Chip transfer method, driving substrate and display panel

Abstract

The invention belongs to the technical field of display, and particularly relates to a chip transfer method, a driving substrate and a display panel, and the chip transfer method comprises the steps that a transfer substrate and a driving substrate are provided, the transfer substrate comprises a first substrate and a light-emitting chip, the driving substrate comprises a second substrate, and a driving electrode, an expansion layer and a hot melt adhesive layer which are positioned on the same side of the second substrate; the expansion layer is arranged on at least one side of the driving electrode, and the volume of the expansion layer can be expanded under specific illumination; the hot melt adhesive layer is in contact with the expansion layer and can be melted under specific illumination; the hot melt adhesive layer at least covers the driving electrode, and the orthographic projection of the hot melt adhesive layer on the second substrate covers the orthographic projection of the expansion layer on the second substrate. According to the invention, the expansion layer is arranged on at least one side of the driving electrode, so that the characteristic that the expansion layer expands in volume under specific illumination is utilized, and the problem that the position of the light-emitting chip deviates when the light-emitting chip is transferred due to melting of the hot melt adhesive layer on the driving substrate is reduced or avoided.

Description

Technical Field

[0001] The present disclosure belongs to the field of display technology, and specifically relates to a chip transfer method, a driving substrate and a display panel. Background Art

[0002] In the existing display panel technology, the common mass transfer technology is laser transfer technology, which uses laser to release the light-emitting chip from the transfer substrate and then transfer it to the driving substrate in batches. Laser transfer technology has high transfer efficiency and flexible single transfer area. Since there is a certain distance between the transfer substrate and the driving substrate during the transfer process, it is easy to cause the landing point of the micro-light-emitting device to shift during the transfer process, affecting the accuracy of the laser transfer, and thus affecting the manufacturing yield of the display panel. Summary of the invention

[0003] The purpose of the present application is to provide a chip transfer method, a driving substrate and a display panel, which can reduce or avoid the possibility of positional deviation during the transfer of the light-emitting chip by setting an expansion layer, thereby improving the accuracy and success rate of the transfer of the light-emitting chip.

[0004] The present disclosure provides a chip transfer method, the chip transfer method comprising:

[0005] Providing a transfer substrate, the transfer substrate comprising a first substrate and a light-emitting chip on the first substrate;

[0006] A driving substrate is provided, the driving substrate comprising a second substrate and a driving electrode, an expansion layer and a hot melt adhesive layer located on the same side of the second substrate; the expansion layer is arranged on at least one side of the driving electrode, and the expansion layer can expand in volume under specific light; the hot melt adhesive layer is in contact with the expansion layer, and the hot melt adhesive layer can melt under the specific light; the hot melt adhesive layer at least covers the driving electrode, and the orthographic projection of the hot melt adhesive layer on the second substrate covers the orthographic projection of the expansion layer on the second substrate;

[0007] Aligning the transfer substrate and the drive substrate so that the light-emitting chip is correspondingly bound to the drive electrode through the hot-melt adhesive layer;

[0008] A specific light irradiation technique is used to irradiate a side of the first substrate facing away from the light emitting chip, so as to separate the first substrate from the light emitting chip.

[0009] In an exemplary embodiment of the present disclosure, the method for forming the driving substrate includes:

[0010] Providing a second substrate;

[0011] forming the driving electrode on the second substrate;

[0012] forming the expansion layer on the second substrate;

[0013] forming the hot melt adhesive layer on the second substrate, wherein the hot melt adhesive layer covers the driving electrode and the expansion layer;

[0014] Wherein, if the hot melt adhesive layer melts under the specific light and forms a vacancy, the expansion layer corresponding to the vacancy can expand in volume under the specific light to fill the vacancy.

[0015] In an exemplary embodiment of the present disclosure, after forming the driving electrode and before forming the expansion layer, the chip transfer method further includes: forming a cushioning layer on the second substrate, wherein the cushioning layer is located on a side of the expansion layer close to the second substrate, so that a side of the expansion layer facing away from the second substrate is not lower than a side of the driving electrode facing away from the second substrate.

[0016] In an exemplary embodiment of the present disclosure, the expansion layer is made of an electrodeformable material, and the cushioning layer is made of a photoelectric material.

[0017] The cushioning layer can convert light energy into electrical energy, and the expansion layer can expand in volume under the action of the electrical energy generated by the cushioning layer.

[0018] In an exemplary embodiment of the present disclosure, the hot melt adhesive layer includes a first adhesive layer and a second adhesive layer; and the method for forming the driving substrate includes:

[0019] Providing a second substrate;

[0020] forming the driving electrode on the second substrate;

[0021] forming the first adhesive layer on the second substrate;

[0022] forming the expansion layer on a side of the first adhesive layer facing away from the second substrate;

[0023] forming a second adhesive layer on a side of the expansion layer away from the first adhesive layer, wherein the second adhesive layer at least covers the expansion layer;

[0024] Wherein, if the hot melt adhesive layer melts under the specific light and forms a vacancy, the expansion layer corresponding to the vacancy can expand in volume under the specific light to fill the vacancy.

[0025] In an exemplary embodiment of the present disclosure, the method for forming the driving substrate includes:

[0026] Providing a second substrate;

[0027] forming the driving electrode on the second substrate;

[0028] forming the hot melt adhesive layer on the second substrate, wherein the hot melt adhesive layer covers the driving electrode and the second substrate;

[0029] The expansion layer is formed on a side of the hot melt adhesive layer facing away from the second substrate.

[0030] In an exemplary embodiment of the present disclosure, the expansion layer includes a plurality of expansion structures, each of the expansion structures is arranged at intervals, and the plurality of expansion structures are arranged around the outer circumference of the driving electrode.

[0031] The present disclosure provides a driving substrate, comprising:

[0032] a second substrate;

[0033] A driving electrode, located on the second substrate;

[0034] The expansion layer is located on the same side of the second substrate as the driving electrode, and the expansion layer is arranged on at least one side of the driving electrode; the expansion layer can expand in volume under specific light.

[0035] In an exemplary embodiment of the present disclosure, the driving substrate includes a hot melt adhesive layer that can melt under the specific light, the hot melt adhesive layer is in contact with the expansion layer, the hot melt adhesive layer at least covers the driving electrode, and the orthographic projection of the hot melt adhesive layer on the second substrate covers the orthographic projection of the expansion layer on the second substrate.

[0036] The present disclosure provides a display panel, comprising a plurality of light-emitting chips arranged in an array and spaced apart from each other, and any one of the driving substrates described above, wherein the light-emitting chip is correspondingly bound to a side of the driving electrode away from the second substrate.

[0037] In an exemplary embodiment of the present disclosure, the expansion layer has a light-shielding property, and the side of the expansion layer facing away from the second substrate is not lower than the side of the driving electrode facing away from the second substrate; when the light-emitting chip emits light, the expansion layer can expand in volume to block the light from one light-emitting chip to another adjacent light-emitting chip.

[0038] This application scheme has the following beneficial effects:

[0039] The present invention provides an expansion layer on at least one side of the driving electrode and makes the expansion layer contact with the hot melt adhesive layer. The expansion layer can expand in volume under specific light, thereby reducing or avoiding the problem of position displacement when the light-emitting chip is transferred due to the melting of the hot melt adhesive layer on the driving substrate.

[0040] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0041] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0043] Figure 1 Schematic diagram of the chip transfer method in the embodiment of the present disclosure.

[0044] Figure 2 It is a schematic diagram of the cross-sectional structure of the driving substrate when the expansion layer contacts the second substrate in the embodiment of the present disclosure.

[0045] Figure 3 It is a schematic cross-sectional structure diagram of a driving substrate when the expansion layer is connected to the cushioning layer in the embodiment of the present disclosure.

[0046] Figure 4 It is another cross-sectional structural schematic diagram of the driving substrate when the expansion layer is connected to the cushioning layer in the embodiment of the present disclosure.

[0047] Figure 5 It is a schematic diagram of the cross-sectional structure of laser precision offset in the related technology.

[0048] Figure 6 for Figure 5 Schematic diagram of the cross-sectional structure of the hot melt adhesive layer volatilizing the adhesive solvent under laser irradiation.

[0049] Figure 7 To remove Figure 6 Schematic diagram of the cross-sectional structure of the light-emitting chip and the driving electrode behind the hot melt adhesive layer.

[0050] Figure 8 It is a schematic cross-sectional structure diagram of an expansion layer disposed between the first adhesive layer and the second adhesive layer in an embodiment of the present disclosure.

[0051] Fig. 9 for Figure 8 Schematic diagram of the cross-sectional structure of the hot melt adhesive layer volatilizing the adhesive solvent under laser irradiation.

[0052] Fig.10 for Fig. 9 Schematic diagram of the cross-sectional structure of the volume expansion of the expansion layer.

[0053] Fig.11 for Figure 8 A schematic cross-sectional structure diagram of a structure in which the expansion layer is arranged as a plurality of expansion structures arranged at intervals.

[0054] Fig.12 It is a schematic cross-sectional structure diagram of an expansion layer disposed on a side of the hot melt adhesive layer away from the second substrate in an embodiment of the present disclosure.

[0055] Fig.13 for Fig.12 A schematic cross-sectional structure diagram of a structure in which the expansion layer is arranged as a plurality of expansion structures arranged at intervals.

[0056] Fig.14 for Fig.13 Schematic diagram of the cross-sectional structure of the expansion structure when the volume expands.

[0057] Fig.15 For Figure 2 Schematic diagram of the cross-sectional structure of the driving substrate when the expansion layer is covered with a hot melt adhesive layer.

[0058] Fig.16 For Figure 3 Schematic diagram of the cross-sectional structure of the driving substrate when the expansion layer is covered with a hot melt adhesive layer.

[0059] Fig.17 For Figure 4 Schematic diagram of the cross-sectional structure of the driving substrate when the expansion layer is covered with a hot melt adhesive layer.

[0060] Description of reference numerals:

[0061] 1. transfer substrate; 11. first substrate; 12. light emitting chip; 121. main body; 122. connecting electrode; 13. adhesive layer;

[0062] 2. driving substrate; 21. second substrate; 22. driving electrode; 23. expansion layer; 24. hot melt adhesive layer; 241. first adhesive layer; 242. second adhesive layer; 25. padding layer. DETAILED DESCRIPTION

[0063] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be more comprehensive and complete and will fully convey the concept of the example embodiments to those skilled in the art.

[0064] In addition, the described features, structures or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the present disclosure.

[0065] The present disclosure is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the technical features involved in the various embodiments of the present disclosure described below can be combined with each other as long as they do not conflict with each other. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and should not be understood as limiting the present disclosure.

[0066] refer to Figures 1 to 4 as well as Figures 8 to 17 As shown, the present disclosure provides a chip transfer method, the chip transfer method comprising:

[0067] S1. Provide a transfer substrate, wherein the transfer substrate comprises a first substrate and a light-emitting chip on the first substrate.

[0068] S2. Provide a driving substrate, the driving substrate comprising a second substrate and a driving electrode, an expansion layer and a hot melt adhesive layer located on the same side of the second substrate; the expansion layer is arranged on at least one side of the driving electrode, and the expansion layer can expand in volume under specific lighting; the hot melt adhesive layer is in contact with the expansion layer, and the hot melt adhesive layer can melt under specific lighting; the hot melt adhesive layer at least covers the driving electrode, and the orthographic projection of the hot melt adhesive layer on the second substrate covers the orthographic projection of the expansion layer on the second substrate.

[0069] S3, aligning the transfer substrate and the driving substrate so that the light-emitting chip is correspondingly bound to the driving electrode through the hot-melt adhesive layer.

[0070] S4. Using a specific lighting technique to illuminate the side of the first substrate facing away from the light-emitting chip, so as to separate the first substrate from the light-emitting chip.

[0071] In the embodiments of the present disclosure, the materials of the first substrate 11 and the second substrate 21 may be silicon (Si), sapphire (Al2O3), silicon carbide (SiC), etc., but are not limited thereto. The first substrate 11 and the second substrate 21 may be formed of materials other than silicon, sapphire, and silicon carbide, which may also be included in the embodiments of the present disclosure.

[0072] It should be noted that the first substrate 11 in the present disclosure may be a growth substrate for forming the light emitting chip 12. However, it is not limited thereto, and the first substrate 11 may also be a temporary substrate for carrying the light emitting chip 12 during the chip transfer process.

[0073] The light emitting chip 12 may include a main body 121 and a connection electrode 122 connected to the upper surface of the main body 121 . The connection electrode 122 is used to connect to the driving electrode 22 on the driving substrate 2 to emit light after obtaining a voltage.

[0074] It should be noted that the transfer substrate 1 may include one light emitting chip 12, but is not limited thereto. The transfer substrate 1 may also include multiple light emitting chips 12, and the multiple light emitting chips 12 may be arranged in an array and spaced apart on the first substrate 11. The number and arrangement of the light emitting chips 12 on the first substrate 11 may be set according to specific circumstances.

[0075] In addition, an adhesive layer 13 may be provided on the first substrate 11 . The adhesive layer 13 may cover the entire first substrate 11 . The light emitting chip 12 is bonded to the first substrate 11 through the adhesive layer 13 .

[0076] In the disclosed embodiment, one driving electrode 22 may be disposed on the second substrate 21 , but the present invention is not limited thereto. A plurality of driving electrodes 22 may be disposed on the second substrate 21 , depending on actual conditions.

[0077] For example: when a plurality of light-emitting chips 12 need to be transferred from a transfer substrate 1 to a driving substrate 2, or when a plurality of transfer substrates 1 need to transfer the light-emitting chips 12 to the same driving substrate 2, a plurality of driving electrodes 22 can be set on the driving substrate 2 to correspond to the light-emitting chips 12 on the transfer substrate 1.

[0078] The hot melt adhesive layer 24 in the present disclosure may be light-transmissive. The expansion layer 23 in the present disclosure is disposed on at least one side of the driving electrode 22, which may mean that the expansion layer 23 is disposed around the outer side of the driving electrode 22, but is not limited thereto, and may also mean that the expansion layer 23 is disposed on a portion of the outer peripheral side of the driving electrode 22.

[0079] Specifically, the manufacturing material of the expansion layer 23 may include expansion materials such as epoxy resin, acrylic resin, polyurethane, mixed ion perovskite film, etc. Under specific light, the expansion material undergoes lattice expansion, and the atomic spacing in the expansion material increases, thereby increasing the overall volume of the expansion layer 23.

[0080] The present disclosure utilizes the volume expansion property of the expansion layer 23 under specific light to reduce or avoid the problem of positional displacement of the light-emitting chip 12 during transfer caused by the melting of the hot melt adhesive layer 24 on the driving substrate 2, thereby improving the transfer accuracy and transfer yield of the light-emitting chip 12.

[0081] It should be noted that the specific light irradiation mentioned above may refer to a laser that peels off the light emitting chip 12 from the first substrate 11, but is not limited thereto. The specific light irradiation may also refer to a laser that separates the light emitting chip 12 from the corresponding bound driving electrode 22 when repairing a faulty light emitting chip 12 transferred to the driving substrate 2. At this time, the specific light irradiation may cause the expansion layer 23 to expand in volume and melt the hot melt adhesive layer 24.

[0082] In addition, when the expansion layer 23 is disposed in the display panel, the expansion layer 23 may also expand in volume under the action of the emitted light of the light emitting chip 12 in the display panel.

[0083] In the embodiment of the present disclosure, the manufacturing material of the expansion layer 23 may also include a light shielding material. Under the illumination of the light emitting chip 12, the expansion layer 23 expands in volume, thereby increasing the light shielding area of ​​the expansion layer 23, thereby reducing or avoiding the possibility that the emitted light of one light emitting chip 12 irradiates another adjacent light emitting chip 12, thereby reducing or avoiding the problem of cross-color between the light emitting chips 12 in the display panel.

[0084] In the embodiment of the present disclosure, the orthographic projection of the light-emitting chip 12 on the second substrate 21 may coincide with the orthographic projection of the driving electrode 22 bound thereto on the second substrate 21, but is not limited thereto. The orthographic projection of the driving electrode 22 on the second substrate 21 may also be located within the orthographic projection of the light-emitting chip 12 bound thereto on the second substrate 21.

[0085] like Figures 2 to 4 As shown, the method for forming the driving substrate 2 in the embodiment of the present disclosure may include: providing a second substrate 21, and forming a driving electrode 22 on the second substrate 21. After forming the driving electrode 22, first forming an expansion layer 23 on the second substrate 21, and then forming a hot melt adhesive layer 24 on the second substrate 21. The formed hot melt adhesive layer 24 is in contact with the expansion layer 23, and the hot melt adhesive layer 24 covers the driving electrode 22 and the expansion layer 23.

[0086] When the hot melt adhesive layer 24 melts under specific lighting and forms a vacancy, the expansion layer 23 corresponding to the vacancy can expand in volume under specific lighting to fill the vacancy of the hot melt adhesive layer 24 .

[0087] For example, Figures 5 to 7As shown, after the transfer substrate 1 and the driving substrate 2 are aligned, the light-emitting chip 12 on the transfer substrate 1 is bonded to the hot-melt adhesive layer 24 of the driving substrate 2. The laser is used to irradiate the side of the first substrate 11 away from the light-emitting chip 12, so that the light-emitting chip 12 and the first substrate 11 are peeled off. When the laser precision is offset, part of the laser is irradiated to the hot-melt adhesive layer 24 outside the light-emitting chip 12. Since the hot-melt adhesive layer 24 has a certain wettability, the hot-melt adhesive layer 24 will be heated during laser irradiation, and the irradiated area of ​​the hot-melt adhesive layer 24 will melt, and the adhesive solvent in the hot-melt adhesive layer 24 will evaporate and form a vacancy, which will cause the adhesive around the vacant area of ​​the hot-melt adhesive layer 24 to flow, thereby causing the light-emitting chip 12 to be transferred to the driving substrate 2 and bound to the driving electrode 22 on the driving substrate 2. Thereby affecting the transfer accuracy and transfer yield of the light-emitting chip 12.

[0088] In order to avoid the above situation, the embodiment of the present disclosure sets an expansion layer 23 on the driving substrate 2. The expansion layer 23 is located on at least one side of the driving electrode 22, and the expansion layer 23 can expand in volume under laser irradiation. When the laser that peels the light-emitting chip 12 from the first substrate 11 has a precision deviation, and the laser irradiates the hot melt adhesive layer 24, the adhesive material in the irradiated area of ​​the hot melt adhesive layer 24 melts. At the same time, the laser irradiates the expansion layer 23 through the hot melt adhesive layer 24, and the expansion layer 23 expands in volume under the irradiation of the laser to fill the vacant area of ​​the hot melt adhesive layer 24, reducing or avoiding the flow of adhesive material around the vacant area of ​​the hot melt adhesive layer 24 to the place where the solvent evaporates, reducing or avoiding the risk of position deviation of the light-emitting chip 12 due to the flow of adhesive material of the hot melt adhesive layer 24, thereby improving the transfer accuracy of the light-emitting chip 12 and the transfer yield of the light-emitting chip 12.

[0089] It should be noted that when the expansion layer 23 in the embodiment of the present disclosure expands, the side of the expanded portion of the expansion layer 23 facing away from the second substrate 21 can be flush with the side of the hot melt adhesive layer 24 facing away from the second substrate 21, or the side of the expanded portion of the expansion layer 23 facing away from the second substrate 21 can be higher than the side of the hot melt adhesive layer 24 facing away from the second substrate 21, so that the expanded portion of the expansion layer 23 can be used to completely fill the vacant area of ​​the hot melt adhesive layer 24 to reduce or avoid the flow of the adhesive in the hot melt adhesive layer 24.

[0090] However, it is not limited to this. In the embodiment of the present disclosure, the expanded portion of the expansion layer 23 may also be slightly lower than the side of the hot melt adhesive layer 24 facing away from the second substrate 21. The expanded portion of the expansion layer 23 is used to fill most of the volume of the vacant area of ​​the hot melt adhesive layer 24 to reduce the flow of the adhesive in the hot melt adhesive layer 24 and ensure that the light-emitting chip 12 can be bound to the corresponding driving electrode 22 on the driving substrate 2.

[0091] In addition, when the expansion layer 23 has a light shielding property, the light shielding area of ​​the expansion layer 23 can be increased by expanding the volume of the expansion layer 23, thereby reducing or avoiding the possibility of laser irradiation to the driving electrode 22, the second substrate 21 and the light emitting chip 12, thereby reducing the damage caused by the laser to the components on the driving substrate 2 and the light emitting chip 12. When there are multiple light emitting chips 12 on the driving substrate 2, the volume expansion of the expansion layer 23 can also strengthen the shielding of light irradiated from one light emitting chip 12 to another adjacent light emitting chip 12, so as to reduce or avoid the problem of cross-color between adjacent light emitting chips 12.

[0092] like Figure 2 As shown, in the embodiment of the present disclosure, after the driving electrode 22 is disposed on the second substrate 21 , the expansion layer 23 may be disposed on the second substrate 21 , and the expansion layer 23 may be in contact with the second substrate 21 .

[0093] Among them, the side of the expansion layer 23 away from the second substrate 21 may not be lower than the side of the driving electrode 22 away from the second substrate 21, so as to ensure that after the display panel is formed, the expansion layer 23 with light shielding properties can effectively block the light irradiated from one light emitting chip 12 to another adjacent light emitting chip 12, reduce or avoid the possibility of cross-color between adjacent light emitting chips 12, and then improve the display effect of the display panel. However, it is not limited to this. In the present disclosure, the side of the expansion layer 23 away from the second substrate 21 may also be lower than the side of the driving electrode 22 away from the second substrate 21, but it is necessary to ensure that the expansion layer 23 can at least block part of the light irradiated from one light emitting chip 12 to another adjacent light emitting chip 12 after the volume expansion.

[0094] The side of the expansion layer 23 facing away from the second substrate 21 may be lower than the side of the hot melt adhesive facing away from the second substrate 21, so as to avoid the expansion layer 23 from expanding too much after the display panel is formed, and causing the expansion layer 23 to interfere with other structures in the display panel, thereby causing damage to the display panel. However, it is not limited to this. In the present disclosure, the side of the expansion layer 23 facing away from the second substrate 21 may be higher than the side of the hot melt adhesive facing away from the second substrate 21, or the side of the expansion layer 23 facing away from the second substrate 21 may also be flush with the side of the hot melt adhesive facing away from the second substrate 21, but it should be ensured that the expansion layer 23 will not interfere with other structures in the display panel after the volume expansion.

[0095] It should be noted that the expansion layer 23 in contact with the second substrate 21 in the embodiment of the present disclosure may be retained in the driving substrate 2 in the formed display panel.

[0096] In addition, if Figure 3 to Figure 4 As shown, in the embodiment of the present disclosure, the driving substrate 2 may further include a padding layer 25 , and the padding layer 25 is located on a side of the expansion layer 23 close to the second substrate 21 .

[0097] Specifically, after forming the driving electrode 22 , a padding layer 25 may be formed on the second substrate 21 , and then an expansion layer 23 may be formed on a side of the padding layer 25 away from the second substrate 21 , and the expansion layer 23 is connected to the padding layer 25 .

[0098] It should be noted that the padding layer 25 in the present disclosure may be made of insulating materials such as resin. The expansion layer 23 and the padding layer 25 on the second substrate 21 may be retained in the driving substrate 2 in the display panel.

[0099] After setting the cushioning layer 25, the side of the expansion layer 23 facing away from the second substrate 21 may not be lower than the side of the driving electrode 22 facing away from the second substrate 21, so as to ensure that after the display panel is formed, the expansion layer 23 with light-shielding properties can effectively block the light from one light-emitting chip 12 to another adjacent light-emitting chip 12, so as to reduce or avoid the possibility of cross-color between adjacent light-emitting chips 12, thereby improving the display effect of the display panel.

[0100] The embodiment of the present disclosure can reduce the amount of expansion of the expansion layer 23 in the direction away from the second substrate 21 by providing the cushioning layer 25, that is, by providing the cushioning layer 25, the deformation of the expansion layer 23 inside the hot melt adhesive layer 24 can be reduced, thereby reducing the possibility that the adhesive material in the hot melt adhesive layer 24 will flow violently due to excessive deformation of the expansion layer 23 in the hot melt adhesive layer 24, and then cause the position shift during the transfer of the light-emitting chip 12. Among them, the side of the cushioning layer 25 away from the second substrate 21 can be higher than the side of the driving electrode 22 away from the second substrate 21, or the side of the cushioning layer 25 away from the second substrate 21 can be flush with the side of the driving electrode 22 away from the second substrate 21, but it is not limited thereto, and the height of the cushioning layer 25 can be determined according to actual conditions.

[0101] At the same time, by setting the cushioning layer 25, the distance between the expansion layer 23 and the side of the hot melt adhesive layer 24 facing away from the second substrate 21 can also be reduced, so as to reduce or avoid the problem that the expanded part of the expansion layer 23 cannot completely fill the vacant area of ​​the hot melt adhesive layer 24 due to the small volume expansion of the expansion layer 23, thereby causing the light-emitting chip 12 to shift in position along with the adhesive material of the hot melt adhesive layer 24.

[0102] However, it is not limited to this. When the expansion layer 23 has a light-shielding property, the side of the expansion layer 23 facing away from the second substrate 21 may also be lower than the side of the driving electrode 22 facing away from the second substrate 21. However, it is necessary to ensure that the expansion layer 23 can at least block part of the light from one light-emitting chip 12 to another adjacent light-emitting chip 12 after the volume is expanded, so as to reduce the problem of cross-color between adjacent light-emitting chips 12.

[0103] After the cushioning layer 25 is provided, the side of the expansion layer 23 facing away from the second substrate 21 can be lower than the side of the hot melt adhesive facing away from the second substrate 21, so as to avoid the expansion layer 23 from expanding too much after the display panel is formed, and causing the expansion layer 23 to interfere with other structures in the display panel, thereby causing damage to the display panel. However, it is not limited to this. In the present disclosure, the side of the expansion layer 23 facing away from the second substrate 21 can be higher than the side of the hot melt adhesive facing away from the second substrate 21, or the side of the expansion layer 23 facing away from the second substrate 21 can also be flush with the side of the hot melt adhesive facing away from the second substrate 21, but it should be ensured that the expansion layer 23 will not interfere with other structures in the display panel after the volume expands.

[0104] Furthermore, the expansion layer 23 in the embodiment of the present disclosure may be made of an electrodeformable material, and the padding layer 25 may be made of a photoelectric material.

[0105] Specifically, the photoelectric material may include one or more of lead tin telluride, mercury cadmium telluride, triglycyl sulfate, and lithium tantalate. The electrodeformable material may include transparent materials such as elastomers containing azobenzene molecules, but is not limited to this. The photoelectric material and the electrodeformable material may also be other materials besides the aforementioned materials, which can be set according to actual conditions.

[0106] Under light, the cushioning layer 25 can convert light energy into electrical energy and transmit electrical signals to the expansion layer 23 . The expansion layer 23 expands in volume under the action of the electrical energy generated by the cushioning layer 25 .

[0107] For example, after the light emitting chip 12 is transferred to the driving substrate 2 and the display panel is formed, the padding layer 25 in the display panel can convert the light energy generated by the light emitting chip 12 into electrical energy when the light emitting chip 12 is working, and the expansion layer 23 expands in volume under the action of the electrical energy generated by the padding layer 25. That is, the expansion layer 23 in the display panel in the present disclosure can expand in volume when the light emitting chip 12 emits light, and when the expansion layer 23 has a light shielding property, the expansion layer 23 can block the light irradiated from one light emitting chip 12 to another adjacent light emitting chip 12, thereby reducing or avoiding the risk of cross-color between adjacent light emitting chips 12.

[0108] like Figures 8 to 11 As shown, in some embodiments of the present disclosure, the hot melt adhesive layer may include a first adhesive layer 241 and a second adhesive layer 242. At this time, the method for forming the driving substrate 2 may include: providing a second substrate 21, and forming a driving electrode 22 on the second substrate 21. After the driving electrode 22 is formed, firstly forming a first adhesive layer 241 on the second substrate 21, then forming an expansion layer 23 on a side of the first adhesive layer 241 away from the second substrate 21, and then forming a second adhesive layer 242 on a side of the expansion layer 23 away from the first adhesive layer 241.

[0109] It should be noted that when the hot melt adhesive layer 24 includes a first adhesive layer 241 and a second adhesive layer 242, the side of the expanded portion of the expansion layer 23 facing away from the second substrate 21 is flush with the side of the second adhesive layer 242 facing away from the second substrate 21, or the side of the expanded portion of the expansion layer 23 facing away from the second substrate 21 is higher than the side of the second adhesive layer 242 facing away from the second substrate 21, so as to ensure that the expansion layer 23 can completely fill the vacant area of ​​the hot melt adhesive layer 24 after the volume expands, so as to avoid positional displacement when the light-emitting chip 12 is transferred, thereby affecting the transfer accuracy and transfer yield of the light-emitting chip 12.

[0110] Among them, the first adhesive layer 241 in the embodiment of the present disclosure can cover the area of ​​the second substrate 21 except the driving electrode 22. The side of the first adhesive layer 241 away from the second substrate 21 can be flush with the side of the driving electrode 22 away from the second substrate 21. After the expansion layer 23 is formed, the side of the expansion layer 23 away from the second substrate 21 is not lower than the side of the driving electrode 22 away from the second substrate 21. When the expansion layer 23 has a light shielding property, the height of the expansion layer 23 increases after the volume expansion occurs, thereby reducing or avoiding the risk of damage to the light emitting chip 12, the driving electrode 22 and other components on the driving substrate 2 caused by the refraction and scattered light generated by the laser.

[0111] At the same time, the second adhesive layer 242 in the embodiment of the present disclosure can cover the driving electrode 22 and the expansion layer 23. The expansion layer 23 is located between the first adhesive layer 241 and the second adhesive layer 242, and the expansion layer 23 is in contact with the second adhesive layer 242. Therefore, when the hot melt adhesive layer 24 melts under specific light and forms a vacancy, the expansion layer 23 corresponding to the vacancy expands in volume under specific light to fill the vacancy, thereby reducing or avoiding the risk of positional displacement of the light-emitting chip 12 due to the flow of the adhesive in the hot melt adhesive layer 24.

[0112] For example, in the embodiment of the present disclosure, the vertical distance between the side of the second adhesive layer 242 facing away from the second substrate 21 and the side of the expansion layer 23 facing away from the second substrate 21 may be greater than 1 um, so that the second adhesive layer 242 completely covers the expansion layer 23 .

[0113] However, it is not limited to this. In the present disclosure, the side of the first adhesive layer 241 facing away from the second substrate 21 may also be higher than the side of the driving electrode 22 facing away from the second substrate 21, or the side of the first adhesive layer 241 facing away from the second substrate 21 may be slightly lower than the side of the driving electrode 22 facing away from the second substrate 21. However, it should be ensured that when the expansion layer 23 expands in volume, the side of the expanded part facing away from the second substrate 21 is higher than the side of the second adhesive layer 242 facing away from the second substrate 21, or is flush with the side of the second adhesive layer 242 facing away from the second substrate 21.

[0114] In order to reduce the manufacturing materials of the second adhesive layer 242, the present disclosure can preset the size of the volume expansion of the expansion layer 23, and set the second adhesive layer 242 of corresponding thickness according to the preset volume expansion size of the expansion layer 23, so that the side of the expanded part of the expansion layer 23 facing away from the second substrate 21 is flush with the side of the second adhesive layer 242 facing away from the second substrate 21, so as to reduce the manufacturing cost of the second adhesive layer 242.

[0115] like Figure 12 to Figure 14 As shown, in some other embodiments of the present disclosure, the method for forming the driving substrate 2 may further include: providing a second substrate 21, and forming a driving electrode 22 on the second substrate 21. Forming a hot melt adhesive layer 24 on the second substrate 21, the hot melt adhesive layer 24 covering the driving electrode 22 and the second substrate 21. After the hot melt adhesive layer 24 is formed, forming an expansion layer 23 on a side of the hot melt adhesive layer 24 away from the second substrate 21.

[0116] Among them, when the hot melt adhesive layer 24 melts under specific light and forms a void, the expansion layer 23 and the area corresponding to the void can also expand in volume under specific light, thereby filling the void, so as to reduce or avoid the flow of the adhesive material of the hot melt adhesive layer 24, and reduce or avoid the risk of positional displacement when the light-emitting chip 12 is transferred, thereby improving the transfer accuracy and transfer yield of the light-emitting chip 12.

[0117] When the expansion layer 23 has a light shielding property, the expansion layer 23 can also shield the laser irradiated to the side of the first substrate 11 away from the light emitting chip 12 during the transfer process of the light emitting chip 12, so as to reduce or avoid the possibility of the laser irradiating the hot melt adhesive layer 24 and causing the hot melt adhesive layer 24 to melt, thereby reducing or avoiding the problem of the light emitting chip 12 being displaced due to the flow of the adhesive material of the hot melt adhesive layer 24. At the same time, after the volume of the expansion layer 23 is expanded, the light shielding area can be increased to reduce or avoid the possibility of specific light irradiating the driving electrode 22, the light emitting chip 12, and the second substrate 21, thereby reducing or avoiding the risk of damage to the driving electrode 22, the light emitting chip 12 and other components on the second substrate 21.

[0118] like Figures 2 to 3 , Fig.11 as well as Figure 13 to Figure 14As shown, in the embodiment of the present disclosure, the expansion layer 23 may include a plurality of expansion structures, each expansion structure is arranged at intervals, and each expansion structure can expand in volume independently. A plurality of expansion structures can be arranged around the outer peripheral side of the driving electrode. When a plurality of light-emitting chips 12 are provided on the second substrate 21, at least two expansion structures are arranged between two adjacent light-emitting chips 12. In the embodiment of the present disclosure, the expansion structure can be formed by a spraying (ink-jet) process. By arranging a plurality of expansion structures at intervals, the present disclosure can avoid the problem that the area corresponding to the vacancy of the hot melt adhesive layer 24 in the expansion layer 23 caused by the connection of the expansion structures will stretch and expand the adhesive material in the surrounding area when the expansion occurs, thereby causing the hot melt adhesive layer 24 to have different thicknesses and causing the light-emitting chip 12 to be offset.

[0119] In the process of aligning the transfer substrate 1 and the drive substrate 2, the light emitting chip 12 is aligned with the drive electrode 22 on the second substrate 21, and the light emitting chip 12 is bonded to the hot melt adhesive layer 24 covering the side of the drive electrode 22 facing away from the second substrate 21. By providing the hot melt adhesive layer 24, the position of the light emitting chip 12 on the drive substrate 2 can be fixed to avoid displacement during the transfer process. In addition, the hot melt adhesive layer 24 can also achieve buffering when the drive substrate 2 and the transfer substrate 1 are aligned, reducing or avoiding the collision between the light emitting chip 12 and the drive electrode 22 during alignment, and causing the risk of damage to the light emitting chip 12 and the drive electrode 22.

[0120] After the light emitting chip 12 is peeled off from the first substrate 11 , the hot melt adhesive layer 24 is melted to remove the hot melt adhesive layer 24 from the second substrate 21 , and the light emitting chip 12 is bound to the driving electrode 22 .

[0121] When a hot melt adhesive layer 24 is disposed between the second substrate 21 and the side of the expansion layer 23 close to the second substrate 21 , the expansion layer 23 and the hot melt adhesive layer 24 can be removed from the second substrate 21 together.

[0122] like Figures 2 to 4 as well as Figures 15 to 17 As shown, the present disclosure provides a driving substrate 2, which includes a second substrate 21, a driving electrode 22 and an expansion layer 23. The expansion layer 23 and the driving electrode 22 are located on the same side of the second substrate 21, the expansion layer 23 is arranged on the outer peripheral side of the driving electrode 22, and the expansion layer 23 can expand in volume under specific light. The driving substrate 2 may include one driving electrode 22, but is not limited thereto. The driving substrate 2 may also include multiple driving electrodes 22, and the multiple driving electrodes 22 may be arranged in an array with intervals.

[0123] Furthermore, the driving substrate 2 may also include a hot melt adhesive layer 24, which at least covers the driving electrode 22, so that when the light-emitting chip 12 is transferred to the driving substrate 2, the light-emitting chip 12 can be bonded to the hot melt adhesive layer 24 through the hot melt adhesive layer 24 to achieve position fixation, thereby reducing or avoiding the problem of position displacement when the light-emitting chip 12 is bound to the corresponding driving electrode 22 on the second substrate 21.

[0124] In the disclosed embodiment, the hot melt adhesive layer 24 can be melted under specific light, the hot melt adhesive layer 24 is in contact with the expansion layer 23, and the orthographic projection of the hot melt adhesive layer 24 on the second substrate 21 covers the orthographic projection of the expansion layer 23 on the second substrate 21. By causing the expansion layer 23 to expand in volume, the problem of positional displacement of the light emitting chip 12 during transfer caused by the melting of the hot melt adhesive layer 24 on the driving substrate 2 can be reduced or avoided, thereby improving the transfer accuracy and transfer yield of the light emitting chip 12.

[0125] It should be noted that the driving substrate 2 provided in the embodiments of the present disclosure can be used in any of the above-mentioned chip transfer methods.

[0126] The present disclosure further provides a display panel, which includes a plurality of light-emitting chips 12 arranged in an array and spaced apart from each other, and any one of the driving substrates 2 described above, wherein the light-emitting chip 12 is correspondingly bound to a side of the driving electrode 22 away from the second substrate 21 .

[0127] The expansion layer 23 in the display panel may have a light shielding property, and the side of the expansion layer 23 facing away from the second substrate 21 may be no lower than the side of the driving electrode 22 facing away from the second substrate 21. When the display panel is working, the expansion layer 23 may expand in volume under the action of the emitted light of the light emitting chip 12 to block the light from one adjacent light emitting chip 12 to irradiate another adjacent light emitting chip 12, thereby reducing or avoiding the possibility of cross-color between the light emitting chips 12 and improving the display effect of the display panel.

[0128] When the hot melt adhesive layer 24 is not needed in the display panel, the hot melt adhesive layer 24 on the driving substrate 2 can be removed during the transfer process of the light emitting chip 12 .

[0129] In the description of the present disclosure, “plurality” means two or more than two, unless otherwise clearly and specifically defined.

[0130] It should be noted that "upper", "lower", "left", "right" and the like are only used for distinction to facilitate description, and do not impose any directional limitation on the embodiments of the present invention. For example, the "upper" may actually be "lower", "left", "right" and other directions. In the present disclosure, unless otherwise clearly specified and limited, the terms "assembly", "connection" and the like should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral whole; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium; it may be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to the specific circumstances.

[0131] In the description of this specification, the description with reference to the terms "some embodiments", "exemplarily", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0132] Although the embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and cannot be construed as limitations on the present disclosure. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present disclosure. Therefore, any changes or modifications made in accordance with the claims and specification of the present disclosure shall fall within the scope covered by the patent of the present disclosure.

Claims

1. A chip transfer method, characterized in that: The chip transfer method comprises: Providing a transfer substrate, the transfer substrate comprising a first substrate and a light-emitting chip on the first substrate; A driving substrate is provided, the driving substrate comprising a second substrate and a driving electrode, an expansion layer and a hot melt adhesive layer located on the same side of the second substrate; the expansion layer is arranged on at least one side of the driving electrode, and the expansion layer can expand in volume under specific light; the hot melt adhesive layer is in contact with the expansion layer, and the hot melt adhesive layer can melt under the specific light; the hot melt adhesive layer at least covers the driving electrode, and the orthographic projection of the hot melt adhesive layer on the second substrate covers the orthographic projection of the expansion layer on the second substrate; Aligning the transfer substrate and the drive substrate so that the light-emitting chip is correspondingly bound to the drive electrode through the hot-melt adhesive layer; A specific light irradiation technique is used to irradiate a side of the first substrate away from the light emitting chip, so as to separate the first substrate from the light emitting chip.

2. The chip transfer method according to claim 1, characterized in that: The method for forming the driving substrate includes: Providing a second substrate; forming the driving electrode on the second substrate; forming the expansion layer on the second substrate; forming the hot melt adhesive layer on the second substrate, wherein the hot melt adhesive layer covers the driving electrode and the expansion layer; Wherein, if the hot melt adhesive layer melts under the specific light and forms a vacancy, the expansion layer corresponding to the vacancy can expand in volume under the specific light to fill the vacancy.

3. The chip transfer method according to claim 2, characterized in that: After forming the driving electrode and before forming the expansion layer, the chip transfer method further includes: forming a cushioning layer on the second substrate, wherein the cushioning layer is located on a side of the expansion layer close to the second substrate, so that a side of the expansion layer facing away from the second substrate is not lower than a side of the driving electrode facing away from the second substrate.

4. The chip transfer method according to claim 3, characterized in that: The expansion layer is made of an electrodeformable material, and the cushioning layer is made of a photoelectric material. The cushioning layer can convert light energy into electrical energy, and the expansion layer can expand in volume under the action of the electrical energy generated by the cushioning layer.

5. The chip transfer method according to claim 1, characterized in that: The hot melt adhesive layer includes a first adhesive layer and a second adhesive layer; and the method for forming the driving substrate includes: Providing a second substrate; forming the driving electrode on the second substrate; forming the first adhesive layer on the second substrate; forming the expansion layer on a side of the first adhesive layer facing away from the second substrate; forming a second adhesive layer on a side of the expansion layer away from the first adhesive layer, wherein the second adhesive layer at least covers the expansion layer; Wherein, if the hot melt adhesive layer melts under the specific light and forms a vacancy, the expansion layer corresponding to the vacancy can expand in volume under the specific light to fill the vacancy.

6. The chip transfer method according to claim 1, characterized in that: The method for forming the driving substrate includes: Providing a second substrate; forming the driving electrode on the second substrate; forming the hot melt adhesive layer on the second substrate, wherein the hot melt adhesive layer covers the driving electrode and the second substrate; The expansion layer is formed on a side of the hot melt adhesive layer facing away from the second substrate.

7. The chip transfer method according to claim 1, characterized in that: The expansion layer includes a plurality of expansion structures, each of the expansion structures is arranged at intervals, and the plurality of expansion structures are arranged around the outer circumference of the driving electrode.

8. A driving substrate, characterized in that: include: a second substrate; A driving electrode, located on the second substrate; The expansion layer is located on the same side of the second substrate as the driving electrode, and the expansion layer is arranged on at least one side of the driving electrode; the expansion layer can expand in volume under specific light.

9. The driving substrate according to claim 8, characterized in that: The driving substrate includes a hot melt adhesive layer that can melt under the specific light, the hot melt adhesive layer is in contact with the expansion layer, the hot melt adhesive layer at least covers the driving electrode, and the orthographic projection of the hot melt adhesive layer on the second substrate covers the orthographic projection of the expansion layer on the second substrate.

10. A display panel, characterized in that: It comprises a plurality of light emitting chips arranged in an array and spaced apart from each other and a driving substrate as claimed in any one of claims 8 or 9, wherein the light emitting chip is correspondingly bound to a side of the driving electrode facing away from the second substrate.

11. The display panel according to claim 10, characterized in that: The expansion layer has a light-shielding property, and the side of the expansion layer facing away from the second substrate is not lower than the side of the driving electrode facing away from the second substrate; when the light-emitting chip emits light, the expansion layer can expand in volume to block the light from one light-emitting chip to another adjacent light-emitting chip.

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