Mass transfer method of light-emitting diodes and transfer carrier plate thereof

Abstract

The invention provides a mass transfer method of light emitting diodes and a transfer carrier plate thereof, and belongs to the technical field of photoelectron manufacturing. The mass transfer method of the light-emitting diode comprises the steps that a plurality of pixel chips are transferred to a transfer carrier plate, the surface of the transfer carrier plate is provided with a stimulus response material layer, the pixel chips are located on the surface of the stimulus response material layer, and when the stimulus response material layer receives stimulus, the stimulus response material layer receives stimulus, and the stimulus response material layer is located on the surface of the stimulus response material layer. The viscosity of the stimulation response material layer is changed; stimulating the stimulus-responsive material layer to reduce the viscosity of the stimulus-responsive material layer; all the pixel chips are adhered to a seal adapter from the transfer carrier plate; and bonding the pixel chip to a circuit substrate by adopting the seal adapter. According to the invention, the problems that the pixel chip is easy to rebound on the temporary substrate and the seal adapter is not easy to adhere to the pixel chip can be improved.

Description

Technical Field

[0001] The present disclosure relates to the field of optoelectronic manufacturing technologies, and particularly to a method for massively transferring light-emitting diodes and a transfer carrier plate therefor. Background Art

[0002] In the emerging display field, Mini / Micro LEDs are continuously expanding the application boundaries of display screens. The light-emitting devices of MIP (MicroLED in package) include a plurality of pixel chips and a circuit substrate. The plurality of pixel chips are arranged at intervals on the circuit substrate and are bonded to the solder joints on the circuit substrate.

[0003] In related technologies, the process of massively transferring a plurality of pixel chips to a circuit substrate includes: First, the pixel chips prepared on a substrate are transferred to a temporary substrate by means of laser lift-off; Then, the pixel chips on the temporary substrate are adhered to a stamp adapter; Finally, the pixel chips are transferred to the circuit substrate through the stamp adapter, so that the pixel chips are bonded to the solder joints on the circuit substrate.

[0004] To prevent the pixel chips detached from the substrate from flying off due to bouncing when falling onto the temporary substrate, an adhesive is also formed on the temporary substrate to stick the falling pixel chips on the temporary substrate. If the viscosity of the adhesive is too small, it cannot prevent the pixel chips from bouncing; if the viscosity of the adhesive is too large, it will cause the problem that the stamp adapter is difficult to adhere the pixel chips from the temporary substrate. Summary of the Invention

[0005] Embodiments of the present disclosure provide a method for massively transferring light-emitting diodes and a transfer carrier plate therefor, which can improve the problems that pixel chips are prone to bounce on a temporary substrate and it is difficult for a stamp adapter to adhere pixel chips. The technical solutions are as follows:

[0006] Embodiments of the present disclosure provide a method for massively transferring light-emitting diodes. The massively transferring method includes: transferring a plurality of pixel chips to a transfer carrier plate, a stimulus-responsive material layer being provided on the surface of the transfer carrier plate, the pixel chips being located on the surface of the stimulus-responsive material layer, and when the stimulus-responsive material layer receives a stimulus, the viscosity of the stimulus-responsive material layer changes; stimulating the stimulus-responsive material layer to reduce the viscosity of the stimulus-responsive material layer; adhering each of the pixel chips from the transfer carrier plate to a stamp adapter; and bonding the pixel chips to a circuit substrate by using the stamp adapter.

[0007] In another implementation manner of the embodiments of the present disclosure, the stimulus-responsive material layer includes at least one of a thermosensitive material layer and a photosensitive material layer.

[0008] In another implementation manner of the embodiment of the present disclosure, the stimulus-responsive material layer includes a thermosensitive material layer; stimulating the stimulus-responsive material layer to reduce the adhesiveness of the stimulus-responsive material layer includes: heating the transfer carrier to 200°C to 300°C.

[0009] In another implementation manner of the embodiment of the present disclosure, the preparation materials of the thermosensitive material layer include at least one of Diels-Alder bond modified PI, PI-100 type, PI-PIF type, and Torlon.

[0010] In another implementation manner of the embodiment of the present disclosure, the stimulus-responsive material layer includes a photosensitive material layer; stimulating the stimulus-responsive material layer to reduce the adhesiveness of the stimulus-responsive material layer includes: irradiating the photosensitive material layer with ultraviolet light for 0.5 min to 5 min.

[0011] In another implementation manner of the embodiment of the present disclosure, the photosensitive material layer includes at least one of a polyimide material layer doped with an acrylate group and a polyimide material layer doped with a photosensitizer.

[0012] In another implementation manner of the embodiment of the present disclosure, preparing the transfer carrier includes: forming a PDMS layer on the transfer carrier; forming the stimulus-responsive material layer on the surface of the PDMS layer.

[0013] In another implementation manner of the embodiment of the present disclosure, the thickness of the PDMS layer is 20 μm to 50 μm, and the thickness of the stimulus-responsive material layer is 1 μm to 2 μm.

[0014] In another implementation manner of the embodiment of the present disclosure, adhering each of the pixel chips from the transfer carrier to the stamp adapter includes: forming a laser photosensitive adhesive layer on the surface of the stamp adapter; adhering each of the pixel chips to the stamp adapter by using the laser photosensitive adhesive layer; bonding the pixel chips to the circuit board by using the stamp adapter includes: laser irradiating the laser photosensitive adhesive layer to make the stamp adapter fall onto the circuit board.

[0015] The embodiment of the present disclosure provides a transfer carrier for a light-emitting diode, and the transfer carrier is used to implement the mass transfer method as described above.

[0016] The beneficial effects brought by the technical solution provided by the embodiment of the present disclosure at least include:

[0017] The massive transfer method provided by the embodiments of the present disclosure first transfers a plurality of pixel chips onto the stimulus-responsive material layer of a transfer carrier; then, the stimulus-responsive material layer is stimulated to reduce the viscosity of the stimulus-responsive material layer; in this way, when using a stamp adapter for transfer, since the viscosity of the stimulus-responsive material layer on the transfer carrier to the pixel chips is reduced, the stamp adapter can more easily adhere the pixel chips on the transfer carrier to the stamp adapter, improving the transfer efficiency of the pixel chips. Finally, the pixel chips are bonded to a circuit board using a stamp adapter, and the massive transfer operation of the pixel chips can be completed.

[0018] Compared with the related art, in the embodiments of the present disclosure, a stimulus-responsive material layer is first formed on the transfer carrier. Even if the viscosity of the stimulus-responsive material layer to the pixel chips is very high, when using a stamp adapter to transfer the pixel chips, the viscosity of the stimulus-responsive material layer can be reduced by stimulating the stimulus-responsive material layer, thereby facilitating the rapid transfer of each pixel chip to the stamp adapter and improving the transfer efficiency of the pixel chips. Moreover, the stimulus-responsive material layer has a certain viscosity. When the pixel chips are laser-stripped from the substrate, the pixel chips will adhere to the stimulus-responsive material layer and are not easily bounced off to cause the problem of flying chips, enabling the pixel chips to be accurately transferred to the required positions and improving the transfer efficiency of the pixel chips. Description of the Drawings

[0019] To more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 is a flowchart of a massive transfer method for a light-emitting diode provided by the embodiments of the present disclosure;

[0021] Figure 2 is a massive transfer state diagram of a light-emitting diode provided by the embodiments of the present disclosure;

[0022] Figure 3 is a massive transfer state diagram of a light-emitting diode provided by the embodiments of the present disclosure;

[0023] Figure 4 is a massive transfer state diagram of a light-emitting diode provided by the embodiments of the present disclosure;

[0024] Figure 5 is a massive transfer state diagram of a light-emitting diode provided by the embodiments of the present disclosure.

[0025] The descriptions of the marks in the figures are as follows:

[0026] 10, Pixel chip; 11, Red pixel chip; 12, Green pixel chip; 13, Blue pixel chip;

[0027] 20, Transfer carrier; 21, Stimulus-responsive material layer; 22, PDMS layer;

[0028] 30, Stamp adapter;

[0029] 40, Circuit board;

[0030] 50, Substrate;

[0031] 60, Heating plate. Specific embodiments

[0032] To make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will further describe the embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0033] Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meanings understood by those of ordinary skill in the art to which the present disclosure pertains. The terms "first", "second", "third", and similar terms used in the specification and claims of the present patent application do not denote any order, quantity, or importance, but are only used to distinguish different components. Similarly, terms such as "a" or "an" do not denote a quantity limitation, but mean that there is at least one. The terms "comprising" or "including" and similar terms mean that the elements or items appearing before "comprising" or "including" cover the elements or items listed after "comprising" or "including" and their equivalents, and do not exclude other elements or items. The terms "connected" or "coupled" and similar terms are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms "upper", "lower", "left", "right", "top", "bottom", etc. are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationships may also change accordingly.

[0034] Figure 1 is a flowchart of a method for massively transferring light-emitting diodes provided by an embodiment of the present disclosure. As Figure 1 shown, the method for massive transfer includes:

[0035] Step 101: Transfer a plurality of pixel chips 10 onto a transfer carrier 20.

[0036] Among them, the surface of the transfer carrier 20 is provided with a stimulus-responsive material layer 21, the pixel chip 10 is located on the surface of the stimulus-responsive material layer 21, and when the stimulus-responsive material layer 21 receives a stimulus, the viscosity of the stimulus-responsive material layer 21 changes.

[0037] Step 102: Stimulate the stimulus-responsive material layer 21 to reduce the adhesiveness of the stimulus-responsive material layer 21.

[0038] Step 103: Adhere each pixel chip 10 from the transfer carrier 20 to the stamp adapter 30.

[0039] Step 104: Bond the pixel chip 10 to the circuit board 40 using the stamp adapter 30.

[0040] For the massive transfer method provided by the embodiments of the present disclosure, first, a plurality of pixel chips 10 are transferred to the stimulus-responsive material layer 21 of the transfer carrier 20; then, the stimulus-responsive material layer 21 is stimulated to reduce the adhesiveness of the stimulus-responsive material layer 21. In this way, when transferring using the stamp adapter 30, since the adhesiveness of the stimulus-responsive material layer 21 on the transfer carrier 20 to the pixel chip 10 is reduced, the stamp adapter 30 can more easily adhere the pixel chip 10 on the transfer carrier 20 to the stamp adapter 30, improving the transfer efficiency of the pixel chip 10. Finally, bond the pixel chip 10 to the circuit board 40 using the stamp adapter 30 to complete the massive transfer operation of the pixel chip 10.

[0041] Compared with the related art, in the embodiments of the present disclosure, a stimulus-responsive material layer 21 is first formed on the transfer carrier 20. Even if the adhesiveness of the stimulus-responsive material layer 21 to the pixel chip 10 is very strong, when transferring the pixel chip 10 using the stamp adapter 30, the adhesiveness of the stimulus-responsive material layer 21 can be reduced by stimulating the stimulus-responsive material layer 21, thereby facilitating the rapid transfer of each pixel chip 10 to the stamp adapter 30 and improving the transfer efficiency of the pixel chip 10. Moreover, the stimulus-responsive material layer 21 has a certain adhesiveness. When laser peeling the pixel chip 10 from the substrate, the pixel chip 10 will adhere to the stimulus-responsive material layer 21 and is not easily bounced off to cause the problem of chip flying, enabling the pixel chip 10 to be accurately transferred to the required position and improving the transfer efficiency of the pixel chip 10.

[0042] Before step 101, preparing the transfer carrier 20 may be included.

[0043] Among them, the specific process of preparing the transfer carrier 20 may include the following steps:

[0044] The first step is to form a PDMS layer 22 on the transfer carrier 20.

[0045] As Figure 2 shown, a PDMS layer 22 is formed on the transfer carrier 20.

[0046] Among them, the PDMS layer 22 is a polydimethylsiloxane layer, and the polydimethylsiloxane layer is a high-molecular elastic polymer film prepared from polydimethylsiloxane as a raw material.

[0047] The Young's modulus of the PDMS layer 22 is low, it can withstand repeated stretching or bending without being easily broken, and it has elasticity. Thus, by disposing the PDMS layer 22 between the transfer carrier 20 and the stimulus-responsive material layer 21, when the pixel chip 10 falls onto the transfer carrier 20, the PDMS layer 22 can buffer the pixel chip 10, and can avoid the problem that the pixel chip 10 hard lands when falling onto the transfer carrier 20, resulting in the pixel chip 10 being chipped.

[0048] Specifically, it may include: fabricating a layer of PDMS layer 22 on a glass or sapphire substrate by means of spin coating, blade coating or printing. Then, the PDMS layer 22 is heated and cured. During the heating process, the heating temperature is controlled at 100 °C and lasts for 10 min to 30 min.

[0049] Exemplarily, the thickness of the PDMS layer 22 is 20 μm to 50 μm. For example, the thickness of the PDMS layer 22 is 30 μm.

[0050] By setting the thickness of the PDMS layer 22 within the above range, the PDMS layer 22 can exhibit higher resilience, and the ductility and cross-linked structure of its molecular chains can effectively disperse stress. Thus, when the pixel chip 10 falls onto the transfer carrier 20, the impact force when the pixel chip 10 falls can be absorbed by the PDMS layer 22, thereby preventing the pixel chip 10 from being chipped.

[0051] The second step is to form a stimulus-responsive material layer 21 on the surface of the PDMS layer 22.

[0052] As Figure 2 shown, a stimulus-responsive material layer 21 is formed on the surface of the PDMS layer 22.

[0053] Specifically, it may include: fabricating a layer of stimulus-responsive material layer 21 on the surface of the cured PDMS layer 22 by means of spin coating, blade coating or printing, and then heating and curing.

[0054] Exemplarily, the thickness of the stimulus-responsive material layer 21 is 1 μm to 2 μm. For example, the thickness of the stimulus-responsive material layer 21 is 1.5 μm.

[0055] By controlling the thickness of the stimulus-responsive material layer 21 within the above range, the transmission path of the stimulus signal inside the stimulus-responsive material can be significantly shortened, thereby improving the response speed.

[0056] Optionally, the stimulus-responsive material layer 21 includes at least one of a thermosensitive material layer and a photosensitive material layer.

[0057] Exemplarily, the stimulus-responsive material layer 21 is a thermosensitive material layer. Among them, after the thermosensitive material layer is heated, the viscosity of the thermosensitive material layer will decrease.

[0058] In one implementation, the thermosensitive material layer is a film layer obtained by modifying a polyimide material layer with dynamic covalent bonds.

[0059] In another implementation, the thermosensitive material layer is a film layer obtained by modifying a polyimide material layer by introducing some low-melting-point seasonings (such as paraffin) into the polyimide material layer.

[0060] Exemplarily, the thermosensitive material layer can be at least one of Diels-Alder bond modified PI, PI-100 type, PI-PIF type, and Torlon.

[0061] Exemplarily, the stimulus-responsive material layer 21 is a photosensitive material layer.

[0062] In one implementation, the photosensitive material layer includes a polyimide material layer doped with acrylate groups.

[0063] In another implementation, the photosensitive material layer includes a polyimide material layer doped with a photosensitizer.

[0064] Among them, the photosensitizer can be diazonaphthoquinone sulfonate (DNQ).

[0065] In the polyimide material layer doped with DNQ, after absorbing ultraviolet light, DNQ undergoes a photolysis reaction, the diazo group decomposes and releases nitrogen gas, reducing the adhesion of the polyimide material layer.

[0066] In the embodiments of the present disclosure, step 101 may include: transferring the pixel chip 10 prepared on the substrate to the transfer carrier 20.

[0067] Among them, the prepared pixel chip 10 may include a red pixel chip 11, a green pixel chip 12, and a blue pixel chip 13. Therefore, when transferring the pixel chip to the transfer carrier 20, three transfers are required to accurately place the pixel chips of different colors at the corresponding positions on the transfer carrier 20.

[0068] Exemplarily, as Figure 3 shown, laser irradiation is performed on the position of the red pixel chip 11 on the substrate 50, so that the red pixel chip 11 is peeled off from the substrate 50 and falls onto the stimulus-responsive material layer 21 of the transfer carrier 20.

[0069] In the embodiments of the present disclosure, each pixel chip includes an epitaxial layer, a passivation layer, and an electrode. The epitaxial layer is located on the surface of the substrate. The epitaxial layer includes a p-type layer, a light-emitting layer, and an n-type layer stacked in sequence. The n-type layer has a groove exposing the p-type layer. The passivation layer is located on the surface and in the groove of the n-type layer, and the passivation layer has a through hole exposing the n-type layer and the groove.

[0070] Among them, a first electrode and a second electrode are provided on the surface of the passivation layer, and the first electrode and the second electrode are respectively connected to the n-type layer and the p-type layer through two through holes.

[0071] For the red light pixel chip, the epitaxial layer is a red light epitaxial layer. For the green light pixel chip, the epitaxial layer is a green light epitaxial layer. For the blue light pixel chip, the epitaxial layer is a blue light epitaxial layer.

[0072] Among them, the red light epitaxial layer includes a first p-type layer, a first light-emitting layer, and a first n-type layer stacked in sequence.

[0073] In the red light epitaxial layer, the first p-type layer includes a p-type AlInP layer.

[0074] Among them, the first light-emitting layer includes alternately grown AlGaInP quantum well layers and AlGaInP quantum barrier layers, and among them, the Al content in the AlGaInP quantum well layers and the AlGaInP quantum barrier layers is different. The first light-emitting layer may include 3 to 8 periods of alternately stacked AlGaInP quantum well layers and AlGaInP quantum barrier layers.

[0075] Among them, the first n-type layer includes an n-type AlGaInP current spreading layer.

[0076] In the embodiments of the present disclosure, the green light epitaxial layer includes a second p-type layer, a second light-emitting layer, and a second n-type layer stacked in sequence.

[0077] In the green light epitaxial layer, the second p-type layer includes a p-type GaN layer.

[0078] Among them, the second light-emitting layer includes alternately grown InGaN quantum well layers and GaN quantum barrier layers. The second light-emitting layer may include 3 to 8 periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0079] Among them, the second n-type layer includes an n-type GaN layer.

[0080] In the embodiments of the present disclosure, the blue light epitaxial layer includes a third p-type layer, a third light-emitting layer, and a third n-type layer stacked in sequence.

[0081] In the blue light epitaxial layer, the third p-type layer includes a p-type GaN layer.

[0082] Among them, the third light-emitting layer may include alternately grown InGaN quantum well layers and GaN quantum barrier layers. The third light-emitting layer may include 3 to 8 periods of alternately stacked InGaN quantum well layers and GaN quantum barrier layers.

[0083] Among them, the third n-type layer includes an n-type GaN layer.

[0084] Optionally, the thickness of the pixel chip is from 2 μm to 10 μm.

[0085] Exemplarily, the thickness of the red light epitaxial layer is 5 μm, the thickness of the green light epitaxial layer is 8 μm, and the thickness of the blue light epitaxial layer is 6 μm.

[0086] In an embodiment of the present disclosure, when the stimulus-responsive material layer 21 includes a thermosensitive material layer, step 102 may include: heating the transfer carrier 20 to 200°C to 300°C.

[0087] As Figure 4 shown, it may specifically include: placing the transfer carrier 20 on the heating plate 60 and heating the transfer carrier 20 to 250°C through the heating plate 60.

[0088] Exemplarily, when the thermosensitive material layer is Diels-Alder bond modified PI, after heating the transfer carrier 20 to 250°C, the Diels-Alder bond undergoes reverse cleavage, resulting in the destruction of the crosslinked structure or cyclic unit originally formed by this reaction. This dynamic reversibility reduces the intermolecular connection and enhances the molecular mobility of Diels-Alder bond modified PI at high temperatures, thereby reducing the viscosity of Diels-Alder bond modified PI.

[0089] In an embodiment of the present disclosure, when the stimulus-responsive material layer 21 includes a photosensitive material layer, step 102 may include: irradiating the photosensitive material layer with ultraviolet light for 0.5 min to 5 min.

[0090] It may specifically include: placing the transfer carrier 20 on the UV irradiation device and irradiating the transfer carrier 20 with ultraviolet light through the UV irradiation device so that the ultraviolet light passes through the transfer carrier 20 and irradiates the photosensitive material layer.

[0091] Exemplarily, the photosensitive material layer is a polyimide material layer doped with DNQ. After irradiating the polyimide material layer doped with DNQ with ultraviolet light for 0.5 min, DNQ introduces hydrophilic carboxylic acid products into the PI system through a decomposition reaction triggered by ultraviolet light, destroys the intermolecular interaction and confers a plasticizing effect, ultimately resulting in a decrease in the viscosity of the polyimide material layer.

[0092] Step 103 may include: First, form a laser photosensitive adhesive layer on the surface of the stamp adapter 30. Then, use the laser photosensitive adhesive layer to adhere each pixel chip to the stamp adapter 30.

[0093] Step 104 may include: irradiating the laser photosensitive adhesive layer with a laser so that the stamp adapter 30 drops onto the circuit board 40.

[0094] Exemplarily, the laser photosensitive adhesive layer can be a KrF photoresist layer. After being irradiated by laser, the KrF photoresist layer will undergo an acid-catalyzed reaction, significantly reducing the adhesion force or decomposing.

[0095] Exemplarily, the preparation material of the laser photosensitive adhesive layer can also be a modified acrylate copolymer. This kind of preparation material is mainly composed of acrylate monomers (such as tert-butyl acrylate), and a strong light-absorbing group is introduced. Under laser, cross-linking or degradation is initiated, and the side chain breaks after exposure, resulting in the loss of viscosity.

[0096] As an example, the laser photosensitive adhesive layer can be a P(St-co-MMA) copolymer (styrene-methyl methacrylate copolymer). After laser irradiation, the adhesion force decreases by 90%.

[0097] In the embodiments of the present disclosure, by providing a laser photosensitive adhesive layer on the stamp adapter 30, the adhesion of the stamp adapter 30 can be improved, enabling the stamp adapter 30 to more easily adhere the pixel chip from the transfer carrier 20 to the stamp adapter 30; when it is necessary to transfer the pixel chip on the stamp adapter 30 to the circuit board 40, laser irradiation can be used on the laser photosensitive adhesive layer, so that the adhesion of the laser photosensitive adhesive layer to the pixel chip is reduced, enabling the pixel chip to fall onto the circuit board 40, thereby improving the transfer efficiency of the stamp adapter 30.

[0098] Exemplarily, the viscosity of the laser photosensitive adhesive layer can be 6 to 10 times greater than that of PDMS. In this case of the adhesion difference, the pick-up yield of the pixel chip can be guaranteed.

[0099] In the embodiments of the present disclosure, as Figure 5 shown, after transferring the pixel chip 10 to the circuit board 40, it may further include bonding each pixel chip 10 to the circuit board 40.

[0100] Specifically, it may include: after placing the pixel chip on the circuit board 40, bonding the pixel chip to the circuit board 40, heating the pads of the pixel chip and the solder joints on the circuit board 40 to form an Au / Sn bond, an Au / In bond or an ACF bond between the pixel chip and the circuit board 40.

[0101] Optionally, the circuit board 40 includes: a substrate board, a first conductive layer and a second conductive layer. The first conductive layer and the second conductive layer are respectively located on opposite sides of the substrate board, and through holes are provided on the substrate board. The through holes are filled with a conductive material, and the first conductive layer and the second conductive layer are electrically connected through the conductive material. Solder joints are also provided on the surface of the first conductive layer or the second conductive layer, and the solder joints are used to bind to the pads of the pixel chip so that the pixel chip is electrically connected to the conductive layer.

[0102] Specifically, it may include: as Figure 5As shown, each pixel chip and the solder joints on the circuit board 40 are bonded in one-to-one correspondence using a laser welding or hot press bonding process.

[0103] An embodiment of the present disclosure provides a transfer carrier 20 for a light-emitting diode, which is used to implement the mass transfer method as described above.

[0104] As Figure 2 shown, the transfer carrier 20 includes a transfer carrier 20, and a PDMS layer 22 and a stimulus-responsive material layer 21 stacked on the transfer carrier 20 in sequence.

[0105] Exemplarily, the transfer carrier can be a glass or sapphire substrate.

[0106] Exemplarily, the PDMS layer is a polydimethylsiloxane layer, and the thickness of the PDMS layer is 20 μm to 50 μm.

[0107] Optionally, the stimulus-responsive material layer includes at least one of a thermosensitive material layer and a photosensitive material layer.

[0108] Exemplarily, the stimulus-responsive material layer is a thermosensitive material layer. Among them, after the thermosensitive material layer is heated, the viscosity of the thermosensitive material layer will decrease.

[0109] In one implementation, the thermosensitive material layer is a film layer obtained by modifying a polyimide material layer through dynamic covalent bonds.

[0110] In another implementation, the thermosensitive material layer is a film layer obtained by modifying a polyimide material layer by introducing some low-melting-point seasonings (such as paraffin) into the polyimide material layer.

[0111] Exemplarily, the thermosensitive material layer can be at least one of Diels-Alder bond modified PI, PI-100 type, PI-PIF type, and Torlon.

[0112] Exemplarily, the stimulus-responsive material layer is a photosensitive material layer.

[0113] In one implementation, the photosensitive material layer includes a polyimide material layer doped with acrylate groups.

[0114] In another implementation, the photosensitive material layer includes a polyimide material layer doped with a photosensitizer.

[0115] Among them, the photosensitizer can be diazonaphthoquinone sulfonate (DNQ).

[0116] In the polyimide material layer doped with DNQ, after absorbing ultraviolet light, a photolysis reaction occurs to DNQ, the diazo group decomposes and releases nitrogen gas, resulting in a decrease in the adhesion of the polyimide material layer.

[0117] Exemplarily, the thickness of the stimulus-responsive material layer is from 1 μm to 2 μm. For example, the thickness of the stimulus-responsive material layer is 1.5 μm.

[0118] The above is not any form of limitation to the present disclosure. Although the present disclosure has been disclosed as above through embodiments, it is not intended to limit the present disclosure. Any person skilled in the art, without departing from the scope of the technical solution of the present disclosure, may make some changes or modifications to equivalent embodiments by using the technical content disclosed above. However, as long as it does not depart from the content of the technical solution of the present disclosure, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present disclosure still fall within the scope of the technical solution of the present disclosure.

Claims

1. A method for massive transfer of light-emitting diodes, characterized in that, The massive transfer method includes: Transferring a plurality of pixel chips (10) onto a transfer carrier (20), a stimulus-responsive material layer (21) being provided on the surface of the transfer carrier (2), the pixel chips (10) being located on the surface of the stimulus-responsive material layer (21), and when the stimulus-responsive material layer (21) receives a stimulus, the viscosity of the stimulus-responsive material layer (21) changes; Stimulating the stimulus-responsive material layer (21) to reduce the viscosity of the stimulus-responsive material layer (21); Adhering each of the pixel chips (10) from the transfer carrier (20) to a stamp adapter (30); Bonding the pixel chips (10) to a circuit board (40) using the stamp adapter (30).

2. The massive transfer method according to claim 1, wherein The stimulus-responsive material layer (21) includes at least one of a thermosensitive material layer and a photosensitive material layer.

3. The massive transfer method according to claim 2, wherein The stimulus-responsive material layer (21) includes a thermosensitive material layer; Stimulating the stimulus-responsive material layer (21) to reduce the viscosity of the stimulus-responsive material layer (21) includes: heating the transfer carrier (20) to 200°C to 300°C.

4. The massive transfer method according to claim 3, wherein The preparation materials of the thermosensitive material layer include at least one of Diels-Alder bond modified PI, PI-100 type, PI-PIF type, and Torlon.

5. The mass transfer method according to claim 2, wherein The stimulus-responsive material layer (21) includes a photosensitive material layer; Stimulating the stimulus-responsive material layer (21) to reduce the viscosity of the stimulus-responsive material layer (21) includes: irradiating the photosensitive material layer with ultraviolet light for 0.5 min to 5 min.

6. The massive transfer method according to claim 5, wherein The photosensitive material layer includes at least one of a polyimide material layer doped with an acrylate group and a polyimide material layer doped with a photosensitizer.

7. The massive transfer method according to any one of claims 1 to 6, characterized in that, Preparing the transfer carrier (20) includes: Forming a PDMS layer (22) on the transfer carrier (20); Forming the stimulus-responsive material layer (z1) on the surface of the PDMS layer (22).

8. The massive transfer method according to claim 7, wherein, The thickness of the PDMS layer (22) is 20 μm to 50 μm, and the thickness of the stimulus-responsive material layer (21) is 1 μm to 2 μm.

9. The massive transfer method according to any one of claims 1 to 6, characterized in that Adhering each of the pixel chips (10) from the transfer carrier (20) to the stamp adapter (30) includes: Forming a laser photosensitive adhesive layer on the surface of the stamp adapter (30); Adhering each of the pixel chips (10) to the stamp adapter (30) using the laser photosensitive adhesive layer; Bonding the pixel chips (10) to the circuit board (40) using the stamp adapter (30) includes: Irradiating the laser photosensitive adhesive layer with laser light to cause the stamp adapter (30) to drop onto the circuit board (40).

10. A transfer carrier for light-emitting diodes, characterized in that, The transfer carrier is used to implement the massive transfer method according to any one of claims 1 to 9.

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