Display panel and its manufacturing method

Abstract

This application provides a display panel and its fabrication method. The display panel includes: a substrate; a first electrode layer disposed on one side of the substrate; and a light-emitting device layer disposed on the side of the first electrode layer away from the substrate. The first electrode layer has a plurality of slots corresponding to the positions of the light-emitting device layer, and quantum dot material is disposed within the slots. Light emitted downwards from the light-emitting device layer towards the first electrode layer can be absorbed by the quantum dot material, converting electroluminescence into photoluminescence, effectively reducing light energy loss caused by light coupling at the interface between the first electrode layer and the light-emitting device layer into a surface plasmonic film.

Description

Technical Field

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

[0002] With the development of display technology, organic light-emitting diode (OLED) flat panel display devices have become the mainstream in various consumer electronics products such as mobile phones, televisions, personal digital assistants, digital cameras, laptops, and desktop computers due to their advantages such as being all-solid-state, ultra-thin, having no viewing angle limitations, fast response, operating at room temperature, and being easy to realize flexible and 3D displays.

[0003] For top-emitting devices, the overall external quantum efficiency is typically only around 20%. Due to the influence of metal electrodes, about 40% of the light is coupled into surface plasmon modes, which are then converted into heat, causing energy loss and increasing the internal temperature of the device, thus affecting luminous efficiency. To achieve higher brightness, two approaches are being developed: firstly, higher-performance OLED materials are being developed to improve luminous efficiency; secondly, multi-unit stacked structures are being used to enhance both luminous efficiency and brightness. Both of these methods have limitations: OLED material development has a long cycle, performance improvements face certain bottlenecks, and stacked devices operate at high voltages and consume high power.

[0004] Therefore, improvements are urgently needed to address the shortcomings of existing technologies. Summary of the Invention

[0005] This application provides a display panel and its manufacturing method to improve the problem of light energy loss caused by light coupling to a surface plasmonic film state at the interface between the light-emitting layer and the electrode in current display panels.

[0006] This application provides a display panel, including: a substrate; a first electrode layer disposed on one side of the substrate; and a light-emitting device layer disposed on the side of the first electrode layer away from the substrate; wherein the first electrode layer has a plurality of holes corresponding to the positions of the light-emitting device layer, and quantum dot material is disposed in the holes.

[0007] Optionally, in one embodiment of this application, the first electrode layer includes: a reflective layer disposed on a side close to the substrate; and a first electrode disposed on a side of the reflective layer away from the substrate; the slot is disposed within the reflective layer and / or the first electrode.

[0008] Optionally, in one embodiment of this application, the material of the reflective layer includes metal; the material of the first electrode includes transparent oxide.

[0009] Optionally, in one embodiment of this application, the wavelength range of light absorbed by the quantum dot material at least partially overlaps with the wavelength range of light emitted by the light-emitting device layer.

[0010] Optionally, in one embodiment of this application, the quantum dot material includes a self-water and oxygen barrier material.

[0011] Optionally, in one embodiment of this application, the slots are uniformly disposed within the first electrode layer, and the minimum distance between two adjacent slots is greater than the shortest distance between the quantum dot materials where self-quenching occurs.

[0012] Optionally, in one embodiment of this application, the display panel further includes: a pixel definition layer disposed on the side of the first electrode layer away from the substrate, including at least one pixel opening, the pixel opening exposing a portion of the first electrode layer, and the light-emitting device layer correspondingly disposed within the pixel opening; a second electrode layer disposed on the side of the light-emitting device layer away from the first electrode layer, and at least covering the light-emitting device layer; and an encapsulation layer disposed on the substrate, and at least covering the second electrode layer.

[0013] Optionally, in one embodiment of this application, the density of the holes in the first electrode layer corresponding to different light-emitting device layers is different.

[0014] Accordingly, this application also provides a method for fabricating a display panel as described in any of the above embodiments, comprising the following steps: providing a substrate; depositing an electrode material on one side of the substrate and patterning it to form a first electrode layer; performing photolithography on the first electrode layer to form a plurality of holes and filling the holes with quantum dot material; printing a light-emitting material at the corresponding positions of the first electrode layer filled with the quantum dot material to form a light-emitting device layer.

[0015] Optionally, in one embodiment of this application, the method for fabricating the display panel further includes the following steps: depositing an organic material on the side of the first electrode layer away from the substrate and patterning it to form a pixel definition layer, wherein the pixel definition layer exposes the area of ​​the first electrode layer in which the hole is formed, so as to form a pixel opening; depositing an electrode material on the side of the light-emitting device layer away from the first electrode layer and patterning it to form a second electrode layer.

[0016] This application provides a display panel and its fabrication method. The display panel includes: a substrate; a first electrode layer disposed on one side of the substrate; and a light-emitting device layer disposed on the side of the first electrode layer away from the substrate. The first electrode layer has multiple slots corresponding to the positions of the light-emitting device layer, and quantum dot material is disposed within these slots. The wavelength range of light emitted by the quantum dot material at least partially overlaps with the wavelength range of light emitted by the light-emitting device layer. Light emitted downwards from the light-emitting device layer towards the first electrode layer can be absorbed by the quantum dot material. This allows the utilization of light energy lost at the interface between the first electrode layer and the light-emitting device layer due to photocoupling to a plasma mode. Furthermore, the high quantum efficiency of the quantum dot material converts electroluminescence into photoluminescence, effectively reducing light energy loss at the interface between the first electrode layer and the light-emitting device layer caused by photocoupling to a surface plasma film, as well as the internal heating problem caused by photocoupling losses in the display panel. Moreover, without affecting the overall thickness of the display panel, the quantum dot material and the top-layer light-emitting device layer can emit light simultaneously, significantly improving the luminous efficiency and brightness of the display panel. Attached Figure Description

[0017] 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.

[0018] Figure 1 A schematic diagram of the three-dimensional cross-sectional structure of the display panel provided in the embodiments of this application. Figure 1 ;

[0019] Figure 2 A schematic diagram of the three-dimensional cross-sectional structure of the display panel provided in the embodiments of this application. Figure 2 ;

[0020] Figure 3 A schematic diagram of the three-dimensional cross-sectional structure of the display panel provided in the embodiments of this application. Figure 3 ;

[0021] Figure 4 This is a schematic flowchart of the method for manufacturing the display panel provided in an embodiment of this application;

[0022] Figures 5 to 9 This is a schematic diagram of each step in the manufacturing method of the display panel provided in the embodiments of this application.

[0023] Explanation of key figure labels:

[0024]

[0025] Detailed Implementation

[0026] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "upper," "lower," "left," and "right" can refer to the actual direction of the device in use or operation, the direction of the drawing in the accompanying drawings, or two opposite directions; while "inner" and "outer" refer to the outline of the device.

[0027] Please see Figures 1 to 3This application provides a display panel 10, including a substrate 100, a first electrode layer 200, a pixel definition layer 300, a light-emitting device layer 400, a second electrode layer 500, and an encapsulation layer 600 stacked in one layer. Specifically, the first electrode layer 200 is disposed on one side of the substrate 100; the pixel definition layer 300 is disposed on the side of the first electrode layer 200 away from the substrate 100, including at least one pixel opening 310, the pixel opening 310 exposing a portion of the first electrode layer 200; the light-emitting device layer 400 is disposed on the side of the first electrode layer 200 away from the substrate 100, and is correspondingly disposed within the pixel opening 310; the second electrode layer 500 is disposed on the side of the light-emitting device layer 400 away from the first electrode layer 200, and at least covers the light-emitting device layer 400; and the encapsulation layer 600 is disposed on the substrate 100, and at least covers the second electrode layer 500. The first electrode layer 200 has multiple slots 201 corresponding to the positions of the light-emitting device layer 400, and quantum dot material is disposed within the slots 201. Light emitted downwards from the light-emitting device layer 400 towards the first electrode layer 200 can be absorbed by the quantum dot material. This allows the utilization of light energy lost at the interface between the first electrode layer 200 and the light-emitting device layer 400 due to photocoupling into a plasma mode. Furthermore, leveraging the high quantum efficiency of the quantum dot material, it converts electroluminescence into photoluminescence, effectively reducing light energy loss at the interface between the first electrode layer 200 and the light-emitting device layer 400 caused by photocoupling into a surface plasma film state, as well as the internal heating problem of the display panel 10 caused by photocoupling losses. Moreover, without affecting the overall thickness of the display panel, the quantum dot material and the top light-emitting device layer 400 can emit light simultaneously, significantly improving the luminous efficiency and brightness of the display panel 10.

[0028] In one embodiment of this application, the first electrode layer 200 includes a reflective layer 210 and a first electrode 220 stacked together. The reflective layer 210 is disposed on the side close to the substrate 100, and the first electrode 220 is disposed on the side of the reflective layer 210 away from the substrate 100; wherein a slot 201 is disposed within the reflective layer 210 and / or the first electrode 220. When the slot 201 is disposed on the reflective layer 210, the first electrode 220 covers the slot 201; when the slot 201 is disposed on the first electrode 220, the light-emitting device layer 400 covers the slot 201. Preferably, when the slot 201 is disposed on both the reflective layer 210 and the first electrode 220, the slots 201 located on the reflective layer 210 and the slots 201 located on the first electrode 220 are staggered, which can increase the density of the quantum dot materials while preventing self-quenching between adjacent quantum dot materials, thereby improving the light extraction efficiency of the display panel. In this embodiment, the material of the reflective layer 210 includes metals, such as silver, aluminum, and magnesium. The material of the first electrode 220 includes a transparent oxide, such as indium tin oxide. The first electrode 220 is an anode, meaning that the display panel 10 is a top-emitting display panel. Due to the presence of the reflective layer 210, the first electrode layer 200 can reflect the light emitted by the light-emitting device layer 400 to the light-emitting side of the display panel 10. The quantum dot material can reabsorb the light emitted by the light-emitting device layer 400 to achieve self-luminescence, thereby improving the luminous efficiency of the light-emitting device layer 400.

[0029] The wavelength range of light absorbed by the quantum dot material at least partially overlaps with the wavelength range of light emitted by the light-emitting device layer 400. Preferably, the wavelength range of light absorbed by the quantum dot material is greater than the wavelength range of light emitted by the light-emitting device layer 400; that is, the wavelength range of light emitted by the light-emitting device layer 400 is within the wavelength range of light absorbed by the quantum dot material. The quantum dot material includes a self-water and oxygen barrier material, which can reduce its influence during the preparation of subsequent film layers.

[0030] It is understandable that when quantum dot materials are too close together or concentrated in large quantities, self-quenching can easily occur, thus affecting the absorption of light by the quantum dot materials. In an embodiment, preferably, the slots 201 are uniformly disposed within the first electrode layer 200, and the minimum distance between two adjacent slots 201 is greater than the shortest distance between the quantum dot materials where self-quenching occurs. Since the light-emitting device layer 400 can emit three different colors of light, meaning that the light emitted by different colors of the light-emitting device layer 400 has different efficiencies, preferably, the density of slots 201 corresponding to the light-emitting device layer 400 with lower luminous efficiency is greater. Therefore, the density of quantum dot materials corresponding to the light-emitting device layer 400 with lower luminous efficiency is greater, thus improving the color uniformity of the display panel 10 and thereby enhancing the display effect. For example, the display panel 10 can emit red light, green light, and blue light. Since the blue material that emits blue light has not yet broken away from fluorescent materials that only use singlet excitons, its luminous efficiency is lower than that of red light or green light. This application can increase the density of the corresponding quantum dot material by increasing the number of the holes 201 corresponding to the light-emitting device layer 400 that emits blue light, thereby improving the light efficiency at the light-emitting device layer 400 that emits blue light through the self-luminescence of the quantum dot material, thereby achieving the effect of light emission balance.

[0031] In this application, the substrate 100 includes a substrate 110, a light-shielding metal layer 120, a buffer layer 130, an active layer 140, a gate insulating layer 150, a gate 160, an interlayer insulating layer 170, a source / drain electrode 180, and a planarization layer 190, which are stacked sequentially. Specifically, the light-shielding metal layer 120 is disposed on one side of the substrate 110; the buffer layer 130 is disposed on the side of the light-shielding metal layer 120 away from the substrate 110, and exposes a portion of the light-shielding metal layer 120; the active layer 140 is disposed on the side of the buffer layer 130 away from the light-shielding metal layer 120, and is disposed corresponding to the light-shielding metal layer 120; the gate insulating layer 150 is disposed on the side of the active layer 140 away from the buffer layer 130, and exposes a portion of the active layer 140; the gate 160 is disposed on the side of the gate insulating layer 150 away from the active layer 140, and is disposed corresponding to the active layer 140; the interlayer insulating layer 170 is disposed on the side of the gate 160 away from the gate insulating layer 130. On one side of the 50, and covering the gate 160, a portion of the light-shielding metal layer 120 and a portion of the active layer 140 are exposed; the source / drain electrode 180 is disposed on the side of the interlayer insulating layer 170 away from the gate 160, and is connected to the light-shielding metal layer 120 through a via penetrating the interlayer insulating layer 170 and the buffer layer 130, and is connected to the active layer 140 through a via penetrating the interlayer insulating layer 170; and the planarization layer 190 is disposed on the side of the source / drain electrode 180 away from the interlayer insulating layer 170, and a portion of the source / drain electrode 180 is exposed; wherein, the first electrode layer 200 is connected to the source / drain electrode 180 through a via penetrating the planarization layer 190 and the interlayer insulating layer 170.

[0032] The substrate 110 described in this application can be a flexible substrate, a glass substrate, or a flexible substrate. The materials used to fabricate the flexible substrate include, but are not limited to, polyimide and polyethylene terephthalate. The light-shielding metal layer 120 increases the stability of the devices within the substrate 100 under illumination. The buffer layer 130 is used for heat preservation and is any one of a silicon nitride layer, a silicon oxide layer, or an overlapping layer of silicon nitride and silicon oxide. The gate insulating layer 150 is any one of a silicon nitride layer, a silicon oxide layer, or an overlapping layer of silicon nitride and silicon oxide. The material of the gate 160 includes at least one of molybdenum, aluminum, titanium, chromium, and copper. The planarization layer 190 serves to planarize the devices within the substrate 100, facilitating the fabrication of other films in subsequent processes.

[0033] Please refer to the following: Figure 1 , Figures 4 to 9 Accordingly, embodiments of this application also provide a method for manufacturing the display panel described in any of the above embodiments, comprising the following steps:

[0034] like Figure 4 and Figure 5 As shown, step S1: Provide a substrate 100; the substrate 100 includes a substrate 110, a light-shielding metal layer 120, a buffer layer 130, an active layer 140, a gate insulating layer 150, a gate 160, an interlayer insulating layer 170, a source / drain electrode 180, and a planarization layer 190 stacked sequentially; the specific preparation method is not described in this application, and conventional methods can be used.

[0035] like Figure 4 and Figure 6 As shown, step S2: deposit electrode material on one side of the substrate and pattern it to form a first electrode layer 200, perform photolithography on the first electrode layer 200 to form a plurality of holes 201, and fill the holes 201 with quantum dot material.

[0036] like Figure 4 and Figure 7 As shown, in step S3: an organic material is deposited on the side of the first electrode layer 200 away from the substrate 100, and a pixel definition layer 300 is patterned to form the pixel definition layer 300, which exposes the area of ​​the first electrode layer 200 where the hole 201 is formed, thus forming a pixel opening 310.

[0037] like Figure 4 and Figure 8 As shown, step S4: A light-emitting material is printed at the corresponding positions where the quantum dot material is filled in the first electrode layer 200 to form a light-emitting device layer 400. The light-emitting device layer 400 is correspondingly disposed within the pixel opening 310.

[0038] like Figure 4 and Figure 9 As shown, step S5: deposit electrode material on the side of the light-emitting device layer 400 away from the first electrode layer 200, and pattern the second electrode layer 500.

[0039] like Figure 4 and Figure 1 As shown, step S6: deposit encapsulation material on the side of the second electrode layer 500 away from the light-emitting device layer 400 to form an encapsulation layer 600.

[0040] In one embodiment, taking the aperture 201 disposed on the reflective layer 210 as an example, step S2 further includes: step S21: depositing a metal material and patterning to form the reflective layer 210, performing photolithography on the reflective layer 210 to form a plurality of apertures 201, and filling the apertures 201 with quantum dot material; step S22: depositing a transparent oxide material and patterning to form a first electrode 220 on the side of the reflective layer 210 away from the substrate 100. It is understood that when the aperture 201 is disposed on the first electrode 220, the first electrode 220 needs to be photolithographically formed to form a plurality of apertures 201, and the apertures 201 need to be filled with quantum dot material.

[0041] The display panel 10 described in this application can be applied to any product or component with display function, such as mobile phones, tablets, televisions, monitors, laptops, digital photo frames, and navigators. Other essential components of the display panel 10 are understood by those skilled in the art and will not be described in detail here, nor should they be construed as limiting this application.

[0042] In summary, this application provides a display panel 10 and a method for fabricating the same. The display panel 10 includes: a substrate 100; a first electrode layer 200 disposed on one side of the substrate 100; and a light-emitting device layer 400 disposed on the side of the first electrode layer 200 away from the substrate 100. The first electrode layer 200 has a plurality of slots 201 at positions corresponding to the light-emitting device layer 400, and quantum dot material is disposed in the slots 201. The wavelength range of light emitted by the quantum dot material at least partially overlaps with the wavelength range of light emitted by the light-emitting device layer 400. Light emitted downwards from the light-emitting device layer 400 towards the first electrode layer 200 can be absorbed by the quantum dot material. This allows for the utilization of light energy lost at the interface between the first electrode layer 200 and the light-emitting device layer 400 due to photocoupling into a plasma mode. Furthermore, leveraging the high quantum efficiency of the quantum dot material, it converts electroluminescence into photoluminescence, effectively reducing light energy loss at the interface between the first electrode layer 200 and the light-emitting device layer 400 caused by photocoupling into a surface plasma film state, as well as reducing internal heat generation in the display panel 10 due to photocoupling losses. Moreover, without affecting the overall thickness of the display panel 10, the quantum dot material and the top-layer light-emitting device layer 400 can emit light simultaneously, significantly improving the luminous efficiency and brightness of the display panel 10.

[0043] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0044] The above provides a detailed description of a display panel 10 and its preparation method provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A display panel, characterized by, The display panel comprises: a substrate; a first electrode layer disposed on one side of the substrate; a light-emitting device layer disposed on the side of the first electrode layer away from the substrate; wherein the first electrode layer is provided with a plurality of holes corresponding to the positions of the light-emitting device layer, and quantum dot material is disposed in the holes, the wavelength range of light absorbed by the quantum dot material at least partially overlaps with the wavelength range of light emitted by the light-emitting device layer; wherein the light-emitting device layer covers the holes, and the minimum distance between adjacent two holes is greater than the shortest distance at which self-quenching occurs between the quantum dot materials. The first electrode layer comprises:

2. The display panel of claim 1, wherein, a reflective layer disposed on the side close to the substrate; and a first electrode disposed on the side of the reflective layer away from the substrate; wherein the holes are disposed in the reflective layer and / or the first electrode. The material of the reflective layer comprises metal; and the material of the first electrode comprises transparent oxide.

3. The display panel of claim 2, wherein, The quantum dot material comprises a water-oxygen barrier material.

4. The display panel of claim 1, wherein, The holes are uniformly disposed in the first electrode layer.

5. The display panel of claim 1, wherein, The display panel further comprises:

6. The display panel of claim 1, wherein, a pixel definition layer disposed on the side of the first electrode layer away from the substrate, comprising at least one pixel opening, the pixel opening exposes part of the first electrode layer, and the light-emitting device layer is correspondingly disposed in the pixel opening; a second electrode layer disposed on the side of the light-emitting device layer away from the first electrode layer, covering at least the light-emitting device layer, and an encapsulation layer disposed on the substrate and covering at least the second electrode layer. The density of the holes in the first electrode layer corresponding to different light-emitting device layers is different.

7. The display panel of claim 1, wherein, The method comprises the following steps:

8. A method for manufacturing a display panel, characterized by, providing a substrate; depositing electrode material on one side of the substrate and patterning to form a first electrode layer, performing photolithography on the first electrode layer to form a plurality of holes, and filling quantum dot material in the holes; printing light-emitting material on the corresponding positions of the first electrode layer filled with the quantum dot material to form a light-emitting device layer, wherein the wavelength range of light absorbed by the quantum dot material at least partially overlaps with the wavelength range of light emitted by the light-emitting device layer; the light-emitting device layer covers the holes, and the minimum distance between adjacent two holes is greater than the shortest distance at which self-quenching occurs between the quantum dot materials. The method further comprises the following steps:

9. The method of producing a display panel according to claim 8, wherein depositing organic material on the side of the first electrode layer away from the substrate and patterning to form a pixel definition layer, the pixel definition layer exposes the area of the first electrode layer where the holes are formed to form a pixel opening; depositing electrode material on the side of the light-emitting device layer away from the first electrode layer and patterning to form a second electrode layer. ​

Images