Display panel and preparation method thereof

Abstract

The application provides a display panel and a preparation method thereof. The display panel comprises a substrate, a plurality of light emitting devices, a first electrode and a pixel definition layer. The plurality of light emitting devices are located on the substrate. The first electrode is located above the substrate and is provided with a plurality of first openings. The pixel definition layer is located on the first electrode and is provided with a plurality of second openings. The plurality of second openings are located on the plurality of first openings and expose the plurality of light emitting devices. In the embodiment of the application, the first electrode is used to form an electric field to control the formation of the pixel definition layer structure, and the preparation method is simple and convenient.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a display panel and its manufacturing method. Background Technology

[0002] Organic light-emitting diodes (OLEDs) and quantum dot light-emitting diodes (QLEDs) have attracted widespread attention due to their advantages such as self-illumination, rich colors, fast response speed, wide viewing angle, light weight, and the ability to be made into flexible displays. In both OLED and QLED processes, the pixel confinement layer structure (bank) is indispensable as it effectively prevents the leakage of quantum dots or light-emitting material droplets during printing. Simultaneously, in display structures such as micro-LEDs, mini-LEDs, and QD color conversion layers, the bank structure can block light leakage from the light-emitting device at oblique viewing angles, thereby reducing color crosstalk between light-emitting pixels. Therefore, obtaining bank structures with specific functions is crucial.

[0003] Currently, bank structures are mainly fabricated using photolithography, and the bank is primarily composed of photoresist and black or white particles. During photolithography, to obtain a high-thickness bank structure, the absorption of light by the black material or the reflection of light by the white material makes it difficult for the light beam to penetrate the bank film. Consequently, the interior of the high-thickness bank cannot be removed by the developing solution, resulting in low resolution during photolithography fabrication and limiting its application in high-resolution displays.

[0004] Therefore, the existing display panel manufacturing process, which involves photolithography to create a pixel bank, limits its application in high-resolution displays and needs to be improved. Summary of the Invention

[0005] This invention provides a display panel and its manufacturing method to solve the technical problem that the existing photolithography process for pixel-delimiting layers (banks) limits its application in high-resolution displays.

[0006] To solve the above problems, the technical solution provided by the present invention is as follows:

[0007] This invention provides a display panel, comprising:

[0008] Substrate;

[0009] Multiple light-emitting devices are located on the substrate;

[0010] A first electrode is located above the substrate, and the first electrode has a plurality of first openings;

[0011] A pixel defining layer is located on the first electrode. The pixel defining layer has a plurality of second openings located on a plurality of first openings and exposing a plurality of light-emitting devices.

[0012] In the display panel provided in the embodiments of the present invention, the material of the pixel defining layer includes nanoparticles, and the surface of the nanoparticles has ligands.

[0013] In the display panel provided in the embodiments of the present invention, the ligand includes at least one of the following: ligands with amine, carboxyl, or thiol groups, n-octylthiol, trioctylphosphine, PEG-COOH, and ligands with long-chain polymers.

[0014] In the display panel provided in the embodiments of the present invention, the nanoparticles include black nanoparticles, which include at least one of carbon black, copper chromium black, carbonized titanium dioxide, or carbonized silicon dioxide; and / or, the nanoparticles include white nanoparticles, which include at least one of polymer nanospheres, titanium dioxide nanoparticles, polymers coated with titanium dioxide nanoparticles, calcium carbonate nanoparticles, or barium carbonate nanoparticles.

[0015] In the display panel provided in the embodiments of the present invention, the thickness of the pixel limiting layer is less than 1 micrometer, and the size range of the nanoparticles is 10 to 50 nanometers; or, the thickness of the pixel limiting layer is 1 to 5 micrometers, and the size range of the nanoparticles is 10 to 200 nanometers; or, the thickness of the pixel limiting layer is greater than 5 micrometers, and the size range of the nanoparticles is 50 to 500 nanometers.

[0016] In the display panel provided in the embodiments of the present invention, the pixel defining layer has the same shape as the first electrode, and at least a portion of the edge of the pixel defining layer extends beyond the edge of the first electrode.

[0017] In the display panel provided in the embodiments of the present invention, the display panel further includes a plurality of pixel electrodes, the plurality of pixel electrodes being located within a plurality of first openings, and the first electrodes and the plurality of pixel electrodes being disposed in the same layer and made of the same material.

[0018] Furthermore, embodiments of the present invention also provide a method for manufacturing a display panel, comprising:

[0019] Provide substrate;

[0020] A first electrode is fabricated on the substrate, and the first electrode has a plurality of first openings;

[0021] A pixel defining layer is fabricated on the first electrode, the pixel defining layer having a plurality of second openings, the plurality of second openings being located on a plurality of first openings; and

[0022] A plurality of light-emitting devices are fabricated on the substrate, and the plurality of light-emitting devices are exposed to a plurality of the second openings.

[0023] In the method for fabricating a display panel provided in this embodiment of the invention, the step of fabricating a pixel-defining layer on the first electrode includes:

[0024] A nanoparticle solution is coated on the first electrode, wherein the nanoparticles in the nanoparticle solution are in a charged state.

[0025] An electrode plate is placed above the nanoparticle solution, away from it.

[0026] A current is applied to the first electrode and the surface electrode plate to form the pixel-defining layer on the first electrode by means of the nanoparticle solution, wherein the voltage polarity of the first electrode is different from that of the nanoparticles, and the voltage polarity of the surface electrode plate is the same as that of the nanoparticles.

[0027] In the method for fabricating a display panel provided in this embodiment of the invention, the display panel further includes a plurality of pixel electrodes, the plurality of pixel electrodes being disposed at positions corresponding to the first opening; the step of fabricating a pixel defining layer on the first electrode includes:

[0028] A nanoparticle solution is coated on top of the first electrode and the plurality of pixel electrodes, wherein the nanoparticles in the nanoparticle solution are in a charged state.

[0029] A voltage is applied to the first electrode and the plurality of pixel electrodes to form the pixel defining layer on the first electrode, wherein the voltage polarity of the first electrode is different from that of the nanoparticles, and the voltage polarity of the plurality of pixel electrodes is the same as that of the nanoparticles.

[0030] The beneficial effects of this invention are as follows: This invention provides a display panel and its fabrication method; the display panel includes a substrate, a plurality of light-emitting devices, a first electrode, and a pixel defining layer. The plurality of light-emitting devices are located on the substrate, the first electrode is located above the substrate and has a plurality of first openings, and the pixel defining layer is located on the first electrode and has a plurality of second openings. The plurality of second openings are located on the plurality of first openings and expose the plurality of light-emitting devices. In this embodiment of the invention, the pixel defining layer structure is controlled by using an electric field generated by the first electrode, and the fabrication method is simple and convenient. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic cross-sectional view of the first type of display panel provided in an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of the cross-sectional structure of nanoparticles overflowing to the outside of the first electrode provided in an embodiment of the present invention;

[0034] Figure 3 This is a schematic cross-sectional view of a second type of display panel provided in an embodiment of the present invention;

[0035] Figures 4a to 4e A schematic diagram illustrating the manufacturing process of the first type of display panel provided in an embodiment of the present invention;

[0036] Figures 4f to 4h This is a schematic diagram illustrating the manufacturing process of the second type of display panel provided in an embodiment of the present invention. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0038] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, 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. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0039] In this application, the term "exemplary" is used to mean "serving as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0040] The present invention addresses the technical problem that the photolithography process for the pixel bank in existing display panels limits their application in high-resolution displays.

[0041] To address the aforementioned issues, this application provides a display panel. Specifically, the display panel provided in this application includes a substrate, a plurality of light-emitting devices, a first electrode, and a pixel defining layer. The plurality of light-emitting devices are located on the substrate, the first electrode is located above the substrate and has a plurality of first openings, and the pixel defining layer is located on the first electrode and has a plurality of second openings. The plurality of second openings are located on the plurality of first openings and expose the plurality of light-emitting devices.

[0042] The display panel provided in this application will be described in detail below through specific embodiments.

[0043] In one embodiment, please refer to Figure 1 , Figure 2 and Figure 3 .like Figure 1 As shown, the display panel provided in this embodiment of the invention includes:

[0044] Substrate 11;

[0045] Multiple light-emitting devices (not shown in the figure) are located on the substrate;

[0046] The first electrode 12 is located above the substrate 11, and the first electrode 12 is provided with a plurality of first openings 14;

[0047] A pixel defining layer 13 is located on the first electrode 12. The pixel defining layer 13 has a plurality of second openings 15, which are located on a plurality of first openings 14 and expose a plurality of light-emitting devices.

[0048] It should be noted that in this embodiment, the first electrode 12 is also called a bank electrode (pixel-defining layer electrode). In this embodiment of the invention, the first electrode is used to form an electric field to control the formation of a pixel-defining layer structure. By patterning the first electrode, the patterning of the pixel-defining layer structure can be achieved. This method uses photolithography to prepare a high-precision first electrode to achieve a high-precision pixel-defining layer structure. The shape of the pixel-defining layer is the same as the shape of the first electrode. The thickness of the pixel-defining layer can be precisely adjusted in the range of tens of nanometers to tens of micrometers. The method is simple and convenient, suitable for various types of pixel-defining layer materials, and suitable for large-scale commercial production.

[0049] This invention provides a display panel and its fabrication method. The display panel includes a substrate, a plurality of light-emitting devices, a first electrode, and a pixel defining layer. The plurality of light-emitting devices are located on the substrate, the first electrode is located above the substrate and has a plurality of first openings, and the pixel defining layer is located on the first electrode and has a plurality of second openings. The plurality of second openings are located on the plurality of first openings and expose the plurality of light-emitting devices. This invention utilizes an electric field generated by the first electrode to control the formation of the pixel defining layer structure, and the fabrication method is simple and convenient.

[0050] In one embodiment, the pixel defining layer 13 is made of nanoparticles, the surface of which has ligands; specifically, in this embodiment of the invention, an electric field is used to drive charged nanoparticles to move and aggregate onto the first electrode 12, thereby forming a tightly packed nanoparticle film, the nanoparticle film forming the pixel defining layer 13 on the first electrode 12.

[0051] Furthermore, in order to achieve charging of nanoparticles, it is necessary to modify the surface of the nanoparticles, such as by using ligands to modify the surface of the nanoparticles.

[0052] In one embodiment, the ligand includes at least one of the following: ligands with amino, carboxyl, or thiol groups; n-octylthiol; trioctylphosphine; PEG-COOH; and ligands with long-chain polymers. Furthermore, the choice of solvent mainly depends on the dispersibility of the nanoparticles and may include PGMEA, octane, n-hexane, DMF, DMSO, ethanol, etc.

[0053] Preferably, in order to improve the charge of nanoparticles, ligands that can ionize in a solvent can be selected, and the solvent can be a polar solvent such as ethanol, DMF, or PGMEA.

[0054] Preferably, in order to achieve stable deposition of nanoparticles on the first electrode without removal by subsequent processing, the surface of the nanoparticles needs to be specially designed. For example, the surface of the nanoparticles can be modified with ligands containing long-chain polymers such as PEG. Under the action of an electric field, the electric field force of this type of ligand overcomes the repulsive force between particles, causing them to approach each other. This type of long-chain ligand is adsorbed together by intermolecular forces, thus aggregating and precipitating out of the solution, no longer dissolving in the solution, and thus being stably deposited on the first electrode. A further design can be to add polymer monomers to the solution. These monomers can interact with the ligands and react with the ligands under light, thus polymerizing together to form a more stable pixel-defined layer structure.

[0055] In one embodiment, the nanoparticles include black nanoparticles, which include at least one of carbon black, copper chromium black, carbonized titanium dioxide, or carbonized silicon dioxide; and / or, the nanoparticles include white nanoparticles, which include at least one of polymer nanospheres, titanium dioxide nanoparticles, polymers coated with titanium dioxide or other nanoparticles, calcium carbonate nanoparticles, or barium carbonate nanoparticles. Specifically, the pixel-defining layer structure formed by the black nanoparticles can effectively block the oblique angle emission of pixel light, thereby reducing crosstalk between pixels of different colors; while the pixel-defining layer structure formed by the white nanoparticles can not only block crosstalk, but also reduce the absorption of light by the pixel-defining layer on the light-emitting pixels and reflect the light back, thereby allowing more light to be emitted from the positive viewing angle, thus effectively improving the light efficiency of display technologies such as micro-LED, mini-LED, and QD color conversion layer.

[0056] Furthermore, in another embodiment, the pixel defining layer is gray, which is achieved by depositing black nanoparticles and white nanoparticles mixed in a specific ratio.

[0057] In one embodiment, the thickness of the pixel-defining layer 13 is less than 1 micrometer, and the size of the nanoparticles ranges from 10 to 50 nanometers; or, the thickness of the pixel-defining layer 13 ranges from 1 to 5 micrometers, and the size of the nanoparticles ranges from 10 to 200 nanometers; or, the thickness of the pixel-defining layer 13 is greater than 5 micrometers, and the size of the nanoparticles ranges from 50 to 500 nanometers. It is understood that different sizes of nanoparticles can be selected for pixel-defining layer structures with different thickness requirements; when the pixel-defining layer structure is less than 1 micrometer, then... Nanoparticles of 10 to 50 nanometers can be selected. Based on the principle that the packing density of electrodeposited films increases with the increase of electric field strength, nanoparticles of this size can be used under a stronger electric field to obtain pixel-defining layer films with higher packing density, thereby improving the reflectivity (white pixel-defining layer) or absorptivity (black pixel-defining layer) of the pixel-defining layer structure. When the thickness of the pixel-defining layer is 1 to 5 micrometers, nanoparticles of 10 to 200 nanometers can be selected. When the thickness of the pixel-defining layer is greater than 5 micrometers, nanoparticles of 50 to 500 nanometers can be selected.

[0058] In one embodiment, the pixel defining layer 13 has the same shape as the first electrode 12, and at least a portion of the edge of the pixel defining layer 13 extends beyond the edge of the first electrode 12. Specifically, in this embodiment of the invention, charged nanoparticles are driven by an electric field to move onto the first electrode 12, which has an opposite charge to the charged nanoparticles, and are deposited and aggregated on the first electrode 12 to form the pixel defining layer 13. The formed pixel defining layer 13 has the same shape as the first electrode 12, and the size of the pixel defining layer 13 can be the same as the size of the first electrode 12 or slightly larger than the size of the first electrode 12, that is, at least a portion of the edge of the pixel defining layer 13 extends beyond the edge of the first electrode 12.

[0059] Specifically, when the nanoparticle size is large, the resulting pixel-defining layer 13 is larger than the size of the first electrode 12, such as... Figure 2 As shown, because the nanoparticles will slightly spill out of the first electrode 12, the smaller the size of the nanoparticles, the closer the size of the pixel defining layer 13 is to the size of the first electrode 12.

[0060] In one embodiment, such as Figure 3As shown, the display panel also includes a plurality of pixel electrodes 16, which are located within a plurality of first openings 14. The first electrode 12 and the plurality of pixel electrodes 16 are disposed in the same layer and are made of the same material. Specifically, for a display device using QD color conversion layer technology, if the QD pixel structure is processed by electrodeposition, pixel electrodes 16 need to be processed in the pixel area. The pixel electrodes 16 are located within the first openings 14. When the material of the first electrode 12 and the plurality of pixel electrodes 16 is indium tin oxide (ITO), the first electrode 12 and the plurality of pixel electrodes 16 can be fabricated using the same photolithography step, that is, the first electrode 12 and the plurality of pixel electrodes 16 are disposed in the same layer and are made of the same material.

[0061] It is understood that, in another embodiment, the material of the first electrode 12 includes metals such as silver or aluminum. In this case, the first electrode 12 can effectively reflect the blue backlight at the bottom, reduce the absorption of blue light by the pixel limiting layer 13, and thus improve the utilization efficiency of the blue backlight.

[0062] Furthermore, embodiments of this application also provide a method for manufacturing a display panel, the method comprising:

[0063] Provide substrate;

[0064] A first electrode is fabricated on the substrate, and the first electrode has a plurality of first openings;

[0065] A pixel defining layer is fabricated on the first electrode, the pixel defining layer having a plurality of second openings, the plurality of second openings being located on a plurality of first openings; and

[0066] A plurality of light-emitting devices are fabricated on the substrate, and the plurality of light-emitting devices are exposed to a plurality of the second openings.

[0067] Now combined Figure 3 , Figures 4a to 4h The method for manufacturing the display panel provided in the embodiments of this application will be described.

[0068] In one embodiment, OLED, QLED, and / or micro / mini-LED are used as examples to illustrate the fabrication method of the display panel. Figures 4a to 4e As shown, the method for manufacturing the display panel provided in this application includes the following steps:

[0069] Step 1: Provide a substrate.

[0070] Specifically, such as Figure 4a As shown, a substrate is provided as the substrate 11 of the display panel. The material of the substrate 11 includes glass, plexiglass, rigid insulating film, flexible insulating film, etc.

[0071] Step 2: Fabricate the first electrode on the substrate.

[0072] Specifically, such as Figure 4b As shown, a first electrode 12 is fabricated above the substrate 11, and the first electrode 12 has a plurality of first openings; the material of the first electrode 12 includes indium tin oxide (ITO), graphene, metals such as gold, silver, copper, and aluminum, and transition metal chalcogenides (MoS2, MoSe2, WS2, WSe2), etc.

[0073] Step 3: Prepare a pixel-defining layer on the first electrode.

[0074] Specifically, the pixel defining layer is located on the first electrode, and the pixel defining layer has a plurality of second openings, which are located on a plurality of first openings; the material of the pixel defining layer includes nanoparticles, and the shape of the pixel defining layer is the same as the shape of the first electrode.

[0075] Furthermore, the step of fabricating a pixel-defining layer on the first electrode includes:

[0076] Step 31: Coat the first electrode with a nanoparticle solution.

[0077] Specifically, such as Figure 4c As shown, a nanoparticle solution is scraped or dropped onto the first electrode 12 to form a uniform nanoparticle solution layer. The nanoparticles have ligands on their surface, and the nanoparticles in the nanoparticle solution are in a charged state. The nanoparticles are charged by modifying their surface with ligands. The nanoparticles include black nanoparticles and / or white nanoparticles. The black nanoparticles include at least one of carbon black, copper chromium black, carbonized titanium dioxide, or carbonized silicon dioxide. The white nanoparticles include at least one of polymer nanospheres, titanium dioxide nanoparticles, polymers coated with titanium dioxide and other nanoparticles, calcium carbonate nanoparticles, or barium carbonate nanoparticles.

[0078] Step 32: Place the surface electrode plate above the nanoparticle solution, away from it.

[0079] Specifically, such as Figure 4d As shown, a full-surface electrode plate 19 is placed above the nanoparticle solution away from it, so that it forms a cell structure with the substrate 11.

[0080] Step 33: Form a pixel-defining layer on the first electrode.

[0081] like Figure 4eAs shown, current is applied to the first electrode 12 (shielded by the pixel-defining layer 13 in the figure) and the surface electrode plate 19 to form the pixel-defining layer 13 on the first electrode 12 using the nanoparticle solution. The voltage characteristics of the first electrode 12 are different from those of the nanoparticles, while the voltage characteristics of the surface electrode plate 19 are the same as those of the nanoparticles. Specifically, after the surface electrode plate 19 and the substrate 11 form a cell structure, special voltages are applied to the upper surface electrode plate 19 and the first electrode 12 on the lower substrate 11, respectively. A fixed voltage (0V-1000V) is applied to create a vertical electric field. Under the influence of this electric field (electric field strength 0V / μm-20V / μm), charged particles move to the corresponding positions on the first electrode 12. If the nanoparticles are negatively charged, a positive charge is applied to the first electrode 12; if the nanoparticles are positively charged, a negative charge is applied to the first electrode 12. The shape of the first electrode 12 is the shape of the resulting pixel-defining layer 13. The thickness of the pixel-defining layer 13 can be increased by increasing the electric field strength or by increasing the concentration and content of the nanoparticles.

[0082] Step 4: Fabricate multiple light-emitting devices on the substrate.

[0083] Specifically, a plurality of light-emitting devices (not shown in the figure) are fabricated on the substrate, and the plurality of light-emitting devices are exposed through a plurality of the second openings; the light-emitting devices include OLED light-emitting devices or LED beads.

[0084] Finally, the surface electrode plate 19 is removed, thus completing the fabrication of the display panel.

[0085] As can be seen from the above description, the method for preparing the display panel provided in this application uses an electric field formed by the first electrode to control the formation of the pixel-defining layer structure. The preparation method is simple and convenient, suitable for various types of pixel-defining layer materials, and suitable for large-scale commercial production.

[0086] In another embodiment, a display device using QD color conversion layer technology is used as an example to illustrate the fabrication method of the display panel. Figure 3 , Figures 4f to 4h As shown, the display panel provided in this application further includes a plurality of pixel electrodes 16, which are disposed at positions corresponding to the first opening 14; the method for manufacturing the display panel includes the following steps:

[0087] Step 1: Provide a substrate.

[0088] Specifically, such as Figure 4a As shown, a substrate is provided as the substrate 11 of the display panel. The material of the substrate 11 includes glass, plexiglass, rigid insulating film, flexible insulating film, etc.

[0089] Step 2: Fabricate the first electrode and pixel electrode on the substrate.

[0090] Specifically, such as Figure 4f As shown, a first electrode 12 is fabricated above the substrate 11. The first electrode 12 has multiple first openings, and multiple pixel electrodes 16 are disposed corresponding to the positions of the first openings. The material of the first electrode 12 includes metals such as indium tin oxide (ITO), graphene, gold, silver, copper, and aluminum, as well as transition metal chalcogenides (MoS2, MoSe2, WS2, WSe2). The pixel electrodes 16 include transparent electrode materials such as indium tin oxide (ITO). When the materials of the first electrode 12 and the multiple pixel electrodes 16 are both indium tin oxide (ITO), the first electrode 12 and the multiple pixel electrodes 16 are fabricated using the same photolithography step. The pixel electrodes 16 can be powered by external circuits through bottom hole routing, or the first electrode 12 can be powered by external circuits by connecting wires through bottom hole routing.

[0091] Step 3: Prepare a pixel-defining layer on the first electrode.

[0092] Specifically, the pixel defining layer is located on the first electrode, and the pixel defining layer has a plurality of second openings, which are located on a plurality of first openings; the material of the pixel defining layer includes nanoparticles, and the shape of the pixel defining layer is the same as the shape of the first electrode.

[0093] Furthermore, the step of fabricating a pixel-defining layer on the first electrode includes:

[0094] Step 31: Coat the first electrode and multiple pixel electrodes with a nanoparticle solution.

[0095] Specifically, such as Figure 4g As shown, a nanoparticle solution is scraped or dropped onto the first electrode 12 and the plurality of pixel electrodes 16 to form a uniform nanoparticle solution layer. The nanoparticles have ligands on their surfaces, and the nanoparticles in the nanoparticle solution are in a charged state. The nanoparticles are charged by modifying their surfaces with ligands. The nanoparticles include black nanoparticles and / or white nanoparticles. The black nanoparticles include at least one of carbon black, copper chromium black, carbonized titanium dioxide, or carbonized silicon dioxide. The white nanoparticles include at least one of polymer nanospheres, titanium dioxide nanoparticles, polymers coated with titanium dioxide and other nanoparticles, calcium carbonate nanoparticles, or barium carbonate nanoparticles.

[0096] Step 32: Form a pixel-defining layer on the first electrode.

[0097] like Figure 4hAs shown, current is applied to the first electrode 12 (which is shielded by the pixel defining layer 13 in the figure) and the plurality of pixel electrodes 16 to form the pixel defining layer 13 on the first electrode 12. The voltage and electrical properties of the first electrode 12 are different from those of the nanoparticles, while the voltage and electrical properties of the plurality of pixel electrodes 16 are the same as those of the nanoparticles. Specifically, specific positive and negative electric fields are applied to the pixel electrodes 16 and the first electrode 12 respectively, thereby achieving the deposition and aggregation of nanoparticles on the first electrode, and thus forming the pixel defining layer 13 on the first electrode 12.

[0098] Step 4: Deposit QD on the pixel electrode.

[0099] Specifically, such as Figure 3 As shown, QD pixel structures are fabricated on the plurality of pixel electrodes 16 using an electrodeposition method, wherein the QDs are exposed through a plurality of second openings; wherein the QDs include red QD17 and green QD18; by designing the dimensions of the QD materials and nanoparticle materials, the dimensions of the deposited pixel-defining layer 13 and QDs are slightly larger than the dimensions of the first electrode 12 and the pixel electrode 16, thereby filling the gap between the first electrode 12 and the pixel electrode 16, thus preventing the leakage of blue backlight.

[0100] This completes the fabrication of the display panel.

[0101] As can be seen from the above description, the method for preparing the display panel provided in this application uses an electric field formed by the first electrode to control the formation of the pixel-defining layer structure. The preparation method is simple and convenient, suitable for various types of pixel-defining layer materials, and suitable for large-scale commercial production.

[0102] Accordingly, this application also provides a display panel fabrication apparatus, which uses the display panel fabrication method described in the above embodiments to fabricate the display panel.

[0103] As can be seen from the above embodiments:

[0104] This invention provides a display panel and its fabrication method. The display panel includes a substrate, a plurality of light-emitting devices, a first electrode, and a pixel-defining layer. The plurality of light-emitting devices are located on the substrate, the first electrode is located above the substrate and has a plurality of first openings, and the pixel-defining layer is located on the first electrode and has a plurality of second openings. The plurality of second openings are located on the plurality of first openings and expose the plurality of light-emitting devices. This invention utilizes an electric field generated by the first electrode to control the formation of the pixel-defining layer structure. The fabrication method is simple and convenient, suitable for various types of pixel-defining layer materials, and suitable for large-scale commercial production.

[0105] In summary, although the present invention has been disclosed above with reference to preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope defined in the claims.

Claims

1. A display panel, characterized in that, include: Substrate; Multiple light-emitting devices are located on the substrate; A first electrode is located above the substrate, and the first electrode has a plurality of first openings; A pixel defining layer is located on the first electrode, the pixel defining layer having a plurality of second openings, the plurality of second openings being located on the plurality of first openings and exposing a plurality of light-emitting devices; The pixel defining layer is made of nanoparticles, the surface of which has ligands, and the surface of which is modified by ligands to achieve charging.

2. The display panel according to claim 1, characterized in that, The ligands include at least one of the following: ligands with amine, carboxyl, or thiol groups; n-octylthiol; trioctylphosphine; PEG-COOH; and ligands with long-chain polymers.

3. The display panel according to claim 1, characterized in that, The nanoparticles include black nanoparticles, which include at least one of carbon black, copper chromium black, carbonized titanium dioxide, or carbonized silicon dioxide; and / or, the nanoparticles include white nanoparticles, which include at least one of polymer nanospheres, titanium dioxide nanoparticles, polymers coated with titanium dioxide nanoparticles, calcium carbonate nanoparticles, or barium carbonate nanoparticles.

4. The display panel according to claim 1, characterized in that, The thickness of the pixel-defining layer is less than 1 micrometer, and the size of the nanoparticles ranges from 10 to 50 nanometers; or, the thickness of the pixel-defining layer ranges from 1 to 5 micrometers, and the size of the nanoparticles ranges from 10 to 200 nanometers; or, the thickness of the pixel-defining layer is greater than 5 micrometers, and the size of the nanoparticles ranges from 50 to 500 nanometers.

5. The display panel according to claim 1, characterized in that, The pixel defining layer has the same shape as the first electrode, and at least a portion of the edge of the pixel defining layer extends beyond the edge of the first electrode.

6. The display panel according to any one of claims 1 to 5, characterized in that, The display panel also includes a plurality of pixel electrodes, which are located within a plurality of the first openings, and the first electrodes and the plurality of pixel electrodes are disposed in the same layer and are made of the same material.

7. A method for manufacturing a display panel, characterized in that, include: Provide substrate; A first electrode is fabricated on the substrate, and the first electrode has a plurality of first openings; A pixel defining layer is fabricated on the first electrode, the pixel defining layer having a plurality of second openings, the plurality of second openings being located on a plurality of first openings; as well as A plurality of light-emitting devices are fabricated on the substrate, and the plurality of light-emitting devices are exposed through a plurality of the second openings; The pixel defining layer is made of nanoparticles, the surface of which has ligands, and the surface of which is modified by ligands to achieve charging.

8. The method for manufacturing a display panel according to claim 7, characterized in that, The step of fabricating a pixel-defining layer on the first electrode includes: A nanoparticle solution is coated on the first electrode, wherein the nanoparticles in the nanoparticle solution are in a charged state. An electrode plate is placed above the nanoparticle solution, away from it. A current is applied to the first electrode and the surface electrode plate to form the pixel-defining layer on the first electrode by means of the nanoparticle solution, wherein the voltage polarity of the first electrode is different from that of the nanoparticles, and the voltage polarity of the surface electrode plate is the same as that of the nanoparticles.

9. The method for manufacturing a display panel according to claim 7, characterized in that, The display panel further includes a plurality of pixel electrodes, which are disposed corresponding to the positions of the first opening; the step of fabricating a pixel-defining layer on the first electrode includes: A nanoparticle solution is coated on top of the first electrode and the plurality of pixel electrodes, wherein the nanoparticles in the nanoparticle solution are in a charged state. A voltage is applied to the first electrode and the plurality of pixel electrodes to form the pixel defining layer on the first electrode, wherein the voltage polarity of the first electrode is different from that of the nanoparticles, and the voltage polarity of the plurality of pixel electrodes is the same as that of the nanoparticles.

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