Method of manufacturing a display device

Abstract

The present application provides a manufacturing method of a display device that can shorten the tact time. The manufacturing method has a transfer step of transferring and arranging a single piece of an anisotropic conductive adhesive layer provided on a substrate having a laser transmissivity opposite to a wiring substrate by irradiating a laser from the substrate side to the single piece of the anisotropic conductive adhesive layer to the prescribed position of the wiring substrate; and a mounting step of mounting a light emitting element on the single piece arranged at the prescribed position of the wiring substrate. By the irradiation of the laser, the single piece of the anisotropic conductive adhesive layer can be transferred and arranged with high precision and high efficiency.

Description

Technical Field

[0001] This technology relates to a method for manufacturing a display device composed of an arrangement of light-emitting elements. In particular, it relates to a method for manufacturing a display device composed of an arrangement of LED elements such as small LEDs and micro LEDs. This application claims priority based on Japanese Patent Application No. 2021-054138, filed on March 26, 2021, which is incorporated herein by reference. Background Technology

[0002] Previously, display devices have been proposed that arrange multiple light-emitting elements such as LEDs (Light Emitting Diodes) to form an array of light-emitting elements. Patent Document 1 discloses a process method for bonding LEDs using anisotropic conductive adhesives such as ACF (Anisotropic Conductive Film).

[0003] In the process described in Patent Document 1, since the ACF is bonded together with the component mounting surface of the substrate, the adhesive resin and conductive particles of the ACF remain between the LEDs. Therefore, when light transmittance is required for the light-emitting element array, it will hinder light transmission and fail to achieve excellent light transmittance.

[0004] On the other hand, if the ACF is only pasted directly below the LED, the pasting process alone will take a considerable amount of time, and the beat time will deteriorate.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: U.S. Patent Application Publication No. 2015 / 0255505. Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] This technology is proposed in view of the existing reality and provides a method for manufacturing a display device that can reduce cycle time.

[0010] Methods for solving problems

[0011] The manufacturing method of the display device involved in this technology includes the following steps: a transfer step in which an anisotropic conductive adhesive layer disposed on a laser-transmissive substrate is placed opposite a wiring substrate, and a laser is irradiated from the substrate side to transfer a single piece of the anisotropic conductive adhesive layer to a predetermined position on the wiring substrate and arrange them thereon; and an mounting step in which a light-emitting element is mounted on a single piece arranged at a predetermined position on the wiring substrate.

[0012] The manufacturing method of the display device involved in this technology includes the following steps: a transfer step in which an anisotropic conductive adhesive layer disposed on a laser-transmissive substrate is placed opposite to light-emitting elements arranged on a transfer substrate, and a laser is irradiated from the substrate side to transfer a single sheet of the anisotropic conductive adhesive layer onto the light-emitting elements arranged on the transfer substrate; a re-transfer step in which the light-emitting elements with the transferred single sheet are re-transferred onto the wiring substrate; and an mounting step in which light-emitting elements arranged at predetermined positions on the wiring substrate are mounted via the single sheet.

[0013] Invention Effects

[0014] According to this technology, anisotropic conductive adhesive layers can be transferred and arranged with high precision and efficiency by laser irradiation, thus reducing cycle time. Attached Figure Description

[0015] [ Figure 1 ] Figure 1 It is a schematic cross-sectional view showing the state in which the anisotropic conductive adhesive layer disposed on the substrate is facing the wiring substrate.

[0016] [ Figure 2 ] Figure 2 It is a schematic cross-sectional view showing the state in which anisotropic conductive adhesive layers are transferred onto a specified position on a wiring substrate and arranged by irradiating the substrate side with a laser.

[0017] [ Figure 3 ] Figure 3 It is a schematic cross-sectional view showing the state in which light-emitting elements are mounted on a single piece arranged at a specified position on a wiring substrate.

[0018] [ Figure 4 ] Figure 4 It is a schematic cross-sectional view showing the state in which monoliths of anisotropic conductive adhesive layers are transferred onto the wiring substrate according to the electrode positions and arranged by irradiating the substrate side with a laser.

[0019] [ Figure 5 ] Figure 5 It is a schematic cross-sectional view showing the state in which light-emitting elements are mounted on a single piece of a wiring substrate arranged in electrode units.

[0020] [ Figure 6 ] Figure 6 It is a schematic cross-sectional view showing the state in which the anisotropic conductive adhesive layer disposed on the substrate is opposite to the light-emitting elements arranged on the transfer substrate.

[0021] [ Figure 7 ] Figure 7 It is a schematic cross-sectional view showing an anisotropic conductive adhesive layer disposed on a substrate.

[0022] [ Figure 8 ] Figure 8 It is a schematic cross-sectional view showing the state in which an anisotropic conductive adhesive layer is transferred onto light-emitting elements arranged on a transfer substrate by irradiating a laser from the substrate side.

[0023] [ Figure 9 ] Figure 9 It is a schematic cross-sectional view showing the state of transferring a single light-emitting element onto a wiring substrate.

[0024] [ Figure 10 ] Figure 10 It is a microscopic photograph of a single piece of metal showing an anisotropic conductive adhesive layer arranged on a mother glass (sample glass).

[0025] [ Figure 11 ] Figure 11 yes Figure 4 The image shown is a magnified photograph of a metal microscope image. Detailed Implementation

[0026] Hereinafter, with reference to the accompanying drawings, the embodiments of the present technology will be described in detail in the following order.

[0027] 1. Manufacturing method of display device

[0028] 2. Example <1. Method for manufacturing a display device>

[0029] [First Implementation]

[0030] The manufacturing method of the display device according to the first embodiment includes the following steps: a transfer step in which an anisotropic conductive adhesive layer disposed on a laser-transmissive substrate is positioned opposite a wiring substrate, and a laser is irradiated from the substrate side to transfer individual sheets of the anisotropic conductive adhesive layer to predetermined positions on the wiring substrate and arrange them; and a mounting step in which light-emitting elements are mounted on the individual sheets arranged at predetermined positions on the wiring substrate. By irradiating with a laser, the individual sheets of the anisotropic conductive adhesive layer can be transferred and arranged with high precision and efficiency, thus shortening the cycle time.

[0031] The following is for reference Figures 1-3 The transfer process (A), in which anisotropic conductive adhesive layers are transferred to specified positions on a wiring substrate and arranged therein, and the mounting process (B), in which light-emitting elements are mounted on the individual layers arranged at specified positions on the wiring substrate, are described.

[0032] [Transfer Process (A)]

[0033] Figure 1 This is a schematic cross-sectional view showing the state in which the anisotropic conductive adhesive layer disposed on the substrate is facing the wiring board. For example... Figure 1As shown, firstly, in the transfer process (A), the anisotropic conductive adhesive layer substrate 10 is positioned opposite the wiring substrate 20.

[0034] The anisotropic conductive adhesive layer substrate 10 includes a substrate 11 and an anisotropic conductive adhesive layer 12, with the anisotropic conductive adhesive layer 12 provided on the surface of the substrate 11. The substrate 11 can be any substrate that is transmissive to laser light, and is preferably quartz glass with high transmittance across the entire wavelength range.

[0035] The anisotropic conductive adhesive layer 12 contains conductive particles 13 in the adhesive, for example. Furthermore, from the viewpoint of laser-based transferability, the anisotropic conductive adhesive layer 12 is preferably constructed in a way that allows for conductivity by neatly arranging the conductive particles 13 along the surface direction, and in a way that avoids short circuits. The neat arrangement of the conductive particles is preferably a regular arrangement. Japanese Patent No. 6119718 can be cited as an example. As the adhesive, examples include epoxy adhesives or acrylic adhesives, among which resins having a maximum absorption wavelength of 180 nm to 360 nm, or epoxy adhesives containing high-purity bisphenol A type epoxy resins, are preferred. A specific example of high-purity bisphenol A type epoxy resin is, for example, Mitsubishi Chemical Corporation's trade name "YL980". Furthermore, as the epoxy resin curing agent contained in the epoxy adhesive, cationic polymerization initiators such as aromatic sulfonate salts or anionic polymerization initiators are preferred. Specific examples of aromatic sulfonate-based cationic polymerization initiators include, for instance, the trade name "SI-60L" manufactured by Sanshin Chemical Industry Co., Ltd. Acrylic adhesives, on the other hand, are adhesives that utilize free radical polymerization reactions, such as those containing free radical polymerizable substances like (meth)acrylate compounds and free radical polymerization initiators like peroxides. From the viewpoint of heat resistance and adhesion required for use in display devices, epoxy adhesives are preferred. It should be noted that this description refers to thermosetting anisotropic conductive adhesive layers, but in cases where heat should be avoided in subsequent processes, photocurable anisotropic conductive adhesive layers can be used. In such cases, in addition to the aforementioned thermopolymerization initiators, photopolymerization initiators can also be used.

[0036] As the conductive particle 13, conductive particles that are known to be used in anisotropic conductive films can be appropriately selected for use. Examples include: metal particles such as nickel (melting point 1455℃), copper (melting point 1085℃), silver (melting point 961.8℃), gold (melting point 1064℃), palladium (melting point 1555℃), tin (melting point 231.9℃), nickel boride (melting point 1230℃), ruthenium (melting point 2334℃), and tin alloys, i.e., solder; metal-coated resin particles obtained by coating the surface of polymers and other resin particles with metals such as nickel, copper, silver, gold, palladium, tin, nickel boride, and ruthenium, wherein the polymer contains at least one monomer selected from polyamide, polybenzoguanamine, styrene, and divinylbenzene as monomer units; and metal-coated inorganic particles obtained by coating the surface of inorganic particles such as silica, alumina, barium titanate, zirconium oxide, carbon black, silicate glass, borosilicate glass, lead glass, soda lime glass, and aluminosilicate glass with metals such as nickel, copper, silver, gold, palladium, tin, nickel boride, and ruthenium. The aforementioned metal particles can be coated with the aforementioned metal. Furthermore, the metal layer in the metal-coated resin particles and metal-coated inorganic particles can be a single layer or formed from multiple layers of different types of metals.

[0037] For example, insulating coating treatment can be performed by coating these conductive particles with an insulating layer of resin or resin particles, inorganic particles, or other insulating particles. The particle size of the conductive particles 13 is appropriately varied according to the area of ​​the electrodes or bumps of the optical element or wiring substrate to which they are mounted, and is preferably 1 to 30 μm, more preferably 1 to 10 μm, and particularly preferably 1 to 3 μm. In the case of mounting micro LED elements, since the area of ​​the electrodes or bumps is small, the particle size is preferably 1 to 2.5 μm, more preferably 1 to 2.2 μm, and particularly preferably 1 to 2 μm. The particle size can be determined by measuring more than 200 particles under a microscope (optical microscope, metal microscope, electron microscope, etc.) and calculating the average particle size.

[0038] Furthermore, as described above, the metal coating thickness in conductive particles coated with metal on resin particles or inorganic particles is preferably 0.005 μm or more, more preferably 0.01 μm or more, preferably 10 μm or less, more preferably 1 μm or less, and even more preferably 0.3 μm or less. When the metal coating is multilayered, this coating thickness is the overall thickness of the metal coating. If the coating thickness is above or below the aforementioned lower limit and below the aforementioned upper limit, sufficient conductivity is easily obtained, and the conductive particles do not become overly rigid, making it easy to effectively utilize the characteristics of the aforementioned resin particles or inorganic particles.

[0039] The aforementioned coating thickness can be measured, for example, by observing the cross-section of the conductive particles using a transmission electron microscope (TEM). Regarding the coating thickness, it is preferable to calculate the average coating thickness at any five points as the coating thickness of one conductive particle; more preferably, it is preferable to calculate the average thickness of the entire coating area as the coating thickness of one conductive particle. The coating thickness is preferably obtained by calculating the average coating thickness of any ten conductive particles.

[0040] Furthermore, examples of conductive particle shapes include spherical, ellipsoidal, spiked, and irregular shapes. Among these, spherical conductive particles are preferred from the perspective of easy control over particle size or particle size distribution. These conductive particles may have protrusions on their surface to improve connectivity.

[0041] The thickness of the anisotropic conductive adhesive layer varies appropriately depending on the height of the electrodes or bumps on the optical element or wiring substrate to which it is mounted, and is preferably 1 to 30 μm, more preferably 1 to 10 μm. In the case of mounting micro LED elements, since the height of the electrodes or bumps is low, the thickness is preferably 1 to 6 μm, more preferably 1 to 5 μm, and particularly preferably 1 to 4 μm.

[0042] By forming the anisotropic conductive adhesive layer into a film, it is easy to apply the anisotropic conductive adhesive layer to the aforementioned substrate. From an operational point of view, it is preferable to have a release film such as a polyethylene terephthalate film on one or both sides of the anisotropic conductive adhesive layer.

[0043] Anisotropic conductive adhesive layers can be laminated on a substrate by transferring these film-like anisotropic conductive adhesive layers onto the substrate, or by fabricating anisotropic conductive adhesive layers on the substrate. Examples of methods for fabricating anisotropic conductive adhesive layers on a substrate include: coating a solution of anisotropic conductive adhesive onto the substrate and drying it; or forming an adhesive layer without conductive particles on the substrate and fixing conductive particles onto the resulting adhesive layer.

[0044] The wiring substrate 20 has a first conductivity type circuit pattern and a second conductivity type circuit pattern on the substrate 21. The light-emitting elements are arranged in a manner that constitutes a sub-pixel unit of one pixel. For example, a first electrode 22 and a second electrode 23 are respectively located at the positions corresponding to the first conductivity type electrode on the p side and the second conductivity type electrode on the n side. Furthermore, the wiring substrate 20 forms, for example, matrix wiring data lines, address lines, and other circuit patterns, which can turn the light-emitting elements corresponding to each sub-pixel of one pixel on / off. One pixel can be composed of, for example, three sub-pixels (R (red), G (green), B (blue), four sub-pixels (RGBW (white) and RGBY (yellow), or two sub-pixels (RG and GB). In addition, the wiring substrate 20 is preferably a light-transmitting substrate, the substrate 21 is preferably glass, PET (polyethylene terephthalate), etc., and the circuit pattern, the first electrode 22 and the second electrode 23 are preferably transparent conductive films such as ITO (indium-tin oxide), IZO (indium-zinc oxide), ZnO (zinc oxide), IGZO (indium-gallium-zinc oxide).

[0045] Figure 2 This is a schematic cross-sectional view showing the state in which anisotropic conductive adhesive layers are transferred and arranged monolithically onto a wiring substrate by laser irradiation from the substrate side. For example... Figure 2 As shown, in the transfer process (A), a laser is irradiated from the substrate 11 side to transfer the individual pieces 12a of the anisotropic conductive adhesive layer 12 to a predetermined position on the wiring substrate 21 and arrange them.

[0046] Here, in order to efficiently transfer individual sheets of anisotropic conductive adhesive layers from a substrate, the anisotropic conductive adhesive layers disposed on the substrate can be pre-treated to form a matrix arrangement of individual sheets. One such pre-treatment method is to create a grid-like pattern of multiple longitudinal and transverse cuts intersecting on the anisotropic conductive adhesive layers. These cuts can be created mechanically or chemically. Alternatively, they can be created by laser ablation. By performing this treatment, multiple individual sheets of anisotropic conductive adhesive layers can be formed on the substrate in a matrix arrangement, facilitating laser transfer of the individual sheets. It should be noted that the cuts do not necessarily need to be deep enough to expose the substrate; even cuts that do not expose the substrate will improve laser transferability. This pre-treatment can be performed after the anisotropic conductive adhesive layers are formed on the substrate, or before the anisotropic conductive adhesive layers are formed on the substrate, i.e., during the stage of forming the film-like anisotropic conductive adhesive layers.

[0047] In the transfer process (A), the individual sheets 12a of the anisotropic conductive adhesive layer 12 can be arranged as a single pixel unit (e.g., as a single pixel in an RGB group), or as sub-pixel units constituting a single pixel (e.g., arbitrary RGB units). This allows for the arrangement of light-emitting element arrays ranging from high PPI (Pixels Per Inch) to low PPI.

[0048] Furthermore, in the transfer process (A), it is preferable to arrange the anisotropic conductive adhesive layer 12 as a single sheet 12a with one or more pixel units. For example, in the case of RGB, the light-emitting elements are arranged in groups of 3 pixels or in groups of 6 pixels, which include 3 pixels of redundant circuitry containing RGB. Therefore, the anisotropic conductive film can be transferred to a group of 6 pixels, or it can be transferred in one pixel unit, or it can be further arranged in electrode units. On the other hand, in order to improve the yield, the anisotropic conductive film can be transferred in a range that does not compromise transparency, for example, a range of 1 mm × 1 mm.

[0049] It should be noted that, in the case of a monolithic anisotropic conductive adhesive layer arranged in units of one pixel, by making the film-like anisotropic conductive adhesive layer into a strip and setting its width to one pixel, the aforementioned cut can be made to be in only one direction (the transverse direction of the strip). The bandwidth of this one-pixel width also depends on the spacing between pixels, but it does not refer to a length equal to the size of one pixel, but rather to a length that does not interfere with adjacent pixels.

[0050] Furthermore, the distance between the individual wafers arranged at predetermined positions on the wiring substrate 20 is preferably 3 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more. Additionally, the upper limit of the distance between the individual wafers is preferably 3000 μm or less, more preferably 1000 μm or less, and even more preferably 500 μm or less. If the distance between the individual wafers is too small, it is preferable to adhere the anisotropic conductive film to the entire surface of the wiring substrate 20; if the distance between the individual wafers is too large, it is preferable to adhere the anisotropic conductive film to predetermined positions on the wiring substrate 20. The distance between the individual wafers can be measured using microscopic observation (optical microscope, metal microscope, electron microscope, etc.).

[0051] In the transfer of the anisotropic conductive adhesive layer 12 onto a single sheet 12a, a LIFT (Laser-Induced Forward Transfer) device can be used, for example. The LIFT device includes, for example: a telescope that parallelizes the pulsed laser emitted from a laser device; a shaping optics system that shapes the spatial intensity distribution of the pulsed laser passing through the telescope to a uniform state; a mask that allows the pulsed laser shaped by the shaping optics system to pass through in a predetermined pattern; a field-directing lens located between the shaping optics system and the mask; and a projection lens that reduces and projects the laser patterned by the mask onto a donor substrate. The anisotropic conductive adhesive layer substrate 10, serving as the donor substrate, is held on the donor stage, and the wiring substrate 21, serving as the receiver substrate, is held on the receiver stage. The distance between the anisotropic conductive adhesive layer 12 and the wiring substrate 20 is preferably 10–1000 μm, more preferably 50–500 μm, and even more preferably 80–200 μm.

[0052] As a laser device, an excimer laser with an oscillation wavelength of 180 nm to 360 nm can be used, for example. The oscillation wavelength of the excimer laser is, for example, 193 nm, 248 nm, 308 nm, or 351 nm, and can be appropriately selected from these oscillation wavelengths according to the light absorption properties of the material of the anisotropic conductive adhesive layer 12.

[0053] The mask is used to form a pattern of windows of a specified size at a specified interval, with the projection of the boundary surface between the substrate 11 and the anisotropic conductive adhesive layer 12 becoming the desired laser arrangement. In the mask, for example, the pattern is applied to the substrate 11 by chromium plating, the window portions without chromium plating transmit the laser, while the portions with chromium plating block the laser.

[0054] The light emitted from the laser device enters the telescope optics system and propagates towards the previous shaping optics system. The laser light, about to enter the shaping optics system, is adjusted by the telescope optics system to be approximately parallel light at any position within the range of movement of the donor stage's X-axis, and therefore usually enters the shaping optics system at approximately the same size and angle (perpendicular).

[0055] The laser beam, after passing through the shaping optical system, is incident on the mask via a field lens that forms the image-side telecentric reduction projection optical system in combination with the projection lens. The propagation direction of the laser beam, after passing through the mask pattern, is changed to vertically downward by the incident mirror and then incident on the projection lens. The laser beam emitted from the projection lens is incident from the substrate 11 side and is accurately projected onto the anisotropic conductive adhesive layer 12 formed on its surface (below) at a predetermined position with a reduced size of the mask pattern.

[0056] The pulse energy of the laser used for imaging the interface between the anisotropic conductive adhesive layer and the substrate is preferably 0.001–2 J, more preferably 0.01–1.5 J, and even more preferably 0.1–1 J. The flux is preferably 0.001–2 J / cm². 2 More preferably, it is 0.01 to 1 J / cm 2 Further preferably, it is 0.05–0.5 J / cm. 2 The pulse width (irradiation time) is preferably 0.01 to 1 × 10⁻⁶. 9 Picosecond, more preferably 0.1 to 1×10 7 Picosecond, further preferably 1 to 1×10 5 Picosecond. The pulse frequency is preferably 0.1–10000 Hz, more preferably 1–1000 Hz, and even more preferably 1–100 Hz. The number of irradiation pulses is preferably 1–30,000,000.

[0057] By using such a LIFT device, at the boundary between the substrate 11 and the anisotropic conductive adhesive layer 12, which has been irradiated with a laser, a shock wave is generated in the anisotropic conductive adhesive layer 12, causing multiple individual pieces 12a to be peeled off from the substrate 11 and moved toward the wiring substrate 20. This allows the multiple individual pieces 12a to land at predetermined positions on the wiring substrate 20. This transfer method is called laser lift-off, and for example, utilizes a laser-based ablation method. Therefore, the individual pieces 12a of the anisotropic conductive adhesive layer 12 can be transferred and arranged on the wiring substrate 20 with high precision and efficiency, thereby reducing cycle time.

[0058] The reaction rate of the individual sheets 12a of the anisotropic conductive adhesive layer 12 after the transfer process (A) is preferably 25% or less, more preferably 20% or less, and even more preferably 15% or less. By ensuring that the reaction rate of the individual sheets 12a is 25% or less, the light-emitting element can be thermo-pressed in the mounting process (B). The reaction rate can be determined, for example, using FT-IR.

[0059] [Installation Procedure (B)]

[0060] Figure 3 It is a schematic cross-sectional view showing a configuration in which light-emitting elements are mounted on a single piece of material arranged at specified positions on a wiring substrate. For example... Figure 3 As shown, in the mounting process (B), light-emitting elements 30 are mounted on single pieces 12a arranged at predetermined positions on the wiring substrate 20.

[0061] The light-emitting element 30 includes a main body 31, a first conductivity type electrode 32, and a second conductivity type electrode 33, having a horizontal structure in which the first conductivity type electrode 32 and the second conductivity type electrode 33 are disposed on the same side. The main body 31 includes, for example, a first conductivity type cladding layer made of n-GaN, and, for example, an In... xAl y Ga 1-x-y The active layer, composed of an N-layer, and the second conductivity cladding, for example, composed of p-GaN, have a so-called double heterostructure. A first conductivity electrode 32 is formed on a portion of the first conductivity cladding through a passivation layer, and a second conductivity electrode 33 is formed on a portion of the second conductivity cladding. When a voltage is applied between the first conductivity electrode 32 and the second conductivity electrode 33, charge carriers concentrate in the active layer and generate light through recombination.

[0062] There are no particular limitations on the method for mounting the light-emitting element 30 on the wiring substrate 20. Examples include: directly transferring the light-emitting element 30 from the wafer substrate and placing it on the wiring substrate 20 using a laser lift-off (LLO) method; or transferring the light-emitting element 30 from the transfer substrate and placing it on the wiring substrate 20 using a transfer substrate with the light-emitting element 30 pre-bonded to it. As a method for thermo-pressing the light-emitting element 30 onto the wiring substrate 20, a known connection method used in anisotropic conductive films can be appropriately selected. Thus, even when the wiring substrate 20 is exposed without anisotropic conductive adhesive layers between the light-emitting elements 30, anisotropic connection of the light-emitting elements 30 can be achieved on the wiring substrate 20. Furthermore, by using the wiring substrate 20 as a light-transmitting substrate, superior light transmittance can be obtained compared to the case where anisotropic conductive films are bonded to the entire surface of the wiring substrate 20.

[0063] As explained above, according to the manufacturing method of the display device according to the first embodiment, by irradiation with a laser, the individual sheets 12a of the anisotropic conductive adhesive layer 12 can be transferred and arranged on the wiring substrate 20 with high precision and high efficiency, thus shortening the cycle time. In the above embodiment, a manufacturing method of a display device as a display is given as an example, but the technology is not limited thereto, and can also be applied to a manufacturing method of a light-emitting device as a light source.

[0064] [Modifications of the First Embodiment]

[0065] In the transfer process (A) of the first embodiment described above, as Figure 2 As shown, the anisotropic conductive adhesive layer 12 is arranged on the wiring substrate 21 in the form of multiple pixel units, one pixel unit, or sub-pixel units constituting one pixel, but is not limited to these. For example, it can be arranged in the form of electrode units.

[0066] Figure 4 This is a schematic cross-sectional view showing the state in which monolithic anisotropic conductive adhesive layers are transferred onto a wiring substrate according to their electrode positions by irradiating the substrate side with a laser. Figure 5It is a schematic cross-sectional view showing the state of the light-emitting element mounted on a single chip arranged in electrode units on a wiring substrate.

[0067] like Figure 4 As shown, in the transfer process (A), for the first electrode 22 and the second electrode 23 corresponding to, for example, the first conductive electrode 32 on the p side and the second conductive electrode 33 on the n side of the light-emitting element 30, respectively, the first single piece 14 and the second single piece 15 are transferred, as shown. Figure 5 As shown, in the mounting process (B), the light-emitting element 30 can be mounted on a single piece of the wiring substrate 20 arranged in electrode units. This improves the transparency of the display device.

[0068] [Second Implementation]

[0069] The manufacturing method of the display device according to the second embodiment includes the following steps: a transfer step in which an anisotropic conductive adhesive layer disposed on a laser-transmissive substrate is placed opposite light-emitting elements arranged on a transfer substrate, and a laser is irradiated from the substrate side to transfer a single sheet of the anisotropic conductive adhesive layer onto the light-emitting elements arranged on the transfer substrate; a re-transfer step in which the light-emitting elements with the transferred single sheet are re-transferred onto a wiring substrate; and a mounting step in which light-emitting elements arranged at predetermined positions on the wiring substrate are mounted single sheets. By irradiating with a laser, single sheets of the anisotropic conductive adhesive layer can be transferred and arranged with high precision and high efficiency, thus shortening the cycle time.

[0070] The following is for reference Figures 6-9 The following steps will be described: a transfer process (A1) in which a monolithic anisotropic conductive adhesive layer is transferred onto light-emitting elements arranged on a transfer substrate; a re-transfer process (A2) in which the light-emitting elements with the monolithic layer are transferred onto a wiring substrate; and a mounting process (BB) in which light-emitting elements arranged at predetermined positions on a wiring substrate are mounted monolithically. It should be noted that the same reference numerals are used for components identical to those in the first embodiment, and descriptions are omitted.

[0071] [Transfer process (A1)]

[0072] Figure 6 It is a schematic cross-sectional view showing the state in which the anisotropic conductive adhesive layer disposed on the substrate is opposite to the light-emitting elements arranged on the transfer substrate. Figure 7 This is a schematic cross-sectional view showing an anisotropic conductive adhesive layer disposed on a substrate. For example... Figure 6 As shown, firstly, in the transfer process (A1), the anisotropic conductive adhesive layer substrate 10 is positioned opposite the transfer substrate 40.

[0073] The transfer substrate 40 has a substrate 41 and light-emitting elements 30 arranged on the substrate 41.

[0074] The substrate 41 is appropriately selected according to the transfer method of the re-transfer process (A2) described later. For example, when using a transfer method that utilizes laser-based ablation, the substrate 41 only needs to be transmissive to the laser, and quartz glass with high transmittance across the entire wavelength range is preferred. In addition, for example, when the transfer substrate 40 is attached to the wiring substrate 20 to transfer the light-emitting element 30, a silicone layer may be provided.

[0075] In the transfer process (A1), similar to the first embodiment described above, a laser-based ablation transfer method, such as laser stripping, can be used. When using ablation, such as... Figure 7 As shown, preferably, there are no conductive particles in the region X of the anisotropic conductive adhesive layer 12, which is 0 to 0.05 μm thick along the thickness direction from the side on which the substrate 11 is disposed.

[0076] A strong ablation effect exists in a region X of 0 to 0.05 μm along the thickness direction from the side of the anisotropic conductive adhesive layer 12 where the substrate 11 is disposed. Therefore, it is preferable that conductive particles are not present in this region X. In other words, it is preferable that all conductive particles are present in the portion of the anisotropic conductive adhesive layer other than the aforementioned region X, without any spillage. Here, the state in which conductive particles are not present in a certain region refers not only to the state in which conductive particles are not present in their entirety, but also to the state in which only a portion of conductive particles are not present in that region.

[0077] From the viewpoint of the yield of the anisotropic conductive adhesive layer, when conductive particles are mixed into region X, the number of conductive particles mixed into region X is preferably 5% or less of the total number of conductive particles contained in the anisotropic conductive adhesive layer, more preferably 1% or less.

[0078] Here, the thickness t of region X of the anisotropic conductive adhesive layer 12 can be set to 0 to 0.05 μm along the thickness direction from the side where the substrate 11 is disposed. In order to more reliably suppress the deterioration of conductive particles caused by ablation, this thickness t is set to 0 to 0.1 μm, more preferably 0 to 0.15 μm, and particularly preferably 0 to 0.2 μm. It is preferable that there are no conductive particles in this region. Similarly, in other words, it is preferable that all conductive particles are present without overflow in the portion of the anisotropic conductive adhesive layer other than these regions. In addition, similarly from the viewpoint of the yield of the anisotropic conductive adhesive layer, when conductive particles are mixed in these regions, the number of conductive particles mixed in the regions is preferably 5% or less, more preferably 1% or less, of the total number of conductive particles contained in the anisotropic conductive adhesive layer.

[0079] Furthermore, to improve the ablation resistance of the conductive particles, the metal constituting the conductive particles is preferably composed of a metal containing a metal with a melting point of 1400°C or higher. From the perspective of availability, the upper limit of the melting point is preferably around 3500°C. From the same viewpoint, the metal constituting the conductive particles preferably contains nickel, palladium, or ruthenium.

[0080] When using metal-coated resin particles obtained by coating the surface of the aforementioned resin particles with metal, or metal-coated inorganic particles obtained by coating the surface of inorganic particles with metal, in order to minimize the impact of ablation on the resin particles or inorganic particles, it is preferable to set the coating thickness formed by the metal to be 0.08 μm or more, more preferably 0.1 μm or more, particularly preferably 0.15 μm or more, and most preferably 0.2 μm or more. The upper limit of this coating thickness depends on the diameter of the conductive particles, and is preferably about 20% of the diameter of the conductive particles or about 0.5 μm.

[0081] Such anisotropic conductive adhesive layer is applicable not only to the second embodiment, but also to the first embodiment or its variations and other embodiments.

[0082] Figure 8 This is a schematic cross-sectional view showing the state in which an anisotropic conductive adhesive layer is monolithically transferred onto light-emitting elements arranged on a transfer substrate by irradiating a laser from the substrate side. For example... Figure 8 As shown, in the transfer process (A1), a laser is irradiated from the substrate 11 side to transfer individual sheets 16 of the anisotropic conductive adhesive layer 12 to a predetermined position on the wiring substrate 21 and arrange them. A laser is irradiated from the substrate 11 side to transfer individual sheets 16 of the anisotropic conductive adhesive layer 12 onto the light-emitting elements 30 arranged on the transfer substrate.

[0083] Similar to the first embodiment described above, a LIFT device can be used, for example, in the transfer of the individual sheets 16 of the anisotropic conductive adhesive layer 12. By using the LIFT device, a shock wave is generated at the interface between the substrate 11 and the anisotropic conductive adhesive layer 12, which has been irradiated with laser light, causing multiple individual sheets 16 to be peeled off from the substrate 11 and moved toward the light-emitting elements 30 arranged on the transfer substrate. This allows the individual sheets 16 to land on the light-emitting elements 30 with high precision, thereby shortening the cycle time.

[0084] [Re-transfer process (A2)]

[0085] Figure 9 This is a schematic cross-sectional view showing the process of transferring a single-piece light-emitting element onto a wiring substrate. For example... Figure 9As shown, in the re-transfer process (A2), the light-emitting element 30 with the single piece 16 transferred is re-transferred onto the wiring substrate. There is no particular limitation on the re-transfer method. For example, the following methods can be listed: directly transferring the light-emitting element 30 with the single piece 16 transferred from the transfer substrate 40 and placing it on the wiring substrate 20 by laser lift-off (LLO method); or using a transfer substrate with the light-emitting element 30 with the single piece 16 transferred beforehand to transfer the light-emitting element 30 from the transfer substrate 40 and placing it on the wiring substrate 20.

[0086] Furthermore, in the re-transfer process (A2), it is preferable to transfer the light-emitting element 30 using sub-pixel units that constitute one pixel. This allows for the adaptation of light-emitting element arrays ranging from high PPI (Pixels Per Inch) to low PPI.

[0087] [Installation Procedure (BB)]

[0088] In the mounting process (BB), light-emitting elements 30 are mounted at predetermined positions on the wiring substrate 20 via a single piece 16. The state of the mounted light-emitting elements 30 is similar to... Figure 3 Similarly, as a method for mounting the light-emitting element 30 on the wiring substrate 20, a known bonding method, such as thermoforming, used in anisotropic conductive films can be appropriately selected. This allows for anisotropic bonding of the light-emitting element 30 onto the wiring substrate 20 without anisotropic conductive adhesive layers between the light-emitting elements 30, thus exposing the wiring substrate 20. Furthermore, by making the wiring substrate 20 a light-transmitting substrate, superior light transmittance can be obtained compared to the case where anisotropic conductive films are adhered to the entire surface of the wiring substrate 20.

[0089] As explained above, according to the manufacturing method of the display device according to the second embodiment, by irradiation with a laser, the individual pieces 16 of the anisotropic conductive adhesive layer 12 can be transferred and arranged on the light-emitting element 30 with high precision and high efficiency, thereby shortening the cycle time.

[0090] [Modifications of the Second Embodiment]

[0091] In the transfer process (A1) of the second embodiment described above, as follows: Figure 8 As shown, a single sheet 16 of the anisotropic conductive adhesive layer 12 is transferred onto the light-emitting element 30, but this is not the only method. For example, single sheets of the anisotropic conductive adhesive layer can be transferred onto the light-emitting element according to electrode units. That is, the first single sheet and the second single sheet can be transferred onto, for example, the first conductive electrode 32 on the p-side and the second conductive electrode 33 on the n-side of the light-emitting element 30, respectively. This improves the transparency of the display device.

[0092] Example 2. Example 3

[0093] In this embodiment, an anisotropic conductive adhesive layer disposed on quartz glass is positioned opposite the plain glass. A laser is irradiated from the substrate side to transfer individual sheets of the anisotropic conductive adhesive layer to predetermined positions on the plain glass, and these sheets are then arranged. The arrangement of the individual sheets on the plain glass is then visually evaluated under a metal microscope. It should be noted that this embodiment is not limited to these specific details.

[0094] Fabrication of anisotropic conductive adhesive layer

[0095] An anisotropic conductive adhesive layer substrate with a 4μm thick anisotropic conductive adhesive layer on quartz glass was fabricated by laminating an anisotropic conductive adhesive layer with conductive particles of an average particle size of 2.2μm onto quartz glass. The adhesive for the anisotropic conductive adhesive layer was a mixture of 42 parts by weight of phenoxy resin (trade name: PKHH, manufactured by Ba Chemical Industry Co., Ltd.), 40 parts by weight of high-purity bisphenol A epoxy resin (trade name: YL-980, manufactured by Mitsubishi Chemical Corporation), 10 parts by weight of hydrophobic silica (trade name: R202, manufactured by Aerosil Corporation of Japan), 3 parts by weight of acrylic rubber (trade name: SG80H, manufactured by Nagase ChemteX Co., Ltd.), and 5 parts by weight of cationic polymerization initiator (trade name: SI-60L, manufactured by Sanshin Chemical Industry Co., Ltd.). The mixture was coated onto a 50μm thick PET film and dried to form the resin layer. Using the method described in Japanese Patent No. 6187665, conductive particles (average particle size 2.2 μm, resin core metal-coated microparticles, Ni plating thickness 0.2 μm, manufactured by Sekisui Chemicals Co., Ltd.) are arranged in a resin layer, such that one interface of the resin layer is approximately aligned with the conductive particles. In a top view of the anisotropic conductive adhesive layer, the orderly arrangement of the conductive particles is defined as a hexagonal lattice arrangement where the distance between the conductive particles is twice the particle size.

[0096] [Transfer of anisotropic conductive adhesive layer]

[0097] Using a LIFT apparatus (MT-30C200), a monolithic anisotropic conductive adhesive layer is transferred onto a plain glass substrate. As described above, the LIFT apparatus includes: a telescope that parallelizes a pulsed laser beam emitted from a laser device; a shaping optics system that shapes the spatial intensity distribution of the pulsed laser beam passing through the telescope to a uniform state; a mask that allows the pulsed laser beam shaped by the shaping optics system to pass through a predetermined pattern; a field-directing lens located between the shaping optics system and the mask; and a projection lens that reduces and projects the laser beam passing through the mask pattern onto a donor substrate. The anisotropic conductive adhesive layer substrate, serving as the donor substrate, is held on a donor stage, and the plain glass substrate, serving as the recipient substrate, is held on a recipient stage. The distance between the anisotropic conductive adhesive layer and the plain glass substrate is set to 100 μm.

[0098] The laser device uses an excimer laser with an oscillation wavelength of 248 nm. The laser pulse energy is 600 J, and the flux is 150 J / cm². 2 The pulse width (irradiation time) is 30,000 picoseconds, the pulse frequency is 0.01 kHz, and the irradiation pulse number for each small ACF piece is 1 pulse. The pulse energy of the laser irradiating the interface between the anisotropic conductive adhesive layer and the substrate is 0.001–2 J, and the flux is 0.001–2 J / cm². 2 The pulse width (irradiation time) is 0.01 to 1×10⁻⁶. 9 Picosecond lasers have a pulse frequency of 0.1–10,000 Hz and a pulse count of 1–30,000,000.

[0099] The mask employs a pattern of windows of a specified size arranged at a specified interval, so that the projection of the anisotropic conductive adhesive layer of the donor substrate and the boundary between the anisotropic conductive adhesive layer and the quartz glass forms a laser arrangement of 30μm in the longitudinal direction and 40μm in the transverse direction with a longitudinal spacing of 120μm and a transverse spacing of 160μm.

[0100] [Evaluation of the transfer]

[0101] The reactivity of a single anisotropic conductive adhesive layer arranged on a plain glass substrate was measured and found to be 17.4%. The reactivity was determined by FT-IR based on the reduction rate of epoxy groups in the single anisotropic conductive adhesive layer. Specifically, it was obtained by measuring the infrared absorption spectrum at 914 cm⁻¹. -1 The absorption was measured to determine how much the epoxy groups in the wafer before transfer were reduced by the laser transfer.

[0102] Figure 10 These are microscopic images of a single sheet of metal showing anisotropic conductive adhesive layers arranged on a plain glass substrate. Figure 11 yes Figure 10 A magnified image of the metal microscope photograph shown. (Example) Figure 10 and Figure 11 As shown, it can be confirmed that the individual sheets of the anisotropic conductive adhesive layer are transferred onto the plain glass according to the mask pattern. That is, it can be seen that by laser irradiation, the individual sheets of the anisotropic conductive adhesive layer can be transferred and arranged with high precision and high efficiency, thereby shortening the cycle time.

[0103] The embodiments of the present invention have been described in detail above. On the other hand, if the present invention is described from a different viewpoint, it becomes (1) to (29) and (U1) to (U18) as described below.

[0104] (1) A method for manufacturing a display device, comprising the following steps:

[0105] In the transfer process, an anisotropic conductive adhesive layer disposed on a laser-transmissive substrate is positioned opposite a wiring substrate, and a laser is irradiated from the substrate side to transfer individual sheets of the anisotropic conductive adhesive layer to predetermined positions on the wiring substrate and arrange them accordingly; and

[0106] In the installation process, light-emitting elements are installed on a single piece arranged at a specified position on the aforementioned wiring substrate.

[0107] (2)(1) The method for manufacturing the display device, wherein, in the above-mentioned transfer process, the individual sheets of the above-mentioned anisotropic conductive adhesive layer are arranged in a pixel unit.

[0108] (3)(1) The method for manufacturing the display device, wherein, in the above-mentioned transfer process, the individual sheets of the above-mentioned anisotropic conductive adhesive layer are arranged in sub-pixel units constituting one pixel.

[0109] (4)(1) The method for manufacturing the display device, wherein, in the above-mentioned transfer process, the single sheet of the above-mentioned anisotropic conductive adhesive layer is arranged in a plurality of pixel units.

[0110] (5)(1) The method for manufacturing a display device, wherein, in the above-mentioned transfer process, the individual sheets of the above-mentioned anisotropic conductive adhesive layer are arranged according to the electrode units of the above-mentioned light-emitting element.

[0111] The method for manufacturing a display device according to any one of (6)(1) to (5), wherein the distance between the individual pieces arranged at a predetermined position on the wiring substrate is 3 μm or more.

[0112] The method for manufacturing a display device according to any one of (7)(1) to (6), wherein the reaction rate of a single piece after the above-mentioned transfer process is 25% or less.

[0113] The method for manufacturing a display device according to any one of (8)(1) to (7), wherein,

[0114] The wavelength of the aforementioned laser is 180nm to 360nm.

[0115] The aforementioned anisotropic conductive adhesive layer contains a resin with a maximum absorption wavelength of 180nm to 360nm.

[0116] The method for manufacturing a display device according to any one of (9)(1) to (8), wherein the anisotropic conductive adhesive layer contains conductive particles.

[0117] The method for manufacturing a display device according to any one of (10)(1) to (9) wherein the anisotropic conductive adhesive layer is formed by arranging the conductive particles along the surface direction.

[0118] The method for manufacturing a display device as described in (11), (9) or (10) wherein the conductive particles are not present in the region of the anisotropic conductive adhesive layer in the thickness direction of 0 to 0.05 μm from the side on which the substrate is disposed.

[0119] The method for manufacturing a display device according to any one of (12), (9) to (11), wherein the conductive particles are metal-coated resin particles obtained by applying a metal coating to the surface of metal-coated resin particles, or metal-coated inorganic particles obtained by applying a metal coating to the surface of metal-coated resin inorganic particles.

[0120] The coating thickness formed by the aforementioned metal is 0.15 μm or more.

[0121] The method for manufacturing a display device according to any one of (13), (9) to (12), wherein the metal constituting the conductive particles comprises a metal with a melting point of 1400°C or higher.

[0122] (14) A method for manufacturing a display device, comprising the following steps:

[0123] In the transfer process, an anisotropic conductive adhesive layer disposed on a substrate that is transmissive to laser is placed opposite to light-emitting elements arranged on a transfer substrate, and a laser is irradiated from the substrate side to transfer a single piece of the anisotropic conductive adhesive layer onto the light-emitting elements arranged on the transfer substrate.

[0124] The re-transfer process involves transferring the light-emitting element, on which the aforementioned single piece was transferred, onto the aforementioned wiring substrate; and

[0125] The installation process involves mounting the light-emitting elements, which are arranged in predetermined positions on the wiring substrate using the aforementioned single-piece mounting.

[0126] (15)(14) The method for manufacturing a display device, wherein, in the above-mentioned transfer process, a single piece of the above-mentioned anisotropic conductive adhesive layer is transferred onto the above-mentioned light-emitting element according to the electrode unit.

[0127] The method for manufacturing a display device as described in (16), (14) or (15) wherein, in the above-mentioned re-transfer process, the light-emitting element is transferred in sub-pixel units constituting one pixel.

[0128] (17) A method for manufacturing a wiring substrate with an anisotropic conductive adhesive layer, comprising the following steps: placing an anisotropic conductive adhesive layer disposed on a substrate opposite to the wiring substrate, and irradiating the substrate side with a laser to transfer a single piece of the anisotropic conductive adhesive layer to a predetermined position on the wiring substrate.

[0129] (18) A method for manufacturing a light-emitting element with an anisotropic conductive adhesive layer, comprising a transfer process: the anisotropic conductive adhesive layer disposed on a substrate is positioned opposite to light-emitting elements arranged on a transfer substrate, and a laser is irradiated from the substrate side to transfer a single piece of the anisotropic conductive adhesive layer onto the light-emitting elements arranged on the transfer substrate.

[0130] (19) A film-like anisotropic conductive adhesive layer used for laser-based transfer.

[0131] (20)(19) The film-like anisotropic conductive adhesive layer contains conductive particles.

[0132] (21) (20) The film-like anisotropic conductive adhesive layer, wherein the conductive particles are not present in the region from the substrate side provided during the laser-based transfer with a thickness direction of 0 to 0.05 μm.

[0133] The anisotropic conductive adhesive layer of film described in (22), (20), or (21) wherein the conductive particles are metal-coated resin particles obtained by applying metal to the surface of metal-coated resin particles, or metal-coated inorganic particles obtained by applying metal to the surface of metal-coated resin inorganic particles.

[0134] The coating thickness formed by the aforementioned metal is 0.15 μm.

[0135] The film-like anisotropic conductive adhesive layer described in any one of (23), (20) to (22), wherein the metal constituting the conductive particles comprises a metal with a melting point of 1400°C or higher.

[0136] The film-like anisotropic conductive adhesive layer described in any one of (24), (20) to (23), wherein the metal constituting the conductive particles comprises nickel, palladium or ruthenium.

[0137] (25) A substrate having an anisotropic conductive adhesive layer laminated thereon for laser-based transfer.

[0138] (26) Application of anisotropic conductive adhesive layer in anisotropic conductive adhesive layer for laser lift transfer.

[0139] (27) Application of anisotropic conductive adhesive layer in manufacturing anisotropic conductive adhesive layer for laser lift transfer.

[0140] (28) Application of anisotropic conductive adhesive layers in the manufacture of substrates having anisotropic conductive adhesive layers laminated for laser-based exfoliation transfer.

[0141] (29) Application of anisotropic conductive adhesive layer in laser ablation.

[0142] (U1) A manufacturing system for a display device, comprising: a transfer mechanism that, by irradiating a laser from the substrate side onto a wiring substrate, an anisotropic conductive adhesive layer disposed on a laser-transmissive substrate, transfers individual sheets of the anisotropic conductive adhesive layer to predetermined positions on the wiring substrate and arranging them thereon; and

[0143] The mounting mechanism mounts light-emitting elements on a single piece arranged at a predetermined position on the aforementioned wiring substrate.

[0144] (U2)(U1) The manufacturing system for the display device, wherein, in the transfer mechanism, the individual sheets of the anisotropic conductive adhesive layer are arranged in a pixel unit.

[0145] (U3)(U1) The manufacturing system for the display device, wherein, in the transfer mechanism, the individual sheets of the anisotropic conductive adhesive layer are arranged in sub-pixel units constituting one pixel.

[0146] (U4)(U1) The manufacturing system for the display device, wherein, in the transfer mechanism, the individual sheets of the anisotropic conductive adhesive layer are arranged in a plurality of pixel units.

[0147] (U5)(U1) The manufacturing system for the display device, wherein, in the transfer mechanism, the individual sheets of the anisotropic conductive adhesive layer are arranged according to the electrode units of the light-emitting element.

[0148] The manufacturing system of the display device according to any one of (U6), (U1) to (U5), wherein the distance between the individual pieces arranged at a predetermined position on the wiring substrate is 3 μm or more.

[0149] The manufacturing system for the display device according to any one of (U7), (U1) to (U6), wherein the reaction rate of the single piece after transfer based on the transfer mechanism is 25% or less.

[0150] A manufacturing system for a display device according to any one of (U8), (U1) to (U7), wherein,

[0151] The wavelength of the aforementioned laser is 180nm to 360nm.

[0152] The aforementioned anisotropic conductive adhesive layer contains a resin with a maximum absorption wavelength of 180nm to 360nm.

[0153] The manufacturing system of the display device according to any one of (U9), (U1) to (U8), wherein the anisotropic conductive adhesive layer contains conductive particles.

[0154] The manufacturing system for the display device described in (U10)(U9) wherein the anisotropic conductive adhesive layer is formed by arranging the conductive particles along the surface direction.

[0155] The manufacturing system for the display device described in (U11), (U9) or (U10) wherein the conductive particles are not present in the region of the anisotropic conductive adhesive layer in the thickness direction of 0 to 0.05 μm from the side on which the substrate is disposed.

[0156] The manufacturing system for the display device according to any one of (U12), (U9) to (U11), wherein the conductive particles are metal-coated resin particles obtained by coating the surface of metal-coated resin particles, or metal-coated inorganic particles obtained by coating the surface of metal-coated inorganic particles.

[0157] The coating thickness formed by the aforementioned metal is 0.15 μm or more.

[0158] The manufacturing system of the display device according to any one of (U13), (U9) to (U12), wherein the metal constituting the conductive particles comprises a metal with a melting point of 1400°C or higher.

[0159] (U14) A manufacturing system for a display device, comprising:

[0160] The transfer mechanism arranges an anisotropic conductive adhesive layer disposed on a laser-transmitting substrate and light-emitting elements arranged on a transfer substrate opposite each other, and irradiates the substrate side with a laser to transfer a single piece of the anisotropic conductive adhesive layer onto the light-emitting elements arranged on the transfer substrate.

[0161] The re-transfer mechanism re-transfers the light-emitting element, on which the aforementioned single piece was transferred, onto the aforementioned wiring substrate; and

[0162] The mounting mechanism is used to mount light-emitting elements that are arranged at predetermined positions on the wiring substrate using the aforementioned single-piece mounting mechanism.

[0163] (U15)(U14) The manufacturing system for the display device, wherein, in the transfer mechanism, a single sheet of the anisotropic conductive adhesive layer is transferred onto the light-emitting element in electrode units.

[0164] The manufacturing system for the display device described in (U16), (U14) or (U15), wherein, in the re-transfer mechanism, the light-emitting element is transferred in sub-pixel units constituting one pixel.

[0165] (U17) A manufacturing system for a wiring substrate with an anisotropic conductive adhesive layer, having a mechanism that, when the anisotropic conductive adhesive layer disposed on a substrate is facing the wiring substrate, irradiates the substrate side with a laser to transfer a single piece of the anisotropic conductive adhesive layer to a predetermined position on the wiring substrate.

[0166] (U18) A manufacturing system for a light-emitting element with an anisotropic conductive adhesive layer, comprising a transfer mechanism that irradiates a light-emitting element arranged on a transfer substrate with the anisotropic conductive adhesive layer disposed on a substrate facing the light-emitting element arranged on the transfer substrate by irradiating the substrate with a laser to transfer a single piece of the anisotropic conductive adhesive layer onto the light-emitting element arranged on the transfer substrate.

[0167] The constituent elements in the above-described multiple embodiments can be subdivided, and the subdivided constituent elements can be introduced individually or in combination into (1) to (29) and (U1) to (U18) above.

[0168] Symbol Explanation

[0169] 10: Substrate; 11: Substrate material; 12: Anisotropic conductive adhesive layer; 12a: Monolith; 13: Conductive particle; 20: Wiring substrate; 21: Substrate material; 22: First electrode; 23: Second electrode; 30: Light-emitting element; 31, 32: First conductive electrode; 33: Second conductive electrode; 40: Transfer substrate; 41: Substrate material.

Claims

1. A method for manufacturing a display device, comprising the following steps: In the transfer process, an anisotropic conductive adhesive layer disposed on a laser-transmissive substrate is positioned opposite a wiring substrate. A laser is irradiated from the side of the substrate away from the anisotropic conductive adhesive layer, thereby transferring individual sheets of the anisotropic conductive adhesive layer to predetermined positions on the wiring substrate and arranging them accordingly. In the installation process, light-emitting elements are installed on a single piece arranged at a specified position on the aforementioned wiring substrate.

2. The method for manufacturing the display device according to claim 1, wherein, In the above transfer process, the individual sheets of the anisotropic conductive adhesive layer are arranged in a pixel unit.

3. The method for manufacturing the display device according to claim 1, wherein, In the above transfer process, the individual sheets of the anisotropic conductive adhesive layer are arranged in sub-pixel units that constitute one pixel.

4. The method for manufacturing the display device according to claim 1, wherein, In the above transfer process, the individual sheets of the anisotropic conductive adhesive layer are arranged in multiple pixel units.

5. The method for manufacturing the display device according to claim 1, wherein, In the above transfer process, the individual sheets of the above anisotropic conductive adhesive layer are arranged according to the electrode units of the above light-emitting element.

6. A method for manufacturing a display device according to any one of claims 1 to 5, wherein, The distance between the individual pieces arranged at the specified positions on the above wiring substrate is 3. μ m or more.

7. A method for manufacturing a display device according to any one of claims 1 to 5, wherein, The reaction rate of a single sheet after the above transfer process is less than 25%. The reaction rate is obtained by using Fourier transform infrared spectroscopy based on the reduction rate of epoxy groups in the single sheet.

8. A method for manufacturing a display device according to any one of claims 1 to 5, wherein, The wavelength of the aforementioned laser is 180nm to 360nm. The aforementioned anisotropic conductive adhesive layer contains a resin with a maximum absorption wavelength of 180nm to 360nm.

9. A method for manufacturing a display device according to any one of claims 1 to 5, wherein, The aforementioned anisotropic conductive adhesive layer contains conductive particles.

10. The method of manufacturing the display device according to claim 9, wherein, The anisotropic conductive adhesive layer is formed by arranging the conductive particles neatly along the surface direction.

11. The method of manufacturing the display device according to claim 9, wherein, The anisotropic conductive adhesive layer extends from the side where the substrate is disposed along its thickness direction from 0 to 0.05 mm. μ The aforementioned conductive particles do not exist in region m.

12. The method of manufacturing the display device according to claim 9, wherein, The aforementioned conductive particles are either metal-coated resin particles obtained by coating the surface of resin particles with metal, or metal-coated inorganic particles obtained by coating the surface of inorganic particles with metal. The coating thickness formed by the aforementioned metal is 0.

15. μ m or more.

13. The method of manufacturing the display device according to claim 9, wherein, The metals constituting the above-mentioned conductive particles include metals with a melting point of 1400°C or higher.

14. A method for manufacturing a display device, comprising the following steps: In the transfer process, an anisotropic conductive adhesive layer disposed on a substrate that is transmissive to laser is placed opposite to light-emitting elements arranged on a transfer substrate. Laser is irradiated from the side of the substrate away from the anisotropic conductive adhesive layer to transfer a single piece of the anisotropic conductive adhesive layer onto the light-emitting elements arranged on the transfer substrate. The re-transfer process involves transferring the light-emitting element, on which the aforementioned single piece was transferred, onto a wiring substrate; and The installation process involves mounting the light-emitting elements, which are arranged in predetermined positions on the wiring substrate using the aforementioned single-piece mounting.

15. The method of manufacturing the display device according to claim 14, wherein, In the above transfer process, the single sheet of the anisotropic conductive adhesive layer is transferred onto the light-emitting element according to the electrode unit.

16. A method for manufacturing the display device according to claim 14 or 15, wherein, In the above-mentioned re-transfer process, the light-emitting element is transferred according to the sub-pixel units that constitute one pixel.

Images