Method for transferring a chip

Abstract

The application provides a transfer method of a chip, comprising: arranging a plurality of light emitting chips on a substrate side of a substrate to be transferred; and controlling laser emitted by a laser source to irradiate the light emitting chips along an oblique direction, and an included angle between the oblique direction and a plane where the substrate is located is an acute angle. According to the embodiment of the application, the laser is controlled to irradiate the light emitting chips along the oblique direction, so that the force acting on the light emitting chips is obliquely incident on the light emitting chips to bombard the light emitting chips, thereby controlling the light emitting chips to splash away from the substrate in a specific direction range, and thus facilitating the subsequent collection of the light emitting chips.

Description

Technical Field

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

[0002] With the development of traditional flat panel displays and micro-projection displays, the promising mainstream core display technology—Micro-LED technology—is attracting increasing attention due to its significant performance advantages. Micro-LED can be considered a miniaturized LED that can be lit individually, offering advantages such as low energy consumption, high brightness, high definition, and long lifespan. It is poised to become a new display technology on par with organic light-emitting diode (OLED) displays. Summary of the Invention

[0003] This application provides a chip transfer method that can control the chip sputtering direction.

[0004] This application provides a chip transfer method, including:

[0005] Multiple light-emitting chips are disposed on one side of the substrate of the substrate to be transferred;

[0006] The laser emitted by the laser source is controlled to illuminate the light-emitting chip in an inclined direction, with the angle between the inclined direction and the plane where the substrate is located being an acute angle.

[0007] In some embodiments, the light-emitting chip has a first end and a second end opposite to each other in a first direction, the first direction being parallel to the plane of the substrate and the orthogonal projection of the laser source on the substrate being located on the side of the first end of the light-emitting chip away from the second end in the first direction.

[0008] In controlling the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction, the laser intensity gradually decreases as it is emitted towards different positions on the light-emitting chip in the direction from the first end to the second end.

[0009] In some embodiments, the laser intensity irradiated by the laser source on the light-emitting chip decreases linearly or by a gradient in the direction from the first end to the second end.

[0010] In some embodiments, in controlling the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction, lasers of different intensities are emitted to different positions of the light-emitting chip in a second direction;

[0011] The first direction intersects the second direction, and the plane formed by the first direction and the second direction is parallel to the plane containing the base.

[0012] In some embodiments, it also includes:

[0013] A collection device is provided, which collects the light-emitting chip that has detached from the substrate when the laser emitted by the laser source is directed to irradiate the light-emitting chip in an inclined direction. The collection device is located on the side of the light-emitting chip that is away from the laser source.

[0014] In some embodiments, in controlling the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction, the laser intensity range of the laser source emitted is 5mw-30mw.

[0015] In some embodiments, in controlling the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction:

[0016] The angle between the tilt direction and the base ranges from 30° to 70°.

[0017] In some embodiments, in controlling the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction, lasers of different intensities are emitted toward the light-emitting chips of different colors.

[0018] In some embodiments, the light-emitting chip includes a red light-emitting chip, and the laser intensity irradiating the red light-emitting chip is greater than the laser intensity irradiating other color light-emitting chips.

[0019] In some embodiments, the light-emitting chip includes a light-emitting layer and a conductive layer located on one side of the light-emitting layer. In controlling the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction, the laser is irradiated on the side of the light-emitting layer away from the conductive layer.

[0020] In some embodiments, the substrate to be transferred further includes an adhesive portion disposed between the light-emitting chip and the substrate, the adhesive portion being used to bond the substrate and the light-emitting chip;

[0021] The bonding portion includes multiple bonding sub-parts that coincide with the orthographic projection of the light-emitting chip onto the substrate. Each bonding sub-part has a fifth end and a sixth end opposite to each other in a first direction. The first direction is parallel to the plane of the substrate, and the orthographic projection of the laser source onto the substrate is located on the side of the fifth end away from the sixth end in the first direction.

[0022] In the direction from the fifth end to the sixth end, the adhesiveness of the adhesive sub-part gradually decreases.

[0023] In some embodiments, the adhesive portion includes photosensitive adhesive, and the adhesiveness of the adhesive portion decreases as the laser emitted by the laser source irradiates the light-emitting chip in an inclined direction.

[0024] This application provides a chip transfer method. By controlling a laser to irradiate a light-emitting chip in an inclined direction, the force acting on the light-emitting chip will bombard the chip at an inclined angle, thereby controlling the light-emitting chip to splash away from the substrate within a specific directional range, which is beneficial for subsequent collection of the light-emitting chip. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a flowchart of a chip transfer method provided in an embodiment of this application;

[0027] Figures 2a-2b This is a schematic diagram of the process structure of a chip transfer method provided in an embodiment of this application;

[0028] Figure 3 yes Figure 2b A structural diagram from another perspective;

[0029] Figure 4 This is a flowchart of another chip transfer method provided in the embodiments of this application;

[0030] Figure 5 This is a schematic diagram of the process structure of another chip transfer method provided in the embodiments of this application;

[0031] Figure 6 This is a schematic diagram of the process structure of another chip transfer method provided in the embodiments of this application.

[0032] Marker explanation:

[0033] 1. Substrate to be transferred; 11. Base; 12. Adhesive part; 121. Adhesive sub-part;

[0034] 2. Light-emitting chip; 21. Conductive layer; 211. First electrode; 212. Second electrode; 22. Light-emitting layer;

[0035] 3. Laser source;

[0036] 4. Collection device;

[0037] E1, first terminal; E2, second terminal; E3, third terminal; E4, fourth terminal; E5, fifth terminal; E6, sixth terminal;

[0038] α, included angle;

[0039] X, the first direction; Y, the second direction. Detailed Implementation

[0040] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application 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 intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0041] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0042] In recent years, the manufacturing process of micro LEDs has become increasingly sophisticated. Compared with traditional display panels, micro LEDs have many advantages such as smaller size, higher resolution, higher brightness, higher luminous efficiency, and lower power consumption. Therefore, they are considered to be the mainstream of next-generation display technology.

[0043] The fabrication process of miniature light-emitting diodes (LEDs) typically involves first thinning, miniaturizing, and arraying the LED structure to achieve a size of approximately 1 to 10 micrometers. Then, the miniature LEDs are transferred in batches onto a circuit board, and finally packaged. Specifically, this process involves first transferring the miniature LEDs from the growth substrate to a temporary substrate, and then transferring them from the temporary substrate to the circuit board.

[0044] After the miniature LEDs are transferred to the temporary substrate, each LED needs to be tested to determine its functionality. Damaged LEDs need to be removed from the temporary substrate using a laser. However, existing laser transfer methods struggle to control the detachment direction, resulting in LEDs scattering everywhere and making it difficult to collect the residue.

[0045] To resolve the above issues, please refer to Figure 1As shown in Figure 2, this application embodiment provides a chip transfer method, including:

[0046] S100: Multiple light-emitting chips are disposed on one side of the substrate of the substrate to be transferred.

[0047] In step S100, the light-emitting chip 2 includes, but is not limited to, a micro light-emitting diode, and the substrate 11 of the substrate to be transferred is used to support multiple light-emitting chips 2. Exemplarily, the light-emitting chip 2 includes a red light-emitting chip 2 for emitting red light, a blue light-emitting chip 2 for emitting blue light, and a green light-emitting chip 2 for emitting green light.

[0048] The substrate 1 to be transferred typically serves as a temporary substrate during the transfer of the light-emitting chip 2, acting as an intermediate carrier for the next transfer step. Since it is a temporary transfer, the interfacial adhesion between the light-emitting chip 2 and the substrate 11 can disappear under certain conditions, thus releasing the light-emitting chip 2. Optionally, a heat-release adhesive layer is provided between the substrate 11 and the light-emitting chip 2. By heating, the adhesive force of the heat-release adhesive layer can completely disappear without contaminating the transferred light-emitting chip 2.

[0049] S110: Controls the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction, with the angle between the inclined direction and the plane where the substrate is located being an acute angle.

[0050] In step S110, the light-emitting chip 2 is splattered off from the substrate 11 by laser irradiation. The laser irradiating the light-emitting chip 2 exerts a specific force on it, and the propagation direction of the laser is the direction of the external force acting on the chip 2. In the prior art, the laser source 3 is located directly above the light-emitting chip 2 and irradiates the side of the chip 2 facing away from the substrate 11 perpendicularly. Under the action of the laser, the chip 2 separates from the substrate 11 and sputters away from the transfer substrate 1. This method makes it difficult to control the sputtering direction of the chip 2, which is not conducive to subsequent recycling.

[0051] In this embodiment, the laser irradiates the light-emitting chip 2 at an inclined direction, so the force acting on the light-emitting chip 2 will bombard it at an inclined angle. When the laser emitted by the laser source 3 exceeds a certain intensity, the light-emitting chip 2 can be splashed away from the substrate 11 within a specific directional range, which is beneficial for the subsequent collection of the light-emitting chip 2.

[0052] Specifically, to achieve laser irradiation of the light-emitting chip 2 along an inclined direction, the projection of the laser source 3 onto the substrate 1 to be transferred and the projection of the light-emitting chip 2 onto the substrate 1 to be transferred need to be spaced apart along a first direction X, which is parallel to the surface of the substrate 11. Under the impact of the laser irradiation, the light-emitting chip 2 will splash away from the substrate 11 in a direction away from the laser source 3. This prevents the light-emitting chip 2 from splashing towards the laser source 3, thereby reducing the potential splashing range of the light-emitting chip 2 and facilitating subsequent collection.

[0053] It should be noted that, in this embodiment, the laser source 3 can be located on the same side as the light-emitting chip 2, thereby irradiating the side of the light-emitting chip 2 away from the substrate 11 with a laser. Alternatively, the laser source 3 can be located on the side of the substrate 11 away from the light-emitting chip 2, thereby irradiating the side of the light-emitting chip 2 facing the substrate 11 with a laser. This embodiment does not impose any restrictions on this.

[0054] Furthermore, the chip transfer method provided in this application embodiment can be used not only to transfer damaged light-emitting chips 2, but also to transfer other specific light-emitting chips 2. This application embodiment does not limit this.

[0055] In this embodiment, by controlling the laser to irradiate the light-emitting chip 2 in an inclined direction, the force acting on the light-emitting chip 2 will bombard the light-emitting chip 2 at an inclined angle, thereby controlling the light-emitting chip 2 to splash away from the substrate 11 within a specific directional range, which is beneficial for the subsequent collection of the light-emitting chip 2.

[0056] In some embodiments, in step S110, laser light with gradually decreasing intensity is emitted to different positions on the light-emitting chip 2 in a direction away from the laser source 3.

[0057] Compared to other transfer methods, laser transfer allows for precise control of the laser intensity at different locations. Based on this, this embodiment controls the laser emitted from the laser source 3, ensuring that the light-emitting chip 2 experiences different laser intensities at different locations along the first direction X.

[0058] Specifically, the light-emitting chip 2 includes a first end E1 and a second end E2 in the first direction X. The first end E1 is positioned closer to the laser source 3 than the second end E2. In the direction from the first end E1 to the second end E2, the laser source 3 emits laser light with a gradually decreasing intensity at different positions on the light-emitting chip 2, so that the laser intensity received by the light-emitting chip 2 gradually decreases. That is, the laser intensity received by the light-emitting chip 2 is greater at the position closer to the first end E1 and less at the position closer to the second end E2.

[0059] This laser irradiation method makes it easier for the light-emitting chip 2 to splash away from the substrate 11 in a direction away from the laser source 3, and by controlling the laser intensity value received by the light-emitting chip 2 at different positions in the first direction X, the splashing distance of the light-emitting chip 2 in the first direction X can be precisely controlled.

[0060] In some embodiments, the laser intensity of the laser source 3 irradiating the light-emitting chip 2 decreases linearly or gradually in the direction from the first end E1 to the second end E2.

[0061] In this embodiment, the laser intensity received by the light-emitting chip 2 at different positions in the first direction X is further limited to make it change linearly or in a gradient manner, thereby reducing the difficulty of controlling the laser while precisely controlling the splashing distance of the light-emitting chip 2 in the first direction X.

[0062] In some embodiments, please refer to Figures 1 to 3 In step S110, lasers of different intensities are emitted to different positions on the light-emitting chip 2 along the second direction Y. The first direction X intersects the second direction Y, and the plane formed by the first direction X and the second direction Y is parallel to the plane containing the substrate 11.

[0063] In addition to generating a splash distance in the first direction X, the light-emitting chip 2 also generates a certain splash distance in the second direction Y. For example, the first direction X is perpendicular to the second direction Y. To better control the splash distance of the light-emitting chip 2 in the second direction Y, embodiments of this application differentiate the intensity of the laser irradiating the light-emitting chip 2 in the second direction Y, thereby achieving control over the splash distance of the light-emitting chip 2 in the second direction Y.

[0064] For example, the light-emitting chip 2 has a third end E3 and a fourth end E4 opposite to each other in the second direction Y, with the third end E3 being closer to the laser source 3 than the fourth end E4. In the direction from the third end E3 to the fourth end E4, the laser intensity irradiated by the laser source 3 on the light-emitting chip 2 gradually decreases. Optionally, in the direction from the third end E3 to the fourth end E4, the laser energy irradiated by the laser source 3 on the light-emitting chip 2 decreases linearly or with a gradient.

[0065] In summary, this embodiment of the application controls the splashing distance of the light-emitting chip 2 in the first direction X by controlling the laser intensity received on the light-emitting chip 2 in the second direction Y; and controls the splashing distance of the light-emitting chip 2 in the second direction Y by controlling the laser intensity received on the light-emitting chip 2 in the second direction Y. With the combined effect of these two methods, the transfer method provided by this embodiment can precisely control the splashing direction and splashing distance of the light-emitting chip 2, thereby further reducing the difficulty of subsequent collection.

[0066] In some embodiments, please refer to Figure 4 and Figure 5 The transfer methods also include:

[0067] S120: Provides a collection device.

[0068] In step S120, the collecting device 4 is positioned on the side of the light-emitting chip 2 away from the laser source 3. In step S110, the collecting device 4 is used to collect the light-emitting chips 2 that have detached from the substrate 11. As described above, the light-emitting chips 2 will splash away from the substrate 11 in a direction away from the laser source 3. Based on this, this embodiment of the application positions the collecting device 4 on the side of the light-emitting chip 2 away from the laser source 3, enabling the collecting device 4 to directly collect all or most of the splashed-out light-emitting chips 2, thus improving collection efficiency.

[0069] In some embodiments, in step S110, the laser intensity emitted by the laser source 3 is in the range of 5mw-30mw.

[0070] The intensity of the laser determines the splashing distance of the light-emitting chip 2. If the laser intensity is too low, the force acting on the light-emitting chip 2 is insufficient to overcome the adhesion between it and the substrate 11, making it impossible to collect the splashes from the light-emitting chip 2. Conversely, if the laser intensity is too high, the force on the light-emitting chip 2 will be too great, leading to problems such as excessively long splashing distances or excessively high splashing speeds, which is also detrimental to collection. Furthermore, when the laser energy is too high, it will affect surrounding light-emitting chips 2, potentially causing damage to them.

[0071] Therefore, in this embodiment, the laser intensity range is set between 5mw and 30mw. This satisfies the requirement of splashing while effectively controlling the splashing distance, thereby facilitating subsequent collection.

[0072] In some embodiments, in step S110, the angle α between the tilting direction and the base 11 ranges from 30° to 70°.

[0073] If the angle α between the tilt direction and the substrate 11 is too small, it means that the distance between the laser source 3 and the substrate 1 to be transferred in the thickness direction of the substrate 11 is too small. The laser source 3 is likely to affect the nearby light-emitting chip 2, causing it to be damaged. Therefore, in order to avoid the risk of this problem, the embodiment of this application sets the angle α between the tilt direction and the substrate 11 to be not less than 30°, thereby increasing the distance between the laser source 3 and the substrate 1 to be transferred in the thickness direction.

[0074] If the angle α between the tilt direction and the substrate 11 is too large, most of the laser energy consumed by the laser source 3 will be used to increase the maximum sputtering height of the light-emitting chip 2, while the sputtering distance of the light-emitting chip 2 will be too small. To avoid this problem, the embodiments of this application also set the angle α between the tilt direction and the substrate 11 to no more than 70°, thereby reducing the loss and waste of laser energy.

[0075] In some embodiments, in step S110, lasers of different intensities are emitted to light-emitting chips 2 of different colors.

[0076] The light-emitting chip 2 is typically used to achieve specific display effects, and therefore is usually implemented by using multiple color light-emitting chips 2 in combination. Optionally, the light-emitting chip 2 includes a red light-emitting chip 2 for emitting red light, a green light-emitting chip 2 for emitting green light, and a blue light-emitting chip 2 for emitting blue light.

[0077] Different colored light-emitting chips 2 have different absorption capacities for laser light. Therefore, when laser light of the same intensity shines on different colored light-emitting chips 2, the magnitude of the force exerted by the laser on the different colored light-emitting chips 2 is not the same. Therefore, for different colored light-emitting chips 2, this embodiment of the application makes the corresponding laser intensities different, so that the magnitude of the force exerted on the different colored light-emitting chips 2 is as consistent as possible, thereby ensuring that the splashing distance of each light-emitting chip 2 is the same, which is beneficial for subsequent collection.

[0078] In some embodiments, the laser intensity irradiating the red light-emitting chip 2 is greater than the laser intensity irradiating the light-emitting chips 2 of other colors.

[0079] For the red light-emitting chip 2, its light transmittance to laser light is the strongest, and its absorption capacity is the weakest. Therefore, the force generated by laser light irradiating the red light-emitting chip 2 with the same laser intensity is the smallest. Therefore, this embodiment of the application compensates for the red light-emitting chip 2 so that the laser intensity it receives is greater than that of the other color light-emitting chips 2, thereby ensuring that the splashing distance of the red light-emitting chip 2 is similar to that of the other color light-emitting chips 2.

[0080] In some embodiments, please refer to Figure 6 The light-emitting chip 2 includes a light-emitting layer 22 and a conductive layer 21 located on one side of the light-emitting layer 22. In step S110, laser light is irradiated onto the light-emitting layer 22 away from the conductive layer 21.

[0081] The light-emitting layer 22 is used to realize the light-emitting function of the light-emitting chip 2, and the conductive layer 21 is used to connect the light-emitting layer 22 to the external circuit, thereby controlling the light-emitting layer 22 to emit light or turn off. For example, the conductive layer 21 includes a first electrode 211 and a second electrode 212.

[0082] In all the light-emitting chips 2 located on the substrate 11, the conductive layer 21 is usually located on the same side of the light-emitting layer 22. However, during the laser transfer process, when the laser source 3 irradiates a specific light-emitting chip 2, the light-emitting chips 2 located around that light-emitting chip 2 are at risk of being irradiated or indirectly affected by the laser source 3. The conductive layer 21 is more prone to failure than the light-emitting layer 22. Therefore, in this embodiment, the laser is irradiated on the side of the light-emitting layer 22 away from the conductive layer 21, thereby avoiding the influence of the laser on the conductive layer 21 of the light-emitting chip 2, and thus indirectly improving the yield.

[0083] In some embodiments, such as Figure 6 As shown, the substrate 1 to be transferred also includes an adhesive portion 12 disposed between the light-emitting chip 2 and the substrate 11. The adhesive portion 12 is used to bond the substrate 11 and the light-emitting chip 2. The adhesive portion 12 includes a plurality of adhesive sub-portions 121 that coincide with the orthographic projection of the light-emitting chip 2 onto the substrate 11. The adhesive sub-portions 121 have opposing fifth ends E5 and sixth ends E6 in the first direction X. The orthographic projection of the substrate 11 where the laser source 3 is located is located on the side of the fifth end E5 away from the sixth end E6 in the first direction X. Among them, the adhesiveness of the adhesive sub-portions 121 gradually decreases in the direction from the fifth end E5 to the sixth end E6.

[0084] The adhesive sub-part 121 in the adhesive part 12 is used to bond and fix the light-emitting chip 2 to the substrate 11, reducing the risk of relative movement between the light-emitting chip 2 and the substrate 11.

[0085] The farther away from the laser source 3, the weaker the laser intensity received by the light-emitting chip 2. Therefore, stronger laser energy is often required to ensure that the light-emitting chip 2 detaches from the substrate 11. Based on this, the adhesiveness of the adhesive sub-part 121 is set to gradually decrease in the direction away from the laser source 3, that is, the adhesiveness of the adhesive sub-part 121 is lower the farther away from the laser source 3. This design can further reduce the difficulty of the light-emitting chip 2 detaching from the substrate 11, thereby reducing the laser intensity and energy consumption to a certain extent.

[0086] It should be noted that the number of adhesive sub-parts 121 is the same as the number of light-emitting chips 2, and their positions correspond. The structures of each adhesive sub-part 121 are the same, that is, the trend of adhesiveness change is the same.

[0087] In some embodiments, the adhesive portion 12 includes photosensitive adhesive, and in step S110, the adhesiveness of the adhesive portion 12 decreases as it is irradiated by the laser source 3.

[0088] The adhesiveness of the photosensitive adhesive changes with the light intensity. In this embodiment, the adhesiveness of the adhesive part 12 is set to decrease with the irradiation of the laser source 3. As a result, after laser irradiation, the adhesion between the light-emitting chip 2 and the adhesive part 12 decreases, thereby enabling the collection of splashes from the light-emitting chip 2 under a smaller laser intensity, thereby further reducing energy consumption.

[0089] While the embodiments disclosed in this application are as described above, the content is merely for the purpose of facilitating understanding of this application and is not intended to limit the invention. Any person skilled in the art to which this application pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed in this application; however, the scope of protection of this application shall still be determined by the scope defined in the appended claims.

[0090] The above description is merely a specific embodiment of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, substitutions for other connection methods described above can be made by referring to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application.

Claims

1. A chip transfer method, characterized in that, include: Multiple light-emitting chips are disposed on one side of the substrate of the substrate to be transferred; The laser emitted by the laser source is controlled to illuminate the light-emitting chip in an inclined direction, wherein the angle between the inclined direction and the plane where the substrate is located is an acute angle; In the process of controlling the laser emitted by the laser source to irradiate the light-emitting chip in an inclined direction, the laser intensity emitted by the laser source is in the range of 5mw-30mw, and the angle between the inclined direction and the substrate is in the range of 30°-70°.

2. The transfer method according to claim 1, characterized in that, The light-emitting chip has a first end and a second end opposite to each other in a first direction, the first direction being parallel to the plane of the substrate and the orthogonal projection of the laser source on the substrate being located on the side of the first end away from the second end in the first direction; In controlling the laser source to emit laser light in an inclined direction to irradiate the light-emitting chip, the laser light emitted from the first end to the second end is emitted at different positions on the light-emitting chip with a gradually decreasing intensity.

3. The transfer method according to claim 2, characterized in that, In the direction from the first end to the second end, the laser intensity of the laser source illuminating the light-emitting chip decreases linearly or by a gradient.

4. The transfer method according to claim 2, characterized in that, In controlling the laser source to emit laser light along an inclined direction to irradiate the light-emitting chip, lasers of different intensities are emitted to different positions of the light-emitting chip in a second direction; Wherein, the first direction intersects the second direction, and the plane formed by the first direction and the second direction is parallel to the plane where the base is located.

5. The transfer method according to claim 4, characterized in that, The first direction is perpendicular to the second direction.

6. The transfer method according to claim 1, characterized in that, Also includes: Provide collection devices; In the process of the laser emitted by the controlled laser source irradiating the light-emitting chip in an inclined direction, the collecting device collects the light-emitting chip that has detached from the substrate, and the collecting device is disposed on the side of the light-emitting chip away from the laser source.

7. The transfer method according to claim 1, characterized in that, In controlling the laser source to emit laser light along an inclined direction to illuminate the light-emitting chip, lasers of different intensities are emitted towards the light-emitting chip of different colors.

8. The transfer method according to claim 7, characterized in that, The light-emitting chip includes a red light-emitting chip, and the laser intensity of the laser source illuminating the red light-emitting chip is greater than the laser intensity illuminating the light-emitting chips of other colors.

9. The transfer method according to claim 1, characterized in that, The light-emitting chip includes a light-emitting layer and a conductive layer located on one side of the light-emitting layer. When the laser emitted by the control laser source irradiates the light-emitting chip in an inclined direction, the laser is irradiated on the side of the light-emitting layer that is away from the conductive layer.

10. The transfer method according to claim 1, characterized in that, The substrate to be transferred further includes an adhesive portion disposed between the light-emitting chip and the substrate, the adhesive portion being used to bond the substrate and the light-emitting chip; The adhesive portion includes a plurality of adhesive sub-parts that coincide with the orthographic projection of the light-emitting chip on the substrate. The adhesive sub-parts have a fifth end and a sixth end opposite to each other in a first direction. The first direction is parallel to the plane where the substrate is located, and the orthographic projection of the laser source on the substrate is located on the side of the fifth end away from the sixth end in the first direction. In the direction from the fifth end to the sixth end, the adhesiveness of the adhesive sub-part gradually decreases.

11. The transfer method according to claim 10, characterized in that, The adhesive portion includes photosensitive adhesive, and when the laser emitted by the control laser source irradiates the light-emitting chip in an inclined direction, the adhesiveness of the adhesive portion decreases as the laser source irradiates it.

Images