Display substrate, preparation method thereof and display device

Abstract

This disclosure provides a display substrate and its fabrication method, as well as a display device, belonging to the field of display technology. It solves the problem that the pixel defining layer in existing display substrates has a strong reflective effect, affecting the display performance. The display substrate of this disclosure includes: a substrate substrate and a pixel defining layer located on the substrate substrate; the pixel defining layer has multiple pixel openings; the pixel defining layer includes: a first inorganic insulating layer, a second inorganic insulating layer, and an organic insulating layer sequentially disposed along a direction away from the substrate substrate; in a direction parallel to the substrate substrate and along the pixel defining layer pointing towards the pixel openings, the edge of the second inorganic insulating layer extends beyond the edges of the first inorganic insulating layer and the organic insulating layer, and multiple micropores are formed on the surface of the second inorganic insulating layer on the side away from the substrate substrate.

Description

Technical Field

[0001] This disclosure belongs to the field of display technology, specifically relating to a display substrate and its preparation method, and a display device. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are advanced light-emitting devices that use organic solid-state semiconductor materials as the organic light-emitting layer. Due to their relatively simple fabrication process, low production cost, excellent power consumption control, high luminous brightness, and wide operating temperature range, OLED technology is widely considered to have broad application prospects in the display and lighting fields.

[0003] In OLED display substrates, the pixel confinement layer primarily defines the light-emitting areas of each sub-pixel, serving as both electrical and physical insulation to prevent color mixing and crosstalk between different color light-emitting materials, thereby ensuring the clarity of the displayed image. However, currently, most commonly used pixel confinement layers are single-layer transparent structures. While this structure has mature manufacturing processes, it exhibits strong reflectivity to ambient light. When ambient light shines on the surface of the display substrate, some of the light is reflected by the pixel confinement layer and enters the user's field of vision. This not only reduces the contrast of the displayed image, making it appear washed out, but also produces noticeable glare in bright light environments, severely interfering with the viewing experience. Summary of the Invention

[0004] This disclosure aims to at least solve one of the technical problems existing in the prior art, and provides a display substrate and its preparation method, as well as a display device.

[0005] In a first aspect, embodiments of this disclosure provide a display substrate, the display substrate comprising: a substrate substrate and a pixel defining layer located on the substrate substrate; the pixel defining layer having a plurality of pixel openings; the pixel defining layer comprising: a first inorganic insulating layer, a second inorganic insulating layer and an organic insulating layer sequentially disposed along a direction away from the substrate substrate;

[0006] In a direction parallel to the substrate and along the pixel defining layer toward the pixel opening, the edge of the second inorganic insulating layer extends beyond the edges of the first inorganic insulating layer and the organic insulating layer, and a plurality of micropores are formed on the surface of the second inorganic insulating layer facing away from the substrate.

[0007] In some embodiments, the display substrate further includes a third inorganic insulating layer located between the second inorganic insulating layer and the organic insulating layer;

[0008] In a direction parallel to the substrate and along the pixel defining layer toward the pixel opening, the edge of the third inorganic insulating layer is flush with the edge of the second inorganic insulating layer.

[0009] In some embodiments, the organic insulating layer is made of a light-absorbing material.

[0010] In some embodiments, the display substrate further includes: a plurality of first electrodes located on the side of the first inorganic insulating layer near the substrate;

[0011] The orthographic projection of the first electrode on the substrate at least partially overlaps with the orthographic projection of the pixel opening on the substrate.

[0012] In some embodiments, the first inorganic insulating layer is filled between adjacent first electrodes.

[0013] In some embodiments, the display substrate further includes: a second electrode located on the side of the first electrode opposite to the substrate, and an organic functional layer located between the first electrode and the second electrode;

[0014] The second electrode is a full-surface electrode; the organic functional layer is formed within the pixel opening and is separated at the edge of the second inorganic insulating layer.

[0015] In some embodiments, the display substrate further includes: a power connection ring surrounding at least a portion of the second electrode; the power connection ring is connected to the second electrode;

[0016] At the junction of the power supply overlap ring and the second electrode, the edge of the organic insulating layer extends beyond the edges of the first inorganic insulating layer and the second inorganic insulating layer.

[0017] In some embodiments, the display substrate further includes: a plurality of power signal terminals located on the substrate;

[0018] Multiple power signal terminals are connected to the power connection ring.

[0019] In some embodiments, the display substrate further includes: a plurality of data signal lines located on the side of the first electrode near the substrate; each of the data signal lines is connected to the first electrode in a sub-pixel of the same color in the same column;

[0020] The display substrate further includes: multiple adapter lines and multiple data signal terminals located between the data signal lines and the first electrode; each data signal terminal is connected to multiple data signal lines connected to the first electrode in multiple columns of sub-pixels of the same color through one adapter line.

[0021] Secondly, embodiments of this disclosure provide a display device, the display device including a display substrate as provided in the first aspect.

[0022] In some embodiments, the display device further includes: an encapsulation layer located on the side of the second electrode facing away from the substrate, a black matrix layer located on the side of the encapsulation layer facing away from the substrate, and a color filter layer;

[0023] The black matrix layer has multiple light-transmitting openings; the orthographic projection of the light-transmitting openings on the substrate at least partially overlaps with the orthographic projection of the pixel openings on the substrate.

[0024] The color filter layer includes multiple color filters; the color filters are disposed within the light-transmitting opening.

[0025] Thirdly, embodiments of this disclosure provide a method for preparing a display substrate, the method comprising:

[0026] A first inorganic insulating layer and a second inorganic insulating layer are sequentially formed on the substrate.

[0027] Using patterning techniques, the first inorganic insulating layer and the second inorganic insulating layer are patterned to form pixel openings;

[0028] The surface of the second inorganic insulating layer on the side away from the substrate is roughened to form multiple micropores;

[0029] An organic insulating layer is formed on the side of the second inorganic insulating layer away from the substrate; in a direction parallel to the substrate and along the pixel defining layer toward the pixel opening, the edge of the second inorganic insulating layer extends beyond the edges of the first inorganic insulating layer and the organic insulating layer.

[0030] In some embodiments, the process of forming an organic insulating layer on the side of the second inorganic insulating layer away from the substrate further includes:

[0031] A third inorganic insulating layer is formed on the side of the second inorganic insulating layer away from the substrate; the edge of the third inorganic insulating layer is flush with the edge of the second inorganic insulating layer in a direction parallel to the substrate and along the pixel defining layer toward the pixel opening. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of an exemplary display substrate.

[0033] Figure 2 This is a schematic diagram of the structure of a display substrate provided in an embodiment of this disclosure.

[0034] Figure 3 This is a schematic diagram of another display substrate provided in an embodiment of the present disclosure.

[0035] Figure 4 This is a schematic diagram of the structure of another display substrate provided in an embodiment of the present disclosure.

[0036] Figure 5 This is a schematic diagram of a planar structure of a display substrate provided in an embodiment of the present disclosure.

[0037] Figure 6 This is a schematic diagram of the structure of a display device provided in an embodiment of the present disclosure.

[0038] Figure 7 This is a schematic flowchart illustrating a method for fabricating a display substrate according to an embodiment of the present disclosure. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. The components of the embodiments of this disclosure described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this disclosure provided in the accompanying drawings is not intended to limit the scope of the claimed disclosure, but merely represents selected embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure. Without conflict, the various embodiments of this disclosure and the features in the embodiments can be combined with each other.

[0040] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising,” “including,” or “including,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects.

[0041] In this disclosure, "multiple or several" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0042] Figure 1 This is a schematic diagram of an exemplary display substrate, such as... Figure 1 As shown, the display substrate includes: a substrate 101, and a pixel defining layer 102 located on the substrate 101. The pixel defining layer 102 has a plurality of pixel openings P for defining the light-emitting area of ​​each sub-pixel.

[0043] The display substrate further includes: a plurality of first electrodes 103 located on the side of the pixel defining layer 102 near the substrate 101, a second electrode 104 located on the side of the first electrodes 103 away from the substrate 101, and an organic functional layer 105 located between the first electrodes 103 and the second electrodes 104. The orthographic projection of the first electrode 103 on the substrate 101 at least partially overlaps with the orthographic projection of the pixel opening P on the substrate 101.

[0044] The organic functional layer 105 is specifically an organic light-emitting layer, which can emit light under the electric field formed by the first electrode 103 and the second electrode 104. The pixel defining layer 102 is mainly used to define the light-emitting area of ​​each sub-pixel, and has both electrical insulation and physical isolation functions to prevent color mixing and crosstalk between different color light-emitting materials, thereby ensuring the clarity of the displayed image.

[0045] Currently, the pixel limiting layer 102 generally adopts a single-layer transparent structure. Although the technology of this structure is mature, it has a strong reflective ability to external ambient light. When ambient light shines on the surface of the display substrate, some of the light enters the user's field of vision after being reflected by the pixel limiting layer 102. This not only reduces the display contrast and makes the image appear washed out, but may also cause obvious glare in strong light environments, seriously affecting the viewing experience.

[0046] To at least solve one of the aforementioned technical problems, this disclosure provides a display substrate, a method for preparing the same, and a display device. The display substrate, method for preparing the same, and display device provided in this disclosure will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0047] In a first aspect, embodiments of this disclosure provide a display substrate, Figure 2 This is a schematic diagram of the structure of a display substrate provided in an embodiment of the present disclosure, such as... Figure 2As shown, the display substrate includes: a substrate 101 and a pixel defining layer 102 located on the substrate 101; the pixel defining layer 102 has a plurality of pixel openings P; the pixel defining layer 102 includes: a first inorganic insulating layer 1021, a second inorganic insulating layer 1022 and an organic insulating layer 1023 sequentially disposed away from the substrate 101; in a direction parallel to the substrate 101 and along the pixel defining layer 102 pointing towards the pixel openings P, the edge of the second inorganic insulating layer 1022 extends beyond the edges of the first inorganic insulating layer 1021 and the organic insulating layer 1023, and a plurality of micro-holes V are formed on the surface of the second inorganic insulating layer 1022 on the side away from the substrate 101.

[0048] The substrate 101 can be made of a flexible material, such as at least one high-performance polymer material selected from polyimide (PI), polyethylene naphthalate (PEN), or polyethylene terephthalate (PET). These materials not only possess excellent mechanical flexibility and deformation recovery capabilities but also high thermal stability, enabling them to withstand certain temperature loads during subsequent processes. Simultaneously, their excellent insulation properties effectively isolate upper and lower circuit layers, and their uniform surface provides a reliable adhesion interface for various organic functional layers deposited or integrated above, thus providing lightweight, flexible, and fatigue-resistant structural support and physical protection for the entire display substrate. Alternatively, the substrate 101 can be made of a rigid material, such as inorganic materials like glass. These materials possess excellent optical transmittance, extremely high dimensional stability and surface flatness, and high hardness and strong chemical corrosion resistance, maintaining their shape even under harsh process environments, providing a solid and stable planar foundation for high-precision patterning processes. In addition, glass materials have a low coefficient of thermal expansion, which helps to improve the structural reliability of devices under temperature changes, making them suitable for display applications with extremely high requirements for flatness and stability.

[0049] The pixel defining layer 102 specifically includes a first inorganic insulating layer 1021, a second inorganic insulating layer 1022, and an organic insulating layer 1023 sequentially stacked along a direction away from the substrate 101. The first inorganic insulating layer 1021 can be made of silicon nitride (SiN) and its thickness can be 300 nm to 500 nm. The second inorganic insulating layer 1022 can be made of amorphous silicon (a-Si) and its thickness can be 100 nm to 300 nm. The organic insulating layer 1023 can be made of at least one of acrylic, resin, polyimide, or benzocyclobutene and its thickness can be 500 nm to 1000 nm.

[0050] In a direction parallel to the substrate 101 and along the pixel defining layer 102 pointing towards the pixel opening P, the second inorganic insulating layer 1022 extends outward relative to the first inorganic insulating layer 1021 and the organic insulating layer 1023, forming an edge-exceeding structural feature. Through this interlayer misalignment design, the first inorganic insulating layer 1021, the second inorganic insulating layer 1022, and the organic insulating layer 1023 together constitute an undercut structure, which can effectively block the continuous coverage of functional film layers such as organic light-emitting layers between different pixel areas during subsequent evaporation processes, thereby playing a physical isolation role, preventing leakage and optical crosstalk between adjacent sub-pixels, and improving the color purity and electrical stability of the display substrate.

[0051] Meanwhile, the surface of the second inorganic insulating layer 1022 facing away from the substrate 101 undergoes a special process to form a large number of micro-holes V. These micro-holes V can alter the optical properties of the surface of the second inorganic insulating layer 1022 at the microscale, transforming the specular reflection caused by the originally flat interface into diffuse reflection. When ambient light shines on the surface of the pixel limiting layer 102, the micro-holes V can cause the light to scatter in multiple directions, thereby effectively reducing the interference of reflected light on the display image. This not only significantly reduces the glare effect under ambient light but also helps to improve the contrast performance of the display substrate in strong light environments, making the image clearer and fuller, and further enhancing the user's visual experience.

[0052] It should be noted that the micropores V can be formed by laser treatment, hydrofluoric acid (an aqueous solution of hydrogen fluoride gas) etching, etc., and their pore size can be from 0.2um to 0.5um.

[0053] Figure 3 This is a schematic diagram of another display substrate structure provided in an embodiment of the present disclosure, as shown below. Figure 3 As shown, the display substrate further includes a third inorganic insulating layer 1024 located between the second inorganic insulating layer 1022 and the organic insulating layer 1023; in a direction parallel to the substrate 101 and along the pixel defining layer 102 pointing to the pixel opening P, the edge of the third inorganic insulating layer 1024 is flush with the edge of the second inorganic insulating layer 1022.

[0054] In the stacked structure of the pixel defining layer 102, a third inorganic insulating layer 1024 is further provided. This third inorganic insulating layer 1024 is located between the second inorganic insulating layer 1022 and the organic insulating layer 1023, specifically covering the surface of the second inorganic insulating layer 1022 facing away from the substrate 101. In a direction parallel to the substrate 101 and along the pixel defining layer 102 pointing towards the pixel opening P, the edge of the third inorganic insulating layer 1024 is substantially flush with the edge of the second inorganic insulating layer 1022, and the two together constitute the edge contour of the stacked structure.

[0055] Because the surface of the second inorganic insulating layer 1022 has a large number of micro-holes V, these micro-holes V are key structures for achieving diffuse reflection and reducing ambient light reflection, but they may face the risk of damage or contamination in subsequent processes. By covering the surface of the second inorganic insulating layer 1022 with a third inorganic insulating layer 1024, the micro-holes V can be effectively protected, avoiding physical wear or chemical corrosion in subsequent processes, thereby maintaining the integrity and optical stability of the micro-holes V. In addition, the third inorganic insulating layer 1024 itself, as an inorganic material layer, has good density and adhesion, which helps to improve the structural strength and interface bonding performance of the entire pixel limiting layer 102, further ensuring the reliability and service life of the display substrate.

[0056] Figure 4 This is a schematic diagram of the structure of another display substrate provided in an embodiment of the present disclosure, as shown below. Figure 4 As shown, the organic insulating layer 1023 is made of a light-absorbing material.

[0057] Typically, the organic insulating layer 1023 can be made of at least one organic polymer material such as acrylic, resin, polyimide, or benzocyclobutene. These materials possess good film-forming properties, planarization capabilities, and process compatibility, effectively covering the uneven surface of the underlying inorganic structure and providing a flat substrate for subsequent film deposition. In conventional applications, the film formed by these materials is a transparent structure to ensure the light extraction efficiency of the pixel aperture P region.

[0058] To further improve the optical performance of the display substrate, light-shielding components, such as carbon black and other light-absorbing microparticles, can be introduced into the material system of the organic insulating layer 1023. By controlling the doping concentration and dispersion process, the originally transparent organic insulating layer 1023 can be made to exhibit a stable black state. This allows for efficient absorption of ambient light transmitted through the upper structure, significantly reducing interference from interface reflection and light scattering, thereby effectively suppressing the impact of ambient light on the display image. The black organic insulating layer 1023 not only enhances the light-shielding ability of the pixel limiting layer 102 itself, but also forms a synergistic effect with the micropores V of the lower second inorganic insulating layer 1022, jointly optimizing the anti-reflective performance of the display substrate and improving contrast performance and visual experience.

[0059] In some embodiments, such as Figures 2 to 4 As shown, the display substrate also includes a plurality of first electrodes 103 located on the side of the first inorganic insulating layer 1021 near the substrate 101; the orthographic projection of the first electrodes 103 on the substrate 101 at least partially overlaps with the orthographic projection of the pixel opening P on the substrate 101.

[0060] The first electrode 103 can specifically be an anode, and its material must be a conductive material with a high work function to ensure effective hole injection and good energy level matching with other subsequently deposited organic functional layers. For example, the material of the first electrode 103 can be selected from at least one of metal oxides such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), and tin oxide (SnO2). These materials have both high light transmittance and excellent conductivity, making them suitable for device structures that require light to be emitted from the side of the first electrode 103. The material of the first electrode 103 can also be selected from at least one of metals such as silver (Ag), aluminum (Al), platinum (Pt), gold (Au), copper (Cu), nickel (Ni), molybdenum (Mo), and titanium (Ti). These materials have high electrical conductivity and good film-forming properties, and are often used in applications requiring high conductivity. In the actual design and fabrication process, the work function, conductivity, light transmittance, film quality, and compatibility with adjacent organic functional layers of the material must be comprehensively considered based on the device structure, optical light emission method, and process conditions to ensure the overall optoelectronic performance and reliability of the display substrate. The orthographic projection of the first electrode 103 on the substrate 101 at least partially overlaps with the orthographic projection of the corresponding pixel opening P on the substrate 101. This ensures that the first electrode 103 can effectively cover the light-emitting area defined by the pixel opening P, providing a uniform and stable electric field drive for the stimulated light of the subsequent organic functional layer.

[0061] In some embodiments, such as Figures 2 to 4 As shown, the first inorganic insulating layer 1021 is filled between adjacent first electrodes 103.

[0062] The first inorganic insulating layer 1021 not only serves as the bottom layer of the pixel defining layer 102, but also plays a crucial role in planarization and isolation. Specifically, the first inorganic insulating layer 1021 fills the gap between adjacent first electrodes 103, fully covering the sidewalls and exposed surfaces of the first electrodes 103. This effectively eliminates the step difference between adjacent first electrodes 103, forming a smooth and consistent bearing surface, providing a good substrate for the subsequent deposition of films such as the second inorganic insulating layer 1022 and the organic insulating layer 1023. Simultaneously, the first inorganic insulating layer 1021 itself possesses excellent dielectric properties, forming effective electrical isolation between adjacent first electrodes 103. This prevents leakage current or parasitic capacitance effects caused by the close spacing of the first electrodes 103, ensuring the independence and stability of the driving signal for each sub-pixel. This not only improves the electrical reliability of the display substrate but also lays the foundation for achieving high-density pixel arrangement and refined light emission control.

[0063] In some embodiments, such as Figures 2 to 4As shown, the display substrate further includes: a second electrode 104 located on the side of the first electrode 103 facing away from the substrate 101, and an organic functional layer 105 located between the first electrode 103 and the second electrode 104; the second electrode 104 is a full-surface electrode; the organic functional layer 105 is formed in the pixel opening P and is separated at the edge of the second inorganic insulating layer 1022.

[0064] The second electrode 104 can specifically be a cathode, which works together with the anode (first electrode 103) to form a driving electric field on both sides of the organic functional layer 105, serving as a carrier injection layer. The second electrode 104 can be made of materials with appropriate work function and good conductivity to meet the design requirements of different device structures. In practical applications, low work function metal materials, transparent conductive oxide materials, or their composite structures can be selected according to the optical requirements and process conditions of the display substrate. By rationally optimizing the material composition and film thickness, good electron injection capability can be ensured while also considering light transmittance, conductivity, and interface stability. The second electrode 104 can be arranged across the entire surface, continuously covering the entire display area, without the need for patterning etching for each sub-pixel. This full-surface electrode design not only simplifies the fabrication process and reduces the difficulty of mask alignment and patterning, but also provides a uniform and stable common voltage reference for all sub-pixels, ensuring the uniformity and consistency of the luminous intensity of the entire display area.

[0065] The organic functional layer 105 is specifically an organic light-emitting layer, which emits light under the electric field formed by the first electrode 103 and the second electrode 104. It can be prepared using phosphorescent or fluorescent materials and precisely formed at least within the pixel opening P through a vapor deposition process. In terms of material selection, phosphorescent materials can theoretically achieve 100% internal quantum efficiency using singlet and triplet excitons, exhibiting high luminous efficacy, especially suitable for improving the efficiency of red and green phosphorescent devices; while fluorescent materials, although primarily utilizing singlet excitons for light emission, still possess advantages such as good material stability and long lifetime in blue light emission systems and some other colors. Both materials can be selectively deposited into the corresponding color pixel opening P region via vacuum thermal vapor deposition with the assistance of a fine metal mask. Because the edge of the second inorganic insulating layer 1022 in the pixel limiting layer 102 protrudes outward relative to other film layers, forming an undercut structure, this structure generates a physical shielding effect during organic material deposition, naturally isolating the organic functional layer 105 at the edge of the second inorganic insulating layer 1022. This isolation design ensures that the organic functional layer 105 is confined to the interior of each pixel opening P and cannot form a continuous film layer across adjacent pixel regions, thereby effectively preventing leakage current and optical crosstalk between different sub-pixels.

[0066] It is understandable that the organic functional layer 105 is not limited to a single organic light-emitting layer structure. In actual device design, in order to optimize carrier injection, transport, and balance, improve luminous efficiency, and reduce driving voltage, the organic functional layer 105 typically adopts a multilayer functional film stacked structure. Specifically, it may include functional layers such as a hole injection layer and a hole transport layer located on the side of the organic light-emitting layer near the first electrode 103, and functional layers such as an electron injection layer and an electron transport layer located on the side of the organic light-emitting layer near the second electrode 104. The implementation principle is the same as that in related technologies, and will not be elaborated here.

[0067] In some embodiments, Figure 5 This is a schematic diagram of a planar structure of a display substrate provided in an embodiment of the present disclosure, as shown below. Figure 5 and Figures 2 to 4 As shown, the display substrate further includes: a power connection ring 106 surrounding at least a portion of the second electrode 104; the power connection ring 106 overlaps with the second electrode 104; at the overlap of the power connection ring 106 and the second electrode 104, the edge of the organic insulating layer 1023 extends beyond the edges of the first inorganic insulating layer 1021 and the second inorganic insulating layer 1022.

[0068] The power connection ring 106 is usually surrounding the periphery of the display substrate, that is, around the edge of the second electrode 104. The two can be electrically connected in a specific area, thereby effectively transmitting the power signal (cathode signal) provided by the external driving circuit to the second electrode 104 which is arranged across the entire surface, ensuring reliable driving of each sub-pixel in the entire display area.

[0069] At the junction of the power supply overlap ring 106 and the second electrode 104, the edge of the organic insulating layer 1023 extends outward relative to the edges of the first inorganic insulating layer 1021 and the second inorganic insulating layer 1022, meaning the organic insulating layer 1023 has a wider coverage area at the junction. This effectively alleviates the steepness of the step in the overlap area, allowing the second electrode 104 to be deposited continuously along a gentler slope when covering the overlap, thus avoiding film breakage caused by excessively high steps or steep edges. This, in turn, improves the uniformity of power signal distribution and enhances the electrical stability and mechanical reliability of the display substrate during long-term operation.

[0070] In some embodiments, such as Figure 5 As shown, the display substrate also includes: a plurality of power signal terminals 107 located on the substrate 101; the plurality of power signal terminals 107 are connected to the power connection ring 106.

[0071] The power signal terminal 107 can be connected to the power connection ring 106, serving as a channel between the power connection ring 106 and the external driving circuit. This allows the power signal (cathode signal) provided by the external driving circuit to be effectively transmitted through the power connection ring 106 to the second electrode 104, ensuring reliable driving of each sub-pixel in the entire display area. It is understood that an insulating layer is also provided between the power connection ring 106 and the power signal terminal 107. The two can be connected through vias penetrating the insulating layer to transmit the power signal (cathode signal). For example, the power connection ring 106 can be disposed in the same layer as the second electrode 104, and the power signal terminal 107 can be made of a first source / drain conductive layer. Planarization and passivation layers are provided between the two, and they can be connected through vias penetrating these layers.

[0072] In some embodiments, such as Figure 5 As shown, the display substrate further includes: multiple data signal lines 108 located on the side of the first electrode 103 near the substrate 101; each data signal line 108 is connected to the first electrode 103 in the same column of sub-pixels of the same color; the display substrate further includes: multiple transition lines 109 and multiple data signal terminals 110 located between the data signal lines 108 and the first electrode 103; each data signal terminal 110 is connected to the multiple data signal lines 108 connected to the first electrode 103 in the multiple columns of sub-pixels of the same color through a transition line 109.

[0073] exist Figure 5 In the array substrate shown, the sub-pixels can specifically include red sub-pixels R, green sub-pixels G, and blue sub-pixels B. The blue sub-pixel B is located on the left side, and the red sub-pixels R and green sub-pixels G are arranged side by side on the right side of the blue sub-pixels B. This allows for pixel sharing, thereby improving the display effect of the display substrate.

[0074] Each data signal line 108 is connected to the first electrode 103 of the sub-pixels of the same color in the same column. For example, the same data signal line 108 is connected to the first electrode 103 of the red sub-pixel R in the same column, the same data signal line 108 is connected to the first electrode 103 of the green sub-pixel G in the same column, and the same data signal line 108 is connected to the first electrode 103 of the blue sub-pixel B in the same column, so that different data signals 108 can provide data signals for the sub-pixels of the same color in the same column.

[0075] In practical applications, the first electrode 103 of sub-pixels of the same color in different columns can be connected to the same data signal terminal 110 through a transition trace 109. This allows the same data signal terminal 110 to provide data signals to the first electrode 103 of sub-pixels of the same color in different columns, reducing the number of data signal terminals 110, simplifying the structure of the driver chip, and saving manufacturing costs. It should be noted that a data selector (not shown in the figure) or similar structure is also provided between the data terminal 110 and the transition trace 109 to avoid crosstalk between data signals transmitted by sub-pixels in different columns. It is understood that an insulating layer is provided between the data signal line 108 and the transition trace 109, and the two can be connected and transmit data signals through vias penetrating the insulating layer. For example, the data signal line 108 can be made of a first source-drain conductive layer, and the transition trace 109 can be made of a second source-drain conductive layer. Planarization layers and passivation layers are provided between them, and the two can be connected through vias penetrating these layers.

[0076] Secondly, embodiments of this disclosure provide a display device, which includes a display substrate as provided in any of the above embodiments. Figure 6 This is a schematic diagram of the structure of a display device provided in an embodiment of the present disclosure, such as... Figure 6 As shown, the display device further includes: an encapsulation layer 111 located on the side of the second electrode 104 facing away from the substrate 101, a black matrix layer 112 located on the side of the encapsulation layer 111 facing away from the substrate 101, and a color filter layer 113; the black matrix layer 112 has a plurality of light-transmitting openings P'; the orthographic projection of the light-transmitting openings P' on the substrate 101 at least partially overlaps with the orthographic projection of the pixel openings P on the substrate 101; the color filter layer 113 includes a plurality of color filters 1131; the color filters 1131 are disposed within the light-transmitting openings P'.

[0077] The encapsulation layer 111 may include multiple sub-encapsulation layers to improve its encapsulation effect. For example, the encapsulation layer 111 may be a composite encapsulation layer, including a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer. Specifically, the first and second inorganic encapsulation layers may be formed using inorganic materials such as silicon nitride, silicon oxide, and silicon oxynitride, while the organic encapsulation layer may be formed using organic materials such as polyimide (PI) and epoxy resin. This composite encapsulation layer can provide multiple layers of protection for structures such as the second electrode 104 in the light-emitting device on the display substrate, resulting in a better encapsulation effect and preventing damage to the light-emitting device caused by the intrusion of gases such as water and oxygen.

[0078] The black matrix layer 112 can be disposed on the encapsulation layer 111. It can absorb ambient light and prevent ambient light from shining on structures such as the first electrode 103 and causing reflection, thereby reducing the light reflectivity of the display device and improving the display effect. In this way, it is not necessary to use a polarizer to reduce the reflectivity of the display device, thereby reducing the thickness of the display device and saving manufacturing costs.

[0079] The black matrix layer 112 has multiple light-transmitting openings P', which can correspond to the pixel openings P of the pixel limiting layer 102. These openings allow light emitted from the organic functional layer 105 within the pixel openings P to pass through, thus enabling display. Simultaneously, the black matrix layer 112 prevents crosstalk between light emitted from the organic functional layers 105 in adjacent pixel openings P, thereby improving display performance. In practical applications, the area of ​​the light-transmitting openings P' can be slightly larger than the area of ​​the pixel openings P, allowing for complete projection of light emitted from the organic functional layers 105 within the pixel openings P.

[0080] The light-transmitting opening P' in the black matrix layer 112 can also project a portion of the ambient light onto the first electrode 103. The first electrode 103 can reflect this portion of the ambient light, and the reflected light can pass through the color filter 1131 in the color filter layer 113. The ambient light can be filtered into light of the corresponding color. For example, the color of the color filter 1131 is the same as the color of the organic functional layer 105 in the corresponding pixel opening P. In this way, the ambient light can be filtered into the light required for display, thereby improving the light utilization rate and increasing the display brightness of the display device.

[0081] It should be noted that this display device can be any product or component with display functionality, such as a monitor, tablet computer, laptop computer, digital photo frame, or navigator. Its implementation principle is similar to that of the display substrate described above, and will not be repeated here.

[0082] Thirdly, embodiments of this disclosure provide a method for preparing a display substrate. Figure 7 This is a schematic flowchart of a method for fabricating a display substrate according to an embodiment of the present disclosure, as shown below. Figure 7 As shown, the method for preparing the display substrate includes the following steps S701 to S704.

[0083] S701, a first inorganic insulating layer and a second inorganic insulating layer are sequentially formed on the substrate.

[0084] In step S701 above, the first inorganic insulating layer 1021 can be made of silicon nitride (SiN) and its thickness can be 300 nm to 500 nm. The second inorganic insulating layer 1022 can be made of amorphous silicon (a-Si) and its thickness can be 100 nm to 300 nm.

[0085] S702 uses a patterning process to pattern the first and second inorganic insulating layers to form pixel openings.

[0086] In step S702 above, a mask can be used to pattern the first inorganic insulating layer 1021 and the second inorganic insulating layer 1022, and etch some of the structures therein to form a pixel opening P for defining the light-emitting area.

[0087] S703, roughening the surface of the second inorganic insulating layer on the side away from the substrate to form multiple micro-holes.

[0088] In step S703 above, micropores V can be formed on the surface of the second inorganic insulating layer 1022 by means of laser treatment, hydrofluoric acid (an aqueous solution of hydrogen fluoride gas) corrosion, etc., and the pore size can be 0.2 μm to 0.5 μm.

[0089] S704, an organic insulating layer is formed on the side of the second inorganic insulating layer away from the substrate.

[0090] In step S704 above, the organic insulating layer 1023 can be made of at least one of acrylic, resin, polyimide or benzocyclobutene, and its thickness can be 500 nanometers to 1000 nanometers.

[0091] In a direction parallel to the substrate 101 and along the pixel defining layer 102 pointing towards the pixel opening P, the second inorganic insulating layer 1022 extends outward relative to the first inorganic insulating layer 1021 and the organic insulating layer 1023, forming an edge-exceeding structural feature. Through this interlayer misalignment design, the first inorganic insulating layer 1021, the second inorganic insulating layer 1022, and the organic insulating layer 1023 together constitute an undercut structure, which can effectively block the continuous coverage of functional film layers such as organic light-emitting layers between different pixel areas during subsequent evaporation processes, thereby playing a physical isolation role, preventing leakage and optical crosstalk between adjacent sub-pixels, and improving the color purity and electrical stability of the display substrate.

[0092] Meanwhile, the surface of the second inorganic insulating layer 1022 facing away from the substrate 101 undergoes a special process to form a large number of micro-holes V. These micro-holes V can alter the optical properties of the surface of the second inorganic insulating layer 1022 at the microscale, transforming the specular reflection caused by the originally flat interface into diffuse reflection. When ambient light shines on the surface of the pixel limiting layer 102, the micro-holes V can cause the light to scatter in multiple directions, thereby effectively reducing the interference of reflected light on the display image. This not only significantly reduces the glare effect under ambient light but also helps to improve the contrast performance of the display substrate in strong light environments, making the image clearer and fuller, and further enhancing the user's visual experience.

[0093] In some embodiments, such as Figure 7 As shown, in step S704 above, an organic insulating layer is formed on the side of the second inorganic insulating layer away from the substrate. Before this step, step S703A is further included, in which a third inorganic insulating layer is formed on the side of the second inorganic insulating layer away from the substrate.

[0094] In step S703A above, the third inorganic insulating layer 1024 is located between the second inorganic insulating layer 1022 and the organic insulating layer 1023, specifically covering the side surface of the second inorganic insulating layer 1022 facing away from the substrate 101. In a direction parallel to the substrate 101 and along the pixel defining layer 102 pointing towards the pixel opening P, the edge of the third inorganic insulating layer 1024 is substantially flush with the edge of the second inorganic insulating layer 1022, and the two together constitute the edge contour of the stacked structure.

[0095] Because the surface of the second inorganic insulating layer 1022 has a large number of micro-holes V, these micro-holes V are key structures for achieving diffuse reflection and reducing ambient light reflection, but they may face the risk of damage or contamination in subsequent processes. By covering the surface of the second inorganic insulating layer 1022 with a third inorganic insulating layer 1024, the micro-holes V can be effectively protected, avoiding physical wear or chemical corrosion in subsequent processes, thereby maintaining the integrity and optical stability of the micro-holes V. In addition, the third inorganic insulating layer 1024 itself, as an inorganic material layer, has good density and adhesion, which helps to improve the structural strength and interface bonding performance of the entire pixel limiting layer 102, further ensuring the reliability and service life of the display substrate.

[0096] It should be noted that the dimensions of layers and regions may be exaggerated in the accompanying drawings for clarity. Furthermore, it is understood that when an element or layer is referred to as being "on" another element or layer, it can be directly on the other element, or there may be intermediate layers. Additionally, it is understood that when an element or layer is referred to as being "below" another element or layer, it can be directly below the other element, or there may be more than one intermediate layer or element. Furthermore, it is also understood that when a layer or element is referred to as being "between" two layers or two elements, it can be the only layer between the two layers or two elements, or there may be more than one intermediate layer or element. Similar reference numerals throughout indicate similar elements.

[0097] In the several embodiments provided in this disclosure, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the positions of the components shown are only logical functional positions, and in actual implementation, they may be arranged in other positions.

Claims

1. A display substrate, characterized in that, The display substrate includes: a substrate, and a pixel defining layer located on the substrate; the pixel defining layer has a plurality of pixel openings; the pixel defining layer includes: a first inorganic insulating layer, a second inorganic insulating layer, and an organic insulating layer disposed sequentially along a direction away from the substrate. In a direction parallel to the substrate and along the pixel defining layer toward the pixel opening, the edge of the second inorganic insulating layer extends beyond the edges of the first inorganic insulating layer and the organic insulating layer, and a plurality of micropores are formed on the surface of the second inorganic insulating layer facing away from the substrate.

2. The display substrate according to claim 1, characterized in that, The display substrate further includes: a third inorganic insulating layer located between the second inorganic insulating layer and the organic insulating layer; In a direction parallel to the substrate and along the pixel defining layer toward the pixel opening, the edge of the third inorganic insulating layer is flush with the edge of the second inorganic insulating layer.

3. The display substrate according to claim 2, characterized in that, The organic insulating layer is made of a light-absorbing material.

4. The display substrate according to claim 1, characterized in that, The display substrate further includes: a plurality of first electrodes located on the side of the first inorganic insulating layer near the substrate; The orthographic projection of the first electrode on the substrate at least partially overlaps with the orthographic projection of the pixel opening on the substrate.

5. The display substrate according to claim 4, characterized in that, The first inorganic insulating layer fills the space between adjacent first electrodes.

6. The display substrate according to claim 4, characterized in that, The display substrate further includes: a second electrode located on the side of the first electrode opposite to the substrate, and an organic functional layer located between the first electrode and the second electrode; The second electrode is a full-surface electrode; the organic functional layer is formed within the pixel opening and is separated at the edge of the second inorganic insulating layer.

7. The display substrate according to claim 6, characterized in that, The display substrate further includes: a power connection ring surrounding at least a portion of the second electrode; the power connection ring is connected to the second electrode; At the junction of the power supply overlap ring and the second electrode, the edge of the organic insulating layer extends beyond the edges of the first inorganic insulating layer and the second inorganic insulating layer.

8. The display substrate according to claim 7, characterized in that, The display substrate further includes: a plurality of power signal terminals located on the substrate; Multiple power signal terminals are connected to the power connection ring.

9. The display substrate according to claim 7, characterized in that, The display substrate further includes: a plurality of data signal lines located on the side of the first electrode near the substrate; each of the data signal lines is connected to the first electrode in the same column of sub-pixels of the same color; The display substrate further includes: multiple adapter lines and multiple data signal terminals located between the data signal lines and the first electrode; each data signal terminal is connected to multiple data signal lines connected to the first electrode in multiple columns of sub-pixels of the same color through one adapter line.

10. A display device, characterized in that, The display device includes a display substrate as described in any one of claims 1 to 9.

11. The display device according to claim 10, characterized in that, The display device further includes: an encapsulation layer located on the side of the second electrode facing away from the substrate, a black matrix layer and a color filter layer located on the side of the encapsulation layer facing away from the substrate; The black matrix layer has multiple light-transmitting openings; the orthographic projection of the light-transmitting openings on the substrate at least partially overlaps with the orthographic projection of the pixel openings on the substrate. The color filter layer includes multiple color filters; the color filters are disposed within the light-transmitting opening.

12. A method for preparing a display substrate, characterized in that, The method for preparing the display substrate includes: A first inorganic insulating layer and a second inorganic insulating layer are sequentially formed on the substrate. Using patterning techniques, the first inorganic insulating layer and the second inorganic insulating layer are patterned to form pixel openings; The surface of the second inorganic insulating layer on the side away from the substrate is roughened to form multiple micropores; An organic insulating layer is formed on the side of the second inorganic insulating layer away from the substrate; in a direction parallel to the substrate and along the pixel defining layer toward the pixel opening, the edge of the second inorganic insulating layer extends beyond the edges of the first inorganic insulating layer and the organic insulating layer.

13. The method for preparing a display substrate according to claim 12, characterized in that, Before forming an organic insulating layer on the side of the second inorganic insulating layer away from the substrate, the method further includes: A third inorganic insulating layer is formed on the side of the second inorganic insulating layer away from the substrate; the edge of the third inorganic insulating layer is flush with the edge of the second inorganic insulating layer in a direction parallel to the substrate and along the pixel defining layer toward the pixel opening.

Images