Display module including color conversion layer formed on self-emitting device and method of manufacturing same

Abstract

The invention provides a display module. The display module includes: a substrate; and a plurality of pixels on the substrate, in which each of the plurality of pixels includes: a first self-emitting element, a second self-emitting element, and a third self-emitting element configured to emit light of a first wavelength band, respectively; a first color conversion layer configured to be disposed on the first self-luminous element, and including a plurality of first quantum dots for absorbing light of a first wavelength band emitted from the first self-luminous element and emitting light of a second wavelength band; and a second color conversion layer configured to be disposed on the second self-luminous element and including a plurality of second quantum dots for absorbing light of the first wavelength band emitted from the second self-luminous element and emitting light of a third wavelength band, in which the first color conversion layer and the second color conversion layer include a plurality of foam particles, the plurality of foam particles are configured to scatter light emitted from the first self-luminous element and light emitted from the second self-luminous element.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a display module and a method for manufacturing the display module, and more particularly, to a display module including a self-luminous element and a color conversion layer formed on the self-luminous element and a method for manufacturing the display module. Background Art

[0002] Recently, with the development of electronic technology, the use of display modules and display devices that display images by using quantum dots has increased. The quantum dots absorb light emitted by a self-luminous element included in the display module, and then emit light of a wavelength range different from the absorbed light. Here, the quantum dots may be included in a color conversion layer formed on the self-luminous element, and in the case of a quantum dot-based display, a plurality of scattering particles are included together in the color conversion layer including the quantum dots. The plurality of scattering particles play a role in scattering light that is not absorbed by the quantum dots and is emitted. Summary of the invention

[0003] Technical Solution

[0004] According to one aspect of the embodiment, a display module is provided, which includes: a substrate; and a plurality of pixels on the substrate, wherein each of the plurality of pixels includes: a first self-luminous element, a second self-luminous element, and a third self-luminous element, each configured to emit light of a first band; a first color conversion layer, configured to be disposed on the first self-luminous element, and including a plurality of first quantum dots for absorbing light of the first band emitted from the first self-luminous element and emitting light of a second band; and a second color conversion layer, configured to be disposed on the second self-luminous element, and including a plurality of second quantum dots for absorbing light of the first band emitted from the second self-luminous element and emitting light of a third band, wherein the first color conversion layer and the second color conversion layer include a plurality of foam particles, and the plurality of foam particles are configured to scatter light emitted from the first self-luminous element and light emitted from the second self-luminous element.

[0005] A diameter of each foam particle among the plurality of foam particles may be between 0.74 μm and 1.26 μm.

[0006] The plurality of foam particles may be foam particles of an inert gas.

[0007] A volume fraction of the plurality of foam particles for each of the first color conversion layer and the second color conversion layer may be between 5.3% and 9%.

[0008] Each of the first color conversion layer and the second color conversion layer may also include a plurality of scattering particles.

[0009] A mass ratio of the plurality of first quantum dots included in the first color conversion layer to the plurality of scattering particles may be between 1:0.04 and 1:0.14, and a mass ratio of the plurality of second quantum dots included in the second color conversion layer to the plurality of scattering particles may be between 1:0.04 and 1:0.14.

[0010] The first self-luminous element, the second self-luminous element and the third self-luminous element may be blue micro light emitting diodes.

[0011] The plurality of first quantum dots may be configured to absorb light in a blue wavelength band and emit light in a red wavelength band, and the plurality of second quantum dots may be configured to absorb light in a blue wavelength band and emit light in a green wavelength band.

[0012] The display module may further include: a first color filter on the first color conversion layer; and a second color filter on the second color conversion layer.

[0013] The display module may further include: a first transparent resin layer on the third self-luminous element; and a second transparent resin layer on the first color conversion layer, wherein the second transparent resin layer, the first color filter, and the second color filter are on the same plane.

[0014] According to another aspect of the embodiment, a method for manufacturing a display module is provided, the method comprising: forming a first self-luminous element, a second self-luminous element, and a third self-luminous element corresponding to a plurality of sub-pixels on a first substrate; forming a first color conversion layer and a second color conversion layer including a plurality of foam particles in a region corresponding to the first self-luminous element and the second self-luminous element among regions separated by a plurality of partitions formed on the second substrate; forming a transparent resin layer in a region corresponding to the third self-luminous element among regions separated by a plurality of partitions; and bonding the first substrate and the second substrate to each other, bonding the plurality of color conversion layers to the first self-luminous element and the second self-luminous element, and bonding the transparent resin layer to the third self-luminous element, wherein the first color conversion layer comprises a plurality of first quantum dots configured to absorb light of a first wavelength band emitted from the first self-luminous element and emit light of a second wavelength band, wherein the second color conversion layer comprises a plurality of second quantum dots configured to absorb light of a first wavelength band emitted from the second self-luminous element and emit light of a third wavelength band, and wherein light emitted from the first self-luminous element and light emitted from the second self-luminous element are scattered by a plurality of foam particles included in the first color conversion layer and the second color conversion layer.

[0015] The manufacturing method may further include: forming a plurality of black matrices at predetermined intervals on the second substrate; forming a color filter between the plurality of black matrices formed on the second substrate; and forming a partition on each of the plurality of black matrices to correspond to the plurality of sub-pixels.

[0016] The manufacturing method may further include bonding the first substrate and the second substrate to each other so 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.

[0017] A diameter of each foam particle among the plurality of foam particles may be between 0.74 μm and 1.26 μm.

[0018] The plurality of foam particles may be foam particles of an inert gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other aspects, features and advantages of the embodiments of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0020] Figure 1 is a schematic front view showing a display module according to an embodiment;

[0021] Figure 2 is a schematic block diagram showing a display module according to an embodiment;

[0022] Figure 3 is a cross-sectional view showing a single pixel of a display module including a foam particle-based color conversion layer according to one or more embodiments;

[0023] Figure 4 is a cross-sectional view showing a single pixel of a display module including a color conversion layer based on foam particles and scattering particles according to one or more embodiments;

[0024] Figure 5 is a graph showing a brightness maintenance rate of a display module including a foam particle-based color conversion layer according to one or more embodiments;

[0025] Figure 6 is a schematic sequence diagram showing a method for manufacturing a display module according to one or more embodiments;

[0026] Figure 7 is a flow chart showing a manufacturing process of a first portion of a display module according to one or more embodiments;

[0027] Figure 8 is a process diagram of a first portion of a display module according to one or more embodiments;

[0028] Fig. 9 is an exemplary diagram illustrating a method of manufacturing a first color conversion layer including a plurality of foam particles according to one or more embodiments;

[0029] Fig.10 is a flow chart showing a manufacturing process of a second portion of a display module according to one or more embodiments;

[0030] Fig.11 is a process diagram of a second portion of a display module according to one or more embodiments; and

[0031] Fig.12 is a diagram of a process of coupling a first portion and a second portion of a display module according to one or more embodiments. DETAILED DESCRIPTION

[0032] First, terms used in the specification will be briefly described, and then the present disclosure will be described in detail.

[0033] The embodiments described herein are example embodiments, and thus, the present disclosure is not limited thereto.

[0034] As the terms used in the embodiments of the present disclosure, in view of the functions described in the present disclosure, currently widely used general terms are selected as much as possible. However, these terms may change according to the intentions of those skilled in the art, previous court decisions or the emergence of new technologies, etc. In addition, in certain cases, there may be terms arbitrarily specified by the applicant, and in this case, the meaning of the terms will be described in detail in the relevant description of the present disclosure. Therefore, the terms used in the present disclosure should be defined based on the meaning of the terms and the overall content of the present disclosure rather than just based on the names of the terms.

[0035] Furthermore, in this specification, expressions such as “having”, “may have”, “including”, and “may include” indicate the existence of such features (for example, elements such as numbers, functions, operations, and components) and do not exclude the existence of additional features.

[0036] In addition, the expression “at least one of A and / or B” should be interpreted as any one of “A” or “B” or “A and B”.

[0037] In addition, the expressions "first", "second", etc. used in this specification can describe various elements without regard to any order and / or importance. In addition, such expressions are only used to distinguish one element from another element and are not intended to limit the elements.

[0038] In addition, the description that one element (e.g., a first element) in the present disclosure is “(operably or communicatively) coupled to” or “connected to” another element (e.g., a second element) should be interpreted as including the following two cases: a case where one element is directly coupled to another element and a case where one element is coupled to another element via yet another element (e.g., a third element).

[0039] In addition, singular expressions include plural expressions unless clearly defined differently in the context. In addition, in the present disclosure, terms such as "including" and "consisting of" should be interpreted as indicating the presence of the features, numbers, steps, operations, elements, components, or combinations thereof described in the specification, but do not preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, elements, components, or combinations thereof.

[0040] In addition, in the present disclosure, a "module" or "part" performs at least one function or operation and can be implemented as hardware or software, or a combination of hardware and software. In addition, in addition to the "module" or "part" that needs to be implemented as specific hardware, multiple "modules" or multiple "parts" can be integrated into at least one module and implemented as at least one processor (not shown).

[0041] In the present disclosure, a display module may be a display module including a micro light emitting diode ("micro LED"), which is a self-luminous element for displaying an image. A display module is a flat display panel that is composed of a plurality of inorganic light emitting diodes (inorganic LEDs), each of which is less than or equal to 100 microns, and provides better contrast, response time, and energy efficiency than a liquid crystal display ("LCD") that requires a backlight. In a display module, since the micro LED for displaying an image is a self-luminous element, there is no need to include a separate backlight.

[0042] In the present disclosure, micro-LEDs as inorganic LEDs have better brightness and luminous efficiency than organic LEDs ("OLEDs"), and have a longer lifespan. Micro-LEDs may be semiconductor chips that can emit light by themselves when powered. Micro-LEDs have fast response speed, low power consumption, and high brightness. For example, micro-LEDs have higher efficiency in converting electricity into photons than conventional LCDs or OLEDs. That is, micro-LEDs have higher "brightness per watt" than conventional LCD or OLED displays. Therefore, compared with conventional LEDs (whose length, width, and height are respectively more than 100 μm) or OLEDs, micro-LEDs can play the same brightness with about half the energy. In addition, micro-LEDs can achieve high resolution, excellent color, contrast, and brightness, and therefore, they can correctly express a wide range of colors and can achieve a clear screen outdoors. In addition, micro-LEDs are strongly resistant to aging phenomena and generate little heat, so long life can be guaranteed without deformation. Micro-LEDs may have a flip-chip structure in which an anode electrode 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 on which the electrodes are formed.

[0043] In the present disclosure, one pixel may include at least three sub-pixels. One sub-pixel is a self-luminous element for displaying an image, and it may represent, for example, a micro-LED, a blue micro-light emitting diode (blue LED), or an ultraviolet micro-light emitting diode (UV micro-LED). Here, the blue micro-LED is a self-luminous element that emits light in the blue band (450-490nm), and the UV micro-LED may be a self-luminous element that emits light in the ultraviolet band (360-410nm).

[0044] In the present disclosure, a sub-pixel may include a micro self-luminous element and a color conversion layer and a color filter corresponding thereto. The color conversion layer may be excited by light emitted from the micro self-luminous element and emit a color of a specific wavelength band. The color conversion layer may be composed of a material including nano phosphor or quantum dots.

[0045] In the present disclosure, a sub-pixel region refers to a region where the color of the sub-pixel is expressed by light emitted from the sub-pixel. In addition, in the present disclosure, the area (horizontal length×vertical length) of one surface of the color conversion layer corresponding to the sub-pixel may be greater than the area of ​​the light emitting surface of the sub-pixel. In this case, the sub-pixel region may correspond to the region of the color conversion layer.

[0046] In the present disclosure, a thin film transistor (TFT) layer on which a thin film transistor (TFT) circuit is formed may be disposed on the front surface of the substrate, and a power supply circuit and a data drive driver, a gate drive driver, and a timing controller for controlling each drive driver for supplying power to the TFT circuit may be disposed on the rear surface. A plurality of pixels arranged on the TFT layer may be driven by the TFT circuit.

[0047] In the present disclosure, for the substrate, a glass substrate, a synthetic resin-based substrate (eg, polyimide (PI), polyethylene terephthalate (PET), polyethersulfone (PES), polyethylene naphthalate (PEN), polycarbonate (PC), etc.), or a ceramic substrate may be used.

[0048] In the present disclosure, a TFT layer on which a TFT circuit is formed may be provided on the front surface of the substrate, and the circuit may not be provided on the rear surface of the substrate. The TFT layer may be formed as an integral body on the substrate, or may be manufactured in the form of a separate film and attached to one surface of the glass substrate.

[0049] In the present disclosure, the front surface of the substrate can be divided into an active area and a dummy area. The active area can correspond to the area occupied by the TFT layer on the front surface of the substrate, and the dummy area can be an area other than the area occupied by the TFT layer on the front surface of the substrate.

[0050] In the present disclosure, the edge region of the substrate may be the outermost region of the glass substrate. In addition, the edge region of the substrate may be the remaining region except the region where the circuit of the substrate is formed. In addition, 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 into a quadrilateral type. For example, the substrate may be formed into a rectangle or a square. The edge region of the substrate may include at least one of the four sides of the glass substrate.

[0051] In the present disclosure, the TFTs constituting the TFT layer (or backplane) are not limited to a specific structure or type. For example, the TFTs listed in the present disclosure may be implemented as oxide TFTs, Si TFTs (polycrystalline silicon, amorphous silicon), organic TFTs, graphene TFTs, etc., in addition to low-temperature polycrystalline silicon (LTPS) TFTs, and may be manufactured using only Si wafer CMOS processes and may use P-type (or N-type) MOSFETs.

[0052] 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 electrically connected to each micro LED according to the AM driving method or the PM driving method.

[0053] In the present disclosure, a plurality of pulse amplitude modulation (PAM) control circuits may be provided in one pixel region. In this case, each sub-pixel provided in one pixel region may be controlled by a corresponding PAM control circuit. In addition, a plurality of pulse width modulation (PWM) control circuits may be provided in one pixel region. In this case, each sub-pixel provided in one pixel region may be controlled by a corresponding PWM control circuit.

[0054] In the present disclosure, a plurality of PAM control circuits and a plurality of PWM control circuits may be arranged together in one pixel region. In this case, some of the sub-pixels arranged in one pixel region may be controlled by the PAM control circuit, and other sub-pixels may be controlled by the PWM control circuit. In addition, each sub-pixel may be controlled by both the PAM control circuit and the PWM control circuit.

[0055] In the present disclosure, the display module may include a plurality of side surface wirings having a thin film thickness disposed at certain intervals along a side surface of a TFT substrate.

[0056] In the present disclosure, in the display module, a plurality of penetration wiring members formed not to be exposed on the side surface of the TFT substrate may be provided instead of the side surface wiring exposed on the side surface of the TFT substrate. Accordingly, the dummy area may be minimized on the front surface of the substrate of the TFT, and the active area may be maximized, and thus, the display module may become frameless, and the mounting density of the micro LEDs of the display module may be increased.

[0057] In the present disclosure, when multiple display modules of a frameless structure are connected, a large-size multi-display device that can maximize the active area can be provided. In this case, since the dummy area in each display module is minimized, the spacing between each pixel of the display modules adjacent to each other can be formed to be the same as the spacing between each pixel in a single display module. Therefore, this can be a method of making the seam in the connection portion between each display module invisible.

[0058] In the present disclosure, the driving circuit can be implemented by a micro IC that is arranged in a pixel area and controls the driving of at least 2n pixels. When the micro IC is applied to a display module, only a channel layer that connects the micro IC to each micro LED can be formed instead of a TFT on a TFT layer (or backplane).

[0059] In the present disclosure, the display module can be installed as a single unit and applied to wearable devices, portable devices, handheld devices, and various electronic products or electronic devices that require display, and can also be applied to display devices as a matrix type through multiple assembly arrangements, such as personal computer (PC) displays, high-resolution TVs and signs (or, digital signage), electronic displays, etc.

[0060] Hereinafter, the present disclosure will be described in detail with reference to the accompanying drawings.

[0061] Figure 1 is a schematic front view showing a display module according to an embodiment, and Figure 2 is a schematic block diagram showing a display module according to an embodiment.

[0062] Reference Figure 1 and Figure 2 The display module 10 according to the embodiment may include a TFT substrate 20 on which a plurality of pixel driving circuits 30 are formed, a plurality of pixels 100 on a front surface of the TFT substrate 20 , and a panel driving part 40 that generates a control signal and provides the generated control signal to the plurality of pixel driving circuits 30 .

[0063] In an embodiment, a pixel may include a plurality of sub-pixels. In addition, a sub-pixel may include a self-luminous element and a color conversion layer and a color filter corresponding to each self-luminous element. Here, the self-luminous element is an inorganic self-luminous diode, and may be, for example, a vertical cavity surface emitting laser (VCSEL) diode or a micro light emitting diode (LED) having a size less than or equal to 100 μm (e.g., less than or equal to 30 μm). The VCSEL diode and the micro LED may emit light in the blue band (450-490 nm) or emit light in the ultraviolet band (360-410 nm). The following will refer to Figure 3 The structure of the pixel 100 is described in detail.

[0064] The TFT substrate 20 may include a glass substrate 21 , a TFT layer 23 including a thin film transistor (TFT) circuit on the front surface of the glass substrate 21 , and a plurality of side surface wirings 25 electrically connecting the TFT circuit of the TFT layer 23 with a circuit disposed on the rear surface of the glass substrate.

[0065] In an embodiment, as an alternative to the glass substrate 21, a substrate made of a synthetic resin having a flexible material (e.g., polyimide (PI), polyethylene terephthalate (PET), polyether sulfone (PES), polyethylene naphthalate (PEN), polycarbonate (PC), etc.) or a ceramic substrate may be used.

[0066] The TFT substrate 20 may include an active area 20 a that provides an image on a front surface, and a dummy area 20 b that may not provide an image.

[0067] The active area 20a may be divided into a plurality of pixel areas 24. The plurality of pixel areas 24 may be divided into various forms. For example, the plurality of pixel areas may be divided into a matrix form. In one pixel area 24, one pixel 100 (see Figure 3 ).

[0068] The dummy region 20b may be included in an edge region of the glass substrate, and a plurality of connection pads 28a arranged at regular intervals may be formed along the edge region. Each of the plurality of connection pads 28a may be electrically connected to each pixel driving circuit 30 through a wiring 28b.

[0069] The number of connection pads 28a formed in the dummy region 20b may vary according to the number of pixels implemented in the glass substrate 21, and may also vary according to the driving method of the TFT circuit provided in the active region 20a. For example, an active matrix (AM) driving method that independently drives each pixel may require more wiring and connection pads than the case of a passive matrix (PM) driving method in which a TFT circuit provided in the active region 20a drives a plurality of pixels on horizontal and vertical lines.

[0070] The TFT layer 23 may include a plurality of data signal lines arranged horizontally for controlling the 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.

[0071] The panel driving part 40 may be directly connected to the substrate by a chip on glass (COG) or chip on plastic (COP) bonding method, or indirectly connected to the TFT substrate 20 via a separate FPCB by a film on glass (FOG) bonding method. The panel driving part 40 may drive the plurality of pixel driving circuits 30 and control light emission of a plurality of micro LEDs electrically connected to each of the plurality of pixel driving circuits 30.

[0072] The panel driving section 40 may control the plurality of pixel driving circuits 30 row by row through the first driving section 41 and the second driving section 42. The first driving section 41 may generate a control signal for sequentially controlling the plurality of horizontal lines formed on the TFT substrate 20 row by row for each image frame, and transmit the generated control signal to the pixel driving circuits 30 respectively connected to the lines. The second driving section 42 may generate a control signal for sequentially controlling the plurality of vertical lines formed on the TFT substrate 20 row by row for each image frame, and transmit the generated control signal to the pixel driving circuits 30 respectively connected to the lines.

[0073] Figure 3 is a cross-sectional view illustrating a single pixel of a display module including a foam particle-based color conversion layer according to one or more embodiments.

[0074] Reference Figure 3 , a pixel 100 may include a pixel region 24 (refer to Figure 1 ).

[0075] Each of the plurality of pixels 100 according to one or more embodiments may include a plurality of self-luminous elements emitting light of the same color. For example, the plurality of pixels 100 may include a first self-luminous element, a second self-luminous element, and a third self-luminous element emitting light of a first wavelength band.

[0076] According to one or more embodiments, the first self-luminous element, the second self-luminous element, and the third self-luminous element may be micro-LEDs (first micro-LED, second micro-LED, and third micro-LED) that respectively emit light in the blue band (450-490nm). Here, each micro-LED may correspond to each sub-pixel included in the pixel 100. As an 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, it will be assumed that the first self-luminous element, the second self-luminous element, and the third self-luminous element according to the present disclosure are micro-LEDs that emit light in the blue band for explanation. Therefore, the first self-luminous element will be referred to as the first micro-LED, the second self-luminous element will be referred to as the second micro-LED, and the third self-luminous element will be referred to as the third micro-LED.

[0077] The first micro LED 61 and the second micro LED 62 can be vertical cavity surface emitting laser (VCSEL) diodes, so that light is not emitted to the rear surface (the surface where the chip electrodes are located) and the side surface of the first micro LED 61 and the second micro LED 62, but is emitted only to the light emitting surface in a direction perpendicular to the surface of the TFT substrate 20.

[0078] The first micro LED 61 , the second micro LED 62 , and the third micro LED 63 may be electrically and physically connected to the TFT substrate 20 through an anisotropic conductive film (ACF) 50 laminated on the front surface of the TFT substrate 20 .

[0079] An anisotropic conductive film may be formed on the TFT substrate 20. Here, the anisotropic conductive film 50 may include a thermosetting resin (epoxy resin, polyurethane resin, acrylic resin, etc.) and a plurality of conductive balls with a relatively small diameter (e.g., 3-15 μm) inside the thermosetting resin. Each conductive ball may include polymer particles and a conductive film coated on the surface of the polymer particles, such as gold (Au), nickel (Ni), palladium (Pd), etc. The anisotropic conductive film 50 has conductivity in the compression direction and insulation in the perpendicular direction to the compression direction.

[0080] The first micro LED 61, the second micro LED 62, and the third micro LED 63 may have a flip chip structure in which two chip electrodes 61a, 61b (i.e., an anode electrode and a cathode electrode) are formed on opposite sides of a light emitting surface. The first chip electrode 61a and the second chip electrode 61b may be composed of any one of aluminum (Al), titanium (Ti), chromium (Cr), Ni, Pd, silver (Ag), germanium (Ge), or Au, or an alloy thereof.

[0081] When the first micro LED 61, the second micro LED 62, and the third micro LED 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. Then, through a heat pressing process, the first micro LED 61, the second micro LED 62, and the third micro LED 63 are inserted into the inside of the anisotropic conductive film 50 to a predetermined depth. Therefore, the first micro LED 61, the second micro LED 62, and the third micro LED 63 can be physically fixed on the TFT substrate 20 by the anisotropic conductive film 50.

[0082] Furthermore, when the first micro LED 61 is pressed toward the TFT substrate 20 by the heat pressing 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 through conductive balls located between the chip electrodes 61a, 61b of the first micro LED 61 and the substrate electrode pads. Similarly, the second micro LED 62 and the third micro LED 63 may also be electrically connected to the substrate electrode pads corresponding to each chip electrode through conductive balls in the same manner as the first micro LED 61.

[0083] The first color conversion layer may be disposed on the first self-luminous 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. In addition, the second color conversion layer may be disposed on the second self-luminous element. Here, 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.

[0084] For example, the first color conversion layer 71 includes a first quantum dot 71b that absorbs light of a first wavelength band emitted from the first micro LED 61 and emits light of a second wavelength band. In addition, the second color conversion layer 72 includes a second quantum dot 72b that absorbs light of a third wavelength band emitted from the second micro LED 62 and emits light of a second wavelength band.

[0085] According to one or more embodiments, the first color conversion layer 71 may be composed of a material including red quantum dots 71a that absorbs light in a blue band emitted from the blue micro LEDs 61 and emits light in a red band. In addition, the second color conversion layer 72 may be composed of a material including green quantum dots that absorbs light in a blue band emitted from the blue micro LEDs and emits light in a green band.

[0086] Here, quantum dots may be small spherical semiconductor particles of nanometer (nm) size and may have a size between about 2nm and 10nm. The quantum dots may be composed of a central body and a surface, the central body being composed of cadmium selenide (CdSe), cadmium telluride (CdTe) or cadmium sulfide (CdS), etc., and the surface being composed of zinc sulfide (ZnS).

[0087] The band gap between the valence band and the conduction band varies according to the size of the quantum dot. For example, if the size of the quantum dot becomes smaller than the Bohr radius (for example, if the size of the quantum dot becomes smaller than 10 nm), the band gap increases due to the quantum confinement effect. As the band gap increases more, the quantum dot emits light with a shorter wavelength. For example, according to the size of the quantum dot, the wavelength of light emitted from the quantum dot may vary. 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.

[0088] Hereinafter, for the convenience of description of the present disclosure, it will be described assuming that the light of the second wavelength band is red light and the light of the third wavelength band is green light.

[0089] As an alternative to the first quantum dots and the second quantum dots, the first color conversion layer 71 and the second color conversion layer 72 may include nano phosphors that absorb light emitted from the first micro LED 61 and the second micro LED 62, and convert the light into light of different wavelength bands and emit the light. Compared with related phosphors having a particle size of several tens of μm, nano phosphors exhibit different physical properties. For example, since the energy band gap (which is the quantum state energy level structure of electrons inside the nano phosphor crystal) is large, the wavelength of the emitted light has high energy, and thus the luminous efficiency can be improved. In the nano phosphor, the particle density of the phosphor is increased compared to the phosphor having a block structure in the application area, and accordingly, the colliding electrons effectively contribute to light emission, so the efficiency of the display can be improved.

[0090] The first color conversion layer 71 may include a red nano phosphor that is excited by the light of the blue wavelength band emitted from the first micro LED 61 and may emit light of the red wavelength band. For example, the red nano phosphor may be SCASN (Si 1-x Ca x AlSiN 3 :Eu 2+ In this case, the average particle size distribution of the red nano phosphor (d 50 ) can be less than 0.5 μm (for example, 0.1 μm < d 50 <0.5μm).

[0091] The second color conversion layer 72 may include green nano phosphors that are excited by the light in the blue wavelength band emitted from the second micro LEDs 62 and may emit light in the green wavelength band. For example, the green nano phosphors may be β-SiAlON (Si 6-z Al z O z N 8-z :Eu 2+ ) or SrGa 2 S 4 In this case, the average particle size distribution of the green nano-phosphor (d 50 ) can be less than 0.5 μm (for example, 0.1 μm < d 50 <0.5μm).

[0092] Hereinafter, for the convenience of description of the present disclosure, it will be described that the first color conversion layer 71 and the second color conversion layer 72 include a plurality of red quantum dots and a plurality of green quantum dots, respectively.

[0093] The first transparent resin layer 73 may be composed of a material that does not affect the transmittance, reflectance, and refractive index of the light emitted by the third micro LED 63, or a material that can minimize the transmittance, reflectance, and refractive index. The first transparent resin layer 73 may be composed of various transparent resins such as polycarbonate (PC), polyethersulfone (PES), polymethyl methacrylate (PMMA), polyvinyl alcohol (PVA), polyimide (PI), etc. The first transparent resin layer 73 may be omitted according to circumstances, and here, an air layer exists on the light emitting surface side of the third micro LED 63.

[0094] Each of the first color conversion layer 71 and the second color conversion layer 72 includes a plurality of foam particles 71b, 72b for scattering light emitted from the first micro LED 61 and the second micro LED 62, respectively. The plurality of foam particles 71b, 72b may be distributed inside the first color conversion layer 71 and the second color conversion layer 72, and uniformly scatter the light emitted from the first micro LED 61 and the second micro LED 62 throughout the first color conversion layer 71 and the second color conversion layer 72. For example, in order to prevent the light emitted from the first micro LED 61 and the second micro LED 62 from being absorbed into the quantum dots included in each of the first color conversion layer 71 and the second color conversion layer 72 (i.e., the plurality of red quantum dots 71a included in the first color conversion layer 71 and the plurality of green quantum dots 72a included in the second color conversion layer 72) and emitted, the plurality of foam particles 71b, 72b scatter the light emitted from each of the first micro LED 61 and the second micro LED 62. Therefore, the brightness dispersion within the sub-pixel region may be reduced, and partial degradation of the region within the sub-pixel region where light is concentrated may be prevented.

[0095] The plurality of foam particles 71 b , 72 b may be distributed according to a predetermined pattern and scatter light emitted from the first micro LED and the second micro LED within a specific range.

[0096] According to one or more embodiments, the diameter of the plurality of foam particles 71 b , 72 b included in the first color conversion layer 71 and the second color conversion layer 72 may be, for example, between 0.74 μm and 1.26 μm.

[0097] In addition, according to one or more embodiments, the plurality of foam particles 71b, 72b may be foam particles of an inert gas. As an example, the plurality of foam particles 71b, 72b may be foam particles of an inert gas (such as argon (Ar), nitrogen (N 2 ) etc.) of foam particles.

[0098] In addition, the volume fraction of the plurality of foam particles 71b, 72b for the first color conversion layer 71 and the second color conversion layer 72 may be, for example, between 2.5% and 9%. Here, the volume fraction may be the fraction of the total volume occupied by the plurality of foam particles in the volume of the corresponding color conversion layer 71, 72. The volume fraction of the plurality of foam particles 71b, 72b may be determined based on the total volume of the corresponding color conversion layer (the first color conversion layer 71 and the second color conversion layer 72) and the size, number, etc. of the plurality of foam particles 71b, 72b included in the corresponding color conversion layer (the first color conversion layer 71 and the second color conversion layer 72).

[0099] According to an embodiment, the volume fractions of the plurality of foam particles 71b, 72b included in the respective color conversion layers 71, 72 may be set differently according to the wavelength of light emitted from the respective color conversion layers 71, 72. For example, the volume fraction of the plurality of foam particles 71b, 72b included in the first color conversion layer 71 and the volume fraction of the plurality of foam particles 71b, 72b included in the second color conversion layer 72 may be different.

[0100] For example, the volume fractions of the plurality of foam particles 71b, 72b respectively included in the first color conversion layer 71 and the second color conversion layer 72 may be determined differently from each other based on the size of the quantum dots included in the first color conversion layer 71 and the second color conversion layer 72, etc. As an example, the volume fraction of the plurality of foam particles 71b in the first color conversion layer 71 including the red quantum dots 71a having a relatively large size may be smaller than the volume fraction of the plurality of foam particles 72b in the second color conversion layer 72 including the green quantum dots 72a having a relatively small size. For example, the volume fractions of the plurality of foam particles 71b, 72b for the respective first color conversion layer 71 and the second color conversion layer 72 may be differently set based on the wavelength of light emitted from the respective color conversion layers (i.e., the first color conversion layer 71 and the second color conversion layer 72).

[0101] The first color conversion layer 71 may be composed of a photocurable resin material. For example, as a photocurable resin material including a plurality of red quantum dots 71a and a plurality of foam particles 71b is applied to the first micro LED 61 and then 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 manner as the first color conversion layer 71. As an example, the photocurable resins of the first color conversion layer 71 and the second color conversion layer 72 may be epoxy resins, acrylates, methacrylates, polyurethanes, and silane resins.

[0102] Furthermore, the pixel 100 may include first and second color filters 81 and 82 corresponding to the first and second color conversion layers 71 and 72 , respectively, and include a second transparent resin layer 83 corresponding to the first transparent resin layer 73 .

[0103] The first color filter 81 may be a red color filter that transmits a wavelength of light of the same color as the color of the light of the red wavelength band emitted from the first color conversion layer 71. The second color filter 82 may be a green color filter that transmits a wavelength of light of the same color as the color of the light of the green wavelength band emitted from the second color conversion layer 72.

[0104] The second transparent resin layer 83 may be composed of a material that does not affect the transmittance, reflectance, and refractive index of light passing through the first transparent resin layer 73, or may be composed of a material that can minimize the transmittance, reflectance, and refractive index. In addition, the second transparent resin layer 83 may be an optical film that directs the light toward the front surface by refraction and reflection, thereby minimizing wasted light and improving brightness.

[0105] The first micro LED 61, the second micro LED 62, and the third micro LED 63 may be configured as a square having a certain thickness and the same width and length, or as a rectangle having different widths and lengths. Such micro LEDs may achieve a true high dynamic range (HDR), and may improve brightness and black expression, and may provide a relatively high contrast ratio compared to OLEDs. The size of the micro LED may be less than or equal to 100 μm, and for example, less than or equal to 30 μm.

[0106] Refer again Figure 3 In the pixel 100, the light emitting regions of the first micro LED 61, the second micro LED 62, and the third micro LED 63 may be separated by a partition wall 70. The partition wall 70 may be formed in a substantially lattice shape. The plurality of light emitting regions separated by the partition wall 70 may correspond to one sub-pixel region, respectively.

[0107] The upper end of partition wall 70 may be adjacent to black matrix 74, and the lower end of partition wall 70 may be adjacent to the upper surface of anisotropic conductive film 50. First color conversion layer 71, second color conversion layer 72, and first transparent resin layer 73 may be provided in each light emitting region partitioned by partition wall 70.

[0108] Therefore, light emitted to the side surface of first color conversion layer 71 corresponding to first micro LED 61 may be reflected by partition wall 70 and emitted to first color filter 81. In addition, light emitted to the side surface of second color conversion layer 72 corresponding to second micro LED 62 may be reflected by partition wall 70 and emitted to second color filter 82.

[0109] The partition wall 70 may have a white color with high light reflectivity to serve as a reflector. Here, the white color may include pure white and off-white. The off-white color may include all colors similar to white.

[0110] The partition walls 70 may also be formed of a metal material having a relatively high reflectivity so that they can function as a reflective element. In addition, a metal film having a relatively high light reflectivity may be laminated on the side surfaces of the partition walls 70 .

[0111] The light emitting surfaces of the first micro LED 61, the second micro LED 62, and the third micro LED 63 may be located at substantially the same height from the upper surface of the TFT substrate 20. In addition, the light emitting surfaces of the first micro LED 61, the second micro LED 62, and the third micro LED 63 may be located at a position higher than the lower end of the partition wall 70. In this case, portions of the side surfaces of the first micro LED 61, the second micro LED 62, and the third micro LED 63 may face the partition wall 70. Therefore, light emitted from the side surfaces of the first micro LED 61, the second micro LED 62, and the third micro LED 63 may be reflected on the partition wall 70, and emitted to the first and second color conversion layers 71 and 72 and the first transparent resin layer 73.

[0112] As described above, the partition wall 70 can reflect each of the light emitted from the side surfaces of the first micro LED 61, the second micro LED 62 and the third micro LED 63, the light emitted from the side surfaces of the first color conversion layer 71 and the second color conversion layer 72, and the light emitted from the side surface of the first transparent resin layer 73, and emit the light to the front surface of the display module 10, so that the luminous efficiency can be maximized.

[0113] A planarization layer may be provided between the first and second color conversion layers 71 and 72 and the first and second color filters 81 and 82. In addition, a planarization layer may be provided between the first and second transparent resin layers 73 and 83.

[0114] The planarization layer may be composed of a material that does not affect transmittance, reflectance, and refractive index of light passing through the first and second color conversion layers 71 and 72 and the first transparent resin layer 73 or a material that can minimize the transmittance, reflectance, and refractive index.

[0115] The space between the first color filter 81 and the second color filter 82 and the second transparent resin layer 83 may be partitioned by the black matrix 74 formed in a lattice shape. The shape of the black matrix 74 may be formed in a lattice 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.

[0116] The transparent cover layer 90 may be formed on the upper side of the first and second color filters 81 and 82 and the second transparent resin layer 83. The transparent cover layer 90 may prevent the pixel 100 from being contaminated by foreign matter and may protect the pixel 100 from being damaged by external force. A glass substrate may be applied to the transparent cover layer 90.

[0117] exist Figure 3 , only the portion of the partition wall 70 , the black matrix 74 , and the transparent cover layer 90 corresponding to one pixel unit is shown, but the partition wall 70 , the black matrix 74 , and the transparent cover layer 90 may be formed to a size substantially corresponding to that of the TFT substrate 20 .

[0118] The sizes of the first micro LED 61, the second micro LED 62, and the third micro LED 63 are respectively formed to be smaller than the sizes of the first color conversion layer 71 and the second color conversion layer 72 and the first transparent resin layer 73. Therefore, a gap may be formed between the side surfaces of the first micro LED 61, the second micro LED 62, and the third micro LED 63 and the partition wall 70.

[0119] Figure 4 is a cross-sectional view showing a single pixel of a display module including a color conversion layer based on foam particles and scattering particles according to one or more embodiments. Figure 4 The display module shown is described with reference to Figure 3 The same components as those of the above-described display module 10 will be given the same reference numerals, and description thereof will be omitted.

[0120] Reference Figure 4 The first color conversion layer 71 and the second color conversion layer 72 may further include a plurality of scattering particles. For example, the plurality of light scattering particles 71c and 72c respectively included in the first color conversion layer 71 and the second color conversion layer 72 may be made of titanium dioxide (TiO 2 ), silicon dioxide (SiO 2 ), zirconium oxide (ZrO) or glass beads, etc. A plurality of light scattering particles may be distributed inside the first color conversion layer 71 and the second color conversion layer 72, and together with the plurality of foam particles 71 b, 72 b, the light emitted from the first micro LED 61 and the second micro LED 62 is uniformly dispersed throughout the first color conversion layer 71 and the second color conversion layer 72.

[0121] Hereinafter, the plurality of scattering particles included in the first color conversion layer 71 may be referred to as first scattering particles 71 c , and the plurality of scattering particles included in the second color conversion layer 72 may be referred to as second scattering particles 72 c .

[0122] According to one or more embodiments, a mass ratio of the plurality of red quantum dots 71a included in the first color conversion layer 71 to the plurality of scattering particles may be between 1:0.04 and 1:0.14. For example, a total mass ratio of the plurality of red quantum dots 71a included in the first color conversion layer 71 to a total mass ratio of the plurality of scattering particles included in the first color conversion layer 71 may be between 1:0.04 and 1:0.14.

[0123] Similarly, the mass ratio of the plurality of green quantum dots 72a included in the second color conversion layer 72 to the plurality of scattering particles may be between 1:0.04 and 1:0.14. For example, the total mass ratio of the plurality of green quantum dots 72a included in the second color conversion layer 72 to the total mass ratio of the plurality of scattering particles included in the second color conversion layer 72 may be between 1:0.04 and 1:0.14.

[0124] According to one or more embodiments, the mass ratio of the plurality of quantum dots (first quantum dots 71a and second quantum dots 72a) included in the corresponding color conversion layer (first color conversion layer 71 and second color conversion layer 72) to the plurality of scattering particles 71c, 72c may be differently set according to the wavelength of light emitted from the quantum dots. For example, the mass ratio of the plurality of red quantum dots 71a included in the first color conversion layer 71 to the plurality of first scattering particles may be different from the mass ratio of the plurality of green quantum dots 72a included in the second color conversion layer 72 to the plurality of second scattering particles. This is because the number of the plurality of scattering particles (first scattering particles 71c and second scattering particles 72c) included in the corresponding color conversion layer (first color conversion layer 71 and second color conversion layer 72) may be determined based on the size, number, etc. of the plurality of quantum dots (first quantum dots 71a and second quantum dots 72a) included in the corresponding color conversion layer (first color conversion layer 71 and second color conversion layer 72).

[0125] Figure 5 is a graph illustrating a luminance maintenance ratio of a display module including a foam particle-based color conversion layer according to one or more embodiments.

[0126] Reference Figure 5, compared with the related display module that scatters the light that passes through the color conversion layer by using only the related scattering particles, in the case of the display module according to the present disclosure that scatters the light that passes through the color conversion layer by using a plurality of foam particles 71b, 72b, the display module has a brightness maintenance rate greater than or equal to 90% for a longer time. In this regard, in the case of the related display module that scatters the light that passes through the color conversion layer by using only the related scattering particles, the mass ratio of the plurality of quantum dots inside the color conversion layer to the plurality of scattering particles is 1:0.22. Here, in the related display module, since the plurality of scattering particles absorb the blue light emitted from the light emitting element, the blue light loss occurs. In addition, since free radicals are generated from the scattering particles that absorb the blue light, the surface of the quantum dots is damaged by the generated free radicals. Therefore, the light conversion efficiency of the plurality of quantum dots inside the color conversion layer also decreases over time. However, the display module according to the embodiment may include a plurality of foam particles inside the color conversion layer, and include a plurality of scattering particles of a smaller number than the related display module, so that the loss rate of the plurality of scattering particles to the blue light can be reduced, and the surface damage of the quantum dots to the free radicals can be reduced, so that the brightness can be maintained for a longer time.

[0127] Figure 6 is a schematic sequence diagram of a method for manufacturing a display module according to one or more embodiments of the present disclosure.

[0128] Reference Figure 6 First, in operation S610, first to third self-luminous elements corresponding to a plurality of sub-pixels are mounted on a substrate.

[0129] The first substrate may be implemented as a TFT substrate 20 on which a plurality of pixel driving circuits 30 are formed. The first to third self-luminous elements may be micro LEDs 61, 62, 63 that emit light in a blue band (450-490 nm). Each micro LED 61, 62, 63 may correspond to each sub-pixel included by the pixel 100. As an 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.

[0130] Then, in operation S620, a first color conversion layer 71 and a second color conversion layer 72 including a plurality of foam particles 71b and 72b are formed in areas corresponding to the first self-luminous element and the second self-luminous element among areas separated by a plurality of partition walls formed on the second substrate, and a transparent resin layer is formed in areas corresponding to the third self-luminous element among areas separated by a plurality of partition walls.

[0131] The second substrate may be Figure 3. For example, the second substrate may be implemented as a glass substrate. The 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 partition walls formed on the glass substrate, and the second color conversion layer 72 may be formed in a region corresponding to the second micro LED 62 among the plurality of regions.

[0132] Here, the first color conversion layer 71 may be composed of a material including red quantum dots 71a that absorb light in the blue band and emit light in the red band. In addition, the second color conversion layer 72 may be composed of a material including green quantum dots 72a that absorb light in the blue band and emit light in the green band.

[0133] Each of the first color conversion layer 71 and the second color conversion layer 72 may include a plurality of foam particles 71 b, 72 b for scattering the light of the blue wavelength band respectively emitted from the first micro LED 61 and the second micro LED 62. Therefore, the light of the blue wavelength band respectively emitted from the first self-luminous element and the second self-luminous element may be scattered by the plurality of foam particles 71 b, 72 b included in the first color conversion layer 71 and the second color conversion layer 72.

[0134] The first color conversion layer 71 may be composed of a photocurable resin material. A photocurable resin material including a plurality of red quantum dots 71a and a plurality of foam particles 71b may be applied in a region corresponding to the first micro LED 61 among a plurality of regions separated by a plurality of partition walls, and the applied curable material may be cured by irradiating light. Here, 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 manner as the first color conversion layer 71.

[0135] Here, according to one or more embodiments, a plurality of scattering particles may be further included in the first color conversion layer 71 and the second color conversion layer 72. For example, the first color conversion layer 71 may further include a plurality of first scattering particles for scattering the 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 for scattering the light in the blue wavelength band emitted from the second micro LED 62.

[0136] Here, according to one or more embodiments, a mass ratio of the plurality of first quantum dots 71a to the plurality of scattering particles 71c included in the first color conversion layer 71 may be between 1:0.04 and 1:0.14, and a mass ratio of the plurality of second quantum dots 72a to the plurality of scattering particles 72c included in the second color conversion layer 72 may be between 1:0.04 and 1:0.14.

[0137] After forming the first and second color conversion layers 71 and 72 and the transparent resin layer 73 in operation S620, the first and second substrates are abutted, and a plurality of color conversion layers (the first and second color conversion layers 71 and 72) are bonded to the first and second self-luminous elements 61 and 62, and the transparent resin layer 73 is bonded to the third self-luminous element 63 in operation S630. Here, by pressing the second substrate to one side of the first substrate, the plurality of color conversion layers may be bonded to the first and second self-luminous elements, and the transparent resin layer may be bonded to the third self-luminous element.

[0138] Figure 7 is a flowchart showing a manufacturing process of a first portion of a display module according to one or more embodiments, and Figure 8 is a process diagram of a first portion of a display module according to one or more embodiments. Figure 8 , the entire first portion of the display module 10 is not shown, but a portion corresponding to one pixel will be shown in an enlarged size.

[0139] Reference Figure 7 and Figure 8 , the first part of the display module 10 may be manufactured in the following order. Here, the first part may be a part including a black matrix, a first color conversion layer 71 and a second color conversion layer 72, a first transparent resin layer and a second transparent resin layer, a first color filter to a third color filter, and a partition wall provided on the second substrate in the display module 10, and the first part may be a part constituting an upper surface or an upper plate of the display module 10.

[0140] First, in operation S710 , a black matrix 74 is formed on one surface of a transparent cover layer 90 in a lattice shape.

[0141] As an example, a square or rectangular glass substrate having a certain thickness may be used for the transparent cover layer 90 . The size of the transparent cover layer 90 may roughly correspond to the size of the TFT substrate 20 .

[0142] The black matrix 74 forms a plurality of cells due to its configuration in a lattice shape, and each cell may be a sub-pixel region. Similarly, in operation S720, a color filter is formed in a predetermined cell among the plurality of cells of the black matrix 74.

[0143] For example, to form the first color filter 81, a red material is uniformly applied to the entire one surface of the transparent cover layer 90 formed with the black matrix 74. Then, only the area where red should remain is exposed by using a mask, and the red material is removed by development in the remaining areas.

[0144] Then, in order to form the second color filter 82, a green material is uniformly applied on the entire one surface of the transparent cover layer 90. Then, only the area where green should remain is exposed by using a mask, and the green material is removed in the remaining area by development.

[0145] Finally, to form the second transparent resin layer 83, a transparent resin material is uniformly coated on the entire one surface of the transparent cover layer 90. Then, only the area where the transparent resin should remain is exposed by using a mask, and the transparent resin material is removed by development in the remaining area.

[0146] As a method of applying the color filter material and the transparent resin material on the transparent cover layer 90, a slit method of uniformly applying the material on the entire surface using a printer nozzle, a spin method of spraying liquid in the center and then applying the liquid by a rotating plate, etc. can be applied.

[0147] When the first and second color filters 81 and 82 and the second transparent resin layer 83 are formed, a partition wall 70 having a lattice shape is formed on the upper surface of the black matrix in operation S730. Each unit formed by the partition wall 70 may be formed at a position corresponding to each unit formed by the above-mentioned black matrix 74. In this case, each unit formed by the partition wall 70 corresponds to a sub-pixel region.

[0148] According to an embodiment, a process of forming a planarization layer 75 covering the first color filter 81 and the second color filter 82 and the second transparent resin layer 83 may be performed so that the partition wall 70 may be laminated on the black matrix. The upper surface of the planarization layer 75 has a flatness to such an extent that the partition wall 70 may form a uniform height. The planarization layer 75 may be formed of a transparent material that does not affect the transmittance, reflectivity, and refractive index of light. According to an embodiment of the present disclosure, the planarization layer 75 may not be included in the display module 10, and the process of forming the planarization layer 75 may also be omitted.

[0149] After forming the partition wall 70 , in operation S740 , a color conversion material (quantum dot material) is applied to each cell by an inkjet printing method, and the first color conversion layer 71 and the second color conversion layer 72 are sequentially patterned.

[0150] As another method of forming first color conversion layer 71 and second color conversion layer 72, the color conversion layers may be formed by mixing a quantum dot material into a photoresist and performing coating, exposure, and development in a manner similar to the above-described color filter manufacturing process.

[0151] The first color conversion layer 71 may be composed of red quantum dots 71 a that may emit light in a red wavelength band, and the second color conversion layer 72 may be composed of green quantum dots 72 a that may emit light in a green wavelength band.

[0152] Each of the first color conversion layer 71 and the second color conversion layer 72 may include a plurality of foam particles for scattering light of a blue wavelength band emitted from the first micro LED 61 and the second micro LED 62 , respectively.

[0153] Here, according to one or more embodiments, a diameter of any one of the plurality of foam particles may be between 0.74 μm and 1.26 μm.

[0154] In addition, according to one or more embodiments, the plurality of foam particles may be foam particles of an inert gas. As an example, the plurality of foam particles may be implemented as a gas such as Ar, N 2 Etc. foam particles.

[0155] According to one or more embodiments, the volume fraction of the plurality of foam particles for each of the first color conversion layer 71 and the second color conversion layer 72 may be between 5.3% and 9%. For example, the volume occupied by the plurality of foam particles 71b in the total volume of the first color conversion layer 71 may be between 5.3% and 9%.

[0156] After patterning the first color conversion layer 71 and the second color conversion layer 72 to each cell, a transparent resin material is patterned to an empty cell where the first color conversion layer 71 and the second color conversion layer 72 are not formed by an inkjet printing method, and thus the first transparent resin layer 73 is formed.

[0157] Through the above-described process, the first portion of the upper plate constituting the display module 10 may be formed.

[0158] Fig. 9 is an exemplary diagram illustrating a method of manufacturing a first color conversion layer including a plurality of foam particles according to one or more embodiments of the present disclosure.

[0159] Reference Fig. 9, a plurality of red quantum dots 71a and a photocurable resin material are mixed inside a chamber 200 including an inert gas. For example, the following process may be performed: after a plurality of red quantum dots 71a are included in the photocurable resin material, the curing material including the plurality of red quantum dots 71a is placed inside a chamber including an inert gas, and then the curing material including the plurality of red quantum dots 71a is stirred. Thus, a plurality of foam particles 71b of the inert gas may be generated in the curing resin material. The inert gas may be a gas such as Ar, N 2 The above method is also applicable to the case of the second color conversion layer, and a plurality of foam particles 72b may be generated inside the cured resin material constituting the second color conversion layer.

[0160] Fig.10 is a flowchart showing a manufacturing process of a second portion of a display module according to one or more embodiments, and Fig.11 is a process diagram of a second portion of a display module according to one or more embodiments. Fig.11 In the figure, the entire second portion of the display module 10 is not shown, but a portion corresponding to one pixel is shown in an enlarged size. Here, the second portion is a portion including a plurality of self-luminous elements on the first substrate in the display module 10, and the second portion may be a portion constituting the lower surface or lower plate of the display module 10.

[0161] Reference Fig.10 and Fig.11 In operation S1010, an anisotropic conductive film 50 is laminated on the front surface of the TFT substrate 20. 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.

[0162] After the anisotropic conductive film 50 is attached to the TFT substrate 20, a plurality of micro LEDs are transferred to the TFT substrate 20 in operation S1020. The transfer process of the micro LEDs may be performed by a laser transfer method, a roll transfer method, a pick and place transfer method, etc. In this case, the first micro LED 61, the second micro LED 62, and the third micro LED 63 are respectively transferred from the epitaxial substrate to a relay substrate (or an interposer), and then transferred from each relay substrate to the TFT substrate 20 as a target substrate.

[0163] When the first micro LED 61, the second micro LED 62, and the third micro LED 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 micro LED 61, the second micro LED 62, and the third micro LED 63 are inserted into the inside of the anisotropic conductive film 50 to a predetermined depth by a thermal pressing process. Therefore, the first micro LED 61, the second micro LED 62, and the third micro LED 63 are physically fixed on the TFT substrate 20. In addition, the chip electrode of each micro LED 61, 62, 63 can be electrically connected to the corresponding substrate electrode pad through a plurality of conductive balls distributed inside the anisotropic conductive film 50.

[0164] The first micro LED 61, the second micro LED 62, and the third micro LED 63 may be blue micro LEDs emitting light in a blue wavelength band.

[0165] Then, in operation S1030 , an optical adhesive 65 for bonding the first portion to the second portion is applied on the front surface of the TFT substrate 20 .

[0166] The optical adhesive 65 is applied on the TFT substrate 20 so that the optical adhesive 65 can cover all of the plurality of micro LEDs 61, 62, 63. The optical adhesive 65 can be a UV curable silicone rubber (chemical name: dimethylsiloxane) having a property of curing after a certain time after exposure to UV.

[0167] Then, in operation S1040, the optical adhesive 65 is cured by irradiating UV onto the optical adhesive 65 during a predetermined time.

[0168] Through the above-described process, the second portion of the lower plate constituting the display module 10 may be formed.

[0169] Hereinafter, a process of manufacturing the display module 10 by bonding the first part and the second part to each other will be described.

[0170] Fig.12 is a diagram of a process of coupling a first portion and a second portion of a display module according to one or more embodiments.

[0171] exist Figure 6 In operation S630, the first color conversion layer corresponds to the first self-luminous element, and the second color conversion layer corresponds to the second self-luminous element, and the manufacturing method may further include: an operation of aligning the first substrate with the second substrate so that the transparent resin layer corresponds to the third self-luminous element.

[0172] For example, refer to Fig.12, after the second part is placed on a die, the first part is disposed above the second part at a specific interval.

[0173] Then, the first part 11 is flipped over to join the first part 11 and the second part 12 to each other, and the first part 11 is aligned in the joining position so that the first color conversion layer 71 and the second color conversion layer 72 of the first part correspond to the first micro-LED 61 and the second micro-LED 62 of the second part, and the first transparent resin layer 73 corresponds to the third micro-LED 63.

[0174] In this case, the first portion 11 and the second portion 12 may be disposed to remain parallel to each other with respect to the same plane.

[0175] After aligning the first part 11 and the second part 12 at the bonding position, the first part 11 and the second part 12 are abutted by a predetermined pressure and bonded to each other. In this case, the first part 11 and the second part 12 are attached to each other by the optical adhesive 65.

[0176] After the first portion 11 and the second portion 12 are bonded to each other, the optical adhesive 65 may be cured so that coupling between the first portion 11 and the second portion 12 may be ensured.

[0177] Through the above-described processes, the display module 10 according to one or more embodiments may be manufactured.

[0178] In the above, each of the various embodiments of the present disclosure is independently described, but each embodiment is not necessarily implemented separately, but the components and operations of each embodiment may be implemented in combination with the components and operations of at least one other embodiment.

[0179] In addition, although embodiments are shown and described above, the present disclosure is not limited to the above embodiments, and it is obvious that various modifications can be made by a person skilled in the art of the present disclosure without departing from the subject matter of the present disclosure as claimed in the attached claims and their equivalents. In addition, it is intended that these modifications should not be interpreted independently of the technical concept or prospect of the present disclosure.

Claims

1. A display module, comprising: substrate; as well as a plurality of pixels, on the substrate, Wherein, each of the plurality of pixels comprises: The first self-luminous element, the second self-luminous element and the third self-luminous element are configured to emit light of a first wavelength band respectively; a first color conversion layer configured to be disposed on the first self-luminous element and including a plurality of first quantum dots for absorbing the light of the first wavelength band emitted from the first self-luminous element and emitting light of a second wavelength band; and a second color conversion layer, configured to be disposed on the second self-luminous element and including a plurality of second quantum dots, for absorbing the light of the first wavelength band emitted from the second self-luminous element and emitting light of a third wavelength band, The first color conversion layer and the second color conversion layer include a plurality of foam particles, and the plurality of foam particles are configured to scatter light emitted from the first self-luminous element and light emitted from the second self-luminous element.

2. The display module according to claim 1, wherein: A diameter of each foam particle among the plurality of foam particles is between 0.74 μm and 1.26 μm.

3. The display module according to claim 1, wherein: The plurality of foam particles are foam particles of an inert gas.

4. The display module according to claim 1, wherein: A volume fraction of the plurality of foam particles for each of the first color conversion layer and the second color conversion layer is between 5.3% and 9%.

5. The display module according to claim 1, wherein: Each of the first color conversion layer and the second color conversion layer also includes a plurality of scattering particles.

6. The display module according to claim 5, wherein: A mass ratio of the plurality of first quantum dots to the plurality of scattering particles included in the first color conversion layer is between 1:0.04 and 1:0.14, and Wherein, a mass ratio of the plurality of second quantum dots to the plurality of scattering particles included in the second color conversion layer is between 1:0.04 and 1:0.

14.

7. The display module according to claim 1, wherein: The first self-luminous element, the second self-luminous element and the third self-luminous element are blue micro light emitting diodes.

8. The display module according to claim 7, wherein: The plurality of first quantum dots are configured to absorb light in a blue wavelength band and emit light in a red wavelength band, and The plurality of second quantum dots are configured to absorb light in a blue band and emit light in a green band.

9. The display module according to claim 1, further comprising: a first color filter on the first color conversion layer; as well as A second color filter is on the second color conversion layer.

10. The display module according to claim 9, further comprising: a first transparent resin layer, on the third self-luminous element; as well as a second transparent resin layer, on the first color conversion layer, The second transparent resin layer, the first color filter and the second color filter are on the same plane.

11. A method for manufacturing a display module, the method comprising: forming a first self-luminous element, a second self-luminous element and a third self-luminous element corresponding to a plurality of sub-pixels on the first substrate; forming a first color conversion layer and a second color conversion layer including a plurality of foam particles in regions corresponding to the first self-luminous element and the second self-luminous element among regions partitioned by a plurality of partitions formed on the second substrate; forming a transparent resin layer in a region corresponding to the third self-luminous element among the regions partitioned by the plurality of partitions; as well as bonding the first substrate and the second substrate to each other, bonding the plurality of color conversion layers to the first and second self-luminous elements, and bonding the transparent resin layer to the third self-luminous element, The first color conversion layer includes a plurality of first quantum dots, and the plurality of first quantum dots are configured to absorb light of a first wavelength band emitted from the first self-luminous element and emit light of a second wavelength band. The second color conversion layer includes a plurality of second quantum dots, and the plurality of second quantum dots are configured to absorb the light of the first wavelength band emitted from the second self-luminous element and emit light of a third wavelength band, and The light emitted from the first self-luminous element and the light emitted from the second self-luminous element are scattered by the plurality of foam particles included in the first color conversion layer and the second color conversion layer.

12. The manufacturing method according to claim 11, further comprising: forming a plurality of black matrices at predetermined intervals on the second substrate; forming a color filter between the plurality of black matrices formed on the second substrate; as well as A partition is formed on each of the plurality of black matrices to correspond to the plurality of sub-pixels.

13. The manufacturing method according to claim 11, further comprising: The first substrate and the second substrate are bonded to each other so 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.

14. The manufacturing method according to claim 11, wherein: A diameter of each foam particle among the plurality of foam particles is between 0.74 μm and 1.26 μm.

15. The manufacturing method according to claim 11, wherein: The plurality of foam particles are foam particles of an inert gas.

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