Display substrate and manufacturing method therefor, and display device

Abstract

A display substrate, comprising: a substrate and a pixel defining layer, wherein the pixel defining layer is located on the substrate; the pixel defining layer comprises a plurality of first barrier walls and a plurality of second barrier walls; the plurality of first barrier walls extend in a first direction, and the plurality of second barrier walls extend in a second direction, the first direction intersecting with the second direction; the plurality of first barrier walls and the plurality of second barrier walls are connected to each other and define a plurality of openings; a plurality of light-emitting units are located in the plurality of openings in a one-to-one correspondence; and in the second direction, the height of each of the plurality of first barrier walls gradually increases and then gradually decreases, and the direction of the height is perpendicular to the substrate.

Description

Display substrate and manufacturing method thereof, and display device

[0001] This application claims priority to Chinese patent application No. 202410140174.1, filed on January 31, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates to the field of display technology, and in particular to a display substrate and a preparation method thereof, and a display device. Background Art

[0003] Electroluminescent display devices have become the mainstream development trend of current display devices due to their advantages such as self-luminescence, low power consumption, wide viewing angle, fast response speed and high contrast.

[0004] Currently, a full coating technique such as doctor blade coating or slit coating is often used to form a light-emitting layer in the opening of the pixel defining layer. Summary of the Invention

[0005] On the one hand, a display substrate is provided, which includes: a substrate and a pixel defining layer, wherein the pixel defining layer is located on one side of the substrate; the pixel defining layer includes a plurality of first retaining walls and a plurality of second retaining walls; the plurality of first retaining walls extend along a first direction, and the plurality of second retaining walls extend along a second direction, and the first direction and the second direction intersect; the plurality of first retaining walls and the plurality of second retaining walls are connected and enclosed to form a plurality of openings; a plurality of light-emitting units are located in the plurality of openings in a one-to-one correspondence; along the second direction, the height of each of the plurality of first retaining walls gradually increases and then gradually decreases, and the direction of the height is perpendicular to the substrate.

[0006] In some embodiments, in any cross section of the first barrier wall perpendicular to the substrate, along the second direction, portions of the first barrier wall located on opposite sides of the highest position of the first barrier wall have different height change rates.

[0007] In some embodiments, in the longitudinal section of the first retaining wall, the angle formed between the first retaining wall and the plane where the substrate is located includes: a first slope angle and a second slope angle, the angle of the first slope angle is greater than the angle of the second slope angle; the longitudinal section of the first retaining wall is perpendicular to the substrate and perpendicular to the first direction.

[0008] In some embodiments, the angle difference between the first slope angle and the second slope angle ranges from 5° to 65°.

[0009] In some embodiments, the first slope angle ranges from 35° to 70°; the second slope angle ranges from 5° to 30°.

[0010] In some embodiments, the maximum height of the first retaining wall is less than or equal to 1 μm and greater than or equal to 0.5 μm.

[0011] In some embodiments, the height of the second retaining wall is greater than the maximum height of the first retaining wall.

[0012] In some embodiments, the height of the second retaining wall ranges from 1 μm to 2 μm.

[0013] In some embodiments, the first retaining wall includes: a plurality of retaining wall portions arranged in sequence along the first direction, a first gap being formed between each two adjacent retaining wall portions of the plurality of retaining wall portions; in an orthographic projection onto the substrate, the first gap is located within the second retaining wall; and a portion of the second retaining wall is filled within the first gap.

[0014] In some embodiments, the material of the first retaining wall includes a first lyophilic material; the second retaining wall includes a first material layer and a second material layer sequentially away from the substrate, the material of the first material layer includes a second lyophilic material, and the material of the second material layer includes a lyophobic material; wherein the first lyophilic material and the second lyophilic material have lyophilic properties to the light-emitting layer material in the light-emitting unit; and the lyophobic material has lyophobic properties to the light-emitting layer material.

[0015] In some embodiments, the first lyophilic material and the second lyophilic material are the same.

[0016] In some embodiments, a height of the first material layer is greater than a height of the second material layer.

[0017] In some embodiments, a height of the first material layer is greater than or equal to a height of the first retaining wall.

[0018] In some embodiments, the maximum size of the first retaining wall in the second direction is greater than the size of the second retaining wall in the first direction.

[0019] In some embodiments, the display substrate further comprises: an anode layer disposed between the substrate and the pixel defining layer; the anode layer comprising a plurality of anode patterns, the plurality of anode patterns being disposed in a one-to-one correspondence with the plurality of openings. A second spacing is defined between each adjacent two of the plurality of anode patterns along the first direction, with a portion of the second retaining wall filling the second spacing; a third spacing is defined between each adjacent two of the plurality of anode patterns along the second direction, with a portion of the first retaining wall filling the third spacing; and in an orthographic projection onto the substrate, the maximum height of the first retaining wall is located within the third spacing.

[0020] In another aspect, a method for preparing a display substrate is provided, the method comprising: forming a substrate and forming a pixel defining layer on one side of the substrate. Forming the pixel defining layer on one side of the substrate comprises: forming a plurality of first retaining walls, the plurality of first retaining walls extending along a first direction, the height of each of the plurality of first retaining walls gradually increasing and then decreasing along a second direction, the height direction being perpendicular to the substrate, and the first and second directions intersecting; forming a plurality of second retaining walls on a side of the plurality of first retaining walls away from the substrate, the plurality of second retaining walls extending along the second direction; the plurality of first retaining walls and the plurality of second retaining walls being connected to form a plurality of openings; and a plurality of light-emitting units being positioned in the plurality of openings in a one-to-one correspondence.

[0021] In some embodiments, the method for preparing a display substrate further includes: applying ink in the opening to form a functional layer, wherein applying ink in the opening to form a functional layer includes: applying ink in the opening along the second direction by a coating device to obtain a functional layer.

[0022] In some embodiments, applying ink in the opening portion includes: applying ink in the opening portion along a direction from the second slope angle of the first retaining wall to the first slope angle of the first retaining wall using a coating device; wherein the angle of the first slope angle is greater than the angle of the second slope angle.

[0023] In another aspect, a display device is provided, comprising: a display substrate as described in any one of the above embodiments; and a driver chip configured to drive the display substrate to perform display. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] To more clearly illustrate the technical solutions of the present disclosure, the following briefly introduces the drawings required for use in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure, and those skilled in the art can also derive other drawings based on these drawings. Furthermore, the drawings described below are schematic diagrams and are not intended to limit the actual dimensions of the products, actual processes of the methods, etc. involved in the embodiments of the present disclosure.

[0025] FIG1 is a structural diagram of a display device according to some embodiments of the present disclosure;

[0026] FIG2 is a diagram illustrating a region division structure of a display panel according to some embodiments of the present disclosure;

[0027] FIG3 is a structural diagram of a display panel according to some embodiments of the present disclosure;

[0028] FIG4 is a structural diagram of a pixel definition layer according to some embodiments;

[0029] FIG5 is a surface profile diagram of a functional layer of a display substrate according to some embodiments of the present disclosure;

[0030] FIG6 is a structural diagram of a display substrate according to some embodiments of the present disclosure;

[0031] FIG7 is a cross-sectional view of the display substrate along section line EE according to FIG6 ;

[0032] FIG8 is a cross-sectional view of the display substrate along the cross-sectional line FF provided in FIG6 ;

[0033] FIG9 is a cross-sectional view of the display substrate along the cross-sectional line GG provided in FIG6 ;

[0034] FIG10 is another cross-sectional view of the display substrate along the cross-sectional line FF according to FIG6 ;

[0035] FIG11 is a structural diagram of a first retaining wall according to some embodiments of the present disclosure;

[0036] FIG12 is another structural diagram of a first retaining wall according to some embodiments of the present disclosure;

[0037] FIG13 is another structural diagram of a display substrate according to some embodiments of the present disclosure;

[0038] FIG14 is a cross-sectional view of the display substrate provided in FIG13 along section line II;

[0039] FIG15 is a flow chart of a method for preparing a display substrate according to some embodiments of the present disclosure;

[0040] 16 and 17 are structural diagrams corresponding to steps of a method for preparing a display substrate according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0041] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the embodiments described are only some embodiments of the present disclosure, not all embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present disclosure.

[0042] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and its other forms, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open and inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" are intended to indicate that the particular features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0043] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0044] When describing some embodiments, the expressions "coupled" and "connected" and their derivatives may be used. The term "connected" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. The term "coupled" indicates, for example, that two or more components are in direct physical or electrical contact. The term "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other, but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0045] “At least one of A, B and C” has the same meaning as “at least one of A, B or C” and both include the following combinations of A, B and C: A only, B only, C only, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B and C.

[0046] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0047] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation 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).

[0048] 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 an acceptable deviation range, wherein the acceptable deviation range is as determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the specific quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range 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°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality can be, for example, that the difference between the two equals is less than or equal to 5% of either one.

[0049] It will be understood that when a layer or element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present therebetween.

[0050] Exemplary embodiments are described herein with reference to cross-sectional and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of layers and the area of ​​regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are contemplated. Therefore, the exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include deviations in shape due to, for example, manufacturing. For example, an etched region shown as a rectangle will typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to illustrate the actual shape of regions of the device and are not intended to limit the scope of the exemplary embodiments.

[0051] As shown in FIG1 , some embodiments of the present disclosure provide a display device 1000. Display device 1000 can be any product or component with a display function, such as a television, monitor, laptop, tablet computer, mobile phone, or navigation system. FIG1 illustrates an example of a mobile phone as display device 1000.

[0052] Exemplarily, the display device 1000 can be any device that displays either moving (e.g., video) or stationary (e.g., still images), and whether text or images. More specifically, it is contemplated that the embodiments described herein can be implemented in or associated with a variety of electronic devices, such as, but not limited to, mobile phones, wireless devices, personal data assistants (PDAs), handheld or portable computers, GPS receivers / navigators, cameras, MP4 video players, video cameras, game consoles, watches, clocks, calculators, television monitors, flat-panel displays, computer monitors, automotive displays (e.g., speedometer displays), navigation systems, cockpit controls and / or displays, displays of camera views (e.g., displays of rearview cameras in vehicles), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging, and aesthetic structures (e.g., displays of images of a piece of jewelry), and the like.

[0053] For example, the display device 1000 may be an electroluminescent display device or a photoluminescent display device. In the case where the display device 1000 is an electroluminescent display device, the electroluminescent display device may be an organic light-emitting diode (OLED) or a quantum dot light-emitting diode (QLED). In the case where the display device 1000 is a photoluminescent display device, the photoluminescent display device may be a quantum dot photoluminescent display. The following uses the display device 1000 as a QLED display device as an example to schematically illustrate some embodiments of the present disclosure. However, the embodiments of the present disclosure include but are not limited to these, and any other display device may also be considered as long as the same technical concept is applied.

[0054] Continuing to refer to FIG. 1 , the display device 1000 includes a display panel 100 .

[0055] Since the present disclosure uses the display device 1000 as a QLED display device as an example, when the display device 1000 is a QLED display device, the display panel 100 is a QLED display panel. However, the type of the display panel 100 is not limited thereto and may also be other display panels 100 employing the following structures.

[0056] As shown in FIG2 , the display panel 100 is divided into a display area AA and a peripheral area BB located on at least one side of the display area AA. FIG2 illustrates an example in which the peripheral area BB surrounds the display area AA. The display area AA is provided with a plurality of sub-pixels P, and the sub-pixels P include at least a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B. For example, a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B arranged in sequence form a pixel PP. In some embodiments, as shown in FIG2 , a row of red sub-pixels R, a row of green sub-pixels G, and a row of blue sub-pixels B are arranged alternately in sequence. The peripheral area BB is used for wiring. In addition, the gate drive circuit can also be provided in the peripheral area BB.

[0057] As shown in FIG3 , the display panel 100 includes a display substrate 10 and an encapsulation layer 20 for encapsulating the display substrate 10. Here, the encapsulation layer 20 may be an encapsulation film or an encapsulation substrate. When the encapsulation layer 20 is an encapsulation film, the number of layers of encapsulation film included in the encapsulation layer 20 is not limited; the encapsulation layer 20 may include a single layer of encapsulation film or two or more layers of encapsulation films stacked together.

[0058] As shown in FIG4 , the display substrate 10 includes a functional layer 30, for example, the functional layer 30 is a light-emitting layer. When forming the functional layer 30 of the display substrate 10, commonly used film-forming processes include inkjet printing, slit coating, spin coating, and screen printing. FIG4 takes the nozzle coating film-forming process as an example to form the functional layer 30. During this process, the coating device 200 applies ink to the opening 15 of the pixel defining layer 12. It should be noted that the light-emitting layer material before coating exists in the form of ink, and the ink applied to the opening 15 forms the light-emitting layer material for obtaining the functional layer 30. A drying process is then used to remove excess solvent in the light-emitting layer material, thereby forming the required functional layer 30. The morphology of the functional layer 30 has a significant impact on the display effect of the display device 1000.

[0059] The inventors have discovered that after coating using a full-surface coating technique such as blade coating or slit coating, the uniformity of the functional layer 30 in the opening 15 becomes asymmetric along the coating direction.

[0060] For example, as shown in Figure 4 , the ink is applied in a direction from right to left in the horizontal direction x. After the functional layer 30 is formed by coating, the exposed surface of the functional layer 30 at section line CC is shown in Figure 5 . The ordinate of Figure 5 represents the relative height of the surface profile of the functional layer 30, and the abscissa represents the extension of the display substrate 10 in the horizontal direction x. The profile curve at a relative height of approximately 0 nm represents the surface profile of the functional layer 30 formed in the opening 15 of the pixel defining layer 12 at section line CC. Taking the contour segment D of an opening 15 of the pixel defining layer 12 as an example, the dashed line L1 divides the contour segment D into two left and right sections of approximately equal size in the horizontal direction x. As can be seen in Figure 5 , the relative heights of the functional layer 30 on the left and right sides of the dashed line L1 are asymmetrical. Specifically, the relative height d1 of the functional layer 30 on the left side of the dashed line L1 is higher than the relative height d2 of the functional layer 30 on the right side of the dashed line L1.

[0061] Moreover, the inventors found that one of the reasons for the relative height asymmetry of the surface profile of the functional layer 30 is that: as shown in Figure 4, when the ink is coated along the horizontal direction x from right to left, a leftward shear force will be generated during the coating process, and the ink has a certain viscosity, which causes the pixel defining layer 12 to have a blocking effect on the ink. In each opening 15, the light-emitting layer material is more concentrated on the left side of the opening 15, and the edge of the pixel defining layer 12 on the left side of the opening 15 climbs more severely. After the drying process removes the excess solvent in the light-emitting layer material, the functional layer 30 formed on the left side of the opening 15 is relatively thick, so that the relative height of the surface profile of the functional layer 30 at this location is higher, resulting in poor uniformity of the functional layer 30.

[0062] 6 and 7 , an embodiment of the present disclosure provides a display substrate 10 that can be applied to the above-mentioned display panel 100 . The display substrate 10 includes a substrate 11 and a pixel defining layer 12 located on one side of the substrate 11 .

[0063] For example, the substrate 11 may be made of glass, metal, or any flexible material.

[0064] Exemplarily, the light-emitting layer material of the light-emitting unit includes a quantum dot material, wherein the quantum dot material may include a quantum dot body and a quantum dot ligand structure, and the quantum dot body and the coordination group in the quantum dot ligand are connected by a chemical bond. The quantum dot body may include: any one of: IIB-VIA group quantum dots, IIIA-VA group quantum dots, IVA-VIA group quantum dots, core-shell structure quantum dots and ABX3 type perovskite quantum dots. In the ABX3 type perovskite quantum dots, A is CH3NH3 + (methylamine), NH2CH=NH2(formamidine) and Cs +One or more of, B is Pb 2+ and Sn 2+ One or two of the following, X is Cl - Br - and I - One or more of the ABX3 type perovskite quantum dots include CH3NH3PbBr3, CH3NH3PbCl3, CH3NH3PbI3, CsPbBr3, CsPbCl3 and CsPbI3.

[0065] Exemplarily, the IIB-VIA group quantum dots are selected from: binary compounds such as one or more of CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, and MgS; ternary compounds such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZn Te, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, or mixtures thereof; and quaternary compounds such as HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, or mixtures thereof, but are not limited thereto.

[0066] The IIIA-VA group quantum dots are selected from: binary compounds such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, or mixtures thereof; ternary compounds such as GaNPs, GaNAs, GaNSb, GaPAs, GaPSb, AlNPs, AlNAs, AlNSb, AlPAs, AlPSb, InNPs, InNAs, InNSb, InPAs, InPSb, or mixtures thereof; and quaternary compounds such as GaAlNPs, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNPs, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNPs, InAlNAs, InAlNSb, InAlPAs, InAlPSb, or mixtures thereof, but are not limited thereto.

[0067] Group IVA-VIA quantum dots are selected from, but are not limited to, binary compounds such as SnS, SnSe, SnTe, PbS, PbSe, PbTe, or mixtures thereof; ternary compounds such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, or mixtures thereof; and quaternary compounds such as SnPbSSe, SnPbSeTe, SnPbSTe, or mixtures thereof. Group IVA-VIA quantum dots are selected, for example, from elemental (mono) semiconductors such as Si, Ge, or mixtures thereof; and binary semiconductor compounds such as SiC, SiGe, and mixtures thereof.

[0068] Core-shell quantum dots are structures where one material is the core and the other is the shell. For example, a CdS / ZnS quantum dot is a quantum dot where the core is CdS and the shell is ZnS.

[0069] In some other embodiments, the quantum dot bodies may be other nanoscale materials, such as nanorods, nanosheets, etc. The components of other nanoscale materials may include at least one of CdS, CdSe, CdTe, ZnSe, InP, PbS, CuInS2, ZnO, CsPbCl3, CsPbBr3, CsPhI3, CdS / ZnS, CdSe / ZnS, ZnSe, InP / ZnS, PbS / ZnS, InAs, InGaAs, InGaN, GaNk, ZnTe, Si, Ge, and C.

[0070] For example, the quantum dot body can include cadmium (Cd)-free quantum dots. Cadmium-free quantum dots are quantum dots that do not include cadmium (Cd). Cadmium (Cd) can cause serious environmental / health problems, so non-cadmium-based quantum dots can be effectively used.

[0071] The pixel defining layer 12 includes a plurality of first retaining walls 13 and a plurality of second retaining walls 14. The first retaining walls 13 extend along a first direction Y, and the second retaining walls 14 extend along a second direction X, with the first direction Y and the second direction X intersecting. The plurality of first retaining walls 13 and the plurality of second retaining walls 14 are connected and enclose a plurality of openings 15, and the plurality of light-emitting units are positioned in the plurality of openings 15 in a one-to-one correspondence.

[0072] It should be noted that there is no limitation on the specific number of "plurality". For example, "plurality" means "at least two".

[0073] The first direction Y intersects the second direction X, which means that there is an angle between the first direction Y and the second direction X. For example, the first direction Y and the second direction X are perpendicular to each other. For example, the angle between the first direction Y and the second direction X is an acute angle.

[0074] For example, as shown in Figures 2 and 6 , the embodiments of the present disclosure are described using the example of a first direction Y and a second direction X being perpendicular to each other. The first direction Y is the column direction, and the second direction X is the row direction. Multiple second retaining walls 14 and multiple first retaining walls 13 are arranged in multiple rows and columns. The first retaining walls 13 extend in the column direction, and the second retaining walls 14 extend in the row direction. In this case, the multiple openings 15 formed by the multiple first retaining walls 13 and the multiple second retaining walls 14 are used to accommodate light-emitting layer materials to form a functional layer 30 of multiple subpixels P. The multiple subpixels P include a row of red subpixels R, a row of green subpixels G, and a row of blue subpixels B, which are arranged alternately in sequence.

[0075] As shown in FIG. 7 , along the second direction X, the height h1 of the first retaining wall 13 gradually increases and then gradually decreases, and the direction of the height h1 is perpendicular to the substrate 11 .

[0076] It can be understood that the direction perpendicular to the first direction Y and the second direction X is referred to as the third direction Z, and the height h1 of the first retaining wall 13 is the dimension of the first retaining wall 13 along the third direction Z.

[0077] For example, FIG7 is a cross-sectional view of the display substrate 10 shown in FIG6 along section line EE. FIG7 shows that, along the second direction X, the height h1 of the first retaining wall 13 first gradually increases and then gradually decreases. In other words, along the second direction X, the surface of the first retaining wall 13 away from the substrate 11 is a sloped surface N. When the height h1 of the first retaining wall 13 gradually increases to a maximum, this height h1 represents the maximum height h1a of the first retaining wall 13.

[0078] By setting the height h1 of the first retaining wall 13 to gradually increase and then gradually decrease, the surface of the first retaining wall 13 away from the substrate 11 is a sloped surface N. When applying ink, the sloped surface N can reduce the blocking effect of the first retaining wall 13 on the ink, thereby reducing the accumulation degree of the light-emitting layer material at the edge of the first retaining wall 13 and slowing down the climbing degree of the light-emitting layer material at the first retaining wall 13. The flatness of the functional layer 30 of the sub-pixel P can be effectively improved, and the uniformity of the functional layer 30 of the sub-pixel P can be improved, thereby improving the display effect of the display device 1000.

[0079] In some embodiments, as shown in FIG. 7 , in any cross section of the first retaining wall 13 perpendicular to the substrate 11 , along the second direction X, portions of the first retaining wall 13 located on opposite sides of the highest position L2 have different height change rates.

[0080] For example, taking the longitudinal section S1 of the first retaining wall 13 as an example, the longitudinal section S1 of the first retaining wall 13 is perpendicular to the substrate 11 and perpendicular to the first direction Y. In the longitudinal section S1 of the first retaining wall 13 , along the second direction X, the height h1 of the first retaining wall 13 gradually increases and then gradually decreases, and the direction in which the height h1 is located is perpendicular to the substrate 11 .

[0081] 7 , along the second direction X, the height change rate of the portion located to the left of the highest position L2 of the first retaining wall 13 is smaller, and the height change rate of the portion located to the right of the highest position L2 of the first retaining wall 13 is larger.

[0082] Illustratively, in the longitudinal section S1 of the first retaining wall 13, the parts on both sides of the highest position L2 of the first retaining wall 13 are respectively the first part W1 and the second part W2, and the first part W1 and the second part W2 are asymmetrically arranged relative to the highest position L2 of the first retaining wall 13. The longitudinal section S1 of the first retaining wall 13 is perpendicular to the substrate 11 and perpendicular to the first direction Y.

[0083] It can be understood that the longitudinal section S1 of the first retaining wall 13 is the section in the cross-sectional view of the first retaining wall 13 along the section line EE in FIG. 6 .

[0084] For example, as shown in FIG7 , the height h1 of the first retaining wall 13 gradually increases and then gradually decreases, so that two different slope surfaces N are obtained on both sides of the highest position L2 of the first retaining wall 13 , which are represented as the first slope surface N1 and the second slope surface N2 , respectively.

[0085] The two sloped surfaces N of the first retaining wall 13 form different angles with the plane of the substrate 11. That is, in the longitudinal cross-section S1 of the first retaining wall 13, the angles formed between the first retaining wall 13 and the plane of the substrate 11 include a first slope angle α1 and a second slope angle α2. The first slope angle α1 is the angle between the first sloped surface N1 and the plane of the substrate 11, and the second slope angle α2 is the angle between the second sloped surface N2 and the plane of the substrate 11. Furthermore, the first slope angle α1 and the second slope angle α2 are unequal.

[0086] By setting different height change rates of the parts on both sides of the highest position L2 of the first retaining wall 13 along the second direction X, two slope surfaces N with different slope angles can be obtained. Moreover, the blocking effect of the slope surface N with a smaller slope angle on ink is smaller than the blocking effect of the slope surface N with a larger slope angle on ink.

[0087] It is understandable that when the maximum height h1a of the first retaining wall 13 is fixed and the dimension d3 of the first retaining wall 13 along the second direction X is fixed, a decrease in the slope angle on one side of the first retaining wall 13 will be accompanied by an increase in the slope angle on the other side of the first retaining wall 13.

[0088] That is, by setting different height change rates for portions located on opposite sides of the highest position L2 of the first retaining wall 13 along the second direction X, a sloped surface N with a further reduced slope angle can be formed, for example, a second sloped surface N2 with a reduced second slope angle α2. This sloped surface N can further reduce the ink blocking effect of the first retaining wall 13, reduce the accumulation of light-emitting layer material at the edge of the first retaining wall 13, and slow down the climbing of the light-emitting layer material at the first retaining wall 13. This can effectively improve the flatness of the functional layer 30 of the sub-pixel P, thereby improving the uniformity of the functional layer 30 of the sub-pixel P, thereby improving the display effect of the display device 1000.

[0089] It should be noted that the dimension d3 of the first retaining wall 13 along the second direction X refers to the maximum dimension of the first retaining wall 13 along the second direction X.

[0090] In some embodiments, as shown in FIG. 7 , the first slope angle α1 is greater than the second slope angle α2 .

[0091] For example, as shown in FIG7 , the first slope angle α1 is closer to the highest position L2 of the first retaining wall 13 than the second slope angle α2. Thus, the slope of the second sloped surface N2 is relatively gentle. When the coating device 200 applies ink facing the second sloped surface N2, the second sloped surface N2 has a relatively small blocking effect on the ink. "Facing the second sloped surface N2" means applying ink from left to right in the second direction X, with the second sloped surface N2 facing the direction of movement of the coating device 200.

[0092] In some examples, the angle difference between the first slope angle α1 and the second slope angle α2 ranges from 5° to 65°.

[0093] Illustratively, the angle difference between the first slope angle α1 and the second slope angle α2 is 5°, 10°, 15°, 30°, 35°, 45°, 55° or 65°, etc., which is not limited here.

[0094] By setting the angle difference between the first slope angle α1 and the second slope angle α2 to be in the range of 5° to 65°, the purpose of further reducing the blocking effect of the first retaining wall 13 on ink can be achieved.

[0095] Exemplarily, the first slope angle α1 ranges from 35° to 70°. For example, the first slope angle α1 is 35°, 40°, 50°, 60°, or 70°, etc., which is not limited here.

[0096] Exemplarily, the second slope angle α2 ranges from 5° to 30°. For example, the second slope angle α2 is 5°, 10°, 15°, 20°, 25° or 30°, etc., which is not limited here.

[0097] By setting the first slope angle α1 to a range of 35° to 70° and the second slope angle α2 to a range of 5° to 30°, a slope surface N with a smaller slope angle can be obtained while satisfying the feasibility of the manufacturing process.

[0098] In some embodiments, as shown in FIG. 7 , the maximum height h1a of the first retaining wall 13 is less than or equal to 1 μm and greater than or equal to 0.5 μm, that is, 0.5 μm≤h1a≤1 μm.

[0099] For example, the maximum height h1a of the first retaining wall 13 is 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm or 1 μm, etc., which is not limited here.

[0100] Since the total thickness of the film layer of the light emitting device located in the opening 15 is generally about 0.2 μm, by setting the maximum height h1a of the first retaining wall 13 to 0.5 μm≤h1a≤1 μm, the requirement of forming the light emitting device film layer in the opening 15 can be met.

[0101] In some embodiments, as shown in FIG. 8 and FIG. 9 , the height h2 of the second retaining wall 14 is greater than the maximum height h1a of the first retaining wall h1 .

[0102] It should be noted that, as shown in Figure 9, the second retaining wall 14 has two types of heights h2: a first type height h21 and a second type height h22. At the intersection of the first retaining wall 13 and the second retaining wall 14, the height of the portion of the second retaining wall 14 that overlaps the first retaining wall 13 is the first type height h21 of the second retaining wall 14. The height of the portion of the second retaining wall 14 that does not overlap the first retaining wall 13 is the second type height h22 of the second retaining wall 14.

[0103] Due to the influence of the film forming process, the first type height h21 is smaller than the second type height h22, that is, h21 <h22。

[0104] Here, the height h2 of the second retaining wall 14 is greater than the maximum height h1a of the first retaining wall h1 , which means that the second type height h22 of the first retaining wall 13 is greater than the maximum height h1a of the first retaining wall h1 .

[0105] As shown in FIG8 and FIG9 , by setting the height h2 of the second retaining wall 14 to be greater than the maximum height h1a of the first retaining wall h1 , cross-color caused by the mutual flow of light-emitting layer materials between the openings 15 in adjacent rows can be effectively prevented, thereby improving the display effect of the display device 1000 .

[0106] In some embodiments, as shown in FIG. 8 and FIG. 9 , the height h2 of the second retaining wall 14 ranges from 1 μm to 2 μm.

[0107] It should be noted that, as shown in Figures 8 and 9, the height h2 of the second retaining wall 14 here ranges from 1μm to 2μm, which refers to the second type of height h22 when the second retaining wall 14 does not cover the first retaining wall 13, that is, the second type of height h22 of the second retaining wall 14 ranges from 1μm to 2μm.

[0108] Illustratively, the height h2 of the second retaining wall 14 is 1 μm, 1.2 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.7 μm, 1.9 μm or 2 μm, etc., which is not limited here.

[0109] Setting the height h2 of the second retaining wall 14 to be in the range of 1 μm to 2 μm can effectively prevent cross-color caused by the mutual flow of light-emitting layer materials between the openings 15 in adjacent rows, thereby improving the display effect of the display device 1000 .

[0110] In some embodiments, as shown in FIG8 and FIG9 , the material of the first retaining wall 13 includes a first lyophilic material, and the first lyophilic material has lyophilic properties to the light-emitting layer material in the light-emitting unit.

[0111] The lyophilic property refers to a strong attraction between the first lyophilic material and the light-emitting layer material in the light-emitting unit. Those skilled in the art will understand that the light-emitting layer material is a mixture comprising a solute and a solvent. The solute is an organic electroluminescent material, and the solvent is, for example, propylene glycol monomethyl ether acetate (PGMEA). Therefore, in some examples, the first lyophilic material has a strong attraction to the solvent, such as propylene glycol monomethyl ether acetate (PGMEA), constituting the light-emitting layer material.

[0112] Exemplarily, the contact angle of the first lyophilic material is less than 10°. It should be noted that the "contact angle" refers to the angle between the solid-liquid interface and is a measure of wettability. If the contact angle between the solid material and water is greater than 90°, it indicates that the solid material is a lyophobic material, and the larger the contact angle between the solid material and water, the better the lyophobic property. If the contact angle between the solid material and water is less than 90°, it indicates that the solid material is a lyophilic material, and the smaller the contact angle between the solid material and water, the better the lyophilic property.

[0113] On this basis, when the contact angle between the solid material and water is greater than 90°, the contact angle between the solid material and the light-emitting layer material is greater than 40°; when the contact angle between the solid material and water is less than 90°, the contact angle between the solid material and the light-emitting layer material is less than 10°.

[0114] Based on this, in an embodiment of the present disclosure, the contact angle between the first lyophilic material and the light-emitting layer material is less than 10°, and the first lyophilic material has lyophilic properties to the light-emitting layer material.

[0115] In some embodiments, as shown in Figures 8 and 9, the second retaining wall 14 includes a first material layer 141 and a second material layer 142 that are sequentially away from the substrate 11, the material of the first material layer 141 includes a second lyophilic material, and the material of the second material layer 142 includes a lyophobic material; wherein the second lyophilic material has lyophilic properties to the light-emitting layer material; and the lyophobic material has lyophobic properties to the light-emitting layer material.

[0116] In some examples, the second lyophilic material has a strong attraction to the solvent in the light-emitting layer material, such as propylene glycol monomethyl ether acetate (PGMEA). Meanwhile, the lyophobic material has a strong repulsive force with the light-emitting layer material. Therefore, the lyophobic material has a strong repulsive force with the solvent in the light-emitting layer material, such as propylene glycol monomethyl ether acetate (PGMEA).

[0117] Exemplarily, the contact angle of the second lyophilic material is less than 10°, that is, the contact angle between the second lyophilic material and the light-emitting layer material is less than 10°, and the second lyophilic material has lyophilic properties to the light-emitting layer material.

[0118] Exemplarily, the contact angle of the lyophobic material is greater than 40°, that is, the contact angle between the lyophobic material and the light-emitting layer material is greater than 40°, and the lyophobic material has lyophobic properties with respect to the light-emitting layer material.

[0119] By setting the material of the first retaining wall 13 to include a first lyophilic material and the first material layer 141 of the second retaining wall 14 to include a second lyophilic material, the lower parts of the first retaining wall 13 and the second retaining wall 14 have a strong attraction to the luminescent layer material. When the ink flows into the opening 15 to form the luminescent layer material, the luminescent layer material can be evenly spread over the entire opening 15, which is beneficial to the flatness of the functional layer 30 in the opening 15.

[0120] Moreover, the second material layer 142 formed by the second retaining wall 14 is a liquid-repellent material, and the liquid-repellent material has liquid-repellent properties towards the light-emitting layer material, so that the upper part of the second retaining wall 14 can have a repelling effect on the light-emitting layer material, so that the ink splashed onto the upper part of the second retaining wall 14 can quickly flow down into the opening 15.

[0121] In some embodiments, as shown in FIG. 8 and FIG. 9 , the first lyophilic material and the second lyophilic material are the same.

[0122] In this way, the first material layer 141 of the first retaining wall 13 and the second retaining wall 14 can be formed by the same film forming process, which is conducive to simplifying the process flow.

[0123] In some embodiments, as shown in FIG. 8 and FIG. 9 , a height h2 a of the first material layer 141 is greater than a height h2 b of the second material layer 142 .

[0124] It should be noted that the height h2a of the first material layer 141 refers to the height h2a of the first material layer 141 where the second retaining wall 14 does not cover the first retaining wall 13, and the height h2b of the second material layer 142 refers to the height h2b of the second material layer 142 where the second retaining wall 14 does not cover the first retaining wall 13.

[0125] Exemplarily, the ratio of the height h2a of the first material layer 141 to the height h2b of the second material layer 142 ranges from 4 to 19. For example, the ratio of the height h2a of the first material layer 141 to the height h2b of the second material layer 142 is 4, 5, 7, 9, 10, 12, 14, 16, 18 or 19, etc., which is not limited here.

[0126] Exemplarily, the height h2a of the first material layer 141 ranges from 0.8 μm to 1.9 μm, for example, 0.8 μm, 1 μm, 1.2 μm, 1.4 μm, 1.6 μm, 1.7 μm, or 1.9 μm, etc., and is not limited thereto. The height h2b of the second material layer 142 ranges from 0.1 μm to 0.2 μm, for example, 0.1 μm, 0.15 μm, or 0.2 μm, etc., and is not limited thereto.

[0127] By setting the height h2b of the second material layer 142 to be in the range of 0.1 μm to 0.2 μm and using a liquid-repellent material, ink splashed onto the upper portion of the second retaining wall 14 can quickly flow down into the opening 15 .

[0128] In some embodiments, as shown in FIG. 9 , a height h2 a of the first material layer 141 is greater than or equal to a height h1 of the first retaining wall 13 .

[0129] Exemplarily, as shown in FIG. 9 , a height h2a of the first material layer 141 is greater than a height h1 of the first retaining wall 13 .

[0130] In some other examples, the height h2a of the first material layer 141 is equal to the height h1 of the first retaining wall 13 .

[0131] By setting the height h2a of the first material layer 141 to be greater than or equal to the height h1 of the first retaining wall 13, it can be effectively ensured that the height h2 of the second retaining wall 14 is greater than the maximum height h1a of the first retaining wall h1, and can effectively prevent the cross-color caused by the mutual flow of the light-emitting layer materials between the openings 15 of adjacent rows, thereby improving the display effect of the display device 1000.

[0132] In some embodiments, as shown in FIGS. 10 and 11, the first barrier 13 includes: a plurality of barrier portions 13a arranged in sequence along the first direction Y, and a first gap 16 is provided between every two adjacent barrier portions 13a among the plurality of barrier portions 13a. In the orthographic projection onto the substrate 11, the first gap 13a is located within the second barrier 14, and a part of the second barrier 14 is filled within the first gap 13a.

[0133] It should be noted that FIGS. 8 and 10 are cross-sectional views obtained along the cross-section lines of two structures of the display substrate 10 respectively, and the positions of the cross-section lines corresponding to FIGS. 8 and 10 in the display substrate 10 are the same as the position of the cross-section line FF in the display substrate 10 shown in FIG. 6.

[0134] Exemplarily, as shown in FIGS. 10 and 11, along the first direction Y, the first barrier 13 is not a continuous strip-shaped barrier, but a multi-segmented barrier formed by arranging a plurality of barrier portions 13a in sequence. Moreover, the second barrier 14 covers the first gap 16 and covers some of the barrier portions 13a on both sides of the first gap 16.

[0135] The second barrier 14 covering some of the barrier portions 13a on both sides of the first gap 16 can achieve a better connection between the second barrier 14 and the first barrier 13 to enclose an opening 15.

[0136] As can be seen from the above, as shown in FIG. 9, due to the influence of the film-forming process, the first type of height h21 of the second barrier 14 is less than the second type of height h22, that is, h21 < h22. Therefore, at the intersection of the first barrier 13 and the second barrier 14, due to the presence of the first barrier 13, to a certain extent, it will affect the flatness of the surface of the second barrier 14 away from the substrate 11. Therefore, setting the first barrier 13 as a plurality of barrier portions 13a can reduce the overlapping area between the second barrier 14 and the first barrier 13 and avoid the influence of the first barrier 13 on the flatness of the surface of the second barrier 14 away from the substrate 11.

[0137] In other examples, as shown in FIG. 12, the first barrier 13 is a strip-shaped barrier extending along the first direction Y. This can achieve a better connection between the second barrier 14 and the first barrier 13 to enclose an opening 15.

[0138] In some embodiments, as shown in FIG. 6, the maximum value of the dimension d3 of the first barrier 13 in the second direction X is greater than the dimension d4 of the second barrier 14 in the first direction Y.

[0139] Typically, in an orthographic projection onto the substrate 11, vias are formed in the coverage area of ​​the first retaining wall 13 to connect the functional layer 30 (as shown in FIG. 4 ) formed by the opening 15 with a pixel driving circuit (not shown). For example, as shown in FIG. 13 and FIG. 14 , the functional layer 30 (as shown in FIG. 4 ) is connected to the anode layer 17, and the anode layer 17 is connected to the pixel driving circuit (not shown) via vias provided under the coverage area of ​​the first retaining wall 13, so that the pixel driving circuit drives the display substrate 10 for display. Providing the vias in the coverage area of ​​the first retaining wall 13 rather than in the area covered by the opening 15 is beneficial for maintaining the flatness of the functional layer 30 in the opening 15.

[0140] Moreover, as shown in Figures 2 and 6, the maximum value of the dimension d3 of the first retaining wall 13 in the second direction X is set to be greater than the dimension d4 of the second retaining wall 14 in the first direction Y. This can ensure that the length of a pixel PP in the first direction Y is equal to the length in the second direction X. In other words, the shape of the orthographic projection of a pixel PP on the substrate 11 is a square, thereby effectively preventing the image displayed by the display device 1000 from being deformed or the displayed image from being proportionally inconsistent.

[0141] It should be noted that the pixels PP of the display substrate 10 shown in FIG. 2 and FIG. 6 are not shown to be square. The drawings are merely examples of the arrangement of the pixels PP and do not limit the shape of the pixels PP.

[0142] 13 and 14 , the anode layer 17 is disposed between the substrate 11 and the pixel defining layer 12 . The anode layer 17 includes a plurality of anode patterns 171 , which are disposed in a one-to-one correspondence with the plurality of openings 15 .

[0143] It should be noted that “one-to-one correspondence” means that, in the orthographic projection onto the substrate 11 , one anode pattern 171 overlaps with one opening 15 .

[0144] Along the first direction Y, a second space 181 is defined between every two adjacent anode patterns 171 among the plurality of anode patterns 171, and a portion of the second retaining wall 14 fills the second space 181. Along the second direction X, a third space 182 is defined between every two adjacent anode patterns 171 among the plurality of anode patterns 171, and a portion of the first retaining wall 13 fills the third space 182. In an orthographic projection onto the substrate 11, the maximum height h1a of the first retaining wall 13 is located within the third space 182.

[0145] For example, as shown in Figures 13 and 14, the portion of the second retaining wall 14 filled in the second interval 181 and the portion 19 of the first retaining wall 13 filled in the third interval 182 can further separate the adjacent anode patterns 171, and the portion of the second retaining wall 14 filled in the second interval 181 and the portion 19 of the first retaining wall 13 filled in the third interval 182 cover the side of the anode pattern 171, which can effectively prevent short circuits caused by burr discharge on the side of the anode pattern 171.

[0146] In some examples, in an orthographic projection onto the substrate 11 , the maximum height h1a of the first barrier wall 13 is located within the third space 182 .

[0147] For example, as shown in FIG14 , along the second direction X, from left to right, there are first retaining wall 131, first retaining wall 132, and first retaining wall 133, as well as anode pattern 171a, anode pattern 171b, anode pattern 171c, and anode pattern 171d of anode layer 17. In an orthographic projection onto substrate 11, the maximum height h1a of first retaining wall 131 is located at third interval 182 between anode pattern 171a and anode pattern 171b, the maximum height h1a of first retaining wall 132 is located at third interval 182 between anode pattern 171b and anode pattern 171c, and the maximum height h1a of first retaining wall 133 is located at third interval 182 between anode pattern 171c and anode pattern 171d.

[0148] From the above introduction about the first retaining wall 13, it can be seen that since the height h1 of the first retaining wall 13 gradually increases and then gradually decreases, the setting of the maximum height h1a of the first retaining wall 13 being located within the third interval 182 in the positive projection onto the substrate 11 can effectively ensure that the material forming the first retaining wall 13 can be effectively filled in the third interval 182, thereby effectively preventing short circuits caused by burr discharge on the side of the anode pattern 171.

[0149] An embodiment of the present disclosure further provides a method for preparing a display substrate, as shown in FIG15 , the method includes steps: R1 and R2.

[0150] R1. As shown in FIG16 , a substrate 11 is formed.

[0151] For the introduction of the substrate 11 , please refer to the above content and will not be repeated here.

[0152] R2. As shown in FIG16 , a pixel defining layer 12 is formed on one side of the substrate 11. The step of forming the pixel defining layer 12 includes forming a plurality of first retaining walls 13, wherein the plurality of first retaining walls 13 extend along a first direction Y. A plurality of second retaining walls 14 are formed on a side of the plurality of first retaining walls 13 away from the substrate 11, wherein the plurality of second retaining walls 14 extend along a second direction X, where the first direction Y and the second direction X intersect.

[0153] The plurality of first retaining walls 13 and the plurality of second retaining walls 14 are connected to form a plurality of openings 15; the plurality of light-emitting units are positioned in a one-to-one correspondence within the plurality of openings 15. Furthermore, along the second direction X, the height h1 of the first retaining walls 13 gradually increases and then gradually decreases, with the height h1 being perpendicular to the substrate 11.

[0154] For the introduction of the first retaining wall 13 , the second retaining wall 14 and the opening 15 , please refer to the above content and will not be repeated here.

[0155] For example, gradient exposure is used to form the first retaining wall 13 with a height h1 that gradually increases and then gradually decreases. Gradient exposure means controlling the exposure intensity or exposure time to change gradually during the exposure process, thereby forming the first retaining wall 13 with a curved or inclined surface.

[0156] As shown in FIG. 6 and FIG. 17 , the method for preparing the display substrate further includes: coating ink in the opening 15 to form a functional layer 30 .

[0157] The process of coating ink in the opening 15 to form the functional layer 30 includes: operating the coating device 200 to coat the ink in the opening 15 along the second direction X.

[0158] For example, as shown in Figures 6 and 17 , ink is applied using a slit coating technique. A nozzle 201 of a coating device 200 is positioned between each pair of adjacent second retaining walls 14 . The nozzle 201 moves between the two adjacent second retaining walls 14 along the second direction X. In other words, the nozzle 201 moves in the transverse direction. During this process, the nozzle 201 applies ink to a row of openings 15 between the two adjacent second retaining walls 14 . The applied ink forms the luminescent layer material, which is used to form the functional layer 30 .

[0159] It should be noted that, as shown in Figure 17, the nozzle 201 applies ink to a row of openings 15 between two adjacent second retaining walls 14, first forming an initial functional layer 301. After the initial functional layer 301 is dried and other processing processes, a functional layer 30 located in the opening 15 is obtained.

[0160] Since the surface of the first retaining wall 13 is a sloped surface N, when the nozzle 201 moves along the second direction X during ink coating, the sloped surface N of the first retaining wall 13 can reduce the blocking effect of the first retaining wall 13 on the ink, reduce the accumulation degree of the light-emitting layer material at the edge of the first retaining wall 13, and slow down the climbing degree of the light-emitting layer material at the first retaining wall 13, which can effectively improve the flatness of the functional layer 30 of the sub-pixel P, and further improve the uniformity of the functional layer 30 of the sub-pixel P, thereby improving the display effect of the display device 1000.

[0161] In some embodiments, as shown in FIG. 6 , FIG. 7 and FIG. 17 , the coating device 200 coats ink in the opening 15 along a direction from the second slope angle α2 of the first retaining wall 13 to the first slope angle α1 of the first retaining wall 13 .

[0162] As can be seen from the above, as shown in Figure 7, the first slope angle α1 is closer to the highest point L2 of the first retaining wall 13 than the second slope angle α2, resulting in a second sloped surface N2 with a gentler slope. Furthermore, the ink-blocking effect of the sloped surface N with a smaller slope angle is less than that of the sloped surface N with a larger slope angle.

[0163] Therefore, when the coating device 200 coats ink in the opening 15 of the display substrate 10 along the direction from the second slope angle α2 of the first retaining wall 13 to the first slope angle α1 of the first retaining wall 13, the second slope surface N2 can further reduce the blocking effect of the first retaining wall 13 on the ink, effectively improve the flatness of the functional layer 30 of the sub-pixel P, and improve the display effect of the display device 1000.

[0164] As shown in FIG1 , some embodiments of the present disclosure provide a display device 1000 , which includes a display substrate 10 as described in any of the above embodiments, and a driver chip for driving the display substrate 10 for display.

[0165] The display device may be, for example, a mobile phone, a tablet computer, a personal digital assistant (PDA), an in-vehicle computer, a wearable display device, or the like. The embodiments of the present disclosure do not impose any particular restrictions on the specific form of the above-mentioned display device. The display device 1000 includes the display substrate 10 provided in any of the above-mentioned embodiments. Therefore, the display device 1000 provided in the embodiments of the present disclosure has all the beneficial effects of the display substrate 10 provided in any of the above-mentioned embodiments, which will not be further described here.

[0166] The above description is merely a specific embodiment of the present disclosure, but the scope of protection of the present disclosure is not limited thereto. Any changes or substitutions that a person skilled in the art can conceive within the technical scope disclosed in the present disclosure should be included within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be based on the scope of protection of the claims.

Claims

1. A display substrate, comprising: substrate; A pixel defining layer is located on one side of the substrate; the pixel defining layer includes a plurality of first retaining walls and a plurality of second retaining walls; The plurality of first retaining walls extend along a first direction, the plurality of second retaining walls extend along a second direction, and the first direction and the second direction intersect; The plurality of first retaining walls and the plurality of second retaining walls are connected and enclosed to form a plurality of openings, and the plurality of light emitting units are located in the plurality of openings in a one-to-one correspondence; Along the second direction, the height of each of the plurality of first retaining walls gradually increases and then gradually decreases, and the direction of the height is perpendicular to the substrate.

2. The display substrate according to claim 1, wherein In any cross section of the first barrier wall perpendicular to the substrate, along the second direction, portions of the first barrier wall located on opposite sides of the highest position thereof have different height change rates.

3. The display substrate according to claim 2, wherein: In the longitudinal section of the first retaining wall, an angle formed between the first retaining wall and the plane where the substrate is located includes: a first slope angle and a second slope angle, the angle of the first slope angle is greater than the angle of the second slope angle, and the longitudinal section of the first retaining wall is perpendicular to the substrate and perpendicular to the first direction.

4. The display substrate according to claim 3, wherein: The angle difference between the first slope angle and the second slope angle ranges from 5° to 65°.

5. The display substrate according to claim 3 or 4, wherein: The first slope angle ranges from 35° to 70°; The second slope angle ranges from 5° to 30°.

6. The display substrate according to any one of claims 1 to 5, wherein: The maximum height of the first retaining wall is less than or equal to 1 μm and greater than or equal to 0.5 μm.

7. The display substrate according to any one of claims 1 to 6, wherein: The height of the second retaining wall is greater than the maximum height of the first retaining wall.

8. The display substrate according to claim 7, wherein: The height of the second retaining wall ranges from 1 μm to 2 μm.

9. The display substrate according to any one of claims 1 to 8, wherein: The first retaining wall comprises: a plurality of retaining wall portions sequentially arranged along the first direction, wherein a first interval is formed between each two adjacent retaining wall portions of the plurality of retaining wall portions; In an orthographic projection onto the substrate, the first space is located within the second retaining wall; a portion of the second retaining wall fills the first space.

10. The display substrate according to any one of claims 1 to 9, wherein: The material of the first retaining wall includes a first lyophilic material; The second retaining wall includes a first material layer and a second material layer that are sequentially away from the substrate, wherein the material of the first material layer includes a second lyophilic material, and the material of the second material layer includes a lyophobic material; The first lyophilic material and the second lyophilic material have lyophilic properties to the light-emitting layer material in the light-emitting unit; and the lyophobic material has lyophobic properties to the light-emitting layer material.

11. The display substrate according to claim 10, wherein: The first lyophilic material and the second lyophilic material are the same.

12. The display substrate according to claim 10 or 11, wherein: The height of the first material layer is greater than that of the second material layer.

13. The display substrate according to any one of claims 10 to 12, wherein: The height of the first material layer is greater than or equal to the height of the first retaining wall.

14. The display substrate according to any one of claims 1 to 13, wherein: The maximum value of the dimension of the first retaining wall in the second direction is greater than the dimension of the second retaining wall in the first direction.

15. The display substrate according to any one of claims 1 to 14, further comprising: an anode layer disposed between the substrate and the pixel defining layer; the anode layer comprising a plurality of anode patterns, the plurality of anode patterns being disposed in one-to-one correspondence with the plurality of openings; Wherein, along the first direction, there is a second gap between every two adjacent anode patterns among the plurality of anode patterns, and a portion of the second retaining wall is filled in the second gap; Along the second direction, there is a third interval between each two adjacent anode patterns among the multiple anode patterns, and a portion of the first retaining wall fills the third interval; and in the orthographic projection onto the substrate, the maximum height of the first retaining wall is located within the third interval.

16. A method for preparing a display substrate, comprising: forming a substrate; forming a pixel defining layer on one side of the substrate; Wherein, forming a pixel defining layer on one side of the substrate includes: forming a plurality of first retaining walls, the plurality of first retaining walls extending along a first direction; along a second direction, the height of each of the plurality of first retaining walls gradually increases and then gradually decreases, the direction in which the height is located is perpendicular to the substrate, and the first direction and the second direction intersect; A plurality of second retaining walls are formed on a side of the plurality of first retaining walls away from the substrate, and the plurality of second retaining walls extend along the second direction; the plurality of first retaining walls and the plurality of second retaining walls are connected to form a plurality of openings; and a plurality of light-emitting units are located in the plurality of openings in a one-to-one correspondence.

17. The method for preparing a display substrate according to claim 16, further comprising: Applying ink in the opening to form a functional layer; Wherein, the step of applying ink in the opening to form a functional layer comprises: The coating device coats ink in the opening along the second direction to obtain a functional layer.

18. The method for preparing a display substrate according to claim 17, wherein: The step of applying ink in the opening comprises applying ink in the opening by a coating device along a direction from the second slope angle of the first retaining wall to the first slope angle of the first retaining wall; wherein the first slope angle is greater than the second slope angle.

19. A display device comprising: The display substrate according to any one of claims 1 to 15; The driving chip is used to drive the display substrate to perform display.

Images