Multi-needle-head mechanical thorn crystal type Mini-LED mass transfer system and use method of multi-needle-head mechanical thorn crystal type Mini-LED mass transfer system

Abstract

The invention discloses a multi-needle mechanical crystal-stabbing type Mini-LED mass transfer system and a use method, the system comprises a substrate assembly line, a planar motion platform and a multi-needle crystal-stabbing device, the multi-needle crystal-stabbing device comprises a crystal-stabbing head assembly and a three-axis motion gantry, the crystal-stabbing head assembly comprises a bottom plate and a plurality of sub crystal-stabbing heads, and the sub crystal-stabbing heads are arranged on the bottom plate. The bottom plate is provided with a needle outlet hole, and the plurality of sub-stabbing crystal heads are distributed around the periphery of the needle outlet hole; the sub-stabbing crystal head comprises a shell, a motor and a tungsten needle clamp, the shell is provided with a guide rail, the tungsten needle clamp is arranged on the shell in a guiding and sliding mode along the guide rail, and the tungsten needle is switched between a first position state and a second position state through movement of the tungsten needle clamp. In addition, the invention further provides a using method using the system, and the multi-needle-head mechanical crystal-stabbing type Mini-LED mass transfer system and method solve the problems that at present, the transfer efficiency is low, the needle head density is limited by the thickness of a needle rod, and the packaging precision is limited.

Description

Technical Field

[0001] The present invention relates to the field of LED chip transfer and packaging technology, and in particular to a multi-needle mechanical crystal pricking type Mini-LED mass transfer system and a use method. Background Art

[0002] Currently, with the advancement of technology, a paradigm shift has occurred in the display field. Displays require high resolution, high stability and small size to meet the requirements of applications such as ultra-high-definition displays, flexible or wearable displays, augmented reality and virtual reality. For these applications, traditional display technologies such as liquid crystal displays (LCDs) or organic light-emitting diodes (OLEDs) are not suitable. Compared with traditional LEDs, Mini / Micro LEDs have a compact structure, high light extraction efficiency, good current diffusion, low self-heating effect, short response time, low power consumption and high visible light communication performance. Especially in terms of optoelectronics, Mini / Micro LEDs have limited wavelength shift, high brightness and high contrast. Most importantly, thanks to the inorganic characteristics of Mini / Micro LEDs, they have an ultra-long service life of more than 10 years and excellent environmental tolerance.

[0003] However, making a Mini / Micro LED display panel requires transferring tens of millions of chips on a substrate, and the traditional chip transfer technology is based on the pick and place method, that is, the mobile arm picks up a single chip or a chip array and repositions them to the target substrate. However, as the chip size is reduced to the micron level, this method not only has the problem of difficult chip picking, but also has low efficiency. Therefore, mass transfer technology came into being. Among them, mechanical thorn crystal technology has the advantages of low cost and high efficiency. This method uses a needle to directly transfer the chip on the blue film to the substrate, but this technology requires the needle, chip, and substrate to be aligned for each chip transferred. The movement of the device needs to be started and stopped frequently, which not only reduces the efficiency of the transfer, but also the vibration generated greatly reduces the accuracy of the packaging. In order to improve efficiency, there will be an array needle design at this stage, but the needle density is restricted by the thickness of the needle rod, and the needle density cannot be increased to adapt to the needs of different spacing. Summary of the invention

[0004] In view of the above-mentioned defects, the purpose of the present invention is to propose a multi-needle mechanical pricking crystal Mini-LED mass transfer system and use method to solve the current problems of low transfer efficiency, needle density being restricted by the thickness of the needle rod, and limited packaging accuracy.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A multi-needle mechanical crystal pricking type Mini-LED mass transfer system, including a substrate assembly line, a planar motion platform and a multi-needle crystal pricking device;

[0007] A scanning camera is provided on one side of the planar motion platform close to the multi-needle crystal pricking device, and a chip carrier is provided on the planar motion platform, and the chip carrier is used to fix the blue film;

[0008] The multi-needle crystal piercing device includes a crystal piercing head assembly and a three-axis motion gantry, wherein the crystal piercing head assembly is fixed at the output end of the three-axis motion gantry, and the crystal piercing head assembly is driven by the three-axis motion gantry; the crystal piercing head assembly includes a bottom plate and a plurality of sub-crystal piercing heads, wherein the bottom plate is provided with a pin hole, and the plurality of sub-crystal piercing heads are distributed around the periphery of the pin hole; the sub-crystal piercing heads include a shell, a motor and a tungsten needle clamp, wherein the shell is provided with a guide rail, and the tungsten needle clamp is slidably arranged on the shell along the guide rail, and the motor drives the tungsten needle clamp to move along the guide rail, and the tungsten needle clamp is provided with a tungsten needle, and the movement of the tungsten needle clamp enables the tungsten needle to switch between a first position state and a second position state, and when the tungsten needle is in the first position state, the tungsten needle does not pass through the pin hole, and the axis of the tungsten needle is not colinear with the axis of the pin hole, and when the tungsten needle is switched to the second position state, the tungsten needle passes through the pin hole and acts on the blue film on the chip carrier;

[0009] The substrate assembly line is located on the side of the planar motion platform away from the multi-needle crystal piercing device. The substrate assembly line includes a transport track, a limiter and a negative pressure suction cup. The transport track is used to transport the substrate to the desired position. The limiter is located on both sides of the transport track. The negative pressure suction cup is located in the middle of the transport track. The limiter and the negative pressure suction cup are used to fix the substrate.

[0010] Furthermore, the motor is fixedly mounted on the top of the shell, the tungsten needle clamp is passed through the shell, the driving end of the motor is connected to the tungsten needle clamp, the sub-crystal head also includes an elastic member, one end of the elastic member is located below the tungsten needle clamp, and the other end of the elastic member is fixed in the shell, the motor drives the tungsten needle clamp to compress the elastic member downward and move to the second position state, and the elastic member drives the tungsten needle clamp to restore the first position state upward.

[0011] Furthermore, a slider is provided between the elastic member and the tungsten needle clamp, and the slider is slidably connected with the elastic member and the tungsten needle clamp. Two elastic members are provided, and the two elastic members are connected with both ends of the bottom of the slider.

[0012] Preferably, the crystal piercing head assembly also includes a central crystal piercing head, which is located directly above the pinhole. The central crystal piercing head includes a motor and a central tungsten needle. The motor drives the central tungsten needle vertically downward through the pinhole and acts on the blue film on the chip carrier, or drives the central tungsten needle vertically upward to exit the pinhole, and the axis of the central tungsten needle is collinear with the axis of the pinhole.

[0013] Further, the guide rail is an arc segment guide rail, and a plurality of the sub-thorn crystal heads are arranged in an array; the number of the sub-thorn crystal heads is 4, and the 4 sub-thorn crystal heads are distributed in a cross shape, and the center of the cross and the center of the pinhole are located on the same vertical axis; or, the number of the sub-thorn crystal heads is 8, and the 8 sub-thorn crystal heads are evenly surrounded by the central thorn crystal head, and the 8 sub-thorn crystal heads are distributed in a cross shape on the bottom plate, and the center of the cross and the center of the pinhole are located on the same vertical axis.

[0014] Furthermore, the guide rails are through grooves arranged opposite to each other on both sides of the shell, guide rods are arranged on both sides of the tungsten needle clamp, the axes of the two guide rods are located on the same line, and the guide rods are slidably clamped in the guide rails.

[0015] A method for using the multi-needle mechanical pricking Mini-LED mass transfer system comprises the following steps:

[0016] S1. Substrate preparation: Place the substrate to be processed on the transport track. When it is transported to the thorn crystal position, the transport track stops moving, the limiter pops up, and the substrate is accurately fixed at the thorn crystal position. The negative pressure suction cup rises and adheres to the lower surface of the substrate to fix the substrate;

[0017] S2. Chip preparation: fix the blue film on the chip carrier, and the planar motion platform drives the chip carrier to the bottom of the scanning camera. The scanning camera obtains the position of all Mini-LED chips through machine vision and stores the records. After completion, the chip carrier moves to the top of the substrate;

[0018] S3, single-area crystal piercing: the crystal piercing head assembly is driven by the three-axis motion gantry to reach the area to be pierced, and the area to be pierced contains an m×n dot matrix, and the dot matrix corresponds one-to-one with the chip pad of the substrate and the needle exit position of the sub-crystalline head; the first point of the dot matrix is ​​selected, and according to the recorded chip position, the planar motion platform drives the chip corresponding to the point to move to the position of "tungsten needle-chip-chip pad" three points in a straight line, and the first tungsten needle reaches the second position state under the drive of the corresponding motor to complete the crystal piercing movement. When the first tungsten needle completes the crystal piercing movement, the second tungsten needle switches to the second position state under the drive of the corresponding motor, and the first tungsten needle switches to the first position state at this time. When the second tungsten needle completes the crystal piercing movement, the third tungsten needle switches to the second position state under the drive of the corresponding motor, and the second tungsten needle switches to the first position state at this time, and so on, to complete the transfer of all chips in the area to be processed;

[0019] S4, positioning transfer: After completing the crystallization of a single area, the multi-needle crystallization device moves to the next area to be crystallized for alignment. After completing the alignment, step S3 is repeated to perform crystallization transfer until all the Mini-LED chips are crystallized.

[0020] Further, in step S3, the planar motion platform drives the chip carrier to perform two-dimensional motion, thereby driving the chip adhered to the blue film to move to a desired position, and the movement route of the chip carrier is an "S"-shaped line.

[0021] Preferably, the Mini-LED chip is rectangular, the long side dimension of the Mini-LED chip is greater than 50 μm, and the short side dimension of the Mini-LED chip is greater than 25 μm; the spacing between the chip pads is 100-1000 microns.

[0022] Preferably, the vacuum degree of the negative pressure suction cup is less than 100Pa.

[0023] The technical solution provided by the present invention may include the following beneficial effects:

[0024] 1. The mass transfer system of this solution uses multiple sub-pin crystal heads, and the tungsten needles of these sub-pin crystal heads can perform telescopic movements. The movement between the tungsten needles is not affected, so that the needle density is not limited by the thickness of the needle rod, adapts to different spacings, and effectively improves the chip transfer efficiency.

[0025] 2. The system usage method of this solution is to use the movement of a planar motion platform instead of the movement of a multi-needle crystal piercing device during single-area crystal piercing, thereby reducing the vibration of the device and improving the packaging accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0027] Figure 2 It is a schematic structural diagram of a spike crystal head assembly according to an embodiment of the present invention.

[0028] Figure 3 It is a schematic structural diagram of a spike crystal head assembly according to an embodiment of the present invention.

[0029] Figure 4 It is a schematic structural diagram of a spike crystal head assembly according to another embodiment of the present invention.

[0030] Figure 5 It is a schematic structural diagram of the sub-thorn crystal head of the present invention.

[0031] Figure 6 It is a schematic structural diagram of the intermediate sub-thorn crystal head of the present invention.

[0032] Figure 7 It is a schematic structural diagram of an embodiment of the present invention.

[0033] Among them: the crystal head assembly 1, the sub-crystal head 11, the base plate 12, the three-axis motion gantry 13, the shell 111, the motor 112, the elastic part 113, the tungsten needle clamp 114, the tungsten needle 115, the slider 116, the guide rail 1111, the guide rod 1141, the pinhole 121, the scanning camera 21, the chip carrier 22, the blue film 223, the transport track 31, the negative pressure suction cup 32, the substrate 33, the chip pad 341, the central crystal head 14, and the central tungsten needle 141. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0035] In the description of the present invention, it is necessary to understand that the terms "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of the features, and are used to distinguish and describe features, without distinction of order or importance.

[0036] In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] The present invention proposes a multi-needle mechanical thorn crystal type Mini-LED mass transfer system, including a substrate assembly line, a planar motion platform and a multi-needle thorn crystal device; a scanning camera 21 is provided on the side of the planar motion platform close to the multi-needle thorn crystal device, and a chip carrier 22 is provided on the planar motion platform, and the chip carrier 22 is used to fix the blue film 223.

[0039] The multi-needle crystal piercing device includes a crystal piercing head assembly 1 and a three-axis motion gantry 13, wherein the crystal piercing head assembly 1 is fixed at the output end of the three-axis motion gantry 13, and the crystal piercing head assembly 1 is driven by the three-axis motion gantry 13; the crystal piercing head assembly 1 includes a base plate 12 and a plurality of sub-crystal piercing heads 11, wherein the base plate 12 is provided with a needle hole 121, and the plurality of sub-crystal piercing heads 11 are distributed around the periphery of the needle hole 121; the sub-crystal piercing heads 11 include a shell 111, a motor 112 and a tungsten needle clamp 114, wherein the shell 111 is provided with a guide rail 1111, and the tungsten needle clamp 114 is set to slide along the guide rail 1111 The shell 111, the motor 112 drives the tungsten needle clamp 114 to move along the guide rail 1111, the tungsten needle clamp 114 is provided with a tungsten needle 115, the movement of the tungsten needle clamp 114 enables the tungsten needle 115 to switch between a first position state and a second position state, when the tungsten needle 115 is in the first position state, the tungsten needle 115 does not pass through the pin hole 121, and the axis of the tungsten needle 115 is not colinear with the axis of the pin hole 121, when the tungsten needle 115 switches to the second position state, the tungsten needle 115 passes through the pin hole 121 and acts on the blue film 223 on the chip carrier 22.

[0040] The substrate assembly line is located on the side of the planar motion platform away from the multi-needle crystal piercing device, and the substrate assembly line includes a transport track 31, a limiter and a negative pressure suction cup 32. The transport track 31 is used to transport the substrate 33 to the desired position, the limiter is located on both sides of the transport track 31, and the negative pressure suction cup 32 is located in the middle of the transport track 31. The limiter and the negative pressure suction cup 32 are used to fix the substrate 33.

[0041] Specifically, for the efficiency of chip transfer, mass transfer technology came into being. Among them, mechanical crystal pricking technology has the advantages of low cost and high efficiency. This method uses a needle to directly transfer the chip on the blue film to the substrate, but this technology requires the needle, chip and substrate to be aligned for each chip transferred. The movement of the device needs to be started and stopped frequently, which not only reduces the efficiency of the transfer, but also the vibration generated greatly reduces the accuracy of the packaging. In order to improve efficiency, there will be an array needle design at this stage, but the needle density is restricted by the thickness of the needle rod, and the needle density cannot be increased to adapt to the needs of different spacing.

[0042] To this end, this solution proposes a multi-needle mechanical thorn crystal Mini-LED mass transfer system, such as Figures 1 to 3As shown, it includes a substrate assembly line, a planar motion platform and a multi-needle crystal piercing device; the multi-needle crystal piercing device includes a crystal piercing head assembly 1 and a three-axis motion gantry 13, the crystal piercing head assembly 1 is fixed on the three-axis motion gantry 13, the crystal piercing head assembly 1 is driven by the three-axis motion gantry 13, the crystal piercing head assembly 1 includes a base plate 12 and a plurality of sub-crystal piercing heads 11, the base plate 12 is provided with a needle hole 121, and the plurality of sub-crystal piercing heads 11 are distributed around the periphery of the needle hole 121; the sub-crystal piercing head 11 includes a shell 111, a motor 112 and a tungsten needle clamp 114, the The housing 111 is provided with a guide rail 1111, and the tungsten needle clamp 114 is slidably arranged on the housing 111 along the guide rail 1111. The motor 112 drives the tungsten needle clamp 114 to move along the guide rail 1111. The tungsten needle clamp 114 is provided with a tungsten needle 115. The movement of the tungsten needle clamp 114 enables the tungsten needle 115 to switch between a first position state and a second position state. When the tungsten needle 115 is in the first position state, the tungsten needle 115 does not pass through the pin hole 121, and the axis of the tungsten needle 115 is not colinear with the axis of the pin hole 121. , the plurality of tungsten needles 115 do not affect each other. When the tungsten needle 115 is switched to the second position state, the tungsten needle 115 passes through the pinhole 121 and acts on the blue film 223 on the chip carrier 22. The plurality of sub-pin crystal heads 11 are provided with the motor 112. The sub-pin crystal heads 11 are capable of operating independently. When the first position state is switched to the second position state, the plurality of tungsten needles 115 move alternately. The operation of the plurality of tungsten needles 115 effectively improves the transfer efficiency. When the first tungsten needle 115 is in the second position state and works, the second tungsten needle 115 is in the first position state and works. The first tungsten needle 115 switches from the second position state to the first position state. When the first tungsten needle 115 finishes working in the second position state, the first tungsten needle 115 switches from the second position state to the first position state, and the second tungsten needle 115 can immediately be in the second position state to perform work, and the next tungsten needle 115 switches from the first position state to the second position state, and so on. In this way, the plurality of tungsten needles 115 do not affect each other, thereby increasing the needle density, shortening the waiting time for the crystal, and being able to adapt to the different spacings between the chip pads on the substrate 33, thereby solving the current problems of low transfer efficiency and the needle density being restricted by the thickness of the needle rod.

[0043] A scanning camera 21 is provided on the side of the planar motion platform close to the multi-needle crystal piercing device, and a chip carrier 22 is provided on the planar motion platform. The chip carrier 22 is used to fix a blue film 223. Mini-LED chips are evenly distributed on the side of the blue film 223 away from the multi-needle crystal piercing device. The substrate 33 is provided with evenly arranged chip pads, and the chip pads are opposite to the Mini-LED chips. During operation, when single-area crystal piercing is performed, the chip is mainly driven by the planar motion platform to move to a position corresponding to the tungsten needle 115 and the chip pad. The planar motion platform has a small load and is easier to achieve high-frequency and high-speed movement. The multi-needle crystal piercing device has a large mass and is greatly limited in high-frequency and high-speed movement. The movement frequency of the multi-needle crystal piercing device is reduced by the movement of the planar motion platform, the vibration of the multi-needle crystal piercing device is reduced, the packaging accuracy is improved, and the problem of limited packaging accuracy is solved.

[0044] Furthermore, the motor 112 is fixedly installed on the top of the shell 111, the tungsten needle clamp 114 is penetrated through the shell 111, the driving end of the motor 112 is connected to the tungsten needle clamp 114, the sub-crystal head 11 also includes an elastic member 113, one end of the elastic member 113 is located below the tungsten needle clamp 114, and the other end of the elastic member 113 is fixed in the shell, the motor 112 drives the tungsten needle clamp 114 to compress the elastic member 113 downward and move to the second position state, and the elastic member 113 drives the tungsten needle clamp 114 to restore the first position state upward.

[0045] Specifically, Figure 5 As shown, the motor 112 is fixedly installed on the top of the shell 111, and the driving end of the motor 112 is connected to the tungsten needle clamp 114, driving the tungsten needle clamp 114 to move along the guide rail 1111. The tungsten needle clamp 114 is penetrated by the shell 111. During the movement of the tungsten needle clamp 114, the shell 111 can improve the stability of the tungsten needle clamp 114 and reduce the position deviation during the working process, thereby improving the stability of the shape position accuracy of the tungsten needle 115 and reducing the processing error.

[0046] Preferably, the sub-crystal piercing head 11 also includes an elastic member 113, one end of the elastic member 113 is located below the tungsten needle clamp 114, and the other end of the elastic member 113 is fixed in the shell. The motor 112 drives the tungsten needle clamp 114 to compress the elastic member 113 downward and move it to the second position state. The elastic member 113 drives the tungsten needle clamp 114 to restore the first position state upward. In the sub-crystal piercing head 11, only the motor 112 is needed to drive the tungsten needle clamp 114, which has a simple structure and is easy to operate, thereby reducing the complexity of multi-needle crystal piercing.

[0047] Preferably, the elastic member 113 is a coil spring with a compact structure. It can produce a large elastic deformation when loaded, converting mechanical work or kinetic energy into deformation energy, and can convert the deformation energy back to mechanical work or kinetic energy after unloading, with high energy conversion efficiency.

[0048] Furthermore, a slider 116 is provided between the elastic member 113 and the tungsten needle clamp 114 , and the slider 116 is slidably connected with the elastic member 113 and the tungsten needle clamp 114 . Two elastic members 113 are provided, and the two elastic members 113 are connected to both ends of the bottom of the slider 116 .

[0049] Specifically, because there is relative displacement between the tungsten needle clamp 114 and the elastic member 113, a slider 116 is provided between the elastic member 113 and the tungsten needle clamp 114, and the slider 116 is slidably connected with the elastic member 113 and the tungsten needle clamp 114, that is, the elastic member 113 and the tungsten needle clamp 114 are in contact through the slider 116, and the slider 116 transmits the elastic force of the elastic member 113 to the tungsten needle clamp 114, so that the tungsten needle clamp 114 can smoothly restore the first position state, avoiding direct contact between the elastic member 113 and the tungsten needle clamp 114, and preventing the elastic member 113 from damaging the tungsten needle clamp 114 when relative displacement occurs, which is convenient for later maintenance and enables the tungsten needle clamp 114 to move quickly and switch between the first position state and the second position state, thereby improving flexibility during work.

[0050] The two elastic members 113 are connected to the two ends of the bottom of the slider 116 , which can effectively maintain the horizontal balance of the tungsten needle clamp 114 and ensure that the tungsten needle clamp 114 can be quickly and accurately moved to the first position state.

[0051] Preferably, the crystal piercing head assembly 1 also includes a central crystal piercing head 14, which is located directly above the pin hole 121. The central crystal piercing head 14 includes a motor 112 and a central tungsten needle 141. The motor 112 drives the central tungsten needle 141 to vertically downwardly pass through the pin hole 121 and act on the blue film 223 on the chip carrier 22, or drives the central tungsten needle 141 to vertically upwardly exit the pin hole 121. The axis of the central tungsten needle 141 is colinear with the axis of the pin hole 121.

[0052] Specifically, Figure 6 As shown, the central crystal piercing head 14 is located directly above the pinhole 121, and the central crystal piercing head 14 includes a motor 112 and a central tungsten needle 141. The motor 112 drives the central tungsten needle 141 to vertically downwardly pass through the pinhole 121 and act on the blue film 223 on the chip carrier 22, or drives the central tungsten needle 141 to vertically upwardly exit the pinhole 121. The axis of the central tungsten needle 141 is colinear with the axis of the pinhole 121, and can quickly perform crystal piercing work, adapt to different arrangements, omit unnecessary movement processes and unnecessary errors, reduce costs, improve the flexibility of the device, and adapt to the needs of different chip arrangements.

[0053] Further, the guide rail 1111 is an arc-shaped guide rail, and a plurality of the sub-crystal heads 11 are arranged in an array;

[0054] The number of the sub-crystal heads 11 is 4, and the 4 sub-crystal heads 11 are distributed in a cross shape, and the center of the cross and the center of the pinhole 121 are located on the same vertical axis; or, the number of the sub-crystal heads 11 is 8, and the 8 sub-crystal heads 11 are evenly surrounded by the central crystal head 14, and the 8 sub-crystal heads 11 are distributed in a cross shape on the bottom plate 12, and the center of the cross and the center of the pinhole 121 are located on the same vertical axis.

[0055] Specifically, the guide rail 1111 is an arc-shaped guide rail, and the tungsten needle 115 performs a curved motion according to the guide rail 1111, that is, it not only has a vertical motion to pierce the Mini-LED chip and transfer it to the substrate 33, but also has a horizontal motion from a position far away from the Mini-LED chip to directly above the Mini-LED chip. The guide rail 1111 can be adjusted according to the requirements of the piercing crystal. In the vertical direction, the movement distance of the tungsten needle 115 can transfer the chip to the substrate 33; in the horizontal direction, the tungsten needles 115 will not affect each other when in the first position state, and reach the second position state, corresponding to the chip pad of the substrate 33. The guide rail 1111 is arc-shaped and has good adaptability. It can correspond to the different spacings of the chip pads of the substrate 33, reduce damage to the chip, and improve the yield rate.

[0056] In the crystal piercing head assembly 1, a plurality of the sub-crystal piercing heads 11 are arranged in an array, such as Figure 4 As shown, the number of the sub-crystal heads 11 is 4, and the 4 sub-crystal heads 11 are distributed in a cross shape, and the center of the cross and the center of the pinhole 121 are located on the same vertical axis; or Figure 2 As shown, the number of the sub-crystal heads 11 is 8, and the 8 sub-crystal heads 11 are evenly surrounded by the central crystal head 14. The 8 sub-crystal heads 11 are distributed in a cross shape on the bottom plate 12, and the center of the cross shape and the center of the pinhole 121 are located on the same vertical axis. When in use, the tungsten needle 115 needs to reach the "tungsten needle-chip-chip pad" three-point line, and a number of the sub-crystal heads 11 are arranged in an array, that is, the tungsten needles 115 have been one-to-one correspondence with the chip pads of the substrate 33. It only needs to move the planar motion platform on the horizontal plane to match the Mini-LED chip attached to the blue film 223 with the chip pad of the substrate 33. By driving the corresponding tungsten needles 115, the purpose of transferring the chip can be achieved, the movement frequency of the crystal head assembly 1 can be reduced, the accuracy can be improved, and the process is fast, which improves the transfer packaging efficiency.

[0057] Furthermore, the guide rails 1111 are through grooves oppositely arranged on both sides of the shell 111 , guide rods 1141 are arranged on both sides of the tungsten needle clamp 114 , the axes of the two guide rods 1141 are located on the same line, and the guide rods 1141 are slidably clamped in the guide rails 1111 .

[0058] Specifically, the guide rail 1111 is a through groove arranged opposite to each other on both sides of the shell 111, and guide rods 1141 are coaxially arranged on both sides of the tungsten needle clamp 114. The guide rods 1141 are slidably clamped in the guide rail 1111. When the tungsten needle 115 is in the first position state or the second position state, the guide rod 1141 is located at the end of the guide rail 1111. At this time, the guide rail 1111 can limit the movement position of the needle head, ensuring that the needle head can accurately complete the chip transfer without damaging the chip; the guide rod 1141 can drive the tungsten needle clamp 114 to move according to the trajectory of the guide rail 1111, and then drive the tungsten needle 115 to move along a precise path, reducing the vibration and deviation of the tungsten needle 115 during the movement process, enhancing the stability of the system, and ensuring that the plurality of tungsten needles 115 will not affect each other, ensuring the needle output density, reducing wear to a certain extent, and extending the service life of the equipment.

[0059] A method for using the multi-needle mechanical pricking Mini-LED mass transfer system comprises the following steps:

[0060] S1. Substrate preparation: Place the substrate 33 to be processed on the transport track 31. When transported to the thorn crystal position, the transport track 31 stops moving, the stopper pops up, and the substrate 33 is accurately fixed at the thorn crystal position. The negative pressure suction cup 32 rises and adheres to the lower surface of the substrate 33 to fix the substrate 33;

[0061] S2, chip preparation: fix the blue film 223 on the chip carrier 22, and the planar motion platform drives the chip carrier 22 to the bottom of the scanning camera 21. The scanning camera 21 obtains the positions of all Mini-LED chips through machine vision and stores the records. After completion, the chip carrier 22 moves to the top of the substrate 33;

[0062] S3, single-area crystal piercing: the crystal piercing head assembly 1 is driven by the three-axis motion gantry 13 to reach the crystal piercing area to be processed, and the crystal piercing area to be processed contains an m×n dot matrix, and the dot matrix corresponds to the chip pad 341 of the substrate 33 and the needle exit position of the sub-crystal piercing head 11 one by one; the first point of the dot matrix is ​​selected, and according to the recorded chip position, the planar motion platform drives the chip corresponding to the point to move to the position of "tungsten needle-chip-chip pad" three points and one line, and the first tungsten needle 115 reaches the second position state under the drive of the corresponding motor 112 to complete the crystal piercing movement. When the first tungsten needle completes the crystal piercing movement, the second tungsten needle switches to the second position state under the drive of the corresponding motor, and at this time, the first tungsten needle switches to the first position state. When the second tungsten needle completes the crystal piercing movement, the third tungsten needle switches to the second position state under the drive of the corresponding motor, and at this time, the second tungsten needle switches to the first position state, and so on, to complete the transfer of all chips in the area to be processed;

[0063] S4, positioning transfer: After completing the crystallization of a single area, the multi-needle crystallization device moves to the next area to be crystallized for alignment. After completing the alignment, step S3 is repeated to perform crystallization transfer until all the Mini-LED chips are crystallized.

[0064] The present technical solution also proposes a method of using the above-mentioned multi-needle mechanical thorn crystal type Mini-LED mass transfer system, which can complete the transfer of Mini-LED chips using the above-mentioned multi-needle mechanical thorn crystal type Mini-LED mass transfer system. Through the arrangement of several of the sub-thorn crystal heads 11 and the central thorn crystal head 14, several of the tungsten needles 115 move according to the guide rail 1111, and there is no conflict between the tungsten needles 115; the movement of multiple tungsten needles 115 improves the transfer efficiency, and when transferring chips in the same area to be processed, only the chip carrier 22 needs to perform planar movement, and the thorn crystal head assembly 1 does not need to move. Compared with the thorn crystal head assembly 1, the load of the planar motion platform is low, which reduces the movement frequency of the thorn crystal head assembly 1, can effectively improve the packaging accuracy, and solve the current problems of low Mini-LED chip transfer efficiency and limited packaging accuracy.

[0065] Further, in step S3, the planar motion platform drives the chip carrier 22 to perform two-dimensional motion, thereby driving the chip adhered to the blue film 223 to move to a desired position, and the movement route of the chip carrier 22 is an "S"-shaped line.

[0066] Specifically, the Mini-LED chips are evenly distributed on the blue film 223, and the planar motion platform drives the chip corresponding to the first point to move to the position of the three points of "tungsten needle-chip-chip pad" (such as Figure 7 As shown), after completing the transfer of the chip on the corresponding point, the planar motion platform drives the chip carrier 22 to move, and after completing the transfer of the chip pads on the substrate 33 in a row where the point is located, the chip is driven to move to another row of points adjacent to the last point in this row to continue chip transfer. The overall line is an "S" shape, which reduces the moving distance of the planar motion platform and improves the transfer speed.

[0067] Preferably, the Mini-LED chip is rectangular, the long side of the Mini-LED chip is larger than 50 μm, and the short side is larger than 25 μm; the spacing between the chip pads 341 is 100-1000 microns.

[0068] Specifically, the long side size of the Mini-LED chip is greater than 50μm, and the short side size is greater than 25μm. If the size of the Mini-LED chip is smaller than the above range, it is not suitable to use the mechanical pricking method, and the chip is easily damaged. The distance between the chip pads 341 should be greater than the size of the chip, and the needle size of the tungsten needle 115 is slightly larger than the chip size. The spacing between the chip pads 341 is 100-1000 microns, which is the spacing range used during operation. 100 microns is limited by the size of the Mini-LED chip itself. If the spacing between the chip pads 341 is greater than 1000 microns, the movement distance of the planar motion platform increases, and the time consumed becomes longer, which in turn affects the transfer efficiency. Controlling between 100-1000 microns can adapt to Mini-LED chips while minimizing the impact on the transfer rate.

[0069] Preferably, the vacuum degree of the negative pressure suction cup 32 is less than 100 Pa. During mechanical crystallization, the substrate 33 needs to be subjected to the high-frequency impact of the tungsten needle 115 , and thus needs to be fixed with a relatively large negative pressure to prevent the substrate 33 from being displaced.

[0070] The present invention is further described below in conjunction with embodiments.

[0071] Example 1

[0072] like Figure 1 As shown, a multi-needle mechanical thorn crystal type Mini-LED mass transfer system includes a substrate assembly line, a planar motion platform and a multi-needle thorn crystal device; a scanning camera 21 is provided on the side of the planar motion platform close to the multi-needle thorn crystal device, and a chip carrier 22 is provided on the planar motion platform, and the chip carrier 22 is used to fix a blue film 223.

[0073] The multi-needle crystal piercing device includes a crystal piercing head assembly 1 and a three-axis motion gantry 13, wherein the crystal piercing head assembly 1 is fixed on the three-axis motion gantry 13, and the crystal piercing head assembly 1 is driven by the three-axis motion gantry 13; the crystal piercing head assembly 1 includes a base plate 12 and a plurality of sub-crystal piercing heads 11, wherein the base plate 12 is provided with a needle hole 121, and the plurality of sub-crystal piercing heads 11 are distributed around the periphery of the needle hole 121; the sub-crystal piercing heads 11 include a shell 111, a motor 112 and a tungsten needle clamp 114, wherein the shell 111 is provided with a guide rail 1111, and the tungsten needle clamp 114 is arranged on the guide rail 1111 to guide and slide along the guide rail 1111. The housing 111, the motor 112 drives the tungsten needle clamp 114 to move along the guide rail 1111, the tungsten needle clamp 114 is provided with a tungsten needle 115, the movement of the tungsten needle clamp 114 enables the tungsten needle 115 to switch between a first position state and a second position state, when the tungsten needle 115 is in the first position state, the tungsten needle 115 does not pass through the pin exit hole 121, the axis of the tungsten needle 115 is not colinear with the axis of the pin exit hole 121, when the tungsten needle 115 switches to the second position state, the tungsten needle 115 passes through the pin exit hole 121 and acts on the blue film 223 on the chip carrier 22.

[0074] The substrate assembly line is located on the side of the planar motion platform away from the multi-needle crystal piercing device, and the substrate assembly line includes a transport track 31, a limiter and a negative pressure suction cup 32. The transport track 31 is used to transport the substrate 33 to the desired position, the limiter is located on both sides of the transport track 31, and the negative pressure suction cup 32 is located in the middle of the transport track 31. The limiter and the negative pressure suction cup 32 are used to fix the substrate 33.

[0075] The method of using the multi-needle mechanical thorn crystal Mini-LED mass transfer system comprises the following steps:

[0076] S1. Substrate preparation: Place the substrate 33 to be processed on the transport track 31. When transported to the thorn crystal position, the transport track 31 stops moving, the stopper pops up, and the substrate 33 is accurately fixed at the thorn crystal position. The negative pressure suction cup 32 rises and adheres to the lower surface of the substrate 33 to fix the substrate 33;

[0077] S2. Chip preparation: fix the blue film 223 on the chip carrier 22, and the planar motion platform drives the chip carrier 22 to the bottom of the scanning camera 21. The scanning camera 21 obtains the positions of all Mini-LED chips through machine vision and stores the records. After completion, the chip carrier 22 moves to the top of the substrate 33.

[0078] S3. Single-area crystal piercing: The crystal piercing head assembly 1 is driven by the three-axis motion gantry 13 to reach the area to be pierced, and the area to be pierced contains a 3×3 dot matrix, and the dot matrix corresponds one-to-one with the chip pad 341 of the substrate 33 and the needle outlet position of the sub-crystal piercing head 11; the first point of the dot matrix is ​​selected, and according to the recorded chip position, the planar motion platform drives the chip corresponding to the point to move to the position of "tungsten needle-chip-chip pad" three points and one line, and the first tungsten needle 115 reaches the second position state under the drive of the corresponding motor 112 to complete the crystal piercing movement. When the first tungsten needle completes the crystal piercing movement, the second tungsten needle switches to the second position state under the drive of the corresponding motor, and at this time the first tungsten needle switches to the first position state, and when the second tungsten needle completes the crystal piercing movement, the third tungsten needle switches to the second position state under the drive of the corresponding motor, and at this time the second tungsten needle switches to the first position state, and so on, to complete the transfer of all chips in the area to be processed.

[0079] S4, positioning transfer: After completing the crystallization of a single area, the multi-needle crystallization device moves to the next area to be crystallized for alignment. After completing the alignment, step S3 is repeated to perform crystallization transfer until all the Mini-LED chips are crystallized.

[0080] Example 2

[0081] A multi-needle mechanical pricking crystal type Mini-LED mass transfer system includes a substrate assembly line, a planar motion platform and a multi-needle pricking crystal device; a scanning camera 21 is provided on the side of the planar motion platform close to the multi-needle pricking crystal device, and a chip carrier 22 is provided on the planar motion platform, and the chip carrier 22 is used to fix a blue film 223.

[0082] The multi-needle crystal piercing device includes a crystal piercing head assembly 1 and a three-axis motion gantry 13, wherein the crystal piercing head assembly 1 is fixed on the three-axis motion gantry 13, and the crystal piercing head assembly 1 is driven by the three-axis motion gantry 13; the crystal piercing head assembly 1 includes a base plate 12 and a plurality of sub-crystal piercing heads 11, wherein the base plate 12 is provided with a needle hole 121, and the plurality of sub-crystal piercing heads 11 are distributed around the periphery of the needle hole 121; the sub-crystal piercing heads 11 include a shell 111, a motor 112 and a tungsten needle clamp 114, wherein the shell 111 is provided with a guide rail 1111, and the tungsten needle clamp 114 is arranged on the guide rail 1111 to guide and slide along the guide rail 1111. The housing 111, the motor 112 drives the tungsten needle clamp 114 to move along the guide rail 1111, the tungsten needle clamp 114 is provided with a tungsten needle 115, the movement of the tungsten needle clamp 114 enables the tungsten needle 115 to switch between a first position state and a second position state, when the tungsten needle 115 is in the first position state, the tungsten needle 115 does not pass through the pin exit hole 121, the axis of the tungsten needle 115 is not colinear with the axis of the pin exit hole 121, when the tungsten needle 115 switches to the second position state, the tungsten needle 115 passes through the pin exit hole 121 and acts on the blue film 223 on the chip carrier 22.

[0083] The substrate assembly line is located on the side of the planar motion platform away from the multi-needle crystal piercing device, and the substrate assembly line includes a transport track 31, a limiter and a negative pressure suction cup 32. The transport track 31 is used to transport the substrate 33 to the desired position, the limiter is located on both sides of the transport track 31, and the negative pressure suction cup 32 is located in the middle of the transport track 31. The limiter and the negative pressure suction cup 32 are used to fix the substrate 33.

[0084] The method of using the multi-needle mechanical thorn crystal Mini-LED mass transfer system comprises the following steps:

[0085] S1. Substrate preparation: Place the substrate 33 to be processed on the transport track 31. When transported to the thorn crystal position, the transport track 31 stops moving, the stopper pops up, and the substrate 33 is accurately fixed at the thorn crystal position. The negative pressure suction cup 32 rises and adheres to the lower surface of the substrate 33 to fix the substrate 33;

[0086] S2. Chip preparation: fix the blue film 223 on the chip carrier 22, and the planar motion platform drives the chip carrier 22 to the bottom of the scanning camera 21. The scanning camera 21 obtains the positions of all Mini-LED chips through machine vision and stores the records. After completion, the chip carrier 22 moves to the top of the substrate 33.

[0087] S3. Single-area crystal piercing: The crystal piercing head assembly 1 is driven by the three-axis motion gantry 13 to reach the area to be pierced, and the area to be pierced contains a 2×2 dot matrix, and the dot matrix corresponds one-to-one to the chip pad 341 of the substrate 33 and the needle outlet position of the sub-crystal piercing head 11; the first point of the dot matrix is ​​selected, and according to the recorded chip position, the planar motion platform drives the chip corresponding to the point to move to the position of "tungsten needle-chip-chip pad" three points and one line, and the first tungsten needle 115 reaches the second position state under the drive of the corresponding motor 112 to complete the crystal piercing movement. When the first tungsten needle completes the crystal piercing movement, the second tungsten needle switches to the second position state under the drive of the corresponding motor, and at this time the first tungsten needle switches to the first position state, and when the second tungsten needle completes the crystal piercing movement, the third tungsten needle switches to the second position state under the drive of the corresponding motor, and at this time the second tungsten needle switches to the first position state, and so on, to complete the transfer of all chips in the area to be processed.

[0088] S4, positioning transfer: After completing the crystallization of a single area, the multi-needle crystallization device moves to the next area to be crystallized for alignment. After completing the alignment, step S3 is repeated to perform crystallization transfer until all the Mini-LED chips are crystallized.

[0089] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the scope of protection of the present invention.

Claims

1. A multi-needle mechanical pricking crystal Mini-LED mass transfer system, characterized by: It includes a substrate assembly line, a plane motion platform and a multi-needle crystal piercing device; A scanning camera is provided on one side of the planar motion platform close to the multi-needle crystal pricking device, and a chip carrier is provided on the planar motion platform, and the chip carrier is used to fix the blue film; The multi-needle crystal piercing device includes a crystal piercing head assembly and a three-axis motion gantry, wherein the crystal piercing head assembly is fixed at the output end of the three-axis motion gantry, and the crystal piercing head assembly is driven by the three-axis motion gantry; the crystal piercing head assembly includes a bottom plate and a plurality of sub-crystal piercing heads, wherein the bottom plate is provided with a pin hole, and the plurality of sub-crystal piercing heads are distributed around the periphery of the pin hole; the sub-crystal piercing heads include a shell, a motor and a tungsten needle clamp, wherein the shell is provided with a guide rail, and the tungsten needle clamp is slidably arranged on the shell along the guide rail, and the motor drives the tungsten needle clamp to move along the guide rail, and the tungsten needle clamp is provided with a tungsten needle, and the movement of the tungsten needle clamp enables the tungsten needle to switch between a first position state and a second position state, and when the tungsten needle is in the first position state, the tungsten needle does not pass through the pin hole, and the axis of the tungsten needle is not colinear with the axis of the pin hole, and when the tungsten needle is switched to the second position state, the tungsten needle passes through the pin hole and acts on the blue film on the chip carrier; The substrate assembly line is located on the side of the planar motion platform away from the multi-needle crystal piercing device. The substrate assembly line includes a transport track, a limiter and a negative pressure suction cup. The transport track is used to transport the substrate to the desired position. The limiter is located on both sides of the transport track. The negative pressure suction cup is located in the middle of the transport track. The limiter and the negative pressure suction cup are used to fix the substrate.

2. The multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 1, characterized in that: The motor is fixedly mounted on the top of the shell, the tungsten needle clamp is passed through the shell, the driving end of the motor is connected to the tungsten needle clamp, the sub-crystal head also includes an elastic member, one end of the elastic member is located below the tungsten needle clamp, and the other end of the elastic member is fixed in the shell, the motor drives the tungsten needle clamp to compress the elastic member downward and move to the second position state, and the elastic member drives the tungsten needle clamp to restore the first position state upward.

3. The multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 2, characterized in that: A slider is provided between the elastic member and the tungsten needle clamp, and the slider is slidably connected with the elastic member and the tungsten needle clamp. Two elastic members are provided, and the two elastic members are connected with two ends of the bottom of the slider.

4. The multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 1, characterized in that: The crystal piercing head assembly also includes a central crystal piercing head, which is located directly above the pinhole. The central crystal piercing head includes a motor and a central tungsten needle. The motor drives the central tungsten needle vertically downward through the pinhole and acts on the blue film on the chip carrier, or drives the central tungsten needle vertically upward to exit the pinhole. The axis of the central tungsten needle is colinear with the axis of the pinhole.

5. The multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 4, characterized in that: The guide rail is an arc-shaped guide rail, and a plurality of the sub-thorn crystal heads are arranged in an array; The number of the sub-thorn crystal heads is 4, and the 4 sub-thorn crystal heads are distributed in a cross shape, and the center of the cross and the center of the pinhole are located on the same vertical axis; or, the number of the sub-thorn crystal heads is 8, and the 8 sub-thorn crystal heads are evenly surrounded by the central thorn crystal head, and the 8 sub-thorn crystal heads are distributed in a cross shape on the bottom plate, and the center of the cross and the center of the pinhole are located on the same vertical axis.

6. The multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 5, characterized in that: The guide rails are through grooves arranged opposite to each other on both sides of the housing. Guide rods are arranged on both sides of the tungsten needle clamp. The axes of the two guide rods are located on the same line. The guide rods are slidably clamped in the guide rails.

7. A method for using the multi-needle mechanical pricking Mini-LED mass transfer system according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Substrate preparation: Place the substrate to be processed on the transport track. When it is transported to the thorn crystal position, the transport track stops moving, the limiter pops up, and the substrate is accurately fixed at the thorn crystal position. The negative pressure suction cup rises and adheres to the lower surface of the substrate to fix the substrate; S2. Chip preparation: fix the blue film on the chip carrier, and the planar motion platform drives the chip carrier to the bottom of the scanning camera. The scanning camera obtains the position of all Mini-LED chips through machine vision and stores the records. After completion, the chip carrier moves to the top of the substrate; S3, single-area crystal piercing: the crystal piercing head assembly is driven by the three-axis motion gantry to reach the crystal piercing area to be pierced, and the crystal piercing area to be pierced contains an m×n dot matrix, and the dot matrix corresponds one by one to the chip pads of the substrate and the needle positions of the sub-crystal piercing heads; The first point of the dot matrix is ​​selected, and according to the recorded chip position, the plane motion platform drives the chip corresponding to the point to move to the position of the three points of "tungsten needle-chip-chip pad". The first tungsten needle reaches the second position state under the drive of the corresponding motor and completes the crystal pricking movement. When the first tungsten needle completes the crystal pricking movement, the second tungsten needle switches to the second position state under the drive of the corresponding motor. At this time, the first tungsten needle switches to the first position state. When the second tungsten needle completes the crystal pricking movement, the third tungsten needle switches to the second position state under the drive of the corresponding motor. At this time, the second tungsten needle switches to the first position state, and so on, to complete the transfer of all chips in the area to be processed; S4, positioning transfer: After completing the crystallization of a single area, the multi-needle crystallization device moves to the next area to be crystallized for alignment. After completing the alignment, step S3 is repeated to perform crystallization transfer until all the Mini-LED chips are crystallized.

8. The method for using the multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 7, characterized in that: In step S3, the planar motion platform drives the chip carrier to perform two-dimensional motion, thereby driving the chip adhered to the blue film to move to a desired position, and the movement route of the chip carrier is an "S"-shaped line.

9. The method for using a multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 7, characterized in that: The Mini-LED chip is rectangular, the long side of the Mini-LED chip is greater than 50 μm, and the short side is greater than 25 μm; the spacing between the chip pads is 100-1000 microns.

10. The method for using a multi-needle mechanical thorn crystal Mini-LED mass transfer system according to claim 7, characterized in that: The vacuum degree of the negative pressure suction cup is less than 100Pa.

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