Display module including color conversion layer formed on self luminescence element and manufacturing method as the same

Abstract

The present disclosure provides a display module and a method for manufacturing a display module. A display module according to one embodiment of the present disclosure includes a substrate and a plurality of pixels formed on the substrate. Each of the plurality of pixels comprises: a first, second, and third self-emissive element emitting light of a first wavelength band; a first color conversion layer disposed on the first self-emissive element and comprising a plurality of first quantum dots that absorb light of the first wavelength band emitted from the first self-emissive element and emit light of the second wavelength band; and a second color conversion layer disposed on the second self-emissive element and comprising a plurality of second quantum dots that absorb light of the first wavelength band emitted from the second self-emissive element and emit light of the third wavelength band. Each of the first and second color conversion layers comprises a plurality of bubble particles for scattering light emitted from the first and second self-emissive elements, respectively.

Description

Technology Field

[0001] The present disclosure relates to a display module and a method for manufacturing the same. More specifically, it relates to a display module comprising a self-luminous element and a color conversion layer formed on the self-luminous element, and a method for manufacturing the same. Background Technology

[0002] With the recent advancement of electronic technology, the use of display modules and devices that display images using quantum dots is increasing. Quantum dots absorb light emitted by self-luminous elements included in the display module and then emit light in a wavelength range different from the absorbed light. At this time, quantum dots may be included in a color conversion layer formed on the self-luminous elements; in the case of quantum dot-based displays, multiple scattering particles are included within the color conversion layer containing the quantum dots. The multiple scattering particles serve to scatter light that is emitted without being absorbed by the quantum dots. means of solving the problem

[0003] A display module according to one embodiment of the present disclosure includes a substrate and a plurality of pixels formed on the substrate. Each of the plurality of pixels includes a first, second, and third self-emissive element that emits light in a first wavelength band. Each of the plurality of pixels includes a first color conversion layer disposed on the first self-emissive element and comprising a plurality of first quantum dots that absorb light in a first wavelength band emitted from the first self-emissive element and emit light in a second wavelength band. Each of the plurality of pixels includes a second color conversion layer disposed on the second self-emissive element and comprising a plurality of second quantum dots that absorb light in a first wavelength band emitted from the second self-emissive element and emit light in a third wavelength band. Each of the first and second color conversion layers includes a plurality of bubble particles for scattering light emitted from the first and second self-emissive elements, respectively.

[0004] Here, the diameter of any one of the plurality of bubble particles is 0.74 μm to 1.26 μm.

[0005] In addition, the plurality of bubble particles are bubble particles of an inert gas.

[0006] In addition, the volume fraction of the plurality of bubble particles for each of the first and second color conversion layers is 2.5% to 9%.

[0007] In addition, each of the first and second color conversion layers further includes a plurality of scattering particles.

[0008] In addition, the mass ratio of the plurality of first quantum dots and the plurality of scattering particles included in the first color conversion layer is 1:0.04 to 1:0.14, and the mass ratio of the plurality of second quantum dots and the plurality of scattering particles included in the second color conversion layer is 1:0.04 to 1:0.14.

[0009] Meanwhile, the first, second, and third self-emissive elements are Blue Micro Light Emitting Diodes.

[0010] Here, the plurality of first quantum dots absorb light of a blue wavelength and emit light of a red wavelength, and the plurality of second quantum dots absorb light of a blue wavelength and emit light of a green wavelength.

[0011] Meanwhile, the display module of the present disclosure further includes a first color filter disposed on the first color conversion layer and a second color filter disposed on the second color conversion layer.

[0012] Herein, the display module of the present disclosure further includes a first transparent resin layer disposed on the third self-emissive element and a second transparent resin layer disposed on the plane where the first and second color filters are located, when disposed on the first color conversion layer.

[0013] A method for manufacturing a display module according to one embodiment of the present disclosure for achieving the above objectives includes the step of mounting first to third self-emissive elements corresponding to a plurality of subpixels on a first substrate. Additionally, the method for manufacturing a display module includes the step of forming first and second color conversion layers containing a plurality of bubble particles in an area corresponding to the first and second self-emissive elements among an area partitioned by a plurality of partitions formed on a second substrate, and forming a transparent resin layer in an area corresponding to the third self-emissive element among the area partitioned by the plurality of partitions. Additionally, the method for manufacturing a display module includes the step of bringing the first substrate and the second substrate into close contact to bond the plurality of color conversion layers onto the first and second self-emissive elements and bonding the transparent resin layer onto the third self-emissive element. Here, the first color conversion layer includes a plurality of first quantum dots that absorb light of a first wavelength band emitted from the first self-luminous element and emit light of a second wavelength band, and the second color conversion layer includes a plurality of second quantum dots that absorb light of the first wavelength band emitted from the second self-luminous element and emit light of a third wavelength band. Here, the light emitted from the first and second self-luminous elements, respectively, is scattered by a plurality of bubble particles included in the first and second color conversion layers.

[0014] Here, the forming step comprises forming a plurality of black matrices at predetermined intervals on a second substrate, forming a color filter between the plurality of black matrices formed on the second substrate, and forming a partition on each black matrix to divide it into regions corresponding to a plurality of subpixels.

[0015] In addition, the manufacturing method further includes the step of aligning the first substrate and the second substrate such that the first color conversion layer corresponds to the first self-luminous element, the second color conversion layer corresponds to the second self-luminous element, and the transparent resin layer corresponds to the third self-luminous element.

[0016] In addition, the diameter of any one of the plurality of bubble particles is 0.74 μm to 1.26 μm.

[0017] In addition, the plurality of bubble particles are bubble particles of an inert gas.

[0018] In addition, the volume fraction of the plurality of bubble particles for each of the first and second color conversion layers is 2.5% to 9%.

[0019] In addition, each of the first and second color conversion layers further includes a plurality of scattering particles.

[0020] Here, the size of each of the plurality of first quantum dots is larger than the size of each of the plurality of second quantum dots, and the number of scattering particles included in the first color conversion layer is greater than the number of scattering particles included in the second color conversion layer.

[0021] In addition, the mass ratio of the plurality of first quantum dots and the plurality of scattering particles included in the first color conversion layer is 1:0.04 to 1:0.14, and the mass ratio of the plurality of second quantum dots and the plurality of scattering particles included in the second color conversion layer is 1:0.04 to 1:0.14.

[0022] Meanwhile, the first, second, and third self-emissive elements are Blue Micro Light Emitting Diodes. Brief explanation of the drawing

[0023] FIG. 1 is a schematic front view showing a display module according to a first embodiment of the present disclosure. FIG. 2 is a schematic block diagram showing a display module according to a first embodiment of the present disclosure. FIG. 3 is a cross-sectional view showing a single pixel of a display module including a bubble particle-based color conversion layer according to one embodiment of the present disclosure. FIG. 4 is a cross-sectional view showing a single pixel of a display module including a color conversion layer based on bubble particles and scattering particles according to one embodiment of the present disclosure. FIG. 5 is a diagram showing the brightness retention rate of a display module including a bubble particle-based color conversion layer according to one embodiment of the present disclosure. FIG. 6 is a schematic flowchart relating to a method for manufacturing a display module according to one embodiment of the present disclosure. FIG. 7 is a flowchart showing the manufacturing process of a first part of a display module according to one embodiment of the present disclosure. FIG. 8 is a process diagram of a first part of a display module according to one embodiment of the present disclosure. FIG. 9 is an exemplary diagram illustrating a method for manufacturing a first color-changing layer comprising a plurality of bubble particles according to one embodiment of the present disclosure. FIG. 10 is a flowchart showing the manufacturing process of a second part of a display module according to one embodiment of the present disclosure. FIG. 11 is a process diagram of a second part of a display module according to one embodiment of the present disclosure. FIG. 12 is a process diagram for combining a first part and a second part of a display module according to one embodiment of the present disclosure. Specific details for implementing the invention

[0024] The terms used in this specification will be briefly explained, and the present disclosure will be described in detail.

[0025] The terms used in the embodiments of this disclosure have been selected to be as widely used as possible, taking into account their functions within this disclosure; however, these terms may vary depending on the intent of those skilled in the art, case law, the emergence of new technologies, etc. Additionally, in specific cases, terms have been arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the relevant explanatory section of this disclosure. Therefore, terms used in this disclosure should be defined not merely by their names, but based on their meanings and the overall content of this disclosure.

[0026] In this specification, expressions such as “have,” “may have,” “include,” or “may include” indicate the presence of such features (e.g., numerical values, functions, operations, or components such as parts) and do not exclude the presence of additional features.

[0027] The expression "at least one of A or / and B" should be understood as representing either "A" or "B" or "A and B".

[0028] Expressions such as "first," "second," "first," or "second" used in this specification may modify various components regardless of order and / or importance, and are used only to distinguish one component from another and do not limit said components.

[0029] Where it is stated that a component (e.g., Component 1) is "(operatively or communicatively) coupled with / to" or "connected to" another component (e.g., Component 2), it should be understood that the component may be directly connected to the other component or connected through the other component (e.g., Component 3).

[0030] The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "consisting of" are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0031] In the present disclosure, a "module" or "part" performs at least one function or operation and may be implemented in hardware or software, or a combination of hardware and software. Additionally, a plurality of "modules" or a plurality of "parts" may be integrated into at least one module and implemented by at least one processor (not shown), except for a "module" or "part" that needs to be implemented in specific hardware.

[0032] In the present disclosure, the display module may be a display panel equipped with a micro light-emitting diode (hereinafter referred to as micro LED), which is a self-luminescence element for displaying images. The display module is one of flat panel display panels and is composed of a plurality of inorganic light-emitting diodes, each measuring 100 micrometers or less, providing better contrast, response time, and energy efficiency compared to a liquid crystal display (hereinafter referred to as LCD) panel that requires a backlight. Since the micro light-emitting diode used for displaying images is a self-luminescence element, the display module does not require a separate backlight.

[0033] In the present disclosure, micro LEDs, which are inorganic light-emitting devices, have longer brightness, luminous efficiency, and lifespan than organic light-emitting diodes (Organic LEDs, hereinafter referred to as OLEDs). Micro LEDs may be semiconductor chips capable of emitting light on their own when power is supplied. Micro LEDs have a fast response speed, low power consumption, and high brightness. For example, micro LEDs have a higher efficiency in converting electricity into photons compared to conventional LCDs or OLEDs. That is, they have a higher "brightness per watt" compared to conventional LCD or OLED displays. Accordingly, micro LEDs can produce the same brightness with about half the energy compared to conventional LEDs (where the width, height, and depth each exceed 100 μm) or OLEDs. In addition, micro LEDs enable high resolution, excellent color, contrast, and brightness, allowing for accurate representation of a wide range of colors and the creation of a clear screen even outdoors. Furthermore, micro LEDs are resistant to burn-in and generate little heat, ensuring a long lifespan without deformation. Micro LEDs may have a flip chip structure in which an anode and a cathode electrode are formed on the same first surface and a light-emitting surface is formed on a second surface located on the opposite side of the first surface where the electrodes are formed.

[0034] In the present disclosure, one pixel may include at least three subpixels. One subpixel may be a self-luminescence element for image display, such as a micro LED, a blue micro light emitting diode, or an ultraviolet micro light emitting diode. Here, the blue micro LED may be a self-luminescence element that emits light in the blue wavelength band (450 to 490 nm), and the UV micro LED may be a self-luminescence element that emits light in the ultraviolet wavelength band (360 to 410 nm).

[0035] In the present disclosure, one subpixel may include one micro self-luminescent element, along with a corresponding color conversion layer and a color filter. The color conversion layer may be excited by light emitted from the micro self-luminescent element to emit a color of a predetermined wavelength band. The color conversion layer may be made of a material including a nanophosphor or a quantum dot.

[0036] In the present disclosure, a subpixel region refers to a region in which the color of a corresponding subpixel is expressed by light emitted from a subpixel. In the present disclosure, the area (horizontal length × vertical length) of one side of the color conversion layer corresponding to the subpixel may be larger than the area of ​​the light-emitting surface of the subpixel. In this case, the subpixel region may correspond to the area of ​​the color conversion layer.

[0037] In the present disclosure, a substrate may have a TFT layer having a Thin Film Transistor (TFT) circuit formed thereon disposed on its front surface, and on its rear surface disposed a power supply circuit for supplying power to the TFT circuit, a data driving driver, a gate driving driver, and a timing controller for controlling each driving driver. A plurality of pixels arranged on the TFT layer may be driven by the TFT circuit.

[0038] In the present disclosure, the substrate may be a glass substrate, a synthetic resin-based substrate (e.g., PI (Polyimide), PET (Polyethylene Terephthalate), PES (Polyethersulfone), PEN (Polyethylene Naphthalate), PC (Polycarbonate), etc.), or a ceramic substrate.

[0039] In the present disclosure, a TFT layer having a TFT circuit formed thereon is disposed on the front surface of a substrate, and no circuit may be disposed on the back surface of the substrate. The TFT layer may be formed integrally on the substrate or manufactured in the form of a separate film and attached to one side of a glass substrate.

[0040] In the present disclosure, the front surface of a substrate may be divided into an active region and an inactive region. The active region may correspond to the area occupied by the TFT layer on the front surface of the substrate, and the inactive region may be the area excluding the area occupied by the TFT layer on the front surface of the substrate.

[0041] In the present disclosure, the edge region of the substrate may be the outermost region of the glass substrate. Additionally, the edge region of the substrate may be the remaining region excluding the region where the circuit of the substrate is formed. Additionally, the edge region of the substrate may include a portion of the front surface of the substrate adjacent to the side surface of the substrate and a portion of the rear surface of the substrate adjacent to the side surface of the substrate. The substrate may be formed in a quadrangle type. Specifically, the substrate may be formed in a rectangle or a square. The edge region of the substrate may include at least one of the four sides of the glass substrate.

[0042] In the present disclosure, the TFT constituting the TFT layer (or backplane) is not limited to a specific structure or type. For example, the TFT cited in the present disclosure may be implemented as an oxide TFT and Si TFT (poly silicon, a-silicon), organic TFT, graphene TFT, etc., in addition to an LTPS TFT (Low-temperature polycrystalline silicon TFT), and may also be applied by manufacturing only a P-type (or N-type) MOSFET in a Si wafer CMOS process.

[0043] In the present disclosure, the pixel driving method of the display module may be an Active Matrix (AM) driving method or a Passive Matrix (PM) driving method. The display module may form a wiring pattern in which each micro LED is electrically connected according to the AM driving method or the PM driving method.

[0044] In the present disclosure, a plurality of Pulse Amplitude Modulation (PAM) control circuits may be disposed in a single pixel area. In this case, each subpixel disposed in a single pixel area may be controlled by a corresponding PAM control circuit. Additionally, a plurality of Pulse Width Modulation (PWM) control circuits may be disposed in a single pixel area. In this case, each subpixel disposed in a single pixel area may be controlled by a corresponding PWM control circuit.

[0045] In the present disclosure, a plurality of PAM control circuits and a plurality of PWM control circuits may be disposed together in a single pixel area. In this case, some of the subpixels disposed in a single pixel area may be controlled by the PAM control circuit, and the remainder may be controlled through the PWM control circuit. Additionally, each subpixel may be controlled by the PAM control circuit and the PWM control circuit.

[0046] In the present disclosure, the display module may include a plurality of side wirings of thin film thickness arranged at regular intervals along the side of a TFT substrate.

[0047] In the present disclosure, the display module may provide a plurality of through-wire members formed so as not to be exposed to the side of the TFT substrate, instead of side wiring exposed to the side of the TFT substrate. Accordingly, by minimizing the inactive area and maximizing the active area on the front surface of the TFT substrate, it is possible to achieve a bezel-less design and increase the mounting density of the micro LEDs in the display module.

[0048] In the present disclosure, a display module that implements bezel-less design can provide a large-sized multi-display device capable of maximizing the active area when multiple modules are connected. In this case, each display module can be formed such that the pitch between each pixel of adjacent display modules is maintained to be the same as the pitch between each pixel within a single display module, thereby minimizing the inactive area. Accordingly, this may be one method to ensure that the seam is not visible at the connection portion between each display module.

[0049] In the present disclosure, the driving circuit may be implemented by a micro IC disposed in a pixel area to control driving at least 2n pixels. When a micro IC is applied to a display module, only a channel layer connecting the micro IC and each micro LED may be formed in the TFT layer (or backplane) instead of a TFT.

[0050] In the present disclosure, the display module can be installed and applied as a single unit in electronic products or battlefields requiring various displays, such as wearable devices, portable devices, handheld devices, and various displays, and can be applied to display devices such as PC (personal computer) monitors, high-resolution TVs, signage (or digital signage), and electronic displays through a plurality of assembled arrangements in a matrix type.

[0051] The present disclosure will be described in detail below with reference to the attached drawings.

[0052] FIG. 1 is a schematic front view showing a display module according to a first embodiment of the present disclosure, and FIG. 2 is a schematic block diagram showing a display module according to a first embodiment of the present disclosure.

[0053] Referring to FIG. 1 and FIG. 2, a display module (10) according to the present disclosure may include a TFT substrate (20) having a plurality of pixel driving circuits (30) formed thereon, a plurality of pixels (100) arranged on the front surface of the TFT substrate (20), and a panel driving unit (40) that generates a control signal and provides the generated control signal to the plurality of pixel driving circuits (30).

[0054] In the present disclosure, a single pixel may include a plurality of subpixels. A single subpixel may include a single self-light emitting element and a color conversion layer and a color filter corresponding to each self-light emitting element. Here, the self-light emitting element may be an inorganic self-light emitting diode, for example, a VCSEL diode (Vertical Cavity Surface Emitting Laser diode) or a micro LED (Micro light emitting diode) having a size of 100 μm or less (preferably 30 μm or less). The VCSEL diode and the micro LED may emit light in the blue wavelength band (450–490 nm) or light in the ultraviolet wavelength band (360–410 nm). The structure of the pixel (100) is described in detail below with reference to FIG. 3.

[0055] The TFT substrate (20) may include a glass substrate (21), a TFT layer (23) having a TFT (Thin Film Transistor) circuit on the front surface of the glass substrate (21), and a plurality of side wirings (25) that electrically connect the TFT circuit of the TFT layer (23) and circuits (not shown) arranged on the back surface of the glass substrate.

[0056] In the present disclosure, as an alternative to the glass substrate (21), a substrate of a synthetic resin series having a flexible material (e.g., PI (Polyimide), PET (Polyethylene Terephthalate), PES (Polyethersulfone), PEN (Polyethylene Naphthalate), PC (Polycarbonate), etc.) or a ceramic substrate may be used.

[0057] The TFT substrate (20) may include an active area (20a) that displays an image on the front surface and a dummy area (20b) that cannot display an image.

[0058] The active area (20a) may be divided into multiple pixel areas (24) in which multiple pixels are arranged. The multiple pixel areas (24) may be divided in various forms, and as an example, may be divided in a matrix form. One pixel area (24) may contain one pixel (100, see FIG. 3).

[0059] The inactive area (20b) may be included in the edge area of ​​the glass substrate, and a plurality of connection pads (28a) may be formed at regular intervals along the edge area. Each of the plurality of connection pads (28a) may be electrically connected to each pixel driving circuit (30) through wiring (28b).

[0060] The number of connection pads (28a) formed in the inactive area (20b) may vary depending on the number of pixels implemented on the glass substrate and the driving method of the TFT circuit placed in the active area (20a). For example, compared to the case where the TFT circuit placed in the active area (20a) is a PM (Passive Matrix) driving method that drives multiple pixels in horizontal and vertical lines, an AM (Active Matrix) driving method that drives each pixel individually may require more wiring and connection pads.

[0061] The TFT layer (23) may include a plurality of data signal lines arranged horizontally to control a plurality of pixels (100), a plurality of gate signal lines arranged vertically, and a plurality of pixel driving circuits (30) electrically connected to each line.

[0062] The panel driver (40) may be directly connected to the substrate via a COG (Chip on Class) or COP (Chip on Plastic) bonding method, or indirectly connected to the TFT substrate (20) via a separate FPCB via a FOG (Film on Glass) bonding method. The panel driver (40) can drive a plurality of pixel driving circuits (30) to control the light emission of a plurality of micro LEDs electrically connected to each of the plurality of pixel driving circuits (30).

[0063] The panel driving unit (40) can control a plurality of pixel driving circuits (30) line by line through the first driving unit (41) and the second driving unit (42). The first driving unit (41) can generate a control signal to sequentially control a plurality of horizontal lines formed on the TFT substrate (20) one line per image frame and transmit the generated control signal to the pixel driving circuits (30) each connected to the corresponding lines. The second driving unit (42) can generate a control signal to sequentially control a plurality of vertical lines formed on the TFT substrate (20) one line per image frame and transmit the generated control signal to the pixel driving circuits (30) each connected to the corresponding lines.

[0064] FIG. 3 is a cross-sectional view showing a single pixel of a display module including a bubble particle-based color conversion layer according to one embodiment of the present disclosure.

[0065] Referring to FIG. 3, one pixel (100) can be included in one pixel area (24, see FIG. 1).

[0066] According to one embodiment of the present disclosure, each of the plurality of pixels (100) includes a plurality of self-luminous elements that emit light of the same color. Specifically, the plurality of pixels (100) include first, second, and third self-luminous elements that emit light of a first wavelength band.

[0067] In one embodiment of the present disclosure, the first, second, and third self-emissive elements may each be a micro LED (first, second, and third micro LED) that emits light in a blue wavelength band (450 to 490 nm). In this case, each micro LED may correspond to each sub-pixel included in the pixel (100). For example, the first sub-pixel of the pixel (100) may correspond to the first micro LED, the second sub-pixel may correspond to the second micro LED, and the third sub-pixel may correspond to the third micro LED. Hereinafter, the first, second, and third self-emissive elements according to the present disclosure will be described by assuming they are micro LEDs that emit light in a blue wavelength band. Accordingly, the first self-emissive element will be referred to as the first micro LED, the second self-emissive element as the second micro LED, and the third self-emissive element as the third micro LED.

[0068] The first and second micro LEDs (61, 62) may be vertical cavity surface emitting laser (VCSEL) diodes so that light is not emitted to the back (the side where the chip electrode is located) and side of the first and second micro LEDs (61, 62) but is emitted only to the light-emitting surface in a direction perpendicular to the surface of the TFT substrate (20).

[0069] The first to third micro LEDs (61, 62, 63) can be electrically and physically connected to the TFT substrate (20) through an anisotropic conductive film (ACF) (50) laminated to the front surface of the TFT substrate (20).

[0070] Meanwhile, an anisotropic conductive film may be formed on the TFT substrate (20). At this time, the anisotropic conductive film (50) comprises a thermosetting resin (epoxy resin, polyurethane resin, acrylic resin, etc.) and a plurality of conductive balls having a fine diameter (e.g., 3 to 15 μm) within the thermosetting resin. Each conductive ball may comprise a polymer particle and a conductive film such as Au, Ni, or Pd coated on the surface of the polymer particle. The anisotropic conductive film (50) has conductivity in the compression direction and insulation in the direction perpendicular to the compression direction.

[0071] The first to third micro LEDs (61, 62, 63) may have a flip-chip structure in which two chip electrodes (61a, 61b), which are anode and cathode electrodes, are formed on opposite sides of the light-emitting surface. The first and second chip electrodes (61a, 61b) may be made of any one of Al, Ti, Cr, Ni, Pd, Ag, Ge, Au, or an alloy thereof.

[0072] When the first to third micro LEDs (61, 62, 63) are transferred to the TFT substrate (20), they are placed on the surface of the anisotropic conductive film (50) attached to the TFT substrate (20). Subsequently, through a thermal compression process, the first to third micro LEDs (61, 62, 63) are inserted together into the anisotropic conductive film (50) to a predetermined depth. Accordingly, the first to third micro LEDs (61, 62, 63) can be physically fixed to the TFT substrate (20) by the anisotropic conductive film (50).

[0073] Additionally, as the first micro LED (61) is pressed toward the TFT substrate (20) by a thermal compression process, the chip electrodes (61a, 61b) of the first micro LED (61) may be positioned adjacent to the electrode pads of the TFT substrate (20). In this case, the chip electrodes (61a, 61b) of the first micro LED (61) may be electrically connected to the substrate electrode pads by a conductive ball located between the chip electrodes (61a, 61b) of the first micro LED (61) and the substrate electrode pads. Likewise, the second and third micro LEDs (62, 63) may also be electrically connected to the substrate electrode pads corresponding to each chip electrode via conductive balls in the same manner as the first micro LED (61).

[0074] Meanwhile, a first color conversion layer is disposed on the first self-luminous element. At this time, the first color conversion layer includes a plurality of first quantum dots that absorb light of a first wavelength band emitted from the first self-luminous element and emit light of a second wavelength band. Then, a second color conversion layer is disposed on the second self-luminous element. At this time, the second color conversion layer includes a plurality of second quantum dots that absorb light of a first wavelength band emitted from the second self-luminous element and emit light of a third wavelength band.

[0075] Specifically, the first color conversion layer (71) includes a first quantum dot (71b) that absorbs light of a first wavelength band emitted from a first micro LED (61) and emits light of a second wavelength band. Additionally, the second color conversion layer (72) includes a second quantum dot (72b) that absorbs light of a third wavelength band emitted from a second micro LED (62) and emits light of a second wavelength band.

[0076] According to one embodiment of the present disclosure, the first color conversion layer (71) may be made of a material comprising a red quantum dot (71a) (Quantum Dot) that emits light in the red wavelength band and emits light in the blue band emitted from a blue micro LED (61). And the second color conversion layer (72) may be made of a material comprising a green quantum dot that absorbs light in the blue wavelength band emitted from a blue micro LED and emits light in the green wavelength band.

[0077] Here, quantum dots can be small spherical semiconductor particles of nanometer (nm, 1 / 1,000,000,000 meter) size, and can have a size of approximately 2 nm to 10 nm. Quantum dots can be composed of a core made of cadmium selenite (CdSe), cadmium telluride (CdTe), or cadmium sulfide (CdS), and a surface made of zinc sulfide (ZnS).

[0078] The energy band gap between the valence band and the conduction band of a quantum dot varies depending on its size. Specifically, when the size of the quantum dot becomes smaller than the Bohr radius (for example, when the size of the quantum dot becomes 10 nm), the energy band gap increases due to the quantum confinement effect. As the energy band gap increases, the quantum dot emits light of a shorter wavelength. In other words, the wavelength of light emitted from the quantum dot can vary depending on its size. Therefore, the diameter of the red quantum dot (71a) included in the first color conversion layer (71) may be approximately 7 nm, and the diameter of the green quantum dot (72a) included in the second color conversion layer (72) may be approximately 4 nm.

[0079] For convenience of explanation of the present disclosure, the light in the second wavelength band is assumed to be red light and the light in the third wavelength band is assumed to be green light.

[0080] Meanwhile, the first and second color conversion layers (71, 72) may include nano phosphors that absorb light emitted from the first and second micro LEDs (61, 62) as an alternative to the first and second quantum dots, convert it into light of different wavelength bands, and emit it. Nano phosphors exhibit different physical properties compared to conventional phosphors with particle diameters of several μm. For example, the energy band gap, which is the quantum state energy level structure of electrons within the crystal of the nano phosphor, is large, so the wavelength of the emitted light has high energy, thereby improving luminescence efficiency. Compared to phosphors with a bulk structure, the nano phosphor has an increased particle density, allowing striking electrons to effectively contribute to light emission, thereby improving the efficiency of the display.

[0081] The first color conversion layer (71) may include a red nanophosphor capable of emitting light in the red wavelength band when excited by light in the blue wavelength band emitted from the first micro LED (61). For example, the red nanophosphor is SCASN (Si 1-x Ca x AlSiN3:Eu 2+ ) It can be. In this case, the red nanophosphor is the average value of the particle size distribution (d 50 ) is less than 0.5㎛ (preferably 0.1㎛ < d 50 It can be < 0.5㎛).

[0082] The second color conversion layer (72) may include a green nanophosphor capable of emitting light in a green wavelength band when excited by light in a blue wavelength band emitted from the second micro LED (62). For example, the green nanophosphor is β-SiAlON (Si 6-z Al z O z N 8-z :Eu 2+ It can be ) or SrGa2S4. In this case, the green nanophosphor is the average value of the particle size distribution (d50 ) is less than 0.5㎛ (preferably 0.1㎛ < d 50 It can be < 0.5㎛).

[0083] For convenience of explaining the present disclosure, the first and second color conversion layers (71, 72) are described as each including a plurality of red quantum dots and a plurality of green quantum dots.

[0084] The first transparent resin layer (73) may be made of a material that does not affect or minimizes the transmittance, reflectance, and refractive index of light emitted from the third micro LED (63). The first transparent resin layer (73) may be composed of various transparent resins such as PC (Polycarbonate), PES (Polyether Sulfone), PMMA (Polymethyl Methacrylate), PVA (Polyvinyl alcohol), and PI (Polyimide). Meanwhile, the first transparent resin layer (73) may be omitted depending on the case, in which case an air layer is present on the light-emitting surface side of the third micro LED (63).

[0085] Each of the first and second color conversion layers (71, 72) includes a plurality of bubble particles (71b, 72b) for scattering light emitted from the first and second micro LEDs (61, 62), respectively. The plurality of bubble particles (71b, 72b) are distributed within the first and second color conversion layers (71, 72) to uniformly disperse the light emitted from the first and second micro LEDs (61, 62) throughout the first and second color conversion layers (71, 72). Specifically, so that light emitted from the first and second micro LEDs (61, 62) is not absorbed and emitted by the quantum dots included in the first and second color conversion layers (71, 72) respectively (i.e., a plurality of red quantum dots (71a) included in the first color conversion layer (71) and a plurality of green quantum dots (72a) included in the second color conversion layer (72)), a plurality of bubble particles (71b, 72b) scatter the light emitted from the first and second micro LEDs (61, 62) respectively. Accordingly, the luminance dispersion within the sub-pixel area can be reduced and partial degradation at the point where light is concentrated within the sub-pixel area can be prevented.

[0086] Multiple bubble particles (71b, 72b) can be distributed according to a preset pattern and can scatter light emitted from the first and second micro LEDs within a certain range.

[0087] The diameter of a plurality of bubble particles (71b, 72b) included in the first and second color conversion layers (71, 72) according to one embodiment of the present disclosure may be 0.74 μm to 1.26 μm.

[0088] In addition, the plurality of bubble particles (71b, 72b) according to one embodiment of the present disclosure may be bubble particles of an inert gas. As an example, the plurality of bubble particles (71b, 72b) may be bubble particles of an inert gas such as Ar or N2.

[0089] Additionally, the volume fraction of the plurality of bubble particles (71b, 72b) for each of the first and second color conversion layers (71, 72) may be 2.5% to 9%. Here, the volume fraction may be the ratio of the total volume occupied by the plurality of bubble particles to the volume of each color conversion layer (71, 72). The volume fraction of the plurality of bubble particles (71b, 72b) may be determined based on the total volume of each color conversion layer (first color conversion layer (71) and second color conversion layer (72)), the size and number of the plurality of bubble particles (71b, 72b) included in each color conversion layer (first color conversion layer (71) and second color conversion layer (72)).

[0090] Meanwhile, according to an embodiment of the present disclosure, the volume fraction of a plurality of bubble particles (71b, 72b) included in each color conversion layer (71, 72) may be set differently depending on the wavelength of light emitted from each color conversion layer (71, 72). Specifically, the volume fraction of a plurality of bubble particles (71b, 72b) included in the first color conversion layer (71) and the volume fraction of a plurality of bubble particles (71b, 72b) included in the second color conversion layer may be different from each other.

[0091] Specifically, the volume fraction of a plurality of bubble particles (71b, 72b) included in each of the first and second color conversion layers (71, 72) may be determined differently based on the size of the quantum dots included in the first and second color conversion layers (71, 72). For example, the volume fraction of a plurality of bubble particles (71b) in the first color conversion layer (71) containing red quantum dots (71a) having a relatively large size may be smaller than the volume fraction of a plurality of bubble particles (72b) in the second color conversion layer (72) containing green quantum dots (72a) having a relatively small size. That is, the volume fraction of a plurality of bubble particles (71b, 72b) for each of the first and second color conversion layers (71, 72) may be set differently based on the wavelength of light emitted from each color conversion layer (i.e., the first and second color conversion layers (71, 72)).

[0092] The first color conversion layer (71) may be composed of a photocurable resin material. That is, the first color conversion layer (71) may be formed on the first micro LED (61) by applying a photocurable resin material containing a plurality of red quantum dots (71a) and a plurality of bubble particles (71b) onto the first micro LED (61) and then curing it. The second color conversion layer may also be composed of a photocurable resin material and may be formed on the second micro LED (62) in the same way as the first color conversion layer (71). Meanwhile, as an example, the photocurable resins of the first and second color conversion layers (71 and 72) may be epoxy, acrylate, methacrylate, urethane, or silane resins.

[0093] Additionally, the pixel (100) may include first and second color filters (81, 82) corresponding to the first and second color conversion layers (71, 72), respectively, and may include a second transparent resin layer (83) corresponding to the first transparent resin layer (73).

[0094] The first color filter (81) may be a red color filter that passes a wavelength of the same color as the light in the red wavelength band emitted from the first color conversion layer (71). The second color filter (82) may be a green color filter that passes a wavelength of the same color as the light in the green wavelength band emitted from the second color conversion layer (72).

[0095] The second transparent resin layer (83) may be made of a material that does not affect or minimizes the transmittance, reflectance, and refractive index of light passing through the first transparent resin layer (73). Additionally, the second transparent resin layer (83) may be an optical film that can minimize wasted light and improve brightness by directing the direction of light toward the front through refraction and reflection.

[0096] The first to third micro LEDs (61, 62, 63) may have a predetermined thickness and be squares with equal width and length, or rectangles with different widths and lengths. Such micro LEDs can enable Real HDR (High Dynamic Range) implementation and provide improved brightness and black expression capabilities compared to OLEDs, as well as a high contrast ratio. The size of the micro LEDs may be 100㎛ or less, or preferably 30㎛ or less.

[0097] Referring again to FIG. 3, the pixel (100) may have the light-emitting regions of the first to third micro LEDs (61, 62, 63) partitioned by a partition (70). The partition (70) may be formed in a roughly grid shape. Each of the light-emitting regions partitioned by the partition (70) may correspond to one sub-pixel region.

[0098] The partition wall (70) can have its upper end in contact with the black matrix (74) and its lower end in contact with the upper surface of the anisotropic conductive film (50). In each light-emitting area partitioned by the partition wall (70), a first color conversion layer (71), a second color conversion layer (72), and a first transparent resin layer (73) can be disposed.

[0099] Accordingly, light emitted from the side of the first color conversion layer (71) corresponding to the first micro LED (61) can be reflected by the partition wall (70) and emitted to the first color filter (81). Additionally, light emitted from the side of the second color conversion layer (72) corresponding to the second micro LED (62) can be reflected by the partition wall (70) and emitted to the second color filter (82).

[0100] The partition (70) may have a white color with excellent light reflectivity to function as a reflector. Here, the white color may include true white and off-white. Off-white refers to any color close to white.

[0101] The partition wall (70) may be formed of a metal material having a high reflectivity so that it can function as a reflector. Additionally, a metal film having a high light reflectivity may be laminated and formed on the side of the partition wall (70).

[0102] The light-emitting surfaces of the first to third micro LEDs (61, 62, 63) may be located at approximately the same height from the upper surface of the TFT substrate (20). Additionally, the light-emitting surfaces of the first to third micro LEDs (61, 62, 63) may be located at a position higher than the bottom of the partition wall (70). In this case, a portion of the side of the first to third micro LEDs (61, 62, 63) may face the partition wall (70). Accordingly, light emitted from the side of the first to third micro LEDs (61, 62, 63) may be reflected by the partition wall (70) and emitted to the first and second color conversion layers (71, 72) and the first transparent resin layer (73).

[0103] In this way, the partition wall (70) can maximize light emission efficiency by reflecting the light emitted from the sides of the first to third micro LEDs (61, 62, 63), the light emitted from the sides of the first and second color conversion layers (71, 72), and the light emitted from the side of the first transparent resin layer (73), respectively, and emitting them to the front of the display module (10).

[0104] Meanwhile, although not clearly illustrated in the drawing, a flattening layer may be disposed between the first and second color conversion layers (71, 72) and the first and second color filters (81, 82). Additionally, a flattening layer may also be disposed between the first transparent resin layer (73) and the second transparent resin layer (83).

[0105] The flattening layer may be made of a material that does not affect or minimizes the transmittance, reflectance, and refractive index of light passing through the first and second color conversion layers (71, 72) and the first transparent resin layer (73).

[0106] The first and second color filters (81, 82) and the second transparent resin layer (83) may be separated by a black matrix (74) formed in a grid shape. The shape of the black matrix (74) may be formed in a grid shape to correspond to the shape of the partition wall (70). In this case, the width of the black matrix (74) may be formed to be similar to the width of the partition wall (70).

[0107] A transparent cover layer (90) may be formed on the upper side of the first and second color filters (81, 82) and the second transparent resin layer (83). The transparent cover layer (90) can prevent the pixel (100) from being contaminated by foreign substances and protect the pixel (100) from being damaged by external forces. A glass substrate may be used for the transparent cover layer (90).

[0108] In FIG. 3, only the portions of the partition wall (70), black matrix (74), and transparent cover layer (90) corresponding to a single pixel unit are shown, but the partition wall (70), black matrix (74), and transparent cover layer (90) can be formed with a size approximately corresponding to the size of the TFT substrate (20).

[0109] Meanwhile, the sizes of the first to third micro LEDs (61, 62, 63) are formed to be smaller than the sizes of the first and second color conversion layers (71, 72) and the first transparent resin layer (73), respectively. Accordingly, a gap may be formed between the side of the first to third micro LEDs (61, 62, 63) and the partition wall (70).

[0110] FIG. 4 is a cross-sectional view showing a single pixel of a display module including a color conversion layer based on bubble particles and scattering particles according to one embodiment of the present disclosure. In describing the display module illustrated in FIG. 4, the same reference numerals are assigned to components identical to the display module (10) described above based on FIG. 3, and descriptions are omitted.

[0111] Referring to FIG. 4, the first and second color conversion layers (71, 72) may further include a plurality of scattering particles. Specifically, the plurality of light scattering particles (71c, 72c) included in the first and second color conversion layers (71, 72), respectively, are TiO2, SiO2 2, It may be composed of ZrO or glass beads, etc. A plurality of light scattering particles are distributed within the first and second color conversion layers (71, 72) and together with a plurality of bubble particles (71b, 72b), can uniformly disperse the light emitted from the first and second micro LEDs (61, 62) throughout the first and second color conversion layers (71, 72).

[0112] Hereinafter, a plurality of scattering particles included in the first color conversion layer (71) are referred to as the first scattering particles (71c), and a plurality of scattering particles (72c) included in the second color conversion layer (72) are referred to as the second scattering particles.

[0113] According to one embodiment of the present disclosure, the mass ratio of a plurality of red quantum dots (71a) and a plurality of scattering particles included in the first color conversion layer (71) may be 1:0.04 to 1:0.14. Specifically, the total mass ratio of a plurality of red quantum dots (71a) included in the first color conversion layer (71) and the total mass ratio of a plurality of scattering particles included in the first color conversion layer (71) may be 1:0.04 to 1:0.14.

[0114] Likewise, the mass ratio of the plurality of green quantum dots (72a) and the plurality of scattering particles included in the second color conversion layer (72) may be 1:0.04 to 1:0.14. That is, the total mass ratio of the plurality of green quantum dots (72a) included in the second color conversion layer (72) and the total mass ratio of the plurality of scattering particles included in the second color conversion layer (72) may be 1:0.04 to 1:0.14.

[0115] Meanwhile, according to one embodiment of the present disclosure, the mass ratio of a plurality of quantum dots (first and second quantum dots (71a, 72a)) and a plurality of scattering particles (71c, 72c) included in each color conversion layer (first and second color conversion layers (71, 72)) may be set differently depending on the wavelength of light emitted from the quantum dots. Specifically, the mass ratio of a plurality of red quantum dots (71a) and a plurality of first scattering particles included in the first color conversion layer (71) may be different from the mass ratio of a plurality of green quantum dots (72a) and a plurality of second scattering particles included in the second color conversion layer (72). This is because the number of a plurality of scattering particles (first and second scattering particles (71c, 72c)) included in each color conversion layer (first and second color conversion layers (71, 72)) is different from the number of quantum dots (first and second) included in each color conversion layer (first and second color conversion layers (71, 72)). This is because it can be determined based on the size, number, etc. of quantum dots (71a, 72a).

[0116] FIG. 5 is a diagram showing the brightness retention rate of a display module including a bubble particle-based color conversion layer according to one embodiment of the present disclosure.

[0117] Referring to FIG. 5, compared to a conventional display module that scatters light transmitted into a color conversion layer using only conventional scattering particles, the display module of the present disclosure, which scatters light transmitted into a color conversion layer using multiple bubble particles (71b, 72b), maintains a brightness retention rate of 90% or more for a longer period of time. This is because, in the case of a conventional display module that scatters light transmitted into a color conversion layer using only conventional scattering particles, the mass ratio of multiple quantum dots and multiple scattering particles in the color conversion layer was 1:0.22. At this time, in the conventional display module, a loss of blue light occurred as the multiple scattering particles absorbed blue light emitted from the light-emitting element. Furthermore, as radicals were generated from the scattering particles that absorbed blue light, the surface of the quantum dots was damaged by the generated radicals. As a result, the light conversion efficiency of the multiple quantum dots in the color conversion layer also decreased over time. However, the display module of the present disclosure includes a plurality of bubble particles in the color conversion layer and a smaller amount of a plurality of scattering particles than conventional display modules, thereby reducing the blue light loss rate caused by the plurality of scattering particles and reducing surface damage to quantum dots caused by radicals, so that brightness can be maintained for a longer period of time.

[0118] FIG. 6 is a schematic flowchart relating to a method for manufacturing a display module according to one embodiment of the present disclosure.

[0119] Referring to FIG. 6, first, first to third self-emissive elements corresponding to a plurality of subpixels are mounted on a substrate (S610).

[0120] The first substrate may be implemented as a TFT substrate (20) having a plurality of pixel driving circuits (30) formed thereon. The first to third self-emissive elements may be micro LEDs (61, 62, 63) that emit light in a blue wavelength band (450 to 490 nm). Meanwhile, each micro LED (61, 62, 63) may correspond to each sub-pixel included in the pixel (100). For example, the first sub-pixel of the pixel (100) may correspond to the first micro LED, the second sub-pixel may correspond to the second micro LED, and the third sub-pixel may correspond to the third micro LED.

[0121] Then, a first and second color conversion layer (71, 72) containing a plurality of bubble particles (71b, 72b) is formed in an area corresponding to the first and second self-luminous elements among the areas partitioned by a plurality of partitions formed on the second substrate, and a transparent resin layer is formed in an area corresponding to the third self-luminous element among the areas partitioned by a plurality of partitions (S620).

[0122] The second substrate may be a transparent cover layer (90) as illustrated in FIG. 3. For example, the second substrate may be implemented as a glass substrate. A first color conversion layer (71) may be formed in a region corresponding to the first micro LED (61) among a plurality of regions partitioned by a plurality of partitions formed on the glass substrate, and a second color conversion layer (72) may be formed in a region corresponding to the second micro LED (62) among the plurality of regions.

[0123] At this time, the first color conversion layer (71) may be made of a material containing red quantum dots (71a) that absorb light in the blue wavelength band and emit light in the red wavelength band. And, the second color conversion layer (72) may be made of a material containing green quantum dots (72a) that absorb light in the blue wavelength band and emit light in the green wavelength band.

[0124] Meanwhile, each of the first and second color conversion layers (71, 72) may include a plurality of bubble particles (71b, 72b) for scattering light in the blue wavelength band emitted from the first and second micro LEDs (61, 62), respectively. As a result, light in the blue wavelength band emitted from the first and second self-emissive elements, respectively, may be scattered by the plurality of bubble particles (71b, 72b) included in the first and second color conversion layers (71, 72).

[0125] The first color conversion layer (71) may be composed of a photocurable resin material. A photocurable resin material containing a plurality of red quantum dots (71a) and a plurality of bubble particles (71b) may be applied to a region corresponding to the first micro LED (61) among a plurality of regions partitioned by a plurality of partitions, and the applied curable material may be cured by irradiating light. At this time, as the applied curable material is cured, the first color conversion layer (71) may be formed on the first micro LED (61). The second color conversion layer may also be composed of a photocurable resin material and may be formed on the second micro LED (62) in the same way as the first color conversion layer (71).

[0126] At this time, according to one embodiment of the present disclosure, the first and second color conversion layers (71, 72) may further include a plurality of scattering particles. That is, the first color conversion layer (71) may further include a plurality of first scattering particles that scatter light in the blue wavelength band emitted from the first micro LED (61), and the second color conversion layer (72) may further include a plurality of second scattering particles that scatter light in the blue wavelength band emitted from the second micro LED (62).

[0127] At this time, according to one embodiment of the present disclosure, the mass ratio of a plurality of first quantum dots (71a) and a plurality of scattering particles (71c) included in the first color conversion layer (71) may be 1:0.04 to 1:0.14, and the mass ratio of a plurality of second quantum dots (72a) and a plurality of scattering particles (72c) included in the second color conversion layer (72) may be 1:0.04 to 1:0.14.

[0128] Meanwhile, after forming the first and second color conversion layers (71, 72) and the transparent resin layer (73) (S620), the first substrate and the second substrate are brought into close contact to bond a plurality of color conversion layers (first and second color conversion layers (71, 72)) onto the first and second self-luminous elements (61, 62), and bond a transparent resin layer (73) onto the third self-luminous element (S630). At this time, the second substrate can be pressed toward the first substrate to bond a plurality of color conversion layers onto the first and second self-luminous elements and bond a transparent resin layer onto the third self-luminous element.

[0129] FIG. 7 is a flowchart showing the manufacturing process of a first part of a display module according to one embodiment of the present disclosure, and FIG. 8 is a process diagram of a first part of a display module according to one embodiment of the present disclosure. In FIG. 8, the entire first part of the first display module (10) is not shown, but a part corresponding to one pixel is shown in an enlarged view.

[0130] Referring to FIGS. 7 and 8, a first part of a display module (10) can be manufactured in the following order. Here, the first part may be a part that constitutes the upper surface or top plate of a display module, comprising a black matrix disposed on a second substrate of the display module (10), first and second color conversion layers (71, 72), first and second transparent resin layers, first to third color filters, and a partition wall.

[0131] First, a black matrix (74) is formed in a grid shape on one side of the transparent cover layer (90) (S710).

[0132] For example, the transparent cover layer (90) may use a square or rectangular glass substrate having a predetermined thickness. The size of the transparent cover layer (90) may correspond approximately to the size of the TFT substrate (20).

[0133] The black matrix (74) is formed in a grid shape to form multiple cells, each cell being a sub-pixel area. In this way, a color filter is formed in a preset cell among the multiple cells of the black matrix (74) (S720).

[0134] For example, to form a first color filter (81), a red material is uniformly applied to one side of a transparent cover layer (90) on which a black matrix (74) is formed. Then, using a mask (not shown), only the areas where red should remain are exposed, and the red material is removed from the remaining areas through development.

[0135] Next, to form a second color filter (82), a green material is uniformly applied to one side of the transparent cover layer (90). Then, using a mask (not shown), only the areas where the green should remain are exposed, and the green material is removed from the remaining areas through development.

[0136] Finally, to form the second transparent resin layer (83), a transparent resin material is uniformly applied to one surface of the transparent cover layer (90). After that, a mask (not shown) is used to expose only the areas where the transparent resin should remain, and the transparent resin material is removed from the remaining areas through development.

[0137] The method of applying the color filter material and transparent resin material to the transparent cover layer (90) can be a slit method, which applies evenly to the entire surface using a printer nozzle, or a spin method, which applies by spraying liquid in the center and then rotating the plate.

[0138] When the first and second color filters (81, 82) and the second transparent resin layer (83) are formed, a grid-shaped partition (70) is formed on the upper surface of the black matrix (S730). Each cell formed by the partition (70) can be formed at a position corresponding to each cell formed by the aforementioned black matrix (74). In this case, each cell formed by the partition (70) corresponds to a sub-pixel area.

[0139] Meanwhile, according to an embodiment of the present disclosure, a process of forming a flattening layer (75) covering the first and second color filters (81, 82) and the second transparent resin layer (83) may be performed so that a partition wall (70) can be laminated on the black matrix. The upper surface of the flattening layer (75) has a degree of flatness sufficient to form the partition wall (70) at a uniform height. The flattening layer (75) may be formed from a transparent material that does not affect the transmittance, reflectance, and refractive index of light. However, according to an embodiment of the present disclosure, the flattening layer (75) may not be included in the display module (10), and the process of forming the flattening layer (75) may also be omitted.

[0140] Meanwhile, after the partition wall (70) is formed, a first color conversion layer (71) and a second color conversion layer (72) are sequentially patterned in each cell using an inkjet printing method with a color conversion material (quantum dot material) (S740).

[0141] In another way of forming the first and second color conversion layers (71, 72), similar to the method of manufacturing the color filter described above, the quantum dot material can be mixed into a photoresist and formed through coating, exposure, and development.

[0142] The first color conversion layer (71) may be composed of red quantum dots (71a) capable of emitting light in the red wavelength band, and the second color conversion layer (72) may be composed of green quantum dots (72a) capable of emitting light in the green wavelength band.

[0143] Meanwhile, each of the first and second color conversion layers (71, 72) may include a plurality of bubble particles for scattering light in the blue wavelength band emitted from the first and second micro LEDs (61, 62), respectively.

[0144] In this case, according to one embodiment of the present disclosure, the diameter of any one of the plurality of bubble particles may be 0.74 μm to 1.26 μm.

[0145] In addition, according to one embodiment of the present disclosure, a plurality of bubble particles may be bubble particles of an inert gas. For example, the plurality of bubble particles may be spherical bubble particles of Ar, N2, etc.

[0146] Meanwhile, according to one embodiment of the present disclosure, the volume fraction of the plurality of bubble particles for each of the first and second color conversion layers (71, 72) may be 5.3% to 9%. Specifically, the volume occupied by the plurality of bubble particles (71b) within the total volume of the first color conversion layer (71) may be 5.3% to 9%.

[0147] Meanwhile, after patterning the first and second color conversion layers (71, 72) in each cell, a transparent resin material is patterned in the empty cells where the first and second color conversion layers (71, 72) are not formed using an inkjet printing method to form the first transparent resin layer (73).

[0148] A first part forming the top plate of the display module (10) can be formed through a process such as the above.

[0149] FIG. 9 is an exemplary diagram illustrating a method for manufacturing a first color-changing layer comprising a plurality of bubble particles according to one embodiment of the present disclosure.

[0150] Referring to FIG. 9, a plurality of red quantum dots (71a) and a photocurable resin material are mixed in a chamber (200) containing an inert gas. Specifically, after the plurality of red quantum dots (71a) are incorporated into the photocurable resin material, the photocurable material containing the plurality of red quantum dots (71a) is placed in a chamber containing an inert gas, and then a stirring process is performed on the photocurable material containing the plurality of red quantum dots (71a). As a result, a plurality of bubble particles (71b) of the inert gas can be generated within the photocurable resin material. Meanwhile, the inert gas may be a gas such as Ar or N2. Meanwhile, the above-described method is applied in the same way to the second color conversion layer, so that a plurality of bubble particles (72b) can be generated within the photocurable resin material constituting the second color conversion layer.

[0151] FIG. 10 is a flowchart showing the manufacturing process of a second part of a display module according to one embodiment of the present disclosure, and FIG. 11 is a process diagram of a second part of a display module according to one embodiment of the present disclosure. FIG. 11 does not show the entire second part of the display module (10), but shows an enlarged view of a part corresponding to a single pixel. Here, the second part may be a part of the display module (10) that includes a plurality of self-emissive elements on a first substrate and may be a part that constitutes the lower surface or bottom plate of the display module.

[0152] Referring to FIGS. 10 and 11, an anisotropic conductive film (50) is laminated onto the front surface of a TFT substrate (20) (S1010). In this case, a plurality of substrate electrode pads (26a, 26b) are arranged at regular intervals on the front surface of the TFT substrate (20).

[0153] After attaching an anisotropic conductive film (50) to a TFT substrate (20), a plurality of micro LEDs are transferred to the TFT substrate (20) (S1020). The micro LED transfer process can be performed using a laser transfer method, a rollable transfer method, a pick-and-place transfer method, etc. In this case, the first to third micro LEDs (61, 62, 63) are each transferred from an epitaxial substrate to a relay substrate (or interposer), and then transferred from each relay substrate to a target substrate, which is a TFT substrate (20).

[0154] When the first to third micro LEDs (61, 62, 63) are transferred to the TFT substrate (20), they are placed on the surface of the anisotropic conductive film (50) attached to the TFT substrate (20). In this state, the first to third micro LEDs (61, 62, 63) are inserted into the anisotropic conductive film (50) to a predetermined depth through a thermal compression process. Accordingly, the first to third micro LEDs (61, 62, 63) are physically fixed to the TFT substrate (20). Additionally, the chip electrodes of each micro LED (61, 62, 63) can be electrically connected to the corresponding substrate electrode pads by a plurality of conductive balls distributed within the anisotropic conductive film (50).

[0155] The first to third micro LEDs (61, 62, 63) may be blue micro LEDs that emit light in the blue wavelength band.

[0156] Next, an optical adhesive (65) for bonding the first and second parts is applied to the front surface of the TFT substrate (20) (S1030).

[0157] The optical adhesive (65) is applied to the TFT substrate (20) so as to cover all of the multiple micro LEDs (61, 62, 63). The optical adhesive (65) may be a UV-curing silicone rubber (chemical formula: Di-methyl siloxane) having the characteristic of curing after a certain period of time following UV exposure.

[0158] Next, the optical adhesive (65) is cured by irradiating it with UV light for a preset time (S1040).

[0159] Through this process, a second part forming the bottom plate of the display module (10) can be formed.

[0160] The following describes a process for manufacturing a display module (10) by joining the first part and the second part together.

[0161] FIG. 12 is a process diagram for combining a first part and a second part of a display module according to one embodiment of the present disclosure.

[0162] Meanwhile, step S630 in FIG. 7 may further include the step of aligning the first substrate and the second substrate such that the first color conversion layer corresponds to the first self-luminous element, the second color conversion layer corresponds to the second self-luminous element, and the transparent resin layer corresponds to the third self-luminous element.

[0163] Specifically, referring to FIG. 12, after the second part is seated on a die (not shown), the first part is placed on the upper side of the second part at a predetermined distance.

[0164] Next, in order to bond the first and second parts (11, 12) together, the first part is inverted so that the first and second color conversion layers (71, 72) of the first part correspond to the first and second micro LEDs (61, 62) of the second part, and the first transparent resin layer (73) corresponds to the third micro LED (63), so that they are aligned to a bonding position.

[0165] In this case, it is preferable that the first and second parts (11, 12) be arranged to remain parallel to each other on the same plane.

[0166] After the first and second parts (11, 12) are aligned to the bonding position, the first part is pressed against the second part with a preset pressure to bond the first and second parts (11, 12). In this case, the first and second parts (11, 12) are bonded to each other by an optical adhesive (65).

[0167] After bonding the first and second parts (11, 12), the optical adhesive (65) can be cured to strengthen the bond between the first and second parts (11, 12).

[0168] A display module (10) according to one embodiment of the present disclosure can be manufactured through such a process.

[0169] Although various embodiments of the present disclosure have been described individually above, each embodiment is not required to be implemented alone, and the configuration and operation of each embodiment may be implemented in combination with at least one other embodiment.

[0170] Although preferred embodiments of the present disclosure have been illustrated and described above, the present disclosure is not limited to the specific embodiments described above. It is understood that various modifications can be made by those skilled in the art without departing from the essence of the present disclosure as claimed in the claims, and such modifications should not be understood individually from the technical spirit or perspective of the present disclosure. Explanation of the symbols

[0171] 10: Display module 20: TFT substrate 61, 62, 63: Blue Micro LED 71: First color conversion layer 72: Second color conversion layer 73: First transparent resin layer 74: Black Matrix 81: First color filter 82: Second color filter 83: Second transparent resin layer 90: Transparent cover layer

Claims

Claim 1 A substrate; and a plurality of pixels formed on the substrate; wherein each of the plurality of pixels comprises: a first, second, and third self-luminescent element emitting light of a first wavelength band; a first color conversion layer disposed on the first self-luminescent element and comprising a plurality of first quantum dots that absorb light of a first wavelength band emitted from the first self-luminescent element and emit light of a second wavelength band; and a second color conversion layer disposed on the second self-luminescent element and comprising a plurality of second quantum dots that absorb light of a first wavelength band emitted from the second self-luminescent element and emit light of a third wavelength band; and wherein each of the first color conversion layer and the second color conversion layer is titanium dioxide ( ), silicon dioxide( A display module comprising a plurality of scattering particles of a non-gaseous material such as zirconium oxide (ZrO) or glass beads, wherein each of the first and second color conversion layers comprises a plurality of bubble particles for scattering light emitted from the first and second self-luminous elements, respectively, and wherein the plurality of bubble particles comprises bubble particles of an inert gas. Claim 2 A display module according to claim 1, wherein the diameter of any one of the plurality of bubble particles is 0.74 μm to 1.26 μm. Claim 3 In claim 1, the plurality of bubble particles are argon (Ar) or nitrogen ( )-in, display module. Claim 4 A display module according to claim 1, wherein the volume fraction of the plurality of bubble particles for each of the first and second color conversion layers is 5.3% to 9%. Claim 5 In claim 1, the plurality of scattering particles are titanium dioxide ( , silicon dioxide( A display module, which is one of ), zirconium oxide (ZrO), or glass beads. Claim 6 A display module according to claim 5, wherein the mass ratio of the plurality of first quantum dots and the plurality of scattering particles included in the first color conversion layer is 1:0.04 to 1:0.14, and the mass ratio of the plurality of second quantum dots and the plurality of scattering particles included in the second color conversion layer is 1:0.04 to 1:0.

14. Claim 7 In claim 1, the first, second, and third self-luminous elements are blue micro light-emitting diodes, in a display module. Claim 8 A display module according to claim 1, wherein the plurality of first quantum dots absorb light of a blue wavelength and emit light of a red wavelength, and the plurality of second quantum dots absorb light of a blue wavelength and emit light of a green wavelength. Claim 9 A display module according to claim 1, further comprising: a first color filter disposed on the first color conversion layer; and a second color filter disposed on the second color conversion layer. Claim 10 A display module according to claim 9, further comprising: a first transparent resin layer disposed on the third self-emissive element; and a second transparent resin layer disposed on the plane where the first and second color filters are located, when disposed on the first color conversion layer. Claim 11 A method for manufacturing a display module comprises: mounting first to third self-emissive elements corresponding to a plurality of subpixels on a first substrate; forming first and second color conversion layers containing a plurality of bubble particles in regions corresponding to the first and second self-emissive elements among regions partitioned by a plurality of partitions formed on a second substrate, and forming a transparent resin layer in a region corresponding to the third self-emissive element among regions partitioned by the plurality of partitions; and the step of bonding the first substrate and the second substrate in close contact to bond the plurality of color conversion layers onto the first and second self-luminous elements, and bonding the transparent resin layer onto the third self-luminous element; wherein the first color conversion layer comprises a plurality of first quantum dots that absorb light of a first wavelength band emitted from the first self-luminous element and emit light of a second wavelength band, and the second color conversion layer comprises a plurality of second quantum dots that absorb light of the first wavelength band emitted from the second self-luminous element and emit light of a third wavelength band, and each of the first color conversion layer and the second color conversion layer is titanium dioxide ( ), silicon dioxide( A manufacturing method comprising a plurality of scattering particles of a non-gaseous material such as ), zirconium oxide (ZrO), or glass beads, wherein light emitted from each of the first and second self-luminous elements is scattered by a plurality of bubble particles included in the first and second color conversion layers and the plurality of scattering particles. Claim 12 A manufacturing method according to claim 11, wherein the forming step comprises: forming a plurality of black matrices at predetermined intervals on a second substrate; forming a color filter between the plurality of black matrices formed on the second substrate; and forming a partition on each black matrix to divide it into regions corresponding to a plurality of subpixels. Claim 13 A manufacturing method according to claim 11, further comprising the step of aligning the first substrate and the second substrate such that the first color conversion layer corresponds to the first self-luminous element, the second color conversion layer corresponds to the second self-luminous element, and the transparent resin layer corresponds to the third self-luminous element. Claim 14 A manufacturing method according to claim 11, wherein the diameter of any one of the plurality of bubble particles is 0.74 μm to 1.26 μm. Claim 15 In Clause 11, the plurality of bubble particles are argon (Ar) or nitrogen ( )person, manufacturing method. Claim 16 A manufacturing method according to claim 11, wherein the volume fraction of the plurality of bubble particles for each of the first and second color conversion layers is 2.5% to 9%. Claim 17 In paragraph 11, the plurality of scattering particles are titanium dioxide ( ), silicon dioxide( A method of manufacturing one of ), zirconium oxide (ZrO), or glass beads. Claim 18 A method of manufacturing according to claim 17, wherein the mass ratio of the plurality of first quantum dots and the plurality of scattering particles included in the first color conversion layer is 1:0.04 to 1:0.14, and the mass ratio of the plurality of second quantum dots and the plurality of scattering particles included in the second color conversion layer is 1:0.04 to 1:0.

14. Claim 19 A method of manufacturing in claim 11, wherein the first, second, and third self-luminous elements are Blue Micro Light Emitting Diodes. Claim 20 A method of manufacturing according to claim 11, wherein the plurality of first quantum dots absorb light of a blue wavelength and emit light of a red wavelength, and the plurality of second quantum dots absorb light of a blue wavelength and emit light of a green wavelength.

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