LED chip packaging module, display screen and manufacturing method thereof

Abstract

This application provides an LED chip packaging module, a display screen, and a method for manufacturing the same. The LED chip packaging module includes: a redistribution layer (RDL), with multiple first pads on its lower surface; a micro light-emitting diode (Micro LED) chip disposed on the upper surface of the RDL, with the electrodes of the Micro LED chip facing the upper surface of the RDL and connected to the RDL; and a micro integrated circuit (Micro IC) disposed on the upper surface of the RDL, with the electrodes of the Micro IC facing the upper surface of the RDL and connected to the RDL. The first pads are electrically connected to the Micro IC via the RDL, and the Micro IC is electrically connected to the Micro LED chip via the RDL. The first pads are used to receive external driving signals. Compared with traditional manufacturing processes, the technical solution provided in this application significantly reduces the number of pads on the LED chip packaging module, allowing for a larger size for each pad. This greatly reduces the bonding difficulty between the LED chip packaging module and the driver backplane, thus improving product yield.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to an LED chip packaging module, a display screen and a manufacturing method thereof. Background Art

[0002] Micro LED, also known as micro light emitting diode, is a self-luminous lighting device that has the potential to be applied to the next generation of display technology after liquid crystal display (LCD) and active-matrix organic light-emitting diode (AMOLED).

[0003] The core technology of Micro LED display is to combine and arrange millions to tens of millions of LED chips with a size of tens of microns to form the pixels required for the display. Since LED chips are semiconductor devices, the metal electrodes and other structures on their surface can be processed using semiconductor processes. If the LED chips are to be arranged in sequence on the driving backplane such as thin film transistor (TFT) or passive matrix (PM) circuits according to the design, mass transfer and micro-nano bonding processes are required. Different from the traditional LED packaging process that only transfers a single LED chip at a time, the mass transfer technology uses a transfer head or stamp such as a polydimethylsiloxane (PDMS) substrate to transfer tens to hundreds of thousands of LED chips at the same time, so as to achieve the output demand of transferring more than one million LED chips in a short period of time.

[0004] However, since the size of Micro LED chips is only tens of microns, the future mass production goal is to reduce the size of Micro LED chips to 5-10 microns. Therefore, the size of the micro bumps made on the Micro LED chips and the process required for the bonding process also need to be reduced to below 10 microns. This makes it very difficult to bind the Micro LED chip to the driver backplane of the display under the existing Micro LED process technology, which is not conducive to improving the production yield of display products. Summary of the invention

[0005] The embodiments of the present application provide an LED chip packaging module, a display screen, and a manufacturing method thereof, which can reduce the difficulty of binding between a micro LED chip and a driving backplane of the display screen and improve the yield of the display screen product.

[0006] To achieve the above objectives, the present application provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present application provides an LED chip packaging module, comprising:

[0008] A redistribution layer RDL, wherein a plurality of first pads are arranged on the lower surface of the RDL; a micro light-emitting diode Micro LED chip is arranged on the upper surface of the RDL, wherein the electrodes of the Micro LED chip face the RDL and are connected to the RDL; a micro integrated circuit Micro IC is arranged on the upper surface and / or lower surface of the RDL, wherein the electrodes of the Micro IC face the RDL and are connected to the RDL; wherein the first pads are electrically connected to the Micro IC through the RDL, and the Micro IC is electrically connected to the Micro LED chip through the RDL, the first pads are used to receive external driving signals, and the Micro IC is used to control the working state of the Micro LED chip electrically connected thereto according to the external driving signals. When the Micro LED chip packaging module provided in the embodiment of the present application is driven by an external driving signal, the driving signal first controls the Micro IC, and then the Micro IC controls the working state of at least one Micro LED chip connected to it according to the driving signal. In this way, the LED chip packaging module does not need to be provided with pads for connecting the electrodes of the Micro LED chip to external devices such as the driving backplane, thereby reducing the number of pads between the Micro LED chip packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0009] In one implementation, the Micro LED chips form a plurality of pixels, and each pixel includes at least one Micro LED chip. Thus, one or more Micro LED chips can flexibly form pixels with different color capabilities, such as full-color pixels, monochrome pixels, etc.

[0010] In one implementation, a Micro IC is set corresponding to each pixel, and the Micro IC is set adjacent to the corresponding pixel. The Micro IC is electrically connected to the Micro LED chip in the corresponding pixel through RDL. In this way, each Micro IC controls one pixel separately, forming a one-to-one control solution.

[0011] In one implementation, a Micro IC is set corresponding to multiple pixels, and the Micro IC is set between the corresponding multiple pixels. The Micro IC is electrically connected to the Micro LED chips in the corresponding multiple pixels through RDL. In this way, each Micro IC controls multiple pixels separately, forming a one-to-many control solution, which can reduce the number of Micro ICs.

[0012] In one implementation, when the Micro IC is located on the upper surface of the RDL, the electrodes of the Micro IC and the electrodes of the MicroLED chip are located in the same plane. In this way, it is convenient to make an RDL with a flat and smooth upper surface to improve the display performance of the LED chip packaging module.

[0013] In one implementation, the LED chip packaging module further includes: a light-isolating structure disposed on the upper surface of the RDL, the light-isolating structure being distributed between adjacent pixels, and / or the light-isolating structure being distributed between adjacent Micro LED chips. The light-isolating structure can prevent light from leaking from gaps between pixels and Micro LED chips, reduce cross-talk between pixels, increase or converge the viewing angle of light emitted by the Micro LED chip, improve light-emitting efficiency, and improve display effects.

[0014] In one implementation, the LED chip packaging module further includes: a transparent packaging layer disposed on the upper surface of the RDL, the transparent packaging layer covering the surface of the Micro LED and / or Micro IC. The transparent packaging layer can fix the positions of the Micro LED and / or Micro IC to each other and play a protective role.

[0015] In one implementation, the transparent encapsulation layer includes an encapsulation plane parallel to the upper surface of the RDL on a side away from the RDL, and the encapsulation plane is provided with a micro-nano structure. The micro-nano structure can improve the luminous efficiency of the Micro LED chip, improve the luminous field, or achieve other optical property improvement effects.

[0016] In one implementation, the LED chip packaging module further includes: a color conversion material, which is coated on the surface of part or all of the Micro LED chips and is used to convert the color light emitted by the Micro LED chips into other colors. The color conversion material can make a single-color Micro LED chip emit different colors of light, which can reduce the use of Micro LED chips of different colors when manufacturing the LED chip packaging module, or realize the light emission correction of the LED chip packaging module in the later stage.

[0017] In one implementation, a pixel includes N main Micro LED chips and N backup Micro LED chips corresponding to the N main Micro LED chips. The backup Micro LED chips are used to replace the corresponding main Micro LED chips when the corresponding main Micro LED chips fail. N is a positive integer. In this way, when any main Micro LED chip fails, the Micro IC can drive the backup Micro LED chip of the same color to replace the failed Micro LED chip, so that the pixel can still display the color normally, thereby maintaining the display integrity of the LED chip packaging module and improving the yield of the LED chip packaging module.

[0018] In one implementation, a pixel includes N main Micro LED chips and a backup Micro LED chip. The backup Micro LED chip is used to replace the failed main Micro LED chip when any of the main Micro LED chips fails, and N is a positive integer. In this way, when any of the main Micro LED chips fails, the transparent encapsulation layer around the backup Micro LED chip can be first removed by laser, and then a color conversion material with the same color as the failed Micro LED chip can be sprayed, so that the backup Micro LED chip can emit the same color light as the failed Micro LED chip after being driven by the Micro IC, so that the pixel can still display color normally and the number of backup Micro LED chips can be reduced.

[0019] In one implementation, a pixel includes N main Micro LED chips, and a spare Micro LED chip is included between two adjacent pixels. The spare Micro LED chip is used to replace the failed main Micro LED chip when any one of the main Micro LED chips in the two adjacent pixels fails, and N is a positive integer. In this way, when any one of the main Micro LED chips fails, the transparent encapsulation layer around the spare Micro LED chip can be first removed by laser, and then the color conversion material with the same color as the failed Micro LED chip can be sprayed, so that the spare Micro LED chip can emit the same color light as the failed Micro LED chip after being driven by the Micro IC, so that the pixel can still display color normally and the number of spare Micro LED chips can be reduced.

[0020] In one implementation, when the light emitted by the Micro LED chip does not pass through the RDL to the external environment, the insulating flat layer of the RDL is an opaque material. Thus, the RDL can absorb or reflect the light emitted by the Micro LED chip to increase the light output.

[0021] In one implementation, when the light emitted by the Micro LED chip passes through the RDL to the external environment, the insulating flat layer of the RDL is a transparent material, so that the light emitted by the Micro LED chip can efficiently pass through the RDL to increase the light output.

[0022] In a second aspect, the present application provides another LED chip packaging module, including:

[0023] A redistribution layer RDL, wherein the lower surface of the RDL is provided with a plurality of first pads; a micro-light-emitting diode Micro LED chip is provided on the upper surface of the RDL, wherein the electrode of the Micro LED chip faces the RDL and is connected to the RDL; wherein the first pad is electrically connected to the Micro LED chip through the RDL, and the first pad is used to receive an external driving signal, and the external driving signal is used to control the working state of the Micro LED chip. When the Micro LED chip packaging module provided in the embodiment of the present application is driven by an external driving signal, the driving signal is directly sent to at least one Micro LED chip through the pad and the RDL, so that one driving signal controls one or more Micro LED chips. In this way, the LED chip packaging module does not need to be provided with pads for directly connecting the electrodes of the Micro LED chip to external devices such as a driving backplane, thereby reducing the number of pads between the Micro LED chip packaging module and external devices such as a driving backplane, so that under the same size of the LED chip packaging module and the driving backplane, the size of each pad can be larger, thereby greatly reducing the difficulty of bonding between the LED chip packaging module and the driving backplane, which is conducive to improving the product yield.

[0024] In one implementation, the Micro LED chips form a plurality of pixels, and each pixel includes at least one Micro LED chip. Thus, one or more Micro LED chips can flexibly form pixels with different color capabilities, such as full-color pixels, monochrome pixels, etc.

[0025] In one implementation, each first pad is electrically connected to the Micro LED chip of at least one pixel through the RDL. Thus, an external driving signal can be sent to the Micro LED chips in one or more pixels through the first pad and the RDL to control the display state of one or more pixels.

[0026] In one implementation, the LED chip packaging module further includes: a light-isolating structure disposed on the upper surface of the RDL, the light-isolating structure being distributed between adjacent pixels, and / or the light-isolating structure being distributed between adjacent Micro LED chips. The light-isolating structure can prevent light from leaking from gaps between pixels and Micro LED chips, reduce cross-talk between pixels, increase or converge the viewing angle of light emitted by the Micro LED chip, improve light-emitting efficiency, and improve display effects.

[0027] In one implementation, the LED chip packaging module further includes: a transparent packaging layer disposed on the upper surface of the RDL, the transparent packaging layer covering the surface of the Micro LED chip. The transparent packaging layer can fix the positions of the Micro LED and / or Micro IC to each other and play a protective role.

[0028] In one implementation, the transparent encapsulation layer includes an encapsulation plane parallel to the upper surface of the RDL on a side away from the RDL, and the encapsulation plane is provided with a micro-nano structure. The micro-nano structure can improve the luminous efficiency of the Micro LED chip, improve the luminous field, or achieve other optical property improvement effects.

[0029] In a third aspect, an embodiment of the present application provides a method for packaging an LED chip, comprising:

[0030] The Micro LED chip and the Micro IC are arranged separably on the first substrate, and the electrodes of the Micro LED chip and the electrodes of the Micro IC are placed facing the first substrate; a transparent encapsulation layer is coated on the surface of the Micro LED chip, the Micro IC and the first substrate; after the transparent encapsulation layer is cured, the first substrate is removed so that the transparent encapsulation layer forms a first plane exposing the electrodes of the Micro LED chip and the electrodes of the Micro IC; an RDL is made on the first plane, and the Micro IC is electrically connected to the MicroLED through the RDL; a first pad is made on the lower surface of the RDL opposite to the transparent encapsulation layer, and the first pad is electrically connected to the Micro IC through the RDL, and the first pad is used to receive an external driving signal, and the Micro IC is used to control the working state of the Micro LED chip electrically connected to it according to the external driving signal. When the MicroLED chip packaging module manufactured by the method provided in the embodiment of the present application is driven by an external driving signal, the driving signal first controls the Micro IC, and then the Micro IC controls the working state of at least one Micro LED chip connected to it according to the driving signal. In this way, the LED chip packaging module does not need to be provided with pads for connecting the electrodes of the Micro LED chip to external devices such as the driving backplane, thereby reducing the number of pads between the Micro LED chip packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0031] In one implementation, the Micro LED chip and the Micro IC are arranged on the first substrate in a separable manner, including: arranging a plurality of Micro LED chips on the first substrate to form a plurality of pixels, each pixel including at least one Micro LED chip, and a Micro IC is disposed adjacent to one side of each pixel. Thus, one or more Micro LED chips can be flexibly formed into pixels with different color capabilities, such as full-color pixels, monochrome pixels, etc., and the pixels and Micro ICs are configured one-to-one.

[0032] In one implementation, RDL electrically connects the Micro LED chip in each pixel to its adjacent Micro IC. Thus, each Micro IC controls one pixel individually, forming a one-to-one control solution.

[0033] In one implementation, the Micro LED chip and the Micro IC are arranged on the first substrate in a separable manner, including: arranging a plurality of Micro LED chips on the first substrate to form a plurality of pixels, each pixel including at least one Micro LED chip, and distributing at least one Micro IC between the plurality of pixels. Thus, one or more Micro LED chips can flexibly form pixels with different color capabilities, such as full-color pixels, monochrome pixels, etc., and the pixels and the Micro ICs realize a one-to-many configuration.

[0034] In one implementation, the RDL electrically connects each Micro IC to the Micro LED chip in at least one pixel. In this way, each Micro IC controls multiple pixels individually, forming a one-to-many control solution, which can reduce the number of Micro ICs.

[0035] In one implementation, before the transparent encapsulation layer is coated on the surface of the Micro LED chip, the Micro IC and the first substrate, it also includes: making a light isolation structure on the surface of the first substrate, and the light isolation structure can be set between adjacent pixels or between adjacent Micro LED chips. The light isolation structure can prevent light from leaking from the gaps between pixels and Micro LED chips, reduce cross-talk between pixels, increase or converge the visual angle of the light emitted by the Micro LED chip, improve the light emission efficiency, and improve the display effect.

[0036] In one implementation, before the transparent encapsulation layer is coated on the surface of the Micro LED chip, the Micro IC and the first substrate, the process further includes: coating a color conversion material on the surface of part or all of the Micro LED chips, the color conversion material being used to convert the color light emitted by the Micro LED chip into other colors. The color conversion material can make a single-color Micro LED chip emit different colors of light, which can reduce the use of Micro LED chips of different colors when manufacturing an LED chip packaging module, or realize the light emission correction of the LED chip packaging module in the later stage.

[0037] In one implementation, after a transparent encapsulation layer is coated on the surface of the Micro LED chip, the Micro IC and the first substrate, the process further includes: polishing the side of the transparent encapsulation layer away from the first substrate to form an encapsulation plane parallel to the first substrate; and making a micro-nano structure on the encapsulation plane. The micro-nano structure can improve the luminous efficiency of the Micro LED chip, improve the luminous field pattern, or achieve other optical property improvement effects.

[0038] In one implementation, a first adhesive layer is disposed on the surface of the first substrate, and the first adhesive layer is used to detachably place the Micro LED chip and the Micro IC. In this way, the Micro LED chip and the Micro IC can be temporarily fixed on the first substrate by using the first adhesive layer.

[0039] In one implementation, before arranging the Micro LED chip and the Micro IC on the first substrate in a separable manner, the process further includes: growing a Micro LED epitaxial wafer structure on the surface of the substrate; using a standard semiconductor process to manufacture the epitaxial wafer structure into a plurality of Micro LED chips; flipping the substrate and the Micro LED chips thereon as a whole and placing them on the second substrate in a separable manner; and removing the substrate. In this way, a plurality of Micro LED chips independently arranged from each other can be obtained at one time.

[0040] In one implementation, a second adhesive layer is disposed on the surface of the second substrate, and the second adhesive layer is used to detachably place the Micro LED chip. In this way, the Micro LED chip can be temporarily fixed on the second substrate by using the first adhesive layer.

[0041] In one implementation, the Micro LED chips and Micro ICs are arranged on the first substrate in a detachable manner, including: gluing a plurality of Micro LED chips from the second substrate at one time, placing the gluing Micro LED chips on the first substrate, and gluing at least one Micro IC from the third substrate on which the Micro ICs are detachably placed at one time, and placing the gluing Micro ICs on the first substrate. Thus, the mass transfer of Micro LED chips and Micro ICs is achieved, and the manufacturing efficiency of LED chip packaging modules is improved.

[0042] In a fourth aspect, an embodiment of the present application provides another LED chip packaging method, comprising:

[0043] The Micro LED chips are arranged on the first substrate in a separable manner, and the electrode surface of the Micro LED chip is placed toward the first substrate; a transparent encapsulation layer is coated on the surface of the Micro LED chip and the first substrate; after the transparent encapsulation layer is cured, the first substrate is removed so that the transparent encapsulation layer forms a first plane exposing the electrode of the Micro LED chip; an RDL is made on the first plane, and a Micro IC is installed on the lower surface of the RDL facing away from the transparent encapsulation layer, the electrode surface of the Micro IC is arranged toward the RDL, and the Micro IC is electrically connected to the Micro LED through the RDL; a first soldering pad is made on the lower surface of the RDL, the first soldering pad is electrically connected to the Micro IC through the RDL, the first soldering pad is used to receive an external driving signal, and the Micro IC is used to control the working state of the Micro LED chip electrically connected thereto according to the external driving signal. When the Micro LED chip packaging module manufactured by the method provided in the embodiment of the present application is driven by an external driving signal, the driving signal first controls the Micro IC, and then the Micro IC controls the working state of at least one Micro LED chip connected to it according to the driving signal. In this way, the LED chip packaging module does not need to be provided with pads for connecting the electrodes of the Micro LED chip to external devices such as the driving backplane, thereby reducing the number of pads between the Micro LED chip packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0044] In one implementation, a plurality of Micro LED chips are arranged on a first substrate to form a plurality of pixels, and each pixel includes at least one Micro LED chip. Thus, one or more Micro LED chips can flexibly form pixels with different color capabilities, such as full-color pixels, monochrome pixels, etc.

[0045] In one implementation, the RDL electrically connects each Micro IC to the Micro LED chip in at least one pixel. Thus, each Micro IC controls one pixel individually, forming a one-to-one control solution, and each Micro IC controls multiple pixels individually, forming a one-to-many control solution, thereby reducing the number of Micro ICs.

[0046] In one implementation, a transparent encapsulation layer is coated on the surface of the Micro LED chip and the first substrate, and further includes: making a light-isolating structure on the surface of the first substrate, and the light-isolating structure can be set between adjacent pixels or between adjacent Micro LED chips. The light-isolating structure can prevent light from leaking from gaps between pixels and Micro LED chips, reduce cross-talk between pixels, increase or converge the visual angle of light emitted by the Micro LED chip, improve light-emitting efficiency, and improve display effects.

[0047] In one implementation, after the transparent encapsulation layer is coated on the surface of the Micro LED chip and the first substrate, the method further includes: polishing the side of the transparent encapsulation layer away from the first substrate to form an encapsulation plane parallel to the first substrate; and making a micro-nano structure on the encapsulation plane. The micro-nano structure can improve the luminous efficiency of the Micro LED chip, improve the luminous field pattern, or achieve other optical property improvement effects.

[0048] In a fifth aspect, the present application provides another LED chip packaging method, comprising:

[0049] The Micro LED chips are arranged separably on the first substrate, with the electrodes of the Micro LED chips facing the first substrate; a transparent encapsulation layer is coated on the surfaces of the Micro LED chips and the first substrate; after the transparent encapsulation layer is cured, the first substrate is removed so that the transparent encapsulation layer forms a first plane exposing the electrodes of the Micro LED chips; an RDL is made on the first plane, and a first pad is made on the lower surface of the RDL opposite to the transparent encapsulation layer, the first pad is electrically connected to the Micro LED chip through the RDL, and the first pad is used to receive an external driving signal, and the external driving signal is used to control the working state of the Micro LED chip electrically connected thereto. When the Micro LED chip packaging module manufactured according to the method provided in the embodiment of the present application is driven by an external driving signal, the driving signal is directly sent to at least one Micro LED chip through the pad and RDL, so that one driving signal controls one or more Micro LED chips. In this way, the LED chip packaging module does not need to be provided with pads for directly connecting the electrodes of the Micro LED chip to external devices such as the driving backplane, thereby reducing the number of pads between the Micro LED chip packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0050] In one implementation, a plurality of Micro LED chips are arranged on a first substrate to form a plurality of pixels, and each pixel includes at least one Micro LED chip. Thus, one or more Micro LED chips can flexibly form pixels with different color capabilities, such as full-color pixels, monochrome pixels, etc.

[0051] In one implementation, a transparent encapsulation layer is coated on the surface of the Micro LED chip and the first substrate, and further includes: making a light isolation structure on the surface of the first substrate, and the light isolation structure can be set between adjacent pixels, and the light isolation structure can also be set between adjacent Micro LED chips. The light isolation structure can prevent light from leaking from the gaps between pixels and Micro LED chips, reduce cross-talk between pixels, increase or converge the visual angle of the light emitted by the Micro LED chip, improve the light emission efficiency, and improve the display effect.

[0052] In one implementation, after the transparent encapsulation layer is coated on the surface of the Micro LED chip and the first substrate, the method further includes: polishing the side of the transparent encapsulation layer away from the first substrate to form an encapsulation plane parallel to the first substrate; and making a micro-nano structure on the encapsulation plane. The micro-nano structure can improve the luminous efficiency of the Micro LED chip, improve the luminous field pattern, or achieve other optical property improvement effects.

[0053] In a sixth aspect, an embodiment of the present application provides a display screen, comprising: a driving backplane, a display driver integrated circuit DDIC for generating an external driving signal, and at least one LED chip packaging module as provided in the aforementioned first aspect, second aspect, and any implementation thereof; the DDIC and at least one LED chip packaging module are arranged on the driving backplane; the driving backplane comprises a second pad corresponding to the position of the first pad of at least one LED chip packaging module, and the second pad is connected to the DDIC through a line; the first pad is used for the LED chip packaging module to receive an external driving signal, and the first pad is welded to the second pad. Since the number of first pads of the LED chip packaging module provided in the embodiment of the present application is less, the number of second pads correspondingly arranged on the driving backplane can also be less, so the welding difficulty between the LED chip packaging module and the driving backplane is lower, which is conducive to improving the yield of the display screen.

[0054] In a seventh aspect, an embodiment of the present application provides an electronic device, comprising the display screen provided in the sixth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is a schematic diagram of the current Micro LED mass transfer and micro-nano binding process;

[0056] Figure 2is a schematic diagram of the current optical structure between pixels;

[0057] Figure 3 is a flow chart of a method for packaging an LED chip provided in an embodiment of the present application;

[0058] Figure 4 It is a schematic diagram of the structure formed by various steps of the LED chip packaging method provided in the embodiment of the present application;

[0059] Figure 5 This is a full-color pixel diagram of a micro LED display;

[0060] Figure 6 This is a schematic diagram of the arrangement of Micro LED chips and Micro ICs;

[0061] Figure 7 This is a schematic diagram of the arrangement of Micro LED chips and Micro ICs;

[0062] Figure 8 It is a schematic diagram of a light-isolating structure produced by a packaging method for an LED chip provided in an embodiment of the present application;

[0063] Fig. 9 It is a schematic diagram of the LED chip packaging method provided in the embodiment of the present application for making a color conversion material;

[0064] Fig.10 It is a schematic diagram of the LED chip packaging method provided in the embodiment of the present application for manufacturing a light-isolating structure and a color conversion material;

[0065] Fig.11 It is a schematic diagram of manufacturing a micro-nano structure by a packaging method of an LED chip provided in an embodiment of the present application;

[0066] Fig.12 is a structural schematic diagram of an LED chip packaging module according to an embodiment of the present application;

[0067] Fig.13 Schematic diagram of the arrangement of Micro LED chips and Micro ICs in the LED chip packaging module of an embodiment of the present application;

[0068] Fig.14 Schematic diagram of the arrangement of Micro LED chips and Micro ICs in the LED chip packaging module of an embodiment of the present application;

[0069] Fig.15 Schematic diagram of the arrangement of Micro LED chips and Micro ICs in the LED chip packaging module of an embodiment of the present application;

[0070] Fig.16is another structural schematic diagram of the LED chip packaging module of the embodiment of the present application;

[0071] Fig.17 Schematic diagram of the arrangement of the main and backup Micro LED chips of the LED chip packaging module of the embodiment of the present application;

[0072] Fig.18 Schematic diagram of the arrangement of the main and backup Micro LED chips of the LED chip packaging module of the embodiment of the present application;

[0073] Fig.19 Schematic diagram of the arrangement of the main and backup Micro LED chips of the LED chip packaging module of the embodiment of the present application;

[0074] Fig. 20 Schematic diagram of the arrangement of the main and backup Micro LED chips of the LED chip packaging module of the embodiment of the present application;

[0075] Fig.21 is a flow chart of another LED chip packaging method provided in an embodiment of the present application;

[0076] Fig. 22 This is a schematic diagram of the arrangement of Micro LED chips and Micro ICs;

[0077] Fig.23 is another structural schematic diagram of the LED chip packaging module of the embodiment of the present application;

[0078] Fig.24 is a flow chart of another LED chip packaging method provided in an embodiment of the present application;

[0079] Fig.25 is another structural schematic diagram of the LED chip packaging module of the embodiment of the present application;

[0080] Fig.26 This is an example diagram of the pads and RDL lines of the LED chip packaging module;

[0081] Fig. 27 It is a structural schematic diagram of a display screen provided in an application embodiment;

[0082] Fig.28 It is a schematic diagram of the splicing of LED chip packaging modules of a display screen provided in an embodiment of the application. DETAILED DESCRIPTION

[0083] In order to facilitate understanding of the technical solution of the embodiment of the present application, before describing the specific implementation of the embodiment of the present application, some technical terms in the technical field to which the embodiment of the present application belongs are briefly explained. Among them:

[0084] Gallium nitride (GaN) refers to a compound of nitrogen and gallium. It is a direct bandgap semiconductor of group III and group V and is commonly used in light-emitting diodes.

[0085] Metal-organic chemical vapor deposition (MOCVD) is a method for growing semiconductor thin films on substrates. Other similar names for this method include MOVPE (metal-organic vapor-phase epitaxy), OMVPE (organometallic vapor-phase epitaxy) and OMCVD (organometallic chemical vapor deposition). "MO" or "OM" refers to the fact that the precusor used in the growth of semiconductor thin films is a metal compound "metal-organic" or an organometallic compound; and the last three letters "CVD" or "VPE" refer to the characteristics of the grown semiconductor thin film, which is an amorphous film or a crystalline film.

[0086] A re-distribution layer (RDL) is an additional metal layer on a chip that allows the electrodes or input / output pads (I / O pads) of the chip to be rearranged to other locations on the chip to facilitate connection with other integrated circuits or chips, or to connect electrodes or I / O pads of different chips together.

[0087] A display driver integrated circuit (DDIC) generally includes a microcontroller, a microprocessor and a peripheral device interface, and is used to generate appropriate voltage, current and timing signals to drive the pixels of the display screen so that the display screen produces corresponding images.

[0088] Surface-mount technology (SMT) is an electronic assembly technology that mounts electronic components, such as resistors, capacitors, transistors, integrated circuits, etc., on printed circuit boards and forms electrical connections through soldering, so there is no need to reserve corresponding through holes for the pins of the components. The components used are also referred to as surface-mount devices (SMD).

[0089] Crosstalk, also known as crosstalk interference, refers to the coupling phenomenon between two signal lines in electronics. The cause is that signal lines that are close to each other will have unwanted inductive and capacitive coupling, which will interfere with each other. Among them, capacitive coupling will cause coupling current, while inductive coupling will cause coupling voltage.

[0090] Epitaxy, also known as epitaxial growth, is a technology used in the semiconductor device manufacturing process to grow new crystals on the original chip to make a new semiconductor layer. The crystals or grains grown by epitaxy technology can also be called epitaxy, or epitaxial layer, epitaxial wafer.

[0091] Micro-nano structure refers to an artificially designed functional structure with micron or nanometer-scale characteristic dimensions and arranged in a specific way.

[0092] Micro LED, also known as micro light emitting diode, is a self-luminous lighting device that has the potential to be applied to the next generation of display technology after liquid crystal display (LCD) and active-matrix organic light-emitting diode (AMOLED). The core technology of Micro LED display is to combine and arrange millions to tens of millions of LED chips with a size of tens of microns to form the pixels required for the display. Therefore, its process is very different from the combination of LED through the liquid crystal layer and the backlight layer, and the AMOLED process of using organic material evaporation.

[0093] Since LED chips are semiconductor devices, the metal electrodes and other structures on their surfaces can be processed using semiconductor processes. If the LED chips are to be arranged in order on a driving backplane such as a thin film transistor (TFT) or passive matrix (PM) circuit, mass transfer and micro-nano bonding processes must be used to transfer and fix the LED chips on the driving backplane. Unlike the traditional LED packaging process that only transfers a single LED chip at a time, mass transfer technology uses a transfer head or stamp such as a polydimethylsiloxane (PDMS) substrate to transfer tens to hundreds of thousands of LED chips at the same time, so as to achieve the output demand of transferring more than one million LED chips in a short period of time. However, since the size of Micro LED chips is only tens of microns, the future mass production goal is to reduce the size of Micro LED chips to 5-10 microns. Therefore, the size of the micro bumps made on the Micro LED chips and the process required for the bonding process also need to be reduced to less than 10 microns, making it difficult for existing Micro LED process technology to meet such process requirements.

[0094] The following is a brief description of the current Micro LED mass transfer and micro-nano binding processes in conjunction with some drawings, so that those skilled in the art can understand the technical scenarios of the embodiments of the present application and the deficiencies of the mass transfer and micro-nano binding processes in Micro LED applications.

[0095] Figure 1 This is a schematic diagram of the current Micro LED mass transfer and micro-nano bonding process. Figure 1As shown, taking a Micro LED chip made of GaN / InGaN material (e.g., a blue or green Micro LED chip) as an example, to obtain a Micro LED chip structure, first, an LED epitaxial wafer structure (LED epi-ayers) 020 can be grown on the surface of a substrate 010 made of, for example, sapphire (sub) material; then, the epitaxial wafer structure 020 is made into a large number of Micro LED chips 030 with a size of about 10 microns using a standard semiconductor process, wherein the surface of the Micro LED chip 030 includes, in addition to an ohmic electrode 040 made to reduce the current flowing into the semiconductor (the ohmic electrode 040 includes the P / N electrode of the LED chip), a micro bump 050 prepared for a subsequent bonding process is also required, and the micro bump 050 is prepared on the ohmic electrode 040. In order to reduce the temperature required for the bonding process, the micro bump metal used here can be a low-temperature bonding metal alloy including indium In, tin Sn, copper Au, etc.; after the chip process is completed, the substrate 010 and the epitaxial wafer structure 020 thereon can be turned over as a whole and pasted to a substrate carrier. 1, the substrate carrier 1 can be made of glass or other materials, and has an adhesive layer 061 on its surface. The adhesive layer 061 contacts the micro bump 050 and can temporarily fix the epitaxial wafer structure 020 without damaging the device structure. Next, in order to remove the sapphire substrate 010, the epitaxial wafer structure 020 can be irradiated from the sapphire substrate 010 side with a laser. The laser wavelength will not be absorbed by the sapphire substrate 010, but it will react with the GaN material to separate the epitaxial wafer structure 020 from the sapphire substrate 010 at the interface.

[0096] After the epitaxial wafer structure 020 is separated from the sapphire substrate 010, the Micro LED chips 030 are respectively and independently bonded onto the substrate carrier 1. At this time, a patterned transfer head (stamp) can be used to selectively pick or suck the required Micro LED chips 030 from the substrate carrier 1. This stamp can be made of PDMS material using van der waals force. In addition, other mechanisms such as electrostatic force and magnetic force can also be used to suck the Micro LED chips 030; after using the stamp to pick the Micro LED chips 030, the Micro LED chips 030 can be transferred to another substrate carrier 2. The surface of the substrate carrier 2 also has an adhesive layer 062 or an adhesion device, which can temporarily fix the Micro LED chips 030. Generally speaking, in order for the PDMS stamp to successfully pick the Micro LED chips 030 from the substrate carrier 1 and temporarily fix the Micro LED chips 030 onto the substrate carrier 2, the adhesive force should satisfy: adhesive layer 061 < PDMS < adhesive layer 062. Therefore, the adhesive layer 061 and the adhesive layer 062 can be made of different materials. Using the stamp to transfer the Micro LED chips 030 from the substrate carrier 1 to the substrate carrier 2 has the following multiple purposes, including: adjusting the pitch of the Micro LED chips 030, forming a full-color arrangement (such as red, green, blue RGB arrangement) of the Micro LED chips 030 on the surface of the substrate carrier 2, or performing a double-sided process for other chips, etc.

[0097] After the Micro LED chips 030 are arranged on the surface of the substrate carrier 2, another stamp can be used to pick all the Micro LED chips 030 at one time and transfer them to the corresponding area of the driving backplane 070; then, the positive and negative electrodes on the surface of the Micro LED chips 030 are mechanically and electrically connected to the corresponding electrodes 080 on the driving backplane using the microbump 050. Generally, the following technological processes are involved here, including: alignment of the positive and negative electrodes on the surface of the Micro LED chips 030 with the corresponding electrodes 080 on the driving backplane, pressing down the Micro LED chips 030, heating to soften the solder material of the micro bump 050 so that the positive and negative electrodes on the surface of the Micro LED chips 030 form a eutectic bond with the corresponding electrodes 080 on the driving backplane, and cooling down, etc.

[0098] It can be understood that by using Figure 1Although the micro bump and bonding process shown in the figure can realize the electrical connection between the positive and negative electrodes on the surface of the Micro LED chip and the corresponding electrodes on the driving backplane, the size of the Micro LED chip is developing in the direction of continuous miniaturization. When the size of the Micro LED chip is reduced to a certain extent, such as 10 to 15 microns and below, Figure 1 The micro bump and bonding process shown above have difficult to overcome problems in terms of process implementation and production yield. Specifically, they can be manifested as:

[0099] 1. Micro bumps generally contain solder materials such as indium In or tin Sn, which can help reduce the bonding temperature, but these materials are also prone to diffusion in the alloy. In order to prevent the solder material from diffusing into the ohmic metal layer and thus affecting the device characteristics and yield, it is usually necessary to thicken the thickness of the gold Au or other metal layer in the micro bump, which is not conducive to the miniaturization of the Micro LED chip. In addition, when the Micro LED chip and the driver backplane are connected by the bonding process, the chip and the driver backplane are mechanically and electrically connected through the micro bump, but the changes in process parameters such as the contact state of the stamp and the chip in the bonding process, the uniformity of pressure and temperature, and the cooling process may cause the distance, angle, and direction of the connection between the chip and the backplane to change, resulting in slight differences in the field pattern emitted by each Micro LED chip, and users will feel that the pixels are messy when observing the display.

[0100] 2. Micro LED chips cannot be tested before all processes are completed. Since Micro LED chips can only be powered on and tested for characteristics analysis after being connected to the driver backplane, Figure 1After all the processes are completed, if it is found through testing that the Micro LED chip fails due to problems with the Micro LED chip itself or the process, a defect-free Micro LED display can only be obtained through the rework process. However, the rework process involves the removal of the failed Micro LED chip, the cleaning and resetting of the pads, and the transfer and bonding of a single Micro LED chip. It is not only technically difficult to achieve, but also the unit man-hours consumed on each pixel are far greater than the man-hours of the massive transfer, making it difficult to implement in a production environment. In addition, if the rework process is to be avoided, one possible way is to use backup chips (redundancy). In short, the redundancy method is to place twice as many backup Micro LED chips on the Micro LED display. When the original Micro LED chip fails and cannot be operated, the backup chip is activated to replace the original Micro LED chip to maintain full-screen illumination. Obviously, this method will increase the production cost of the display and reduce the resolution of the display.

[0101] 3. It is difficult to manufacture optical or other components between Micro LED chips in a volumetric process. Figure 2 As shown in the figure, in addition to the thickness of the Micro LED chip, each pixel on the MicroLED display needs to be superimposed with the thickness of the micro bump to form the total thickness of the pixel. Generally speaking, in order to improve the fault tolerance and yield of the bonding process, the thickness H1 of the micro bump may reach 5 to 8 microns. If the thickness of the Micro LED chip is added, the total thickness H2 of each pixel may reach 10 to 15 microns or even higher. In this case, the aspect ratio between the total thickness H2 of the pixel and the distance B1 between pixels will be relatively high. At this time, if an optical structure 090 is to be made between pixels, such as changing the light type or reducing the cross-talk, then the excessively high aspect ratio will lead to a decrease in the precision and yield of semiconductor processes such as photolithography between pixels, and will also have a negative impact on the volumetric goals of other sensing devices.

[0102] To solve the above technical problems, the present application provides a method for packaging LED chips. The method can be applied to the packaging of various LED chips, such as packaging Micro LED chips or Mini LED chips on substrates such as TFT to produce Micro LED or Mini LED chip packaging modules or display screens.

[0103] The following takes the packaging of Micro LED chips to produce a Micro LED chip packaging module as an example to specifically illustrate the method provided in the embodiment of the present application. It can be understood that the following method steps are also applicable to the packaging process of Mini LED chips or other LED chips.

[0104] Figure 3 and Figure 4 They are respectively a flow chart of the LED chip packaging method provided in the embodiment of the present application and a structural schematic diagram formed by each step.

[0105] like Figure 3 and Figure 4 As shown, the method may include the following steps:

[0106] Step S101 , growing a micro LED epitaxial wafer structure 120 on a surface of a substrate 110 .

[0107] The material of the substrate 110 that can be used as the epitaxial wafer structure 120 may include, for example, sapphire, aluminum nitride AlN, silicon carbide SiC, GaN single crystal material and other materials, which are not limited in the present application.

[0108] In a specific implementation, the epitaxial material used to grow the epitaxial wafer structure 120 can be determined according to the luminous color of the micro LED chip to be prepared. For example, if a micro LED chip emitting blue light or green light is to be prepared, GaN / InGaN material can be used to grow the epitaxial wafer structure 120; for another example, if a micro LED chip emitting red light is to be prepared, GaAsP and other materials can be used to grow the epitaxial wafer structure 120. Other materials that can be used to grow the epitaxial wafer structure 120 may also include SiC, AlGaP, etc., which will not be further described here due to limited space.

[0109] It is necessary to add that, Figure 5As shown, in the micro LED display screen 100, each full-color pixel can be composed of multiple micro LED chips. Taking the most basic pixel structure as an example, it can include a micro LED chip R whose own epitaxial material emits red light, a micro LED chip G whose own epitaxial material emits green light, and a micro LED chip B whose own epitaxial material emits blue light. It can be seen that in order to obtain the micro LED chips required for full-color pixels, in actual production, it may be necessary to use different epitaxial materials to grow epitaxial wafer structures 120 that can emit different colors of light on different substrates 110, for example, using GaN / InGaN to grow an epitaxial wafer structure 120 that can emit blue light on one substrate 110, and using GaN / InGaN to grow an epitaxial wafer structure 120 that can emit green light on another substrate 110, etc.

[0110] In step S102 , a standard semiconductor manufacturing process is used to manufacture the epitaxial wafer structure into a plurality of Micro LED chips.

[0111] In a specific implementation, the excess portion of the epitaxial wafer structure 120 can be removed by etching or other material removal techniques, so that the remaining epitaxial wafer structure 120 forms a plurality of independent structures with a size of approximately 10 microns and arranged at intervals on the substrate 110, and then an ohmic electrode (hereinafter referred to as the electrode) 140 that can reduce the current flowing into the semiconductor is made on the side of each independent structure away from the substrate, so that a complete Micro LED chip 130 can be formed, and each independent structure will eventually constitute a Micro LED chip 130.

[0112] With the adoption Figure 1 Compared with the Micro LED chip packaging structure of the micro bump and welding process shown, the Micro LED chip 130 manufactured in the embodiment of the present application does not need to be manufactured with a micro bump except for the electrode 140, thereby reducing the height of the Micro LED chip.

[0113] It should be noted that the above-mentioned size of "10 microns" is only an example size and does not constitute a specific limitation on the size of micro LED chips. Generally speaking, the size of micro LED chips can be between 1 and 60 μm. Those skilled in the art can determine the corresponding semiconductor process based on the common size range of micro LED chips, and this application does not limit this.

[0114] In step S103 , the substrate 110 and the Micro LED chip 130 thereon are turned over as a whole and detachably placed on the second substrate 150 .

[0115] The second substrate 150 can be made of glass or silicon wafer, and a second adhesive layer 160 is disposed on its surface. After the substrate 110 and the Micro LED chip 130 thereon are turned over as a whole, the substrate 110 and the Micro LED chip 130 thereon can be moved above the second substrate 150 so that the second adhesive layer 160 faces the end of the Micro LED chip 130 with the electrode 140; next, the substrate 110 and the Micro LED chip 130 thereon are moved downward so that the electrode 140 of the Micro LED chip 130 contacts the second adhesive layer 160 and adheres to the second substrate 150. The second adhesive layer 160 does not permanently fix the Micro LED chip 130 to the second substrate 150, but is only used to temporarily detachably fix the Micro LED chip 130 without destroying the device structure of the Micro LED chip 130, so that the Micro LED chip 130 can be separated from the second substrate 150 when needed.

[0116] Step S104, removing the substrate.

[0117] In a specific implementation, a laser can be used to irradiate the epitaxial wafer structure of the Micro LED chip 130 from the substrate 110 side. The wavelength of the laser allows it to pass through the substrate 110 without being absorbed by the substrate 110, but it will react with the GaN material of the epitaxial wafer structure, so that the epitaxial wafer structure of the Micro LED chip 130 and the substrate 110 are separated from the interface, thereby removing the substrate 110.

[0118] In addition, those skilled in the art may also use other semiconductor process technologies to separate the substrate 110 from the Micro LED chip 130, and this application does not limit this.

[0119] In step S105 , the Micro LED chip 130 and the Micro IC 180 are separably arranged on the first substrate 170 , wherein the electrodes 140 of the Micro LED chip 130 and the electrodes 230 of the Micro IC 180 are placed facing the first substrate 170 .

[0120] In one embodiment, a plurality of Micro LED chips 130 and the Micro IC 180 may be arranged into a plurality of pixels on the first substrate 170 , and each pixel includes at least one Micro LED chip 130 and one Micro IC 180 .

[0121] For example, Figure 6As shown in the arrangement a of FIG, a pixel includes a Micro LED chip B that emits blue light, a Micro LED chip G that emits green light, and a Micro LED chip R that emits red light. These three Micro LED chips are arranged in a row to form a standard RGB arrangement. Each pixel includes a Micro IC 180, and the Micro IC 180 and the Micro LED chip are arranged in parallel in the same row.

[0122] For example, Figure 6 As shown in the b arrangement, the pixel contains a Micro LED chip B that emits blue light, a Micro LED chip G that emits green light, and a Micro LED chip R that emits red light. The three Micro LED chips are arranged in a row to form a standard RGB arrangement. Each pixel contains a Micro IC 180, and the Micro IC 180 is arranged above or below the three Micro LED chips.

[0123] For example, Figure 6 As shown in the c arrangement, a pixel may include four Micro LED chips, such as two Micro LED chips B emitting blue light, one Micro LED chip R emitting red light, and one Micro LED chip G emitting green light. These four Micro LED chips form a rectangular arrangement. The position of each Micro LED chip can be regarded as a corner point of the rectangle. The two Micro LED chips B emitting blue light are arranged diagonally. Each pixel includes a Micro IC 180, and MicroIC 180 can be set on one side of the four Micro LED chips.

[0124] In another embodiment, a plurality of Micro LED chips 130 may be arranged into a plurality of pixels on the first substrate 170 , each pixel including at least one Micro LED chip 130 , and at least one Micro IC 180 distributed between the pixels.

[0125] For example, Figure 7 As shown in the d arrangement, the pixel contains a Micro LED chip B that emits blue light, a Micro LED chip G that emits green light, and a Micro LED chip R that emits red light. The three Micro LED chips are arranged in a row to form a standard RGB arrangement. In each row or column of pixels, a Micro IC 180 is set every a certain number N (N is a positive integer greater than 1) of pixels, and each Micro IC 180 can control N pixels.

[0126] For example, Figure 7 As shown in the e arrangement, the pixel contains a Micro LED chip B that emits blue light, a Micro LED chip G that emits green light, and a Micro LED chip R that emits red light. These three Micro LED chips are arranged in a row to form a standard RGB arrangement. In the pixels of each square area, a Micro IC 180 is set for every a certain number N (N is a positive integer greater than 1) of pixels, and each Micro IC 180 can control N pixels in the area.

[0127] To achieve the above arrangement, multiple second substrates 150 can be prepared in advance, and each second substrate 150 can be detachably placed on a Micro LED chip 130 of a color light. Then, in step S105, Micro LED chips 130 of different colors of light can be respectively sucked from different second substrates 150 and placed on the first substrate 170, and at least one Micro IC 180 can be sucked from the third substrate on which Micro IC 180 is placed and placed on the first substrate 170 at one time. The third substrate is also provided with an adhesive layer, and Micro IC 180 can be detachably placed. The above-mentioned action of sucking and placing Micro LED chips 130 and Micro IC 180 can be repeated once or multiple times, and one or more chips can be sucked each time, so that multiple Micro LED chips and at least one Micro IC 180 form a preset pixel arrangement on the first substrate 170.

[0128] The first substrate 170 can be made of glass or silicon wafer, and a first adhesive layer 190 is disposed on the surface thereof, which can temporarily fix the Micro LED chip 130 and the Micro IC 180 detachably without damaging the device structure of the Micro LED chip 130 and the Micro IC 180. When the devices of the Micro LED chip and the Micro IC 180 are detachably placed on the first substrate 170, the Micro LED chip 130 and the Micro IC 180 are in contact with the first adhesive layer 190 of the first substrate 170 at their electrode ends.

[0129] Step S106 , coating a transparent encapsulation layer 210 on the surfaces of the Micro LED chip 130 , the Micro IC 180 and the first substrate 170 .

[0130] The transparent encapsulation layer 210 may include, for example, epoxy resin and silicone resin materials. The transparent encapsulation layer 210 needs to be cured for a certain period of time after coating, and after curing, the relative positions of the Micro LED chip 130 and the Micro IC 180 can be fixed. As a preferred method, the coating height of the transparent encapsulation layer 210 on the surface of the first substrate 170 can be higher than the height of the Micro LED chip 130 and the Micro IC 180 as a whole. In this way, after the transparent encapsulation layer 210 is cured, the transparent encapsulation layer 210 can be polished or ground to form a packaging plane 240 with good flatness and parallel to the first substrate 170.

[0131] In step S107 , after the transparent encapsulation layer 210 is cured, the first substrate 170 is removed, so that the transparent encapsulation layer 210 forms a first plane 250 exposing the electrodes 140 of the Micro LED chip 130 and the electrodes 190 of the Micro IC 180 .

[0132] Since the Micro LED chip 130 and the Micro IC 180 are in contact with the first adhesive layer 190 of the first substrate 170 at the ends where the electrodes are located, when the Micro LED chip 130 and the Micro IC 180 are separated from the first substrate 170 , the electrodes of the Micro LED chip 130 and the Micro IC 180 will be exposed from the first plane 250 of the transparent encapsulation layer 210 .

[0133] Step S108 , manufacturing the RDL 220 on the first plane 250 .

[0134] The RDL 220 includes an insulating flat layer and a plurality of RDL lines distributed in the insulating flat layer. The insulating flat layer can be made of silicon or a polymer material, and the RDL line can be made of a conductive material such as copper through semiconductor process technologies such as photolithography, evaporation, and electroplating. The RDL line can be a single-layer line or a multi-layer line, which is not limited in the present embodiment of the application.

[0135] Among them, according to the different directions of the RDL lines, the RDL lines can be divided into two parts. The first part of the RDL lines is used to connect the electrodes 140 of the Micro LED chip 130 and the electrodes 190 of the Micro IC 180, so that each Micro IC 180 establishes an electrical connection with at least one Micro LED chip 130 through the RDL 220; one end of the second part of the RDL line is connected to the electrode 190 of the Micro IC 180, and the other end is exposed on the lower surface 260 of the RDL 220, so if an external driving signal is introduced to the other end of the second part of the RDL line, the driving signal can be transmitted to the Micro IC 180.

[0136] In step S109 , a solder pad 270 and a solder bump 330 are fabricated on the lower surface 260 of the RDL 220 .

[0137] Among them, the pad 270 is connected to the other end of the second part of the RDL line, so the pad 270 and the Micro IC 180 can be electrically connected through the RDL 220, and the solder bump 330 is made on the pad 270 to facilitate the connection between the pad 270 and external devices such as the driving backplane.

[0138] After this step is completed, a complete Micro LED chip packaging module is obtained, and the module can be mechanically and electrically connected to other modules or drive systems such as a driving backplane or a display driver IC (Display driver IC, DDIC) through the pad 270 to obtain a complete display screen.

[0139] When the Micro LED chip packaging module is driven by an external driving signal, the driving signal first controls the Micro IC 180, and then the Micro IC 180 controls the working state of at least one Micro LED chip 130 connected to it according to the driving signal. This can reduce the number of pads between the Micro LED chip packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, even much larger than the size of the Micro LED chip, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0140] In one embodiment, Figure 8As shown, after the Micro LED chip 130 and the Micro IC 180 are transferred to the first substrate 170, and before the transparent encapsulation layer 210 is coated on the surface of the Micro LED chip 130, the Micro IC 180 and the first substrate 170, that is, between step S105 and step S106, a light isolation structure 280, a black matrix (blackmatrix), etc. can also be made between adjacent pixels, or between the Micro LED chips 130, or between the Micro LED chip 130 and the Micro IC 180 to prevent light from leaking from the gaps between pixels, reduce cross-talk between pixels, increase or converge the viewing angle of the light emitted by the Micro LED chip 130, and improve the light emission efficiency, etc., thereby improving the display effect of the Micro LED display.

[0141] In one embodiment, Fig. 9 As shown, when a pixel includes multiple Micro LED chips 130 emitting the same color light, in order to obtain a full-color pixel, after the Micro LED chip 130 and the Micro IC 180 are transferred to the first substrate 170, and before the transparent encapsulation layer 210 is coated on the surface of the Micro LED chip 130, the Micro IC 180 and the first substrate 170, that is, between step S105 and step S106, a color conversion material 290 can also be coated on part or all of the Micro LED chips 130 in the pixel, so that different Micro LED chips 130 emit different colors of light through the color conversion material. For example, when the pixel includes three Micro LED chips 130 emitting blue light, one of the Micro LED chips 130 can be coated with a red color conversion material 290, and another Micro LED chip 130 can be coated with a green color conversion material 290, so that the three Micro LED chips 130 in the pixel finally emit red, green and blue light, forming an RBG full-color pixel.

[0142] In one embodiment, Fig.10 As shown, before applying the color conversion material 290, a light isolation structure 280, a black matrix, etc. can be made between pixels, or between Micro LED chips 130, or between Micro LED chips 130 and Micro IC 180 to separate color conversion materials 290 of different colors, and ultimately improve the display effect of the LED chip packaging module and the display screen it constitutes.

[0143] In one embodiment, Fig.11As shown, after the transparent encapsulation layer 210 is coated on the surface of the Micro LED chip 130, the Micro IC 180 and the first substrate 170 (i.e. after step S106), a micro-nano structure 310 can be made on the encapsulation plane 240 of the transparent encapsulation layer 210 to improve the luminous efficiency of the Micro LED display, improve the luminous field, or achieve other optical property improvement effects. For example, the above-mentioned micro-nano structure 310 can be, for example, a densely arranged stripe-shaped protrusion structure.

[0144] The embodiment of the present application further provides an LED chip packaging module, which can be obtained using the method described above in the embodiment of the present application, or can be obtained using other manufacturing methods.

[0145] Fig.12 Schematic diagram of a structure of an LED chip packaging module according to an embodiment of the present application. Fig.12 As shown, the LED chip packaging module includes an RDL 220 , a plurality of Micro LED chips 130 , at least one Micro IC 180 , and a transparent packaging layer 210 .

[0146] Among them, the above-mentioned multiple Micro LED chips 130 and at least one Micro IC 180 are distributed on the upper surface 320 of the RDL 220, each Micro LED chip 130 is provided with at least one electrode 140 facing the upper surface 320 of the RDL 220 and connected to the RDL 220, each Micro IC 180 is provided with at least one electrode 230 facing the upper surface 320 of the RDL 220 and connected to the RDL 220, and each Micro IC 180 establishes an electrical connection with at least one Micro LED chip 130 through the RDL 220. The transparent encapsulation layer 210 is coated on the upper surface 320 of the RDL 220. The thickness of the transparent encapsulation layer 210 in a direction perpendicular to the upper surface 320 of the RDL 220 is greater than or equal to the thickness of the Micro LED chip 130 and the Micro IC 180 in a direction perpendicular to the upper surface 320 of the RDL 220, so that the transparent encapsulation layer 210 can cover the above-mentioned Micro LED chip 130 and the Micro IC 180. The transparent encapsulation layer 210 can also form a packaging plane 240 parallel to the RDL 220 through polishing. The lower surface 260 of the RDL 220 is also provided with at least one pad 270, and each pad 270 is electrically connected to at least one Micro IC 180 through the RDL 220. Each pad 270 can also be made into a solder bump 330 to facilitate welding the pad 270 of the RDL 220 with the pad on the driving backplane of the display screen, so that the LED chip packaging module is mechanically and electrically connected to the driving backplane.

[0147] In the implementation of this application, Micro IC 180 can be arranged in a variety of ways relative to RDL 220. For example:

[0148] (1) The Micro IC 180 can be completely disposed on the upper surface 320 of the RDL 220, such as Fig.12 shown.

[0149] (2) Micro IC 180 can be completely set on the lower surface 260 of RDL 220. This arrangement allows the upper surface 320 of RDL 220 to only be used to set Micro LED chips 130, and no space is required for Micro IC 180, which is beneficial to improving the pixel density of the LED chip packaging module and improving the display effect. In addition, Micro IC 180 can have a larger setting space and a more flexible layout on the lower surface 260 of RDL 220, so that a larger and more powerful Micro IC 180 can be placed, thereby improving the performance of the LED chip packaging module.

[0150] (3) A portion of the Micro IC 180 is disposed on the upper surface 320 of the RDL 220, while another portion of the Micro IC 180 is disposed on the lower surface 260 of the RDL 220. In this configuration, the Micro IC 180 on the upper surface 320 and the Micro IC 180 on the lower surface 260 can each control a portion of the Micro LED chip 130, and the Micro IC 180 on the upper surface 320 and the Micro IC 180 on the lower surface 260 can control the same or different Micro LED chips 130. This configuration allows the upper surface 320 of the RDL 220 to only reserve space for a portion of the Micro IC 180, thereby helping to improve the pixel density of the LED chip packaging module and the display effect. In one implementation, a smaller Micro IC 180 can be disposed on the upper surface 320 of the RDL 220, while a larger Micro IC 180 can be disposed on the lower surface 260 of the RDL 220, thereby maximizing the surface space utilization of the RDL 220.

[0151] It should be noted that when the lower surface 260 of the RDL 220 is provided with a Micro IC 180, the height of the Micro IC 180 in a direction perpendicular to the lower surface 260 should be less than the sum of the heights of the solder pad 270 and the solder ball 330, so that the Micro IC 180 will not affect the soldering of the LED chip packaging module to the driving backplane of the display screen.

[0152] In one embodiment, Fig.12 As shown, the RDL 221 includes an insulating flat layer 221 and a plurality of RDL lines distributed in the insulating flat layer 221. For ease of description, the RDL lines are divided into a first RDL line 222 and a second RDL line 223 according to the direction of the RDL lines and the different devices connected thereto, and the two ends of the first RDL line 222 are respectively referred to as a first end 2221 and a second end 2222, and the two ends of the second RDL line 223 are respectively referred to as a third end 2231 and a fourth end 2232. The first end 2221 and the second end 2222 of the first RDL are located on the upper surface 320 of the RDL 220, the third end 2231 of the second RDL line 223 is located on the upper surface 320 of the RDL 220, and the fourth end 2232 of the second RDL line 223 is located on the lower surface 260 of the RDL 220. The fourth end 2232 of the second RDL line 223 may be provided with a pad 270 for electrical connection with other devices. The first end 2221 of the first RDL line 222 is used to connect to the electrode 140 of the Micro LED chip 130. Each first RDL line 222 may have at least one first end 2221, which is used to connect to the electrode 140 of at least one Micro LED chip 130. The second end 2222 of the first RDL line 222 is used to connect to the electrode 230 of the Micro IC 180. The electrode 230 of each Micro IC 180 may be connected to the second end 2222 of at least one first RDL line 222. The third end 2231 of the second RDL line 223 is used to connect to the electrode 230 of the Micro IC 180. The third end 2231 of each second RDL line 223 may be connected to the electrode 230 of at least one Micro IC 180. The second end 2222 of the first RDL line 222 and the third end 2231 of the second RDL line 223 are connected to different electrodes 230. A solder ball 330 is disposed on the pad 270 of the fourth end 2232 of the second RDL line 223 to facilitate connection with an external device and receive an external driving signal.

[0153] When the Micro LED chip packaging module provided in the embodiment of the present application is driven by an external driving signal, the driving signal first controls the Micro IC 180, and then the Micro IC 180 controls the working state of at least one Micro LED chip 130 connected thereto according to the driving signal. This can reduce the number of I / O pads between the Micro LED chip packaging module and external devices such as a driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, even much larger than the size of the Micro LED chip, thereby greatly reducing the difficulty of bonding between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0154] In one embodiment, Fig.13 As shown, the Micro LED chips 130 in the LED chip packaging module can form a plurality of pixels in a certain arrangement, wherein each pixel includes at least one Micro LED chip 130. If a full-color pixel arrangement is to be formed, each pixel can include three Micro LED chips 130, for example: a Micro LED chip B emitting blue light, a Micro LED chip G emitting green light, and a Micro LED chip R emitting red light, and these three chips can be located in the same row to form a standard RGB arrangement. In addition, each pixel can also include a Micro IC 180, which is electrically connected to the three Micro LED chips 130 in the pixel through the RDL 220, and is used to control the working status of the three Micro LED chips 130, such as the lighting time, intensity, etc., so that the pixel can display various colors. At this time, each Micro IC 180 is only used to control the working status of one pixel.

[0155] In one embodiment, Fig.14 As shown, each pixel may include three Micro LED chips 130 and one Micro IC 180, wherein the three Micro LED chips 130 may be located in the same row to form a standard RGB arrangement, while the Micro IC 180 may be arranged separately in another row.

[0156] It is understandable that, in addition to the arrangement shown in the embodiment of the present application, the Micro LED chip 130 may also have other arrangements, such as: pentile arrangement, RGB-Delta arrangement, etc., which is not limited in the embodiment of the present application.

[0157] In one embodiment, Fig.15 As shown, each pixel may include three Micro LED chips 130 to form a standard RGB arrangement. In each row or column of pixels, a Micro IC 180 may be provided for every certain number N (N is a positive integer greater than 1) of pixels, and each Micro IC 180 may establish an electrical connection with each Micro LED chip 130 in the adjacent N pixels in its row or column through RDL to control the working state of each Micro LED chip 130 in the adjacent N pixels.

[0158] It is understandable that when each Micro IC 180 is used to control the color display of N pixels, the Micro IC 180 can also be set between pixels in other distribution methods, and each Micro IC 180 can establish an electrical connection with multiple adjacent pixels through RDL to control the color display of these pixels. The embodiments of the present application are not limited to this.

[0159] In one embodiment, Fig.16 As shown, some or all of the Micro LED chips 130 in each pixel may be Micro LED chips that emit the same color light, and in this case, the surfaces of some or all of the Micro LED chips 130 may be coated with a color conversion material, which is used to convert the color light emitted by the Micro LED chips 130 into other colors. For example, when a pixel contains three Micro LED chips 130 that emit blue light, in order to obtain a full-color pixel, a red color conversion material 290R may be coated on the surface of one of the Micro LED chips 130 to convert the blue light emitted by it into red light, and a green color conversion material 290G may be coated on the surface of another Micro LED chip 130 to convert the blue light emitted by it into green light.

[0160] In one embodiment, Fig.16 As shown, a light isolation structure 280 may be provided between the Micro LED chip 130 and the Micro IC 180, and a light isolation structure 280 may also be provided between two adjacent Micro LED chips 130. One end of the light isolation structure 280 is connected to the RDL 220, and the other end extends away from the RDL 220. The light isolation structure 280 is conducive to improving the luminous efficiency of the Micro LED chip 130, reducing the cross-talk between pixels, increasing or converging the luminous viewing angle of the Micro LED chip 130, and separating the color conversion materials 290 of different colors, and finally improving the display effect of the LED chip packaging module and the display screen composed thereof.

[0161] It is understandable that in order to achieve the purpose of improving the display effect of the LED chip packaging module and the display screen formed by it, the LED chip packaging module can include not only the light isolation structure 280, but also structures such as a black dot matrix, and the embodiments of the present application do not limit this.

[0162] In some embodiments, the encapsulation plane 240 of the transparent encapsulation layer 210 has a micro-nano structure 310, which can be, for example, a densely arranged stripe-shaped protrusion structure. The micro-nano structure 310 is beneficial for improving the luminous efficiency of the Micro LED display, improving the luminous field, and achieving other optical property improvement effects.

[0163] In one embodiment, each pixel of the LED chip packaging module may also include at least one backup Micro LED chip. When the LED chip packaging module is detected and it is found that the main Micro LED chip in a certain pixel fails, the Micro IC can drive the backup Micro LED chip of the pixel to replace the failed Micro LED chip, so that the pixel can still display colors normally, thereby maintaining the display integrity of the LED chip packaging module and improving the yield of the LED chip packaging module.

[0164] In one embodiment, Fig.17 As shown, each main Micro LED chip in a pixel can correspond to a backup Micro LED chip with the same light color as it, so a full-color pixel can include six Micro LED chips, namely: two red Micro LED chips R1 and R2, two green Micro LED chips G1 and G2, and two blue Micro LED chips B1 and B2. When all the main Micro LED chips are normal, the backup Micro LED chips do not work, and the Micro IC only drives the main chip to work; when any main Micro LED chip fails, the Micro IC can drive the backup Micro LED chip of the same color to replace the failed Micro LED chip.

[0165] For example, when the main green-light-emitting Micro LED chip G1 fails but is in an open circuit state or the leakage current is lower than a threshold value (the threshold value may be, for example, 1% of the normal driving current), the Micro IC may directly drive the backup green-light-emitting Micro LED chip G2. When the main green-light-emitting Micro LED chip G1 fails but is in a connected state or the leakage current is higher than the threshold value, the failed green-light-emitting Micro LED chip G1 or its corresponding circuit may be first destroyed by laser to make the failed chip in an open circuit state, and then the backup green-light-emitting Micro LED chip G2 may be driven.

[0166] In one embodiment, Fig.18As shown, since the probability of two Micro LED chips failing in a pixel is much lower than the probability of one Micro LED chip failing, each pixel can also contain only one spare Micro LED chip, thereby improving the size utilization of the LED chip packaging module, increasing pixel density and reducing costs.

[0167] For example, a full-color pixel may include four Micro LED chips, namely: a Micro LED chip R1 that mainly emits red light, a Micro LED chip G1 that mainly emits green light, a Micro LED chip B1 that mainly emits blue light, and a spare Micro LED chip B2. Assuming that the spare Micro LED chip emits blue light, then when the main Micro LED chip B1 that emits blue light fails, the Micro IC can directly drive the spare Micro LED chip B2. When the main Micro LED chip R1 or G1 that emits red or green light fails, the transparent encapsulation layer 210 around the spare Micro LED chip B2 can be first removed by laser, and then the color conversion material 290 with the same color as the failed Micro LED chip can be sprayed, so that the spare Micro LED chip B2 can emit the same color light as the failed Micro LED chip after being driven by the Micro IC.

[0168] In other embodiments, a spare Micro LED chip can also be used to replace a failed Micro LED chip in more than one pixel, thereby reducing the number of spare Micro LED chips, improving the size utilization of the LED chip packaging module, increasing pixel density, and reducing costs.

[0169] For example, Fig.19As shown, a full-color pixel can include three Micro LED chips, namely: a red Micro LED chip R1, a green Micro LED chip G1 and a blue Micro LED chip B1, and these three Micro LED chips can be arranged in a triangle. Among them, the red Micro LED chip R1 and the green Micro LED chip G1 are arranged in parallel in the same row, and the blue Micro LED chip B1 is located above the other two chips. The spare Micro LED chip can be a blue Micro LED chip B2, which is arranged between the blue Micro LED chips B1 of two adjacent pixels, forming an arrangement in which the main and spare Micro LED chips are alternately arranged in the same row. Under this arrangement, when the blue-light-emitting Micro LED chip B1 of a certain pixel fails, the Micro IC can directly choose to drive an adjacent spare Micro LED chip B2. When the red-light or green-light-emitting Micro LED chip R1 or G1 of a certain pixel fails, the transparent packaging layer around the spare Micro LED chip B2 closest to the failed chip can be first removed by laser, and then the color conversion material of the same color as the failed Micro LED chip can be sprayed, so that the spare Micro LED chip B2 can emit the same color light as the failed Micro LED chip after being driven by the Micro IC.

[0170] For example, Fig. 20 As shown, the three Micro LED chips in the full-color pixel can form a standard RGB arrangement. Then, every two adjacent pixels in the same row or column are grouped together, and a spare Micro LED chip B2 is set between the two pixels, so that the spare Micro LED chip B2 can be used to replace the failed Micro LED chip in this group of pixels.

[0171] Understandably, Figure 17-Figure 20 The various implementation methods shown are only used to exemplarily illustrate the technical concept of the embodiments of the present application and do not constitute specific limitations on the embodiments of the present application. In addition to the implementation methods shown above, technical personnel in this field may also adopt other implementation methods inspired by this technical concept, which do not exceed the protection scope of the embodiments of the present application.

[0172] It should be noted that there are currently two light-emitting directions for Micro LED chips, one is back-emitting, that is, the light emitted by the Micro LED chip does not pass through the RDL to the external environment, and the other is front-emitting, that is, the light emitted by the Micro LED chip needs to pass through the RDL to the external environment. When the Micro LED chip is back-emitting, the insulating flat layer in the RDL can be made of an opaque material with an opaque property, so that it can absorb or reflect the light emitted by the Micro LED chip to increase the light output. When the Micro LED chip is front-emitting, the insulating flat layer in the RDL can be made of an opaque material with a high penetration or transparent property, so that the light emitted by the Micro LED chip can efficiently pass through the RDL to increase the light output.

[0173] The present application also provides another LED chip packaging method, such as Fig.21 As shown, the method may include the following steps:

[0174] Step S101-Step S104, and Figure 4 Steps S101 to S104 are shown to be the same and will not be described again here.

[0175] In step S110 , the Micro LED chips 130 are detachably arranged on the first substrate 170 , wherein the electrodes 140 of the Micro LED chips 130 are placed facing the first substrate 170 .

[0176] The difference between step S110 and step S105 is that in step S110 , the Micro IC 180 is not placed on the first substrate 107 .

[0177] In one embodiment, a plurality of Micro LED chips 130 may be arranged into a plurality of pixels on the first substrate 170 , and each pixel includes at least one Micro LED chip 130 .

[0178] For example, Fig. 22 As shown in the a arrangement, the pixel contains a Micro LED chip B that emits blue light, a Micro LED chip G that emits green light, and a Micro LED chip R that emits red light. These three Micro LED chips are arranged in a row to form a standard RGB arrangement.

[0179] For example, Fig. 22As shown in the b arrangement, a pixel can contain four Micro LED chips, such as two Micro LED chips B that emit blue light, one Micro LED chip R that emits red light, and one Micro LED chip G that emits green light. These four Micro LED chips form a rectangular arrangement. The position of each Micro LED chip can be regarded as a corner point of the rectangle, and the two Micro LED chips B that emit blue light are set diagonally.

[0180] The first adhesive layer 190 is disposed on the surface of the first substrate 170, which can temporarily fix the Micro LED chip 130 detachably without damaging the device structure of the Micro LED chip 130. When the Micro LED chip is detachably placed on the first substrate 170, the end where the electrode of the Micro LED chip 130 is located contacts the first adhesive layer 190 of the first substrate 170.

[0181] In step S111 , a transparent encapsulation layer 210 is coated on the surfaces of the Micro LED chip 130 and the first substrate 170 .

[0182] The transparent encapsulation layer 210 may include, for example, epoxy resin and silicone resin materials. The transparent encapsulation layer 210 needs to be cured for a certain period of time after coating, and after curing, the relative positions of the Micro LED chips 130 can be fixed. As a preferred method, the coating height of the transparent encapsulation layer 210 on the surface of the first substrate 170 can be higher than the height of the Micro LED chip 130 as a whole, so that after the transparent encapsulation layer 210 is cured, the transparent encapsulation layer 210 can be polished or ground to form a packaging plane 240 with good flatness and parallel to the first substrate 170.

[0183] In step S112 , after the transparent encapsulation layer 210 is cured, the first substrate 170 is removed so that the transparent encapsulation layer 210 forms a first plane 250 exposing the electrodes of the Micro LED chip 130 .

[0184] Since the Micro LED chip 130 is in contact with the first adhesive layer 190 of the first substrate 170 at the end where the electrode is located, when the Micro LED chip 130 is separated from the first substrate 170 , the electrode of the Micro LED chip 130 will be exposed from the first plane 250 of the transparent encapsulation layer 210 .

[0185] Step S113 , manufacturing the RDL 220 on the first plane 250 .

[0186] The RDL 220 includes an insulating flat layer and a plurality of RDL lines distributed in the insulating flat layer. The insulating flat layer can be made of silicon or a polymer material, and the RDL line can be made of a conductive material such as copper through semiconductor process technologies such as photolithography, evaporation, and electroplating. The RDL line can be a single-layer line or a multi-layer line, which is not limited in the embodiments of the present application.

[0187] Among them, according to the different directions of the RDL lines, the RDL lines can be divided into two parts. One end of the first part of the RDL line is connected to the electrode of the Micro LED chip 130, and the other end is exposed on the lower surface 260 of the RDL 220. Both ends of the second part of the RDL line are exposed on the lower surface 260 of the RDL 220.

[0188] Step S114 , mounting at least one Micro IC 180 on the lower surface 260 of the RDL.

[0189] Among them, a part of the electrodes of Micro IC 180 is connected to the first part of the RDL line to realize the electrical connection between Micro IC 180 and at least one Micro LED chip 130 through RDL 221; another part of Micro IC 180 is connected to one end of the second part of the RDL line, so if an external driving signal is introduced to the other end of the second part of the RDL line, the driving signal can be transmitted to Micro IC 180.

[0190] In step S115 , a solder pad 270 and a solder bump 330 are fabricated on the lower surface 260 of the RDL 220 .

[0191] Among them, the pad 270 is connected to the other end of the second part of the RDL line, so the pad 270 and the Micro IC 180 can be electrically connected through the RDL, and the solder bump 330 is made on the pad 270 to facilitate the connection between the pad 270 and external devices such as the driving backplane.

[0192] After this step is completed, a complete Micro LED chip packaging module is obtained, and the module can be mechanically and electrically connected to a module or a driving system such as a driving backplane or a display driver IC (DDIC) through solder balls 330 to obtain a complete display screen.

[0193] When the Micro LED chip packaging module is driven by an external driving signal, the driving signal first controls the Micro IC 180, and then the Micro IC 180 controls the working state of at least one Micro LED chip 130 connected to it according to the driving signal. This can reduce the number of I / O pads between the Micro LED chip packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, even much larger than the size of the Micro LED chip, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0194] according to Fig.21 The Micro LED chip packaging module made by the method can also increase Figure 8-11 The structure shown is used to achieve the corresponding characteristics. Due to space limitations, it will not be repeated here.

[0195] The present application also provides an LED chip packaging module. The LED chip packaging module can be used in the present application. Fig.21 The method shown in the figure can be used to obtain the quartz crystal, and other production methods can also be used to obtain the quartz crystal.

[0196] Fig.23 FIG. 1 is another structural schematic diagram of the LED chip packaging module of the embodiment of the present application. Fig.24 As shown, the LED chip packaging module includes an RDL 220 , a plurality of Micro LED chips 130 , at least one Micro IC 180 , and a transparent packaging layer 210 .

[0197] Among them, the above-mentioned multiple Micro LED chips 130 are distributed on the upper surface 320 of the RDL 220, and each Micro LED chip 130 is provided with at least one electrode 140 facing the upper surface 320 of the RDL 220 and connected to the RDL 220; the above-mentioned at least one Micro IC 180 is distributed on the lower surface 260 of the RDL 220, and each Micro IC 180 is provided with at least one electrode 230 facing the lower surface 260 of the RDL 220 and connected to the RDL 220, and each Micro IC 180 establishes an electrical connection with at least one Micro LED chip 130 through the RDL 220. The transparent encapsulation layer 210 is coated on the upper surface 320 of the RDL 220. The thickness of the transparent encapsulation layer 210 in a direction perpendicular to the upper surface 320 of the RDL 220 is greater than or equal to the thickness of the Micro LED chip 130 in a direction perpendicular to the upper surface 320 of the RDL 220, so that the transparent encapsulation layer 210 can cover the above-mentioned Micro LED chip 130. The transparent encapsulation layer 210 can also form a packaging plane 240 parallel to the RDL 220 through polishing. The lower surface 260 of the RDL 220 is also provided with at least one pad 270, and each pad 270 is electrically connected to at least one Micro IC 180 through the RDL 220. Each pad 270 can also be made into a solder bump 330 to facilitate welding the pad 270 of the RDL 220 with the pad on the driving backplane of the display screen, so that the LED chip packaging module is mechanically and electrically connected to the driving backplane.

[0198] Further Fig.23As shown, the RDL 221 includes an insulating flat layer 221 and a plurality of RDL lines distributed in the insulating flat layer 221. For ease of description, the RDL lines are divided into a first RDL line 222 and a second RDL line 223 according to the direction of the RDL lines and the devices connected thereto. The two ends of the first RDL line 222 are respectively referred to as a first end 2221 and a second end 2222, and the two ends of the second RDL line 223 are respectively referred to as a third end 2231 and a fourth end 2232. The first end 2221 of the first RDL line 222 is located on the upper surface 320 of the RDL 220, the second end 2222 of the first RDL line 222 is located on the lower surface 360 ​​of the RDL 220, and the third end 2231 and the fourth end 2232 of the second RDL line 223 are both located on the lower surface 260 of the RDL 220. The fourth end 2232 of the second RDL line 223 may be provided with a pad for electrical connection with other devices. The first end 2221 of the first RDL line 222 is used to connect to the electrode 140 of the Micro LED chip 130. Each first RDL line 222 may have at least one first end 2221, which is used to connect to the electrode 140 of at least one Micro LED chip 130. The second end 2222 of the first RDL line 222 is used to connect to the electrode 230 of the Micro IC 180. The electrode 230 of each Micro IC 180 may be connected to the second end 2222 of at least one first RDL line 222. The third end 2231 of the second RDL line 223 is used to connect to the electrode 230 of the Micro IC 180. The third end 2231 of each second RDL line 223 may be connected to the electrode 230 of at least one Micro IC 180. The second end 2222 of the first RDL line 222 and the third end 2231 of the second RDL line 223 are connected to different electrodes 230. A solder ball 330 is disposed on the pad 270 of the fourth end 2232 of the second RDL line 223 to facilitate connection with an external device and receive an external driving signal.

[0199] When the Micro LED chip packaging module provided in the embodiment of the present application is driven by an external driving signal, the driving signal first controls the Micro IC 180, and then the Micro IC 180 controls the working state of at least one Micro LED chip 130 connected thereto according to the driving signal. This can reduce the number of I / O pads between the Micro LED chip packaging module and external devices such as a driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, even much larger than the size of the Micro LED chip, thereby greatly reducing the difficulty of bonding between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0200] In the embodiment of the present application, the Micro LED chip 130 can form a standard RGB arrangement, a pentile arrangement, an RGB-Delta arrangement, and the like. Figure 17-Figure 20 The arrangement shown or other arrangements will not be described in detail here.

[0201] The present application also provides another LED chip packaging method, such as Fig.24 As shown, the method includes Fig.21 The same steps S101-S104, S110-S112, and:

[0202] Step S116 , manufacturing the RDL 220 on the first plane 250 .

[0203] The RDL 220 includes an insulating planar layer and a plurality of RDL lines distributed in the insulating planar layer. One end of each RDL line is connected to the electrode 140 of at least one Micro LED chip, and the other end is exposed on the lower surface 260 .

[0204] Step S117 , making pads 270 connected to the RDL circuit on the lower surface 260 .

[0205] Each pad 270 may be connected to one or more RDL lines. When each pad is connected to multiple RDL lines, the pad 270 may be of irregular shape according to different exposed positions of the RDL lines connected to each pad 270 on the lower surface 260 .

[0206] After this step is completed, a complete Micro LED chip packaging module is obtained, and the module can be mechanically and electrically connected to other modules or drive systems such as a driving backplane or a display driver IC (Display driver IC, DDIC) through the pad 270 to obtain a complete display screen.

[0207] When the Micro LED chip packaging module is driven by an external driving signal, the driving signal is directly sent to at least one Micro LED chip 130 through the pad 270 and the RDL220, so that one driving signal controls one or more Micro LED chips 130. This can reduce the number of pads between the packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, even much larger than the size of the Micro LED chip, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0208] The present application also provides an LED chip packaging module. The LED chip packaging module can be used in the present application. Fig.24 The method shown in the figure can be used to obtain the quartz crystal, and other production methods can also be used to obtain the quartz crystal.

[0209] Fig.25 FIG. 1 is another structural schematic diagram of the LED chip packaging module of the embodiment of the present application. Fig.25 As shown, the LED chip packaging module includes an RDL 220 , a plurality of Micro LED chips 130 , and a transparent packaging layer 210 .

[0210] The plurality of Micro LED chips 130 are distributed on the upper surface 320 of the RDL 220, and each Micro LED chip 130 is provided with at least one electrode 140 facing the upper surface 320 of the RDL 220 and connected to the RDL 220; the transparent encapsulation layer 210 is coated on the upper surface 320 of the RDL 220, and the thickness of the transparent encapsulation layer 210 in a direction perpendicular to the upper surface 320 of the RDL 220 is greater than or equal to the thickness of the Micro LED chip 130 in a direction perpendicular to the upper surface 320 of the RDL 220, so that the transparent encapsulation layer 210 can cover the Micro LED chip 130, and the transparent encapsulation layer 210 can also form a packaging plane 240 parallel to the RDL 220 through polishing. The lower surface 260 of the RDL 220 is also provided with at least one pad 270, and each pad 270 is electrically connected to at least one Micro LED chip 130 through the RDL 220. The at least one soldering pad 270 can be soldered together with the soldering pad 340 on the driving backplane 300 of the display screen, so that the LED chip packaging module is mechanically and electrically connected to the driving backplane.

[0211] Fig.26 This is an example diagram of the pads and RDL circuits of the LED chip packaging module. Fig.26 As shown in the figure, when a pixel includes three Micro LED chips, and each Micro LED chip includes a p-type ohmic electrode and an n-type ohmic electrode, the number of corresponding pads 270 can be 4. Among them, the p-type ohmic electrode of each Micro LED chip can correspond to a pad 270, and each p-type ohmic electrode is connected to its corresponding pad 270 through an RDL line 224. In addition, another pad 270 can be additionally connected to the three n-type ohmic electrodes of the three Micro LED chips through an RDL line 225. Therefore, a pixel only needs four pads 270 to the outside, and if using Figure 1According to the method shown in the figure, one pixel needs to have six pads to the outside, so it can be seen that the LED chip packaging module provided by the embodiment of the present application can reduce the number of external I / O pads. In addition, since the number of external I / O pads of the LED chip packaging module is reduced, the size of the pad 270 can be enlarged while the size of the LED chip packaging module remains unchanged, and the size of the pad 340 on the driving backplane 300 that is aligned with the pad 270 can be enlarged (such as Fig.25 ), thereby reducing the difficulty of binding the LED chip packaging module and the driving backplane 300 and improving the product yield.

[0212] When the Micro LED chip packaging module provided in the embodiment of the present application is driven by an external driving signal, the driving signal is directly sent to at least one Micro LED chip 130 through the pad 270 and the RDL 220, so that one driving signal controls one or more Micro LED chips 130. This can reduce the number of pads between the packaging module and external devices such as the driving backplane, so that under the same LED chip packaging module and driving backplane size, the size of each pad can be larger, even much larger than the size of the Micro LED chip, thereby greatly reducing the bonding difficulty between the LED chip packaging module and the driving backplane, which is conducive to improving product yield.

[0213] In the embodiment of the present application, the Micro LED chip 130 can form a standard RGB arrangement, a pentile arrangement, an RGB-Delta arrangement, and the like. Figure 17-Figure 20 The arrangement shown or other arrangements will not be described in detail here.

[0214] It can be understood that, based on the various embodiments of the LED chip packaging module provided in this application, such as Fig.12 , Fig.23 and Fig.25 Two or three of the structures shown may also appear simultaneously in one LED chip packaging module. Due to space limitations, this will not be further described in the embodiments of the present application.

[0215] The present application also provides a Micro LED display screen, such as Fig. 27 As shown, the display screen may include a driving backplane 300, a DDIC 400 and at least one LED chip packaging module 200 provided in the aforementioned embodiments of the present application.

[0216] The driving backplane 300 may be, for example, a glass backplane, a film substrate, a plastic backplane, a TFT backplane, etc. Accordingly, the DDIC 400 may be packaged on the driving backplane 300 using packaging technologies such as chip on plastic (COP), chip on film (COF), or chip on glass (COG).

[0217] A plurality of pads 340 are provided on the driving backplane 300, and these pads 340 correspond to the positions of the pads 270 of the LED chip packaging module 200. The LED chip packaging module 200 and the driving backplane 300 can be packaged together using packaging technology such as SMT, so that the pads 340 on the driving backplane 300 and the pads 270 of the LED chip packaging module 200 are welded together in a one-to-one correspondence to form an electrical and mechanical connection. The pads 340 on the driving backplane 300 are also connected to the DDIC 400 through a line, so that the driving signal of the DDIC 400 can be delivered to the LED chip packaging module 200.

[0218] In one embodiment, the Micro LED display screen may include only one LED chip packaging module 200. Such a display screen may be applied to electronic devices with smaller display screens, such as smart bracelets, smart watches, etc. In this case, the number of pads 340 of the driving backplane 300 may be the same as the number of pads 270 of an LED chip packaging module 200, or the number of pads 340 may be not less than the number of pads 270 of an LED chip packaging module 200.

[0219] According to the technical solution of the embodiment of the present application, when the Micro LED display includes an LED chip packaging module 200, and the LED chip packaging module 200 includes X (columns) × Y (rows) pixels, the number of external pads 270 of the LED chip packaging module 200 can range from X+Y to X×Y×Z, where Z is the number of external I / Os for each pixel. Correspondingly, the number of pads 340 of the driving backplane 300 can also range from X+Y to X×Y×Z.

[0220] For example, when the DDIC 400 drives each pixel in the LED chip package module 200 using the scan line and data line architecture, the number of external pads 270 of the LED chip package module 200 can be only X+Y+M, where M is a few necessary pads corresponding to the clock signal clock and the ground signal ground. Correspondingly, the number of pads 340 of the driving backplane can also be X+Y+M.

[0221] In one embodiment, the Micro LED display screen may only include multiple LED chip packaging modules 200, and the multiple LED chip packaging modules 200 are spliced ​​on the driving backplane 300 to form a complete display area. Such display screens can be used in electronic devices with small and large sizes, such as: smart bracelets, smart watches, mobile phones, tablet computers, e-readers, televisions, monitors, virtual / mixed / augmented reality devices, etc. In this case, the number of pads 340 of the driving backplane 300 can be the same as the total number of pads 270 of the multiple LED chip packaging modules 200, or the number of pads 340 can also be not less than the total number of pads 270 of the multiple LED chip packaging modules 200.

[0222] According to the technical solution of the embodiment of the present application, when the Micro LED display includes K LED chip packaging modules 200, and each LED chip packaging module 200 includes X (columns) × Y (rows) pixels, the total number of external pads 270 of the K LED chip packaging modules 200 can range from (X+Y)×K to X×Y×Z×K, where Z is the number of external I / Os for each pixel. Correspondingly, the number of pads 340 of the driving backplane 300 can also range from (X+Y)×K to X×Y×Z×K.

[0223] For example, when the DDIC 400 drives each pixel in the LED chip package module 200 using the scan line and data line architecture, the number of external pads 270 of each LED chip package module 200 can be only X+Y+M, where M is a few necessary pads corresponding to the clock signal clock and the ground signal ground. Correspondingly, the number of pads 340 of the driving backplane 300 can also be (X+Y+M)×K.

[0224] Further Fig.28 As shown, it should be supplemented that, when two adjacent LED chip packaging modules 200 are spliced, in order to avoid the splicing gap or offset between the two LED chip packaging modules 200 being noticed by the user, the spacing Y1 between two adjacent Micro LED pixels between two adjacent LED chip packaging modules 200 can be within a certain range, preferably between 0.5-2 times the pixel spacing Y0 in the LED chip packaging module 200; and the angular deviation Δθ between two adjacent LED chip packaging modules 200 is less than a certain angle threshold, preferably the threshold is 5°, thereby achieving the effect of seamless splicing of two adjacent LED chip packaging modules 200 from the user's perspective.

[0225] For example, for a general display screen, a black matrix or other light-isolating structure can be provided between pixels, and the width of the light-isolating structure constitutes a part of the pixel pitch. However, when the edges of the two LED chip packaging modules 200 to be spliced ​​are all pixels, the two LED chip packaging modules 200 can be spliced ​​first, and then a light-isolating structure can be made at the splicing point. Then, during splicing, affected by factors such as alignment tolerance, the distance between the chip at the outermost edge of one LED chip packaging module 200 (Micro LED chip or Micro IC) and the chip at the outermost edge of another LED chip packaging module 200 (Micro IC or Micro LED chip) may be less than the width of the light-isolating structure. At this time, the spacing between two adjacent Micro LED pixels at the module splicing point will be smaller than the pixel spacing within the LED chip packaging module 200.

[0226] For example, for a display screen with a pixel density of 300ppi (pixels per inch), the pixel pitch can be 80μm. If the size of the Micro LED chip is 10μm and the pitch between the RGB chips is 5μm, it can be inferred that the distance between the red-light-emitting Micro LED chip on the rightmost side of a pixel and the blue-light-emitting Micro LED chip on the leftmost side of the adjacent pixel is 30μm. Therefore, as long as the edges of the two LED chip packaging modules 200 to be spliced ​​do not contain a light-isolating structure and the distance during splicing is less than 40μm, the pitch between two adjacent Micro LED pixels at the module splicing point can be made less than 80μm, and the limit can reach 40μm.

[0227] The embodiment of the present application also provides an electronic device, which includes any one of the display screens or LED chip packaging modules provided in the above embodiments of the present application. In some embodiments, the electronic device may include: a mobile phone, a tablet computer, a smart bracelet, a smart watch, an e-reader, a television, a display, a virtual / mixed / augmented reality device, a smart home device with a display screen (such as: a smart speaker, a smart cat's eye), a household appliance with a display screen (such as: a refrigerator, an air purifier, a washing machine, a water heater, etc.), and a transportation device with a display screen (for example: a vehicle's on-board system, an autonomous driving platform, a driving recorder, etc.).

[0228] In addition, the electronic device provided in the embodiment of the present application may also include other components such as a processor, a memory, a battery, a speaker, an earpiece, a camera, etc., which are not specifically limited here.

[0229] The technical solution provided by the embodiment of the present application has the following beneficial effects:

[0230] First, the technical solution provided by the embodiment of the present application does not use the micro-nano-bump process in the process of manufacturing the LED chip packaging module, and does not need to make a micro bump on the electrode of the Micro LED chip, thereby avoiding the problem of the solder material of the microbump diffusing into the ohmic metal layer and affecting the device characteristics, which is conducive to improving the production yield, and also avoids the problem of the difficulty of the high PPI LED chip packaging process caused by the limitations of the micro-nano-bump process itself. In addition, since the micro-nano-bump process is not used, the total thickness of the pixel is reduced, and the aspect ratio between the total thickness of the pixel and the distance between pixels is reduced, making the volume process of optical or other elements between Micro LED chips or between pixels easier, which is conducive to improving the production yield.

[0231] In addition, compared with the traditional micro-nano bonding process, the technical solution provided by the embodiment of the present application significantly reduces the number of I / O pads on the LED chip packaging module and the driver backplane, so that under the same LED chip packaging module and driver backplane size, the size of each pad can be larger, even much larger than the size of the Micro LED chip, thereby greatly reducing the difficulty of bonding between the LED chip packaging module and the driver backplane, which is conducive to improving the product yield. For example, assuming that each pixel of the LED chip packaging module contains three Micro LED chips, and the spacing between pixels is 0.1mm, if a module contains 100x100 pixels and a total of 10,000 pixels, then the size of the entire module is 10mm x 10mm, and there are 30,000 Micro LED chips in total; in order to make this module, if the traditional micro-nano bonding process is used, since each MicroLED chip contains at least two electrodes, positive and negative, at least 60,000 pads need to be placed in the 10mm x 10mm area, so the maximum area and diameter of each pad will be about 0.00167mm when the fan-shaped packaging design is used. 2The size is very small and the process is very difficult. If the method provided in the embodiment of the present application is adopted, taking the case that the three Micro LED chips in each pixel are controlled by a Micro IC to light up the time or intensity, the DDIC driving the backplane only needs to communicate with the Micro IC for I / O, such as telling each Micro IC to control the color and brightness of the Micro LED chip to light up by scanning, so the LED chip packaging module only needs to set the pad for I / O communication with the DDIC. The signal transmitted by DDIC to Micro IC is programmable and only needs to meet a specific display architecture. For example, the scan line and data line architecture are used to sequentially operate each group of pixels in the LED chip packaging module. At this time, the I / O required by the LED chip packaging module to receive external input signals or currents will only include 100 I / Os corresponding to the scan line, 100 I / Os corresponding to the dataline, and a few necessary clock signals and ground signals. Therefore, the LED chip packaging module can reduce the number of external pads to less than 300, and in extreme cases, it can reach 200 pads, and no more than 100×100×Z pads, where Z is the number of external I / Os for each pixel. It can be seen that in an area of ​​10mm x 10mm, the maximum area and diameter of each pad can reach 0.33mm 2 and 0.577mm, so the size of the external pad of the LED chip packaging module can be much larger than the size of the Micro LED chip, which greatly reduces the difficulty of bonding between the LED chip packaging module and the driver backplane, and even allows bonding to be achieved using a simpler SMT process.

[0232] In addition, since the LED chip packaging module already contains a Micro IC that can drive a small number of Micro LED chips, and the Micro ICs of the Micro LED chips have formed a drivable circuit through RDL, a probe can be used to input a driving signal from the I / O pad of the LED chip packaging module to directly detect the display effect of the LED chip packaging module, so as to select defect-free LED chip packaging modules or those with similar photoelectric characteristics to be combined into a display screen, thereby improving the process yield and utilization rate.

[0233] In addition, the Micro LED chips of the LED chip packaging module are fixed by a transparent packaging layer, and the electrode surfaces of each Micro LED chip are on the same plane, so that the height and tilt angle of all Micro LED chips can be kept consistent, which is beneficial to improving the uniformity of the display screen.

Claims

1. A method for packaging an LED chip, characterized in that: include: Arrange the Micro LED chip and the Micro IC on a first substrate in a separable manner, with the electrodes of the Micro LED chip and the electrodes of the Micro IC facing the first substrate; Coating a transparent encapsulation layer on the surface of the Micro LED chip, the Micro IC and the first substrate; After the transparent encapsulation layer is cured, the first substrate is removed so that the transparent encapsulation layer forms a first plane exposing the electrodes of the Micro LED chip and the electrodes of the Micro IC; Manufacturing RDL on the first plane, wherein the Micro IC is electrically connected to the Micro LED through the RDL; A first pad is formed on the lower surface of the RDL opposite to the transparent encapsulation layer, the first pad is electrically connected to the Micro IC through the RDL, the first pad is used to receive an external driving signal, and the Micro IC is used to control the working state of the Micro LED chip electrically connected thereto according to the external driving signal; Wherein, the method of arranging the Micro LED chip and the Micro IC separably on the first substrate includes: Arrange the plurality of Micro LED chips on the first substrate to form a plurality of pixels, each of the pixels comprising at least one Micro LED chip, and one Micro IC is disposed adjacent to one side of each pixel; After the transparent encapsulation layer is coated on the surface of the Micro LED chip, the Micro IC and the first substrate, the method further includes: Polishing a side of the transparent encapsulation layer away from the first substrate to form an encapsulation plane parallel to the first substrate; A micro-nano structure is manufactured on the packaging plane.

2. The method according to claim 1, characterized in that The RDL electrically connects the MicroLED chip in each pixel to the adjacent Micro IC.

3. The method according to claim 1, characterized in that The method of arranging the Micro LED chips and the Micro IC separably on the first substrate includes: arranging a plurality of the Micro LED chips on the first substrate to form a plurality of pixels, each of the pixels including at least one Micro LED chip, and distributing at least one Micro IC between the plurality of pixels.

4. The method according to claim 3, characterized in that: The RDL electrically connects each of the Micro ICs to the Micro LED chip in at least one of the pixels.

5. The method according to claim 3, characterized in that: Before coating the transparent encapsulation layer on the surface of the Micro LED chip, the Micro IC and the first substrate, the method further includes: manufacturing a light isolation structure on the surface of the first substrate.

6. The method according to claim 5, characterized in that The light isolation structure is arranged between adjacent pixels.

7. The method according to claim 6, characterized in that The light isolation structure is disposed between adjacent MicroLED chips.

8. The method according to claim 1, characterized in that Before coating the transparent encapsulation layer on the surface of the Micro LED chip, the Micro IC and the first substrate, the method further includes: coating a color conversion material on the surface of part or all of the Micro LED chip, wherein the color conversion material is used to convert the color light emitted by the Micro LED chip into other colors.

9. The method according to claim 1, characterized in that: A first adhesive layer is disposed on the surface of the first substrate, and the first adhesive layer is used to detachably place the Micro LED chip and the Micro IC.

10. The method according to claim 1, characterized in that Before the Micro LED chip and the Micro IC are separably arranged on the first substrate, the method further includes: Growing a Micro LED epitaxial wafer structure on the substrate surface; Using a standard semiconductor process to manufacture the epitaxial wafer structure into a plurality of Micro LED chips; Turning the substrate and the Micro LED chip thereon over as a whole so as to be detachably placed on a second substrate; The substrate is removed.

11. The method according to claim 10, characterized in that A second adhesive layer is disposed on the surface of the second substrate, and the second adhesive layer is used for detachably placing the Micro LED chip.

12. The method according to claim 10 or 11, characterized in that: The method of arranging the Micro LED chips and the Micro IC on the first substrate in a separable manner includes: gluing a plurality of the Micro LED chips from the second substrate at one time, placing the gluing Micro LED chips on the first substrate, and gluing at least one Micro IC from the third substrate on which the Micro IC is detachably placed, and placing the gluing Micro IC on the first substrate.

13. A method for packaging an LED chip, characterized in that: include: Arranging the Micro LED chips on the first substrate in a separable manner, with the electrodes of the Micro LED chips facing the first substrate; The plurality of Micro LED chips are arranged on the first substrate to form a plurality of pixels, each of the pixels includes at least one Micro LED chip, and N is a positive integer; Coating a transparent encapsulation layer on the surface of the Micro LED chip and the first substrate; After the transparent encapsulation layer is cured, the first substrate is removed so that the transparent encapsulation layer forms a first plane exposing the electrodes of the Micro LED chip; Making RDL on the first plane, and mounting Micro IC on the lower surface of the RDL facing away from the transparent encapsulation layer, with the electrode surface of the Micro IC facing the RDL, and the Micro IC being electrically connected to the MicroLED through the RDL; A first pad is formed on the lower surface of the RDL, the first pad is electrically connected to the Micro IC through the RDL, the first pad is used to receive an external driving signal, and the Micro IC is used to control the working state of the Micro LED chip electrically connected thereto according to the external driving signal; After the transparent encapsulation layer is coated on the surface of the Micro LED chip and the first substrate, the method further includes: Polishing a side of the transparent encapsulation layer away from the first substrate to form an encapsulation plane parallel to the first substrate; A micro-nano structure is manufactured on the packaging plane.

14. The method according to claim 13, characterized in that The RDL electrically connects each of the Micro ICs to the Micro LED chip in at least one of the pixels.

15. The method according to claim 13, characterized in that The method of coating a transparent encapsulation layer on the surface of the Micro LED chip and the first substrate also includes: making a light isolation structure on the surface of the first substrate.

16. The method according to claim 15, characterized in that The light isolation structure is arranged between adjacent pixels.

17. The method according to claim 15, characterized in that The light isolation structure is disposed between adjacent MicroLED chips.

18. A method for packaging an LED chip, characterized in that: include: Arranging the Micro LED chips on the first substrate in a separable manner, with the electrodes of the Micro LED chips facing the first substrate; The Micro LED chips are arranged on the first substrate to form a plurality of pixels, each of the pixels includes at least one Micro LED chip, and N is a positive integer; Coating a transparent encapsulation layer on the surface of the Micro LED chip and the first substrate; After the transparent encapsulation layer is cured, the first substrate is removed so that the transparent encapsulation layer forms a first plane exposing the electrodes of the Micro LED chip; Fabricating an RDL on the first plane, and fabricating a first pad on a lower surface of the RDL opposite to the transparent encapsulation layer, wherein the first pad is electrically connected to the Micro LED chip through the RDL. The first pad is used to receive an external driving signal, and the external driving signal is used to control the working state of the Micro LED chip electrically connected thereto; After the transparent encapsulation layer is coated on the surface of the Micro LED chip and the first substrate, the method further includes: Polishing a side of the transparent encapsulation layer away from the first substrate to form an encapsulation plane parallel to the first substrate; A micro-nano structure is manufactured on the packaging plane.

19. The method according to claim 18, characterized in that The method of coating a transparent encapsulation layer on the surface of the Micro LED chip and the first substrate also includes: making a light isolation structure on the surface of the first substrate.

20. The method according to claim 19, characterized in that The light isolation structure is arranged between adjacent pixels.

21. The method according to claim 19, characterized in that The light isolation structure is disposed between adjacent MicroLED chips.

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