Display module and method of manufacturing the same

Abstract

A method for manufacturing a display module, comprising: forming a driving circuit layer on a substrate, the driving circuit layer comprising a plurality of driving circuits and a plurality of electrode pads electrically connected to the plurality of driving circuits; forming an adhesive layer on the driving circuit layer; transferring each of a plurality of light emitting diodes (LEDs) to a corresponding area of ​​the adhesive layer corresponding to a corresponding electrode pad among the plurality of electrode pads; and forming a black matrix layer on the adhesive layer located between the plurality of LEDs.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a display module and a method for manufacturing the same, and more particularly, to a display module for micro LEDs and a method for manufacturing the same. Background Art

[0002] A light emitting diode (LED) is a semiconductor element that emits light when voltage is applied, and is widely used not only as a general lighting device but also as a light source for a display device for displaying images.

[0003] Recently, a display device (or display panel, display module, etc.) using micro-LEDs (μ-LEDs or micro light-emitting diodes) as light sources in units of pixels or sub-pixels is being developed. Here, micro-LEDs may refer to semiconductor light-emitting elements having a size of between 1 and 100 micrometers (μm) in width, length, and height, respectively.

[0004] Here, micro-LED display panels provide better contrast, response time and energy efficiency than liquid crystal display (LCD) panels that require a separate backlight unit. In addition, because micro-LED display panels use inorganic substances, they have the advantages of less screen burn-in, longer life, higher luminous efficiency and higher brightness compared to organic LEDs (OLEDs).

[0005] Generally speaking, in a method of manufacturing a display module using a micro LED as a light source, the micro LED is transferred to a substrate through a transfer process, and the electrode pads of the micro LED are electrically connected to the electrode pads of the substrate through connection processes such as welding and thermosetting. Then, a black matrix (BM) layer is formed in a non-luminous area by printing (e.g., inkjet / screen printing, etc.) or exposure / development. Here, BM is a substance that absorbs light and has a black color, and it can be used to improve the contrast of the display by reducing the reflected light of external light.

[0006] However, in the case of such a general BM formation method, a BM opening area where no BM is formed may be formed around the micro-LED due to various factors, such as the size tolerance of the substrate itself, the tolerance of the size or connection position of the micro-LED, the distance between the micro-LEDs, the alignment tolerance between the substrate and the BM in the case of printing or exposure / development, the size tolerance of the BM itself in the case of combining a patterned BM component with the substrate, the tolerance generated during the BM formation process (such as alignment tolerance), etc. The BM opening area has a problem in that since it exposes a portion of the substrate (for example, the electrode pad of the substrate), the contrast is reduced and the overall expression of black is reduced. In addition, there is a problem in that in the case of improper alignment, a BM may be formed on the micro-LED, and such a BM formed on the micro-LED covers the light-emitting surface of the micro-LED, which leads to a reduction in luminous efficiency. Summary of the invention

[0007] Technical Solution

[0008] According to one or more embodiments, a method for manufacturing a display module including a plurality of pixels is provided. The method includes: forming a driving circuit layer on a substrate, the driving circuit layer including a plurality of driving circuits and a plurality of electrode pads electrically connected to the plurality of driving circuits; forming an adhesive layer on the driving circuit layer; transferring each of a plurality of light emitting diodes (LEDs) to a corresponding region of the adhesive layer corresponding to a corresponding electrode pad in a plurality of electrode pads; and forming a black matrix layer on the adhesive layer located between a plurality of LEDs. The attachment includes: attaching a black matrix forming layer attached to a film to a plurality of LEDs and to a portion of the adhesive layer formed between a plurality of LEDs; and removing a first portion of the black matrix forming layer attached to a plurality of LEDs together with the film, so that a second portion of the black matrix forming layer remains between the plurality of LEDs as a black matrix layer. Each of the plurality of pixels includes a plurality of sub-pixels, and each of the plurality of electrode pads includes a first region for bonding a first LED corresponding to a sub-pixel in the plurality of sub-pixels and a second region for bonding a second LED corresponding to the sub-pixel based on a defect in the first LED.

[0009] According to an embodiment, the attaching includes attaching the black matrix forming layer to portions of the adhesive layer formed between the plurality of LEDs and to the plurality of LEDs through a thermal compression process.

[0010] According to an embodiment, the adhesive layer includes an anisotropic conductive film (ACF) including a conductive material, and the attaching further includes electrically connecting each of the plurality of LEDs to the plurality of electrode pads through the conductive material.

[0011] According to an embodiment, the adhesive layer includes a non-conductive film containing flux, and the attachment also includes: melting a bump, the bump is applied on an electrode of each of a plurality of LEDs or is applied on a plurality of electrode pads; and electrically connecting each of the plurality of LEDs to the plurality of electrode pads through the bump when the bump is in a molten form, and the flux is configured to remove an oxide film generated when the bump is melted.

[0012] According to the embodiment, the adhesive force between the adhesive layer and the black matrix forming layer is stronger than the adhesive force between the film and the black matrix forming layer.

[0013] According to an embodiment, the removal includes: after removing the film from the black matrix forming layer, attaching a tape to the black matrix forming layer, and removing the remaining portion of the black matrix forming layer attached to the multiple LEDs together with the tape from the multiple LEDs, so that a second portion of the black matrix forming layer remains between the multiple LEDs as a black matrix layer, wherein the bonding force between the tape and the black matrix forming layer is weaker than the bonding force between the black matrix forming layer and the adhesive layer.

[0014] According to an embodiment, the second LED is configured to emit light of the same color as the first LED.

[0015] According to an embodiment, a size of each of the plurality of electrode pads is larger than a size of the first LED, and the first region and the second region are electrically connected.

[0016] According to an embodiment, each of the plurality of LEDs is a micro LED of a flip chip structure in which an electrode is formed at a lower portion of the flip chip structure.

[0017] According to one or more embodiments, a display module is provided. The display module includes: a substrate; a driving circuit layer formed on the substrate, the driving circuit layer including a plurality of driving circuits and a plurality of electrode pads electrically connected to the plurality of driving circuits; an adhesive layer formed on the driving circuit layer; a plurality of light emitting diodes (LEDs), each of the plurality of LEDs being formed on a corresponding region of the adhesive layer corresponding to a corresponding electrode pad among the plurality of electrode pads; and a black matrix layer formed on the adhesive layer between the plurality of LEDs, wherein the display module is configured to include a plurality of pixels, the plurality of pixels including a plurality of sub-pixels, and each of the plurality of electrode pads including a first region for bonding a first LED corresponding to a sub-pixel among the plurality of sub-pixels and a second region for bonding a second LED corresponding to the sub-pixel based on the first LED being defective.

[0018] According to an embodiment, a black matrix layer is formed on an adhesive layer located between a plurality of LEDs in the following manner: a black matrix forming layer attached to a film is attached to a portion of the adhesive layer formed between the plurality of LEDs and to the plurality of LEDs through a heat pressing process; and a first portion of the black matrix forming layer attached to the plurality of LEDs is removed from the plurality of LEDs together with the film, so that a second portion of the black matrix forming layer remains between the plurality of LEDs as a black matrix layer.

[0019] According to an embodiment, a plurality of LEDs are electrically connected to a plurality of electrode pads through a thermal compression process.

[0020] According to an embodiment, the adhesive layer includes an anisotropic conductive film (ACF) including a conductive material, and the plurality of LEDs are electrically connected to the plurality of electrode pads through the conductive material via a thermal compression process.

[0021] According to an embodiment, the adhesive layer includes a non-conductive film including a flux, a bump is applied on an electrode of each of a plurality of LEDs or on a plurality of electrode pads, the bump is melted by a thermal pressing process, a plurality of LEDs are electrically connected to the plurality of electrode pads through the bump when the bump is in a molten form, and the flux is configured to remove an oxide film generated when the bump is melted.

[0022] According to the embodiment, the adhesive force between the adhesive layer and the black matrix forming layer is stronger than the adhesive force between the film and the black matrix forming layer.

[0023] According to an embodiment, the second LED is configured to emit light of the same color as the first LED.

[0024] According to an embodiment, a size of each of the plurality of electrode pads is larger than a size of the first LED, and the first region and the second region are electrically connected.

[0025] According to an embodiment, each of the plurality of LEDs is a micro LED of a flip chip structure in which an electrode is formed at a lower portion of the flip chip structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram for illustrating a display module according to an embodiment of the present disclosure;

[0027] Figure 2A is a schematic diagram for illustrating a display module according to an embodiment of the present disclosure;

[0028] Figure 2B For illustrating an embodiment of the present disclosure Figure 2A A cross-sectional view of a display module;

[0029] Figure 2C is a cross-sectional view for illustrating an LED according to an embodiment of the present disclosure;

[0030] Figure 3A is a cross-sectional view for illustrating the connection of a display module according to an embodiment of the present disclosure;

[0031] Figure 3B is a cross-sectional view for illustrating the connection of a display module according to an embodiment of the present disclosure;

[0032] Figure 4A is a schematic diagram for illustrating a display module for compensating defective pixels according to an embodiment of the present disclosure;

[0033] Figure 4B is a schematic diagram for illustrating a display module for compensating defective pixels according to an embodiment of the present disclosure;

[0034] Figure 5Ais a cross-sectional view for illustrating a display module for compensating defective pixels according to an embodiment of the present disclosure;

[0035] Figure 5B is a cross-sectional view for illustrating a display module for compensating defective pixels according to an embodiment of the present disclosure;

[0036] Figure 6 is a flow chart for illustrating a method for manufacturing a display panel according to an embodiment of the present disclosure;

[0037] Fig. 7A is a schematic diagram for illustrating a driving circuit layer according to an embodiment of the present disclosure;

[0038] Figure 7B is a cross-sectional view for illustrating a driving circuit layer according to an embodiment of the present disclosure;

[0039] Figure 7C is a cross-sectional view for illustrating a driving circuit layer according to an embodiment of the present disclosure;

[0040] Fig. 8A is a schematic diagram for illustrating a method for forming an adhesive layer according to an embodiment of the present disclosure;

[0041] Figure 8B is a cross-sectional view for illustrating a method of forming an adhesive layer according to an embodiment of the present disclosure;

[0042] Figure 8C is a cross-sectional view for illustrating a method of forming an adhesive layer according to an embodiment of the present disclosure;

[0043] Fig.8D is a cross-sectional view for illustrating a method of forming an adhesive layer according to an embodiment of the present disclosure;

[0044] Fig. 9A is a schematic diagram for illustrating a method of transferring an LED according to an embodiment of the present disclosure;

[0045] Fig. 9B is a cross-sectional view for illustrating a method of transferring an LED according to an embodiment of the present disclosure;

[0046] Fig. 9C is a cross-sectional view for illustrating a method of transferring an LED according to an embodiment of the present disclosure;

[0047] Fig.9D is a cross-sectional view for illustrating a method of transferring an LED according to an embodiment of the present disclosure;

[0048] Fig. 10A is a cross-sectional view for illustrating a method of attaching a film according to an embodiment of the present disclosure;

[0049] Fig. 10B is a cross-sectional view for illustrating a method of attaching a film according to an embodiment of the present disclosure;

[0050] Fig. 10C is a cross-sectional view for illustrating a method of attaching a film according to an embodiment of the present disclosure;

[0051] Fig.11A is a cross-sectional view for illustrating a method of forming a black matrix layer according to an embodiment of the present disclosure;

[0052] Fig. 11B is a cross-sectional view for illustrating a method of forming a black matrix layer according to an embodiment of the present disclosure;

[0053] Fig. 12A is a schematic diagram for illustrating a display module manufactured according to an embodiment of the present disclosure;

[0054] Fig. 12B is a cross-sectional view for illustrating a display module manufactured according to an embodiment of the present disclosure;

[0055] Fig. 12C is a cross-sectional view for illustrating a display module manufactured according to an embodiment of the present disclosure;

[0056] Fig.13A is a cross-sectional view for illustrating a method of forming a black matrix layer according to an embodiment of the present disclosure;

[0057] Fig. 13B is a cross-sectional view for illustrating a method of forming a black matrix layer according to an embodiment of the present disclosure; and

[0058] Fig. 13C is a cross-sectional view for illustrating a method of forming a black matrix layer according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0059] According to an aspect of an embodiment of the present disclosure, a display module that enhances black expression is provided, and a method for manufacturing the display module is provided.

[0060] When describing various aspects of the present disclosure, if it is determined that the detailed description of the relevant known functions or components may unnecessarily confuse the subject matter of the present disclosure, the detailed description will be omitted. In addition, the following embodiments may be modified in various different forms, and the scope of the technical ideas of the present disclosure is not limited to the following embodiments. Instead, these embodiments are provided to make the present disclosure more complete and complete, and to fully convey the technical ideas of the present disclosure to those skilled in the art.

[0061] In addition, the embodiments of the present disclosure are not intended to limit the technology described in the present disclosure to specific embodiments, but should be interpreted as including various modifications, equivalents and / or substitutions of the embodiments of the present disclosure. In addition, with respect to the detailed description of the drawings, similar components may be represented by similar reference numerals.

[0062] In addition, the expressions "first", "second", etc. used in the present disclosure may be used to describe various elements, regardless of any order and / or degree of importance. Moreover, such expressions are only used to distinguish one element from another element and are not intended to limit these elements.

[0063] In addition, in the present disclosure, the expression "A or B", "at least one of A and / or B", or "one or more of A and / or B", etc. may include all possible combinations of the listed items. For example, "A or B", "at least one of A and B", or "at least one of A or B" may refer to all of the following situations: (1) including at least one A, (2) including at least one B, or (3) including at least one A and at least one B.

[0064] In addition, in the present disclosure, singular expressions include plural expressions as long as they do not have obviously different meanings in the context. In addition, in the present disclosure, terms such as "include", "comprising", etc. should be understood to indicate the presence of the features, quantities, steps, operations, elements, components or combinations thereof described in the specification, but should not be understood to exclude in advance the possibility of the presence or addition of one or more other features, quantities, steps, operations, elements, components or combinations thereof.

[0065] In addition, the description in the present disclosure that an element (e.g., a first element) is "(operably or communicatively) coupled to / coupled to" or "connected to" another element (e.g., a second element) should be interpreted as including the case where the one element is directly coupled to the other element, and the case where the one element is coupled to the other element through another element (e.g., a third element). Conversely, the description that an element (e.g., a first element) is "directly coupled" or "directly connected to" another element (e.g., a second element) may be interpreted to mean that there is no another element (e.g., a third element) between the one element and the other element.

[0066] In addition, the expression "configured to" used in the present disclosure may be used interchangeably with other expressions such as "suitable for", "capable of", "designed to", "adapted to", "manufactured to", and "capable of", as appropriate. At the same time, the term "configured to" does not necessarily mean that the device is "specially designed to" in terms of hardware. On the contrary, in some cases, the expression "a device configured to..." may mean that the device is "capable of" performing operations together with another device or component. For example, the phrase "a processor configured to perform A, B, and C" may refer to a dedicated processor (e.g., an embedded processor) for performing the corresponding operations or a general-purpose processor (e.g., a CPU or an application processor) that can perform the corresponding operations by executing one or more software programs stored in a memory device.

[0067] Hereinafter, various non-limiting example embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0068] Figure 1 is a schematic diagram for illustrating a display module according to an embodiment of the present disclosure.

[0069] Reference Figure 1 , the display module 1 may include a plurality of pixels (eg, a first pixel 100 - 1 and a second pixel 100 - 2 ).

[0070] The display module 1 may display an image through a plurality of pixels (e.g., a first pixel 100-1 and a second pixel 100-2). Here, the first pixel 100-1 is the smallest unit constituting an image and may refer to a point having an independent color or brightness. Here, the first pixel 100-1 may include a combination of a plurality of sub-pixels (e.g., sub-pixels such as red, green, blue, etc.) or be composed of a combination of a plurality of sub-pixels.

[0071] A plurality of pixels (e.g., a first pixel 100-1 and a second pixel 100-2) may be arranged to be separated from each other at a predetermined interval therebetween. In addition, a plurality of pixels (e.g., a first pixel 100-1 and a second pixel 100-2) may be arranged in a matrix form. Here, the matrix form may refer to a form having the same number of rows and columns as each other (e.g., in the case of M=N, 3×3 arrangement, 5×5 arrangement, etc., and here, M and N are natural numbers) or a form having different numbers of rows and columns as each other (e.g., in the case of M≠N, 3×2 arrangement, 5×4 arrangement, etc., and here, M and N are natural numbers).

[0072] Meanwhile, a plurality of pixels (e.g., the first pixel 100-1 and the second pixel 100-2) may have the same structure and function as each other. Therefore, unless there are special circumstances, the description of the first pixel 100-1 may be applied to other pixels (e.g., the second pixel 100-2) in the plurality of pixels in the same manner.

[0073] Meanwhile, as an example different from the above, the display module 1 is one of the plurality of display modules and can be connected to another display module and display an image. To this end, the plurality of display modules can be arranged in the above-mentioned matrix form.

[0074] Hereinafter, a display module according to an embodiment of the present disclosure will be described in more detail with reference to the accompanying drawings.

[0075] Figure 2A is a schematic diagram for illustrating a display module according to an embodiment of the present disclosure, and Figure 2B for relative to Figure 2A Cross-sectional view along line A1-A2.

[0076] Reference Figure 2A and Figure 2B The display module 1 may include a substrate 10 , a driving circuit layer 20 , an adhesive layer 30 , a plurality of light emitting diodes (LEDs) 50 (eg, a red LED 50R, a green LED 50G, a blue LED 50B), and a black matrix layer 60 .

[0077] The substrate 10 may be implemented in the form of a plate having a thickness smaller than the width and length. For example, the substrate 10 may have various thicknesses, such as from tens of micrometers to tens of millimeters.

[0078] In addition, the substrate 10 may perform functions of supporting and protecting various electronic components formed on the substrate 10, such as the driving circuit layer 20, the plurality of LEDs 50, etc., and may be implemented as a material having a transparent property or a rigid or flexible property. For example, the substrate 10 may be implemented as various materials, such as glass, polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), etc.

[0079] The driving circuit layer 20 may be formed on the substrate 10. In addition, the driving circuit layer 20 may include a plurality of driving circuits 21 and a plurality of electrode pads 22 (eg, electrode pads 22R, electrode pads 22G, electrode pads 22B).

[0080] The driving circuit 21 can send a driving signal to the LED 50 to make the LED 50 emit light. Specifically, the driving circuit 21 can control the on / off state of the switching element (not shown), and send a driving signal to the LED 50 when the switching element is turned on, thereby controlling the LED 50 to emit light. Here, the switching element can be implemented as, for example, a thin film transistor (TFT, not shown). Various circuits included in the driving circuit 21 can be implemented in the form of, for example, a printed circuit board (PCB) or the like.

[0081] Here, the TFT (or backplane) is not limited to a specific structure or type. That is, the TFT can be implemented as a low temperature polysilicon (LTPS) TFT, an oxide TFT, a polysilicon TFT, an amorphous silicon (a-silicon) TFT, an organic TFT, a graphene TFT, etc. In addition, the TFT can be implemented as various types, such as a P-type (or N-type) MOSFET formed in a Si wafer CMOS process, etc.

[0082] To this end, the driving circuit 21 may be electrically connected to the LED 50 through the electrode pad 22. Here, the electrode pad 22 is electrically connected to the driving circuit 21, and may be implemented as various materials having high conductivity, such as Cu, Au, Ag, indium tin oxide (ITO), etc. In addition, the electrode pad 22 is divided into an anode and a cathode according to polarity, and the anode and the cathode may be electrically separated (or insulated) from each other.

[0083] Each of the plurality of electrode pads 22 (e.g., electrode pad 22R, electrode pad 22G, electrode pad 22B) may include one of a first region 111, 121, 131 for engaging a first LED corresponding to one of a plurality of sub-pixels (e.g., one of the red, green, and blue sub-pixels) and a second region 112, 122, 132 for engaging a second LED corresponding to the sub-pixel when the first LED is defective.

[0084] The adhesive layer 30 may be formed on the driving circuit layer 20. The adhesive layer 30 may attach the plurality of LEDs 50 transferred onto the driving circuit layer 20 to the driving circuit layer 20. To this end, the adhesive layer 30 may be implemented as various materials having adhesiveness.

[0085] The adhesive layer 30 according to the embodiment of the present disclosure includes an anisotropic conductive film (ACF) 31 (see, for example, Figure 3A , Figure 5A , Fig. 9B ), and the ACF 31 may include a conductive material 32. In this case, the plurality of LEDs 50 may be electrically connected to the plurality of electrode pads 22 through the conductive material 32 via a thermal compression process.

[0086] The adhesive layer 30 according to the embodiment of the present disclosure includes a non-conductive film 35 (see Figure 3B , Figure 5B , Fig.8D , Fig.9D , Fig. 11B) and the non-conductive film 35 may include flux (not shown). In this case, the bump applied to the electrode of each of the plurality of LEDs 50 or the bump applied to the plurality of electrode pads 22 is melted by a thermal press process, and the plurality of LEDs 50 may be electrically connected to the plurality of electrode pads 22 through the melted bump. Here, the oxide film generated when the bump is melted may be removed by the flux.

[0087] The plurality of LEDs 50 may be electrically connected to the plurality of electrode pads 22 through a thermal compression process.

[0088] Specifically, before the adhesive layer 30 is cured by the heat press process, the adhesive layer 30 may have fluidity (or flowability). After the adhesive layer 30 is cured by the heat press process, the fluidity of the adhesive layer 30 may be reduced and the adhesiveness of the adhesive layer 30 may be improved.

[0089] For example, when the adhesive layer 30 is pressurized along the direction of the substrate 10 to the multiple LEDs 50 transferred to the driving circuit layer 20 by the hot pressing process, due to the fluidity of the adhesive layer 30, the multiple LEDs 50 push the adhesive layer 30 located at the lower part to the surrounding part, and therefore, the following form can be constituted: some LEDs among the multiple LEDs 50 are buried while other LEDs among the multiple LEDs 50 protrude based on the longitudinal direction of the adhesive layer 30. Here, the multiple LEDs 50 can be pressurized to be electrically connected to the multiple driving circuits 21 through the multiple electrode pads 22. Thereafter, when the adhesive layer 30 is cured, the multiple LEDs 50 can be fixed on the driving circuits 21 while being electrically connected to the multiple driving circuits 21 through the multiple electrode pads 22. This will be referred to later. Figure 3A and Figure 3B This is explained in more detail.

[0090] Each of the plurality of LEDs 50 may emit light of a specific color. Here, each of the plurality of LEDs 50 may be a micro LED having a size of width, length, and height greater than or equal to 1 micrometer (μm) and less than or equal to 100 micrometers.

[0091] Specifically, each of the plurality of LEDs 50 may emit light of one of three primary colors of light (eg, red, green, and blue) and form a sub-pixel. Here, the plurality of sub-pixels may refer to subordinate units constituting the pixel 100.

[0092] For example, the red LED 50R can emit red light and form a red sub-pixel, the green LED 50G can emit green light and form a green sub-pixel, and the blue LED 50B can emit blue light and form a blue sub-pixel. In this case, by combining the light emitted from the red LED 50R, the green LED 50G and the blue LED 50B, a pixel 100 showing a specific color and brightness can be formed.

[0093] To this end, a plurality of LEDs 50 may be formed on regions of the adhesive layer 30 corresponding to the plurality of electrode pads 22 .

[0094] Specifically, the plurality of LEDs 50 may be formed in a region electrically connected to the plurality of electrode pads 22. For example, the plurality of LEDs 50 may be formed in a region where the plurality of LEDs 50 and the plurality of electrode pads 22 of the driving circuit layer 20 directly contact each other or indirectly contact each other through a conductive material.

[0095] Here, the region in which the plurality of LEDs 50 are electrically connected to the plurality of electrode pads 22 of the driving circuit layer 20 may be the first region 111 , 121 , 131 or the second region 112 , 122 , 132 present on the plurality of electrode pads 22 .

[0096] Reference Figure 2C , each LED 50 may include a first semiconductor layer 51 , a second semiconductor layer 53 , a light emitting layer 52 , and an electrode 55 .

[0097] One of the first semiconductor layer 51 and the second semiconductor layer 53 may be configured as an n-type semiconductor, and the other may be configured as a p-type semiconductor. Specifically, the first semiconductor layer 51 and the second semiconductor layer 53 may be configured as various n-type or p-type semiconductors having a band gap energy (eV) corresponding to a specific wavelength in the spectrum. For example, the first semiconductor layer 51 and the second semiconductor layer 53 may include layers such as GaAs, GaInN, AlInGaP, AlInGaN, GaP, GaN, SiC, sapphire (Al 2 O 3 ) and the like, and depending on the compound and the composition ratio, light having red, green and blue wavelengths can be emitted from the active layer, and red, green and blue sub-pixels can be realized.

[0098] The light emitting layer (or active layer) 52 may refer to a layer formed between the first semiconductor layer 51 and the second semiconductor layer 53 when the first semiconductor layer 51 and the second semiconductor layer 53 are bonded. In addition, the light emitting layer 52 may include at least one barrier layer having a single quantum well structure or a multiple quantum well (MQW) structure.

[0099] The electrode 55 of each LED 50 may include a first electrode 56 and a second electrode 57 electrically connected to each of the anode and the cathode of one of the electrode pads 22 of one of the driving circuits 21. Here, the first electrode 56 and the second electrode 57 may be one of an n-type electrode and a p-type electrode according to the type (n-type or p-type) of the first semiconductor layer 51 and the second semiconductor layer 53.

[0100] Meanwhile, each of the plurality of LEDs 50 may be a micro LED of a flip chip structure in which an electrode 55 is formed at a lower portion. Here, the flip chip structure may refer to a micro LED of a flip chip structure. Figure 2C A structure in which the first electrode 56 and the second electrode 57 are formed on the lower surface of one of the LEDs 50. That is, the electrode 55 of the micro LED of the flip chip structure can be formed on the lower surface of the micro LED so as to be opposite to one of the electrode pads 22 of one of the driving circuits 21.

[0101] However, this is merely an example, and the display module may be implemented to be modified into various structures, such as a vertical structure in which one of the first electrode 56 and the second electrode 57 is formed on each of the upper and lower surfaces of one of the LEDs 50, a structure in which both the first electrode 56 and the second electrode 57 are formed on the upper surface of the LED 50, and the like.

[0102] Refer again Figure 2A and Figure 2B , the black matrix layer 60 may be formed on the adhesive layer 30 formed between the plurality of LEDs 50 .

[0103] The black matrix layer 60 may be formed in the remaining regions of the adhesive layer 30 except for the region where the plurality of LEDs 50 are bonded. That is, the black matrix layer 60 may cover the region on the adhesive layer 30 to which the plurality of LEDs 50 are not bonded. Here, the black matrix layer 60 has a property of absorbing light and presenting black, and it may be implemented as various materials, such as a polymer, a metal oxide, etc. In addition, the black matrix layer 60 may include a material having a high resistance property.

[0104] As the film 80 (see Fig. 10A ) of a black matrix layer 70 (eg, a black matrix forming layer) (see Fig. 10A ) is attached to the region (or referred to as “gap region”) of the adhesive layer 30 formed between the plurality of LEDs 50, and the black matrix layers 71, 72 (eg, black matrix forming layers) attached to the plurality of LEDs 50 (see Fig.11A and Fig. 12B) is removed together with the film 80, and a black matrix layer 60 may be formed on the adhesive layer 30 between the plurality of LEDs 50. Here, the adhesive force between the adhesive layer 30 and the black matrix layer 60 may be stronger than the adhesive force between the film 80 and the black matrix layer 60. FIG. 10A to FIG. 12C This is explained in detail.

[0105] The display module 1 according to various embodiments of the present disclosure described above can overcome most of the problems caused by the general method of forming a black matrix.

[0106] Specifically, the display module 1 according to the embodiment of the present disclosure does not use the printing and exposure / development process of liquid such as ink. Therefore, there is no need to manage tolerances, such as alignment tolerances required for the printing and exposure / development processes, tolerances of substrate materials, tolerances of connection positions of LEDs, tolerances in the printing process, tolerances in the exposure / development process, tolerances of black matrix materials, etc., and the process can be simplified.

[0107] Furthermore, since no liquid is used, the black matrix layer 60 is not formed on the plurality of LEDs 50 , and thus, a defect that light emitted from the plurality of LEDs 50 is blocked by the black matrix layer 60 can be prevented.

[0108] Furthermore, since the black matrix layer 60 is formed by forming the adhesive layer 30 in the entire region of the driving circuit layer 20, attaching the plurality of LEDs 50 to the adhesive layer 30, and utilizing the adhesive force of the exposed portion of the adhesive layer 30, it is possible to minimize the generation of a BM opening region in which a black matrix is ​​not formed between the plurality of LEDs 50. That is, by forming the black matrix layer 60 without tolerance in all regions except the region where the LEDs 50 are mounted, it is possible to maximize the region in which the black matrix layer 60 is formed, and thus, the black expression of the display can be maximized, and the contrast of the display can be improved.

[0109] Further, in the display module and the manufacturing method thereof according to the embodiment of the present disclosure, the LED and the electrode pads of the driving circuit are electrically connected at the same time when the BM is formed, and thus, there are effects of simplifying the process and reducing the cost.

[0110] Figure 3A and Figure 3B is a cross-sectional view for illustrating a connection method of a display module according to an embodiment of the present disclosure.

[0111] The plurality of driving circuits 21 and the plurality of LEDs 50 included in the display module 1 according to the embodiment of the present disclosure may be electrically connected (or bonded) to each other through various methods.

[0112] As an example, see Figure 3A, the adhesive layer 30 may include an anisotropic conductive film (ACF) 31 , and the ACF 31 may include a conductive material 32 .

[0113] Here, ACF 31 may refer to an adhesive film in which conductive material 32 is arranged as dispersed. For example, ACF 31 may be implemented as a normal ACF in which conductive material 32 inside ACF 31 is randomly distributed, or an aligned ACF in which conductive material 32 inside ACF 31 is regularly arranged at specific intervals. The adhesive film may be implemented as various resins having adhesiveness.

[0114] Here, the conductive material 32 may be implemented in the form of conductive particles or conductive balls having conductivity. In addition, the conductive material 32 may be implemented in various ways, such as in the form of plastic on which conductive particles are coated. For example, the conductive material 32 may be implemented as various materials having conductivity, such as Au, Cu, Ni, etc. Meanwhile, the form of the conductive material 32 may be changed by heating or pressurizing.

[0115] Meanwhile, the size and thickness of the ACF 31 , the size and arrangement of the conductive material 32 , and the like may be implemented to be variously modified according to the size and arrangement of the LED 50 , and the like.

[0116] In this case, the plurality of LEDs 50 may be electrically connected to the plurality of electrode pads 22 through the conductive material 32 via a thermal compression process. For example, the electrode 55R formed at the lower portion of the red LED 50R may be electrically connected to the electrode pad 22R of one of the drive circuits 21 through the conductive material 32. In addition, the description of the red LED 50R may be applied in the same manner to the green LED 50G and the blue LED 50B. Figure 3A , each electrode pad 22 may include a first electrode pad 22 - 1 and a second electrode pad 22 - 2 .

[0117] As an example different from the above, refer to Figure 3B , the adhesive layer 30 may include a non-conductive film 35, and the non-conductive film 35 may include flux. Here, the non-conductive film 35 may be implemented as a thermosetting film that can be bonded by an underfill method when the bump 40 is soldered.

[0118] In this case, the bumps applied on the electrodes of each of the plurality of LEDs 50 or the bumps applied on the plurality of electrode pads 22 are melted by a thermal pressing process, and the plurality of LEDs 50 may be electrically connected to the plurality of electrode pads 22 through the bumps 40 when the bumps 40 are in a melted form.

[0119] For example, the electrode 55R formed at the lower portion of the red LED 50R may be electrically connected to the electrode pad 22R of one of the driving circuits 21 through the bump 40. Furthermore, the description of the red LED 50R may be applied in the same manner to the green LED 50G and the blue LED 50B.

[0120] Here, the flux can remove an oxide film generated when the bump 40 is melted. Specifically, when the bump 40 is melted (or soldered), the flux can remove contaminants or oxide films on the surface of the bump 40. To this end, the main component of the flux may be, for example, rosin, and the flux may include or consist of a material containing a small amount of a halogen activator (e.g., chlorine, fluorine, bromine, etc.).

[0121] Meanwhile, the bump 40 may be applied to each electrode 55 of the LED 50 or the electrode pad 22 of the driving circuit 21 by screen printing or the like, so that the bump 40 is located between each electrode 55 of the LED 50 and the electrode pad 22 of the driving circuit 21. Thereafter, as the temperature is raised to a temperature higher than or equal to the melting point of the bump by the thermal pressing process, the bump melts, and when the temperature drops later, the solidified bump is bonded between each electrode 55 of the LED 50 and the electrode pad 22 of the driving circuit 21, and the LED 50 and the driving circuit 21 may be electrically connected to each other.

[0122] To this end, the bump 40 may be implemented as conductive powder or the like, and may be implemented as various materials such as, for example, bonded Au—In, bonded Au—Sn, bonded Cu pillar / SnAg bump, bonded Ni pillar / SnAg bump, or the like.

[0123] Meanwhile, the display module 1 according to the embodiment of the present disclosure may have an electrode structure for compensating a defective pixel in the event of a defective pixel. FIG. 4A to FIG. 5B Provide explanation. Figure 5A and Figure 5B yes Figure 4A A cross-sectional view of the display module taken along line B1 - B2 is shown. Figure 5A A case where the adhesive layer 30 according to an embodiment of the present disclosure is an ACF 31 and is connected by a conductive material 32 is shown, and Figure 5B A case is shown in which the adhesive layer 30 according to an embodiment of the present disclosure is a non-conductive film 35 and is connected by a bump 40 .

[0124] Reference FIG. 4A to FIG. 5B, each of the plurality of electrode pads 22 (for example, including electrode pad 22R-1 and electrode pad 22R-2) may include one of first regions 111-1, 111-2, 121-1, 121-2, 131-1, 131-2 for bonding a first LED corresponding to one of the plurality of sub-pixels (one of the red, green, and blue sub-pixels) and one of second regions 112-1, 112-2, 122-1, 122-2, 132-1, 132-2 for bonding a second LED corresponding to the sub-pixel when the first LED is defective.

[0125] Meanwhile, the first regions 111-1, 111-2, 121-1, 121-2, 131-1, 131-2 are used to divide the display module in units of pixels, and except for special cases, the first regions 111-1, 111-2, 121-1, 121-2, 131-1, 131-2 have the same structure and function as each other. Similarly, except for special cases, the second regions 112-1, 112-2, 122-1, 122-2, 132-1, 132-2 may also have the same structure and function as each other.

[0126] Here, the second LED may be an LED emitting light of the same color as the first LED. For example, the first LED and the second LED may be LEDs emitting light of the same color (eg, one of red, green, and blue) corresponding to the sub-pixel.

[0127] Reference Figure 4A , Figure 5A and Figure 5B The display module 1 may include a substrate 10, a driving circuit layer 20 (as an example, refer to Figure 2B ), adhesive layer 30 (as an example, refer to Figure 2B ), multiple first LEDs (for example, red LED 50R-1, green LED 50G-1, blue LED 50B-1) bonded to the first area 111-1, 121-1, 131-1 of the first pixel 100-1 on the adhesive layer 30, multiple first LEDs (for example, red LED 50R-2, green LED 50G-2, blue LED 50B-2) bonded to the first area 111-2, 121-2, 131-2 of the second pixel 100-2 on the adhesive layer 30, and a black matrix layer 60.

[0128] The plurality of first LEDs (e.g., red LED 50R-1, green LED 50G-1, blue LED 50B-1) bonded to the first regions 111-1, 121-1, 131-1 of the first pixel 100-1 may correspond to the plurality of sub-pixels (red, green, and blue sub-pixels) constituting the first pixel 100-1. Also, the plurality of first LEDs (e.g., red LED 50R-2, green LED 50G-2, blue LED 50B-2) bonded to the first regions 111-2, 121-2, 131-2 of the second pixel 100-2 may correspond to the plurality of sub-pixels (red, green, and blue sub-pixels) constituting the second pixel 100-2.

[0129] Meanwhile, the black matrix layer 60 may be formed in the remaining regions on the adhesive layer 30 except for the regions where the plurality of first LEDs (eg, red LED 50R-1, green LED 50G-1, blue LED 50B-1, red LED 50R-2, green LED 50G-2, blue LED 50B-2) are formed.

[0130] at the same time, Figure 5A and Figure 5B The thickness (or height) of the black matrix layer 60 shown in the figures is merely an example and is not limited thereto, and may be implemented in various variations, such as a case where the upper portion of the black matrix layer 60 becomes flat without a height difference according to the thickness (or height) of the plurality of LEDs 50 or a case where the black matrix layer 60 has the same thickness as that of the LED 50.

[0131] At the same time, the size of each of the plurality of electrode pads 22 (e.g., the electrode pad 22R-1 and the electrode pad 22R-2 corresponding to the first red LED, respectively) is larger than the size of the first LED (e.g., the red LED 50R-1, the green LED 50G-1, the blue LED 50B-1, the red LED 50R-2, the green LED 50G-2, the blue LED 50B-2). That is, each of the first region (e.g., the first region 111-1, 111-2, 121-1, 121-2, 131-1, 131-2) and the second region (e.g., the second region 112-1, 112-2, 122-1, 122-2, 132-1, 132-2) may have a size for mounting the first LED or the second LED.

[0132] In addition, the first region (e.g., first region 111-1, 111-2, 121-1, 121-2, 131-1, 131-2) and the second region (e.g., second region 112-1, 112-2, 122-1, 122-2, 132-1, 132-2) of each of the plurality of electrode pads 22 may be electrically connected to each other. That is, each electrode pad 22 may be formed to be long in one direction (e.g., width direction, etc.).

[0133] At the same time, refer to Figure 4B , will be assumed in Figure 4A The description will be made on the case where, among the plurality of first LEDs shown, the green LED 50G-1 bonded to the first region 121-1 of the first pixel 100-1 and the red LED 50R-2 bonded to the first region 111-2 of the second pixel 100-2 are defective.

[0134] Here, the defective green LED 50G-1 of the first pixel 100-1 and the red LED 50R-2 of the second pixel 100-2 may be replaced by including the green LED 50G-3 bonded to the second region 122-1 of the first pixel 100-1 and the red LED 50R-3 bonded to the second region 112-2 of the second pixel 100-2 in the display module 1. Here, the defective green LED 50G-1 of the first pixel 100-1 and the red LED 50R-2 of the second pixel 100-2 may be removed by a laser method or the like.

[0135] In this case, the black matrix layer 60 may also be formed in the remaining areas on the adhesive layer 30 except for the areas where multiple first LEDs (e.g., red LED 50R-1, green LED 50G-1, blue LED 50B-1, red LED 50R-2, green LED 50G-2, blue LED 50B-2) are formed.

[0136] Figure 6 is a flowchart for illustrating a method of manufacturing a display panel according to an embodiment of the present disclosure.

[0137] Reference Figure 6According to the present disclosure, a manufacturing method of a display module 1 including a plurality of pixels (for example, including a first pixel 100-1 and a second pixel 100-2) may include the following steps: forming a driving circuit layer 20 including a plurality of driving circuits 21 and a plurality of electrode pads 22 electrically connected to each of the plurality of driving circuits 21 on a substrate 10 (S610); forming an adhesive layer 30 on the driving circuit layer 20 (S620); transferring each of the plurality of LEDs 50 to an area of ​​the adhesive layer 30 corresponding to the plurality of electrode pads 22 (S630); attaching a black matrix layer 70 attached to a film 80 to the adhesive layer 30 and the plurality of LEDs 50 formed between the plurality of LEDs 50 (S640); and removing the black matrix layers 71, 72 attached to the plurality of LEDs 50 together with the film 80, thereby forming a black matrix layer 60 on the adhesive layer 30 formed between the plurality of LEDs 50 (S650).

[0138] Here, each of a plurality of pixels (for example, including a first pixel 100-1 and a second pixel 100-2) may include a plurality of sub-pixels, and each of a plurality of electrode pads 22 may include one of a first region 111, 121, 131 for bonding a first LED corresponding to a sub-pixel among the plurality of sub-pixels and one of a second region 112, 122, 132 for bonding a second LED corresponding to the sub-pixel when the first LED is defective.

[0139] Each step of the method for manufacturing a display module according to the present disclosure will be described below in conjunction with the accompanying drawings.

[0140] 7A to 7C is a schematic diagram for illustrating a driving circuit layer according to an embodiment of the present disclosure. Here, Figure 7B and Figure 7C yes Fig. 7A Cross-sectional view along line C1-C2 in FIG.

[0141] Reference 7A to 7C First, in operation S610, a driving circuit layer 20 may be formed on a substrate 10. Here, the driving circuit layer 20 may include a plurality of driving circuits 21 and a plurality of electrode pads 22 electrically connected to each of the plurality of driving circuits 21.

[0142] The plurality of driving circuits 21 are configured as circuits for transmitting driving signals to make the plurality of LEDs 50 emit light, and may be formed by various processes such as drilling, plating, exposure, etching, lamination, etc. The plurality of driving circuits 21 may be implemented as various forms of circuits according to the design of the circuits.

[0143] The plurality of electrode pads 22 are electrically connected to the plurality of driving circuits 21 , and may be implemented as various materials having high conductivity, such as Cu, Au, Ag, indium tin oxide (ITO), and the like.

[0144] To this end, the plurality of electrode pads 22 may be formed through a plating process, a deposition process, a sputtering process, etc. In addition, the plurality of electrode pads 22 may be formed in positions for bonding (or transferring) the plurality of LEDs 50 .

[0145] Furthermore, each of the plurality of electrode pads 22 may include one of the first regions 111-1, 111-2, 121-1, 121-2, 131-1, 131-2 for bonding a first LED corresponding to one of the plurality of sub-pixels and ...2, 111-2, 121-1, 131-2 for bonding a first LED corresponding to one of the plurality of sub-pix Fig. 7A and Fig. 8A ) One of the second regions 112-1, 112-2, 122-1, 122-2, 132-1, 132-2 of the second LED corresponding to the sub-pixel is joined. Here, the second LED may be an LED that emits light of the same color as the first LED.

[0146] Here, the size of each of the plurality of electrode pads 22 is larger than the size of the first LED. That is, each of the first region 111, 121, 131 and the second region 112, 122, 132 may have a size for mounting the first LED or the second LED.

[0147] In addition, the first region 111, 121, 131 and the second region 112, 122, 132 of each of the plurality of electrode pads 22 may be electrically connected to each other. That is, each electrode pad 22 may be formed to be long in one direction (eg, width direction, etc.).

[0148] Meanwhile, according to one embodiment of the present disclosure, Figure 7B As shown, a plurality of electrode pads 22 may be formed to protrude on the upper surface of the driving circuit layer 20, or according to another embodiment of the present disclosure, as shown in FIG. Figure 7C As shown, the plurality of electrode pads 22 may be formed not to protrude on the upper surface of the driving circuit layer 20 (ie, to be flat without a height difference from the upper surface of the driving circuit layer 20 ).

[0149] FIG. 8A to FIG. 8D Schematic diagram for illustrating a method for forming an adhesive layer according to an embodiment of the present disclosure. Here, Figure 8B A case where the adhesive layer 30 according to an embodiment of the present disclosure is an ACF 31 is shown, and Figure 8C and Fig.8D3 shows a case where the adhesive layer 30 according to an embodiment of the present disclosure is a non-conductive film 35. Here, FIG. 8B to FIG. 8D According to the embodiment Fig. 8A Cross-sectional view along line D1-D2 in FIG.

[0150] Reference FIG. 8A to FIG. 8D , after operation S610 , an adhesive layer 30 may be formed on the driving circuit layer 20 in operation S620 .

[0151] For example, the adhesive layer 30 may be formed as an adhesive film (not shown) laminated on the driving circuit layer 20. Here, the adhesive film may be Figure 8B ACF 31 or Figure 8C and Fig.8D The non-conductive film 35 is shown.

[0152] Here, lamination may refer to a method of forming a layer by covering a film on the surface of an object as an object. Specifically, lamination may adopt a roll lamination method in which an adhesive film located on the drive circuit layer 20 passes through a roller together with the drive circuit layer 20 and the adhesive film is attached to the drive circuit layer 20, a vacuum lamination method in which an adhesive film is attached to the drive circuit layer 20 by a vacuum method, etc. However, these are only examples, and lamination is not limited thereto, but may be achieved in various ways, such as rollers, vacuum, heating or cooling, or a combination thereof.

[0153] Meanwhile, after the adhesive film is attached to the driving circuit layer 20, if bubbles are present between the adhesive film and the driving circuit layer 20, the bubbles may be removed by using an autoclave method. For example, the bubbles may be removed by a constant temperature pressurization process in which pressure is applied while maintaining a constant temperature or a heating pressurization process in which pressure is applied while increasing the temperature.

[0154] Reference Figure 8B , showing a case where the adhesive layer 30 according to an embodiment of the present disclosure is an ACF 31 .

[0155] Reference Figure 8B , the ACF 31 formed on the driving circuit layer 20 as above may include the conductive material 32 . Here, the conductive material 32 may be arranged randomly or at regular intervals, and some of the conductive material 32 may be arranged on the electrode pad 22 .

[0156] Reference Figure 8C and Fig.8D , showing a case where the adhesive layer 30 according to an embodiment of the present disclosure is a non-conductive film 35 .

[0157] Reference Figure 8C and Fig.8D The non-conductive film 35 may include a flux. Here, the flux may remove an oxide film generated when the bump 40 is melted.

[0158] To this end, the bumps 40 may be applied to a plurality of LEDs 50 (eg, Fig. 9C and Fig. 10B The electrode of each of the red LED 50R, green LED 50G, and blue LED 50B shown in FIG. 1 is applied to a plurality of electrode pads 22 (see FIG. 1 ). Fig.8D , Fig.9D , Fig. 10C ). In this case, you can Figure 8C The bump 40 is applied after the adhesive layer 30 is formed on the driving circuit layer 20 (after operation S620), or the bump 40 may be applied as shown in FIG. Fig.8D It is shown that the bump 40 is applied before the adhesive layer 30 is formed on the driving circuit layer 20 (before operation S620 ).

[0159] 9A to 9D is a schematic diagram for illustrating a method for transferring an LED according to an embodiment of the present disclosure. Here, Fig. 9B A case where the adhesive layer 30 according to an embodiment of the present disclosure is an ACF 31 is shown, and Fig. 9C and Fig.9D 3 shows a case where the adhesive layer 30 according to an embodiment of the present disclosure is a non-conductive film 35. Here, FIG. 9B to FIG. 9D According to the embodiment Fig. 9A Cross-sectional view along line E1-E2 in FIG.

[0160] Reference 9A to 9D After operation S620, each of the plurality of LEDs 50 (e.g., red LED 50R, green LED 50G, blue LED 50B) may be transferred to a region of the adhesive layer 30 corresponding to the plurality of electrode pads 22 in operation S630. Here, each of the plurality of LEDs 50 may be a micro LED of a flip chip structure in which an electrode 55 (e.g., electrode 55R of the red LED 50R) is formed at a lower portion.

[0161] Specifically, the plurality of LEDs 50 may be transferred to regions of the adhesive layer 30 corresponding to the plurality of electrode pads 22 such that they are electrically connected to the plurality of electrode pads 22 through operation S640.

[0162] For example, the plurality of LEDs 50 may be formed in a region where electrode pads of the plurality of LEDs 50 and the plurality of electrode pads 22 of the driving circuit 21 directly contact each other or indirectly contact each other through a conductive material. Here, the conductive material may be the conductive material 32 or the bump 40.

[0163] Here, the area in which the multiple LEDs 50 and the multiple electrode pads 22 of the driving circuit 21 are electrically connected can be a first area in the first area 111, 121, 131 of each of the multiple pixels (for example, including the first pixel 100-1 and the second pixel 100-2) present on the multiple electrode pads 22 or a second area in the second area 112, 122, 132 of each of the multiple pixels (for example, including the first pixel 100-1 and the second pixel 100-2).

[0164] FIG. 10A to FIG. 10C is a schematic diagram for illustrating a method of attaching a film according to an embodiment of the present disclosure. Fig.11A and Fig. 11B Schematic diagram for illustrating a method for forming a black matrix layer according to an embodiment of the present disclosure. Fig. 10A and Fig.11A A case where the adhesive layer 30 according to an embodiment of the present disclosure is an ACF 31 is shown, and Fig. 10B , Fig. 10C and Fig. 11B A case in which the adhesive layer 30 according to the embodiment of the present disclosure is a non-conductive film 35 is shown.

[0165] Reference FIG. 10A to FIG. 10C After operation S630, in operation S640, the black matrix layer 70 attached to the film 80 can be attached to the area (or referred to as "gap area") of the adhesive layer 30 formed between multiple LEDs 50 (e.g., red LED 50R, green LED 50G, blue LED 50B) and the multiple LEDs 50.

[0166] Here, the black matrix layer 60 may be attached to the adhesive layer 30 formed between the plurality of LEDs 50R, 50G, 50B and the plurality of LEDs 50R, 50G, 50B through a thermal compression process.

[0167] Here, the heat pressing process may refer to a method of positioning the black matrix layer 70 on the adhesive layer 30 formed between the plurality of LEDs 50 and the plurality of LEDs 50, and applying pressure and heat to the film 80 attached to the black matrix layer 70 in the direction of the substrate 10, such as FIG. 10A to FIG. 10C shown.

[0168] To this end, the film 80 may be a release film having heat resistance, and it may be implemented as, for example, a film including at least one of polymers such as polytetrafluoroethylene, polyimide, polyolefin, and the like.

[0169] Later, when heat and pressure are applied through the hot pressing process, it can be made into FIG. 11A to FIG. 11B The form shown.

[0170] In the following, reference will be made to Fig.11A A case is described in which the adhesive layer 30 includes the ACF 31. Here, the ACF 31 may include a conductive material 32, and the conductive material 32 may be implemented in a form such as plastic on which conductive particles are coated.

[0171] In this case, through a hot pressing process, a black matrix layer 71 (previously referred to as a black matrix layer 70) can be attached to an adhesive layer 30 formed between a plurality of LEDs 50 (e.g., a red LED 50R, a green LED 50G, a blue LED 50B) and a plurality of LEDs 50, and each of the plurality of LEDs 50 can be electrically connected to a plurality of electrode pads 22 through a conductive material 32.

[0172] Here, the plurality of LEDs 50 and the plurality of electrode pads 22 may respectively contact the conductive material 32 present therebetween, and thus, the plurality of LEDs 50 may be electrically connected to the plurality of electrode pads 22 through the conductive material 32 .

[0173] Furthermore, the ACF 31 may be cured by a thermal pressing process, and its adhesive force may be improved.

[0174] In the following, reference will be made to Fig. 11B A case is described in which the adhesive layer 30 includes the non-conductive film 35. Here, the non-conductive film 35 may include a flux, and the flux may remove an oxide film generated when the bump 40 is melted.

[0175] In this case, through a hot pressing process, a black matrix layer 71 (previously referred to as a black matrix layer 70) can be attached to an adhesive layer 30 formed between the plurality of LEDs 50 and the plurality of LEDs 50, and a bump 40 applied to an electrode of each of the plurality of LEDs 50 or a bump 40 applied to a plurality of electrode pads 22 can be melted, and each of the plurality of LEDs 50 can be electrically connected to the plurality of electrode pads 22 through the bump 40 when the bump 40 is in a molten form.

[0176] Here, when the bump 40 melts, an oxide film may be generated on the surface. In this case, the oxide film of the bump 40 (or the oxide film on the surface) may cause such a problem that the wettability of the solder constituting the bump 40 is reduced, and a gap is generated between the bump 40 and the electrode and the bonding strength is reduced.

[0177] In this case, the oxide film generated when the bump 40 is melted can be removed by the flux. In addition, the flux can remove the oxide film or prevent the generation of the oxide film in a physical and chemical manner.

[0178] FIG. 12A to FIG. 12C is a schematic diagram for illustrating a display module manufactured according to an embodiment of the present disclosure. Here, Fig. 12BA case where the adhesive layer 30 according to an embodiment of the present disclosure is an ACF 31 is shown, and Fig. 12C 3 shows a case where the adhesive layer 30 according to an embodiment of the present disclosure is a non-conductive film 35. Here, FIG. 12B to FIG. 12C According to the embodiment Fig. 12A Cross-sectional view along line F1-F2 in FIG.

[0179] Reference FIG. 12A to FIG. 12C , after operation S640, in operation S650, the black matrix layer 72 (e.g., a portion of the black matrix layer 71) attached to the plurality of LEDs 50 (e.g., the red LED 50R, the green LED 50G, the blue LED 50B) can be removed together with the film 80, and the black matrix layer 60 (e.g., the remaining portion of the black matrix layer 71) can be formed on the adhesive layer 30 formed between the plurality of LEDs 50.

[0180] Here, the adhesive force between the adhesive layer 30 and the black matrix layer 60 attached to the adhesive layer 30 may be stronger than the adhesive force between the film 80 and the black matrix layer 72 attached to the film 80. Therefore, when the film 80 is removed, the black matrix layer 60 attached to the adhesive layer 30 may remain.

[0181] Furthermore, the adhesive force between the plurality of LEDs 50 and the black matrix layer 72 attached to the plurality of LEDs 50 may be weaker than the adhesive force between the film 80 and the black matrix layer 72. Therefore, when the film 80 is removed, the black matrix layer 72 attached to the plurality of LEDs 50 may be removed together with the film 80.

[0182] According to the embodiments of the present disclosure described above, since the black matrix layer 60 is formed by forming the adhesive layer 30 in the entire region of the driving circuit layer 20, attaching the plurality of LEDs 50 on the adhesive layer 30, and using the adhesive force of the exposed portion of the adhesive layer 30, it is possible to minimize the generation of the BM opening region in which the black matrix is ​​not formed between the plurality of LEDs 50. That is, by forming the black matrix layer 60 without tolerance in all regions except the region where the LEDs are mounted, it is possible to maximize the region in which the black matrix layer 60 is formed, and therefore, the black expression of the display can be maximized, and the contrast of the display can be improved.

[0183] Furthermore, in the display module and the manufacturing method thereof according to the embodiment of the present disclosure, the LED and the electrode pads of the driving circuit are electrically connected at the same time when the BM is formed, and thus, there are effects of simplifying the process and reducing the cost.

[0184] FIG. 13A to FIG. 13C Schematic diagram for illustrating a method for forming a black matrix layer according to an embodiment of the present disclosure. Fig.13AWhen the black matrix layer 72 ′ attached to the plurality of LEDs 50 (eg, the red LED 50R, the green LED 50G, and the blue LED 50B) is removed in operation S650 , a portion of the black matrix layer 72 ′ may remain on the plurality of LEDs 50 .

[0185] In this case, if Fig. 13B As shown, a tape 90 may be attached to the black matrix layer 72 ′ formed between and over the plurality of LEDs 50 .

[0186] Afterwards, if Fig. 13C As shown, the black matrix layer 73 ′ remaining on the plurality of LEDs 50 may be removed together with the tape 90 .

[0187] Here, the adhesive force between the tape 90 and the black matrix layer 72' may be weaker than the adhesive force between the black matrix layer 72' and the adhesive layer 30. Therefore, when the tape 90 is removed, a portion of the black matrix layer 72' attached to the adhesive layer 30 (e.g., the black matrix layer 60') may remain.

[0188] In addition, the adhesive force between the plurality of LEDs 50 and the black matrix layer 72′ attached to the plurality of LEDs 50 may be weaker than the adhesive force between the tape 90 and the black matrix layer 72′. Therefore, when the tape 90 is removed, a portion of the black matrix layer 72′ attached to the plurality of LEDs 50 (the black matrix layer 73′) may be removed together with the tape.

[0189] At the same time, FIG. 13A to FIG. 13C , an embodiment in which the adhesive layer 30 includes an anisotropic conductive film (ACF) 31 is shown, but this is merely an example, and an embodiment in which the adhesive layer 30 includes a non-conductive film 35 can also be realized.

[0190] According to the embodiment of the present disclosure described above, the black matrix layer 60 is not formed on the plurality of LEDs 50 , and thereby, a defect that light emitted from the plurality of LEDs 50 is covered by the black matrix layer 60 can be prevented.

[0191] Furthermore, according to the above-described various embodiments of the present disclosure, in a display module and a method of manufacturing the same, a BM layer is formed without tolerance in a region excluding an LED, and thus the expression of black can be maximized and the contrast of a display can be improved.

[0192] In addition, in the display module and the manufacturing method thereof according to the embodiment of the present disclosure, the LED and the electrode pads of the driving circuit are integrally connected while forming the BM over a large area, and thus, there are effects of simplifying the process and reducing the cost.

[0193] The display module according to the present disclosure can be applied by being installed in wearable devices, portable devices, handheld devices, and electronic products or electronic components that require various types of displays in a single unit. In addition, by assembling and arranging in multiple units (matrix type, etc.), the display module can be applied to display devices such as monitors of personal computers (PCs), mobile phones, high-resolution televisions and signage, electronic boards, etc.

[0194] Various embodiments of the present disclosure may be implemented as software including instructions stored in a machine-readable storage medium, which can be read by a machine (e.g., a computer). A machine refers to a device that calls instructions stored in a storage medium and is capable of operating according to the called instructions, and the device may include an electronic device according to the above-mentioned embodiments. In the case where the instructions are executed by a processor, the processor may perform the functions corresponding to the instructions by itself, or perform the functions corresponding to the instructions by using other components under its control. The instructions may include code generated or executed by a compiler or interpreter. A storage medium that can be read by a machine may be provided in the form of a non-transitory storage medium. Here, the term "non-transitory" only means that the storage medium does not contain signals and is tangible, but does not mean whether the data is stored in the storage medium semi-permanently or temporarily.

[0195] In addition, the methods according to various embodiments of the present disclosure may be provided while being included in a computer program product. A computer program product refers to a product that can be traded between a seller and a buyer. A computer program product may be in the form of a machine-readable storage medium (e.g., a compact disc read-only memory (CD-ROM)) or through an application store (e.g., PlayStore). TM ) Online distribution. In the case of online distribution, at least a portion of the computer program product may be at least temporarily stored in a storage medium such as a memory of a manufacturer's server, an application store's server, and a relay server, or may be temporarily generated.

[0196] In addition, each component (e.g., module or program) according to various embodiments of the present disclosure may include a single object or multiple objects or be composed of a single object or multiple objects. In addition, in the above-mentioned subcomponents, some subcomponents may be omitted, or other subcomponents may also be included in various embodiments. Generally or additionally, some components (e.g., modules or programs) may be integrated into objects, and the functions performed by each component before integration may be performed in the same or similar manner. The operations performed by the modules, programs or other components according to various embodiments may be performed sequentially, in parallel, repeatedly or heuristically. Alternatively, at least some operations may be performed or omitted in different orders, or other operations may be added.

Claims

1. A method for manufacturing a display module comprising a plurality of pixels, the method comprising: forming a driving circuit layer on the substrate, wherein the driving circuit layer includes a plurality of driving circuits and a plurality of electrode pads electrically connected to the plurality of driving circuits; forming an adhesive layer on the driving circuit layer; transferring each of a plurality of light emitting diodes (LEDs) onto a corresponding region of the adhesive layer corresponding to a corresponding electrode pad of the plurality of electrode pads; and A black matrix layer is formed on the adhesive layer between the plurality of LEDs in the following manner: attaching a black matrix forming layer attached to a film onto the plurality of LEDs and onto portions of the adhesive layer formed between the plurality of LEDs, and removing a first portion of the black matrix forming layer attached to the plurality of LEDs together with the film so that a second portion of the black matrix forming layer remains between the plurality of LEDs as the black matrix layer, wherein the adhesive force between the adhesive layer and the black matrix forming layer is stronger than the adhesive force between the film and the black matrix forming layer, wherein each pixel of the plurality of pixels comprises a plurality of sub-pixels, and Each of the plurality of electrode pads includes a first region for bonding a first LED corresponding to a sub-pixel among the plurality of sub-pixels and a second region for bonding a second LED corresponding to the sub-pixel based on the first LED being defective.

2. The method of claim 1, wherein the attaching comprises: The black matrix forming layer is attached to the portion of the adhesive layer formed between the plurality of LEDs and to the plurality of LEDs through a heat pressing process.

3. The method according to claim 2, wherein The adhesive layer includes an anisotropic conductive film ACF including a conductive material, and The attachment further comprises: Each of the plurality of LEDs is electrically connected to the plurality of electrode pads through the conductive material.

4. The method according to claim 2, wherein The adhesive layer includes a non-conductive film containing flux, The attachment further comprises: melting a bump applied on an electrode of each of the plurality of LEDs or on the plurality of electrode pads, and electrically connecting each of the plurality of LEDs to the plurality of electrode pads through the bumps when the bumps are in a molten form, and The flux is configured to remove an oxide film generated when the bump is melted.

5. The method of claim 1, wherein the removing comprises: After removing the film from the black matrix forming layer, attaching a tape to the black matrix forming layer, and removing the remaining portion of the black matrix forming layer attached to the plurality of LEDs together with the tape from the plurality of LEDs so that the second portion of the black matrix forming layer remains between the plurality of LEDs as the black matrix layer, The adhesive force between the adhesive tape and the black matrix forming layer is weaker than the adhesive force between the black matrix forming layer and the adhesive layer. The method of claim 1 , wherein the second LED is configured to emit light of the same color as the first LED.

7. The method according to claim 1, wherein A size of each of the plurality of electrode pads is larger than a size of the first LED, and The first region and the second region are electrically connected. 8 . The method according to claim 1 , wherein each of the plurality of LEDs is a micro LED of a flip chip structure, wherein an electrode is formed at a lower portion of the flip chip structure.

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