Manufacturing method of repair unit, repair unit and repair method of MLED display lamp panel

Abstract

The invention discloses a manufacturing method of a repair unit, the repair unit and a repair method of an MLED display lamp panel, and belongs to the field of MLED display. The problems that an MLED display lamp panel is difficult to maintain, the maintenance cost is high, and the application range of a maintenance method is small are solved. In order to solve the technical problem, the technical scheme adopted by the invention is as follows: the manufacturing method of the repair unit comprises the following steps of: providing a decomposable first carrier, transferring a large amount of first LED chips onto the first carrier by using an FOB process, and adhering light-emitting surfaces of the first LED chips onto the first carrier; covering the electrode surface of the first LED chip subjected to mass transfer with a second protective film, wherein the second protective film, the first LED chip and the first carrier form a layered structure; the repair unit is manufactured by the manufacturing method of the repair unit. The repair method of the MLED display lamp panel is a repair method of the MLED display lamp panel based on the repair unit. The MLED display lamp panel repair method is applied to MLED display lamp panel repair.

Description

[0001] A manufacturing method of a repair unit, a repair unit and a repair method of an MLED display light board Technical Field

[0002] The invention provides a manufacturing method of a repair unit, a repair unit and a repair method of an MLED display lamp board, belonging to the technical field of MLED display. Background Art

[0003] With the development of MLED technology and its wide application in consumer electronics, commercial display screens and other fields, how to repair defective products efficiently and non-destructively has become one of the key issues in improving product yield. For the rework of MLED display light boards after the film protective layer is adhered to them, the current rework methods may inevitably affect the ink color consistency of the reworked MLED display light boards, or completely remove the film protective layer and damage the normally working LED chips, increasing the repair cost.

[0004] Based on this, the Chinese invention patent (CN116154049A) provides a method for manufacturing a display module, a display module and a rework method. In order to facilitate subsequent maintenance, a display module is provided, and the success rate and efficiency of rework are improved by changing the structure of the display module. However, it covers the light-emitting surface of the light-emitting chip with a thin film protective layer and a protective film. When rework is required, the protective film is torn off, the thin film protective layer is cut, and the pad is heated to remove the faulty light-emitting chip. However, this method undoubtedly increases the manufacturing cost of the display module, and the rework method is complicated and has a certain scope of application. Summary of the invention

[0005] In order to solve the technical problems of difficult maintenance, high maintenance cost and small application scope of the maintenance method of the MLED display light board after the film pasting process, the present invention proposes a method for manufacturing a rework unit, a rework unit and a rework method for the MLED display light board. The purpose is to set a rework unit that can be mass-produced, so that the MLED display light board can be accurately, quickly and efficiently repaired based on the rework unit, thereby greatly improving the application scope of the MLED display light board.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for manufacturing a rework unit, comprising the following steps: Step S11, providing a decomposable first carrier, wherein the decomposition temperature of the first carrier is lower than the temperature required for soldering the rework unit to the pad of the PCB; Step S12: using the FOB process to transfer a large amount of the first LED chips to the first carrier, and adhering the light-emitting surface of the first LED chips to the first carrier; Step S13: Covering the electrode surface of the first LED chip after mass transfer with a second protective film, wherein the second protective film, the first LED chip and the first carrier form a layered structure.

[0007] Furthermore, the decomposition temperature of the first carrier ranges from 150°C to 250°C.

[0008] Furthermore, the first carrier is made of polyimide material or polycarbonate material.

[0009] Furthermore, the second protective film is made of polyimide material or polyethylene terephthalate material.

[0010] Furthermore, the second protective film has a thickness ranging from 1 μm to 10 μm.

[0011] A rework unit is manufactured by the manufacturing method of the rework unit.

[0012] A method for repairing an MLED display light board comprises the following steps: Step S21, preparing the above-mentioned rework unit; Step S22, using high-precision automatic detection equipment to detect the coordinate value of the faulty LED chip on the MLED display lamp board, and then determine the repaired LED chip and the repair area that need to be repaired; Step S23, covering the thin film protective layer in the normal working area of ​​the MLED display light board with a first protective film; Step S24, removing the thin film protective layer in the repair area to expose the PCB pads and remove the repaired LED chip; Step S25, cutting the rework unit according to the shape and size of the rework area and the type of the LED chip to be reworked to obtain a second rework unit, wherein the shape and size of the second rework unit are adapted to the shape and size of the rework area; Step S26, flip-chip soldering the second rework unit to the rework area after the rework LED chip is removed, so that the second rework unit is electrically connected to the PCB board, and testing the display effect, during which the first LED chip of the second rework unit is exposed; Step S27, filling a transparent insulating thermosetting material around the first LED chip of the second rework unit, and covering the surface of the first LED chip of the second rework unit with a heat-sensitive material; Step S28, softening the heat-sensitive material and making it plastic so that it fits the film protective layer in the normal working area; Step S29, testing the optical and electrical properties of the repaired MLED display lamp board.

[0013] Furthermore, the rework unit in step S21 is the rework unit as claimed in claim 5.

[0014] Further, the repaired LED chip includes a faulty LED chip and other light-emitting LED chips that form the same pixel point together with the faulty LED chip, or the repaired LED chip is a plurality of adjacent faulty LED chips with different pixel points; The repair area includes the repaired LED chip, the thin film protective layer covering the repaired LED chip, and the area where the repaired LED chip is located on the PCB pad; The normal working area includes the normally emitting LED chips except the repaired LED chips, the thin film protection layer covering the normally emitting LED chips, and the area where the normally emitting LED chips are located on the PCB board pads.

[0015] Furthermore, the device for cutting the repair unit in step S25 is an ultraviolet laser with a wavelength of 355 nm, a power range of 1 W to 5 W, and a cutting speed range of 10 mm / s to 50 mm / s.

[0016] Further, the heat-sensitive material in step S27 is a thermosetting resin material, the softening temperature range of which is 80° C. to 120° C., and the hardening temperature range of which is 150° C. to 200° C.; The filling thickness of the transparent insulating thermosetting material ranges from 10 μm to 50 μm.

[0017] The beneficial effects of the present invention compared with the prior art are as follows: 1. The first carrier of the present invention has high temperature decomposition performance, low pollution and adhesion, and can be decomposed at high temperature. The decomposed product will not pollute the first LED chip and the PCB board pad, which is convenient for subsequent treatment; and it will not affect the display effect and transmittance of the first LED chip, while ensuring the integrity of the first LED chip during the transfer process; 2. The second protective film of the repair unit of the present invention can prevent damage to the electrode of the first LED chip during the repair process, and can ensure the cleanliness when applying solder paste to the electrode of the first LED chip; 3. The present invention uses the FOB process to transfer a large number of first LED chips to the first carrier, which can effectively improve the repair efficiency and repair accuracy during large-area repair and reduce production costs; 4. The present invention covers the first protective film around the repair area of ​​the MLED display light board and partially cuts the repair area of ​​the MLED display light board using laser cutting technology, thereby effectively avoiding damage to the nano dimming film in the normal working area of ​​the MLED display light board during the repair process, and protecting the original structure of the normal working area of ​​the MLED display light board; 5. The arrangement of the repair unit, the arrangement of the first protective film, and the arrangement of flip-chip welding the second repair unit to the fault position after the LED chip for repair is removed, combined with advanced process technologies such as laser cutting technology, greatly improves the speed, accuracy and success rate of MLED display light board repair, reduces production costs, improves the quality of MLED display light boards, and enhances user experience; 6. The MLED display light board rework method based on the rework unit of the present invention can greatly expand the applicable scope of MLED display light board rework and save rework costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 It is a structural schematic diagram of the MLED display light board of the present invention; Figure 2 A schematic diagram showing a process of transferring a first LED chip in bulk onto a first carrier; Figure 3 It is a structural schematic diagram of a rework unit of the present invention; Figure 4 It is a schematic diagram showing the process of the cutting and repairing unit of the present invention; Figure 5 A schematic diagram of the structure of the second rework unit of the present invention cooperating with the rework area; Figure 6 This is a structural schematic diagram of the MLED display lamp board after repair according to the present invention; Figure 7 It is a flow chart of the repair method of the MLED display lamp board of the present invention; In the figure: 1 is a PCB board, 2 is a first LED chip, 3 is a thin film protective layer, 4 is a blue film, 5 is a ejector pin, 6 is a normal light-emitting LED chip, 7 is a first carrier, 8 is a second protective film, 9 is an ultraviolet laser, 10 is a second rework unit, 11 is a rework unit, 13 is solder paste, 14 is a transparent insulating thermosetting material, and 15 is a heat-sensitive material. DETAILED DESCRIPTION

[0019] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate relative positions or positional relationships, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0021] like Figures 1 to 7 As shown, the present invention provides a method for manufacturing a rework unit, comprising the following steps: Step S11, providing a first carrier 7, the first carrier 7 has high temperature decomposition performance, low pollution and adhesion, that is, the first carrier 7 can be completely decomposed within its decomposition temperature range, the decomposition product is non-toxic and harmless, and will not pollute the first LED chip 2 and the PCB board 1 pad, and the decomposition temperature of the first carrier 7 is lower than the temperature required to solder the unit 11 to be repaired to the pad of the PCB board 1 to be repaired, so as to ensure that the first carrier 7 can be completely decomposed during the process of soldering the repair unit 11 to the pad of the PCB board 1 to be repaired. Specifically, the decomposition temperature range of the first carrier 7 is 150°C to 250°C, and it can be made of polymer materials such as polyimide or polycarbonate; Step S12, use the FOB process to transfer the first LED chip 2 in bulk to the first carrier 7, and adhere the light-emitting surface of the first LED chip 2 to the first carrier 7. The adhesion of the first carrier 7 can ensure that the first LED chip 2 will not fall off during the mass transfer process; specifically, use the ejector pin 5 to transfer the first LED chip 2 adhered to the blue film 4 to the first carrier 7.

[0022] Step S13, the electrode surface of the first LED chip 2 after mass transfer is covered with a second protective film 8, the second protective film 8 has good heat resistance and chemical stability, and the thickness is determined to ensure that the heat dissipation performance and optical performance of the chip are not affected. Specifically, the second protective film 8 is made of polyimide material or polyethylene terephthalate material, with a thickness ranging from 1 μm to 10 μm. The second protective film 8 is used to prevent damage to the electrode of the first LED chip 2 and ensure cleanliness when applying solder paste 13. The first carrier 7, the first LED chip 2 and the second protective film 8 form a layered structure.

[0023] The present invention also provides a repair unit, which is manufactured by the manufacturing method of the repair unit.

[0024] The present invention also provides a method for repairing an MLED display lamp board, which is characterized by comprising the following steps: Step S21, preparing a rework unit 11, wherein the rework unit 11 adopts the above-mentioned reverse repair unit.

[0025] Step S22: Use high-precision automatic detection equipment to detect the coordinate values ​​of the faulty LED chips on the MLED display lamp board, and then determine the LED chips to be repaired, the repair area, and the fault type. In this embodiment, the high-precision automatic detection equipment uses an automatic optical inspection instrument AOI (Automated Optical Inspection).

[0026] Specifically, the repaired LED chip includes a faulty LED chip and other light-emitting LED chips that form the same pixel point together with the faulty LED chip, or the repaired LED chip is a plurality of faulty LED chips of different adjacent pixels; The repair area includes the repaired LED chip, the thin film protection layer 3 covering the repaired LED chip, and the area where the repaired LED chip is located on the soldering pad of the PCB board 1; Use a microscope to detect the fault type of the faulty LED chip and determine whether the faulty LED chip has a short circuit problem.

[0027] Step S23 , covering the thin film protection layer 3 in the normal working area of ​​the MLED display lamp board with a first protection film to prevent the thin film protection layer 3 in the normal working area of ​​the MLED display lamp board from being damaged during the repair process.

[0028] Specifically, the normal working area includes the normally emitting LED chips 6 except the repaired LED chips, the thin film protection layer 3 covering the normally emitting LED chips 6 , and the area where the normally emitting LED chips 6 are located on the pads of the PCB board 1 .

[0029] Step S24, remove the film protective layer 3 in the repair area, expose the pad of the PCB board 1, and remove the repaired LED chip. Specifically, use laser cutting technology to remove the adhesive layer of the nano dimming film covering the fault area, so that the position of the repaired LED chip on the pad of the PCB board 1 is exposed, and remove the repaired LED chip in the repair area by decrystalline equipment or manual method.

[0030] Step S25, cutting the rework unit 11 according to the shape and size of the rework area and the type of the LED chip to be reworked, to obtain a second rework unit 10, the shape and size of the second rework unit 10 are adapted to the shape and size of the rework area, and the number of the second rework units 10 is one or more. The device for cutting the rework unit 11 is an ultraviolet laser 9. In this embodiment, the wavelength of the ultraviolet laser 9 is 355nm, the power range is 1W to 5W, and the cutting speed range is 10mm / s to 50mm / s. The laser cutting path is set according to the shape and size of the rework area. Those skilled in the art may also adjust the laser according to the type and thickness of the first carrier 7. power , frequency, scanning speed and other parameters to ensure the cutting accuracy and efficiency.

[0031] Step S26, flip-chip soldering the second rework unit 10 to the rework area after the rework LED chip is removed, so that the second rework unit 10 is electrically connected to the PCB board 1, and the display effect is tested. During this process, the first LED chip 2 of the second rework unit 10 is exposed.

[0032] Specifically, the second protective film 8 covering the second rework unit 10 is torn off to expose the electrode of the first LED chip 2 on the second rework unit 10, and a proper amount of solder paste 13 is applied on the electrode of the first LED chip 2. The selection of the solder paste 13 should take into account its compatibility with the solder pad and the quality of subsequent welding. Then, a high-precision automatic placement machine is used to accurately place the second rework unit 10 after the solder paste 13 is applied on the solder pad of the PCB board 1 where the reworked LED chip is removed, so that the electrode of the first LED chip 2 of the second rework unit 10 is in contact with the solder pad of the PCB board 1. Finally, a high-precision welding device is used to weld the second rework unit 10 to the rework area where the reworked LED chip is removed. During this process, the first carrier 7 is completely decomposed to expose the first LED chip 2 of the second rework unit 10, and its decomposition products will not pollute the solder pad of the PCB board 1 and the first LED chip 2, and will not generate toxic gases.

[0033] In this embodiment, a lead-free solder paste 13 is used, and the amount of solder applied is 0.03 mg, which is evenly applied on the electrode of the first LED chip 2 of the second rework unit 10 .

[0034] In this embodiment, the high-precision welding equipment is a laser welding machine or a hot air blower. When using a laser welding machine for welding, the heating temperature range is preferably 200°C to 300°C, and the heating time is 1 second to 5 seconds; when using a hot air blower for welding, the heating temperature range is preferably 250°C to 350°C, and the heating time is 2 seconds to 10 seconds.

[0035] More specifically, a high-precision test device is used to accurately measure and calibrate the display effect of the repaired MLED display light board. The accuracy of the high-precision test device is ±5μm, ensuring that the display effect of the second repair unit 10 is consistent with the display effect of the normal working area around it. The high-precision test device uses a spectrometer or a colorimeter.

[0036] Step S27, fill transparent insulating thermosetting material 14 around the first LED chip 2 of the second repair unit 10 to enhance mechanical strength and waterproof performance, and cover the light-emitting surface of the first LED chip 2 of the second repair unit 10 with a thermosensitive material 15, the thermosensitive material 15 is a brittle solid material at room temperature, softens when heated to a certain temperature, and hardens after continued heating to form a good protective layer. In this embodiment, the transparent insulating thermosetting material 14 is preferably epoxy resin, silicone resin, epoxy molding compound (EMC), and the filling thickness ranges from 10μm to 50μm; the thermosensitive material 15 is preferably a thermosetting resin material, and its softening temperature ranges from 80℃ to 120℃, and the hardening temperature ranges from 150℃ to 200℃, such as epoxy resin-based, phenolic resin-based, polyurethane resin-based, unsaturated polyester resin-based, etc.

[0037] Step S28, smoothing the plasticity of the heat-sensitive material 15 when it is softened, so that it can be matched with the film protective layer 3 in the normal working area, ensuring that the surface of the MLED display light board is flat and smooth to avoid optical defects. The tool used in the smoothing plasticity step is preferably a flexible scraper or roller, and its operating temperature range is preferably 80°C to 120°C.

[0038] Step S29, testing the optical and electrical properties of the repaired MLED display lamp board.

[0039] In order to better understand the specific implementation process of the present invention, several specific embodiments are described in detail below with reference to the accompanying drawings.

[0040] Embodiment 1: When the repaired LED chip includes a faulty LED chip and other light-emitting LED chips that form the same pixel point with the faulty LED chip, that is, when a single LED chip is damaged, the repair method of the MLED display light board, this embodiment takes a single red LED chip as an example of a faulty LED chip.

[0041] When step S22 detects that the coordinate value of the MLED display light board where it is located is (123, 456), based on the coordinate value, determine that the repaired LED chip is the above-mentioned red faulty LED chip, and the blue LED chip and green LED chip that form the same pixel point with the red faulty LED chip; determine that the repair area includes the above-mentioned repaired LED chip, the thin film protective layer 3 covering the above-mentioned repaired LED chip, and the area where the repaired LED chip is located on the soldering pad of the PCB board 1; use a microscope to perform a detailed inspection to confirm that the repaired LED chip does have a short circuit problem.

[0042] A first protective film is covered on the nano dimming film of the normal light-emitting LED chip 6 in the normal working area, and then a 355 nm ultraviolet laser 9 is used with a power of 3 W and a cutting speed of 30 mm / s to accurately remove the nano dimming film in the above-mentioned repair area to expose the repaired LED chip, and a micro nozzle with a suction force of 1N is used to carefully remove the repaired LED chip. A microscope is used to assist in the operation to ensure that the normal light-emitting LED chip 6 in the surrounding normal working area is not damaged.

[0043] The rework unit 11 is cut according to the shape and size of the rework area and the type of the LED chip to be reworked to obtain a second rework unit 10 , and the shape and size of the second rework unit 10 are adapted to the shape and size of the rework area.

[0044] Tear off the second protective film 8 covering the second rework unit 10, use lead-free solder paste 13, with a tin amount of 0.03 mg, and evenly apply it on the electrodes of the reworked chip; use a high-precision automatic placement machine to accurately place the second rework unit 10 after applying the solder paste 13 on the pad of the PCB board 1 where the reworked LED chip is removed; use a 980nm laser welding machine to weld the second rework unit 10 to the rework area where the reworked LED chip is removed, the power of the laser welding machine is 15W, the heating time is 3 seconds, and the heating temperature is 250°C, to ensure that the solder joint is fully melted and a good electrical connection is formed. During this process, the first LED chip 2 of the second rework unit 10 is exposed; use a brightness and color measuring instrument to measure the brightness and color temperature of the pixel, adjust the brightness and color of the pixel according to the measurement results, and ensure that it is consistent with the display effect of other pixels.

[0045] A 20 μm thick layer of silicone is filled around the first LED chip 2 of the pixel, and then a layer of epoxy resin-based thermosensitive material 15 which softens at 80°C and hardens at 180°C is covered on its surface; a high-temperature resistant PTFE scraper is used to perform a smoothing operation at 100°C to ensure that the surface of the MLED display light board is flat and smooth, so that the final surface roughness is Ra<0.1 μm.

[0046] Embodiment 2: When the LED chips to be repaired are multiple adjacent faulty LED chips with different pixels, a method for repairing an MLED display light board is used. This embodiment takes the failure of three adjacent red LED chips, green LED chips and blue LED chips as an example.

[0047] When step S22 detects that the faulty LED chips are a red LED chip, a green LED chip and a blue LED chip at three adjacent different pixel points, it is confirmed that the coordinate values ​​of the faulty LED chips are (123, 456), (124, 456) and (125, 456) respectively. Based on the above coordinate values, it is confirmed that the repaired LED chips are the above three faulty LED chips, and the repair area is determined to include the above repaired LED chips, the thin film protective layer 3 covering the above repaired LED chips and the area where the repaired LED chips are located on the soldering pad of the PCB board 1. A detailed inspection is performed using a microscope to confirm that the repaired LED chip does have a short circuit problem.

[0048] A first protective film is covered on the nano dimming film of the normal light-emitting LED chip 6 in the normal working area, and then according to the coordinates (123, 456) and (125, 456), a 355 nm ultraviolet laser 9 with a power of 4 W and a cutting speed of 40 mm / s is used to accurately remove the back adhesive layer of the nano dimming film in the repair area surrounded by the above coordinates (123, 456) and (125, 456) at one time to expose the repaired LED chip, and micro tweezers are used to remove the three faulty LED chips of the repaired LED chip one by one, and a microscope is used to assist in the operation to ensure that other components are not damaged.

[0049] The rework unit 11 is cut according to the shape and size of the rework area and the type of the LED chip to be reworked to obtain a second rework unit 10 , and the shape and size of the second rework unit 10 are adapted to the shape and size of the rework area.

[0050] The remaining repair steps are the same as those in the first embodiment.

[0051] Embodiment 3: When a MLED display light board has defects in a large area due to production process problems, that is, the LED chips to be repaired are faulty LED chips with more than three adjacent pixels, a method for repairing the MLED display light board is used. This embodiment takes a repair area of ​​100mm×100mm as an example.

[0052] Use the automatic optical inspection device AOI to scan the entire MLED display light board to identify and record the coordinate values ​​and fault types of all faulty LED chips.

[0053] Since the repair area is large, a first protective film with a larger area can be used or a plurality of first protective films can be spliced ​​to cover the thin film protective layer 3 in the repair area. Use high-power laser equipment, such as a CO2 laser, to quickly remove the adhesive layer of the nano dimming film in the repair area to expose the repaired LED chip, and use automated equipment (such as a robotic arm) with a micro nozzle or pliers to efficiently remove the faulty LED chip in the repair area.

[0054] The rework unit 11 is cut by laser cutting technology according to the shape and size of the rework area and the type of LED chip to be reworked, so as to obtain a second rework unit 10, the shape and size of the second rework unit 10 being adapted to the shape and size of the rework area.

[0055] The remaining rework steps are consistent with those in Example 1. It should be noted that the solder paste 13-point coating head, patch speed, welding power, etc. are appropriately adjusted according to the size of the rework area.

[0056] Embodiment 4: When a rework area of ​​a certain MLED display light board has an irregular shape due to design reasons, for example, the shape of the rework area is a triangle, a circle, etc., a rework method of the MLED display light board.

[0057] When it is detected in step S22 that the repair area surrounded by the multiple faulty LED chips is of an irregular shape, an automatic optical inspection device AOI is used to identify and record the coordinate values ​​and fault types of all the faulty LED chips in the repair area.

[0058] The remaining rework steps are consistent with the rework steps in Example 1, but it should be noted that the shape and size of the first protective film, the laser scanning path, the solder paste 13-point coating head, the patch head and the smoothing tool are adjusted according to the shape and size of the irregular rework area.

[0059] The MLED display lamp board rework method of the present invention comprises the steps of confirming the rework area, protecting with film, removing glue with laser, removing crystals, cutting and trimming with laser, tinning, re-crystal filling, welding, testing and correction, packaging and smoothing, etc., which can quickly and accurately repair the MLED display lamp board and greatly improve the success rate of rework.

[0060] Regarding the specific structure of the present invention, it should be noted that the connection relationship between the various component modules adopted in the present invention is definite and feasible. Except for special instructions in the embodiments, the specific connection relationship can bring about corresponding technical effects, and solve the technical problems raised by the present invention without relying on the execution of corresponding software programs. The components, modules, models of specific components, the connection methods between each other, and the conventional use methods and expected technical effects brought about by the above-mentioned technical features, except for specific instructions, all belong to the disclosed contents in patents, journal articles, technical manuals, technical dictionaries, and textbooks that can be obtained by technical personnel in this field before the application date, or belong to the existing technologies such as conventional technologies and common knowledge in this field, and there is no need to elaborate, so that the technical solution provided in this case is clear, complete, and feasible, and the corresponding physical products can be reproduced or obtained according to the technical means.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for manufacturing a rework unit, characterized in that: The following steps are involved: Step S11, providing a decomposable first carrier (7), wherein the decomposition temperature of the first carrier (7) is lower than a temperature required for soldering the rework unit (11) to a soldering pad of the PCB board (1); Step S12: using the FOB process to transfer a large amount of the first LED chips (2) onto the first carrier (7), and adhering the light-emitting surface of the first LED chips (2) onto the first carrier (7); Step S13: Covering the electrode surface of the first LED chip (2) after the mass transfer with a second protective film (8), wherein the second protective film (8), the first LED chip (2) and the first carrier (7) form a layered structure.

2. The method for manufacturing a rework unit according to claim 1, characterized in that: The decomposition temperature of the first carrier (7) is in the range of 150°C to 250°C.

3. The method for manufacturing a rework unit according to claim 1, characterized in that: The first carrier (7) is made of a polyimide material or a polycarbonate material.

4. The method for manufacturing a rework unit according to claim 1, characterized in that: The second protective film (8) is made of polyimide material or polyethylene terephthalate material.

5. The method for manufacturing a rework unit according to claim 1, characterized in that: The thickness of the second protective film (8) ranges from 1 μm to 10 μm.

6. A rework unit, characterized in that: The rework unit is manufactured by the manufacturing method of the rework unit according to any one of claims 1 to 5.

7. A method for repairing an MLED display lamp board, characterized in that: The following steps are involved: Step S21, preparing the reverse repair unit (11) as claimed in claim 6; Step S22, using high-precision automatic detection equipment to detect the coordinate value of the faulty LED chip on the MLED display lamp board, and then determine the repaired LED chip and the repair area that need to be repaired; Step S23, covering the thin film protective layer (3) in the normal working area of ​​the MLED display light board with a first protective film; Step S24, removing the thin film protective layer (3) in the repair area, exposing the soldering pads of the PCB board (1), and removing the repaired LED chip; Step S25, cutting the rework unit (11) according to the shape and size of the rework area and the type of the LED chip to be reworked, to obtain a second rework unit (10), wherein the shape and size of the second rework unit (10) are adapted to the shape and size of the rework area; Step S26, flip-chip soldering the second rework unit (10) to the rework area after the rework LED chip is removed, so that the second rework unit (10) is electrically connected to the PCB board (1), and testing the display effect, during which the first LED chip (2) of the second rework unit (10) is exposed; Step S27, filling a transparent insulating thermosetting material (14) around the first LED chip (2) of the second rework unit (10), and covering the surface of the first LED chip (2) of the second rework unit (10) with a heat-sensitive material (15); Step S28, softening the heat-sensitive material (15) and making it plastic so that it can fit the thin film protective layer (3) in the normal working area; Step S29, testing the optical and electrical properties of the repaired MLED display lamp board.

8. A method for repairing an MLED display lamp board according to claim 7, characterized in that: The repaired LED chip includes a faulty LED chip and other light-emitting LED chips that form the same pixel point together with the faulty LED chip, or the repaired LED chip is a plurality of adjacent faulty LED chips with different pixel points; The repair area includes a repaired LED chip, a thin film protective layer (3) covering the repaired LED chip, and an area on a soldering pad of a PCB board (1) where the repaired LED chip is located; The normal working area comprises the normally emitting LED chips (6) excluding the repaired LED chips, the thin film protective layer (3) covering the normally emitting LED chips (6), and the area on the soldering pad of the PCB board (1) where the normally emitting LED chips (6) are located.

9. A method for repairing an MLED display lamp board according to claim 7, characterized in that: The device for cutting and repairing the unit (11) in step S25 is an ultraviolet laser (9) having a wavelength of 355 nm, a power range of 1 W to 5 W, and a cutting speed range of 10 mm / s to 50 mm / s.

10. The repair method of an MLED display lamp board according to claim 7, characterized in that: The heat-sensitive material (15) in step S27 is a thermosetting resin material, the softening temperature range of which is 80°C to 120°C, and the hardening temperature range of which is 150°C to 200°C; The filling thickness of the transparent insulating thermosetting material (14) ranges from 10 μm to 50 μm.

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