Micro light emitting diode chip transfer device and transfer method thereof

Abstract

The application provides a micro light emitting diode chip transfer device and a transfer method thereof, which comprises a first substrate and a second substrate; the first substrate is driven by a driving electrode to drive a transfer solution containing a micro light emitting diode chip to install the micro light emitting diode chip on the first substrate; the second substrate is provided with a plurality of welding sites, a welding part is arranged in the welding site, and the first substrate and the second substrate are in contact with each other so that the welding part is in contact with the micro light emitting diode chip and reacts to adsorb, so that when the first substrate and the second substrate are separated, the micro light emitting diode chip is transferred from the first substrate to the second substrate, and the transfer yield of the micro light emitting diode chip is improved.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, and in particular to a micro light-emitting diode chip transfer device and transfer method thereof. Background Technology

[0002] Light-emitting diode (LED) display panels are widely used display devices, offering advantages such as high brightness, wide dynamic range, long lifespan, and stability and reliability. Micro-light-emitting diodes (MLEDs) are traditional LEDs that are arrayed and miniaturized, achieving higher resolution, brightness, and contrast than traditional LEDs.

[0003] However, mass transfer of micro-LED chips is a crucial step in the fabrication of miniature LED display panels. Mass transfer refers to the precise transfer of millions or even tens of millions of micro-LED chips from the growth substrate to the driving backplane. However, due to the large number of micro-LED chips to be transferred and the high difficulty of the transfer, some micro-LED chips are easily damaged during the transfer process, thus affecting the transfer yield.

[0004] Therefore, how to transfer miniature LED chips to improve their transfer yield is an urgent problem to be solved. Summary of the Invention

[0005] In view of this, the purpose of this application is to provide a micro light-emitting diode chip transfer device for transferring micro light-emitting diodes.

[0006] To achieve the above objectives, this application provides a micro LED chip transfer device, comprising:

[0007] A first substrate includes a liquid storage area and a transfer area. The liquid storage area is used to store a transfer solution containing a micro LED chip. The transfer area has multiple independent mounting positions for mounting the micro LED chip. A driving electrode is provided on the surface of the first substrate. The driving electrode is used to drive the transfer solution from the liquid storage area to the transfer area after being energized, thereby mounting the micro LED chip in the transfer solution to the mounting position.

[0008] The second substrate has multiple independent soldering positions, each soldering position having a soldering part. When the first substrate and the second substrate are in contact, the soldering part reacts with and adsorbs the micro LED chip, thereby transferring the micro LED chip from the mounting position to the soldering position.

[0009] In one embodiment, the transfer region is coated with a hydrophobic material to form a hydrophobic region on the surface of the transfer region.

[0010] In one embodiment, the transfer region is modified to form the mounting position, the mounting position having an adsorption force on the micro LED chip, and the adsorption force of the mounting position on the micro LED chip is less than the adsorption force of the solder portion on the micro LED chip.

[0011] In one embodiment, the area of ​​the mounting position is less than or equal to the mounting area of ​​the micro LED chip on the mounting position.

[0012] In one embodiment, the liquid storage area is disposed on one side of the transfer area, or on both sides of the transfer area, or surrounding the transfer area.

[0013] In one embodiment, the second substrate is coated with molten solder to form the welded portion.

[0014] In one embodiment, the plurality of mounting positions are arranged in an array within the transfer area;

[0015] And / or, multiple of the welding sites are arranged in an array on the second substrate.

[0016] In one embodiment, the liquid storage area includes a first liquid storage area, a second liquid storage area, and a third liquid storage area. The first liquid storage area is used to store a transfer solution containing a red pixel micro-light-emitting diode chip, the second liquid storage area is used to store a transfer solution containing a green pixel micro-light-emitting diode chip, and the third liquid storage area is used to store a transfer solution containing a blue pixel micro-light-emitting diode chip.

[0017] In one embodiment, it further includes an upper mold and a lower mold; the first substrate is disposed on the upper surface of the lower mold, and the second substrate is disposed on the lower surface of the upper mold; the upper mold is movable up and down, the upper mold moves downward until the second substrate and the first substrate are in direct contact, thereby causing the welding part to react with and be attracted to the micro light-emitting diode chip, and the upper mold moves upward to separate the second substrate from the first substrate, thereby transferring the micro light-emitting diode chip located on the first substrate to the second substrate.

[0018] Based on the same inventive concept, this application also discloses a method for transferring a micro light-emitting diode, applied to the micro light-emitting diode chip transfer device described in any one of the above claims, comprising:

[0019] A transfer solution containing a micro light-emitting diode chip is placed in the reservoir area;

[0020] The driving electrode is energized to drive the transfer solution to transfer into the transfer region;

[0021] The first substrate and the second substrate are brought into contact and separated so as to transfer the micro LED chip in the transfer solution from the first substrate to the second substrate.

[0022] Compared with the prior art, the micro LED chip transfer device provided in this application drives the solution containing the micro LED chip to the transfer area through electrodes, thereby mounting the micro LED chip to the mounting position, and contacts the first substrate and the second substrate to react and bond the solder part with the micro LED chip, thereby transferring the micro LED chip to the second substrate, thereby improving the transfer yield of the micro LED chip. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A schematic diagram of the first substrate of a micro light-emitting diode chip transfer device provided in an embodiment of this application;

[0025] Figure 2 for Figure 1 The diagram shown is a schematic of a miniature light-emitting diode chip mounted on the first substrate.

[0026] Figure 3 A schematic diagram of the second substrate of a micro light-emitting diode chip transfer device provided in another embodiment of this application;

[0027] Figure 4 A schematic diagram of the first substrate before mounting the micro light-emitting diode chip, provided in another embodiment of this application;

[0028] Figure 5 A schematic diagram illustrating the transfer of a miniature light-emitting diode chip from a first substrate to a second substrate, provided as another embodiment of this application;

[0029] Figure 6A flowchart of a method for transferring a miniature light-emitting diode chip according to another embodiment of this application.

[0030] Marker explanation:

[0031] 10. First substrate; 11. Transfer region; 111. Mounting position; 12. Liquid storage region; 13. Driving electrode;

[0032] 20. Second substrate; 21. Soldering position;

[0033] 200. Miniature LED chip. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0035] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0036] Micro LED (Micro Light Emitting Diode) is an emerging display technology that miniaturizes traditional light-emitting diodes (LEDs). It integrates micron-sized LED chips into an array on a substrate, controlling the emission state of each chip via a driving circuit to achieve image display. Each micro LED chip can be independently controlled to emit light, enabling the precise presentation of images with high resolution, high contrast, and high brightness.

[0037] A miniature LED screen comprises LED chips, a driving backplane, and encapsulation materials. The LED chip, or miniature LED chip, is the core component of the screen. It is typically made of semiconductor materials such as gallium nitride (GaN), has an extremely small size, and emits different colors of light when excited by an electrical signal. The driving backplane controls and drives the operation of the miniature LED chips. It is usually composed of a thin-film transistor (TFT) array, which precisely controls the current, voltage, and emission time of each miniature LED chip to achieve accurate image display. The encapsulation material protects the miniature LED chips and the driving backplane from damage caused by external environmental factors and also optimizes the optics, improving the light extraction efficiency of the miniature LED chips.

[0038] Screens made of miniature light-emitting diodes (LEDs) can achieve very high brightness, displaying images clearly even in bright light. At the same time, because each pixel made of a miniature LED can be controlled independently, true black can be achieved, resulting in extremely high contrast.

[0039] Miniature light-emitting diodes (LEDs) can achieve high-density pixel arrangement on screens, thus providing ultra-high resolution display effects; in addition, miniature LEDs also have extremely high response speed, support high refresh rates, and are suitable for displaying dynamic images.

[0040] Miniature LEDs have a long lifespan and can operate for a long time under normal conditions. Furthermore, miniature LEDs consume almost no energy when displaying black, resulting in lower power consumption compared to traditional display technologies.

[0041] Miniature light-emitting diodes (LEDs) can emit purer red, green, and blue primary colors of light, have a wider color gamut, and can accurately reproduce various colors, presenting more realistic and vivid images.

[0042] The manufacturing of miniature light-emitting diode screens includes steps such as epitaxial wafer growth, chip fabrication, chip transfer, packaging, testing, sorting, and assembly.

[0043] Chip transfer, also known as mass transfer, is a key process in the manufacturing of miniature light-emitting diodes (LEDs). It refers to the process of precisely transferring a large number (usually millions or even tens of millions) of miniature LED chips from their growth substrate to a driver backplane.

[0044] These micro LED chips are tiny, typically at the micrometer level. To quickly and accurately transfer such a large number of micro LED chips to a designated location, each micro LED chip must be precisely placed on the corresponding electrode position on the driver backplane. The positional accuracy requirements for the micro LED chips are typically at the micrometer or even sub-micrometer level to ensure good electrical connection between the micro LED chips and the electrodes and consistent display effects.

[0045] Meanwhile, in order to meet the needs of large-scale production, a large number of micro LED chips need to be transferred in a short period of time. This requires the micro LED transfer equipment to have high-speed operation capabilities, and at the same time, it is necessary to ensure the quality and stability of the micro LED chips during the transfer process, and to avoid problems such as damage, displacement or poor electrical connection of the micro LED chips as much as possible, so as to ensure a high transfer yield. This is because any damage, displacement or poor electrical connection of any micro LED chip during the transfer process may directly affect the display quality of the entire micro LED display panel.

[0046] Based on this, the purpose of this application is to provide a micro light-emitting diode chip transfer device to improve the transfer yield of micro light-emitting diode chips.

[0047] Please refer to Figures 1 to 5 As shown, a micro light-emitting diode chip transfer device provided in an embodiment of this application includes: a first substrate 10 and a second substrate 20.

[0048] The first substrate 10 includes a liquid storage region 12 and a transfer region 11. The liquid storage region 12 is used to store a transfer solution containing a micro LED chip. The transfer region 11 has a plurality of independent mounting positions 111 for mounting the micro LED chip 200. A driving electrode 13 is provided on the surface of the first substrate 10. The driving electrode 13 is used to drive the transfer solution from the liquid storage region 12 to the transfer region 11 after being energized, thereby mounting the micro LED chip in the transfer solution onto the mounting position 111.

[0049] The second substrate 20 is provided with a plurality of independent soldering positions 21. Each soldering position 21 is provided with a soldering part, which is used to react with the micro light-emitting diode chip 200 and adsorb the micro light-emitting diode chip 200, thereby transferring the micro light-emitting diode chip 200 from the mounting position 111 to the soldering position 21.

[0050] The micro LED chip transfer device provided in this application sets up a first substrate 10, on which a driving electrode 13 is provided. When the driving electrode 13 is energized, it drives the transfer solution containing the micro LED chip 200 to be transferred from the storage area 12 to the mounting position 111 on the transfer area 11. Thus, all the micro LED chips 200 in the transfer solution can be mounted on the mounting position 111 in one go, thereby improving the transfer efficiency of the micro LED chip 200 and reducing the production cost.

[0051] Meanwhile, by precisely controlling the electric field strength, direction and duration of the driving electrode 13, the transfer solution can be precisely manipulated to flow to the mounting position 111 on the transfer region 11, thereby achieving high-precision positioning of the micro LED chip 200 during transfer and thus accurately arranging the micro LED chip 200.

[0052] The micro LED chip transfer device provided in this application provides a second substrate 20 with multiple soldering positions 21. By contacting the first substrate 10 with the second substrate 20, the soldering portion on the second substrate 20 reacts and bonds with the micro LED chip 200 located at the mounting position 111 on the first substrate 10. When the first substrate 10 and the second substrate 20 are separated, the micro LED chip 200 detaches from the mounting position 111 and is transferred to the soldering position 21, thereby realizing the transfer of the micro LED chip 200 from the first substrate 10 to the second substrate 20.

[0053] In one embodiment, the transfer region 11 is modified to form a mounting position 111, which has an adsorption force on the micro LED chip 200, and the adsorption force of the mounting position 111 on the micro LED chip 200 is less than the adsorption force of the solder joint on the micro LED chip 200.

[0054] The micro LED chip transfer device provided in this application modifies the transfer region 11 to form a mounting position 111. The modified mounting position 111 can adsorb the micro LED chip 200. When the transfer solution flows through the transfer region 11 via the driving electrode 13, the mounting position 111 can adsorb the micro LED chip 200 in the transfer solution, thereby fixing the micro LED chip 200 onto the mounting position 111. Furthermore, the adsorption force of the mounting position 111 on the micro LED chip 200 is less than the adsorption force of the soldering part on the micro LED chip 200. This allows the micro LED chip 200 to be transferred from the first substrate 10 to the second substrate 20 after the first substrate 10 contacts and separates from the second substrate 20, thus realizing the transfer of the micro LED chip 200.

[0055] Specifically, in one embodiment, the transfer region 11 can be modified by placing the first substrate 10 in a reaction chamber containing a specific gas, and depositing a thin film such as silicon nitride or silicon oxide (not shown) on the surface of the transfer region 11 of the first substrate 10 using a chemical reaction. These films can provide a flat and smooth surface, which is beneficial for the adhesion of the micro-LED chip 200. At the same time, these films can also isolate and protect the first substrate 10, preventing external impurities from affecting the micro-LED chip 200 and the first substrate 10. In addition, the surface properties of the deposited film can be controlled by adjusting the reaction conditions to give it an appropriate surface energy, thereby enhancing the interaction force between the micro-LED chip 200 and the mounting position 111, and making the micro-LED chip 200 firmly attached to the mounting position 111.

[0056] Optionally, in one embodiment, high-energy particles in plasma can be used to bombard and modify the surface of the transfer region 11 of the first substrate 10, thereby cleaning the surface of the transfer region 11, removing impurities and contaminants, and improving the purity of the transfer region 11 surface. Simultaneously, bombarding and modifying the transfer region 11 with high-energy particles can also change the chemical properties and microstructure of the transfer region 11 surface, increasing the surface roughness or introducing some active groups, thereby forming mounting sites 111. Increasing the roughness can improve the mechanical interlocking between the micro-LED chip 200 and the mounting site 111, while the introduction of active groups can chemically react with the substances on the surface of the micro-LED chip 200 to form chemical bonds, thereby improving the adhesion of the micro-LED chip 200 to the mounting site 111.

[0057] Alternatively, in one embodiment, a specific pattern can be created in the transfer area 11 of the first substrate 10 using photolithography, and then the unwanted parts can be removed by etching to form a mounting position 111 with a specific shape and structure, so that the micro light-emitting diode chip 200 can be accurately placed in the mounting position 111 to achieve high-precision positioning and tight attachment.

[0058] Alternatively, in another embodiment, the surface of the transfer region 11 of the first substrate 10 can be activated by using a chemical solution or physical method to make the surface of the transfer region 11 more active, thereby forming mounting sites 111. For example, the surface of the transfer region 11 can be immersed in an acid or alkali solution to remove the oxide layer or other impurities on the surface of the transfer region 11 and form some tiny uneven structures or active sites on the surface of the transfer region 11, which are the mounting sites 111; or physical methods such as ultraviolet irradiation or electron beam irradiation can be used to excite the molecules or atoms on the surface of the transfer region 11, making them in an activated state, forming mounting sites 111, and improving the reactivity and adhesion with the surface of the micro light-emitting diode chip 200.

[0059] Although this application exemplifies various methods of modifying the surface of the first substrate 10 to form the mounting position 111, this application does not limit the methods of modifying the surface of the first substrate 10 to form the mounting position 111. Other types of methods of modifying the surface of the first substrate 10 to form the mounting position 111 are also within the scope of protection of this application.

[0060] Preferably, the area of ​​the mounting position 111 is less than or equal to the mounting area of ​​the micro LED chip 200 on the mounting position 111. This application limits the area of ​​the mounting position 111 to be less than the mounting area of ​​the micro LED chip 200 on the mounting position 111, ensuring that only one micro LED chip 200 is mounted on each mounting position 111. This provides a precise mounting position for the micro LED chip 200, preventing multiple micro LED chips 200 from crowding onto one mounting position 111 and causing damage to each other. It also ensures that the micro LED chip 200 is accurately mounted on the mounting position 111 during the mounting process, reducing deviations during installation. This facilitates high-density, high-precision transfer of the micro LED chips 200 in the transfer solution to the transfer area 11.

[0061] Furthermore, when the area of ​​mounting position 111 is less than or equal to the mounting area of ​​the micro LED chip 200 on mounting position 111, the contact between the micro LED chip 200 and mounting position 111 is tighter, and the micro LED chip 200 can better remain in place when subjected to external impact or vibration, reducing the risk of the micro LED chip 200 falling off or shifting.

[0062] Finally, when fabricating mounting positions 111 on the first substrate 10, a smaller mounting position 111 area means that more mounting positions 111 can be fabricated on the first substrate 10, thereby improving the utilization rate of the first substrate 10, reducing waste, and thus reducing production costs.

[0063] Optionally, the micro LED chip transfer device provided in this application may have more than one million mounting positions 111 on the first substrate 10. These mounting positions 111 are arranged in an array within the transfer area 11, so that when the driving electrode 13 drives the transfer solution to move to the transfer area 11, the transfer solution can simultaneously transport multiple micro LED chips 200 to the corresponding mounting positions 111, eliminating the need to install each micro LED chip 200 individually. This significantly shortens the transfer time of the micro LED chip 200, improves overall production efficiency, and can meet the market's demand for large-volume micro LED chips 200.

[0064] Meanwhile, the mounting positions 111 are arranged in an array, exhibiting a high degree of regularity and repeatability, which perfectly matches the working characteristics of automated production equipment. Whether it is driving the transfer solution to install the micro LED chip 200 during the transfer process, or subsequently docking and transferring the first substrate 10 and the second substrate 20, the automated equipment can accurately execute each operation step according to the preset array coordinates and program, reducing the difficulty of equipment programming and debugging, minimizing human intervention in the production process, and improving the stability and reliability of production.

[0065] Because the mounting positions 111 are arranged in an array, the position and spacing of each mounting position 111 are precisely set. During the process of transferring the micro LED chip 200 to the mounting position 111, the electric field generated by the driving electrode 13 can act more uniformly on the transfer solution, so that the micro LED chip 200 in the transfer solution can accurately reach the corresponding mounting position 111 according to the predetermined path and position.

[0066] Meanwhile, the array arrangement of mounting positions 111 facilitates high-precision positioning and calibration during the transfer process, ensuring that each micro LED chip 200 can be installed on the designated mounting position 111. This effectively avoids inconsistent performance of the micro LED chip 200 due to installation position deviations, and improves the transfer yield of the micro LED chip 200.

[0067] Optionally, in one embodiment, the micro LED chip transfer device provided in this application may only have one liquid storage area 12, which is located on one side of the transfer area 11.

[0068] In another embodiment, multiple liquid storage areas 12 may be provided, and the multiple liquid storage areas 12 may be provided on both sides of the transfer area 11 or surrounding the transfer area 11. This application does not limit this.

[0069] Furthermore, the liquid storage area 12 includes a first liquid storage area, a second liquid storage area, and a third liquid storage area (not shown). The first liquid storage area is used to store a transfer solution containing a red pixel micro-light-emitting diode chip, the second liquid storage area is used to store a transfer solution containing a green pixel micro-light-emitting diode chip, and the third liquid storage area is used to store a transfer solution containing a blue pixel micro-light-emitting diode chip.

[0070] The micro LED chip transfer device provided in this application sets up a first liquid storage area, a second liquid storage area, and a third liquid storage area. The first liquid storage area, the second liquid storage area, and the third liquid storage area respectively store a transfer solution containing a red pixel micro LED chip, a transfer solution containing a green pixel micro LED chip, and a transfer solution containing a blue pixel micro LED chip. This prevents the transfer solutions containing different types of micro LED chips 200 from mixing with each other, which would cause color mixing, thereby achieving high-precision installation and positioning.

[0071] Meanwhile, since different types of micro LED chips 200 have different material properties, corresponding liquid storage areas are set up respectively, so that corresponding transfer strategies can be set for different types of micro LED chips 200, thereby improving the transfer efficiency and transfer yield of micro LED chips 200.

[0072] Optionally, in one embodiment, the storage area 12 has a groove-shaped structure (not shown), and the junction of the storage area 12 and the transfer area 11 is sealed to prevent the transfer solution from leaking into the transfer area 11 when the transfer solution in the storage area 12 is not transferred.

[0073] Optionally, in one embodiment, the driving electrodes 13 have an interlaced comb-like structure, enabling them to generate a uniform and controllable electric field when energized. When the driving electrodes 13 are powered on, the electric field formed between them induces electroosmotic flow in the transfer solution within the storage region 12, thereby propelling the transfer solution along a predetermined path on the surface of the first substrate 10 from the storage region 12 to the first transfer region 11. During the process of the transfer solution being driven by the driving electrodes 13, the micro-LED chip 200 is transported to the first transfer region 11 along with the transfer solution, and is mounted on the mounting position 111 by the adsorption force of the mounting position 111, achieving precise transfer of the micro-LED chip 200.

[0074] Optionally, in one embodiment, the driving electrode 13 may be made of a metallic material such as copper or gold, which has high conductivity, thereby achieving higher conductivity, reducing energy waste, and saving costs.

[0075] In one embodiment, the micro LED chip transfer device provided in this application forms a hydrophobic region (not shown) on the surface of the transfer region 11 by coating the transfer region 11 with a hydrophobic material.

[0076] The presence of the hydrophobic region alters the wettability of the surface of the first substrate 10, increasing the contact angle of the transfer solution on the surface of the first substrate 10. When the driving electrode 13 is energized to generate an electric field and drive the transfer solution, due to the repulsive effect of the hydrophobic region on the transfer solution, the transfer solution tends to move along the pre-set path from the storage region 12 to the first transfer region 11, rather than randomly spreading to other areas of the first substrate 10. This ensures that the transfer solution can accurately reach the mounting position 111 of the first transfer region 11, avoiding deviations in the mounting position of the micro LED chip 200 due to diffusion of the transfer solution, thereby improving the transfer yield of the micro LED chip 200.

[0077] Meanwhile, the low surface energy of the hydrophobic region makes it difficult for residual transfer solution to adhere to the surface of the first substrate 10. After the mounting steps of the micro LED chip 200 are completed, the remaining transfer solution can be more easily removed due to the hydrophobic effect, reducing the amount of residual transfer solution on the surface of the first substrate 10. This avoids the possible impact of residual transfer solution on subsequent processes and can also effectively prevent cross-contamination between different batches of transfer solutions, ensuring the independence and cleanliness of each micro LED chip 200 transfer process, thereby improving the transfer yield of the micro LED chip 200.

[0078] Finally, due to the characteristics of the hydrophobic region, impurities and residual solutions adhering to the first substrate 10 are more easily cleaned away, thereby extending the service life of the first substrate 10 and reducing production costs.

[0079] Optionally, in one embodiment, molten solder is coated on the second substrate 20 to form a welded portion. The second substrate 20 serves as the final carrier for the micro-LED chip 200, and the molten solder coating thereon forms the welded portion. The welded portion can contact and react with the micro-LED chip 200, thereby adsorbing the micro-LED chip 200.

[0080] In one embodiment, the solder can be a tin-silver-copper (SAC) alloy solder with a low melting point. This type of solder not only has good electrical conductivity and mechanical strength, but also melts at a relatively low temperature, thereby avoiding damage to the surface of the second substrate 20 caused by high temperature.

[0081] In another embodiment, the solder may also be a metal solder containing indium (In), which has excellent ductility and low-temperature welding characteristics, thus reducing damage to the second substrate 20 during solder coating.

[0082] Optionally, solder can be applied to the second substrate 20 using high-precision printing or spraying techniques.

[0083] In one embodiment, molten solder can be evenly applied to a screen using screen printing technology, and the molten solder can be precisely deposited into the soldering position 21 of the second substrate 20 by the extrusion of a scraper through the perforated portion of the screen.

[0084] In another embodiment, a jet dispensing technique can be used to precisely spray molten solder in the form of tiny droplets onto the soldering position 21 of the second substrate 20 using air pressure or piezoelectric drive, ensuring the consistency and accuracy of the solder amount.

[0085] Optionally, in one embodiment, the micro LED chip transfer device provided in this application has multiple soldering positions 21 arranged in an array, so that the soldering positions 21 can form a strict coordinate mapping with the mounting positions 111 on the first substrate 10. When the first substrate 10 is released from and attached to the second substrate 20, the micro LED chip 200 on the mounting position 111 falls into the corresponding soldering position 21 with high precision and contacts and reacts with the soldering part in the soldering position 21, thereby adsorbing the micro LED chip 200 onto the soldering position 21, thereby avoiding misalignment between the micro LED chip 200 and the soldering part due to positional deviation, and improving the transfer yield of the micro LED chip 200.

[0086] Since the second substrate 20 is the target substrate for transfer, the second substrate 20 will be packaged and other processes to manufacture a micro light-emitting diode screen. Therefore, the soldering positions 21 are arranged in an array, so that the micro light-emitting diode chips 200 can naturally form independent pixel modules after transfer, thereby improving the arrangement accuracy of the micro light-emitting diode chips 200 and presenting a higher resolution image.

[0087] Meanwhile, the welding positions 21 are arranged in an array, which facilitates the batch welding process of the welding positions 21 to form welding positions 21, thereby improving the manufacturing efficiency of the welding positions 21 and ultimately improving production efficiency.

[0088] The number of soldering positions 21 in the miniature light-emitting diode chip transfer device provided in this application can be the same as the number of mounting positions 111.

[0089] In one embodiment, the number of soldering positions 21 is less than the number of mounting positions 111, and the area of ​​the first substrate 10 is greater than the area of ​​the second substrate 20. Therefore, when transferring the micro LED chip 200 on the first substrate 10 to the second substrate 20, the efficiency of transferring the micro LED chip 200 can be improved by having multiple second substrates 20 in direct contact with the first substrate 10 at one time.

[0090] In another embodiment, the number of soldering positions 21 is greater than the number of mounting positions 111, and the area of ​​the first substrate 10 is smaller than the area of ​​the second substrate 20. Therefore, when transferring the micro LED chip 200 on the first substrate 10 to the second substrate 20, the efficiency of transferring the micro LED chip 200 can be improved by having multiple first substrates 10 and second substrate 20 in direct contact at one time.

[0091] Optionally, in one embodiment, the micro LED chip transfer device provided in this application further includes an upper mold (not shown) and a lower mold (not shown). A first substrate 10 is disposed on the upper surface of the lower mold, and a second substrate 20 is disposed on the lower surface of the upper mold. The upper mold can move up and down. When the upper mold moves downward, the second substrate 20 and the first substrate 10 are in direct contact, thereby allowing the solder joint to react with and adhere to the micro LED chip 200. When the upper mold moves upward, it separates the second substrate 20 from the first substrate 10, thereby transferring the micro LED chip 200 located on the first substrate 10 to the second substrate 20.

[0092] The micro LED chip transfer device provided in this application sets up an upper mold and a lower mold. The lower mold is used to place the first substrate 10, and the second substrate 20 is disposed on the lower surface of the upper mold. The contact and separation of the first substrate 10 and the second substrate 20 are realized by the up and down movement of the upper mold, making the whole process more stable and preventing problems such as displacement of the micro LED chip 200 during the transfer process, thereby improving the transfer yield of the micro LED chip 200.

[0093] Optionally, the upper mold provided in this application can be a suction cup, and the lower mold can be a placement table or other equipment; this application does not impose any restrictions on this.

[0094] Based on the same inventive concept, please refer to Figure 6 As shown, another embodiment of this application also discloses a method for transferring a micro LED chip, applied to the micro LED chip transfer apparatus in the above embodiment, which includes the following steps:

[0095] S10. Place the transfer solution containing the micro light-emitting diode chip 200 in the storage area 12;

[0096] S20. Power is applied to the driving electrode 13 to drive the transfer solution to transfer into the transfer region 11;

[0097] S30. The first substrate 10 and the second substrate 20 are brought into contact and separated so as to transfer the micro light-emitting diode chip 200 in the transfer solution from the first substrate 10 to the second substrate 20.

[0098] The micro-LED chip transfer method provided in this application transfers the micro-LED chip 200 to the second substrate 20 by driving the transfer solution with driving electrodes and inducing peeling by utilizing the surface energy of the welding part. This method can effectively improve the transfer yield of the micro-LED chip 200. Furthermore, this method is compatible with standardized photolithography processes and automated production lines, providing an efficient and reliable technical path for the large-scale production of the micro-LED chip 200.

[0099] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0100] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0101] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A micro light emitting diode chip transfer apparatus, characterized by, include: A first substrate includes a liquid storage area and a transfer area. The liquid storage area is used to store a transfer solution containing a micro LED chip. The transfer area has multiple independent mounting positions for mounting the micro LED chip. A driving electrode is provided on the surface of the first substrate. The driving electrode is used to drive the transfer solution from the liquid storage area to the transfer area after being energized, thereby mounting the micro LED chip in the transfer solution to the mounting position. The second substrate has multiple independent soldering positions, each soldering position having a soldering part. When the first substrate and the second substrate are in contact, the soldering part reacts with and adsorbs the micro LED chip, thereby transferring the micro LED chip from the mounting position to the soldering position.

2. The micro light emitting diode chip transfer apparatus of claim 1, wherein, The transfer region is coated with a hydrophobic material to form a hydrophobic region on the surface of the transfer region.

3. The micro light emitting diode chip transfer apparatus of claim 1, wherein, The transfer area is modified to form the mounting position, which has an adsorption force on the micro LED chip, and the adsorption force of the mounting position on the micro LED chip is less than the adsorption force of the solder joint on the micro LED chip.

4. The micro light emitting diode chip transfer apparatus of claim 3, wherein, The area of ​​the mounting position is less than or equal to the mounting area of ​​the micro LED chip on the mounting position.

5. The micro light emitting diode chip transfer apparatus of claim 1, wherein, The liquid storage area is located on one side of the transfer area, or on both sides of the transfer area, or surrounding the transfer area.

6. The micro light emitting diode chip transfer apparatus of claim 1, wherein, The second substrate is coated with molten solder to form the welded portion.

7. The micro light emitting diode chip transfer apparatus of claim 1, wherein, Multiple mounting positions are arranged in an array within the transfer area; And / or, multiple of the welding sites are arranged in an array on the second substrate.

8. The micro light emitting diode chip transfer apparatus of claim 1, wherein, The liquid storage area includes a first liquid storage area, a second liquid storage area, and a third liquid storage area. The first liquid storage area is used to store a transfer solution containing a red pixel micro light-emitting diode chip, the second liquid storage area is used to store a transfer solution containing a green pixel micro light-emitting diode chip, and the third liquid storage area is used to store a transfer solution containing a blue pixel micro light-emitting diode chip.

9. The micro light emitting diode chip transfer apparatus of any one of claims 1-8, wherein, It also includes an upper mold and a lower mold; the first substrate is disposed on the upper surface of the lower mold, and the second substrate is disposed on the lower surface of the upper mold; the upper mold can move up and down, the upper mold moves down until the second substrate and the first substrate are in direct contact, so that the welding part reacts with and is adsorbed by the micro light-emitting diode chip, and the upper mold moves up to separate the second substrate from the first substrate, thereby transferring the micro light-emitting diode chip located on the first substrate to the second substrate.

10. A micro LED chip transfer method applied to the micro LED chip transfer device according to any one of claims 1-9, characterized in that, include: A transfer solution containing a micro light-emitting diode chip is placed in the reservoir area; The driving electrode is energized to drive the transfer solution to transfer into the transfer region; The first substrate and the second substrate are brought into contact and separated so as to transfer the micro LED chip in the transfer solution from the first substrate to the second substrate.

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