Display panel manufacturing method, display panel and display device

Abstract

The present application provides a method for preparing a display panel, a display panel and a display device. The preparation method accommodates components in a groove of a first substrate, and then fills the groove with a protective layer so that the protective layer covers the components, thereby increasing the overall volume of the components (the overall volume of the components covered by the protective layer). The components covered by the protective layer are then transferred to the driving substrate, and the problem of transferring a large number of small-sized and high-density components is converted into a problem of transferring a large number of large-sized and low-density components, thereby greatly reducing the difficulty of transferring components, improving the efficiency of transferring components, and improving the yield of the display panel.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a method for preparing a display panel, a display panel and a display device. Background Art

[0002] With the continuous development of display technology, light emitting diode (LED) display technology as a new type of display technology has gradually become one of the research hotspots. Among them, micro light emitting diodes (Micro LED) and sub-millimeter light emitting diodes (Mini LED) with smaller sizes are increasingly used in large-size backlight sources due to their small size and thin backlight thickness. Micro-LED and mini-LED technologies are to shrink the size of existing LEDs to less than 100um and between 100 and 300um respectively.

[0003] However, the preparation process of Mini-LED and Micro-LED is difficult and technically complex, especially its key technology: mass transfer technology. Since the development of mass transfer technology, many technical branches have emerged, such as precision grasping technology (electrostatic force, van der Waals force, magnetic force), self-assembly technology (fluid self-assembly), selective release (patterned laser) technology, etc. However, the mass transfer technology of direct transfer or indirect transfer in the existing technology not only requires precise alignment, but also has complex processes and high costs. Due to the limited precision of Mini-LED and Micro-LED process equipment and the small size of Mini-LED and Micro-LED, it is difficult to meet the precision specification requirements of Mini-LED and Micro-LED mass transfer. Although the one-to-one method of vacuum suction LED can be used for transfer, the size of the vacuum tube of vacuum suction LED is limited, which is no longer applicable to smaller LEDs. At the same time, because the size of Micro-LED is very small, for large-size display panels, the number of LEDs required is huge, which can reach tens of millions or hundreds of millions. If the one-to-one transfer method is still used, the transfer efficiency will be greatly reduced. Summary of the invention

[0004] In response to the above problems, the present application provides a method for preparing a display panel, a display panel and a display device, which can solve the technical problems of difficult and low efficiency transfer process of Micro / mini-LED display panels in the prior art.

[0005] In a first aspect, the present application provides a method for preparing a display panel, comprising:

[0006] Providing a first substrate; wherein a plurality of grooves are provided on the first substrate;

[0007] Accommodating a plurality of components in the plurality of grooves of the first substrate to form a transfer substrate; wherein a first pad is disposed on a side of the component away from the bottom of the groove;

[0008] Filling a protective layer in the groove of the transfer substrate so that the component in the groove is at least partially covered by the protective layer; wherein the protective layer does not cover the side of the first pad of the component away from the bottom of the groove;

[0009] A driving substrate is provided, the driving substrate is aligned with the side where the first pad of the component is located, and the first substrate is removed to transfer the component covered by the protective layer to the driving substrate.

[0010] In some embodiments, in the method for manufacturing the display panel, the orthographic projection of the component on the first substrate is located within the orthographic projection range of the groove on the first substrate, and the component does not contact the side wall of the groove.

[0011] In some embodiments, in the method for manufacturing the display panel, the step of filling the groove of the transfer substrate with a protective layer comprises the following steps:

[0012] A protective layer is filled in the groove of the transfer substrate, so that the protective layer at least partially fills the gap between the component and the side wall of the groove.

[0013] In some embodiments, in the method for manufacturing the display panel, in the first substrate, the connection between the side wall and the bottom of the groove is provided with an inclined chamfer, an arc chamfer or a right angle.

[0014] In some embodiments, in the method for manufacturing the display panel, a side of the driving substrate used for carrying the components is provided with a plurality of groups of second pads corresponding to the first pads of each of the components; the method further includes:

[0015] Tilt the driving substrate so that each of the components on the driving substrate covered by the protective layer slides respectively until the first pads thereof contact the corresponding second pads;

[0016] Connect the first pad of each component to the corresponding second pad.

[0017] In some embodiments, in the method for preparing the display panel, when the first pads of each of the components covered by the protective layer on the driving substrate are in contact with the corresponding second pads, any two adjacent components covered by the protective layer are in contact with each other.

[0018] In some embodiments, in the method for manufacturing the display panel, in the step of tilting the drive substrate, the components do not leave the drive substrate.

[0019] In some embodiments, in the method for manufacturing the display panel, the protective layer does not cover the surface of the first substrate opposite to the driving substrate.

[0020] In some embodiments, in the method for preparing the display panel, the material of the protective layer includes silica gel.

[0021] In some embodiments, in the method for manufacturing the display panel, in the first substrate, the inner surface of the groove is covered with a chrome-plated metal layer.

[0022] In some embodiments, in the above-mentioned method for preparing a display panel, the components include a light-emitting device;

[0023] The first pads of the component include an anode pad and a cathode pad that are spaced apart from each other, wherein in the transfer substrate, the orthographic projections of the anode pad and the cathode pad on the first substrate have different shapes.

[0024] In some embodiments, in the method for manufacturing the display panel, the protective layer is also filled in the gap between the anode pad and the cathode pad.

[0025] In some embodiments, in the above-mentioned method for manufacturing a display panel, accommodating a plurality of components in the plurality of grooves of the first substrate to form a transfer substrate comprises the following steps:

[0026] Providing a second substrate; wherein the second substrate comprises a second base and the plurality of components disposed on the second base, and the first pads of the components are bonded to the second base;

[0027] The second substrate is aligned with the first substrate so that the components are embedded in the groove of the first substrate, and the second base is removed to transfer the components to the groove of the first substrate, thereby forming the transfer substrate.

[0028] In some embodiments, in the above-mentioned method for preparing a display panel, in the second substrate, the first pad of the component is bonded to the second base through a photosensitive adhesive layer;

[0029] Before the step of removing the second substrate, the method further comprises:

[0030] The photosensitive adhesive layer is irradiated with light of a preset wavelength to reduce the viscosity of the photosensitive adhesive layer, so that the second substrate is separated from the first pad of the component.

[0031] In some embodiments, in the method for preparing the display panel, the second substrate is prepared by the following steps:

[0032] Providing a third substrate, and forming the plurality of components on the third substrate; wherein the first pads of the components are located on a side of the components away from the third substrate;

[0033] Providing a first protective film, and aligning the first protective film with the third substrate so that the first protective film is bonded to the first pad of the component;

[0034] removing the third substrate to transfer the components to the first protective film;

[0035] Providing a second protective film, and aligning the second protective film with the first protective film so that the second protective film is bonded to a side of the component away from the first protective film; wherein the bonding force between the second protective film and the component is greater than the bonding force between the first protective film and the component;

[0036] removing the first protective film to transfer the components to the second protective film;

[0037] Providing the second substrate, and aligning the second substrate and the second protective film so that the second substrate is bonded to the first pad of the component; wherein the bonding force between the second substrate and the component is greater than the bonding force between the second protective film and the component;

[0038] The second protective film is removed to transfer the components to the second base, thereby forming the second substrate.

[0039] In some embodiments, in the above-mentioned method for manufacturing a display panel, in the first substrate, the distance between the centers of any two adjacent grooves is a preset distance;

[0040] Removing the second protective film to transfer the plurality of components to the second base, thereby forming the second substrate, comprises the following steps:

[0041] The second protective film is removed to transfer the components to the second substrate, and the second substrate is stretched until the distance between the centers of any two adjacent components on the second substrate reaches the preset distance, thereby forming the second substrate.

[0042] In a second aspect, the present application provides a display panel prepared by the preparation method as described in any one of the first aspects, comprising a driving substrate and a plurality of components arranged on the driving substrate;

[0043] A first pad is disposed on a side of the component close to the drive substrate, the component is at least partially covered by a protective layer, and the protective layer does not cover the side of the first pad of the component close to the drive substrate.

[0044] In some embodiments, in the above display panel, a plurality of groups of second pads are provided on a side of the driving substrate close to the components;

[0045] The first pad of each of the components is electrically connected to the corresponding second pad.

[0046] In some embodiments, in the above display panel, any two adjacent components covered by the protective layer are in contact with each other.

[0047] In a third aspect, the present application provides a display device, comprising a display panel as described in any one of the second aspects.

[0048] By adopting the above technical solution, at least the following technical effects can be achieved:

[0049] The present application provides a method for preparing a display panel, a display panel and a display device. The preparation method accommodates components in a groove of a first substrate, and then fills the groove with a protective layer so that the protective layer covers the components, thereby increasing the overall volume of the components (the overall volume of the components covered by the protective layer). The components covered by the protective layer are then transferred to the driving substrate, and the problem of transferring a large number of small-sized and high-density components is converted into a problem of transferring a large number of large-sized and low-density components, thereby greatly reducing the difficulty of transferring components, improving the efficiency of transferring components, increasing the yield of the display panel, and reducing the process cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present application but do not constitute a limitation to the present application. In the accompanying drawings:

[0051] Figure 1 is a schematic flow chart of a method for preparing a display panel according to an exemplary embodiment of the present application;

[0052] Figure 2 is a schematic cross-sectional structural diagram of a first intermediate structure formed by relevant steps of a method for manufacturing a display panel shown in an exemplary embodiment of the present application;

[0053] Figure 3 is a schematic cross-sectional structural diagram of a second intermediate structure formed in relevant steps of a method for manufacturing a display panel shown in an exemplary embodiment of the present application;

[0054] Figure 4 is a schematic cross-sectional structural diagram of a third intermediate structure formed by relevant steps of a method for manufacturing a display panel shown in an exemplary embodiment of the present application;

[0055] Figure 5 is a schematic cross-sectional structural diagram of a fourth intermediate structure formed in relevant steps of a method for manufacturing a display panel shown in an exemplary embodiment of the present application;

[0056] Figure 6a is a partially enlarged schematic diagram of a transfer substrate shown in an exemplary embodiment of the present application;

[0057] Figure 6b is a schematic cross-sectional structure diagram of a component shown in an exemplary embodiment of the present application;

[0058] Figure 6c is a schematic projection diagram of a component on a first substrate shown in an exemplary embodiment of the present application;

[0059] Figure 7 It is a schematic flow chart of a method for preparing a transfer substrate shown in an exemplary embodiment of the present application;

[0060] Figure 8 It is a schematic diagram of the relevant steps of a method for preparing a transfer substrate shown in an exemplary embodiment of the present application;

[0061] Fig. 9 It is a schematic cross-sectional structure diagram of an intermediate structure formed by related steps of transferring a substrate of a display panel shown in an exemplary embodiment of the present application;

[0062] Fig.10 is a schematic flow chart of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0063] Fig.11 is a schematic cross-sectional structural diagram of a first intermediate structure formed by relevant steps of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0064] Fig.12is a schematic cross-sectional structural diagram of a second intermediate structure formed by relevant steps of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0065] Fig.13 is a schematic cross-sectional structural diagram of a third intermediate structure formed by relevant steps of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0066] Fig.14 is a schematic cross-sectional structural diagram of a fourth intermediate structure formed by relevant steps of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0067] Fig.15 is a schematic cross-sectional structural diagram of a fifth intermediate structure formed by relevant steps of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0068] Fig.16 is a schematic cross-sectional structural diagram of a sixth intermediate structure formed by relevant steps of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0069] Fig.17 is a schematic cross-sectional structural diagram of a seventh intermediate structure formed by relevant steps of a method for preparing a second substrate shown in an exemplary embodiment of the present application;

[0070] Fig.18 is a schematic cross-sectional structural diagram of a fifth intermediate structure formed in relevant steps of a method for manufacturing a display panel shown in an exemplary embodiment of the present application;

[0071] Fig.19 is a schematic structural diagram of a driving substrate shown in an exemplary embodiment of the present application;

[0072] Fig. 20 is a schematic diagram of a tilting process of a driving substrate shown in an exemplary embodiment of the present application;

[0073] In the drawings, the same reference numerals are used for the same components, and the drawings are not drawn to scale;

[0074] The accompanying drawings are marked as follows:

[0075] 11-first substrate; 111-groove; 12-component; 121-device body; 122-cathode pad; 123-anode pad; 13-protective layer; 14-driving substrate; 141-second pad; 142-base substrate; 143-baffle; 143a-universal roller; 144-slide rail; 15-second substrate; 15a-second base; 15b-third base; 15c-first protective film; 15d-second protective film; DETAILED DESCRIPTION

[0076] The following will describe the implementation methods of the present application in detail in conjunction with the accompanying drawings and embodiments, so that the implementation process of how the present application applies technical means to solve technical problems and achieve corresponding technical effects can be fully understood and implemented accordingly. The embodiments of the present application and the various features in the embodiments can be combined with each other without conflict, and the technical solutions formed are all within the scope of protection of the present application. In the drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0077] It should be understood that although the terms "first", "second", "third", etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as a second element, component, region, layer or part.

[0078] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present application. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0079] In order to thoroughly understand the present application, detailed structures and steps will be presented in the following description to illustrate the technical solution proposed by the present application. The preferred embodiments of the present application are described in detail below, but in addition to these detailed descriptions, the present application may also have other implementation methods.

[0080] First, because the precision of Mini-LED and Micro-LED process equipment needs to be less than ±1.5μm to accurately transfer to the target substrate, and the current precision of transfer equipment is ±34μm, it cannot meet the precision specification requirements of Mini-LED and Micro-LED mass transfer. If the traditional vacuum suction LED method is used for transfer, the vacuum tube can only reach about 80μm under the physical limit, and the size of Micro-LED is basically less than 50μm, so the vacuum adsorption method is no longer applicable to Micro-LED. At the same time, because the size of Micro-LED is very small, for large-size display panels, the number of LEDs required is huge, which can reach tens of millions or hundreds of millions. If the one-to-one transfer method is still used, the transfer efficiency will be greatly reduced.

[0081] Therefore, the present application provides a method for preparing a display panel, such as Figure 1 As shown, the preparation method comprises:

[0082] Step S110 : providing a first substrate 11 ; wherein a plurality of grooves 111 are disposed on the first substrate 11 .

[0083] Step S120: Figure 2 As shown, a plurality of components 12 are accommodated in a plurality of grooves 111 of a first substrate 11 to form a transfer substrate (not marked in the figure); wherein a first pad (not marked in the figure) is provided on a side of the component 12 away from the bottom of the groove 111 .

[0084] Step S130: Figure 3 As shown, a protective layer 13 is filled in the groove 111 of the transfer substrate, so that the component 12 in the groove 111 is at least partially covered by the protective layer 13; wherein the protective layer 13 does not cover the side of the first pad of the component 12 away from the bottom of the groove 111;

[0085] Step S140: providing a driving substrate 14, such as Figure 4 As shown, the driving substrate 14 is aligned with the side where the first pad of the component 12 is located, and the first substrate 11 is removed, as shown in FIG. Figure 5 As shown, the component 12 covered by the protective layer 13 is transferred to the driving substrate 14 ; wherein the first pad of the component 12 is located on a side of the component 12 close to the driving substrate 14 .

[0086] Among them, the lateral dimension of the groove 111 is larger than the lateral dimension of the component 12, so the protective layer 13 can cover the component 12, thereby increasing the overall volume of the component 12 (covering the component 12), thereby converting the problem of large-scale transfer of small-size and high-density components into a problem of large-scale transfer of large-size and low-density components, greatly reducing the difficulty of transferring the component 12, improving the transfer efficiency of the component 12, and improving the yield of the display panel.

[0087] In the present application, by using the first substrate 11, the small pitch transfer problem of the component 12 is converted into a large pitch transfer, which reduces the precision requirement of the component 12. Therefore, there is no need to use expensive high-precision equipment, which is low-cost and also reduces the difficulty of transfer.

[0088] In some embodiments, in the first substrate 11 , the connection between the side wall and the bottom of the groove 111 is provided with an inclined chamfer, an arc chamfer or a right angle.

[0089] In some embodiments, the connection between the side wall and the bottom of the groove 111 is provided with an inclined chamfer, such as Figure 6a shown.

[0090] In some embodiments, the component 12 may be a light-emitting device. It can be understood that the transfer method of the component 12 in the preparation method provided in the present application is applicable to the transfer technology of the light-emitting device.

[0091] Correspondingly, the inclined chamfer or circular chamfer at the connection between the side wall and the bottom of the groove 111 can modify the front view light output angle and light output effect of the component 12. Based on the optical simulation results of the actual application scenario, the desired optical effect can be achieved by changing the size of the inclined chamfer of the groove 111 on the designed first substrate 11 or the radius of the circular chamfer.

[0092] In some embodiments, the size of the chamfer of the groove 111 may be 45°, that is, the inclination angle α formed between the groove 111 and the side surface of the component 12 is 45°.

[0093] In some embodiments, the connection between the side wall and the bottom of the groove 111 is at a right angle, which is more conducive to the subsequent steps in the display panel.

[0094] In some embodiments, the plurality of grooves 111 on the first substrate 11 are in an array shape, and the number of the transverse and longitudinal grooves 111 depends on the number of the transverse and longitudinal components 12 required in the final display panel.

[0095] In some embodiments, when the component 12 is a light-emitting device, the size of the display (AA) area of ​​a 27-inch product is: 596.736mm×335.664mm. According to the pitch of the component 12 (the distance between the center of the device and the center of the device) of 0.06mm, the number of components 12 required for the backlight panel (display panel) is about 9946×5595, a total of 55748580. Therefore, correspondingly, the array arrangement of the above-mentioned multiple grooves 111 on the first substrate 11 is 9946×5595, which can realize the transfer of all components 12 at one time without the need for batch transfer, which greatly improves the transfer efficiency.

[0096] In some embodiments, the material of the first substrate 11 is alloy metal, and correspondingly, the formation of the groove 111 on the first substrate 11 can be performed by micro-electric spark wire cutting. The processing accuracy can reach ±1μm, thereby meeting the requirements for transfer accuracy. After the processing is completed, the inner surface of the mold is chrome-plated to form a chrome-plated metal layer to reduce the adhesion between the protective layer 13.

[0097] In some embodiments, in the transfer substrate, since the orthographic projection of the component 12 on the first substrate 11 is located within the orthographic projection range of the groove 111 on the first substrate 11, that is, the lateral dimension of the groove 111 is larger than the lateral dimension of the component 12, the component 12 may not contact the side wall of the groove 111, such as Figure 2 shown.

[0098] Correspondingly, the step of filling the groove 111 of the transfer substrate with the protective layer 13 in step S130 is mainly to fill the gap between the component 12 and the side wall of the groove 111, so that the protective layer 13 at least partially fills the gap between the component 12 and the side wall of the groove 111.

[0099] In some embodiments, the gaps between the component 12 and the sidewalls of the groove 111 are filled with the protective layer 13 , so that the sides of the component 12 are covered by the protective layer 13 , thereby improving the uniformity of the coating of the protective layer 13 and reducing the difficulty of transferring the component 12 .

[0100] It can be understood that after step S130 is completed, a circle of protection layer 13 is wrapped around the component 12, so that the overall size of the component 12 is increased.

[0101] In some embodiments, the distance between each position on the side of the component 12 and the side wall of the groove 111 is the same, so that the thickness of the protective layer 13 wrapped around the component 12 is consistent, improving the uniformity of the coating of the protective layer 13 and further reducing the difficulty of transferring the component 12.

[0102] In some embodiments, the material of the protection layer 13 includes silicone, which may be transparent silicone.

[0103] In some embodiments, in the first substrate 11 , the inner surface of the groove 111 is covered with a chrome-plated metal layer.

[0104] Since the adhesion between the silicone and the chrome-plated metal layer is poor, but the adhesion between the silicone and the component 12 is strong, when the first substrate 11 is removed in step S140 , the component 12 covered by the protective layer 13 can be easily separated from the first substrate 11 , thereby achieving the removal of the first substrate 11 .

[0105] In some embodiments, before removing the first substrate 11 in step S140, the driving substrate 14 may be aligned with the side of the transfer substrate where the components 12 are located by a robot arm to form a Figure 4 The intermediate structure shown is flipped so that the transfer substrate is located above the drive substrate 14, so as to facilitate the subsequent removal of the first substrate 11 and the transfer of the components 12. After flipping, it is placed on the base, and the components 12 are separated from the first substrate 11 by an ultrasonic vibration auxiliary device to complete demoulding.

[0106] In some embodiments, the protection layer 13 does not cover the surface of the first substrate 11 opposite to the driving substrate 14 .

[0107] In some embodiments, the silicone used to prepare the protective layer 13 may be a transparent silicone glue, and the preparation of the protective layer 13 may be achieved by dispensing.

[0108] In some embodiments, automated equipment can be used for batch dispensing, and the glue amount can be controlled to ensure that the glue surface does not cover the surface of the first substrate 11 that is opposite to the driving substrate 14 , thereby ensuring good alignment between the first substrate 11 and the driving substrate 14 .

[0109] In some embodiments, when the component 12 is a light emitting device, such as Figure 6b and 6c As shown, the first pad of the component 12 includes an anode pad 123 and a cathode pad 122 arranged at intervals, wherein, in the transfer substrate, the shapes of the positive projections of the anode pad 123 and the cathode pad 122 on the first substrate 11 are different. This ensures that the polarity can be distinguished by a microscope or other equipment in subsequent steps. In addition, the component 12 also includes a device body 121.

[0110] In some embodiments, the shape of the orthographic projection of the anode pad 123 on the first substrate 11 may be a rectangle, and the shape of the orthographic projection of the cathode pad 122 on the first substrate 11 may be a circle.

[0111] In some embodiments, the orthographic projection of the component 12 as a whole on the first substrate 11 is in the shape of a square.

[0112] In some embodiments, the protection layer 13 is also filled in the gap between the anode pad 123 and the cathode pad 122 .

[0113] In some embodiments, the lateral dimension (length, width, diagonal line, diameter, etc.) of the groove 111 is 60um, and the lateral dimension (length, width, diagonal line, diameter, etc.) of the component 12 is less than 50um. Therefore, the preparation method in the present application can be applied to the component 12 with a size less than 50μm, and realize the transfer of the micro-sized component 12.

[0114] In some embodiments, the orthographic projection of the component 12 on the first substrate 11 may be a square of 40*40 μm.

[0115] In some embodiments, when the component 12 is a light-emitting device, the component 12 may be a mini LED or a micro LED.

[0116] The cross-sectional dimensions (length, width, diagonal, diameter, etc.) of the mini LED are between about 100 μm and about 300 μm, and the thickness can be 100 μm. The cross-sectional dimensions (length, width, diagonal, diameter, etc.) of the micro LED are below about 100 μm.

[0117] Correspondingly, the component 12 includes an anode layer, a light-emitting layer, a cathode layer, and a sapphire layer stacked in sequence along the thickness direction. The anode pad 123 and the cathode pad 122 are electrically connected to the anode layer and the cathode layer, respectively, and are used to lead out the anode layer and the cathode layer, respectively. The anode pad 123 and the cathode pad 122 are located on the same side of the component 12.

[0118] In some embodiments, the material of the anode is a P-type GaN layer.

[0119] In some embodiments, the material of the cathode is an N-type GaN layer.

[0120] In some embodiments, the material of the light emitting layer is a GaN multi-quantum well active layer.

[0121] In some embodiments, the light-emitting side of component 12 is arranged opposite to the first solder pad. Correspondingly, in the above-mentioned transfer substrate, the first solder pad of component 12 is located on the side of component 12 away from the bottom of groove 111, and the light-emitting side of component 12 is located on the side of component 12 close to the bottom of groove 111.

[0122] Correspondingly, in the process of filling the protection layer 13 in the groove 111 of the transfer substrate in step S130 , since the light-emitting side of the component 12 is attached to the bottom of the groove 111 , the protection layer 13 may not cover the light-emitting side of the component 12 .

[0123] Among them, since the light output from the side of the component 12 is large, the protection layer 13 can block part of the light output from the side, reduce energy loss, and improve the light output efficiency of the component 12.

[0124] In some embodiments, see Figure 7 , step S120 may include the following steps:

[0125] Step S122: providing a second substrate 15; wherein the second substrate 15 comprises a second base 15a and a plurality of components 12 disposed on the second base 15a, and the first pads of the components 12 are bonded to the second base 15a;

[0126] Step S124: Figure 8 and Fig. 9 As shown, the second substrate 15 is aligned with the first substrate 11 so that the component 12 is embedded in the groove 111 of the first substrate 11, and the second base 15a is removed to transfer the component 12 to the groove 111 of the first substrate 11, thereby forming Figure 2 The transfer substrate is shown.

[0127] In some embodiments, in the second substrate 15 , the first pads of the components 12 are bonded to the second base 15 a via a photosensitive adhesive layer (not shown in the figure).

[0128] Correspondingly, before removing the second base 15a in the second substrate 15 in step S124, the method further includes: irradiating the photosensitive adhesive layer with light of a preset wavelength to reduce the viscosity of the photosensitive adhesive layer, so that the second base 15a is separated from the first pad of the component 12.

[0129] In some embodiments, the photosensitive adhesive layer may be UV adhesive. Correspondingly, the light of the preset wavelength refers to ultraviolet light. The irradiation of ultraviolet light can reduce the viscosity of the UV adhesive, so that the second substrate 15a is separated from the first pad of the component 12.

[0130] Since there is no adhesion between the component 12 and the first substrate 11 in step S124, the first substrate 11 cannot exert an adhesive force on the component 12 during the removal of the second substrate 15a, so the second substrate 15a and the component 12 need to be bonded with a photosensitive adhesive layer with variable viscosity. In step S124, the viscosity of the photosensitive adhesive layer is reduced to separate the second substrate 15a from the first pad of the component 12. In the previous transfer process, the second substrate 15a and the first pad of the component 12 are both bonded and fixed by the photosensitive adhesive layer to prevent the component 12 from falling.

[0131] In some embodiments, the second substrate 15 a may be made of polyvinyl chloride (PVC).

[0132] In some embodiments, see Fig.10 In step S122, the second substrate 15 is prepared by the following steps:

[0133] Step S122a: providing a third substrate 15b, and forming a plurality of components 12 on the third substrate 15b, such as Fig.11 As shown; wherein the first pad of the component 12 is located on a side of the component 12 away from the third substrate 15b;

[0134] Step S122b: providing a first protective film 15c, and aligning the first protective film 15c with the third substrate 15b, so that the first protective film 15c is bonded to the first pad of the component 12, such as Fig.12 As shown;

[0135] Step S122c: Fig.13 As shown, the third substrate 15b is removed to transfer the component 12 to the first protective film 15c;

[0136] Step S122d: providing a second protective film 15d, and aligning the second protective film 15d with the first protective film 15c, so that the second protective film 15d is bonded to the side of the component 12 away from the first protective film 15c, such as Fig.14 As shown; wherein, the bonding force between the second protective film 15d and the component 12 is greater than the bonding force between the first protective film 15c and the component 12;

[0137] Step S122e: Fig.15 As shown, the first protective film 15c is removed to transfer the component 12 to the second protective film 15d;

[0138] Step S122f: providing a second substrate 15a, and aligning the second substrate 15a with the second protective film 15d, so that the second substrate 15a is bonded to the first pad of the component 12, such as Fig.16 As shown; wherein the bonding force between the second substrate 15a and the component 12 is greater than the bonding force between the second protective film 15d and the component 12;

[0139] Step S122g: Fig.17 As shown, the second protective film 15 d is removed to transfer the component 12 to the second base 15 a , thereby forming the second substrate 15 .

[0140] It is understandable that, in the process of preparing the second substrate 15, in the process of aligning and attaching the protective film or the base, in order to facilitate the attachment process, before attachment, the side of the component 12 to be attached needs to face upward, and in the process of removing the protective film or the base, in order to facilitate the removal process (film tearing process), before the removal process, the side of the component 12 to be torn needs to face upward. Therefore, in the process of preparing the second substrate 15, the formed intermediate structure can be flipped as needed, so that the side of the component 12 to be processed is set upward.

[0141] Among them, the third substrate 15b is the formation substrate of the component 12. When the component 12 is a light-emitting device, the light-emitting side of the component 12 is located on the side close to the third substrate 15b. The separation between the third substrate 15b and the component 12 can be performed by laser stripping, polishing and etching.

[0142] Subsequently, the removal of the first protective film 15 c and the second protective film 15 d may be performed by mechanical peeling according to the difference in viscosity of the protective films or substrates disposed on opposite sides of the component 12 .

[0143] Correspondingly, since the bonding force between the second protective film 15d and the component 12 is greater than the bonding force between the first protective film 15c and the component 12, during the process of removing (tearing off) the first protective film 15c in step S122e, the component 12 and the second protective film 15d remain bonded.

[0144] Correspondingly, since the bonding force between the second substrate 15a and the component 12 is greater than the bonding force between the second protective film 15d and the component 12, during the process of removing (tearing off) the second protective film 15d in step S122g, the component 12 and the second substrate 15a remain bonded.

[0145] In some embodiments, in the first substrate 11 , the distance between the centers of any two adjacent grooves 111 is a preset distance.

[0146] Correspondingly, in order to ensure that the groove 111 on the first substrate 11 and the component 12 on the second substrate 15 are well aligned in step S124, step S122g includes the following steps:

[0147] The second protective film 15 d is removed to transfer the components 12 onto the second substrate 15 a , and the second substrate 15 a is stretched until the distance between the centers of any two adjacent components 12 on the second substrate 15 a reaches the above-mentioned preset distance, thereby forming the second substrate 15 .

[0148] Correspondingly, in order to reduce the difficulty of stretching the second substrate 15a, the material of the second substrate 15a may be a flexible material, such as polyvinyl chloride (PVC).

[0149] It can be understood that, since the first pad of the component 12 is bonded to the second substrate 15 a , the stretching of the second substrate 15 a can increase the distance (Pitch) between the centers of two adjacent components 12 .

[0150] In some embodiments, the stretching of the second substrate 15a can be completed by a wafer expander.

[0151] Therefore, in the present application, the first substrate 11 and the second substrate 15 are used in combination to further transform the small pitch transfer problem of the component 12 (miniLED or micro LED) into a large pitch transfer, thereby reducing the precision requirements of the component 12. Therefore, there is no need to use expensive high-precision equipment, which reduces the cost and also reduces the difficulty of transfer.

[0152] In some embodiments, the preset distance is 100 μm.

[0153] In some embodiments, a side of the driving substrate 14 for carrying the components 12 is provided with a plurality of groups of second pads 141 corresponding to the first pads of each component 12 .

[0154] In some embodiments, the upper surface of the second pad 141 of the driving substrate 14 is flush with the upper surface of the base substrate 142 .

[0155] Correspondingly, after step S140, the above preparation method further includes the following steps:

[0156] Step S150: tilting the driving substrate 14 so that each component 12 covered by the protective layer 13 on the driving substrate 14 slides respectively until its first pad contacts the corresponding second pad 141;

[0157] Step S160 : connecting the first pad of each component 12 to the corresponding second pad 141 .

[0158] In some embodiments, in step S160, the method of connecting the first pad and the second pad 141 of the component 12 includes reflow soldering.

[0159] In some embodiments, in step S150, when the first pads of the components 12 covered by the protective layer 13 on the driving substrate 14 contact the corresponding second pads 141, any two adjacent components 12 covered by the protective layer 13 contact each other. Fig.18 shown.

[0160] It can be understood that, for the components 12 arranged in an array, when the components 12 covered by the protective layer 13 are in contact with each other, as long as the array edge of the components 12 is at the corresponding position (corresponding target area), the corresponding components 12 will also be at the corresponding position (corresponding target position). In other words, by tilting the driving substrate 14 multiple times, the components 12 can be aligned with the second pads 141 on the driving substrate 14 while being neatly arranged in the target area. This alignment method greatly reduces the difficulty of aligning the components 12.

[0161] That is to say, when the thickness of the protective layer 13 coated on the side of the component 12 is consistent, when the first pads of each component 12 coated by the protective layer 13 on the driving substrate 14 are in contact with the corresponding second pad 141, the distance (pitch) between the centers of any two adjacent components 12 coated by the protective layer 13 is equal to the groove width of the groove 111 in the first substrate 11. Therefore, the distance (pitch) between the centers of two adjacent components 12 on the final display panel can be adjusted by adjusting the groove width of the groove 111 in the first substrate 11 according to different design requirements.

[0162] In the step of tilting the driving substrate 14 in step S150 , the component 12 does not leave the driving substrate 14 .

[0163] When the component 12 does not leave the driving substrate 14, the inclination angle of the driving substrate 14 can be calculated by the following method: First, the component 12 is pulled on the driving substrate 14 to move at a constant speed by a tensile gauge and the degree F of the tensile gauge is read. 拉力计读数 , assuming that the current tilt angle of the driving substrate 14 is θ, at this time, the friction force f on the driving substrate 14 is f = F 拉力计读数 -mg sinθ, according to the force analysis, we can get f / μ=mg cosθ, and the two equations can be combined to get:

[0164]

[0165] Wherein, m is the mass of the component 12 , g is the acceleration of gravity, and μ is the friction coefficient of the component 12 on the driving substrate 14 .

[0166] In some embodiments, the structure of the driving substrate 14 used in the present application is as follows: Fig.19 As shown, the driving substrate 14 includes a base substrate 142 and a movable baffle 143 disposed on the base substrate 142 .

[0167] The base substrate 142 includes a display area (not marked in the figure), and the display area is provided with a plurality of groups of second pads 141 corresponding to the first pads of the component 12 .

[0168] The movable baffle 143 is disposed around the display area, and is used to move on the base substrate 142 in a direction perpendicular to the baffle 143 as the base substrate 142 tilts. The vertical baffle 143 can move in the horizontal direction, and the horizontal baffle 143 can move in the vertical direction.

[0169] During the tilting process of the driving substrate 14 with such a structure, the blocking effect of the baffles 143 around the display area can be utilized to arrange the components 12 neatly in the display area and align them with the second pads 141 on the driving substrate 14 .

[0170] In some embodiments, the base substrate 142 is provided with slide rails 144 around the display area, and the baffle 143 is provided with a universal roller 143a on one side close to the base substrate 142, which is used to slide in the slide rail 144 perpendicular to the baffle 143. The universal roller 143a of the vertical baffle 143 moves in the horizontal slide rail 144, and the universal roller 143a of the horizontal baffle 143 moves in the vertical slide rail 144.

[0171] In some embodiments, baffle 143 is removable.

[0172] like Fig. 20 As shown, during the process of tilting the driving substrate 14 in the "left, right, up, and down" directions, the friction between the driving substrate 14 and the components 12, as well as the action and reaction between the baffle 143 and the components 12, can be used to make the components 12 arranged neatly (and in contact with each other). When the components 12 are arranged neatly and the baffle 143 is placed in the designed final position (the final position is confirmed by the Mark point), at this time, the corresponding components 12 will also be at the corresponding position (the corresponding target position), and its first soldering pad will contact the corresponding second soldering pad 141. At this moment, the position of the baffle 143 is fixed by a fixture. Subsequently, the first soldering pad and the second soldering pad 141 of the component 12 are connected. After the connection is completed, the baffle 143 can be removed and the slide rail 144 can be cut off.

[0173] In some embodiments, the component 12 may also be a driver chip, such as a driver IC chip. It can be understood that the transfer method of the component 12 in the preparation method provided in the present application is also applicable to the transfer technology of the driver IC chip.

[0174] The method for preparing a display panel provided in an embodiment of the present application comprises the following steps: accommodating a component 12 in a groove 111 of a first substrate 11, and then filling the groove 111 with a protective layer 13 so that the protective layer 13 covers the component 12, thereby increasing the overall volume of the component 12 (the overall volume of the component 12 covered by the protective layer 13); and then transferring the component 12 covered by the protective layer 13 to a driving substrate 14, thereby converting the problem of transferring a large amount of small-sized and high-density components 12 into a problem of transferring a large amount of large-sized and low-density components, thereby greatly reducing the difficulty of transferring the component 12, improving the transfer efficiency of the component 12, and improving the yield of the display panel.

[0175] An embodiment of the present application also provides a display panel, which is prepared by any of the above-mentioned preparation methods, and the display panel includes a driving substrate 14 and a plurality of components 12 arranged on the driving substrate 14; wherein a first solder pad is provided on a side of the component 12 close to the driving substrate 14, the component 12 is at least partially covered by a protective layer 13, and the protective layer 13 does not cover the side of the first solder pad of the component 12 close to the driving substrate 14.

[0176] In some embodiments, a plurality of groups of second pads 141 are disposed on a side of the driving substrate 14 close to the component 12 ; the first pad of each component 12 is electrically connected to the corresponding second pad 141 .

[0177] Correspondingly, any two adjacent components 12 covered by the protection layer 13 are in contact with each other.

[0178] That is to say, in the display panel manufactured by the above manufacturing method, any two adjacent components 12 are isolated by the protective layer 13 .

[0179] An embodiment of the present application further provides a display device, which includes any one of the display panels described above.

[0180] In some embodiments, the display device further comprises a housing. The display panel is connected to the housing, for example, the display panel is embedded in the housing. The display device can be, for example, a mobile phone, a tablet computer, a television, a laptop computer, a digital photo frame, a navigator, or any other device having a display function.

[0181] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application. Although the implementation methods disclosed in the present application are as above, the content is only an implementation method adopted to facilitate the understanding of the present application and is not intended to limit the present application. Any technician in the technical field to which the present application belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present application, but the protection scope of the present application shall still be subject to the scope defined by the attached claims.

Claims

1. A method for preparing a display panel, characterized in that: include: A first substrate is provided; wherein a plurality of grooves are arranged on the first substrate; and in the first substrate, inner surfaces of the grooves are covered with a chrome-plated metal layer; Accommodating a plurality of components in the plurality of grooves of the first substrate to form a transfer substrate; wherein a first pad is disposed on a side of the component away from the bottom of the groove; Filling a protective layer in the groove of the transfer substrate so that the component in the groove is at least partially covered by the protective layer; wherein the protective layer does not cover the side of the first pad of the component away from the bottom of the groove, and the material of the protective layer includes silicone; A driving substrate is provided, the driving substrate is aligned with the side where the first pad of the component is located, and the first substrate is removed to transfer the component covered by the protective layer to the driving substrate.

2. The preparation method according to claim 1, characterized in that: In the transfer substrate, the orthographic projection of the component on the first substrate is located within the orthographic projection range of the groove on the first substrate, and the component does not contact the side wall of the groove.

3. The preparation method according to claim 2, characterized in that: The step of filling the groove of the transfer substrate with a protective layer comprises the following steps: A protective layer is filled in the groove of the transfer substrate, so that the protective layer at least partially fills the gap between the component and the side wall of the groove.

4. The preparation method according to claim 1, characterized in that: In the first substrate, the connection between the side wall and the bottom of the groove is provided with an inclined chamfer, an arc chamfer or a right angle.

5. The preparation method according to claim 1, characterized in that: A side of the driving substrate for carrying the components is provided with a plurality of groups of second pads corresponding to the first pads of each component; the method further includes: Tilt the driving substrate so that each of the components on the driving substrate covered by the protective layer slides respectively until the first pads thereof contact the corresponding second pads; Connect the first pad of each component to the corresponding second pad.

6. The preparation method according to claim 5, characterized in that: When the first pads of the components covered by the protective layer on the driving substrate are in contact with the corresponding second pads, any two adjacent components covered by the protective layer are in contact with each other.

7. The preparation method according to claim 5, characterized in that: In the step of tilting the driving substrate, the components do not leave the driving substrate.

8. The preparation method according to claim 1, characterized in that: The protection layer does not cover a surface of the first substrate that is opposite to the driving substrate.

9. The preparation method according to claim 1, characterized in that: The components include light emitting devices; The first pads of the component include an anode pad and a cathode pad that are spaced apart from each other, wherein in the transfer substrate, the orthographic projections of the anode pad and the cathode pad on the first substrate have different shapes.

10. The preparation method according to claim 9, characterized in that: The protection layer is also filled in the gap between the anode pad and the cathode pad.

11. The preparation method according to claim 1, characterized in that: Accommodating a plurality of components in the plurality of grooves of the first substrate to form a transfer substrate comprises the following steps: Providing a second substrate; wherein the second substrate comprises a second base and the plurality of components disposed on the second base, and the first pads of the components are bonded to the second base; The second substrate is aligned with the first substrate so that the components are embedded in the groove of the first substrate, and the second base is removed to transfer the components to the groove of the first substrate, thereby forming the transfer substrate.

12. The preparation method according to claim 11, characterized in that: In the second substrate, the first pad of the component is bonded to the second base through a photosensitive adhesive layer; Before the step of removing the second substrate, the method further comprises: The photosensitive adhesive layer is irradiated with light of a preset wavelength to reduce the viscosity of the photosensitive adhesive layer, so that the second substrate is separated from the first pad of the component.

13. The preparation method according to claim 11, characterized in that: The second substrate is prepared by the following steps: Providing a third substrate, and forming the plurality of components on the third substrate; wherein the first pads of the components are located on a side of the components away from the third substrate; Providing a first protective film, and aligning the first protective film with the third substrate so that the first protective film is bonded to the first pad of the component; removing the third substrate to transfer the components to the first protective film; Providing a second protective film, and aligning the second protective film with the first protective film so that the second protective film is bonded to a side of the component away from the first protective film; wherein the bonding force between the second protective film and the component is greater than the bonding force between the first protective film and the component; removing the first protective film to transfer the components to the second protective film; Providing the second substrate, and aligning the second substrate with the second protective film so that the second substrate is bonded to the first pad of the component; wherein the bonding force between the second substrate and the component is greater than the bonding force between the second protective film and the component; The second protective film is removed to transfer the components to the second base, thereby forming the second substrate.

14. The preparation method according to claim 13, characterized in that: In the first substrate, the distance between the centers of any two adjacent grooves is a preset distance; Removing the second protective film to transfer the plurality of components to the second base, thereby forming the second substrate, comprises the following steps: The second protective film is removed to transfer the components to the second substrate, and the second substrate is stretched until the distance between the centers of any two adjacent components on the second substrate reaches the preset distance, thereby forming the second substrate.

15. A display panel manufactured by the manufacturing method according to any one of claims 1 to 14, characterized in that: It includes a driving substrate and a plurality of components arranged on the driving substrate; A first pad is disposed on a side of the component close to the drive substrate, the component is at least partially covered by a protective layer, and the protective layer does not cover the side of the first pad of the component close to the drive substrate.

16. The display panel according to claim 15, characterized in that: A plurality of groups of second pads are arranged on one side of the driving substrate close to the components; The first pad of each of the components is electrically connected to the corresponding second pad.

17. The display panel according to claim 16, characterized in that: Any two adjacent components covered by the protective layer are in contact with each other.

18. A display device, characterized in that: Comprising the display panel as claimed in any one of claims 15 to 17.

Images