Display panel, preparation method thereof and display device

Abstract

The invention provides a display panel, a preparation method thereof and a display device, and relates to the technical field of display, and the preparation method of the display panel comprises the following steps: providing a substrate; wherein the substrate comprises a front face, a back face and side faces, the front face and the back face are oppositely arranged, and the front face is connected with the back face through the side faces; forming a plurality of light-emitting elements arranged in an array on the front surface; forming a packaging layer on one side, deviating from the substrate, of the light-emitting element; wherein the packaging layer covers the light-emitting element and a part of the front surface; forming side edge wires on the side surfaces; forming a side protection layer on one side, deviating from the substrate, of the side line; wherein the side edge protection layer wraps the side edge wires, and the side edge protection layer is in contact with the packaging layer; wherein the packaging layer does not cover the side wires and the side protection layers. According to the display panel, the reliability risk of the side wiring under high temperature and high humidity can be improved, the problem of detection and repair is solved, the yield of the side wiring is improved, and the display effect, reliability and other performance of the display panel are improved.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a display panel, a method for manufacturing the same, and a display device. Background Technology

[0002] Display panels made of micro light-emitting diodes (Micro LED, also known as micro LED or μLED) are considered to be the next generation of display technology with development potential due to their advantages such as thinness, flexibility, drop resistance, foldability, long lifespan, ultra-low power consumption, high response speed and high transparency.

[0003] To achieve seamless "wireless splicing" of μLEDs, a side-wiring process has been developed. Current methods for implementing side-wiring include three-dimensional printing (3D) conductive paste, laser etching, and dry film photoresist (DFR). However, these methods cannot accurately detect side-wiring, making repair difficult or leading to problems being discovered only after the display panel is finished, resulting in scrapped panels. This is costly and detrimental to industrial production and application. Summary of the Invention

[0004] This application provides a display panel and its manufacturing method and display device. The display panel can improve the reliability risk of side traces in high temperature and high humidity environments and solve the problems of detection and repair, thereby improving the yield of side traces and thus improving the display effect and reliability of the display panel, which is beneficial to industrial production and application.

[0005] In a first aspect, a method for manufacturing a display panel is provided, comprising the following steps: A substrate is provided; wherein the substrate includes a front side, a back side, and a side side, the front side and the back side are disposed opposite to each other, and the front side is connected to the back side through the side side. Multiple light-emitting elements are arranged in an array on the front side; An encapsulation layer is formed on the side of the light-emitting element away from the substrate; wherein the encapsulation layer covers the light-emitting element and part of the front side; Use conductive paste to form side traces on the side; A side protection layer is formed on the side of the side trace that is away from the substrate; wherein the side protection layer covers the side trace and is in contact with the encapsulation layer. The encapsulation layer does not cover the side traces or the side protection layer.

[0006] Because the above technical solution involves die bonding first and then forming the side traces, it allows for real-time detection of the light-emitting elements after die bonding and real-time detection of the side traces after formation. This solves the industry-wide problem of side trace detection, improves the yield of side traces, and avoids the reliability degradation of side traces caused by die bonding and reflow soldering. It also improves the reliability risk of side traces in high-temperature and high-humidity environments, solves the detection and repair problems, significantly improves the yield of side traces, and thus improves the display effect and reliability of the display panel. Furthermore, it enables better seamless splicing of large screens, which is beneficial for industrial production and application.

[0007] In some embodiments, after forming a plurality of light-emitting elements arranged in an array on the front side and before forming an encapsulation layer on the side of the light-emitting elements facing away from the substrate, the fabrication method further includes: The light-emitting elements are inspected, and if any abnormalities are detected, the abnormal light-emitting elements are repaired. After forming side traces on the side using conductive paste, and before forming a side protective layer on the side of the side traces away from the substrate, the fabrication method further includes: Inspect the side wiring; if any abnormalities are detected, repair the abnormal side wiring. In the above technical solution, die bonding and real-time detection are performed first, followed by the formation of side traces and real-time detection. This not only avoids the risks of false detection and missed detection, improves the efficiency and yield of side trace repair, and reduces the detection cost of the entire process, but also avoids the reliability degradation of side traces caused by die bonding and reflow soldering. It can improve the reliability risk of side traces in high temperature and high humidity environments, solve the detection and repair problems, and significantly improve the yield of side traces. This, in turn, improves the display effect and reliability of the display panel, and can better realize seamless splicing display of large screens, which is beneficial to industrial production and application.

[0008] In some embodiments, the plurality of light-emitting elements arranged in an array on the front side include: Multiple light-emitting elements are arranged in an array on the front side, and trace overlap structures are formed on the front and back sides. The trace overlap structures on the front side are separate from and spaced apart from the light-emitting elements. The trace overlap structures on the front side are located between the light-emitting elements and the side traces. The trace overlap structures on the front side are in direct contact with the encapsulation layer and the side traces, respectively. The encapsulation layer does not cover the trace overlap structures on the front side. The side protective layer also covers the trace overlap structures. In the above technical solution, by ensuring that the encapsulation layer does not cover the wiring overlap structure during preparation, the reliability risk of side wiring in high temperature and high humidity environments can be improved, and the problems of detection and repair can be solved, thereby significantly improving the yield of side wiring. At the same time, the side protective layer covers the wiring overlap structure, effectively protecting the wiring overlap structure, thereby improving the display effect and reliability of the display panel, and enabling better seamless splicing display of large screens, which is beneficial to industrial production and application.

[0009] Secondly, a display panel is provided, comprising: The substrate includes a front side, a back side, and a side side, with the front side and the back side facing each other, and the front side being connected to the back side via the side side. Multiple light-emitting elements are arranged in an array, with the light-emitting elements positioned on the front. Side routing is located on the side, and the material of the side routing is conductive paste; Side protective layer, the side protective layer covers the side wiring; The encapsulation layer is in contact with the side protection layer and covers the light-emitting element and part of the front side, but does not cover the side traces or the side protection layer.

[0010] Because the above technical solution can improve the reliability risk of side wiring in high temperature and high humidity environments and solve the problems of detection and repair, it can significantly improve the yield of side wiring, thereby improving the display effect and reliability of the display panel, and can better realize seamless splicing display of large screens, which is conducive to industrial production and application.

[0011] In some embodiments, the display panel includes a display panel prepared by the method described above.

[0012] The above technical solution can improve the reliability risk of side wiring in high temperature and high humidity environments and solve the problems of detection and repair, thereby significantly improving the yield of side wiring, which in turn improves the display effect and reliability of the display panel, and can better realize seamless splicing display of large screens, which is beneficial to industrial production and application.

[0013] In some embodiments, the display panel further includes: a wiring overlap structure, the wiring overlap structure being disposed on the front and back sides, the wiring overlap structure on the front side being separate from and spaced apart from the light-emitting element, the wiring overlap structure on the front side being located between the light-emitting element and the side wiring, and the wiring overlap structure on the front side being in direct contact with the encapsulation layer and the side wiring respectively. The encapsulation layer does not cover the trace overlap structure on the front side; The side protective layer also covers the wiring overlap structure. In the above technical solution, by not covering the wiring overlap structure with the encapsulation layer, the reliability risk of side wiring in high temperature and high humidity environments can be improved, and the problems of detection and repair can be solved, thereby significantly improving the yield of side wiring. At the same time, the side protective layer covers the wiring overlap structure, effectively protecting the wiring overlap structure, thereby improving the display effect and reliability of the display panel, and enabling better seamless splicing display of large screens, which is beneficial to industrial production and application.

[0014] In some embodiments, the side protective layer is in direct contact with the encapsulation layer along the first direction, and the side protective layer also extends along the first direction to the surface of the encapsulation layer on the side away from the substrate, and covers part of the encapsulation layer but does not cover the light-emitting element. The first direction is the direction perpendicular to the thickness direction of the substrate. In the above technical solution, by extending the side protective layer along the first direction to the surface of the encapsulation layer away from the substrate, covering part of the encapsulation layer but not covering the light-emitting element, it is possible to ensure as much as possible that the light emission effect of the display panel is not affected.

[0015] In some embodiments, the difference between the height of the portion of the side protection layer extending along the first direction to the surface of the encapsulation layer on the side opposite to the substrate and the height of the encapsulation layer along the second direction is 25 μm-30 μm. The second direction is parallel to the thickness direction of the substrate. The above technical solution enables the substrate to be covered as much as possible by the encapsulation layer and the side protection layer, and is easy to manufacture.

[0016] In some embodiments, the height of the entire side protective layer along the second direction is 50μm-100μm; The second direction is parallel to the thickness direction of the substrate. In the above technical solution, the side protective layer can achieve a high film thickness, thereby improving the oxidation resistance of the side traces (blocking water and oxygen) and improving problems such as abnormal crystal bonding caused by discontinuity in the area where the side traces are located.

[0017] In some embodiments, the optical density of the encapsulation layer is 0.5-1; And / or, the optical density of the side protective layer is greater than or equal to 3. In the above technical solution, the encapsulation layer has the effect of not completely blocking light, filtering only some stray light, while ensuring the transparency of the display panel's own light emission, so that the front display area is well protected by the encapsulation layer and achieves light transmission balance, ensuring that the picture can be transmitted normally without being interfered with by too much stray light; while the side protective layer has strong light blocking and is nearly opaque, responsible for strong light blocking and protection of the non-display areas of the display panel, in order to improve edge light leakage, stray light intrusion and appearance problems. Thus, the two work together to enable the display panel to achieve clear and transparent display, no edge light leakage, and a clean appearance.

[0018] Thirdly, a display device is provided, comprising a display panel prepared by the method described above or a display panel prepared as described above.

[0019] Because the above technical solution can improve the reliability risk of side traces in display devices under high temperature and high humidity environments and solve the problems of detection and repair, the yield of side traces can be greatly improved, thereby improving the display effect and reliability of the display device. The overall performance of the display device is better, and it is also conducive to industrial production and application. Attached Figure Description

[0020] Figure 1 A process flow diagram of the manufacturing process of a display panel provided by related technologies is shown; Figure 2 A schematic diagram of the structure of a display panel provided by related technologies is shown; Figure 3 A process flow diagram of the manufacturing process of a display panel provided in some embodiments of this application is shown; Figure 4 A process flow diagram of the manufacturing process of a display panel provided in some embodiments of this application is shown; Figure 5 A schematic diagram of the structure of a display panel provided in some embodiments of this application is shown. Detailed Implementation

[0021] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application. In the description of the embodiments of this application, the term "at least one" refers to one or more, and "more than one" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be a single item or multiple items. It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on the other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to the other component. In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances. It should be understood that "electrical connection" in the embodiments of this application can be understood as physical contact and electrical conduction between components, or as the form of connection between different components in the circuit structure through a physical line that can transmit electrical signals. In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0022] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0023] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments in any suitable manner.

[0024] μLED's advantages lie in its high brightness, wide color gamut, high reliability, ease of achieving flexibility, transparency, free splicing, and sensor integration. This allows it to be widely researched and applied across multiple fields, from micro-displays to consumer electronics and large-screen displays, making it widely recognized as a next-generation display technology with great development potential. Among these, "wireless splicing" is considered a key industrialization goal for μLED display technology. Specifically, "wireless splicing" refers to combining many individual display panels into a single ultra-large display device. This process eliminates the need for traditional wired connections such as network cables and data cables, enabling data synchronization and collaborative display between display panels through wireless transmission. This is a unique advantage of μLED display technology, something that traditional Liquid Crystal Display (LCD) and Organic Light Emitting Diode (OLED) displays cannot achieve.

[0025] To achieve "wireless splicing" of μLEDs, a side-wiring process was developed. Side-wiring refers to creating specific structures on the front and back sides of the substrate (the front and back sides are set opposite each other). After connecting to the structure on the front side through wiring, the wiring bends from the side of the substrate to the back side and connects to the structure on the back side. In other words, conductive wiring is formed on the side of the substrate (i.e., the side edge), so that the electrical connection between the structure on the front side and the structure on the back side can be achieved through the side-wiring.

[0026] Traditional side traces are generally obtained through three methods: First, using 3D printing of conductive paste, patterned traces can be directly printed on the side of the substrate where traces are needed, eliminating the need for full-surface coating and patterning. This results in high material utilization, user-friendly processing, and low cost. However, it has been found that the generated side traces have high resistance that is difficult to reduce, leading to low yields for both side traces and die bonding, and significant reliability risks. To address these issues, processes such as laser etching and DFR (Device Frame Recognition) have emerged. The second method, laser etching, involves coating the entire surface of the substrate using Physical Vapor Deposition (PVD) and then etching the traces using a laser. This method offers advantages such as one-step formation of traces on both the side and back sides of the substrate, high precision, good uniformity, and a large process window. However, the disadvantages include the waste caused by laser etching after full-surface coating, and the low material utilization, high equipment investment costs, and low efficiency due to the lack of breakthroughs in back-side trace engraving technology. The third type, DFR, involves depositing a dry film over the entire substrate surface using PVD, followed by patterned traces. This approach allows for one-step formation of traces on the sides and back of the substrate, eliminating the need for separate back-side etching. However, it suffers from low material utilization, high process complexity, and the potential for dry film photoresist outgassing (DFR Outgas), which can negatively impact the PVD coating. Furthermore, both laser etching and DFR involve packaging the LED chip after mounting it. Performing these operations in a vacuum chamber can lead to bubbling and other defects. Therefore, methods such as forming side traces before die bonding and packaging, or die bonding and packaging before forming side traces, are unsuitable for laser etching and DFR.

[0027] With the development of technology, research has found that the process of forming side traces in 3D printing conductive paste can be optimized to improve the results. Therefore, further research and practical applications are being explored. As is well known, to save costs, in actual mass production, panel manufacturers typically provide substrates with pre-formed side traces. These panel manufacturers then sell these substrates to back-end manufacturers, who can directly perform die bonding and other processes to manufacture the product. Thus, the basic process route in related technologies is to first form the side traces, and then perform die bonding. Figure 1 This illustrates a fabrication process provided by related technologies, which involves first forming side traces and then die bonding. For example... Figure 1 As shown in Figure (a), solder joints 2 are formed on the front side of substrate 1, and trace overlap structure 3 is formed on one side of substrate 1; Figure 1 As shown in Figure (b), a side trace 6 is formed on the side of the partial trace overlap structure 3 facing away from the substrate 1; as Figure 1As shown in Figure (c), the side traces 6 are inspected. If one or more side traces 6 are found to be defective, the defective side traces 6 are repaired. Figure 1 As shown in Figure (d), a side protective layer 7 is formed to cover the overlapping structure 3 of the wiring and the side wiring 6; as shown in Figure (d), Figure 1 As shown in Figure (e), die bonding is performed on the side of solder joint 2 away from substrate 1, thus forming an LED of at least one color; as shown in Figure (e), Figure 1 As shown in Figure (f), a lighting test is performed. If one or more LEDs are found to be non-emitting, the non-emitting LEDs are repaired. Figure 1 As shown in Figure (g), an encapsulation layer 5 is formed covering solder joint 2, red LED 41, green LED 42, blue LED 43, part of the front side of substrate 1, trace overlap structure 3, and side trace 6, resulting in... Figure 2 The display panel shown. It should be noted that... Figure 1 In Figure (b), there is a wiring overlap structure 3 on which a side wiring 6 is not formed. This is to illustrate that the wiring overlap structure 3 does not form an effective side wiring 6 and needs to be repaired.

[0028] Figure 1 In Figure (c), when inspecting the side trace 6, the LED is not directly lit for visual judgment. Given the large number of side traces 6 currently available, in actual production and manufacturing processes, to meet mass production requirements, dense side traces 6 are usually inspected through large-area inspections. This often leads to missed or false detections; for example, small-area defects are difficult to detect. Furthermore, even if this step detects no problems with the side trace 6, it may still oxidize and agglomerate to form high resistance in subsequent processes, such as during die bonding and reflow soldering. At the same time, the conductive paste forming the side trace 6 is relatively soft, and the overlapping solder joints are easily damaged during inspection, resulting in performance degradation of the side trace 6. Discontinuity in the side trace 6 can lead to die bonding abnormalities, which in turn cause display abnormalities, such as bright and dark lines. Moreover, these abnormalities are difficult to repair, so they are likely to be scrapped due to excessive costs.

[0029] Therefore, there is an urgent need to provide a novel method for preparing a display panel and the resulting display panel to solve the above problems.

[0030] Based on the above, the embodiments of this application do not impose any restrictions on the specific types of display panels and display devices using them. Display panels can have various implementation methods, such as including but not limited to televisions, augmented reality (AR) glasses, virtual reality (VR) glasses, projectors, head-up displays (HUDs), digital car lights, or embedded image displays.

[0031] To facilitate a further understanding of the technical solutions in some embodiments of this application, the technical solutions of the display panel and its manufacturing method, the display device, and how these technical solutions solve the aforementioned technical problems are described in detail below with reference to specific embodiments and accompanying drawings. Each embodiment can be combined with others, and the same or similar concepts or processes may not be repeated in some embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments.

[0032] This application provides a method for manufacturing a display panel, such as... Figure 3 and Figure 4 As shown, the method for manufacturing the display panel in this embodiment may include the following steps: S1. Provide substrate 1.

[0033] S2, Multiple light-emitting elements 4 are arranged in an array on the front side 11.

[0034] S3. An encapsulation layer 5 is formed on the side of the light-emitting element 4 that is away from the substrate 1.

[0035] S4. Use conductive paste to form side traces 6 on the side 13.

[0036] S5. A side protective layer 7 is formed on the side of the side trace 6 away from the substrate 1 to obtain a display panel.

[0037] The substrate 1 includes a front side 11, a back side 12, and a side side 13. The front side 11 and the back side 12 are disposed opposite to each other, and the front side 11 is connected to the back side 12 through the side side 13. The encapsulation layer 5 covers the light-emitting element 4 and part of the front side 11. The side protection layer 7 covers the side traces 6 and is in contact with the encapsulation layer 5. The encapsulation layer 5 does not cover the side traces 6 and the side protection layer 7.

[0038] In addition, since the side protective layer 7 is completed in the last process, it can achieve a high film thickness, improve the oxidation resistance of the side trace 6 (block water and oxygen), and improve problems such as abnormal crystal bonding caused by discontinuity in the area where the side trace 6 is located.

[0039] In practical applications, the aforementioned display panel can be an active-drive display panel, i.e., a self-driving display panel, such as μLED, Mini LED, or other active-drive display panels. The substrate 1 can be a glass substrate, etc.

[0040] As an example, the display panel in this application embodiment can be a glass-based μLED splicing display panel.

[0041] The light-emitting element 4 in this embodiment may include a red LED 41, a green LED 42, and a blue LED 43. The red LED 41 is connected to a solder joint 2, the green LED 42 is connected to a solder joint 2, and the blue LED 43 is connected to a solder joint 2. Of course, it is not limited to this, and the specific application shall prevail.

[0042] In practical implementation, a low-temperature polycrystalline silicon (LTPS) backplane can be used in conjunction with a driver integrated circuit (IC). Unlike traditional amorphous silicon (a-Si) backplanes, LTPS backplanes offer advantages such as high electron mobility, high-resolution driving capability, fast response time, and low power consumption, enabling the display panel to support dynamic switching between dual voltages.

[0043] The material of the aforementioned encapsulation layer can be epoxy resin, acrylic resin, or silicone resin, etc.

[0044] The aforementioned conductive paste may include a paste matrix and conductive particles, with the conductive particles doped into the paste matrix. The paste matrix may be resin, etc., and the conductive particles may include at least one of silver (Ag) particles, copper (Cu) particles, carbon nanotubes (CNTs), or graphite (G). Since Ag has excellent conductivity, silver paste is preferred for fabricating the side traces 6. Furthermore, the side traces 6 formed by 3D printing silver paste can be created using methods such as 3D printing. It should be noted that, while maintaining resistance, Ag and Cu are prone to electromigration, while CNTs and G exhibit less electromigration. Therefore, the type of conductive particles can be selected based on the required display panel and its manufacturing process; no specific limitation is made here, but the actual application shall prevail. Furthermore, the size of the conductive particles can be at the nanometer scale.

[0045] The material of the aforementioned side protection layer 7 can be epoxy resin, acrylic resin, or silicone resin, etc., and the optical density (OD) of the side protection layer 7 material needs to be greater than the OD of the encapsulation layer material. The functions of the side protection layer 7 include: first, protecting the side traces 6 from scratches and damage during subsequent processes; second, providing better water and oxygen barrier properties to enhance the anti-oxidation effect on the side traces 6. Therefore, the side protection layer 7 extends along the second direction ( Figures 3 to 5 The height of the encapsulation layer 5 along the oy direction can be less than, equal to, or greater than the height of the encapsulation layer 5 along the oy direction. The oy direction is parallel to the thickness direction of the substrate 1.

[0046] In specific implementation, the height d1 of the entire side protective layer 7 along the oy direction can be set to 50μm-100μm. For example, d1 can be 50μm, 60μm, 70μm, 80μm, 90μm or 100μm, etc.

[0047] The display panel manufacturing method provided in this application optimizes the process flow by first performing die bonding and then forming side traces. This allows for real-time detection of the light-emitting elements after die bonding and, simultaneously, real-time detection of the side traces after their formation. This solves the industry-wide problem of side trace detection, improves the yield of side traces, and avoids the reliability degradation of side traces caused by die bonding and reflow soldering. It also improves the reliability risk of side traces in high-temperature and high-humidity environments, solves the detection and repair problems, significantly improves the yield of side traces, and thus enhances the display effect and reliability of the display panel. Furthermore, it enables better seamless splicing of large screens, which is beneficial for industrial production and application.

[0048] In some embodiments, after step S2, which involves forming an array of multiple light-emitting elements 4 on the front side 11, and before step S3, which involves forming an encapsulation layer 5 on the side of the light-emitting elements 4 facing away from the substrate 1, the method for manufacturing the display panel provided in this application embodiment may further include the following steps: S6. Inspect the light-emitting element 4. If an abnormality is detected, repair the abnormal light-emitting element 4.

[0049] After step S4 above, where conductive paste is used to form the side trace 6 on the side 13, and before step S5 above, where a side protective layer 7 is formed on the side of the side trace 6 away from the substrate 1, the method for manufacturing the display panel provided in this application embodiment may further include the following steps: S7. Inspect the side wiring 6. If an abnormality is detected, repair the abnormal side wiring 6.

[0050] In actual production and manufacturing processes, it is always unavoidable that some side traces 6 are not connected or not properly connected, and / or the die-bonded light-emitting elements are not properly connected or the LEDs are damaged. Therefore, it is necessary to inspect the light-emitting elements 4 and the side traces 6 separately.

[0051] In practical applications, at least one of Automatic Optical Inspection (AOI) and Open / Short (OS) inspection methods can be used. AOI is a non-contact optical inspection, while OS is a contact electrical inspection; the preferred method is a combination of AOI and OS inspection.

[0052] The display panel manufacturing method provided in this application optimizes the process flow by first performing die bonding and then forming side traces. This allows for real-time detection of the light-emitting elements after die bonding and, simultaneously, real-time detection of the side traces after their formation. This avoids the risks of false detection and missed detection, improves the efficiency and yield of side trace repair, reduces the detection cost of the entire process, and avoids the reliability degradation of side traces caused by die bonding and reflow soldering. It also improves the reliability risk of side traces in high-temperature and high-humidity environments, solves detection and repair problems, significantly improves the yield of side traces, and thus enhances the display effect and reliability of the display panel. Furthermore, it enables better seamless splicing of large screens, which is beneficial for industrial production and application.

[0053] In some embodiments, the method for manufacturing a display panel provided in this application may include the following steps in step S2, which involves forming an array of multiple light-emitting elements 4 on the front side 11: S21, multiple light-emitting elements 4 are arranged in an array on the front side 11, and a wiring overlap structure 3 is formed on the front side 11 and the back side 12.

[0054] In this configuration, the wiring overlap structure 3 on the front side 11 is separate from and spaced apart from the light-emitting element 4. The wiring overlap structure 3 on the front side 11 is located between the light-emitting element 4 and the side wiring 6. The wiring overlap structure 3 on the front side 11 is in direct contact with the encapsulation layer 5 and the side wiring 6 respectively. The encapsulation layer 5 does not cover the wiring overlap structure 3 on the front side 11. The side protective layer 7 also covers the wiring overlap structure 3.

[0055] The display panel manufacturing method provided in this application improves the reliability risk of side traces in high temperature and high humidity environments by ensuring that the encapsulation layer does not cover the trace overlap structure during manufacturing. It also solves the problems of detection and repair, thereby significantly improving the yield of side traces. At the same time, the side protective layer covers the trace overlap structure, effectively protecting it. This improves the display effect and reliability of the display panel and enables better seamless splicing of large screens, which is beneficial for industrial production and application.

[0056] This application embodiment also provides a display panel, such as Figures 3 to 5As shown, the display panel may include: a substrate 1, a plurality of light-emitting elements 4 arranged in an array, side traces 6, a side protective layer 7, and an encapsulation layer 5. The substrate 1 includes a front side 11, a back side 12, and a side side 13. The front side 11 and the back side 12 are disposed opposite to each other. The front side 11 is connected to the back side 12 through the side side 13. The plurality of light-emitting elements 4 arranged in an array are disposed on the front side 11. The side traces 6 are disposed on the side side 13. The material of the side traces 6 is conductive paste. The side protective layer 7 covers the side traces 6. The encapsulation layer 5 is in contact with the side protective layer 7, and the encapsulation layer 5 covers the light-emitting elements 4 and part of the front side 11. The encapsulation layer 5 does not cover the side traces 6 and the side protective layer 7.

[0057] It should be noted that the display panel in this application embodiment can also refer to the above embodiment, and is a display panel prepared by the display panel preparation method of the above embodiment. In addition, the substrate, light-emitting element, side wiring, side protective layer and encapsulation layer in this application embodiment can all refer to the above embodiment, and will not be described again here.

[0058] The display panel provided in this application embodiment, by covering the light-emitting element and part of the front with an encapsulation layer, but not covering the side traces and side protective layer, can improve the reliability risk of the side traces in high temperature and high humidity environments, and solve the problems of detection and repair, thereby greatly improving the yield of the side traces, and thus improving the display effect and reliability of the display panel, and can better realize seamless splicing display of large screens, which is beneficial to industrial production and application.

[0059] In some embodiments, such as Figures 3 to 5 As shown, the display panel provided in this application embodiment may further include: a wiring overlap structure 3, which is disposed on the front side 11 and the back side 12. The wiring overlap structure 3 on the front side 11 is separate from and spaced apart from the light-emitting element 4. The wiring overlap structure 3 on the front side 11 is located between the light-emitting element 4 and the side wiring 6. The wiring overlap structure 3 on the front side 11 is in direct contact with the encapsulation layer 5 and the side wiring 6 respectively. The encapsulation layer 5 does not cover the wiring overlap structure 3 on the front side 11. The side protective layer 7 also covers the wiring overlap structure 3.

[0060] In practical applications, the aforementioned trace overlap structure 3 can be a lapped pad, etc.

[0061] The display panel provided in this application embodiment, by not covering the wiring overlap structure with the encapsulation layer, can improve the reliability risk of side wiring in high temperature and high humidity environments and solve the problems of detection and repair, thereby significantly improving the yield of side wiring. At the same time, the side protective layer covers the wiring overlap structure, effectively protecting the wiring overlap structure, thereby improving the display effect and reliability of the display panel, and better realizing seamless splicing display of large screens, which is beneficial to industrial production and application.

[0062] In some embodiments, such as Figures 3 to 5 As shown, in the display panel provided in this application embodiment, the side protective layer 7 is in direct contact with the encapsulation layer 5 along the first direction, and the side protective layer 7 also extends along the first direction to the surface of the encapsulation layer 5 on the side away from the substrate 1, covering part of the encapsulation layer 5 but not covering the light-emitting element 4.

[0063] Among them, the first direction ( Figure 1 The ox direction in the figure is a direction perpendicular to the thickness direction of the substrate.

[0064] Please refer to the following for practical applications. Figures 3 to 5 The edge of the protective layer 7 on the side of the front 11 is located between the light-emitting element 4 and the wiring overlap structure 3 along the ox direction.

[0065] Please also refer to the following: Figures 3 to 5 In this embodiment, the wiring overlap structure 3 of the display panel and the encapsulation layer 5 do not overlap along the oy direction. The overlap area is the side wiring 6 and the side protective layer 7 from bottom to top along the oy direction. The edge of the encapsulation layer 5 is the encapsulation layer 5 and the side protective layer 7 from bottom to top.

[0066] It should be noted that the front surface 11 of substrate 1 must not be exposed. If a gap is exposed on the front surface 11, the display panel will exhibit display abnormalities. Therefore, in the actual manufacturing process, by ensuring that the side protective layer 7 and the encapsulation layer 5 overlap along the oy direction, it is possible to ensure that the front surface 11 is not exposed as much as possible. However, in the actual manufacturing process, it is usually difficult to ensure that the side protective layer 7 and the encapsulation layer 5 are 100% flush along the ox direction. Therefore, the height of the side protective layer 7 along the oy direction is slightly higher than the height of the encapsulation layer 5 along the oy direction. For example, the difference d2 between the height of the portion of the side protective layer extending along the ox direction to the surface of the encapsulation layer 5 on the side away from substrate 1 and the height of the encapsulation layer 5 along the oy direction is 25μm-30μm. For example, d2 can be 25μm, 26μm, 27μm, 28μm, 29μm, or 30μm, etc., to ensure that the surface of substrate 1 is not exposed and to facilitate manufacturing.

[0067] Furthermore, in this embodiment, the optical density (OD) of the encapsulation layer 5 is 0.5-1, while the OD of the side protective layer 7 is greater than or equal to 3. Preferably, the material of the side protective layer 7 is black. Therefore, when the side protective layer 7 is 100% transparent, the portion of the side protective layer 7 covering the encapsulation layer 5 can extend above the light-emitting element 4. In this case, it has no impact on the light emission effect of the display panel (e.g., light emission efficiency, light emission shape, etc.). However, if the side protective layer 7 is not 100% transparent, the portion of the side protective layer 7 covering the encapsulation layer 5 cannot extend above the light-emitting element 4, ensuring that the light emission effect of the display panel is not affected.

[0068] The display panel provided in this application embodiment extends along the first direction through a side protective layer to the surface of the encapsulation layer opposite to the substrate, covering part of the encapsulation layer but not covering the light-emitting element, which can ensure as much as possible that the light emission effect of the display panel is not affected.

[0069] This application also provides a display device, which may include a display panel as described above or a display panel prepared by the method described above.

[0070] In practical applications, the display device in this embodiment may further include a backlight module. The backlight module is disposed on the backlight side of the display panel and can be used to provide a white light source or a colored light source for the display panel. When the backlight module is used to provide a colored light source for the display panel, it may include red chips, green chips, and blue chips, etc., to achieve a colored light source. Of course, the color of the colored light source in the backlight module is not limited to red, green, or blue; it can be any other color, depending on the actual application.

[0071] Furthermore, the red chip can be an R LED that emits red light, the green chip can be a G LED that emits green light, and the blue chip can be a B LED that emits blue light.

[0072] The display device provided in this application embodiment can improve the reliability risk of side wiring in high temperature and high humidity environments and solve the problems of detection and repair, thereby greatly improving the yield of side wiring, and thus improving the display effect and reliability of the display device. The overall performance of the display device is good, and it is also conducive to industrial production and application.

[0073] This section only introduces some content related to the invention point; other content can be obtained by referring to relevant technologies, and will not be explained in detail here.

[0074] It should be understood that the above description is merely to help those skilled in the art better understand the embodiments of this application, and is not intended to limit the scope of the embodiments of this application. Based on the examples given above, those skilled in the art can obviously make various equivalent modifications or changes. For example, some steps in various embodiments of the method may be optional, or new steps may be added; or any combination of two or more of the above embodiments. Such modifications, changes, or combinations also fall within the scope of the embodiments of this application.

[0075] It should also be understood that the above description of the embodiments of this application focuses on highlighting the differences between the various embodiments. Any similarities or differences not mentioned can be referred to each other. For the sake of brevity, they will not be repeated here.

[0076] It should also be understood that the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0077] It should also be understood that the methods, situations, categories, and classifications of embodiments in this application are for the convenience of description only and should not constitute a special limitation. Various methods, categories, situations, and features in embodiments can be combined without contradiction.

[0078] It should also be understood that, in the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0079] Finally, it should be noted that the above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for manufacturing a display panel, characterized by, The method comprises the following steps: providing a substrate; wherein the substrate comprises a front surface, a back surface and a side surface, the front surface and the back surface are oppositely arranged, and the front surface is connected with the back surface through the side surface; forming a plurality of light emitting elements arranged in an array on the front surface; forming an encapsulation layer on a side of the light emitting elements away from the substrate; wherein the encapsulation layer covers the light emitting elements and part of the front surface; forming a side edge trace on the side surface using conductive paste; forming a side edge protection layer on a side of the side edge trace away from the substrate; wherein the side edge protection layer covers the side edge trace, and the side edge protection layer is in contact with the encapsulation layer; wherein the encapsulation layer does not cover the side edge trace, the side edge protection layer.

2. The method of manufacturing a display panel according to claim 1, wherein After the step of forming a plurality of light emitting elements arranged in an array on the front surface, and before the step of forming an encapsulation layer on a side of the light emitting elements away from the substrate, the method further comprises: detecting the light emitting elements, and if an abnormal light emitting element is detected, repairing the abnormal light emitting element; after the step of forming a side edge trace on the side surface using conductive paste, and before the step of forming a side edge protection layer on a side of the side edge trace away from the substrate, the method further comprises: detecting the side edge trace, and if an abnormal side edge trace is detected, repairing the abnormal side edge trace.

3. The method of producing a display panel according to claim 1 or 2, wherein The step of forming a plurality of light emitting elements arranged in an array on the front surface comprises: forming the plurality of light emitting elements arranged in an array on the front surface, and forming a trace overlap structure on the front surface and the back surface; wherein the trace overlap structure on the front surface is separately and spacedly arranged from the light emitting elements, the trace overlap structure on the front surface is located between the light emitting elements and the side edge trace, the trace overlap structure on the front surface is in direct contact with the encapsulation layer and the side edge trace respectively; the encapsulation layer does not cover the trace overlap structure on the front surface; and the side edge protection layer further covers the trace overlap structure.

4. A display panel, characterized by, comprises: a substrate comprising a front surface, a back surface and a side surface, the front surface and the back surface are oppositely arranged, and the front surface is connected with the back surface through the side surface; a plurality of light emitting elements arranged in an array, the light emitting elements are arranged on the front surface; a side edge trace arranged on the side surface, the material of the side edge trace is conductive paste; a side edge protection layer covering the side edge trace; an encapsulation layer in contact with the side edge protection layer, the encapsulation layer covers the light emitting elements and part of the front surface, and the encapsulation layer does not cover the side edge trace and the side edge protection layer.

5. The display panel of claim 4, wherein, The display panel comprises a display panel prepared by the method for preparing a display panel according to any one of claims 1 to 3.

6. The display panel of claim 4 or 5, wherein, The display panel further comprises a trace overlap structure arranged on the front surface and the back surface, the trace overlap structure on the front surface is separately and spacedly arranged from the light emitting elements, the trace overlap structure on the front surface is located between the light emitting elements and the side edge trace, the trace overlap structure on the front surface is in direct contact with the encapsulation layer and the side edge trace respectively. The encapsulation layer does not cover the wire bonding structure on the front surface; The side protection layer also covers the wire bonding structure.

7. The display panel of claim 4 or 5, wherein, The side protection layer directly contacts the encapsulation layer along a first direction, and the side protection layer extends to the surface of the side of the encapsulation layer away from the substrate along the first direction, covers part of the encapsulation layer, and does not cover the light-emitting element. The first direction is perpendicular to the thickness direction of the substrate.

8. The display panel of claim 4 or 5, wherein, The height of the entire side protection layer along a second direction is 50 μm-100 μm. The height of the part of the side protection layer extending to the surface of the side of the encapsulation layer away from the substrate along the first direction along the second direction is 25 μm-30 μm less than the height of the encapsulation layer along the second direction. The second direction is parallel to the thickness direction of the substrate.

9. The display panel of claim 4 or 5, wherein, The optical density of the encapsulation layer is 0.5-1. The optical density of the side protection layer is greater than or equal to 3.

10. A display device, characterized by comprising: A display panel prepared by the preparation method of the display panel according to any one of claims 1-3 or the display panel according to any one of claims 4-9.

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