Miniature light-emitting device and manufacturing method thereof

Abstract

The manufacturing method comprises the steps that a light-emitting array structure comprising a substrate and a plurality of light-emitting chips and a driving array structure comprising a plurality of driving chips are provided, and each driving chip is provided with a bonding area and a non-bonding area and comprises a peripheral electrode arranged on one side of the driving chip in the non-bonding area; forming a protective layer at least covering the peripheral electrode on the side, provided with the peripheral electrode, of the driving chip in the non-bonding area; the light-emitting array structure and the driving array structure are bonded to obtain a bonding structure, a light-emitting chip in the bonding structure is correspondingly connected to a driving chip in a bonding area in a bonding mode, and the substrate is connected to a driving chip in a non-bonding area through a protection layer; forming an underfill layer in a gap between the light emitting array structure and the driving array structure; removing the substrate and exposing the protective layer; and the exposed protective layer is processed to expose the peripheral electrode, so that the problem of underfill residue on the surface of the peripheral electrode in a multi-chip bonding process can be solved, and the reliability and yield of a product are improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor light emitting technology, and in particular to a micro light emitting device and a method for manufacturing the same. Background Art

[0002] Micro-LED (Micro Light Emitting Diode) chip arrays generally refer to chip arrays formed on a single LED (Light Emitting Diode) epitaxial wafer through processes such as photolithography, etching, evaporation, and cutting. The size of Micro-LED chip arrays used in micro-displays is generally a few millimeters to tens of millimeters. Compared with current display devices such as LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Display), Micro-LED display devices have significant advantages such as fast response, high color gamut, high PPI (Pixels per inch), high brightness and low energy consumption. They can be widely used in fields such as AR (Augmented Reality) / VR (Virtual Reality) micro-displays and wearable micro-displays.

[0003] However, the existing manufacturing process of Micro-LED display devices has problems with low product yield and reliability. Summary of the Invention

[0004] The embodiments of the present application provide a micro-light-emitting device and a method for manufacturing the same, so as to improve the manufacturing process of existing Micro-LED display devices, thereby solving the problem of underfill residue on the surface of the peripheral electrode in the multi-chip (DIE) bonding process and improving the reliability and yield of the product.

[0005] An embodiment of the present application provides a method for manufacturing a micro-light-emitting device, which comprises: providing a light-emitting array structure and a driving array structure, wherein the light-emitting array structure comprises a substrate and a plurality of light-emitting chips arranged on one side of the substrate, and the driving array structure comprises a plurality of driving chips, the driving chip having a bonding area and a non-bonding area arranged around the bonding area, and comprising a peripheral electrode, the peripheral electrode being arranged on one side of the driving chip in the non-bonding area; forming a protective layer on the side of the driving chip in the non-bonding area where the peripheral electrode is arranged, the protective layer at least covering the peripheral electrode; bonding the light-emitting array structure to the driving array structure to obtain a bonding structure, wherein the light-emitting chips in the bonding structure are correspondingly bonded to the driving chips in the bonding area, and the substrate in the bonding structure is connected to the driving chips in the non-bonding area through the protective layer; forming a bottom filling layer in the gap between the light-emitting array structure and the driving array structure in the bonding structure; removing the substrate of the light-emitting array structure in the bonding structure to expose the protective layer; processing the protective layer exposed by removing the substrate to expose the peripheral electrodes of the driving chip, and preparing a micro-light-emitting device based on the exposed peripheral electrodes.

[0006] Among them, cutting paths are provided between the multiple driving chips, and the cutting paths are located in the non-bonding areas of the multiple driving chips; and after a bottom filling layer is formed in the gap between the light-emitting array structure and the driving array structure in the bonding structure, the method for manufacturing a micro-light-emitting device also includes: cutting the bonding structure along the cutting paths of the driving array structure in the bonding structure to obtain multiple micro-light-emitting structures, each micro-light-emitting structure including at least one light-emitting chip and at least one driving chip correspondingly bonded together.

[0007] Among them, a micro-light-emitting device is prepared based on the exposed peripheral electrodes, including: setting a micro-light-emitting structure on one side of a circuit board; electrically connecting the peripheral electrodes of the driving chip in the micro-light-emitting structure to the pads of the circuit board to prepare the micro-light-emitting device.

[0008] The protective layer exposed by removing the substrate is processed to expose the peripheral electrodes of the driver chip, which includes: cleaning and removing the protective layer exposed by removing the substrate to expose the peripheral electrodes of the driver chip.

[0009] Among them, the protective layer has a solidified state and a flowable state; the manufacturing method of the micro-light-emitting device also includes: in the process of bonding the light-emitting array structure to the driving array structure, the protective layer is changed from a solidified state to a flowable state, the protective layer in the flowable state is squeezed by the substrate in the light-emitting array structure and adheres to the substrate, and then the protective layer is changed from the flowable state to a solidified state, and the protective layer in the solidified state connects the substrate in the light-emitting array structure and the driving chip in the driving array structure together.

[0010] Among them, a protective layer is formed on the side of the driver chip in the non-bonding area where the peripheral electrode is provided, including: forming a protective layer on the side of the driver array structure where the peripheral electrode is provided, the protective layer completely covers the non-bonding areas of multiple driver chips, and is arranged around the bonding area of ​​each driver chip in the driver array structure to form multiple accommodating areas, each accommodating area corresponds to a driver chip in the driver array structure, and the orthographic projection of each accommodating space on the driver array structure completely overlaps with the bonding area of ​​the corresponding driver chip.

[0011] Among them, the protective layer is located on the side of the driving array structure where the peripheral electrode is provided, and is arranged around the bonding area of ​​each driving chip in the driving array structure to form a plurality of accommodating areas, each accommodating area corresponds to a driving chip in the driving array structure, and the side walls of each accommodating space are provided with a plurality of exhaust channels, and the interior of each accommodating space is connected to a specified position of the edge area of ​​the driving array structure through the plurality of exhaust channels; an underfill layer is formed in the gap between the light-emitting array structure and the driving array structure in the bonding structure, including: performing point underfill at a specified position of the edge area of ​​the driving array structure in the bonding structure, the underfill being filled in the gap between the bonded driving chip and the light-emitting chip through the exhaust channel, and then curing the underfill to form an underfill layer that fills the gap between the bonded light-emitting array structure and the driving array structure.

[0012] Among them, a protective layer is formed on the side of the driver chip where the peripheral electrode is provided in the non-bonding area, including: forming a photoresist layer on the side of the driver chip where the peripheral electrode is provided; exposing and developing the photoresist layer to at least expose the bonding area of ​​the driver chip, and the retained photoresist layer forms a protective layer.

[0013] The driving array structure is a driving wafer; providing a light-emitting array structure includes: providing a light-emitting wafer; and cutting the light-emitting wafer to obtain a plurality of light-emitting array structures.

[0014] An embodiment of the present application further provides a micro light-emitting device, which is manufactured by any of the above-mentioned methods for manufacturing a micro light-emitting device.

[0015] The beneficial effects of the present application are as follows: Compared to the related art where underfill glue covers the peripheral electrode surface of the driver chip, affecting the packaging, the micro-light-emitting device and its manufacturing method provided by the present application form a protective layer that at least covers the peripheral electrodes of the driver chip before the bonding step, thereby reducing the coverage of the peripheral electrode surface of the driver chip by the underfill glue, thereby improving the packaging yield. In addition, by designing the bonding structure obtained after the bonding step, the substrate is connected to the non-bonding area of ​​the driver chip through the protective layer. This can improve the problem of the sidewalls of the light-emitting array structure being wrapped by the underfill glue layer in the bonding structure after underfill, making it difficult to separate the substrate of the light-emitting array structure from the light-emitting chip. This reduces the difficulty of separating the substrate and reduces the damage caused by separating the substrate, thereby improving the substrate separation yield and efficiency.

[0016] Furthermore, compared to the difficulty in completely removing the underfill glue using resin glue, this embodiment effectively isolates the peripheral electrodes of the driver chip from the underfill glue layer formed during the underfill step by providing a protective layer. The material selection for the protective layer is flexible and diverse, and the appropriate material can be selected as needed, making the protective layer easier to completely remove than the underfill glue. This design effectively reduces the adverse effects of residual protective layer on the surface of the peripheral electrodes on subsequent processes, successfully solving the problem of residual underfill glue on the surface of the peripheral electrodes in the multi-chip bonding process, and significantly improving the reliability and yield of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a schematic flow chart of a method for manufacturing a micro-light-emitting device according to an embodiment of the present application;

[0019] Figure 2 1 is a schematic diagram of a top view of the light-emitting wafer provided in an embodiment of the present application;

[0020] Figure 3 This is a schematic diagram of the operation of cutting a light-emitting wafer to obtain a light-emitting array structure provided in an embodiment of the present application;

[0021] Figure 4 is a schematic cross-sectional view of a light-emitting array structure provided in an embodiment of the present application;

[0022] Figure 5 1 is a schematic diagram of a top view of the driver wafer provided in an embodiment of the present application;

[0023] Figure 6 is a schematic cross-sectional view of a drive array structure provided by an embodiment of the present application;

[0024] Figure 7 is a schematic top view of the drive array structure provided in an embodiment of the present application;

[0025] Figure 8 is a schematic diagram of the cross-sectional structure after forming a protective layer provided in an embodiment of the present application;

[0026] Figure 9 This is a schematic diagram of a top view of the structure after forming a protective layer according to an embodiment of the present application;

[0027] Figure 10 Schematic diagram of the cross-sectional structure of the pre-bonded structure provided in an embodiment of the present application;

[0028] Figure 11 is a schematic cross-sectional view of a bonding structure provided in an embodiment of the present application;

[0029] Figure 12 1 is a schematic cross-sectional view of a bonding structure after underfill provided in an embodiment of the present application;

[0030] Figure 13 Schematic diagram of the cross-sectional structure of the bonding structure after the substrate is removed provided in an embodiment of the present application;

[0031] Figure 14 1 is a schematic diagram of the cross-sectional structure of the bonding structure after the protective layer is removed according to an embodiment of the present application;

[0032] Figure 15 Schematic diagram of the cross-sectional structure of the bonding structure after cutting provided in an embodiment of the present application;

[0033] Figure 16 It is a schematic diagram of the cross-sectional structure of the micro light-emitting device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0035] The following is a further detailed description of the embodiments of the present application in conjunction with the accompanying drawings and examples. It is particularly noted that the following examples are only used to illustrate the embodiments of the present application, but do not limit the scope of the embodiments of the present application. Similarly, the following examples are only some embodiments of the embodiments of the present application and not all embodiments. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the embodiments of the present application.

[0036] In the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the described features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise specifically defined.

[0037] In the following description, a second component being connected to a first component may include an embodiment in which the second component is directly connected to the first component, and may also include an embodiment in which the second component is connected to the first component through an additional component such that the second component is not directly connected to the first component.

[0038] In the following description, the second component is connected to the first component, which may include an embodiment in which the second component is directly connected to the first component, and may also include an embodiment in which the second component is connected to the first component through an additional component, so that the second component is not directly connected to the first component.

[0039] When describing the structure of a component, when a layer or region is referred to as being "on" or "above" another layer or region, it can mean that it is directly above the other layer or region, or that other layers or regions are included between it and the other layer or region. Furthermore, if the component is turned over, the layer or region will be "below" or "beneath" the other layer or region. In addition, the features, structures, or characteristics described below can be combined in any suitable manner in one or more embodiments.

[0040] In addition, the directional terms mentioned in the embodiments of the present application, such as [up], [down], [front], [back], [left], [right],

[0041] References to "inside," "outside," and "side" are merely references to the directions in the accompanying drawings. Therefore, the directional terms used are intended to illustrate and facilitate understanding of the embodiments of the present application, and are not intended to limit the embodiments of the present application. In the various figures, similarly structured elements are denoted by the same reference numerals. For clarity, parts in the figures are not drawn to scale. Furthermore, certain related parts may not be shown in the figures.

[0042] Micro-LED display technology miniaturizes and arrays traditional LED structures to form display chips. Using CMOS (Complementary Metal Oxide Semiconductor), each pixel is addressed and driven individually through a bonding process. Bonding, a crucial step in Micro-LED display technology, plays a significant role in product performance.

[0043] Existing Micro-LED micro-displays usually adopt the following structure: the bottom is the driver IC chip (Integrated Circuit Chip, integrated circuit chip), and the top is the Micro-LED chip array sheet. The two are monolithically welded through flip-chip technology, and then go through processes such as underfill, solid crystal, and wire bonding. In order to improve the efficiency of bonding production, the industry has developed a multi-chip bonding process, upgrading from single-chip bonding to multi-chip bonding. However, during the underfill process of the multi-chip bonding structure, the cutting paths and electrodes between adjacent LEDs will be covered by the underfill glue. The underfill glue in this area needs to be removed cleanly so as not to affect the subsequent packaging process. In related technologies, the solution of using a dry etching process to remove the underfill glue in this area has the problem of being unable to completely remove the underfill glue, resulting in a low packaging yield and high mass production costs.

[0044] In response to the above problems, the embodiments of the present application provide a micro-light-emitting device and a method for manufacturing the same. By forming a protective layer that at least covers the peripheral electrodes of the driver chip before the bonding step, the coverage of the peripheral electrode surface of the driver chip by the underfill glue can be reduced during the underfill step. By designing the bonding structure obtained after the bonding step, the substrate is connected to the non-bonding area of ​​the driver chip through the protective layer. This can improve the problem of the sidewalls of the light-emitting array structure being wrapped by the underfill layer in the bonding structure after underfill, which makes it difficult to separate the substrate of the light-emitting array structure from the light-emitting chip. In addition, the material selection of the protective layer is flexible and diverse, and the appropriate material can be selected as needed, so that the protective layer is easier to completely remove than the underfill layer. This design effectively reduces the adverse effects of the residual protective layer on the surface of the peripheral electrode on subsequent processes, successfully solves the problem of residual underfill on the surface of the peripheral electrode in the multi-chip bonding process, and significantly improves the reliability and yield of the product.

[0045] The following is a detailed description with reference to specific embodiments. It should be noted that the embodiments of the present application can be presented in various forms, some of which will be described below.

[0046] See also Figure 1 , Figure 1 : is a schematic diagram of a process for manufacturing a micro-light-emitting device provided in an embodiment of the present application. The specific process of the method for manufacturing a micro-light-emitting device can be as follows:

[0047] Step S11: providing a light-emitting array structure and a driving array structure, wherein the light-emitting array structure comprises a substrate and a plurality of light-emitting chips arranged on one side of the substrate, and the driving array structure comprises a plurality of driving chips, each of which has a bonding region and a non-bonding region arranged around the bonding region, and comprises a peripheral electrode arranged on one side of the driving chip in the non-bonding region.

[0048] In the embodiment, as shown in the figure, Figure 2 The light-emitting array structure 10 can be a light-emitting wafer 100 comprising a plurality of light-emitting chips 11; or, as shown in the figure, Figure 3 The light-emitting array structure 10 can be obtained by cutting the light-emitting wafer 100 comprising a plurality of light-emitting chips 11. The light-emitting chip 11 can be a light-emitting diode chip such as a Micro LED chip or a Mini LED chip. In some examples, providing the light-emitting array structure 10 can comprise providing a light-emitting wafer 100 and cutting the light-emitting wafer 100 to obtain a plurality of light-emitting array structures 10. Figure 3

[0049] In the embodiment, as shown in the figure, Figure 4 The light-emitting array structure 10 can comprise a substrate 12 and a plurality of light-emitting chips 11 arranged on one side of the substrate 12. The substrate 12 can comprise a substrate 121 for supporting a film layer structure thereon, and can be a sapphire substrate, a silicon substrate or a silicon carbide substrate, etc. In some examples, the substrate 121 can specifically be a sapphire substrate.

[0050] Specifically, as shown in the figure, Figure 4 In the light-emitting array structure 10, the substrate 12 can further comprise a buffer layer 122 arranged on one side of the substrate 121, and the plurality of light-emitting chips 11 are arranged on one side of the buffer layer 122 away from the substrate 121. The material of the buffer layer 122 can comprise at least one of a buffer material such as gallium nitride, indium nitride, indium gallium nitride and aluminum indium gallium nitride. In some examples, the buffer layer 122 can specifically be a gallium nitride (GaN) layer.

[0051] In the embodiment, as shown in the figure, Figure 4 In the light-emitting array structure 10, each light-emitting chip 11 can have at least one light-emitting region C1, and can comprise an epitaxial light-emitting stack 111 arranged on one side of the substrate 12. The epitaxial light-emitting stack 111 comprises a first semiconductor layer 1111, a light-emitting layer 1112 and a second semiconductor layer 1113. The first semiconductor layer 1111 is arranged on one side of the substrate 12. The light-emitting layer 1112 and the second semiconductor layer 1113 are located within the light-emitting region C1 and are sequentially arranged on one side of the first semiconductor layer 1111 away from the substrate 12.​

[0052] Specifically, the light-emitting layer 1112 may be a quantum well layer, for example, an indium gallium nitride quantum well layer, or an indium gallium nitride / gallium nitride multi-quantum well layer. The first semiconductor layer 1111 and the second semiconductor layer 1113 may have different polarities. Specifically, the first semiconductor layer 1111 may be one of an N-type semiconductor layer and a P-type semiconductor layer, and the second semiconductor layer 1113 may be the other of an N-type semiconductor layer and a P-type semiconductor layer. The N-type semiconductor layer may be an N-type gallium nitride layer or an N-type gallium arsenide layer, and the P-type semiconductor layer may be a P-type gallium nitride layer or a P-type aluminum gallium nitride layer.

[0053] In some embodiments, as Figure 4 As shown, in the light-emitting array structure 10, each light-emitting chip 11 may further include a non-light-emitting region C2 disposed around each light-emitting region C1. Furthermore, in each light-emitting chip 11, there may be multiple light-emitting regions C1, which may be spaced apart and arranged in an array to form a light-emitting region array. Furthermore, the non-light-emitting region C2 may include a spacing region C21 and a peripheral region C22. The spacing region C21 is a spacing region between the multiple light-emitting regions C1, used to separate each light-emitting region C1 from the other light-emitting regions C1 located around it. The peripheral region C22 is a peripheral region of the multiple light-emitting regions C1, used to provide a common electrode for the pixel.

[0054] Specifically, if Figure 4 As shown, in the light-emitting array structure 10, each light-emitting chip 11 may further include polarity electrodes 115 / 116 (i.e., a first polarity electrode 115 and a second polarity electrode 116). The first polarity electrode 115 and the second polarity electrode 116 are located in the light-emitting region C1 and are disposed on a side of the second semiconductor layer 1113 facing away from the light-emitting layer 1112. The second polarity electrode 116 is located in the non-light-emitting region C2 and is disposed on a side of the first semiconductor layer 1111 facing away from the substrate 12. Furthermore, the height of the second polarity electrode 116 relative to the first semiconductor layer 1111 can be close to or equal to the height of the first polarity electrode 115 relative to the first semiconductor layer 2031 to facilitate subsequent processing steps.

[0055] Furthermore, in the above embodiment in which the non-luminous region C2 includes the spacing region C21 and the peripheral region C22, as shown in FIG. Figure 4 As shown, the second polarity electrode 116 may be specifically located in the peripheral region C22 of the non-light emitting region C1 .

[0056] In some embodiments, as Figure 4As shown, in the light emitting array structure 10, each light emitting chip 11 can further include a current diffusion layer 114 located within the light emitting region C1 and disposed between the first polarity electrode 115 and the second semiconductor layer 1113, and the current diffusion layer 114 can spread the current to the second semiconductor layer 1113 (e.g., a P-type gallium nitride layer), thereby improving the light emitting efficiency of the light emitting layer 1112.

[0057] In particular implementation, the current diffusion layer 114 can be formed by evaporating a multi-layer metal (e.g., titanium Ti, aluminum Al, gold Au, platinum Pt, or nickel Ni, etc.) or a semiconductor oxide (e.g., indium tin oxide ITO or zinc oxide ZnO, etc.) on the surface of the second semiconductor layer 1113 facing away from the light emitting layer 1112.

[0058] In some embodiments, Figure 4 As shown, in the light emitting array structure 10, each light emitting chip 11 can further include a passivation layer 112 covering the epitaxial light emitting stack 111 to effectively prevent the external water and oxygen from eroding the epitaxial light emitting stack 111, thereby improving the product reliability.

[0059] In the above embodiment in which the light emitting chip 11 further includes the current diffusion layer 114, as Figure 4 As shown, the passivation layer 112 can also cover the current diffusion layer 114 to effectively prevent the external water and oxygen from eroding the current diffusion layer 114, thereby improving the product reliability.

[0060] In particular, as Figure 4 As shown, in each light emitting chip 11, the first polarity electrode 115 can include a first electrode layer 1151, a first conductive structure 1152, and a first bonding electrode 1153 sequentially stacked in the direction facing away from the second semiconductor layer 1113, and the second polarity electrode 116 can include a second electrode layer 1161, a second conductive structure 1162, and a second bonding electrode 1163 sequentially stacked in the direction facing away from the first semiconductor layer 1111. In addition, the passivation layer 112 can cover the first electrode layer 1151 and the second electrode layer 1161 to effectively prevent the external water and oxygen from eroding the first electrode layer 1151 and the second electrode layer 1161, thereby improving the product reliability.

[0061] The first bonding electrode 1153 can be specifically disposed on a region corresponding to the first electrode layer 1151 on a side of the passivation layer 112 that is away from the epitaxial light-emitting stack 111, the first electrode layer 1151, and the second electrode layer 1161. The first conductive structure 1152 can be located between the first bonding electrode 1153 and the first electrode layer 1151 and penetrate the film structure (e.g., the passivation layer 112) located between the first bonding electrode 1153 and the first electrode layer 1151. Furthermore, the first conductive structure 1152 can be electrically connected to the first bonding electrode 1153 and the first electrode layer 1151 at opposite ends in the longitudinal direction Z, respectively, thereby achieving electrical connection between the first bonding electrode 1153 and the first electrode layer 1151.

[0062] The second bonding electrode 1163 can be specifically disposed on a region corresponding to the second electrode layer 1161 on a side of the passivation layer 112 that faces away from the epitaxial light-emitting stack 111, the first electrode layer 1151, and the second electrode layer 1161. The second conductive structure 1162 can be located between the second bonding electrode 1163 and the second electrode layer 1161 and penetrate the film structure (e.g., the passivation layer 112) located between the second bonding electrode 1163 and the second electrode layer 1161. Furthermore, the opposite ends of the second conductive structure 1162 in the longitudinal direction Z can be electrically connected to the second bonding electrode 1163 and the second electrode layer 1161, respectively, thereby achieving electrical connection between the second bonding electrode 1163 and the second electrode layer 1161.

[0063] In some specific embodiments, in each light-emitting chip 11, the first semiconductor layer 1111 may be an N-type semiconductor layer, and the second semiconductor layer 1113 may be a P-type semiconductor layer. Accordingly, the first polarity electrode 115 may be a P-type electrode electrically connected to the P-type semiconductor layer, and the second polarity electrode 116 may be an N-type electrode electrically connected to the N-type semiconductor layer, thereby achieving that all pixels in the same light-emitting chip 11 share the same N-type electrode and each have an independent P-type electrode.

[0064] In other specific embodiments, in each light-emitting chip 11, the first semiconductor layer 1111 may be a P-type semiconductor layer, and the second semiconductor layer 1113 may be an N-type semiconductor layer. Accordingly, in the above-mentioned light-emitting chip 11, the first polarity electrode 115 may be an N-type electrode electrically connected to the N-type semiconductor layer, and the second polarity electrode 116 may be a P-type electrode electrically connected to the P-type semiconductor layer, thereby achieving that all pixels in the same light-emitting chip 10 share the same P-type electrode and each have an independent N-type electrode.

[0065] In some examples, in each light emitting chip 11 , the second polarity electrode 116 may be ring-shaped, and its orthographic projection on the first semiconductor layer 1111 may surround the orthographic projections of all second electrodes 115 on the first semiconductor layer 1111 to reduce the contact resistance of the second polarity electrode 116 .

[0066] In some examples, the material of the first electrode layer 1151 may include at least one of titanium (Ti), gold (Au), platinum (Pt), nickel (Ni), and aluminum (Al). The material of the second electrode layer 1151 may include at least one of titanium (Ti), gold (Au), platinum (Pt), nickel (Ni), and aluminum (Al). In a specific implementation, the first electrode layer 1151 and the second electrode layer 1161 may be made of the same material and may be formed simultaneously.

[0067] In some examples, the material of the first conductive structure 1052 may include at least one of titanium (Ti), gold (Au), platinum (Pt), nickel (Ni), and aluminum (Al), and the material of the second conductive structure 1062 may include at least one of titanium (Ti), gold (Au), platinum (Pt), nickel (Ni), and aluminum (Al). In a specific implementation, the first conductive structure 1052 and the second conductive structure 1062 may be made of the same material and may be formed simultaneously.

[0068] In some examples, the material of the first bonding electrode 1153 may include at least one of metal materials such as gold (Au), indium (In), tin (Sn), and copper (Cu), and the material of the second bonding electrode 1163 may include at least one of metal materials such as gold (Au), indium (In), tin (Sn), and copper (Cu). In a specific implementation, the first bonding electrode 1153 and the second bonding electrode 1163 may be made of the same material and may be formed simultaneously.

[0069] In some examples, the material of the passivation layer 112 may include at least one of insulating materials such as silicon oxide, silicon nitride, and aluminum oxide.

[0070] In this embodiment, if Figure 5 As shown, the driver array structure 20 may be a driver wafer 200 including a plurality of driver chips 21, or may be obtained by dicing the driver wafer 200 including the plurality of driver chips 21. In some examples, providing the driver array structure 20 may include: providing a driver wafer 200, and dicing the driver wafer 200 to obtain a plurality of driver array structures 20.

[0071] The driver chip 21 may be an IC chip (Integrated Circuit Chip), for example, a CMOS (Complementary Metal Oxide Semiconductor) driver chip or a TFT (Thin Film Transistor) driver chip.

[0072] In this embodiment, if Figure 6 As shown, in the driving array structure 20, each driving chip 21 may include a peripheral electrode 210, a driving circuit layer 211 and driving electrodes 212 / 213 (i.e., a first driving electrode 212 and a second driving electrode 213), the driving electrodes 212 / 213 are located in the bonding area C3 of the driving chip 21, and the driving circuit layer 211 includes a driving circuit 2111, the peripheral electrode 210 and the driving electrode 212 / 213 are arranged on the same side of the driving circuit layer 211, and are both electrically connected to the driving circuit 2111, so that the peripheral electrode 210 inputs an electrical signal to the driving circuit 2111, thereby realizing control of the light-emitting chip 11. The driving electrodes 212 / 213 are used to bond with the polarity electrodes 115 / 116 (i.e., the first polarity electrode 115 and the second polarity electrode 116) of the light-emitting chip 11 in the light-emitting array structure 10, and the driving electrodes 212 / 213 can correspond one-to-one with the polarity electrodes 115 / 116 of the light-emitting chip 11 in the light-emitting array chip 10. The peripheral electrodes 210 can serve as input / output pads for the driver chip 21 and are used to electrically connect to a circuit board (e.g., a flexible circuit board) so that an external power supply can provide an operating voltage to the driver chip 21 through the circuit board.

[0073] Specifically, if Figure 6 As shown, in each driver chip 21, the driver circuit layer 211 may further include a substrate 2112, and the driver circuit 2111 may be disposed on one side of the substrate 2112, and the driver electrodes 212 / 213 and the peripheral electrodes 210 may be disposed on a side of the driver circuit 2111 facing away from the substrate 2112. Furthermore, the substrates 2112 of all driver chips 21 in the driver array structure 20 may be connected into an integrated structure.

[0074] In some examples, the drive electrodes 211 / 212 may be made of a conductive material such as titanium (Ti), aluminum (Al), gold (Au), platinum (Pt), and / or nickel (Ni). The peripheral electrodes 210 may be made of a conductive material such as titanium (Ti), aluminum (Al), gold (Au), platinum (Pt), and / or nickel (Ni). Furthermore, in a specific implementation, the drive electrodes 211 / 212 and the peripheral electrodes 210 may be made of the same material and may be formed simultaneously.

[0075] In some embodiments, as Figure 6 and Figure 7 As shown, in the above-mentioned driving array structure 20 , cutting lanes 22 may be provided between the multiple driving chips 21 included in the driving array structure 20 . The cutting lanes 22 are located in the non-bonding area C4 of the multiple driving chips 21 and are used to cut the driving array structure 20 .

[0076] Specifically, if Figure 6 and Figure 7 As shown, in the above-mentioned driving array structure 20, the multiple driving chips 21 included in the driving array structure 20 can be connected to each other and can be arranged in an array to form a driving chip array, and a cutting path 22 can be provided between two adjacent driving chips 21 in the driving array structure 20.

[0077] Furthermore, during implementation, the width, depth, or height of the dicing lanes 22 can be optimized based on the size and material properties of the driver chip 21 to minimize the impact on chip performance during the dicing process. Furthermore, the layout of the dicing lanes 22 can be adjusted based on the ultimate application of the driver array structure 20. In some cases, the dicing lanes 22 can be designed as straight or curved lines to accommodate specific circuit designs or packaging requirements, thereby enabling the driver array structure 20 to better adapt to the needs of various display devices.

[0078] Step S12: forming a protection layer on the side of the driver chip provided with the peripheral electrode in the non-bonding area, wherein the protection layer at least covers the peripheral electrode.

[0079] The cross-sectional structure diagram after step S12 is completed can be as follows: Figure 8 and Figure 9 shown.

[0080] In this embodiment, if Figure 8 and Figure 9 As shown, the protective layer 30 covers at least the peripheral electrodes 210 of the driver chips 21. Specifically, the protective layer 30 can completely cover the sidewalls of the peripheral electrodes 210 of each driver chip 21 in the driver array structure 20, as well as the surface of the peripheral electrodes 210 of each driver chip 21 in the driver array structure 20 that faces away from the driver circuit layer 211. This can alleviate the problem of underfill glue covering the surface of the peripheral electrodes 210 of the driver chips 21 in the subsequent underfill process, affecting the packaging process, thereby improving the packaging yield.

[0081] In this embodiment, if Figure 8 and Figure 9As shown, the protective layer 30 does not cover the surface (i.e., the upper surface) of the driving electrodes 212 / 213 of the driving chip 21 away from the driving circuit layer 211, so as to ensure that in the subsequent bonding process, the driving electrodes 212 / 213 of the driving chip 21 can be bonded to the polarity electrodes 115 / 116 of the light-emitting chip 11.

[0082] Specifically, if Figure 8 and Figure 9 As shown, the protective layer 30 may not cover the bonding area C3 of the driver chip 21 at all, so that the protective layer 30 completely avoids the bonding area C3 of the driver chip 21, thereby reducing the adverse effect of the protective layer 30 on the bonding strength between the light emitting chip 11 and the driver chip 21.

[0083] In some embodiments, as Figure 8 and Figure 9 As shown, the above-mentioned step S12 may specifically include: forming a protective layer 30 on the side of the above-mentioned driving array structure 20 where the peripheral electrode 210 is provided, and the protective layer 30 may completely cover the non-bonding area C4 of the above-mentioned multiple driving chips 21 included in the above-mentioned driving array structure 20, and may be arranged around the bonding area C3 of each driving chip 21 in the above-mentioned driving array structure 20. For example, it may be arranged around the bonding area C3 of each driving chip 21 in the above-mentioned driving array structure 20 to form a plurality of accommodating spaces. Each accommodating space corresponds to a driving chip 21 in the above-mentioned driving array structure 20, and the orthographic projection of each accommodating space on the above-mentioned driving array structure 20 may completely cover the bonding area C1 of the corresponding driving chip 21. Specifically, the orthographic projection of each accommodating space on the above-mentioned driving array structure 20 may completely overlap with the bonding area C1 of the corresponding driving chip 21.

[0084] In this way, not only can the problem of the underfill glue covering the surface of the peripheral electrode 210 of the driver chip 21 in the subsequent underfill process affecting the packaging be effectively improved, thereby improving the packaging yield, but it can also ensure that in the bonding structure formed in the subsequent step S13, the substrate 12 of the light-emitting array structure 10 and the protective layer 30 have a larger contact area, thereby ensuring the stability of the connection between the substrate 12 of the light-emitting array structure 10 and the driver array structure 20 through the protective layer 30 in the bonding structure.

[0085] In addition, by setting the orthographic projection of each accommodating space on the above-mentioned driving array structure 20 to completely overlap with the bonding area C1 of its corresponding driving chip 21, it can be ensured that in the bonding structure formed in the subsequent step S13, there is no spacing area between the protective layer 30 and the side wall of the substrate 12 of the light-emitting array structure 10. Therefore, in the subsequent underfill process, the underfill glue can be effectively prevented from filling into the spacing area between the protective layer 30 and the side wall of the substrate 12, thereby improving the problem that the side wall of the light-emitting array structure 10 is wrapped by the underfill glue, making it difficult to separate the substrate 12 from the bonding structure. Therefore, this setting can reduce the difficulty of separating the substrate 12 and reduce the damage caused by separating the substrate 12, thereby improving the separation yield and efficiency of the substrate 12.

[0086] Specifically, if Figure 8 and Figure 9 As shown, for each accommodating space enclosed by the protective layer 30 on the side of the driving array structure 20 where the peripheral electrode 210 is provided, a plurality of exhaust channels 31 (for example, two exhaust channels 31) can be opened on the side wall of the accommodating space, and the interior of the accommodating space can be connected to the designated position of the edge area of ​​the driving array structure 20 through the plurality of exhaust channels 31. In this way, in the subsequent underfill process, the plurality of exhaust channels 31 can serve as flow channels for the underfill glue, ensuring that the underfill glue can be filled into the interior of the accommodating space through the plurality of exhaust channels 31.

[0087] In some examples, for each accommodation space enclosed by the protective layer 30 on the side of the driving array structure 20 where the peripheral electrode 210 is provided, the exhaust channel 31 opened on the side wall of the accommodation space can be specifically a through groove, which connects the inside and outside of the accommodation space. Specifically, the depth direction of the through groove can be perpendicular to the driving structure array 20, and the groove can penetrate the protective layer 30 along its depth direction.

[0088] In some embodiments, as Figure 8 and Figure 9 As shown, the above step S12 may include: forming a protective film layer on the side of the driving chip 21 where the peripheral electrode 210 is provided, and then patterning the protective film layer to form a patterned protective film layer. The above protective layer 30 is the patterned protective film layer.

[0089] Specifically, the patterned protective film layer covers at least the peripheral electrodes 210 of the driver chip 21, thereby improving the packaging process and improving the packaging yield. Furthermore, the patterned protective film layer exposes at least the driver electrodes 212 / 213 of the driver chip 21. For example, the bonding area C3 of the driver chip 21 can be completely exposed to ensure that the driver electrodes 212 / 213 of the driver chip 21 can be bonded to the polarity electrodes 115 / 116 of the light-emitting chip 11 during the subsequent bonding process.

[0090] In some specific embodiments, Figure 8 and Figure 9 As shown, the material of the protective layer 30 may be photoresist. Accordingly, the protective layer 30 may be prepared by a photolithography process. Specifically, the step S12 may include:

[0091] Step S121 . Form a photoresist layer on the side of the driver chip 21 where the peripheral electrode 210 is provided.

[0092] Specifically, a photoresist can be applied to one side of the driver chip 21 by spin coating, spray coating, roller coating, or screen printing to form a layer of photoresist, namely a photoresist layer. The photoresist layer covers the bonding area C3 and non-bonding area C4 of the driver chip 21. Specifically, the photoresist layer can completely cover the surface of one side of each driver chip 21 where the peripheral electrode 210 is provided.

[0093] Furthermore, during implementation, the surface of the driver chip 21 on the side where the peripheral electrodes 210 are provided can be cleaned first to remove impurities attached to the surface of the driver chip 21 on the side where the peripheral electrodes 210 are provided. After cleaning, a photoresist layer is formed on the side where the peripheral electrodes 210 are provided to ensure that the photoresist layer uniformly and densely covers the surface of the driver chip 21 on the side where the peripheral electrodes 210 are provided.

[0094] Step S122 . Expose and develop the photoresist layer to expose at least the bonding area C3 of the driver chip 21 , and the remaining photoresist layer forms a protective layer 30 .

[0095] Specifically, the photoresist layer can be exposed and developed to partially or completely remove the photoresist layer covering the bonding area C3 of the driver chip 21, and partially or completely remove the photoresist layer covering the non-bonding area C4 of the driver chip 21. After the exposure and development are completed, the retained photoresist layer forms the above-mentioned protective layer 30.

[0096] Furthermore, it should be noted that the aforementioned partial or complete removal of the photoresist layer covering the bonding area C3 of the driver chip 21 needs to at least include: removing the photoresist layer covering the driving electrodes 212 / 213 of the driver chip 21 to ensure that, in the subsequent bonding process, the driving electrodes 212 / 213 of the driver chip 21 can be bonded to the polarity electrodes 115 / 116 of the light-emitting chip 11. The aforementioned partial or complete removal of the photoresist layer covering the non-bonding area C4 of the driver chip 21 needs to at least include: retaining the photoresist layer covering the peripheral electrodes 210 of the driver chip 21 to improve the problem of underfill glue covering the surface of the peripheral electrodes 210 of the driver chip 21 in the subsequent underfill process, which affects the packaging process, thereby improving the packaging yield.

[0097] Step S13: Bonding the light emitting array structure to the driving array structure to obtain a bonding structure, wherein the light emitting chip in the bonding structure is bonded to the driving chip in the bonding area, and the substrate in the bonding structure is connected to the driving chip in the non-bonding area through the protective layer.

[0098] The cross-sectional structure diagram after step S13 is completed can be as follows: Figure 11 shown.

[0099] Specifically, if Figure 11 As shown, the polarity electrodes 115 / 116 of each light-emitting chip 11 in the light-emitting array structure 10 can be bonded to the driving electrodes 212 / 213 of the corresponding driver chip 21 in the driver array structure 30, thereby achieving the bonding of the light-emitting array structure 10 to the driver array structure 20. Moreover, after the light-emitting array structure 10 and the driver array structure 20 are bonded, the polarity electrodes 115 / 116 of each light-emitting chip 11 in the light-emitting array structure 10 are electrically connected to the driving electrodes 212 / 213 of the corresponding driver chip 21 in the driver array structure 30, thereby enabling the driving circuit in the driver chip 21 to provide a driving signal to the light-emitting chip 11 through the driving electrodes 212 / 213 and the polarity electrodes 115 / 116, thereby driving the light-emitting chip 21 to emit light.

[0100] In some embodiments, as Figure 11 As shown, in the above bonding structure, the orthographic projection of each light-emitting chip 11 on the driving array structure 20 can completely overlap with the bonding area C3 of its corresponding driving chip 21. In addition, in the above bonding structure, the protective layer 30 is located on the side of the driving array structure 20 where the peripheral electrode 210 is provided, and can be arranged around the bonding area C3 of each driving chip 21 in the driving array structure 20 to form a plurality of accommodating areas, wherein each accommodating area corresponds to a driving chip 21 in the driving array structure 20, and the orthographic projection of each accommodating space on the driving array structure 20 can completely overlap with the bonding area C3 of its corresponding driving chip 21.

[0101] Specifically, in the above-mentioned bonding structure, the protective layer 30 is located in the portion between the bonding areas C3 of the above-mentioned multiple driving chips 21 included in the driving array structure 20, and the surface facing away from the driving array structure 20 can be located at the same horizontal plane as the surface of the substrate 12 included in the light-emitting array structure 10 facing the driving array structure 20, and this portion of the protective layer 30 can completely cover the area of ​​the surface of the substrate 12 facing the driving array structure 20 that is not covered by the light-emitting chip 11.

[0102] In the above-mentioned bonding structure, the protective layer 31 is located in the portion surrounding the bonding area C3 of the above-mentioned multiple driving chips 21 included in the driving array structure 20, and the height of the surface facing away from the driving array structure 20 relative to the driving array structure 20 can be greater than or equal to the height of the surface of the substrate 12 included in the light-emitting array structure 10 facing the driving array structure 20 relative to the driving array structure 20.

[0103] In this way, in the subsequent underfill process, the underfill glue can be effectively prevented from filling the side wall surface of the substrate 12 and the surface of the substrate 12 facing the driving array structure 20, thereby improving the problem that the side wall of the light-emitting array structure 10 is wrapped by the underfill glue, making it difficult to separate the substrate 12 from the bonding structure. Therefore, the difficulty of separating the substrate 12 can be reduced, and the damage caused by separating the substrate 12 can be reduced, thereby improving the separation yield and efficiency of the substrate 12.

[0104] In some embodiments, as Figure 11 As shown, the protective layer 30 can have a solidified state and a flowable state. Furthermore, the method for manufacturing the micro-light-emitting device can further include: during the bonding process between the light-emitting array structure 10 and the driver array structure 20, the protective layer 30 is transformed from a solidified state to a flowable state, wherein the protective layer 30 in the flowable state is pressed against the substrate 12 in the light-emitting array structure 10 and adheres to the substrate 12; and then the protective layer 30 is transformed from a flowable state to a solidified state, wherein the solidified protective layer 30 connects the substrate 12 in the light-emitting array structure 10 and the driver chip 21 in the driver array structure 20. The protective layer 30 can be made of a colloid and can be switched between a flowable state and a solidified state.

[0105] Specifically, during the bonding process of the light-emitting array structure 10 and the driving array structure 20, a portion of the protective layer 30 in a flowable state can be squeezed by the substrate 12 in the light-emitting array structure 10 and enter the edge area of ​​the light-emitting chip 11 in the light-emitting array structure 10. In this way, after the protective layer 30 is transformed from a flowable state to a solidified state, the protective layer 30 in a solidified state can not only connect the substrate 12 and the driving chip 21 in the driving array structure 20, but also connect the edge area of ​​the light-emitting chip 11 and the driving chip 21 in the driving array structure 20.

[0106] Furthermore, during specific implementation, in the above-mentioned step S12, when forming the protective layer 30, the size of the protective layer 30 formed needs to take into account: the gap between the light-emitting array structure 10 and the driving array structure 20 corresponding to the non-bonding area C4 position after the light-emitting array structure 10 and the driving array structure 20 are bonded; and the overflow size of the protective layer 30 in a flowable state during the bonding process between the light-emitting array structure 10 and the driving array structure 20. In this way, it is ensured that after the light-emitting array structure 10 and the driving array structure 20 are bonded, the solidified protective layer 30 just fills the gap between the light-emitting array structure 10 and the driving array structure 20 corresponding to the non-bonding area C4 position, and does not overflow into the bonding area C3. At the same time, it is also necessary to reserve an exhaust channel 31 for the convection of the underfill glue on the protective layer 30 to facilitate the execution of the subsequent underfill process steps.

[0107] In some specific embodiments, the above step S13 may specifically include:

[0108] Step S131: Align each light emitting chip 11 in the light emitting array structure 10 with the corresponding driver chip 21 in the driver array structure 20, and attach the substrate 12 in the light emitting array structure 10 to the protective layer 30 to obtain a pre-bonded structure (such as Figure 10 shown);

[0109] Step S132: The protective layer 30 in the pre-bonded structure is transformed from a solidified state to a flowable state, and a bonding pressure is applied to the light emitting array structure 10 and / or the driving array structure 20 in the pre-bonded structure. Under the action of the bonding pressure, the protective layer 30 in the flowable state is squeezed by the substrate 12 in the light emitting array structure 10 and is pressed against the substrate 12. Under the action of the bonding pressure, each light emitting chip 11 in the light emitting array structure 10 is bonded to the corresponding driving chip 21 in the driving array structure 20. Then, the protective layer 30 is transformed from a flowable state to a solidified state. The solidified protective layer 30 connects the substrate 12 in the light emitting array structure 10 and the driving chip 21 in the driving array structure 20 together, thereby obtaining a bonding structure (such as Figure 11 shown).

[0110] Specifically, if Figure 10 As shown, in the above-mentioned pre-bonded structure, the thickness of the protective layer 30 can be greater than the sum of the thickness of the driving circuit layer in the driving array structure 20 and the thickness of the light-emitting chip 11 in the light-emitting array structure 10, thereby ensuring that after the protective layer 30 in the pre-bonded structure is transformed from a solidified state to a flowable state, the protective layer 30 in the flowable state can be squeezed by the substrate 12 in the light-emitting array structure 10 under the action of the bonding pressure and adhered to the substrate 12.

[0111] Moreover, in a specific implementation, the thickness of the protective layer 30 formed in the above step S12 can be controlled to be greater than the sum of the thickness of the driving circuit layer in the driving array structure 20 and the thickness of the light-emitting chip 11 in the light-emitting array structure 10, thereby achieving in the above pre-bonded structure that the thickness of the protective layer 30 is greater than the sum of the thickness of the driving circuit layer in the driving array structure 20 and the thickness of the light-emitting chip 11 in the light-emitting array structure 10.

[0112] It should be noted that compared with the die-to-die bonding method in the related art in which a single light-emitting chip and a single driver chip are bonded, the multi-chip die bonding method in this embodiment bonds a light-emitting array structure 10 including multiple light-emitting chips 11 to a driver array structure 20 including multiple driver chips 21. The bonding of multiple light-emitting chips 11 to the multiple driver chips 21 included in the driver array structure 20 can be achieved through a single multi-chip bonding process, thereby having higher bonding efficiency and being more conducive to shortening the production cycle.

[0113] Step S14: forming an underfill layer in the gap between the light emitting array structure and the driving array structure in the bonding structure.

[0114] The cross-sectional structure diagram after step S14 is completed can be as follows: Figure 12 shown.

[0115] Specifically, if Figure 12 As shown, a bottom filling method can be used to fill the gap between the light-emitting array structure 10 and the driving array structure 20 in the bonding structure with a colloid, and solidify it to obtain a bottom filling layer 40, wherein the bottom filling layer 40 can completely fill the gap between the light-emitting array structure 10 and the driving array structure 20 in the bonding structure to protect the bonding solder joints between the light-emitting array structure 10 and the driving array structure 20 from the influence of moisture and strengthen the connection between the light-emitting array structure 10 and the driving array structure 20, thereby improving the overall preparation yield.

[0116] In some specific embodiments, Figure 11 As shown, in the bonding structure formed in the above step S13, the protective layer 30 can be located on the side of the driving array structure 20 where the peripheral electrode 210 is provided, and is arranged around the bonding area C3 of each driving chip 21 in the driving array structure 20 to form a plurality of accommodating areas, wherein each accommodating area corresponds to a driving chip 21 in the driving array structure 20, and the side walls of each accommodating space are provided with a plurality of exhaust channels, and the interior of each accommodating space is connected to a designated position of the edge area of ​​the driving array structure 20 through the plurality of exhaust channels.

[0117] Accordingly, if Figure 12As shown, the above-mentioned step S14 can specifically include: performing underfilling at the above-mentioned designated position of the edge area of ​​the driving array structure 20 in the bonding structure, the underfill is filled in the gap between the bonded driving chip 21 and the light-emitting chip 11 through the above-mentioned exhaust channel 31, and then the underfill is cured to form the above-mentioned underfill layer 40 that fills the gap between the bonded light-emitting array structure 10 and the driving array structure 20.

[0118] The underfill (ie, the material of the underfill layer 40 ) may be epoxy resin glue.

[0119] Step S15: removing the substrate of the light emitting array structure in the bonding structure to expose the protective layer.

[0120] The cross-sectional structure diagram after step S15 is completed can be as follows: Figure 13 shown.

[0121] Specifically, if Figure 12 and Figure 13 As shown, a laser lift-off process can be used to remove the substrate 12 of the light emitting array structure 10 in the bonding structure, thereby exposing the surface where the protective layer 30 in the bonding structure contacts the substrate 12, thereby facilitating the smooth removal of the protective layer 30 in subsequent processes.

[0122] Moreover, in the above embodiment in which the base 12 of the above-mentioned light-emitting array structure 10 includes a substrate 121 and a buffer layer 122, a laser lift-off process can be first used to remove the substrate 121 of the light-emitting array structure 10 in the bonding structure, and then the buffer layer 122 of the light-emitting array structure 10 in the bonding structure can be decomposed and removed, thereby completing the removal of the base 12 of the light-emitting array structure 10 in the bonding structure.

[0123] It should be noted that, compared to the prior art multi-chip bonding structure, during the underfill process, the underfill glue will penetrate into the gaps between adjacent light-emitting chips, covering the cutting paths of the driver array structure and the peripheral electrodes of the driver chip. Furthermore, due to the strong viscosity of the underfill glue, after curing, the substrate of the light-emitting array structure and the driver array structure will be tightly connected, making it difficult to separate the substrate of the light-emitting array structure from the light-emitting chips, thereby affecting the substrate separation yield and efficiency. In this embodiment, by designing the bonding structure obtained by the bonding step, the substrate 12 is connected to the non-bonding area C4 of the driver chip 21 through the protective layer 30. This can effectively reduce the underfill glue from entering the gaps between adjacent light-emitting chips 11, reduce the bonding strength of the underfill glue to the substrate 12 after curing, thereby reducing the difficulty of separating the substrate 12 from the light-emitting chips 11 in the light-emitting array structure 10, and significantly improve the substrate 12 separation yield and efficiency.

[0124] Furthermore, in this embodiment, the material selection for the protective layer 30 is highly flexible, and a suitable material can be selected based on actual needs. Thus, the adhesion of the protective layer 30 to the substrate 12 is somewhat weaker than that of the underfill, thereby effectively reducing the difficulty of separating the substrate 12 from the light-emitting chips 11 in the light-emitting array structure 10.

[0125] In some examples, the material of the protection layer 30 may be a specific colloid having a certain viscosity, but the viscosity is lower than that of the underfill.

[0126] Step S16: removing the protective layer exposed from the substrate to expose the peripheral electrodes of the driver chip, and preparing a micro light-emitting device based on the exposed peripheral electrodes.

[0127] The cross-sectional structure diagram after step S16 is completed can be as follows: Figure 14 or Figure 15 shown.

[0128] In this embodiment, if Figure 14 or Figure 15 As shown, the above step S16 may specifically include:

[0129] Step S161 : removing the protective layer 30 exposed by the substrate 12 to expose the peripheral electrodes 210 of the driving chip 21 .

[0130] Step S162 : preparing a micro light-emitting device based on the exposed peripheral electrode 210 .

[0131] Specifically, if Figures 13 to 15 As shown, the above step S161 may include: cleaning and removing the protective layer 30 exposed by removing the substrate 12 to expose the peripheral electrodes 210 of the driver chip 21. For example, a cleaning solution may be used to clean and remove the protective layer 30 exposed by removing the substrate 12 to expose the peripheral electrodes 210 of the driver chip 21.

[0132] The cleaning liquid can be an organic solvent such as acetone or isopropyl alcohol. It is understood that the protective layer 30 can be completely dissolved in the cleaning liquid, and the combined structure (such as Figure 13 The other structures except the protective layer 30 in the cleaning solution (as shown in the figure) (for example, the light emitting array structure 10, the driving array structure 20 and the bottom filling layer 40 after the substrate 12 is peeled off) are insoluble in the cleaning liquid and do not react with the cleaning liquid. Therefore, the protective layer 30 can be removed while reducing damage to other structures.

[0133] In some examples, the combined structure obtained after step S15 is completed may be cleaned multiple times (for example, three times) with a cleaning solution to completely remove the protective layer 30 in the combined structure.

[0134] Specifically, in the above embodiment where the material of the protective layer 30 is photoresist, the cleaning and removal process of the protective layer 30 may specifically include: using acetone, isopropyl alcohol and pure water in sequence to clean and remove the exposed protective layer 40, so that the peripheral electrode 210 originally covered by the protective layer 30 is exposed.

[0135] It should be noted that compared to the problem of difficulty in completely removing the underfill covering the peripheral electrodes of the driver chip in the related art, this embodiment effectively isolates the peripheral electrodes of the driver chip from the underfill layer formed in the underfill step by providing a protective layer. The material selection of the protective layer is flexible and diverse, and suitable materials can be selected according to needs, making the protective layer easier to completely remove than the underfill. This design effectively reduces the adverse effects of the residual protective layer on the surface of the peripheral electrode on subsequent processes, successfully solves the problem of residual underfill on the surface of the peripheral electrode in the multi-chip bonding process, and significantly improves the reliability and yield of the product.

[0136] In the above embodiment, after the above step S14, the above method for manufacturing the micro-light emitting device may further include:

[0137] Step S17: cutting the bonding structure to obtain a plurality of micro-light emitting structures 300, each micro-light emitting structure 300 includes at least one light emitting chip 11 and at least one driving chip 21 (such as Figure 15 shown).

[0138] Specifically, in the above embodiment in which a cutting path 22 is provided between the above-mentioned multiple driving chips 21 included in the above-mentioned driving array structure 20, and the cutting path 22 is located in the non-bonding area C4 of the multiple driving chips 21, the above-mentioned step S17 may include: cutting the bonding structure along the cutting path 22 of the driving array structure 20 in the bonding structure to obtain a plurality of micro-light-emitting structures 300, each micro-light-emitting structure 300 including at least one light-emitting chip 11 and at least one driving chip 21 correspondingly bonded and connected.

[0139] Furthermore, during specific implementation, the above step S17 may be performed before the above step S161 or after the above step S161.

[0140] It should be noted that, compared with the solution in which the above-mentioned step S17 is performed before the above-mentioned step S161, the solution in this embodiment in which the above-mentioned step S17 is performed after the above-mentioned step S161 can effectively reduce the adverse effects of the viscosity of the protective layer 30 on the cutting effect because the protective layer 30 in the bonding structure is removed first.

[0141] In some embodiments, as Figure 16 As shown, the above step S162 may be performed after the above step S17, and the above step S162 may specifically include:

[0142] Step S1 - 1 : disposing the micro-light emitting structure 300 on one side of the circuit board 50 .

[0143] Specifically, after the peripheral electrodes 210 of the driver chip 21 are exposed and the micro-light emitting structures 300 are cut, the micro-light emitting structures 300 can be bonded to the surface of the circuit board 50. In some examples, the circuit board 50 can be a flexible printed circuit (FPC).

[0144] Step S1 - 2 : electrically connecting the peripheral electrode 210 of the driving chip 21 in the micro-light emitting structure 300 to the pad 51 of the circuit board 50 to obtain a micro-light emitting device.

[0145] Specifically, the peripheral electrodes 210 of the driver chip 21 in the micro-light-emitting structure 300 can be electrically connected to the pads 51 of the circuit board 50 via the conductive connection component 60 to produce a micro-light-emitting device, thereby facilitating an external power supply to provide an operating voltage to the micro-light-emitting structure 300 via the circuit board 50. The conductive connection component 60 can be a bonding wire or anisotropic conductive film (ACF).

[0146] In some specific embodiments, after step S1 - 2 , the method for manufacturing the micro light-emitting device may further include: forming a packaging adhesive layer 70 , where the packaging adhesive layer 70 covers the micro light-emitting structure 300 and the circuit board 50 of the micro light-emitting device.

[0147] Specifically, after the peripheral electrode 210 of the driving chip 21 in the micro-light-emitting structure 300 is electrically connected to the pad 51 of the circuit board 50 to prepare a micro-light-emitting device, an encapsulation adhesive layer 70 can be formed on the side of the circuit board 50 where the micro-light-emitting structure 300 is provided. The encapsulation adhesive layer 70 can cover the micro-light-emitting structure 300, the conductive connection component 60 and the pad 51 of the circuit board 50 to protect the micro-light-emitting structure 300, the conductive connection component 60 and the pad 51 of the circuit board 50, thereby improving the reliability of the product.

[0148] In some examples, the material of the packaging adhesive layer 70 can be packaging adhesive such as silicone, epoxy, or rubber.

[0149] As can be seen from the above, the manufacturing method of the micro-light-emitting device provided in the embodiment of the present application is through providing a light-emitting array structure and a driving array structure, wherein the light-emitting array structure includes a substrate and a plurality of light-emitting chips arranged on one side of the substrate, the driving array structure includes a plurality of driving chips, the driving chip has a bonding area and a non-bonding area arranged around the bonding area, and includes a peripheral electrode, the peripheral electrode is arranged on one side of the driving chip in the bonding area, and then a protective layer is formed on the side of the driving chip in the non-bonding area where the peripheral electrode is provided, the protective layer at least covers the peripheral electrode, and the light-emitting array structure is bonded to the driving array structure to obtain a bonding structure, the light-emitting chip in the bonding structure is correspondingly bonded to the driving chip in the bonding area, and the substrate in the bonding structure is connected to the driving chip in the non-bonding area through the protective layer, and then a bottom filling layer is formed in the gap between the light-emitting array structure and the driving array structure in the bonding structure, and the substrate of the light-emitting array structure in the bonding structure is removed to expose the protective layer, and then the protective layer exposed by removing the substrate is processed to expose the peripheral electrode of the driving chip. Thus, by forming a protective layer that at least covers the peripheral electrodes of the driver chip before the bonding step, the underfill glue can be prevented from covering the peripheral electrode surface of the driver chip during the underfill step. Furthermore, by designing the bonding structure obtained after the bonding step so that the substrate is connected to the non-bonding area of ​​the driver chip via the protective layer, the problem of the sidewalls of the light-emitting array structure being wrapped by the underfill glue layer, making it difficult to separate the substrate of the light-emitting array structure from the light-emitting chip, can be improved. Furthermore, the material selection of the protective layer is flexible and diverse, and can be made from a suitable material as needed, making the protective layer easier to completely remove than the underfill glue layer. This design effectively reduces the adverse effects of residual protective layer on the peripheral electrode surface on subsequent processes, successfully solving the problem of residual underfill glue on the peripheral electrode surface in the multi-chip bonding process, and significantly improving product reliability and yield.

[0150] In order to better implement the method for manufacturing the micro-light emitting device provided in the embodiment of the present application, the embodiment of the present application also provides a micro-light emitting device (such as Figure 16 As shown), the micro light-emitting device can be manufactured using any of the micro light-emitting device manufacturing methods provided in the embodiments of the present application.

[0151] Specifically, the above-mentioned micro-light-emitting device can be applied to any product with a display function, such as electronic paper, mobile phones, tablet computers, televisions, laptops, digital photo frames, wearable devices or navigation devices.

[0152] In addition, it should be noted that the micro-light-emitting device provided in the embodiment of the present application is manufactured using the manufacturing method of the micro-light-emitting device provided in the embodiment of the present application. Therefore, it can achieve the beneficial effects that can be achieved by any manufacturing method of the micro-light-emitting device provided in the embodiment of the present application. Please see the previous embodiment for details and will not be repeated here.

[0153] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for manufacturing a micro light-emitting device, characterized in that: include: Provided are a light-emitting array structure and a driver array structure, wherein the light-emitting array structure includes a substrate and a plurality of light-emitting chips disposed on one side of the substrate; the driver array structure includes a plurality of driver chips, each of the driver chips having a bonding area and a non-bonding area disposed around the bonding area, and including a peripheral electrode disposed on one side of the driver chip within the non-bonding area; forming a protective layer on a side of the driver chip provided with the peripheral electrode in the non-bonding area, wherein the protective layer at least covers the peripheral electrode; Bonding the light-emitting array structure to the driving array structure to obtain a bonding structure, wherein the light-emitting chip in the bonding structure is bonded to the driving chip in the bonding area, and the substrate in the bonding structure is connected to the driving chip in the non-bonding area through the protective layer; forming an underfill layer in the gap between the light emitting array structure and the driving array structure in the bonding structure; removing the substrate of the light-emitting array structure in the bonding structure to expose the protective layer; The protective layer exposed by removing the substrate is processed to expose the peripheral electrodes of the driving chip, and a micro light-emitting device is prepared based on the exposed peripheral electrodes.

2. The method for manufacturing a micro-light emitting device according to claim 1, wherein: A cutting path is provided between the plurality of driving chips, and the cutting path is located in the non-bonding area of ​​the plurality of driving chips; Furthermore, after forming an underfill layer in the gap between the light emitting array structure and the driving array structure in the bonding structure, the method further includes: The bonding structure is cut along the cutting path of the driving array structure in the bonding structure to obtain a plurality of micro light-emitting structures, each of which includes at least one light-emitting chip and at least one driving chip that are bonded to each other.

3. The method for manufacturing a micro-light emitting device according to claim 2, wherein: The micro light-emitting device prepared based on the exposed peripheral electrode includes: Disposing the micro-light emitting structure on one side of a circuit board; The peripheral electrodes of the driving chip in the micro-light-emitting structure are electrically connected to the pads of the circuit board to prepare a micro-light-emitting device.

4. The method for manufacturing a micro-light emitting device according to claim 1, wherein: The step of removing the protective layer exposed from the substrate to expose the peripheral electrodes of the driver chip includes: The protective layer exposed by removing the substrate is cleaned and removed to expose the peripheral electrodes of the driving chip.

5. The method for manufacturing a micro-light emitting device according to claim 1, wherein: The protective layer has a solidified state and a flowable state; the method further comprises: During the bonding process of the light-emitting array structure and the driving array structure, the protective layer is transformed from a solidified state to a flowable state. The protective layer in the flowable state is squeezed by the substrate in the light-emitting array structure and adheres to the substrate. Then, the protective layer is transformed from a flowable state to a solidified state. The protective layer in the solidified state connects the substrate in the light-emitting array structure and the driving chip in the driving array structure together.

6. The method for manufacturing a micro-light emitting device according to claim 1, wherein: The protective layer is formed on a side of the driver chip provided with the peripheral electrode in the non-bonding area, comprising: A protective layer is formed on a side of the driving array structure where the peripheral electrode is provided. The protective layer completely covers the non-bonding areas of the multiple driving chips and is arranged around the bonding area of ​​each driving chip in the driving array structure to form a plurality of accommodating areas. Each of the accommodating areas corresponds to one of the driving chips in the driving array structure, and the orthographic projection of each of the accommodating spaces on the driving array structure completely overlaps with the bonding area of ​​the corresponding driving chip.

7. The method for manufacturing a micro-light emitting device according to claim 1, wherein: The protective layer is located on a side of the driver array structure where the peripheral electrode is provided, and is arranged around the bonding area of ​​each driver chip in the driver array structure to form a plurality of accommodation areas, each of the accommodation areas corresponding to one driver chip in the driver array structure, a plurality of exhaust channels are opened on the sidewall of each accommodation space, and the interior of each accommodation space is connected to a designated position of an edge area of ​​the driver array structure through the plurality of exhaust channels; The step of forming an underfill layer in the gap between the light emitting array structure and the driving array structure in the bonding structure includes: An underfill is applied to the designated position of the edge region of the driving array structure in the bonding structure. The underfill is filled into the gap between the bonded driving chip and the light-emitting chip through the exhaust channel. The underfill is then cured to form an underfill layer that fills the gap between the bonded light-emitting array structure and the driving array structure.

8. The method for manufacturing a micro-light emitting device according to claim 1, wherein: The step of forming a protective layer on a side of the driver chip provided with the peripheral electrode in the non-bonding area comprises: forming a photoresist layer on a side of the driver chip where the peripheral electrode is provided; The photoresist layer is exposed and developed to at least expose the bonding area of ​​the driver chip, and the retained photoresist layer forms a protective layer.

9. The method for manufacturing a micro-light emitting device according to claim 1, wherein: The driving array structure is a driving wafer; The light emitting array structure is provided, comprising: Providing light-emitting wafers; The light-emitting wafer is cut to obtain a plurality of the light-emitting array structures.

10. A micro light-emitting device, characterized in that: The micro light-emitting device is manufactured by the manufacturing method according to any one of claims 1 to 9.

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