Chip transfer method and display panel

Abstract

The present application relates to a chip transfer method and a display panel. The chip transfer method comprises: providing a temporary substrate, a surface of the temporary substrate being formed with a chip; providing a back plate, a surface of the back plate being formed with a sacrificial layer; facing the surface of the temporary substrate formed with the chip towards the sacrificial layer; separating the chip to be transferred from the temporary substrate, so that the chip to be transferred falls vertically to the surface of the sacrificial layer away from the back plate; removing the sacrificial layer, so that the chip is bonded with the back plate. The chip transfer method can fix the chip by making the chip fall on the surface of the sacrificial layer first, limit the chip to a fixed position, and avoid the deflection that may occur in the process of directly falling into the back plate after the chip to be transferred is separated from the temporary substrate in the traditional chip transfer technology, thereby improving the consistency of the angle of the chip during the chip transfer.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more particularly to a chip transfer method and a display panel. Background Technology

[0002] As light-emitting diode (LED) displays gradually move towards ultra-high-definition display, micro LEDs, with their extremely superior ultra-high-definition display effects, are gradually becoming a major trend in the future LED display industry.

[0003] Currently, the size of Micro LED chips has been developed to below 100 micrometers. In order to meet the mass production needs brought about by the commercialization of Micro LED, mass transfer technology has emerged. The purpose is to transfer chips onto the target substrate or circuit, requiring the transfer of millions of chips onto the required backplane.

[0004] However, in traditional chip transfer technology, because a certain distance must be maintained between the growth substrate or transient substrate and the circuit backplane, the chip is prone to tilting and flipping during the transfer process to the circuit backplane; therefore, how to avoid chip tilting during the transfer process is an urgent problem to be solved. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this application is to provide a chip transfer method and a display panel, which aims to avoid chip skew during the transfer process.

[0006] A chip transfer method includes the following steps:

[0007] A transient substrate is provided, and a chip is formed on the surface of the transient substrate;

[0008] A backplate is provided, and a sacrificial layer is formed on the surface of the backplate;

[0009] The surface of the transient substrate on which the chip is formed faces the sacrificial layer;

[0010] The chip to be transferred is separated from the transient substrate so that the chip to be transferred is dropped vertically onto the surface of the sacrificial layer away from the backplane;

[0011] Remove the sacrificial layer to bond the chip to the backplane.

[0012] In the chip transfer method described above, a sacrificial layer is pre-formed on the surface of the backplane before the chip to be transferred is transferred. This allows the chip to fall onto the surface of the sacrificial layer after it is separated from the transient substrate. The sacrificial layer can fix the chip and confine it to a fixed position. By allowing the chip to fall onto the surface of the sacrificial layer first, the skewness that may occur when the chip to be transferred falls directly into the backplane after being separated from the transient substrate in traditional chip transfer technology can be avoided, thus improving the consistency of the chip angle during chip transfer.

[0013] Furthermore, the chip transfer method described above forms a sacrificial layer on the surface of the backplane. Since the sacrificial layer has a high absorption rate for laser, less laser energy is transmitted to the chip through the sacrificial layer. Therefore, the chip transfer method described above can also avoid electrical damage to the chip caused by the laser, thus achieving non-destructive transfer of the chip.

[0014] Optionally, the sacrificial layer includes a photodegradable adhesive layer or a thermally degradable adhesive layer; the transient substrate includes a gallium nitride substrate.

[0015] The chip transfer method described above pre-forms a photodegradable adhesive layer or a thermal degradable adhesive layer on the surface of the backplane before transferring the chip to be transferred. Both the photodegradable adhesive layer and the thermal degradable adhesive layer have a certain degree of adhesion, so they can effectively fix the chip and confine the chip to a fixed position.

[0016] Furthermore, the aforementioned chip transfer method forms a photodegradable adhesive layer on the surface of the backplane. Since the photodegradable adhesive layer has a very high absorption rate for laser light, very little laser energy is transmitted through the photodegradable adhesive layer to the chip. Therefore, the aforementioned chip transfer method can further avoid electrical damage to the chip caused by the laser, thus achieving non-destructive chip transfer.

[0017] The aforementioned chip transfer method provides a gallium nitride substrate. During the separation of the chip to be transferred from the gallium nitride substrate, gallium nitride can be decomposed to generate nitrogen gas. The impact force of the gas can cause the chip to fall vertically onto the photoresist layer or thermal resist layer, further improving the consistency of the chip angle during chip transfer. Moreover, since gallium nitride can switch higher voltages and larger currents faster than other materials, achieving higher switching speeds and reducing corresponding losses, the aforementioned chip transfer method, by providing a gallium nitride substrate, can effectively solve the heat dissipation problem during light emission and can also increase the brightness per unit area by several times.

[0018] Optionally, the thickness of the sacrificial layer is greater than the thickness of the chip.

[0019] The chip transfer method described above can be repeated multiple times because the thickness of the sacrificial layer is greater than the thickness of the chip, thereby achieving selective transfer or re-transfer of the chip. Furthermore, this method can be applied to chip repair processes.

[0020] Optionally, separating the chip to be transferred from the transient substrate includes the following steps:

[0021] The transient substrate is irradiated with a laser at a surface away from the chip to separate the chip to be transferred from the transient substrate.

[0022] Optionally, the backplate has pads on its surface, and the sacrificial layer covers the surface of the backplate on which the pads are formed and the pads.

[0023] After the surface of the transient substrate on which the chip is formed faces the sacrificial layer, the chip is aligned and distributed with the pads.

[0024] Remove the sacrificial layer located between the chip and the backplane so that after the chip is bonded to the backplane, the chip contacts and bonds to the pads.

[0025] Optionally, removing the sacrificial layer includes the following steps:

[0026] First, remove the portion of the sacrificial layer located between adjacent chips, or form a groove within the sacrificial layer, the groove surrounding the chip;

[0027] The sacrificial layer located between the chip and the backplane is then removed to bond the chip to the backplane.

[0028] The chip transfer method described above first removes the portion of the sacrificial layer located between adjacent chips, while retaining the portion of the sacrificial layer located below the chip. Since there is no sacrificial layer residue between adjacent chips, it can avoid the chip skew problem caused by the thermal effect generated when removing the sacrificial layer located between the chip and the backplane, which would cause the sacrificial layer between adjacent chips to melt and accumulate. This ensures the consistency of the chip angle during chip transfer.

[0029] The chip transfer method described above also avoids chip misalignment by forming a groove around the chip within the sacrificial layer, thus preventing the thermal effect generated during the subsequent removal of the sacrificial layer located between the chip and the backplane from causing the sacrificial layer between adjacent chips to melt and accumulate, thereby ensuring the consistency of chip angle during chip transfer.

[0030] Optionally, removing the sacrificial layer located between the chip and the backplane includes the following steps:

[0031] The backplane surface away from the chip is irradiated with a laser to remove the sacrificial layer between the chip and the backplane, thereby bringing the chip into contact with the backplane.

[0032] Optionally, the step of using a laser to irradiate the surface of the backplane away from the chip to remove the sacrificial layer between the chip and the backplane includes the following steps:

[0033] The backplane is periodically irradiated with a laser to remove the sacrificial layer of a preset thickness, until the sacrificial layer between the chip and the backplane is completely removed, so that the chip slowly descends to the surface of the backplane.

[0034] The chip transfer method described above removes a sacrificial layer of a preset thickness in successive steps, allowing the chip to descend slowly and evenly to the surface of the backplane. This avoids problems such as skewness, flipping, or residual adhesive caused by rapid chip descent, and further ensures the consistency of chip angle during chip transfer.

[0035] Optionally, after removing the sacrificial layer, the chip bonded to the backplane is the first chip; after bonding the first chip to the backplane, the following steps are further included:

[0036] The second chip is transferred using the same transfer steps as the first chip, so that the second chip is bonded to the backplane; the first chip and the second chip are arranged periodically and alternately on the surface of the backplane.

[0037] The chip transfer method described above can transfer other chips again by repeating the chip transfer method steps provided in any of the aforementioned embodiments to transfer the second chip in the same transfer steps as the first chip. It can also transfer new chips on the backplane surface where chips have already been bonded, thus realizing multiple chip transfers.

[0038] Based on the same inventive concept, this application also provides a display panel, including a back panel and a plurality of chips located on the surface of the back panel; wherein

[0039] Multiple chips are transferred to the surface of the backplane using a chip transfer method as provided in any of the foregoing embodiments.

[0040] The aforementioned display panel includes multiple chips that have been transferred to the backplane surface using the chip transfer method provided in the aforementioned embodiments. Therefore, the display panel can also achieve the technical effects that the aforementioned chip transfer method can achieve, and will not be described in detail here. Attached Figure Description

[0041] Figure 1 Flowcharts of chip transfer methods provided for some embodiments of this application;

[0042] Figure 2 A cross-sectional schematic diagram of the structure obtained in steps S101, S102 and S103 in a chip transfer method provided in some embodiments of this application.

[0043] Figure 3A cross-sectional schematic diagram of the structure obtained in step S104 in a chip transfer method provided in some embodiments of this application;

[0044] Figure 4 A flowchart of step S105 in a chip transfer method provided in some embodiments of this application;

[0045] Figure 5 A cross-sectional schematic diagram of the structure obtained in step S401 of the chip transfer method provided in some embodiments of this application; wherein, Figure 5 Figure (a) is a schematic cross-sectional view of the structure obtained by removing the portion of the sacrificial layer located between adjacent chips in some embodiments of this application; Figure 5 Figure (b) is a schematic cross-sectional view of the structure obtained by forming a groove in the sacrificial layer in some embodiments of this application;

[0046] Figure 6 A cross-sectional schematic diagram of the structure obtained in step S402 of the chip transfer method provided in some embodiments of this application; wherein, Figure 6 Figure (a) is a cross-sectional view of the structure obtained in step S402 in some embodiments of this application where the portion of the sacrificial layer is removed between adjacent chips; Figure 6 Figure (b) is a cross-sectional schematic diagram of the structure obtained in step S402 in some embodiments of this application in which a groove is formed in the sacrificial layer;

[0047] Figure 7 A cross-sectional schematic diagram of a structure obtained by periodically irradiating a backplane away from the chip surface using a laser in a chip transfer method provided in some embodiments of this application; wherein, Figure 7 Figure (a) is a schematic cross-sectional view of the structure obtained by periodically irradiating the backplane away from the chip surface with a laser in some embodiments of this application where the portion of the sacrificial layer located between adjacent chips is removed. Figure 7 Figure (b) is a schematic cross-sectional view of the structure obtained by periodically irradiating the backplate away from the chip surface with a laser in some embodiments of the present application in which a groove is formed in the sacrificial layer.

[0048] Figure 8 A schematic diagram of the cross-sectional structure of the chip-backplane bonding in a chip transfer method provided in some embodiments of this application;

[0049] Figure 9 Figures (a) to (e) are schematic cross-sectional views of the steps in which the second chip is bonded to the backplane in the chip transfer method provided in some embodiments of this application.

[0050] Explanation of reference numerals in the attached figures:

[0051] 101-Transient substrate; 102-Chip; 201-Backplane; 202-Sacrificial layer; 203-Pad; 204-Groove; 301-First chip; 302-Second chip. Detailed Implementation

[0052] 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.

[0053] 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.

[0054] As light-emitting diode (LED) displays gradually move towards ultra-high-definition display, micro LEDs, with their extremely superior ultra-high-definition display effects, are gradually becoming a major trend in the future LED display industry.

[0055] Currently, the size of Micro LED chips has been developed to below 100 micrometers. In order to meet the mass production needs brought about by the commercialization of Micro LED, mass transfer technology has emerged. The purpose is to transfer chips onto the target substrate or circuit, requiring the transfer of millions of chips onto the required backplane.

[0056] However, in traditional chip transfer technology, because a certain distance must be maintained between the growth substrate or transient substrate and the circuit backplane, the chip is prone to tilting and flipping during the transfer process to the circuit backplane; therefore, how to avoid chip tilting during the transfer process is an urgent problem to be solved.

[0057] 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.

[0058] Please see Figure 1 According to some embodiments, this application provides a chip transfer method, which may include the following steps:

[0059] Includes the following steps:

[0060] S101: Provide a transient substrate; specifically, a chip is formed on the surface of the transient substrate;

[0061] S102: Provide a backplate, wherein a sacrificial layer is formed on the surface of the backplate;

[0062] S103: The surface of the transient substrate with the chip formed thereon is facing the sacrificial layer;

[0063] S104: Separate the chip to be transferred from the transient substrate so that the chip to be transferred falls vertically onto the surface of the sacrificial layer away from the backplane;

[0064] S105: Remove the sacrificial layer to allow the chip to bond to the backplane.

[0065] In the chip transfer method described above, a sacrificial layer is pre-formed on the surface of the backplane before the chip to be transferred is transferred. This allows the chip to fall onto the surface of the sacrificial layer after it is separated from the transient substrate. The sacrificial layer can fix the chip and confine it to a fixed position. By allowing the chip to fall onto the surface of the sacrificial layer first, the skewness that may occur when the chip to be transferred falls directly into the backplane after being separated from the transient substrate in traditional chip transfer technology can be avoided, thus improving the consistency of the chip angle during chip transfer.

[0066] Furthermore, the chip transfer method described above forms a sacrificial layer on the surface of the backplane. Since the sacrificial layer has a high absorption rate for laser, less laser energy is transmitted to the chip through the sacrificial layer. Therefore, the chip transfer method described above can also avoid electrical damage to the chip caused by the laser, thus achieving non-destructive transfer of the chip.

[0067] The following is combined Figures 2 to 9 This application provides a detailed description of some implementation methods for chip transfer.

[0068] In step S101, please refer to Figure 2 A transient substrate 101 is provided; specifically, a chip 102 is formed on the surface of the transient substrate 101.

[0069] Optionally, the material of the transient substrate 101 may include, but is not limited to, silicon (Si), silicon carbide (SiC), sapphire, quartz, gallium nitride (GaN), or gallium arsenide (GaAs), etc. That is, the transient substrate 101 may include, but is not limited to, silicon substrate, silicon carbide substrate, sapphire substrate, quartz substrate, gallium nitride substrate, or gallium arsenide substrate, etc.; this application does not limit the specific material of the transient substrate 101.

[0070] In some embodiments, the transient substrate 101 includes a gallium nitride substrate.

[0071] The chip transfer method described above provides a gallium nitride substrate. During the process of separating the chip 102 to be transferred from the gallium nitride substrate, gallium nitride can be decomposed to generate nitrogen gas. The impact force of the gas can cause the chip 102 to fall vertically onto the sacrificial layer 202, further improving the consistency of the angle of the chip 102 during transfer. Moreover, since gallium nitride can switch higher voltages and larger currents faster than other materials, it can achieve higher switching speeds and reduce corresponding losses. Therefore, the chip transfer method described above, by providing a gallium nitride substrate, can effectively solve the heat dissipation problem during light emission and can also increase the brightness per unit area by several times.

[0072] Optionally, chip 102 may be, but is not limited to, Micro LED chip, Mini LED chip, photodetector diode, MOS device, or micro-electro-mechanical system (MEMS) device, etc. This application does not limit the type of chip 102.

[0073] In step S102, please continue reading. Figure 2 A backplate 201 is provided, and a sacrificial layer 202 is formed on the surface of the backplate 201.

[0074] Optionally, the backplane 201 may include, but is not limited to, a driving backplane. This application does not limit the specific form of the backplane 201. Optionally, the backplane 201 may include, but is not limited to, a printed circuit board (PCB), a glass substrate, a silicon substrate, or a silicon carbide substrate, etc. This application does not limit the specific material of the backplane 201.

[0075] Optionally, the material of the sacrificial layer 202 may include, but is not limited to, photodegradable adhesive or pyrodegradable adhesive, that is, the sacrificial layer 202 may include, but is not limited to, a photodegradable adhesive layer or a pyrodegradable adhesive layer.

[0076] In some embodiments, the sacrificial layer 202 includes a photopolymer layer.

[0077] In the chip transfer method described above, a photoresist layer is formed on the surface of the backplate 201 before transferring the chip 102 to be transferred. The photoresist layer has a certain degree of adhesion, so it can effectively fix the chip 102 and restrict the chip 102 to a fixed position.

[0078] Furthermore, the above-mentioned chip transfer method forms a photodegradable adhesive layer on the surface of the backplane 201. Since the photodegradable adhesive layer has a very high absorption rate for laser, very little laser energy is transmitted through the photodegradable adhesive layer to the chip 102. Therefore, the above-mentioned chip transfer method can further avoid the laser from causing electrical damage to the chip 102, and achieve the non-destructive transfer of the chip 102.

[0079] In some implementations, the thickness of the sacrificial layer 202 may be greater than the thickness of the chip 102.

[0080] The above chip transfer method allows for repeated processing because the thickness of the sacrificial layer 202 is greater than that of the chip 102. This enables selective transfer or re-transfer of the chip 102 and also allows the method to be applied to the repair process of the chip 102.

[0081] In step S103, please continue reading. Figure 2 The surface of the transient substrate 101 on which the chip 102 is formed is oriented toward the sacrificial layer 202.

[0082] In step S104, please refer to Figure 3 The chip 102 to be transferred is separated from the transient substrate 101 so that the chip 102 to be transferred falls vertically onto the surface of the sacrificial layer 202 away from the backplate 201.

[0083] For step S104, in some embodiments, the transient substrate 101 may be separated from the transient substrate 101 by means of laser irradiation away from the surface of the chip 102. This application does not limit the specific method of separating the chip 102 to be transferred from the transient substrate 101.

[0084] In step S105, please refer to Figures 4 to 8 Remove the sacrificial layer 202 to bond the chip 102 to the backplane 201.

[0085] For step S105, please refer to Figure 4 In some implementations, step S105 may include the following steps:

[0086] S401: First remove the portion of the sacrificial layer 202 located between adjacent chips 102, such as... Figure 5 As shown in Figure (a); or a groove 204 may be formed within the sacrificial layer 202, the groove 204 surrounding the chip 102, as shown in Figure (a). Figure 5 As shown in Figure (b);

[0087] S402: Then remove the sacrificial layer 202 located between the chip 102 and the backplane 201 to bond the chip 102 to the backplane 201.

[0088] The chip transfer method described above can first remove the portion of the sacrificial layer 202 located between adjacent chips 102, while retaining the portion of the sacrificial layer 202 located below chip 102, so that there is no sacrificial layer 202 residue between adjacent chips 102. When the sacrificial layer 202 located between chip 102 and backplane 201 is removed, the sacrificial layer 202 will vaporize into gas and overflow from between adjacent chips 102, avoiding the thermal effect generated when removing the sacrificial layer 202, which would cause the sacrificial layer 202 between adjacent chips 102 to melt and accumulate, resulting in chip 102 tilting problem, and ensuring the consistency of the angle when transferring chip 102.

[0089] The chip transfer method described above can also form a groove 204 surrounding the chip 102 within the sacrificial layer 202. When the sacrificial layer 202 located between the chip 102 and the backplane 201 is removed, the sacrificial layer 202 will vaporize into gas and overflow from the groove 204. This avoids the thermal effect generated during the subsequent removal of the sacrificial layer 202, which would cause the sacrificial layer 202 between adjacent chips 102 to melt and accumulate, resulting in the chip 102 being skewed. This ensures the consistency of the chip 102 angle during chip transfer.

[0090] Regarding step S402, in some embodiments, such as Figure 6 As shown in Figures (a) and (b), the sacrificial layer 202 between the chip 102 and the backplate 201 can be removed by using, but not limited to, laser irradiation of the surface of the backplate 201 away from the chip 102, so that the chip 102 can contact the backplate 201. Figure 8 As shown.

[0091] Optionally, the chip 102 and the backplane 201 can be bonded together after applying pressure, heating and / or voltage, so that the bonding interface has good long-term stability. This application does not limit the specific form of the bonding process, as long as the chip 102 can be bonded to the surface of the backplane 201.

[0092] In some possible implementations, a laser can be used to periodically irradiate the surface of the backplane 201 away from the chip 102, such as... Figure 7 As shown in Figures (a) and (b), this allows the sacrificial layer 202 of a preset thickness to be removed sequentially until the sacrificial layer 202 between the chip 102 and the backplane 201 is completely removed, enabling the chip 102 to slowly descend to the surface of the backplane 201, as shown in Figures (a) and (b). Figure 8 As shown.

[0093] The chip transfer method described above removes the sacrificial layer 202 of a preset thickness one by one, so that the chip 102 can slowly and evenly descend to the surface of the backplate 201, avoiding problems such as skewing, flipping or residual adhesive caused by the rapid descent of the chip 102, and further ensuring the consistency of the angle when the chip 102 is transferred.

[0094] It is understood that this application does not limit the specific size of the preset thickness; the preset thickness can be adapted to the actual situation and working environment.

[0095] Please refer to the following for some possible implementations. Figure 2 The surface of the backplate 201 may have pads 203; at this time, the sacrificial layer 202 covers the surface of the backplate 201 where the pads 203 are formed and the pads 203. After the surface of the transient substrate 101 where the chip 102 is formed faces the sacrificial layer 202, the chip 102 and the pads 203 are aligned and distributed.

[0096] Based on the above implementation, in step S105, the sacrificial layer 202 located between the chip 102 and the backplane 201 is removed so that after the chip 102 is bonded to the backplane 201, the chip 102 is in contact with the pad 203 for bonding.

[0097] In chip transfer technology, it is typically necessary to transfer millions of chips onto a required backplane; the following section combines... Figure 9 Figures (a) to (e) provide a detailed description of the chip transfer method provided in some embodiments of this application, which implements multiple repeated chip transfers.

[0098] In some embodiments, the chip bonded to the backplane 201 is a first chip 301, such as... Figure 9 As shown in Figure (a).

[0099] Based on the above implementation method, after removing the sacrificial layer 202 and bonding the first chip 301 to the backplane 201, the following steps may also be included:

[0100] The second chip 302 is transferred using the same transfer steps as the first chip 301, such as... Figure 9 As shown in Figures (b) to (e), the second chip 302 is bonded to the backplane 201; specifically, the first chip 301 and the second chip 302 can be arranged periodically and alternately on the surface of the backplane 201.

[0101] The chip transfer method described above can transfer the second chip 302 by repeating the chip transfer method steps provided in any of the aforementioned embodiments, using the same transfer steps as the first chip 301. This allows for the transfer of other chips again, and can also transfer a new second chip 302 onto the backplane 201 surface where the first chip 301 has already been bonded, thus achieving multiple chip transfers.

[0102] Specifically, in some embodiments, during the process of repeating the chip transfer method steps provided in any of the foregoing embodiments to transfer the second chip 302 using the same transfer steps as the first chip 301, a sacrificial layer 202 may be formed on the surface of the backplate 201 to which the first chip 301 is bonded.

[0103] In some embodiments, the process of bonding the second chip 302 to the backplane 201 may include, but is not limited to, the following steps:

[0104] A transient substrate 101 is provided, and a second chip 302 is formed on the surface of the transient substrate 101, such as... Figure 9 As shown in Figure (a);

[0105] A backplane 201 is provided, on which a first chip 301 is bonded. A sacrificial layer 202 is formed on the surface of the backplane 201 on which the first chip 301 is bonded. Figure 9 As shown in Figure (a);

[0106] The surface of the transient substrate 101 on which the second chip 302 is formed faces the sacrificial layer 202, such as... Figure 9 As shown in Figure (a);

[0107] The second chip 302 to be transferred is separated from the transient substrate 101, so that the second chip 302 to be transferred falls vertically onto the surface of the sacrificial layer 202 away from the backplane 201, as shown. Figure 9 As shown in Figure (b);

[0108] Remove the sacrificial layer 202 to allow the second chip 302 to bond to the backplane 201, such as Figure 9 As shown in Figures (c) to (e).

[0109] In some possible implementations, the step of removing the sacrificial layer 202 to bond the second chip 302 to the backplane 201 may include the following steps:

[0110] Remove the portion of the sacrificial layer 202 located between adjacent second chips 302, or as follows: Figure 9 As shown in Figure (c), a groove 204 is formed in the sacrificial layer 202, and the groove 204 surrounds the second chip 302;

[0111] Remove the sacrificial layer 202 located between the second chip 302 and the backplane 201 to allow the second chip 302 to bond to the backplane 201, as shown below. Figure 9 As shown in Figure (d).

[0112] It should be noted that although the terms "first" and "second" may be used to describe the chip, this application should not be limited by these terms. These terms are only used to distinguish between a chip that has been bonded to the backplane 201 and a chip to be transferred to the backplane 201. Therefore, without departing from the teachings of this application, the first chip discussed above may be referred to as the second chip; for example, the first chip may be called the second chip, and similarly, the second chip may be called the first chip; and the first chip and the second chip may be the same type of chip or different types of chip, which is not specifically limited in this application.

[0113] It should also be noted that, in some embodiments, the optical characteristics and / or appearance quality of the chip 102 can be detected in advance by microphotoluminescence spectroscopy or micro-automated optical inspection (AOI) to generate mapping data. Targeted positioning and transfer are then performed on the qualified chips 102. In this way, the chips 102 transferred to the backplane 201 are all chips 102 with good appearance and good consistency of the main LED wavelength. Therefore, high-quality Micro LED display technology can be achieved based on the chip 102 using the chip transfer method provided in any of the above embodiments.

[0114] Based on the same inventive concept, this application also provides a display panel, including a back plate 201 and a plurality of chips 102 located on the surface of the back plate 201; wherein the plurality of chips 102 are transferred to the surface of the back plate 201 using the chip transfer method provided in any of the foregoing embodiments.

[0115] The aforementioned display panel includes multiple chips 102 that have been transferred to the surface of the backplane 201 using the chip transfer method provided in the aforementioned embodiments. Therefore, the display panel can also achieve the technical effects that the aforementioned chip transfer method can achieve, and will not be described in detail here.

[0116] It should be understood that the application of the present invention 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. A chip transfer method characterized by, include: A transient substrate is provided, and a chip is formed on the surface of the transient substrate; A backplate is provided, and a sacrificial layer is formed on the surface of the backplate; The surface of the transient substrate on which the chip is formed faces the sacrificial layer; The chip to be transferred is separated from the transient substrate so that the chip to be transferred is dropped vertically onto the surface of the sacrificial layer away from the backplane; Remove the sacrificial layer to allow the chip to bond to the backplane; The removal of the sacrificial layer includes: First, the portion of the sacrificial layer located between adjacent chips is removed, or a groove is formed within the sacrificial layer, the groove surrounding the chip; then, the sacrificial layer located between the chip and the backplane is removed, so that the chip and the backplane are bonded. The removal of the sacrificial layer located between the chip and the backplane includes: irradiating the surface of the backplane away from the chip with a laser to remove the sacrificial layer between the chip and the backplane, thereby bringing the chip into contact with the backplane.

2. The chip transfer method according to claim 1, wherein The sacrificial layer includes a photodegradable layer or a thermally degradable layer; the transient substrate includes a gallium nitride substrate.

3. The chip transfer method according to claim 1, wherein The thickness of the sacrificial layer is greater than the thickness of the chip.

4. The chip transfer method according to claim 1, wherein The step of separating the chip to be transferred from the transient substrate includes: The transient substrate is irradiated with a laser at a surface away from the chip to separate the chip to be transferred from the transient substrate.

5. The chip transfer method as described in claim 1, characterized in that, The backplate has pads on its surface, and the sacrificial layer covers the backplate surface on which the pads are formed and the pads. After the surface of the transient substrate on which the chip is formed faces the sacrificial layer, the chip is aligned and distributed with the pads. Remove the sacrificial layer located between the chip and the backplane so that after the chip is bonded to the backplane, the chip contacts and bonds to the pads.

6. The chip transfer method according to claim 1, wherein The step of using a laser to irradiate the surface of the backplane away from the chip to remove the sacrificial layer between the chip and the backplane includes: The backplane is periodically irradiated with a laser to remove the sacrificial layer of a preset thickness, until the sacrificial layer between the chip and the backplane is completely removed, so that the chip slowly descends to the surface of the backplane.

7. The chip transfer method according to any one of claims 1 to 6, wherein After the sacrificial layer is removed, the chip bonded to the backplane is the first chip; After bonding the first chip to the backplane, the process further includes: The second chip is transferred using the same transfer steps as the first chip, so that the second chip is bonded to the backplane; The first chip and the second chip are arranged at alternating intervals on the surface of the backplate.

8. A display panel, characterized by, It includes a backplane and a plurality of chips located on the surface of the backplane; wherein the plurality of chips are transferred to the surface of the backplane using the chip transfer method as described in any one of claims 1 to 7.

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