Transfer substrate, preparation method of transfer substrate, and transfer method

Abstract

The present application provides a transfer substrate, a preparation method of the transfer substrate, and a transfer method. In a first aspect of the present application, a transfer substrate is provided for transferring a light-emitting diode chip from a growth substrate to a driving backplane, including: a substrate; a sacrificial layer disposed on the substrate; a chip transfer layer disposed on a side of the sacrificial layer facing away from the substrate, the chip transfer layer including a chip layer and a counterweight layer arranged in a stacked manner, wherein the chip layer includes a plurality of light-emitting diode chips arranged at intervals, the counterweight layer includes a plurality of counterweight portions arranged at intervals, the counterweight portions are in one-to-one contact with the light-emitting diode chips, and the counterweight portions are used to be transferred to the driving backplane together with the light-emitting diode chips. The arrangement of the counterweight portions improves the transfer accuracy of the light-emitting diode chips.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and particularly relates to a transfer substrate, a preparation method of the transfer substrate, and a transfer method. Background Art

[0002] With the development of display technology, light-emitting diode (LED) chips have been widely used in various fields. As a light source, the light-emitting diode chip has many advantages, such as low power consumption, long service life, and fast switching speed, etc. In addition to being used as a light source, mini light-emitting diode (Mini LED) chips and micro light-emitting diode (Micro LED) chips have been widely applied in the field of display technology.

[0003] In the preparation of display panels with Mini LED and Micro LED, the laser transfer technology can effectively improve the transfer efficiency and repair efficiency of light-emitting diode chips. However, the accuracy of the landing point of the light-emitting diode chip in the laser transfer technology is low, and the problem of the deviation of the Micro / Mini light-emitting diode chip after transfer has a great impact on the display quality and product yield of the display product.

[0004] Therefore, there is an urgent need for a transfer substrate, a preparation method of the transfer substrate, and a transfer method. Summary of the Invention

[0005] A first aspect of the present application provides a transfer substrate for transferring a light-emitting diode chip from a growth substrate to a driving backplane, including: a substrate; a sacrificial layer disposed on the substrate; a chip transfer layer disposed on a side of the sacrificial layer facing away from the substrate, the chip transfer layer including a chip layer and a weight layer arranged in a stacked manner, wherein the chip layer includes a plurality of spaced-apart light-emitting diode chips, the weight layer includes a plurality of spaced-apart weight portions, the weight portions are in one-to-one contact with the light-emitting diode chips, and the weight portions are used to be transferred to the driving backplane together with the light-emitting diode chips.

[0006] For the transfer substrate provided in the first aspect of the present application, since the weight portions increase the overall weight during the transfer of the light-emitting diode chips, the balance during the transfer of the light-emitting diode chips is increased, and the external disturbance during the transfer and the rebound effect when contacting the driving backplane are better resisted. The design of the weight portions can better improve the position accuracy of the transfer of the light-emitting diode chips, reduce the rotation and flip phenomenon of the light-emitting diode chips, thereby improving the transfer accuracy of the light-emitting diode chips, and avoiding the breakage and fragmentation caused by the flipping and mutual collision of the light-emitting diode chips during laser transfer.

[0007] In a possible implementation manner of the first aspect of the present application, the weight layer is in stacked contact with the sacrificial layer, and the light-emitting diode chips are disposed on a side of the weight portions facing away from the sacrificial layer.

[0008] In a possible implementation manner of the first aspect of the present application, the vertical distance K1 from the center of gravity position of the counterweight portion to the contact surface between the counterweight portion and the light-emitting diode chip is less than or equal to the vertical distance K2 from the center of gravity position of the counterweight portion to the contact surface between the counterweight portion and the sacrificial layer.

[0009] In a possible implementation manner of the first aspect of the present application, the chip layer and the sacrificial layer are stacked and in contact with each other, and the counterweight portion is disposed on the side of the light-emitting diode chip facing away from the sacrificial layer.

[0010] In a possible implementation manner of the first aspect of the present application, the counterweight portion is a frustum of a pyramid structure, the upper bottom surface of the counterweight portion is in contact with the light-emitting diode chip, and the lower bottom surface of the counterweight portion faces away from the light-emitting diode chip.

[0011] In a possible implementation manner of the first aspect of the present application, the vertical distance K1 from the center of gravity position of the counterweight portion to the contact surface between the counterweight portion and the light-emitting diode chip is less than or equal to the vertical distance K3 from the center of gravity position of the counterweight portion to the surface of the counterweight portion facing away from the light-emitting diode chip.

[0012] In a possible implementation manner of the first aspect of the present application, in the thickness direction of the transfer substrate, the thickness of the counterweight portion is less than or equal to the thickness of the corresponding light-emitting diode chip.

[0013] In a possible implementation manner of the first aspect of the present application, in the thickness direction of the transfer substrate, the center of gravity of the counterweight portion and the center of gravity of the light-emitting diode chip are on the same vertical line.

[0014] In a possible implementation manner of the first aspect of the present application, the orthographic projection of the counterweight portion on the substrate covers the orthographic projection of the light-emitting diode chip on the substrate.

[0015] In a possible implementation manner of the first aspect of the present application, the electrode side of the light-emitting diode chip where the electrode is provided faces the counterweight portion, or the electrode side of the light-emitting diode chip where the electrode is provided faces away from the counterweight portion.

[0016] The second aspect of the present application provides a method for preparing a transfer substrate, including:

[0017] Forming a pre-counterweight layer on a prefabricated substrate, the prefabricated substrate includes a substrate and a sacrificial layer stacked, the pre-counterweight layer is disposed on the side of the sacrificial layer facing away from the substrate and the pre-counterweight layer is in contact with the sacrificial layer;

[0018] Performing a patterning process on the pre-counterweight layer to form a plurality of counterweight portions arranged in an array, and the plurality of counterweight portions form a counterweight layer, wherein, in the thickness direction of the prefabricated substrate, the counterweight portion is in contact with the corresponding light-emitting diode chip.

[0019] In a possible implementation of the second aspect of the present application, before patterning the pre-counterweight layer, it further includes: transferring the light-emitting diode chips on the growth substrate to the side of the pre-counterweight layer facing away from the sacrificial layer using a temporary transfer substrate, with the electrode side of the light-emitting diode chips facing the pre-counterweight layer, temporarily bonding the light-emitting diode chips to the pre-counterweight layer, and peeling the temporary transfer substrate from the light-emitting diode chips through laser lift-off technology to form a chip layer with multiple light-emitting diode chips.

[0020] The method for preparing the transfer substrate provided in the second aspect of the present application results in a transfer substrate having multiple counterweight portions, which are in contact with the corresponding light-emitting diode chips, so as to increase the overall weight of the light-emitting diode chips during subsequent transfer and improve the accuracy of the transfer position of the light-emitting diode chips.

[0021] The third aspect of the present application provides a transfer method, including:

[0022] Providing a transfer substrate as in the first aspect of the present application;

[0023] Using a laser to peel the sacrificial layer from the chip transfer layer so that the counterweight portions are transferred to the driving backplane together with the light-emitting diode chips.

[0024] The transfer method in the third aspect of the present application has a high transfer accuracy, can prevent situations such as misalignment or tipping of the light-emitting diode chips during the transfer process, improve the position accuracy of the transfer of the light-emitting diode chips, and thus improve the product yield and display quality of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] By reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, other features, objects, and advantages of the present invention will become more apparent, wherein the same or similar reference numerals represent the same or similar features, and the drawings are not drawn to actual scale.

[0026] Figure 1 It is a schematic diagram of the layer structure of an embodiment of the transfer substrate provided in the first aspect of the present application;

[0027] Figure 2 It is a schematic diagram of the layer structure of another embodiment of the transfer substrate provided in the first aspect of the present application;

[0028] Figure 3 It is a schematic diagram of the layer structure of still another embodiment of the transfer substrate provided in the first aspect of the present application;

[0029] Figure 4 It is a flowchart of a method of an embodiment in the method for preparing the transfer substrate provided in the second aspect of the present application;

[0030] Figure 5It is a flowchart of another embodiment in the method for preparing a transfer substrate provided in the second aspect of the present application;

[0031] Figure 6 It is a manufacturing process diagram of another embodiment in the method for preparing a transfer substrate provided in the second aspect of the present application;

[0032] Figure 7 It is a flowchart of still another embodiment in the method for preparing a transfer substrate provided in the second aspect of the present application;

[0033] Figure 8 It is a manufacturing process diagram of still another embodiment in the method for preparing a transfer substrate provided in the second aspect of the present application;

[0034] Figure 9 It is a flowchart of an embodiment in the transfer method provided in the third aspect of the present application.

[0035] In the figure:

[0036] Transfer substrate - 1; Substrate - 11; Sacrificial layer - 12; Chip transfer layer - 13; Chip layer - 131;

[0037] Light - emitting diode chip - 1311; First electrode - a; Second electrode - b; Epitaxial layer - c;

[0038] Counterweight layer - 132; Counterweight portion - 1321; Pre - counterweight layer - 21; Temporary transfer substrate - 4. Detailed implementation manners

[0039] The features and exemplary embodiments of each aspect of the present invention will be described in detail below. To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without some of these specific details. The following description of the embodiments is only for providing a better understanding of the present invention by showing examples of the present invention.

[0040] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0041] In the laser transfer technology, the accuracy of the landing point of the light-emitting diode chip is low, and Micro / Mini light-emitting diode chips often easily exhibit phenomena such as standing on side, rotational misalignment, and flipping. The inventor found during long-term in-depth research that during the laser transfer process, it is necessary to use a laser to strike the contact surface between the sacrificial layer and the light-emitting diode chip on the transfer substrate. After the sacrificial layer absorbs the laser energy, it becomes de-bonded, causing the light-emitting diode chip to separate from the sacrificial layer and fall onto the driving substrate. During the falling process of the light-emitting diode chip, there is a gap between the transfer substrate and the driving substrate. Due to the light weight of the light-emitting diode chip and the influence of external atmosphere disturbance and the rebounding effect of the driving substrate, the light-emitting diode chip is prone to rotational misalignment, standing on side, and flipping after falling onto the driving backplane, resulting in misalignment of the light-emitting diode chip after falling and reducing the accuracy of the landing point of the light-emitting diode chip.

[0042] Based on the discovery and analysis of the above problems, this application is proposed.

[0043] As Figure 1 shown, Figure 1FIG. 0 is a schematic diagram of a layer structure of an embodiment in the transfer substrate provided by the first aspect of the present application. The first aspect of the present application provides a transfer substrate 1 for transferring a light-emitting diode chip 1311 from a growth substrate to a driving backplane, including a substrate 11, a sacrificial layer 12, and a chip transfer layer 13. In some embodiments, the substrate 11 is made of ordinary glass or quartz glass. The sacrificial layer 12 is disposed on the substrate 11. The sacrificial layer 12 contains a photosensitive adhesive, and the photosensitive adhesive absorbs the energy of the laser beam under the action of the laser and detaches from the adhered light-emitting diode chip 1311, so that the light-emitting diode chip 1311 is transferred to the driving backplane. The chip transfer layer 13 is disposed on the side of the sacrificial layer 12 facing away from the substrate 11. The chip transfer layer 13 includes a chip layer 131 and a counterweight layer 132 arranged in a stacked manner. Among them, the chip layer 131 includes a plurality of spaced-apart light-emitting diode chips 1311, and the counterweight layer 132 includes a plurality of spaced-apart counterweight portions 1321. The counterweight portions 1321 are in one-to-one contact with the light-emitting diode chips 1311, and the counterweight portions 1321 are used to be transferred to the driving backplane together with the light-emitting diode chips 1311.

[0044] The first aspect of the present application provides a transfer substrate 1. The counterweight portion 1321 increases the overall weight during the transfer of the light-emitting diode chip 1311, improves the balance during the transfer of the light-emitting diode chip 1311, and better resists external disturbances during the transfer process and the rebound effect when contacting the driving backplane. The design of the counterweight portion 1321 can better improve the position accuracy of the transfer of the light-emitting diode chip 1311, reduce the rotation and flip-chip phenomena of the light-emitting diode chip 1311, and thus improve the transfer accuracy of the light-emitting diode chip 1311.

[0045] In some optional embodiments, the counterweight layer 132 and the sacrificial layer 12 are stacked and in contact with each other, and the light-emitting diode chip 1311 is disposed on the side of the counterweight portion 1321 facing away from the sacrificial layer 12. In these embodiments, the counterweight portion 1321 may include a photosensitive adhesive material, an organic material, etc., such as PDMS (polydimethylsiloxane) material. During the process of laser peeling the chip transfer layer 13, the laser is applied to the contact interface between the counterweight layer 132 and the sacrificial layer 12 to separate the counterweight layer 132 from the sacrificial layer 12. In some examples, the electrode side of the light-emitting diode chip 1311 is disposed facing away from the counterweight layer 132. In these embodiments, the counterweight layer 132 is disposed between the chip layer 131 and the sacrificial layer 12. The design of the counterweight layer 132 can avoid damage to the sacrificial layer 12 and the light-emitting diode chip 1311 by the laser during the process of laser peeling the chip transfer layer 13 from the transfer substrate 1, thereby improving the laser peeling effect.

[0046] In some alternative embodiments, the vertical distance K1 from the center of gravity position of the counterweight portion 1321 to the contact surface between the counterweight portion 1321 and the light-emitting diode chip 1311 is less than or equal to the vertical distance K2 from the center of gravity position of the counterweight portion 1321 to the contact surface between the counterweight portion 1321 and the sacrificial layer 12. In some embodiments, the center of gravity position of the counterweight portion 1321 is closer to the light-emitting diode chip 1311, so that the overall center of gravity of the combination of the light-emitting diode chip 1311 and the corresponding counterweight portion 1321 moves downward. During the process of the counterweight portion 1321 being transferred to the driving backplane together with the light-emitting diode chip 1311, the combination of the light-emitting diode chip 1311 and the corresponding counterweight portion 1321 can fall more quickly and accurately onto the preset position of the driving backplane, avoiding problems such as transfer deviation and flip-chip side-standing of the light-emitting diode chip 1311. The light-emitting diode chip 1311 can be a front-mounted structure or a flip-chip structure. The light-emitting diode chip 1311 includes an epitaxial layer c and a first electrode a and a second electrode b disposed on one side of the epitaxial layer c. In some examples, the electrode side of the light-emitting diode chip 1311 where the electrodes are provided faces away from the counterweight portion 1321. In some other examples, the electrode side of the light-emitting diode chip 1311 where the electrodes are provided faces the counterweight portion 1321, which is not shown in the figure.

[0047] As Figure 2 shown, Figure 2 FIG. is a schematic diagram of the layer structure of another embodiment of the transfer substrate provided in the first aspect of the present application. In some alternative embodiments, the chip layer 131 and the sacrificial layer 12 are stacked and in contact with each other, and the counterweight portion 1321 is disposed on the side of the light-emitting diode chip 1311 facing away from the sacrificial layer 12. In these embodiments, when the chip transfer layer 13 is separated from the sacrificial layer 12 by using a laser transfer technology, after the light-emitting diode chip 1311 and the corresponding counterweight portion 1321 fall onto the driving backplane together, there is no need to set an additional process step to remove the counterweight portion 1321. While improving the transfer accuracy of the light-emitting diode chip 1311, the preparation efficiency of the display panel having the light-emitting diode chip 1311 is improved.

[0048] As Figure 3 shown, Figure 3FIG. 0 is a schematic diagram of a layer structure of still another embodiment of the transfer substrate provided in the first aspect of the present application. In some alternative embodiments, the chip layer 131 and the sacrificial layer 12 are stacked and in contact with each other. The counterweight portion 1321 is disposed on the side of the light-emitting diode chip 1311 facing away from the sacrificial layer 12. The counterweight portion 1321 has a frustum of a pyramid structure. The upper bottom surface of the counterweight portion 1321 is in contact with the light-emitting diode chip 1311, and the lower bottom surface of the counterweight portion 1321 faces away from the light-emitting diode chip 1311. In some examples, the counterweight portion 1321 has a regular frustum of a pyramid structure. In these embodiments, since the counterweight portion 1321 has a frustum of a pyramid structure and the area of the upper bottom surface of the counterweight portion 1321 is smaller than the area of the lower bottom surface, when the whole formed by the light-emitting diode chip 1311 and the counterweight portion 1321 is transferred to the driving backplane, the contact area between the whole formed by the light-emitting diode chip 1311 and the counterweight portion 1321 and the driving backplane increases, and the center of gravity of the whole formed by the light-emitting diode chip 1311 and the counterweight portion 1321 moves downward, further avoiding problems such as side standing and flipping of the light-emitting diode chip 1311 during the transfer process, ensuring that the light-emitting diode chip 1311 is transferred to the driving backplane in an upright posture, and further enhancing the position accuracy of the light-emitting diode chip 1311 after the transfer.

[0049] In some alternative embodiments, the vertical distance K1 from the center of gravity position of the counterweight portion 1321 to the contact surface between the counterweight portion 1321 and the light-emitting diode chip 1311 is less than or equal to the vertical distance K3 from the center of gravity position of the counterweight portion 1321 to the surface of the counterweight portion 1321 facing away from the light-emitting diode chip 1311. In some embodiments, the center of gravity position of the counterweight portion 1321 is closer to the light-emitting diode chip 1311, so that the center of gravity of the whole formed by the light-emitting diode chip 1311 and the corresponding counterweight portion 1321 moves downward. During the process of the counterweight portion 1321 being transferred to the driving backplane together with the light-emitting diode chip 1311, the whole formed by the light-emitting diode chip 1311 and the corresponding counterweight portion 1321 falls on the preset position of the driving backplane more quickly and accurately, avoiding problems such as transfer deviation and flip-chip side standing of the light-emitting diode chip 1311. In some examples, the electrode side of the light-emitting diode chip 1311 where the electrodes are provided faces away from the counterweight portion 1321. In some other examples, the electrode side of the light-emitting diode chip 1311 where the electrodes are provided faces the counterweight portion 1321, which is not shown in the figure.

[0050] In some alternative embodiments, in the thickness direction of the transfer substrate 1, the thickness of the counterweight portion 1321 is less than or equal to the thickness of the corresponding light-emitting diode chip 1311. In some embodiments, the thickness of the counterweight portion 1321 is less than the thickness of the corresponding light-emitting diode chip 1311, which can reduce the thickness of the display panel with the counterweight portion 1321 retained and improve the user experience.

[0051] In some alternative embodiments, in the thickness direction of the transfer substrate 1, the center of gravity of the counterweight portion 1321 and the center of gravity of the light-emitting diode chip 1311 are on the same vertical line. In these embodiments, the center of gravity of the counterweight portion 1321 and the center of gravity of the light-emitting diode chip 1311 being on the same vertical line ensures the alignment of the center of gravity of the light-emitting diode chip 1311 and the corresponding counterweight portion 1321, avoiding the influence on the transfer alignment due to the different center-of-gravity positions of the two, and further improving the accuracy of the transfer of the light-emitting diode chip 1311.

[0052] In some alternative embodiments, the orthographic projection of the counterweight portion 1321 on the substrate 1 covers the orthographic projection of the light-emitting diode chip 1311 on the substrate 1.

[0053] In some alternative embodiments, the electrode side of the light-emitting diode chip 1311 where the electrodes are provided faces the counterweight portion 1321, or the electrode side of the light-emitting diode chip 1311 where the electrodes are provided faces away from the counterweight portion 1321.

[0054] As Figure 4 shown, the second aspect of the present application provides a method for preparing a transfer substrate, including:

[0055] S10, forming a pre-counterweight layer 21 on a prefabricated substrate, the prefabricated substrate including a substrate 11 and a sacrificial layer 12 arranged in a stacked manner, the pre-counterweight layer 21 being provided on the side of the sacrificial layer 12 facing away from the substrate 11 and the pre-counterweight layer 21 being in contact with the sacrificial layer 12.

[0056] S20, performing a patterning process on the pre-counterweight layer 21 to form a plurality of counterweight portions 1321 arranged in an array, the plurality of counterweight portions 1321 forming a counterweight layer 132, wherein, in the thickness direction of the prefabricated substrate, the counterweight portion 1321 is in contact with the corresponding light-emitting diode chip 1311.

[0057] As Figure 5 and Figure 6 shown, in some alternative embodiments of the second aspect of the present application, the method for preparing a transfer substrate includes:

[0058] S10, forming a pre-counterweight layer 21 on a prefabricated substrate, the prefabricated substrate including a substrate 11 and a sacrificial layer 12 arranged in a stacked manner, the pre-counterweight layer 21 being provided on the side of the sacrificial layer 12 facing away from the substrate 11 and the pre-counterweight layer 21 being in contact with the sacrificial layer 12.

[0059] S11. Transfer the light-emitting diode chip 1311 on the growth substrate to the side of the pre-counterweight layer 21 facing away from the sacrificial layer 12 using the temporary transfer substrate 4. The electrode side of the light-emitting diode chip 1311 faces the pre-counterweight layer 21. The light-emitting diode chip 1311 is temporarily bonded to the pre-counterweight layer 21, and the temporary transfer substrate 4 is peeled off from the light-emitting diode chip 1311 by laser lift-off technology. A plurality of light-emitting diode chips 1311 form a chip layer 131.

[0060] S20. Pattern the pre-counterweight layer 21 to form a plurality of counterweight portions 1321 arranged in an array. The plurality of counterweight portions 1321 form a counterweight layer 132. Among them, in the thickness direction of the prefabricated substrate, the counterweight portion 1321 is in contact with the corresponding light-emitting diode chip 1311.

[0061] As Figures 7 to 8 shown, in some alternative embodiments of the second aspect of the present application, a method for preparing a transfer substrate includes:

[0062] S01. The prefabricated substrate includes a substrate 11 and a sacrificial layer 12 arranged in a stacked manner. Transfer the light-emitting diode chip 1311 on the growth substrate to the sacrificial layer 12 using the temporary transfer substrate 4, and peel off the temporary transfer substrate 4 from the light-emitting diode chip 1311 by laser lift-off technology. A plurality of light-emitting diode chips 1311 form a chip layer 131.

[0063] S02. Form a pre-counterweight layer 21 on the side of the chip layer 131 facing away from the sacrificial layer 12.

[0064] S03. Pattern the pre-counterweight layer 21 to form a plurality of counterweight portions 1321 arranged in an array. The plurality of counterweight portions 1321 form a counterweight layer 132. Among them, in the thickness direction of the prefabricated substrate, the counterweight portion 1321 is in contact with the corresponding light-emitting diode chip 1311.

[0065] As Figure 9 shown, the third aspect of the present application provides a transfer method, including:

[0066] S10'. Provide the transfer substrate in the first aspect of the present application.

[0067] S20'. Use a laser to peel off the sacrificial layer 12 from the chip transfer layer 13, so that the counterweight portion 1321 is transferred to the driving backplane together with the light-emitting diode chip 1311.

[0068] In some alternative embodiments, after the counterweight portion 1321 is transferred to the driving backplane together with the light-emitting diode chip 1311, when the counterweight portion 1321 is located on the side of the light-emitting diode chip 1311 facing away from the driving backplane, after step S20' is executed, the counterweight portion 1321 is removed so as to reduce the overall thickness of the subsequent formed display panel.

[0069] The transfer method according to the third aspect of the present application has a high transfer accuracy, can prevent the light-emitting diode chip 1311 from being displaced or turned over during the transfer process, improve the position accuracy of the transfer of the light-emitting diode chip 1311, thereby improving the product yield and display quality of the display panel.

[0070] According to the embodiments of the present invention as described above, these embodiments do not describe all the details in detail, nor limit the invention to the specific embodiments described. Obviously, according to the above description, many modifications and variations can be made. These embodiments are selected and specifically described in this specification in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and its modified use based on the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A transfer substrate for transferring light-emitting diode chips from a growth substrate to a driving backplane, characterized in that, Comprising: A substrate; A sacrificial layer disposed on the substrate; A chip transfer layer disposed on a side of the sacrificial layer facing away from the substrate, the chip transfer layer including a chip layer and a counterweight layer stacked, Wherein, the chip layer includes a plurality of spaced-apart light-emitting diode chips, the counterweight layer includes a plurality of spaced-apart counterweight portions, the counterweight portions are in one-to-one contact with the light-emitting diode chips, and the counterweight portions are used to be transferred to the driving backplane together with the light-emitting diode chips; The counterweight layer is stacked and in contact with the sacrificial layer, the light-emitting diode chips are disposed on a side of the counterweight portions facing away from the sacrificial layer, and a vertical distance K1 from the center of gravity position of the counterweight portion to the contact surface between the counterweight portion and the light-emitting diode chip is less than or equal to a vertical distance K2 from the center of gravity position of the counterweight portion to the contact surface between the counterweight portion and the sacrificial layer; or, the chip layer is stacked and in contact with the sacrificial layer, and the counterweight portions are disposed on a side of the light-emitting diode chips facing away from the sacrificial layer.

2. The transfer substrate according to claim 1, wherein The chip layer is stacked and in contact with the sacrificial layer, the counterweight portions are disposed on a side of the light-emitting diode chips facing away from the sacrificial layer, the counterweight portions are in the shape of a frustum of a pyramid, the upper bottom surface of the counterweight portion is in contact with the light-emitting diode chips, and the lower bottom surface of the counterweight portion faces away from the light-emitting diode chips.

3. The transfer substrate according to claim 1, wherein, In the thickness direction of the transfer substrate, the thickness of the counterweight portion is less than or equal to the thickness of the corresponding light-emitting diode chip.

4. The transfer substrate according to any one of claims 1 to 3, characterized in that, In the thickness direction of the transfer substrate, the center of gravity of the counterweight portion and the center of gravity of the light-emitting diode chip are on the same vertical line.

5. The transfer substrate according to claim 4, wherein The orthographic projection of the counterweight portion on the substrate covers the orthographic projection of the light-emitting diode chip on the substrate.

6. The transfer substrate according to claim 4, wherein The electrode side of the light-emitting diode chip where the electrode is provided faces the counterweight portion, or the electrode side of the light-emitting diode chip where the electrode is provided faces away from the counterweight portion.

7. A method for preparing a transfer substrate, characterized in that, For preparing the transfer substrate according to any one of claims 1-6, the preparation method includes: Forming a pre-counterweight layer on a prefabricated substrate, the prefabricated substrate including a substrate and a sacrificial layer stacked, the pre-counterweight layer is disposed on a side of the sacrificial layer facing away from the substrate and the pre-counterweight layer is in contact with the sacrificial layer; Performing a patterning process on the pre-counterweight layer to form a plurality of arrayed counterweight portions, and the plurality of counterweight portions form a counterweight layer. Wherein, in the thickness direction of the prefabricated substrate, the counterweight portions are in contact with the corresponding light-emitting diode chips.

8. The preparation method according to claim 7, characterized in that, Before performing the patterning process on the pre-counterweight layer, it further includes: transferring the light-emitting diode chips on the growth substrate to a side of the pre-counterweight layer facing away from the sacrificial layer by using a temporary transfer substrate, the electrode side of the light-emitting diode chips faces the pre-counterweight layer, the light-emitting diode chips are temporarily bonded to the pre-counterweight layer, and the temporary transfer substrate is peeled off from the light-emitting diode chips by using a laser lift-off technique, and the plurality of light-emitting diode chips form a chip layer.

9. A transfer method, characterized in that, Comprising: Providing the transfer substrate according to any one of claims 1 to 6; The sacrificial layer is peeled off from the chip transfer layer by using a laser, so that the counterweight part is transferred to the driving backplane together with the light-emitting diode chip.

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