Light emitting element, light emitting assembly, and method for manufacturing light emitting assembly

Abstract

The application discloses a light emitting element, a light emitting component and a preparation method of the light emitting component. The light emitting element comprises a substrate, an epitaxial structure, an electrode and a coating. The epitaxial structure is arranged on the substrate; the electrode is arranged on the epitaxial structure; and the coating is arranged on a region of the epitaxial structure which is not covered by the electrode, and the viscosity of the coating is lower than that of the epitaxial structure. Alternatively, the first electrode of the light emitting diode light emitting element covers the entire first step surface. By covering the region of the epitaxial structure which is not covered by the electrode with the coating, and simultaneously due to the lower viscosity between the coating and the organic adhesive layer of the temporary substrate, the organic adhesive layer and the epitaxial structure can be prevented from excessive adhesion, and the problem of low pick-up yield in batch transfer can be prevented.

Description

Technical Field

[0001] This application relates to the field of display technology, specifically to a light-emitting element, a light-emitting component, and a method for preparing the light-emitting component. Background Technology

[0002] Micro-LEDs, with their advantages of high brightness, long lifespan, fast response speed, and high contrast, are widely used in display panels. However, existing flip-chip LED designs face challenges in controlling the depth of the LED embedded in the organic adhesive layer during batch transfer to temporary substrates or from temporary substrates to driving substrates. This difficulty in controlling the depth affects subsequent laser lift-off yield or pick-up yield during batch transfer. Summary of the Invention

[0003] In view of this, this application provides a light-emitting element, a light-emitting assembly, and a method for preparing the light-emitting assembly, to solve the problem in the prior art that the depth of the light-emitting element embedded in the organic adhesive layer is difficult to control, resulting in a low process yield.

[0004] To address the aforementioned technical problems, the first technical solution provided in this application is: to provide a light-emitting element, comprising a substrate, an epitaxial structure, an electrode, and a coating. The epitaxial structure is disposed on the substrate; the electrode is disposed on the epitaxial structure; the coating is disposed in the area of ​​the epitaxial structure not covered by the electrode, and the adhesion of the coating is lower than that of the epitaxial structure.

[0005] Wherein, the adhesion between the coating and the organic adhesive layer is lower than the adhesion between the epitaxial structure and the organic adhesive layer, and the organic adhesive layer is located on a temporary substrate for realizing the transfer of the light-emitting element; preferably, the coating is only disposed on the surface of the epitaxial structure away from the substrate.

[0006] The extensional structure is stepped and includes a first step surface and a second step surface, wherein the first step surface is higher than the second step surface;

[0007] The electrode includes a first electrode and a second electrode, wherein the first electrode is disposed on the first step surface and the second electrode is disposed on the second step surface; preferably, the coating covers the entire area of ​​the first step surface not covered by the first electrode and the coating covers the entire area of ​​the second step surface not covered by the second electrode.

[0008] Wherein, the coating is a polymer coating; or the coating is a metal coating and is disposed at a distance from the first electrode; preferably, the first electrode protrudes beyond the coating.

[0009] The light-emitting element further includes an inorganic insulating layer disposed in the area between the epitaxial structure and the coating that is not covered by the electrode, and the adhesion of the coating is lower than that of the inorganic insulating layer; preferably, the inorganic insulating layer is an oxide or nitride of silicon; preferably, the adhesion between the coating and the organic adhesive layer is lower than that between the inorganic insulating layer and the organic adhesive layer, and the organic adhesive layer is located on a temporary substrate for transferring the light-emitting element; preferably, the substrate is an epitaxial substrate, and the epitaxial structure is directly grown on the surface of the epitaxial substrate.

[0010] To solve the above-mentioned technical problems, the second technical solution provided in this application is: to provide a light-emitting element, including: a substrate and an epitaxial structure, wherein the epitaxial structure is disposed on the substrate; the epitaxial structure is stepped and includes a first step surface and a second step surface lower than the first step surface; a first electrode is disposed on the first step surface; a second electrode is disposed on the second step surface; wherein the first electrode covers the entire first step surface, and the adhesion of the first electrode is lower than the adhesion of the first step surface.

[0011] Wherein, the area of ​​the first electrode gradually decreases along the direction away from the first step surface; preferably, the adhesion between the first electrode and the organic adhesive layer is lower than the adhesion between the epitaxial structure and the organic adhesive layer, and the organic adhesive layer is located on a temporary substrate for realizing the transfer of the light-emitting element.

[0012] To solve the above-mentioned technical problems, the third technical solution provided in this application is: to provide a light-emitting component, including a driving substrate and an encapsulation substrate disposed opposite to each other; a light-emitting element disposed between the driving substrate and the encapsulation substrate; wherein the light-emitting element is any of the light-emitting elements described above.

[0013] To solve the above-mentioned technical problems, the fourth technical solution provided in this application is: a method for preparing a light-emitting component, comprising the following steps: providing a light-emitting element, wherein the light-emitting element is any of the light-emitting elements described above; pressing the electrodes of the light-emitting element into an organic adhesive layer of a temporary substrate; removing the substrate of the light-emitting element to expose the epitaxial structure of the light-emitting element; fixing the epitaxial structure of the light-emitting element onto an encapsulation substrate; removing the temporary substrate to expose the electrodes of the light-emitting element; and fixing the electrodes of the light-emitting element to a driving substrate.

[0014] The step of pressing the electrode of the light-emitting element into the organic adhesive layer of the temporary substrate includes: inserting the electrode portion into the organic adhesive layer and making the coating abut against the organic adhesive layer.

[0015] The beneficial effects of this application are as follows: Unlike existing technologies, the light-emitting element of this application includes a substrate, an epitaxial structure, an electrode, and a coating. The epitaxial structure is disposed on the substrate; the electrode is disposed on the epitaxial structure; the coating is disposed on the area of ​​the epitaxial structure not covered by the electrode, and the adhesion of the coating is lower than that of the epitaxial structure. Alternatively, the first electrode of the light-emitting element of this application covers the entire first step surface. By covering the area of ​​the epitaxial structure not covered by the electrode with a coating, and because the adhesion between the coating and the organic adhesive layer of the temporary substrate is lower, excessive adhesion between the organic adhesive layer and the epitaxial structure can be prevented, thus preventing the problem of low pick-up yield in batch transfer. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of the first embodiment of the light-emitting diode provided in this application;

[0018] Figure 2 yes Figure 1 A schematic diagram of the structure for transferring a light-emitting diode to a temporary substrate;

[0019] Figure 3 This is a schematic diagram of the structure of the second embodiment of the light-emitting diode provided in this application;

[0020] Figure 4 This is a front view structural schematic diagram of the third embodiment of the light-emitting diode provided in this application;

[0021] Figure 5 This is a top view of the third embodiment of the light-emitting diode provided in this application;

[0022] Figure 6 This is a front view structural schematic diagram of the fourth embodiment of the light-emitting diode provided in this application;

[0023] Figure 7 This is a top view of the fourth embodiment of the light-emitting diode provided in this application;

[0024] Figure 8 This is a schematic diagram of the structure of the fifth embodiment of the light-emitting diode provided in this application;

[0025] Figure 9 This is a schematic diagram of the sixth embodiment of the light-emitting diode provided in this application;

[0026] Figure 10 This is a structural schematic diagram of the seventh embodiment of the light-emitting diode provided in this application;

[0027] Figure 11 This is a schematic diagram of the structure of the eighth embodiment of the light-emitting diode provided in this application;

[0028] Figure 12 This is a front view structural schematic diagram of the ninth embodiment of the light-emitting diode provided in this application;

[0029] Figure 13 yes Figure 12 A schematic diagram of the structure for transferring a light-emitting diode to a temporary substrate;

[0030] Figure 14 This is a schematic diagram of the tenth embodiment of the light-emitting diode provided in this application;

[0031] Figure 15 This is a schematic diagram of the structure of an embodiment of the light-emitting component provided in this application;

[0032] Figure 16 This is a flowchart of the fabrication method of the light-emitting component provided in this application;

[0033] Figure 17 This is a process flow diagram of the method for fabricating the light-emitting component provided in this application;

[0034] Figure 18 This is a schematic diagram of the structure of an embodiment of the electronic device provided in this application. Detailed Implementation

[0035] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0036] The terms "first" and "second" in this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationships and movements between components in a specific orientation (as shown in the figures). If the specific orientation changes, the directional indications will also change accordingly. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0037] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0038] The existing batch transfer process first presses the Micro-LED into a temporary substrate through a bonding process, then removes the sapphire substrate of the light-emitting diode through a laser lift-off process, and finally picks up the light-emitting diode and bonds it to the thin film transistor (TFT) backplane through batch transfer.

[0039] However, due to factors such as equipment precision, flatness, sapphire flatness, and differences in the uniformity of various film layers in the current bonding process, it is difficult to control the depth of the LED embedded in the organic adhesive. This results in situations where the P-electrode is embedded too shallowly or completely. Shallow embedding leads to severe rotation, misalignment, and crystal flipping of the LED during the subsequent laser lift-off process. Complete embedding causes pick-up failure during batch transfer due to excessive adhesion (current LED structures typically have a SiO / SiN surface, which adheres strongly to the organic adhesive), thus affecting product yield and placing higher demands on the flatness, lifespan, and Q-time (tracking waiting time) of the transfer head in the transfer process.

[0040] To address the challenge of controlling the depth of LED embedding in the organic adhesive during the bonding process due to factors such as equipment precision, flatness, sapphire flatness, and differences in the uniformity of each film layer, resulting in either insufficient embedding or complete embedding, this application provides a light-emitting element, a light-emitting assembly, and a method for fabricating a light-emitting assembly using the light-emitting element. Furthermore, this application provides an electronic device using the light-emitting element. Specifically, the light-emitting element in this application is a light-emitting diode 100.

[0041] Please see Figures 1 to 2 , Figure 1 This is a schematic diagram of the structure of the first embodiment of the light-emitting diode provided in this application; Figure 2 yes Figure 1 A schematic diagram of the structure for transferring a light-emitting diode to a temporary substrate.

[0042] The light-emitting diode 100 includes a substrate 30, an epitaxial structure 20, a first electrode 10, a second electrode 11, and a coating 40.

[0043] Specifically, the light-emitting diode 100 can be a Micro-LED, selected as needed, and this application does not impose any restrictions. The substrate 30 supports the epitaxial structure 20; for example, the epitaxial structure 20 is disposed on the substrate 30. A coating 40 is disposed in the area of ​​the epitaxial structure 20 not covered by the electrodes (first electrode 10, second electrode 11), and the adhesion of the coating 40 is lower than that of the epitaxial structure 20. The first electrode 10 and the second electrode 11 are disposed on the epitaxial structure 20 and are electrically connected to the epitaxial structure 20 of the light-emitting diode 100, respectively. The first electrode 10 and the second electrode 11 are used to apply a voltage to the epitaxial structure 20 to make the epitaxial structure 20 emit light.

[0044] The coating 40 is disposed on the area of ​​the epitaxial structure 20 not covered by the electrode, and the adhesion of the coating 40 is lower than that of the epitaxial structure 20. By covering the epitaxial structure 20 with the coating 40, and because the adhesion of the coating 40 is lower than that of the epitaxial structure 20, the adhesion between the coating 40 and the organic adhesive layer on the temporary substrate is also lower. This prevents excessive adhesion between the organic adhesive layer and the epitaxial structure 20 during the transfer process, and prevents the problem of low pick-up yield in batch transfer.

[0045] In this embodiment, the substrate 30 is an epitaxial substrate, such as sapphire, and the epitaxial structure 20 is grown directly on the surface of the epitaxial substrate.

[0046] Using sapphire epitaxial substrate 30 has many advantages: sapphire substrate has mature production technology and good device quality; sapphire has good stability and can be used in high-temperature growth processes; sapphire has high mechanical strength and is easy to handle and clean.

[0047] like Figure 1As shown, the epitaxial structure 20 is disposed on the substrate 30 and includes a P-type semiconductor layer 21, an active layer 23 and an N-type semiconductor layer 22 stacked sequentially.

[0048] In one embodiment, the epitaxial structure 20 is stepped and includes a first stepped surface 210 and a second stepped surface 220 below the first stepped surface 210. The first stepped surface 210 is the surface of the P-type semiconductor layer 21 away from the N-type semiconductor layer 22, and the second stepped surface 220 is the surface of the N-type semiconductor layer 22 away from the substrate 30. A first electrode 10 is disposed on the first stepped surface 210, and a second electrode 11 is disposed on the second stepped surface 220.

[0049] Specifically, the first electrode 10 is a P-type electrode, and the second electrode 11 is an N-type electrode. The first step surface 210 is higher than the second step surface 220. The materials and structures of the first electrode 10 and the second electrode 11 are not limited and can be configured according to specific needs; for example, they can be metals or alloys. In this embodiment, the surface of the first electrode 10 away from the substrate 30 is flush with the surface of the second electrode 11 away from the substrate 30, which facilitates the simultaneous insertion of the first electrode 10 and the second electrode 11 into the organic adhesive layer.

[0050] The materials and structures of the P-type semiconductor layer 21 and the N-type semiconductor layer 22 are not limited, and can be configured according to specific needs. An active layer 23 is disposed between the P-type semiconductor layer 21 and the N-type semiconductor layer 22. The active layer 23 is used for stimulated light. The materials and thicknesses of the P-type semiconductor layer 21, the active layer 23, and the N-type semiconductor layer 22 are not limited, and can be configured according to specific needs.

[0051] In one embodiment, the epitaxial structure 20 further includes an inorganic insulating layer 50. The inorganic insulating layer 50 is disposed on the first step surface 210, and the coating 40 is disposed on the surface of the inorganic insulating layer 50 away from the first step surface 210. If there is no inorganic insulating layer 50, the coating 40 can be directly disposed on the first step surface 210. In this embodiment, only a light-emitting diode 100 having an inorganic insulating layer 50 is described.

[0052] Specifically, the inorganic insulating layer 50 includes a first inorganic insulating layer and a second inorganic insulating layer. The first inorganic insulating layer and the second inorganic insulating layer can be set separately or can be an integrated structure.

[0053] Specifically, the first inorganic insulating layer is disposed in the area of ​​the first stepped surface 210 not covered by the first electrode 10. That is, the first inorganic insulating layer and the first electrode 10 together cover the first stepped surface 210, with the first inorganic insulating layer surrounding the first electrode 10. It can be understood that the first inorganic insulating layer may only cover the upper surface of the first stepped surface 210, or it may extend to cover the side surface of the first stepped surface 210. In this embodiment, the first inorganic insulating layer is disposed only in the area of ​​the first stepped surface 210 not covered by the first electrode 10. Similarly, the second inorganic insulating layer is disposed in the area of ​​the second stepped surface 220 not covered by the second electrode 11. That is, the second inorganic insulating layer and the second electrode 11 together cover the second stepped surface 220, with the second inorganic insulating layer surrounding the second electrode 11. It can be understood that the second inorganic insulating layer may only cover the upper surface of the second stepped surface 220, or it may extend to cover the side surface of the second stepped surface 220. In this embodiment, the second inorganic insulating layer is disposed only in the area of ​​the second stepped surface 220 not covered by the second electrode 11.

[0054] When the first inorganic insulating layer and the second inorganic insulating layer are integrated, that is, when the first inorganic insulating layer and the second inorganic insulating layer form a single inorganic insulating layer 50, the inorganic insulating layer 50 covers the area of ​​the first stepped surface 210 not covered by the first electrode 10, and the area of ​​the second stepped surface 220 not covered by the second electrode 11. In other words, the integrated inorganic insulating layer 50 is stepped, extending from the surface of the first stepped surface 210, the side of the first stepped surface 210 near the second stepped surface 220, to the surface of the second stepped surface 220 not covered by the second electrode 11, forming a single integrated structure.

[0055] In this embodiment, the inorganic insulating layer 50 is a silicon oxide or nitride (SiO / SiN) film layer, which can prevent electrode leakage.

[0056] like Figure 1 The diagram shows the structure of the coating 40 of the light-emitting diode 100 in the first embodiment. The coating 40 is disposed in the area of ​​the first step surface 210 not covered by the first electrode 10, and the adhesion of the coating 40 is lower than that of the first step surface 210 (epitaxial structure 20). This is so that when the light-emitting diode 100 is transferred using a temporary substrate, the adhesion between the coating 40 and the organic adhesive layer 61 on the temporary substrate 60 is lower than that between the first step surface 210 (epitaxial structure 20) and the organic adhesive layer 61 on the temporary substrate 60. This prevents excessive adhesion between the organic adhesive layer and the first step surface 20 (epitaxial structure 20) during the transfer process, and prevents the problem of low pick-up yield in batch transfer.

[0057] Specifically, the coating 40 covers the area of ​​the first step surface 210 not covered by the first electrode 10. That is, the coating 40 and the first electrode 10 together cover the first step surface 210, with the coating 40 surrounding the first electrode 10. In this embodiment, the coating 40 completely covers the area of ​​the first step surface 210 not covered by the first electrode 10. It can be understood that when an inorganic insulating layer 50 is provided on the first step surface 210, the coating 40 is disposed on the surface of the inorganic insulating layer 50 away from the first step surface 210; when no inorganic insulating layer 50 is provided on the first step surface 210, the coating 40 is directly disposed on the first step surface 210.

[0058] The coating 40 can be configured to be lower than the first electrode 10, meaning the first electrode 10 protrudes beyond the coating 40, or it can be configured to be flush with the first electrode 10. In this embodiment, the first electrode 10 protrudes beyond the coating 40, meaning the height of the first electrode 10 is higher than the height of the coating 40. This has the advantages of making it easier for the first electrode 10 to be inserted into the organic adhesive layer 61; and also allowing the side of the first electrode 10 to contact the organic adhesive layer 61, resulting in a larger contact area and thus higher connection stability between the first electrode 10 and the organic adhesive layer 61.

[0059] It should be noted that, since the surface of the epitaxial structure 20 away from the substrate 30 in this application is a stepped surface, the coating 40 can be disposed on the entire stepped surface, including the first stepped surface 210, the second stepped surface 220, and the side surface where the first stepped surface 210 and the second stepped surface 220 are connected. However, the coating 40 is not covered on the side surface of the epitaxial structure 20, that is, there is no coating 40 between adjacent light-emitting diodes 100. Specifically, in this embodiment, the coating 40 is preferably disposed only on the surface of the epitaxial structure 20 away from the substrate 30 (the first stepped surface 210), that is, there is no coating 40 between adjacent light-emitting diodes 100. The reason is that when there is a coating 40 between adjacent light-emitting diodes 100, it is easy for the coating 40 to cover the substrate 30, so that the coating 40 and the substrate 30 are connected together. When the light-emitting diode 100 is transferred from the substrate 30 to the temporary substrate 60, during the peeling process of the substrate 30, the substrate 30 may detach the light-emitting diode 100 from the temporary substrate 60 through the coating 40.

[0060] The material of coating 40 satisfies the following condition: the adhesion between coating 40 and organic adhesive layer 61 is lower than that between the first step surface 210 or inorganic insulating layer 50 and organic adhesive layer 61. For example, the material of coating 40 is a non-adhesive or low-adhesion organic material, or a metal. In this embodiment, the material of coating 40 is a polymer. The polymer can be one or more of polytetrafluoroethylene, polystyrene, epoxy resin, acrylic resin, and silicone, or other materials.

[0061] When coating 40 is an insulating coating such as a polymer, coating 40 can be spaced apart from the first electrode 10 or the second electrode 11, or it can be in direct contact. Coating 40 can be an integral structure, or it can be separated into a first coating 41 and a second coating 42. When coating 40 is a conductive coating such as a metal, it needs to be spaced apart from the first electrode 10 and the second electrode 11 to avoid short circuit between the first electrode 10 and the second electrode 11.

[0062] In the process of fabricating the light-emitting component, the light-emitting diode 100 needs to be transferred from the substrate 30 to the temporary substrate 60. For example... Figure 2 As shown, the temporary substrate 60 includes an organic adhesive layer 61 and a glass substrate 62, with the organic adhesive layer 61 attached to the glass substrate 62. The adhesion of the coating 40 is lower than that of the first step surface 210 (epitaxial structure 20) or the inorganic insulating layer 50, resulting in lower adhesion between the coating 40 and the organic adhesive layer 61. This avoids the problem of high adhesion between the first step surface 210 (epitaxial structure 20) or the inorganic insulating layer 50 and the organic adhesive layer 61 during subsequent laser transfer processes, which would make peeling difficult. The lower adhesion of the coating 40 leads to lower viscosity between the coating 40 and the organic adhesive layer 61, resulting in higher pickup efficiency during the batch transfer and pickup of the light-emitting diodes 100 in subsequent laser transfer processes, improving product yield, and further improving the flatness of the transfer head in the transfer process, thus extending its service life.

[0063] Please see Figures 3 to 5 , Figure 3 This is a schematic diagram of the structure of the second embodiment of the light-emitting diode provided in this application; Figure 4 This is a front view structural schematic diagram of the third embodiment of the light-emitting diode provided in this application; Figure 5 This is a top view of the third embodiment of the light-emitting diode provided in this application.

[0064] like Figure 3 As shown, the structure of the light-emitting diode 100 provided in the second embodiment of this application is basically the same as that of the light-emitting diode 100 provided in the first embodiment. The difference is that the coating 40 can also cover the second step surface 220, completely covering the area of ​​the second step surface 220 not covered by the second electrode 11. Similarly, when an inorganic insulating layer 50 is provided on the second step surface 220, the coating 40 is provided on the inorganic insulating layer 50; when there is no inorganic insulating layer 50 on the second step surface 220, the coating 40 is directly provided on the second step surface 220.

[0065] It is understood that when both the first step surface 210 and the second step surface 220 are provided with coating 40, the coating 40 can be an integrated coating structure or two separate coatings. When the coating 40 is separated into two coatings, the coating 40 on the first step surface 210 is the first coating 41, and the coating 40 on the second step surface 220 is the second coating 42.

[0066] like Figure 3 As shown, when the first coating 41 and the second coating 42 are disposed separately, the first coating 41 is disposed in the area of ​​the first stepped surface 210 not covered by the first electrode 10. That is, the first coating 41 and the first electrode 10 together cover the first stepped surface 210. It can be understood that the first coating 41 may only cover the upper surface of the first stepped surface 210, or it may extend to cover the side surface of the first stepped surface 210. In this embodiment, the first coating 41 is disposed only in the area of ​​the first stepped surface 210 not covered by the first electrode 10. Similarly, the second coating 42 is disposed in the area of ​​the second stepped surface 220 not covered by the second electrode 11, that is, the second coating 42 and the second electrode 11 together cover the second stepped surface 220. It can be understood that the second coating 42 may only cover the upper surface of the second stepped surface 220, or it may extend to cover the side surface of the second stepped surface 220.

[0067] It should be noted that, since the surface of the epitaxial structure 20 away from the substrate 30 in this application is a stepped surface, the coating 40 can be disposed on the entire stepped surface, including the first stepped surface 210, the second stepped surface 220, and the side surface where the first stepped surface 210 and the second stepped surface 220 are connected. In this embodiment, the coating 40 is only disposed on the surface of the epitaxial structure 20 away from the substrate 30 (the first stepped surface 210, the second stepped surface 220, and the side surface where the first stepped surface 210 and the second stepped surface 220 are connected), that is, there is no coating 40 between adjacent light-emitting diodes 100. The reason is that when there is a coating 40 between adjacent light-emitting diodes 100, it is easy for the coating 40 to cover the substrate 30, so that the coating 40 and the substrate 30 are connected together. When the light-emitting diode 100 is transferred from the substrate 30 to the temporary substrate 60, during the peeling process of the substrate 30, the substrate 30 may detach the light-emitting diode 100 from the temporary substrate 60 through the coating 40.

[0068] like Figure 4 and Figure 5As shown, the light-emitting diode 100 provided in the third embodiment of this application has a basically the same structure as the light-emitting diode 100 provided in the second embodiment. The difference is that the first coating 41 and the second coating 42 are an integrated structure, that is, the first coating 41 and the second coating 42 form an integral coating 40. This coating 40 covers the area of ​​the first step surface 210 not covered by the first electrode 10, and the area of ​​the second step surface 220 not covered by the second electrode 11. In other words, the integrated coating 40 is stepped, extending from the surface of the first step surface 210 and the side of the first step surface 210 to the surface of the second step surface 220 not covered by the second electrode 11, forming an integrated coating structure.

[0069] Please see Figures 6 to 10 , Figure 6 This is a front view structural schematic diagram of the fourth embodiment of the light-emitting diode provided in this application; Figure 7 This is a top view of the fourth embodiment of the light-emitting diode provided in this application; Figure 8 This is a schematic diagram of the structure of the fifth embodiment of the light-emitting diode provided in this application; Figure 9 This is a schematic diagram of the sixth embodiment of the light-emitting diode provided in this application; Figure 10 This is a structural schematic diagram of the seventh embodiment of the light-emitting diode provided in this application.

[0070] like Figure 6 and Figure 7 As shown, the light-emitting diode 100 provided in the fourth embodiment of this application has a basically the same structure as the light-emitting diode 100 provided in the second embodiment. The difference is that both the first coating 41 and the second coating 42 are metal coatings. The first coating 41 and the second coating 42 are insulated from each other, and the first coating 41 and the first electrode 10, as well as the second coating 42 and the second electrode 11, are spaced apart to avoid short circuit between the first electrode 10 and the second electrode 11. It can be understood that when the coating 40 is a metal coating, if the first coating 41 is in contact with the first electrode 10, the second electrode 11 is in contact with the second coating 42, and the first coating 41 and the second coating 42 are connected as an integrated structure, the first electrode 10 and the second electrode 11 will be connected through the metal coating, resulting in a short circuit.

[0071] like Figure 8 As shown, the structure of the light-emitting diode 100 provided in the fifth embodiment of this application is basically the same as that of the light-emitting diode 100 provided in the fourth embodiment. The difference is that the first coating 41 is in contact with the first electrode 10, and the second coating 42 is in contact with the second electrode 11. Since the first coating 41 and the second coating 42 are provided with an insulating gap, short circuit between the first electrode 10 and the second electrode 11 can be avoided.

[0072] like Figure 9As shown, the LED 100 provided in the sixth embodiment of this application has a basically the same structure as the LED 100 provided in the fourth embodiment, except that the first coating 41 and the second coating 42 are connected as an integrated structure. Since the first coating 41 and the first electrode 10 are provided with an insulating gap, and the second coating 42 and the second electrode 11 are provided with an insulating gap, the first coating 41 and the second coating 42 can be connected together, so as not to cause a short circuit between the first electrode 10 and the second electrode 11.

[0073] like Figure 10 As shown, the structure of the light-emitting diode 100 provided in the seventh embodiment of this application is basically the same as that of the light-emitting diode 100 provided in the first embodiment, except that the first coating 41 is flush with the first electrode 10.

[0074] When the first coating 41 is flush with the first electrode 10, it can also be inserted into the organic adhesive layer 61 along with the first electrode 10, thus preventing the first stepped surface 210 or the inorganic insulating layer 50 from contacting the organic adhesive layer 61. However, since the contact area between the first electrode 10 and the organic adhesive layer 61 is smaller, the fixing effect is slightly worse than when the first electrode 10 protrudes beyond the first coating 41.

[0075] The first coating 41 being flush with the first electrode 10 can also be applied to other embodiments described above.

[0076] Please see Figures 11 to 14 , Figure 11 This is a schematic diagram of the structure of the eighth embodiment of the light-emitting diode provided in this application; Figure 12 This is a front view structural schematic diagram of the ninth embodiment of the light-emitting diode provided in this application; Figure 13 yes Figure 12 A schematic diagram of the structure for transferring a light-emitting diode to a temporary substrate; Figure 14 This is a schematic diagram of the tenth embodiment of the light-emitting diode provided in this application.

[0077] like Figure 11 As shown, the structure of the light-emitting diode 100 provided in the eighth embodiment of this application is basically the same as that of the light-emitting diode 100 provided in the first embodiment, except that the first electrode 10 covers the entire first step surface 210.

[0078] Specifically, the first electrode 10 covers the entire first step surface 210, and the adhesion of the first electrode 10 is lower than that of the first step surface 210 (epitaxial structure 20). This avoids contact between the first step surface 210 (epitaxial structure 20) and the organic adhesive layer 61, thereby preventing excessive viscosity between the first step surface 210 (epitaxial structure 20) and the organic adhesive layer 61, and avoiding the problem of difficulty in removing the organic adhesive layer 61 from the temporary substrate 60.

[0079] like Figure 12 As shown, the structure of the light-emitting diode 100 provided in the ninth embodiment of this application is basically the same as that of the light-emitting diode 100 provided in the eighth embodiment. The difference is that the area of ​​the first electrode 10 gradually decreases along the direction away from the first step surface 210.

[0080] Specifically, such as Figure 12 and Figure 13 As shown, the area of ​​the first electrode 10 can continuously decrease along the direction away from the first step surface 210. When the area of ​​the first electrode 10 continuously decreases along the direction away from the first step surface 210, a frustum structure is formed in which the first electrode 10 gradually decreases from near the first step surface 210 to away from the first step surface 210, that is, the longitudinal section of the first electrode 10 is trapezoidal, which makes it easier for the first electrode 10 to be inserted into the organic adhesive layer 61. Moreover, compared with the first electrode 10 of the light-emitting diode 100 provided in the eighth embodiment, the contact area between the first electrode 10 of the light-emitting diode 100 and the organic adhesive layer 61 is smaller in the ninth embodiment, which can avoid the problem of the first electrode 10 and the organic adhesive layer 61 having an excessively large contact area, making debonding difficult in the subsequent transfer step.

[0081] like Figure 14 As shown, the light-emitting diode 100 provided in the tenth embodiment of this application has a structure that is basically the same as that provided in the ninth embodiment, except that the area of ​​the first electrode 10 decreases gradually along the direction away from the first step surface 210. When the area of ​​the first electrode 10 decreases gradually along the direction away from the first step surface 210, a step-like structure is formed in which the first electrode 10 decreases gradually from near the first step surface 210 to away from the first step surface 210, and the longitudinal section of the first electrode 10 is stepped. It can be understood that the frustum structure in the ninth embodiment and the step-like structure in this embodiment can also be replaced by other shapes, as long as the first electrode 10 can cover the entire first step surface 210, and this application does not limit this.

[0082] Please see Figure 15 , Figure 15 This is a schematic diagram of the structure of an embodiment of the light-emitting component provided in this application.

[0083] The light-emitting component 200 is fabricated using the light-emitting diode 100 described in any of the first to tenth embodiments. It is understood that the light-emitting component can be a display panel or a light source, such as the backlight of a liquid crystal display (LCD). In this embodiment, the light-emitting component 200 is specifically a display panel, including a driving substrate 201 and an encapsulation substrate 202 disposed opposite to each other, with the light-emitting diode 100 disposed between the driving substrate 201 and the encapsulation substrate 202. The structure of the light-emitting diode 100 can be referred to the foregoing description and will not be repeated here.

[0084] The driving substrate 201 can be a rigid film material or a flexible film material. When the driving substrate 201 is a rigid film material, it can be glass, etc.; when the driving substrate 201 is a flexible film material, it can be PI adhesive, etc. The driving substrate 201 includes a driving circuit and a switch, and the driving circuit serves as the driving control unit of the light-emitting component 200.

[0085] The encapsulation substrate 202 covers the side of the plurality of light-emitting diodes 100 away from the driving substrate 201, and the encapsulation substrate 202 is made of a light-transmitting material.

[0086] It is understood that the light-emitting component 200 provided in this application can be applied to display devices such as desktop computers, laptops, personal digital assistants (PDAs), mobile phones, and televisions.

[0087] Please see Figures 16-17 , Figure 16 This is a flowchart of the fabrication method of the light-emitting component provided in this application; Figure 17 This is a process flow diagram of the fabrication method of the light-emitting component provided in this application.

[0088] This application provides a method for fabricating a light-emitting component, wherein the light-emitting component 200 is the same as described above, and will not be repeated here. Specifically, the method for fabricating the light-emitting component 200 includes the following steps:

[0089] S1: Provides light-emitting elements.

[0090] In step S1, the light-emitting element is any one of the light-emitting diodes 100 described in the above embodiments.

[0091] Specifically, in one embodiment, after the existing Micro-LED epitaxial process, a non-adhesive or low-adhesive coating 40 is added to the first step surface 210 (the adhesion of the coating 40 is lower than that of the first step surface 210, i.e., the epitaxial structure 20). This coating 40 can be a polymer coating or a metal coating. When the coating 40 is a polymer coating, the coating 40 can be in contact with the first electrode 10 or can be spaced apart. When the coating 40 is a metal coating, the coating 40 needs to be spaced apart from the first electrode 10 to prevent electrical connection between the metal coating and the first electrode 10. Since the coating 40 on the LED surface is a non-adhesive or low-adhesive material, when the first electrode 10 is completely pressed into the organic adhesive, the LED surface has no adhesion or low adhesion to the organic adhesive layer 61. This adhesion is moderate (compared to the adhesion of the inorganic layer on the surface of the existing LED structure), which can avoid situations such as pick-up failure during the batch transfer process.

[0092] In another embodiment, during the fabrication of the first electrode 10 on the first step surface 210 following existing Micro-LED epitaxial processes, the first electrode 10 covers the entire first step surface 210. Preferably, the area of ​​the second electrode 11 is smaller than that of the second step surface 220 to avoid short-circuiting between the second electrode 11 and the first electrode 10.

[0093] S2: Press the electrodes of the light-emitting element into the organic adhesive layer of the temporary substrate;

[0094] In step S2, the temporary substrate 60 includes an organic adhesive layer 61 and a glass substrate 62, with the organic adhesive layer 61 attached to the glass substrate 62.

[0095] When the light-emitting element is the LED 100 of the first to seventh embodiments described above, the adhesion between the coating 40 and the organic adhesive layer 61 is lower than that between the first step surface 210 or the inorganic insulating layer 50 and the organic adhesive layer 61. This avoids the problem of high adhesion between the first step surface 210 or the inorganic insulating layer 50 and the organic adhesive layer 61, which makes them difficult to peel off during subsequent laser transfer processes. The lower viscosity between the coating 40 and the organic adhesive layer 61 results in higher pick-up efficiency during the batch transfer and pickup process of the LED 100 in subsequent laser transfer processes, improving product yield and thus improving the flatness of the transfer head in the transfer process and extending its service life.

[0096] Due to the coating 40, the pressure can be appropriately increased during the bonding process to partially insert the first electrode 10 into the organic adhesive layer 61, ensuring that the coating 40 abuts against the organic adhesive layer 61. This avoids uneven depth at which the first electrode 10 of the LED sinks into the organic adhesive layer 61, while also reducing the requirements for the flatness of the sapphire epitaxial substrate and the uniformity of each film layer, achieving a stable and controllable bonding process. By fully pressing the first electrode 10 into the organic adhesive layer 61, the adhesion force is appropriately increased (compared to partial sinking), preventing rotation, misalignment, and flipping during the subsequent laser lift-off process.

[0097] Furthermore, when the light-emitting element is the light-emitting diode 100 of the eighth to tenth embodiments described above, since the adhesion between the first electrode 10 and the organic adhesive layer 61 is lower than that between the first step surface 210 or the inorganic insulating layer 50 and the organic adhesive layer 61, the problem of high adhesion between the first step surface 210 or the inorganic insulating layer 50 and the organic adhesive layer 61, which makes it difficult to peel off, can be avoided during the subsequent laser transfer process. This results in higher pick-up efficiency during the batch transfer and pick-up process of the light-emitting diode 100 in the subsequent laser transfer process, improving product yield, and further improving the flatness of the transfer head in the transfer process and extending its service life.

[0098] S3: Remove the substrate of the light-emitting element to expose the epitaxial structure of the light-emitting element;

[0099] In step S3, specifically, the substrate 30 of the light-emitting diode 100, that is, the sapphire epitaxial substrate of the light-emitting diode 100, is removed by laser lift-off or etching process.

[0100] S4: Fix the epitaxial structure of the light-emitting element onto the packaging substrate;

[0101] In step S3, the encapsulation substrate 202 is attached to the side of the epitaxial structure 20 of the light-emitting diode 100 that faces away from the temporary substrate 60. Specifically, the surface of the encapsulation substrate 202 has an organic adhesive layer to fix the epitaxial structure 20 of the light-emitting diode 100.

[0102] S5: Remove the temporary substrate to expose the electrodes of the light-emitting element;

[0103] In step S5, since the coating 40 or the first electrode 10 covers the entire first step surface 210, the light-emitting diode 100 is more easily transferred from the temporary substrate 60 to the packaging substrate 202, that is, the pickup efficiency is higher during the batch transfer and pickup process of the light-emitting diode 100.

[0104] S6: Fix the electrodes of the light-emitting element to the driving substrate.

[0105] In step S6, the driving substrate 201 is attached to one side of the electrode of the light-emitting diode 100 and electrically connected to the electrode. Specifically, the surface of the driving substrate 201 has an organic adhesive layer, and the driving substrate 201 has a driving circuit, which includes a thin-film transistor (TFT), so that the first electrode 10 and the second electrode 11 of the light-emitting diode 100 are respectively connected to the driving circuit.

[0106] Please see Figure 18 , Figure 18 This is a schematic diagram of the structure of an embodiment of the electronic device provided in this application.

[0107] An electronic device 300 includes the aforementioned light-emitting component 200 and processor 301. In this embodiment, the light-emitting component 200 is specifically a display panel, the specific structure of which can be referred to the foregoing description and will not be repeated here. The processor 301 is the central processing unit of the electronic device 300, used to control the display, communication, image acquisition, and image processing of the electronic device 300.

[0108] Specifically, the electronic device 300 can be a mobile phone, computer, digital broadcasting terminal, messaging device, game console, tablet device, medical device, fitness equipment, personal digital assistant, etc., and this application does not limit it.

[0109] Electronic device 300 may also include one or more of the following components: memory, power supply component, content to be deleted, processing component, multimedia component, audio component, input / output (I / O) interface, sensor component, and communication component.

[0110] The light-emitting diode disclosed in this application includes a substrate, an epitaxial structure, and a coating. The epitaxial structure is disposed on the substrate; the epitaxial structure is stepped and includes a first stepped surface and a second stepped surface lower than the first stepped surface; a first electrode is disposed on the first stepped surface; a second electrode is disposed on the second stepped surface; the coating is disposed on the area of ​​the epitaxial structure (first stepped surface, second stepped surface) not covered by the electrodes (first electrode, second electrode), and the adhesion of the coating is lower than the adhesion of the epitaxial structure (first stepped surface, second stepped surface), such that the adhesion between the coating and the organic adhesive layer is lower than the adhesion between the epitaxial structure (first stepped surface, second stepped surface) and the organic adhesive layer. Alternatively, the first electrode of the light-emitting diode of this application covers the entire first stepped surface. By covering the epitaxial structure (first stepped surface, second stepped surface) with a coating, and because the adhesion between the coating and the organic adhesive layer is lower, excessive adhesion between the organic adhesive and the epitaxial structure (first stepped surface, second stepped surface) can be prevented, thus preventing the problem of low pick-up yield during batch transfer.

[0111] The above are merely embodiments of this application and do not limit the scope of this patent application. Any equivalent structural or procedural changes made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A light-emitting element, characterized in that, include: Base; An epitaxial structure is disposed on the substrate; Electrodes are disposed on the epitaxial structure; A coating is disposed in the region of the epitaxial structure not covered by the electrode, and the adhesion of the coating is lower than that of the epitaxial structure; the adhesion between the coating and the organic adhesive layer is lower than that between the epitaxial structure and the organic adhesive layer, and the organic adhesive layer is used to realize the transfer of the light-emitting element.

2. The light-emitting element according to claim 1, characterized in that, The coating is applied only to the surface of the epitaxial structure that is away from the substrate.

3. The light-emitting element according to claim 1, characterized in that, The extensional structure is stepped and includes a first step surface and a second step surface, wherein the first step surface is higher than the second step surface; The electrode includes a first electrode and a second electrode, wherein the first electrode is disposed on the first step surface and the second electrode is disposed on the second step surface.

4. The light-emitting element according to claim 3, characterized in that, The coating covers the entire area of ​​the first stepped surface that is not covered by the first electrode, and the coating covers the entire area of ​​the second stepped surface that is not covered by the second electrode.

5. The light-emitting element according to claim 1, characterized in that, The coating is a polymer coating; or The coating is a metallic coating and is spaced apart from the electrode.

6. The light-emitting element according to claim 1, characterized in that, The light-emitting element also includes: An inorganic insulating layer is disposed in the region between the epitaxial structure and the coating that is not covered by the electrode, and the adhesion of the coating is lower than that of the inorganic insulating layer.

7. The light-emitting element according to claim 6, characterized in that, The adhesion between the coating and the organic adhesive layer is lower than that between the inorganic insulating layer and the organic adhesive layer, and the organic adhesive layer is located on a temporary substrate for transferring the light-emitting element.

8. A light-emitting element, characterized in that, include: Base; An epitaxial structure is disposed on the substrate; The extensional structure is stepped and includes a first stepped surface and a second stepped surface that is lower than the first stepped surface; The first electrode is disposed on the first step surface; The second electrode is disposed on the second step surface; Wherein, the first electrode covers the entire first step surface, and the adhesion of the first electrode is lower than that of the first step surface; the adhesion between the first electrode and the organic adhesive layer is lower than that between the epitaxial structure and the organic adhesive layer, and the organic adhesive layer is used to realize the transfer of the light-emitting element.

9. The light-emitting element according to claim 8, characterized in that, The area of ​​the first electrode gradually decreases along the direction away from the first step surface.

10. A light-emitting component, characterized in that, include: The driving substrate and the packaging substrate are positioned opposite each other; The light-emitting element is disposed between the driving substrate and the packaging substrate; Wherein, the light-emitting element is the light-emitting element according to any one of claims 1-9.

11. A method for preparing a light-emitting component, characterized in that, Includes the following steps: A light-emitting element is provided, wherein the light-emitting element is the light-emitting element according to any one of claims 1-9; The electrodes of the light-emitting element are pressed into the organic adhesive layer of the temporary substrate; Remove the substrate of the light-emitting element to expose the epitaxial structure of the light-emitting element; The epitaxial structure of the light-emitting element is fixed on the packaging substrate; Remove the temporary substrate to expose the electrodes of the light-emitting element; The electrodes of the light-emitting element are fixedly connected to the driving substrate.

12. The method for preparing a light-emitting component according to claim 11, characterized in that, The step of pressing the electrodes of the light-emitting element into the organic adhesive layer of the temporary substrate includes: The electrode portion is inserted into the organic adhesive layer, and the coating is brought into contact with the organic adhesive layer.

Images