Mass transfer device and mass transfer method

Abstract

The invention provides a mass transfer device and method, specifically, the mass transfer device comprises a transfer unit, a bearing unit, a vacuum assembly and a fixing assembly, the transfer unit is used for bearing a to-be-transferred substrate, the to-be-transferred substrate is provided with a light-emitting device, and the light-emitting device comprises a Micro-LED; the bearing unit is used for bearing a bearing substrate and can form a sealed cavity with the transfer unit; the vacuum assembly is used for realizing a vacuum state of a space between the to-be-transferred substrate and the bearing substrate; the fixing assembly is used for fixing the light-emitting device on the substrate to be transferred to the bearing substrate. The vacuum assembly can ensure the vacuum state of the space between the to-be-transferred substrate and the bearing substrate during the transfer operation of the huge transfer device, so that no impurity exists in the space, the fixing effect between the light-emitting device and the bearing substrate is good during the fixing operation of the fixing assembly, and the yield is improved.

Description

Technical Field

[0001] The present application belongs to the field of display technology, and specifically relates to a mass transfer device and a mass transfer method. Background Art

[0002] The comprehensive benefits of the Micro LED mass transfer process have always been one of the key issues restricting its mass production. In the prior art, if it is necessary to fix the substrate to be transferred in the transfer unit to the receiving substrate of the receiving unit, during the fixing process, after the transfer unit and the receiving unit are close to each other, there will be a problem of large bubbles formed in the contact surface between the light-emitting device and the receiving substrate. The bubbles will affect the uniformity of the bonding pressure; the bubbles generated during the bonding process will affect the pressing effect between the light-emitting device and the receiving substrate; when the receiving substrate is warped, there will be dead bubbles between the light-emitting device and the receiving substrate, and the dead bubbles cannot be discharged, resulting in poor fixing effect between the light-emitting device and the receiving substrate, affecting the product yield.

[0003] Therefore, there is an urgent need to improve issues such as welding yield in Micro LED mass transfer. Summary of the invention

[0004] The present application provides a mass transfer device and a mass transfer method, which can overcome the problem of welding yield in Micro LED mass transfer and improve the welding yield of Micro LED.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a mass transfer device, which includes a transfer unit, a receiving unit, a vacuum component and a fixing component, wherein the transfer unit is used to carry the substrate to be transferred, and there is a light-emitting device on the substrate to be transferred, and the light-emitting device includes a micro light-emitting diode Micro-LED; the receiving unit is used to carry the receiving substrate and can form a sealed cavity with the transfer unit; the vacuum component is used to achieve a vacuum state in the space between the substrate to be transferred and the receiving substrate; the fixing component is used to fix the light-emitting device on the substrate to be transferred to the receiving substrate.

[0006] The transfer unit includes a transfer platform and a sealing ring, wherein the transfer platform is used to carry the substrate to be transferred; the sealing ring is arranged on the transfer platform and surrounds the substrate to be transferred, and is used to form a sealed cavity with the receiving unit so that the vacuum component can extract the air in the sealed cavity.

[0007] Preferably, the transfer platform is also provided with a vacuum adsorption hole, and the vacuum component is connected to the position of the vacuum adsorption hole of the transfer platform.

[0008] Among them, the receiving unit includes a carrying platform and a lifting member, wherein the carrying platform is used to carry the receiving substrate; the lifting member is located on the carrying platform and surrounds the receiving substrate, the height of the lifting member relative to the carrying platform is adjustable, and after being raised, it abuts against the sealing ring to form a sealed cavity.

[0009] Among them, the receiving unit also includes a vacuum through hole, which is located between the lifting member and the carrying platform and is used to achieve a vacuum environment in the mass transfer device.

[0010] Preferably, the mass transfer device further comprises a vacuum pump connected to the vacuum through hole for extracting air from the sealed cavity to form a vacuum cavity.

[0011] Wherein, a protrusion is arranged on the side of the lifting member facing the sealing ring, and a groove is arranged on the side of the sealing ring facing the lifting member, and the protrusion can be inserted into the groove.

[0012] Preferably, the protrusion is a flexible body.

[0013] Preferably, in a direction parallel to the carrying platform, the length of the protrusion is smaller than the length of the groove, so that a clearance fit is formed between the side wall of the protrusion and the side wall of the groove after the sealed cavity is formed.

[0014] The receiving substrate is an array substrate, including a pixel circuit, and is electrically connected to the light-emitting device.

[0015] The fixing component includes a fiber laser or a solid-state laser, which is used to emit laser light to weld the light-emitting device to the array substrate so that the light-emitting device and the pixel circuit are connected.

[0016] Another technical solution adopted by the present application is to provide a mass transfer method, which is applied to the mass transfer device described in any one of the above embodiments, and the method includes:

[0017] The transfer unit clamps the substrate to be transferred, wherein the side of the substrate to be transferred with the light-emitting device integrated thereon faces the receiving unit; the receiving substrate is provided with a soldering pad, which is used to electrically connect with the light-emitting device; the transfer unit and the receiving unit are brought close to each other to form a sealed cavity; a vacuum is formed in the sealed cavity by using a vacuum component; and the light-emitting device is connected to the soldering pad of the receiving substrate by using a fixing component.

[0018] Among them, after the step of connecting the light-emitting device to the solder pad of the receiving substrate using a fixing component, the following steps are included: controlling the vacuum component to restore the atmospheric pressure in the sealed cavity; separating the receiving unit and the transfer unit, and the light-emitting device connected to the solder pad on the receiving substrate is transferred to the receiving substrate, and the light-emitting device not connected to the solder pad on the receiving substrate remains on the substrate to be transferred.

[0019] Among them, before the step in which the transfer unit clamps the substrate to be transferred, wherein the side of the substrate to be transferred with the light-emitting device integrated thereon faces the receiving unit, the method includes: applying a first adhesive material on a temporary substrate, and transferring the first light-emitting device, the second light-emitting device and the third light-emitting device among the light-emitting devices to the temporary substrate; applying a second adhesive material on the substrate to be transferred, so that the temporary substrate and the substrate to be transferred are relatively close, and the first light-emitting device, the second light-emitting device and the third light-emitting device on the first adhesive material are adhered to the second adhesive material, and the viscosity of the second adhesive material is greater than that of the first adhesive material; and separating the temporary substrate and the substrate to be transferred, so that the first light-emitting device, the second light-emitting device and the third light-emitting device are transferred to the substrate to be transferred.

[0020] Preferably, a side of the light emitting device facing away from the solder joint is adhered to the second adhesive material.

[0021] The beneficial effects of the present application are: through the above-mentioned design, the vacuum component can ensure the vacuum state of the space between the substrate to be transferred and the receiving substrate during the transfer operation of the mass transfer device, and there is no impurity in the space, and the vacuum design can reduce or even eliminate the bubbles on the contact surface between the light-emitting device and the receiving substrate after the light-emitting device on the substrate to be transferred is fixed to the receiving substrate, and when the fixing component performs the fixing operation, the fixing effect between the light-emitting device and the receiving substrate is good, and the yield is improved. Through the application of the fixing component in the present application, the time for curing the light-emitting device and the receiving substrate is shortened, and the fixing efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0023] Figure 1 It is a structural schematic diagram of an embodiment of a mass transfer device in the present application;

[0024] Figure 2 is a structural schematic diagram of another embodiment of the mass transfer device in the present application;

[0025] Figure 3 It is a structural schematic diagram of another embodiment of the mass transfer device in the present application;

[0026] Figure 4 It is a flow chart of an embodiment of a mass transfer method in the present application;

[0027] Figure 5 This application Figure 4 A schematic diagram of a flow chart of an embodiment after step S4;

[0028] Figure 6 It is a structural schematic diagram of another embodiment of the mass transfer device in the present application;

[0029] Figure 7 This application Figure 4 A schematic diagram of a flow chart of an embodiment before step S1;

[0030] Figure 8 It is a structural schematic diagram of an embodiment of a temporary substrate in the present application;

[0031] Fig. 9 is a top view of an embodiment of a temporary substrate in the present application;

[0032] Fig.10 It is a structural schematic diagram of an embodiment of the alignment of a temporary substrate and a substrate to be transferred in the present application;

[0033] Fig.11 It is a structural schematic diagram of an embodiment of a substrate to be transferred in the present application;

[0034] Explanation of the reference numerals: 11 substrate to be transferred; 12 light emitting device; 13 transfer platform; 15 groove; 16 vacuum adsorption hole; 21 carrying platform; 22 lifting member; 23 protrusion; 24 vacuum through hole; 25 receiving substrate; 26 solder; 4 fixing component; 5 temporary substrate; 6 first adhesive material; 121 first light emitting device; 122 second light emitting device; 123 third light emitting device; 7 second adhesive material; 17 solder joint; L1 protrusion length; L2 groove length; X first direction. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0036] See also Figure 1 and Figure 2 The present application provides a mass transfer device, which includes a transfer unit, a receiving unit, a vacuum component and a fixing component, wherein the transfer unit is used to carry a substrate 11 to be transferred, and a light-emitting device 12 is provided on the substrate 11 to be transferred, and the light-emitting device 12 includes a micro light-emitting diode Micro-LED; the receiving unit is used to carry a receiving substrate 25 and can form a sealed cavity with the transfer unit; the vacuum component (not shown) is used to achieve a vacuum state in the space between the substrate 11 to be transferred and the receiving substrate 25; the fixing component is used to fix the light-emitting device 12 on the substrate 11 to be transferred to the receiving substrate 25.

[0037] The mass transfer device in the present application can fix the substrate to be transferred 11 in the transfer unit to the receiving substrate 25 of the receiving unit. The substrate to be transferred 11 is fixed by the transfer unit. At the same time, the transfer unit can replace the fixed substrate to be transferred 11 to fix different substrates to be transferred 11. There is a light-emitting device 12 on the substrate to be transferred 11, wherein the light-emitting device 12 includes a micro light-emitting diode Micro-LED. The Micro-LED can be densely arranged in an array on the substrate to be transferred 11 for transfer. The vacuum component can realize a vacuum environment during the operation of the mass transfer device, so that during the transfer operation, there is a vacuum environment between the substrate to be transferred 11 and the receiving substrate 25. The fixing component fixes the light-emitting device 12 on the substrate to be transferred 11 to the receiving substrate 25 by different fixing methods.

[0038] By using the vacuum component, a vacuum environment is achieved during the transfer operation, and there are no impurities in the working chamber, which can reduce the bubbles in the copolymer compound formed after the light-emitting device 12 and the receiving substrate 25 are fixed, and form a higher-density alloy compound. It can also prevent the receiving substrate 25 and the light-emitting device 12 from being too tightly bonded, resulting in a dead bubble phenomenon that causes a poor pressing effect, thereby further improving the product yield.

[0039] Through the above design, the vacuum component can ensure the vacuum state of the sealed cavity between the substrate to be transferred 11 and the receiving substrate 25 during the transfer operation of the mass transfer device, and there is no impurity in the sealed cavity; at the same time, the vacuum design can reduce or even eliminate the bubbles on the contact surface between the light-emitting device 12 and the receiving substrate 25 after the light-emitting device 12 on the substrate to be transferred 11 is fixed to the receiving substrate 25, so that when the fixing component performs the fixing operation, the fixing effect between the light-emitting device 12 and the receiving substrate 25 is good, and the yield is improved. Through the application of the fixing component in this application, the time for curing the light-emitting device 12 and the receiving substrate 25 is shortened, and the fixing efficiency can be improved.

[0040] Please continue reading Figure 1 and Figure 2 The transfer unit includes a transfer platform 13 and a sealing ring (not shown), wherein the transfer platform 13 is used to carry the substrate 11 to be transferred; the sealing ring is arranged on the transfer platform 13 and surrounds the substrate 11 to be transferred, and is used to form a sealed cavity with the receiving unit, so that the vacuum component can extract the air in the sealed cavity. Specifically, the substrate 11 to be transferred is fixed by the transfer platform 13, and the sealing ring is located around the substrate 11 to be transferred. When the transfer unit and the receiving unit are close to each other, the sealing ring can be surrounded by the receiving unit to form a sealed cavity. At this time, the vacuum component can extract the air in the sealed cavity to form a vacuum cavity, which is convenient for the fixing operation between the light-emitting device 12 and the receiving substrate 25.

[0041] Preferably, the transfer platform 13 is also provided with a vacuum adsorption hole 16, and the vacuum component is connected to the position of the vacuum adsorption hole 16 of the transfer platform 13. The vacuum adsorption hole 16 connects the vacuum component and the substrate to be transferred 11, and the vacuum adsorption hole 16 is located on the transfer platform 13, so that the transfer unit can realize vacuum adsorption of the substrate to be transferred 11. After the transfer operation is completed, the transfer unit and the substrate to be transferred 11 can be separated by breaking the vacuum. Of course, in the present application, the transfer unit can also fix the substrate to be transferred 11 by other means, such as abutment, by bringing the two side structures of the transfer platform 13 close to each other, so as to fix the substrate to be transferred 11 on the transfer platform 13.

[0042] Please continue reading Figure 1 and Figure 2 , the receiving unit includes a carrying platform 21 and a lifting member 22, wherein the carrying platform 21 is used to carry a receiving substrate 25; the lifting member 22 is located on the carrying platform 21 and surrounds the receiving substrate 25, the height of the lifting member 22 relative to the carrying platform 21 is adjustable, and after being raised, it abuts against the sealing ring to form a sealed cavity. The receiving substrate 25 can be placed on the carrying platform 21 of the receiving unit and moves with the carrying platform 21. The carrying platform 21 is provided with a lifting member 22, which surrounds the receiving substrate 25, and the height of the lifting member 22 relative to the carrying platform 21 can be changed, so that the height of the carrying platform 21 is adjustable, and when the lifting member 22 is raised, it can abut against the sealing ring to form a sealed cavity between the receiving unit and the transfer unit.

[0043] In one embodiment, the lifting member 22 includes a cylinder that can be pulled up freely, and the cylinder can provide uniform pressure in the vacuum chamber. At the same time, when the set pressure is slightly greater than the gravity of the cylinder mechanism itself, it will not affect the parallelism adjustment between the receiving substrate 25 and the substrate to be transferred 11 under the vacuum state. In the vacuum chamber, the atmospheric pressure presses the substrate to be transferred 11, causing the substrate to be transferred 11 to descend. At the same time, in the receiving unit, the pressure on the cylinder basically offsets its own weight and part of the friction force, so the air pressure can be evenly distributed, so that the overall air pressure in the vacuum chamber is uniform.

[0044] Please continue reading Figure 1 and Figure 2 The receiving unit also includes a vacuum through hole 24, which is located between the lifting member 22 and the carrying platform 21, and is used to achieve a vacuum environment in the mass transfer device. The vacuum component also includes a vacuum pump, which is connected to the vacuum through hole 24 and is used to extract air from the sealed cavity to form a vacuum cavity. The vacuum through hole 24 is connected to the sealed cavity. When the vacuum pump evacuates the cavity through the vacuum through hole 24, it is helpful to convert the sealed cavity in the mass transfer device into a vacuum cavity. The vacuum through hole 24 is located between the lifting member 22 and the carrying platform 21, so that the position of the vacuum through hole 24 will not affect the fixation between the light-emitting device 12 and the receiving substrate 25.

[0045] In one embodiment, a protrusion 23 is provided on the side of the lifting member 22 facing the sealing ring, and a groove 15 is provided on the side of the sealing ring facing the lifting member 22, and the protrusion 23 can be inserted into the groove 15; when the protrusion 23 in the lifting member 22 is inserted into the groove 15 in the sealing ring, a sealed cavity is formed between the receiving unit and the transfer unit.

[0046] In one embodiment, the protrusion 23 is a flexible body. When the protrusion 23 is a flexible body, when it is aligned between the lifting member 22 and the sealing ring, the flexible body can undergo a certain deformation, which can reduce the wear of the protrusion 23.

[0047] Please continue reading Figure 1 , in the direction parallel to the carrying platform 21, that is, in the first direction X, the length L1 of the protrusion 23 is less than the length L2 of the groove 15, so that the clearance between the side wall of the protrusion 23 and the side wall of the groove 15 is matched after the sealed cavity is formed. The clearance between the side wall of the protrusion 23 and the side wall of the groove 15 can reduce the wear of the protrusion 23 during the alignment process of the transfer unit and the receiving unit, and ensure the sealing effect of the sealed cavity. At the same time, the clearance makes it possible to fine-tune the position of the receiving unit after alignment. The adjustment space is the difference between the length L1 of the protrusion 23 and the length L2 of the groove 15. By fine-tuning the position of the receiving unit after alignment, the fixed position between the light-emitting device 12 and the receiving substrate 25 can be adjusted to improve the alignment accuracy.

[0048] In one embodiment, the receiving substrate 25 is an array substrate, including a pixel circuit, and is electrically connected to the light emitting device 12. When the receiving substrate 25 is an array substrate, the mass transfer device can directly fix the light emitting device 12 on the substrate to be transferred 11 to the array substrate, and realize the electrical connection between the pixel circuit in the array substrate and the light emitting device 12, thereby improving the preparation efficiency of Micro LED products.

[0049] See also Figure 3 The fixing component 4 includes a fiber laser or a solid-state laser, which is used to emit laser light to weld the light-emitting device 12 to the array substrate, so that the light-emitting device 12 is connected to the pixel circuit. When the fixing component 4 is a fiber laser or a solid-state laser, the welding between the light-emitting device 12 and the receiving substrate 25 can be completed within a dozen seconds, and the laser welding temperature is high, the fixing effect is relatively good, and the copolymer compound in the solder joint 17 after welding has few pores and a low void rate. In addition, the fiber laser or the solid-state laser can form a uniform light spot through optical shaping, and the light spot irradiates the receiving substrate 25 from the front after passing through the light-emitting device 12, thereby realizing the whole-surface welding of the receiving substrate 25.

[0050] The present application also provides a mass transfer method, which is applied to the mass transfer device described in any one of the above embodiments. Specifically, please refer to Figure 4 , mass transfer methods include:

[0051] S1: The transfer unit clamps the substrate 11 to be transferred, wherein the side of the substrate 11 to be transferred with the light emitting device 12 integrated thereon faces the receiving unit; the receiving substrate 25 has a soldering pad for electrically connecting with the light emitting device 12 .

[0052] Please continue reading Figure 1 , the transfer unit fixes the substrate to be transferred 11, and the side of the substrate to be transferred 11 with the light emitting device 12 integrated thereon faces the receiving unit. The receiving substrate 25 has a pad fixed to the light emitting device 12, and the electrical connection between the receiving substrate 25 and the light emitting device 12 is achieved through the pad. In one embodiment, solder 26 can be placed at the corresponding position of the pad, and the pad is connected to the light emitting device 12 through the solder 26. The position of the solder 26 corresponds to the position of the pad in the array substrate, and the solder 26 will melt under high temperature or laser irradiation, so that the light emitting device 12 and the receiving substrate 25 are electrically connected.

[0053] S2: The transfer unit and the receiving unit are brought close to each other to form a sealed cavity.

[0054] Please continue reading Figure 2 After the transfer unit and the receiving unit are close to each other, the protrusion 23 in the lifting member 22 is inserted into the groove 15 in the sealing ring, so that a sealed cavity is formed between the receiving unit and the transfer unit. Specifically, the height of the lifting member 22 relative to the carrying platform 21 is adjustable, and after being raised, it abuts against the sealing ring to form a sealed cavity.

[0055] S3: Using a vacuum assembly to form a vacuum in the sealed cavity.

[0056] The vacuum through hole 24 is located between the lifting member 22 and the carrying platform 21, and is used to realize the vacuum environment in the mass transfer device. The vacuum component also includes a vacuum pump, which is connected to the vacuum through hole 24 and is used to extract the air in the sealed cavity to form a vacuum cavity. The vacuum through hole 24 is connected to the sealed cavity, and when the vacuum pump evacuates through the vacuum through hole 24, the sealed cavity in the mass transfer device is converted into a vacuum cavity.

[0057] S4: Use the fixing assembly 4 to connect the light emitting device 12 to the pad of the receiving substrate 25 .

[0058] Please continue reading Figure 3In one embodiment, the fixing component 4 includes a fiber laser or a solid-state laser, which is used to emit laser light to weld the light-emitting device 12 to the receiving substrate 25, thereby realizing electrical connection between the light-emitting device 12 and the pixel circuit. When the fixing component 4 is a fiber laser or a solid-state laser, the welding between the light-emitting device 12 and the receiving substrate 25 can be completed within a dozen seconds, with high operating efficiency and good welding effect.

[0059] See also Figure 5 , after step S4, comprising:

[0060] S41: Control the vacuum assembly to restore the sealed cavity to atmospheric pressure;

[0061] After the light-emitting device 12 is connected to the pad of the receiving substrate 25 by using the fixing component 4, the vacuum component can be controlled to stop delivering negative pressure into the sealed cavity. By delivering atmospheric pressure into the sealed cavity, the atmospheric pressure in the sealed cavity can be restored to break the vacuum.

[0062] S42: Separating the receiving unit and the transfer unit, the light emitting device 12 connected to the pad on the receiving substrate 25 is transferred to the receiving substrate 25, and the light emitting device 12 not connected to the pad on the receiving substrate 25 remains on the substrate 11 to be transferred.

[0063] See also Figure 6 After the above operation steps, the bonding force between the light-emitting unit connected to the pad and the receiving substrate 25 is greater than the bonding force between the light-emitting unit connected to the pad and the receiving substrate 25 and the substrate 11 to be transferred. Therefore, after the receiving unit and the transfer unit are separated, the light-emitting device 12 connected to the pad on the receiving substrate 25 is transferred to the receiving substrate 25, and the light-emitting device 12 not connected to the pad on the receiving substrate 25 remains on the substrate 11 to be transferred. The light-emitting device 12 remaining on the substrate 11 to be transferred can be transferred to the corresponding receiving substrate 25 in the next mass transfer operation. Therefore, the selective transfer of the light-emitting device 12 can be achieved in the present application.

[0064] See also Figure 7 and Figure 8 , before step S1, comprising:

[0065] S11 : coating a first adhesive material 6 on the temporary substrate 5 , and transferring the first light emitting device 121 , the second light emitting device 122 , and the third light emitting device 123 in the light emitting device 12 to the temporary substrate 5 .

[0066] See also Fig. 9The first adhesive material 6 can be made of polydimethylsiloxane (PDMS), which is a high molecular polymer. The first adhesive material 6 can be evenly spin-coated onto the temporary substrate 5, and then the light-emitting devices 12 are transferred from the growth substrates corresponding to different light-emitting devices 12 to the temporary substrate 5 to form a Fig. 9 The light emitting devices 12 are densely arranged in the structure shown, wherein the first light emitting device 121 is a red light emitting device, the second light emitting device 122 is a green light emitting device, and the third light emitting device 123 is a blue light emitting device.

[0067] S12: Apply the second adhesive material 7 on the substrate 11 to be transferred, make the temporary substrate 5 and the substrate 11 to be transferred relatively close, and stick the first light-emitting device 121, the second light-emitting device 122 and the third light-emitting device 123 on the first adhesive material 6 to the second adhesive material 7. The viscosity of the second adhesive material 7 is greater than that of the first adhesive material 6.

[0068] See also Fig.10 The second adhesive material 7 can also be made of polydimethylsiloxane (PDMS), and the second adhesive material 7 is evenly spin-coated onto the substrate 11 to be transferred, and the viscosity of the second adhesive material 7 is greater than the viscosity of the first adhesive material 6, so that after the temporary substrate 5 and the substrate 11 to be transferred are relatively close, the first light-emitting device 121, the second light-emitting device 122 and the third light-emitting device 123 on the first adhesive material 6 can be adhered to the second adhesive material 7.

[0069] S13 : separating the temporary substrate 5 and the substrate to be transferred 11 , so that the first light emitting device 121 , the second light emitting device 122 and the third light emitting device 123 are all transferred onto the substrate to be transferred 11 .

[0070] See also Fig.11 Since the viscosity of the second adhesive material 7 is greater than that of the first adhesive material 6, after the temporary substrate 5 and the substrate to be transferred 11 are separated, the adhesion between the light emitting device 12 and the second adhesive material 7 is greater than the adhesion between the light emitting device 12 and the first adhesive material 6, and the light emitting device 12 is separated from the first adhesive material 6 on the temporary substrate 5, and then adheres to the second adhesive material 7 on the substrate to be transferred 11. At the same time, the first light emitting device 121, the second light emitting device 122 and the third light emitting device 123 are all transferred to the substrate to be transferred 11.

[0071] Preferably, the side of the light emitting device 12 facing away from the solder joint 17 is adhered to the second adhesive material 7, so that the solder joint 17 in the light emitting device 12 and the solder pad on the receiving substrate 25 are connected during the mass transfer operation.

[0072] In addition, by increasing the viscosity of the second adhesive material 7, the adhesion of the second adhesive material 7 to the light-emitting device 12 is increased. After welding is completed, the second adhesive material 7 can take away the light-emitting device 12 with weaker bonding to the solder joint 17 to ensure the welding effect. Specifically, the fixing component 4 emits a laser beam to weld the light-emitting device 12 to the receiving substrate 25. Due to various factors, there may be a problem of weak bonding between a very small number of light-emitting devices 12 and the receiving substrate 25, which will cause the light-emitting device 12 to fail during use and have a short life. By adjusting the viscosity of the second adhesive material 7, the adhesion of the second adhesive material 7 to the light-emitting device 12 changes. Specifically, when the viscosity of the second adhesive material 7 increases, the adhesion of the second adhesive material 7 to the light-emitting device 12 increases. When the adhesion of the second adhesive material 7 to the light emitting device 12 is greater than the bonding force between the light emitting device 12 and the receiving substrate 25, the light emitting device 12 will still adhere to the second adhesive material 7 after the substrate 11 to be transferred and the receiving substrate 25 are separated, so that the light emitting device 12 with weak bonding force to the receiving substrate 25 cannot remain on the receiving substrate 25. Therefore, by changing the viscosity of the second adhesive material 7 and increasing the adhesion of the second adhesive material 7 to the light emitting device 12, the light emitting device 12 with weak bonding force to the receiving substrate 25 after welding can be screened out, so that the light emitting device 12 still adheres to the second adhesive material 7 and is not transferred to the receiving substrate 25, and the light emitting device 12 with strong bonding force to the receiving substrate 25 after welding will not be taken away by the second adhesive material 7 and is still fixed on the receiving substrate 25, thereby ensuring the bonding force between the receiving substrate 25 and the light emitting device 12 after the second adhesive material 7 is removed, and avoiding the problem of easy failure of the light emitting device 12 when the bonding force between the light emitting device 12 and the receiving substrate 25 is not strong.

[0073] The above description is only an embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A mass transfer device, characterized in that: The device comprises: A transfer unit, the transfer unit is used to carry a substrate to be transferred, the substrate to be transferred has a light-emitting device, and the light-emitting device includes a micro light-emitting diode Micro-LED; A receiving unit, the receiving unit is used to carry the receiving substrate and can form a sealed cavity with the transfer unit; A vacuum component, used to achieve a vacuum state in the space between the substrate to be transferred and the receiving substrate; A fixing assembly is used to fix the light emitting device on the substrate to be transferred to the receiving substrate.

2. The mass transfer device according to claim 1, characterized in that: The transfer unit comprises: A transfer platform, used for carrying the substrate to be transferred; A sealing ring, disposed on the transfer platform and surrounding the substrate to be transferred, and used to enclose the receiving unit to form the sealed cavity, so that the vacuum component can extract the air in the sealed cavity; Preferably, the transfer platform is further provided with: a vacuum adsorption hole, and the vacuum component is connected to the position of the vacuum adsorption hole of the transfer platform.

3. The mass transfer device according to claim 2, characterized in that: The receiving unit comprises: A carrying platform, used for carrying the receiving substrate; A lifting member is located on the carrying platform and surrounds the receiving substrate. The height of the lifting member relative to the carrying platform is adjustable, and after being lifted, it abuts against the sealing ring to form the sealing cavity.

4. The mass transfer device according to claim 3, characterized in that: The receiving unit also includes: A vacuum through hole, located between the lifting member and the carrying platform, for realizing a vacuum environment in the mass transfer device; Preferably, the vacuum assembly further comprises: A vacuum pump is connected to the vacuum through hole and is used to extract air from the sealed cavity to form a vacuum cavity.

5. The mass transfer device according to claim 3, characterized in that: A protrusion is provided on a side of the lifting member facing the sealing ring, and a groove is provided on a side of the sealing ring facing the lifting member, and the protrusion can be inserted into the groove; Preferably, the protrusion is a flexible body; Preferably, in a direction parallel to the carrying platform, the length of the protrusion is smaller than the length of the groove, so that after the sealing cavity is formed, a clearance fit is achieved between the side wall of the protrusion and the side wall of the groove.

6. The mass transfer device according to claim 1, characterized in that: The receiving substrate is an array substrate, including a pixel circuit, and is electrically connected to the light emitting device.

7. The mass transfer device according to claim 6, characterized in that: The fixing component includes a fiber laser or a solid-state laser, which is used to emit laser light to weld the light-emitting device to the array substrate, so that the light-emitting device is connected to the pixel circuit.

8. A method for mass transfer, characterized in that: The method is applied to the mass transfer device according to any one of claims 1 to 7, and the method comprises: The transfer unit clamps the substrate to be transferred, wherein a side of the substrate to be transferred on which the light-emitting device is integrated faces the receiving unit; a soldering pad is provided on the receiving substrate, and the soldering pad; Bringing the transfer unit and the receiving unit close to each other to form the sealed cavity; Using the vacuum assembly to form a vacuum in the sealed cavity; The light emitting device is connected to the pad of the receiving substrate by using a fixing component.

9. The method for mass transfer according to claim 8, characterized in that: After the light emitting device is connected to the pad of the receiving substrate by using a fixing component, the method includes: Controlling the vacuum assembly to restore the sealed cavity to atmospheric pressure; The receiving unit and the transfer unit are separated, the light-emitting device connected to the pad on the receiving substrate is transferred to the receiving substrate, and the light-emitting device not connected to the pad on the receiving substrate remains on the substrate to be transferred.

10. The method for mass transfer according to claim 9, characterized in that: The transfer unit clamps the substrate to be transferred, wherein before the step of facing the receiving unit with a side of the substrate to be transferred having the light emitting device integrated thereon, the step includes: Applying a first adhesive material on a temporary substrate, and transferring the first light-emitting device, the second light-emitting device, and the third light-emitting device among the light-emitting devices to the temporary substrate; Applying a second adhesive material on the substrate to be transferred, bringing the temporary substrate and the substrate to be transferred relatively close to each other, and adhering the first light-emitting device, the second light-emitting device and the third light-emitting device on the first adhesive material to the second adhesive material, wherein the viscosity of the second adhesive material is greater than that of the first adhesive material; Separating the temporary substrate and the substrate to be transferred, so that the first light-emitting device, the second light-emitting device and the third light-emitting device are all transferred to the substrate to be transferred; Preferably, a side of the light emitting device facing away from the solder joint is adhered to the second adhesive material.

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