Micro LED chip transfer device and transfer method

Abstract

The present invention provides a transfer device and a transfer method for a Micro LED chip, comprising: a machine for carrying and conveying a target substrate; a temporary substrate for temporarily carrying a Micro LED chip; a thorn wheel, comprising at least 3 thorn needles, the thorn needles being used to detach the Micro LED chip from the temporary substrate and transfer it to the target substrate; a pulley for conveying the temporary substrate; during the transfer process of the Micro LED chip, the thorn wheel and the pulley are located above the machine and on the side of the temporary substrate away from the Micro LED chip. By adopting the transfer device provided by the present invention and implementing the transfer method provided by the present invention, the Micro LED chip can be transferred, and a transfer efficiency of one million chips per hour can be achieved, thereby improving the transfer efficiency of the Micro LED chip, thereby improving the production efficiency of the Micro LED display screen and reducing the production cost.

Description

Technical Field

[0001] The present application relates to the display field, and in particular to a transfer device and a transfer method for a Micro LED chip. Background Art

[0002] Micro Light Emitting Diode (Micro LED) display screens have always been a key research topic in the display field due to their advantages such as high brightness, high contrast, high color gamut, high efficiency, and high reliability.

[0003] However, since the production process of Micro LED displays requires transferring millions of Micro LED chips to the array substrate through mechanical transfer and other means, this transfer method has low transfer efficiency, resulting in low production efficiency and high production costs of Micro LED displays. Summary of the invention

[0004] The present invention provides a transfer device and a transfer method for a Micro LED chip, so as to improve the transfer efficiency of the Micro LED chip, thereby improving the production efficiency of the Micro LED display screen and reducing the production cost.

[0005] To solve the above problems, the technical solution provided by the present invention is as follows:

[0006] The present invention provides a transfer device for a Micro LED chip, the transfer device for a Micro LED chip comprising:

[0007] A machine platform, used for carrying and conveying a target substrate;

[0008] Temporary substrate, used to temporarily carry Micro LED chips;

[0009] A pricking wheel, comprising at least three pricking needles, wherein the pricking needles are used to detach the Micro LED chip from the temporary substrate and transfer it to the target substrate;

[0010] A pulley, used for conveying the temporary substrate;

[0011] During the transfer process of the Micro LED chip, the spur wheel and the pulley are located above the machine platform and on a side of the temporary substrate away from the Micro LED chip.

[0012] Optionally, in some embodiments of the present invention, the thorn wheel includes a hub and the thorn needle, and the thorn needle is arranged on the outer periphery of the hub.

[0013] Optionally, in some embodiments of the present invention, the top of the needle is a plane, a spherical surface, or a convex curved surface.

[0014] Optionally, in some embodiments of the present invention, the tip diameter of the needle is less than 20 microns, and the height of the needle is greater than 10 microns.

[0015] Optionally, in some embodiments of the present invention, the temporary substrate is a conveyor belt, and the conveyor belt includes an adhesive layer. The adhesive layer is located on the surface of the conveyor belt carrying the Micro LED chip, and is used for sticking and fixing the Micro LED chip.

[0016] Optionally, in some embodiments of the present invention, the temporary substrate is a conveyor chain, the conveyor chain includes a groove and an opening, the groove is provided on a side of the conveyor chain carrying the Micro LED chip, for accommodating and fixing the Micro LED chip, and the opening is connected to the groove and runs through the conveyor chain.

[0017] Optionally, in some embodiments of the present invention, the height H of the needle is greater than the depth L of the opening, and the diameter of the needle from the top to the root L is smaller than the caliber of the opening.

[0018] Optionally, in some embodiments of the present invention, the pulley comprises an active transmission wheel, and the active transmission wheel and the spur wheel jointly transmit the temporary substrate.

[0019] Optionally, in some embodiments of the present invention, the pulley includes an active transmission wheel and a driven transmission wheel, the active transmission wheel and the driven transmission wheel are located on both sides of the thorn wheel, and the tip of the thorn needle protrudes from the transmission plane of the active transmission wheel and the driven transmission wheel.

[0020] Accordingly, the present invention further provides a method for transferring a Micro LED chip, wherein the transfer device described in any one of the embodiments of the present invention is used to implement the steps of the transfer method, and the transfer method includes:

[0021] Transferring the pre-arranged Micro LED chips to the temporary substrate;

[0022] The temporary substrate is transferred by the pulley, and the target substrate is transferred by the machine. Meanwhile, the Micro LED chip on the temporary substrate is transferred to the target substrate by rotating the thorn wheel. The linear speeds of the pulley, the machine, and the thorn wheel are equal.

[0023] The present invention provides a transfer device and a transfer method for a Micro LED chip. By adopting the transfer device provided in the embodiment of the present invention and implementing the transfer method provided in the embodiment of the present invention, the Micro LED chip can be transferred, and the transfer efficiency of one million chips per hour can be easily achieved, which greatly improves the transfer efficiency of the Micro LED chip, thereby improving the production efficiency of the Micro LED display screen and reducing the production cost. In addition, by adjusting the diameter of the hub in the transfer device, the number and distribution distance of the needles, the transfer process of Micro LED chips of different sizes and spacings can be realized, which has good flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The technical solution and other beneficial effects of the present application will be made apparent by describing in detail the specific implementation methods of the present application in conjunction with the accompanying drawings.

[0025] Figure 1 A schematic diagram of a first structure of a Micro LED chip transfer device provided in an embodiment of the present invention;

[0026] Figure 2 for Figure 1 A magnified schematic diagram of the middle 101 area;

[0027] Figure 3 A schematic diagram of a second structure of the Micro LED chip transfer device provided in an embodiment of the present invention;

[0028] Figure 4 for Figure 3 A magnified schematic diagram of the middle 301 area;

[0029] Figure 5 Flow chart of a method for transferring a Micro LED chip provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the specific embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments and / or examples of the present invention. Obviously, the embodiments and / or examples described below are only part of the embodiments and / or examples of the present invention, rather than all the embodiments and / or examples. Based on the embodiments and / or examples in the present invention, all other embodiments and / or examples obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The directional terms mentioned in the present invention, such as [upper], [lower], [left], [right], [front], [back], [inner], [outer], [side], etc., are only referenced to the directions of the attached drawings. Therefore, the directional terms used are used to illustrate and understand the present invention, rather than to limit the present invention. The terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0032] In one embodiment, the present invention provides a transfer device for Micro LED chips for mass transfer of the Micro LED chips, thereby improving the transfer efficiency of the Micro LED chips and further improving the production efficiency of the Micro LED display. Figures 1 to 4 , the transfer device comprises:

[0033] The machine 10 is used to carry and transfer the target substrate 20;

[0034] A temporary substrate 30, used for temporarily carrying the Micro LED chip 40;

[0035] The thorn wheel 50 includes at least three thorn needles 51, and the thorn needles 51 are used to separate the Micro LED chip 40 from the temporary substrate 30 and transfer it to the target substrate 20;

[0036] A pulley, used to transport the temporary substrate 30;

[0037] During the transfer process of the Micro LED chip 40 , the lance 50 and the pulley are located above the platform 10 and on a side of the temporary substrate 30 away from the Micro LED chip 40 .

[0038] Specifically, the target substrate 20 is usually a thin film transistor array substrate TFT, and a driving circuit is provided in the thin film transistor array substrate. After the Micro LED chip 40 is bound to the target substrate 20, the driving circuit is used to drive the Micro LED chip 40 to emit light. The driving circuit includes a plurality of sub-driving circuits arranged in an array. The group driving circuit corresponds to the Micro LED chip 40 one-to-one or one-to-many. Therefore, the Micro LED chip 40 needs to be transferred to a predetermined position of the target substrate 20 as required to achieve electrical connection with the sub-driving circuit.

[0039] The temporary substrate 30 is used to temporarily carry the Micro LED chip 40 and has the function of fixing the temporary substrate 30. Figure 1 and Figure 2 , Figure 1 A first structural schematic diagram of the transfer device provided in an embodiment of the present invention is shown. Figure 2 Shows Figure 1 In the enlarged schematic diagram of the area 101, the temporary substrate 30 is a conveyor belt, and the conveyor belt includes an adhesive layer, and the adhesive layer is located on the surface of the conveyor belt carrying the Micro LED chip, that is, Figure 1 and Figure 2 The adhesive layer is used to adhere and fix the Micro LED chip on the lower surface of the conveyor belt. Figure 3 and Figure 4 , Figure 3 A second structural schematic diagram of the transfer device provided in an embodiment of the present invention is shown, Figure 4 Shows Figure 3 In the enlarged schematic diagram of the area 301, the temporary substrate 30 is a conveyor chain, and the conveyor chain includes a groove 31. The groove 31 is provided on the side of the conveyor chain that carries the Micro LED chip, and is used to accommodate and fix the Micro LED chip. Further, the conveyor chain also includes an opening 32, and the opening 32 is connected to the groove 31 and passes through the conveyor chain, and the center line of the opening 32 coincides with the center line of the groove 31. In one embodiment, the diameter of the opening 32 is smaller than the diameter of the groove 31, so that the bottom surface of the groove 31 can support the Micro LED chip; in another embodiment, the diameter of the opening 32 can also be greater than or equal to the diameter of the groove 31, and the Micro LED chip is supported and fixed by the side wall of the groove.

[0040] The thorn wheel 50 includes a hub 52 and a thorn needle 51, and the thorn needle 51 is arranged on the outer periphery of the hub 52. The thorn needle 51 and the hub 52 can be arranged in an integral manner or in a separate manner. The hub 52 is usually a rigid hub made of metal material. When the thorn needle 51 and the hub 52 are arranged in an integral manner, the material of the thorn needle 51 and the hub 52 is preferably a nickel alloy; when the thorn needle 51 and the hub 52 are arranged in a separate manner, the material of the thorn needle 51 can be selected from hard organic materials. Compared with inorganic rigid materials, hard organic materials have a lower hardness. Therefore, while maintaining the shape of the thorn needle 51, the risk of damage to the Micro LED chip by the thorn needle 51 can be reduced. Furthermore, the top of the thorn needle 51 is a plane, a spherical surface or a convex curved surface, which further reduces the risk of damage to the Micro LED chip by the thorn needle 51 compared to the top being in the shape of a needle tip. The diameter of the hub 52 is greater than 0.5 cm to ensure that enough needles can be arranged on the periphery of the hub 52. The top diameter of the needle 51 is less than 20 microns, the height H of the needle is greater than 10 microns, the height H of the needle 51 is greater than the depth L of the opening, and the diameter of the needle 51 from the top to the root L is smaller than the caliber of the opening 32, so as to ensure that the needle 51 can pass through the opening 32 and contact the Micro LED chip during the transfer of the Micro LED chip. In the rotation direction of the thorn wheel 50, the number of the needles 51 is greater than or equal to 3, and the distance between two adjacent needles 51 is the same to match the spacing of the Micro LED chip. Further, the linear distance between the top centers of two adjacent needles 51 is the same as the center distance between two adjacent Micro LED chips on the temporary substrate, and the linear distance is the distance between the top centers of two adjacent needles 51 on the spherical surface where the tops of the needles 51 are located. When the temporary substrate 30 is a conveyor chain, the linear distance between the top centers of the two adjacent needles 51 is the same as the center distance between the two adjacent openings 32 .

[0041] The pulley is used to transport the temporary substrate 30. In one embodiment, please refer to Figure 1 and Figure 2 The pulley includes a driving transmission wheel 61 and a driven transmission wheel 62, the driving transmission wheel 61 and the driven transmission wheel 62 are located on both sides of the thorn wheel 50, preferably the thorn needle 51 is located in the middle of the driving transmission wheel 61 and the driven transmission wheel 62, the top of the thorn needle 51 protrudes from the transmission plane of the driving transmission wheel 61 and the driven transmission wheel 62, and the transmission plane is parallel to the plane of the machine 10. In another embodiment, please refer to Figure 3 and Figure 4The pulley only includes an active transmission wheel 61, which is located at the transmission starting end of the temporary substrate 30, and the spur wheel 50 is located at the other end of the temporary substrate 30. The active transmission wheel 61 and the spur wheel 50 transmit the temporary substrate 30 together.

[0042] Accordingly, the embodiment of the present invention further provides a method for transferring a Micro LED chip, and the steps of the transfer method are implemented by using the transfer device described in any embodiment of the present invention. Figure 5 , Figure 5 A flow chart of a method for transferring a Micro LED chip provided by an embodiment of the present invention is shown, and the method for transferring comprises:

[0043] Step S1, transferring the pre-arranged Micro LED chips to a temporary substrate;

[0044] Step S1, using the pulley to transfer the temporary substrate, using the machine to transfer the target substrate, and at the same time, the spur wheel rotates to transfer the Micro LED chip on the temporary substrate to the target substrate; the linear speeds of the pulley, the machine, and the spur wheel are kept equal.

[0045] Specifically, when the temporary substrate is the conveyor belt, the step S1 of transferring the pre-arranged Micro LED chips to the temporary substrate is specifically transferring the pre-arranged Micro LED chips to the adhesive layer for pasting and fixing. During this process, the relative positional relationship between the Micro LED chips remains unchanged. When the temporary substrate is the conveyor chain, the step S1 of transferring the pre-arranged Micro LED chips to the temporary substrate is specifically transferring the pre-arranged Micro LED chips to the groove 31 for accommodation and fixing. Similarly, during this process, the relative positional relationship between the Micro LED chips remains unchanged.

[0046] In step S2, the temporary substrate is transmitted by the pulley specifically by rotating the active transmission wheel 61, driving the temporary substrate to be transmitted forward, that is, to the direction of the thorn wheel 50 in the figure; the target substrate is transmitted by the machine 10 specifically by transmitting the target in the direction of the active transmission wheel 61 through the machine; the Micro LED chip on the temporary substrate is transferred to the target substrate by rotating the thorn wheel specifically by the thorn wheel 50 rotating, and the thorn wheel 50 acts on the conveying belt or the Micro LED chip 40 through the thorn needle 51 protruding from the conveying surface of the temporary substrate 30, so that the Micro LED chip 40 is detached from the temporary substrate 30 and falls on the target substrate 20; the rotation of the active transmission wheel 61, the transmission of the machine 10 and the rotation of the thorn wheel 50 are carried out simultaneously, and the rotation linear speed of the active transmission wheel 61, the linear speed of the machine 10 and the linear speed of the thorn wheel 50 are equal.

[0047] In one embodiment, when the rotation speed of the thorn wheel r = 8000 rpm, and the number of the thorn needles 51 and the thorn wheel 50 in the rotation direction is 500, when the transfer device provided by the embodiment of the present invention is used to transfer the Micro LED chip, the transfer rate v of the Micro LED chip can reach 2.4 million pieces / hour.

[0048] In summary, the embodiments of the present invention provide a transfer device and a transfer method for a Micro LED chip. By adopting the transfer device provided by the embodiments of the present invention and implementing the transfer method provided by the embodiments of the present invention, the Micro LED chip can be transferred, and a transfer efficiency of one million chips per hour can be easily achieved, which greatly improves the transfer efficiency of the Micro LED chip, thereby improving the production efficiency of the Micro LED display screen and reducing the production cost. In addition, by adjusting the diameter of the hub in the transfer device, the number and distribution distance of the needles, the transfer process of Micro LED chips of different sizes and spacings can be realized, with good flexibility. It should be noted that the embodiments provided by the present invention are not limited to the transfer of Micro LED chips, but are also suitable for the transfer of Mini LED chips and the mass transfer of other small-sized devices.

[0049] The transfer device and transfer method of the Micro LED chip provided in the embodiments of the present invention are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A device for transferring a Micro LED chip, characterized in that: include: A machine platform, used for carrying and conveying a target substrate; Temporary substrate, used to temporarily carry Micro LED chips; A pricking wheel, comprising at least three pricking needles, wherein the pricking needles are used to detach the Micro LED chip from the temporary substrate and transfer it to the target substrate; A pulley, used for conveying the temporary substrate; During the transfer of the Micro LED chip, the thorn wheel and the pulley are located above the machine platform and on a side of the temporary substrate away from the Micro LED chip; The thorn wheel comprises a hub and the thorn needle, and the thorn needle is arranged on the outer periphery of the hub; The temporary substrate is a conveyor chain, and the conveyor chain includes a groove and an opening, wherein the groove is provided on a side of the conveyor chain carrying the Micro LED chip, and is used to accommodate and fix the Micro LED chip, and the opening is connected to the groove and penetrates the conveyor chain; The height H of the needle is greater than the depth L of the opening, and the diameter of the needle from the top to the root L is smaller than the diameter of the opening.

2. The transfer device according to claim 1, characterized in that The top of the needle is a flat surface or a convex curved surface.

3. The transfer device according to claim 1, characterized in that The tip diameter of the needle is less than 20 micrometers, and the height of the needle is greater than 10 micrometers.

4. The transfer device according to claim 1, characterized in that The temporary substrate is a conveyor belt, and the conveyor belt includes an adhesive layer. The adhesive layer is located on the surface of the conveyor belt carrying the Micro LED chip and is used to stick and fix the Micro LED chip.

5. The transfer device according to claim 1, characterized in that The pulley includes an active transmission wheel, and the active transmission wheel and the spur wheel transmit the temporary substrate together.

6. The transfer device according to claim 1, characterized in that The pulley comprises a driving transmission wheel and a driven transmission wheel, the driving transmission wheel and the driven transmission wheel are located on both sides of the thorn wheel, and the tip of the thorn needle protrudes from the transmission plane of the driving transmission wheel and the driven transmission wheel.

7. A method for transferring a Micro LED chip, characterized in that: The steps of the transfer method are implemented by using the transfer device according to any one of claims 1 to 6, and the transfer method comprises: Transferring the pre-arranged Micro LED chips to the temporary substrate; The temporary substrate is transferred by the pulley, and the target substrate is transferred by the machine. Meanwhile, the Micro LED chip on the temporary substrate is transferred to the target substrate by rotating the thorn wheel. The linear speeds of the pulley, the machine, and the thorn wheel are equal.

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