Self-assembly method of LED display device

Abstract

A self-assembly method for an LED display device includes the following steps: S1 providing a driver board, disposing a plurality of solder pads on the front of the driver board, each of which is provided with a first metal; S2 heating the driver board to a first temperature range above the melting point of the first metal, causing the first metal to melt and form liquid metal sticking points; S3 applying a large number of LED devices provided with soft magnetic layers to the front side of the driver board; S4 disposing a first magnetic adsorption member on the back side of the driver board, adsorbing the LED devices to the front side of the driver board, causing the soldering surfaces of the LED devices to wet and adhere to the liquid metal sticking points and be captured by the soldering pads; S5 removing LED devices from the driver board that are not captured by the soldering pads; S6 lowering the temperature of the driver board to solidify the liquid metal sticking points and form welds, thereby producing the LED display device. The present invention can not only significantly improve the manufacturing efficiency of LED array devices, meeting the requirements of mass production, but also effectively reduce manufacturing costs.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor displays, and in particular to a self-assembly method for an LED display device. Background Art

[0002] The application of third-generation semiconductors to displays is a key development direction in display technology. LED displays, which use semiconductor light-emitting devices (LEDs) as display units or pixels mounted on a display driver board, offer excellent display performance (high brightness, high contrast, high color gamut, wide viewing angle, and fast response) with low energy consumption and a long lifespan. Whether used as direct-view displays or as zoned backlights for liquid crystal displays, they are considered a more advanced display technology than traditional liquid crystal displays and organic light-emitting displays.

[0003] Currently, such LED displays typically include oversized LED curtain walls with display unit spacing reaching centimeters. While these displays are easy to manufacture, the fact that each display unit requires soldering an LED bead results in low manufacturing efficiency and very high costs. These displays also include Mini-LED and Micro-LED displays. Mini-LED displays feature millimeter-level display spacing. Currently, Mini-LEDs can be used for direct display or as local dimming backlights for LCDs. These displays typically utilize chip bonding technology, where LED chips are individually bonded to display unit locations. However, the sheer number of LED chips required results in low manufacturing efficiency and high costs. Micro-LED displays are LED display devices with display unit pitch below a millimeter. Due to the small pitch and huge number of display units, mass transfer technology is generally required to transfer the LED light-emitting body from the LED growth wafer (such as the epitaxial board used to grow LEDs) to the display unit positions of the display driver board. Currently, mass transfer technology is not yet mature. Although it can be transferred batch by batch through a transfer head, its efficiency is still low and the defect rate is high, which cannot meet the requirements of mass production.

[0004] Therefore, there is currently no efficient technology for manufacturing such LED display devices, which cannot efficiently set a large number of LEDs at the display unit positions of the display driver board to reduce the manufacturing difficulty and cost of such displays. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a self-assembly method for an LED display device, which can not only significantly improve the manufacturing efficiency of the LED array device and meet the requirements of mass production, but also effectively reduce the manufacturing cost of the LED array device. The technical solution adopted is as follows:

[0006] A self-assembly method for an LED display device, characterized by comprising the following steps:

[0007] S1. Provide a driving board, and set a plurality of pads on the front surface of the driving board, each pad being provided with a first metal;

[0008] S2, heating the temperature of the driving board to a first temperature range higher than the melting point of the first metal, so that the first metal on each pad melts to form liquid metal sticky points;

[0009] S3. Apply a large number of LED devices provided with a soft magnetic layer to the side close to the front of the driver board, each LED device including a first electrode surface and a second electrode surface facing away from each other, the first electrode surface being a non-metallic light emitting surface, and the second electrode surface being a welding surface;

[0010] S4. A first magnetic adsorption component is provided on a side close to the back of the driver board, with its magnetic end close to the back of the driver board. The magnetic field generated by the first magnetic adsorption component transmits through the driver board to generate an adsorption force on the soft magnetic layers of a large number of the LED devices, adsorbing these LED devices to the front of the driver board, and causing the soldering surfaces of at least some of the LED devices to be wetted and adhered to the liquid metal sticking points on some of the soldering pads so as to be captured by the soldering pads, automatically forming an assembled state with the light-emitting surfaces facing outward.

[0011] S5. Clear the LED devices on the driver board that are not captured by the pads;

[0012] S6. Lowering the temperature of the driving board to a second temperature range lower than the melting point of the first metal, so that the liquid metal sticking point solidifies to form a weld between the soaked and adhered LED device and the soldering pad, thereby manufacturing the LED display device.

[0013] In the self-assembly method of the above-mentioned LED display device, steps S1 and S2 form liquid metal sticking points of multiple solder pads on the first plate surface of the driver board. The liquid metal sticking points are formed by a molten first metal attached to the solder pads. The molten first metal has a very high surface tension (generally, the surface tension of liquid metal is about 10 times that of ordinary liquids). At the same time, its wettability to non-metals is extremely low, while its wettability to metals (such as the second metal) is extremely high, thereby giving it extremely strong adhesion selectivity. In step S3, the LED device used is a vertical structure LED with a soft magnetic layer, so that in step S4, by providing a first magnetic adsorption member on the back of the driver board, the LED device can be tightly attracted to the front of the driver board. For LED devices that fall on the solder pads, they are adsorbed into the liquid metal sticking points of the first metal, so that the soldering surface of the LED device contacts and wets the liquid metal sticking points, thereby greatly increasing the probability that the LED device will eventually be captured by the solder pad. After the LED device is captured by the solder pad, based on the infiltration and spread of the liquid metal sticky points on the solder pad, the LED device and the solder pad can be aligned and straightened by surface tension, automatically forming an assembled state with the light-emitting surface facing outward; in S6, the temperature of the driving board is lowered to the second temperature range, which can solidify the liquid metal sticky points and form a weld between the assembled LED device and the solder pad, thereby producing the LED array device.

[0014] The driving board can be a printed circuit board (including a flexible circuit board), a glass board or a plastic board (such as a polyimide film) with a display driving circuit (such as a static driving circuit, a dynamic driving circuit or an active driving circuit); the solder pads are generally preset on the driving board and form an array, for example: they can be pre-arranged according to the pixel array.

[0015] The first electrode surface and the second electrode surface of the LED device are facing away from each other. This type of LED device is generally called a vertical structure LED device. A vertical structure LED device is an LED device or chip in which the electrodes (P pole and N pole) are located on two opposite sides of the device. In this specification, the light-emitting surface and the welding surface of the LED device correspond to the P pole and N pole (or N pole and P pole) of the LED, respectively. The welding surface can be a metal (such as gold, silver, copper, zinc, iron) or alloy film surface that is easily wetted by the first metal. The LED device can be an LED device whose semiconductor layer is GaAs, GaP, SiC, or GaN. Generally, the LED devices are all LED devices with the same luminous color or semiconductor material, such as GaN blue light LED.

[0016] As a preferred embodiment of the present invention, the first metal is a low-melting-point metal. Specifically, the first metal can be a pure metal or an alloy thereof having a melting point below 400°C. For example, the first metal can be tin, bismuth, indium or an alloy thereof, such as a tin-lead alloy, a tin-indium alloy, a tin-silver alloy, a tin-lead-silver alloy, a tin-copper alloy, a tin-silver-copper alloy, a tin-bismuth alloy or a tin-bismuth-silver alloy; the first temperature zone can be a temperature range of about 50°C slightly higher than the melting point of the first metal. Specifically, the first metal can be a tin-bismuth alloy having a melting point below 150°C, and the first temperature range can be set at 150-200°C. As a result, it can be heated in a short time and generally will not affect structures such as the driver board and LED devices.

[0017] The first metal can be pre-deposited on the pad by printing, coating, plating, spraying, etc. The first metal can be pre-melted and infiltrated to fully cover the pad, or pre-deposited on the pad in the form of a paste (such as solder paste), or attached to the pad by a combination of plating and patterning. The amount of the first metal on the pad is sufficient to form sufficient infiltration coverage on the pad and the second electrode surface; however, to prevent the melted first metal from falling off the pad and to ensure the correct angle of the LED device, the amount of the first metal should not be excessive. Preferably, the thickness or height of the first metal does not exceed half the width of the pad.

[0018] To prevent the soft magnetic layer from affecting light emission, as a preferred embodiment of the present invention, the soft magnetic layer is disposed on the inner side of the soldering surface of the LED device. Generally, the soft magnetic layer can be a soft magnetic metal (such as iron, nickel, or manganese) film layer placed beneath the soldering surface of the LED device. Under normal conditions, the soft magnetic layer has no magnetic field (soft magnetic metals, i.e., metals with low coercivity and high magnetic permeability, are generally demagnetized and have no magnetic field), preventing adjacent LED devices from attracting each other and causing agglomeration. The structure of this vertically structured LED device with a soft magnetic layer and its manufacturing method can be found in the Chinese invention patent specification with authorization publication number CN108682725A, entitled "A Vertically Structured LED Device and Its Manufacturing Method."

[0019] The first magnetic attraction member can be a permanent magnet or an electromagnet, with its magnetic end facing the back of the driver board. The first magnetic attraction member can be a single magnet or multiple magnets, thereby improving the self-assembly efficiency of the LED device. For example, the first magnetic attraction member is a row of magnets, or an array of multiple magnets. The magnetic end of the first magnetic attraction member can be one pole of the magnet (such as the north pole or the south pole), or two or more poles of the magnet (when the magnet is a multi-pole magnet).

[0020] As a preferred embodiment of the present invention, in step S4, the first magnetic attraction member is moved so that the magnetic end of the first magnetic attraction member is translated relative to the back surface of the driver board (i.e., moves parallel to the back surface of the driver board), so that the LED device is attracted to different positions on the front surface of the driver board. In this way, the LED device is captured by the solder pads at different positions on the front surface of the driver board.

[0021] As another preferred embodiment of the present invention, in step S4, the driver board is moved so that the back side of the driver board moves relative to the magnetic end of the first magnetic attraction member, so that the LED device is attracted to different positions on the front side of the driver board. As a result, the LED device is captured by the soldering pads at different positions on the front side of the driver board.

[0022] As a preferred embodiment of the present invention, the first magnetic member is a bar magnet having an elongated magnetic end parallel to the driver plate. The first magnetic member can be fixed to a movable mechanism (particularly a translation mechanism) to change the relative position (e.g., vertical distance or horizontal position) of the first magnetic member and the driver plate. This allows the first magnetic member to be swept horizontally relative to the driver plate, thereby improving the self-assembly efficiency of the LED device.

[0023] As another preferred embodiment of the present invention, the first magnetic attraction member utilizes a first electromagnet. In step S4, the first electromagnet is energized to generate a magnetic field, which transmits through the driver board to generate an attraction force on the soft magnetic layers of a large number of LED devices, thereby adsorbing these LED devices to the front surface of the driver board. In step S5, the first electromagnet is de-energized, allowing the LED devices not captured by the soldering pads to be released from the front surface of the driver board, thereby removing the LED devices not captured by the soldering pads from the driver board. The first magnetic attraction member utilizes the first electromagnet, which reduces mechanical structure and provides a faster response, thereby facilitating more efficient self-assembly of LED devices.

[0024] As a preferred embodiment of the present invention, in step S5, the magnetic end of the first magnetic attraction member is moved away from the back of the driver board, so that the LED devices not captured by the soldering pads are released from the front of the driver board. In this way, the LED devices not captured by the soldering pads on the driver board are removed, leaving only the LED devices captured by the soldering pads.

[0025] As a preferred embodiment of the present invention, in step S3, the front side of the driver board is facing downward, a collection plate is provided below the front side of the driver board, and a large number of LED devices are applied between the front side of the driver board and the collection plate; in step S4, the first magnetic adsorption member is located directly above the driver board with its magnetic end facing the back side of the driver board; in step S5, the magnetic end of the first magnetic adsorption member is moved away from the back side of the driver board, so that the LED devices not captured by the soldering pad are released from the front side of the driver board by their own gravity and fall onto the collection plate. The collection plate can be a part (such as the bottom) of a container used to store LED devices and to heat hot liquid.

[0026] As a further preferred embodiment of the present invention, steps S4 and S5 are repeated to reattach the LED devices that have fallen onto the collection plate to the front of the driver plate, allowing more LED devices to be captured by the soldering pads. This allows uncaptured LED devices to be recaptured by the soldering pads. By repeating steps S4 and S5, the LED devices undergo multiple adsorption processes, allowing each soldering pad to capture as many LED devices as possible, thereby increasing the success rate of LED device self-assembly and achieving full LED device self-assembly.

[0027] As a further preferred embodiment of the present invention, before repeating steps S4 and S5, the relative positions of the driver board and the magnetic end of the first magnetic attraction member are changed. This allows LED devices to be captured by solder pads at different positions on the driver board. In particular, all solder pad positions on the first soldering surface can be traversed to ensure that all solder pads on the driver board capture LED devices.

[0028] As another preferred embodiment of the present invention, a collection plate is provided on the front side of the driver board; in step S3, a large number of the LED devices are applied between the front side of the driver board and the collection plate, and a second magnetic adsorption member is provided on the side of the collection plate away from the driver board; in step S5, the magnetic end of the first magnetic adsorption member is moved away from the back side of the driver board, and the magnetic end of the second magnetic adsorption member is moved closer to the back side of the collection plate, so that the LED devices not captured by the soldering pad are released from the front side of the driver board and adsorbed onto the collection plate by the second magnetic adsorption member. The collection plate can be a portion (such as the bottom) of a container for storing and heating hot liquid; the second magnetic adsorption member can adopt the same configuration as the first magnetic adsorption member, with the magnetic ends of the first magnetic adsorption member and the second magnetic adsorption member corresponding to each other in shape and position, such as the first magnetic adsorption member and the second magnetic adsorption member being bar magnets of the same size and shape, with their magnetic ends facing each other. In this way, through the adsorption of the second magnetic adsorption member, the LED devices on the driver board that are not captured by the soldering pad can be more thoroughly removed, leaving only the LED devices captured by the soldering pad.

[0029] As a further preferred embodiment of the present invention, the second magnetic attraction member utilizes a second electromagnet; in step S4, the second electromagnet is de-energized; in step S5, the second electromagnet is further energized, causing the LED devices not captured by the soldering pads to be released from the front of the driver board and attracted to the collection plate by the second electromagnet. The use of the second electromagnet as the second magnetic attraction member allows for more convenient and efficient control of its magnetic field, enabling high-frequency switching of the magnetic field to generate magnetic oscillations.

[0030] As a further preferred embodiment of the present invention, steps S4 and S5 are repeated to re-adsorb the LED devices that have fallen onto the collection plate onto the front surface of the driver board, allowing more LED devices to be captured by the soldering pads. This allows the LED devices on the collection plate to be re-adsorbed onto the front surface of the driver board, with the possibility of their soldering surfaces re-contacting and wetting the first metal of some of the soldering pads, thereby being captured by the soldering pads. Furthermore, by repeating steps S4 and S5, the LED devices undergo multiple adsorption processes, allowing each soldering pad to capture as many LED devices as possible, completing sufficient LED device self-assembly and improving the success rate of LED device self-assembly.

[0031] As a further preferred embodiment of the present invention, before repeating steps S4 and S5, the relative positions of the driver board and the magnetic end of the first magnetic attraction member are changed. This allows LED devices to be captured by solder pads at different positions on the driver board. In particular, all solder pad positions on the first soldering surface can be traversed to ensure that all solder pads on the driver board capture LED devices.

[0032] As a preferred embodiment of the present invention, in steps S2-S5, the driver board and LED devices are both immersed in a hot liquid. The hot liquid can be a liquid with a high boiling point or vaporization temperature, such as paraffin oil or silicone oil, and is heated to a temperature exceeding the melting point of the first metal to maintain the temperature of the driver board. Thus, the hot liquid not only maintains the temperature of the LED device but also, due to the resistance of the liquid, slows the speed of the LED device, preventing damage to the LED device from high-speed collisions with the driver board, collector plate, or other LED devices under the influence of the magnetic field.

[0033] As a further preferred embodiment of the present invention, the hot liquid is composed of molten rosin, which not only has a high vaporization temperature but also can remove the oxide layer on the first metal and the second metal, thereby improving their wettability.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] The present invention can not only greatly improve the manufacturing efficiency of the LED array device and meet the requirements of mass production, but also effectively reduce the manufacturing cost of the LED array device. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of the structure of the driving board provided in step S1 of Example 1 of the preferred embodiment of the present invention.

[0037] Figure 2 It is a structural schematic diagram of the LED device provided in step S3 in Example 1 of the preferred embodiment of the present invention.

[0038] Figure 3 This is a schematic diagram of the process of automatically forming a state in which the light-emitting surface of the LED device faces outward when the LED device is captured by the soldering pad in step S4 of Example 1 of the preferred embodiment of the present invention.

[0039] Figure 4 1 is a process diagram of steps S3-S5 in Example 1 of a preferred embodiment of the present invention.

[0040] Figure 5 2 is a process diagram of steps S3 to S5 in Example 2 of a preferred embodiment of the present invention.

[0041] Figure 6 1 is a process diagram of steps S3-S5 in Example 3 of a preferred embodiment of the present invention.

[0042] Figure 7 It is a schematic diagram of the LED device and the soldering pad after being welded in Example 4 of the preferred embodiment of the invention. DETAILED DESCRIPTION

[0043] Example 1, as Figures 1-4 As shown, the self-assembly method of the LED display device includes the following steps:

[0044] S1. Provide a driving board 1, and set a plurality of pads 11 on the front surface of the driving board 1, each pad 11 being provided with a first metal 12;

[0045] S2, heating the driving board 1 to a first temperature range higher than the melting point of the first metal 12, so that the first metal 12 on each pad 11 melts to form liquid metal sticky points 120;

[0046] S3. Apply a large number of LED devices 2 provided with a soft magnetic layer 20 to the side close to the front of the driving board 1. Each LED device 2 includes a first electrode surface 21 and a second electrode surface 22 facing away from each other. The first electrode surface 21 is a non-metallic light emitting surface, and the second electrode surface 22 is a welding surface.

[0047] S4. A first magnetic adsorption member 3 is provided on a side close to the back of the driver board 1, with its magnetic end close to the back of the driver board 1. The magnetic field generated by the first magnetic adsorption member 3 transmits through the driver board 1 to generate an adsorption force on the soft magnetic layers 20 of a large number of LED devices 2, adsorbing these LED devices 2 to the front of the driver board 1, so that the soldering surfaces of at least some of the LED devices 2 are infiltrated and adhered to the liquid metal adhesive points 120 on some of the soldering pads 11, so as to be captured by the soldering pads 11, and automatically form an assembled state with the light-emitting surface facing outward;

[0048] S5, removing the LED devices 2 on the driving board 1 that are not captured by the pads 11, leaving only the LED devices 2 captured by the pads 11;

[0049] S6. Lower the temperature of the driving board 1 to a second temperature range lower than the melting point of the first metal 12, so that the liquid metal sticky points 120 solidify to form a weld between the soaked and adhered LED device 2 and the soldering pad 11, thereby manufacturing an LED display device.

[0050] In this embodiment, the driving board 1 is a printed circuit board with a display driving circuit (such as a static driving circuit, a dynamic driving circuit, or an active driving circuit); the pads 11 are preset on the driving board 1 and form an array.

[0051] In this embodiment, the first metal 12 is a low-melting-point metal. For example, the first metal 12 is a tin-bismuth alloy with a melting point below 150°C, and the first temperature range can be set between 150°C and 200°C. This allows for heating in a short period of time without generally affecting the driver board 1, LED device 2, and other structures. The first metal 12 can be pre-placed on the pad 11 by printing, coating, plating, spraying, or other methods. The first metal 12 can be pre-melted, infiltrated, and fully covered on the pad 11. Alternatively, the first metal 12 can be pre-placed on the pad 11 in the form of a paste (such as solder paste), or attached to the pad 11 by a combination of plating and patterning. The amount of first metal 12 on the pad 11 is sufficient to fully wet and cover the pad 11 and the second electrode surface 22. However, to prevent the melted first metal 12 from falling off the pad 11 and to ensure the proper alignment of the LED device 2, the amount of first metal 12 should be limited, and the thickness or height of the first metal 12 should not exceed half the width of the pad 11.

[0052] In this embodiment, LED device 2 is a vertically structured LED device. The light-emitting surface and soldering surface of LED device 2 correspond to the P-pole and N-pole (or N-pole and P-pole), respectively, of the LED. The soldering surface is a metal (such as gold, silver, copper, zinc, iron) or alloy thin film surface that is easily wetted by the first metal 12. LED device 2 is an LED device whose semiconductor layer 23 is GaAs, GaP, SiC, or GaN (such as a GaN blue LED).

[0053] To prevent the soft magnetic layer 20 from affecting light emission, in this embodiment, the soft magnetic layer 20 is disposed inside the second electrode surface 22 of the LED device 2. Specifically, the soft magnetic layer 20 is a film of a soft magnetic metal (such as iron, nickel, or manganese) disposed beneath the second electrode surface 22 of the LED device 2. Under normal conditions, the soft magnetic layer 20 is free of magnetic fields (soft magnetic metals, i.e., metals with low coercivity and high magnetic permeability, are generally demagnetized and free of magnetic fields). This prevents adjacent LED devices 2 from attracting each other and causing agglomeration. The structure and manufacturing method of this vertically structured LED device 2 equipped with a soft magnetic layer 20 can be found in the Chinese invention patent specification, entitled "A Vertically Structured LED Device and Its Manufacturing Method," with authorization publication number CN108682725B.

[0054] In this embodiment, in steps S2-S5, the driver board 1 and the LED device 2 are immersed in a hot liquid 50, which is composed of molten rosin. The hot liquid 50 is heated to a temperature exceeding the melting point of the first metal 12 to maintain the temperature of the driver board 1. The hot liquid 50 is composed of molten rosin, which not only has a high vaporization temperature but also can remove the oxide layer on the first metal 12 and the second metal, thereby improving its wettability. The hot liquid 50 can not only be used to maintain the temperature of the LED device 2, but also, based on the resistance of the liquid, can slow down the speed of the LED device 2, thereby preventing the LED device 2 from forming a high-speed collision with the driver board 1, the collecting plate 4 or other LED devices 2 under the action of the magnetic field, thereby preventing damage caused by the collision.

[0055] In this embodiment, the first magnetic attraction member 3 is a permanent magnet, and the magnetic ends of the first magnetic attraction member 3 are the north pole and the south pole of the permanent magnet, thereby improving the self-assembly efficiency of the LED device 2 .

[0056] In this embodiment, in step S3, the front side of the driving board 1 is facing downward and the back side is facing upward, a collecting plate 4 is provided below the front side of the driving board 1, and a large number of LED devices 2 are applied between the front side of the driving board 1 and the collecting plate 4; in step S4, the first magnetic adsorption component 3 is located directly above the driving board 1 and its magnetic end is facing the back side of the driving board 1; in step S5, the magnetic end of the first magnetic adsorption component 3 is moved away from the back side of the driving board 1, so that the LED devices 2 not captured by the soldering pad 11 are released from the front side of the driving board 1 due to their own gravity and fall onto the collecting plate 4; repeat steps S4-S5, the LED devices 2 that fall on the collecting plate 4 are re-adsorbed to the front side of the driving board 1, and the relative position of the driving board 1 and the magnetic end of the first magnetic adsorption component 3 is changed, so that more LED devices 2 are captured by the soldering pad 11. The collection plate 4 can be a part (such as the bottom) for storing LED devices and serving as a container for heating the hot liquid 50. By repeating the operations of steps S4-S5, the LED device 2 undergoes multiple adsorption processes, so that each soldering pad 11 can capture the LED device 2 as much as possible, thereby improving the success rate of self-assembly of the LED device 2, completing the full self-assembly of the LED device 2, and allowing the soldering pads 11 at different positions of the driving board 1 to capture the LED device 2, especially traversing all the positions of the soldering pads 11 on the second electrode surface 22, so that all the soldering pads 11 of the driving board 1 capture the LED device 2.

[0057] Example 2, reference Figure 5 , while other parts are the same as those in Example 1, the difference is that: in step S3, a second magnetic adsorption component 5 is provided on the lower side of the collecting plate 4; in step S4, before the magnetic end of the first magnetic adsorption component 3 is brought close to the back side of the driving board 1, the magnetic end of the second magnetic adsorption component 5 is moved away from the front side of the driving board 1; in step S5, the magnetic end of the first magnetic adsorption component 3 is moved away from the back side of the driving board 1, and the magnetic end of the second magnetic adsorption component 5 is brought close to the back side of the collecting plate 4, so that the LED devices 2 not captured by the soldering pad 11 are released from the front side of the driving board 1 and adsorbed onto the collecting plate 4 by the second magnetic adsorption component 5; before performing step S6, steps S4-S5 are repeated, and the LED devices 2 dropped on the collecting plate 4 are re-adsorbed onto the front side of the driving board 1, so that more LED devices 2 are captured by the soldering pad 11. As a result, the LED device 2 on the collection plate 4 is re-adsorbed onto the front of the driving board 1, and has the possibility of re-contacting the first metal 12 of part of the pad 11 with its welding surface and being wetted, thereby being captured by the pad 11; and by repeating the operations of step S4-step S5, the LED device 2 undergoes multiple adsorption processes, so that each pad 11 captures the LED device 2 as much as possible, completing the full self-assembly of the LED device 2, and improving the success rate of the self-assembly of the LED device 2.

[0058] In this embodiment, the second magnetic attraction member 5 utilizes the same permanent magnet as the first magnetic attraction member 3. The magnetic ends of the first magnetic attraction member 3 and the second magnetic attraction member 5 correspond in shape and position. Thus, the second magnetic attraction member 5 can more thoroughly remove the LED devices 2 on the driver board 1 that are not captured by the soldering pads 11, leaving only the LED devices 2 captured by the soldering pads 11.

[0059] Example 3, reference Figure 6 While all other aspects are identical to those of Example 2, the difference is that in this embodiment, the first magnetic attraction member 3 is a first electromagnet. In step S4, the first electromagnet is energized to generate a magnetic field, which transmits through the driver board 1 to generate an attraction force on the soft magnetic layers 20 of a large number of LED devices 2, thereby adsorbing these LED devices 2 to the front surface of the driver board 1. In step S5, the first electromagnet is de-energized, releasing the LED devices 2 not captured by the soldering pads 11 from the front surface of the driver board 1, thereby removing the LED devices 2 not captured by the soldering pads 11 from the driver board 1. The use of the first electromagnet as the first magnetic attraction member 3 reduces mechanical structure and provides a faster response, facilitating more efficient self-assembly of the LED devices 2.

[0060] In this embodiment, the second magnetic attraction member 5 is a second electromagnet. In step S4, the second electromagnet is de-energized. In step S5, the second electromagnet is also energized, causing the LED devices 2 not captured by the soldering pads 11 to be released from the front of the driver board 1 and attracted to the collection plate 4 by the second electromagnet. The use of the second electromagnet in the second magnetic attraction member 5 allows for more convenient and efficient control of its magnetic field, enabling high-frequency switching of the magnetic field to generate magnetic oscillations.

[0061] Example 4, reference Figure 7 , while other parts are the same as those in Example 1, the difference is that: in this embodiment, the size of the pad 11 is larger than the size of the LED device 2; in the step S4, multiple LED devices 2 are adhered to one pad 11, and the number of LED devices 2 adhered to different pads 11 can be the same or different.

[0062] In addition, it should be noted that the names of the various parts of the specific embodiments described in this specification may be different. Any equivalent or simple changes based on the structure, features, and principles of the patent concept of the present invention are included in the scope of protection of the patent of this invention. Those skilled in the art of the art to which the present invention relates may make various modifications, supplements, or replace the specific embodiments described in the present invention with similar methods. As long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they shall fall within the scope of protection of the present invention.

Claims

1. A self-assembly method for an LED display device, characterized in that The steps include: S1. Provide a driving board, and set a plurality of pads on the front surface of the driving board, each pad being provided with a first metal; S2, immersing the driving board in hot liquid having a temperature exceeding the melting point of the first metal, and heating the driving board to a first temperature range higher than the melting point of the first metal, so that the first metal on each pad melts to form liquid metal sticky points; S3. Place the front surface of the driver board downward, with a collecting plate provided below the front surface of the driver board. Apply a large number of LED devices provided with a soft magnetic layer between the front surface of the driver board and the collecting plate and immerse them in the hot liquid. Each LED device includes a first electrode surface and a second electrode surface facing away from each other. The first electrode surface is a non-metallic light emitting surface, and the second electrode surface is a welding surface. S4. A first magnetic adsorption component is disposed directly above the driver board, with the magnetic end of the first magnetic adsorption component facing the back of the driver board and close to the back of the driver board. The magnetic field generated by the first magnetic adsorption component transmits through the driver board to generate an adsorption force on the soft magnetic layers of a large number of the LED devices. The relative position of the driver board and the magnetic end of the first magnetic adsorption component is changed to adsorb the LED devices to different positions on the front of the driver board, so that the soldering surfaces of at least some of the LED devices are infiltrated and adhered to the liquid metal sticking points on some of the soldering pads so as to be captured by the soldering pads, automatically forming an assembled state with the light-emitting surfaces facing outward. S5. Move the magnetic end of the first magnetic attraction member away from the back of the driver board, so that the LED devices not captured by the soldering pads are released from the front of the driver board by their own gravity and fall onto the collection plate, thereby removing the LED devices not captured by the soldering pads from the driver board; S6. Lowering the temperature of the driving board to a second temperature range lower than the melting point of the first metal, so that the liquid metal sticking point solidifies to form a weld between the soaked and adhered LED device and the soldering pad, thereby manufacturing the LED display device.

2. The self-assembly method of an LED display device according to claim 1, wherein: The soft magnetic layer is arranged on the inner side of the soldering surface of the LED device.

3. The self-assembly method of an LED display device according to claim 1, wherein: Move the first magnetic attraction member or the driving plate to move the magnetic end of the first magnetic attraction member relative to the back side of the driving plate.

4. The self-assembly method of an LED display device according to claim 1, wherein: The first magnetic attraction component is a strip magnet having a long strip magnetic attraction end parallel to the driving plate.

5. The self-assembly method of an LED display device according to claim 1, wherein: The first magnetic adsorption component adopts a first electromagnet; in the step S4, the first electromagnet is energized to generate a magnetic field, and the magnetic field generates an adsorption force on the soft magnetic layers of a large number of LED devices through the driving board, thereby adsorbing these LED devices to the front of the driving board; in the step S5, the first electromagnet is de-energized, so that the LED devices not captured by the soldering pad are released from the front of the driving board, and the LED devices not captured by the soldering pad on the driving board are cleared.

6. The self-assembly method of an LED display device according to claim 1, wherein: In the step S5, the magnetic end of the first magnetic attraction member is moved away from the back of the driving board, so that the LED devices not captured by the soldering pads are released from the front of the driving board.

7. The self-assembly method of an LED display device according to claim 1, wherein: Before performing step S6, steps S4 to S5 are repeated to re-adsorb the LED devices dropped on the collecting plate onto the front of the driving plate, so that more LED devices are captured by the soldering pads.

8. The self-assembly method of an LED display device according to claim 1, wherein: In step S3, a second magnetic adsorption component is provided on the lower side of the collection plate; in step S4, before the magnetic end of the first magnetic adsorption component is brought close to the back of the driving board, the magnetic end of the second magnetic adsorption component is moved away from the front of the driving board; in step S5, the magnetic end of the first magnetic adsorption component is moved away from the back of the driving board, and the magnetic end of the second magnetic adsorption component is brought close to the back of the collection plate, so that the LED devices not captured by the soldering pad are released from the front of the driving board and adsorbed onto the collection plate by the second magnetic adsorption component.

9. The self-assembly method of an LED display device according to claim 8, wherein: The second magnetic adsorption member adopts a second electromagnet; in the step S4, the second electromagnet is powered off; in the step S5, the second electromagnet is also powered on, so that the LED devices not captured by the pad are released from the front of the driving board and adsorbed by the second electromagnet onto the collection board.

10. The self-assembly method of an LED display device according to claim 8, wherein: Before performing step S6, steps S4 to S5 are repeated to re-adsorb the LED devices dropped on the collecting plate onto the front of the driving plate, so that more LED devices are captured by the soldering pads.

11. The self-assembly method of an LED display device according to claim 1, wherein: The hot liquid is composed of molten rosin.

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