Transfer carrier plate and method of making a transfer carrier plate

Abstract

Embodiments of the present application relate to the technical field of chip transfer, and particularly relate to a transfer carrier plate and a manufacturing method thereof. The transfer carrier plate comprises: a substrate, one side of the substrate having a chip adsorption area; a first encapsulation layer located around the chip adsorption area; a low-boiling expansion layer covering the chip adsorption area; and a thermoplastic layer located above the low-boiling expansion layer and the first encapsulation layer. The technical solution of the present application improves the risk that the chip is trapped in the glue layer and cannot be pulled out, and the risk that the glue is left on the chip, while the requirement for the equipment process is relatively low, the production cost can be reduced, and the problem that the heat release causes damage to the chip is solved.

Description

Technical Field

[0001] This application relates to the field of chip transfer technology, and more particularly to a transfer substrate and a method for manufacturing the transfer substrate. Background Technology

[0002] The manufacturing process of Mini-LED chips and Micro-LED chips generally includes chip fabrication, chip transfer, and bonding of the chip to the driving substrate. Among these, chip transfer is a crucial step in the process.

[0003] Currently, chip transfer solutions mainly include flexible stamp micro-transfer technology and laser selective release technology. Flexible stamp micro-transfer technology utilizes the adhesive force between a flexible stamp and the chip to pick up the chip from the source substrate. By reducing or eliminating the adhesive force, the chip detaches onto the driving substrate, enabling the transfer of large numbers of chips. Laser selective release technology directly uses laser irradiation from the source substrate to cause the chip to fall directly onto the driving substrate, or it first uses a photosensitive adhesive coated with a laser to pick up the chip, and then uses laser irradiation to reduce or eliminate the adhesive force between the photosensitive adhesive and the chip, causing the chip to detach onto the driving substrate.

[0004] Flexible micro-transfer technology places high demands on the selection and preparation of the adhesive. For example, the adhesive must be of uniform thickness, have a smooth surface, and not be too thick; otherwise, the chip will become stuck in the adhesive and cannot be removed. Furthermore, adhesive residue is easily left on the chip during the transfer process and is difficult to remove. Laser transfer technology requires laser equipment and photosensitive adhesives that react with specific laser wavelengths, resulting in higher costs. Additionally, the heat released during laser emission may damage the chip. Summary of the Invention

[0005] Based on this, it is necessary to address the above-mentioned technical problems. This application provides a transfer substrate and a method for manufacturing the transfer substrate, which improves the risk of the chip being trapped in the adhesive layer and unable to be pulled out, as well as the risk of adhesive residue on the chip. At the same time, it has lower requirements for equipment and process, can reduce production costs, and solves the problem of heat release causing damage to the chip.

[0006] In a first aspect, embodiments of this application also provide a transfer carrier plate, comprising:

[0007] A substrate, one side of which includes a chip adsorption region;

[0008] The first encapsulation layer is located around the chip adsorption area;

[0009] a low-boiling point expansion layer covering the chip adsorption area of the substrate;

[0010] a thermoplastic layer above the low-boiling point expansion layer and the first encapsulation layer.

[0011] In some embodiments, the transfer carrier further comprises:

[0012] a second encapsulation layer disposed between the thermoplastic layer and the low-boiling point expansion layer and above the low-boiling point expansion layer and the first encapsulation layer.

[0013] In some embodiments, the low-boiling point expansion layer comprises a porous adsorption layer and a low-boiling point liquid organic material injected into the porous adsorption layer.

[0014] In a second aspect, embodiments of the present application provide a method for manufacturing a transfer carrier, comprising:

[0015] forming a first encapsulation layer around the chip adsorption area on one side of the substrate;

[0016] forming a low-boiling point expansion layer in the chip adsorption area;

[0017] covering a thermoplastic layer above the low-boiling point expansion layer and the first encapsulation layer.

[0018] In some embodiments, before covering a thermoplastic layer above the low-boiling point expansion layer and the first encapsulation layer, the method further comprises:

[0019] covering a second encapsulation layer above the low-boiling point expansion layer and the first encapsulation layer. In some embodiments, forming a low-boiling point expansion layer in the chip adsorption area comprises:

[0020] forming a porous adsorption layer in the chip adsorption area;

[0021] injecting a low-boiling point liquid organic material into the porous adsorption layer to form a low-boiling point expansion layer.

[0022] In some embodiments, after covering a second encapsulation layer above the low-boiling point expansion layer and the first encapsulation layer, the method further comprises:

[0023] sealing the low-boiling point expansion layer with the second encapsulation layer.

[0024] In some embodiments, the thermoplastic layer corresponding to the chip adsorption area in the transfer carrier adheres the chip at room temperature.

[0025] In some embodiments, the transfer carrier with the adhered chip is heated to a preset temperature, so that the chip falls off on the driving substrate.

[0026] In some embodiments, the method for manufacturing a transfer carrier further comprises:

[0027] The ambient temperature is maintained at less than or equal to 120°.

[0028] In a third aspect, the embodiments of the present application further provide a transfer device, comprising:

[0029] The transfer carrier as claimed in the first aspect;

[0030] A driving substrate, a driving electrode on the driving substrate is used to fix the chip transferred by the transfer carrier.

[0031] In a fourth aspect, the embodiments of the present application further provide a chip transfer method, applying the transfer device as claimed in the third aspect, comprising:

[0032] Adhering the chip by using the transfer carrier;

[0033] Heating the transfer carrier adhering the chip to a preset temperature, so that the chip is detached on the driving substrate.

[0034] The transfer carrier provided by the embodiments of the present application comprises a substrate, one side of the substrate has a chip adsorption area; a first packaging layer is located around the chip adsorption area; a low-boiling expansion layer covers the chip adsorption area; and a thermoplastic layer is located above the low-boiling expansion layer and the first packaging layer. Thus, after the transfer carrier adsorbs the chip, the transfer carrier is heated to a temperature of, for example, 110° C, the chip adsorbed by the transfer carrier is subjected to a pushing force generated by the expansion of the expansion layer, and the thermoplastic glue in the thermoplastic layer has a large softening flowability after being heated, so that the adhesion between the chip and the thermoplastic layer is greatly reduced, and the chip can be detached on the driving substrate, thereby realizing the transfer of the chip by the transfer carrier. Compared with the elastic stamp microtransfer printing technology, the pushing force generated by the expansion of the low-boiling expansion layer in the technical solution of the present application improves the risk that the chip is trapped in the glue layer and cannot be pulled out, and the glue is left on the chip. Compared with the laser transfer technology, the technical solution of the present application only needs to be heated to complete the transfer, and the requirement for the equipment process is low, so that the production cost can be reduced. Since the heating temperature is within the bearing range of the chip, the problem that the heat release generated by the laser transfer technology causes damage to the chip is solved. BRIEF DESCRIPTION OF DRAWINGS

[0035] The drawings incorporated into the specification and forming a part thereof, illustrate embodiments consistent with the present application and, together with the specification, serve to explain the principles of the present application.

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings required to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0037] Figure 1 A cross-sectional structure schematic diagram of a transfer carrier provided by an embodiment of the present application is shown in FIG. 1.

[0038] Figure 2 A cross-sectional structure schematic diagram of another transfer carrier provided by an embodiment of the present application is shown in FIG. 2.

[0039] Figure 3 A flowchart of a manufacturing method of a transfer carrier provided by an embodiment of the present application is shown in FIG. 3.

[0040] Figure 4 A process flowchart of a manufacturing method of a transfer carrier provided by an embodiment of the present application is shown in FIG. 4.

[0041] Figure 5 A flowchart of another manufacturing method of a transfer carrier provided by an embodiment of the present application is shown in FIG. 5.

[0042] Figure 6 A process flowchart of another manufacturing method of a transfer carrier provided by an embodiment of the present application is shown in FIG. 6.

[0043] Figure 7 A structure schematic diagram of a transfer device provided by an embodiment of the present application is shown in FIG. 7.

[0044] Figure 8 A flowchart of a chip transfer method provided by an embodiment of the present application is shown in FIG. 8.

[0045] Figure 9 An application scenario schematic diagram of a chip transfer provided by an embodiment of the present application is shown in FIG. 9. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0047] The transfer carrier provided by the embodiments of the present application can be heated to a temperature of, for example, 110℃ after the transfer carrier adsorbs the chips. When the chips adsorbed by the transfer carrier are expanded by the expansion layer, the adhesion between the chips and the thermoplastic layer is greatly reduced due to the large flowability of the thermoplastic glue in the thermoplastic layer after being heated and softened, so that the chips can fall off on the driving substrate, thereby realizing the transfer of the chips by the transfer carrier, improving the risk of the chips being trapped in the glue layer and not being able to be pulled out and the glue being left on the chips, reducing the requirement for the device process, reducing the production cost, and solving the problem of damage to the chips caused by heat release.

[0048] The transfer carrier and the manufacturing method of the transfer carrier provided by the embodiments of the present application are described below in combination with the drawings.

[0049] Figure 1 A cross-sectional structure diagram of a transfer carrier provided by an embodiment of the present application is shown in FIG. 1. As shown in FIG. 1, the transfer carrier 10 includes a substrate 11, one side of the substrate 11 including a chip adsorption area 12; a first encapsulation layer 13 located around the chip adsorption area 12; a low-boiling expansion layer 14 covering the chip adsorption area 12; and a thermoplastic layer 15 located above the low-boiling expansion layer 14 and the first encapsulation layer 13. Figure 1

[0050] Specifically, the transfer carrier 10 includes the substrate 11, the first encapsulation layer 13, the low-boiling expansion layer 14, and the thermoplastic layer 15. The chip adsorption area 12 is included in the middle region of one side of the substrate 11, the low-boiling expansion layer 14 is located above the chip adsorption area 12, the first encapsulation layer 13 is arranged around the chip adsorption area 12, and the thermoplastic layer 15 is located above the low-boiling expansion layer 14 and the first encapsulation layer 13.

[0051] The material constituting the first encapsulation layer 13 includes at least one of epoxy resin, silicone glue, and polyurethane potting glue with good viscosity and sealing properties. The first encapsulation layer 13 is arranged around the chip adsorption area 12. On one hand, the first encapsulation layer 13 can adhere to the thermoplastic glue. On the other hand, the first encapsulation layer 13 can seal the low-boiling expansion layer 14 together with the thermoplastic layer 15, so as to isolate the low-boiling expansion layer 14 from water vapor and oxygen.

[0052] The thermoplastic glue constituting the thermoplastic layer 15 has a high viscosity at room temperature and can adsorb a chip. When heated to a temperature of, for example, 110°C, the thermoplastic glue softens and has a large flowability, resulting in a decrease in the viscosity of the thermoplastic glue and a decrease in the adsorption force between the chip and the thermoplastic glue. When the temperature returns to room temperature, the viscosity of the thermoplastic glue can recover, so that the thermoplastic glue can be repeatedly used.

[0053] The low-boiling expansion layer 14 can expand when heated and can apply a pushing force to the adsorbed chip. Thus, the transfer carrier 10 can adsorb a chip at room temperature. After the chip is adsorbed by the transfer carrier 10, the transfer carrier 10 is heated to a temperature of, for example, 110°C. The chip adsorbed by the transfer carrier 10 will be subjected to the pushing force applied by the expansion of the expansion layer, and the thermoplastic glue in the thermoplastic layer 15 will soften and have a large flowability when heated, resulting in a great decrease in the adhesion between the chip and the thermoplastic layer 15. The chip can fall on the driving substrate, so that the transfer of the chip by the transfer carrier 10 is realized.

[0054] ​The transfer carrier provided in this application includes a substrate with a chip adsorption area on one side; a first encapsulation layer surrounding the chip adsorption area; a low-boiling-point expansion layer covering the chip adsorption area; and a thermoplastic layer above the low-boiling-point expansion layer and the first encapsulation layer. Thus, after the chip is adsorbed by the transfer carrier, when the transfer carrier is heated to a temperature such as 110°C, the chip adsorbed by the transfer carrier is subjected to a pushing force exerted by the expansion layer during expansion, and the thermoplastic in the thermoplastic layer softens and becomes more fluid due to heat, resulting in a significant reduction in the adhesion between the chip and the thermoplastic layer. The chip can then detach from the driving substrate, thereby achieving the transfer of the chip by the transfer carrier. Compared with elastic mold micro-transfer technology, the present application's technical solution uses the expansion of the low-boiling-point expansion layer 14 to generate a pushing force on the chip, improving the risk of the chip becoming trapped in the adhesive layer and unable to be pulled out, as well as the risk of adhesive residue remaining on the chip. Compared with laser transfer technology, the present application's technical solution only requires heating to achieve chip transfer, with lower requirements for equipment and processes, reducing production costs. Since the heating temperature is within the chip's tolerance range, it solves the problem of heat release causing damage to the chip in laser transfer technology.

[0055] In some embodiments, continue to refer to Figure 1 The low-boiling-point expansion layer 14 includes a porous adsorption layer ( Figure 1 (not shown in the image) and low-boiling-point liquid organic materials injected into the porous adsorption layer.

[0056] Specifically, the materials constituting the porous adsorption layer include at least one of carbon powder, graphite, diatomaceous earth, and resin; the low-boiling-point liquid organic matter includes at least one of methyl ethyl ketone, ethyl acetate, trichloroethylene, and trifluoroacetic acid. Methyl ethyl ketone has a boiling point of 80°C, ethyl acetate has a boiling point of 77°C, trichloroethylene has a boiling point of 87°C, and trifluoroacetic acid has a boiling point of 72°C. Therefore, when the low-boiling-point expansion layer 14 is heated to a temperature such as 110°C, the low-boiling-point liquid organic matter in the porous adsorption layer vaporizes, causing the low-boiling-point expansion layer 14 to expand and exert a pushing force on the adsorbed chip. This facilitates the detachment of the chip adsorbed by the transfer carrier 10 from the driving substrate, thereby realizing the transfer of the chip by the transfer carrier 10.

[0057] In some embodiments, Figure 2 This is a schematic diagram of the cross-sectional structure of another transfer carrier plate provided in an embodiment of this application. (See attached diagram.) Figure 2 As shown, the transfer carrier 10 further includes a second encapsulation layer 16, disposed between the thermoplastic layer 15 and the low-boiling-point expansion layer 14, and located above the low-boiling-point expansion layer 14 and the first encapsulation layer 13 covered by the second encapsulation layer 16.

[0058] Specifically, a second encapsulation layer 16 can also be provided. First, the low-boiling-point expansion layer 14 and the first encapsulation layer 13 are covered with the second encapsulation layer 16, and then a thermoplastic layer 15 is covered on the second encapsulation layer 16. By providing the second encapsulation layer 16, compared to... Figure 1 The first encapsulation layer 13 is provided in the middle, which is beneficial to improve the adsorption force on the thermoplastic layer 15.

[0059] This application also provides a flowchart illustrating a method for manufacturing a transfer carrier. Figure 3 This is a flowchart illustrating a method for fabricating a transfer carrier plate according to an embodiment of this application.

[0060] like Figure 3 As shown, the method for fabricating the transfer carrier plate includes the following steps:

[0061] S301. A first encapsulation layer is formed around the chip adsorption area on one side of the substrate.

[0062] Specifically, Figure 4 A process flow diagram of a method for fabricating a transfer carrier provided in this application embodiment corresponds to... Figure 3 The manufacturing method steps shown include, Figure 3 S301 in the middle corresponds to Figure 4 S401 in the middle.

[0063] exist Figure 1 Based on, combined Figure 4 A pre-prepared substrate 11 can be provided, or the substrate 11 can be directly prepared. The material used to prepare the substrate 11 can be selected from glass, sapphire, a transparent and rigid polyimide film, or a high-temperature resistant polyester film. The prepared substrate 11 is cleaned and dried. Further, a chip adsorption region 12 is selected on one side of the substrate 11, and encapsulating adhesive is applied around the chip adsorption region 12 to form a first encapsulation layer 13 around the chip adsorption region 12.

[0064] The encapsulating adhesive can be at least one of epoxy resin, silicone, and polyurethane potting compound, which have good adhesion and sealing properties.

[0065] S302, A low-boiling-point expansion layer is formed in the chip adsorption region.

[0066] in, Figure 3 S302 in the middle corresponds to Figure 4 S402 in it. Specifically, continue to combine Figure 1 and Figure 4 A porous adsorption material is sprayed onto the chip adsorption region 12 to form a porous adsorption layer in the chip adsorption region 12. Figure 1 and Figure 4(Not shown in the image). After a porous adsorption layer is formed in the chip adsorption region 12, a low-boiling-point liquid organic material is injected into the porous adsorption layer to form a low-boiling-point expansion layer 14. Thus, a low-boiling-point expansion layer 14 is formed in the chip adsorption region 12.

[0067] The porous adsorbent material can be at least one of carbon powder, graphite, diatomaceous earth, and superabsorbent resin. The low-boiling-point liquid organic compound is at least one of methyl ethyl ketone, ethyl acetate, trichloroethylene, and trifluoroacetic acid. Methyl ethyl ketone has a boiling point of 80°C, ethyl acetate has a boiling point of 77°C, trichloroethylene has a boiling point of 87°C, and trifluoroacetic acid has a boiling point of 72°C. Therefore, when the low-boiling-point expansion layer is heated to a temperature such as 110°C, the low-boiling-point liquid organic compound in the porous adsorbent layer vaporizes, causing the low-boiling-point expansion layer to expand, which can generate a thrust on the chip adsorbed on the transfer carrier.

[0068] It should be noted that, Figure 3 S302 in the text can be before S301, or Figure 4 In step S402, the first encapsulation layer 13 can be formed around the chip adsorption region 12 before step S401, that is, after the low boiling point expansion layer 14 is formed in the chip adsorption region 12. This application embodiment does not specifically limit this.

[0069] S303, A thermoplastic layer is covered over the low-boiling-point expansion layer and the first encapsulation layer.

[0070] in, Figure 3 S303 in the middle corresponds to Figure 4 S403 in it. Specifically, continue to combine Figure 1 and Figure 4 After forming a first encapsulation layer 13 around the chip adsorption region 12 on one side of the substrate 11 and forming a low boiling point expansion layer 14 on the chip adsorption region 12, thermoplastic is sprayed or coated on the low boiling point expansion layer 14 and the first encapsulation layer 13, thereby covering the low boiling point expansion layer 14 and the first encapsulation layer 13 with a thermoplastic layer 15.

[0071] Thermoplastic adhesives have a high viscosity at room temperature, allowing them to adhere to chips and thus enabling chip pickup. When heated to a temperature such as 110°C, the viscosity of the thermoplastic decreases. After returning to room temperature, the viscosity of the thermoplastic adhesive recovers, allowing it to be reused.

[0072] The transfer carrier prepared by the manufacturing method provided in this application has a thermoplastic layer corresponding to the chip adsorption area that can adhere to the chip at room temperature. After the chip is adhered, the transfer carrier is heated to a temperature of, for example, 110°C. At this time, on the one hand, the thermoplastic in the thermoplastic layer softens and becomes more fluid due to the heat, resulting in a decrease in the viscosity of the thermoplastic and thus a decrease in the adsorption force on the chip. On the other hand, the low-boiling-point liquid organic matter in the low-boiling-point expansion layer vaporizes at a temperature of, for example, 110°C, causing the low-boiling-point expansion layer to expand, thereby exerting a pushing force on the adsorbed chip. As a result, the chip adsorbed on the transfer carrier is subjected to the pushing force exerted by the expansion of the low-boiling-point expansion layer, and the adhesion force between the chip and the thermoplastic layer is greatly reduced due to the softening of the thermoplastic due to the heat, allowing the chip to detach onto the driving substrate.

[0073] In some embodiments, Figure 5 This is a schematic flowchart illustrating another method for fabricating a transfer carrier 10 provided in an embodiment of this application. Figure 3 Based on, combined Figure 5 Before covering the thermoplastic layer above the boiling point expansion layer and the first encapsulation layer in S303, it also includes:

[0074] S3021. A second encapsulation layer is placed over the low-boiling-point expansion layer and the first encapsulation layer.

[0075] Specifically, Figure 6 A process flow diagram illustrating another method for fabricating a transfer carrier provided in an embodiment of this application. Figure 6 The process steps shown correspond to Figure 5 The production method and steps are shown.

[0076] in, Figure 6 S4021 in the middle corresponds to Figure 5 S3021 in [the context of the text]. Combined with [the context of the text]... Figure 2 and Figure 6 After forming a first encapsulation layer 13 around the chip adsorption region 12 on one side of the substrate 11 and a low-boiling-point expansion layer 14 on the chip adsorption region 12, encapsulating adhesive is first applied to the low-boiling-point expansion layer 14 and the first encapsulation layer 13 to form a second encapsulation layer 16, that is, the second encapsulation layer 16 is first covered on top of the low-boiling-point expansion layer 14 and the first encapsulation layer 13. Further, Figure 6 In S403, a thermoplastic layer 15 is covered above the low-boiling-point expansion layer 14 and the first encapsulation layer 13, that is, a thermoplastic layer 15 is covered on the second encapsulation layer 16. In conjunction with the above, by setting the second encapsulation layer 16, it is beneficial to improve the adsorption force on the thermoplastic layer 15.

[0077] Thus, between the process step S402 and the process step S403, a process step S4021 is added. Specifically, after the low-boiling-point expansion layer 14 is formed on the chip adsorption area 12, the process step S4021 is performed, and then the process step S403 is performed, i.e., the second packaging layer 16 is first coated on the low-boiling-point expansion layer 14 and the first packaging layer 13, and then the thermoplastic layer 15 is coated on the second packaging layer 16.

[0078] In some embodiments, after the second packaging layer is coated on the low-boiling-point expansion layer and the first packaging layer, the method further comprises:

[0079] The second packaging layer seals the low-boiling-point expansion layer.

[0080] Specifically, the low-boiling-point expansion layer is coated with the second packaging layer, and at this time, the liquid organic matter of the low-boiling-point expansion layer is completely sealed by the second packaging layer, so that the low-boiling-point expansion layer is sealed and isolated from water and oxygen.

[0081] In some embodiments, the thermoplastic layer corresponding to the chip adsorption area in the transfer carrier plate adheres the chip at room temperature.

[0082] Specifically, the thermoplastic layer corresponding to the chip adsorption area in the transfer carrier plate adheres the side of the chip away from the driving electrode at room temperature, so that the chip is picked up.

[0083] In some embodiments, the transfer carrier plate to which the chip is adhered is heated to a preset temperature, so that the chip falls off on the driving substrate.

[0084] Specifically, after the transfer carrier plate adheres the chip, i.e., the transfer carrier plate picks up the chip, the transfer carrier plate is heated to a preset temperature, for example, 110°C. At this time, the thermoplastic glue in the thermoplastic layer softens due to heating, resulting in a decrease in the viscosity of the thermoplastic glue, so that the adhesion of the chip to the thermoplastic layer is greatly reduced; and the low-boiling-point liquid organic matter in the low-boiling-point expansion layer vaporizes at a temperature of, for example, 110°C, resulting in expansion of the low-boiling-point expansion layer, so that a pushing force is applied to the adhered chip. Thus, the chip adhered to the transfer carrier plate falls off on the driving substrate due to the pushing force applied by the expansion of the low-boiling-point expansion layer and the greatly reduced adhesion of the chip to the thermoplastic layer due to the softening of the thermoplastic glue due to heating, so that the transfer of the chip is realized.

[0085] In some embodiments, the method for manufacturing the transfer carrier plate further comprises:

[0086] The ambient temperature is maintained to be less than or equal to 120°.

[0087] Specifically, after the transfer carrier plate adheres the chip, the transfer carrier plate is heated, and at this time, the environment in which the transfer carrier plate is maintained is less than or equal to 120°, for example, the transfer carrier plate is heated to 110°. In this way, while the expansion of the low-boiling-point expansion layer is realized, the heat damage to the chip caused by excessively high temperature can be avoided.

[0088] On the basis of the embodiments of the above application, the application further provides a transfer device. Figure 7 A structural schematic diagram of a transfer device provided by the application is shown in FIG. 2. As shown in the figure, the transfer device 20 comprises the transfer carrier plate 10 and a driving substrate 22 according to the embodiments of the above application. The driving electrodes 221 on the driving substrate 22 are used to fix the chips transferred by the transfer carrier plate 10, thus having the same or similar beneficial effects, which will not be repeated here. Figure 7

[0089] Specifically, the driving substrate 22 comprises the driving electrodes 221, which can be aligned with the chip electrodes. After the chips adsorbed on the transfer carrier plate 10 are separated from the transfer carrier plate 10, the chips can be fixed on the driving substrate 22 by the driving electrodes 221. Thus, the chips separated from the transfer carrier plate 10 can be fixed on the driving substrate 22 by the driving electrodes 221, so as to realize the transfer of the chips.

[0090] The application further provides a chip transfer method applied to the transfer device according to the embodiments of the above application. Figure 8 A flowchart of a chip transfer method provided by the application is shown in FIG. 3. As shown in the figure, the chip transfer method comprises the following steps: Figure 8

[0091] S801, adhering a chip by using a transfer carrier plate.

[0092] Specifically, in combination with the above, the chip is adhered by the transfer carrier plate provided by the application. The thermoplastic layer corresponding to the chip adsorption area in the transfer carrier plate adheres to the side of the chip away from the driving electrodes at room temperature, so as to pick up the chip.

[0093] S802, heating the transfer carrier plate adhering the chip to a preset temperature, so as to make the chip fall on the driving substrate.

[0094] Specifically, in combination with the above, after the transfer carrier plate adheres the chip, i.e., the transfer carrier plate picks up the chip, the transfer carrier plate is heated to a preset temperature, for example, 110°C. At this time, the thermoplastic glue in the thermoplastic layer softens due to heating, resulting in a decrease in the viscosity of the thermoplastic glue, so as to reduce the adsorption force of the chip; and the low-boiling-point liquid organic matter in the low-boiling-point expansion layer vaporizes at a temperature of, for example, 110°C, resulting in the expansion of the low-boiling-point expansion layer, so as to exert a pushing force on the adsorbed chip. Thus, the chip adhered by the transfer carrier plate is subjected to the pushing force exerted by the expansion of the low-boiling-point expansion layer, and the adhesion force between the chip and the thermoplastic layer is greatly reduced due to the softening of the thermoplastic glue caused by heating, so that the chip can fall on the driving substrate, thus realizing the transfer of the chip.

[0095] Exemplarily, Figure 9 ​​An application scenario of chip transfer provided by an embodiment of the present application is shown in FIG. 1. As shown in FIG. 1, the transfer carrier 10 picks up the chip 30 at room temperature, and then the transfer carrier 10 is heated, the adhesion of the chip 30 to the thermoplastic layer 15 is greatly reduced, and at the same time, the low-boiling-point liquid organic matter in the transfer carrier 10 vaporizes, expands in volume, the chip 30 is subjected to a pushing force, and the chip is separated from the transfer carrier 10, thereby realizing the transfer of the chip 30. Figure 9

[0096] Thus, the chip transfer method provided by the embodiment of the present application picks up the chip by the transfer carrier, and then heats the transfer carrier, the low-boiling-point liquid organic matter in the low-boiling-point expansion layer vaporizes and expands due to boiling, the chip is subjected to a pushing force due to the expansion of the low-boiling-point expansion layer, and the thermoplastic glue has greater flowability due to softening under heat, which leads to a great reduction in the adhesion of the chip to the transfer carrier, and the chip can fall off onto the driving substrate. The whole process is carried out at a relatively low temperature, for example, the temperature is generally less than 120°, but higher than the boiling point of the low-boiling-point liquid organic matter, thereby avoiding thermal damage to the chip. In addition, the low-boiling-point organic matter on the transfer carrier is in a liquid state at room temperature, vaporizes after heating, and returns to a liquid state after cooling; and the thermosetting glue can stick to the chip at room temperature, and the adhesion is greatly reduced after heating, and the adhesion can be restored after returning to room temperature. Therefore, the transfer carrier can be repeatedly used. Thus, compared with the elastic stamp micro-transfer printing technology, the low-boiling-point liquid organic matter in the technical solution of the present application generates a pushing force due to vaporization, which improves the risk that the chip is trapped in the glue layer and cannot be pulled out, and the risk that the glue is left on the chip. Compared with the laser transfer technology, the technical solution of the present application only needs to be heated to complete the transfer, and has a lower requirement for equipment and process, and can reduce production cost.

[0097] The technical features of the above embodiments can be combined in any manner. To make the description concise, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the present application.

[0098] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent. It should be pointed out that for ordinary skilled persons in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.​

Claims

1. A transfer carrier plate, characterized by, Comprising: a substrate having a chip-attachment area on one side thereof; a first encapsulation layer surrounding the chip-attachment area; a low-boiling expansion layer covering the chip-attachment area; the low-boiling expansion layer comprising a porous absorption layer and a low-boiling liquid organic material injected into the porous absorption layer; a thermoplastic layer overlying the low-boiling expansion layer and the first encapsulation layer.

2. The transfer substrate of claim 1, wherein, Further comprising: a second encapsulation layer disposed between the thermoplastic layer and the low-boiling expansion layer and overlying the low-boiling expansion layer and the first encapsulation layer.

3. A method of making a transfer carrier plate, the method comprising: Comprising: forming a first encapsulation layer surrounding a chip-attachment area on one side of a substrate; forming a low-boiling expansion layer over the chip-attachment area; including: forming a porous absorption layer over the chip-attachment area; injecting a low-boiling liquid organic material into the porous absorption layer to form a low-boiling expansion layer; 4. The method of claim 3, wherein overlying a thermoplastic layer over the low-boiling expansion layer and the first encapsulation layer. Before overlying a thermoplastic layer over the low-boiling expansion layer and the first encapsulation layer, further comprising:

5. The method of claim 3, wherein overlying a second encapsulation layer over the low-boiling expansion layer and the first encapsulation layer. After overlying a second encapsulation layer over the low-boiling expansion layer and the first encapsulation layer, further comprising:

6. The method of claim 3, wherein sealing the low-boiling expansion layer with the second encapsulation layer.

7. The method of claim 6, wherein adhering a chip to the thermoplastic layer corresponding to the chip-attachment area in the transfer carrier at room temperature.

8. The method of claim 3 to 7, wherein heating the transfer carrier with the adhered chip to a predetermined temperature to cause the chip to fall off onto the drive substrate. Further comprising: maintaining an ambient temperature less than or equal to 120°.

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