Light-emitting substrate

Abstract

A light-emitting substrate, comprising: multiple light-emitting chips disposed on a base layer, each light-emitting chip comprising a first electrode, a second electrode, and a light-emitting main body connected between the first electrode and the second electrode, the second electrode being located at a side of the light-emitting main body distant from the main layer; a filling layer comprising at least one filling portion, the filling portion at least being located between two adjacent light-emitting chips, the filling portion being provided with a head end and a tail end which are arranged along a circumferential direction of the light-emitting main body, and the thickness of the filling portion decreasing gradually or in a step-like manner from the head end to the tail end; a first connecting electrode, at least part of the first connecting electrode being located in the base layer, an orthographic projection of the first connecting electrode onto a reference surface not overlapping or not completely overlapping with an orthographic projection of the light-emitting main body onto the reference surface, and the reference surface being a plane perpendicular to the thickness direction of the base layer; and an auxiliary electrode electrically connected to the second electrode, at least part of the auxiliary electrode being disposed on a surface of the filling portion distant from the base layer, and electrically connected to the first connecting electrode by means of the tail end of the filling portion.

Description

Light-emitting substrate Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a light-emitting substrate. Background Art

[0002] Micro-inorganic light-emitting diodes include MiniLED and MicroLED. MiniLED refers to light-emitting diode (LED) chips with a grain size of approximately 100 to 300 microns. MicroLED refers to LED chips with a grain size of less than 100 microns. MiniLED / MicroLED display devices offer advantages such as low power consumption, high brightness, high resolution, high color saturation, fast response, long life, and high efficiency. Furthermore, multiple Mini-LED / Micro-LED display devices can be seamlessly spliced ​​together to create ultra-large display products, which have broad application prospects in large-scale display areas such as command and monitoring centers, commercial centers, high-end conferences, and cinemas.

[0003] Summary of the Invention

[0004] The present disclosure provides a light-emitting substrate, comprising:

[0005] grassroots;

[0006] a plurality of light-emitting chips disposed on the base layer, the light-emitting chips comprising a first electrode, a second electrode, and a light-emitting body connected between the first electrode and the second electrode, wherein the second electrode is located on a side of the light-emitting body away from the base layer;

[0007] a filling layer, the filling layer comprising at least one filling portion, the filling portion being located at least between two adjacent light-emitting chips, the filling portion having a head end and a tail end arranged along the circumference of the light-emitting body, and a thickness of the filling portion gradually decreasing or stepwise decreasing from the head end to the tail end;

[0008] a first connecting electrode, wherein at least a portion of the first connecting electrode is located within the base layer, an orthographic projection of the first connecting electrode on a reference plane does not overlap or does not completely overlap with an orthographic projection of the light-emitting body on the reference plane, and the reference plane is a plane perpendicular to a thickness direction of the base layer; and

[0009] An auxiliary electrode is electrically connected to the second electrode. At least a portion of the auxiliary electrode is disposed on a surface of the filling portion away from the base layer, and is electrically connected to the first connection electrode through a tail end of the filling portion.

[0010] In some embodiments, the light emitting body includes: a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer, which are sequentially arranged in a direction away from the base layer;

[0011] The sum of the maximum thickness of the filling layer and the thickness of the auxiliary electrode is not less than the thickness of the first semiconductor layer, and the maximum thickness of the filling layer is not greater than the maximum distance from the surface of the second electrode away from the base layer to the base layer.

[0012] In some embodiments, the light-emitting body includes: a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer, which are sequentially arranged in a direction away from the base layer; the first semiconductor layer includes a first bottom surface facing the base layer, a first top surface facing away from the base layer, and a first side surface connected between the first bottom surface and the first top surface;

[0013] The surface of the filling structure facing away from the base layer includes one or more inclined surfaces, and the acute angle formed between the extended surface of each inclined surface and the base layer is smaller than the acute angle formed between the extended surface of the first side surface and the base layer.

[0014] In some embodiments, an acute angle formed between an extended surface of the first side surface of the first semiconductor layer and the base layer is greater than or equal to 70°.

[0015] In some embodiments, the second semiconductor layer includes a second bottom surface facing the base layer, a second top surface facing away from the base layer, and a second side surface connected between the second bottom surface and the second top surface; the multi-quantum well layer includes a third bottom surface facing the base layer, a third top surface facing away from the base layer, and a third side surface connected between the third bottom surface and the third top surface;

[0016] The acute angle between the extended surface of the second side surface and the base layer is smaller than the acute angle between the extended surface of the first side surface and the base layer, and / or the acute angle between the extended surface of the third side surface and the base layer is smaller than the acute angle between the extended surface of the first side surface and the base layer.

[0017] In some embodiments, the acute angle formed between the extended surface of the second side surface and the base layer is less than 70°, and / or the acute angle formed between the extended surface of the third side surface and the base layer is less than 70°.

[0018] In some embodiments, the light-emitting body is surrounded by a filling portion, and the head end and the tail end of the filling portion are close to each other;

[0019] Alternatively, the ends of the plurality of filling portions are close to each other and surround the light-emitting body, wherein the tails of two filling portions are close to each other and are both adjacent to the first connecting electrode.

[0020] In some embodiments, the length of the filling portion is greater than or equal to 1 / 3 of the orthographic projection perimeter of the light-emitting chip on the base layer.

[0021] In some embodiments, the orthographic projection of the light-emitting body on the base layer is a polygon, and at least two adjacent sides of the polygon are adjacent to the same filling portion.

[0022] In some embodiments, the plurality of light-emitting chips are divided into a plurality of light-emitting groups, each of the light-emitting groups includes at least two light-emitting chips; the second electrodes of the light-emitting chips in each light-emitting group are connected to a corresponding first connecting electrode.

[0023] In some embodiments, the plurality of light-emitting chips in the light-emitting group are arranged around the first connecting electrode;

[0024] In the same light-emitting group, the filling portions around the plurality of light-emitting chips form a structure that is centrally symmetrical with respect to the first connecting electrode.

[0025] In some embodiments, the conductivity of the auxiliary electrode is greater than or equal to the conductivity of the second electrode.

[0026] In some embodiments, the auxiliary electrode and the second electrode are both made of the same transparent conductive material.

[0027] In some embodiments, the second electrode is a continuous film layer, or

[0028] The second electrode includes a first portion and a second portion spaced apart from each other. The first portion is electrically connected to the light emitting body. The orthographic projection of the second portion on the base layer surrounds the orthographic projection of the first portion on the base layer. The auxiliary electrode contacts the first portion.

[0029] In some embodiments, the light-emitting substrate further includes: a first insulating layer covering the plurality of light-emitting bodies, and the second electrode is electrically connected to the light-emitting bodies through a via hole penetrating the first insulating layer.

[0030] In some embodiments, the light-emitting body includes: a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer, which are sequentially arranged in a direction away from the base layer, wherein the first semiconductor layer includes: a first bottom surface facing the base layer, a first top surface facing away from the base layer, and a first side surface connected between the first bottom surface and the first top surface;

[0031] The multi-quantum well layer includes a third bottom surface facing the base layer, a third top surface facing away from the base layer, and a third side surface connected between the third bottom surface and the third top surface;

[0032] The first insulating layer covers the entire first side surface and the entire third side surface.

[0033] In some embodiments, the second semiconductor layer includes a second bottom surface facing the base layer, a second top surface facing away from the base layer, and a second side surface connected between the second bottom surface and the second top surface; the first insulating layer covers at least a portion of the second side surface.

[0034] In some embodiments, the first electrode is located on a side of the base layer facing the light-emitting body;

[0035] The light-emitting substrate further includes a plurality of second connecting electrodes, each of the second connecting electrodes corresponding to the light-emitting chips one by one, at least a portion of the second connecting electrodes being located in the base layer and electrically connected to the first electrodes of the corresponding light-emitting chips;

[0036] The orthographic projection of the second connecting electrode on the reference plane overlaps with the orthographic projection of the light-emitting body on the reference plane.

[0037] In some embodiments, the light-emitting chip is a mini-LED light-emitting chip or a Micro-LED light-emitting chip.

[0038] In some embodiments, the light-emitting substrate is a display panel, and the base layer includes a driving component for driving the light-emitting chip to emit light. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0040] FIG1 is a schematic diagram of a light-emitting substrate provided in some embodiments.

[0041] FIG2 is a cross-sectional view taken along line AA' in FIG1.

[0042] FIG3 is another cross-sectional view along line AA′ in FIG1 .

[0043] FIG4 is a plan view of a light-emitting substrate provided in some embodiments of the present disclosure.

[0044] FIG. 5 is a schematic diagram of the filling layer in FIG. 4 .

[0045] FIG. 6 is a partial schematic diagram of the Q region in FIG. 4 .

[0046] FIG. 7 is a schematic diagram of the filling portion in FIG. 6 .

[0047] FIG. 8 is a partial cross-sectional view of the light emitting chip in FIG. 6 viewed from different sides around the periphery.

[0048] FIG. 9 is a cross-sectional view taken along line BB′ in FIG. 6 .

[0049] FIG10 is another cross-sectional view taken along line BB′ in FIG6 .

[0050] FIG11 is a plan view of a light-emitting substrate provided in some other embodiments of the present disclosure.

[0051] FIG12 is a plan view of a light-emitting group and its surrounding auxiliary electrodes in FIG11.

[0052] FIG. 13 is a plan view of a light-emitting chip and auxiliary electrodes surrounding the light-emitting chip in FIG. 11 .

[0053] FIG. 14A is a schematic diagram of the filling layer in FIG. 11 .

[0054] FIG. 14B is a schematic diagram of the filling portion in FIG. 13 .

[0055] FIG. 15 is a partial cross-sectional view of the light emitting chip in FIG. 13 viewed from different sides around the perimeter. DETAILED DESCRIPTION

[0056] The following describes the specific embodiments of the present disclosure in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure.

[0057] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0058] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should have the usual meanings understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0059] As used herein, "parallel" and "perpendicular" include the conditions described and conditions similar to the conditions described, and the range of the similar conditions is within an acceptable deviation range, wherein the acceptable deviation range is determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the specific quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range for approximate parallelism can be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range for approximate perpendicularity can also be, for example, a deviation within 5°.

[0060] It will be understood that when a layer or element is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present therebetween.

[0061] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized exemplary drawings. In the drawings, the thicknesses of layers and regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are contemplated. Therefore, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include deviations in shape due to, for example, manufacturing. For example, an etched region shown as a rectangle will typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to illustrate the actual shape of regions of the device and are not intended to limit the scope of the exemplary embodiments.

[0062] Figure 1 is a schematic diagram of a light-emitting substrate provided in some embodiments, Figure 2 is a cross-sectional view along line A-A' in Figure 1, and Figure 3 is another cross-sectional view along line A-A' in Figure 1. As shown in Figures 1 to 3, the light-emitting substrate includes: a base layer 10; and a plurality of light-emitting chips 20 arranged on the base layer 10, the light-emitting chip 20 includes a first electrode 21, a second electrode 22 and a light-emitting body 23 connected therebetween, and the second electrode 22 is located on the side of the light-emitting body 23 away from the base layer 10.

[0063] In addition, the light-emitting substrate further includes a first connection electrode 30. At least a portion of the first connection electrode 30 is located within the base layer 10. The orthographic projection of the first connection electrode 30 on a reference plane does not overlap or does not completely overlap with the orthographic projection of the light-emitting body 23 on the reference plane. The reference plane is a plane perpendicular to the thickness direction of the base layer 10. The second electrode 22 of the light-emitting chip 20 is electrically connected to the first connection electrode 30.

[0064] As shown in Figure 2 , ideally, the second electrodes 22 of multiple light-emitting chips are connected to form a single second electrode layer 22a, which is electrically connected to the first connection electrode 30. However, when the light-emitting body 23 is thick and the surface area facing the base layer 10 is small (i.e., the side surface of the light-emitting body 23 is steep), the second electrode 22 is prone to fracture, as shown in Figure 3 . Furthermore, even if an auxiliary electrode is provided between two adjacent light-emitting bodies 23 in the second electrode layer 22a, the auxiliary electrode is susceptible to fracture, thereby affecting the light emission of the light-emitting chip.

[0065] Figure 4 is a plan view of a light-emitting substrate provided in some embodiments of the present disclosure, Figure 5 is a schematic diagram of the filling layer in Figure 4, Figure 6 is a partial schematic diagram of the Q region in Figure 4, Figure 7 is a schematic diagram of the filling portion in Figure 6, Figure 8 is a partial cross-sectional view of the light-emitting chip in Figure 6 viewed from different sides, Figure 9 is a cross-sectional view along line BB' in Figure 6, and Figure 10 is another cross-sectional view along line BB' in Figure 6. Figure 11 is a plan view of a light-emitting substrate provided in other embodiments of the present disclosure, Figure 12 is a plan view of a light-emitting group and its surrounding auxiliary electrodes in Figure 11, Figure 13 is a plan view of a light-emitting chip in Figure 11 and its surrounding auxiliary electrodes, Figure 14A is a schematic diagram of the filling layer in Figure 11, Figure 14B is a schematic diagram of the filling portion in Figure 13, and Figure 15 is a partial cross-sectional view of the light-emitting chip in Figure 13 viewed from different sides.

[0066] As shown in FIG. 4 to FIG. 15 , the light emitting substrate includes a base layer 10 , and a plurality of light emitting chips 20 , a filling layer 50 , a first connection electrode 30 , and an auxiliary electrode 40 disposed on the base layer 10 .

[0067] The light emitting chip 20 includes a first electrode 21 , a second electrode 22 and a light emitting body 23 connected therebetween. The second electrode 22 is located on a side of the light emitting body 23 away from the base layer 10 .

[0068] The filling layer 50 includes at least one filling portion 51. The filling portion 51 is located at least between two adjacent light-emitting chips 20. That is, at least a portion of the filling portion 51 is located between the two adjacent light-emitting chips 20. The filling portion 51 has a leading end and a trailing end arranged along the circumference of the light-emitting body 23. The thickness of the filling portion 51 gradually decreases or decreases in a step-like manner from the leading end to the trailing end. In Figures 5, 7, 14A, and 14B, the arrows indicate the changing trend of the filling portion 51. The thickness of the filling portion 51 gradually decreases along the direction of the arrows.

[0069] It should be noted here that the so-called "filling portion 51 has a head end and a tail end arranged along the circumference of the light-emitting body 23" does not mean that the filling portion 51 must completely surround the light-emitting body 23. It is also possible that the filling portion 51 is arranged along the circumference of the light-emitting body 23 for half a circle, 1 / 3 of a circle, or other lengths.

[0070] At least a portion of the first connection electrode 30 is located within the base layer 10. For example, the first connection electrode 30 may be entirely located within the base layer 10; alternatively, the first connection electrode 30 may be partially located within the base layer 10, with the remainder located on the surface of the base layer 10 facing the light-emitting body 23. Furthermore, the orthographic projection of the first connection electrode 30 on a reference plane does not overlap or does not completely overlap with the orthographic projection of the light-emitting body 23 on the reference plane; the reference plane is a plane perpendicular to the thickness direction of the base layer 10.

[0071] The auxiliary electrode 40 is electrically connected to the second electrode 22 . At least a portion of the auxiliary electrode 40 is disposed on a surface of the filling portion 51 away from the base layer 10 , and is electrically connected to the first connection electrode 30 through a tail end of the filling portion 51 .

[0072] In the embodiment of the present disclosure, since the thickness of the filling portion 51 gradually decreases or decreases in a step-like manner from the head end to the tail end, and at least a portion of the auxiliary electrode 40 is located on the surface of the filling portion 51 away from the base layer 10, and is electrically connected to the first connecting electrode 30 through the tail end of the filling portion 51 where the thickness is the smallest, the auxiliary electrode 40 is arranged on a slope with a gentler slope. Even if the side of the light-emitting body 23 is steeper, it will not affect the auxiliary electrode 40, thereby reducing the occurrence of breakage of the auxiliary electrode 40, and thereby improving the connection reliability between the light-emitting body and the first connecting electrode 30.

[0073] In some embodiments, as shown in Figures 9 and 10, the light-emitting body 23 includes: a first semiconductor layer 231, a multi-quantum well layer 233, and a second semiconductor layer 232, arranged in sequence in a direction away from the base layer 10. One of the first semiconductor layer 231 and the second semiconductor layer 232 is an N-type semiconductor layer, and the other is a P-type semiconductor layer. The sum of the maximum thickness of the filling layer 50 and the thickness of the auxiliary electrode 40 is no less than the thickness of the first semiconductor layer 231, and the maximum thickness of the filling layer 50 is no greater than the maximum distance from the surface of the second electrode 22 away from the base layer 10 to the base layer 10.

[0074] When the second electrode 22 breaks, the break typically occurs at a location opposite the first side surface of the first semiconductor layer 231. Therefore, in the disclosed embodiment, the sum of the maximum thickness of the filling layer 50 and the thickness of the auxiliary electrode 40 is set to be no less than the thickness of the first semiconductor layer 231. This ensures that even if the second electrode 22 breaks, the auxiliary electrode 40 remains electrically connected to the portion of the second electrode 22 connected to the light-emitting body, thereby ensuring normal light emission from the light-emitting chip. Furthermore, the maximum thickness of the filling layer 50 is no greater than the maximum distance from the surface of the second electrode 22 away from the base layer 10 to the base layer 10. This prevents the slope of the surface of the filling layer 50 away from the base layer 10 from being too steep, thereby preventing the auxiliary electrode 40 from breaking.

[0075] In some embodiments, the light-emitting body 23 includes: a first semiconductor layer 231, a multi-quantum well layer 233, and a second semiconductor layer 232, arranged in sequence away from the base layer 10. One of the first semiconductor layer 231 and the second semiconductor layer 232 is an N-type semiconductor layer, and the other is a P-type semiconductor layer. The first semiconductor layer 231 includes: a first bottom surface facing the base layer 10, a first top surface facing away from the base layer 10, and a first side surface connected between the first bottom surface and the first top surface.

[0076] In which, the orthographic projection of the first top surface on the base layer 10 is located within the range of the orthographic projection of the first bottom surface on the base layer 10, and the surface of the filling portion 51 facing away from the base layer 10 includes one or more inclined surfaces, and the acute angle between the extended surface of each inclined surface and the base layer 10 is smaller than the acute angle between the extended surface of the first side surface and the base layer 10, so as to prevent the auxiliary electrode 40 from breaking.

[0077] In some embodiments, the acute angle α formed between the extended surface of the first side surface of the first semiconductor layer 231 and the base layer 10 is greater than or equal to 70°. For example, α is 70°, 75°, 78°, 80°, 82°, 84°, 86°, or 88°.

[0078] In some embodiments, the acute angle β formed by the extended surface of each inclined surface in the surface of the filling portion 51 facing away from the base layer 10 and the base layer 10 can be set to a smaller angle to reduce the risk of breakage of the auxiliary electrode 40. In one example, β is less than 70°, for example, β is in the range of [60°, 70°), or in the range of [50°, 60°), or in the range of [40°, 50°), or in the range of [30°, 40°), or in the range of [20°, 30°), or less than 20°.

[0079] In some embodiments, the second semiconductor layer 232 includes a second bottom surface facing the base layer 10, a second top surface facing away from the base layer 10, and a second side surface connected between the second bottom surface and the second top surface. The multi-quantum well layer 233 includes a third bottom surface facing the base layer 10, a third top surface facing away from the base layer 10, and a third side surface connected between the third bottom surface and the third top surface.

[0080] In which, the orthographic projection of the second top surface on the base layer 10 is located within the range of the orthographic projection of the second bottom surface on the base layer 10, and the acute angle formed by the extended surface of the second side surface and the base layer 10 is smaller than the acute angle formed by the extended surface of the first side surface and the base layer 10; and / or, the acute angle formed by the extended surface of the third side surface and the base layer 10 is smaller than the acute angle formed by the extended surface of the first side surface and the base layer 10.

[0081] In some embodiments, the orthographic projection of the first semiconductor layer 231 on the base layer 10 covers the orthographic projection of the multi-quantum well layer 233 on the base layer 10, and the orthographic projection of the multi-quantum well layer 233 on the base layer 10 covers the orthographic projection of the second semiconductor layer 232 on the base layer 10. The orthographic projection of the first side surface on the base layer 10 surrounds the orthographic projection of the third side surface on the base layer 10, and the orthographic projection of the third side surface on the base layer 10 surrounds the orthographic projection of the second side surface on the base layer 10. The orthographic projection of the first side surface on the base layer 10 and the orthographic projection of the third side surface on the base layer 10 may be in contact with or spaced apart from each other; and the orthographic projection of the third side surface on the base layer 10 and the orthographic projection of the second side surface on the base layer 10 may be in contact with or spaced apart from each other.

[0082] In some embodiments, the acute angle formed between the extended surface of the second side surface and the base layer 10 is less than 70°, thereby preventing the second electrode 22 from breaking at a position opposite the second side surface. And / or, the acute angle formed between the extended surface of the third side surface and the base layer 10 is less than 70°, thereby preventing the second electrode 22 from breaking at a position opposite the third side surface.

[0083] In some embodiments, the length of the filling portion 51 is greater than or equal to 1 / 3 of the perimeter of the orthogonal projection of the light-emitting chip 20 on the base layer 10, thereby minimizing the slope angle of the surface of the filling portion 51 and preventing the auxiliary electrode 40 from breaking. For example, the length of the filling portion 51 is [1 / 3, 1 / 2] times, [1 / 3, 2 / 3] times, or [2 / 3, 1] times the perimeter of the orthogonal projection of the light-emitting chip 20 on the base layer 10.

[0084] In some embodiments, the light-emitting chips 20 are arranged in an array, and the distance between two adjacent light-emitting chips 20 in the same row and the distance between two adjacent light-emitting chips 20 in the same column are both between 0.2 and 1.5 μm, for example, 0.2 μm, 0.5 μm, 0.8 μm, 1.0 μm, or 1.2 μm. The distance between two adjacent light-emitting chips 20 refers to the distance between the orthographic projections of the two adjacent light-emitting chips 20 on the substrate 10, as shown in d in FIG9 .

[0085] In some embodiments, as shown in FIG9 , the second electrode 22 includes a first portion 221 and a second portion 222 spaced apart from each other. The first portion 221 is electrically connected to the light-emitting body 23. The orthographic projection of the second portion 222 on the base layer 10 surrounds the orthographic projection of the first portion 221 on the base layer 10. The auxiliary electrode 40 is in contact with the first portion 221. The first portion 221 and the second portion 222 are formed using the same patterning process. The first portion 221 and the second portion 222 can be a two-part structure formed after a continuous film layer is broken. In the embodiment of the present disclosure, even if the second electrode 22 is broken to form the first portion 221 and the second portion 222, the electrical connection between the light-emitting body 23 and the first connection electrode 30 can be ensured by the provision of the filling portion 51 and the auxiliary electrode 40.

[0086] In some embodiments, at least a portion of the first portion 221 is opposite to the second side of the second semiconductor layer 232 , and the second portion 222 is opposite to the first side of the first semiconductor layer 231 .

[0087] Of course, as shown in FIG. 10 , the second electrode 22 may also be a continuous film layer, and the second electrodes 22 of a plurality of light-emitting chips 20 are connected to form a whole second electrode layer 22 a.

[0088] In some embodiments, as shown in Figures 8 to 10, the light-emitting substrate further includes a first insulating layer 60, which covers the plurality of light-emitting bodies 23. The second electrode 22 is electrically connected to the light-emitting body 23 via a via hole penetrating the first insulating layer 60. The first insulating layer 60 can be made of materials such as silicon nitride, silicon oxide, and silicon oxynitride, and can have a single-layer structure or a multi-layer structure.

[0089] In some embodiments, the first semiconductor layer 231 includes a first bottom surface facing the base layer 10, a first top surface facing away from the base layer 10, and a first side surface connected between the first bottom surface and the first top surface. The multi-quantum well layer 233 includes a third bottom surface facing the base layer 10, a third top surface facing away from the base layer 10, and a third side surface connected between the third bottom surface and the third top surface. The first insulating layer 60 covers the entire first side surface and the entire third side surface to prevent a short circuit between the first semiconductor layer 231, the multi-quantum well layer 233, and the second electrode 22.

[0090] In some embodiments, the second semiconductor layer 232 includes a second bottom surface facing the base layer 10, a second top surface facing away from the base layer 10, and a second side surface connected between the second bottom surface and the second top surface. The first insulating layer 60 may also cover the entire second side surface, with a via in the first insulating layer 60 exposing at least a portion of the second top surface.

[0091] In some embodiments, as shown in Figures 7 and 8, the light-emitting body 23 is surrounded by a filling portion 51, with the leading and trailing ends of the filling portion 51 close to each other. The thickness of the filling portion 51 gradually decreases from position a to position b, from position b to position c, from position c to position d, and from position d to position d'.

[0092] In other embodiments, multiple filling portions 51 are close to each other and surround the light-emitting body 23. It should be noted that "close to each other" means that the head end of each filling portion 51 is close to the head end or tail end of one of the other filling portions 51. For example, as shown in Figures 14A to 15, the filling layer 50 includes two filling portions 51, the head ends of the two filling portions 51 are connected to each other, and the tail ends are close to each other (wherein, in Figures 14A to 15, the head ends of the two filling portions 51 are connected to position g, and the tail ends are close to position e); for another example, the filling layer 50 includes four filling portions 51, the tail end of the first filling portion 51 is close to the head end of the second filling portion 51, the tail end of the second filling portion 51 is close to the head end of the third filling portion 51, the tail end of the third filling portion 51 is close to the head end of the fourth filling portion 51, and the tail end of the fourth filling portion 51 is close to the head end of the first filling portion 51. For another example, the filling layer 50 includes four filling portions 51, the tail end of the first filling portion 51 is close to the tail end of the second filling portion 51, the head end of the second filling portion 51 is close to the head end of the third filling portion 51, the tail end of the third filling portion 51 is close to the tail end of the fourth filling portion 51, and the head end of the fourth filling portion 51 is close to the head end of the first filling portion 51. Of course, the filling layer 50 may also include other numbers of filling portions 51, which will not be listed here one by one.

[0093] In some embodiments, when the filling layer 50 includes a plurality of filling portions 51 , tails of two filling portions 51 are close to each other and adjacent to the first connection electrode 30 , thereby preventing the auxiliary electrode 40 from being broken between two adjacent filling portions 51 .

[0094] In some embodiments, as shown in Figures 4, 6, 11 to 13, the orthographic projection of the light-emitting body 23 on the base layer 10 is a polygon, and at least two adjacent sides of the polygon are adjacent to the same filling portion 51. In this case, the filling portion 51 can be made of a sufficient length, which is conducive to making the surface of the filling portion 51 facing away from the base layer 10 smoother. For example, the orthographic projection of the light-emitting body 23 on the base layer 10 is a rectangle, as shown in Figure 13, and two adjacent sides of the rectangle are adjacent to the same filling portion 51; for another example, as shown in Figure 6, the four sides of the rectangle are adjacent to the same filling portion 51. Of course, the orthographic projection of the light-emitting body 23 on the base layer 10 can also be a hexagonal, octagonal or other structure.

[0095] In some embodiments, as shown in FIG4 , a portion of the light-emitting chips 20 are surrounded by one or more filling portions 51, while another portion of the light-emitting chips 20 (e.g., the light-emitting chips 20 near the edge of the display substrate) are not surrounded by the filling portion 51 and are adjacent to the filling portion 51 on only one or both sides. In other embodiments, as shown in FIG11 , each light-emitting chip 20 is surrounded by one or more filling portions 51.

[0096] In some embodiments, as shown in Figures 11 to 13, the light-emitting chips 20 are divided into light-emitting groups, each light-emitting group including at least two light-emitting chips 20. The second electrodes 22 of the light-emitting chips 20 in each light-emitting group are connected to a corresponding first connection electrode 30, thereby reducing the number of first connection electrodes 30 and simplifying the overall structure.

[0097] In some embodiments, multiple light-emitting chips 20 in a light-emitting group are arranged around a first connection electrode 30. Within a light-emitting group, the filling portions 51 surrounding the multiple light-emitting chips 20 form a centrally symmetrical structure about the first connection electrode 30. For example, as shown in FIG12 , each light-emitting group includes 2×2 light-emitting chips 20. Each of the 2×2 light-emitting chips 20 is surrounded by a filling portion 51, and the filling portions 51 surrounding the four light-emitting chips 20 form a centrally symmetrical structure about the first connection electrode 30. Of course, a light-emitting group may also include other numbers of light-emitting chips 20, for example, 6 or 8 light-emitting chips 20.

[0098] In some embodiments, the conductivity of the auxiliary electrode 40 is greater than or equal to the conductivity of the second electrode 22 , thereby reducing the resistance of the overall structure formed by the auxiliary electrode 40 and the second electrode 22 .

[0099] In one example, the material of the second electrode 22 includes transparent conductive materials such as indium tin oxide (ITO), and the auxiliary electrode 40 can be made of a metal material, for example, gold (Au), an alloy of gold, silver (Ag), an alloy of silver, aluminum (Al), an alloy of aluminum, aluminum nitride (AlNx), tungsten (W), tungsten nitride (WNx), copper (Cu), an alloy of copper, nickel (Ni), chromium (Cr), chromium nitride (CrNx), molybdenum (Mo), an alloy of molybdenum, titanium (Ti), titanium nitride (TiNx), platinum (Pt). The second electrode 22 can be a single-layer or multi-layer structure. In one example, the auxiliary electrode 40 can be a stack of Au / Cr / Pt.

[0100] In other embodiments, the materials of both the auxiliary electrode 40 and the second electrode 22 are transparent conductive materials and are the same. In this case, the auxiliary electrode 40 and the second electrode 22 can be fabricated synchronously using the same patterning process, thereby simplifying the process. For example, both the auxiliary electrode 40 and the second electrode 22 are made of ITO.

[0101] In some embodiments, the material of the filling portion 51 can include inorganic insulating materials such as silicon oxide, silicon nitride, silicon oxynitride, etc.; of course, organic insulating materials such as resin can also be used.

[0102] In some embodiments, the above N-type semiconductor layer can contain N-type GaN, and the P-type semiconductor layer can contain In x Al y Ga 1-x-y N (0≤x<1, 0≤y<1, 0≤x + y<1) component P-type nitride semiconductor layer, and the P-type impurity can be magnesium. For example, the P-type semiconductor layer can be a single-layer structure, but in some exemplary embodiments, it can have a multi-layer structure containing different components. In the multiple quantum well layer 233, the quantum well layer 233 and the quantum barrier layer are stacked alternately with each other. For example, the quantum well layer 233 and the quantum barrier layer can respectively include In x Al y Ga 1-x-y N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) of different components. In a certain example, the quantum well layer 233 can include In x Ga 1-x N (0<x≤1) component, and the quantum barrier layer can include GaN or AlGaN.

[0103] It should be noted that in other examples, the multiple quantum well layer 233 can be replaced by a single quantum well layer 233.

[0104] The material of the first electrode 21 may include at least one of aluminum (Al), gold (Au), chromium (Cr), nickel (Ni), titanium (Ti), ruthenium (Ru), silver (Ag), zinc (Zn), and platinum (Pt).

[0105] In some embodiments, the first electrode 21, the light-emitting body 23, and the second electrode 22 are sequentially arranged in a direction away from the base layer 10. The light-emitting substrate further includes a plurality of second connecting electrodes 31, and the second connecting electrodes 31 are arranged in a one-to-one correspondence with the light-emitting chips 20. At least part of the second connecting electrode 31 is located in the base layer 10. For example, the second connecting electrode 31 may be entirely located in the base layer 10; or, part of the second connecting electrode 31 is located in the base layer 10, and the remaining part is located on the surface of the base layer 10 facing the light-emitting body 23 and / or on the surface of the base layer 10 facing away from the light-emitting body 23. In addition, the orthographic projection of the second connecting electrode 31 on the reference plane overlaps with the orthographic projection of the light-emitting body 23 on the reference plane. For example, the orthographic projection of the second connecting electrode 31 on the reference plane is within the range of the orthographic projection of the light-emitting body 23 on the reference plane.

[0106] In some embodiments, the light emitting chip 20 is a mini-LED light emitting chip or a micro-LED light emitting chip. The light emitting substrate can be used in a backlight module to provide backlight for a liquid crystal display panel; of course, the light emitting substrate can also be a display panel that can emit light on its own.

[0107] In some embodiments, the light-emitting substrate is a display panel, and the base layer 10 includes a driving component for driving the light-emitting chip 20 to emit light. For example, the base layer 10 may be a driving backplane, and the first connection electrode 30 and the second connection electrode 31 may be driving electrodes.

[0108] In one example, the driving backplane is a silicon substrate provided with a driving circuit, and the driving circuit can be embedded in the silicon substrate. During the preparation of the light-emitting substrate, the driving backplane can be first fabricated and provided, and multiple first electrodes 21 and a light-emitting main body layer can be fabricated on a sapphire layer or other material layer; thereafter, the sapphire layer provided with the first electrodes 21 and the light-emitting main body layer is transferred to the driving backplane, and the multiple first electrodes 21 are electrically connected to the second connection electrode 31 in the driving backplane; then, the sapphire layer is removed and the light-emitting main body layer is patterned to form multiple light-emitting bodies 23; and then, a second electrode layer, a filling layer 50, and an auxiliary electrode 40 are sequentially formed.

[0109] In another example, the driving backplane may include a base substrate and a driving circuit disposed on the base substrate. The base substrate may be a glass substrate or a flexible substrate made of a material such as polyimide (PI). During the preparation of the light-emitting substrate, the driving circuit and a second insulating layer covering the driving circuit may be first formed on the base substrate. The second insulating layer may be an inorganic film layer such as silicon nitride, silicon oxide, or silicon oxynitride, or an organic film layer. The first connecting electrode 20 and the second connecting electrode 31 penetrate the second insulating layer and are electrically connected to the driving circuit. In addition, a light-emitting main layer and a plurality of first electrodes 21 are produced on a sapphire layer or other material layer, and the plurality of first electrodes 21 are located on the side of the light-emitting main layer away from the sapphire layer; thereafter, the sapphire layer provided with the first electrodes 21 and the light-emitting main layer is transferred to the driving backplane (at this time, the sapphire layer and the driving backplane are arranged opposite to each other, and the first electrode 21 and the light-emitting main layer are located between the sapphire layer and the driving backplane), and the plurality of first electrodes 21 are electrically connected to the second connecting electrode 31 in the driving backplane; then, the sapphire layer is removed and the light-emitting main layer is patterned to form a plurality of light-emitting main bodies 23; and then the second electrode layer, the filling layer 50 and the auxiliary electrode 40 are formed in sequence.

[0110] It is understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present disclosure, and the present disclosure is not limited thereto. Those skilled in the art may make various modifications and improvements without departing from the spirit and substance of the present disclosure, and such modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A light-emitting substrate, characterized in that: include: Grassroots; A plurality of light-emitting chips are arranged on the base layer, wherein the light-emitting chips include a first electrode, a second electrode, and a light-emitting body connected between the first electrode and the second electrode, and the second electrode is located at a side of the light-emitting body away from the base layer; A filling layer, the filling layer comprising at least one filling portion, the filling portion being located at least between two adjacent light-emitting chips, the filling portion having a head end and a tail end arranged along the circumference of the light-emitting body, and a thickness of the filling portion gradually decreasing or stepwise decreasing from the head end to the tail end; a first connecting electrode, wherein at least a portion of the first connecting electrode is located in the base layer, an orthographic projection of the first connecting electrode on a reference plane does not overlap or does not completely overlap with an orthographic projection of the light-emitting body on the reference plane, and the reference plane is a plane perpendicular to a thickness direction of the base layer; and An auxiliary electrode is electrically connected to the second electrode, wherein at least a portion of the auxiliary electrode is disposed on a surface of the filling portion away from the base layer, and is electrically connected to the first connection electrode through a tail end of the filling portion.

2. The light-emitting substrate according to claim 1, characterized in that: The light-emitting body comprises: a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer, which are arranged in sequence in a direction away from the base layer; The sum of the maximum thickness of the filling layer and the thickness of the auxiliary electrode is not less than the thickness of the first semiconductor layer, and the maximum thickness of the filling layer is not greater than the maximum distance from the surface of the second electrode away from the base layer to the base layer.

3. The light-emitting substrate according to claim 1, characterized in that: The light-emitting body comprises: a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer, which are sequentially arranged in a direction away from the base layer; the first semiconductor layer comprises a first bottom surface facing the base layer, a first top surface facing away from the base layer, and a first side surface connected between the first bottom surface and the first top surface; The surface of the filling structure facing away from the base layer includes one or more inclined surfaces, and the acute angle formed between the extended surface of each inclined surface and the base layer is smaller than the acute angle formed between the extended surface of the first side surface and the base layer.

4. The light-emitting substrate according to claim 3, characterized in that: An acute angle formed between an extended surface of the first side surface of the first semiconductor layer and the base layer is greater than or equal to 70°.

5. The light-emitting substrate according to claim 3, characterized in that: The second semiconductor layer includes a second bottom surface facing the base layer, a second top surface facing away from the base layer, and a second side surface connected between the second bottom surface and the second top surface; the multi-quantum well layer includes a third bottom surface facing the base layer, a third top surface facing away from the base layer, and a third side surface connected between the third bottom surface and the third top surface; The acute angle between the extended surface of the second side surface and the base layer is smaller than the acute angle between the extended surface of the first side surface and the base layer, and / or the acute angle between the extended surface of the third side surface and the base layer is smaller than the acute angle between the extended surface of the first side surface and the base layer.

6. The light-emitting substrate according to claim 5, characterized in that: The acute angle formed by the extended surface of the second side surface and the base layer is less than 70°, and / or the acute angle formed by the extended surface of the third side surface and the base layer is less than 70°.

7. The light-emitting substrate according to any one of claims 1 to 6, characterized in that: The light-emitting body is surrounded by a filling portion, and the head end and the tail end of the filling portion are close to each other; Alternatively, the ends of the multiple filling parts are close to each other and surround the light-emitting body together, wherein the tails of two of the filling parts are close to each other and are both adjacent to the first connecting electrode.

8. The light-emitting substrate according to any one of claims 1 to 6, characterized in that: The length of the filling portion is greater than or equal to 1 / 3 of the perimeter of the orthographic projection of the light emitting chip on the substrate.

9. The light-emitting substrate according to any one of claims 1 to 6, characterized in that: The orthographic projection of the light-emitting body on the base layer is a polygon, and at least two adjacent sides of the polygon are adjacent to the same filling portion.

10. The light emitting substrate according to any one of claims 1 to 6, characterized in that: The plurality of light-emitting chips are divided into a plurality of light-emitting groups, each of which includes at least two light-emitting chips; the second electrodes of the light-emitting chips in each of the light-emitting groups are connected to a corresponding first connecting electrode.

11. The light emitting substrate according to claim 10, characterized in that: The plurality of light-emitting chips in the light-emitting group are arranged around the first connecting electrode; In the same light-emitting group, the filling parts around the plurality of light-emitting chips form a structure that is centrally symmetrical about the first connecting electrode.

12. The light-emitting substrate according to any one of claims 1 to 6, characterized in that: The conductivity of the auxiliary electrode is greater than or equal to the conductivity of the second electrode.

13. The light emitting substrate according to claim 12, characterized in that: The auxiliary electrode and the second electrode are both made of transparent conductive materials, and the materials are the same.

14. The light-emitting substrate according to any one of claims 1 to 6, characterized in that: The second electrode is a continuous film layer, or The second electrode includes a first portion and a second portion spaced apart from each other, the first portion is electrically connected to the light emitting body, an orthographic projection of the second portion on the substrate surrounds an orthographic projection of the first portion on the substrate, and the auxiliary electrode contacts the first portion.

15. The light emitting substrate according to any one of claims 1 to 6, characterized in that: The light emitting substrate further includes: a first insulating layer covering the plurality of light emitting bodies, and the second electrode is electrically connected to the light emitting bodies through a via hole penetrating the first insulating layer.

16. The light emitting substrate according to claim 15, characterized in that: The light-emitting body comprises: a first semiconductor layer, a multi-quantum well layer, and a second semiconductor layer, which are sequentially arranged in a direction away from the base layer, wherein the first semiconductor layer comprises: a first bottom surface facing the base layer, a first top surface facing away from the base layer, and a first side surface connected between the first bottom surface and the first top surface; The multi-quantum well layer comprises a third bottom surface facing the base layer, a third top surface facing away from the base layer, and a third side surface connected between the third bottom surface and the third top surface; The first insulating layer covers the entire first side surface and the entire third side surface.

17. The light emitting substrate according to claim 16, characterized in that: The second semiconductor layer includes a second bottom surface facing the base layer, a second top surface facing away from the base layer, and a second side surface connected between the second bottom surface and the second top surface; the first insulating layer covers at least a portion of the second side surface.

18. The light emitting substrate according to any one of claims 1 to 6, characterized in that: The first electrode is located on a side of the base layer facing the light-emitting body; The light-emitting substrate further comprises a plurality of second connecting electrodes, each of the second connecting electrodes corresponds to the light-emitting chip one by one, at least a portion of the second connecting electrodes is located in the base layer and is electrically connected to the first electrode of the corresponding light-emitting chip; The orthographic projection of the second connecting electrode on the reference plane overlaps with the orthographic projection of the light-emitting body on the reference plane.

19. The light-emitting substrate according to any one of claims 1 to 6, characterized in that: The light-emitting chip is a mini-LED light-emitting chip or a Micro-LED light-emitting chip.

20. The light-emitting substrate according to any one of claims 1 to 6, characterized in that: The light-emitting substrate is a display panel, and the base layer includes a driving component for driving the light-emitting chip to emit light.

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