7 , further comprising a vibration device that vibrates the substrate or the mold on which the ink is applied.

9. The display device manufacturing apparatus according to claim 8 , wherein the vibration device generates sound waves or ultrasonic waves to vibrate the mold, and the vibration device fills at least one of the light-emitting elements into each of the recessed portions.

10. The display device manufacturing apparatus according to claim 8 , wherein the vibration device vibrates the substrate when the mold and the substrate are separated.

11. The display device manufacturing apparatus according to claim 7 , further comprising an electric field applying device that applies an electric field to the substrate to fix the positions of the light emitting elements when the mold and the substrate are separated.

12. applying ink containing a light-emitting element to a surface of the mold including the recess; using a doctor blade to remove the ink disposed on the surface of the mold while leaving the ink disposed in the recessed portion of the mold; bonding the mold to a substrate of a display device, and disposing the light-emitting element on an electrode formed on the substrate; and separating the mold from the substrate after the light-emitting element has been separated. The recessed portion is an alignment hole having a width corresponding to a diameter of the light emitting device; and step portions, each of which is located on either side of the alignment hole in the width direction and has a depth smaller than that of the alignment hole, A method for manufacturing a display device, wherein a first depth from a bottom of the step portion to a bottom of the alignment hole is smaller than a diameter of the light emitting element, and a depth of the recess portion is larger than the diameter of the light emitting element.

13. A method for manufacturing a display device as described in Claim 12, wherein the step portion has a uniform depth in each of the recess portions.

14. A method for manufacturing a display device as described in Claim 12, wherein the step portion forms an inclined surface by becoming deeper toward the alignment hole in each of the recess portions.

15. The step of removing the ink includes: Scrape the surface of the mold with the doctor blade to align the light emitting elements; The method for manufacturing a display device according to claim 12 , further comprising: irradiating the surface of the mold with light to remove the solvent of the ink remaining on the surface of the mold.

16. The step of removing the ink includes: vibrating the mold using a vibrating device so that at least a portion of the light emitting element is filled in the recess; Scrape the surface of the mold with the doctor blade to align the light emitting elements; The method for manufacturing a display device according to claim 12 , further comprising: irradiating the surface of the mold with light to remove the solvent of the ink remaining on the surface of the mold.

17. The step of separating the mold from the substrate includes a step of applying an electric field to the substrate using an electric field application device to fix the light emitting element on the electrode; The method for manufacturing a display device according to claim 12, further comprising: a step of vertically moving the mold to separate it from the substrate.

18. The step of separating the mold from the substrate includes: The method of manufacturing a display device according to claim 17 , further comprising the step of irradiating light onto the substrate from which the mold has been separated to remove the solvent of the ink remaining on the surface of the substrate.

19. The step of separating the mold from the substrate includes: applying an electric field to the substrate using an electric field application device to fix the light emitting element on the electrode; applying vibration to the substrate with a vibration device; The method for manufacturing a display device according to claim 12, further comprising: a step of vertically moving the mold to separate it from the substrate.

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