A chip detection board, a chip transfer method, a display backplane, and a display device

Abstract

The present invention relates to a chip detection board, a chip transfer method, a display backplane and a display device. The chip detection board includes a substrate main body; a first conductive layer provided on one side of the substrate main body, the first conductive layer including a first height region and a second height region, the first height region being relatively close to the substrate main body and the second height region being relatively far from the substrate main body; a piezoelectric material layer provided on a part of the region of the first conductive layer; and a second conductive layer provided at least on the side of the piezoelectric material layer away from the substrate main body, the second conductive layer being electrically connected to the second side of the piezoelectric material layer, the second side being the side opposite to the first side. By applying pressure to the piezoelectric material layer, electrical energy can be generated to drive the light-emitting chip, and then the light-emitting condition of the light-emitting chip can be detected. It is not necessary to wait until the light-emitting backplane is manufactured and powered on for detection. In some implementation processes, it is beneficial to timely detect the defective pixels on the light-emitting backplane and is also beneficial to subsequent maintenance.

Description

Technical Field

[0001] The present invention relates to the field of light-emitting chip manufacturing, and particularly to a chip detection board, a chip transfer method, a display backplane, and a display device. Background Art

[0002] Micro LED (Micro Light Emitting Diode) displays have advantages in good stability, long lifespan, and operating temperature. At the same time, they inherit the advantages of LEDs (Light Emitting Diodes) such as low power consumption, high color saturation, fast response speed, and strong contrast, and have great application prospects.

[0003] In the manufacturing process of display devices including but not limited to Micro LED (Micro Light Emitting Diode) displays, light-emitting chips such as Micro LED chips need to be transferred onto the display panel. However, when any light-emitting chip is damaged or has poor contact, etc., it will cause bad pixels on the display panel, affecting imaging. However, the defective light-emitting chips can only be inspected by power-on after the light-emitting chips are bonded, resulting in a complex process for repair and replacement.

[0004] Therefore, how to simplify the detection of defective light-emitting chips is an urgent problem to be solved. Summary of the Invention

[0005] In view of the deficiencies of the above-mentioned related technologies, the purpose of the present application is to provide a chip detection board, a chip transfer method, a display backplane, and a display device, aiming to solve the problem that the defective light-emitting chips can only be inspected by power-on after the light-emitting chips are bonded, resulting in a complex process for repair and replacement.

[0006] A chip detection board includes:

[0007] A substrate body;

[0008] A first conductive layer provided on one side of the substrate body, the first conductive layer including a first height region and a second height region, the first height region being relatively close to the substrate body, and the second height region being relatively far from the substrate body;

[0009] A piezoelectric material layer provided on a part of the region of the first conductive layer, the piezoelectric material layer being provided on the side of the first conductive layer away from the substrate body, a first side of the piezoelectric material layer being electrically connected to the first height region of the first conductive layer, and when the piezoelectric material layer deforms in a direction perpendicular to the substrate body, a voltage is generated between the first side and a second side, the second side being the side opposite to the first side;

[0010] A second conductive layer, the second conductive layer is disposed at least on a side of the piezoelectric material layer away from the substrate body, and the second conductive layer is electrically connected to a second side of the piezoelectric material layer.

[0011] Through the piezoelectric material layer and the first and second conductive layers cooperating therewith, the above chip detection board can generate electric energy by applying pressure to the piezoelectric material layer to drive the light-emitting chip, and then detect the light-emitting condition of the light-emitting chip; in some implementation processes, even when the light-emitting backplane is not completely fabricated, only by applying pressure, the light-emitting chips arranged on the light-emitting backplane can be temporarily driven and lit for detection purposes, without waiting for the light-emitting backplane to be fabricated and then powered on for detection, which is beneficial to timely discovering defective points on the light-emitting backplane and also beneficial to subsequent maintenance.

[0012] Based on the same inventive concept, the present application also provides a chip transfer method, including:

[0013] Providing a chip detection board, the chip detection board being the chip detection board as described above;

[0014] Providing a light-emitting backplane, the light-emitting backplane including a third conductive layer and a fourth conductive layer disposed on a first surface and a fifth conductive layer and a sixth conductive layer disposed on a second surface, the third conductive layer and the fourth conductive layer corresponding to electrodes of the light-emitting chips to be transferred for electrically connecting with the electrodes of the light-emitting chips, the fifth conductive layer being electrically connected to the third conductive layer, and the sixth conductive layer being electrically connected to the fourth conductive layer;

[0015] Placing the light-emitting backplane on the chip detection board, the fifth conductive layer being electrically connected to the second height region of the first conductive layer, and the sixth conductive layer being electrically connected to the second conductive layer;

[0016] Transferring the light-emitting chip to the light-emitting backplane, and before the bonding material of the light-emitting chip completely solidifies, applying pressure to the light-emitting backplane sufficient to cause the piezoelectric material layer to generate a current sufficient to drive the light-emitting chip to operate.

[0017] The above chip transfer method can realize power supply and drive of the light-emitting chip during the process of transferring the light-emitting chip by using the above chip detection board and adopting a light-emitting backplane that can directly form a conductive path for the light-emitting chip in cooperation with the chip detection board, detect the defective point condition of the light-emitting chips arranged on the light-emitting backplane during the process of transferring the light-emitting chip, is convenient for timely replacement and maintenance in some implementation processes, and can perform maintenance before the bonding material of the light-emitting chip completely solidifies, avoiding the step of debonding and reducing the complexity and difficulty of maintenance.

[0018] Optionally, a plurality of the piezoelectric material layers are included on the chip detection board, and the piezoelectric material layers are arranged in an array. The distance between every two adjacent piezoelectric material layers and between every two adjacent second height regions in the connection direction of the two electrodes of the light-emitting chip is equal to the distance between every three adjacent light-emitting chips in the connection direction of the two electrodes;

[0019] Before transferring the light-emitting chip to the light-emitting backplane, it includes:

[0020] Transfer the light-emitting chip to a transfer substrate, and arrange the positions of the positive and negative electrodes of every two adjacent light-emitting chips in the connection direction of the two electrodes of the light-emitting chip in an inverted manner.

[0021] By alternately arranging the electrode sequences of the light-emitting chips, a second conductive layer, a second height region of the first conductive layer, a fifth conductive layer, and a sixth conductive layer at one place can be shared by two light-emitting chips, and at least one of the piezoelectric material layer, the second conductive layer, the second height region of the first conductive layer, the fifth conductive layer, and the sixth conductive layer can be formed into a larger size. In some implementation processes, the total number of various structures required on the chip detection board is reduced, making the manufacturing difficulty and the requirement for precision of the chip detection board lower, which is beneficial to the yield rate and cost control.

[0022] Based on the same inventive concept, the present application also provides a display backplane, including:

[0023] A light-emitting chip;

[0024] It further includes a third conductive layer and a fourth conductive layer provided on the first surface and a fifth conductive layer and a sixth conductive layer provided on the second surface. The third conductive layer and the fourth conductive layer are electrically connected to the electrodes of the light-emitting chip, the fifth conductive layer is electrically connected to the third conductive layer, and the sixth conductive layer is electrically connected to the fourth conductive layer;

[0025] The light-emitting chip is transferred to the display backplane by the chip transfer method as described above.

[0026] The above display backplane can detect defective pixels and perform repairs during the process of transferring the chips. The display backplane has a high yield rate and good quality.

[0027] Based on the same inventive concept, the present application also provides a display device, including a frame and a display backplane, the display backplane is fixed on the frame, and the display backplane is the display backplane as described above.

[0028] The above display device has a high yield rate and good quality. Description of the Drawings

[0029] Figure 1Schematic diagram of the structure of the chip detection board provided by the embodiment of the present invention Figure 1 ;

[0030] Figure 2 Schematic diagram of the structure of the chip detection board provided by the embodiment of the present invention Figure 2 ;

[0031] Figure 3 Schematic diagram of the structure of the chip detection board provided by the embodiment of the present invention Figure 3 ;

[0032] Figure 4 Schematic diagram of the structure of the chip detection board provided by the embodiment of the present invention Figure 4 ;

[0033] Figure 5 Schematic diagram of the structure of the chip detection board provided by the embodiment of the present invention Figure 5 ;

[0034] Figure 6 Schematic diagram of the basic process of the chip transfer method provided by another alternative embodiment of the present invention;

[0035] Figure 7 Schematic diagram of the structure of the light-emitting backplane provided by another alternative embodiment of the present invention;

[0036] Figure 8 Schematic diagram of the light-emitting backplane provided on the chip detection board according to another alternative embodiment of the present invention;

[0037] Figure 9 Schematic diagram of the transfer of the light-emitting chip to the light-emitting backplane provided by another alternative embodiment of the present invention;

[0038] Figure 10 Schematic diagram of the cooperation between the chip detection board and the light-emitting backplane provided by another alternative embodiment of the present invention;

[0039] Figure 11 Arrangement diagram of the light-emitting chips provided by another alternative embodiment of the present invention Figure 1 ;

[0040] Figure 12 For corresponding Figure 11 Top view schematic diagram of the chip detection board;

[0041] Figure 13 Arrangement diagram of the light-emitting chips provided by another alternative embodiment of the present invention Figure 2 ;

[0042] Figure 14 For corresponding Figure 13 Top view schematic diagram of the chip detection board;

[0043] Figure 15Schematic diagram of the refinement process of some steps of the chip transfer method provided by another alternative embodiment of the present invention;

[0044] Figure 16 Schematic diagram of a light-transmitting substrate provided with a light-emitting chip according to another alternative embodiment of the present invention;

[0045] Figure 17 Schematic diagram of the transfer of a light-emitting chip to a light-emitting backplane according to another alternative embodiment of the present invention;

[0046] Figure 18 Schematic diagram of the process of some steps of the chip transfer method provided by another alternative embodiment of the present invention;

[0047] Explanation of reference numerals:

[0048] 1 - Substrate main body; 21 - First conductive layer; 211 - First height region; 212 - Second height region; 213 - Transition region; 214 - Spacer; 22 - Piezoelectric material layer; 221 - Electrode layer provided on the first side of the piezoelectric material layer; 222 - Electrode layer provided on the second side of the piezoelectric material layer; 23 - Second conductive layer; 3 - Light-emitting backplane; 31 - Third conductive layer; 32 - Fourth conductive layer; 33 - Fifth conductive layer; 34 - Sixth conductive layer; 35 - Conductive via; 4 - Light-emitting chip; 401 - First light-emitting chip; 402 - Second light-emitting chip; 403 - Third light-emitting chip; 41 - Positive electrode; 42 - Negative electrode; 43 - Bonding material; 5 - Light-transmitting substrate; d1 - Distance between every two adjacent piezoelectric material layers in the connection direction of the two electrodes of the light-emitting chip; d2 - Distance between every three adjacent light-emitting chips in the connection direction of the two electrodes; F - Pressure; L - Connection direction of the electrodes. Detailed implementation manners

[0049] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used in the description of the present application herein are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0051] In the related art, the defective pixel detection of a light-emitting chip needs to be carried out by energizing a light-emitting backplane after the light-emitting chip is bonded, resulting in a complex replacement and repair process. Based on this, the present application hopes to provide a solution that can solve the above technical problems, and its detailed content will be described in the following embodiments.

[0052] Embodiment:

[0053] This embodiment provides a chip detection board, as Figure 1 shown. The chip detection board includes a substrate main body 1, a first conductive layer 21, a piezoelectric material layer 22, and a second conductive layer 23. The first conductive layer 21 is disposed on one side of the substrate main body 1. The first conductive layer 21 includes a first height region 211 and a second height region 212. The first height region 211 is relatively close to the substrate main body 1, and the second height region 212 is relatively far from the substrate main body 1. The piezoelectric material layer 22 is disposed on a part of the region of the first conductive layer 21. The piezoelectric material layer 22 is disposed on the side of the first conductive layer 21 away from the substrate main body 1. The first side of the piezoelectric material layer 22 is electrically connected to the first height region 211 of the first conductive layer 21. When the piezoelectric material layer 22 deforms in the direction perpendicular to the substrate main body 1, a voltage is generated between the first side and the second side. The second conductive layer 23 is disposed on the side of the piezoelectric material layer 22 away from the substrate main body 1. The second conductive layer 23 is electrically connected to the second side of the piezoelectric material layer 22, and the second side is the side opposite to the first side.

[0054] The first conductive layer and the second conductive layer include, but are not limited to, conductive lines or conductive structures formed of various conductive materials, and may be conductive metals. For example, in one example, the material of the first conductive layer and / or the second conductive layer may include, but is not limited to, at least one of Cr, Ni, Al, Ti, Au, Pt, W, Pb, Rh, Sn, Cu, and Ag.

[0055] The piezoelectric material layer includes a crystal material that generates a voltage on both end faces when subjected to pressure. The two end faces of the piezoelectric material layer in this embodiment are arranged along the thickness direction of the substrate main body, that is, the deformation direction in which the piezoelectric material layer generates the piezoelectric effect is perpendicular to the plane where the substrate main body is located. The two end faces of the piezoelectric material layer in this embodiment are respectively the above-mentioned first side and second side.

[0056] The first conductive layer and the second conductive layer are respectively electrically connected to the first side and the second side of the piezoelectric material layer. When the piezoelectric material layer generates a voltage, the first conductive layer and the second conductive layer also have corresponding voltages. It can be understood that if the first conductive layer and the second conductive layer are connected, a corresponding current will be generated due to this voltage.

[0057] In the chip detection board of this embodiment, the first conductive layer and the second conductive layer can be respectively used to form electrical connections with the two electrodes of the light-emitting chip. Of course, the electrical connections referred to in this embodiment include electrical connections with direct contact and also include electrical connections achieved through other conductive paths. After the first conductive layer and the second conductive layer form electrical connections with the light-emitting chip, a circuit is formed. By applying pressure to the piezoelectric material layer, a current can be formed to drive the light-emitting chip to work, that is, emit light. It can be understood that in practical applications, the correspondence between the two electrodes of the light-emitting chip and the first conductive layer and the second conductive layer is determined by the direction of the voltage formed by the positive and negative electrodes and the piezoelectric material layer. That is, the positive electrode of the light-emitting chip will be electrically connected to the conductive layer with a higher voltage after the piezoelectric material layer is pressed, and the negative electrode will be electrically connected to the conductive layer with a lower voltage.

[0058] For the chip detection board of this embodiment, by electrically connecting the two electrodes of the light-emitting chip to the first conductive layer and the second conductive layer respectively and applying pressure to the piezoelectric material layer, the piezoelectric material layer generates a voltage to form a current to drive the light-emitting chip to work, so as to verify whether the light-emitting chip is damaged. At the same time, when the light-emitting chip is disposed on the light-emitting backplane, it can also verify whether the light-emitting chip is damaged or whether the electrical connection between the light-emitting chip and the light-emitting backplane is normal.

[0059] Exemplarily, usually the heights of the two electrodes of the light-emitting chip are basically the same or the light-emitting chip is disposed on the light-emitting backplane, and the light-emitting backplane is flat. In order to make the electrodes of the light-emitting chip or the corresponding conductive regions of the light-emitting backplane form better contact with the first conductive layer and the second conductive layer of the chip detection board, the second height region of the first conductive layer and the second conductive layer can be in the same plane; that is, from Figure 1 the example perspective, the second height region 212 and the second conductive layer 23 are at the same height.

[0060] In some embodiments, the second height region of the first conductive layer includes any one of the following:

[0061] A spacer is provided between the first conductive layer and the substrate body, and the second height region is formed at the spacer of the first conductive layer;

[0062] The first conductive layer includes a conductive plane with equal thickness and a conductor disposed on a partial region on the side of the conductive plane away from the substrate body, and the second height region is formed at the conductor.

[0063] For example, the foregoing Figure 1In the example, the chip detection board further includes a spacer 214, which can be insulating but can also be conductive. The spacer 214 raises the first conductive layer 21 to form a second height region 212. The thickness of the spacer 214 can be equivalent to the sum of the thicknesses of the piezoelectric material layer 22 and the first height region 211, such that the second height region 212 and the second conductive layer 23 are in the same plane. The first conductive layer 21 can be a flexible conductive layer, or at least the part between the piezoelectric material layer 22 and the spacer 214 is a flexible conductive layer, and this part of the flexible conductive layer forms a transition region 213 from the first height region 211 to the second height region 212 of the first conductive layer 21.

[0064] As other examples, please refer to Figure 2 , the chip detection board further includes a spacer 214, which raises the first conductive layer 21 to form a second height region 212. In this example, the first conductive layer 21 can be a non-flexible conductive layer. The first conductive layer 21 is laid on the surface of the substrate body 1 from the piezoelectric material layer 22 to the spacer 214, and is arranged along the side wall of the spacer 214 to the surface of the spacer 214 away from the substrate body 1. The first conductive layer 21 can be a metal sheet or a metal conductive layer formed by depositing conductive metal on the surfaces of the substrate body 1 and the spacer 214, etc. In this example, the first conductive layer 21 can be arranged relying on the side wall of the spacer 214, and there is no need to form a flexible transition region 213 between the first height region 211 and the second height region 212.

[0065] As Figure 3 shown in the example, the overall form of the first conductive layer 21 is similar to the implementation method of the previous example, but the first conductive layer 21 can also be composed of two parts provided on the substrate body 1 and the spacer 214. One part of the first conductive layer 21 is laid on one side surface of the substrate body 1, and the other part of the first conductive layer 21 is provided on the surface of the spacer 214. When the spacer 214 is arranged on the substrate body 1, the respective parts of the first conductive layer 21 on the substrate body 1 and the spacer 214 are connected to form a complete first conductive layer 21.

[0066] As Figure 4 shown in the example, the first conductive layer 21 can further include an equipotential conductive plane, which is laid on the substrate body 1. The conductive plane includes but is not limited to forms such as metal sheets and metal deposition layers. A conductive spacer 214 is arranged on the conductive plane, and this conductive spacer 214 serves as the second height region 212 of the first conductive layer 21.

[0067] The spacer blocks in the above examples can be provided in forms including but not limited to bonding, welding, etc. In some other embodiments, the spacer blocks can also be integrally formed with the substrate body, that is, a raised structure capable of raising the first conductive layer is directly formed on the substrate body. The implementation manner of the second height region in this embodiment is not limited to the above forms and can also be any other manner.

[0068] To better ensure the contact between the electrodes of the light-emitting chip and the first conductive layer and the second conductive layer, the first conductive layer and / or the second conductive layer can be made of a material with certain elasticity or ductility. Of course, it is also possible to design that the spacer blocks or conductors, etc. of the second height region for supporting the first conductive layer have certain elasticity. When the piezoelectric material layer is pressed, it will produce a certain deformation. Of course, the degree of deformation has a certain relationship with the specific piezoelectric material in the piezoelectric material layer. The piezoelectric material layer in this embodiment can use at least one of piezoelectric crystal materials, piezoelectric ceramic materials, and piezoelectric polymers, including but not limited to. By endowing a certain elasticity to the electrical connection structure (the first conductive layer and / or the second conductive layer) or the structure (spacer blocks or conductors) supporting the electrical connection structure, when the piezoelectric material layer is deformed under pressure, the electrodes of the light-emitting chip can also maintain a good electrical connection relationship with the first conductive layer and the second conductive layer. And in some examples, the first conductive layer has a certain elasticity in the second height region, which can make the second height region slightly higher than the second conductive layer, ensuring that when the second conductive layer forms an electrical connection with the corresponding electrode of the chip, the first conductive layer can form a better contact with the corresponding conductive region to form an electrical connection with the corresponding electrode of the chip. For example, the distance between the second height region and the surface of the substrate body is 0.5 micrometers, 1 micrometer, etc. larger than the distance between the second conductive layer and the surface of the substrate body, and the actual height difference can be determined according to the actual deformation amount.

[0069] It can be understood that if the end faces of the two electrodes of the light-emitting chip to be detected, or the conductive regions connecting the two electrodes of the light-emitting chip on the light-emitting backplane are not in the same plane, then the second height region of the first conductive layer of the chip detection board can be designed not to be in the same plane as the second conductive layer. The positions of the second height region of the first conductive layer and the second conductive layer are determined according to the actual structural conditions of the light-emitting chip or the light-emitting backplane.

[0070] The piezoelectric material layer can include electrode layers respectively provided on two end faces and the piezoelectric material sandwiched between the two electrode layers. In practical applications, the electrode layers of the piezoelectric material layer can be used as part of the first conductive layer and / or the second conductive layer. Exemplarily, as Figure 1 in the example, the electrode layer provided on the first side of the piezoelectric material layer is connected to a flexible conductive sheet to jointly form the first conductive layer, and the electrode layer provided on the second side of the piezoelectric material layer directly serves as the second conductive layer of the chip detection board. Of course, it is also feasible to continue to provide other conductive structures such as conductive sheets on the electrode layer on the second side of the piezoelectric material layer.

[0071] In practical applications, the second height region of the first conductive layer is set at a position corresponding to the electrical connection region of the light-emitting chip or the light-emitting backplane to be detected. In this embodiment, the sizes and positions of the second conductive layer and the second height region respectively correspond to the positive and negative electrodes on a light-emitting chip, that is, the sizes of the second conductive layer and the second height region and the interval between the second conductive layer and the second height region can be the same as or substantially the same as the sizes of the positive and negative electrodes on the light-emitting chip and the interval between the positive and negative electrodes on the light-emitting chip.

[0072] It should also be noted that only one minimum unit for detecting one light-emitting chip is exemplified in the above example. In practical applications, there can be multiple piezoelectric material layers on the chip detection board. Correspondingly, there are also multiple second height regions of the first conductive layer. The chip detection board can detect multiple light-emitting chips. The multiple piezoelectric material layers are arranged in an array. The number of the first conductive layers on the chip detection board can be the same as the number of the piezoelectric material layers. For example Figures 1 to 4 in the example of, each piezoelectric material layer 22 respectively corresponds to a first conductive layer 21, and each first conductive layer 21 is used for electrically connecting with a single light-emitting chip. In some other embodiments, there are multiple piezoelectric material layers on the chip detection board, and the piezoelectric material layers are arranged in an array, and each first conductive layer communicates with multiple piezoelectric material layers. Exemplarily, as Figure 5 shown, the first conductive layer 21 can be a flexible conductive layer. In the illustrated direction, the piezoelectric material layers 22 and the pads 214 are alternately arranged, and the first conductive layer 21 is an integral body and communicates with all the piezoelectric material layers 22.

[0073] The chip detection board of this embodiment, through the piezoelectric material layer and the first conductive layer and the second conductive layer cooperating therewith, can generate electric energy by applying pressure to the piezoelectric material layer to drive the light-emitting chip, and then detect the light-emitting condition of the light-emitting chip; in some implementation processes, even when the light-emitting backplane is not completely manufactured, only by applying pressure, the light-emitting chips arranged on the light-emitting backplane can be temporarily driven and lit for detection purposes, without waiting until the light-emitting backplane is manufactured and then powered on for detection, which is beneficial to timely discovering the defective points on the light-emitting backplane and is also beneficial to subsequent maintenance.

[0074] Another alternative embodiment of the present invention:

[0075] Based on the above chip detection board, this embodiment provides a chip transfer method, and the chip transfer method exemplifies a process of using the above chip detection board for chip detection. As Figure 6 shown, the chip transfer method of this embodiment includes:

[0076] S101. Provide a chip detection board;

[0077] This chip detection board is the chip detection board exemplified in the above embodiment.

[0078] S102. Provide a light-emitting backplane;

[0079] It should be noted that as Figure 7 shown (for ease of understanding, Figure 7 the light-emitting chip 4 is also shown in the figure, but the light-emitting chip 4 is not provided in step S102), the light-emitting backplane 3 of this embodiment includes a third conductive layer 31 and a fourth conductive layer 32 provided on the first surface and a fifth conductive layer 33 and a sixth conductive layer 34 provided on the second surface. The third conductive layer 31 and the fourth conductive layer 32 correspond to the electrodes of the light-emitting chip 4 to be transferred and are used for electrically connecting with the electrodes of the light-emitting chip 4. The fifth conductive layer 33 is electrically connected to the third conductive layer 31, and the sixth conductive layer 34 is electrically connected to the fourth conductive layer 32. In practical applications, the above-mentioned third conductive layer 31, fourth conductive layer 32, fifth conductive layer 33, and sixth conductive layer 34 may be in the form of contact electrodes or contact pads.

[0080] Exemplarily, a plurality of conductive vias 35 are formed on the light-emitting backplane 3 that penetrate the light-emitting backplane 3 in a direction perpendicular to the light-emitting backplane 3 (or can be understood as the thickness direction). The connection between the third conductive layer 31 and the fifth conductive layer 33 is realized through the conductive vias 35. Similarly, the connection between the fourth conductive layer 32 and the sixth conductive layer 34 is realized through the conductive vias 35.

[0081] S103. Place the light-emitting backplane on the chip detection board;

[0082] As Figure 8 shown, the fifth conductive layer 33 is electrically connected to the second height region 212 of the first conductive layer 21, and the sixth conductive layer 34 is electrically connected to the second conductive layer 23. Exemplarily, the connection between the light-emitting backplane and the chip detection board may be a releasable adhesive connection and is realized through a conductive adhesive material, or the light-emitting backplane may not be fixed to the chip detection board, that is, it is directly placed on the chip detection board.

[0083] S104. Transfer the light-emitting chip to the light-emitting backplane. Before the bonding material of the light-emitting chip completely solidifies, apply a pressure to the light-emitting backplane sufficient to generate a current sufficient to drive the light-emitting chip to work in the piezoelectric material layer;

[0084] The light-emitting chips of this embodiment include, but are not limited to, various LED chips such as Micro LED chips and Mini LED (Mini Light Emitting Diode) chips. The light-emitting chips of this embodiment are in a flip-chip structure. For example, in one example, the Micro LED chip is a flip-chip Micro LED chip, and in another example, the Mini LED chip is in a flip-chip structure. AsFigure 9 As shown, after the light-emitting chip 4 is disposed on the light-emitting backplane 3, the two electrodes of the light-emitting chip 4 are respectively connected to the third conductive layer 31 and the fourth conductive layer 32 on the light-emitting backplane 3. At this time, a loop is formed between the positive and negative electrodes of the light-emitting chip 4. When the piezoelectric material layer 22 generates a voltage, a current is formed in the loop, and the current drives the light-emitting chip 4 to work. It should be noted that the operation of the light-emitting chip 4 in this embodiment is not limited to the light-emitting chip 4 reaching the rated operating state. In some implementation processes, if it is only necessary to detect whether the light-emitting chip 4 can emit light, it is only necessary to drive the light-emitting chip 4 to generate light. At this time, the generated current can be lower than the rated current of the light-emitting chip 4.

[0085] The chip transfer method of this embodiment can detect whether the light-emitting chip can be normally lit when the light-emitting chip is disposed on the light-emitting backplane during the transfer process. Moreover, in this embodiment, it is not necessary to wait for the light-emitting chip and the light-emitting backplane to complete bonding. As long as the electrical connection between the light-emitting chip and the light-emitting backplane is formed, the light-emitting chip can be powered on and detected by applying pressure. The detection process is convenient and simple, and the detection can be completed when the bonding material of the light-emitting chip has not solidified. If a defective pixel is found, the light-emitting chip with the defective pixel can be easily removed, simplifying the repair process.

[0086] As in the foregoing example, each piezoelectric material layer can correspond to a single light-emitting chip, and the positions of each piezoelectric material layer and the second height region of the first conductive layer respectively correspond to the two electrodes of a light-emitting chip.

[0087] In another example, as Figure 10 shown, a plurality of piezoelectric material layers 22 are arranged in an array in the direction of the connection line of the two electrodes of the light-emitting chip. The distance d1 between every two adjacent piezoelectric material layers 22 and the distance between every two adjacent second height regions 212 are equal to the distance d2 between every three adjacent light-emitting chips in the direction of the connection line of the two electrodes. Based on such a relationship between the chip detection board and the light-emitting chip, before transferring the light-emitting chip to the light-emitting backplane, it includes transferring the light-emitting chip to the transfer substrate, and arranging the positive and negative electrode positions of every two adjacent light-emitting chips in the direction of the connection line of the two electrodes of the light-emitting chip in an inverted manner. For example Figure 10Among them, the positive electrode 41 of the first light-emitting chip 401 is located on the left side in the illustrated direction, and the negative electrode 42 is located on the right side in the illustrated direction. The second light-emitting chip 402 adjacent to the first light-emitting chip 401 is rotated 180 degrees relative to the first light-emitting chip 401 in a plane parallel to the light-emitting backplane. The position of the positive electrode 41 of the second light-emitting chip 402 is switched to the right side in the illustrated direction, and the position of the negative electrode 42 is switched to the left side in the illustrated direction. Similarly, the third light-emitting chip 403 adjacent to the second light-emitting chip 402 also has the positions of its positive and negative electrodes reversed relative to those of the second light-emitting chip 402. The positive electrode 41 of the third light-emitting chip 403 is located on the left side in the illustrated direction, and the negative electrode 42 is located on the right side in the illustrated direction, and so on. This is equivalent to the positive and negative electrodes of each light-emitting chip in this direction being opposite to those of the adjacent light-emitting chip.

[0088] As Figure 11 shown, when each piezoelectric material layer can correspond to a single light-emitting chip, the electrodes of the light-emitting chips can be arranged in the same order. For example, Figure 11 in the example shown, the positive electrodes 41 of the light-emitting chips are all on the left side (with the illustrated direction as a reference), and the negative electrodes 42 are all on the right side. Exemplarily, Figure 12 an example shows a top view schematic diagram of a chip detection board corresponding to Figure 11 .

[0089] As Figure 13 shown in the example, when the two electrodes of the light-emitting chip are connected, among the light-emitting chips in the direction L of the connection line of the electrodes (taking the Figure 13 illustrated direction as an example, that is, the light-emitting chips in the same row in the illustration), the same electrodes of adjacent light-emitting chips are always arranged close to each other. This enables the same electrodes of two adjacent light-emitting chips to jointly contact a second height region or a second conductive layer. Figure 14 An example shows a top view schematic diagram of a chip detection board corresponding to Figure 13 . Exemplarily, the fifth conductive layer or the sixth conductive layer corresponding to the same electrodes of two adjacent light-emitting chips on the light-emitting backplane can also be connected and formed into a larger region. That is, each electrode of the light-emitting chip can share the fifth conductive layer or the sixth conductive layer with the adjacent light-emitting chip close to this electrode. It can be understood that in this example, by alternately arranging the electrode order of the light-emitting chips, a second conductive layer, the second height region of the first conductive layer, the fifth conductive layer, and the sixth conductive layer can be shared by two light-emitting chips, and at least one of the piezoelectric material layer, the second conductive layer, the second height region of the first conductive layer, the fifth conductive layer, and the sixth conductive layer can be formed into a larger size. This reduces the total number of various structures required on the chip detection board, making the manufacturing difficulty and the requirement for precision of the chip detection board lower, which is beneficial to the yield rate and cost control.

[0090] In the above example, the same type of electrodes of the light-emitting chips in the same column (with the illustrated direction as a reference) are located on the same side. Therefore, in some embodiments, the piezoelectric material layer can also correspond to at least two light-emitting chips in the same column. Enabling at least two light-emitting chips to share the same piezoelectric material layer is also beneficial for reducing the number of piezoelectric material layers on the chip detection board and increasing the volume of a single piezoelectric material layer.

[0091] To better understand the chip transfer method of this embodiment, a method of transferring a light-emitting chip to a light-emitting backplane will be further described below. As Figure 15 shown, when transferring the light-emitting chip to the light-emitting backplane, before the bonding material of the light-emitting chip completely solidifies, applying a pressure to the light-emitting backplane sufficient to generate a current in the piezoelectric material layer sufficient to drive the light-emitting chip to work includes:

[0092] S1041. Provide a light-transmitting substrate provided with light-emitting chips;

[0093] The light-transmitting substrate can be the growth substrate for growing the light-emitting chips or a transfer substrate. The material of the light-transmitting substrate can be any one of, including but not limited to, glass, sapphire, and quartz. As Figure 16 , the electrodes of the light-emitting chip 4 are arranged on the side away from the light-transmitting substrate 5, and the light-emitting chip 4 is connected to the light-transmitting substrate 5 through the side without electrodes. The light-transmitting substrate includes but is not limited to being completely light-transmitting or partially light-transmitting, that is, it can be completely transparent or semi-transparent. However, it should be understood that in order to observe the light-emitting situation of the light-emitting chip, the light-transmitting substrate should at least ensure that when the light-emitting chip emits light, the position of the defective pixels can be identified.

[0094] S1042. Oppose the side of the light-transmitting substrate provided with the light-emitting chips to the light-emitting backplane, and align the electrodes of the light-emitting chips with the third conductive layer and the fourth conductive layer of the light-emitting backplane;

[0095] This alignment process can be carried out by, including but not limited to, CCD (Charge Coupled Device) vision alignment technology. In some examples, it can also be assisted by setting positioning holes, positioning marks, etc. Exemplarily, one type of electrode (such as the positive electrode) of the light-emitting chip is aligned with the third conductive layer, and the other type of electrode (such as the negative electrode) is aligned with the fourth conductive layer.

[0096] S1043. Move the light-transmitting substrate closer to the light-emitting backplane. When the light-emitting chip contacts the light-emitting backplane, continue to press down the light-transmitting substrate to apply a pressure to the light-emitting backplane sufficient to generate a current in the piezoelectric material layer sufficient to drive the light-emitting chip to work;

[0097] It should be noted that as Figure 17, during this process, a bonding material 43 is provided on the electrodes of the light-emitting chip 4 and / or corresponding areas of the light-emitting backplane 5. After the light-emitting chip 4 contacts the light-emitting backplane 5, the bonding material 43 can be used for bonding. It can be understood that although the light-emitting chip has not been bonded and fixed, since the electrodes of the light-emitting chip have contacted the third conductive layer and the fourth conductive layer of the light-emitting backplane, and the bonding material is also conductive, in fact, the light-emitting chip has achieved electrical connection with the light-emitting backplane, that is, the two can achieve current transfer. Therefore, under normal circumstances, applying a pressure F to the light-transmitting substrate to form a current in the piezoelectric material layer can cause the light-emitting chip to emit a certain amount of light.

[0098] At this time, through the light-transmitting substrate, the light-emitting situation of the light-emitting chip can be observed to complete the detection. Exemplarily, an image acquisition device can be set to record the light-emitting situation of the light-emitting chip, and the position of the defective pixel of the light-emitting chip can be determined by means of computer vision and the like. The image acquisition device includes but is not limited to various optical sensors. The light-emitting backplane of this embodiment includes but is not limited to a display backplane and other circuit boards that emit visible light; it can also include a circuit board that emits invisible light in the sensor. For invisible light, the optical sensor can also be an optical sensor that collects invisible light. The image acquisition device can be set on the picking device that picks up the light-transmitting substrate, or at other positions that are convenient for collecting the light of the light-emitting chip.

[0099] After the transfer of the light-emitting chip is completed, the light-transmitting substrate is removed. If the light-transmitting substrate is a growth substrate for growing the chip, methods such as but not limited to LLO (Laser Lift Off) can be used to ensure that the light-emitting chip is smoothly peeled off from the growth substrate; if the light-transmitting substrate is a transfer substrate, the light-emitting chip is usually arranged on the transfer substrate through an adhesive layer that can release its adhesion, and the light-emitting chip is separated from the transfer substrate by releasing the adhesion of the adhesive layer.

[0100] Such as Figure 18 , in this embodiment, after applying a pressure sufficient to deform the piezoelectric material layer to the light-emitting backplane, it further includes:

[0101] S201. Remove the light-emitting chip that fails to emit light successfully or whose light-emitting situation does not meet the predetermined conditions during the deformation process of the piezoelectric material layer;

[0102] The above-mentioned predetermined conditions can be defined according to the actual situation. For example, in one example, it can be determined whether the detected light-emitting brightness of the light-emitting chip reaches a certain set threshold, or whether the brightness difference between a certain light-emitting chip and most other light-emitting chips is greater than the corresponding set threshold, etc.

[0103] It can be understood that since the chip transfer method of this embodiment observes the light-emitting situation of the light-emitting chip when the light-emitting chip is in a state where bonding has not been completed, when removing the light-emitting chip, operations such as debonding are not required, greatly reducing the complexity of the process of removing the light-emitting chip, and this is also conducive to ensuring the good quality of the final product.

[0104] S202. Re-transfer a light-emitting chip to the vacancy formed by removing the non-successfully light-emitting light-emitting chip;

[0105] The repair of the vacancy can be achieved by selectively transferring the light-emitting chip. The specific process of selectively transferring the light-emitting chip may not be limited in this embodiment. However, in some implementation processes, when re-transferring the light-emitting chip to the vacancy, sufficient pressure can also be applied after the light-emitting chip contacts the light-emitting backplane to detect the repaired light-emitting chip.

[0106] The chip transfer method of this embodiment can realize the power supply and drive of the light-emitting chip during the process of transferring the light-emitting chip by using the above chip detection board and adopting a light-emitting backplane that can directly form a conductive path with the chip detection board, detect the bad point situation of the light-emitting chips arranged on the light-emitting backplane during the process of transferring the light-emitting chips, is convenient for timely replacement and repair in some implementation processes, and can be repaired before the bonding material of the light-emitting chip completely solidifies, avoiding the step of debonding and reducing the complexity and difficulty of repair.

[0107] Another alternative embodiment of the present invention:

[0108] This embodiment provides a display backplane. Please refer to Figure 7 , the display backplane includes a light-emitting chip, a third conductive layer, a fourth conductive layer, a fifth conductive layer, and a sixth conductive layer. The third conductive layer and the fourth conductive layer are arranged on the first surface of the display backplane, and the two electrodes of the light-emitting chip are respectively connected to the third conductive layer and the fourth conductive layer. The light-emitting chips on the display backplane are transferred to the display backplane by the chip transfer method of the above embodiment.

[0109] In some implementation manners, the light-emitting chips are arranged in an array, and the positions of the positive and negative electrodes of each adjacent light-emitting chip in the connection direction of the two electrodes of the light-emitting chip are arranged in reverse; the same electrodes of adjacent light-emitting chips are connected to the same fifth conductive layer or sixth conductive layer.

[0110] The display backplane of this embodiment can detect bad points and perform repairs during the process of transferring chips, and has a high yield and good quality of the display backplane.

[0111] This embodiment further provides a display device, including a frame and a display backplane. The display backplane is fixed to the frame, and the display backplane on this display device is the display backplane described above in this embodiment. The yield rate of this display device is high and the quality is good. The display device in this embodiment includes, but is not limited to, various electronic devices that use a display backplane manufactured by a light-emitting chip for display, such as, but not limited to, various smart mobile terminals, PCs (Personal Computers), monitors, electronic billboards, etc. The display backplane can be further formed into a display panel of these electronic devices.

[0112] It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A chip detection board, characterized in that, Comprising: Substrate body; A first conductive layer provided on one side of the substrate body. The first conductive layer includes a first height region and a second height region. The first height region is relatively close to the substrate body, and the second height region is relatively far from the substrate body; a piezoelectric material layer provided on a part of the region of the first conductive layer. The piezoelectric material layer is provided on the side of the first conductive layer away from the substrate body. The first side of the piezoelectric material layer is electrically connected to the first height region of the first conductive layer. When the piezoelectric material layer deforms in a direction perpendicular to the substrate body, a voltage is generated between the first side and the second side, and the second side is the side opposite to the first side; a second conductive layer provided at least on the side of the piezoelectric material layer away from the substrate body, and the second conductive layer is electrically connected to the second side of the piezoelectric material layer. The second height region includes any one of the following: A spacer is provided between the first conductive layer and the substrate body, and the second height region is formed at the position of the spacer on the first conductive layer; the first conductive layer includes a conductive plane with equal thickness and a conductor provided on a part of the region on the side of the conductive plane away from the substrate body, and the second height region is formed at the position of the conductor.

2. The chip detection board according to claim 1, wherein, The chip detection board includes a plurality of the piezoelectric material layers, and the piezoelectric material layers are arranged in an array, and each first conductive layer is connected to a plurality of the piezoelectric material layers.

3. A chip transfer method, characterized in that, Comprising: Providing a chip detection board, where the chip detection board is the chip detection board according to claim 1 or 2; Providing a light-emitting backplane, where the light-emitting backplane includes a third conductive layer and a fourth conductive layer provided on the first surface and a fifth conductive layer and a sixth conductive layer provided on the second surface. The third conductive layer and the fourth conductive layer correspond to the electrodes of the light-emitting chips to be transferred and are used to be electrically connected to the electrodes of the light-emitting chips. The fifth conductive layer is electrically connected to the third conductive layer, and the sixth conductive layer is electrically connected to the fourth conductive layer; disposing the light-emitting backplane on the chip detection board, the fifth conductive layer is electrically connected to the second height region of the first conductive layer, and the sixth conductive layer is electrically connected to the second conductive layer; transferring the light-emitting chips to the light-emitting backplane, and before the bonding material of the light-emitting chips completely solidifies, applying a pressure to the light-emitting backplane sufficient to cause the piezoelectric material layer to generate a current sufficient to drive the light-emitting chips to work.

4. The chip transfer method according to claim 3, wherein The chip detection board includes a plurality of the piezoelectric material layers, and the piezoelectric material layers are arranged in an array. The distance between every two adjacent piezoelectric material layers and every two adjacent second height regions in the direction of the connection line of the two electrodes of the light-emitting chip is equal to the distance between every three adjacent light-emitting chips in the direction of the connection line of the two electrodes; before transferring the light-emitting chips to the light-emitting backplane, it includes: transferring the light-emitting chips to a transfer substrate, and arranging the positive and negative poles of every two adjacent light-emitting chips in the direction of the connection line of the two electrodes in an inverted manner.

5. The chip transfer method according to claim 3, wherein Transferring the light-emitting chip to the light-emitting backplane, before the bonding material of the light-emitting chip is completely solidified, applying a pressure to the light-emitting backplane sufficient to generate a current in the piezoelectric material layer sufficient to drive the light-emitting chip to operate includes: providing a light-transmitting substrate provided with a light-emitting chip, and a side of the light-emitting chip provided with the electrode is away from the light-transmitting substrate; Opposing the side of the light-transmitting substrate provided with the light-emitting chip to the light-emitting backplane, and aligning the electrodes of the light-emitting chip with the third conductive layer and the fourth conductive layer of the light-emitting backplane; making the light-transmitting substrate approach the light-emitting backplane, and after the light-emitting chip contacts the light-emitting backplane, continue to press down the light-transmitting substrate to apply a pressure to the light-emitting backplane sufficient to generate a current in the piezoelectric material layer sufficient to drive the light-emitting chip to operate.

6. The chip transfer method according to any one of claims 3 to 5, characterized in that, After applying a pressure sufficient to deform the piezoelectric material layer to the light-emitting backplane, it further includes: removing the light-emitting chips that do not emit light successfully or whose light-emitting conditions do not reach the predetermined conditions during the deformation process of the piezoelectric material layer; re-transferring light-emitting chips to the vacancies formed by removing the light-emitting chips.

7. A display backplane, characterized in that, Including: A light-emitting chip; further including a third conductive layer and a fourth conductive layer provided on the first surface and a fifth conductive layer and a sixth conductive layer provided on the second surface, the third conductive layer and the fourth conductive layer are electrically connected to the electrodes of the light-emitting chip, the fifth conductive layer is electrically connected to the third conductive layer, and the sixth conductive layer is electrically connected to the fourth conductive layer; the light-emitting chip is transferred to the display backplane by the chip transfer method according to any one of claims 3 to 6.

8. The display backplane according to claim 7, wherein The light-emitting chips are arranged in an array, and the positions of the positive and negative electrodes of each adjacent light-emitting chip in the connection direction of the two electrodes of the light-emitting chip are arranged in reverse; the same electrodes of adjacent light-emitting chips are connected to the same fifth conductive layer or the same sixth conductive layer.

9. A display device, characterized in that, Including a frame and a display backplane, the display backplane is fixed on the frame, and the display backplane is the display backplane according to claim 7 or 8.

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