Display substrate and display device

Abstract

The invention provides a display substrate and a display device. The display substrate comprises a substrate; the pixel definition layer and the light-emitting devices are arranged on one side of the substrate, the pixel definition layer comprises a plurality of pixel openings, the light-emitting devices correspond to the pixel openings in a one-to-one mode, at least parts of the light-emitting devices are located in the pixel openings, and each light-emitting device comprises an anode layer, a light-emitting layer and a cathode layer which are sequentially arranged in the first direction; the plurality of isolation columns are arranged on one side, far away from the substrate, of the pixel definition layer, the isolation columns are arranged around the pixel openings so as to separate the light-emitting layers of any two adjacent light-emitting devices, and each isolation column comprises a conductor structure and an inorganic material layer which are sequentially arranged in the first direction; the auxiliary electrode layer is arranged on one side, far away from the substrate, of the cathode layer; the cathode layer and the auxiliary electrode layer are electrically connected with the conductor structure. According to the technical scheme, the problem that the display device is uneven in light emitting can be effectively solved.

Description

Technical Field

[0001] This application relates to the field of display device technology, and more specifically, to a display substrate and a display device. Background Technology

[0002] Organic light-emitting diodes (OLEDs) have the characteristics of high color gamut, high contrast, flexible self-illumination, and low power consumption, and are one of the mainstream information display technologies currently used in smart display ports.

[0003] Existing OLED devices typically consist of an anode layer, a light-emitting layer, and a cathode layer. Based on the different light-emitting surfaces, they can be divided into bottom-emitting and top-emitting types. Top-emitting devices have become a research hotspot in recent years because they can achieve a larger aperture ratio. Top-emitting OLEDs require a thin cathode and a reflective anode to increase light transmittance. However, thin transparent cathodes generally suffer from high resistance and significant voltage drop. The voltage drop is more pronounced the farther the OLED light-emitting surface is from the power supply location, resulting in noticeable uneven light emission in the OLED device. Summary of the Invention

[0004] In view of the above problems, this application provides a display substrate and a display device, which can effectively improve the problem of uneven light emission in the display device.

[0005] In a first aspect, a display substrate is provided, comprising: a substrate; a pixel definition layer and a plurality of light-emitting devices disposed on one side of the substrate, the pixel definition layer including a plurality of pixel openings, the plurality of light-emitting devices corresponding one-to-one with the plurality of pixel openings, at least a portion of the light-emitting devices being located within the pixel openings, the light-emitting devices including an anode layer, a light-emitting layer and a cathode layer disposed sequentially along a first direction, the first direction being the thickness direction of the display substrate; a plurality of isolation pillars disposed on the side of the pixel definition layer away from the substrate, the isolation pillars being disposed around the pixel openings to separate the light-emitting layers of any two adjacent light-emitting devices, the isolation pillars including a conductive structure and an inorganic material layer disposed sequentially along the first direction; and an auxiliary electrode layer disposed on the side of the cathode layer away from the substrate; wherein the cathode layer and the auxiliary electrode layer are electrically connected to the conductive structure respectively.

[0006] In conjunction with the first aspect, in some implementations of the first aspect, the inorganic material layer extends beyond the conductive structure at both ends in the second direction, and the second direction is perpendicular to the first direction.

[0007] In conjunction with the first aspect, in some implementations of the first aspect, the display substrate further includes a cover layer disposed on the side of the cathode layer away from the substrate, or the cover layer disposed on the side of the auxiliary electrode layer away from the substrate.

[0008] In conjunction with the first aspect, in some implementations of the first aspect, the refractive index of the capping layer is greater than the refractive index of the auxiliary electrode layer.

[0009] In conjunction with the first aspect, in some implementations of the first aspect, the orthographic projection of the cover layer on the substrate lies within the orthographic projection of the auxiliary electrode layer on the substrate.

[0010] In conjunction with the first aspect, in some implementations of the first aspect, the light-emitting device further includes a first functional layer and a second functional layer, wherein the anode layer, the first functional layer, the light-emitting layer, the second functional layer and the cathode layer are arranged sequentially along the first direction, wherein the cathode layer covers the side of the second functional layer away from the substrate and the side of the second functional layer, and the direction in which the side of the second functional layer is located intersects with the second direction.

[0011] In conjunction with the first aspect, in some implementations of the first aspect, the cathode layer includes a first groove, and the auxiliary electrode layer includes a first portion disposed on the side of the cathode layer away from the substrate and a second portion located within the first groove, the first portion and the second portion being connected.

[0012] In conjunction with the first aspect, in some implementations of the first aspect, the display substrate further includes an encapsulation layer disposed on the side of the auxiliary electrode layer away from the substrate. The auxiliary electrode layer includes a second groove, the orthographic projection of the second groove on the substrate being located within the orthographic projection of the first groove on the substrate, and a portion of the encapsulation layer filling the second groove.

[0013] In conjunction with the first aspect, in some implementations of the first aspect, the material of the auxiliary electrode layer includes at least one selected from Yb, Bi, Co, Mo, Ti, Zr, Al, Cr, Nb, Pt, W, In, Sn, Fe, Ni, Ta, Mn, Zn, and Ge.

[0014] In conjunction with the first aspect, in some implementations of the first aspect, the material of the capping layer includes at least one of carbocyclic compounds, heterocyclic compounds, amino-containing compounds, porphyrin derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalene phthalocyanine derivatives, alkali metal complexes, and alkaline earth metal complexes.

[0015] In a second aspect, a display device is provided, comprising a display substrate as described in any possible implementation of the first aspect above. Attached Figure Description

[0016] Figure 1 This is a schematic structural diagram of a display substrate disclosed in an embodiment of this application;

[0017] Figure 2 This is a schematic structural diagram of a display substrate disclosed in an embodiment of this application;

[0018] Figure 3 This is a schematic structural diagram of a display substrate disclosed in an embodiment of this application. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0020] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B; the term "and / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone.

[0021] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, in the description of this embodiment, unless otherwise stated, "a plurality of" means two or more.

[0022] References to "one embodiment" or "some embodiments" in the embodiments described in this application mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0023] Organic light-emitting diodes (OLEDs) have the characteristics of high color gamut, high contrast, flexible self-illumination, and low power consumption, and are one of the mainstream information display technologies currently used in smart display ports.

[0024] Existing OLED devices typically consist of an anode layer, a light-emitting layer, and a cathode layer. Based on the different light-emitting surfaces, they can be divided into bottom-emitting and top-emitting types. Top-emitting devices have become a research hotspot in recent years because they can achieve a larger aperture ratio. Top-emitting OLEDs require a thin cathode and a reflective anode to increase light transmittance. However, thin transparent cathodes generally suffer from high resistance and significant voltage drop. The voltage drop is more pronounced the farther the OLED light-emitting surface is from the power supply location, resulting in noticeable uneven light emission in the OLED device.

[0025] In view of this, embodiments of this application provide a display substrate and a display device. Specifically, a pixel definition layer and a plurality of light-emitting devices are disposed on one side of the substrate. The pixel definition layer includes a plurality of pixel openings, and the plurality of light-emitting devices correspond one-to-one with the plurality of pixel openings. At least a portion of the light-emitting devices is located within the pixel openings. Each light-emitting device includes an anode layer, a light-emitting layer, and a cathode layer sequentially disposed along a first direction. A plurality of isolation pillars are disposed on the side of the pixel definition layer away from the substrate. The isolation pillars are disposed around the pixel openings to separate the light-emitting layers of any two adjacent light-emitting devices. Each isolation pillar includes a conductive structure and an inorganic material layer sequentially disposed along the first direction. An auxiliary electrode layer is disposed on the side of the cathode layer away from the substrate, and the cathode layer and the auxiliary electrode layer are electrically connected to the conductive structure, respectively. In the technical solution of this application embodiment, by electrically connecting both the cathode layer and the auxiliary electrode layer to the conductive structure, the cathode layer and the auxiliary electrode layer are connected in parallel, thereby reducing the resistance of the cathode layer, which is beneficial to improving the voltage drop problem of the cathode layer, thereby effectively improving the problem of uneven light emission in the display device.

[0026] The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0027] Figure 1 This is a schematic structural diagram of a display substrate provided in an embodiment of this application.

[0028] like Figure 1 As shown, the display substrate 10 includes a substrate 11, a pixel definition layer 12, multiple light-emitting devices 13, multiple isolation pillars 14, and an auxiliary electrode layer 15.

[0029] Specifically, a pixel definition layer 12 is disposed on the substrate 11. The pixel definition layer 12 has a plurality of pixel openings, and a plurality of light-emitting devices 13 correspond one-to-one with the plurality of pixel openings. At least a portion of the light-emitting device 13 is located within the pixel opening. The light-emitting device 13 includes an anode layer 131, a light-emitting layer 132, and a cathode layer 133 sequentially disposed along a first direction. The first direction is the thickness direction of the display substrate 10. For example, as shown in the figure... Figure 1 As shown, the thickness direction of the display substrate 10 is the x-direction.

[0030] It should be understood that the x-direction is merely an exemplary description of the thickness direction of the display substrate 10 and does not constitute a limitation on the thickness direction of the display substrate 10 in this application. The y-direction is merely an exemplary description of a first direction and does not constitute a limitation on the first direction in this application. For ease of description, the following description will use the thickness direction of the display substrate 10 as the x-direction.

[0031] It should be noted that, in this embodiment, the pixel opening of the pixel definition layer 12 extends through the opening of the pixel definition layer 12 in the first direction x. In other words, the pixel opening makes the pixel definition layer 12 discontinuous in the second direction. The second direction is perpendicular to the x-direction, for example, as... Figure 1 The y-direction shown below will be referred to as the second direction for ease of description.

[0032] In the embodiments of this application, the area where the pixel opening is set can be called a sub-pixel area, which may include a first sub-pixel area, such as the R pixel area; a second sub-pixel area, such as the G pixel area; a third sub-pixel area, such as the B pixel area, etc.

[0033] Light-emitting devices 13 are disposed within pixel openings, with one type of light-emitting device 13 disposed within each pixel opening. These light-emitting devices 13 constitute a sub-pixel of the display substrate 10. The pixel definition layer 12 includes multiple pixel openings, and different types of light-emitting devices 13 can be disposed within different pixel openings to achieve full-color display of the display device. For example, a red-emitting light-emitting device 13 can be disposed within the first pixel opening, a green-emitting light-emitting device 13 within the second pixel opening, and a blue-emitting light-emitting device 13 within the third pixel opening, etc.

[0034] like Figure 1 As shown, a plurality of isolation pillars 14 are provided on the side of the pixel definition layer 12 away from the substrate 11. The isolation pillars 14 are arranged around the pixel opening to separate the light-emitting layers 132 of any two adjacent light-emitting devices 13. The isolation pillars 14 include a conductive structure 141 and an inorganic material layer 142 arranged sequentially along the x-direction. An auxiliary electrode layer 15 is provided on the side of the cathode layer 133 away from the substrate 11, and both the cathode layer 133 and the auxiliary electrode layer 15 are electrically connected to the conductive structure 141.

[0035] It should be noted that, in this embodiment, the film layers of the light-emitting devices 13 are formed by full-surface vapor deposition during the fabrication of the display substrate 10. Therefore, during the fabrication of the display substrate 10, after forming the anode layer 131 and the pixel definition layer 12, isolation pillars 14 are provided on the pixel definition layer 12, and the isolation pillars 14 are arranged around the pixel openings. In this way, during full-surface vapor deposition, the height difference between the isolation pillars 14 and the pixel openings is used to separate the light-emitting layers 132 of each light-emitting device 13. That is, when the light-emitting material is vapor-deposited, a continuous light-emitting layer 132 is not formed in the y-direction, but rather multiple light-emitting layers 132 are formed, each located within a multiple pixel opening. The fabrication process of the display substrate 10 provided in this embodiment will be described in detail below regarding the fabrication method of the display substrate 10.

[0036] In this embodiment, by providing a conductive structure 141 on the side of the pixel definition layer 12 away from the substrate 11 and an auxiliary electrode layer 15 on the side of the cathode layer 133 away from the substrate 11, and by providing the cathode layer 133 and the auxiliary electrode layer 15 to be electrically connected to the conductive structure 141 respectively, the cathode layer 133 and the auxiliary electrode layer 15 are connected in parallel, thereby reducing the resistance of the cathode layer 133, which is beneficial to improving the voltage drop problem of the cathode layer 133, and thus effectively improving the problem of uneven light emission in the display device.

[0037] It should be noted that in this embodiment, the light-emitting side of the OLED is located on the side of the light-emitting layer 132 away from the substrate 11, that is, the OLED is a top-emitting structure, and the material of the anode layer 131 is a reflective material.

[0038] In some embodiments, the anode layer 131 may be made of a reflective material, such as an ITO / Ag / ITO stacked structure.

[0039] Exemplarily, the substrate 11 can be a flexible substrate, and the substrate 11 can be a multilayer structure. Specifically, the substrate 11 may include a base layer, a barrier layer, and a buffer layer. The material of the base layer may include at least one selected from polyimide, polyethylene terephthalate, and polycarbonate.

[0040] In some embodiments, a pixel circuit layer may be disposed between the substrate 11 and the pixel definition layer 12. This pixel circuit layer may include a thin-film transistor and a capacitor. The thin-film transistor includes an active layer, a gate electrode, a source electrode, and a drain electrode. The capacitor includes a first electrode and a second electrode.

[0041] For example, the pixel circuit layer includes multiple sub-pixels arranged in an array, multiple gate lines, and multiple data lines. Each sub-pixel includes a light-emitting element and a pixel circuit driving the light-emitting element. The multiple gate lines and multiple data lines intersect each other to define multiple pixel regions arranged in an array in the display area, and a pixel circuit for one sub-pixel is disposed in each pixel region. This pixel circuit is, for example, a conventional pixel circuit, such as a 2T1C (i.e., two transistors and one capacitor) pixel circuit, a 4T2C, 5T1C, 7T1C, etc. nTmC (n, m are positive integers) pixel circuit, and in different embodiments, the pixel circuit may further include a compensation sub-circuit, which may include an internal compensation sub-circuit or an external compensation sub-circuit, and the compensation sub-circuit may include transistors, capacitors, etc. For example, as needed, the pixel circuit may further include a reset circuit, a light-emitting control sub-circuit, a detection circuit, etc. For example, the pixel circuit layer may also include a gate driving sub-circuit and a data driving sub-circuit located in the non-display area. The gate driving sub-circuit is connected to the pixel circuit via gate lines to provide various scan signals, and the data driving sub-circuit is connected to the pixel circuit via data lines to provide data signals.

[0042] In some embodiments, such as Figures 1 to 3 As shown, the two ends of the inorganic material layer 142 in the y direction extend beyond the two ends of the conductive structure 141 in the y direction.

[0043] The isolation pillar 14 forms an "eaves" structure through the above-mentioned structural arrangement, which further ensures that the isolation pillar 14 can separate the light-emitting layers 132 in different pixel openings.

[0044] In some embodiments, such as Figure 2 and Figure 3 As shown, the display substrate 10 also includes a cover layer 16.

[0045] Specifically, such as Figure 2 As shown, the capping layer 16 is disposed on the side of the cathode layer 133 away from the substrate 11, or as... Figure 3 As shown, the cover layer 16 is disposed on the side of the auxiliary electrode layer 15 away from the substrate 11.

[0046] In some embodiments, the refractive index of the capping layer 16 is greater than the refractive index of the auxiliary electrode layer 15. For example, the refractive index of the capping layer 16 may be greater than or equal to 1.6, and the refractive index of the auxiliary electrode layer 15 may be less than or equal to 1.

[0047] In this embodiment, the refractive index of the cover layer 16 is greater than that of the auxiliary electrode layer 15, and the two form a coherent destructive structure, which reduces the reflectivity of external light on the display substrate and thus improves the display quality of the display device.

[0048] In some embodiments, the cover layer 16 may include at least one of an organic material cover layer, an inorganic material cover layer, or a mixed material cover layer of organic and inorganic materials.

[0049] Specifically, the material of the capping layer 16 may include at least one of carbocyclic compounds, heterocyclic compounds, amino-containing compounds, porphyrin derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalene phthalocyanine derivatives, alkali metal complexes, and alkaline earth metal complexes.

[0050] The material of the capping layer 16 may also include at least one of the following: carbocyclic compounds, heterocyclic compounds, and amine-containing compounds. For example, it may be substituted with at least one of the following: oxygen, nitrogen, sulfur, selenium, silicon, fluorine, chlorine, bromine, and iodine.

[0051] In some embodiments, the auxiliary electrode layer 15 may include a conductive material, such as a conductive metal material.

[0052] In some embodiments, the material of the auxiliary electrode layer 15 may include at least one of Yb, Bi, Co, Mo, Ti, Zr, Al, Cr, Nb, Pt, W, In, Sn, Fe, Ni, Ta, Mn, Zn, and Ge.

[0053] In some embodiments, such as Figure 2 and Figure 3 As shown, the orthographic projection of the cover layer 16 on the substrate 11 is located inside the orthographic projection of the auxiliary electrode layer 15 on the substrate 11.

[0054] In some embodiments, such as Figure 2 and Figure 3 As shown, the light-emitting device 13 may further include a first functional layer 134 and a second functional layer 135. The anode layer 131, the first functional layer 134, the light-emitting layer 132, the second functional layer 135 and the cathode layer 133 are arranged sequentially along the x-direction. The cathode layer 133 covers the side of the second functional layer 135 away from the substrate 11 and the side of the second functional layer 135. The direction of the side of the second functional layer 135 intersects the y-direction.

[0055] For example, such as Figure 2 and Figure 3 As shown, the side of the second functional layer 135 is perpendicular to the y-direction, meaning the side of the second functional layer 135 is parallel to the x-direction.

[0056] In some embodiments, the first functional layer 134 may include a hole injection layer and a hole transport layer.

[0057] The hole transport layer is used to transport holes, and the material of the hole transport layer may include at least one of aromatic amine hole transport materials, dimethylfluorene hole transport materials, and carbazole hole transport materials.

[0058] The material of the hole injection layer can include p-type dopants with strong electron-withdrawing systems.

[0059] In some embodiments, the second functional layer 135 may include an electron transport layer and an electron injection layer.

[0060] The electron transport layer is used to transport electrons, and the material of the electron transport layer can be a triazine-based material.

[0061] In some embodiments, such as Figure 2 As shown, the cathode layer 133 includes a first groove 1331, and the auxiliary electrode layer 15 includes a first portion 151 disposed on the side of the cathode layer 133 away from the substrate 11 and a second portion 152 located in the first groove 1331. The first portion 151 and the second portion 152 are connected and disposed together.

[0062] In some embodiments, such as Figures 1 to 3 As shown, the display substrate 10 may further include an encapsulation layer 17, which is disposed on the side of the auxiliary electrode layer 15 away from the substrate 11, and the encapsulation layer 17 is continuously disposed in the y direction.

[0063] Exemplarily, in some embodiments, such as Figure 2 As shown, the auxiliary electrode layer 15 includes a second groove 153. The orthographic projection of the second groove 153 on the substrate 11 is located within the orthographic projection of the first groove 1331 on the substrate 11. A portion of the encapsulation layer 17 fills the second groove 153.

[0064] Specifically, the encapsulation layer 17 may include a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer sequentially disposed along the x-direction. (Not shown in the figure)

[0065] In some embodiments, the materials of the first inorganic encapsulation layer and the second inorganic encapsulation layer may include inorganic insulating materials. For example, they may include at least one of silicon oxide, silicon nitride, aluminum oxide, titanium oxide, and silicon oxynitride.

[0066] The materials of the first inorganic encapsulation layer and the second inorganic encapsulation layer can be the same or different. Those skilled in the art can choose according to their needs, and this application does not limit this.

[0067] As described above, the light-emitting device 13 of the display substrate 10 provided in this application embodiment is formed by full-surface vapor deposition. Therefore, when the light-emitting layer 132, cathode layer 133, first functional layer 134, and second functional layer 135 of the light-emitting device 13 are vapor-deposited within the pixel opening, multiple film layers corresponding to the aforementioned film layers of the light-emitting device 13 are also formed on the side of the isolation pillar 14 away from the substrate 11. Furthermore, the auxiliary electrode layer 15, cover layer 16, and other film layers of the display substrate 10 are also formed by full-surface vapor deposition. Therefore, film layers corresponding to the aforementioned auxiliary electrode layer 15, cover layer 16, and other film layers are also formed on the side of the isolation pillar 14 away from the substrate 11. For example, as... Figure 1 As shown, a light-emitting layer 132, a cathode layer 133, and an auxiliary electrode layer 15 are sequentially disposed on the anode layer 131 along the x-direction. Similarly, the side of the isolation pillar 14 furthest from the substrate 11 has a light-emitting layer 132, a cathode layer 133, and an auxiliary electrode layer 15 sequentially stacked along the x-direction. For example, as... Figure 2 As shown, the anode layer 131 is provided with a first functional layer 134, a light-emitting layer 132, a second functional layer 135, a cathode layer 133, a cover layer 16 and an auxiliary electrode layer 15 in sequence along the x direction. The isolation pillar 14 is provided with the first functional layer 134, the light-emitting layer 132, the second functional layer 135, the cathode layer 133, the cover layer 16 and the auxiliary electrode layer 15 in sequence along the x direction on the side away from the substrate 11.

[0068] The film layer on the side of the isolation pillar 14 away from the substrate 11 is formed simultaneously when the light-emitting device 13, the cover layer 16 and the auxiliary electrode layer 15 are formed in the pixel opening. For the specific formation process, please refer to the detailed description of the preparation method of the display substrate provided in the embodiments of this application below.

[0069] The display substrate provided in the embodiments of this application has been described above. The preparation method of the display substrate provided in the embodiments of this application is described below. The parts similar to the display substrate described above will not be repeated.

[0070] For example, with Figure 2 Taking the display substrate 10 shown as an example, the detailed steps of the preparation method of the display substrate 10 provided in the embodiments of this application are explained.

[0071] a) Anode layer: First, indium tin oxide (ITO), silver (Ag), and ITO are deposited sequentially on the substrate to form the first electrode layer. Then, the first electrode layer is subjected to photoresist coating, exposure, development, etching, and photoresist stripping processes to form the anode layer.

[0072] b) Pixel definition layer: First, insulating organic or inorganic materials are deposited on the anode layer and the bare substrate to form a dielectric film. Then, the dielectric film is processed by coating photoresist, exposure, development, etching, and photoresist stripping to form the pixel definition layer.

[0073] c) Sputter conductive film layers onto the pixel definition layer and the anode layer to form the conductive structure to be processed.

[0074] d) Coat the conductive structure to be treated with inorganic material and cure it to form an inorganic material layer.

[0075] e) The conductive structure and inorganic material layer to be processed inside the R pixel opening are removed by exposure, development and etching to expose the evaporation area of ​​the R pixel.

[0076] f) Hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, and auxiliary electrode layer of the R pixel are sequentially vapor-deposited on the anode layer and the inorganic material layer to be processed within the opening of the R pixel. Then, the first inorganic encapsulation layer is formed on the auxiliary electrode layer by vapor deposition.

[0077] g) The conductive structure to be processed and the inorganic material layer to be processed, as well as the hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer and first inorganic encapsulation layer of the R pixel are removed by exposure, development and etching to expose the vapor deposition area of ​​the G pixel.

[0078] h) Hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, and auxiliary electrode layer of the G pixel are sequentially deposited on the anode layer and the first inorganic encapsulation layer inside the G pixel opening. Then, a second inorganic encapsulation layer is formed on the auxiliary electrode layer by vapor deposition.

[0079] i) The conductive structure to be processed and the inorganic material layer to be processed in the opening of the B pixel, as well as the hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, first inorganic encapsulation layer of the R pixel, and the hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, and second inorganic encapsulation layer of the G pixel are removed by exposure, development, and etching to expose the vapor deposition area of ​​the B pixel.

[0080] j) Hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, and auxiliary electrode layer of B pixel are sequentially deposited on the anode layer and the second inorganic encapsulation layer inside the opening of B pixel. Then, a third inorganic encapsulation layer is formed on the auxiliary electrode layer by vapor deposition.

[0081] k) Remove the hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, second inorganic encapsulation layer, and hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, and third inorganic encapsulation layer of the G pixel on the first inorganic encapsulation layer of the R pixel area, as well as the hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, and third inorganic encapsulation layer of the B pixel, by means of exposure, development, and etching.

[0082] l) Remove the hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, and third inorganic encapsulation layer of the B pixel on the second inorganic encapsulation layer of the G pixel area by means of exposure, development, and etching.

[0083] It should be noted that during the fabrication process of the above-mentioned display substrate 10, after all RGB pixels are encapsulated, the R pixel area and G pixel area are exposed, developed, and etched respectively to remove excess film layers and encapsulation layers. The display substrate provided in this application embodiment may also perform exposure, development, and etching processes on the pixel area after forming a pixel to remove excess film layers and encapsulation layers.

[0084] The following describes another method for preparing a display substrate according to an embodiment of this application. Steps a') to d') are the same as those described above, and will not be repeated here.

[0085] e') The conductive structure and inorganic material layer to be processed inside the R / G / B pixel opening are removed by exposure, development and etching, exposing the evaporation area of ​​the R / G / B pixel, and at the same time forming isolation pillars around the R / G / B pixel opening.

[0086] f') Hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, and auxiliary electrode layer of the R pixel are sequentially deposited on the anode layer and the isolation pillar inside the R / G / B pixel opening. Then, the first inorganic encapsulation layer is formed on the auxiliary electrode layer by vapor deposition.

[0087] g') The hole injection layer, hole transport layer, organic light-emitting layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, and first inorganic encapsulation layer of the G pixel area, B pixel area, and R pixel on the isolation pillar are removed by exposure, development, and etching to expose the vapor deposition area and isolation pillar of the G / B pixel.

[0088] h') Hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, and auxiliary electrode layer of G pixel are sequentially deposited on the anode layer inside the G / B pixel opening, the first inorganic encapsulation layer of R pixel area, and the exposed isolation pillar. Then, a second inorganic encapsulation layer is formed on the auxiliary electrode layer by vapor deposition.

[0089] i') The hole injection layer, hole transport layer, organic light-emitting layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, and second inorganic encapsulation layer of the R pixel area, B pixel area, and G pixel on the isolation pillar are removed by exposure, development, and etching to expose the vapor deposition area and isolation pillar of the B pixel.

[0090] j') Hole injection layer, hole transport layer, light emission layer, electron transport layer, electron injection layer, cathode layer, capping layer, and auxiliary electrode layer of B pixel are sequentially vapor-deposited on the anode layer inside the B pixel opening and on the exposed isolation pillar. Then, a third inorganic encapsulation layer is formed on the auxiliary electrode layer by vapor deposition.

[0091] k') The hole injection layer, hole transport layer, organic light-emitting layer, electron transport layer, electron injection layer, cathode layer, capping layer, auxiliary electrode layer, and third inorganic encapsulation layer of the R pixel area, G pixel area, and B pixel on the isolation pillar are removed by exposure, development, and etching to expose the isolation pillar.

[0092] It should be noted that in the display substrate prepared by the above steps a') to k'), the side of the isolation pillar away from the substrate is not covered by the light-emitting layer, cathode layer, capping layer, auxiliary electrode layer, or encapsulation layer of the R pixel (or G pixel, or B pixel). After step k'), the isolation pillar is exposed.

[0093] In some embodiments, when the encapsulation layer includes a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer, the first inorganic encapsulation layer can be formed by vapor deposition, the organic encapsulation layer can be formed on the first inorganic encapsulation layer by inkjet printing, and finally the second inorganic encapsulation layer can be formed on the organic encapsulation layer by vapor deposition.

[0094] This application also provides a display device, including the display substrate in any of the above possible embodiments.

[0095] The display device can be an OLED display or other display device, as well as any product or component with display function, such as a television, digital camera, mobile phone, or tablet computer that includes such display devices.

[0096] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A display substrate, characterized in that, include: Substrate (11); A pixel definition layer (12) and a plurality of light-emitting devices (13) are disposed on one side of the substrate (11). The pixel definition layer (12) includes a plurality of pixel openings. The plurality of light-emitting devices (13) correspond one-to-one with the plurality of pixel openings. At least a portion of the light-emitting device (13) is located within the pixel opening. The light-emitting device (13) includes an anode layer (131), a light-emitting layer (132), and a cathode layer (133) disposed sequentially along a first direction, where the first direction is the thickness direction of the display substrate. A plurality of isolation pillars (14) are disposed on the side of the pixel definition layer (12) away from the substrate (11). The isolation pillars (14) are disposed around the pixel opening to separate the light-emitting layers (132) of any two adjacent light-emitting devices (13). The isolation pillars (14) include a conductive structure (141) and an inorganic material layer (142) disposed sequentially along the first direction. An auxiliary electrode layer (15) is disposed on the side of the cathode layer (133) away from the substrate (11); The cathode layer (133) and the auxiliary electrode layer (15) are electrically connected to the conductive structure (141).

2. The display substrate according to claim 1, characterized in that, The inorganic material layer (142) extends beyond the conductive structure (141) at both ends in the second direction, which is perpendicular to the first direction.

3. The display substrate according to claim 2, characterized in that, The display substrate further includes a cover layer (16), which is disposed on the side of the cathode layer (133) away from the substrate (11), or the cover layer (16) is disposed on the side of the auxiliary electrode layer (15) away from the substrate (11).

4. The display substrate according to claim 3, characterized in that, The refractive index of the capping layer (16) is greater than that of the auxiliary electrode layer (15).

5. The display substrate according to claim 3 or 4, characterized in that, The orthographic projection of the cover layer (16) on the substrate (11) lies within the orthographic projection of the auxiliary electrode layer (15) on the substrate (11).

6. The display substrate according to any one of claims 2 to 5, characterized in that, The light-emitting device (13) further includes a first functional layer (134) and a second functional layer (135). The anode layer (131), the first functional layer (134), the light-emitting layer (132), the second functional layer (135) and the cathode layer (133) are arranged sequentially along the first direction. The cathode layer (133) covers the side of the second functional layer (135) away from the substrate (11) and the side edge of the second functional layer (135). The direction of the side edge of the second functional layer (135) intersects with the second direction.

7. The display substrate according to claim 6, characterized in that, The cathode layer (133) includes a first groove (1331), and the auxiliary electrode layer (15) includes a first portion (151) disposed on the side of the cathode layer (133) away from the substrate (11) and a second portion (152) located in the first groove (1331), wherein the first portion (151) and the second portion (152) are connected.

8. The display substrate according to claim 7, characterized in that, The display substrate further includes an encapsulation layer (17), which is disposed on the side of the auxiliary electrode layer (15) away from the substrate (11). The auxiliary electrode layer (15) includes a second groove (153), the orthographic projection of the second groove (153) on the substrate (11) being located within the orthographic projection of the first groove (1331) on the substrate (11), and a portion of the encapsulation layer (17) filling the second groove (153).

9. The display substrate according to any one of claims 1 to 8, characterized in that, The auxiliary electrode layer (15) is made of at least one of Yb, Bi, Co, Mo, Ti, Zr, Al, Cr, Nb, Pt, W, In, Sn, Fe, Ni, Ta, Mn, Zn, and Ge.

10. The display substrate according to any one of claims 3 to 5, characterized in that, The material of the capping layer (16) includes at least one of carbocyclic compounds, heterocyclic compounds, amino compounds, porphyrin derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalene phthalocyanine derivatives, alkali metal complexes, and alkaline earth metal complexes.

11. A display device, characterized in that, Includes the display substrate as described in any one of claims 1 to 10.

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