Display substrate and display device

Abstract

The utility model provides a display substrate and a display device. The display substrate comprises a substrate body and a light-emitting device layer arranged on the substrate body. The light-emitting device layer comprises a first electrode layer, a first pixel defining layer, a light-emitting function layer and a second electrode layer which are stacked on the substrate so as to form a plurality of light-emitting devices. The first electrode layer comprises first electrodes of the light-emitting devices and partition structures spaced from the first electrodes, the partition structures are located between every two adjacent light-emitting devices, and each partition structure comprises a first partition part, a second partition part and a third partition part which are arranged in a stacked mode in the direction perpendicular to the substrate; the third partition portion is provided with a first protruding portion exceeding the second partition portion in the direction facing the adjacent light-emitting device. The light-emitting functional layer comprises a plurality of sub-functional layers, and at least one of the sub-functional layers is disconnected at the position where the partition structure is located.

Description

Technical Field

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

[0002] Organic Light Emitting Diode (OLED) display devices have the advantages of being thin and light, having a wide color gamut, fast response speed, and high resolution, and have become a research hotspot. As OLED display devices are increasingly used, people's requirements for their display effects are also gradually increasing.

[0003] An OLED display device includes a plurality of OLED devices, some of which have common film layers with high charge mobility, which are prone to generate lateral leakage current, resulting in crosstalk between adjacent sub-pixels, thereby affecting the display effect. Utility Model Content

[0004] Some embodiments of the present disclosure provide a display substrate and a display device to improve the crosstalk problem between adjacent sub-pixels.

[0005] In a first aspect, some embodiments of the present disclosure provide a display substrate, comprising: a base substrate and a light-emitting device layer disposed on the base substrate, wherein the light-emitting device layer comprises a first electrode layer, a first pixel defining layer, a light-emitting functional layer and a second electrode layer stacked on the base substrate to form a plurality of light-emitting devices. The first electrode layer comprises a first electrode of the light-emitting device and a partition structure spaced apart from the first electrode, the partition structure is located between adjacent light-emitting devices, the partition structure comprises a first partition portion, a second partition portion and a third partition portion stacked in a direction perpendicular to the base substrate, the third partition portion having a first protrusion exceeding the second partition portion in a direction toward the adjacent light-emitting device. The first pixel defining layer has a plurality of first openings and a plurality of second openings, the plurality of first openings being used to define the light-emitting area of ​​the light-emitting device, the orthographic projection of the partition structure on the base substrate being located within the orthographic projection range of the second opening on the base substrate. The light-emitting functional layer comprises a plurality of sub-functional layers, at least one of the plurality of sub-functional layers being disconnected at the location where the partition structure is located.

[0006] In some embodiments, the display substrate further includes: a driving circuit layer and a flat layer located between the driving circuit layer and the first electrode layer. The flat layer includes: a main body and a first supporting portion arranged on a side of the main body away from the base substrate, a step structure is formed between the first supporting portion and the main body, the first partition portion is located on a side of the first supporting portion away from the base substrate, and the orthographic projection on the base substrate at least partially overlaps with the orthographic projection of the first supporting portion on the base substrate, the first partition portion has a second protrusion extending beyond the first supporting portion in a direction toward the adjacent light-emitting device, and a gap is formed between the second protrusion and the main body in a direction perpendicular to the base substrate.

[0007] In some embodiments, the planar layer also includes: a second supporting portion arranged on the side of the main body away from the base substrate, the first supporting portion and the second supporting portion extend beyond the main body in a direction perpendicular to the base substrate, the first electrode is located on the side of the second supporting portion away from the base substrate, and its orthographic projection on the base substrate at least partially overlaps with the orthographic projection of the second supporting portion on the base substrate, and the first electrode has a third protrusion extending beyond the second supporting portion in a direction toward the adjacent partition structure.

[0008] In some embodiments, the display substrate also includes: a first power signal line and a second power signal line, which are located on the side of the first electrode layer close to the base substrate, the first power signal line transmits a first power voltage which is less than the second power voltage transmitted by the second power signal line, the partition structure has a conductive property, and the partition structure is electrically connected to the first power signal line.

[0009] In some embodiments, the display substrate also includes: a metal routing layer provided with the first power signal line, located on the side of the first electrode layer close to the base substrate; and a passivation layer located on the side of the metal routing layer close to the first electrode layer, and the partition structure is electrically connected to the first power signal line through a via hole penetrating the passivation layer.

[0010] In some embodiments, the display substrate further includes: a second pixel defining layer, which is located on the side of the first pixel defining layer close to the base substrate, and the material of the second pixel defining layer includes: an inorganic insulating material. The second pixel defining layer conformally covers the partition structure, and the orthographic projection of the partition structure on the base substrate is located within the orthographic projection range of the second pixel defining layer on the base substrate. The second pixel defining layer has a plurality of third openings, and the orthographic projections of the third openings on the base substrate at least partially overlap with the orthographic projections of the first openings on the base substrate to expose at least a portion of the first electrode. In some embodiments, along a direction perpendicular to the base substrate, the thickness of the second pixel defining layer is less than half of the thickness of the second partition portion, and is less than the width of the first protrusion in the direction toward the adjacent light-emitting device.

[0011] In some embodiments, the material of the first pixel defining layer includes an organic material. In some embodiments, the slope angle of the side surface of the first pixel defining layer close to the second opening is 20° to 30°, and the distance from the top end of the side surface to the center of the second opening is greater than the distance from the bottom end of the side surface to the center of the second opening.

[0012] In some embodiments, the first electrode is a multi-layer composite structure, and the partition structure includes the same number and material of film layers as the first electrode.

[0013] In some embodiments, the first electrode and the partition structure respectively include: a stacked metal electrode layer and a protective electrode layer, the metal electrode layer includes at least a stacked first sublayer and a second sublayer, the protective electrode layer is located on a side of the second sublayer away from the first sublayer, the material of the first sublayer includes a first metal, and the material of the second sublayer includes a second metal. The first partition portion in the partition structure includes the first sublayer, the second partition portion includes the second sublayer, and the third partition portion includes the protective electrode layer.

[0014] In some embodiments, the metal electrode layer further includes a third sublayer stacked between the second sublayer and the protective electrode layer, the third partition portion further includes the third sublayer, and a material of the third sublayer includes the first metal.

[0015] In some embodiments, the protective electrode layer in the first electrode is located on the side of the metal electrode layer away from the base substrate and wraps the side of the metal electrode layer; the protective electrode layer in the partition structure is located on the side of the metal electrode layer away from the base substrate and its edge is flush with the edge of the third partition portion.

[0016] In some embodiments, the plurality of sub-functional layers include a charge generation layer and a first light-emitting layer and a second light-emitting layer stacked on both sides of the charge generation layer, and the charge generation layer is disconnected at a location where the partition structure is located.

[0017] In a second aspect, some embodiments of the present disclosure provide a display device comprising the display substrate described in the first aspect.

[0018] The display substrate provided by some embodiments of the present disclosure has a partition structure on the same layer as the first electrode disposed between adjacent light-emitting devices, and the third partition portion of the partition structure has a first protrusion exceeding the second partition portion in the direction toward the adjacent light-emitting device, that is, the second partition portion is retracted compared to the third partition portion, so that the partition structure forms an undercut structure on the side facing the adjacent light-emitting device, thereby being able to effectively isolate at least one sub-functional layer in the light-emitting functional layer formed on the partition structure, which is beneficial to intercepting laterally transmitted carriers and reducing crosstalk between adjacent sub-pixels.

[0019] The above description is only an overview of the technical solution provided by the embodiment of the present disclosure. In order to more clearly understand the technical means of the embodiment of the present disclosure, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present disclosure more obvious and easy to understand, the specific implementation method of the embodiment of the present disclosure is listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present disclosure. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0021] Figure 1 A schematic plan view of a display substrate according to some embodiments of the present disclosure is shown;

[0022] Figure 2A A schematic diagram showing the structure of a display substrate according to some embodiments of the present disclosure is shown;

[0023] Figure 2B Shows Figure 2A Enlarged view of the middle A1 region;

[0024] Figure 2C Shows Figure 2A Micrograph of the partition structure in ;

[0025] Figure 2D A schematic structural diagram of a first electrode in some embodiments of the present disclosure is shown;

[0026] Figure 2E Shows Figure 2A Partition effect diagram of the partition structure in;

[0027] Figure 3 A plan view showing a partition structure of some embodiments of the present disclosure;

[0028] Figure 4A Showing schematic structural diagrams of display substrates in other embodiments of the present disclosure;

[0029] Figure 4B Shows Figure 4A A magnified view of the A2 region in the middle;

[0030] Figure 5A A schematic diagram showing the structure of a display substrate in some further embodiments of the present disclosure is shown;

[0031] Figure 5B Shows Figure 5A Enlarged view of the middle A3 area;

[0032] Fig. 6A A schematic diagram showing the structure of a display substrate according to some other embodiments of the present disclosure is shown;

[0033] Figure 6B Shows Fig. 6A Enlarged view of the middle A4 area;

[0034] Fig. 7A Showing schematic structural diagrams of display substrates of other embodiments of the present disclosure;

[0035] Figure 7B Shows Fig. 7A Enlarged view of the middle A5 area;

[0036] Fig. 8A Showing schematic structural diagrams of display substrates of other embodiments of the present disclosure;

[0037] Figure 8B Shows Fig. 8A Enlarged view of the middle A6 region;

[0038] Fig.9A Showing schematic structural diagrams of display substrates of other embodiments of the present disclosure;

[0039] Fig. 9B Shows Fig.9A Enlarged view of the middle A7 region;

[0040] Fig. 10A Showing schematic structural diagrams of display substrates of other embodiments of the present disclosure;

[0041] Fig. 10B Shows Fig. 10A Enlarged view of the middle A8 region;

[0042] Fig.11A Showing schematic structural diagrams of display substrates of other embodiments of the present disclosure;

[0043] Fig. 11B Shows Fig.11A A magnified image of the middle A9 region;

[0044] Fig.12 A schematic diagram showing the structure of a display substrate according to some embodiments of the present disclosure is shown;

[0045] Fig.13 A flow chart showing a method for preparing a display substrate according to some embodiments of the present disclosure is shown;

[0046] Fig.14 A partial process flow chart showing a display substrate according to some embodiments of the present disclosure is shown;

[0047] Fig.15A A micrograph showing an undercut structure formed between the first partition portion and the flat layer;

[0048] Fig. 15B A micrograph of an ITO / Ti / Al / Ti partition structure formed after etching away part of Al by development is shown;

[0049] Fig.16 A schematic structural diagram of a display device according to some embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0050] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that the term "plurality" appearing herein includes two or more than two situations.

[0051] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of variation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0052] As used herein, "parallel", "perpendicular", and "equal" include the situations described and situations similar to the situations described, and the range of the similar situations is within the 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 a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism may be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity may also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality may be, for example, the difference between the two equalities is less than or equal to 5% of either one.

[0053] It should be understood that when a layer or element is referred to as being on another layer or substrate, it may be that the layer or element is directly on the other layer or substrate, or there may be an intermediate layer between the layer or element and the other layer or substrate. The "same layer" in the embodiments of the present disclosure refers to the relationship between multiple film layers formed by the same material after the same step (e.g., a one-step patterning process).

[0054] Display devices using a double-layer luminescence (Tandem EL) design have the advantages of long life, low power consumption, and high brightness, and have been widely used. The OLED light-emitting device in this display device has two light-emitting layers, and a charge generation layer (CGL) is arranged between the two light-emitting layers to generate carriers and inject them into the two light-emitting layers respectively, thereby improving the luminous brightness. However, for high-resolution display products, since the charge generation layer has a high charge mobility, and the common film layer in the organic light-emitting functional layer of adjacent sub-pixels is connected, it is easy for laterally transmitted carriers to exist, resulting in crosstalk between adjacent sub-pixels, thereby affecting the display effect.

[0055] Therefore, some embodiments of the present disclosure provide a display substrate, which can achieve the isolation of the film layer with high charge mobility in the EL layer by setting a partition structure in the same layer as the first electrode between adjacent light-emitting devices, which is beneficial to stop the lateral transmission of carriers and reduce the crosstalk between adjacent sub-pixels. Below, the display substrate provided by the embodiments of the present disclosure is described in detail with reference to the accompanying drawings.

[0056] Figure 1 FIG. 2 shows a schematic plan view of a display substrate of some embodiments of the present disclosure. Figure 1As shown, the display substrate 10 includes: a display area AA and a non-display area SA. The non-display area SA is located on at least one side of the display area AA. For example, the non-display area SA can be located on one side of the display area AA, or can also be located on multiple sides of the display area AA, such as the non-display area SA can surround the outside of the display area AA. It should be noted that Figure 1 The shape of the display area and the shape of the non-display area of ​​the display substrate shown in the figure are for illustration only and are not intended to be limiting. The actual shape is determined according to the needs of the display product.

[0057] The display area AA may include a plurality of pixels P arranged in an array. Figure 1 As shown, the display area AA is provided with a plurality of pixels P arranged in an array in a first direction and a second direction. Figure 1 The X-axis in the figure is represented by Figure 1 For example, a plurality of pixels P may be arranged into M rows and N columns, where M and N are integers greater than or equal to 2. Figure 1 Only a few pixels P are shown as an arrangement example, and ellipsis indicates other pixels not shown. The first direction X is the pixel row direction, and the second direction Y is the pixel column direction. The first direction X and the second direction Y intersect, such as being perpendicular to each other.

[0058] For example, each pixel P may include multiple sub-pixels, each of which may include a light-emitting device and a pixel driving circuit for driving the light-emitting device. Each sub-pixel may display a single color, such as a red sub-pixel displays red, a green sub-pixel displays green, and a blue sub-pixel displays blue. The brightness (grayscale) of sub-pixels of different colors in each pixel can be adjusted, and multiple colors can be displayed by color combination and superposition, thereby achieving full-color display.

[0059] It should be noted that the type, quantity and arrangement of sub-pixels included in each pixel P can be set according to the needs of the actual product. For example, each pixel P may include: two green sub-pixels, one blue sub-pixel and one red sub-pixel. For example, the shapes of the above-mentioned multiple sub-pixels can be a single graphic or a combination of multiple graphics such as circle, ellipse, triangle, quadrilateral, prism, pentagon and hexagon.

[0060] Figure 2A Schematic diagrams showing the structure of a display substrate 10 according to some embodiments of the present disclosure are shown. Figure 2B Shows Figure 2A A magnified image of the A1 region. Figure 2C Shows Figure 2A Micrograph of the partition structure in Figure 2D shows a schematic structural diagram of the first electrode in some embodiments of the present disclosure, Figure 2E Shows Figure 2AThe partition effect diagram of the partition structure in the figure. Figure 2A As shown, the display substrate 10 includes: a base substrate 100 and a light emitting device layer arranged on the base substrate 100 .

[0061] For example, the substrate 100 may be a flexible substrate. The flexible substrate may include, for example, a PI (Polyimide) substrate, a PET (Polyethylene Terephthalate) substrate, or a PEN (Polyethylene naphthalate two formic acid glycol ester) substrate. In this case, the display substrate 10 may be a flexible display substrate.

[0062] For another example, the substrate 100 may be a rigid substrate. The rigid substrate may include, for example, a glass substrate, an ultra-thin glass (UTG) substrate, a PMMA (Polymethyl methacrylate) substrate, or a silicon substrate. In this case, the display substrate 10 may be a rigid display substrate.

[0063] It should be noted that the base substrate 100 may be a one-layer structure or a multi-layer structure. For example, the base substrate 100 may include at least one flexible substrate and at least one buffer layer, and the flexible substrate and the buffer layer are alternately stacked.

[0064] The light emitting device layer includes a first electrode layer 130 , a first pixel defining layer 141 , a light emitting function layer 150 and a second electrode layer 160 stacked on the base substrate 100 to form a plurality of light emitting devices.

[0065] The first electrode layer 130 includes a first electrode 131 of a light emitting device and a partition structure 132 spaced apart from the first electrode 131. The partition structure 132 is located between adjacent light emitting devices. "Adjacent light emitting devices" means that no other light emitting devices are arranged between two light emitting devices. The light emitting functional layer 150 includes a plurality of sub-functional layers, at least one of which is disconnected at the location where the partition structure 132 is located.

[0066] like Figure 2B and Figure 2C As shown, the partition structure 132 may include a first partition portion 201, a second partition portion 202 and a third partition portion 203 stacked in a direction perpendicular to the base substrate 100, and the third partition portion 203 has a first protrusion extending beyond the second partition portion 202 in a direction toward an adjacent light-emitting device.

[0067] That is to say, the second partition portion 202 of the partition structure 132 is retracted compared to the third partition portion 203, so that the partition structure 132 forms an undercut structure on the side facing the adjacent light-emitting device, thereby disconnecting at least one sub-functional layer in the light-emitting functional layer 150 subsequently formed on the partition structure 132, which is beneficial to intercepting the laterally transmitted carriers and reducing the crosstalk between adjacent sub-pixels.

[0068] For example, in order to ensure the stability of the undercut structure, the width d of the first protrusion in the direction toward the adjacent light-emitting device, that is, the inward distance of the second partition portion 202 compared to the third partition portion 203, can be 0.3 microns to 0.5 microns, such as 0.3 microns, 0.4 microns or 0.5 microns, etc., which is determined according to the actual product needs and process conditions, and the present disclosure will not list them one by one.

[0069] It should be noted that the partition structure 132 and the first electrode 131 are in the same layer. For example, the pattern of the partition structure 132 and the pattern of the first electrode 131 can be formed by the same patterning process and the same etching process.

[0070] In some embodiments, in order to form a partition structure 132 in the same layer as the first electrode 131, the first electrode 131 is a multilayer composite structure. The partition structure 132 includes the same number of film layers and materials as the first electrode 131. In some examples, the first electrode 131 may include metal materials such as magnesium (Mg), silver (Ag), copper (Cu), aluminum (Al), titanium (Ti) and molybdenum (Mo). In other examples, the first electrode 131 may also include alloy materials of the above metals, such as aluminum neodymium alloy (AlNd) or molybdenum niobium alloy (MoNb). In some other examples, the first electrode 131 may also be a stack structure formed by the above metals and transparent conductive materials. The transparent conductive material may be, for example, any one of transparent conductive oxide thin film materials such as ITO (Indium tin oxide) and IZO (Indium zinc oxide).

[0071] In some embodiments, the first electrode 131 may include: a stacked metal electrode layer 1300 and a protective electrode layer 1304. Correspondingly, the partition structure 132 also includes: a stacked metal electrode layer 1300 and a protective electrode layer 1304. Figure 2DAs shown, the protective electrode layer 1304 in the first electrode 131 is located on the side of the metal electrode layer 1300 away from the base substrate 100, and wraps the side of the metal electrode layer 1300. This can prevent the metal electrode layer 1300 in the first electrode 131 from being corroded and causing display abnormalities. The protective electrode layer 1304 in the partition structure 132 is also located on the side of the metal electrode layer 1300 away from the base substrate 100, and the edge is flush with the edge of the third partition portion 203, as shown in FIG. Figure 2B As shown. The term “flush” here should be understood in a broad sense, including completely flush and approximately flush, that is, flush within an acceptable error range. After the partition structure pattern is formed, it is necessary to further etch part of the metal film layer of the partition structure pattern from the side so that the second partition portion 202 in the partition structure 132 formed in the end is retracted compared to the third partition portion 203. Therefore, unlike the first electrode 131, the side of the metal electrode layer 1300 in the partition structure 132 is not wrapped by the protective electrode layer 1304.

[0072] The metal electrode layer 1300 at least includes a first sublayer 1301 and a second sublayer 1302 which are stacked, and a protective electrode layer 1304 is located on a side of the second sublayer 1302 which is away from the first sublayer 1301. At this time, the first partition portion 201 in the partition structure 132 includes the first sublayer 1301, the second partition portion 202 includes the second sublayer 1302, and the third partition portion 203 includes the protective electrode layer 1304. The material of the first sublayer 1301 includes the first metal, and the material of the second sublayer 1302 includes the second metal. In this way, the selectivity of the etching process can be utilized to select only the second metal to be etched, and the first metal and the protective electrode layer 1304 are not etched, so that the third partition portion 203 of the partition structure 132 has a first protrusion that exceeds the second partition portion 202 in the direction toward the adjacent light-emitting device.

[0073] For example, when the metal electrode layer 1300 includes a first sublayer 1301 and a second sublayer 1302, the first metal may be molybdenum and the second metal may be aluminum. Taking the material of the protective electrode layer 1304 including ITO as an example, the first electrode 131 and the partition structure 132 may be a stacked composite structure of Mo / Al / ITO.

[0074] In some embodiments, in addition to the first sublayer 1301 and the second sublayer 1302, the metal electrode layer 1300 further includes a third sublayer 1303, and the third sublayer 1303 is stacked between the second sublayer 1302 and the protective electrode layer 1304. In this case, the third partition portion 203 may include the third sublayer 1303 and the protective electrode layer 1304. The material of the third sublayer 1303 may include the first metal.

[0075] For example, when the metal electrode layer 1300 includes a first sublayer 1301, a second sublayer 1302 and a third sublayer 1303, the first metal may be titanium, the second metal may be aluminum, and taking the material of the protective electrode layer 1304 including ITO as an example, the first electrode 131 and the partition structure 132 may be a stacked composite structure of Ti / Al / Ti / ITO.

[0076] Figure 2B The illustrated embodiment takes the stacked composite structure of Ti / Al / Ti / ITO as an example in which the first electrode 131 and the partition structure 132 are. In some examples, the film thickness of the bottom layer Ti in the first electrode 131 and the partition structure 132 is the first thickness t1, the film thickness of Al is the second thickness t2, and the film thickness of the top layer Ti is the third thickness t3. The bottom layer Ti is closer to the base substrate 100 than the top layer Ti. For example, the second thickness t2 may be greater than the third thickness t3, and the first thickness t1 and the third thickness t3 may be the same, so that the side of the partition structure 132 forms an undercut structure.

[0077] For example, the first thickness t1 and the third thickness t3 may be between 300 angstroms and 1000 angstroms, such as 300 angstroms, 500 angstroms, 800 angstroms or 1000 angstroms. The second thickness t2 may be between 500 angstroms and 3000 angstroms, such as 500 angstroms, 1000 angstroms, 1500 angstroms or 2000 angstroms. The thickness t4 of the ITO layer may be between 100 angstroms and 1000 angstroms, such as 100 angstroms, 200 angstroms, 500 angstroms, 800 angstroms or 1000 angstroms. This is conducive to ensuring the characteristics of the first electrode 131 while forming an undercut structure on the side of the partition structure 132.

[0078] The first pixel defining layer 141 has a plurality of first openings K1 and a plurality of second openings K2. The first openings K1 and the second openings K2 are arranged at intervals. The plurality of first openings K1 are used to define the light-emitting area of ​​the light-emitting device. For example, each first opening K1 can expose at least a portion of the first electrode 131 of a light-emitting device, thereby defining the light-emitting area of ​​a light-emitting device. The partition structure 132 is projected on the base substrate 100 within the range of the second opening K2 projected on the base substrate 100.

[0079] In some embodiments, the material of the first pixel defining layer 141 may include an organic material. In this way, the first pixel defining layer 141 can be prepared by a material photolithography process, and the intermediate metal layer (such as aluminum) of the partition structure pattern can be further etched during development, thereby forming an undercut structure on the side of the partition structure 132, which is conducive to simplifying the process. In addition, compared with the inorganic pixel defining layer, the organic pixel defining layer has better bending performance and is more suitable for flexible product design.

[0080] For example, the first electrode 131 and the laminated metal pattern corresponding to the isolation structure (such as a laminated structure pattern of Ti / Al / Ti) can be formed by the same patterning process and etching process, and an electrode protection layer can be formed on the laminated metal pattern. The electrode protection layer wraps around the side of the laminated metal pattern corresponding to the first electrode 131, and is flush with the edge of the laminated metal pattern corresponding to the isolation structure, that is, the side of the laminated metal pattern corresponding to the isolation structure is exposed. Then, an organic material layer is coated on the electrode protection layer, and then the organic material layer is exposed and developed using a mask to form a first pixel defining layer 141. During development, a portion of Al can be etched from the side of the laminated metal pattern corresponding to the isolation structure, so that the middle Al layer is retracted relative to the top layer Ti and the edge of the electrode protection layer, that is, an undercut structure is formed.

[0081] In some embodiments, the side surface of the first pixel defining layer 141 close to the second opening K2 is tilted relative to the direction perpendicular to the base substrate 100, and the distance from the top of the side surface to the center of the second opening K2 is greater than the distance from the bottom of the side surface to the center of the second opening K2. In some examples, the slope angle α of the side surface of the first pixel defining layer 141 close to the second opening K2 can be 20° to 30°, for example, 20°, 25° or 30°, etc., determined according to the needs of the actual product and process conditions, and the present disclosure will not list them one by one. This is conducive to reducing the risk of the second electrode being punctured due to the increase in the thickness of the first electrode 131, and reducing the phenomenon of cracks (Crack) appearing at the overlap of the first pixel defining layer 141 and the first electrode 131.

[0082] like Figure 2A As shown, the first pixel defining layer 141 fills part of the spacing area between the first electrode 131 and the partition structure 132, which helps to prevent the first electrode 131 and the partition structure 132 from being too close and short-circuited. The side of the first pixel defining layer 141 close to the second opening K2 is opposite to the side of the partition structure 132, and a gap is provided between the side of the partition structure 132, so that at least one sub-functional layer in the light-emitting functional layer 150 can be formed from the gap to the side of the partition structure 132, thereby being disconnected at the undercut structure on the side. Figure 2E As shown, the partition structure 132 can effectively partition the charge generation layer (CGL) with higher charge mobility in the light-emitting functional layer 150 without partitioning the second electrode layer 160 .

[0083] Figure 3 A plan view of a partition structure 132 according to some embodiments of the present disclosure is shown. Figure 2A For along Figure 3 It should be noted that, Figure 3This is only an example of the partition structure 132 provided in some embodiments of the present disclosure. The partition structure 132 may also adopt other suitable plane layout designs.

[0084] like Figure 3 As shown, the above-mentioned multiple sub-pixels include a first color sub-pixel p1, a second color sub-pixel p2, and a third color sub-pixel p3. The first color sub-pixel p1 includes a first light-emitting device capable of emitting light of a first color, the second color sub-pixel p2 includes a second light-emitting device capable of emitting light of a second color, and the third color sub-pixel p3 includes a third light-emitting device capable of emitting light of a third color. For example, the first color is red, the second color is green, and the third color is blue. Of course, the embodiments of the present disclosure include but are not limited to this. It should be noted that, Figure 3 The shapes and sizes of the first color sub-pixel p1, the second color sub-pixel p2, and the third color sub-pixel p3 shown in the figure are for illustration only. The layout design can be made according to actual needs, and the present disclosure does not impose any limitation on this.

[0085] The partition structure 132 includes a plurality of annular partition substructures, and each annular partition substructure may be disposed around one or more of the first light emitting device, the second light emitting device, and the third light emitting device. Figure 3 In the illustrated embodiment, each annular partitioning substructure is respectively arranged around the first light-emitting device, the second light-emitting device, and the third light-emitting device, which is conducive to better intercepting the carriers transmitted laterally between adjacent light-emitting devices. For example, the partitioning structure 132 can be a grid structure, and the orthographic projection of the grid line on the base substrate 100 is located in the interval area of ​​each light-emitting device, and the light-emitting area of ​​each light-emitting device is exposed at the mesh of the grid structure.

[0086] In other embodiments, the annular partition substructure surrounding one or more of the first light-emitting device, the second light-emitting device, and the third light-emitting device may be provided with a gap to further ensure that the second electrode layer will not be disconnected, thereby facilitating the transmission of the second electrode signal such as the cathode signal. It should be noted that although the annular partition substructure is provided with the above-mentioned gap, due to the relatively small size of the gap, the resistance of the sub-functional layer (such as the charge generation layer) with a higher charge mobility in the light-emitting functional layer 150 at the position of the gap can be greatly increased, thereby effectively hindering the passage of carriers in the lateral transmission, thereby effectively avoiding crosstalk between adjacent sub-pixels. In addition, since the conductivity of the second electrode layer is greater than the conductivity of each sub-functional layer included in the light-emitting functional layer 150, and multiple light-emitting devices share the second electrode layer, there are multiple conductive channels, so even if the size of the gap is relatively small, it will not hinder the signal transmission on the second electrode layer.

[0087] In some embodiments, the display substrate 10 further includes a driving circuit layer, which is located between the base substrate 100 and the first electrode layer 130 and is configured to form at least a pixel driving circuit for each sub-pixel. For example, the pixel driving circuit may include a plurality of electronic components such as transistors and capacitors. For example, each pixel driving circuit may include three transistors and one capacitor, forming a 3T1C (i.e., one driving transistor, two switching transistors and one capacitor). It may also include more than three transistors and at least one capacitor, such as a 4T1C (i.e., one driving transistor, three switching transistors and one capacitor), a 5T1C (i.e., one driving transistor, four switching transistors and one capacitor) or a 7T1C (i.e., one driving transistor, six switching transistors and one capacitor), etc. Among them, the transistor may be a thin film transistor (Thin Film Transistor, referred to as TFT), a field effect transistor (metal oxide semiconductor, referred to as MOS) or other switching devices with the same characteristics.

[0088] It can be understood that the transistor may include a control electrode, a first electrode, and a second electrode. The control electrode is the gate of the transistor, the first electrode is one of the source and drain of the transistor, and the second electrode is the other of the source and drain of the transistor. Since in some exemplary embodiments, the source and drain of the transistor may be symmetrical in structure, the source and drain thereof may be structurally indistinguishable, so the source of the transistor is referred to as the first electrode, and may also be referred to as the second electrode.

[0089] In some embodiments, each transistor in the pixel driving circuit may be an N-type transistor and / or a P-type transistor, for example, they may all be P-type low temperature polysilicon transistors. At this time, the driving circuit layer may include an active layer, a first gate metal layer, a second gate metal layer, a source-drain metal layer, and a film layer located between these functional film layers and serving as an insulation. The material of the active layer includes low temperature polysilicon. The corresponding routing of the pixel driving circuit can be completed through the first gate metal layer, the second gate metal layer, and the source-drain metal layer.

[0090] In other embodiments, some transistors of the pixel driving circuit are P-type low-temperature polysilicon transistors, and some transistors are N-type oxide transistors. In this case, the driving circuit layer includes two active layers, one of which is a low-temperature polysilicon active layer to form a channel of the P-type low-temperature polysilicon transistor, and the other is an oxide active layer to form a channel of the N-type oxide transistor. In addition, in addition to the first gate metal layer and the second gate metal layer, the driving circuit layer usually also needs to include a third gate metal layer, through which the gate drive signal line and related wiring of the oxide transistor are arranged.

[0091] For example, in Figure 2A and 2BIn the illustrated embodiment, the driving circuit layer may include: a first source-drain metal layer 102, a first active layer ACT1, a first gate metal layer 108, a second gate metal layer 110, a second active layer ACT2, a third gate metal layer 114, a second source-drain metal layer 116, and a third source-drain metal layer 118, which are sequentially stacked on the base substrate 100. For example, the driving circuit layer may also include: a connecting metal layer 112, the connecting metal layer 112 includes a connecting block to realize the electrical connection of the electronic components included in the pixel driving circuit. For example, it can be Figure 2A The connection block in the embodiment realizes the electrical connection between the P-type low temperature polysilicon transistor and the N-type oxide transistor.

[0092] Of course, in addition to the above-mentioned functional film layers, the driving circuit layer also includes an insulating film layer arranged between these functional film layers. Figure 2A As shown, the driving circuit layer may also include a first gate dielectric layer 105 located between the first active layer ACT1 and the first gate metal layer 108, a second gate dielectric layer 107 located between the first gate metal layer 108 and the second gate metal layer 110, a first interlayer insulating layer 109 and a second buffer layer 111 located between the second gate metal layer 110 and the second active layer ACT2, a third gate dielectric layer 113 located between the second active layer ACT2 and the third gate metal layer 114, a second interlayer insulating layer 115 located between the third gate metal layer 114 and the second source-drain metal layer 116, and a first passivation layer 117 located between the second source-drain metal layer 116 and the third source-drain metal layer 118.

[0093] like Figure 2A As shown, the display substrate 10 may further include: a planar layer 120, located between the driving circuit layer and the first electrode layer 130, which plays a planarizing role and is conducive to ensuring the planarity of the first electrode 131. For example, the material of the planar layer 120 may be an organic material, such as a combination of any one or more of resin, acrylic, polyethylene terephthalate, polyimide, polyamide, polycarbonate, epoxy resin, etc.

[0094] like Figure 2A As shown, the display substrate 10 may further include: a second passivation layer 121, located between the planar layer 120 and the first electrode layer 130, which plays a role in preventing over-etching and blocking water vapor from corroding the metal film layer below.

[0095] like Figure 2A As shown, the display substrate 10 may further include a light shield (LS) 104. The light shield 104 may be disposed below the channel of the low-temperature polysilicon transistor to reduce the effect of light on transistor performance. In some examples, the light shield 104 may be made of a metal material, and some signal switching may be achieved through the light shield 104.

[0096] like Figure 2A As shown, the display substrate 10 may further include a barrier layer 101 and a first buffer layer (buffer1) 103. The first source-drain metal layer 102 is disposed on one side of the base substrate 100, the barrier layer 101 is located on the side of the first source-drain metal layer 102 away from the base substrate 100, the light shielding layer 104 is located on the side of the barrier layer 101 away from the first source-drain metal layer 102, and the first buffer layer 103 is located between the light shielding layer 104 and the first active layer ACT1.

[0097] Figure 4A Schematic diagrams showing the structure of the display substrate 10 in some other embodiments of the present disclosure are shown. Figure 4B Shows Figure 4A A magnified view of area A2 in Figure 2. Figure 4A and Figure 4B In some other embodiments of the present disclosure, the surface of the first electrode layer 130 close to the base substrate 100 can be in contact with the flat layer 120 located between the driving circuit layer and the first electrode layer 130, that is, there is no need to set the above-mentioned second passivation layer 121 between the first electrode layer 130 and the flat layer 120.

[0098] like Figure 4A and Figure 4B As shown, the flat layer 120 may include: a main body 1201 and a first support portion 1202 disposed on a side of the main body 1201 away from the substrate 100. A step structure is formed between the first support portion 1202 and the main body 1201, that is, the first support portion 1202 is a convex structure compared to at least a portion of the main body 1201 area to which it is connected. For example, the main body 1201 and the first support portion 1202 may be an integrated structure.

[0099] The first partition portion 201 is located on a side of the first support portion 1202 facing away from the base substrate 100, and the orthographic projection of the first partition portion 201 on the base substrate 100 at least partially overlaps with the orthographic projection of the first support portion 1202 on the base substrate 100. For example, the surface of the first partition portion 201 close to the base substrate 100 may contact the surface of the first support portion 1202 facing away from the base substrate 100.

[0100] The first partition portion 201 has a second protrusion that exceeds the first support portion 1202 in the direction toward the adjacent light-emitting device. A gap 1204 is formed between the second protrusion and the main body 1201 in the direction perpendicular to the base substrate 100. That is, on the basis that the second partition portion 202 is retracted compared to the third partition portion 203, the flat layer 120 is concave compared to the first partition portion 201, so that the side of the partition structure 132 facing the adjacent light-emitting device has a double undercut structure, which is beneficial to improving the partition effect of the partition structure 132.

[0101] For example, the orthographic projection of the first supporting portion 1202 on the base substrate 100 is located within the orthographic projection range of the surface of the first partition portion 201 on the side close to the base substrate 100 on the base substrate 100 .

[0102] For example, in order to achieve a better partition effect, the step height of the above-mentioned step structure, that is, the gap distance between the second protrusion and the main body 1201 in the direction perpendicular to the base substrate 100 can be 0.2 microns to 0.5 microns, such as 0.2 microns, 0.3 microns, 0.4 microns or 0.5 microns, etc., which can be determined according to the actual product needs and process conditions, and the present disclosure will not list them one by one.

[0103] There are many ways to form an undercut structure between the first partition portion 201 and the flat layer 120. Three methods are mainly listed below for illustration. In actual implementation, other applicable methods may also be used, and the present disclosure does not limit this. The first method: When etching the first electrode pattern and the isolation structure pattern using a dry etching process, a portion of the flat layer 120 can be etched away by controlling the etching parameters during the dry etching of the first electrode pattern and the isolation structure pattern, thereby forming an undercut structure between the first partition portion 201 and the flat layer 120 and between the first electrode 131 and the flat layer 120. The second method is to etch the flat layer 120 again after completing the pattern etching of the first electrode layer 130, thereby forming an undercut structure between the first partition portion 201 and the flat layer 120 and between the first electrode 131 and the flat layer 120. The third method is to, after completing the pattern etching of the first electrode layer 130, separately etch away part of the flat layer 120 around the first partition portion 201 of the partition structure 132, that is, to form a groove on the flat layer 120, so that the flat layer 120 is concave compared to the edge of the first partition portion 201, thereby forming an undercut structure only between the first partition portion 201 of the partition structure 132 and the flat layer 120.

[0104] It should be noted that when the first or second method mentioned above is adopted, a portion of the flat layer 120 area not covered by the first electrode pattern and the isolation structure pattern will be etched away, and an undercut structure will be formed between the first partition portion 201 and the flat layer 120 and between the first electrode 131 and the flat layer 120.

[0105] At this time, in addition to the first supporting portion 1202, the flat layer 120 may further include: a second supporting portion 1203 disposed on a side of the main body 1201 away from the base substrate 100, such as Figure 4A As shown. The second support portion 1203 and the first support portion 1202 are arranged at intervals. The first support portion 1202 and the second support portion 1203 exceed the main body portion 1201 in a direction perpendicular to the base substrate 100, and form a step structure with the main body portion 1201. For example, the surface of the first support portion 1202 facing away from the base substrate 100 is the first surface, the surface of the second support portion 1203 facing away from the base substrate 100 is the second surface, and the surface of the main body 1201 facing away from the base substrate 100 is the third surface. The distance between the first surface and the second surface and the base substrate 100 is greater than the distance between the third surface and the base substrate 100, that is, there is a step between the first surface and the second surface and the third surface.

[0106] The first electrode 131 is located on a side of the second support portion 1203 facing away from the base substrate 100, and the orthographic projection of the first electrode 131 on the base substrate 100 at least partially overlaps with the orthographic projection of the second support portion 1203 on the base substrate 100. For example, the surface of the first electrode 131 close to the base substrate 100 may be in contact with the second support portion 1203. For example, the orthographic projection of the second support portion 1203 on the base substrate 100 may be located within the range of the orthographic projection of the first electrode 131 on the base substrate 100.

[0107] In some embodiments, the first electrode 131 also has a third protrusion extending beyond the second support portion 1203 in a direction toward the adjacent partition structure 132. It should be noted that the gap formed by the presence of the third protrusion can be filled by the organic first pixel defining layer 141 that subsequently covers the first electrode layer 130 to ensure the flatness of the first electrode 131, thereby avoiding affecting the light-emitting performance of the light-emitting device.

[0108] In the case of adopting the third method, only a portion of the planar layer 120 area corresponding to the edge of the isolation structure pattern will be etched away, thereby forming an undercut structure between the first partition portion 201 and the planar layer 120. For example, Figure 5A Schematic diagrams showing the structure of the display substrate 10 in some other embodiments of the present disclosure are shown. Figure 5B Shows Figure 5A A magnified view of the A3 area. Figure 5A and 5B As shown, a groove 300 is provided on the surface of the flat layer 120 on the side away from the base substrate 100, and the groove 300 is located at a position directly opposite to the side of the isolation structure. The first support portion 1202 is located between the grooves 300 on both sides of the isolation structure, and is used to support the isolation structure. The orthographic projection of the edge of the first partition portion 201 on the base substrate 100 is located within the orthographic projection range of the groove 300 on the base substrate 100, so that the first partition portion 201 has a second protrusion that exceeds the first support portion 1202 in the direction toward the adjacent light-emitting device.

[0109] By providing the above-mentioned groove 300, a gap can be provided between the second protrusion and the main body 1201 in a direction perpendicular to the base substrate 100, that is, a gap between the side of the second protrusion close to the base substrate 100 and the bottom surface of the groove 300. In other words, the depth of the groove 300 in a direction perpendicular to the base substrate 100 is the gap distance between the second protrusion and the main body 1201.

[0110] For example, the groove 300 has a first side surface and a second side surface that are oppositely disposed, the first side surface is covered by the partition structure 132, and the second side surface is not covered by the partition structure 132. In other words, the orthographic projection of the first side surface on the base substrate 100 is located within the orthographic projection of the partition structure 132 on the base substrate 100, and the orthographic projection of the second side surface on the base substrate 100 is located outside the orthographic projection of the partition structure 132 on the base substrate 100.

[0111] For example, the bottom end of the side surface of the first pixel defining layer 141 close to the second opening K2 may be flush with the second side surface. For example, the orthographic projection of the groove 300 of the flat layer 120 on the base substrate 100 may be located within the orthographic projection range of the lower port of the second opening K2 on the base substrate 100. The lower port is an opening relatively closer to the base substrate 100, and the area of ​​the lower port is smaller than the area of ​​the upper port.

[0112] In some embodiments, the display substrate 10 may further include: a first power signal line VSS and a second power signal line VDD (not shown in the figure), which are located on the side of the first electrode layer 130 close to the base substrate 100. The first power voltage transmitted by the first power signal line is less than the second power voltage transmitted by the second power signal line. The partition structure 132 has a conductive property, and the partition structure 132 is electrically connected to the first power signal line. In this way, in addition to the physical isolation function of the partition structure 132 itself, the conductive partition structure 132 can be electrically connected to the first power signal line VSS to keep the partition structure 132 in a low voltage state, thereby playing a role in conducting away the lateral carriers remaining in the light-emitting functional layer 150, which is equivalent to achieving physical isolation through the undercut structure of the partition structure 132 itself, while also achieving electrical isolation, which is conducive to further reducing the crosstalk between adjacent sub-pixels.

[0113] For example, the display substrate 10 further includes: a metal wiring layer provided with the first power signal line VSS, which is located on the side of the first electrode layer 130 close to the base substrate 100. The display substrate 10 further includes a passivation layer located on the side of the metal wiring layer close to the first electrode layer 130. The passivation layer can protect the metal wiring layer from corrosion. The partition structure 132 can be electrically connected to the first power signal line VSS through a via penetrating the passivation layer.

[0114] Fig. 6A Schematic diagrams showing the structure of the display substrate 10 of some other embodiments of the present disclosure are shown. Figure 6B Shows Fig. 6A A magnified view of the A4 area. Fig. 6A and Figure 6B ,exist Figure 2A and Figure 2B On the basis of the corresponding embodiment, the metal wiring layer provided with the first power signal line VSS may be the second source-drain metal layer 116, and the passivation layer located on the side of the metal wiring layer close to the first electrode layer 130 may include the first passivation layer 117 and the second passivation layer 121. The partition structure 132 may be electrically connected to the first power signal line VSS located in the second source-drain metal layer 116 through a via hole that sequentially penetrates the second passivation layer 121, the planar layer 120, and the first passivation layer 117.

[0115] Fig. 7A Schematic diagrams showing the structure of the display substrate 10 of some other embodiments of the present disclosure are shown. Figure 7B Shows Fig. 7A Magnified view of area A5 in the middle. Fig. 7A and Figure 7B ,exist Figure 4A and Figure 4BOn the basis of the corresponding embodiment, the metal wiring layer provided with the first power signal line VSS may be the second source-drain metal layer 116, and the passivation layer located on the side of the metal wiring layer close to the first electrode layer 130 may include the first passivation layer 117. The partition structure 132 may be electrically connected to the first power signal line VSS located in the second source-drain metal layer 116 through a via hole that sequentially penetrates the flat layer 120 and the first passivation layer 117.

[0116] In some embodiments, the display substrate 10 may further include: a second pixel defining layer 142, which is located on the side of the first pixel defining layer 141 close to the base substrate 100. The orthographic projection of the partition structure 132 on the base substrate 100 is located within the orthographic projection range of the second pixel defining layer 142 on the base substrate 100. The material of the second pixel defining layer 142 includes: an inorganic insulating material, such as silicon nitride or silicon oxide. The second pixel defining layer 142 conformally covers the partition structure 132, that is, wraps the side of the partition structure 132 and the surface on the side away from the base substrate 100, which can play an insulating and protective role, thereby further enhancing the partition structure 132 The effect of isolating carriers transmitted laterally.

[0117] The second pixel defining layer 142 is stacked with the first pixel defining layer 141, and in addition to playing an insulating role between the partition structure 132 and the light-emitting functional layer 150, it also needs to cooperate with the first pixel defining layer 141 to define the light-emitting area of ​​the light-emitting device. The second pixel defining layer 142 has a plurality of third openings K3, and the orthographic projections of the third openings K3 on the base substrate 100 at least partially overlap with the orthographic projections of the first openings K1 on the base substrate 100 to expose at least a portion of the first electrode 131.

[0118] Fig. 8A Schematic diagrams showing the structure of the display substrate 10 of some other embodiments of the present disclosure are shown. Figure 8B Shows Fig. 8A Enlarged view of the middle A6 region; Fig.9A Schematic diagrams showing the structure of the display substrate 10 of some other embodiments of the present disclosure are shown. Fig. 9B Shows Fig.9A Magnified view of region A7 in Figure 2. Fig. 8A and Figure 8B ,exist Figure 2A and Figure 2B On the basis of the corresponding embodiment, the display substrate 10 further includes the above-mentioned second pixel defining layer 142. At the second opening K2 of the first pixel defining layer 141, the first pixel defining layer 141 conformally covers the side surface of the first isolation portion and the surface not covered by the second isolation portion, the side surface of the second isolation portion, and the side surface and surface (including the upper and lower surfaces) of the third isolation portion that are not in contact with the second isolation portion.

[0119] In order to ensure the partitioning effect of the partitioning structure 132 on at least one sub-functional layer in the light-emitting functional layer 150, it is necessary to reasonably design the thickness of the second pixel defining layer 142. For example, in the direction perpendicular to the base substrate 100, the thickness of the second pixel defining layer 142 is less than half of the thickness of the second partitioning portion 202, and less than the width of the first protrusion in the direction toward the adjacent light-emitting device, so that on the basis of the side of the partitioning structure 132 conformingly covering the second pixel defining layer 142, an undercut structure capable of partitioning at least one sub-functional layer in the light-emitting functional layer 150 is still retained.

[0120] See also Fig.9A and Fig. 9B ,exist Figure 4A and Figure 4B On the basis of the corresponding embodiment, the display substrate 10 further includes the above-mentioned second pixel defining layer 142. At the second opening K2 of the first pixel defining layer 141, the second pixel defining layer 142 conformally covers the main body 1201 exposed from the second opening K2, the side of the first supporting portion 1202, the surface of the first isolation portion that is not in contact with the first supporting portion 1202 and the second isolation portion, the side of the second isolation portion, and the side and surface (including the upper and lower surfaces) of the third isolation portion that are not in contact with the second isolation portion.

[0121] For example, in order to ensure that the double undercut structure formed on the side of the partition structure 132 can still play a role in isolating at least one sub-functional layer in the light-emitting functional layer 150, the thickness of the second pixel defining layer 142 is also smaller than the width of the second protrusion in the direction toward the adjacent light-emitting device, and smaller than half of the gap distance between the second protrusion and the main body 1201.

[0122] Fig. 10A Schematic diagrams showing the structure of the display substrate 10 of some other embodiments of the present disclosure are shown. Fig. 10B Shows Fig. 10A Enlarged view of the middle A8 region; Fig.11A Schematic diagrams showing the structure of the display substrate 10 of some other embodiments of the present disclosure are shown. Fig. 11B Shows Fig.11A A magnified view of the A9 region in the middle. Fig. 10A and Fig. 10B ,exist Fig. 6A and Figure 6B Based on the embodiment shown, the display substrate 10 further includes the second pixel defining layer 142 to further enhance the partitioning effect of the partition structure 132. The specific structure of the second pixel defining layer 142 can be seen in Fig. 8A and Figure 8B The relevant description of the corresponding embodiment will not be repeated here. Fig.11A and Fig. 11B ,exist Fig. 7A and Figure 7B Based on the embodiment shown, the display substrate 10 further includes the second pixel defining layer 142 to further enhance the partitioning effect of the partition structure 132. The specific structure of the second pixel defining layer 142 can be seen in Fig.9A and Fig. 9B The relevant description of the corresponding embodiments will not be repeated here.

[0123] Fig.12 Schematic diagram of the structure of the display substrate 10 of some embodiments of the present disclosure is shown. Fig.12 The light emitting function layer 150 covers the first pixel defining layer 141 , the first electrode 131 exposed from the first opening K1 of the first pixel defining layer 141 , and the partition structure 132 exposed from the second opening K2 .

[0124] For example, the multiple sub-functional layers of the light-emitting functional layer 150 may include: a charge generation layer 152 and a first light-emitting layer 151 and a second light-emitting layer 153 stacked on both sides of the charge generation layer 152. The charge generation layer 152 is disconnected at the location where the partition structure 132 is located. It should be noted that the charge generation layer 152 in the light-emitting functional layer 150 is a discontinuous structure or a non-integrated structure at the disconnected location.

[0125] For example, the first light emitting layer 151 is located on a side of the charge generation layer 152 close to the base substrate 100 , and the second light emitting layer 153 is located on a side of the charge generation layer 152 away from the base substrate 100 .

[0126] It should be noted that the light-emitting functional layer 150 may also include other sub-functional layers (not shown in the figure) in addition to the charge generation layer 152, the first light-emitting layer 151 and the second light-emitting layer 153, such as a hole injection layer, a hole transport layer, an electron injection layer and an electron transport layer.

[0127] like Fig.12 As shown, the second electrode layer 160 is located on the side of the light-emitting functional layer 150 away from the base substrate 100. The second electrode layer 160 includes a second electrode for each light-emitting device. For example, the second electrodes of adjacent light-emitting devices can be connected together to facilitate applying a signal to the second electrode. One of the first electrode 131 and the second electrode serves as an anode of the light-emitting device, and the other serves as a cathode. For example, the first electrode 131 is an anode of the light-emitting device, and the second electrode is a cathode of the light-emitting device.

[0128] For example, the second electrode can be made of any one or more of magnesium (Mg), silver (Ag), and aluminum (Al), or an alloy made of any one or more of the above metals, or a transparent conductive material such as ITO, or a multilayer composite structure of metal and transparent conductive material.

[0129] In some embodiments, the display substrate 10 may further include a capping layer (CPL), which is located on a side of the second electrode layer 160 away from the base substrate 100 , and is beneficial to improving the light extraction efficiency of the light emitting device.

[0130] In some embodiments, the display substrate 10 may further include an encapsulation layer 170, which is located on a side of the capping layer away from the base substrate 100. Fig.12 The encapsulation layer 170 is used to encapsulate the light emitting device and prevent water and oxygen from corroding and damaging the device.

[0131] For example, the encapsulation layer 170 may include a first encapsulation layer, a second encapsulation layer, and a third encapsulation layer stacked in sequence. The first encapsulation layer and the third encapsulation layer may be inorganic encapsulation layers, for example, inorganic materials such as nitrides, oxides, oxynitrides, nitrates, carbides, or any combination thereof may be used, and the preparation process may be a chemical vapor deposition (CVD) process. The second encapsulation layer may be an organic encapsulation layer, for example, organic materials such as acrylic, hexamethyldisiloxane, polyacrylates, polycarbonates, polystyrene, etc. may be used, and the preparation process may be an inkjet printing (IJP) process.

[0132] Fig.13 FIG. 1 is a flow chart showing a method for preparing a display substrate 10 according to some embodiments of the present disclosure. The method is used to prepare the display substrate 10 provided in the above embodiments. Fig.13 As shown, the preparation method may include the following steps:

[0133] Step S101, providing a backplane, the backplane comprising a base substrate and a driving circuit layer disposed on the base substrate;

[0134] Step S102, forming a first electrode layer on the backplane, the first electrode layer comprising: a first electrode of each light-emitting device and a partition structure spaced apart from the first electrode, the partition structure being located between two adjacent light-emitting devices, comprising a first partition portion, a second partition portion and a third partition portion stacked in a direction perpendicular to the base substrate, the third partition portion having a first protrusion extending beyond the second partition portion in a direction toward the adjacent light-emitting device;

[0135] Step S103, forming a first pixel defining layer on the first electrode layer, wherein the first pixel defining layer has a plurality of first openings and a plurality of second openings, wherein the first openings expose at least a portion of the first electrode, and the orthographic projection of the partition structure on the base substrate is located within the orthographic projection range of the second openings on the base substrate;

[0136] Step S104, forming a light-emitting functional layer on the first pixel defining layer, the light-emitting functional layer comprising: a plurality of sub-functional layers, at least one of the plurality of sub-functional layers being disconnected at a position where the partition structure is located;

[0137] Step S105, forming a second electrode layer on the light-emitting functional layer.

[0138] Fig.14 A partial process flow chart of display substrates according to some embodiments of the present disclosure is shown. Fig.14 For the above step S102, an electrode material layer 400 may be formed on the back plate first. Fig.14 As shown in FIG. 4( a), the electrode material layer 400 may include a first Ti layer 401, an Al layer 402, and a second Ti layer 403 stacked in sequence, that is, a Ti / Al / Ti composite material layer. Then, the electrode material layer 400 is etched to form a partition structure pattern 420 and a first electrode pattern 410, as shown in FIG. Fig.14 As shown in (b) of FIG. 4 , the partition structure pattern 420 includes: a first partition layer 421, a second partition layer 422, and a third partition layer 433 which are stacked in sequence. At this time, the partition structure pattern 420 and the first electrode pattern 410 are both a stacked structure of Ti / Al / Ti, the material of the first partition layer and the third partition layer is Ti, and the material of the second partition layer is Al.

[0139] In some embodiments, the backplane provided in step S101 further includes: a flat layer located on the side of the driving circuit layer away from the base substrate, so as to ensure the flatness of the first electrode as much as possible. Figure 4B or Figure 5BIn the corresponding embodiment, the partition structure has a double undercut structure, thereby improving the partition effect. In the above step S102, an electrode material layer 400 can be formed on the flat layer 120, that is, the electrode material layer 400 is in contact with the flat layer 120. In addition, in addition to etching the electrode material layer 400 to form the partition structure pattern 420 and the first electrode pattern 410, it is also necessary to etch part of the flat layer 120 to form a first support portion 1202 on the flat layer 120, and the first partition layer 421 has a second protrusion that exceeds the first support portion 1202 in the direction toward the adjacent light-emitting device, and the second protrusion has a gap with the flat layer 120 in the direction perpendicular to the substrate. It should be noted that the first partition layer 421 is the first partition portion 201 of the partition structure 132 finally formed, and an undercut structure is formed between it and the etched flat layer 120. Fig.15A FIG. 1 shows a micrograph of an undercut structure formed between the first partition portion 201 and the planar layer 120 .

[0140] There are many ways to etch a portion of the flat layer. In some embodiments, when the electrode material layer 400 is a metal material stack of Ti / Al / Ti, the electrode material layer 400 can be etched by a dry etching process to form a partition structure pattern 420 and a first electrode pattern 410, and in this process, the flat layer 120 below is overetched to form a first support portion 1202 and a second support portion 1203, such as Fig.14 As shown in FIG. (b) in FIG. Of course, in other embodiments, after obtaining the partition structure pattern 420 and the first electrode pattern 410, a portion of the flat layer 120 may be etched separately to form the first support portion 1202 on at least the flat layer 120 to obtain a partition structure with a double undercut structure. In actual implementation, it can be determined according to the needs of the actual product and the process conditions, and the present disclosure does not limit this.

[0141] Furthermore, in order to protect the first electrode pattern 410, a protective material layer such as an ITO film may be formed on the partition structure pattern 420 and the first electrode pattern 410. Then, the protective material layer is etched to retain the side surface of the first electrode pattern 410 and the protective material on the side surface away from the substrate, and the protective material on the side surface of the partition structure pattern 420 away from the substrate, and remove the protective material at other positions (including the side surface of the partition structure pattern 420) to form a protective electrode layer 1304, such as Fig.14 Next, part of the second partition layer 422 in the partition structure pattern 420 can be removed, thereby forming a partition structure 132 having the first partition portion 201, the second partition portion 202 and the third partition portion 203.

[0142] Furthermore, a first pixel defining layer is formed. In some embodiments, in order to simplify the process, the first pixel defining layer 141 may be made of an organic material, so that while the first pixel defining layer 140 is being developed, part of the second partition layer 422 may be removed to obtain the second partition portion 202 of the partition structure 132 that is finally formed. At this time, the above-mentioned process of forming the first pixel defining layer on the first electrode layer may include: forming an organic material layer on the first electrode layer; forming a plurality of first openings K1 and a plurality of second openings K2 by photolithography and development of the organic material layer, that is, forming the first pixel defining layer 141; and, in the process of developing the organic material layer, part of the second partition layer 422 may be removed to form the first protrusion of the partition structure 132, such as Fig.14 As shown in Figure (d). Fig. 15B A micrograph of an ITO / Ti / Al / Ti partition structure formed after etching away part of Al by development is shown.

[0143] in addition, Fig.16 Schematic diagram of the structure of the display device of some embodiments of the present disclosure is shown. Fig.16 As shown, the display device 1000 includes the display substrate 10 provided in any of the above embodiments. Since the display substrate 10 sets a partition structure in the same layer as the first electrode between the light-emitting devices of adjacent sub-pixels, at least one sub-functional layer (such as the charge generation layer) in the light-emitting functional layer is disconnected at the location where the partition structure is located, which is beneficial to reduce the lateral transmission of carriers between adjacent sub-pixels and reduce the crosstalk between adjacent sub-pixels. Therefore, the display device 1000 including the display substrate 10 can also reduce the crosstalk between adjacent sub-pixels, thereby having a higher display quality.

[0144] For example, the display device 1000 may be an augmented reality (AR) device, a virtual reality (VR) device, a wearable device, a display screen, a mobile phone, a laptop computer, a tablet computer, a television, a digital photo frame, or any other electronic product or component with a display function. Of course, the display device 1000 provided in the embodiment of the present disclosure is not limited to the types listed above.

[0145] In the above description, the technical details such as the composition of each layer of the product are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. Although each embodiment is described separately above, it does not mean that the measures in each embodiment cannot be used in combination to advantage.

[0146] It should be noted that the drawings of the embodiments of the present disclosure only relate to the structures related to the embodiments of the present disclosure, and other structures can refer to the general design. In the absence of conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0147] Although some embodiments of the present disclosure have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiment and all changes and modifications falling within the scope of the present disclosure.

Claims

1. A display substrate, characterized in that: include: A base substrate and a light-emitting device layer arranged on the base substrate, wherein the light-emitting device layer includes a first electrode layer, a first pixel defining layer, a light-emitting function layer and a second electrode layer stacked on the base substrate to form a plurality of light-emitting devices, wherein: The first electrode layer includes a first electrode of the light-emitting device and a partition structure spaced apart from the first electrode, the partition structure is located between adjacent light-emitting devices, the partition structure includes a first partition portion, a second partition portion and a third partition portion stacked in a direction perpendicular to the base substrate, the third partition portion has a first protrusion that exceeds the second partition portion in a direction toward the adjacent light-emitting device; The first pixel defining layer has a plurality of first openings and a plurality of second openings, the plurality of first openings are used to define the light emitting area of ​​the light emitting device, and the orthographic projection of the partition structure on the base substrate is located within the orthographic projection range of the second opening on the base substrate; The light-emitting functional layer includes a plurality of sub-functional layers, and at least one of the plurality of sub-functional layers is disconnected at a position where the partition structure is located.

2. The display substrate according to claim 1, characterized in that: Also includes: a driving circuit layer and a planar layer located between the driving circuit layer and the first electrode layer; The flat layer includes: a main body portion and a first supporting portion arranged on a side of the main body portion away from the base substrate, a step structure is formed between the first supporting portion and the main body portion, the first partition portion is located on a side of the first supporting portion away from the base substrate, and the orthographic projection of the first supporting portion on the base substrate at least partially overlaps with the orthographic projection of the first supporting portion on the base substrate, the first partition portion has a second protrusion extending beyond the first supporting portion in a direction toward the adjacent light-emitting device, and the second protrusion has a gap with the main body portion in a direction perpendicular to the base substrate.

3. The display substrate according to claim 2, characterized in that: The planar layer also includes: a second supporting portion arranged on a side of the main body away from the base substrate, the first supporting portion and the second supporting portion extend beyond the main body in a direction perpendicular to the base substrate, the first electrode is located on a side of the second supporting portion away from the base substrate, and its orthographic projection on the base substrate at least partially overlaps with the orthographic projection of the second supporting portion on the base substrate, and the first electrode has a third protrusion extending beyond the second supporting portion in a direction toward the adjacent partition structure.

4. The display substrate according to any one of claims 1 to 3, characterized in that: Also includes: A first power signal line and a second power signal line are located on a side of the first electrode layer close to the base substrate. A first power voltage transmitted by the first power signal line is lower than a second power voltage transmitted by the second power signal line. The partition structure has conductive properties and is electrically connected to the first power signal line.

5. The display substrate according to claim 4, characterized in that: Also includes: A metal wiring layer provided with the first power signal line, located on a side of the first electrode layer close to the base substrate; as well as The passivation layer is located on a side of the metal wiring layer close to the first electrode layer, and the partition structure is electrically connected to the first power signal line through a via hole penetrating the passivation layer.

6. The display substrate according to any one of claims 1 to 3, characterized in that: Also includes: A second pixel defining layer is located on a side of the first pixel defining layer close to the base substrate, and the material of the second pixel defining layer includes: an inorganic insulating material; The second pixel defining layer conformally covers the partition structure, and the orthographic projection of the partition structure on the base substrate is within the orthographic projection range of the second pixel defining layer on the base substrate. The second pixel defining layer has a plurality of third openings, and the orthographic projections of the third openings on the base substrate at least partially overlap with the orthographic projections of the first openings on the base substrate to expose at least a portion of the first electrode; Along a direction perpendicular to the base substrate, a thickness of the second pixel defining layer is less than half of a thickness of the second partition portion, and is less than a width of the first protrusion in a direction toward the adjacent light emitting device.

7. The display substrate according to any one of claims 1 to 3, characterized in that: The material of the first pixel defining layer includes an organic material; The slope angle of the side surface of the first pixel defining layer close to the second opening is 20° to 30°, and the distance from the top of the side surface to the center of the second opening is greater than the distance from the bottom of the side surface to the center of the second opening.

8. The display substrate according to any one of claims 1 to 3, characterized in that: The first electrode is a multi-layer composite structure, and the partition structure includes the same number and material of film layers as the first electrode.

9. The display substrate according to any one of claims 1 to 3, characterized in that: The first electrode and the partition structure respectively include: a stacked metal electrode layer and a protective electrode layer, the metal electrode layer includes at least a stacked first sublayer and a second sublayer, the protective electrode layer is located on a side of the second sublayer away from the first sublayer, the material of the first sublayer includes a first metal, and the material of the second sublayer includes a second metal; The first partition portion in the partition structure includes the first sub-layer, the second partition portion includes the second sub-layer, and the third partition portion includes the protective electrode layer.

10. The display substrate according to claim 9, characterized in that: The metal electrode layer further includes a third sublayer stacked between the second sublayer and the protective electrode layer. The third partition portion further includes the third sublayer. The material of the third sublayer includes the first metal.

11. The display substrate according to claim 9, characterized in that: The protective electrode layer in the first electrode is located on the side of the metal electrode layer away from the base substrate and wraps the side of the metal electrode layer; the protective electrode layer in the partition structure is located on the side of the metal electrode layer away from the base substrate and its edge is flush with the edge of the third partition portion.

12. The display substrate according to any one of claims 1 to 3, characterized in that: The plurality of sub-functional layers include a charge generation layer and a first light-emitting layer and a second light-emitting layer stacked on both sides of the charge generation layer, and the charge generation layer is disconnected at a position where the partition structure is located.

13. A display device, characterized in that: A display substrate comprising any one of claims 1-12.

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