Display substrate, display panel and preparation method of display substrate

Abstract

The invention provides a display substrate. The display substrate comprises a substrate body; a plurality of conductive patterns located on the substrate; the light-emitting elements are located on the substrate, the light-emitting elements are arranged in an array and distributed on the substrate at intervals, at least one light-emitting element comprises a first electrode, a first type semiconductor layer, a light-emitting layer, a second type semiconductor layer and a second electrode, the first electrode is electrically connected with the conductive pattern, and the second electrode is electrically connected with the second type semiconductor layer. The first type semiconductor layer is located on the side, away from the substrate, of the first electrode, the light-emitting layer is located on the side, away from the substrate, of the first type semiconductor layer, the second type semiconductor layer is located on the side, away from the substrate, of the light-emitting layer, and the second electrode is located on the side, away from the substrate, of the second type semiconductor layer; and the conductive shading part is positioned on the substrate, the shading part is positioned in a gap between two adjacent light-emitting elements, and the shading part is electrically connected with the second electrode.

Description

Technical Field

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

[0002] Light Emitting Diode (LED) technology has been developed for nearly three decades, and its application scope has been continuously expanded. For example, it can be applied to the display field, used as a backlight source for display devices or as an LED display screen. With the development of technology, the resolution of LED display products has gradually increased. With the increase in resolution, the pixel pitch in LED display products has gradually decreased. In LED display products with small pixel pitch, how to design the structure of the display panel to reduce or even avoid crosstalk between pixels is one of the topics that display product developers are concerned about.

[0003] The above information disclosed in this section is only for understanding the background of the inventive concept of the present disclosure and therefore the above information may contain information that does not constitute the prior art. Summary of the invention

[0004] In one aspect, a display substrate is provided, comprising: a base substrate; a plurality of conductive patterns on the base substrate; a plurality of light-emitting elements on the base substrate, the plurality of light-emitting elements being arranged in an array and spaced apart from each other on the base substrate, at least one light-emitting element comprising a first electrode, a first-type semiconductor layer, a light-emitting layer, a second-type semiconductor layer, and a second electrode, the first electrode being electrically connected to the conductive pattern, the first-type semiconductor layer being located on a side of the first electrode away from the base substrate, the light-emitting layer being located on a side of the first-type semiconductor layer away from the base substrate, the second-type semiconductor layer being located on a side of the light-emitting layer away from the base substrate, the second electrode being located on a side of the second-type semiconductor layer away from the base substrate; and a conductive shading portion on the base substrate, the shading portion being located in a gap between two adjacent light-emitting elements, the shading portion being electrically connected to the second electrode.

[0005] According to some exemplary embodiments, the light-emitting layer includes a top surface away from the substrate, the light-shielding portion includes a top surface away from the substrate, and the substrate includes a first surface facing the light-emitting element; the height of the top surface of the light-shielding portion relative to the first surface is greater than the height of the top surface of the light-emitting layer relative to the first surface.

[0006] According to some exemplary embodiments, the second-type semiconductor layer includes a top surface away from the substrate, and a height of a top surface of the light shielding portion relative to the first surface is greater than a height of a top surface of the second-type semiconductor layer relative to the first surface.

[0007] According to some exemplary embodiments, the first-type semiconductor layer includes a bottom surface close to the substrate, the shading portion includes a bottom surface close to the substrate, and the height of the bottom surface of the shading portion relative to the first surface is less than the height of the bottom surface of the first-type semiconductor layer relative to the first surface.

[0008] According to some exemplary embodiments, a bottom surface of the light shielding portion contacts the first surface.

[0009] According to some exemplary embodiments, the first-type semiconductor layer includes a bottom surface close to the substrate, the light-emitting element includes a side wall connecting the top surface of the second-type semiconductor layer and the bottom surface of the first-type semiconductor layer, and the side wall of the light-emitting element is inclined relative to the bottom surface of the first-type semiconductor layer.

[0010] According to some exemplary embodiments, the light shielding portion includes a bottom surface close to the base substrate and a side wall connecting the top surface and the bottom surface of the light shielding portion, and the side wall of the light shielding portion is inclined relative to the bottom surface of the light shielding portion.

[0011] According to some exemplary embodiments, the side wall of the light emitting element is inclined at a first angle relative to the bottom surface of the first-type semiconductor layer, and the first angle is less than or equal to 65°; and / or the side wall of the light shading portion is inclined at a second angle relative to the bottom surface of the light shading portion, and the second angle is less than or equal to 65°.

[0012] According to some exemplary embodiments, the display panel also includes: a first insulating layer located between the second-type semiconductor layer and the layer where the second electrode is located; and a plurality of openings located in the first insulating layer; and the first insulating layer includes a first portion and a second portion, the first portion of the first insulating layer covers a portion of the top surface of the second-type semiconductor layer, the opening exposes another portion of the top surface of the second-type semiconductor layer, and the second portion of the first insulating layer covers the side walls of the light-emitting element.

[0013] According to some exemplary embodiments, the second electrode includes a first electrode portion, a second electrode portion and a third electrode portion, the first electrode portion covers a first portion of the first insulating layer, the second electrode portion covers a second portion of the first insulating layer, and the third electrode portion is located in the opening; and the shading portion is in contact with at least the first electrode portion of the second electrode.

[0014] According to some exemplary embodiments, an orthographic projection of the light shielding portion on the base substrate is spaced apart from an orthographic projection of the second portion of the first insulating layer on the base substrate.

[0015] According to some exemplary embodiments, the light shielding portion includes a first sub-light shielding portion and a second sub-light shielding portion, the first sub-light shielding portion contacts the first electrode portion of the second electrode, and the second sub-light shielding portion contacts the second electrode portion of the second electrode.

[0016] According to some exemplary embodiments, the orthographic projection of the second sub-light-shielding portion on the base substrate at least partially overlaps with the orthographic projection of the second electrode portion of the second electrode on the base substrate; and / or, the orthographic projection of the second sub-light-shielding portion on the base substrate at least partially overlaps with the orthographic projection of the second portion of the first insulating layer on the base substrate.

[0017] According to some exemplary embodiments, the second electrode includes a top surface away from the base substrate, and a height of a top surface of the light shielding portion relative to the first surface is greater than a height of a top surface of the second electrode relative to the first surface.

[0018] According to some exemplary embodiments, at least one light-emitting element includes a first sub-light-emitting element and a second sub-light-emitting element, the first sub-light-emitting element and the second sub-light-emitting element are stacked in a direction perpendicular to a first surface of a substrate, the first surface being a surface of the substrate facing the light-emitting element; the first sub-light-emitting element includes a first electrode, a first-type semiconductor layer, a light-emitting layer, and a second-type semiconductor layer, the first electrode is electrically connected to the conductive pattern, the first-type semiconductor layer of the first sub-light-emitting element is located on a side of the first electrode away from the substrate, the light-emitting layer of the first sub-light-emitting element is located on a side of the first-type semiconductor layer of the first sub-light-emitting element away from the substrate, and the second-type semiconductor layer of the first sub-light-emitting element is located on a side of the first-type semiconductor layer of the first sub-light-emitting element away from the substrate The second sub-light-emitting element comprises a first-type semiconductor layer, a light-emitting layer, a second-type semiconductor layer and a second electrode, the first-type semiconductor layer of the second sub-light-emitting element is located on a side of the second-type semiconductor layer of the first sub-light-emitting element away from the substrate substrate, the light-emitting layer of the second sub-light-emitting element is located on a side of the first-type semiconductor layer of the second sub-light-emitting element away from the substrate substrate, the second-type semiconductor layer of the second sub-light-emitting element is located on a side of the light-emitting layer of the second sub-light-emitting element away from the substrate substrate, and the second electrode is located on a side of the second-type semiconductor layer of the second sub-light-emitting element away from the substrate substrate; and the second-type semiconductor layer of the first sub-light-emitting element and the first-type semiconductor layer of the second sub-light-emitting element are electrically connected via the first bonding layer.

[0019] According to some exemplary embodiments, the light-emitting layer of the second sub-light-emitting element includes a top surface away from the substrate, the light-shielding portion includes a top surface away from the substrate, and the height of the top surface of the light-shielding portion relative to the first surface is greater than the height of the top surface of the light-emitting layer of the second sub-light-emitting element relative to the first surface; and / or, the light-emitting layer of the first sub-light-emitting element includes a bottom surface close to the substrate, the light-shielding portion includes a bottom surface close to the substrate, and the height of the bottom surface of the light-shielding portion relative to the first surface is less than the height of the bottom surface of the light-emitting layer of the first sub-light-emitting element relative to the first surface.

[0020] According to some exemplary embodiments, the second-type semiconductor layer of the second sub-light-emitting element includes a top surface away from the substrate, and the height of the top surface of the light-shielding portion relative to the first surface is greater than the height of the top surface of the second-type semiconductor layer of the second sub-light-emitting element relative to the first surface; and / or, the first-type semiconductor layer of the first sub-light-emitting element includes a bottom surface close to the substrate, and the height of the bottom surface of the light-shielding portion relative to the first surface is less than the height of the bottom surface of the first-type semiconductor layer of the first sub-light-emitting element relative to the first surface.

[0021] According to some exemplary embodiments, a bottom surface of the light shielding portion contacts the first surface.

[0022] According to some exemplary embodiments, the light-emitting element includes a side wall connecting the top surface of the second-type semiconductor layer of the second sub-light-emitting element and the bottom surface of the first-type semiconductor layer of the first sub-light-emitting element, and the side wall of the light-emitting element is inclined relative to the bottom surface of the first-type semiconductor layer of the first sub-light-emitting element.

[0023] According to some exemplary embodiments, the light shielding portion includes a bottom surface close to the base substrate and a side wall connecting the top surface and the bottom surface of the light shielding portion, and the side wall of the light shielding portion is inclined relative to the bottom surface of the light shielding portion.

[0024] According to some exemplary embodiments, the side wall of the light emitting element is inclined at a first angle relative to the bottom surface of the first-type semiconductor layer, and the first angle is less than or equal to 65°; and / or the side wall of the light shading portion is inclined at a second angle relative to the bottom surface of the light shading portion, and the second angle is less than or equal to 65°.

[0025] According to some exemplary embodiments, the first bonding layer includes a bottom surface of the second-type semiconductor layer facing the first sub-light-emitting element, a top surface of the first-type semiconductor layer facing the second sub-light-emitting element, and a side wall connecting the bottom surface and the top surface of the first bonding layer; the side wall of the first bonding layer is indented inwardly relative to the side wall of the second-type semiconductor layer of the adjacent first sub-light-emitting element, and / or the side wall of the first bonding layer is indented inwardly relative to the side wall of the first-type semiconductor layer of the adjacent second sub-light-emitting element.

[0026] According to some exemplary embodiments, the display substrate further includes a lens located on the base substrate, the lens is located on a side of the second electrode away from the base substrate, and an orthographic projection of the lens on the base substrate covers an orthographic projection of the opening on the base substrate.

[0027] According to some exemplary embodiments, the orthographic projection of the lens on the substrate and the orthographic projection of the second portion of the first insulating layer on the substrate at least partially overlap; and / or, the orthographic projection of the lens on the substrate and the orthographic projection of the second portion of the second electrode on the substrate at least partially overlap.

[0028] According to some exemplary embodiments, an orthographic projection of the lens on the base substrate at least partially overlaps with an orthographic projection of the light shielding portion on the base substrate.

[0029] In another aspect, a display panel is provided, comprising: the display substrate as described above; a cover plate disposed opposite to the display substrate; and an adhesive layer located between the display substrate and the cover plate.

[0030] On the other hand, a method for preparing a display substrate is provided, the method comprising: forming a plurality of conductive patterns on a base substrate; bonding a light-emitting element epitaxial wafer to the base substrate on which the plurality of conductive patterns are formed; patterning the light-emitting element epitaxial wafer to form a plurality of light-emitting elements distributed in an array and spaced apart from each other on the base substrate, wherein at least one light-emitting element comprises a first electrode, a first-type semiconductor layer, a light-emitting layer and a second-type semiconductor layer, the first electrode is electrically connected to the conductive pattern, the first-type semiconductor layer is located on a side of the first electrode away from the base substrate, the light-emitting layer is located on a side of the first-type semiconductor layer away from the base substrate, and the second-type semiconductor layer is located on a side of the light-emitting layer away from the base substrate; forming a second electrode on a side of the second-type semiconductor layer away from the base substrate; and forming a conductive shading portion in the gaps between the plurality of light-emitting elements, the shading portion being electrically connected to the second electrode.

[0031] On the other hand, a method for preparing a display substrate is provided, the preparation method comprising: forming a second sub-light-emitting element epitaxial structure on a second substrate; forming a second sub-bonding layer on a side of the second sub-light-emitting element epitaxial structure away from the second substrate; patterning the second sub-light-emitting element epitaxial structure and the second bonding layer to form a second sub-light-emitting element, wherein the second sub-light-emitting element comprises a second-type semiconductor layer, a light-emitting layer and a first-type semiconductor layer, the second-type semiconductor layer of the second sub-light-emitting element is located on the second substrate, the light-emitting layer of the second sub-light-emitting element is located on a side of the second-type semiconductor layer of the second sub-light-emitting element away from the first substrate, and the first-type semiconductor layer of the second sub-light-emitting element is located on a side of the light-emitting layer of the second sub-light-emitting element away from the first substrate; forming a first sub-light-emitting element epitaxial structure on the first substrate; forming a first sub-bonding layer on a side of the first sub-light-emitting element epitaxial structure away from the first substrate; bonding the second sub-light-emitting element and the first sub-light-emitting element epitaxial structure through the first sub-bonding layer and the second sub-bonding layer; removing the first substrate; patterning the first sub-light-emitting element epitaxial structure and the first sub-bonding layer; The method comprises the steps of: patterning the rows to form a first sub-light-emitting element, wherein the first sub-light-emitting element comprises a second-type semiconductor layer, a light-emitting layer and a first-type semiconductor layer, the second-type semiconductor layer of the first sub-light-emitting element is located on the first sub-bonding layer, the light-emitting layer of the first sub-light-emitting element is located on a side of the second-type semiconductor layer of the first sub-light-emitting element away from the second substrate, and the first-type semiconductor layer of the first sub-light-emitting element is located on a side of the light-emitting layer of the first sub-light-emitting element away from the second substrate; and bonding the second substrate formed with the first sub-light-emitting element and the second sub-light-emitting element to the substrate substrate, and removing the second substrate to form a plurality of light-emitting elements on the substrate substrate, wherein at least one light-emitting element comprises a first sub-light-emitting element and a second sub-light-emitting element, the first sub-light-emitting element and the second sub-light-emitting element are stacked in a direction perpendicular to a first surface of the substrate substrate, and the first surface is a surface of the substrate substrate facing the light-emitting element; forming a second electrode on a side of the second-type semiconductor layer of the second sub-light-emitting element away from the substrate substrate; and forming a conductive shading portion in the gap between the plurality of light-emitting elements, the shading portion being electrically connected to the second electrode.

[0032] On the other hand, a method for preparing a display substrate is provided, the method comprising: forming a second sub-light-emitting element epitaxial structure on a second substrate; forming a second sub-bonding layer on a side of the second sub-light-emitting element epitaxial structure away from the second substrate; forming a first sub-light-emitting element epitaxial structure on a first substrate; forming a first sub-bonding layer on a side of the first sub-light-emitting element epitaxial structure away from the first substrate; bonding the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure through the first sub-bonding layer and the second sub-bonding layer; removing the first substrate; and bonding the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure to the first substrate. The substrate is bonded to the substrate substrate, the second substrate is removed, and the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure are patterned to form a plurality of light-emitting elements on the substrate substrate, wherein at least one light-emitting element includes a first sub-light-emitting element and a second sub-light-emitting element, the first sub-light-emitting element and the second sub-light-emitting element are stacked in a direction perpendicular to a first surface of the substrate substrate, and the first surface is a surface of the substrate substrate facing the light-emitting element; a second electrode is formed on a side of the second sub-light-emitting element away from the substrate substrate; and a conductive shading portion is formed in the gaps between the plurality of light-emitting elements, the shading portion being electrically connected to the second electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Other objects and advantages of the present disclosure will be apparent from the following description of the present disclosure with reference to the accompanying drawings and will help to have a comprehensive understanding of the present disclosure.

[0034] Figure 1 A schematic plan view of a display panel according to an embodiment of the present disclosure is schematically shown.

[0035] Figure 2 A cross-sectional schematic diagram of a display panel according to an embodiment of the present disclosure is schematically shown.

[0036] Figure 3 The figure schematically shows the tilt angle of the light emitting element according to the embodiment of the present disclosure.

[0037] Figure 4 The diagram schematically shows the spacing between the light shielding portion and the first insulating layer projected on the base substrate according to an embodiment of the present disclosure.

[0038] Figure 5 A cross-sectional schematic diagram of a display panel according to an embodiment of the present disclosure is schematically shown.

[0039] Figure 6 A cross-sectional view of a display substrate according to an embodiment of the present disclosure is schematically shown.

[0040] Figure 7 The figure schematically shows a shape diagram of a first bonding layer according to an embodiment of the present disclosure.

[0041] Figure 8 The light spot effect diagram of the flip chip is schematically shown.

[0042] Fig. 9 The light spot effect diagram of the display substrate according to the embodiment of the present disclosure is schematically shown.

[0043] Fig.10 is a flow chart of a method for preparing a display substrate according to an embodiment of the present disclosure.

[0044] Fig.11 It is a schematic diagram of the structure of the epitaxial wafer of the light-emitting element according to the embodiment of the present disclosure.

[0045] Fig.12 It is a schematic diagram of the patterning structure of the light-emitting element epitaxial wafer according to the embodiment of the present disclosure.

[0046] Fig.13 is a schematic diagram of a first insulating layer according to an embodiment of the present disclosure.

[0047] Fig.14 is a schematic diagram of a second electrode according to an embodiment of the present disclosure.

[0048] Fig.15 Schematic diagram of a shading portion according to an embodiment of the present disclosure.

[0049] Fig.16 is a flow chart of a method for preparing a display substrate according to an embodiment of the present disclosure.

[0050] Fig.17 It is a schematic diagram of the structure of the epitaxial wafer of the light-emitting element according to the embodiment of the present disclosure.

[0051] Fig.18 Schematic diagram of the second sub-bonding layer structure according to an embodiment of the present disclosure.

[0052] Fig.19 It is a schematic diagram of the patterning structure of the light-emitting element epitaxial wafer according to the embodiment of the present disclosure.

[0053] Fig. 20 is a schematic diagram of the first temporary bonding layer structure according to an embodiment of the present disclosure.

[0054] Fig.21 It is a schematic diagram of bonding the first sub-light-emitting element epitaxial structure and the first substrate according to an embodiment of the present disclosure.

[0055] Fig. 22 FIG. 4 is a schematic diagram of removing the first temporary substrate according to an embodiment of the present disclosure.

[0056] Fig.23 It is a schematic diagram of forming a first sub-bonding layer according to an embodiment of the present disclosure.

[0057] Fig.24It is a schematic diagram of the epitaxial structure of bonding the second sub-light-emitting element and the first sub-light-emitting element according to an embodiment of the present disclosure.

[0058] Fig.25 It is a schematic diagram of removing the first substrate according to an embodiment of the present disclosure.

[0059] Fig.26 It is a schematic diagram of patterning the first sub-light-emitting element epitaxial structure and the first sub-bonding layer according to an embodiment of the present disclosure.

[0060] Fig. 27 It is a schematic diagram of bonding the second substrate to the substrate base according to an embodiment of the present disclosure.

[0061] Fig.28 is a schematic diagram of an insulating layer according to an embodiment of the present disclosure.

[0062] Fig.29 is a schematic diagram of a second electrode according to an embodiment of the present disclosure.

[0063] Fig.30 Schematic diagram of a shading portion according to an embodiment of the present disclosure.

[0064] Fig.31 is a flow chart of another method for preparing a display substrate according to an embodiment of the present disclosure.

[0065] Fig.32 It is a schematic diagram of the epitaxial structure of the second sub-light-emitting element and the epitaxial structure of the first sub-light-emitting element according to an embodiment of the present disclosure.

[0066] Fig.33 It is a schematic diagram of bonding and graphing the second substrate of the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure to the substrate base according to the embodiment of the present disclosure.

[0067] Fig.34 Schematic diagram of a cover plate and an adhesive layer according to an embodiment of the present disclosure.

[0068] It should be noted that, for the sake of clarity, in the drawings used to describe the embodiments of the present disclosure, the sizes of layers, structures or regions may be enlarged or reduced, that is, these drawings are not drawn according to the actual scale. DETAILED DESCRIPTION

[0069] In the following description, for the purpose of explanation, many specific details are set forth to provide a comprehensive understanding of various exemplary embodiments. However, it is apparent that various exemplary embodiments may be implemented without these specific details or with one or more equivalent arrangements. In other cases, well-known structures and devices are shown in block diagram form to avoid making various exemplary embodiments unnecessarily obscure. In addition, various exemplary embodiments may be different, but not necessarily exclusive. For example, the specific shape, configuration, and characteristics of an exemplary embodiment may be used or implemented in another exemplary embodiment without departing from the inventive concept.

[0070] In the accompanying drawings, the size and relative size of the elements may be exaggerated for the purpose of clarity and / or description. Thus, the size and relative size of the individual elements are not necessarily limited to the size and relative size shown in the drawings. When the exemplary embodiments may be implemented differently, the specific process sequence may be performed differently from the described sequence. For example, two processes described in succession may be performed substantially simultaneously or in an order opposite to the described sequence. In addition, the same reference numerals represent the same elements.

[0071] When an element is described as "on" another element, "connected to" another element or "coupled to" another element, the element may be directly on another element, directly connected to another element or directly coupled to another element, or there may be an intermediate element. However, when an element is described as "directly on" another element, "directly connected to" another element or "directly coupled to" another element, there is no intermediate element. Other terms and / or expressions used to describe the relationship between elements should be interpreted in a similar manner, for example, "between..." versus "directly between...", "adjacent" versus "directly adjacent" or "on..." versus "directly on...", etc. In addition, the term "connection" may refer to physical connection, electrical connection, communication connection and / or fluid connection. In addition, the X-axis, Y-axis and Z-axis are not limited to the three axes of the rectangular coordinate system, and can be interpreted in a broader sense. For example, the X-axis, Y-axis and Z-axis may be perpendicular to each other, or may represent different directions that are not perpendicular to each other. For the purpose of this disclosure, "at least one of X, Y, and Z" and "at least one selected from the group consisting of X, Y, and Z" may be interpreted as only X, only Y, only Z, or any combination of two or more of X, Y, and Z such as XYZ, XY, YZ, and XZ. As used herein, the term "and / or" includes any and all combinations of one or more of the listed associated items.

[0072] It should be understood that, although the terms first, second, etc. may be used herein to describe different elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the exemplary embodiment, a first element may be named a second element, and similarly, a second element may be named a first element.

[0073] In this article, inorganic light emitting diode refers to a light emitting element made of inorganic materials, wherein LED represents an inorganic light emitting element different from OLED. Specifically, inorganic light emitting elements may include sub-millimeter light emitting diodes (Mini Light Emitting Diode, abbreviated as Mini LED in English) and micro light emitting diodes (Micro Light Emitting Diode, abbreviated as Micro LED in English). Among them, micro light emitting diodes (i.e. Micro LED) refer to ultra-small light emitting diodes with a grain size of less than 100 microns, and sub-millimeter light emitting diodes (i.e. Mini LED) refer to small light emitting diodes with a grain size between MicroLED and traditional LED. For example, the grain size of Mini LED can be between 50 and 400 microns. PPI (Pixels Per Inch) indicates the number of pixels per inch.

[0074] With the development of technology, LED display devices have developed rapidly. For example, micro-LED display technology has begun to be applied to AR applications. The inventors have found through research that, on the one hand, micro-LED display technology for AR applications usually requires a PPI of 5000 or higher, and the distance between pixels is very small. Between pixels distributed at a small distance, the light of the light-emitting elements will interfere with each other, resulting in cross-color and crosstalk between pixels. If the LED is etched into a vertical structure, because the refractive index of GaN is relatively large, the critical angle in the air is only 25 degrees, that is, the light within 25° oscillates repeatedly in the structure and cannot become an effective light emitting device to become the display brightness.

[0075] Figure 1 A schematic plan view of a display panel according to an embodiment of the present disclosure is schematically shown.

[0076] Reference Figure 1 The display substrate 100 may include a base substrate 1, a plurality of conductive patterns 2 located on the base substrate 1, and a plurality of light-emitting elements 3 located on the base substrate 1. The plurality of light-emitting elements 3 are distributed on the base substrate 1 in an array and spaced apart from each other, and the orthographic projection of each light-emitting element 3 on the base substrate 1 at least partially overlaps with the orthographic projection of the conductive pattern 2 on the substrate.

[0077] For example, the material of the substrate 1 may include but is not limited to glass, quartz, plastic, silicon, polyimide, etc.

[0078] exist Figure 1 In the exemplary embodiment, the first direction D1 and the second direction D2 are schematically shown. For example, a plurality of light emitting elements 3 may be arranged in an array along the first direction D1 and the second direction D2. It should be noted that the embodiments of the present disclosure are not limited thereto.

[0079] Figure 2 A cross-sectional schematic diagram of a display panel according to an embodiment of the present disclosure is schematically shown.

[0080] Reference Figure 2 At least one light-emitting element 3 includes a first electrode 4, a first-type semiconductor layer 5, a light-emitting layer 6, a second-type semiconductor layer 7 and a second electrode 8, the first electrode 4 is electrically connected to the conductive pattern 2, the first-type semiconductor layer 5 is located on a side of the first electrode 4 away from the substrate 1, the light-emitting layer 6 is located on a side of the first-type semiconductor layer 5 away from the substrate 1, the second-type semiconductor layer 7 is located on a side of the light-emitting layer 6 away from the substrate 1, and the second electrode 8 is located on a side of the second-type semiconductor layer 7 away from the substrate 1; and a conductive shading portion 9 located on the substrate 1, the shading portion 9 is located in a gap between two adjacent light-emitting elements 3, and the shading portion 9 is electrically connected to the second electrode 8.

[0081] For example, the first electrode 4 may be an electrode formed of a transparent conductive material. The first semiconductor layer 5 may be an N-type semiconductor, such as N-type gallium nitride (GaN), denoted as N-GaN. The second electrode 8 may be an electrode formed of a transparent conductive material. The second semiconductor layer 7 may be a P-type semiconductor, such as P-type gallium nitride (GaN), denoted as P-GaN.

[0082] The material of the light shielding portion 9 is a metal material with good electrical conductivity, including but not limited to copper, aluminum, tin or other alloy materials.

[0083] In the embodiment of the present disclosure, the light emitting layer 6 includes a top surface 6A away from the base substrate 1, the light shielding portion 9 includes a top surface 9A away from the base substrate 1, and the base substrate 1 includes a first surface 1A facing the light emitting element 3. The height of the top surface 9A of the light shielding portion 9 relative to the first surface 1A is greater than the height of the top surface of the light emitting layer 6 relative to the first surface 1A.

[0084] In the embodiment of the present disclosure, the second-type semiconductor layer 7 includes a top surface 7A away from the base substrate 1, and the height of the top surface 9A of the shading portion 9 relative to the first surface 1A is greater than the height of the top surface 7A of the second-type semiconductor layer 7 relative to the first surface 1A.

[0085] In an embodiment of the present disclosure, the first-type semiconductor layer 5 includes a bottom surface 5A close to the substrate 1, the shading portion 9 includes a bottom surface 9B close to the substrate 1, and the height of the bottom surface 9B of the shading portion 9 relative to the first surface 1A is less than the height of the bottom surface 5A of the first-type semiconductor layer 5 relative to the first surface 1A.

[0086] In the embodiment of the present disclosure, the bottom surface 9B of the light shielding portion 9 contacts the first surface 1A.

[0087] In the embodiment of the present disclosure, the first-type semiconductor layer 5 includes a bottom surface 5A close to the base substrate 1, and the light-emitting element 3 includes a side wall 3A connecting the top surface 7A of the second-type semiconductor layer 7 and the bottom surface 5A of the first-type semiconductor layer 5, and the side wall 3A of the light-emitting element 3 is inclined relative to the bottom surface 5A of the first-type semiconductor layer 5.

[0088] In the embodiment of the present disclosure, the shading portion 9 includes a bottom surface 9B close to the base substrate 1 and a side wall 9C connecting the top surface 9A and the bottom surface of the shading portion 9, and the side wall 9C of the shading portion 9 is inclined relative to the bottom surface 9B of the shading portion 9.

[0089] Figure 3 The figure schematically shows the tilt angle of the light emitting element according to the embodiment of the present disclosure.

[0090] In the embodiments of the present disclosure, the side wall 3A of the light emitting element 3 is inclined at a first angle ∠A relative to the bottom surface 5A of the first semiconductor layer 5, and the first angle ∠A is less than or equal to 65°; and / or the side wall 9C of the light shielding portion 9 is inclined at a second angle ∠B relative to the bottom surface 9B of the light shielding portion 9, and the second angle ∠B is less than or equal to 65°. The inventors have found that if the LED is etched into a vertical structure, due to the relatively large refractive index of GaN, the critical angle in the air is only 25 degrees, that is, the light within 25° oscillates repeatedly in the structure and cannot become an effective light emitting device to display brightness. Figure 3 As shown, the light emitting element forms a regular trapezoid, and the first angle ∠A is less than or equal to 65°, which is conducive to breaking through the limitation of the critical angle and allowing the light to come out more effectively.

[0091] Continue to refer to Figure 2, the display panel further includes: a first insulating layer 10 located between the second-type semiconductor layer 7 and the layer where the second electrode 8 is located; and a plurality of openings 10C located in the first insulating layer 10; and, the first insulating layer 10 includes a first portion 10A and a second portion 10B, the first portion 10A of the first insulating layer 10 covers a portion of the top surface 7A of the second-type semiconductor layer 7, the opening 10C exposes another portion of the top surface 7A of the second-type semiconductor layer 7, and the second portion 10B of the first insulating layer 10 covers the side wall 3A of the light-emitting element 3. For example, the first insulating layer 10 can be made of an inorganic material with a gradient refractive index, such as silicon nitride or silicon oxide, and the refractive index of the first insulating layer 10 satisfies the gradient from the refractive index of GaN to the refractive index of air. Specifically, the refractive index of GaN is 2.4, the refractive index of air is 1.0, and the refractive index of the first insulating layer 10 can be between 2.4 and 1.0 to satisfy the gradient from the refractive index of GaN to the refractive index of air.

[0092] In the embodiment of the present disclosure, the second electrode 8 includes a first electrode portion 8A, a second electrode portion 8B and a third electrode portion 8C, the first electrode portion 8A covers the first portion 10A of the first insulating layer 10, the second electrode portion 8B covers the second portion 10B of the first insulating layer 10, and the third electrode portion 8C is located in the opening 10C; and the shading portion 9 is in contact with at least the first electrode portion 4 of the second electrode 8. Since the second electrode of at least one light-emitting element is connected together by the shading portion having good conductivity, the voltage drop (IR drop) in the display substrate can be effectively reduced.

[0093] Figure 4 The diagram schematically shows the spacing between the light shielding portion and the first insulating layer projected on the base substrate according to an embodiment of the present disclosure.

[0094] like Figure 4 As shown, an orthographic projection S1 of the light shielding portion 9 on the base substrate 1 is spaced apart from an orthographic projection S2 of the second portion 10B of the first insulating layer 10 on the base substrate 1 .

[0095] Figure 5 The diagram schematically shows the spacing between the light shielding portion and the first insulating layer projected on the base substrate according to an embodiment of the present disclosure.

[0096] In the embodiments of the present disclosure, Figure 5 As shown, the shading portion 9 further includes a first sub-shading portion 9D and a second sub-shading portion 9E. The first sub-shading portion 9D contacts the first electrode portion 8A of the second electrode 8, and the second sub-shading portion 9E contacts the second electrode portion 8B of the second electrode 8.

[0097] Reference Figure 5, the orthographic projection of the second sub-light shielding portion 9E on the base substrate 1 at least partially overlaps with the orthographic projection of the second electrode portion 8B of the second electrode 8 on the base substrate 1; and / or, the orthographic projection of the second sub-light shielding portion 9E on the base substrate 1 at least partially overlaps with the orthographic projection of the second portion 10B of the first insulating layer 10 on the base substrate 1. The second electrode 8 includes a top surface 8D away from the base substrate 1, and the height of the top surface 9A of the light shielding portion 9 relative to the first surface 1A is greater than the height of the top surface 8D of the second electrode 8 relative to the first surface 1A.

[0098] According to the embodiment of the present disclosure, the contact area between the light shielding portion and the second electrode is larger, and the light shielding portion and the second electrode are not in contact only at the opening left by the insulating layer in the light emitting direction, which can more effectively reduce the voltage drop in the display substrate.

[0099] At present, a comprehensive comparison of various display technologies shows that, on the one hand, LED display has high power consumption. In order to reduce its power consumption level, it is necessary to study its power consumption composition. Its static mini LED display power consumption is composed of TFT power consumption (transistor power consumption), IR drop power consumption (voltage drop power consumption) and LED power consumption. In order to reduce the power consumption loss of the display, it is necessary to increase the power consumption ratio of effective LED to improve chip efficiency and ensure its photoelectric conversion performance. On the other hand, Figure 8 As shown, when using a flip chip, congestion and blockage easily occur due to current expansion, poor light spot uniformity, poor current controllability, and an asymmetric light pattern that is difficult to control.

[0100] Figure 6 A cross-sectional view of a display substrate according to an embodiment of the present disclosure is schematically shown.

[0101] like Figure 6 As shown, at least one light-emitting element 3 includes a first sub-light-emitting element 11 and a second sub-light-emitting element 12, and the first sub-light-emitting element 11 and the second sub-light-emitting element 12 are stacked in a direction perpendicular to the first surface 1A of the substrate 1, and the first surface 1A is the surface of the substrate 1 facing the light-emitting element 3.

[0102] According to the embodiment of the present disclosure, the first sub-light-emitting element 11 includes a first electrode 4, a first-type semiconductor layer 5, a light-emitting layer 6 and a second-type semiconductor layer 7. The first electrode 4 is electrically connected to the conductive pattern 2. The first-type semiconductor layer 5 of the first sub-light-emitting element 11 is located on the side of the first electrode 4 away from the substrate 1. The light-emitting layer 6 of the first sub-light-emitting element 11 is located on the side of the first-type semiconductor layer 5 of the first sub-light-emitting element 11 away from the substrate 1. The second-type semiconductor layer 7 of the first sub-light-emitting element 11 is located on the side of the light-emitting layer 6 of the first sub-light-emitting element 11 away from the substrate 1.

[0103] According to the embodiment of the present disclosure, the second sub-light-emitting element 12 includes a first-type semiconductor layer 5, a light-emitting layer 6, a second-type semiconductor layer 7 and a second electrode 8, the first-type semiconductor layer 5 of the second sub-light-emitting element 12 is located on the side of the second-type semiconductor layer 7 of the first sub-light-emitting element 11 away from the substrate 1, the light-emitting layer 6 of the second sub-light-emitting element 12 is located on the side of the first-type semiconductor layer 5 of the second sub-light-emitting element 12 away from the substrate 1, the second-type semiconductor layer 7 of the second sub-light-emitting element 12 is located on the side of the light-emitting layer 6 of the second sub-light-emitting element 12 away from the substrate 1, and the second electrode 8 is located on the side of the second-type semiconductor layer 7 of the second sub-light-emitting element 12 away from the substrate 1; and, the second-type semiconductor layer 7 of the first sub-light-emitting element 11 and the first-type semiconductor layer 5 of the second sub-light-emitting element 12 are electrically connected via a first bonding layer 13.

[0104] According to an embodiment of the present disclosure, the light-emitting layer 6 of the second sub-light-emitting element 12 includes a top surface 12A away from the substrate 1, the shading portion 9 includes a top surface 9A away from the substrate 1, and the height of the top surface 9A of the shading portion 9 relative to the first surface 1A is greater than the height of the top surface 12A of the light-emitting layer 6 of the second sub-light-emitting element 12 relative to the first surface 1A; and / or, the light-emitting layer 6 of the first sub-light-emitting element 11 includes a bottom surface 11B close to the substrate 1, the shading portion 9 includes a bottom surface 9B close to the substrate 1, and the height of the bottom surface 9B of the shading portion 9 relative to the first surface 1A is less than the height of the bottom surface 11B of the light-emitting layer 6 of the first sub-light-emitting element 11 relative to the first surface 1A.

[0105] According to the embodiments of the present disclosure, the second-type semiconductor layer 7 of the second sub-light-emitting element 12 includes a top surface 12B away from the base substrate 1, and the height of the top surface 9A of the shading portion 9 relative to the first surface 1A is greater than the height of the top surface 12B of the second-type semiconductor layer 7 of the second sub-light-emitting element 12 relative to the first surface 1A; and / or, the first-type semiconductor layer 5 of the first sub-light-emitting element 11 includes a bottom surface 11A close to the base substrate 1, and the height of the bottom surface 9B of the shading portion 9 relative to the first surface 1A is less than the height of the bottom surface 11A of the first-type semiconductor layer 5 of the first sub-light-emitting element 11 relative to the first surface 1A.

[0106] According to the embodiment of the present disclosure, bottom surface 9B of light shielding portion 9 contacts first surface 1A.

[0107] According to the embodiment of the present disclosure, the light-emitting element 3 includes a side wall 3A connecting the top surface 12B of the second-type semiconductor layer 7 of the second sub-light-emitting element 12 and the bottom surface 11A of the first-type semiconductor layer 5 of the first sub-light-emitting element 11, and the side wall 3A of the light-emitting element 3 is inclined relative to the bottom surface 11A of the first-type semiconductor layer 5 of the first sub-light-emitting element 11.

[0108] According to the embodiment of the present disclosure, the shading portion 9 includes a bottom surface 9B close to the base substrate 1 and a side wall connecting the top surface 9A and the bottom surface of the shading portion 9 , and the side wall 9C of the shading portion 9 is inclined relative to the bottom surface 9B of the shading portion 9 .

[0109] Figure 7 The figure schematically shows a shape diagram of a first bonding layer according to an embodiment of the present disclosure.

[0110] In the actual manufacturing process, due to process and other reasons, the first light-emitting sub-element epitaxy, the second light-emitting sub-element epitaxy and the etching deviation of the first bonding layer are different, and the first bonding layer 13 will shrink inwards. Figure 7 The first bonding layer 13 includes a bottom surface 13A of the second-type semiconductor layer 7 facing the first sub-light-emitting element 11, a top surface 13B of the first-type semiconductor layer 5 facing the second sub-light-emitting element 12, and a side wall 13C connecting the bottom surface and the top surface of the first bonding layer 13; the side wall 13C of the first bonding layer 13 is retracted inwardly relative to the side wall of the second-type semiconductor layer 7 of the adjacent first sub-light-emitting element 11, and / or, the side wall 13A of the first bonding layer 13 is retracted inwardly relative to the side wall of the first-type semiconductor layer 5 of the adjacent second sub-light-emitting element 12.

[0111] Return to reference Figure 2 and Figure 5 The display substrate 100 further includes a lens 14 located on the base substrate 1 . The lens 14 is located on a side of the second electrode 8 away from the base substrate 1 . The orthographic projection of the lens 14 on the base substrate 1 covers the orthographic projection of the opening 10C on the base substrate 1 .

[0112] It should be noted that, in some embodiments, the orthographic projection of the lens 14 on the base substrate 1 and the orthographic projection of the second portion 10B of the first insulating layer 10 on the base substrate 1 at least partially overlap; and / or, the orthographic projection of the lens 14 on the base substrate 1 and the orthographic projection of the second portion 8B of the second electrode 8 on the base substrate 1 at least partially overlap. The orthographic projection of the lens 14 on the base substrate 1 and the orthographic projection of the light shielding portion 9 on the base substrate 1 at least partially overlap.

[0113] The first sub-light emitting element in the light emitting element is stacked with the second sub-light emitting element, and the first-type semiconductor layer in the sub-light emitting element is stacked with the second-type semiconductor layer. The current has a higher expansibility and a better degree of recombination of electrons and holes, and it can be obtained, for example Fig. 9 As shown, a more uniform light pattern.

[0114] In some embodiments, reference Fig.34 The display panel includes a display substrate 100, a cover plate 15 disposed opposite to the display substrate 100, and an adhesive layer 16 located between the display substrate 100 and the cover plate 15. Fig.34As shown, the side of the cover plate 15 close to the light emitting element is the first bottom surface of the cover plate 15, the point at which the lens 14 is farthest from the base substrate 1 is the vertex of the lens 14, and the distance between the first bottom surface and the first surface 1A of the base substrate 1 is greater than the distance between the vertex of the lens 14 and the first surface 1A of the base substrate 1. The materials used for the cover plate 15 include but are not limited to glass, silicon, etc., and the materials of the adhesive layer 16 between the cover plate 15 and the display substrate 100 include but are not limited to OCR (Optical Clear Resin) glue, OCA (Optically Clear Adhesive) glue, etc.

[0115] Fig.10 FIG. 1 is a flow chart of a method for preparing a display substrate according to an embodiment of the present disclosure. Fig.10 As shown, the method may include steps S1010 to S1050.

[0116] In step S1010, a base substrate 1 is provided, and a plurality of conductive patterns 2 are formed on the base substrate 1. The material of the base substrate 1 may include but is not limited to glass, quartz, plastic, silicon, polyimide, and the like.

[0117] In step S1020, the light emitting element epitaxial wafer is bonded to the base substrate on which a plurality of conductive patterns 2 are formed. Fig.11 As shown, the light-emitting element epitaxial wafer includes a first electrode epitaxial 4P, a first-type semiconductor epitaxial 5P, a light-emitting layer epitaxial 6P, and a second-type semiconductor epitaxial 7P, wherein the light-emitting layer epitaxial 6P is located between the first-type semiconductor epitaxial 5P and the second-type semiconductor epitaxial 7P. The light-emitting element epitaxial wafer is bonded to a substrate 1 having a plurality of conductive patterns formed thereon through a bonding layer 16. Among them, the first-type semiconductor epitaxial can be N-type gallium nitride (GaN), denoted as N-GaN, and the second-type semiconductor epitaxial can be P-type gallium nitride (GaN), denoted as P-GaN. The bonding layer 16 material can be made of metal oxide, preferably, the material can be transparent materials such as ITO (indium tin oxide), IZO (indium tin oxide), and ZnO (zinc oxide). For example, the bonding layer 16 on the P-GaN side can use ITO (indium tin oxide). The bonding layer 16 can be a whole surface or patterned.

[0118] In step S1030, the light emitting element epitaxial wafer is patterned to form a plurality of light emitting elements 3 arranged in an array and spaced apart from each other on the substrate. Fig.12As shown, at least one light-emitting element 3 includes a first electrode 4, a first-type semiconductor layer 5, a light-emitting layer 6 and a second-type semiconductor layer 7, the first electrode 4 is electrically connected to the conductive pattern, the first-type semiconductor layer 5 is located on a side of the first electrode 4 away from the substrate 1, the light-emitting layer 6 is located on a side of the first-type semiconductor layer 5 away from the substrate 1, and the second-type semiconductor layer 7 is located on a side of the light-emitting layer 6 away from the substrate 1;

[0119] In some embodiments, the sidewall of the light emitting element 3 is inclined at a first angle relative to the bottom surface of the first-type semiconductor layer 5 , and the first angle is less than or equal to 65°.

[0120] In step S1031, a first insulating layer 10 is deposited on the second semiconductor layer 7; for example, the material of the first insulating layer 10 may include but is not limited to SiN (silicon nitride) or SiOn (silicon oxide) materials, and the refractive index of the first insulating layer satisfies the gradual change from the refractive index of GaN to the refractive index of air 2.4 to 1.0. The first insulating layer 10 covers the sidewalls and the top of the light emitting element 3.

[0121] In step S1032, the first insulating layer 10 is punched. Fig.13 As shown, the first insulating layer 10 includes a first portion 10A and a second portion 10B, the first portion 10A of the first insulating layer 10 covers a portion of the top surface of the second-type semiconductor layer 7, the opening 10C exposes another portion of the top surface of the second-type semiconductor layer 7, and the second portion 10B of the first insulating layer 10 covers the side wall of the light-emitting element 3. The orthographic projection of the light-shielding portion 9 on the base substrate is spaced apart from the orthographic projection of the second portion 10B of the first insulating layer 10 on the base substrate.

[0122] In step S1040, a second electrode 8 is formed on a side of the second-type semiconductor layer 7 away from the base substrate 1. Fig.14 As shown, the second electrode 8 includes a first electrode portion 8A, a second electrode portion 8B and a third electrode portion 8C, and the light shielding portion 9 is in contact with at least the first electrode portion 8A of the second electrode 8. The first electrode portion 8A of the second electrode 8 covers the first portion 10A of the first insulating layer 10, the second electrode portion 8B covers the second portion 10B of the first insulating layer 10, and the third electrode portion 8C is located in the opening 10C.

[0123] In step S1050, a conductive light shielding portion is formed in the gaps between the plurality of light emitting elements, and the light shielding portion is electrically connected to the second electrode. Fig.15 As shown, the light shielding portion 9 is in contact with at least the first electrode portion 8A of the second electrode.

[0124] In some embodiments, the shading portion 9 further includes a first sub-shading portion and a second sub-shading portion, the first sub-shading portion contacts the first electrode portion 8A of the second electrode 8, and the second sub-shading portion contacts the second electrode portion 8B of the second electrode 8. The orthographic projection of the second sub-shading portion on the base substrate 1 at least partially overlaps with the orthographic projection of the second electrode portion 8B of the second electrode 8 on the base substrate 1; the second electrode 8 includes a top surface away from the base substrate, and the height of the top surface of the shading portion 9 relative to the first surface 1A is greater than the height of the top surface of the second electrode 8 relative to the first surface 1A. Among them, the material of the shading portion 9 is a metal material with good conductivity, including but not limited to copper, aluminum, tin or other alloy materials.

[0125] For example, a dry etching method may be used to drill holes in the first insulating layer 10 .

[0126] In some embodiments, an orthographic projection of the second sub-light-shielding portion on the base substrate 1 at least partially overlaps with an orthographic projection of the second portion 10B of the first insulating layer 10 on the base substrate 1 .

[0127] In some embodiments, the method further comprises step S1060, forming a lens on the plurality of light emitting elements. Figure 2 The lens is semicircular, and the lens aperture is determined by the number and spacing of pixels. The material can be inorganic materials such as SiN, SiO, etc., or organic resin materials, etc.

[0128] Fig.16 is a flow chart of a method for preparing a display substrate according to an embodiment of the present disclosure.

[0129] like Fig.16 As shown, the method for preparing a display substrate according to an embodiment of the present disclosure includes steps S1610 to S16110.

[0130] In step S1610, a second sub-light emitting element epitaxial structure is formed on the second substrate 17. Fig.17 As shown, the second sub-light-emitting element epitaxial structure may include a first-type semiconductor layer epitaxy 5P, a light-emitting layer epitaxy 6P, and a second-type semiconductor layer epitaxy 7P. The light-emitting layer epitaxy 6P is located between the first-type semiconductor layer epitaxy 5P and the second-type semiconductor layer epitaxy 7P. The material of the second substrate 17 may include but is not limited to glass, quartz, plastic, silicon, polyimide, etc. The first-type semiconductor layer epitaxy 5P may be N-type gallium nitride (GaN), denoted as N-GaN, and the second-type semiconductor layer epitaxy 7P may be P-type gallium nitride (GaN), denoted as P-GaN.

[0131] In some embodiments, the second sub-light emitting element epitaxial structure may further include a buffer semiconductor layer 18 .

[0132] In step S1620, if Fig.18 As shown, a second sub-bonding layer 19 is formed on the side of the second sub-light-emitting element epitaxial structure away from the second substrate 17. The material of the second sub-bonding layer 19 can be a metal oxide such as ITO (indium tin oxide) and IZO (indium tin oxide). For example, the p-GaN side bonding layer material is ITO (indium tin oxide).

[0133] In step S1630, the second sub-light emitting element epitaxial structure and the second sub-bonding layer 19 are patterned to form the second sub-light emitting element 12. Fig.19 As shown, the second sub-light-emitting element 12 includes a second-type semiconductor layer 7, a light-emitting layer 6 and a first-type semiconductor layer 5. The second-type semiconductor layer 7 of the second sub-light-emitting element 12 is located on the second substrate 17, the light-emitting layer 6 of the second sub-light-emitting element 12 is located on the side of the second-type semiconductor layer 7 of the second sub-light-emitting element 12 away from the second substrate 17, and the first-type semiconductor layer 5 of the second sub-light-emitting element 12 is located on the side of the light-emitting layer 6 of the second sub-light-emitting element 12 away from the second substrate 17.

[0134] In step S1640 , an epitaxial structure of a first sub-light emitting element 11 is formed on the first substrate 20 .

[0135] Step S1640 specifically includes steps S1641 to S1644.

[0136] In step S1641, a first sub-light emitting element epitaxial structure is formed on the first temporary substrate 21;

[0137] In some embodiments, the epitaxial structure of the first sub-light-emitting element may be the same as the epitaxial structure of the second sub-light-emitting element.

[0138] In step S1642, a first temporary bonding layer 22 is formed on the first sub-light emitting element epitaxial structure. Fig. 20 As shown, the first temporary bonding layer 22 is located on a side of the first sub-light emitting element epitaxial structure away from the first temporary substrate 21. The material of the first temporary bonding layer 22 may include but is not limited to SiOx (silicon oxide) and the like.

[0139] In step S1643, the first sub-light emitting element epitaxial structure is bonded to the first substrate 20 via the first temporary bonding layer 22. Fig.21 As shown, after the first sub-light emitting element epitaxial structure and the first substrate 20 are bonded, the first substrate 20 is located on the side of the first sub-light emitting element epitaxial structure away from the first temporary substrate 21. The material of the first substrate 20 may include but is not limited to glass, quartz, plastic, silicon, polyimide, etc.

[0140] In step S1644, if Fig. 22As shown, the first temporary substrate 21 is removed. It should be noted that, in some embodiments, when the first sub-light emitting element epitaxial structure includes a buffer semiconductor layer, the buffer semiconductor layer also needs to be removed.

[0141] In step S1650, if Fig.23 As shown, a first sub-bonding layer 23 is formed on the side of the first sub-light-emitting element epitaxial structure away from the first substrate 20. The material of the first sub-bonding layer 23 can be a metal oxide such as ITO (indium tin oxide) and IZO (indium tin oxide). For example, the p-GaN side bonding layer material is ITO (indium tin oxide).

[0142] In step S1660, if Fig.24 As shown, the second sub-light-emitting element 12 and the first sub-light-emitting element epitaxial structure 24 are bonded via the first sub-bonding layer 23 and the second sub-bonding layer 19 .

[0143] In step S1670, if Fig.25 As shown, the first substrate is removed. It should be noted that when the first substrate is removed, the first temporary bonding layer 22 also needs to be removed.

[0144] In step S1680, the first sub-light emitting element epitaxial structure and the first sub-bonding layer 23 are patterned to form the first sub-light emitting element 11. Fig.26 As shown, the first sub-light-emitting element 11 includes a second-type semiconductor layer 7, a light-emitting layer 6 and a first-type semiconductor layer 5. The second-type semiconductor layer 7 of the first sub-light-emitting element 11 is located on the first sub-bonding layer 23, the light-emitting layer 6 of the first sub-light-emitting element 11 is located on the side of the second-type semiconductor layer 7 of the first sub-light-emitting element 11 away from the second substrate 17, and the first-type semiconductor layer 5 of the first sub-light-emitting element 11 is located on the side of the light-emitting layer 6 of the first sub-light-emitting element 11 away from the second substrate 17.

[0145] In step S1690, the second substrate 17 formed with the first sub-light emitting element 11 and the second sub-light emitting element 12 is bonded to the base substrate 1, and the second substrate 17 is removed to form a plurality of light emitting elements 3 on the base substrate 1. Fig. 27 As shown, at least one light-emitting element 3 includes a first sub-light-emitting element 11 and a second sub-light-emitting element 12, and the first sub-light-emitting element 11 and the second sub-light-emitting element 12 are stacked in a direction perpendicular to the first surface 1A of the substrate 1, and the first surface 1A is the surface of the substrate 1 facing the light-emitting element.

[0146] In step S16100, if Fig.29 As shown, a second electrode 8 is formed on a side of the second-type semiconductor layer 7 of the second sub-light-emitting element 12 away from the base substrate 1 .

[0147] In some embodiments, before step S16100, it also includes making an insulating layer 10, such as Fig.28 As shown, the insulating layer 10 includes a first portion 10A, a second portion 10B and an opening 10C, the first portion 10A of the insulating layer 10 covers a portion of the top surface 7A of the second-type semiconductor layer 7 of the first sub-light-emitting element 11, the opening 10C exposes another portion of the top surface 7A of the second-type semiconductor layer 7 of the first sub-light-emitting element 11, and the second portion 10B of the insulating layer 10 covers the side walls of the first sub-light-emitting element 11 and the second sub-light-emitting element 12.

[0148] In step S16110, if Fig.30 As shown, a conductive light shielding portion 9 is formed in the gaps between the plurality of light emitting elements 3 , and the light shielding portion 9 is electrically connected to the second electrode 8 .

[0149] Fig.31 is a flow chart of a method for preparing a display substrate according to an embodiment of the present disclosure.

[0150] like Fig.31 As shown, the method for preparing a display substrate according to an embodiment of the present disclosure includes steps S3110 to S3190.

[0151] In step S3110, an epitaxial structure of the second sub-light emitting element 12 is formed on the second substrate 17; the specific content is the same as step S1610 in the method for preparing the display substrate according to the embodiment of the present disclosure, and will not be repeated here.

[0152] In step S3120, a second sub-bonding layer 19 is formed on the side of the epitaxial structure of the second sub-light emitting element 12 away from the second substrate 17; the specific content is the same as step S1620 in the method for preparing the display substrate according to the embodiment of the present disclosure, and will not be repeated here.

[0153] In step S3130, a first sub-light-emitting element epitaxial structure is formed on the first substrate 20; the specific content is the same as step S1640 in the method for preparing a display substrate according to an embodiment of the present disclosure, and will not be repeated here.

[0154] In step S3140, a first sub-bonding layer 23 is formed on a side of the first sub-light-emitting element epitaxial structure away from the first substrate 20; the specific content is the same as step S1650 in the method for preparing the display substrate according to the embodiment of the present disclosure, and will not be repeated here.

[0155] In step S3150, the second sub-light emitting element epitaxial structure 25 and the first sub-light emitting element epitaxial structure 24 are bonded through the first sub-bonding layer 23 and the second sub-bonding layer 19; Fig.32As shown, different from the embodiment, the second sub-light emitting element epitaxial structure is directly bonded to the first sub-light emitting element epitaxial structure without being patterned. According to the actual process and production conditions, in some embodiments, this bonding method can improve the bonding yield.

[0156] In step S3160, the first substrate 20 is removed; the specific content is the same as step S1670 in the method for preparing a display substrate according to an embodiment of the present disclosure, and will not be described in detail here.

[0157] In step S3170, the second substrate 17 having the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure is bonded to the base substrate 1, and the second substrate 17 is removed, and the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure are patterned to form a plurality of light-emitting elements 3 on the base substrate. Fig.33 As shown, at least one light-emitting element 3 includes a first sub-light-emitting element 11 and a second sub-light-emitting element 12, and the first sub-light-emitting element 11 and the second sub-light-emitting element 12 are stacked in a direction perpendicular to the first surface 1A of the substrate 1, and the first surface 1A is the surface of the substrate 1 facing the light-emitting element.

[0158] It should be noted that, in some embodiments, the epitaxial structure of the second sub-light-emitting element and the epitaxial structure of the first sub-light-emitting element are patterned, and the side walls of the first sub-light-emitting element and the second sub-light-emitting element formed have the same inclination angle and the same direction, and the extension line of the side wall of the first sub-light-emitting element coincides with the side wall of the second sub-light-emitting element.

[0159] In step S3180, a second electrode 8 is formed on a side of the second sub-light emitting element 12 away from the base substrate 1; the specific content is the same as step S16100 in the method for preparing the display substrate according to the embodiment of the present disclosure, and will not be repeated here.

[0160] In step S3190, a conductive shading portion 9 is formed in the gaps between the plurality of light-emitting elements 3, and the shading portion 9 is electrically connected to the second electrode 8; the specific content is the same as step S16110 in the method for preparing the display substrate according to the embodiment of the present disclosure, and will not be repeated here.

[0161] It should be understood that the display device according to some exemplary embodiments of the present disclosure has all the features and advantages of the above-mentioned display substrate, and these features and advantages can be referred to the above description of the display substrate, which will not be repeated here.

[0162] As used herein, the terms "substantially," "approximately," "approximately," and other similar terms are used as terms of approximation rather than as terms of degree, and they are intended to account for the inherent deviations in measured or calculated values ​​that would be recognized by one of ordinary skill in the art. Taking into account factors such as process fluctuations, measurement problems, and errors associated with the measurement of a particular quantity (i.e., limitations of the measurement system), "approximately" or "approximately" as used herein include the stated value and mean that the particular value is within an acceptable range of deviation as determined by one of ordinary skill in the art. For example, "approximately" can mean within one or more standard deviations, or within ±10% or ±5% of the stated value.

[0163] Although some embodiments according to the general inventive concept of the present disclosure have been illustrated and described, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the general inventive concept of the present disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. A display substrate, characterized in that: The display substrate comprises: substrate substrate; a plurality of conductive patterns located on the substrate; a plurality of light-emitting elements located on the base substrate, the plurality of light-emitting elements being arranged in an array and spaced apart from each other on the base substrate, at least one of the light-emitting elements comprising a first electrode, a first-type semiconductor layer, a light-emitting layer, a second-type semiconductor layer, and a second electrode, the first electrode being electrically connected to the conductive pattern, the first-type semiconductor layer being located on a side of the first electrode away from the base substrate, the light-emitting layer being located on a side of the first-type semiconductor layer away from the base substrate, the second-type semiconductor layer being located on a side of the light-emitting layer away from the base substrate, and the second electrode being located on a side of the second-type semiconductor layer away from the base substrate; and A conductive light shielding portion is located on the base substrate, wherein the light shielding portion is located in a gap between two adjacent light emitting elements, and the light shielding portion is electrically connected to the second electrode.

2. The display substrate according to claim 1, wherein: The light emitting layer includes a top surface away from the base substrate, the light shielding portion includes a top surface away from the base substrate, and the base substrate includes a first surface facing the light emitting element; and A height of a top surface of the light shielding portion relative to the first surface is greater than a height of a top surface of the light emitting layer relative to the first surface.

3. The display substrate according to claim 2, wherein: The second-type semiconductor layer includes a top surface away from the base substrate, and a height of a top surface of the light shielding portion relative to the first surface is greater than a height of a top surface of the second-type semiconductor layer relative to the first surface.

4. The display substrate according to claim 2 or 3, wherein: The first-type semiconductor layer includes a bottom surface close to the base substrate, the shading portion includes a bottom surface close to the base substrate, and a height of the bottom surface of the shading portion relative to the first surface is smaller than a height of the bottom surface of the first-type semiconductor layer relative to the first surface.

5. The display substrate according to claim 4, wherein: A bottom surface of the light shielding portion contacts the first surface.

6. The display substrate according to any one of claims 1 to 3 and 5, wherein: The first-type semiconductor layer includes a bottom surface close to the base substrate, the light-emitting element includes a side wall connecting the top surface of the second-type semiconductor layer and the bottom surface of the first-type semiconductor layer, and the side wall of the light-emitting element is inclined relative to the bottom surface of the first-type semiconductor layer.

7. The display substrate according to claim 6, wherein: The light shielding portion includes a bottom surface close to the base substrate and a side wall connecting the top surface and the bottom surface of the light shielding portion, and the side wall of the light shielding portion is inclined relative to the bottom surface of the light shielding portion.

8. The display substrate according to claim 7, wherein: The side wall of the light emitting element is inclined at a first angle relative to the bottom surface of the first-type semiconductor layer, and the first angle is less than or equal to 65°; and / or, The side wall of the light shielding portion is inclined at a second angle relative to the bottom surface of the light shielding portion, and the second angle is less than or equal to 65°.

9. The display substrate according to any one of claims 1 to 3, 5, 7 and 8, wherein: The display panel further includes: a first insulating layer located between the second-type semiconductor layer and the layer where the second electrode is located; and a plurality of openings located in the first insulating layer; and The first insulating layer includes a first portion and a second portion, the first portion of the first insulating layer covers a portion of the top surface of the second-type semiconductor layer, the opening exposes another portion of the top surface of the second-type semiconductor layer, and the second portion of the first insulating layer covers the side wall of the light-emitting element.

10. The display substrate according to claim 9, wherein: The second electrode includes a first electrode portion, a second electrode portion and a third electrode portion, the first electrode portion covers a first portion of the first insulating layer, the second electrode portion covers a second portion of the first insulating layer, and the third electrode portion is located in the opening; as well as The light shielding portion is in contact with at least the first electrode portion of the second electrode.

11. The display substrate according to claim 10, wherein: An orthographic projection of the light shielding portion on the base substrate is spaced apart from an orthographic projection of the second portion of the first insulating layer on the base substrate.

12. The display substrate according to claim 11, wherein: The light shielding portion includes a first sub-light shielding portion and a second sub-light shielding portion, the first sub-light shielding portion is in contact with the first electrode portion of the second electrode, and the second sub-light shielding portion is in contact with the second electrode portion of the second electrode.

13. The display substrate according to claim 12, wherein: The orthographic projection of the second sub-light shielding portion on the base substrate at least partially overlaps with the orthographic projection of the second electrode portion of the second electrode on the base substrate; and / or, An orthographic projection of the second sub-light-shielding portion on the base substrate at least partially overlaps with an orthographic projection of the second portion of the first insulating layer on the base substrate.

14. The display substrate according to claim 13, wherein: The second electrode includes a top surface away from the base substrate, and a height of a top surface of the light shielding portion relative to the first surface is greater than a height of a top surface of the second electrode relative to the first surface.

15. The display substrate according to any one of claims 1 to 3, 5, 7 and 8, wherein: At least one of the light-emitting elements comprises a first sub-light-emitting element and a second sub-light-emitting element, wherein the first sub-light-emitting element and the second sub-light-emitting element are stacked in a direction perpendicular to a first surface of the substrate, and the first surface is a surface of the substrate facing the light-emitting element; The first sub-light emitting element comprises a first electrode, a first-type semiconductor layer, a light emitting layer and a second-type semiconductor layer, the first electrode is electrically connected to the conductive pattern, the first-type semiconductor layer of the first sub-light emitting element is located on a side of the first electrode away from the base substrate, the light emitting layer of the first sub-light emitting element is located on a side of the first-type semiconductor layer of the first sub-light emitting element away from the base substrate, and the second-type semiconductor layer of the first sub-light emitting element is located on a side of the light emitting layer of the first sub-light emitting element away from the base substrate; The second sub-light emitting element comprises a first-type semiconductor layer, a light emitting layer, a second-type semiconductor layer and a second electrode, the first-type semiconductor layer of the second sub-light emitting element is located on a side of the second-type semiconductor layer of the first sub-light emitting element away from the base substrate, the light emitting layer of the second sub-light emitting element is located on a side of the first-type semiconductor layer of the second sub-light emitting element away from the base substrate, the second-type semiconductor layer of the second sub-light emitting element is located on a side of the light emitting layer of the second sub-light emitting element away from the base substrate, and the second electrode is located on a side of the second-type semiconductor layer of the second sub-light emitting element away from the base substrate; as well as The second-type semiconductor layer of the first sub-light emitting element and the first-type semiconductor layer of the second sub-light emitting element are electrically connected via a first bonding layer.

16. The display substrate according to claim 15, wherein: The light-emitting layer of the second sub-light-emitting element includes a top surface away from the base substrate, the light-shielding portion includes a top surface away from the base substrate, and the height of the top surface of the light-shielding portion relative to the first surface is greater than the height of the top surface of the light-emitting layer of the second sub-light-emitting element relative to the first surface; and / or, The light-emitting layer of the first sub-light-emitting element includes a bottom surface close to the base substrate, the light-shielding portion includes a bottom surface close to the base substrate, and the height of the bottom surface of the light-shielding portion relative to the first surface is smaller than the height of the bottom surface of the light-emitting layer of the first sub-light-emitting element relative to the first surface.

17. The display substrate according to claim 16, wherein: The second-type semiconductor layer of the second sub-light emitting element includes a top surface away from the base substrate, and the height of the top surface of the light shielding portion relative to the first surface is greater than the height of the top surface of the second-type semiconductor layer of the second sub-light emitting element relative to the first surface; and / or, The first type semiconductor layer of the first sub-light emitting element includes a bottom surface close to the base substrate, and the height of the bottom surface of the shading portion relative to the first surface is smaller than the height of the bottom surface of the first type semiconductor layer of the first sub-light emitting element relative to the first surface.

18. The display substrate according to claim 17, wherein: A bottom surface of the light shielding portion contacts the first surface.

19. The display substrate according to claim 17 or 18, wherein: The light emitting element comprises a side wall connecting the top surface of the second type semiconductor layer of the second sub-light emitting element and the bottom surface of the first type semiconductor layer of the first sub-light emitting element, and the side wall of the light emitting element is inclined relative to the bottom surface of the first type semiconductor layer of the first sub-light emitting element.

20. The display substrate according to claim 19, wherein: The light shielding portion includes a bottom surface close to the base substrate and a side wall connecting the top surface and the bottom surface of the light shielding portion, and the side wall of the light shielding portion is inclined relative to the bottom surface of the light shielding portion.

21. The display substrate according to claim 20, wherein: The side wall of the light emitting element is inclined at a first angle relative to the bottom surface of the first-type semiconductor layer, and the first angle is less than or equal to 65°; and / or, The side wall of the light shielding portion is inclined at a second angle relative to the bottom surface of the light shielding portion, and the second angle is less than or equal to 65°.

22. The display substrate according to any one of claims 1-3, 5, 7-8 and 16-21, wherein: The first bonding layer includes a bottom surface of the second-type semiconductor layer facing the first sub-light-emitting element, a top surface of the first-type semiconductor layer facing the second sub-light-emitting element, and a side wall connecting the bottom surface and the top surface of the first bonding layer; and The sidewall of the first bonding layer is retracted inwardly relative to the sidewall of the second-type semiconductor layer of the adjacent first sub-light-emitting element, and / or the sidewall of the first bonding layer is retracted inwardly relative to the sidewall of the first-type semiconductor layer of the adjacent second sub-light-emitting element.

23. The display substrate according to any one of claims 1-3, 5, 7-8 and 16-21, wherein: The display substrate further comprises a lens located on the base substrate, the lens is located on a side of the second electrode away from the base substrate, and an orthographic projection of the lens on the base substrate covers an orthographic projection of the opening on the base substrate.

24. The display substrate according to claim 23, wherein: The orthographic projection of the lens on the base substrate and the orthographic projection of the second portion of the first insulating layer on the base substrate at least partially overlap; and / or, An orthographic projection of the lens on the base substrate and an orthographic projection of the second portion of the second electrode on the base substrate at least partially overlap.

25. The display substrate according to claim 23, wherein: The orthographic projection of the lens on the base substrate at least partially overlaps with the orthographic projection of the light shielding portion on the base substrate.

26. A display panel, characterized in that: The display panel comprises: The display substrate according to any one of claims 1 to 25; a cover plate disposed opposite to the display substrate; and An adhesive layer is located between the display substrate and the cover plate.

27. A method for preparing a display substrate, characterized in that: The preparation method comprises: forming a plurality of conductive patterns on a base substrate; Bonding the light emitting element epitaxial wafer to a substrate having a plurality of conductive patterns formed thereon; The light-emitting element epitaxial wafer is patterned to form a plurality of light-emitting elements distributed in an array and spaced apart from each other on the substrate, wherein at least one of the light-emitting elements comprises a first electrode, a first-type semiconductor layer, a light-emitting layer, and a second-type semiconductor layer, the first electrode is electrically connected to the conductive pattern, the first-type semiconductor layer is located on a side of the first electrode away from the substrate, the light-emitting layer is located on a side of the first-type semiconductor layer away from the substrate, and the second-type semiconductor layer is located on a side of the light-emitting layer away from the substrate; forming a second electrode on a side of the second-type semiconductor layer away from the base substrate; and A conductive light shielding portion is formed in a gap between the plurality of light emitting elements, and the light shielding portion is electrically connected to the second electrode.

28. A method for preparing a display substrate, characterized in that: The preparation method comprises: forming a second sub-light emitting element epitaxial structure on a second substrate; forming a second sub-bonding layer on a side of the second sub-light emitting element epitaxial structure away from the second substrate; Patterning the epitaxial structure of the second sub-light-emitting element and the second bonding layer to form a second sub-light-emitting element, wherein the second sub-light-emitting element comprises a second-type semiconductor layer, a light-emitting layer and a first-type semiconductor layer, the second-type semiconductor layer of the second sub-light-emitting element is located on the second substrate, the light-emitting layer of the second sub-light-emitting element is located on a side of the second-type semiconductor layer of the second sub-light-emitting element away from the first substrate, and the first-type semiconductor layer of the second sub-light-emitting element is located on a side of the light-emitting layer of the second sub-light-emitting element away from the first substrate; forming a first sub-light emitting element epitaxial structure on a first substrate; forming a first sub-bonding layer on a side of the first sub-light emitting element epitaxial structure away from the first substrate; Bonding the second sub-light emitting element and the first sub-light emitting element epitaxial structure through the first sub-bonding layer and the second sub-bonding layer; removing the first substrate; Patterning the first sub-light-emitting element epitaxial structure and the first sub-bonding layer to form a first sub-light-emitting element, wherein the first sub-light-emitting element comprises a second-type semiconductor layer, a light-emitting layer and a first-type semiconductor layer, the second-type semiconductor layer of the first sub-light-emitting element is located on the first sub-bonding layer, the light-emitting layer of the first sub-light-emitting element is located on a side of the second-type semiconductor layer of the first sub-light-emitting element away from the second substrate, and the first-type semiconductor layer of the first sub-light-emitting element is located on a side of the light-emitting layer of the first sub-light-emitting element away from the second substrate; and Bonding a second substrate having the first sub-light-emitting element and the second sub-light-emitting element formed thereon to a base substrate, and removing the second substrate to form a plurality of light-emitting elements on the base substrate, wherein at least one of the light-emitting elements comprises a first sub-light-emitting element and a second sub-light-emitting element, and the first sub-light-emitting element and the second sub-light-emitting element are stacked in a direction perpendicular to a first surface of the base substrate, and the first surface is a surface of the base substrate facing the light-emitting element; forming a second electrode on a side of the second-type semiconductor layer of the second light-emitting element away from the base substrate; and A conductive light shielding portion is formed in a gap between the plurality of light emitting elements, and the light shielding portion is electrically connected to the second electrode.

29. A method for preparing a display substrate, characterized in that: The preparation method comprises: forming a second sub-light emitting element epitaxial structure on a second substrate; forming a second sub-bonding layer on a side of the second sub-light emitting element epitaxial structure away from the second substrate; forming a first sub-light emitting element epitaxial structure on a first substrate; forming a first sub-bonding layer on a side of the first sub-light emitting element epitaxial structure away from the first substrate; Bonding the second sub-light-emitting element epitaxial structure to the first sub-light-emitting element epitaxial structure through the first sub-bonding layer and the second sub-bonding layer; removing the first substrate; Bonding a second substrate having the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure formed thereon to a base substrate, removing the second substrate, and patterning the second sub-light-emitting element epitaxial structure and the first sub-light-emitting element epitaxial structure to form a plurality of light-emitting elements on the base substrate, wherein at least one of the light-emitting elements comprises a first sub-light-emitting element and a second sub-light-emitting element, the first sub-light-emitting element and the second sub-light-emitting element are stacked in a direction perpendicular to a first surface of the base substrate, the first surface being a surface of the base substrate facing the light-emitting element; forming a second electrode on a side of the second light emitting element away from the base substrate; and A conductive light shielding portion is formed in a gap between the plurality of light emitting elements, and the light shielding portion is electrically connected to the second electrode.

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