Epitaxial assembly, light emitting chip transfer method and display screen

Abstract

The application relates to the technical field of semiconductors, and discloses an epitaxial assembly, a light-emitting chip transfer method and a display screen; the epitaxial assembly is used for light-emitting chip transfer and comprises a temporary substrate, a plurality of light-emitting chips and a bottom passivation layer; the plurality of light-emitting chips are arranged at intervals on the temporary substrate, and the light-emitting chips are provided with protruding electrodes on the side, away from the temporary substrate; the bottom passivation layer is formed on the surface of the temporary substrate; the bottom passivation layer is arranged between adjacent light-emitting chips and connected with the side walls of the light-emitting chips, so as to connect all the light-emitting chips into an integrated whole. Through the interaction of the bottom passivation layer, the light-emitting chips cannot be independently detached in the transfer process, but are detached in an integrated manner on the adhesive layer, so that the condition of core particle skewing can be reduced, and the transfer precision is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to an epitaxial component, a method for transferring light-emitting chips, and a display screen. Background Technology

[0002] In the fabrication process of Micro LED chips, transferring the chip from its growth substrate to the driving backplane is a key step. Laser lift-off (LLO) technology, due to its non-contact processing characteristics, has become the mainstream substrate separation method. Specifically, when a laser irradiates a gallium nitride (GaN) chip, the GaN crystal absorbs photon energy and undergoes a thermal decomposition reaction, generating liquid gallium (Ga) and nitrogen gas (N2).

[0003] However, as display resolution continues to improve, the size of Micro LED chips has shrunk to the micrometer level. These chips are extremely lightweight and have low structural rigidity, making them highly sensitive to external mechanical impacts. In mass production processes, the N2 generated during laser peeling is rapidly released from the back of the light-emitting chip. The resulting localized shock waves or jet forces can easily overcome the weak adhesion between the chip and the temporary substrate, causing the chip to rotate in the plane or tilt and overturn vertically. When it falls onto the driving backplate, it becomes difficult to achieve micrometer-level alignment, leading to transfer failures and a sharp drop in mass transfer yield.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide an epitaxial component, a method for transferring light-emitting chips, and a display screen, which aims to solve the problem that in the existing process of transferring light-emitting chips using laser lift-off technology, the chips are prone to misalignment, resulting in transfer failure and a decrease in transfer yield.

[0006] The technical solution of the present invention is as follows: An epitaxial assembly for transferring a light-emitting chip, comprising: Temporary substrate; Several light-emitting chips are arranged at intervals on the temporary substrate, and a protruding electrode is provided on the side of the light-emitting chip facing away from the temporary substrate; A bottom passivation layer is formed on the surface of the temporary substrate; the bottom passivation layer is disposed between adjacent light-emitting chips and connected to the sidewalls of the light-emitting chips to connect all the light-emitting chips into one unit.

[0007] The epitaxial assembly further includes a top passivation layer disposed on the top surface and sidewall of the light-emitting chip, and its edge is connected to the bottom passivation layer.

[0008] The epitaxial assembly, wherein the top passivation layer includes a first portion covering the top surface of the light-emitting chip; The height of the electrode protruding from the light-emitting chip is greater than the thickness of the first part.

[0009] The epitaxial component, wherein the thickness of the first portion is an optical passivation film layer of 500-5000 Å.

[0010] This application also discloses a method for transferring light-emitting chips, comprising: An epitaxial component is provided; the epitaxial component is any of the epitaxial components described above; Peel off the temporary substrate to transfer the bottom passivation layer and the light-emitting chip to the intermediate substrate to obtain a temporary light-emitting component; The temporary light-emitting component is first cleaned in a water bath and then second cleaned in dilute hydrochloric acid. Etch the bottom passivation layer; The intermediate substrate is peeled off, so that all the light-emitting chips are transferred to the transfer substrate.

[0011] The method for transferring a light-emitting chip, wherein the intermediate substrate includes a support layer and a bonding adhesive layer; the step of peeling off the temporary substrate to transfer the bottom passivation layer and the light-emitting chip to the intermediate substrate to obtain a temporary light-emitting component specifically includes: The epitaxial assembly and the intermediate substrate are positioned vertically opposite each other. The epitaxial assembly is irradiated with a laser, causing the bottom passivation layer and the light-emitting chip to detach together onto the intermediate substrate, and the light-emitting chip is then bonded to the substrate using the bonding adhesive layer.

[0012] The method for transferring light-emitting chips, wherein the step of peeling off the intermediate substrate to transfer all the light-emitting chips to the transfer substrate specifically includes: The temporary light-emitting component and the transfer substrate are arranged vertically opposite to each other. The light-emitting chip is detached from the intermediate substrate by the laser penetrating the support layer and dissociating the bonding adhesive layer.

[0013] In the light-emitting chip transfer method described above, the temperature of the water bath is 60°C; or the concentration of the dilute hydrochloric acid is 5%.

[0014] The light-emitting chip transfer method, wherein the step of etching the bottom passivation layer specifically includes: The bottom passivation layer is removed by plasma etching, and the surface of the light-emitting chip is roughened. Rinse the light-emitting chip with clean water to remove debris generated during the etching of the bottom passivation layer.

[0015] This application also discloses a display screen, which includes a driving backplane and a plurality of light-emitting chips arrayed on the driving backplane, wherein the light-emitting chips are transferred to the driving backplane by any of the light-emitting chip transfer methods described above.

[0016] Compared with the prior art, the embodiments of the present invention have the following advantages: The epitaxial component disclosed in this invention connects several light-emitting chips into one unit through a bottom passivation layer, thereby overcoming the impact force generated by the gas when peeling off the temporary substrate, reducing problems such as the offset and flipping of the light-emitting chips, and enabling the entire surface of light-emitting chips to be completely and accurately detached onto the substrate, improving the transfer accuracy to the photolithography level, meeting processing requirements, and improving product yield. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a photograph of the gallium nitride light-emitting chip after it has been transferred using laser lift-off technology in this invention, as observed under a microscope. Figure 2 This is a schematic diagram illustrating the transfer of gallium nitride light-emitting chips using laser lift-off technology in this invention; Figure 3 This is a schematic diagram of the structure of the epitaxial component in this invention; Figure 4 This is a schematic diagram of the temporary substrate removal process in this invention; Figure 5 This is a schematic diagram of the temporary substrate structure in this invention; Figure 6 This is a schematic diagram of etching the bottom passivation layer in this invention; Figure 7 This is a schematic diagram of the process of peeling off the intermediate substrate in this invention; Figure 8 This is a flowchart of the light-emitting chip transfer method in this invention.

[0019] Among them, 10 is an epitaxial component; 11 is a temporary substrate; 12 is a light-emitting chip; 121 is an electrode; 13 is a bottom passivation layer; 14 is a top passivation layer; 20 is a temporary light-emitting component; 21 is an intermediate substrate; 211 is a support layer; 212 is a bonding adhesive layer; and 30 is a transfer substrate. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Due to manufacturing techniques and / or tolerances, variations in the shapes shown in the accompanying drawings may occur. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings, but include changes in shape that may occur during manufacturing. The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all contents, operations, or steps, nor do they necessarily need to be performed in the order described. For example, some operations or steps may be broken down, combined, or partially merged, so the actual order of execution may change depending on the specific circumstances.

[0022] As used herein, the term “and / or” includes any one of the relevant items listed and any combination of any two or more items.

[0023] Although terms such as “first,” “second,” and “third” may be used herein to describe individual components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts are not limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teachings of the examples described herein, the first component, assembly, region, layer, or part referred to as the second component, assembly, region, layer, or part may also be referred to as the second component, assembly, region, layer, or part.

[0024] For ease of description, spatial relational terms such as “above,” “upper,” “below,” and “lower” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. Such spatial relational terms are intended to encompass not only the orientation depicted in the drawings but also different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as being “above” or “upper” relative to another element will subsequently be “below” or “lower” relative to that other element. Therefore, the term “above” includes both “above” and “below” orientations depending on the spatial orientation of the device. The device may also be positioned in other ways, and the spatial relational terms used herein will be interpreted accordingly.

[0025] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0026] Currently, the structure of light-emitting chips is mainly transferred using laser lift-off, such as... Figure 1 and Figure 2 As shown, during the laser stripping process, when the laser irradiates the gallium nitride light-emitting chip, the gallium nitride crystal decomposes to produce nitrogen gas. The amount of nitrogen gas produced is related to the duration and energy of the laser action. Since the light-emitting chip is small in size and light in weight, when nitrogen gas is released from the back of the light-emitting chip, it can easily cause a large impact on the chip, resulting in chip misalignment. This makes it difficult for the light-emitting chip to be aligned with the backplate during the transfer process, causing transfer failure.

[0027] like Figure 3 As shown, in one embodiment of this invention application, an epitaxial assembly 10 is disclosed for transferring light-emitting chips 12. It includes a temporary substrate 11, a plurality of light-emitting chips 12, and a bottom passivation layer 13. The plurality of light-emitting chips 12 are arranged at intervals on the temporary substrate 11, and a protruding electrode is provided on the side of the light-emitting chip facing away from the temporary substrate. The bottom passivation layer 13 is formed on the surface of the temporary substrate 11. The bottom passivation layer 13 is disposed between adjacent light-emitting chips 12 and connected to the sidewall of the light-emitting chip 12 to connect all the light-emitting chips 12 into one unit.

[0028] In this embodiment, a sapphire (Al2O3) substrate can be used as the temporary substrate 11, and a plurality of light-emitting chips 12 are arrayed on the temporary substrate 11. The light-emitting chip 12 disclosed in this embodiment can be any one of a micro light-emitting diode (Micro LED) chip or a mini light-emitting diode (Mini LED) chip. It should be noted that this embodiment is only an example of the types of temporary substrate 11 and light-emitting chip 12, but the scope of protection of this invention is not limited thereto. Other types of temporary substrate 11 and light-emitting chip 12, as long as they can achieve the technical effects disclosed in this application, can be considered as equivalent substitutions for the inventive concept and should also be within the scope of protection of this application.

[0029] Specifically, a bottom passivation layer 13 is deposited on the surface of the temporary substrate 11. The sidewalls of the bottom passivation layer 13 are in contact with and connected to the sidewalls of the light-emitting chips 12. The bottom passivation layer 13 connects several light-emitting chips 12 into one unit, achieving the effect of physical interconnection. In other words, the bottom passivation layer 13 provides support for the sidewalls of each light-emitting chip 12, thus preventing skewing.

[0030] When the temporary substrate 11 is peeled off, the light-emitting chip 12 on the whole side and the bottom passivation layer 13 are connected to each other and support each other, which can overcome the impact force generated when nitrogen is released. This helps to reduce the offset and flipping of the light-emitting chip 12, so that the light-emitting chip 12 on the whole side can be completely and accurately removed, improving the transfer accuracy to the photolithography level. Ultimately, this can meet the processing requirements and improve the product yield.

[0031] For example Figure 3 As shown, in another embodiment of this application, the epitaxial component 10 further includes a top passivation layer 14, which is disposed on the top surface and sidewalls of the light-emitting chip 12, and its edge is connected to the bottom passivation layer 13. The top passivation layer 14 disclosed in this embodiment can protect the light-emitting chip 12 through physical and chemical isolation.

[0032] Specifically, the top passivation layer 14 and the bottom passivation layer 13 are deposited in one step using plasma-enhanced chemical vapor deposition (PECVD). Compared to the traditional fabrication process of the light-emitting chip 12, this embodiment combines the fabrication process of the light-emitting chip 12 with the transfer process of the light-emitting chip 12. During the formation of the light-emitting chip 12 on the temporary substrate 11, the top passivation layer 14 and the bottom passivation layer 13 are deposited simultaneously, resulting in higher production efficiency of the epitaxial component 10, as the bottom passivation layer 13 does not need to be deposited separately.

[0033] Specifically, the top passivation layer 14 and the bottom passivation layer 13 disclosed in this embodiment can be made of silicon dioxide, silicon nitride or aluminum oxide, and are not limited thereto.

[0034] For example Figure 3 As shown, in another embodiment of this application, the top passivation layer 14 includes a first portion covering the top surface of the light-emitting chip 12; the height of the electrode 121 protruding from the light-emitting chip 12 is greater than the thickness of the first portion.

[0035] In this embodiment, the light-emitting chip 12 is flip-chip mounted on the temporary substrate 11. Therefore, an electrode 121 is provided on the side of the light-emitting chip 12 facing away from the temporary substrate 11. To bond the electrode 121 to the driving backplane, the electrode 121 needs to protrude to ensure a high bonding success rate. Therefore, in this embodiment, the thickness of the first portion is set to be less than or equal to the height of the protruding portion of the electrode 121 to facilitate bonding between the electrode 121 and the driving backplane.

[0036] Specifically, in this embodiment, two adjacent light-emitting chips 12 are connected only through a bottom passivation layer 13, but the top passivation layers 14 of adjacent light-emitting chips 12 are not connected. This is because if the top passivation layers 14 were connected, it would result in an excessively thick passivation layer, making the subsequent removal process complex and difficult to operate.

[0037] Specifically, as another embodiment of this application, the thickness of the first part of the optical passivation layer is disclosed to be 500-5000 Å. For example, 4600 Å, 4800 Å, or 5000 Å. The first part disclosed in this embodiment is used to protect the light-emitting chip 12. The thickness should not be too large or too thin. If it is too thin, it is easy to cause poor sidewall coverage of the light-emitting chip 12, resulting in leakage of the light-emitting chip 12.

[0038] It should be noted that this embodiment only illustrates the thickness of the first part, but the scope of protection of the present invention is not limited thereto. As long as the first part within a suitable thickness range can achieve the technical effect disclosed in this application, it can be regarded as an equivalent replacement of the concept of the present invention and should also be within the scope of protection of this application.

[0039] like Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, as another embodiment of this application, a method for transferring a light-emitting chip is also disclosed, comprising: Step S10: Provide an extension component 10.

[0040] The epitaxial component 10 disclosed in this embodiment is any of the epitaxial components 10 described above. A plurality of light-emitting chips 12 to be transferred are formed on the epitaxial component 10, and a bottom passivation layer 13 is formed in the gap between adjacent light-emitting chips 12. Therefore, the passivation layer on the surface of the entire epitaxial component 10 and all the light-emitting chips 12 are integrated into one, and the overall structure is stable.

[0041] Step S20: Peel off the temporary substrate 11, so that the bottom passivation layer 13 and the light-emitting chip 12 are transferred to the intermediate substrate 21 to obtain the temporary light-emitting component 20.

[0042] like Figure 4 As shown, in this embodiment, the temporary substrate 11 can be removed by laser stripping. Liquid gallium ions and nitrogen gas are generated during the stripping process. Although the nitrogen gas has a certain impact force, the light-emitting chip 12 and the passivation layer are an integral structure, which can overcome the local impact force and thus accurately transfer them to the intermediate substrate 21, improving the transfer accuracy.

[0043] In another embodiment of this invention, the intermediate substrate 21 includes a support layer 211 and a bonding adhesive layer 212; step S20 specifically includes: Step S21: The epitaxial assembly 10 and the intermediate substrate 21 are arranged vertically opposite each other; Step S22: Irradiate the epitaxial component 10 with a laser to cause the bottom passivation layer 13 and the light-emitting chip 12 to fall off together onto the intermediate substrate 21, and then attach the light-emitting chip 12 through the bonding adhesive layer 212.

[0044] The support layer 211 disclosed in this embodiment can be a sapphire substrate to support the bonding adhesive layer 212. The bonding adhesive layer 212 is adhesive and can adhere to the light-emitting chip 12. When the gallium nitride crystal is irradiated with a 248 nm laser, the gallium nitride crystal decomposes. Therefore, with the help of gravity, the light-emitting chip 12 and the bottom passivation layer 13 automatically fall onto the intermediate substrate 21. Since the entire structure falls and is transferred together, the light-emitting chips 12 will not fall off one by one. Therefore, problems such as displacement, skewness, and flipping can be greatly reduced, and the success rate of transfer can be improved.

[0045] Step S30: Perform a first cleaning of the temporary light-emitting component 20 in a water bath, and a second cleaning of the temporary light-emitting component 20 in dilute hydrochloric acid.

[0046] In this embodiment, a water bath is used to clean the liquid gallium metal ions generated during the first transfer process. Preferably, the water bath temperature is 60°C. After water bath cleaning, a second cleaning is performed with dilute hydrochloric acid to further improve the removal rate and reduce residue. Preferably, the concentration of dilute hydrochloric acid is 5%.

[0047] Moreover, in this step, most of the gallium ions (about 90%) are removed first by water bath. When cleaning with dilute hydrochloric acid in the subsequent step, the concentration of gallium ions in the dilute hydrochloric acid can be reduced, or in other words, the concentration of gallium chloride (GaCl3) can be reduced, thereby avoiding the problem of electrochemical corrosion and preventing Au migration.

[0048] Step S40: Etch the bottom passivation layer 13.

[0049] like Figure 6 As shown, by removing the bottom passivation layer 13, the adjacent light-emitting chips 12 are unbound to facilitate subsequent individual picking.

[0050] In another embodiment of this example, step S40 specifically includes: Step S41: Remove the bottom passivation layer 13 using a plasma etching process and roughen the surface of the light-emitting chip 12; Step S42: Rinse the light-emitting chip 12 with clean water to remove debris generated during the etching of the bottom passivation layer 13.

[0051] In this embodiment, the bottom passivation layer 13 can be removed by inductively coupled plasma etching (ICP) to remove the passivation layer on the back of the light-emitting chip 12, thus separating the light-emitting chips 12 for independent handling. Furthermore, debris is rinsed off with water to keep the surface of the light-emitting chip 12 clean, preparing it for the next transfer step.

[0052] In addition, during this step, the etching process simultaneously roughens the surface of the light-emitting chip 12, thereby reducing total internal reflection and achieving the effect of further increasing the brightness of the light-emitting chip, which is beneficial to improving the brightness and enhancing the light-emitting effect of the light-emitting chip 12.

[0053] Step S50: Peel off the intermediate substrate 21 so that all the light-emitting chips 12 are transferred to the transfer substrate 30.

[0054] like Figure 7 As shown, by irradiating the intermediate substrate 21 with a laser, the bonding adhesive layer 212 can be dissociated, thereby separating the light-emitting chip 12 from the intermediate substrate 21 and transferring it to the transfer substrate 30 to obtain the final product.

[0055] In another embodiment of this example, step S50 specifically includes: Step S51: Position the temporary light-emitting component 20 and the transfer substrate 30 vertically opposite each other; Step S52: The light-emitting chip 12 is detached from the intermediate substrate 30 by laser penetration of the support layer 211 and separation of the bonding adhesive layer 212.

[0056] Since the bonding adhesive layer 212 is made of adhesive material, the reaction is milder and the amount of gas produced is less when irradiated by laser, so it will not adversely affect the transfer of the light-emitting chip 12. In other words, the light-emitting chip 12 falls off the bonding adhesive layer 212 and falls onto the transfer substrate 30 under the action of gravity. The drop position is fixed, the transfer accuracy is high, and it is beneficial to improve the product yield.

[0057] Specifically, the intermediate substrate 30 disclosed in this embodiment can also use a sapphire substrate as a support structure, and an adhesive layer is formed on the sapphire substrate to adhere the light-emitting chip 12. In addition, the adhesive layer on the intermediate substrate 30 is made of a different material than the bonding adhesive layer 212 on the intermediate substrate 21, and the dissociation method is different, which can be selected according to the actual processing conditions.

[0058] Furthermore, after the light-emitting chip 12 is transferred to the transfer substrate 30 using the light-emitting chip transfer method disclosed in this embodiment, it can be sold separately. Alternatively, the light-emitting chip 12 on the transfer substrate 30 can be transferred to the driver backplane and packaged according to product needs, and sold as a display screen as a sales unit.

[0059] Specifically, as another embodiment of this application, a display screen is also disclosed, which includes a driving backplane and a plurality of light-emitting chips 12 arrayed on the driving backplane. The light-emitting chips 12 are transferred to the driving backplane by any of the light-emitting chip transfer methods described above.

[0060] In summary, this application discloses an epitaxial assembly 10, a method for transferring light-emitting chips, and a display screen. The epitaxial assembly 10 is used for transferring light-emitting chips 12 and includes a temporary substrate 11, a plurality of light-emitting chips 12, and a bottom passivation layer 13. The plurality of light-emitting chips 12 are arranged at intervals on the temporary substrate 11. The bottom passivation layer 13 is formed on the surface of the temporary substrate 11. The bottom passivation layer 13 is disposed between adjacent light-emitting chips 12 and connected to the sidewalls of the light-emitting chips 12 to connect all the light-emitting chips 12 into one unit. By connecting the plurality of light-emitting chips 12 into one unit through the bottom passivation layer 13, the impact force generated by the gas is overcome during the transfer of the light-emitting chips 12, reducing problems such as offset and flipping of the light-emitting chips 12. This allows the entire surface of the light-emitting chips 12 to be completely and accurately detached onto the driving backplane, improving the transfer accuracy to the photolithography level, meeting processing requirements, and improving product yield.

[0061] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0062] It should be noted that the present invention is described using epitaxial components, light-emitting chip transfer methods, and displays as examples to illustrate the specific structure and working principle of the present invention. However, the application of the present invention is not limited to epitaxial components, light-emitting chip transfer methods, and displays, and can also be applied to the production and use of other similar workpieces.

[0063] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An epitaxial assembly for transferring light-emitting chips, characterized in that, include: Temporary substrate; Several light-emitting chips are arranged at intervals on the temporary substrate, and a protruding electrode is provided on the side of the light-emitting chip facing away from the temporary substrate; A bottom passivation layer is formed on the surface of the temporary substrate; the bottom passivation layer is disposed between adjacent light-emitting chips and connected to the sidewalls of the light-emitting chips to connect all the light-emitting chips into one unit.

2. The epitaxial component according to claim 1, characterized in that, The epitaxial component also includes a top passivation layer, which is disposed on the top surface and sidewall of the light-emitting chip, and its edge is connected to the bottom passivation layer.

3. The epitaxial component according to claim 2, characterized in that, The top passivation layer includes a first portion covering the top surface of the light-emitting chip; The height of the electrode protruding from the light-emitting chip is greater than the thickness of the first part.

4. The epitaxial component according to claim 3, characterized in that, The thickness of the first part is 500-5000 Å, which is the thickness of the optical passivation layer.

5. A method for transferring a light-emitting chip, characterized in that, include: Provide an epitaxial component; The epitaxial component is the epitaxial component as described in any one of claims 1 to 4; Peel off the temporary substrate to transfer the bottom passivation layer and the light-emitting chip to the intermediate substrate to obtain a temporary light-emitting component; The temporary light-emitting component is first cleaned in a water bath and then second cleaned in dilute hydrochloric acid. Etch the bottom passivation layer; The intermediate substrate is peeled off, so that all the light-emitting chips are transferred to the transfer substrate.

6. The light-emitting chip transfer method according to claim 5, characterized in that, The intermediate substrate includes a support layer and a bonding adhesive layer; the step of peeling off the temporary substrate to transfer the bottom passivation layer and the light-emitting chip to the intermediate substrate to obtain the temporary light-emitting component specifically includes: The epitaxial assembly and the intermediate substrate are positioned vertically opposite each other. The epitaxial assembly is irradiated with a laser, causing the bottom passivation layer and the light-emitting chip to detach together onto the intermediate substrate, and the light-emitting chip is then bonded to the substrate using the bonding adhesive layer.

7. The light-emitting chip transfer method according to claim 6, characterized in that, The step of peeling off the intermediate substrate and transferring all the light-emitting chips to the transfer substrate specifically includes: The temporary light-emitting component and the transfer substrate are arranged vertically opposite to each other. The light-emitting chip is detached from the intermediate substrate by the laser penetrating the support layer and dissociating the bonding adhesive layer.

8. The light-emitting chip transfer method according to claim 5, characterized in that, The water bath temperature is 60℃; or the concentration of dilute hydrochloric acid is 5%.

9. The light-emitting chip transfer method according to claim 5, characterized in that, The step of etching the bottom passivation layer specifically includes: The bottom passivation layer is removed by plasma etching, and the surface of the light-emitting chip is roughened. Rinse the light-emitting chip with clean water to remove debris generated during the etching of the bottom passivation layer.

10. A display screen, characterized in that, The device includes a driving backplane and a plurality of light-emitting chips arranged in an array on the driving backplane, wherein the light-emitting chips are transferred to the driving backplane by the light-emitting chip transfer method as described in any one of claims 5 to 9.

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