Display panel, manufacturing method thereof and display device
By designing a multi-layered light-emitting structure and a composite anode layer, the efficiency and stability issues of OLED display panels have been resolved, improving luminous efficiency and lifespan, as well as enhancing color purity and brightness.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-27
- Publication Date
- 2026-03-10
AI Technical Summary
Existing OLED display panels face challenges in improving efficiency and stability in terms of high resolution, high color gamut, and long lifespan. In particular, the luminous efficiency of blue and green light devices is low, carrier injection and transport are unbalanced, and the microcavity effect is insufficient.
A multi-layer light-emitting structure is adopted, including N-type and P-type charge generation layers, an intermediate functional layer is introduced between the blue and green light-emitting layers, and a composite structure layer is used in the anode layer, containing metal and metal oxide materials. The hole layer and electron layer materials are optimized, and perovskite materials are used to improve the green and red light-emitting layers.
It improves luminous efficiency and lifespan, enhances the exciton recombination region, strengthens the microcavity effect, and improves display color purity and brightness.
Smart Images
Figure CN121646162A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of semiconductor, and particularly relates to a display panel and a manufacturing method thereof, and a display device. BACKGROUND
[0002] Organic light emitting diode (OLED) display technology, as a new generation of display technology, has been widely used in the consumer electronics field due to its self-luminous, wide viewing angle, high contrast, fast response speed and other advantages. With the development of display technology towards high resolution, high color gamut and long service life, the performance requirements of OLED display panels are increasingly improved.
[0003] The efficiency improvement and life improvement of the existing display panel are still the industry pain points and need to be solved urgently. SUMMARY
[0004] The present application aims to solve the problems in the prior art and proposes a display panel and a manufacturing method thereof, and a display device.
[0005] The present application first discloses a display panel, comprising: a substrate; an anode layer disposed on the substrate; a plurality of light emitting structure layers disposed on the anode layer, each of the light emitting structure layers comprising a blue light emitting layer, a green light emitting layer and a red light emitting layer; a charge generation layer disposed between two adjacent light emitting structure layers; a cathode layer disposed on the plurality of light emitting structure layers; the anode layer comprises a composite structure layer; wherein an intermediate functional layer is disposed between the blue light emitting layer and the green light emitting layer.
[0006] In the above display panel, the charge generation layer comprises an N-type charge generation layer and a P-type charge generation layer.
[0007] In the above display panel, the composite structure layer comprises a metal material and a metal oxide material.
[0008] In the above display panel, the composite structure layer further comprises at least one selected from a nanostructure layer, an insulating material layer and a conductive polymer layer.
[0009] In the above display panel, a hole layer is disposed between the anode layer and the light emitting structure layer, and the hole layer comprises a hole injection layer and a hole transport layer.
[0010] In the above display panel, an electron blocking layer is disposed between the hole transport layer and the blue light emitting layer.
[0011] In the display panel, an electron transport layer is arranged on the red light-emitting layer, the display panel further comprises a light extraction layer and an encapsulation layer arranged on the cathode layer, and the display panel further comprises a color filter layer arranged on the encapsulation layer.
[0012] In the display panel, at least one of the green light-emitting layer and the red light-emitting layer comprises a perovskite material.
[0013] In a second aspect, the present application provides a display device comprising the display panel.
[0014] In a third aspect, the present application provides a manufacturing method of a display panel, comprising: forming an anode layer on a substrate; forming a plurality of light-emitting structure layers on the anode layer, each of the light-emitting structure layers comprising a blue light-emitting layer, an intermediate functional layer, a green light-emitting layer and a red light-emitting layer formed in sequence; forming a charge generation layer between any two adjacent light-emitting structure layers; forming a cathode layer on the plurality of light-emitting structure layers.
[0015] The present application has the following advantages: 1. The present application provides a plurality of light-emitting structure layers, and the N-type charge generation layer and the P-type charge generation layer between any two light-emitting structure layers can effectively improve the light-emitting efficiency; meanwhile, the anode comprises a composite structure of metal and metal oxide, and can be further optimized by using nano-grating structure, composite coating and new conductive polymer materials, etc., which can effectively improve the interface effect of the anode and improve the reflectivity of the anode, enhance the microcavity effect, and improve the brightness and service life of the product.
[0016] 2. Compared with the traditional BGR device structure, the present application introduces the ITL layer as the intermediate functional layer between the blue light-emitting layer and the green light-emitting layer for transmission, which can effectively improve the distribution of exciton recombination region, improve the exciton recombination probability of the blue and green devices, improve the light-emitting efficiency of the blue light-emitting layer and the green light-emitting layer, effectively improve the display spectrum of the green light-emitting layer and the blue light-emitting layer, and improve the display color purity. BRIEF DESCRIPTION OF DRAWINGS
[0017] Fig. 1 FIG. 1 is a structural schematic diagram of the display panel disclosed by the present application.
[0018] Fig. 2 FIG. 2 is a structural schematic diagram of the comparative example provided by the present application.
[0019] Fig. 3 FIG. 3 is a data graph of anode reflectivity in different embodiments of the display panel disclosed by the present application.
[0020] 1 substrate, 2 anode layer, 3 light emitting structure layer, 31 blue light emitting layer, 32 green light emitting layer, 33 red light emitting layer, 34 intermediate functional layer, 35 electron blocking layer, 36 electron transport layer, 4 cathode layer, 5 light extraction layer, 6 encapsulation layer, 7 color filter layer, 8 hole layer, 81 hole injection layer, 82 hole transport layer, 9 charge generation layer, 91 N-type charge generation layer, 92 P-type charge generation layer. DETAILED DESCRIPTION
[0021] In order to facilitate the understanding of the present application, in order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below. In the following description, a lot of specific details are set forth in order to give a full understanding of the present application, and the preferred embodiments of the present application are given in the accompanying drawings. However, the present application can be implemented in many different forms, and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. The present application can be implemented in many different ways from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, therefore the present application is not limited to the specific embodiments disclosed below. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly and specifically limited. In the description of the present application, the meaning of "several" is at least one, such as one, two, etc., unless otherwise explicitly and specifically limited. It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be a middle element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not the only embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by those skilled in the art to which the present application belongs. The terms used herein are only for the description of specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more related listed items.
[0022] In a conventional OLED device structure, a single light-emitting layer structure is usually adopted to realize color display. However, this structure has obvious limitations: first, the distribution of exciton recombination regions between different color light-emitting layers in the single light-emitting layer structure is uneven, resulting in low light-emitting efficiency of blue and green devices, and the stability problem of blue light materials has always been a technical difficulty; second, the balance of carrier injection and transport in the single layer structure is difficult to optimize, affecting the overall efficiency and service life of the device; in addition, the conventional structure has deficiencies in the use of microcavity effect, limiting the further improvement of color purity and light-emitting efficiency.
[0023] In order to improve the performance of the device, various improvement schemes have been tried in the industry. For example, by introducing a multi-layer structure in the light-emitting layer to improve the carrier balance, or by optimizing the electrode structure to enhance the light extraction efficiency. However, these schemes often cannot solve the problems of efficiency improvement and stability improvement at the same time. In particular, in high-resolution micro-display applications, the conventional structure faces greater challenges in current density distribution, thermal management, etc. Based on the above reasons, the present application designs a display panel and a manufacturing method thereof, and a display device.
[0024] Reference Figs. 1-3 The present application provides a display panel, which is provided with a substrate 1 in the vertically upward direction, the substrate 1 is made of Si or TFT material, or other materials that can be used for OLED, and a driving circuit is made on the substrate, wherein the driving circuit can be selected from CMOS or TFT structure. Above the substrate 1 is an anode layer 2, which in the present scheme adopts a composite structure and includes at least metal and metal oxide, the manufacturing materials of the anode layer 2 include but are not limited to one or more of ITO, IZO, Ag, Al, IGZO, transparent conductive polymer, and the thickness of the anode layer 2 is set to 8-300nm; Above the anode layer 2 is a plurality of light-emitting structure layers 3; the number of light-emitting structure layers 3 includes at least two, for example two, three or four. Each light-emitting structure layer 3 includes a blue light-emitting layer 31, a green light-emitting layer 32 and a red light-emitting layer 33 stacked in the vertically upward direction, an intermediate transport layer 34 is provided between the blue light-emitting layer 31 and the green light-emitting layer 32, a hole layer 8 is provided between the anode layer 2 and the light-emitting structure layer 3, the hole layer 8 includes a hole injection layer 81 and a hole transport layer 82, an electron blocking layer 35 is provided between the hole transport layer 82 and the blue light-emitting layer 31, and an electron transport layer 36 is provided above the red light-emitting layer 33; A charge generation layer 9 is provided between any two of the light-emitting structure layers 3, the charge generation layer 9 includes an N-type charge generation layer 91 and a P-type charge generation layer 92.
[0025] A plurality of light-emitting structure layers 3 are provided above a cathode layer 4, wherein the material for manufacturing the cathode layer 4 can be selected from metal compounds, and the elements contained therein can be one or more of Yb, Mg, Ag, IZO, ITO, Al, Au, and the thickness is set to 1-40 nm.
[0026] A light extraction layer 5 and an encapsulation layer 6 are provided above the cathode layer 4, and the encapsulation layer 6 is manufactured by a thin film encapsulation process. The uppermost side is a color filter layer 7, which contains three light-emitting modules of R / G / B respectively. A charge generation layer 9 is provided between any two adjacent light-emitting structure layers 3, and the charge generation layer 9 comprises: An N-type charge generation layer 91 and a P-type charge generation layer 92.
[0027] The application also discloses a manufacturing process of the display panel, which comprises the following steps: A CMOS or TFT circuit is manufactured on the substrate 1 of Si or TFT, for driving the display panel to emit light. An anode layer 2 is manufactured, wherein the anode layer is selected to be a composite structure. The light-emitting structure layer 3 is evaporated by an evaporation process, and the light-emitting structure layer 3 is set to at least two. The cathode layer 4 and the light extraction layer 5 are manufactured. The encapsulation layer 6 is manufactured by a thin film encapsulation process. The color filter layer containing R / G / B modules is manufactured. Finally, the panel is cut and tested.
[0028] The application sets a comparative example, wherein the light-emitting structure layer 3 in the comparative example adopts a single-layer structure, and the anode layer 2 adopts a composite structure of metal and metal compound, and the structure on the anode layer 2 comprises HIL→HTL→B-Prime→EML-B→EML-G→EML-R→ETL→Cathode→CPL→encapsulation layer→color filter layer in sequence. HIL is a hole injection layer 81, HTL is a hole transport layer 82, B-Prime is an electron blocking layer 35, EML-B is a blue light-emitting layer 31, EML-G is a green light-emitting layer 32, EML-R is a red light-emitting layer 33, ETL is an electron transport layer, Cathode is a cathode layer 4, and CPL is a light extraction layer 5.
[0029] The embodiment 1 is modified on the basis of the comparative example as follows: 1. The light-emitting structure layer is designed to be at least two, and an N-type charge generation layer 91 and a P-type charge generation layer 92 are designed between any two light-emitting structure layers. 2. An ITL layer is introduced between the blue emitting layer 31 and the green emitting layer 32 as an intermediate transport layer 34. Compared with the traditional BGR device structure, the intermediate transport layer 34 introduced in this scheme can effectively improve the distribution of exciton recombination region, increase the exciton recombination probability of B / G device, improve B / G efficiency, effectively improve G / B display spectrum, and improve display color purity. The display panel structure in embodiment 1 is as follows: HIL→HTL→B-Prime→EML-B→ITL→EML-G→EML-R→ETL→n-CGL→p-CGL→HTL2→B-Prime→EML-B→ITL→EML-G→EML-R→ETL→Cathode→CPL. Among them, HTL is the hole transport layer 82, B-Prime is the electron blocking layer 35, EML-B is the blue emitting layer 31, ETL is the electron transport layer 36, ITL is the intermediate transport layer 34, EML-G is the green emitting layer 32, EML-R is the red emitting layer 33, Cathode is the cathode layer 4, CPL is the light extraction layer 5, n-CGL is the n-type charge generation layer 91, and P-CGL is the p-type charge generation layer 92. The hole injection layer 81, hole transport layer 81, and P-type charge generation layer 92 are made of one or more of poly(3,4)-ethylenedioxythiophene (PEDOT), polyaniline (PANI), and N,N'-dinaphthyl-N,N'-diphenylbenzidine (NPD), with a thickness of 5-140 nm; the electron blocking layer 35 and intermediate transport layer 34 are made of aromatic compounds with a thickness of 3-50 nm; the electron transport layer is formed using compounds, including but not limited to one or more of PBD, TAZ, spiro-PBD, BAlq, or SAlq. The thickness is 10~50nm; the N-type charge generation layer is an electron generation layer doped with an n-type dopant, and the n-type dopant is selected from one or more of Ag, Mg, Yb, Li, Al, Au, Ca, and Ba; the blue light-emitting layer 31, the green light-emitting layer 32, and the red light-emitting layer 33 are all composed of host materials and dopant materials, including but not limited to organic and inorganic materials, and the thickness is set to 10~50nm; the light extraction layer 5 is made of aromatic compounds or organic materials, inorganic materials, and metallic compounds with high refractive index, and the thickness is set to 40~200nm.
[0030] Furthermore, based on Example 1, the present invention provides Examples 2, 3, 4, 5, and 6, the difference being: In Example 2, the composite structure of the anode layer 2 is changed to a composite structure consisting of SiN, SiO, metal, and metal oxide, while the structure on the anode layer 2 is the same as in Example 1. In Example 3, the composite structure of the anode layer 2 was changed to a composite structure consisting of a nanograting structure, metal, and metal oxide, while the structure on the anode layer 2 was the same as in Example 1. In Example 4, the composite structure of the anode layer 2 is changed to a composite structure consisting of a composite coating, metal, and metal oxide, while the structure on the anode layer 2 is the same as in Example 1. In Example 5, the composite structure of the anode layer 2 was changed to a composite structure consisting of a novel conductive polymer, a metal, and a metal oxide, while the structure on the anode layer 2 was the same as in Example 1.
[0031] The difference between Example 6 and Example 1 is: The green luminescent layer 32 and the red luminescent layer 33 in the luminescent structure layer 3 are made of a novel perovskite luminescent material.
[0032] The data on the luminescence performance of the comparative examples (reference examples) and Examples 1-6 are shown in Table 1: Table 1
[0033] Meanwhile, the reflectivity data of anode 2 in some embodiments and comparative examples (reference examples) can be found in Table 2 and Fig. 3 As shown, the various schemes adopted in this application all include the technical solution of composite anode structure + three-color microcavity optimization, which can effectively improve the luminous efficiency and lifespan of the device and improve the performance requirements of the product.
[0034] Table 2
[0035] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this invention or its equivalents are included in this invention.
Claims
1. A display panel, characterized by, The display panel comprises: a substrate (1); an anode layer (2) disposed on the substrate (1); a plurality of light-emitting structure layers (3) stacked on the anode layer (2), each of the light-emitting structure layers (3) comprising a blue light-emitting layer (31), a green light-emitting layer (32) and a red light-emitting layer (33) stacked in sequence; a charge generation layer (9) disposed between any two adjacent light-emitting structure layers; a cathode layer (4) disposed on the plurality of light-emitting structure layers (3); wherein an intermediate functional layer (34) is disposed between the blue light-emitting layer (31) and the green light-emitting layer (32) in each of the light-emitting structure layers (3); the anode layer (2) adopts a composite structure.
2. The display panel of claim 1, wherein, The charge generation layer (9) comprises an N-type charge generation layer (91) and a P-type charge generation layer (92).
3. The display panel of claim 1, wherein, The composite structure comprises a metal material and a metal oxide material.
4. The display panel of claim 3, wherein, The composite structure further comprises at least one selected from a nanostructure layer, an insulating material layer and a conductive polymer layer.
5. The display panel of claim 1, wherein, A hole layer (8) is disposed between the anode layer (2) and the light-emitting structure layer (3) adjacent to the anode layer (2), and the hole layer (8) comprises a hole injection layer (81) and a hole transport layer (82) stacked in sequence.
6. The display panel of claim 5, wherein, An electron blocking layer (35) is disposed between the hole transport layer (82) and the blue light-emitting layer (31).
7. The display panel of claim 1, wherein, An electron transport layer (36) is disposed on each of the red light-emitting layers (33), and the display panel further comprises a light extraction layer (5) and an encapsulation layer (6) disposed on the cathode layer (4), and a color filter layer (7) disposed on the encapsulation layer (6).
8. The display panel of claim 1, wherein, At least one of the green light-emitting layer (31) and the red light-emitting layer (32) comprises a perovskite material.
9. A display device, characterized by comprising: The display panel comprises any one of claims 1-8.
10. A manufacturing method of a display panel, characterized by, The display panel comprises: forming an anode layer (2) on a substrate (1), wherein the anode layer (2) adopts a composite structure; forming a plurality of light-emitting structure layers (3) on the anode layer (2), and forming a charge generation layer (9) between any two adjacent light-emitting structure layers (3); wherein each of the light-emitting structure layers (3) comprises a blue light-emitting layer (31), an intermediate functional layer (34), a green light-emitting layer (32) and a red light-emitting layer (33) formed in sequence; forming a cathode layer (4) on the plurality of light-emitting structure layers (3).