Display substrate, preparation method thereof and display device

Abstract

The invention provides a display substrate, a preparation method thereof and a display device, belongs to the technical field of display, and can solve the problems that an existing display substrate is poor in crosstalk and the preparation process of a partition structure is complex. The display substrate of the present disclosure comprises: a substrate; a first electrode layer including a first electrode of each light emitting device; the pixel defining layer is provided with a plurality of pixel openings; a light-emitting functional layer including a light-emitting functional portion of each light-emitting device; the partition structures are configured to enable at least part of the sub-functional layers in the light-emitting functional layer to be disconnected at the positions corresponding to the edges of the pixel openings; the partition structure comprises a first substructure and a second substructure which are respectively made of a first conductive material and a second conductive material; the second conductive material includes a material obtained by a replacement reaction of the first conductive material and the first solution, and a solute in the first solution includes a compound of ions of the second conductive material. The display substrate is simple in preparation process and has a good anti-crosstalk effect.

Description

Technical Field

[0001] The present disclosure belongs to the field of display technology, and particularly relates to a display substrate and a preparation method thereof, and a display device. Background Art

[0002] Active Matrix Organic Light Emitting Diode (AMOLED) is a new type of display technology with the advantages of self-luminescence, wide color gamut, high contrast and flexible display. For this reason, the application scenarios of AMOLED display technology are expanding. For example, more and more mobile display device manufacturers are more inclined to apply AMOLED display technology to various display devices, especially foldable mobile phones or laptops, in order to improve the performance and competitiveness of their products. It can be foreseen that AMOLED series display devices will become one of the most important display products in the next few years.

[0003] At the same time, there are still some areas that need to be improved in AMOLED display technology. For example, although AMOLED-based display screens have the advantages of high color saturation and wide color gamut, this may also cause colors to be too bright or crosstalk between pixels of different colors, affecting color accuracy. For example, when the AMOLED display screen displays black, the pixel units do not emit light, which can achieve the effect of saving power. However, when displaying white, the energy required is more than that of traditional LCD displays, resulting in AMOLED products requiring greater power consumption.

[0004] Therefore, in order to overcome the limitations of AMOLED display technology in practical applications, it is necessary to improve the existing AMOLED. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. On the one hand, a display substrate is provided, which comprises: a base substrate; a first electrode layer, which is arranged on the base substrate, the first electrode layer comprising a first electrode of each light-emitting device; a pixel defining layer, which is arranged on a side of the first electrode layer away from the base substrate, the pixel defining layer having a plurality of pixel openings penetrating along a thickness direction thereof; a light-emitting function layer, which is arranged on a side of the pixel defining layer away from the base substrate, the light-emitting function layer comprising a light-emitting function portion of each light-emitting device; one of the pixel openings and the first electrode and the light-emitting function portion of one of the light-emitting devices are arranged on the base substrate. The orthographic projections on the bottom substrate at least partially overlap; a plurality of partition structures are arranged on the side of the first electrode layer away from the base substrate, and the partition structures are configured to make at least part of the sub-functional layers in the light-emitting functional layer disconnected at the position corresponding to the edge of the pixel opening; wherein the partition structure includes a first substructure and a second substructure wrapping the first substructure; the materials of the first substructure and the second substructure are a first conductive material and a second conductive material, respectively; the second conductive material includes a material obtained by a replacement reaction between the first conductive material and a first solution, and the solute in the first solution includes a compound of ions of the second conductive material.

[0006] In some examples, the first conductive material includes aluminum, the second conductive material includes silver, and the solute of the first solution includes silver nitrate.

[0007] In some examples, the display substrate further includes a second electrode layer disposed on the side of the light-emitting functional layer away from the base substrate; the second electrode layer includes a second electrode of each of the light-emitting devices, and a first connecting portion connecting adjacent second electrodes; the partition structure includes a notch, and the orthographic projections of one notch and one of the first connecting portions on the base substrate at least partially overlap.

[0008] In some examples, the display substrate also includes a driving circuit layer arranged on the side of the first electrode layer close to the base substrate, and the driving circuit layer includes a plurality of pixel driving circuits; the first electrode includes a first main body portion, and a second connecting portion connected to the first main body portion, and one second connecting portion is electrically connected to one pixel driving circuit; the partition structure and the orthographic projection of the second connecting portion on the base substrate have no overlap.

[0009] In some examples, the partition structure and the corresponding pixel opening have overlapping orthographic projections on the substrate.

[0010] In some examples, the pixel defining layer also has a plurality of auxiliary openings extending through the pixel defining layer along its thickness direction, and one of the auxiliary openings is arranged around one of the pixel openings; the partition structure corresponding to the pixel opening overlaps with the orthographic projection of the auxiliary opening arranged around the pixel opening on the base substrate.

[0011] In some examples, for the partition structure and the corresponding pixel opening, the longitudinal section of the partition structure has a first side and a second side relatively arranged along the thickness direction of the substrate, and a third side and a fourth side connecting the first side and the second side, the third side is closer to the first center line than the fourth side; at least some points on the third side have different distances from the first center line, and the closer the point to the substrate, the longer the distance to the first center line; the first center line is a straight line that passes through the center of the positive projection of the pixel opening on the substrate and extends along the thickness direction of the substrate.

[0012] In some examples, the light-emitting functional layer includes a hole injection layer; the partition structure is disposed on a side of the hole injection layer close to the base substrate, and the partition structure is configured to disconnect the hole injection layer at a position corresponding to the edge of the pixel opening.

[0013] In some examples, the light-emitting functional layer includes a first light-emitting material layer, a second light-emitting material layer, and a charge generating layer located between the first light-emitting material layer and the second light-emitting material layer; the partition structure is arranged on a side of the charge generating layer close to the base substrate, and the partition structure is configured so that the charge generating layer is disconnected at a position corresponding to the edge of the pixel opening.

[0014] In a second aspect, the present invention provides a method for preparing a display substrate, the display substrate being as described in any example of the first aspect above, wherein the preparation method comprises: providing a base substrate; forming a first electrode layer on the base substrate; forming an initial first substructure on a side of the first electrode layer away from the base substrate; the material of the initial first substructure is a first conductive material; patterning the first electrode layer using a first solution to form a first electrode of each light-emitting device; at the same time, using the first solution to undergo a replacement reaction with the initial first substructure to form a partition structure; the partition structure comprises a first substructure and a second substructure wrapping the first substructure, the materials of the first substructure and the second substructure being the first conductive material and the second conductive material, respectively; The second conductive material includes a material obtained by a replacement reaction between the first conductive material and the first solution, and the solute in the first solution includes a compound of the second conductive material ions; a pixel defining layer is formed on the side of the first electrode layer away from the base substrate, and a plurality of pixel openings penetrating along the thickness direction of the pixel defining layer are formed; a light-emitting functional layer is formed on the side of the pixel defining layer away from the base substrate; the light-emitting functional layer includes the light-emitting functional parts of each of the light-emitting devices, and the positive projections of one pixel opening and the first electrode and the light-emitting functional part of one of the light-emitting devices on the base substrate at least partially overlap; and at least part of the sub-functional layers in the light-emitting functional layer are disconnected at the position corresponding to the edge of the pixel opening.

[0015] In some examples, an initial first substructure is formed on a side of the first electrode layer facing away from the substrate, including: forming a first conductive material layer on a side of the first electrode layer facing away from the substrate; composing the first conductive material layer to form the initial first substructure; the initial first substructure is arranged around a pixel opening; for the initial first substructure and the corresponding pixel opening, a longitudinal section of the initial first substructure has a first bottom edge and a second bottom edge relatively arranged along the thickness of the substrate, and a third side edge and a fourth side edge connecting the first bottom edge and the second bottom edge; the third side edge is closer to the first center line than the fourth side edge; at least some points on the third side edge have different distances from the first center, and the closer the point to the substrate, the shorter the distance to the first center line; the first center line is a straight line that passes through the center of the positive projection of the pixel opening on the substrate and extends along the thickness direction of the substrate.

[0016] In some examples, while forming a plurality of pixel openings extending through the pixel defining layer in a thickness direction, the method further includes: forming a plurality of auxiliary openings extending through the pixel defining layer in a thickness direction; one of the auxiliary openings being arranged around one of the pixel openings; and the partition structure arranged corresponding to the pixel opening overlapping with the orthographic projection of the auxiliary opening arranged around the pixel opening on the substrate.

[0017] In some examples, a light-emitting functional layer is formed on a side of the pixel defining layer away from the base substrate, including: a first light-emitting material layer, a charge generating layer and a second light-emitting material layer are sequentially formed on a side of the pixel defining layer away from the base substrate; the partition structure is formed on a side of the charge generating layer close to the base substrate, and is configured such that the charge generating layer is disconnected at a position corresponding to the edge of the pixel opening.

[0018] In some examples, it also includes: forming a second electrode layer on the side of the light-emitting functional layer away from the base substrate; the second electrode layer includes a second electrode of each of the light-emitting devices, and a first connecting portion connecting adjacent second electrodes; the partition structure includes a notch, and one of the notches at least partially overlaps with a positive projection of one of the first connecting portions on the base substrate.

[0019] In a third aspect, the present disclosure further provides a display device, which includes the display substrate described in any example of the first aspect above. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a plan view schematic diagram of an AMOLED display substrate in the related art.

[0021] Figure 2 for Figure 1 A schematic cross-sectional view of a display substrate is shown.

[0022] Figure 3 for Figure 1 A schematic cross-sectional view of a sub-pixel in a display substrate is shown.

[0023] Figure 4 It is a schematic diagram of the structure of a light-emitting functional layer.

[0024] Figure 5 Schematic diagram of the structure of another light-emitting functional layer.

[0025] Figure 6 The figure is a curve diagram showing the variation of color coordinates with gray scale when an AMOLED display device displays blue and green images in the related art.

[0026] Figure 7It is a spectrum diagram of an AMOLED display device in the related art when displaying blue and green images.

[0027] Figure 8 The diagram is a plan view of a display substrate provided by the present disclosure.

[0028] Fig. 9 for Figure 8 The figure shows a schematic cross-sectional view of the substrate along AB.

[0029] Fig.10 This is an experimental test diagram of the replacement reaction between aluminum and silver ion solution.

[0030] Fig.11A This is a cross-sectional electron microscope image of the display substrate provided in the present disclosure.

[0031] Fig. 11B This is a spectrum change diagram of the display substrate provided by the present disclosure when displaying low gray scale.

[0032] Fig.12 For preparation Fig. 9 The preparation flow chart of the display substrate is shown.

[0033] Fig.13 This is a specific flow chart of step S3.

[0034] Fig.14 A schematic plan view of another display substrate provided by the present disclosure.

[0035] Fig.15 for Fig.14 The diagram shows a schematic cross-sectional view of the substrate along CD.

[0036] Fig.16 For preparation Fig.15 The preparation flow chart of the display substrate is shown.

[0037] Fig.17 It is a schematic diagram of the shape of the longitudinal section of the partition structure.

[0038] The accompanying drawings are denoted as follows:

[0039] 1. substrate; 2. driving circuit layer; 3. planarization layer; 4. pixel definition layer; 5. light-emitting device layer; 401. pixel opening; 4021. first electrode layer; 402. first electrode; 421. light-emitting functional layer; 403. light-emitting functional part; 4041. second electrode layer; 404. second electrode; 4211. light-emitting material layer; 4211a. first light-emitting material layer; 4211b. second light-emitting material layer; 421a. hole injection layer; 421b. hole transport layer; 421c. electron transport layer; 421d. electron injection layer; 421e. charge generation layer; 101. polyimide layer; 102. buffer layer; 103. first gate insulating layer; 104. second gate insulating layer; 105. interlayer dielectric layer; 201. active layer; 202. gate electrode; 203. drain electrode; 204. source electrode Pole; 301, first electrode plate; 302, second electrode plate; 42, light-emitting device; 41, sub-pixel; 41a, red sub-pixel; 41b, blue sub-pixel; 41c, green sub-pixel; 400, pixel unit; 8, encapsulation layer; 108, first inorganic encapsulation layer; 109, organic encapsulation layer; 110, second inorganic encapsulation layer; 6, partition structure; 61, first partition structure; 62, second partition structure; 61a, first partition part; 61b, second partition part; 62a, third partition part; 62b, fourth partition part; 63, notch; 4021, main body; 4022, second connecting part; 4042, first connecting part; 601, first substructure; 602, second substructure; 406, auxiliary opening; 6011, initial first substructure; 6012, first conductive material layer; 7, spacer. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0041] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantity restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0042] As used herein, "parallel" and "perpendicular" include the described situation and the situation similar to the described situation, and the range of the similar situation 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 error associated with the measurement of a specific 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 can be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity can also be, for example, a deviation within 5°.

[0043] It will be understood that when a layer or an element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present between the layer or element and the other layer or substrate.

[0044] Herein, "electrical connection" includes the situation where components are connected together through an element having some electrical function. There is no particular limitation on the "element having some electrical function" as long as it can transmit and receive electrical signals between connected components. Examples of "element having some electrical function" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other elements having various functions.

[0045] Exemplary embodiments are described herein with reference to cross-sectional views and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of layers and regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are conceivable. Therefore, the exemplary embodiments should not be interpreted as being limited to the shapes of the regions shown herein, but include deviations in shape due to, for example, manufacturing. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to illustrate the actual shapes of regions of the device, and are not intended to limit the scope of the exemplary embodiments.

[0046] In the present disclosure, unless otherwise specified, the term "same-layer arrangement" is used to mean that two layers, parts, components, elements or portions can be formed by the same patterning process, and the two layers, parts, components, elements or portions are generally formed of the same material.

[0047] In the present disclosure, unless otherwise specified, the expression "patterning process" generally includes steps such as photoresist coating, exposure, development, etching, photoresist stripping, etc. The expression "one-time patterning process" means a process of forming patterned layers, components, members, etc. using one mask.

[0048] Figure 1 It is a planar schematic diagram of an AMOLED display substrate in the related art; Figure 2 yes Figure 1 The schematic diagram of the film structure of the substrate along the thickness direction is shown in FIG. Figure 1 and Figure 2 As shown, the display substrate includes a plurality of pixel units 400 arranged in an array, each pixel unit 400 includes a plurality of sub-pixels 41, for example, the pixel unit 400 may include a red sub-pixel, a green sub-pixel and a blue sub-pixel. In terms of structure, Figure 1 and Figure 2 The display substrate shown includes a base substrate 1, a driving circuit layer 2 formed on the base substrate 1, and a pixel definition layer 4 and a light emitting device layer 5 arranged on the side of the driving circuit layer 2 away from the base substrate 1. The pixel definition layer 4 has a plurality of pixel openings 401 penetrating along its thickness direction; the light emitting device layer 5 includes a plurality of light emitting devices 42 corresponding to the pixel openings 401, and one pixel opening 401 defines an effective light emitting area of ​​one light emitting device 42; the driving circuit layer 2 includes a pixel driving circuit electrically connected to the light emitting devices 42 in a one-to-one correspondence. Generally, one sub-pixel 41 may include one light emitting device 42 and a pixel driving circuit electrically connected to the light emitting device 42.

[0049] Figure 3 yes Figure 2 The film layer structure diagram of a sub-pixel 41 in the display substrate along the thickness direction is shown. Figure 3As shown, the pixel driving circuit in the sub-pixel 41 generally includes a thin film transistor and a capacitor structure, and the pixel driving circuit may adopt a circuit structure such as 3T1C, 4T1C, 5T1C, 5T2C, 6T1C, 7T1C or 8T1C. The light-emitting device 42 in the sub-pixel 41 may include a first electrode 402, a light-emitting functional portion 403, and a second electrode 404; wherein the first electrode 402 may be electrically connected to the pixel driving circuit through a metal via, and the first electrode 402 may be an anode, and the anode may be made of materials such as ITO (indium tin oxide), indium zinc oxide (IZO), and zinc oxide (ZnO); the light-emitting functional portion 403 is partially located in the pixel opening 401 and is formed on the first electrode 402, and the light-emitting functional portion 403 may include a small molecule organic material or a polymer molecule organic material, and may be a fluorescent luminescent material or a phosphorescent luminescent material. The material can emit red light, green light, blue light, or white light, etc.; and, according to different actual needs, in different examples, the light-emitting functional part 403 can further include functional layers such as an electron injection layer (EIL), an electron transport layer (ETL), a hole injection layer (HIL), and a hole transport layer (HTL); the second electrode 404 covers the light-emitting functional part 403, and the polarity of the second electrode 404 is opposite to the polarity of the first electrode 402; the second electrode 402 can be a cathode, and the cathode can be made of metal materials such as lithium (Li), aluminum (Al), magnesium (Mg), and silver (Ag).

[0050] Just with Figure 3 As a whole, the corresponding display substrate has a light-emitting device layer 5 including a first electrode layer 4021, a light-emitting functional layer 421, and a second electrode layer 4041. The first electrode layer 4021 includes the first electrodes 402 of each light-emitting device 42, the light-emitting functional layer 421 includes the light-emitting functional portion 403 of each light-emitting device 42, and the second electrode layer 4041 includes the second electrodes 404 of each light-emitting device 42. Usually, the first electrodes 402 of each light-emitting device 42 are independent of each other, and the second electrodes 404 of each light-emitting device 42 are connected over the entire surface; that is, the second electrode layer 4041 is a whole-surface structure provided on the display substrate, and is a common electrode of multiple light-emitting devices 42.

[0051] Figure 4 4 is a schematic diagram of a specific structure of the light-emitting functional layer 421. Figure 4 As shown, the light-emitting functional layer 421 includes a plurality of sub-functional layers. In addition to the light-emitting material layer 4211, the light-emitting functional layer 421 also includes sub-functional layers such as an electron injection layer (EIL) 421d, an electron transport layer (ETL) 421c, a hole injection layer (HIL) 421a, and a hole transport layer (HTL) 421b. For the light-emitting functional layer 421, the material of the light-emitting material layer 4211 and the materials of each sub-functional layer are the key to determining the light-emitting effect of each light-emitting functional part 403.

[0052] In order to improve the luminous effect of the display device, the hole injection layer 421a in most OLED devices at this stage is generally composed of a hole transport material doped with a P-dopant (such as SbCl5, FeCl3 and F4-TCNQ, etc.) material with a very deep LUMO (Lowest Unoccupied Molecular Orbital) energy level. This is because in the above-mentioned hole injection layer 421a, there is a significant spontaneous charge transfer between the hole transport material and the P-dopant, which will ultimately give the hole injection layer 421a a higher conductivity, including a higher lateral hole carrier conductivity. It should be noted that in actual preparation, in order to reduce the preparation cost, in the process of forming the hole injection layer 421a by the evaporation process, CMM (Common Metal Mask) is generally used instead of FMM (Fine Metal Mask). The difference between the two is that CMM is often used to deposit common film layers, such as the hole injection layer 421a and the hole transport layer 421b, etc., which are suitable for production scenarios with relatively low precision requirements; FMM is often used to deposit red, green and blue organic light-emitting material layers 4211 and form sub-pixels 41, which are suitable for production scenarios with extremely high precision requirements (such as high-resolution display screens). In other words, the hole injection layer 421a of the red, green and blue sub-pixels 41 is shared, and the hole injection layer 421a is a whole-surface structure arranged in the display substrate.

[0053] In order to further improve the luminous efficiency of the display device and reduce power consumption, the relevant technology proposes to replace the single-layer luminescent material in the luminescent functional layer 403 with two or more layers of luminescent material layers connected in series, and add a charge generation layer (CGL) between the two layers of luminescent material layers to achieve a double-layer luminescence (Tandem EL) design. The OLED device formed by this design is called a Tandem OLED device.

[0054] Figure 5 FIG. 4 is a schematic diagram showing a structure in which the light-emitting functional layer 421 includes two light-emitting material layers 4211. Figure 4 The light-emitting functional layer 421 shown is different in that: Figure 5The light-emitting functional layer 421 shown includes a first light-emitting material layer 4211a and a second light-emitting material layer 4211b, and a charge generation layer (CGL) 421e is arranged between the two light-emitting material layers 4211. Each light-emitting material layer 4211 is equivalent to an independent light source. After the two light-emitting material layers 4211 are connected in series through the charge generation layer 421e, higher brightness, longer life and lower power consumption can be generated. It should be noted that the charge generation layer 421e usually has a very high lateral conductivity, and similar to the hole injection layer 421a, the charge generation layer CGL of multiple sub-pixels 41 is also shared, that is, it is also formed on the entire surface during the preparation process.

[0055] Next, the technical problems existing in the related art are introduced. As mentioned above, since the hole injection layer 421a has a high lateral conductivity, the charge generation layer 421e also has a high lateral conductivity, and the hole injection layer 421a and the charge generation layer 421e are formed on the entire surface of the display substrate, that is, each light-emitting device 42 shares the same hole injection layer 421a and charge generation layer 421e, which can easily lead to crosstalk between adjacent sub-pixels 41. For example, when the display device displays a blue or green picture, a part of the lateral hole carrier leakage current will flow into the red sub-pixel 41, causing the red sub-pixel to emit light, resulting in a pink picture when displaying white, and this crosstalk phenomenon is more obvious under low grayscale display, resulting in the failure of the Gamma circuit to adjust the brightness or contrast under low grayscale, reducing the display effect of the display device.

[0056] Next, the problems existing in the above-mentioned related technologies are intuitively described using actual measurement results. Figure 6 It is a curve diagram of the change of color coordinates with gray scale when an AMOLED display device displays a blue picture and a green picture in the related art; Figure 7 It is a spectrum diagram of the AMOLED display device in the related art when displaying blue and green images. Figure 6 As can be seen in the blue screen ( Figure 6 (a)) and green screen ( Figure 6 In (b), when the grayscale is less than 64, the color coordinates tend to increase as the grayscale decreases. Figure 7 It can be seen that when a blue picture is displayed, the emitted blue light has poor crosstalk with both green and red light (see curve L1 ), and when a green picture is displayed, the emitted green light has poor crosstalk with red light (see curve L2 ).

[0057] In order to solve at least one of the above technical problems, on the one hand, the present disclosure provides a display substrate. The display substrate provided by the present disclosure is described in detail below in conjunction with the accompanying drawings.

[0058] Figure 8A schematic plan view of a display substrate provided by an embodiment of the present disclosure; Fig. 9 for Figure 8 The figure shows a schematic cross-sectional view of the substrate along the vertical plane AB. Figure 8 As shown, the display substrate provided by the present disclosure includes a plurality of pixel units 400, each pixel unit 400 includes a plurality of sub-pixels 41. Figure 8 Taking the display substrate shown in FIG. 1 as an example, each pixel unit 400 includes a red sub-pixel 41a, a blue sub-pixel 41b, and a green sub-pixel 41c, and each sub-pixel 41 includes a light-emitting device 42. Fig. 9 The display substrate includes, in sequence along the thickness direction thereof, a base substrate 1, a first electrode layer 4021 disposed on the base substrate 1, a pixel defining layer 4 disposed on the side of the first electrode layer 4021 away from the base substrate 1, and a light-emitting functional layer 421 and a second electrode layer 4041 formed on the side of the pixel defining layer 4 away from the base substrate 1. The first electrode layer 4021 includes a first electrode 402 of each light-emitting device 42; the pixel defining layer 4 has a plurality of pixel openings 401 penetrating along the thickness direction thereof; the light-emitting functional layer 421 includes a light-emitting functional portion 403 of each light-emitting device 42, and the orthographic projections of one pixel opening 401, the first electrode 402 and the light-emitting functional portion 403 of one light-emitting device 42 on the base substrate 1 at least partially overlap.

[0059] Continue to refer to Figure 8 and Fig. 9 The display substrate provided by the present disclosure further includes a plurality of partition structures 6. Fig. 9 As shown, the partition structure 6 is arranged on the side of the first electrode layer 4021 away from the base substrate 1, and is configured so that at least part of the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position corresponding to the edge of the pixel opening 401. Specifically, the partition structure 6 provided by the present disclosure includes a first substructure 601 and a second substructure 602 that wraps the first substructure 601. The first substructure 601 and the second substructure 602 are respectively a first conductive material and a second conductive material, and the second conductive material includes a material obtained by a replacement reaction between the first conductive material and the first solution, and the solute in the first solution includes a compound of the second conductive material ion.

[0060] It should be noted that “disconnected at the position corresponding to the edge of the pixel opening 401 ” mentioned herein means that the sub-functional layer in the light-emitting functional layer 421 is a discontinuous structure or a non-integrated structure at the position corresponding to the edge of the pixel opening 401 .

[0061] As an optional specific embodiment, the first conductive material can be aluminum (Al), the second conductive material can be silver (Ag), and the solute of the first solution includes silver nitrate (AgNO3). At this time, the material of the first substructure 601 of the partition structure 6 is aluminum, and the material of the second substructure 602 wrapping the outside of the first substructure 601 is silver; the partition structure 6 is formed by the initial first substructure and the silver nitrate solution undergoing the following replacement reaction: 2Al+3Ag + =2Al 3+ +3Ag, the process of the substitution reaction can be roughly described as follows: metal aluminum (the initial first substructure) is placed in a silver nitrate solution, and a substitution reaction occurs with the silver ions therein, the generated aluminum ions enter the solution, and the generated metal silver adheres to the outside of the metal aluminum, and finally a portion of the edge of the initial first substructure is corroded to form the first substructure 601, while a layer of metal silver is plated on the outside of the first substructure 601. It should be noted that the first conductive material, the second conductive material and the first solution provided in this embodiment are provided based on materials commonly used in existing preparation processes, and do not constitute a limitation to the present disclosure. In practical applications, they can be flexibly selected according to needs. For example, the first conductive material can also be metals such as zinc, copper, iron, and magnesium, and the first solution can also be copper sulfate, copper nitrate, ferrous nitrate, bismuth nitrate, silver ammonium nitrate, etc. The corresponding second conductive material can also be bismuth, copper, iron, etc.

[0062] The display substrate provided by the present disclosure is provided with a partition structure 6 so that at least part of the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position corresponding to the edge of the pixel opening 401, which can reduce the crosstalk between two adjacent sub-pixels 41, thereby improving the imaging effect of the display substrate. Furthermore, the partition structure 6 provided by the present disclosure includes a first sub-structure 601 and a second sub-structure 602 that wraps the outside of the first sub-structure 601. The design of the double-layer partition structure can increase the height of the partition structure 6, thereby ensuring the partition effect of the partition structure 6, that is, ensuring that the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position of the partition structure 6.

[0063] Fig.10 This is the appearance and elemental analysis diagram after the substitution reaction between aluminum and silver ions. Fig.10 As shown in FIG. 1 , when metal aluminum is placed in a silver nitrate solution, the edge of the aluminum undergoes a replacement reaction with the silver ions in the etching solution, causing the edge of the aluminum to be corroded while a layer of silver is attached to it; Fig.10 It can be seen that the color of the aluminum edge has changed significantly, and silver elements have been detected at the aluminum edge, proving that an aluminum-silver substitution reaction has occurred at the aluminum edge.

[0064] Fig.11A for Fig. 9 The cross-sectional electron microscope image of the substrate is shown in FIG. Fig.11A As shown, the light-emitting functional layer 421 is disconnected at the position where the partition structure 6 is located, proving that in the display substrate provided by the present disclosure, the partition structure 6 can effectively disconnect the light-emitting functional layer 421 at the position corresponding to the edge of the pixel opening 401, thereby preventing adverse crosstalk between adjacent sub-pixels 41.

[0065] Fig. 11B for Fig. 9 The diagram shown is a spectrum change diagram when the display substrate displays low grayscale. Fig. 11B In the figure, curve LA represents the Fig. 9 The curve LB shows the low grayscale spectrum change curve when the partition structure 6 is used, and the curve LB shows the low grayscale spectrum change curve when the partition structure 6 is not used. By comparison, it can be found that compared with the curve LB, when the partition structure 6 is used, Fig. 9 When the partition structure 6 is shown, the red spectrum intensity of the display substrate caused by crosstalk is significantly reduced. Therefore, the display substrate provided by the present disclosure can ensure the low grayscale image quality of the AMOLED display screen.

[0066] Based on the same inventive concept, in a second aspect, the present disclosure also provides a method for preparing the display substrate as described in the first aspect. Fig.12 The figure is a schematic diagram of the process of preparing the display substrate provided by the present disclosure. Fig.12 As shown, the preparation method comprises:

[0067] Step S1, providing a substrate 1.

[0068] Exemplarily, the substrate 1 can be made of one or more materials selected from glass, polyimide, polycarbonate, polyacrylate, polyetherimide, and polyethersulfone, but is not limited thereto. The substrate 1 can be a rigid substrate or a flexible substrate. When the substrate 1 is a flexible substrate, it can include a first flexible material layer, a first inorganic material layer, a semiconductor layer, a second flexible material layer, and a second inorganic material layer stacked in sequence; wherein the materials of the first flexible material layer and the second flexible material layer can be polyimide (PI), polyethylene terephthalate (PET), or a surface-treated polymer soft film; the materials of the first inorganic material layer and the second inorganic material layer are silicon nitride (SiNx) or silicon oxide (SiOx), etc., which are used to improve the water and oxygen resistance of the substrate. The first inorganic material layer and the second inorganic material layer can also be referred to as a barrier layer or a buffer layer.

[0069] Step S2: forming a first electrode layer 4021 on the base substrate 1.

[0070] In some examples, the first electrode layer 4021 is an anode layer, and the first electrode 402 is an anode. In this case, the material of the first electrode layer 4021 can be a transparent conductive material with a high work function, such as indium tin oxide (ITO), which has high transparency and good conductivity. In other examples, the first electrode layer 4021 can also be made of a metal material, such as any one or more of magnesium Mg, silver Ag, copper Cu, titanium Ti and molybdenum Mo, or an alloy material of the above metals, such as aluminum neodymium alloy AlNd; in addition, the first electrode layer 4021 can be a single-layer structure, a multi-layer composite structure, or a stacked structure formed by metal and transparent conductive materials, such as reflective materials such as ITO / Ag / ITO, Mo / AlNd / ITO, etc.

[0071] Step S3: forming an initial first substructure 6011 on the side of the first electrode layer 4021 away from the substrate 1 . The material of the initial first substructure 6011 is a first conductive material.

[0072] Step S4: Using the first solution, patterning the first electrode layer 4021 to form the first electrode 402 of each light-emitting device 42; at the same time, using the replacement reaction between the first solution and the first conductive material, forming the first substructure 601 of the partition structure 6 and the second substructure 602 that wraps the first substructure 601. The material of the second substructure 602 is the second conductive material, and the solute of the first solution includes a compound of the second conductive material ions.

[0073] As a specific embodiment, the first conductive material is aluminum, the second conductive material is silver, and the first solution includes silver nitrate AgNO3. At this time, the material of the first substructure 601 of the partition structure 6 is aluminum, and the material of the second substructure 602 that wraps the first substructure 601 is silver; the partition structure 6 is formed by the initial first substructure 6011 and the silver nitrate solution undergoing the following substitution reaction: 2Al+3Ag + =2Al 3+ +3Ag, the process of the substitution reaction can be roughly described as follows: the metal aluminum (the initial first substructure 6011) is placed in a silver nitrate solution, and a substitution reaction occurs with the silver ions therein. The generated aluminum ions enter the solution, and the generated metal silver adheres to the outside of the metal aluminum, and finally the edge of the initial first substructure is corroded to form the first substructure 601, and at the same time, a layer of metal silver is plated on the outside of the first substructure 601, that is, the final formation is as follows Fig. 9 The partition structure 6 is shown.

[0074] Step S51 : forming a pixel defining layer 4 on a side of the first electrode layer 4021 away from the base substrate 1 .

[0075] Exemplarily, the material of the pixel defining layer 4 may be an organic material, such as polyimide, acrylic or polyethylene terephthalate.

[0076] Step S52 , forming a plurality of pixel openings 401 penetrating along the thickness direction of the pixel defining layer 4 , wherein the orthographic projections of a first electrode 402 and a pixel opening 401 on the base substrate 1 overlap.

[0077] Step S6: forming a light-emitting functional layer 421 on the side of the pixel defining layer 4 facing away from the base substrate 1. The light-emitting functional layer 421 includes the light-emitting functional part 403 of each light-emitting device 42, and the orthographic projections of one pixel opening 401 and the first electrode 402 and the light-emitting functional part 403 of one light-emitting device 42 on the base substrate 1 at least partially overlap; and at least part of the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position corresponding to the edge of the pixel opening 401.

[0078] The display substrate provided by the present disclosure is provided with a partition structure 6 so that at least part of the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position corresponding to the edge of the pixel opening 401, which can reduce the crosstalk between two adjacent sub-pixels 41, thereby improving the imaging effect of the display substrate. Further, the partition structure 6 provided by the present disclosure includes a first sub-structure 601 and a second sub-structure 602 that wraps the outside of the first sub-structure 601. The design of the double-layer partition structure can increase the height of the partition structure 6, thereby ensuring the partition effect of the partition structure 6, that is, ensuring that the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position of the partition structure 6. In addition, during the preparation process of the partition structure 6 provided by the present disclosure, there is no need for a separate preparation process step to form the second sub-structure 602 that is bonded to the outside of the first sub-structure 601. As described in the above preparation method, the second sub-structure 602 is formed simultaneously in the process of etching the first electrode layer 4021 using the first solution to form the first electrode 402 of each light-emitting device 42. Therefore, the display substrate provided by the present disclosure has a simple and efficient process and lower cost during the preparation process.

[0079] Fig.13 This is a specific step of forming the initial first substructure in step S301. Specifically, in step S3, "forming the initial first substructure 6011 on the side of the first electrode layer 4021 away from the substrate 1" specifically includes:

[0080] Step S31 : forming a first conductive material layer 6012 on a side of the first electrode layer 4021 away from the base substrate 1 .

[0081] Step S32 , patterning the first conductive material layer 6012 to form an initial first substructure 6011 .

[0082] For the initial first substructure 6011 and the corresponding pixel opening 401, the longitudinal section of the initial first substructure 6011 has a first bottom side D1 and a second bottom side D2 which are arranged opposite to each other along the thickness of the substrate 1, and a third side D3 and a fourth side D4 which connect the first bottom side D1 and the second bottom side D2. The third side D3 is closer to the first center line L4 than the fourth side D4, and the distances from at least some points on the third side D3 to the first center line L4 are not equal, and the closer the point is to the substrate 1, the shorter the distance to the first center line L4. The first center line L4 is a straight line which passes through the center of the orthographic projection of the pixel opening 401 on the substrate 1 and extends along the thickness direction of the substrate 1. In other words, the longitudinal section of the initial first substructure 6011 is trapezoidal. It should be noted that the "longitudinal section of the initial first substructure 6011" herein may refer to the cross-sectional shape of the initial first substructure 6011 in the direction perpendicular to the plane of the display substrate.

[0083] In some examples, the light-emitting functional layer 421 includes a hole injection layer 421a (see Figure 4 and Figure 5 In the display substrate provided by the present disclosure, the partition structure 6 is disposed on a side of the hole injection layer 421 a close to the base substrate 1 , and the partition structure 6 is configured to at least disconnect the hole injection layer 421 a at a position corresponding to the edge of the pixel opening 401 .

[0084] Since the hole injection layer 421a has a high lateral hole carrier conductivity, and in actual preparation, the hole injection layer 421a of each light-emitting device 42 is shared, which is a whole-surface structure arranged in the display substrate. In the above example, the partition structure 6 is used to disconnect the hole injection layer 421a at the position of the partition structure 6, which can effectively reduce the crosstalk between the two adjacent sub-pixels 41 caused by the hole injection layer 421a with higher conductivity.

[0085] In some examples, the light-emitting functional layer 421 includes a first light-emitting material layer 4211a, a second light-emitting material layer 4211b, and a charge generation layer 421e located between the first light-emitting material layer 4211a and the second light-emitting material layer 4211b (see Figure 5 In the display substrate provided by the present disclosure, the partition structure 6 is disposed on a side of the charge generation layer 421e close to the base substrate 1, and the partition structure 6 is configured to at least disconnect the charge generation layer 421e at a position corresponding to the edge of the pixel opening 401.

[0086] In the above example, by using two layers of light-emitting material layers 4211 as the light-emitting functional part 403 of the light-emitting device 42, the light-emitting efficiency and display brightness of the display substrate can be effectively improved, the power consumption of the display substrate can be reduced, and the life of the display substrate can be extended. However, on the other hand, the charge generation layer 421e usually has a very high lateral conductivity, and the charge generation layer 421e of multiple light-emitting devices 42 is shared. It is formed on the whole surface during the preparation process, which easily leads to crosstalk between adjacent sub-pixels 41, affecting the display quality. The above example uses the partition structure 6 to disconnect the charge generation layer 421e at the position corresponding to the edge of the pixel opening 401, which can reduce the crosstalk between two adjacent sub-pixels 41 caused by the charge generation layer 421e with strong conductivity. In other words, the display substrate provided by the above example of the present disclosure can reduce the crosstalk between adjacent sub-pixels 41 caused by the charge generation layer 421e while improving the light-emitting efficiency and display brightness.

[0087] In some other examples, the first light-emitting material layer 4211a, the charge generation layer 421e, and the second light-emitting material layer 4211b of the light-emitting functional layer 421 are all disconnected at positions corresponding to the edge of the pixel opening 401. Of course, the embodiments of the present disclosure include but are not limited to this, and the first light-emitting material layer 4211a and the charge generation layer 421e may be disconnected at positions corresponding to the edge of the pixel opening 401, while the second light-emitting material layer 4211b may not be disconnected at positions corresponding to the edge of the pixel opening 401.

[0088] For the display substrate provided in the above example, step S6 in the corresponding preparation method specifically includes: using CMM to sequentially evaporate to form a hole injection layer 421a and a hole transport layer 421b; using FMM to sequentially evaporate to form a first light-emitting material layer 4211a that emits light of different colors, and the first light-emitting material layer 4211a may include a red light-emitting layer, a green light-emitting layer and a blue light-emitting layer; using CMM to sequentially evaporate to form an electron transport layer 421c, an electron injection layer 421d, a charge generation layer 421e and a hole transport layer 421b (the hole transport layer 421b here can be regarded as an auxiliary functional layer of the second light-emitting material layer 4211b); using FMM to sequentially evaporate to form a second light-emitting material layer 4211b that emits light of different colors, and the second light-emitting material layer 4211b may include a red light-emitting layer, a green light-emitting layer and a blue light-emitting layer; using CMM to sequentially evaporate to form an electron transport layer 421c and an electron injection layer 421c.

[0089] Continue to refer to Figure 8 and Fig. 9In some examples, the display substrate provided by the present disclosure further includes a second electrode layer 4041 disposed on the side of the light-emitting functional layer 421 away from the base substrate 1, and the second electrode layer 4041 includes the second electrode 404 of each light-emitting device 42, and a first connecting portion 4042 connecting adjacent second electrodes 404. Exemplarily, the second electrode layer 4041 can be a cathode. In particular, the partition structure 6 is as follows Figure 8 As shown, it also includes a notch 63, and the orthographic projections of one notch 63 and one first connecting portion 4042 on the base substrate 1 at least partially overlap. In some examples, the second electrode layer 4041 may also be disconnected at a position corresponding to the edge of the pixel opening 401.

[0090] In the above example, by providing the partition structure 6 with a notch 63, the adjacent second electrodes 404 will not be disconnected at the notch 63, thereby facilitating the transmission of cathode signals between the light-emitting devices 42. It should be noted that the partition structure 6 may have two or more notches 63. Preferably, the size of the notch 63 should not be too large, and it is only necessary to ensure the smooth transmission of the cathode signal. It is understandable that a smaller notch can greatly increase the resistance at the notch 63 position in the light-emitting functional layer 421, thereby effectively hindering the passage of current, and thus effectively avoiding color crosstalk between adjacent sub-pixels 41.

[0091] Accordingly, when the display substrate is as in the above example, its preparation method is as follows Fig.12 , also includes:

[0092] Step S7: forming a second electrode layer 4041 on the side of the light-emitting functional layer 421 away from the base substrate 1. The second electrode layer 4041 includes the second electrodes 404 of each light-emitting device 42 and the first connecting portion 4042 connecting the adjacent second electrodes 404; a notch 63 of the partition structure 6 and the orthographic projection of a first connecting portion 4042 on the base substrate 1 at least partially overlap.

[0093] The above example can also be described in the following manner, that is, the partition structure 6 corresponding to a pixel opening 401 may include a plurality of spaced-apartment sub-partitions, a gap 63 is formed between adjacent sub-partitions, and the orthographic projections of a gap 63 and a first connecting portion 4042 on the base substrate 1 at least partially overlap. Figure 8For example, the partition structure 6 includes a first partition structure 61 and a second partition structure 62, wherein the first partition structure 61 is arranged correspondingly to the pixel opening 401 of the red sub-pixel 41a, and the second partition structure 62 is arranged correspondingly to the pixel opening 401 of the green sub-pixel 41c. Specifically, the first partition structure 61 may include a first partition portion 61a and a second partition portion 61b, and the second partition structure 62 may include a third partition portion 62a and a fourth partition portion 62b; wherein a notch 63 is formed between the first partition portion 61a and the second partition portion 61b, and a notch 63 is formed between the third partition portion 62a and the fourth partition portion 62b, and the orthographic projections of the first connecting portions 4042 of the two adjacent second electrodes 404 and one notch 63 on the base substrate 1 overlap.

[0094] It should be noted that when the partition structure 6 is Figure 8 When the first partition structure 61 and the second partition structure 62 are included, the first partition structure 61 and the second partition structure 62 can be respectively arranged corresponding to the pixel openings 401 of any two of the red sub-pixel 41a, the green sub-pixel 41c and the blue sub-pixel 41b; for example, the first partition structure 61 and the pixel opening 401 of the blue sub-pixel 41c are arranged correspondingly, and the second partition structure 62 and the pixel opening 401 of the red or green sub-pixel are arranged correspondingly.

[0095] Of course, the partition structure 6 may also include a first partition structure 61, a second partition structure 62 and a third partition structure ( Figure 8 ), wherein the first partition structure 61, the second partition structure 62 and the third partition structure are respectively arranged corresponding to the pixel openings 401 of the red sub-pixel 41a, the blue sub-pixel 41b and the green sub-pixel 41c. In this case, crosstalk between the sub-pixels 41 of three different colors can be effectively prevented.

[0096] In addition, the partition structure 6 may also only include the first partition structure 61, which may be arranged corresponding to the pixel opening 401 of any one of the red sub-pixel 41a, the blue sub-pixel 41b and the green sub-pixel 41c. For example, the first partition structure 61 is arranged corresponding to the pixel opening 401 corresponding to the red sub-pixel 41a. In this case, it is equivalent to isolating the red light with the most serious crosstalk from the sub-pixels of other colors, which can avoid the crosstalk between the red sub-pixel and the sub-pixels of other colors to a certain extent, and this example has less impact on the pixel density, and the preparation process is relatively simple compared to other examples.

[0097] As a preferred embodiment, the partition structure 6 corresponding to the pixel opening 401 is provided with a notch 63 at a position that satisfies: the straight line where the diagonal line of the pixel opening 401 is located passes through the notch 63. It should be understood by those skilled in the art that when the pixel density of the display substrate is high and the sub-pixels 41 are arranged closely, the distance between the edges of the effective light-emitting areas of adjacent sub-pixels 41 is small, while the space between the diagonals of the effective light-emitting areas of adjacent sub-pixels is large. By providing the notch at the diagonal of the pixel opening 401, the space between the diagonals of adjacent sub-pixels 41 can be fully utilized, so that the cathode signal can be better transmitted there.

[0098] Next, two examples of position settings of the partition structure 6 are introduced.

[0099] The first one is Figure 8 and Fig. 9 As shown, the partition structure 6 and the corresponding pixel opening 401 overlap in their orthographic projections on the base substrate 1 .

[0100] When the position of the partition structure 6 is set as Fig. 9 As shown, part of the partition structure 6 overlaps with the orthographic projection of the pixel opening 401 on the base substrate 1, and the remaining part overlaps with the orthographic projection of the pixel defining layer 4 on the base substrate 1. At this time, the partition structure 6 and the pixel opening 401 are compactly arranged and do not occupy too much space. Therefore, for a display substrate with a higher pixel density, the pixel density will not be affected, thereby ensuring the resolution and luminous brightness of the display substrate.

[0101] The second one can refer to Fig.14 and Fig.15 , Fig.14 A schematic plan view of another display substrate provided by an embodiment of the present disclosure; Fig.15 for Fig.14 The schematic diagram of the cross section of the substrate along the vertical plane where CD is located is shown in FIG. Fig.14 and Fig.15 As shown, in the display substrate provided by the present disclosure, the pixel defining layer 4 further has a plurality of auxiliary openings 406 penetrating along the thickness direction thereof, and one auxiliary opening 406 is arranged around one pixel opening 401. The partition structure 6 arranged corresponding to the pixel opening 401 overlaps with the orthographic projection of the auxiliary opening 406 arranged around the pixel opening 401 on the base substrate 1.

[0102] Since the partition structure 6 in the display substrate provided by the present disclosure is made of a conductive material, when the partition structure 6 is arranged at a position such as Fig.14 and Fig.15As shown, that is, when the partition structure 6 overlaps with the auxiliary opening 406 arranged around the pixel opening 401 in their positive projection on the substrate, there is no overlap between the partition structure 6 and the first electrode 402. At this time, the partition structure 6 made of conductive material can be prevented from affecting the anode signal transmitted on the first electrode 402, for example, avoiding increasing the conduction resistance of the first electrode 402 and thus affecting the transmission of the anode signal.

[0103] It should be noted that when the position of the partition structure 6 is the second type, a spacer 7 may be formed between the partition structure 6 and the flat layer 3, and the spacer 7 is arranged in the same layer and formed at the same time as the first electrode 402. The spacer 7 can increase the height of the partition structure 6, thereby ensuring that the light-emitting functional layer 421 is disconnected at the position corresponding to the edge of the pixel opening 401, thereby improving the reliability of the partition structure 6.

[0104] When the position of the partition structure 6 is the second type, the corresponding preparation method of the display substrate is as follows Fig.16 As shown, including:

[0105] Step S11, providing a base substrate 1. The material and film structure of the base substrate 1 can refer to the above step S1, which will not be described again.

[0106] Step S12, forming a first electrode layer 4021 on the base substrate 1, and patterning the first electrode layer 421 to form the first electrode 402 of each light-emitting device 42, and forming a plurality of spacers 7 corresponding to the position of the partition structure 6. The material and patterning process of the first electrode layer 4021 can refer to the above steps S2 to S4, and will not be repeated here.

[0107] Step S13, forming a pixel defining layer 4 on the side of the first electrode layer 4021 away from the base substrate 1; and forming a plurality of pixel openings 401 and a plurality of auxiliary openings 406 penetrating along the thickness direction of the pixel defining layer 4. Among them, the orthographic projections of a pixel opening 401 and a first electrode 402 on the base substrate 1 overlap; an auxiliary opening 406 is arranged around a pixel opening 401. For a pixel opening 401, the spacer 7 corresponding to the partition structure 6 arranged corresponding to it and the auxiliary opening 6 surrounding the pixel opening 401 overlap in their orthographic projections on the base substrate 1. The material selection of the pixel defining layer 4 can refer to the above steps S51 and S52, which will not be repeated here.

[0108] Step S14: forming an initial first substructure 6011 on the side of the spacer 7 away from the base substrate 1; the material of the initial first substructure 6011 is a first conductive material. Specifically, the specific steps of forming the initial first substructure 6011 can refer to the above steps S31 and S32, which will not be repeated here.

[0109] Step S15: using the first solution to undergo a replacement reaction with the initial first substructure 6011 to form the first substructure 601 of the partition structure 6 and the second substructure 602 wrapping the first substructure 601. The material of the second substructure 602 is the second conductive material, and the solute of the first solution includes a compound of the second conductive material ions.

[0110] As a specific embodiment, the first conductive material is aluminum, the second conductive material is silver, and the first solution includes silver nitrate AgNO3. At this time, the material of the first substructure 601 of the partition structure 6 is aluminum, and the material of the second substructure 602 that wraps the first substructure 601 is silver; the partition structure 6 is formed by the initial first substructure 6011 and the silver nitrate solution undergoing the following substitution reaction: 2Al+3Ag + =2Al 3+ +3Ag, the process of the substitution reaction can be roughly described as follows: the metal aluminum (the initial first substructure 6011) is placed in a silver nitrate solution, and a substitution reaction occurs with the silver ions therein. The generated aluminum ions enter the solution, and the generated metal silver adheres to the outside of the metal aluminum, and finally the edge of the initial first substructure is corroded to form the first substructure 601, and at the same time, a layer of metal silver is plated on the outside of the first substructure 601, that is, the final formation is as follows Fig.16 The partition structure 6 is shown.

[0111] Step S16: forming a light-emitting functional layer 421 on the side of the pixel defining layer 4 facing away from the base substrate 1. The light-emitting functional layer 421 includes the light-emitting functional part 403 of each light-emitting device 42, and the orthographic projections of one pixel opening 401 and the first electrode 402 and the light-emitting functional part 403 of one light-emitting device 42 on the base substrate 1 at least partially overlap; and at least part of the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position corresponding to the edge of the pixel opening 401.

[0112] Exemplarily, the light-emitting functional layer 421 includes a first light-emitting material layer 4011a, a charge generating layer 421e and a second light-emitting material layer 4011b. Of course, the light-emitting functional layer 421 may also include a hole injection layer 421a, a hole transport layer 421b, an electron injection layer 421d and a charge transport layer 421c for auxiliary light emission. Among them, the materials of the first light-emitting material layer 4011a and the second light-emitting material layer 4011b can be selected from pyrene derivatives, anthracene derivatives, fluorene derivatives, perylene derivatives, styrylamine derivatives, metal complexes, etc.; the material of the hole injection layer 421a may include oxides or organic materials, such as hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), 1,2,3-tri[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane, etc.; the material of the hole transport layer 421b may include aromatic amines with hole transport properties and dimethylfluorene or carbazole materials, etc.; the charge generation layer 421e is configured to generate carriers, transport carriers and inject carriers, and its materials may include N-type doped organic layer / inorganic metal oxide, or N-type doped organic layer / organic layer, or N-type doped organic layer / P-type doped organic layer, etc.

[0113] Step S17: forming a second electrode layer 4041 on the side of the light-emitting functional layer 421 away from the base substrate 1. The second electrode layer 4041 includes the second electrodes 404 of each light-emitting device 42 and a first connecting portion 4042 connecting adjacent second electrodes 404.

[0114] Continue to refer to Fig. 9 and Fig.15 The display substrate provided by the present disclosure further includes a driving circuit layer 2 disposed on a side of the first electrode layer 4021 close to the base substrate 1, and the driving circuit layer 2 includes a plurality of pixel driving circuits. The specific structure of the pixel driving circuit can be referred to Figure 3 , which includes a thin film transistor and a capacitor structure.

[0115] Specifically, the thin film transistor may be a top-gate type, including an active layer 201, a first gate insulating layer 103, a gate electrode 202, a second gate insulating layer 104, an interlayer dielectric layer 105, a source electrode 204, and a drain electrode 203. Specifically, the active layer 201 may be formed on the buffer layer 102, the first gate insulating layer 103 covers the buffer layer 102 and the active layer 201, the gate electrode 202 is formed on a side of the first gate insulating layer 103 away from the active layer 201, the second gate insulating layer 104 covers the gate electrode 202 and the first gate insulating layer 103, the interlayer dielectric layer 105 covers the second gate insulating layer 104, the source electrode 204 and the drain electrode 203 are formed on a side of the interlayer dielectric layer 105 away from the substrate 1 and are respectively located on opposite sides of the gate electrode 202, and the source electrode 204 and the drain electrode 203 may be in contact with opposite sides of the active layer 201 through vias (e.g., metal vias), respectively.

[0116] The capacitor structure may include a first plate 301 and a second plate 302, wherein the first plate 301 is disposed in the same layer as the gate 202, and the second plate 302 is located between the second gate insulating layer 104 and the interlayer dielectric layer 105, and is disposed opposite to the first plate 301. The materials of the gate 202, the first plate 301, and the second plate 302 may include metal materials or alloy materials, such as molybdenum, aluminum, and titanium. The source 204 and the drain 203 may include metal materials or alloy materials, such as a metal single layer or multilayer structure formed by molybdenum, aluminum, and titanium, for example, the multilayer structure is a multi-metal layer stack, such as a titanium, aluminum, and titanium three-layer metal stack (Ti / Al / Ti), etc.

[0117] Correspondingly, the method for preparing the display substrate further includes the step of forming a pixel driving circuit for each sub-pixel 41 in the driving circuit layer 2 .

[0118] In addition, when the thin film transistor is a top-gate type, a planarization layer 3 may be formed before forming the light-emitting device 42 and the pixel defining layer 4. The planarization layer 3 may be a single-layer structure or a multi-layer structure. Generally, the planarization layer is usually made of organic materials, such as photoresist, acrylic polymer, silicon polymer and the like.

[0119] Correspondingly, the method for preparing the display substrate further includes the steps of forming the above-mentioned planarization layer 3 and connecting vias for connecting the first electrode 402 of the light-emitting device 42 and the pixel driving circuit.

[0120] Reference Figure 8 and Fig.14In the display substrate provided by the present disclosure, the first electrode 402 includes a first main body portion 4021 and a second connection portion 4022 connected to the first main body portion 4021, and one second connection portion 4022 is electrically connected to one pixel driving circuit. Specifically, one second connection portion 4022 is electrically connected to the drain electrode 203 of the thin film transistor in the pixel driving circuit through a metal via on the planarization layer 3. In the display substrate provided by the present disclosure, the partition structure 6 and the orthographic projection of the second connection portion 4022 on the base substrate 1 do not overlap, or in other words, the notch 63 of the partition structure 6 and the orthographic projection of the second connection portion 4022 on the base substrate 1 overlap.

[0121] When the position of the partition structure 6 is set as Figure 8 and Fig. 9 As shown, the notch 63 of the partition structure 6 and the orthographic projection of the second connecting portion 4022 on the base substrate 1 overlap, that is, the second connecting portion 4022 is arranged at the position of the notch 63, which can avoid the partition structure 6 made of conductive material from transmitting signals between the pixel driving circuit and the second connecting portion 4022, thereby avoiding the transmission of the anode signal.

[0122] When the position of the isolation structure 6 is set as Fig.14 and Fig.15 As shown, the notch 63 of the partition structure 6 and the orthographic projection of the second connection part 4022 on the base substrate 1 overlap, that is, the second connection part 4022 is arranged at the position of the notch 63, which can avoid multiple etching of the second connection part 4022 in the process of forming the partition structure 6 using the etching solution, thereby avoiding the second connection part 4022 from being corroded and broken in the process of forming the partition structure 6, thereby affecting the transmission of the anode signal.

[0123] Next, the cross-sectional shape of the partition structure 6 will be described.

[0124] Fig.17 Schematic diagram of the longitudinal section of the partition structure 6 in the display substrate provided by the present disclosure. It should be noted that the longitudinal section of the partition structure 6 herein refers to the shape of the partition structure 6 projected on a plane perpendicular to the display substrate, for example, Figure 8 The vertical plane where the AB line is shown, or Fig.14 The shape of the projection on the vertical plane where the CD line is shown. Fig.17As shown, for the partition structure 6 and the corresponding pixel opening 401, the longitudinal section of the partition structure 6 has a first side S1 and a second side S2 that are relatively arranged along the thickness direction of the substrate 1, and a third side S3 and a fourth side S4 that connect the first side S1 and the second side S2, wherein the third side S3 is closer to the first center line L4 than the fourth side S4. The distances from at least some points on the third side S3 to the first center line L4 are not equal, and the points that are closer to the substrate 1 have longer distances to the first center line L4; wherein the first center line L4 is a straight line that passes through the center of the orthographic projection of the pixel opening 401 on the substrate 1 and extends along the thickness direction of the substrate 1. For example Fig.13 As shown, the distances between two points on the third side S3 and the first center line L4 are d1 and d2 respectively, wherein the distance d2 between the point closer to the substrate 1 and the first center line L4 is greater than the distance d1 between the point farther from the substrate 1 and the first center line L4.

[0125] In other words, the partition structure 6 provided in the present disclosure has a recessed portion on the side wall closer to the first center line L4, or has a protrusion 64 extending toward the first center line L4 on the side wall closer to the first center line L4, and the protrusion 64 is suspended. Fig.17 The cross-sectional shape shown is also called an Under Cut morphology. The partition structure 6 having such a morphology can better ensure that the sub-functional layer in the light-emitting functional layer 421 is disconnected at the protrusion 64, thereby improving the partition effect of the partition structure 6 and thus improving the anti-crosstalk effect of the display substrate.

[0126] In some examples, the display substrate provided by the present disclosure further includes an encapsulation layer 8 formed on the side of the second electrode layer 4041 away from the base substrate 1. The encapsulation layer 8 may be as follows: Figure 3 As shown, it includes a first inorganic encapsulation layer 108, an organic encapsulation layer 109 and a second inorganic encapsulation layer 110. Exemplarily, the first inorganic encapsulation layer 108 and the second inorganic encapsulation layer 110 can be made of inorganic materials such as silicon nitride and silicon oxide; the organic encapsulation layer 109 is used to achieve a planarization effect to facilitate the production of the second inorganic encapsulation layer 110, and the organic encapsulation film layer 118b can be made of materials such as acrylic polymers and silicon polymers.

[0127] Accordingly, the method for preparing the display substrate further includes the step of forming the above-mentioned encapsulation layer 8. For example, the first inorganic encapsulation layer 108 is formed by a chemical vapor deposition process or a physical vapor deposition process; the organic encapsulation layer 109 is formed by an inkjet printing process or a spraying process; and the second inorganic encapsulation layer 110 is formed by a chemical vapor deposition process or a physical vapor deposition process.

[0128] In a third aspect, the present disclosure further provides a display device, which includes a display substrate provided by any of the above examples.

[0129] In summary, the display substrate provided by the present disclosure, by providing a partition structure 6, enables at least part of the sub-functional layers in the light-emitting functional layer 421 to be disconnected at the position corresponding to the edge of the pixel opening 401, which can reduce the crosstalk between two adjacent sub-pixels 41, thereby improving the imaging effect of the display substrate. Furthermore, the partition structure 6 provided by the present disclosure includes a first sub-structure 601 and a second sub-structure 602 that wraps the outside of the first sub-structure 601. The design of the double-layer partition structure can increase the height of the partition structure 6, thereby ensuring the partition effect of the partition structure 6, that is, ensuring that the sub-functional layers in the light-emitting functional layer 421 are disconnected at the position of the partition structure 6. In addition, during the preparation process of the partition structure 6 provided by the present disclosure, there is no need for a separate preparation process step to form a second substructure 602 that is bonded to the outer side of the first substructure 601. As described in the above preparation method, the second substructure 602 is formed simultaneously in the process of etching the first electrode layer 4021 using the first solution to form the first electrode 402 of each light-emitting device 42. Therefore, the display substrate provided by the present disclosure has a simple and efficient process during the preparation process, and the cost is also lower.

[0130] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A display substrate, comprising: substrate substrate; A first electrode layer, disposed on the base substrate, wherein the first electrode layer includes a first electrode of each light emitting device; A pixel defining layer, disposed on a side of the first electrode layer away from the base substrate, the pixel defining layer having a plurality of pixel openings penetrating along a thickness direction thereof; A light-emitting functional layer, arranged on a side of the pixel defining layer away from the base substrate, the light-emitting functional layer including a light-emitting functional part of each of the light-emitting devices; The orthographic projections of one pixel opening and the first electrode and the light-emitting functional part of one light-emitting device on the base substrate at least partially overlap; A plurality of partition structures are arranged on a side of the first electrode layer away from the base substrate, and the partition structures are configured to disconnect at least part of the sub-functional layers in the light-emitting functional layer at a position corresponding to the edge of the pixel opening; wherein, The partition structure includes a first substructure and a second substructure wrapping the first substructure; the materials of the first substructure and the second substructure are a first conductive material and a second conductive material, respectively; the second conductive material includes a material obtained by a replacement reaction between the first conductive material and a first solution, and the solute in the first solution includes a compound of ions of the second conductive material.

2. The display substrate according to claim 1, wherein: The first conductive material includes aluminum, the second conductive material includes silver, and the solute of the first solution includes silver nitrate.

3. The display substrate according to claim 1, wherein: It also includes a second electrode layer disposed on a side of the light-emitting functional layer away from the base substrate; The second electrode layer includes the second electrodes of the light-emitting devices and a first connecting portion connecting the adjacent second electrodes; The partition structure comprises a notch, and an orthographic projection of one of the notch and one of the first connecting portions on the base substrate at least partially overlaps.

4. The display substrate according to claim 1, wherein: It also includes a driving circuit layer disposed on a side of the first electrode layer close to the base substrate, wherein the driving circuit layer includes a plurality of pixel driving circuits; The first electrode comprises a first main body portion and a second connecting portion connected to the first main body portion, and one second connecting portion is electrically connected to one pixel driving circuit; The partition structure and the second connecting portion have no overlap in their orthographic projections on the base substrate.

5. The display substrate according to claim 1, wherein: The partition structure and the corresponding pixel opening have overlapping orthographic projections on the base substrate.

6. The display substrate according to claim 1, wherein: The pixel defining layer also has a plurality of auxiliary openings penetrating along the thickness direction thereof, and one of the auxiliary openings is arranged around one of the pixel openings; The partition structure corresponding to the pixel opening overlaps with the orthographic projection of the auxiliary opening arranged around the pixel opening on the base substrate.

7. The display substrate according to claim 5 or 6, wherein: For the partition structure and the corresponding pixel opening, the longitudinal section of the partition structure has a first side and a second side that are oppositely arranged along the thickness direction of the substrate, and a third side and a fourth side connecting the first side and the second side, and the third side is closer to the first center line than the fourth side; At least some points on the third side have different distances from the first center line, and the points closer to the substrate have longer distances from the first center line; The first center line is a straight line that passes through the center of the orthographic projection of the pixel opening on the base substrate and extends along the thickness direction of the base substrate.

8. The display substrate according to claim 1, wherein: The light-emitting functional layer includes a hole injection layer; The partition structure is disposed on a side of the hole injection layer close to the base substrate, and the partition structure is configured to disconnect the hole injection layer at a position corresponding to the edge of the pixel opening.

9. The display substrate according to claim 1, wherein: The light-emitting functional layer includes a first light-emitting material layer, a second light-emitting material layer, and a charge generation layer located between the first light-emitting material layer and the second light-emitting material layer; The partition structure is disposed on a side of the charge generation layer close to the base substrate, and the partition structure is configured to disconnect the charge generation layer at a position corresponding to the edge of the pixel opening.

10. A method for preparing a display substrate, the display substrate being as claimed in any one of claims 1 to 9, wherein: The preparation method comprises: providing a substrate base plate; forming a first electrode layer on the base substrate; An initial first substructure is formed on a side of the first electrode layer away from the substrate; the material of the initial first substructure is a first conductive material; The first electrode layer is patterned using a first solution to form a first electrode of each light-emitting device; at the same time, the first solution is used to undergo a replacement reaction with the initial first substructure to form a partition structure; The partition structure includes a first substructure and a second substructure wrapping the first substructure, the materials of the first substructure and the second substructure are the first conductive material and the second conductive material respectively; the second conductive material includes a material obtained by a replacement reaction between the first conductive material and the first solution, and the solute in the first solution includes a compound of ions of the second conductive material; A pixel defining layer is formed on a side of the first electrode layer away from the base substrate, and a plurality of pixel openings are formed penetrating along a thickness direction of the pixel defining layer; A light-emitting functional layer is formed on the side of the pixel defining layer away from the base substrate; the light-emitting functional layer includes a light-emitting functional portion of each of the light-emitting devices, and the orthographic projections of one pixel opening and the first electrode and the light-emitting functional portion of one of the light-emitting devices on the base substrate at least partially overlap; and at least part of the sub-functional layers in the light-emitting functional layer are disconnected at a position corresponding to the edge of the pixel opening.

11. The preparation method according to claim 10, wherein: On a side of the first electrode layer facing away from the substrate, an initial first substructure is formed, comprising: forming a first conductive material layer on a side of the first electrode layer away from the substrate; Patterning the first conductive material layer to form the initial first substructure; For the initial first substructure and the corresponding pixel opening, the longitudinal section of the initial first substructure has a first bottom edge and a second bottom edge relatively arranged along the thickness of the substrate, and a third side edge and a fourth side edge connecting the first bottom edge and the second bottom edge; the third side edge is closer to the first center line than the fourth side edge; at least some points on the third side edge have different distances from the first center line, and the closer the point to the substrate, the shorter the distance to the first center line; the first center line is a straight line that passes through the center of the positive projection of the pixel opening on the substrate and extends along the thickness direction of the substrate.

12. The preparation method according to claim 10, wherein: While forming a plurality of pixel openings penetrating along the thickness direction of the pixel defining layer, the method further includes: A plurality of auxiliary openings are formed to penetrate the pixel defining layer in the thickness direction; one of the auxiliary openings is arranged around one of the pixel openings; the partition structure arranged corresponding to the pixel opening overlaps with the positive projection of the auxiliary opening arranged around the pixel opening on the base substrate.

13. The preparation method according to claim 10, wherein: The light-emitting functional layer is formed on a side of the pixel defining layer away from the base substrate, comprising: On a side of the pixel defining layer away from the base substrate, a first light-emitting material layer, a charge generating layer and a second light-emitting material layer are sequentially formed; The partition structure is formed on a side of the charge generation layer close to the base substrate, and is configured to disconnect the charge generation layer at a position corresponding to the edge of the pixel opening.

14. The preparation method according to claim 10, wherein: Also includes: forming a second electrode layer on a side of the light-emitting functional layer away from the base substrate; The second electrode layer includes the second electrodes of the light-emitting devices and a first connecting portion connecting the adjacent second electrodes; The partition structure comprises a notch, and one of the notches at least partially overlaps with an orthographic projection of one of the first connecting portions on the base substrate.

15. A display device comprising the display substrate according to any one of claims 1 to 9.

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