Reusable temporary support plate and reuse method thereof

Abstract

The invention relates to the technical field of semiconductor manufacturing, and discloses a reusable temporary support plate and a reuse method thereof, and the reusable temporary support plate comprises a support plate and a multi-layer composite membrane material attached to the surface of the support plate. The multi-layer composite film material sequentially comprises an outer release film I, a silica gel layer I, a base material layer, a silica gel layer II and an outer release film II from top to bottom, wherein the first silica gel layer is used for wrapping an LED chip electrode, and the second silica gel layer is used for being physically attached to a carrier plate; the method comprises the following steps: after cleaning and activating a carrier plate, attaching a film material and a wafer; stripping the substrate by using laser with the wavelength of 240 nm to 260 nm; transferring the chip through thermocompression bonding; and finally, the membrane material is physically torn off, and the carrier plate is cleaned for next use. According to the invention, the prefabricated composite film material is used for replacing liquid glue spin coating, and physical adsorption is used for replacing chemical bonding, so that the problem of glue residue on the surface of the carrier plate is solved, the carrier plate can be recycled for more than 10 times without damage, the cost is reduced, and the process yield is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, specifically to a reusable temporary carrier board and a method for reusing it. Background Technology

[0002] With the rapid development of Mini / Micro LED (miniature / micro-light-emitting diode) display technology, mass transfer technology has become a key bottleneck restricting its commercial mass production. In the mass transfer process, laser lift-off technology is typically used to peel the LED wafers grown on a sapphire substrate and transfer them to a temporary carrier for subsequent electrode fabrication or bonding to a driver backplane. Currently, the industry commonly uses liquid adhesives or liquid waxes, which are applied to the surface of a glass or sapphire carrier using a spin-coating process and then cured at high temperatures as a temporary bonding layer.

[0003] However, this traditional liquid spin coating process has significant drawbacks in practical applications. First, to meet the high-temperature resistance requirements of laser lift-off and subsequent processes, the liquid adhesive typically needs to be deeply cured at high temperatures. During this process, the polymer chains in the liquid adhesive readily react chemically with the hydroxyl groups on the surface of the glass or sapphire substrate, forming strong covalent bonds. This chemical bonding makes it difficult to completely remove the adhesive layer physically after the process, often requiring prolonged immersion in highly corrosive solvents or mechanical grinding to remove residual adhesive. This not only increases the difficulty of cleaning and the cost of chemical waste disposal, but more seriously, repeated cleaning or grinding with strong acids and alkalis damages the smoothness and gloss of the substrate surface, making expensive substrates (especially sapphire substrates) unusable or with extremely low reuse rates, significantly increasing manufacturing costs.

[0004] Furthermore, existing single-layer liquid adhesives are insufficient to meet the demands of multiple processes in terms of both structure and performance. Lacking a high-modulus physical framework, the cured adhesive layer has limited tensile strength and is prone to cohesive failure during peeling, leading to breakage and residue on the carrier or chip surface. Simultaneously, the thickness of liquid adhesive layers is difficult to control precisely at the micrometer level. If the layer is too thick, it is prone to deformation during high-temperature processes due to the high coefficient of thermal expansion of the polymer, affecting the overall thickness uniformity of the wafer and causing subsequent bonding alignment deviations. If the layer is too thin or lacks sufficient buffering capacity, it cannot effectively absorb the massive shock waves generated during laser peeling, easily causing displacement or even cracking of brittle LED chips. Moreover, existing adhesive formulations often lack precise control over the application time, making it easy for viscosity changes during coating to lead to a decrease in microscopic smoothness.

[0005] Finally, from the perspective of production efficiency and yield control, the existing liquid spin coating process requires a series of complex operations such as coating, leveling, and baking in a cleanroom, resulting in a long preparation cycle and extreme susceptibility to environmental temperature and humidity. On-site coating makes it difficult to ensure a highly consistent adhesive layer thickness across the entire board, often leading to uneven energy absorption during laser peeling due to uneven coating or incomplete curing, thus causing yield fluctuations. This over-reliance on on-site process conditions is no longer sufficient to meet the LED display industry's urgent needs for high output, high stability, and low cost. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a reusable temporary carrier and its reuse method, which solves the problem that in the existing LED chip mass transfer process, the temporary carrier forms an irreversible chemical bond with the carrier surface after the spin-coated liquid adhesive layer cures, making the adhesive layer difficult to remove and the carrier unable to be reused, thus resulting in excessively high carrier material costs in the mass transfer process.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] In a first aspect, the present invention provides a reusable temporary carrier plate, comprising: a carrier plate and a multilayer composite film material attached to the surface of the carrier plate. The multilayer composite film material comprises, from top to bottom, an outer release film one, a silicone layer one, a substrate layer, a silicone layer two, and an outer release film two;

[0009] The thickness of the outer release film one and the outer release film two is 45um to 55um;

[0010] The thickness of the silicone layer is 35µm to 45µm;

[0011] The thickness of the substrate layer is 10µm to 14µm;

[0012] The thickness of the silicone layer is 8µm to 12µm.

[0013] By adopting the above technical solution, and replacing the traditional in-situ spin-coating liquid adhesive process with a five-layer prefabricated composite film, the differences in physical modulus and interfacial chemical properties of the multi-layer materials enable residue-free peeling and reuse of the carrier plate, thereby reducing manufacturing costs. The specific mechanism is as follows:

[0014] Physical peeling mechanism and stress blocking: The substrate layer (polyethylene terephthalate) is located between silicone layer one and silicone layer two, playing a crucial role in physical barrier and stress transfer. During the recycling and tearing process, the 10µm to 14µm thick substrate layer provides sufficient tensile strength, preventing the silicone layer from breaking due to tearing force, ensuring that the film can be physically separated from the carrier surface in whole sheet form, and avoiding adhesive residue.

[0015] Differentiated functional layer design:

[0016] Silicone layer 2 (attachment layer): The thickness is controlled in the range of 8um to 12um, which is relatively thin and is mainly used for contact with the carrier. This thickness can fill the micro-undulations on the surface of the carrier and ensure tight adhesion, while also limiting thermal expansion deformation caused by excessive thickness, thereby ensuring that the overall thickness deviation of the wafer meets the micron-level processing requirements.

[0017] Silicone layer 1 (carrier layer): The thickness is controlled within the relatively thick range of 35um to 45um. This thickness design provides sufficient deformation space to effectively wrap the electrode structure of the LED chip during the mass transfer laser lift-off step, providing the necessary mechanical support and adhesion to prevent chip displacement.

[0018] Interface control of pre-formed film: Unlike liquid adhesives that undergo irreversible covalent bonding with the hydroxyl groups on the glass / sapphire surface after spin coating and high-temperature baking, this solution uses a pre-cured silicone layer II bonded to the carrier plate. The bonding strength primarily comes from van der Waals forces and physical adsorption, rather than strong chemical bonds. This physical bonding method ensures that the film can still be physically removed from the carrier plate after undergoing the high temperature and pressure of subsequent processes.

[0019] Preferably, the outer release film one and the outer release film two are made of polyethylene terephthalate coated with a fluorinated silane-modified organosilicon release agent; the substrate layer is made of polyethylene terephthalate; the silicone layer one is prepared from raw materials containing the following components: 90 to 110 parts of vinyl-terminated hydroxyl polydimethylsiloxane, 0.5 to 1.0 parts of platinum catalyst, 3 to 5 parts of hydrogen-containing silicone oil, and 0.02 to 0.04 parts of ethynylcyclohexanol; the silicone layer two is prepared from raw materials containing the following components: 90 to 110 parts of hydroxyl-terminated polydimethylsiloxane, 0.1 to 0.3 parts of dibutyltin dilaurate, and 2 to 4 parts of tetraethyl orthosilicate.

[0020] By adopting the above technical solution, and utilizing the differences in chemical properties between addition-type and condensation-type silicone rubber, the different requirements for chip carrying and substrate attachment are met respectively. The specific principle is as follows:

[0021] The addition curing mechanism of silicone layer one (temperature resistance and dimensional stability): Silicone layer one adopts an addition reaction system of vinyl polysiloxane and hydrogen-containing silicone oil under the action of platinum catalyst. With the addition of an appropriate amount of ethynylcyclohexanol as an inhibitor, the cross-linked network after curing exhibits extremely high thermal stability (temperature resistance ≥200℃) while ensuring the working life of the adhesive. During the high-temperature instant generated by laser exfoliation and the subsequent hot-press bonding process (150℃), silicone layer one does not undergo thermal decomposition or flow, ensuring the absolute accuracy of the LED chip position.

[0022] The condensation curing mechanism of silicone layer two (adhesion control and peelability): Silicone layer two adopts a condensation reaction system of hydroxyl-terminated polysiloxane and tetraethyl orthosilicate under the action of a tin catalyst. By controlling the amount of crosslinking agent (tetraethyl orthosilicate), the crosslinking density is precisely adjusted. During the reaction, silanol groups and ethoxy groups condense to form silicon-oxygen bonds and release ethanol molecules. The surface energy of the cured system is moderate, and it has good initial adhesion to inorganic material surfaces (glass, sapphire). Moreover, this adhesion is pressure-sensitive and will not increase excessively over time, thus ensuring that it can be completely peeled off after the process is completed.

[0023] Surface modification of release film: The release agent modified with fluorinated silane greatly reduces the surface energy of the release film surface, ensuring that the release film will not damage the smoothness of the silicone layer surface during peeling, and avoiding micro-defects on the silicone layer surface that may affect the subsequent bonding accuracy.

[0024] Preferably, the multilayer composite film is prepared by the following process: coating the inner surface of the substrate layer with the second silicone layer material and drying and curing it at a temperature of 110°C to 130°C for 2 to 4 minutes; coating the outer surface of the substrate layer with the first silicone layer material and drying and curing it at a temperature of 140°C to 160°C for 3 to 5 minutes; attaching the second outer release film to the surface of the cured second silicone layer using a hot press roller, and attaching the first outer release film to the surface of the cured first silicone layer using a hot press roller to form the multilayer composite film and then winding it up; and curing the wound film at a temperature of 35°C to 45°C and a relative humidity of 55% to 65% for 20 to 28 hours.

[0025] By adopting the above technical solution and through a stepwise thermosetting and low-temperature curing process, internal stress was eliminated and the cross-linking network was improved.

[0026] Stepped temperature curing: Curing temperatures of 110-130℃ and 140-160℃ are used for silicone layer 2 and silicone layer 1 respectively, matching their respective activation energies. The inner layer is cured at a low temperature first, followed by the outer layer at a high temperature, effectively preventing curling or wrinkling of the polyethylene terephthalate substrate layer due to uneven heating, thus ensuring the high flatness of the membrane material.

[0027] Low-temperature curing post-treatment: The reaction of condensation-type silicone (silicone layer two) is an equilibrium process. Curing at 35-45℃ and 55%-65% humidity for 20-28 hours utilizes trace amounts of moisture in the environment to promote the hydrolysis and further condensation of residual alkoxy groups, ensuring the complete chemical reaction of silicone layer two. This step is crucial; it eliminates residual small molecules in the silicone layer, preventing these substances from volatilizing and causing bubble formation during subsequent high-temperature chip manufacturing processes, thus ensuring yield.

[0028] Preferably, the carrier is a circular carrier, and the carrier material is selected from glass, sapphire, and silicon wafers; the diameter of the carrier ranges from 4 inches to 12 inches, the thickness of the carrier ranges from 1 millimeter to 2 millimeters, and the surface roughness of the carrier is less than 0.5 nm.

[0029] By adopting the above technical solution, the surface morphology parameters of the carrier plate are defined. The surface roughness of less than 0.5 nm, combined with the silicone layer, forms a tight contact at the microscopic level, maximizing the van der Waals force interaction area. This allows for the achievement of the shear strength required for laser exfoliation without the use of chemical adhesives. At the same time, a smooth surface is also a necessary physical condition for achieving residue-free exfoliation.

[0030] Secondly, the present invention provides a method for reusing a reusable temporary carrier board, comprising the following steps:

[0031] S1. Provide a carrier plate, and perform surface cleaning, drying and surface activation treatment on the carrier plate;

[0032] S2. Remove the outer release film 2 of the multilayer composite film material, attach the silicone layer 2 to the surface of the carrier board, and remove the outer release film 1 of the multilayer composite film material to attach the LED chip wafer electrode surface to the surface of the silicone layer 1.

[0033] S3. Use a laser to peel off the LED chip wafer substrate, leaving the LED chip on one surface of the silicone layer. Align and bond the carrier plate with the target carrier plate with the pre-coated adhesive layer, and transfer the LED chip to the target carrier plate by hot pressing.

[0034] S4. After the LED chip transfer is completed, the multilayer composite film is physically peeled off from the edge of the carrier board. The carrier board after peeling off the multilayer composite film is cleaned and dried to obtain a clean carrier board for the next use.

[0035] By adopting the above technical solution, a complete closed-loop process integrating surface modification, physical adhesion, energy stripping, and physical recovery was established, achieving lossless recycling of the carrier plate. Its core innovative mechanism is as follows:

[0036] Physical adsorption replaces chemical bonding: Traditional methods rely on the formation of covalent bonds between the liquid adhesive and the carrier plate during curing, requiring the destruction of chemical bonds for removal. In this method, in step S2, the low modulus of the silicone layer 2 in the pre-fabricated film is utilized to achieve a tight bond with the carrier plate under pressure via van der Waals forces. This physical bonding force is sufficient to resist the shock wave generated by laser ablation in step S3. However, in the ablation direction of step S4 (typically 90 or 180 degrees), interfacial stress concentration makes the film easily detach from the carrier plate surface.

[0037] Non-destructive restoration of the carrier surface: Since the second silicone layer has been pre-cured, its polymer network structure is stable and will not penetrate into the micropores of the carrier surface. Therefore, after removing the film in step S4, there are no uncured low-molecular-weight residues or difficult-to-remove cross-linked polymers on the carrier surface. It can be restored to its initial surface energy state (Ra<0.5nm) with just routine cleaning, thus avoiding the loss of carrier thickness and surface flatness caused by repeated polishing or strong acid and alkali cleaning.

[0038] Process compatibility design: This method seamlessly integrates with existing laser exfoliation and thermosetting bonding processes. The film material, acting as an energy buffer layer, absorbs and disperses excess heat under laser irradiation, protecting the carrier from thermal shock damage and extending the carrier's physical lifespan.

[0039] Preferably, in step S1, the surface cleaning specifically involves: first, ultrasonic cleaning with acetone at a frequency of 35kHz to 45kHz and a temperature of 20℃ to 30℃ for 8 to 12 minutes; then, ultrasonic cleaning with isopropanol at a frequency of 35kHz to 45kHz and a temperature of 20℃ to 30℃ for 8 to 12 minutes; and finally, rinsing with deionized water for 4 to 6 minutes. In step S4, the cleaning of the carrier plate after removing the multilayer composite film is performed using the same process as the surface cleaning in step S1.

[0040] By adopting the above technical solution, surface contaminants were completely removed using the principle of stepwise solvent replacement.

[0041] Like dissolves like and stepwise displacement: Acetone, as a highly polar organic solvent, can effectively dissolve grease, fingerprints, or trace organic oligomers on the surface of the substrate; then isopropanol is used for cleaning, which can dissolve residual acetone and is also miscible with water, acting as a bridge between the organic phase and the aqueous phase; finally, deionized water is used to thoroughly rinse away isopropanol and inorganic ions.

[0042] Ultrasonic cavitation effect: At a specific frequency of 35kHz to 45kHz, micron-sized bubbles generated in the cleaning fluid burst on the surface of the carrier plate, generating microjets that can peel off nano-sized particles adsorbed in the micro-pits of the carrier plate, ensuring that the carrier plate achieves atomic-level cleanliness, which is the basis for ensuring the subsequent physical adhesion strength.

[0043] Preferably, in step S1, the drying process is completed by baking on a hot plate at 110°C to 130°C for 10 to 20 minutes, followed by purging with nitrogen; the surface activation process is completed by using O2 plasma at a power of 90W to 110W and a pressure of 40Pa to 60Pa for 2 to 4 minutes.

[0044] By adopting the above technical solution, physical adhesion is enhanced through dehumidification and surface energy modification:

[0045] Deep dehydration prevents gas explosion: The baking temperature of 110℃ to 130℃ is higher than the boiling point of water, which can completely remove water molecules adsorbed on the surface of the substrate. Without this step, the residual moisture will vaporize and expand instantly at the high temperature of laser stripping, causing local bulging of the film material and affecting the positioning accuracy of the chip.

[0046] Plasma hydroxylation modification: O2 plasma bombards the surface of glass, sapphire, or silicon wafers, removing residual organic carbon through oxidation and introducing a high density of hydrophilic hydroxyl groups onto the inorganic surface. Although this invention does not rely on chemical bonding, the high density of surface hydroxyl groups improves surface wettability, allowing the silicone layer 2 to spread more fully during bonding, maximizing the intermolecular contact area and thus enhancing physical adsorption.

[0047] Preferably, in step S2, the second silicone layer is attached to the surface of the carrier plate at room temperature and under a pressure of 0.3 MPa to 0.6 MPa for 25 to 35 seconds; the electrode surface of the LED chip wafer is attached to the surface of the first silicone layer at room temperature and under a pressure of 0.3 MPa to 0.6 MPa for 25 to 35 seconds.

[0048] By adopting the above technical solution, uniform bonding was achieved by utilizing the viscoelastic rheological properties of silicone material:

[0049] Pressure-induced rheology: The pressure range of 0.3 MPa to 0.6 MPa is precisely controlled. Too low a pressure will not be able to expel interfacial air, resulting in voids; too high a pressure will crush the brittle compound semiconductor wafer. Under this pressure, the silicone layer with a specific cross-linking density undergoes elastic deformation, filling the microscopic undulations on the substrate surface.

[0050] Stress relaxation: A holding time of 25 to 35 seconds allows polymer chain segments to rearrange and relax, releasing the internal stress generated during the bonding process and preventing the membrane material from springing back and lifting at the edges after the pressure is removed.

[0051] Preferably, in step S3, the laser ablation uses a wavelength selected from 248 nm and 266 nm, with an energy density of 0.8 J / cm². 2Up to 1J / cm 2 The LED chip wafer substrate is removed by laser; the LED chip is transferred to the target carrier by thermo-press bonding for 2 to 4 minutes at a temperature of 140°C to 160°C and a pressure of 0.15 MPa to 0.25 MPa; in step S4, the drying process is completed by nitrogen purging for 4 to 6 minutes.

[0052] By adopting the above technical solution, high chip transfer yield and high carrier board recycling efficiency are ensured:

[0053] Energy window control: Lasers in the 248nm or 266nm band are selected. Ultraviolet light in this band is efficiently absorbed by the gallium nitride substrate interface, at a wavelength of 0.8 J / cm². 2 Up to 1J / cm 2 The energy density is set to the optimal window, allowing the energy to penetrate the substrate and focus at the interface between the gallium nitride epitaxial layer and the substrate. This causes a thermal decomposition reaction of the gallium nitride at the interface, generating metallic gallium and nitrogen gas, thereby achieving separation of the chip from the substrate. Simultaneously, after the energy is absorbed by the film material, the temperature resistance of the silicone layer ensures that it will not carbonize or melt, thus protecting the chip electrode surface from contamination.

[0054] Rheological matching of thermocompression bonding: At 140°C to 160°C, the adhesive coating on the target substrate reaches a molten and flowing state, while the silicone layer of this invention remains elastic and solid. This modulus difference allows the chip to be easily demolded from the film surface and embedded in the adhesive layer of the target substrate, achieving high-precision selective transfer.

[0055] This invention provides a reusable temporary carrier plate and a method for reusing it. It has the following beneficial effects:

[0056] 1. This invention uses a pre-fabricated five-layer composite film to replace the traditional liquid adhesive spin coating process. By utilizing the pre-curing properties of the bottom silicone layer (silicone layer two), it ensures that there is only physical adsorption between the bottom layer and the glass or sapphire substrate. This avoids the problem in the traditional process where the liquid adhesive chemically bonds with the hydroxyl groups on the substrate surface under high-temperature baking and cannot be removed. Therefore, after the chip transfer process is completed, the composite film can be completely and physically peeled off from the substrate surface without any adhesive residue. It can be reused for the next time with only conventional solvent cleaning, and can be reused more than 10 times.

[0057] 2. This invention effectively blocks tensile stress during film peeling by setting a high-modulus polyethylene terephthalate substrate layer in the middle of the film material, preventing adhesive layer breakage and residue. At the same time, the thickness of the silicone layer two in contact with the carrier is strictly controlled within a relatively thin range of 8µm to 12µm, reducing deformation caused by polymer thermal expansion during high-temperature processing and ensuring the stability of the overall thickness deviation of the carrier. Combined with the effective wrapping of the chip electrodes by the thicker silicone layer one, it provides buffer protection under the high-energy impact of laser peeling, preventing chip displacement or cracking. In addition, the introduction of an ethynylcyclohexanol inhibitor into the silicone layer one effectively controls the processing time of the adhesive, ensuring the consistency and microscopic flatness of the film coating.

[0058] 3. This invention uses roll-shaped dry film for immediate application, which shortens the preparation time of a single carrier plate. The pre-made film material has completed thickness and cross-linking control at the factory, eliminating yield fluctuations caused by uneven coating and incomplete baking on the production site. The set laser wavelength (248nm or 266nm) and energy density parameters are fully compatible with existing mainstream laser stripping equipment, requiring no additional equipment modification investment. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the structure of a multilayer composite membrane material provided in an embodiment of the present invention;

[0060] Figure 2 This is a flowchart illustrating a method for reusing a reusable temporary carrier board, as provided in an embodiment of the present invention.

[0061] Among them, 1. Outer release film one; 2. Silicone layer one; 3. Substrate layer; 4. Silicone layer two; 5. Outer release film two. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, preparation examples, embodiments, comparative examples, and test examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] Preparation Examples 1-3:

[0064] Preparation Example 1:

[0065] Reference Appendix Figure 1 This preparation example provides a multilayer composite film material, which consists of the following layers from top to bottom: outer release film 1 (50um), silicone layer 2 (40um), substrate layer 3 (12um), silicone layer 4 (10um), and outer release film 5 (50um).

[0066] The preparation method of multilayer composite membrane materials includes the following steps:

[0067] Preparation of raw materials for silicone layer 24: Weigh 100 parts of hydroxyl-terminated polydimethylsiloxane, 0.2 parts of dibutyltin dilaurate, 3 parts of tetraethyl orthosilicate and 60 parts of toluene, mix them evenly and perform vacuum degassing treatment to obtain silicone layer 24 adhesive solution.

[0068] Preparation of raw materials for silicone layer 1-2: Weigh 100 parts of vinyl-terminated polydimethylsiloxane, 0.8 parts of platinum catalyst, 4 parts of hydrogen-containing silicone oil (hydrogen content 1.0%), 0.03 parts of ethynylcyclohexanol and 40 parts of toluene, mix them evenly and perform vacuum degassing treatment to obtain silicone layer 1-2 adhesive solution.

[0069] Coating and curing: A polyethylene terephthalate substrate layer 3 with a thickness of 12 μm is provided. Silicone layer 2 4 is coated on the inner surface of the substrate layer 3, and the dry film thickness is controlled to be 10 μm. The substrate layer is then dried and cured in an oven at 120°C for 3 minutes. Subsequently, silicone layer 1 2 is coated on the outer surface of the substrate layer 3, and the dry film thickness is controlled to be 40 μm. The substrate layer is then dried and cured in an oven at 150°C for 4 minutes.

[0070] Lamination and curing: The outer release film 2 5 with a thickness of 50 μm is laminated to the surface of the cured silicone layer 2 4 using a hot press roller, and the outer release film 1 with a thickness of 50 μm is laminated to the surface of the cured silicone layer 2 using a hot press roller. The film roll is then rolled up to form a film roll. The film roll is placed at 40°C and 60% relative humidity for 24 hours to obtain a multilayer composite film material.

[0071] Preparation Example 2:

[0072] Reference Appendix Figure 1 This preparation example provides a multilayer composite film material, which consists of the following layers from top to bottom: outer release film 1 (45um), silicone layer 2 (35um), substrate layer 3 (10um), silicone layer 4 (8um), and outer release film 5 (45um).

[0073] The preparation method of multilayer composite membrane materials includes the following steps:

[0074] Preparation of raw materials for silicone layer 24: Weigh 90 parts of hydroxyl-terminated polydimethylsiloxane, 0.1 parts of dibutyltin dilaurate, 2 parts of tetraethyl orthosilicate and 50 parts of toluene, mix them evenly and perform vacuum degassing treatment to obtain silicone layer 24 adhesive solution.

[0075] Preparation of raw materials for silicone layer 1-2: Weigh 90 parts of vinyl-terminated polydimethylsiloxane, 0.5 parts of platinum catalyst, 3 parts of hydrogen-containing silicone oil (hydrogen content 1.0%), 0.02 parts of ethynylcyclohexanol and 30 parts of toluene, mix them evenly and perform vacuum degassing treatment to obtain silicone layer 1-2 adhesive solution.

[0076] Coating and curing: A polyethylene terephthalate substrate layer 3 with a thickness of 10 μm is provided. Silicone layer 2 4 is coated on the inner surface of the substrate layer 3, and the dry film thickness is controlled to be 8 μm. The substrate layer 4 is then dried and cured in an oven at 110°C for 2 minutes. Subsequently, silicone layer 1 2 is coated on the outer surface of the substrate layer 3, and the dry film thickness is controlled to be 35 μm. The substrate layer 2 is then dried and cured in an oven at 140°C for 3 minutes.

[0077] Lamination and curing: The outer release film 2 5 with a thickness of 45 μm is laminated to the surface of the cured silicone layer 2 4 using a hot press roller, and the outer release film 1 with a thickness of 45 μm is laminated to the surface of the cured silicone layer 2 using a hot press roller. The film roll is then rolled up to form a film roll. The film roll is placed at 35°C and 55% relative humidity for 20 hours to obtain a multilayer composite film material.

[0078] Preparation Example 3:

[0079] Reference Appendix Figure 1 This preparation example provides a multilayer composite film material, which consists of the following layers from top to bottom: outer release film 1 (55um), silicone layer 2 (45um), substrate layer 3 (14um), silicone layer 4 (12um), and outer release film 5 (55um).

[0080] The preparation method of multilayer composite membrane materials includes the following steps:

[0081] Preparation of raw materials for silicone layer 24: Weigh 110 parts of hydroxyl-terminated polydimethylsiloxane, 0.3 parts of dibutyltin dilaurate, 4 parts of tetraethyl orthosilicate and 70 parts of toluene, mix them evenly and perform vacuum degassing treatment to obtain silicone layer 24 adhesive solution.

[0082] Preparation of raw materials for silicone layer 1-2: Weigh 110 parts of vinyl-terminated polydimethylsiloxane, 1.0 part of platinum catalyst, 5 parts of hydrogen-containing silicone oil (hydrogen content 1.0%), 0.04 parts of ethynylcyclohexanol and 50 parts of toluene, mix them evenly and perform vacuum degassing treatment to obtain silicone layer 1-2 adhesive solution.

[0083] Coating and curing: A polyethylene terephthalate substrate layer 3 with a thickness of 14 μm is provided. Silicone layer 2 4 is coated on the inner surface of the substrate layer 3, and the dry film thickness is controlled to be 12 μm. The substrate layer is then dried and cured in an oven at 130°C for 4 minutes. Subsequently, silicone layer 1 2 is coated on the outer surface of the substrate layer 3, and the dry film thickness is controlled to be 45 μm. The substrate layer is then dried and cured in an oven at 160°C for 5 minutes.

[0084] Lamination and curing: The outer release film 2 5 with a thickness of 55 μm is laminated to the surface of the cured silicone layer 2 4 using a hot press roller, and the outer release film 1 with a thickness of 55 μm is laminated to the surface of the cured silicone layer 2 using a hot press roller. The film roll is then rolled up to form a film roll. The film roll is placed at a temperature of 45℃ and a relative humidity of 65% for 28 hours to obtain a multilayer composite film material.

[0085] Examples 1-3:

[0086] Example 1:

[0087] Reference Appendix Figure 2 This embodiment provides a method for reusing a reusable temporary carrier plate, using the multilayer composite film obtained in Preparation Example 1, applied to a glass carrier plate with a diameter of 6 inches and a thickness of 1.5 mm, including the following steps:

[0088] S1. Carrier plate surface cleaning, drying and activation treatment

[0089] Provide a 6-inch diameter glass substrate and clean it using cleaning equipment in the following stages:

[0090] The first stage uses acetone for ultrasonic cleaning at a frequency of 40kHz and a temperature of 25℃ for 10 minutes.

[0091] The second stage uses isopropanol for ultrasonic cleaning at a frequency of 40kHz, a temperature of 25℃, and a cleaning time of 10 minutes.

[0092] The third stage involves rinsing with deionized water for 5 minutes.

[0093] After cleaning, place the glass substrate on a hot plate at 120°C and bake for 15 minutes, followed by drying with nitrogen purging.

[0094] Subsequently, the dried glass substrate surface was activated using O2 plasma at a power of 100W, a chamber pressure of 50Pa, and a processing time of 3 minutes.

[0095] S2, Adhesion of multilayer composite film to chip

[0096] Take the multilayer composite film prepared in Preparation Example 2, peel off the outer release film 5, and attach the exposed silicone layer 4 to the surface of the glass substrate after step S1. The attachment conditions are: room temperature, pressure head pressure 0.5 MPa, and holding time 30 seconds.

[0097] Subsequently, the outer release film 1 of the multilayer composite film is peeled off, and the electrode surface of the LED chip wafer is attached to the exposed silicone layer 2. The attachment conditions are: room temperature, pressure head pressure of 0.5MPa, and holding time of 30 seconds.

[0098] S3, Laser Lifting and Chip Transfer

[0099] A 248nm laser was incident from the back (non-coated) side of the glass substrate, with the laser energy density controlled at 0.9J / cm². 2 This separates the LED chip substrate from the LED chip; at this point, the adhesive force of the silicone layer 2 is used to support the peeled-off LED chip.

[0100] The glass substrate carrying the LED chip is aligned and bonded to the target substrate coated with a pre-coated layer. The LED chip is then transferred to the target substrate by thermo-press bonding. The bonding conditions are: temperature 150℃, pressure 0.2MPa, duration 3 minutes.

[0101] S4, Carrier Plate Recycling and Regeneration

[0102] After the LED chip transfer is completed, the remaining multi-layer composite film is completely removed from the edge of the glass substrate using a physical film-removing machine, thus separating the film from the glass substrate.

[0103] After removing the film, the glass carrier is cleaned using the same cleaning process as the first to third stages in step S1 (acetone ultrasonic / isopropanol ultrasonic / water washing). After cleaning, nitrogen is used to purge for 5 minutes to obtain a clean glass carrier, which can then be reused.

[0104] Example 2:

[0105] Reference Appendix Figure 2 This embodiment provides a method for reusing a reusable temporary substrate. The method utilizes the multilayer composite film prepared in Example 2, applied to a sapphire substrate with a diameter of 4 inches and a thickness of 1 mm, and includes the following steps:

[0106] S1. Carrier plate surface cleaning, drying and activation treatment

[0107] Provide a 4-inch diameter sapphire substrate and clean it using cleaning equipment in the following stages:

[0108] The first stage uses acetone for ultrasonic cleaning at a frequency of 35kHz, a temperature of 20℃, and a cleaning time of 12 minutes.

[0109] The second stage uses isopropanol for ultrasonic cleaning at a frequency of 35kHz, a temperature of 20℃, and a cleaning time of 12 minutes.

[0110] The third stage involves rinsing with deionized water for 6 minutes.

[0111] After cleaning, the sapphire substrate is placed on a hot plate at 110°C and baked for 20 minutes, followed by drying with nitrogen purging.

[0112] Subsequently, the surface of the dried sapphire substrate was activated using O2 plasma at a power of 90W, a chamber pressure of 40Pa, and a processing time of 4 minutes.

[0113] S2, Adhesion of multilayer composite film to chip

[0114] Take the multilayer composite film prepared in Preparation Example 1, peel off the outer release film 5, and attach the exposed silicone layer 4 to the surface of the sapphire substrate after step S1. The attachment conditions are: room temperature, pressure head pressure 0.3 MPa, and holding time 35 seconds.

[0115] Subsequently, the outer release film 1 of the multilayer composite film is peeled off, and the electrode surface of the LED chip wafer is attached to the exposed silicone layer 2. The attachment conditions are: room temperature, pressure head pressure of 0.3MPa, and holding time of 35 seconds.

[0116] S3, Laser Lifting and Chip Transfer

[0117] A 266nm wavelength laser was incident from the back of a sapphire substrate, with the laser energy density controlled at 0.8 J / cm². 2 This separates the LED chip substrate from the LED chip; at this point, the adhesive force of the silicone layer 2 is used to support the peeled-off LED chip.

[0118] The sapphire substrate carrying the LED chip is aligned and bonded to the target substrate coated with a pre-coated layer. The LED chip is then transferred to the target substrate by thermo-press bonding. The bonding conditions are: temperature 140℃, pressure 0.15MPa, and duration 4 minutes.

[0119] S4, Carrier Plate Recycling and Regeneration

[0120] After the LED chip transfer is completed, the remaining multilayer composite film is completely removed from the edge of the sapphire substrate using a physical film-removing machine, separating the film from the sapphire substrate. The sapphire substrate after the film is removed is then cleaned using the same cleaning process as the first to third stages in step S1 (acetone ultrasonic / isopropanol ultrasonic / water washing). After cleaning, the substrate is purged with nitrogen for 6 minutes to obtain a clean sapphire substrate, which can then be reused.

[0121] Example 3:

[0122] Reference Appendix Figure 2 This embodiment provides a method for reusing a reusable temporary carrier board. The method utilizes the multilayer composite film prepared in Preparation Example 3, applied to a silicon wafer carrier board with a diameter of 12 inches and a thickness of 2 mm, and includes the following steps:

[0123] S1. Carrier plate surface cleaning, drying and activation treatment

[0124] Provide a 12-inch diameter silicon wafer carrier and clean it using cleaning equipment in the following stages:

[0125] The first stage uses acetone for ultrasonic cleaning at a frequency of 45kHz, a temperature of 30℃, and a cleaning time of 8 minutes.

[0126] The second stage uses isopropanol for ultrasonic cleaning at a frequency of 45kHz, a temperature of 30℃, and a cleaning time of 8 minutes.

[0127] The third stage involves rinsing with deionized water for 4 minutes.

[0128] After cleaning, the silicon wafer substrate is placed on a hot plate at 130°C and baked for 10 minutes, followed by drying with nitrogen purging.

[0129] Subsequently, the surface of the dried silicon wafer carrier was activated using O2 plasma with a power of 110W, a chamber pressure of 60Pa, and a processing time of 2 minutes.

[0130] S2, Adhesion of multilayer composite film to chip

[0131] Take the multilayer composite film prepared in Preparation Example 3, peel off the outer release film 5, and attach the exposed silicone layer 4 to the surface of the silicon wafer carrier after step S1. The attachment conditions are: room temperature, pressure head pressure 0.6 MPa, and holding time 25 seconds.

[0132] Subsequently, the outer release film 1 of the multilayer composite film is peeled off, and the electrode surface of the LED chip wafer is attached to the exposed silicone layer 2. The attachment conditions are: room temperature, pressure head pressure of 0.6MPa, and holding time of 25 seconds.

[0133] S3, Laser Lifting and Chip Transfer

[0134] A 248nm wavelength laser was incident from the back of a silicon substrate, with the laser energy density controlled at 1.0 J / cm². 2 This separates the LED chip substrate from the LED chip; at this point, the adhesive force of the silicone layer 2 is used to support the peeled-off LED chip.

[0135] The silicon wafer carrier carrying the LED chip is aligned and bonded to the target carrier coated with a pre-coated layer. The LED chip is then transferred to the target carrier by thermo-press bonding. The bonding conditions are: temperature 160℃, pressure 0.25MPa, duration 2 minutes.

[0136] S4, Carrier Plate Recycling and Regeneration

[0137] After the LED chip transfer is completed, the remaining multilayer composite film is completely removed from the edge of the silicon wafer carrier using a physical film-removing machine, thus separating the film from the silicon wafer carrier.

[0138] After the film material is removed, the silicon wafer carrier is cleaned. The cleaning process is the same as the first to third stages in step S1 (acetone ultrasonic / isopropanol ultrasonic / water washing). After cleaning, nitrogen gas is used to purge for 4 minutes to obtain a clean silicon wafer carrier, which can then be reused.

[0139] Comparative Examples 1-4:

[0140] Comparative Example 1:

[0141] Compared with Example 1, the difference is that: this comparative example does not use multilayer composite film material, but instead directly applies liquid temporary bonding wax to the surface of glass substrate through spin coating process (controlling the thickness to 50um), and then bakes and cures it at 120°C before attaching the chip; and in step S4, the substrate is not physically peeled off during substrate recycling, but is immersed in a special organic adhesive remover for 2 hours and mechanically brushed to remove the residual adhesive layer, and the remaining steps are the same as in Example 1.

[0142] Comparative Example 2:

[0143] Compared with Example 1, the difference is that the composite film used in this comparative example does not contain substrate layer 3 (polyethylene terephthalate film). Its structure from top to bottom is as follows: outer release film 1, silicone layer 2, silicone layer 4, and outer release film 5. When preparing this film, the adhesive solution of silicone layer 2 is directly applied to the surface of the cured silicone layer 4 for curing. The other raw material formulations, the thickness of each silicone layer, and the usage steps are the same as in Example 1.

[0144] Comparative Example 3:

[0145] Compared with Example 1, the difference is that in the multilayer composite membrane material used in this comparative example, the raw material formulation of the silicone layer 4 in contact with the carrier plate is replaced with the same addition-curing silicone formulation as silicone layer 2 (i.e., vinyl-terminated polydimethylsiloxane, platinum catalyst, hydrogen-containing silicone oil and inhibitor, with the proportions of each component being the same as silicone layer 2). In addition, the curing temperature of silicone layer 4 is adjusted to 150°C during the membrane preparation process. The remaining membrane structural parameters and usage steps are the same as in Example 1.

[0146] Comparative Example 4:

[0147] Compared with Example 1, the difference is that in the multilayer composite membrane material used in this comparative example, the dry film thickness of the silicone layer 4 is adjusted to 50 μm, while the remaining membrane structure, raw material formulation and usage steps are the same as in Example 1.

[0148] Test example:

[0149] This test case aims to verify the overall performance of the above embodiments and comparative methods in practical applications, particularly the reusability of the carrier, the ability to restore surface cleanliness, and the process stability during chip transfer.

[0150] Test content:

[0151] Total thickness deviation test: Using a non-contact laser thickness gauge with an accuracy of 0.1μm, nine measurement points distributed in a star pattern were selected on the surface of the carrier plate after the film was applied or the adhesive was applied. The thickness of the bare carrier plate before film application and the total thickness of the assembly after film application were measured respectively. The actual thickness of the adhesive layer / film layer at each point was calculated, and the difference between the maximum thickness value and the minimum thickness value was taken as the total thickness deviation value.

[0152] Chip transfer yield testing: For the target substrate after laser lift-off and chip transfer steps, an automated optical inspection system is used to scan the chip array. The number of chips exhibiting breakage, cracks, or positional misalignment exceeding 5μm is counted. ), calculate its position in the total number of chips ( The proportion of the chip in the formula is used to determine the chip transfer yield. .

[0153] Surface Residue (Contact Angle) Test: For recycled carrier plates after physical film removal and cleaning, the contact angle was measured using an optical contact angle meter with a seated drop method. Deionized water was used as the probe liquid, with a droplet volume of 2 μL. Droplets were placed at five locations on the carrier plate surface, and the solid-liquid contact angle values ​​were read after standing for 3 seconds and averaged. A contact angle greater than 15° was considered to indicate the presence of organic residue, and greater than 60° was considered to indicate the presence of adhesive residue.

[0154] Carrier reusability test: Steps S1 to S4 are repeated on the same carrier. After each cycle, the surface contact angle is measured and microscopic defects are inspected. The test is stopped when residues that cannot be removed by cleaning (contact angle >15°), scratches with a depth greater than 0.5 μm, or edge defects appear on the carrier surface. The number of complete cycles completed before failure is recorded.

[0155] Test data:

[0156] Table 1. Summary of Comprehensive Performance Test Data for Each Group

[0157] Group Total thickness deviation of adhesive layer / film layer (μm) Chip transfer yield (%) Initial contact angle (°) Contact angle after cleaning (°) (1st cycle) Contact angle after cleaning (°) (10th cycle) Maximum number of times the carrier board can be reused. Example 1 1.8 99.84 6.5 6.8 7.2 17 Example 2 1.9 99.52 8.2 8.4 9.1 14 Example 3 2.6 99.15 5.8 6.1 6.9 11 Comparative Example 1 4.8 94.70 6.5 35.6 N / A 1 Comparative Example 2 2.8 90.23 6.5 78.4 N / A 2 Comparative Example 3 1.7 N / A 6.5 >100 (Cannot be peeled off) N / A 0 Comparative Example 4 11.4 87.60 6.5 7.0 7.5 12

[0158] Note: N / A indicates that no further testing was conducted due to substrate failure or low yield; Comparative Example 3 could not be physically peeled off due to chemical bonding, so the transfer yield could not be calculated.

[0159] Conclusion Analysis:

[0160] According to the test results in Table 1, the multilayer composite film and supporting process used in Examples 1 to 3 can achieve multiple reuses of the carrier while ensuring high-precision chip transfer yield. The mechanism is that the silicone layer 4 on the contact side of the carrier uses a condensation-type organosilicon formulation. In this formulation system, hydroxyl groups form physical adsorption and hydrogen bonding with hydroxyl groups or oxides on the surface of the carrier, rather than permanent chemical covalent bonds. This physical adsorption force is sufficient to fix the carrier during the laser peeling process. However, after the peeling process, the interfacial bonding force can be destroyed by physical tearing. With conventional solvent cleaning, the surface of the carrier can be restored to its initial hydrophilic state (contact angle <10°), thus avoiding the carrier surface contamination problem caused by penetration and cross-linking residue in the traditional liquid adhesive solution (Comparative Example 1).

[0161] In the embodiment, the substrate layer 3 (polyethylene terephthalate) plays a crucial role in barrier and mechanical support within the system. Comparative data shows that when substrate layer 3 is missing (Comparative Example 2), the membrane material cannot withstand tensile stress during physical removal and breaks, resulting in a large amount of colloid residue remaining on the carrier surface. This not only increases the difficulty of cleaning but also directly leads to a significant reduction in the number of times the carrier can be reused. Simultaneously, the presence of the polyethylene terephthalate substrate layer 3 effectively blocks the migration of unreacted small molecules from the upper addition-cured silicone (silicone layer 2) to the carrier surface, ensuring the separation characteristics of the carrier-membrane interface. Conversely, if the contact layer is changed to an addition-cured formulation (Comparative Example 3), the platinum catalytic system induces hydrosilylation or silanol condensation chemical bonding between the silicone and the carrier surface at high temperatures, causing the membrane material to fail to peel off completely, resulting in the carrier being unusable.

[0162] Furthermore, the thickness control of silicone layer 4 has a significant impact on process stability. In this embodiment, by limiting the thickness of silicone layer 4 to a specific micrometer range (8-12 μm), the thermal expansion effect during high-temperature processes was effectively suppressed. Data from Comparative Example 4 shows that when the thickness of the bottom silicone layer increases to 50 μm, although the reusability of the substrate is not affected, the high thermal expansion coefficient of the silicone material results in significant Z-axis deformation under the high-temperature environment of laser lift-off and hot-press bonding, leading to an increase in the total thickness deviation. This, in turn, causes a coplanarity deviation in the chip array, ultimately resulting in a significant decrease in chip transfer yield. This demonstrates that this application achieves a balance between substrate reusability cost and process yield through a multi-layer structure design, utilizing a thin-layer condensation-type silicone layer for adsorption, an intermediate substrate layer 3 for rigid support, and an upper addition-type silicone layer for heat-resistant adhesion.

Claims

1. A reusable temporary carrier board, characterized in that, include: A carrier plate and a multilayer composite film material attached to the surface of the carrier plate; The multilayer composite film material consists of, from top to bottom, an outer release film (1), a silicone layer (2), a substrate layer (3), a silicone layer (4), and an outer release film (5). The outer release film one (1) and the outer release film two (5) have a thickness of 45 μm to 55 μm; The thickness of the first silicone layer (2) is 35 μm to 45 μm; The thickness of the substrate layer (3) is 10 μm to 14 μm; The thickness of the second silicone layer (4) is 8 μm to 12 μm.

2. A reusable temporary carrier plate according to claim 1, characterized in that, The outer release film one (1) and the outer release film two (5) are made of polyethylene terephthalate coated with fluorinated silane modified organosilicon release agent; The substrate layer (3) is made of polyethylene terephthalate; The first silicone layer (2) is prepared from a raw material containing the following components: 90 to 110 parts vinyl-terminated hydroxyl polydimethylsiloxane, 0.5 to 1.0 parts platinum catalyst, 3 to 5 parts hydrogen-containing silicone oil, and 0.02 to 0.04 parts ethynylcyclohexanol; The second silicone layer (4) is prepared from raw materials containing the following components: 90 to 110 parts of hydroxyl-terminated polydimethylsiloxane, 0.1 to 0.3 parts of dibutyltin dilaurate, and 2 to 4 parts of tetraethyl orthosilicate.

3. A reusable temporary carrier plate according to claim 1, characterized in that, The multilayer composite film material is prepared by the following process: The silicone layer 2 (4) material is coated on the inner surface of the substrate layer (3) and dried and cured at a temperature of 110°C to 130°C for 2 to 4 minutes. The silicone layer (2) material is coated on the outer surface of the substrate layer (3) and dried and cured at a temperature of 140°C to 160°C for 3 to 5 minutes. The outer release film 2 (5) is bonded to the surface of the cured silicone layer 2 (4) by a hot press roller, and the outer release film 1 (1) is bonded to the surface of the cured silicone layer 1 (2) by a hot press roller to form the multilayer composite film and then rolled up. The wound film material is cured at a temperature of 35°C to 45°C and a relative humidity of 55% to 65% for 20 to 28 hours.

4. A reusable temporary carrier plate according to claim 1, characterized in that, The carrier plate is a circular carrier plate, and the carrier plate material is selected from one of glass, sapphire and silicon wafers; The diameter of the carrier plate ranges from 4 inches to 12 inches, the thickness of the carrier plate ranges from 1 millimeter to 2 millimeters, and the surface roughness of the carrier plate is less than 0.5 nm.

5. A method for reusing a reusable temporary carrier plate, characterized in that, The application of a reusable temporary carrier plate according to any one of claims 1-4 includes the following steps: S1. Provide a carrier plate, and perform surface cleaning, drying and surface activation treatment on the carrier plate; S2. Remove the outer release film 2 (5) of the multilayer composite film material, attach the silicone layer 2 (4) to the surface of the carrier plate, and remove the outer release film 1 (1) of the multilayer composite film material, attach the LED chip wafer electrode surface to the surface of the silicone layer 1 (2). S3. Use a laser to peel off the LED chip wafer substrate, leaving the LED chip on the surface of the silicone layer (2), align the carrier plate with the target carrier plate with the pre-coated adhesive coating, and transfer the LED chip to the target carrier plate by hot pressing bonding; S4. After the LED chip transfer is completed, the multilayer composite film is physically peeled off from the edge of the carrier board. The carrier board after peeling off the multilayer composite film is cleaned and dried to obtain a clean carrier board for the next use.

6. The method for reusing a reusable temporary carrier plate according to claim 5, characterized in that, In step S1, the surface cleaning specifically includes: First, use acetone to ultrasonically clean for 8 to 12 minutes at a frequency of 35 kHz to 45 kHz and a temperature of 20°C to 30°C. Then, ultrasonic cleaning was performed for 8 to 12 minutes using isopropanol at a frequency of 35 kHz to 45 kHz and a temperature of 20°C to 30°C. Finally, rinse with deionized water for 4 to 6 minutes.

7. The method for reusing a reusable temporary carrier plate according to claim 5, characterized in that, In step S1, the drying process is completed by baking on a hot plate at 110°C to 130°C for 10 to 20 minutes, followed by purging with nitrogen. The surface activation treatment is completed by using O2 plasma at a power of 90W to 110W and a pressure of 40Pa to 60Pa for 2 to 4 minutes.

8. The method for reusing a reusable temporary carrier plate according to claim 5, characterized in that, In step S2, the silicone layer 2 (4) is attached to the surface of the carrier plate at room temperature and under a pressure of 0.3 MPa to 0.6 MPa for 25 to 35 seconds. The LED chip wafer electrode surface is attached to the surface of the silicone layer (2) at room temperature and under a pressure of 0.3 MPa to 0.6 MPa for 25 to 35 seconds.

9. A method for reusing a reusable temporary carrier plate according to claim 5, characterized in that, In step S3, the laser ablation uses a wavelength selected from 248 nm and 266 nm, with an energy density of 0.8 J / cm². 2 Up to 1J / cm 2 Laser stripping of the LED chip wafer substrate; The LED chip is transferred to the target substrate by thermocompression bonding for 2 to 4 minutes under conditions of 140°C to 160°C and 0.15MPa to 0.25MPa.

10. A method for reusing a reusable temporary carrier plate according to claim 5, characterized in that, In step S4, the cleaning of the carrier plate after removing the multilayer composite film is performed using the same process as the surface cleaning in step S1. In step S4, the drying process is completed by purging with nitrogen for 4 to 6 minutes.

Images