LED chip assembly, preparation method thereof and display panel preparation method

Abstract

The application provides an LED chip assembly, a preparation method thereof, and a display panel preparation method. In the process of transferring the LED chip to the driving backboard, as long as the LED chip assembly is aligned with the driving backboard and the front and back surfaces of the LED chip face the driving backboard, the LED chip can be directly dropped to the chip receiving area of the driving backboard under the pressure of the operating body, the transfer process is simple and convenient, and in the case that multiple operating bodies work at the same time, multiple LED chips can be transferred to the driving backboard at the same time, and the transfer efficiency of the LED chip is improved. In addition, the dropping process of the LED chip is actually the process of the LED chip passing through the through hole, and the movement of the LED chip in the horizontal direction when passing through the through hole is limited by the side wall of the through hole. Therefore, the side wall of the through hole can be used to limit the offset of the LED chip in the horizontal direction during the dropping process, the offset and overturning of the LED chip are reduced, the accuracy of the transfer position of the LED chip is improved, and the transfer yield of the LED chip is improved.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to an LED chip component and its preparation method, and a display panel preparation method. Background Technology

[0002] After Micro-LEDs (micro-light-emitting diodes) are fabricated on a wafer, they typically require two or more transfers to be bonded to a driver backplane to achieve the display panel fabrication. Due to the small size of Micro-LEDs, mass transfer is necessary, meaning a large number of chips are transferred to the driver backplane at once. In some production scenarios, transfer rates for Micro-LEDs need to reach 3 × 10⁻⁶ per hour. 6 Currently, many manufacturers choose to use micro-stamp transfer technology to transfer Micro-LEDs to the driver backplane using van der Waals forces. However, the transfer yield and efficiency of micro-stamp transfer technology are not ideal. Therefore, how to quickly transfer Micro-LEDs to the driver backplane is an urgent problem to be solved. Summary of the Invention

[0003] In view of the shortcomings of the above-mentioned related technologies, the purpose of this application is to provide an LED chip component and its preparation method, as well as a display panel preparation method, in order to solve the problem of low LED chip transfer efficiency and yield.

[0004] This application provides an LED chip assembly, including:

[0005] A patterned substrate with multiple through-holes;

[0006] A patterned support layer disposed on one side of a patterned substrate and bonded to the patterned substrate; and

[0007] Multiple LED chips, at least partially inserted into the penetration opening;

[0008] The LED chip is partially embedded in the patterned support layer, with its front side facing away from the patterned support layer. The patterned support layer and the LED chip are cut out at a position opposite to the back side, allowing an operating body to extend through the cutout and touch the LED chip to apply pressure to the LED chip, causing it to detach from the patterned support layer and exit through the through-hole. The front side and the back side are respectively the side of the LED chip facing the drive back plate and the side facing away from the drive back plate when the LED chip is fixed on the drive back plate.

[0009] In the aforementioned LED chip assembly, the LED chip portion is embedded in a patterned support layer, and the patterned support layer is bonded to a patterned substrate. This allows the LED chip to be suspended and supported in the through-hole of the patterned substrate before being transferred to the driving backplane. Simultaneously, the exposed portion of the patterned support layer relative to the LED chip's back side ensures that an external operating body can reach and touch the LED chip through the cutout during the transfer process. This applies pressure to the LED chip, causing it to detach from the patterned support layer and fall through the through-hole in the patterned substrate. Therefore, during the transfer of the LED chip from the LED chip assembly to the driving backplane, simply aligning the LED chip assembly with the driving backplane and ensuring the front and back sides of the LED chip face the driving backplane guarantees that the LED chip will fall directly into the chip receiving area of ​​the driving backplane under pressure from the operating body. The transfer process is simple and convenient, and with multiple operating bodies working simultaneously, multiple LED chips can be transferred to the driving backplane at the same time, improving the transfer efficiency. In addition, the process of the LED chip falling is actually the process of the LED chip passing through the through hole. When the LED chip passes through the through hole, its horizontal movement is restricted by the side wall of the through hole. This can be achieved by using the side wall of the through hole to limit the horizontal displacement of the LED chip during the falling process, reducing the displacement and flipping of the LED chip, improving the accuracy of the LED chip transfer position, and improving the transfer yield of the LED chip.

[0010] Optionally, the patterned support layer and the LED chip are provided with perforated operation holes at positions opposite to the back side.

[0011] In the aforementioned LED chip assembly, the patterned support layer has a hollowed-out operating hole at a position opposite to the back of the LED chip. The operating hole has a relatively small cross-sectional area, and usually only the operating body can be inserted into it. This can reduce the probability of the LED chip falling off due to external impact or other reasons during transportation, thereby improving the reliability of the LED chip assembly.

[0012] Optionally, the distance between the side of the patterned substrate away from the patterned support layer and the front and back sides of the LED chip is greater than the height of the LED chip.

[0013] In the aforementioned LED chip assembly, because the distance between the side of the patterned substrate away from the patterned support layer and the front and back sides of the LED chip is greater than the height of the LED chip, this ensures that the height of the already bonded LED chips on the driver backplate will not affect the alignment of the patterned substrate and the driver backplate in the LED chip assembly, which is beneficial to improving the transfer yield of LED chips in the LED chip assembly.

[0014] Based on the same inventive concept, this application also provides a method for fabricating an LED chip assembly, comprising:

[0015] A carrier substrate with multiple LED chips and a temporary transfer substrate with multiple grooves are provided. The temporary transfer substrate includes an overlapping temporary substrate and a patterned substrate with multiple through holes. The grooves are formed by the through holes.

[0016] Bonding blocks are set on the front and back sides of the LED chip. The front and back sides are the side of the LED chip facing the driving back plate when it is fixed on the driving back plate, and the front and back sides of the LED chip face away from the carrier substrate.

[0017] After aligning the carrier substrate with the patterned substrate, at least part of the LED chip is placed in the through hole until the bonding block is bonded to the bottom of the groove.

[0018] After removing the carrier substrate, a patterned support layer is provided on the side of the patterned substrate away from the temporary substrate. The patterned support layer is attached to the patterned substrate and the LED chip, and the patterned support layer and the LED chip are cut out at positions opposite to the back side.

[0019] The temporary substrate and bonding block are removed to obtain the LED chip assembly.

[0020] In the above-mentioned LED chip assembly fabrication method, on the one hand, a temporary transfer substrate with multiple grooves is formed by a temporary substrate and a patterned substrate. On the other hand, a bonding block is set on the front and back sides of the LED chip. Then, after aligning the carrier substrate and the patterned substrate, the LED chip is placed at least partially in the through hole until the bonding block is bonded to the bottom of the groove. Therefore, when the carrier substrate is peeled off, the bonding block can also support the LED chip in the through hole. In this case, a patterned support layer is set on the side of the patterned substrate away from the temporary substrate. This patterned support layer is not only attached to the patterned substrate but also to the LED chip. Therefore, after the temporary transfer substrate and the bonding block are removed, the patterned support layer can provide a force to the LED chip to balance the weight of the LED chip, so that the LED chip can continue to be suspended in the through hole. Meanwhile, the exposed position of the patterned support layer relative to the back side of the LED chip ensures that during the transfer of the LED chip to the driver backplane, the external operating body can extend through the cutout and touch the LED chip, applying pressure to it. This pressure causes the LED chip to detach from the patterned support layer and fall through the through-hole on the patterned substrate. Therefore, during the transfer of the LED chip from the LED chip assembly to the driver backplane, simply aligning the LED chip assembly with the driver backplane and ensuring the front and back sides of the LED chip face the driver backplane guarantees that the LED chip will fall directly into the chip receiving area of ​​the driver backplane under the pressure of the operating body. The transfer process is simple and convenient, and with multiple operating bodies working simultaneously, multiple LED chips can be transferred to the driver backplane at the same time, improving the transfer efficiency of the LED chips. In addition, the process of the LED chip falling is actually the process of the LED chip passing through the through hole. When the LED chip passes through the through hole, its horizontal movement is restricted by the side wall of the through hole. This can be achieved by using the side wall of the through hole to limit the horizontal displacement of the LED chip during the falling process, reducing the displacement and flipping of the LED chip, improving the accuracy of the LED chip transfer position, and improving the transfer yield of the LED chip.

[0021] Based on the same inventive concept, this application also provides a method for manufacturing a display panel, comprising:

[0022] Provides a driver backplane and the aforementioned LED chip assembly;

[0023] Align the driver backplane with the LED chip assembly, with the front and back faces of the LED chip facing and opposite the chip receiving area of ​​the driver backplane;

[0024] The control unit extends from the cutout of the patterned support layer, presses against the back side of the LED chip, and applies pressure to the LED chip until the LED chip falls into the chip receiving area;

[0025] The LED chips in the chip receiving area are bonded to the driver backplane to produce the display panel.

[0026] In the aforementioned display panel manufacturing method, when transferring LED chips from the LED chip assembly to the driving backplate, simply aligning the LED chip assembly with the driving backplate and ensuring the front and back faces of the LED chips guarantees that the LED chips will fall directly into the chip receiving area of ​​the driving backplate under the pressure of the operating body. This transfer process is simple and convenient. Furthermore, with multiple operating bodies working simultaneously, multiple LED chips can be transferred to the driving backplate at the same time, improving the transfer efficiency. Additionally, the process of the LED chip falling is essentially the process of the LED chip passing through the through-hole. The horizontal movement of the LED chip through the through-hole is restricted by the sidewall of the through-hole. This allows for the use of the through-hole sidewall to limit the horizontal offset of the LED chip during its fall, reducing offset and flipping, improving the accuracy of the LED chip transfer position, and increasing the transfer yield. The improved LED chip transfer yield and efficiency reduce the production cost of the display panel. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a structure of an LED chip assembly provided in an optional embodiment of this application;

[0028] Figure 2 This is a top view schematic diagram of a patterned substrate provided in an optional embodiment of this application;

[0029] Figure 3a This is a schematic diagram illustrating, in an optional embodiment of this application, the removal of an LED chip from an LED chip assembly using an operating body;

[0030] Figure 3b This is a schematic diagram showing the alignment of an LED chip assembly with a driver backplane in an optional embodiment of this application;

[0031] Figure 3c This is a schematic diagram showing the alignment of another LED chip assembly with a driver backplane in an optional embodiment of this application;

[0032] Figure 4a This is a schematic diagram showing the positional relationship between the patterned support layer and the LED chip in an optional embodiment of this application;

[0033] Figure 4b This is a schematic diagram illustrating another positional relationship between the patterned support layer and the LED chip in an optional embodiment of this application;

[0034] Figure 5This is a schematic flowchart of a display panel manufacturing method provided in an optional embodiment of this application;

[0035] Figure 6 This is a schematic diagram illustrating a process state change during the fabrication of a display panel provided in an optional embodiment of this application;

[0036] Figure 7 This is a schematic flowchart of an LED chip assembly fabrication method provided in another optional embodiment of this application;

[0037] Figure 8 This is a schematic diagram illustrating a process state change in the fabrication of an LED chip assembly provided in another optional embodiment of this application;

[0038] Figure 9 This is a schematic diagram illustrating a process state change of a temporary transfer substrate provided in another optional embodiment of this application;

[0039] Figure 10a This is a top view schematic diagram of an LED chip assembly provided in another optional embodiment of this application;

[0040] Figure 10b This is a top view schematic diagram of another LED chip assembly provided in another optional embodiment of this application;

[0041] Figure 11 This is a schematic flowchart of a display panel manufacturing method provided in another optional embodiment of this application;

[0042] Figure 12 A schematic diagram illustrating a process state change in the fabrication of a display panel provided in yet another optional embodiment of this application;

[0043] Figure 13 This is a schematic diagram of a process state change in the fabrication of an LED chip provided in another optional embodiment of this application.

[0044] Explanation of reference numerals in the attached figures:

[0045] 10-LED chip assembly; 11-Patterned substrate; 110-Through-hole; 12-Patterned support layer; 120-Operating hole; 13-LED chip; 30-LED chip assembly; 31-Driver backplane; 32-Bonded LED chip; 61-LED chip assembly; 62-Driver backplane; 620-Chip receiving area; 81-Carrier substrate; 82-Temporary transfer substrate; 820-Groove; 821-Temporary substrate; 822-Bonding layer; 823-Bonding block; 1 201-Growth substrate; 1202-Epipolar layer; 1203-ITO pattern; 1204-DBR pattern; 1205-Chip electrode; 1206-LED chip; 1207-Temporary substrate; 1208-Patterned substrate; 1209-Through-hole; 1210-BCB bonding adhesive layer; 1211-BCB bonding block; 1212-SiO2 layer; 1213-Operating hole; 1214-LED chip assembly; 1215-Drive backplane; 1216-Ejector pin. Detailed Implementation

[0046] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0048] Micro-LED technology refers to a high-density integrated array of tiny LEDs on a driver backplane, reducing the pixel size of displays from millimeters to micrometers. Compared to traditional display technologies, Micro-LED has significant advantages, including high brightness, high efficiency, high reliability, and fast response time. Furthermore, the electroluminescence and small size of Micro-LEDs are making their applications increasingly widespread.

[0049] However, the lack of a good solution for transferring Micro-LED chips to the driver backplane has seriously affected the production efficiency of display panels and restricted the development of Micro-LED technology.

[0050] Therefore, this application aims to provide a solution that can solve the above-mentioned technical problems, the details of which will be described in subsequent embodiments.

[0051] An optional embodiment of this application: This embodiment first provides an LED chip assembly, please refer to... Figure 1 The diagram shows a structural schematic of the LED chip assembly 10: the LED chip assembly 10 includes a patterned substrate 11, a patterned support layer 12, and multiple LED chips 13.

[0052] In this embodiment, LED chip 13 can be the aforementioned Micro-LED chip, or a Min-LED (mini light-emitting diode) chip, or a larger LED chip. In some examples of this embodiment, LED chip 13 can also be an OLED (Organic Light-Emitting Diode) chip. Furthermore, this embodiment does not limit the structural type or color type of LED chip 13; it can be a flip-chip or a standard-chip, a vertical or horizontal structure, and can be a three-primary-color (red, green, blue) chip or an LED chip of colors other than the three primary colors.

[0053] Because different types of LED chips have different light-emitting surfaces and electrode configurations, it is difficult to represent the orientation of different types of LED chips with the same structural feature. Therefore, for the convenience of describing the setting of LED chip 13 in LED chip assembly 10 later, this embodiment defines the "facing side" and "away side" of LED chip 13 according to its orientation when it is fixed to the driver backplane. The facing side refers to the side of LED chip 13 that faces (or towards) the driver backplane after it is bonded to the driver backplane, while the away side refers to the side of LED chip 13 that faces away from the driver backplane after it is bonded to the driver backplane, i.e., the side of LED chip 13 opposite to its facing side. Taking a flip-chip LED chip as an example, its facing side is the side where the chip electrodes are located, while the away side is its main light-emitting surface. However, in a conventionally mounted LED chip, the side where the chip electrodes are located is the away side, while the facing side is the side opposite to the side where the chip electrodes are located.

[0054] The patterned substrate 11 has multiple through-holes 110, which are undoubtedly openings that penetrate both the upper and lower surfaces of the patterned substrate 11. Please refer to... Figure 2A top view of the patterned substrate 11 is shown: multiple through-holes 110 are arranged in an array on the patterned substrate 11. However, those skilled in the art will understand that in other examples, the arrangement of the through-holes 110 can also adopt other schemes. However, since the LED chip 13 is supported in the through-holes 110, the arrangement of the through-holes 110 on the patterned substrate 11 will affect the arrangement of the LED chip 13. Typically, the LED chip 13 in the LED chip assembly 10 is directly transferred to the driving backplane. Therefore, in some examples, the arrangement of the through-holes 110 on the patterned substrate 11 will refer to the arrangement of each chip receiving area on the driving backplane. Furthermore, since the LED chip 13 in the LED chip assembly 10 is directly transferred from the carrier substrate (e.g., the growth substrate), the arrangement of the through-holes 110 on the patterned substrate 11 will also refer to the arrangement of the LED chip 13 on the carrier substrate. Additionally, although... Figure 2 The cross-section of each through-hole 110 is rectangular, but the shape of the through-hole 110 is not limited in this embodiment. For example, the cross-section of the through-hole 110 can also be circular, elliptical, parallelogram, etc., as long as the through-hole 110 can allow the LED chip 13 to pass from one side to the other in an orientation that is parallel to the plane of the patterned substrate 11.

[0055] It is understood that the patterned substrate 11 has a certain thickness. Therefore, the through-hole 110 is essentially a channel through which the LED chip 13 can pass. The cross-sectional size of the through-hole 110 determines the maximum range of movement of the LED chip 13 in the direction parallel to the patterned substrate 11 when it passes through the channel. In this embodiment, in order to prevent the LED chip 13 from undergoing large positional shifts or flipping during its passage through the through-hole 110, the cross-sectional size of the through-hole 110 is made relatively small. For example, in some examples of this embodiment, the cross-sectional size of the through-hole 110 is only slightly larger than the cross-sectional size of the LED chip 13.

[0056] The patterned support layer 12 is bonded to the patterned substrate 13 on one hand, and also attached to the LED chip 13 on the other, so that a portion of the LED chip 13 is embedded in the patterned support layer 12. This allows the other side of the LED chip 13 to be suspended and supported in the through-hole 110 without any other support. Please continue reading... Figure 1 In this embodiment, the patterned support layer 12 is disposed on one side of the patterned substrate 13, which is the side of the LED chip 13 away from the back side. In other words, the patterned support layer 12 is disposed on the side of the LED chip 13 away from the back side, and the front side of the LED chip 13 faces away from the patterned support layer 12.

[0057] In this embodiment, when the LED chip 13 is suspended in the through-hole 110, at least a portion of its back surface is exposed to the patterned support layer 12. Therefore, the patterned support layer 12 is hollowed out at the position opposite to the back surface of the LED chip 13. When it is necessary to peel the LED chip 13 from the LED chip assembly 10, an operating body (such as a ejector pin) can be inserted from the hollowed-out position of the patterned support layer 12 and touch the back surface of the LED chip 13. When the operating body applies pressure to the back surface of the LED chip 13, the LED chip 13 will move away from the patterned support layer 12, thereby detaching from the patterned support layer 12 and leaving the LED chip assembly 10 through the other side of the through-hole 110 (i.e., the side opposite to the side where the patterned support layer 12 is located), as shown in Figure 3.

[0058] In some examples of this embodiment, the patterned support layer 12 is connected to the cutout areas of different LED chips 13 at positions opposite to the back surface, that is, the cutout areas of different LED chips 13 on the patterned support layer 12 are connected. In other examples, the cutout areas of each LED chip 13 on the patterned support layer 12 are independent of each other. For example, in some examples, an operation hole 120 is provided on the patterned support layer 12 at a position opposite to the back surface of each LED chip 13, for example... Figure 1 In this design, the operating hole 120 allows operating objects such as ejector pins to extend into it. Typically, the cross-sectional dimension of the operating hole 120 is smaller than the back surface of the LED chip. This means that the smaller the operating hole 120, the more difficult it is for ordinary objects to reach the back surface of the LED chip 13 through it. This prevents the LED chip 13 from detaching from the LED chip assembly 10 due to pressure from external objects during handling and transportation. Simultaneously, the size of the operating hole 120 does not affect the penetration of operating objects specifically designed for peeling off the LED chip 13. Therefore, when it is necessary to transfer the LED chip 13 from the LED chip assembly 10 to the driver backplane, the LED chip 13 can be easily peeled off using specialized operating objects such as ejector pins, which helps improve the quality and reliability of the LED chip assembly. Of course, in some other examples of this embodiment, the cross-sectional dimension of the operating hole 120 may also be greater than or equal to the dimension of the LED chip 13 from the back surface. For example, in one example of this embodiment, the patterned support layer 12 is attached to all four sides of the LED chip 13, but not to its back surface, so the cross-sectional area of ​​the operating hole 120 is equal to the area from the back surface; in another example, the patterned support layer 12 is attached to only one or two sides of the LED chip 13, and there is a certain gap between the other two sides and the patterned support layer 12, so in this case the area of ​​the operating hole 120 will be greater than the area of ​​the LED chip 13 from the back surface.

[0059] The shape of the cross-section of the operating hole 120 includes, but is not limited to, circles, ovals, rhombuses, triangles, rectangles, etc. In addition, it can also be trapezoidal, pentagonal, and other regular or irregular shapes.

[0060] Understandably, when transferring LED chips to a driver backplane to fabricate a display panel, not all the required LED chips on the driver backplane are transferred at once. For example, LED chips of different colors are typically transferred to the driver backplane in batches; even LED chips of the same color are likely to be transferred in multiple batches. This results in situations where some LED chips are transferred to the driver backplane when there are already bonded LED chips on the driver backplane. Furthermore, during LED chip repair, when transferring the repaired LED chips to the repair location on the driver backplane, a large number of LED chips are already present in other locations on the driver backplane. In this situation, if LED chips 13 are directly peeled from the LED chip assembly to the driver backplane, after the LED chip assembly is aligned with the driver backplane, some of the LED chips 13 will correspond to the already bonded LED chips 32 on the driver substrate. If the distance between the front and back faces of the LED chip 13 in the LED chip assembly 30 and the side of the patterned substrate 11 facing the driving backplate 31 is too small, for example, less than the height of the bonded LED chip 32 on the driving backplate 31, the distance between the LED chip assembly 30 and the driving backplate 31 will be interfered with by the height of the bonded LED chip 32, resulting in... Figure 3b This situation leads to a situation where the LED chip 13, after being peeled from the LED chip assembly 30 and exiting the through-hole 110 in the patterned substrate 11, cannot directly reach the driving backplate 31 but needs to continue falling a certain distance. During this distance, because there is no limiting force from the through-hole 110, the LED chip 13 may shift or flip, which will affect the transfer yield of the LED chip 13 in the LED chip assembly 30. Therefore, in order to avoid the height of the bonded LED chip 32 on the driving backplate 31 affecting the distance between the LED chip assembly and the driving backplate, and to improve the transfer yield of the LED chip in the LED chip assembly, in some LED chip assemblies provided in this embodiment, such as the LED chip assembly 10, the distance between the facing side of the LED chip 13 and the side of the patterned substrate 11 facing the driving backplate (i.e., the side of the patterned substrate 11 away from the patterned support layer 12) is greater than the height of the LED chip 13. In this way, even if there are bonded LED chips on the driving backplate, the remaining space in the through-hole 110 of the patterned substrate 11 is sufficient to accommodate the bonded LED chip 32. Figure 3c As shown.

[0061] In some examples of this embodiment, the patterned support layer 12 may be attached only to the back side of the LED chip 13. Please refer to [link to relevant documentation]. Figure 4aAs shown; in other examples, the patterned support layer 12 may be attached only to one or more sides of the LED chip 13, but not to the back side of the LED chip 13, such as... Figure 4b As shown; there is also a patterned support layer 12 that can be simultaneously attached to both the back and side surfaces of the LED chip 13, please refer to [link / reference]. Figure 1 In some examples of this embodiment, the patterned support layer 12 may be located only on one side of the patterned substrate 11 without being embedded in the through-hole 110. In other examples, the patterned support layer 12 may be attached to the surface of the patterned substrate 11 while being partially embedded in the through-hole 110. In some examples of this embodiment, the LED chip 13 protrudes from the back surface of the patterned substrate 11, such as... Figure 4b and Figure 1 As shown, in other examples, the back surface of the LED chip 13 can be flush with the surface of the patterned substrate 11. Please refer to [link to previous examples]. Figure 4a In some examples, the back side of the LED chip 13 may also be located within the through-hole 110.

[0062] Typically, the patterned support layer 12 has little or no deformation capability. This prevents the patterned support layer 12 from continuing to follow the LED chip 13 due to deformation when the LED chip 13 tends to move away from the patterned support layer 12 under pressure from the operating body, thus avoiding the problem of the LED chip 13 being difficult to separate from the patterned support layer 12. By using a material with little or no deformation capability to form the patterned support layer 12, it is ensured that when the LED chip 13 tends to move away from the patterned support layer 12 under pressure from the operating body, the patterned support layer 12 cannot deform and can only separate from the LED chip 13, allowing the LED chip 13 to detach from the patterned support layer 12 relatively cleanly. Therefore, in this embodiment, the patterned support layer 12 can be a brittle material with a breaking stress lower than or far below the yield strength of the material. In some examples of this embodiment, the material of the patterned support layer 12 includes, but is not limited to, SiO2 (silicon oxide), graphite, and metals (including metals with high carbon content, such as cast iron).

[0063] To help those skilled in the art better understand the process of stripping LED chips from LED chip assemblies, the following section combines... Figure 5 as well as Figure 6 The process of manufacturing a display panel using this LED chip assembly is described below:

[0064] S502: Provides a driver backplane and the aforementioned LED chip assembly.

[0065] The LED chip assembly 61 provided in this embodiment is Figure 1 The LED chip assembly 10 shown in the figure, such as Figure 6 As shown in (a) above, however, those skilled in the art will understand that LED chip component 10 may also be other LED chip components described in the foregoing examples.

[0066] The chip carrier surface of the driving backplane 62 includes multiple backplane electrodes. Two of these backplane electrodes form a group to constitute a backplane electrode group. The area where a backplane electrode group is located is a chip receiving area 620, which needs to receive LED chips 13 from the LED chip assembly 61.

[0067] S504: Align the driver backplane with the LED chip assembly, with the front and back faces of the LED chip facing and opposite the chip receiving area of ​​the driver backplane.

[0068] After obtaining the driving backplate 62 and the LED chip assembly 61, the driving backplate 62 and the LED chip assembly 61 can be aligned. Since the LED chip 13 needs to fall onto the driving backplate 62 under gravity after being pushed off the patterned support layer 12 by the manipulated object, when aligning the driving backplate 62 and the LED chip assembly 61, it is necessary to ensure that the LED chip assembly 61 is on top and the driving backplate 62 is on the bottom. Figure 6 (b) In addition, the LED chip 13 in the LED chip assembly 61 should be aligned with the chip receiving area 620 on the driving backplane 62. Taking the LED chip 13 as a flip-chip structure as an example, the chip electrode of the LED chip 13 should be aligned with the backplane electrode on the driving backplane 62. This ensures that the LED chip 13 falls directly into the chip receiving area 620 after detaching from the patterned support layer 12. This avoids the need for subsequent adjustments to the position of the LED chip 13 on the driving backplane 62 and ensures that the LED chip 13 can be successfully bonded in the chip receiving area 620. This not only simplifies the transfer bonding process of the LED chip 13 but also improves the transfer bonding yield of the LED chip 13.

[0069] It is understandable that the through-hole 110 in the patterned substrate 11 can limit the horizontal displacement of the LED chip 13 during the process of the LED chip 13 falling to the driving back plate 62, preventing the LED chip 13 from flipping. However, after the LED chip 13 passes through the through-hole 110, there may be displacement or flipping. Therefore, in this embodiment, after aligning the LED chip assembly 61 with the driving back plate 62, the side of the LED chip assembly 61 facing the driving back plate 62 can be directly attached to the driving back plate 62. In this way, the LED chip 13 does not even need to pass through the through-hole 110 before it falls onto the driving back plate 62, and there is no chance of displacement or flipping.

[0070] S506: The control unit extends from the cutout of the patterned support layer, presses against the back side of the LED chip, and applies pressure to the LED chip until the LED chip falls into the chip receiving area.

[0071] After the relative positions of the drive backplate 62 and the LED chip assembly 61 are set, the operating body 63 can be controlled to extend into the patterned support layer 12 through the cutout. Undoubtedly, because the patterned support layer 12 is located on the side of the LED chip 13 away from the back surface, the operating body extending from the cutout can only abut against the side of the LED chip 13 away from the back surface. Figure 6 (c) After touching the back side of the LED chip 13, the operating body 63 can apply pressure to the LED chip 13, such as... Figure 6 In step (d), the LED chip moves away from the patterned support layer 12, thereby detaching from the patterned support layer 12 and falling onto the chip receiving area 620 on the driving backplate 61, whereby the driving backplate 61 provides a supporting force to the LED chip 13 to balance its gravity.

[0072] S508: Bond the LED chip in the chip receiving area to the driver backplane to obtain the display panel.

[0073] After the LED chip 13 falls onto the chip receiving area 620 of the driver backplane 62, the LED chip 13 can be bonded to the driver backplane 62, such as... Figure 6 In section (e), it can be understood that bonding the LED chip 13 to the driving backplane 62 includes both fixing the LED chip 13 onto the driving backplane 62 to achieve a physical connection between the LED chip 13 and the driving backplane 62, and achieving an electrical connection between the LED chip 13 and the driving backplane 62. Taking the LED chip 13 as a flip-chip LED, in this embodiment, before peeling the LED chip 13 from the LED chip assembly 61, bonding material can be first applied to the backplane electrode of the driving backplane 62 or the chip electrode of the LED chip 13. This way, when the LED chip 13 falls onto the driving backplane 62, bonding can be directly achieved. Optionally, the bonding material includes, but is not limited to, solder, such as gold-tin alloy, solder, etc., and may also include conductive adhesives, such as conductive silver paste, ACF (anisotropic conductive film), etc.

[0074] Understandably, multiple LED chips 13 in an LED chip assembly 61 can be simultaneously peeled onto the driving backplate 62. For example, multiple ejector pins can simultaneously eject different LED chips 13, which can improve the transfer bonding efficiency of the LED chips 13. Furthermore, defective LED chips 13 bonded to the driving backplate 62 are common. Therefore, after bonding the LED chips 13 to the driving backplate 62, defective LED chips on the driving backplate 62 can be detected and removed. Then, a repair LED chip assembly is provided. This assembly can also be the LED chip assembly 10 provided in the previous example. After aligning the repair LED chip assembly with the driving backplate 62, the operating body can be controlled to eject the corresponding LED chip from the repair LED chip assembly based on the position of the defective LED chip in the driving backplate 62. After the repair LED chip is ejected onto the driving backplate 62, these LED chips can be bonded to the driving backplate 62 to achieve LED chip repair. Of course, defective LED chips may still exist after repair, so testing and repair need to continue until there are no defective LED chips on the driver backplane 62. Undoubtedly, during the LED chip repair process, the operating body will not apply pressure to other LED chips in the LED chip assembly used for repair, except for the LED chip being repaired.

[0075] In the LED chip assembly and display panel manufacturing method provided in this embodiment, since the LED chip is supported in the through-hole only by a patterned support layer in the LED chip assembly, when it is necessary to manufacture the display panel, it is only necessary to align the LED chip assembly with the driving backplate and push the LED chip down using an operating body such as a push pin, so that the LED chip can fall into the chip receiving area of ​​the driving backplate. Moreover, because the limiting block of the through-hole can prevent the LED chip from shifting or flipping during the transfer to the driving backplate, it not only improves the transfer efficiency of the LED chip, but also increases the transfer yield and reduces the manufacturing cost of the display panel.

[0076] Another optional embodiment of this application:

[0077] This embodiment provides a method for preparing the LED chip assembly described in the foregoing embodiments. Please refer to [link to previous document]. Figure 7 and Figure 8 :

[0078] S702: Provides a carrier substrate with multiple LED chips and a temporary transfer substrate with multiple grooves.

[0079] Please see Figure 8In embodiment (a), multiple LED chips 13 are disposed on the carrier substrate 81, and the back side of the LED chips 13 faces the carrier substrate. That is, the orientation of the LED chips 13 on the carrier substrate 81 is opposite to its orientation on the driving backplane. Taking a flip-chip LED as an example, when the flip-chip LED is located on the driving backplane, its chip electrodes face the driving backplane, but when the flip-chip LED is located on the carrier substrate 81, its chip electrodes face away from the carrier substrate 81. In this embodiment, the carrier substrate 81 can be the growth substrate of the LED chips 13. For example, when the LED chips 13 are blue or green chips, the carrier substrate 81 can be a sapphire substrate, silicon substrate, or GaN (gallium nitride) substrate on which the blue-green epitaxial layer is grown. Of course, in this embodiment, it is also possible that the carrier substrate 81 is only a substrate used to temporarily support the LED chips 13 after the LED chips 13 have been grown, i.e., a transient substrate (also called a "temporary substrate", "transfer substrate", etc.).

[0080] The temporary transfer substrate 82 has multiple grooves 820, which are essentially non-penetrating "blind holes" relative to the temporary transfer substrate 82. In this embodiment, the temporary transfer substrate 82 includes a temporary substrate 821 and a patterned substrate 11 with multiple through-holes 110, which are stacked on top of each other. When the upper surface of the temporary substrate 821 is opposite to the lower surface of the patterned substrate 11 and there is no gap between them, the lower end of the through-hole 110 is sealed by the surface of the temporary substrate 821, thereby forming a groove 820. It should be understood that since the temporary transfer substrate 82 is formed by combining the independent temporary substrate 821 and the patterned substrate 11, the temporary substrate 821 and the patterned substrate 11 in the temporary transfer substrate 82 can also be separated from each other when needed.

[0081] In some examples of this embodiment, the temporary transfer substrate 82 also includes a bonding layer 822; please refer to [link to relevant documentation]. Figure 9 The diagram shown illustrates a process state change during the fabrication of the temporary transfer substrate 82: Figure 9 In (a), a temporary substrate 821 and a patterned substrate 11 are provided. Subsequently, as... Figure 9 In (b) of this embodiment, the two are aligned and then bonded together by a bonding layer 822 between them. In some examples of this embodiment, the bonding layer 822 may be pre-formed on another substrate and then transferred to the side of the temporary substrate 821 facing the patterned substrate 11 or to the side of the patterned substrate 11 facing the temporary substrate 821; in other examples, the bonding layer 822 may be temporarily formed on the side of the temporary substrate 821 facing the patterned substrate 11 or on the side of the patterned substrate 11 facing the temporary substrate 821.

[0082] In some examples of this embodiment, the temporary substrate 821 and the patterned substrate 11 can be bonded together by adhesive bonding. Therefore, the bonding layer 822 can be a bonding adhesive layer, such as a BCB (benzocyclobutene) adhesive layer, a pyrolytic adhesive layer, etc. For example, a bonding adhesive layer is provided on the side of the temporary substrate 821 facing the patterned substrate 11, and the bonding adhesive layer is used to fix the patterned substrate 11 to the temporary substrate 821. In some examples, the surface morphology of the bonding adhesive layer is consistent with the surface morphology of the patterned substrate 11, that is, there is a cutout at the position where the bonding adhesive layer is opposite to the through-hole 110 in the patterned substrate 11. In other examples, the surface morphology of the bonding adhesive layer is consistent with the surface morphology of the temporary substrate 821, and there is no cutout. For example, in Figure 9 As shown in (b), the bonding adhesive layer will also be exposed at the bottom of the groove 820. In other examples of this embodiment, other methods can also be used to bond the temporary substrate 821 to the patterned substrate 11, such as eutectic bonding, van der Waals force bonding, etc.

[0083] S704: Bonding blocks are set on the front and back sides of the LED chip.

[0084] After obtaining the carrier substrate 81 with multiple LED chips 13, bonding blocks 823 can be set on the front and back sides of the LED chips 13, such as... Figure 8 In (b), the bonding block 823 is mainly used to bond the LED chip 13 on the carrier substrate 81 to the bottom of the groove 820 of the temporary transfer substrate 82, so that after the carrier substrate 81 is peeled off, the LED chip 13 can be stably placed in the groove 820 without the support of the carrier substrate 81.

[0085] In some examples of this embodiment, the bonding block can be an adhesive block, such as a BCB adhesive block, so that the bonding block 823 can bond and fix the LED chip 13 to the bottom of the groove 820. When setting the bonding block 823, liquid adhesive can be applied to the front and back sides of the LED chip 13. After the liquid adhesive cures, the bonding block 823 bonded to the front and back sides of the LED chip 13 can be formed.

[0086] Understandably, in some examples, the bottom of the groove 820 is provided with a bonding adhesive layer. Therefore, even if the bonding block 823 itself is not adhesive, it is still feasible as long as the bonding block 823 is attached to the LED chip 13 and can contact the bonding adhesive layer at the bottom of the groove 820. This is because the bonding adhesive layer can be bonded to the bonding block 823, thereby fixing the LED chip 13, which is fixed together with the bonding block 823, in the groove 820.

[0087] S706: After aligning the carrier substrate with the patterned substrate, place at least part of the LED chip in the through hole until the bonding block is bonded to the bottom of the groove.

[0088] After the bonding blocks 823 are disposed on the front and back sides of the LED chip 13, the carrier substrate 81 can be aligned with the patterned substrate 11, with the front and back sides of the LED chip 13 facing the bottom of the groove 820, as shown. Figure 8 As shown in (c). The carrier substrate 81 and the temporary transfer substrate 82 can then continue to move relative to each other until the bonding block 823 is bonded to the bottom of the groove 820, as shown in (c). Figure 8 (d) in the middle.

[0089] S708: After removing the carrier substrate, a patterned support layer is provided on the side of the patterned substrate away from the temporary substrate.

[0090] After the LED chip 13 on the carrier substrate 81 is bonded to the bottom of the groove 820 by the bonding block 823, the carrier substrate 81 can be removed. Figure 8 As shown in (e) in the figure. In some examples, LLO (laser lift-off) can be used to separate the LED chip 13 from the carrier substrate 81. For example, if the LED chip 13 is a GaN-based chip and the carrier substrate 81 is the growth substrate of the LED chip 13, then when peeling off the carrier substrate 81, the interface between the carrier substrate 81 and the LED chip 13 is irradiated with a laser, causing the GaN→Ga+N2 reaction to occur at the interface, thereby destroying the bond between the carrier substrate 81 and the LED chip 13 and removing the carrier substrate 81.

[0091] After removing the carrier substrate 81, a patterned support layer 12 can be formed on the side of the patterned substrate 11 away from the temporary substrate 821, such as... Figure 8 (f) In this context, a patterned support layer 12 is provided on the side of the LED chip 13 away from the back side. The patterned support layer 12 is not only attached to the patterned substrate 11, but also adheres to the LED chip 13. In this way, the patterned support layer 12 can fix the LED chip 13 in the position of the through hole 110 from the front and back sides of the LED chip 13, thereby ensuring that after the support of the temporary transfer substrate 82 is removed, the LED chip 13 can continue to be held in the same position in the through hole 110 as before the temporary transfer substrate 82 was removed.

[0092] As the name suggests, the patterned support layer 12 is a patterned layer structure. In this embodiment, the patterning of this layer structure is required mainly because at least a portion of the LED chip 13 facing away from the patterned support layer 12 must be exposed. That is, the patterned support layer 12 must not completely cover the back side of the LED chip 13, so that the external operating object can directly touch the back side of the LED chip 13 in subsequent processes. Therefore, in this embodiment, the patterned support layer 12 and the LED chip 13 are cut out at the positions opposite to the back side.

[0093] As described in the foregoing embodiments, the cutout areas 100a of different LED chips 13 on the patterned support layer 12 can be interconnected, for example, please refer to... Figure 10a The diagram shows a top view of an LED chip assembly 10a. Additionally, in some other examples, the cutout areas 100b of different LED chips 13 on the patterned support layer 12 can also be independent of each other, such as... Figure 10b The LED chip assembly 10b is shown. With the cutout areas being independent of each other, the patterned support layer 12 has an operation hole 120 corresponding to the position of each LED chip 13 from the back side. The operation hole 120 is used for an operating body to extend into and apply pressure to the LED chip 13 to push the LED chip 13 down.

[0094] In this embodiment, the patterned support layer 12 is a brittle material, such as silicon oxide or a brittle metal. In other examples of this embodiment, the patterned support layer 12 may also be a relatively brittle adhesive material after curing. In some examples, the support material forming the patterned support layer 12 can be deposited on the patterned substrate 11 by methods such as PVD (Physical Vapor Deposition), CVD (Chemical Vapor Deposition), or EV (vacuum evaporating).

[0095] Understandably, to obtain a patterned layer structure, a support material can first be deposited on the side of the patterned substrate 11 facing away from the temporary substrate 821 to form a complete support layer. Then, the support layer is patterned by etching to create a cutout at the position opposite the back side of the LED chip 13, thereby obtaining the patterned support layer 12. This method of setting the patterned support layer 12 is more suitable for scenarios where silicon oxide is used as the support material. This is because if the support layer is made of metal, the etching temperature of the metal may exceed the temperature that the epitaxial layer of the LED chip 13 can withstand during the etching process, which could lead to damage to the LED chip 13 during the patterning process.

[0096] In other examples of this embodiment, when setting the patterned support layer 12, a mask pattern can be set first, covering at least a portion of the LED chip away from the back surface. Then, the support material is set through the mask pattern. Because of the protection of the mask pattern, some areas of the LED chip 13 away from the back surface are not covered by the support material. Therefore, the patterned support layer 12 can be obtained after removing the mask pattern. This method of setting the patterned support layer 12 is suitable for scenarios where metal is used as the support material, as it avoids the problem of damaging the LED chip 13 by etching the support layer at a high temperature after depositing the metal material. As for scenarios where silicon oxide is used as the support material, this method is usually not chosen because the mask pattern cannot withstand the excessively high deposition temperature of silicon oxide. However, those skilled in the art will understand that currently common mask patterns are formed using photoresist, but if other high-temperature resistant mask materials can be found, the patterned support layer 12 made of silicon oxide can also be set in this way.

[0097] S710: Remove the temporary substrate and bonding block to obtain the LED chip assembly.

[0098] After the patterned support layer 12 is applied, the temporary substrate 821 and the bonding block 823 can be removed. Since the temporary substrate 821 is bonded to the patterned substrate 11, removing the temporary substrate 821 requires first disrupting the connection between the temporary substrate 821 and the patterned substrate 11, allowing the temporary substrate 821 to separate from the patterned substrate 11. In some examples of this embodiment, the temporary substrate 821 is bonded to the patterned substrate via a bonding adhesive layer (e.g., a pyrolytic adhesive layer or a BCB adhesive layer). Heating can reduce the adhesive strength of the bonding adhesive layer, thereby causing the temporary substrate 821 to detach. Figure 8 As shown in (g) in the diagram. For bonded block 823, it can be removed by etching, laser engraving, etc., such as... Figure 8 (h) After removing the temporary substrate 821 and the bonding block 823, the LED chip assembly 10 can be obtained.

[0099] It is understood that the patterned substrate 11 in the LED chip assembly 10 can be recycled. For example, after all the LED chips 13 in an LED chip assembly 10 have been peeled off, the patterned support layer 12 attached to the patterned substrate 11 can be removed, and then the patterned substrate 11 can be used to prepare a new temporary transfer substrate, thereby forming a new LED chip assembly. This can reduce the manufacturing cost of the LED chip assembly 10.

[0100] The LED chip assembly fabrication method provided in this embodiment utilizes a temporary substrate and a patterned substrate to form a temporary transfer substrate with multiple grooves. Simultaneously, bonding blocks are disposed on the front and back sides of the LED chip. After aligning the carrier substrate and the patterned substrate, the LED chip is at least partially placed in the through-hole until the bonding blocks are bonded to the bottom of the grooves. Therefore, even after the carrier substrate is peeled off, the bonding blocks can still support the LED chip in the through-hole. In this case, a patterned support layer is disposed on the side of the patterned substrate away from the temporary substrate. This patterned support layer adheres not only to the patterned substrate but also to the LED chip. Therefore, after removing the temporary transfer substrate and the bonding blocks, the patterned support layer can provide a force to the LED chip to balance its weight, allowing the LED chip to continue to be suspended and held in the through-hole. Meanwhile, the exposed position of the patterned support layer relative to the back side of the LED chip ensures that during the transfer of the LED chip to the driver backplane, the external operating body can extend through the cutout and touch the LED chip, applying pressure to it. This pressure causes the LED chip to detach from the patterned support layer and fall through the through-hole on the patterned substrate. Therefore, during the transfer of the LED chip from the LED chip assembly to the driver backplane, simply aligning the LED chip assembly with the driver backplane and ensuring the front and back sides of the LED chip face the driver backplane guarantees that the LED chip will fall directly into the chip receiving area of ​​the driver backplane under the pressure of the operating body. The transfer process is simple and convenient, and with multiple operating bodies working simultaneously, multiple LED chips can be transferred to the driver backplane at the same time, improving the transfer efficiency of the LED chips. In addition, the process of the LED chip falling is actually the process of the LED chip passing through the through hole. When the LED chip passes through the through hole, its horizontal movement is restricted by the side wall of the through hole. This can be achieved by using the side wall of the through hole to limit the horizontal displacement of the LED chip during the falling process, reducing the displacement and flipping of the LED chip, improving the accuracy of the LED chip transfer position, and improving the transfer yield of the LED chip.

[0101] Another optional embodiment of this application:

[0102] To provide those skilled in the art with a clearer understanding of the details and advantages of the aforementioned LED chip components and their fabrication methods, as well as the display panel fabrication methods, this embodiment will continue to illustrate the fabrication and application of LED chip components with examples. Please refer to [link to relevant documentation]. Figure 11 and Figure 12 :

[0103] S1102: Provide a growth substrate and an epitaxial layer grown on the growth substrate.

[0104] In this embodiment, the epitaxial layer 1202 can be a GaN-based blue-green epitaxial layer, and the growth substrate 1201 is a sapphire substrate. For example... Figure 12 In (a), the epitaxial layer 1202 is deposited on the growth substrate 1201 and includes, from bottom to top, an N-type semiconductor layer (such as an N-GaN layer), an active layer, and a P-type semiconductor layer (such as a P-GaN layer). It is understood that the epitaxial layer 1202 is not limited to these three layers. In addition, it may include at least one of the following layer structures: a buffer layer, a stress relief layer, and an ohmic contact layer.

[0105] S1104: Multiple LED chips fabricated based on epitaxial layers.

[0106] like Figure 12 In (b) above, after obtaining the growth substrate 1201 with the epitaxial layer 1202, multiple LED chips 1206 can be fabricated based on the epitaxial layer 1202. The process of fabricating LED chips 1206 is described below:

[0107] exist Figure 13 In (b), for Figure 13 The epitaxial layer 1202 provided in (a) is subjected to mesa etching, the etching method is dry etching, and the etching gas can be at least one of BCl3 (boron trichloride) and Cl2 (chlorine).

[0108] exist Figure 13 In step (c), trench etching is continued on the epitaxial layer 1202 until the growth substrate 1201 is exposed. The etching method can also be dry etching, and the etching gas can be at least one of BCl3 and Cl2.

[0109] exist Figure 13 In step (d), an ITO (indium tin oxide) layer with a thickness of 200 to 2000 Å can be sputtered on the epitaxial layer 1202; then a mask pattern is formed on the ITO layer using photoresist, and the ITO layer is wet-etched under the protection of the mask pattern and the photoresist is removed to obtain the ITO pattern 1203.

[0110] exist Figure 13 In (e), silicon oxide and silicon nitride are vapor-deposited on ITO pattern 1203 to form DBR (Distributed Bragg Reflection), with a thickness of 1-4 μm; then a mask pattern is formed on the DBR using photoresist; subsequently, the DBR is dry-etched using at least one of several etching gases such as CF4 (carbon tetrafluoride), O2 (oxygen), and Ar (argon) until the DBR is etched through; after removing the mask pattern, DBR pattern 1204 is obtained.

[0111] exist Figure 13In step (f), a mask pattern is formed on the DBR pattern 1204 using negative photoresist. This mask pattern is used to set the PADs (chip electrodes) of the LED chip 1206. Subsequently, electrode materials are deposited using an electrode deposition machine, such as a Fuller evaporation machine, to form an electrode layer with a thickness of 1–4 μm. After peeling off the blue film and removing the photoresist, the chip electrode 1205 is obtained, thus completing the fabrication of the LED chip 1206.

[0112] S1106: A temporary transfer substrate is made from a temporary substrate and a patterned substrate.

[0113] In this embodiment, both the temporary substrate 1207 and the patterned substrate 1208 can be formed from sapphire substrate, glass substrate, silicon substrate, etc. The patterned substrate 1208 is provided with a plurality of through holes 1209 arranged in an array. The arrangement of the through holes 1209 on the patterned substrate 1208 is the same as the arrangement of the LED chips 1206 on the growth substrate 1201. Typically, the cross-sectional size of the through holes 1209 is slightly larger than the cross-sectional size of the LED chips 1206, for example, 2 to 5 μm larger.

[0114] Please see Figure 12 In (c), the horizontal dimensions of the patterned substrate 1208 and the temporary substrate 1207 can be the same. For example, in one embodiment, both the temporary substrate 1207 and the patterned substrate 1208 are 4 inches. The temporary substrate 1207 and the patterned substrate 1208 can be bonded together using a BCB bonding adhesive layer 1210. In this embodiment, the BCB bonding adhesive layer 1210 can be coated on one surface of the temporary substrate 1207, and then the patterned substrate 1208 and the BCB bonding adhesive layer 1210 are bonded together, thereby achieving the bonding of the patterned substrate 1208 and the temporary substrate 1207. After the patterned substrate 1208 and the temporary substrate 1207 are bonded, the temporary transfer substrate is fabricated. Figure 12 (c) in the middle. From Figure 12 As can be seen in (c), the through-hole 1209 becomes a groove after the patterned substrate 1208 and the temporary substrate 1207 are bonded, and the bottom of the groove has a BCB bonding adhesive layer 1210 exposed.

[0115] S1108: BCB adhesive is deposited on the chip electrode side of the LED chip on the growth substrate to form a BCB bonding block.

[0116] After fabricating the LED chip 1206 on the growth substrate 1201, bonding blocks can be disposed on the front and back sides of the LED chip 1206. Since the LED chip 1206 in this embodiment is a flip-chip structure, the bonding blocks are disposed on the chip electrode side of the LED chip 1206. Furthermore, in this embodiment, the bonding blocks are formed using BCB adhesive. Specifically, liquid BCB adhesive can be coated on the side of the LED chip 1206 away from the growth substrate 1201 to form a BCB bonding block 1211, such as... Figure 12 (d) in the middle.

[0117] It is understood that the process of setting the BCB bonding block 1211 on the front and back sides of the LED chip 1206 can be completed immediately after the LED chip 1206 is manufactured, or it can be performed after the temporary transfer substrate is prepared. Those skilled in the art will understand that there is no strict timing between the process of setting the BCB bonding block 1211 and the process of preparing the temporary transfer substrate.

[0118] S1110: Bonding the LED chip on the growth substrate to the temporary transfer substrate.

[0119] Subsequently, the growth substrate 1201 can be aligned with the temporary transfer substrate, and the LED chip can be inserted at least partially into the through-hole 1209 until the BCB bonding block 1211 and the BCB bonding adhesive layer 1210 are bonded together, as follows. Figure 12 (e) in the middle.

[0120] S1112: Substrate grown by laser lift-off.

[0121] After the LED chip 1206 is bonded into the groove, the substrate 1201 can be grown using laser lift-off, such as... Figure 12 As shown in (f) in the figure.

[0122] S1114: Deposit a SiO2 layer on the side of the patterned substrate away from the temporary substrate.

[0123] After the growth substrate 1201 is stripped, the side of the patterned substrate 1208 furthest from the temporary substrate 1207 is exposed. At this point, a SiO2 layer 1212 can be deposited using PECVD (Plasma Enhanced Chemical Vapor Deposition). The SiO2 layer 1212 will simultaneously adhere to the exposed surface of the LED chip 1206 furthest from the temporary substrate 1207 on the back side of the previous patterned substrate 1208. Figure 12 In some cases, the SiO2 layer 1212 may also be embedded in the through-hole 1209.

[0124] S1116: The SiO2 layer is etched to create operation holes to obtain a patterned SiO2 layer.

[0125] because Figure 12 (g) The SiO2 layer 1212 completely covers the side of the patterned substrate 1208 away from the temporary substrate 1207, causing the back side of the LED chip 1206 to be entirely below the SiO2 layer 1212. To expose at least a portion of the back side of the LED chip 1206, in this embodiment, the SiO2 layer 1212 is etched to create an operation hole 1213 at a position opposite to the back side of the LED chip 1206. Please refer to [link to documentation]. Figure 12 (h) The aperture of the operating hole 1213 is usually small, but it can allow operating elements such as ejector pins to pass through. Dry etching can be used when etching the SiO2 layer 1212, and the etching gas includes, but is not limited to, silane and nitrous oxide.

[0126] It is understood that in some other examples of this embodiment, a metal layer can be used instead of the SiO2 layer 1212. However, if a metal layer is set, a mask pattern should be set before depositing the metal material to avoid etching after the metal layer is set.

[0127] S1118: Heating causes the temporary substrate to detach from the BCB adhesive.

[0128] After the patterned SiO2 layer 1212 is formed, the temporary substrate 1027 can be peeled off. In this embodiment, heating can reduce the adhesive strength of the BCB adhesive, thereby allowing the temporary substrate 1207 to detach from the BCB adhesive layer. Figure 12 (i) in the middle.

[0129] S1120: Etching to remove BCB adhesive.

[0130] The BCB adhesive attached to the patterned substrate 1208 and the LED chip 1206 also needs to be removed in this embodiment. Optionally, the BCB adhesive can be removed by dry etching, such as... Figure 12 (j) After the BCB adhesive is removed, the LED chip assembly 1214 is fabricated.

[0131] S1122: Align the driver backplane with the LED chip assembly, with the front and back faces of the LED chip facing and opposite the chip receiving area of ​​the driver backplane.

[0132] After the LED chip assembly 1214 is fabricated, it can be applied: the structure of the LED chip assembly 1214 is used to quickly and accurately transfer the LED chip 1206 onto the driving backplane. Optionally, the driving backplane 1215 can be aligned with the LED chip assembly 1214, keeping the front and back faces of the LED chip 1206 opposite to the chip receiving area of ​​the driving backplane 1215, such as... Figure 12 (k) in the middle.

[0133] S1124: The control body extends into the operation hole, presses against the back side of the LED chip, and applies pressure to the LED chip until the LED chip falls into the chip receiving area.

[0134] Subsequently, an operating body, such as a pin 1216, is inserted into the operating hole 1213, pressed against the back side of the LED chip 1206, and pressure is applied to the LED chip 1206 until the LED chip 1206 detaches from the SiO2 layer 1212 and falls into the chip receiving area of ​​the driving backplate 1215. Figure 12 (l) in the middle.

[0135] It is understandable that in the flip-chip LED chip 1206, the area away from the back side may be larger than the area facing the back side. Therefore, the epitaxial layer of the LED chip 1206 is shaped like an inverted trapezoid. In this case, when the LED chip 1206 falls off the SiO2 layer 1212, the SiO2 layer 1212 will break. Part of it will adhere to the LED chip 1206 and be carried away by the LED chip 1206. However, since the SiO2 layer can passivate the LED chip 1206, it will not have a negative impact on the performance of the LED chip 1206.

[0136] S1126: Bond the LED chip in the chip receiving area to the driver backplane to obtain the display panel.

[0137] After the LED chip 1206 is placed on the driver backplane 1215, the chip electrodes of the LED chip 1206 can be bonded to the backplane electrodes on the driver backplane 1215, thereby realizing the transfer of the LED chip 1206, such as... Figure 12 (m) in the middle.

[0138] Understandably, the LED chips 1206 transferred to the driver backplane 1215 can be of different colors in order to produce a colored display panel.

[0139] In this embodiment, a patterned substrate and a patterned support layer are used to enable the rapid transfer of a large number of LED chips, improving the transfer efficiency. Simultaneously, the through-holes in the patterned substrate prevent the LED chips from shifting or flipping during their journey onto the driver backplane, thus improving the transfer yield. Furthermore, the reusable patterned substrate reduces the manufacturing cost of the display panel.

[0140] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. An LED chip assembly, characterized in that, include: A patterned substrate with multiple through-holes; A patterned support layer disposed on one side of the patterned substrate and bonded to the patterned substrate; as well as Multiple LED chips, at least partially inserted into the through-hole; The LED chip is partially embedded in the patterned support layer, with its front side facing away from the patterned support layer. A cutout is made in the patterned support layer at a position opposite to the back side of the LED chip, allowing an operating body to extend through the cutout and touch the LED chip. Pressure is applied to the LED chip to detach it from the patterned support layer and allow it to exit through the through-hole. The front side and the back side are respectively the side of the LED chip facing the drive backplate and the side facing away from the drive backplate when the LED chip is fixed to the drive backplate.

2. The LED chip assembly as described in claim 1, characterized in that, The patterned support layer and the LED chip are provided with hollowed-out operation holes at positions opposite to the back side.

3. The LED chip assembly as described in claim 1, characterized in that, The patterned support layer includes either silicon oxide or a metal.

4. The LED chip assembly as described in any one of claims 1-3, characterized in that, The distance between the side of the patterned substrate away from the patterned support layer and the front and back sides of the LED chip is greater than the height of the LED chip.

5. A method for fabricating an LED chip assembly, characterized in that, Application to the fabrication of the LED chip assembly as described in any one of claims 1-4, comprising: A carrier substrate with multiple LED chips and a temporary transfer substrate with multiple grooves are provided. The temporary transfer substrate includes an overlapping temporary substrate and a patterned substrate with multiple through holes. The grooves are formed by the through holes. A bonding block is provided on the front and back sides of the LED chip. The front and back sides are the side of the LED chip facing the driving back plate when the LED chip is fixed on the driving back plate, and the front and back sides of the LED chip face away from the carrier substrate. After aligning the carrier substrate with the patterned substrate, the LED chip is placed at least partially in the through-hole until the bonding block is bonded to the bottom of the groove. After removing the carrier substrate, a patterned support layer is provided on the side of the patterned substrate away from the temporary substrate. The patterned support layer is attached to the patterned substrate and the LED chip, and the patterned support layer and the LED chip are cut out at positions opposite to the back side. The temporary substrate and the bonding block are removed to obtain the LED chip assembly.

6. The method for preparing an LED chip assembly as described in claim 5, characterized in that, The bonding blocks on the front and back sides of the LED chip include: A liquid adhesive is coated on both sides of the LED chip; After the liquid adhesive material cures, it forms a bonding block that adheres to the front and back sides of the LED chip.

7. The method for preparing an LED chip assembly as described in claim 6, characterized in that, A temporary transfer substrate with multiple grooves is provided, including: Provide a temporary substrate and a patterned substrate; The patterned substrate and the temporary substrate are aligned and then bonded together by a bonding layer between them.

8. The method for preparing an LED chip assembly as described in claim 7, characterized in that, The bonding layer is a bonding adhesive layer with an area greater than or equal to that of the patterned substrate and without any perforations; the step of placing at least a portion of the LED chip in the through-hole until the bonding block is bonded to the bottom of the groove includes: Apply pressure toward each other to at least one of the carrier substrate and the temporary substrate until the bonding block is bonded to the bonding adhesive layer at the bottom of the groove.

9. The method for preparing an LED chip assembly as described in any one of claims 5-8, characterized in that, The provision of a patterned support layer on the side of the patterned substrate away from the temporary substrate includes any one of the following: A mask pattern is provided that covers at least a portion of the LED chip away from the back surface; The patterned support layer is formed by depositing a support material through the mask pattern; Remove the mask pattern; A support material is deposited on the side of the patterned substrate facing away from the temporary substrate to form a support layer; the support layer is patterned so that the support layer and the LED chip are cut out at positions opposite to the back side.

10. A method for manufacturing a display panel, characterized in that, include: Provides a driver backplane and an LED chip assembly as described in any one of claims 1-4; The driving backplate is aligned with the LED chip assembly, with the front and back faces of the LED chip facing and opposite to the chip receiving area of ​​the driving backplate; The control unit extends from the cutout of the patterned support layer, abuts against the back side of the LED chip, and applies pressure to the LED chip until the LED chip falls into the chip receiving area; The LED chip in the chip receiving area is bonded to the driving backplane to obtain the display panel.

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