A method for transferring micro-leds based on chemical dynamic bond seal

Abstract

The application discloses a method for transferring Micro-LED based on chemical dynamic bond stamping, and the Micro-LED transfer method is realized by a polyborosiloxane (PBS) polymer stamp containing a dynamic boron-oxygen bond, a Micro-LED array chip based on a weakened structure and a target hetero-substrate based on glue spraying adhesion treatment. The application utilizes the property that the polyborosiloxane (PBS) polymer stamp exhibits a viscous flow state under low pressure stress stimulation and exhibits a solid state under high peeling stress, realizes a high switching ratio of the grabbing force of the Micro-LED, and thus realizes efficient pickup and placement of the Micro-LED. The transfer method is simple and fast, has the characteristics of high-efficiency transfer of wafer-level small-size Micro-LED chips, and has a very broad application prospect in the fields of Micro-LED display, flexible optoelectronics and photoelectric information communication.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic integration, specifically relating to a method for transferring Micro-LEDs based on chemical dynamic bond stamping. Background Technology

[0002] Micro-LEDs have outstanding advantages in brightness, energy consumption, and lifespan, making them promising for applications in near-eye displays, digital communications, and integrated optoelectronics, and attracting widespread attention from researchers.

[0003] The key to fabricating Micro-LED optoelectronic devices is to integrate a massive number of Micro-LEDs grown on a wafer substrate onto a heterogeneous substrate to meet the different needs of various application scenarios.

[0004] Monolithic integration technology can directly integrate heterogeneous substrates onto wafers on which a large number of Micro-LED chips have grown. However, when the size of Micro-LED devices is larger than 12 inches, or when it is necessary to integrate Micro-LEDs onto flexible substrates, monolithic integration technology cannot be implemented. This has also restricted the further development and application of Micro-LED optoelectronic devices.

[0005] Mass transfer technology based on Micro-LEDs can selectively pick up single or multiple Micro-LEDs from the growth substrate, and can also be printed on different heterogeneous substrates. Compared with this, it has a high degree of integration freedom and has become a key research focus for experts and scholars in recent years.

[0006] Currently, the methods used to achieve mass transfer of Micro-LEDs include:

[0007] 1. Transfer method based on PDMS stamp

[0008] Taking advantage of the characteristic that the maximum adhesion of PDMS to Micro-LEDs varies with the peeling rate, when a Micro-LED needs to be extracted, PDMS is quickly picked up. At this time, the adhesion of PDMS to the Micro-LED is greater than that of the Micro-LED to the original substrate, thus realizing the pickup of the Micro-LED by the PDMS stamp. When printing the Micro-LED onto the target substrate, it is only necessary to slowly peel off the PDMS and the Micro-LED. At this time, the adhesion of PDMS to the Micro-LED is less than that of the Micro-LED to the target substrate, thus completing the transfer of the Micro-LED. In addition, when placing the Micro-LED with the PDMS stamp, a laser-assisted method can be used to effectively improve the transfer efficiency and rate of the Micro-LED.

[0009] 2. Electrostatic Micro-LED Transfer Method

[0010] The transfer head employs a bipolar structure, which utilizes the electrostatic attraction and repulsion generated by applying positive and negative voltages. When it is necessary to pick up an LED from the substrate, a positive voltage is applied to one silicon electrode, at which point the electrode generates electrostatic attraction to the Micro-LED, which is sufficient to attract the Micro-LED to the transfer head. When it is necessary to place the LED in a predetermined position, a negative voltage is applied to the silicon electrode, at which point the transfer head generates electrostatic repulsion to the Micro-LED, and the Micro-LED is placed on the target substrate, thus realizing the transfer of the Micro-LED.

[0011] 3. Micro-LED transfer method based on fluid self-assembly

[0012] Micro-LED transfer printing is a technology that utilizes the characteristics of Micro-LED's own gravity and geometry to automatically assemble Micro-LED devices into the designated areas of the design through fluid drive.

[0013] While the above methods can meet the basic requirements of Micro-LED transfer printing, issues such as transfer yield, transfer speed, and cost result in high prices for Micro-LED devices, significantly hindering their further market penetration. Therefore, industry experts are actively researching and developing new materials and methods for Micro-LED transfer printing, hoping to overcome the problems of low yield, slow speed, and high cost.

[0014] 1. Photosensitive polymer stamps for Micro-LED transfer

[0015] By adding a photoreactive polymer to an adhesive stamp, the stamp's adhesiveness is used to pick up a wafer-level Micro-LED array. When the stamp mixed with the photosensitive polymer is irradiated with ultraviolet light, the irradiated polymer undergoes a chemical change, causing that part of the stamp to lose its adhesiveness, thereby achieving selective transfer of Micro-LEDs.

[0016] 2. Thermal memory epoxy resin stamp for Micro-LED transfer

[0017] By adding a photoreactive polymer to an adhesive stamp, the stamp's adhesiveness is used to pick up a wafer-level Micro-LED array. When the stamp mixed with the photosensitive polymer is irradiated with ultraviolet light, the irradiated polymer undergoes a chemical change, causing that part of the stamp to lose its adhesiveness, thereby achieving selective transfer of Micro-LEDs.

[0018] 3. Transfer stamps containing thermally expanding microspheres enable Micro-LEDs.

[0019] By mixing thermally expanding microspheres into an adhesive stamp, the micro-LEDs are first picked up by the stamp's adhesiveness. Then, the stamp containing the thermally expanding microspheres is irradiated with a laser. The microspheres then expand due to heat, and the micro-LEDs are pushed off the stamp, thus achieving programmable micro-LED array transfer.

[0020] Despite the great potential of these technologies in transferring Micro-LEDs, strict process conditions and methods still need to be improved for different approaches to achieve high yield, low cost and ultra-fast Micro-LED transfer. Summary of the Invention

[0021] Currently, Micro-LEDs have become a research hotspot in the field of optoelectronic information display due to their high brightness, low power consumption, and ultra-long lifespan. However, because Micro-LEDs are smaller than 100 micrometers, and a single high-definition display device typically requires tens of millions of Micro-LED chips, current technology struggles to conveniently and quickly transfer massive numbers of Micro-LEDs onto heterogeneous substrates. This invention aims to provide a method for transferring Micro-LEDs using a chemically dynamic bond stamp. This method comprises a polyborosiloxane (PBS) polymer stamp containing dynamic boron-oxygen bonds, a Micro-LED array chip based on a weakened structure, and a target heterogeneous substrate treated with adhesive spraying. This invention utilizes the properties of the PBS polymer stamp—exhibiting a viscous flow state under low compressive stress and a solid state under high peel stress—to achieve an ultra-high gripping switching ratio for Micro-LEDs, thereby enabling highly efficient pickup and placement of Micro-LEDs. The transfer method is simple and fast, characterized by high-efficiency transfer of wafer-level small-sized Micro-LED chips.

[0022] To achieve the above objectives, the present invention adopts the following technical solution:

[0023] This invention provides a method for stamping Micro-LEDs based on dynamic chemical bonds. A PBS stamp is laid flat on the surface of a Micro-LED array on a raw substrate. A pressure of ≤1N is applied to ensure the PBS stamp conformally adheres to each Micro-LED pixel in the array. Then, a peeling speed of ≥20cm / s is used to separate the PBS stamp adhered to the Micro-LED array from the raw substrate, obtaining a PBS stamp with the Micro-LED array attached. The PBS stamp with the Micro-LED array attached is then laid flat on a target substrate. After sufficient contact, the Micro-LED array adheres to the target substrate. Finally, a peeling speed of 5–10cm / s is used to separate the PBS stamp from the Micro-LED array.

[0024] The transfer method of this invention uses a polyborosiloxane (PBS) polymer containing dynamic boron-oxygen bonds as a stamp. The inventors discovered that the PBS polymer stamp exhibits viscous flow properties under low-pressure stress, allowing it to conformally fit each small-sized Micro-LED chip upon contact. Utilizing the solid-state properties of the PBS stamp under high peel stress, it generates a high gripping force on the Micro-LED during rapid pickup, achieving high-efficiency pickup and placement of Micro-LEDs. This transfer method is simple and fast, characterized by high-efficiency transfer of wafer-level small-sized Micro-LED chips. It has broad application prospects in Micro-LED displays, flexible optoelectronics, and optoelectronic information communication.

[0025] The inventors discovered that, compared to PMDS stamps which utilize surface van der Waals forces to transfer micro-LEDs via their lower surface, involving only the interaction of two surfaces, PBS stamps, due to their dynamic fluidity, can achieve sufficient fluid conformation during micro-LED transfer. The micro-LEDs are embedded within the PBS stamp, enhancing the overall van der Waals adhesion between the stamp and the micro-LEDs. Furthermore, the fluidity of PBS effectively overcomes the problem of low transfer yield caused by uneven force when transferring wafer-level micro-LED arrays using PDMS stamps.

[0026] However, during the stamp transfer process, the pressure of the PBS stamp and the Micro-LED array needs to be effectively controlled. If the pressure is ≤0.1N, it will take at least 30 minutes to achieve conformal bonding between the PBS and the Micro-LED array. If the transfer rate is too low, it will affect the transfer yield. If the pressure is too high, it will cause the conformal bonding rate between the PBS and the Micro-LED array to be too fast, resulting in the Micro-LED array being completely embedded in the PBS, which will reduce the yield of subsequent PBS printing of Micro-LEDs.

[0027] In a preferred embodiment, the Young's modulus of the PBS stamp is 0.01–3 MPa. Due to the presence of dynamic chemical bonds, its Young's modulus varies with external stress stimulation, ranging from 0.01 to 3 MPa. The higher the Young's modulus of PBS, the more pronounced the solid properties of the material; conversely, the lower the Young's modulus of PBS, the more pronounced the fluid properties of the material.

[0028] Of course, if the Young's modulus of the PBS stamp is not within the above range when stimulated by external stress, such as when the flow properties are too obvious, the array after picking up the stamp will exhibit severe distortion during the picking process, reducing the transfer efficiency.

[0029] In a preferred embodiment, the preparation process of the PBS stamp is as follows: boric acid is dissolved in methanol to obtain a boric acid solution, then hydroxyl-terminated polydimethylsiloxane (PDMS-OH) is added to the boric acid solution to obtain a mixture, reacted, and the solvent is removed to obtain the final product.

[0030] In a further preferred embodiment, the molecular weight of the hydroxyl-terminated polydimethylsiloxane is 500 to 50,000, preferably 2,000 to 10,000.

[0031] In a further preferred embodiment, the mass ratio of boric acid to methanol is 1:30 to 50.

[0032] In a further preferred embodiment, the mass ratio of boric acid to hydroxyl-terminated polydimethylsiloxane is 1:5 to 10.

[0033] The inventors discovered that PDMS is the main chemical framework of PBS, and the tensile properties and viscosity of PBS are determined by the molecular weight of PDMS. The role of boric acid is to introduce dynamic boron-oxygen chemical bonds into PBS. These dynamic chemical bonds determine the flow properties of PBS printing. In other words, within a certain range, the higher the proportion of boric acid, the stronger the flowability of PBS. With the synergistic effect of the molecular weight of the hydroxyl-terminated polydimethylsiloxane and the proportion of boric acid, the resulting PBS stamp has the most suitable Young's modulus, and its viscous flow and solid-state change properties are optimal, ultimately achieving the best transfer yield.

[0034] In a further preferred embodiment, the reaction temperature is 50-80℃ and the reaction time is 2-4h.

[0035] In actual operation, a mixture is obtained in a mold, heated in a water bath, and the reaction is carried out by stirring. After the reaction is completed, excess solvent is removed, and the block taken out of the mold is a polyborosiloxane (PBS) polymer stamp with boron-oxygen dynamic chemical bonds.

[0036] In a preferred embodiment, the original substrate is a wafer silicon substrate, and the wafer silicon substrate and the Micro-LED array are first subjected to a weakening treatment to obtain a Micro-LED array with a weakened structure.

[0037] In a further preferred embodiment, in the weakened structure Micro-LED array, the contact area between the silicon pillar and the Micro-LED array is 1 to 5% of the total bottom area of ​​the Micro-LED array.

[0038] In a further preferred embodiment, the weakening process is as follows: first, ICP etching is used to obtain a silicon pillar-supported Micro-LED array, and then an alkaline solution is used to etch the silicon pillar side to form a weakened structure Micro-LED.

[0039] More preferably, the alkaline solution is a KOH solution, wherein the mass fraction of KOH in the KOH solution is 30-45%.

[0040] More preferably, the corrosion temperature is 40-60℃ and the corrosion time is 6-8 minutes.

[0041] Using chemical etching to weaken the contact between Micro-LED and the silicon wafer substrate is a relatively simple and economical way to achieve Micro-LED transfer.

[0042] In a preferred embodiment, a PBS stamp is laid flat on the surface of the Micro-LED array on the original substrate, and then a pressure of 0.5 to 1 N is applied for 1 to 3 minutes to ensure that the PBS stamp conformally fits to each Micro-LED pixel in the Micro-LED array.

[0043] By controlling the pressure and duration within the above range, the Micro-LED printing capability will be the strongest. If the duration is too long, the Micro-LED will be completely embedded in the PBS, which will reduce the subsequent Micro-LED printing capability.

[0044] In a preferred embodiment, the PBS stamp is held with wide tweezers and separated from the original substrate at a peeling speed of 20–25 cm / s.

[0045] PBS stamps exhibit high viscous flow properties under low-speed shearing. At this point, the adhesive force of PBS on the Micro-LED is insufficient to separate the Micro-LED from the PET, thereby achieving high-efficiency transfer printing of small-sized Micro-LED arrays.

[0046] In a preferred embodiment, the target substrate is a PET flexible substrate, and a layer of mist adhesive is first sprayed onto the PET flexible substrate using 3M 75# spray adhesive.

[0047] Before transferring the PBS stamp with the Micro-LED array to the target substrate, a layer of atomized adhesive can be sprayed to enhance the adhesion of the target substrate.

[0048] In a preferred embodiment, the method of transferring Micro-LEDs using a stamp transfers Micro-LED pixels with a size ≥ 5 μm and an array density ≤ 2000 PPI.

[0049] The method of this invention can achieve a minimum transfer size of 5µm and a maximum transfer chip array density of 2000 PPI. The transfer yield reaches 95%.

[0050] Beneficial effects

[0051] The Micro-LED transfer method provided by this invention is realized by a polyborosiloxane (PBS) polymer stamp containing dynamic boron-oxygen bonds, a Micro-LED array chip based on a weakened structure, and a target heterogeneous substrate based on adhesive spraying.

[0052] Compared to traditional PDMS stamp transfer methods for Micro-LEDs, this invention utilizes a unique PBS stamp containing boron oxide dynamic bonds to achieve high-yield transfer of wafer-level ultra-small Micro-LED arrays in a simplified and extremely fast manner. This technology has achieved the transfer of Micro-LED microdisplays with a diagonal of 0.39 inches, a single pixel density of 5 micrometers, and a pixel density of 2000 PPI, achieving a transfer yield of 90%. Furthermore, this invention's PBS stamp can achieve Micro-LED transfer on three-dimensional curved surfaces, potentially enabling high integration of Micro-LED optoelectronic devices, expanding their application prospects, and deepening their application value. Attached Figure Description

[0053] Figure 1 : A diagram of the PBS stamp structure used for transfer printing;

[0054] Figure 2 : A diagram of the Micro-LED array structure after weakening treatment;

[0055] Figure 3 : Conformal transfer diagram. Detailed Implementation

[0056] Example 1

[0057] A method for transferring Micro-LEDs based on chemical dynamic bond stamps.

[0058] The first step involved mixing boric acid and methanol solution at a mass ratio of 1:50. The mixture was then magnetically stirred for 1 hour in a water bath at room temperature and pressure to ensure complete dissolution of the boric acid in the methanol solution. Subsequently, 10 grams of hydroxyl-terminated polydimethylsiloxane (PDMS-OH) with a molecular weight of 2000 was added to 100 grams of the boric acid-methanol mixture, and the mixture was stirred at high speed in a 50°C water bath for 3 hours to ensure sufficient cross-linking and the formation of boron-oxidative dynamic bonds. The resulting viscous mixture was poured into a circular glass mold and placed in a fume hood overnight to remove most of the methanol solution. Afterward, it was vacuum dried at 60°C for 6 hours to obtain a polyborosiloxane (PBS) polymer with boron-oxidative dynamic bonds. The Young's modulus of the PBS was 0.01–3 MPa.

[0059] The second step involves fabricating a Micro-LED array with a single pixel size ranging from 5 to 80 micrometers. A 1-micrometer-high silicon pillar is formed by etching GaN to Si(111) substrate using ICP. The silicon pillar is then immersed in a 45% KOH solution at 60°C for 7 minutes to form a weakened Micro-LED structure.

[0060] The third step involves laying the obtained PBS stamp with boron-oxidative dynamic bonds flat on the surface of the Micro-LED chip, and then gently rolling the PBS stamp with a mounting roller at a pressure of 1N and a speed of 3cm / s for 3 minutes to ensure that it makes full conformal contact with each Micro-LED pixel.

[0061] The fourth step involves using wide tweezers to hold the PBS stamp and separating it from the Micro-LED chip substrate at a peeling speed of 20 cm / s. At this point, the PBS stamp exhibits high solid-state properties, and the gripping force formed by its conformal interaction with the Micro-LED is sufficient to separate the Micro-LED from the Si substrate, thereby achieving high-efficiency pickup of the Micro-LED array.

[0062] The fifth step involves laying the PBS stamp with the Micro-LED array attached flat on a PET flexible substrate that has undergone adhesive spraying. A paper-mounting roller is used to gently press and flatten the PBS stamp, ensuring full contact with the PET substrate. Wide tweezers are then used to hold the PBS stamp and peel it off at a speed of 5 cm / s to separate the stamp from the Micro-LED chip substrate. The PBS stamp exhibits high viscous flow properties under low-speed shearing; at this point, the adhesive force of the PBS to the Micro-LED is insufficient to separate the Micro-LED from the PET. This achieves the transfer printing of a Micro-LED array with a diagonal size of 0.39 inches, a single pixel size of 5 micrometers, and a pixel density of 2000 ppi, with a pickup yield of 99.99% and an overall transfer yield of 90%.

[0063] Comparative Example 1

[0064] Take 10g of hydroxyl-terminated polydimethylsiloxane (PDMS-OH) with a molecular weight of 2000, add 1g of PDMS-OH curing agent, and stir at high speed in a water bath at 50℃ for 3 hours to ensure a complete crosslinking reaction. Pour the resulting viscous mixture into a circular glass mold and vacuum dry at 60℃ for 6 hours to obtain a PDMS stamp.

[0065] For comparison with Example 1, except for the seal synthesis, the other implementation methods are the same as in Example 1.

[0066] The transfer results showed that when the PDMS-based stamp was used to transfer a Micro-LED array with a diagonal size of 0.39 inches, a single pixel size of 5 micrometers, and a pixel density of 2000ppi, the pickup yield was 40% and the overall transfer yield was 20%.

[0067] Comparative Example 2

[0068] For comparison with Example 1, the first and second steps in this implementation process are the same as the first and second steps in Example 1.

[0069] The third step involves laying the obtained PBS stamp with boron oxidation dynamic bonds flat on the surface of the Micro-LED chip, and then gently rolling the PBS stamp with a mounting roller at a pressure of 100N and a speed of 3cm / s for 30 minutes to ensure that it makes full conformal contact with each Micro-LED pixel.

[0070] The fourth step involves using wide tweezers to hold the PBS stamp and separating it from the Micro-LED chip substrate at a peeling speed of 20 cm / s. At this point, the PBS stamp exhibits high solid-state properties, and the gripping force formed by its conformal interaction with the Micro-LED is sufficient to separate the Micro-LED from the Si substrate, thereby achieving high-efficiency pickup of the Micro-LED array with a pickup efficiency of 100%.

[0071] The fifth step involves laying the PBS stamp with the Micro-LED array attached flat on a PET flexible substrate that has undergone adhesive spraying. A paper-mounting roller is used to gently press and flatten the PBS stamp, ensuring full contact with the PET substrate. Wide tweezers are then used to hold the PBS stamp and peel it off at a speed of 5 cm / s, thus achieving the transfer printing of a Micro-LED array with a diagonal size of 0.39 inches, a single pixel size of 5 micrometers, and a pixel density of 2000 ppi. However, due to the excessively long conformal pressure and time required when picking up the Micro-LED array, the Micro-LEDs are completely embedded in the PBS stamp. Although the pickup yield can reach 100%, the Micro-LEDs are difficult to print onto the adhesive-enhanced PET substrate, resulting in an overall yield of only 5%.

[0072] Comparative Example 3

[0073] The first step involved mixing boric acid and methanol solution at a mass ratio of 1:50. The mixture was then magnetically stirred for 1 hour in a water bath at room temperature and pressure to ensure complete dissolution of the boric acid in the methanol solution. Subsequently, 10 grams of hydroxyl-terminated polydimethylsiloxane (PDMS-OH) with a molecular weight of 100,000 was added to 100 grams of the boric acid-methanol mixture, and the mixture was stirred at high speed in a 50°C water bath for 3 hours to ensure sufficient cross-linking and the formation of boron-oxidative dynamic bonds. The resulting viscous mixture was poured into a circular glass mold and placed in a fume hood overnight to remove most of the methanol solution. Afterward, it was vacuum-dried at 60°C for 6 hours to obtain a polyborosiloxane (PBS) polymer with boron-oxidative dynamic bonds.

[0074] To compare with Example 1, except for the molecular weight of the PDMS synthesized in the first step, the other steps and implementation methods are the same as in Example 1.

[0075] The results showed that PBS synthesized from hydroxyl-terminated polydimethylsiloxane (PDMS-OH) with a molecular weight of 100,000 achieved 100% efficiency in picking up a Micro-LED array with a diagonal size of 0.39 inches, a single pixel size of 5 micrometers, and a pixel density of 2000 ppi. However, due to its Young's modulus of only 0.1 MPa during curing, it exhibited extremely high flow properties, resulting in severe distortion of the array during the picking process. Furthermore, the high molecular weight of PDMS-OH increased the viscosity of PBS, leading to a Micro-LED printing efficiency of only 3% on the PET substrate.

Claims

1. A method for transferring Micro-LEDs based on chemical dynamic bonding stamps, characterized in that: A PBS stamp is laid flat on the surface of the Micro-LED array on the original substrate. A pressure of ≤1N is applied to ensure that the PBS stamp conformally adheres to each Micro-LED pixel in the Micro-LED array. Then, a peeling speed of ≥20cm / s is used to separate the PBS stamp adhered to the Micro-LED array from the original substrate to obtain a PBS stamp with the Micro-LED array attached. The PBS stamp with the Micro-LED array attached is then laid flat on the target substrate. After sufficient contact, the Micro-LED array is bonded to the target substrate. Finally, a peeling speed of 5-10cm / s is used to separate the PBS stamp from the Micro-LED array.

2. The method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 1, characterized in that: The Young's modulus of the PBS stamp is 0.01~3 MPa.

3. A method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 1 or 2, characterized in that: The preparation process of the PBS stamp is as follows: boric acid is dissolved in methanol to obtain a boric acid solution, then hydroxyl-terminated polydimethylsiloxane is added to the boric acid solution to obtain a mixture, reacted, and the solvent is removed to obtain the stamp.

4. The method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 3, characterized in that: The molecular weight of the hydroxyl-terminated polydimethylsiloxane is 500 to 50,000; the mass ratio of boric acid to methanol is 1:30 to 50. The mass ratio of boric acid to hydroxyl-terminated polydimethylsiloxane is 1:5-10; The reaction temperature is 50-80℃, and the reaction time is 2-4 hours.

5. A method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 1 or 2, characterized in that: The original substrate is a wafer silicon substrate. The wafer silicon substrate and the Micro-LED array are first weakened to obtain a Micro-LED array with a weakened structure. In the weakened structure Micro-LED array, the contact area between the silicon pillar and the Micro-LED array is 1 to 5% of the total bottom area of ​​the Micro-LED array.

6. The method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 5, characterized in that: The weakening process is as follows: first, ICP etching is used to obtain a silicon pillar-supported Micro-LED array, and then an alkaline solution is used to etch the silicon pillar side to form a weakened structure Micro-LED. The alkaline solution is a KOH solution, and the mass fraction of KOH in the KOH solution is 30-45%. The corrosion temperature is 40-60℃, and the corrosion time is 6-8 minutes.

7. A method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 1 or 2, characterized in that: The PBS stamp is laid flat on the surface of the Micro-LED array on the original substrate, and then a pressure of 0.5~1N is applied for 1~3 minutes to ensure that the PBS stamp conformally fits to each Micro-LED pixel in the Micro-LED array.

8. A method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 1 or 2, characterized in that: Clamp the PBS stamp with wide tweezers and separate the PBS stamp attached to the Micro-LED array from the original substrate at a peeling speed of 20~25cm / s.

9. A method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 1 or 2, characterized in that: The target substrate is a PET flexible substrate, and a layer of mist adhesive is first sprayed onto the PET flexible substrate using 3M 75# spray adhesive.

10. A method for transferring Micro-LEDs based on chemical dynamic bonding stamps according to claim 1 or 2, characterized in that: The method of transferring Micro-LEDs using a stamp transfers Micro-LED pixels with a size ≥5µm and an array density ≤2000 PPI.

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