Display substrate and manufacturing method therefor

Abstract

A display substrate and a manufacturing method therefor. The display substrate comprises: a base substrate; a plurality of first electrodes, which are located on the base substrate, wherein there is a gap between adjacent first electrodes; a plurality of light-emitting layers, which are located on the side of the plurality of first electrodes away from the base substrate and correspond to the plurality of first electrodes on a one-to-one basis, wherein the projections of the first electrodes on the base substrate are located within the projections of the corresponding light-emitting layers on the base substrate, adjacent light-emitting layers have different colors and overlap in the gap between the corresponding adjacent first electrodes, the adjacent light-emitting layers respectively have a first slope angle and a second slope angle at an overlapping position, the first slope angle and the second slope angle are non-zero and are different from each other, and the overlapping position is a position at which the surfaces on the side of the adjacent light-emitting layers away from the base substrate intersect each other; and a second electrode, which covers the plurality of light-emitting layers, wherein the second electrode is recessed at the overlapping position.

Description

Display substrate and its manufacturing method Technical Field

[0001] This disclosure relates to the field of display technology, and more specifically to a display substrate and its manufacturing method. Background Technology

[0002] With the development of display technology, the requirements for display devices are becoming increasingly stringent. The display effect of a display device is largely related to the structure of the display substrate, but currently most display substrates cannot meet users' growing demands for display quality. Summary of the Invention

[0003] According to one aspect of this disclosure, a display substrate is provided, comprising: a substrate; a plurality of first electrodes located on the substrate, the plurality of first electrodes having gaps between adjacent first electrodes; a plurality of light-emitting layers located on the side of the plurality of first electrodes away from the substrate and corresponding one-to-one with the plurality of first electrodes, wherein the projection of the first electrode on the substrate lies within the projection of the corresponding light-emitting layer on the substrate, wherein adjacent light-emitting layers have different colors and overlap in the gaps between corresponding adjacent first electrodes, the adjacent light-emitting layers having a first slope angle and a second slope angle at the overlap position, the first slope angle and the second slope angle being non-zero and different from each other, wherein the overlap position is the position where the surfaces of the adjacent light-emitting layers on the side away from the substrate intersect; and a second electrode covering the plurality of light-emitting layers, the second electrode having a recess at the overlap position.

[0004] In some embodiments, the display substrate further includes a pixel defining layer having openings corresponding one-to-one with the plurality of first electrodes, the edge regions of each first electrode being covered by the pixel defining layer and the central regions being exposed through the corresponding openings, and the plurality of light-emitting layers being located on the side of the pixel defining layer away from the substrate.

[0005] In some embodiments, the light-emitting layer includes a flat portion located above an opening in the pixel defining layer and a curved portion surrounding the flat portion, wherein in a cross-section perpendicular to the substrate, the width of the curved portion in a direction parallel to the substrate is greater than the width of the flat portion in the direction parallel to the substrate.

[0006] In some embodiments, one of the adjacent light-emitting layers has a first slope angle at the overlapping position, and the other light-emitting layer has a second slope angle at the overlapping position, wherein the thickness difference between the adjacent light-emitting layers is less than or equal to a preset value, the edge of the one light-emitting layer is covered by the other light-emitting layer, and the first slope angle is greater than the second slope angle.

[0007] In some embodiments, one of the adjacent light-emitting layers has a first slope angle at the overlapping position, and the other light-emitting layer has a second slope angle at the overlapping position; wherein the thickness difference between the adjacent light-emitting layers is greater than a preset value, the thickness of one light-emitting layer is greater than the thickness of the other light-emitting layer, and the first slope angle is greater than the second slope angle.

[0008] In some embodiments, at the bottom of the recess of the second electrode, the second electrode has a third slope angle on the side facing the one light-emitting layer and a fourth slope angle on the side facing the other light-emitting layer. The third slope angle is smaller than the first slope angle, the fourth slope angle is smaller than the second slope angle, and the difference between the third slope angle and the fourth slope angle is smaller than the difference between the first slope angle and the second slope angle.

[0009] In some embodiments, the preset value is in the range of 0.05 μm to 0.15 μm.

[0010] In some embodiments, there is a first height difference between the lowest point of the surface of the second electrode away from the substrate and the top of the second electrode, and a second height difference between the lowest point of the surface of the second electrode near the substrate and the top of the second electrode, wherein the top of the second electrode is the highest point of the surface of the second electrode away from the substrate, and the ratio of the first height difference to the second height difference is in the range of 0.05 to 0.5.

[0011] In some embodiments, there is a first height difference between the lowest point of the surface of the second electrode on the side away from the substrate and the top of the second electrode, and there is a third height difference between the overlapping position of the adjacent light-emitting layers and the surface of the first electrode on the side away from the substrate, wherein the third height difference is greater than the first height difference.

[0012] In some embodiments, the overlapping position does not overlap with the centerline of the gap, wherein the centerline of the gap is equidistant from the first electrodes on both sides of the gap.

[0013] In some embodiments, the bottom of the recess of the second electrode is closer to the centerline of the gap than the overlapping position.

[0014] In some embodiments, the display substrate further includes: a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer, wherein the hole injection layer and the hole transport layer are located between the plurality of light-emitting layers and the plurality of first electrodes, and the hole transport layer is located on the side of the hole injection layer away from the substrate; the electron transport layer and the electron injection layer are located between the plurality of light-emitting layers and the second electrode, and the electron injection layer is located on the side of the electron transport layer away from the substrate.

[0015] In some embodiments, at least one of the hole injection layer, hole transport layer, electron transport layer and electron injection layer is a continuous layer.

[0016] In some embodiments, at least one of the hole injection layer, hole transport layer, electron transport layer and electron injection layer includes a plurality of discrete units, and the plurality of discrete units correspond one-to-one with the plurality of light-emitting layers.

[0017] In some embodiments, the display substrate further includes a spacer located in the gap between adjacent first electrodes and covered by a pixel defining layer.

[0018] In some embodiments, the surface height of the isolator on the side away from the substrate is lower than or equal to the surface height of the first electrode on the side away from the substrate.

[0019] In some embodiments, the first slope angle and the second slope angle are in the range of 15° to 90°.

[0020] In some embodiments, the width of the gap is in the range of 0.2 μm to 1.3 μm.

[0021] In some embodiments, the thickness of the light-emitting layer is... arrive Between them, the thickness difference between different color emitting layers is less than

[0022] In some embodiments, the thickness of the second electrode is... arrive Within the range.

[0023] In some embodiments, the plurality of light-emitting layers include a first color light-emitting layer, a second color light-emitting layer, and a third color light-emitting layer, wherein the first color light-emitting layer, the second color light-emitting layer, and the third color light-emitting layer are formed by a silicon-based independent vapor deposition process, the second color light-emitting layer is formed after the first color light-emitting layer, and the third color light-emitting layer is formed after the second color light-emitting layer.

[0024] In some embodiments, the display substrate further includes an encapsulation layer that covers the second electrode.

[0025] In some embodiments, the display substrate further includes: a planarization layer covering the encapsulation layer; and a plurality of microlenses located on the side of the planarization layer away from the substrate and corresponding one-to-one with the plurality of light-emitting layers.

[0026] According to another aspect of this disclosure, a method for manufacturing a display substrate is also provided, comprising: forming a plurality of first electrodes on the substrate, with gaps between adjacent first electrodes; forming a plurality of light-emitting layers corresponding one-to-one with the plurality of first electrodes on the side of the plurality of first electrodes away from the substrate, wherein the projection of each first electrode on the substrate lies within the projection of the corresponding light-emitting layer on the substrate, wherein adjacent light-emitting layers have different colors and overlap in the gaps between corresponding adjacent first electrodes, the adjacent light-emitting layers having a first slope angle and a second slope angle at the overlap position, the first slope angle and the second slope angle being non-zero and different from each other, wherein the overlap position is the position where the surfaces of the adjacent light-emitting layers on the side away from the substrate intersect; and forming a second electrode covering the plurality of light-emitting layers, the second electrode having a recess at the overlap position.

[0027] In some embodiments, forming a plurality of light-emitting layers corresponding one-to-one with the plurality of first electrodes includes: sequentially forming a first-color light-emitting layer, a second-color light-emitting layer, and a third-color light-emitting layer on the plurality of first electrodes using a silicon-based independent vapor deposition (SBS) process, such that in the gap between adjacent first electrodes, the second-color light-emitting layer covers the first-color light-emitting layer, and the third-color light-emitting layer covers the second-color light-emitting layer.

[0028] In some embodiments, the method further includes: before forming the plurality of light-emitting layers, forming a pixel defining layer having an opening corresponding to each of the plurality of first electrodes, wherein the edge regions of each first electrode are covered by the pixel defining layer and the central regions are exposed through the corresponding openings.

[0029] In some embodiments, the method further includes filling the gap between adjacent first electrodes with a spacer before forming the pixel defining layer. Attached Figure Description

[0030] Figure 1 shows a schematic diagram of the structure of a stacked OLED device.

[0031] Figure 2 shows a schematic cross-sectional view of a display substrate according to an embodiment of the present disclosure.

[0032] Figure 3 shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0033] Figure 4 shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0034] Figure 5A shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0035] Figure 5B shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0036] Figure 6 shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0037] Figure 7 shows a schematic diagram of the structure of a display substrate according to an embodiment of the present disclosure.

[0038] Figures 8A to 8F illustrate the manufacturing process of a display substrate according to an embodiment of the present disclosure. Detailed Implementation

[0039] While this disclosure will be fully described with reference to the accompanying drawings containing preferred embodiments, it should be understood before this description that those skilled in the art can modify the disclosure described herein to obtain the technical effects of this disclosure. Therefore, it should be understood that the above description is a broad disclosure to those skilled in the art and is not intended to limit the exemplary embodiments described herein.

[0040] Furthermore, in the following detailed description, numerous specific details are set forth for ease of explanation to provide a thorough understanding of the embodiments disclosed herein. However, it will be apparent that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and apparatuses are illustrated to simplify the figures.

[0041] Silicon-based OLED microdisplays typically use white light-emitting devices combined with CF filters to achieve color display. Since white light-emitting devices usually employ a conductive layer with strong lateral transmission capabilities, lateral separation of the OLED film layer is necessary. This separation can be achieved by isolating the anode, thus dividing the OLED film layer into multiple independent units.

[0042] Figure 1 shows a schematic diagram of the structure of a stacked OLED device.

[0043] As shown in Figure 1, a Tandem OLED comprises a stacked red emissive layer (RML), a green emissive layer (GML), and a blue emissive layer (BML). A charge generation layer (CGL) connects the upper and lower emissive layers, namely the red / green emissive layers RML / GML and the blue emissive layer BML. However, the charge generation layer CGL has strong lateral transport capabilities, which can easily cause color crosstalk between pixels. Therefore, a groove (DOW) is created between the anodes AN to separate the OLED film layers into independent pixels. However, separating the OLED film layers can easily alter the morphology of the cathode CA, for example, causing punctures in the cathode CA. As shown in Figure 1, the distance between the cathode puncture point P and the anode AN is significantly smaller than the distance between the center of the anode AN and the upper cathode CA, the former being approximately 0.7 times the latter. In this case, the lateral resistance of the cathode CA is smaller than that in the forward direction, making it easier for current to flow laterally to the cathode CA. Since the blue light-emitting layer (BML) is located above the red / green light-emitting layers (RML / GML), the blue light-emitting layer (BML) is more susceptible to cathode puncture than the red / green light-emitting layers (RML / GML), forming a leakage path. This reduces the blue light emission efficiency, further widens the light emission differences between different color pixels, reduces product uniformity, and lowers the Gamma yield.

[0044] The embodiments of this disclosure provide at least one display substrate, including a substrate; a plurality of first electrodes located on the substrate, with gaps between adjacent first electrodes; a plurality of light-emitting layers located on the side of the plurality of first electrodes away from the substrate and corresponding one-to-one with the plurality of first electrodes, wherein the projection of the first electrode on the substrate lies within the projection of the corresponding light-emitting layer on the substrate, wherein adjacent light-emitting layers are of different colors and overlap in the gaps between corresponding adjacent first electrodes, and adjacent light-emitting layers have a first slope angle and a second slope angle at the overlap position, the first slope angle and the second slope angle are not zero and are different from each other, wherein the overlap position is the position where the surfaces of adjacent light-emitting layers on the side away from the substrate intersect; and a second electrode covering the plurality of light-emitting layers, the second electrode having a recess at the overlap position. This arrangement ensures that the second electrode can be located at a certain horizontal height, reducing the voltage drop caused by second electrode puncture and second electrode morphology distortion, thereby reducing the light emission difference of different color light-emitting layers and improving the uniformity of light emission from the display substrate.

[0045] Figure 2 shows a schematic cross-sectional view of a display substrate according to an embodiment of the present disclosure.

[0046] As shown in FIG. 2, the display substrate 100 includes a substrate 110, a plurality of first electrodes 120, a plurality of light-emitting layers 140A, 140B, and 140C, and a second electrode 150. The plurality of first electrodes 120 are located on the substrate 110. The plurality of light-emitting layers 140A, 140B, and 140C are located on the side of the plurality of first electrodes 120 away from the substrate 110, and correspond one-to-one with the plurality of first electrodes 120. The projections of the plurality of first electrodes 120 onto the substrate 110 are respectively located within the projections of the plurality of light-emitting layers 140A, 140B, and 140C onto the substrate 110. The second electrode 150 covers the plurality of light-emitting layers 140A, 140B, and 140C. In some embodiments, the first electrode can be an anode, and the second electrode can be a cathode. However, the embodiments of this disclosure are not limited thereto; in other embodiments, the first electrode can also be a cathode, and the second electrode can also be an anode.

[0047] As shown in Figure 2, there is a gap between adjacent first electrodes 120. Here, the gap refers to the space between the sidewalls of adjacent first electrodes 120 facing each other. The gap has a width D1, which in some embodiments ranges from 0.2 μm to 1.3 μm. The width D1 refers to the minimum distance between the sidewalls of adjacent first electrodes 120 facing each other, but the embodiments of this disclosure are not limited to this. The gap D1 can also refer to the distance between any two points on the sidewalls of adjacent first electrodes 120 facing each other in a direction parallel to the substrate 110, or the average value of the distances.

[0048] In some embodiments, the display substrate 100 further includes a pixel defining layer 130. The pixel defining layer 130 has openings OP corresponding one-to-one with a plurality of first electrodes 120, the edge regions of each first electrode 120 being covered by the pixel defining layer 130 and the central regions being exposed through the corresponding openings OP. A plurality of light-emitting layers 140A, 140B, and 140C are located on the side of the pixel defining layer 130 away from the substrate 110.

[0049] As shown in Figure 2, the light-emitting layer 140A, 140B, or 140C includes a flat portion above the opening OP of the pixel defining layer 130 and a curved portion surrounding the flat portion. In a cross-section perpendicular to the substrate 110, the width of the curved portion in the direction parallel to the substrate 110 is greater than the width of the flat portion in the direction parallel to the substrate 110. Here, "width" can refer to the average of the various widths of the light-emitting layer in the direction parallel to the substrate 110 in a cross-section perpendicular to the substrate 110, or it can refer to any width value of the light-emitting layer in the direction parallel to the substrate 110 in a cross-section perpendicular to the substrate 110.

[0050] In embodiments of this disclosure, adjacent light-emitting layers 140A, 140B, and 140C have different colors. For example, light-emitting layers 140A, 140B, and 140C are respectively a first-color light-emitting layer, a second-color light-emitting layer, and a third-color light-emitting layer. In some embodiments, the first color, the second color, and the third color can be red, green, and blue, respectively. However, embodiments of this disclosure are not limited to this, and the first color, the second color, and the third color can be any three colors. In other embodiments, the multiple light-emitting layers may include light-emitting layers of other colors besides red, green, and blue. The multiple light-emitting layers 140A, 140B, and 140C can all be made of organic light-emitting materials. When the light-emitting layer is a red light-emitting layer, the organic light-emitting material used to make the red light-emitting layer is an organic red light-emitting material; when the light-emitting layer is a green light-emitting layer, the organic light-emitting material used to make the green light-emitting layer is an organic green light-emitting material; and when the light-emitting layer is a blue light-emitting layer, the organic light-emitting material used to make the blue light-emitting layer is an organic blue light-emitting material. In some embodiments, the thickness of the light-emitting layer 140A, 140B, or 140C can be [missing information]. arrive Between them, the thickness difference between different color emitting layers can be less than

[0051] Referring again to Figure 2, multiple light-emitting layers 140A, 140B, and 140C overlap in the gaps between corresponding adjacent first electrodes. For example, the first-color light-emitting layer 140A, the second-color light-emitting layer 140B, and the third-color light-emitting layer 140C can be formed sequentially using a silicon-based side-by-side (SBS) deposition process, wherein the second-color light-emitting layer 140B is formed after the first-color light-emitting layer 140A, and the third-color light-emitting layer 140C is formed after the second-color light-emitting layer 140B. In this way, among adjacent light-emitting layers of different colors, the edge of the first deposited light-emitting layer is covered by the later deposited light-emitting layer. As shown in Figure 2, in the gaps between the first electrodes 120, the edge of the light-emitting layer 140A is covered by the adjacent light-emitting layer 140B, and the edge of the light-emitting layer 140B is covered by the adjacent light-emitting layer 140C. The surface of the light-emitting layer 140A away from the substrate 110 intersects with the surface of the adjacent light-emitting layer 140B away from the substrate 110 at an overlap position P1. The surface of the light-emitting layer 140B away from the substrate 110 intersects with the surface of the adjacent light-emitting layer 140C away from the substrate 110 at an overlap position P2. At the overlap position P1, the light-emitting layer 140A has a slope angle θ1 (first slope angle), and the light-emitting layer 140B has a slope angle θ2 (second slope angle). At the overlap position P2, the light-emitting layer 140B has a slope angle θ3 (first slope angle), and the light-emitting layer 140C has a slope angle θ4 (second slope angle). Here, the slope angle refers to the angle between the direction parallel to the substrate 110 and the tangent of the surface of the light-emitting layer away from the substrate 110 at the overlap position. In some embodiments, the slope angles θ1 to θ4 are in the range of 15° to 90°. In some embodiments, when the thickness difference between adjacent light-emitting layers 140A, 140B, and 140C is less than or equal to a preset value, the slope angle of the light-emitting layer at the overlapping position is related to the formation order of the light-emitting layers; for example, the slope angle of the first-formed light-emitting layer is greater than that of the later-formed light-emitting layer. In some embodiments, the preset value can be in the range of 0.05 μm to 0.15 μm, for example, 0.1 μm. In the embodiment shown in FIG2, the thicknesses of adjacent light-emitting layers 140A, 140B, and 140C are substantially equal, and the thickness difference between the light-emitting layers is less than the preset value. In this case, at the overlapping position P1, the slope angle θ1 of light-emitting layer 140A is greater than the slope angle θ2 of light-emitting layer 140B; at the overlapping position P2, the slope angle θ3 of light-emitting layer 140B is greater than the slope angle θ4 of light-emitting layer 140C. However, the embodiments of this disclosure are not limited to this; the slope angle of the light-emitting layer when the thickness difference is greater than the preset threshold can be related to other factors, which will be described in detail later.

[0052] In some embodiments, the centerline of the gap between the overlapping positions P1 and P2 of the light-emitting layers 140A, 140B, and 140C and the first electrode 120 does not overlap. As shown in FIG2, the gap between the first electrodes 120 has a centerline C, wherein the centerline C is equidistant from the first electrodes 120 on both sides of the gap. The so-called centerline C here can refer to a virtual straight line perpendicular to the substrate 110 in the cross-sectional view, which is located in the gap between the first electrodes 120 and is equidistant from the first electrodes 120 on both sides of the gap. The equidistant distance between the centerline C and the two first electrodes 120 on both sides can mean that the centerline C is equidistant from the sidewalls of the two first electrodes 120 facing each other in a direction parallel to the substrate 110. Taking the overlapping position P2 as an example, the overlapping position P2 is located in the gap between the first electrodes 120 corresponding to adjacent light-emitting layers 140B and 140C, and the overlapping position P2 is located on one side of the centerline C and does not overlap with the centerline C. Similarly, the overlapping position P1 of the light-emitting layers 140A and 140B does not overlap with the center line of the gap where they are located, which will not be elaborated here.

[0053] Referring again to FIG2, the second electrode 150 has recesses at the overlapping positions P1 and P2 of the light-emitting layers 140A, 140B, and 140C. The projection of the recesses onto the substrate 110 lies within the projection of the gap between adjacent first electrodes 120 onto the substrate 110. In some embodiments, the second electrode 150 may be a continuous layer. Here, the recess refers to a pit on the surface of the second electrode 150 away from the substrate 110. FIG2 marks the bottoms Q1 and Q2 of each recess, where the bottom of the recess above the overlapping position P1 is represented by Q1, and the bottom of the recess above the overlapping position P2 is represented by Q2.

[0054] In some embodiments, the bottom of the recess of the second electrode 150 is closer to the center line C of the gap between the first electrodes than the corresponding overlapping position. For example, in FIG2, for light-emitting layers 140B and 140C, the bottom Q2 of the second electrode recess is closer to the center line C of the gap than the overlapping position P2 of the light-emitting layers. Similarly, for light-emitting layers 140A and 140B, the bottom Q1 of the second electrode recess is closer to the center line of the gap than the overlapping position P1 of the light-emitting layers.

[0055] In some embodiments, the thickness of the second electrode 150 is... arrive Within the range. The thickness of the second electrode can be defined as needed. For example, the thickness of the second electrode can refer to the average thickness of each part of the second electrode 150 in the direction perpendicular to the substrate 110, or it can refer to the thickness at any position of the second electrode, or it can refer to the maximum or minimum thickness of the second electrode. There are no restrictions here.

[0056] In some embodiments, the second electrode 150 has a first thickness d1 at the recess and a second thickness d2 at a location corresponding to the center of the first electrode 120. The first thickness d1 may differ from the second thickness d2; for example, d1 may be less than d2. In some embodiments, the ratio of the first thickness d1 to the second thickness d2 is in the range of 80% to 90%. The first thickness d1 and the second thickness d2 can be defined as needed. For example, the first thickness d1 may refer to the thickness of the second electrode 150 at the bottom of the recess, or it may refer to the minimum or average thickness of the second electrode 150 in the recessed region, or it may refer to the average thickness of the second electrode 150 at the bottom of each recess. In other embodiments, the first thickness d1 may also refer to the thickness of the second electrode 150 at the lowest point on the surface of the second electrode 150 near the substrate 110, such as the thickness at the overlapping positions P1, P2, which is not limited in this disclosure. The second thickness d2 here refers to the thickness of the second electrode 150 directly above the center of the first electrode 120, where the center of the first electrode 120 refers to the geometric center of the first electrode 120 in the direction perpendicular to the substrate 110.

[0057] Referring again to Figure 2, in some embodiments, the height difference between the overlapping positions P1 and P2 of the light-emitting layers and the highest point of the light-emitting layer is h3, and the height difference between the highest and lowest points of the light-emitting layer is h4. In some embodiments, the ratio of h3 to h4 is in the range of 0.2 to 0.7. The height difference between the lowest point (i.e., Q1, Q2) of the surface of the second electrode 150 away from the substrate 110 (the upper surface in the figure) and the top of the second electrode 150 is h1 (first height difference), and the height difference between the lowest point of the surface of the second electrode 150 near the substrate 110 (the lower surface in the figure) and the top of the second electrode 150 is h2 (second height difference). In some embodiments, the ratio of h1 to h2 is in the range of 0.05 to 0.5. There is a third height difference between the overlapping positions P1 and P2 of the light-emitting layers and the surface of the first electrode 120 away from the substrate 110 (the upper surface in the figure). In some embodiments, the third height difference is greater than the first height difference h1. The height difference mentioned above refers to the distance in the direction perpendicular to the substrate 110.

[0058] At position Q1, the second electrode 150 has a slope angle θ5 (third slope angle) on the side near the light-emitting layer 140A and a slope angle θ6 (fourth slope angle) on the side near the light-emitting layer 140B. At position Q2, the second electrode 150 has a slope angle θ7 (third slope angle) on the side near the light-emitting layer 140B and a slope angle θ8 (fourth slope angle) on the side near the light-emitting layer 140C. The slope angles θ5 to θ8 can be in the range of 15° to 90°.

[0059] In some embodiments, the slope angle of the second electrode 150 at the recess is related to the slope angle of the light-emitting layer below the second electrode 150 at the overlap. For example, the slope angle θ1 of the light-emitting layer 140A at the overlap position P1 is greater than the slope angle θ5 of the corresponding second electrode portion; the slope angle θ2 of the light-emitting layer 140B at the overlap position P1 is greater than the slope angle θ6 of the corresponding second electrode portion; the slope angle θ3 of the light-emitting layer 140B at the overlap position P2 is greater than the slope angle θ7 of the corresponding second electrode portion; and the slope angle θ4 of the light-emitting layer 140C at the overlap position P2 is greater than the slope angle θ8 of the corresponding second electrode portion. As another example, when θ1 is greater than θ2, correspondingly θ5 is greater than θ6, where the difference between θ5 and θ6 is less than the difference between θ1 and θ2. When θ3 is greater than θ4, θ7 is greater than θ8, where the difference between θ7 and θ8 is less than the difference between θ3 and θ4.

[0060] For ease of description, Figure 2 shows three adjacent light-emitting layers 140A, 140B and 140C and a first electrode 120. However, the embodiments of this disclosure are not limited thereto, and the display substrate may have any number of light-emitting layers and a first electrode as needed.

[0061] Figure 3 shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0062] The display substrate 200 shown in Figure 3 is similar to the display substrate 100 shown in Figure 2, except that the thicknesses of adjacent light-emitting layers are different. For the sake of brevity and clarity, the following will mainly focus on the differences.

[0063] As shown in Figure 3, similar to the display substrate 100 shown in Figure 2, the display substrate 200 includes multiple overlapping light-emitting layers 140A', 140B', and 140C'. The surface of the light-emitting layer 140A' away from the substrate 110 intersects with the surface of the adjacent light-emitting layer 140B' away from the substrate 110 at an overlap position P1'; the surface of the light-emitting layer 140B' away from the substrate 110 intersects with the surface of the adjacent light-emitting layer 140C' away from the substrate 110 at an overlap position P2'. Unlike Figure 2, the thicknesses of adjacent light-emitting layers 140A', 140B', and 140C' shown in Figure 3 are different. For example, the thickness T1 of the light-emitting layer 140B' shown in Figure 3 is greater than the thickness T2 of the light-emitting layers 140A' and the thickness T3 of the light-emitting layers 140C' on both sides. The thickness T2 of the light-emitting layer 140A' and the thickness T3 of the light-emitting layer 140C' can be the same or different, and this disclosure does not limit this. Here, the thickness of the light-emitting layer refers to the distance between the highest point of the surface of the light-emitting layer away from the substrate 110 (the upper surface in the figure) and the surface of the first electrode away from the substrate 110 (the upper surface in the figure) in the direction perpendicular to the substrate 110. However, the embodiments of this disclosure are not limited to this, and the thickness of the light-emitting layer can also refer to the average value of the thicknesses of the light-emitting layer in the direction perpendicular to the substrate 110.

[0064] Referring again to Figure 3, light-emitting layer 140A' has a slope angle θ1' at the overlapping position P1', light-emitting layer 140B' has a slope angle θ2' at the overlapping position P1', light-emitting layer 140B' has a slope angle θ3' at the overlapping position P2', and light-emitting layer 140C' has a slope angle θ4' at the overlapping position P2'. According to embodiments of this disclosure, when the thickness difference of the light-emitting layers is greater than a preset value, the slope angle of the light-emitting layers at the overlapping position is related to the thickness of the light-emitting layers. For example, in the example of Figure 3, the difference between thickness T1 and thickness T2, and the difference between thickness T1 and thickness T3, are both greater than the preset value (0.1 μm). In this case, slope angle θ2' is greater than slope angle θ1', and slope angle θ3' is greater than slope angle θ4'. That is, when adjacent light-emitting layers have different thicknesses, the slope angle of the thicker light-emitting layer is greater than the slope angle of the thinner light-emitting layer. In this case, the relationship between the slope angles of the light-emitting layers is independent of the order in which the light-emitting layers are formed.

[0065] Similar to the display substrate 100 shown in FIG. 2, the display substrate 200 also includes a second electrode 150' covering multiple light-emitting layers 140A', 140B', and 140C'. Unlike FIG. 2, the second electrode 150' shown in FIG. 3 has different slope angles at the recesses. For example, at the bottom Q1' of the recess of the second electrode 150', the side of the second electrode 150' near the light-emitting layer 140A' has a slope angle θ5', and the side of the second electrode 150' near the light-emitting layer 140B' has a slope angle θ6', with slope angle θ6' being greater than slope angle θ5'; at the bottom Q2' of the recess of the second electrode 150', the side of the second electrode 150' near the light-emitting layer 140B' has a slope angle θ7', and the side of the second electrode 150' near the light-emitting layer 140C' has a slope angle θ8', with slope angle θ7' being greater than slope angle θ8'. In other words, the trend of the slope angle of the second electrode is consistent with the trend of the slope angle of the underlying light-emitting layer.

[0066] Although Figure 3 shows that the thickness of the middle light-emitting layer 140B' is greater than the thickness of the two side light-emitting layers 140A' and 140C', the embodiments of this disclosure are not limited to this. In other embodiments, the thickness of the left light-emitting layer 140A' may be greater than the thickness of the other two light-emitting layers 140B' and 140C', or the thickness of the right light-emitting layer 140C' may be greater than the thickness of the other two light-emitting layers 140B' and 140A', or the thicknesses of the three light-emitting layers 140A', 140B' and 140C' may be different from each other.

[0067] Figure 4 shows a schematic cross-sectional view of a display substrate according to yet another embodiment of the present disclosure.

[0068] The display substrate 300 shown in Figure 4 is similar to the display substrate 100 shown in Figure 2, except that the display substrate 300 also includes separators. For the sake of brevity and clarity, the following will mainly focus on the differences.

[0069] As shown in FIG4, the display substrate 300 further includes a spacer 160. The spacer 160 is located in the gap between adjacent first electrodes 120 and is covered by pixel defining layer 130. In some embodiments, the spacer 160 is made of an insulating material such as SiO or SiN.

[0070] The height h6 of the surface of the separator 160 away from the substrate 110 is lower than the height h5 of the surface of the first electrode 120 away from the substrate 110. However, the embodiments of this disclosure are not limited to this. In other embodiments, the height h6 of the surface of the separator 160 away from the substrate 110 may also be equal to the height h5 of the surface of the first electrode 120 away from the substrate 110. Here, height h5 refers to the distance between the surface of the first electrode 120 away from the substrate 110 (the upper surface in the figure) and the upper surface of the substrate 110 in the direction perpendicular to the substrate 110, and height h6 refers to the distance between the surface of the separator 160 away from the substrate 110 (the upper surface in the figure) and the upper surface of the substrate 110 in the direction perpendicular to the substrate 110.

[0071] By filling the gap of the first electrode 120 with spacer 160, the light-emitting layers 140A”, 140B”, and 140C” formed later are raised as a whole, reducing the height difference h3’ between the overlapping positions P1”, P2” and the top of the light-emitting layer, thereby further reducing the undulation of the second electrode 150” in the gap. In this way, the voltage drop caused by the distortion of the second electrode morphology is further reduced, and the uniformity of light emission from the display substrate is improved.

[0072] Figure 5A shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0073] The display substrate 400 shown in Figure 5A is similar to the display substrates shown in Figures 2 to 4, except that the display substrate 400 further includes a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer. The descriptions of the substrate, first electrode, light-emitting layer, and second electrode above with reference to Figures 2 to 4 also apply to the embodiment of Figure 5A. For the sake of brevity and clarity, Figure 5A shows the film layer structures in a simplified manner.

[0074] As shown in Figure 5A, the display substrate 400 includes a substrate 110 and a plurality of first electrodes 120, a plurality of light-emitting layers R, G, and B, and a second electrode 150 sequentially stacked on the substrate 110. The light-emitting layers R, G, and B are a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer, respectively. In addition, the display substrate 400 also includes a hole injection layer 171, a hole transport layer 172, an electron transport layer 173, and an electron injection layer 174. The hole injection layer 171 and the hole transport layer 172 are located between the light-emitting layers R, G, and B and the plurality of first electrodes 120, with the hole transport layer 172 located on the side of the hole injection layer 171 away from the substrate 110. The electron transport layer 173 and the electron injection layer 174 are located between the light-emitting layers R, G, and B and the second electrode 150, with the electron injection layer 174 located on the side of the electron transport layer 173 away from the substrate 110.

[0075] In the fabrication process of the aforementioned film layers of the display substrate 400, the light-emitting layers R, G, and B are formed using a silicon-based independent vapor deposition (SBS) process. For example, using a silicon-based mask, a red light-emitting layer R is first deposited on some first electrodes 120, then a green light-emitting layer G is deposited on other first electrodes 120, and finally a blue light-emitting layer B is deposited on the remaining first electrodes 120. The light-emitting layers R, G, and B formed by this SBS process are multiple discrete units. At least one of the hole injection layer 171, hole transport layer 172, electron transport layer 173, and electron injection layer 174 is formed using a full-surface vapor deposition process; therefore, at least one of the hole injection layer 171, hole transport layer 172, electron transport layer 173, and electron injection layer 174 is a continuous layer.

[0076] In other embodiments, as shown in FIG5B, at least one of the hole injection layer 171', hole transport layer 172', electron transport layer 173' and electron injection layer 174' may also include a plurality of discrete units, which correspond one-to-one with a plurality of light-emitting layers R, G and B.

[0077] In some embodiments, the morphology of the surfaces of the hole injection layer and the hole transport layer near the substrate 110 can be substantially the same as the morphology of the surface of the lower first electrode 120 away from the substrate 110. The morphology of the surfaces of the electron transport layer and the electron injection layer near the substrate 110 can be substantially the same as the morphology of the surfaces of the lower light-emitting layers R, G, B away from the substrate 110.

[0078] In some embodiments, the total thickness of the display substrate 400 including the above-described film layers is in the range of 0.05 μm to 0.2 μm.

[0079] Figure 6 shows a schematic cross-sectional view of a display substrate according to another embodiment of the present disclosure.

[0080] The display substrate 500 shown in Figure 6 is similar to the display substrate 400 shown in Figure 5A, except that the display substrate 500 also includes light-emitting layers R2, G2, and B2, a hole injection layer 175, a hole transport layer 176, an electron transport layer 177, an electron injection layer 178, and a charge generation layer CGL. For the sake of brevity and clarity, the following will mainly focus on the differences.

[0081] As shown in Figure 6, the display substrate 500 includes a first light-emitting stack EM1 and a second light-emitting stack EM2. The first light-emitting stack EM1 includes light-emitting layers R1, G1, and B1, a hole injection layer 171, a hole transport layer 172, an electron transport layer 173, and an electron injection layer 174. These structures are identical to those described above with reference to Figure 5A, and will not be repeated here. The second light-emitting stack EM2 includes light-emitting layers R2, G2, and B2, a hole injection layer 175, a hole transport layer 176, an electron transport layer 177, and an electron injection layer 178. Light-emitting layers R1 and R2 can both be a first color, light-emitting layers G1 and G2 can both be a second color, and light-emitting layers B1 and B2 can both be a third color. The first color can be red, the second color can be green, and the third color can be blue.

[0082] The first light-emitting stack EM1 and the second light-emitting stack EM2 are located between the first electrode 120 and the second electrode 150, with the second light-emitting stack EM2 located on the side of the first light-emitting stack EM1 away from the substrate 110. A charge-generating layer CGL is located between the first light-emitting stack EM1 and the second light-emitting stack EM2. The charge-generating layer CGL is used to connect the upper and lower light-emitting layers R1 and R2, the upper and lower light-emitting layers G1 and G2, and the upper and lower light-emitting layers B1 and B2 in series. A hole injection layer 171 and a hole transport layer 172 are located between the light-emitting layers R1, G1, and B1 and the first electrode 120. An electron transport layer 173 and an electron injection layer 174 are located between the light-emitting layers R1, G1, and B1 and the charge-generating layer CGL. A hole injection layer 175 and a hole transport layer 176 are located between the charge-generating layer CGL and the light-emitting layers R2, G2, and B2, with the hole transport layer 176 located on the side of the hole injection layer 175 away from the substrate 110. The electron transport layer 177 and the electron injection layer 178 are located between the light-emitting layers R2, G2 and B2 and the second electrode 150, and the electron injection layer 178 is located on the side of the electron transport layer 177 away from the substrate 110.

[0083] In the fabrication process of the aforementioned film layers of the display substrate 500, similar to the light-emitting layers R1, G1, and B1, the light-emitting layers R2, G2, and B2, and the charge-generating layer CGL are also formed using a silicon-based SBS process. Similar to the hole injection layer 171, hole transport layer 172, electron transport layer 173, and electron injection layer 174, at least one of the hole injection layer 175, hole transport layer 176, electron transport layer 177, and electron injection layer 178 can also be formed using a full-surface evaporation process. Therefore, at least one of the hole injection layer 175, hole transport layer 176, electron transport layer 177, and electron injection layer 178 can be a continuous layer. However, the embodiments of this disclosure are not limited to this. In other embodiments, at least one of the hole injection layer 175, hole transport layer 176, electron transport layer 177, and electron injection layer 178 can also include multiple discrete units as shown in FIG. 5B.

[0084] For example, after forming the light-emitting layers R1, G1, and B1 using the silicon-based SBS process described above, an electron transport layer 173 is formed on the light-emitting layers R1, G1, and B1 by full-surface evaporation, and an electron injection layer 174 is formed on the electron transport layer 173. After forming the electron injection layer 174, a charge generation layer CGL is formed on the electron injection layer 174 by evaporation using the silicon-based SBS process. The charge generation layer CGL includes multiple independent charge generation units, which are located above the light-emitting layers R1, B1, and G1, respectively. Then, a red light-emitting layer R2, a green light-emitting layer G2, and a blue light-emitting layer B2 are formed sequentially using the silicon-based SBS process. The red light-emitting layer R2 is located above the red light-emitting layer R1, the green light-emitting layer G2 is located above the green light-emitting layer G1, and the blue light-emitting layer B2 is located above the blue light-emitting layer B1.

[0085] In this way, multiple light-emitting units arranged side by side are obtained, such as red light-emitting units, green light-emitting units and blue light-emitting units. The red light-emitting unit includes red light-emitting layers R1 and R2 and their corresponding stacked regions in the vertical direction. The green light-emitting unit includes green light-emitting layers G1 and G2 and their corresponding stacked regions in the vertical direction. The blue light-emitting unit includes green light-emitting layers B1 and B2 and their corresponding stacked regions in the vertical direction.

[0086] Figure 7 shows a schematic diagram of the structure of a display substrate according to an embodiment of the present disclosure.

[0087] As shown in FIG. 7, the display substrate 600 includes a substrate 110 and a plurality of first electrodes 120, a plurality of light-emitting layers R, G and B, and a second electrode 150 sequentially stacked on the substrate 110. The first electrodes 120, light-emitting layers R, G and B, and the second electrode 150 can adopt the structure of the first electrode, light-emitting layer, and second electrode as described above with reference to FIG. 2 to 4 (FIG. 7 uses the structure of FIG. 2). In addition, the display substrate 600 also includes an encapsulation layer 180 located on the side of the second electrode 150 away from the substrate 110. As shown in FIG. 7, the encapsulation layer 180 covers the second electrode 150. The morphology of the encapsulation layer 180 can be substantially consistent with the morphology of the second electrode 150. In some embodiments, the encapsulation layer 180 can be a continuous layer.

[0088] The encapsulation layer 180 shown in Figure 7 is a single-layer structure, but the embodiments of this disclosure are not limited to this. In other embodiments, the encapsulation layer 180 may also be a multi-layer structure. In some embodiments, the encapsulation layer 180 may be made of organic and / or inorganic materials, for example, it may have a three-layer structure such as SiN+Al2O3+SiN.

[0089] Referring again to FIG7, in some embodiments, the display substrate 600 may further include a planarization layer 190 covering the encapsulation layer 180. The planarization layer 190 may be made of organic and / or inorganic materials, and this disclosure does not limit this. The morphology of the surface of the planarization layer 190 near the substrate 110 may be substantially the same as that of the encapsulation layer 180, and the surface of the planarization layer 190 away from the substrate 110 may be a flat surface, thereby achieving the effect of planarization.

[0090] In some embodiments, the display substrate 600 may further include a plurality of microlenses LN located on the side of the planarization layer 190 away from the substrate 110. Each of the plurality of microlenses LN corresponds one-to-one with a plurality of light-emitting layers R, G, and B. Here, "one-to-one correspondence" means that each light-emitting layer has a corresponding microlens on its side away from the substrate 110. The arrangement of the plurality of microlenses LN can be consistent with that of the plurality of light-emitting layers R, G, and B, such as a strip arrangement, a dot arrangement, a triangular arrangement, or a mosaic arrangement. In this way, the first electrode, the light-emitting layer, and the second electrode, together with their corresponding microlenses, form a light-emitting structure, and the light emitted by the light-emitting layer is focused by the microlenses to improve brightness. In some embodiments, the microlenses LN may be made of an organic transparent material, and this disclosure does not limit this.

[0091] This disclosure also provides a method for manufacturing a display substrate, comprising: forming a plurality of first electrodes on a substrate, with gaps between adjacent first electrodes; forming a plurality of light-emitting layers corresponding one-to-one with the plurality of first electrodes on the side of the plurality of first electrodes away from the substrate, wherein the projection of each first electrode on the substrate is located within the projection of the corresponding light-emitting layer on the substrate, wherein adjacent light-emitting layers have different colors and overlap in the gaps between the corresponding adjacent first electrodes, and the adjacent light-emitting layers have a first slope angle and a second slope angle at the overlapping position, wherein the first slope angle and the second slope angle are not zero and the first slope angle and the second slope angle are different from each other, wherein the overlapping position is the position where the surfaces of the adjacent light-emitting layers on the side away from the substrate intersect; and forming a second electrode covering the plurality of light-emitting layers, wherein the second electrode has a recess at the overlapping position.

[0092] In some embodiments, forming a plurality of light-emitting layers corresponding one-to-one with the plurality of first electrodes includes: sequentially forming a first-color light-emitting layer, a second-color light-emitting layer, and a third-color light-emitting layer on the plurality of first electrodes using a silicon-based independent vapor deposition (SBS) process, such that in the gap between adjacent first electrodes, the second-color light-emitting layer covers the first-color light-emitting layer, and the third-color light-emitting layer covers the second-color light-emitting layer.

[0093] In some embodiments, the method further includes forming a pixel defining layer before forming the plurality of light-emitting layers. The pixel defining layer has openings corresponding one-to-one with the plurality of first electrodes, the edge regions of each first electrode being covered by the pixel defining layer, and the central regions being exposed through the corresponding openings.

[0094] In some embodiments, the method further includes filling the gap between adjacent first electrodes with a spacer before forming the pixel defining layer.

[0095] Figures 8A to 8F illustrate the manufacturing process of a display substrate according to an embodiment of the present disclosure.

[0096] As shown in FIG8A, a plurality of first electrodes 120 are formed on a substrate 110, and there are gaps between adjacent first electrodes among the plurality of first electrodes 120. In some embodiments, the material of the first electrode 120 includes ITO or TiAg / ITO.

[0097] Next, as shown in FIG8B, a pixel defining layer 130 is formed on the side of the plurality of first electrodes 120 away from the substrate 110. The pixel defining layer 130 has an opening OP corresponding to the plurality of first electrodes 120 one by one. The edge region of each first electrode 120 is covered by the pixel defining layer 130, and the central region is exposed through the corresponding opening OP.

[0098] Next, as shown in Figures 8C to 8E, a first-color light-emitting layer 140A, a second-color light-emitting layer 140B, and a third-color light-emitting layer 140C are sequentially formed on multiple first electrodes 120 using a silicon-based independent vapor deposition (SBS) process. In the SBS process, a silicon-based ultra-fine mask (mask) made of a Si wafer is used to deposit the light-emitting layers. This silicon-based ultra-fine mask is obtained by etching ultra-fine mesh holes on a Si wafer using exposure and dry etching techniques. First, as shown in Figure 8C, a first-color light-emitting layer 140A is formed on the leftmost first electrode 120. Next, as shown in Figure 8D, a second-color light-emitting layer 140B is formed on the middle first electrode 120 using the SBS process. The second-color light-emitting layer 140B forms a gap between the leftmost first electrode 120 and the middle first electrode 120, covering the first-color light-emitting layer 140A. Next, as shown in Figure 8E, a third-color light-emitting layer 140C is formed on the rightmost first electrode 120 among the multiple first electrodes 120 using a silicon-based independent vapor deposition (SBS) process. The third-color light-emitting layer 140C forms a second-color light-emitting layer 140B in the gap between the middle first electrode 120 and the rightmost first electrode 120. At this point, the fabrication of multiple light-emitting layers 140A, 140B, and 140C, each corresponding to one of the multiple first electrodes 120, is complete.

[0099] Next, as shown in FIG8F, a second electrode 150 is formed covering multiple light-emitting layers 140A, 140B and 140C, and the formed second electrode 150 has a recess at the overlapping position of the multiple light-emitting layers 140A, 140B and 140C.

[0100] In some embodiments, before forming the pixel defining layer 130 shown in FIG8B, an insulating material such as SiO or SiN may be filled in the gap between adjacent first electrodes 120, and then the operations described above with reference to FIG8C to 8F are performed to obtain a display substrate structure with separator 160 as shown in FIG4.

[0101] In some embodiments, before forming the respective light-emitting layers as shown in FIG8C, a hole injection layer 171 may be formed on the structure shown in FIG8B, and a hole transport layer 172 may be formed on the hole injection layer 171. Next, the operations shown in FIGS8C to 8E are performed to form three different colored light-emitting layers 140A, 140B, and 140C on the hole transport layer 172. Next, before forming the second electrode as shown in FIG8F, an electron transport layer 173 may be formed on the structure shown in FIG8E, and an electron injection layer 174 may be formed on the electron transport layer 173. Then, the operations shown in FIG8F are performed to form the second electrode 150 on the electron injection layer 174. Thus, the display substrate structure shown in FIG5A or FIG5B is obtained.

[0102] In some embodiments, after forming the electron injection layer 174 and before forming the second electrode 150, the charge generation layer CGL, hole injection layer 175, hole transport layer 176, light-emitting layers R2, G2 and B2, electron transport layer 177 and electron injection layer 178 may be formed sequentially as described above. Then, the operation shown in FIG8F is performed to form the second electrode 150. Thus, the display substrate structure shown in FIG6 is obtained.

[0103] Although the above illustration uses three first electrodes and three corresponding light-emitting layers as an example, this is merely for ease of description. The number of first electrodes and light-emitting layers, as well as the color of the light-emitting layers, can be set as needed. For example, red light-emitting layers can be formed on some of the multiple first electrodes, then green light-emitting layers can be formed on some other first electrodes, and finally blue light-emitting layers can be formed on the remaining first electrodes. The color and position of the light-emitting layers can be set so that the light-emitting layers above adjacent first electrodes have different colors.

[0104] This disclosure also provides a display device. The display device includes a display substrate as described above.

[0105] The display device may include any device or product with display functionality. For example, the display device may be a smartphone, mobile phone, e-book reader, desktop computer (PC), laptop PC, netbook PC, personal digital assistant (PDA), portable multimedia player (PMP), digital audio player, mobile medical device, camera, wearable device (e.g., head-mounted device, electronic clothing, electronic bracelet, electronic necklace, electronic accessory, electronic tattoo, or smartwatch), television set, etc.

[0106] Those skilled in the art will understand that the embodiments described above are exemplary and can be improved upon. The structures described in the various embodiments can be freely combined without causing any conflict in structure or principle.

[0107] After a detailed description of the preferred embodiments of this disclosure, those skilled in the art will clearly understand that various changes and modifications can be made without departing from the scope and spirit of the appended claims, and that this disclosure is not limited to the implementation of the exemplary embodiments described in the specification.

Claims

1. A display substrate, comprising: Substrate; A plurality of first electrodes are located on the substrate, and a gap is provided between adjacent first electrodes; Multiple light-emitting layers are located on the side of the multiple first electrodes away from the substrate, and correspond one-to-one with the multiple first electrodes. The projection of the first electrode on the substrate is located within the projection of the corresponding light-emitting layer on the substrate. Adjacent light-emitting layers have different colors and overlap in the gap between corresponding adjacent first electrodes. The adjacent light-emitting layers have a first slope angle and a second slope angle at the overlapping position. The first slope angle and the second slope angle are not zero and are different from each other. The overlapping position is the position where the surfaces of the adjacent light-emitting layers on the side away from the substrate intersect. The second electrode covers the plurality of light-emitting layers, and the second electrode has a recess at the overlapping position.

2. The display substrate according to claim 1, further comprising: A pixel defining layer has openings corresponding to the plurality of first electrodes. The edge regions of each first electrode are covered by the pixel defining layer and the central regions are exposed through the corresponding openings. The plurality of light-emitting layers are located on the side of the pixel defining layer away from the substrate.

3. The display substrate according to claim 2, wherein, The light-emitting layer includes a flat portion located above the opening of the pixel defining layer and a curved portion surrounding the flat portion. In a cross-section perpendicular to the substrate, the width of the curved portion in the direction parallel to the substrate is greater than the width of the flat portion in the direction parallel to the substrate.

4. The display substrate according to claim 1, wherein, One of the adjacent light-emitting layers has the first slope angle at the overlapping position, and the other light-emitting layer has the second slope angle at the overlapping position; wherein the thickness difference between the adjacent light-emitting layers is less than or equal to a preset value, the edge of the one light-emitting layer is covered by the other light-emitting layer, and the first slope angle is greater than the second slope angle.

5. The display substrate according to claim 1, wherein, One of the adjacent light-emitting layers has the first slope angle at the overlapping position, and the other light-emitting layer has the second slope angle at the overlapping position; Wherein, the thickness difference between adjacent light-emitting layers is greater than a preset value, the thickness of one light-emitting layer is greater than the thickness of the other light-emitting layer, and the first slope angle is greater than the second slope angle.

6. The display substrate according to claim 4 or 5, wherein, At the bottom of the recess of the second electrode, the second electrode has a third slope angle on the side facing the one light-emitting layer and a fourth slope angle on the side facing the other light-emitting layer. The third slope angle is smaller than the first slope angle, the fourth slope angle is smaller than the second slope angle, and the difference between the third slope angle and the fourth slope angle is smaller than the difference between the first slope angle and the second slope angle.

7. The display substrate according to any one of claims 4 to 6, wherein, The preset value is in the range of 0.05μm to 0.15μm.

8. The display substrate according to any one of claims 1 to 7, wherein, There is a first height difference between the lowest point of the surface of the second electrode away from the substrate and the top of the second electrode, and a second height difference between the lowest point of the surface of the second electrode close to the substrate and the top of the second electrode, wherein the top of the second electrode is the highest point of the surface of the second electrode away from the substrate, and the ratio of the first height difference to the second height difference is in the range of 0.05 to 0.

5.

9. The display substrate according to any one of claims 1 to 8, wherein, There is a first height difference between the lowest point of the surface of the second electrode away from the substrate and the top of the second electrode, and there is a third height difference between the overlapping position of the adjacent light-emitting layer and the surface of the first electrode away from the substrate, the third height difference being greater than the first height difference.

10. The display substrate according to any one of claims 1 to 9, wherein, The overlapping position does not overlap with the center line of the gap, wherein the center line of the gap is equidistant from the first electrodes on both sides of the gap.

11. The display substrate according to claim 10, wherein, The bottom of the recess of the second electrode is closer to the center line of the gap than the overlapping position.

12. The display substrate according to any one of claims 1 to 11, further comprising: Hole injection layer, hole transport layer, electron transport layer, and electron injection layer. The hole injection layer and the hole transport layer are located between the plurality of light-emitting layers and the plurality of first electrodes, and the hole transport layer is located on the side of the hole injection layer away from the substrate. The electron transport layer and the electron injection layer are located between the plurality of light-emitting layers and the second electrode, with the electron injection layer located on the side of the electron transport layer away from the substrate.

13. The display substrate according to claim 12, wherein, At least one of the hole injection layer, hole transport layer, electron transport layer and electron injection layer is a continuous layer.

14. The display substrate according to claim 12, wherein, At least one of the hole injection layer, hole transport layer, electron transport layer and electron injection layer includes a plurality of discrete units, and the plurality of discrete units correspond one-to-one with the plurality of light-emitting layers.

15. The display substrate according to any one of claims 1 to 14, further comprising a spacer located in the gap between adjacent first electrodes and covered by a pixel defining layer.

16. The display substrate according to claim 15, wherein, The surface height of the isolator on the side away from the substrate is lower than or equal to the surface height of the first electrode on the side away from the substrate.

17. The display substrate according to any one of claims 1 to 16, wherein, The first slope angle and the second slope angle are in the range of 15° to 90°.

18. The display substrate according to any one of claims 1 to 17, wherein, The width of the gap is in the range of 0.2 μm to 1.3 μm.

19. The display substrate according to any one of claims 1 to 18, wherein, The thickness of the light-emitting layer is in arrive Between them, the thickness difference between different color emitting layers is less than 20. The display substrate according to any one of claims 1 to 19, wherein, The thickness of the second electrode is arrive Within the range.

21. The display substrate according to any one of claims 1 to 20, wherein, The plurality of light-emitting layers include a first color light-emitting layer, a second color light-emitting layer, and a third color light-emitting layer, wherein the first color light-emitting layer, the second color light-emitting layer, and the third color light-emitting layer are formed by a silicon-based independent vapor deposition process, the second color light-emitting layer is formed after the first color light-emitting layer, and the third color light-emitting layer is formed after the second color light-emitting layer.

22. The display substrate according to any one of claims 1 to 21, further comprising an encapsulation layer covering the second electrode.

23. The display substrate according to claim 22, further comprising: A planarization layer, covering the encapsulation layer; Multiple microlenses are located on the side of the planarization layer away from the substrate, and each corresponds to one of the multiple light-emitting layers.

24. A method for manufacturing a display substrate as described in any one of claims 1 to 23, comprising: A plurality of first electrodes are formed on the substrate, with gaps between adjacent first electrodes; Multiple light-emitting layers are formed on the side of the plurality of first electrodes away from the substrate, each corresponding to one of the plurality of first electrodes. The projection of each first electrode on the substrate is located within the projection of the corresponding light-emitting layer on the substrate. Adjacent light-emitting layers have different colors and overlap in the gap between corresponding adjacent first electrodes. The adjacent light-emitting layers have a first slope angle and a second slope angle at the overlapping position. The first slope angle and the second slope angle are not zero and are different from each other. The overlapping position is the position where the surfaces of the adjacent light-emitting layers on the side away from the substrate intersect. A second electrode is formed to cover the plurality of light-emitting layers, and the second electrode has a recess at the overlapping position.

25. The method according to claim 24, wherein, The formation of multiple light-emitting layers corresponding one-to-one with the plurality of first electrodes includes: A first-color light-emitting layer, a second-color light-emitting layer, and a third-color light-emitting layer are sequentially formed on the plurality of first electrodes using a silicon-based independent vapor deposition (SBS) process, such that in the gap between adjacent first electrodes, the second-color light-emitting layer covers the first-color light-emitting layer, and the third-color light-emitting layer covers the second-color light-emitting layer.

26. The method according to claim 24 or 25, further comprising: Before forming the plurality of light-emitting layers, a pixel defining layer is formed, the pixel defining layer having an opening corresponding to each of the plurality of first electrodes, the edge region of each first electrode being covered by the pixel defining layer, and the central region being exposed through the corresponding opening.

27. The method of claim 26, further comprising: Before forming the pixel defining layer, an insulator is filled in the gap between adjacent first electrodes.

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