CN110600623B - Electroluminescent device and preparation method thereof - Google Patents
Electroluminescent device and preparation method thereof Download PDFInfo
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- CN110600623B CN110600623B CN201810608410.2A CN201810608410A CN110600623B CN 110600623 B CN110600623 B CN 110600623B CN 201810608410 A CN201810608410 A CN 201810608410A CN 110600623 B CN110600623 B CN 110600623B
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K50/00—Organic light-emitting devices
- H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
- H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
- H10K50/115—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers comprising active inorganic nanostructures, e.g. luminescent quantum dots
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- H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
- H10K59/10—OLED displays
- H10K59/12—Active-matrix OLED [AMOLED] displays
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- H—ELECTRICITY
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- H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
- H10K59/10—OLED displays
- H10K59/12—Active-matrix OLED [AMOLED] displays
- H10K59/121—Active-matrix OLED [AMOLED] displays characterised by the geometry or disposition of pixel elements
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Abstract
The invention provides an electroluminescent device, which comprises a substrate, and at least one quantum dot electroluminescent unit and at least one organic electroluminescent unit which are arranged on the substrate, wherein the quantum dot electroluminescent unit comprises a first anode and a first cathode which are oppositely arranged, a quantum dot luminescent layer arranged between the first anode and the first cathode, and a first electron transmission layer arranged between the quantum dot luminescent layer and the first cathode; the organic electroluminescent unit comprises a second anode and a second cathode which are oppositely arranged, and an organic light-emitting layer arranged between the second anode and the second cathode; a second electron transport layer is arranged between the first electron transport layer and the first cathode of the quantum dot electroluminescent unit, and a third electron transport layer is arranged between the organic light emitting layer and the second cathode of the organic electroluminescent unit.
Description
Technical Field
The invention belongs to the technical field of luminous display, and particularly relates to an electroluminescent device and a preparation method thereof.
Background
Because Quantum dots have the characteristics of adjustable size, narrow Light Emitting line width, high Light Emitting efficiency and the like, Quantum Dot Light Emitting diodes (QLEDs) using Quantum dots as Light Emitting layers become the next generation of display and solid state lighting Light sources with great potential. Quantum dot electroluminescence has advantages of good color purity, high luminescence quantum efficiency, fast response speed, and the like, and has attracted much attention in recent years. After years of research and development, the external quantum efficiency of the current highest red and green QLED is over or close to 20% from the publicly reported literature data, which indicates that the internal quantum efficiency of the red and green quantum dot light-emitting diode is actually close to the theoretical limit. However, the current electro-optic conversion efficiency of the blue quantum dot light emitting diode, which is one of the essential three primary colors for color display, is much lower than that of the red and green quantum dot light emitting diode, thereby limiting the application of the quantum dot light emitting diode in color display.
In addition, the service life of the quantum dot light-emitting diode devices with three colors of red, green and blue is also greatly different. From the publicly reported literature data, the initial luminance of the red quantum dot light emitting diode device is 100cd/m2Under working conditions, the half-brightness service life exceeds 10 ten thousand hours or even longer; however, the half-brightness life of green and blue quantum dot light emitting diode devices is far lower than that of red devices, especially quantum dot light emitting diode devices, and the half-life reported in public only reaches dozens to hundreds of hours, and there is a great difference from practical level.
Technologies based on organic light emitting materials, such as electroluminescent (OLED) materials and device structures, have been developed for almost thirty years, and compared with QLEDs, the performance of some organic electroluminescent materials is better than that of quantum dots, such as higher light emitting efficiency or longer lifetime. Therefore, the high-performance organic light-emitting material can be used for making up the performance defects of the quantum dots and the quantum dot light-emitting diode device. However, in the hybrid electroluminescent device, the organic electroluminescent display unit needs to adopt the structure and process of the electron transport layer of the evaporated organic material due to the requirement of process compatibility, and the efficiency of the quantum dot electroluminescent device is reduced due to the electron transport layer formed by the existing evaporated organic material.
Disclosure of Invention
The invention aims to provide an electroluminescent device and a preparation method thereof, and aims to solve the problems of low luminous efficiency and short service life of the conventional quantum dot light-emitting diode device.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides an electroluminescent device, which comprises a substrate, and at least one quantum dot electroluminescent unit and at least one organic electroluminescent unit which are arranged on the substrate,
the quantum dot electroluminescent unit comprises a first anode and a first cathode which are oppositely arranged, a quantum dot light-emitting layer arranged between the first anode and the first cathode, and a first electron transport layer arranged between the quantum dot light-emitting layer and the first cathode;
the organic electroluminescent unit comprises a second anode and a second cathode which are oppositely arranged, and an organic light-emitting layer arranged between the second anode and the second cathode;
a second electron transport layer is arranged between the first electron transport layer and the first cathode of the quantum dot electroluminescent unit, and a third electron transport layer is arranged between the organic light emitting layer and the second cathode of the organic electroluminescent unit;
wherein the first anode and the second anode are disposed on the substrate, or the first cathode and the second cathode are disposed on the substrate;
the materials of the first anode and the second anode are the same or different, the materials of the first cathode and the second cathode are the same or different, the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride.
A method for preparing an electroluminescent device comprises the following steps:
providing a substrate, preparing a cathode and a pixel defining layer on the substrate, forming a pixel groove formed by surrounding the cathode as a bottom and the pixel defining layer, and presetting a quantum dot light-emitting area and an organic light-emitting area;
preparing a second electron transport layer on the surface of the cathode of the quantum dot light-emitting region, and preparing a first electron transport layer on the second electron transport layer; preparing a third electron transport layer on the surface of the cathode of the organic light-emitting region, wherein the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride;
preparing a quantum dot light-emitting layer on the surface of the first electron transport layer, preparing a first anode on the quantum dot light-emitting layer, preparing an organic light-emitting layer on the surface of the third electron transport layer, and preparing a second anode on the organic light-emitting layer, wherein the quantum dot light-emitting layer is arranged in the quantum dot light-emitting area, and the organic light-emitting layer is arranged in the organic light-emitting area.
A method for preparing an electroluminescent device comprises the following steps:
providing a substrate, preparing an anode and a pixel defining layer on the substrate, forming a pixel groove formed by surrounding the anode as a bottom and the pixel defining layer, and presetting a quantum dot light-emitting area and an organic light-emitting area;
preparing a quantum dot light-emitting layer on the surface of the anode of the quantum dot light-emitting area, and preparing an organic light-emitting layer on the surface of the anode of the organic light-emitting area;
preparing a first electron transport layer on the surface of the quantum dot light-emitting layer, and preparing a second electron transport layer on the surface of the first electron transport layer; preparing a third electron transport layer on the surface of the organic light-emitting layer; the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride;
and preparing a first cathode on the surface of the second electron transport layer, and preparing a second cathode on the surface of the third electron transport layer.
The invention provides a luminescent device based on quantum dot electroluminescence and organic electroluminescence, which can give full play to the advantages of quantum dots and organic materials and realize photoelectric display with more excellent performance. Specifically, firstly, the electroluminescent device provided by the invention adopts a combined mixed light-emitting mode of organic electroluminescence and quantum dot electroluminescence, so that the comprehensive display performance of the display can be further improved, and particularly, the light-emitting efficiency and the service life of weak electroluminescent units such as blue light-emitting electroluminescent diodes are improved. In addition, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the first electron transport layer is matched, so that the luminous efficiency of the quantum dot light-emitting device can be improved, and the comprehensive display performance of the display can be further improved. In addition, the quantum dot electroluminescent unit simultaneously comprises the first electron transport layer and the second electron transport layer, and the composite electron transport layer structure based on the inorganic nanoparticle electron transport layer and the organic material electron transport layer is adopted, so that the high efficiency of quantum dot electroluminescence can be maintained, and the process compatibility of the organic electroluminescent unit is considered.
The preparation method of the electroluminescent device provided by the invention only needs to adjust the type of the luminescent layer material on the one hand and the type of the electron transport layer on the other hand on the basis of the preparation process of the conventional electroluminescent device, so that different luminescent units correspond to different electron transport layer systems. The method provided by the invention has good process compatibility and simple process, can reduce the manufacturing cost, and most importantly, can obtain the electroluminescent device with high luminous efficiency.
Drawings
Fig. 1 is a schematic structural view of an electroluminescent device provided in embodiment 1 of the present invention;
fig. 2 is a schematic structural view of an electroluminescent device provided in embodiment 2 of the present invention;
fig. 3 is a schematic structural diagram of an electroluminescent device provided in embodiment 3 of the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
The embodiment of the invention provides an electroluminescent device, which comprises a substrate, and at least one quantum dot electroluminescent unit and at least one organic electroluminescent unit which are arranged on the substrate,
the quantum dot electroluminescent unit comprises a first anode and a first cathode which are oppositely arranged, a quantum dot light-emitting layer arranged between the first anode and the first cathode, and a first electron transport layer arranged between the quantum dot light-emitting layer and the first cathode;
the organic electroluminescent unit comprises a second anode and a second cathode which are oppositely arranged, and an organic light-emitting layer arranged between the second anode and the second cathode;
a second electron transport layer is arranged between the first electron transport layer and the first cathode of the quantum dot electroluminescent unit, and a third electron transport layer is arranged between the organic light emitting layer and the second cathode of the organic electroluminescent unit;
wherein the first anode and the second anode are disposed on the substrate, or the first cathode and the second cathode are disposed on the substrate;
the materials of the first anode and the second anode are the same or different, the materials of the first cathode and the second cathode are the same or different, the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride.
The embodiment of the invention provides a luminescent device based on quantum dot electroluminescence and organic electroluminescence, which can give full play to the advantages of quantum dots and organic materials and realize photoelectric display with more excellent performance. Specifically, firstly, the electroluminescent device provided by the invention adopts a combined mixed light-emitting mode of organic electroluminescence and quantum dot electroluminescence, so that the comprehensive display performance of the display can be further improved, and particularly, the light-emitting efficiency and the service life of weak electroluminescent units such as blue light-emitting electroluminescent diodes are improved. In addition, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the first electron transport layer is matched, so that the luminous efficiency of the quantum dot light-emitting device can be improved, and the comprehensive display performance of the display can be further improved. In addition, the quantum dot electroluminescent unit simultaneously comprises the first electron transport layer and the second electron transport layer, and the composite electron transport layer structure based on the inorganic nanoparticle electron transport layer and the organic material electron transport layer is adopted, so that the high efficiency of quantum dot electroluminescence can be maintained, and the process compatibility of the organic electroluminescent unit is considered.
In the embodiment of the present invention, the electroluminescent device includes at least one quantum dot electroluminescent unit and at least one organic electroluminescent unit, which are understood that materials of a luminescent layer in an electroluminescent display unit are not completely the same, and include a quantum dot luminescent material and an organic luminescent material, that is, the luminescent material in the quantum dot electroluminescent unit is a quantum dot material, and the luminescent material in the organic electroluminescent unit is an organic material.
The electroluminescent device can at least select any one color of luminescent device as the quantum dot electroluminescent unit in principle, and can also at least select any one color of luminescent device as the organic electroluminescent unit. Preferably, the electroluminescent device comprises a blue electroluminescent display unit, and the blue electroluminescent display unit is an organic electroluminescent unit, so that the luminous efficiency and the service life of the blue electroluminescent device are improved.
Specifically, in the embodiment of the present invention, the materials of the first anode and the second anode are the same or different, and the materials of the first cathode and the second cathode are the same or different. Preferably, in order to improve material compatibility and further improve device stability, and to simplify a process flow, the materials of the first anode and the second anode are the same, that is, the quantum dot electroluminescent unit and the organic electroluminescent unit share an anode; the first cathode and the second cathode are made of the same material, namely the quantum dot electroluminescent unit and the organic electroluminescent unit share a cathode.
Preferably, the electroluminescent device may further include one or more functional layers such as a hole transport layer, a hole injection layer, an electron blocking layer, a hole blocking layer, and an electron injection layer. Wherein the content of the first and second substances,
the substrate provided by the embodiment of the invention is arranged at one end of the anode or the cathode and is used for bearing the whole electroluminescent device. Specifically, the first anode and the second anode are disposed on the substrate, or the first cathode and the second cathode are disposed on the substrate.
A hole transport layer is located between the (quantum dot or organic) light emitting layer and the anode;
a hole injection layer is located between the hole transport layer and the anode or, in the case where no hole transport layer is provided, between the (quantum dot or organic) light emitting layer and the anode; the hole injection layer can further improve the luminous efficiency of each luminous unit so as to further reduce the power consumption.
An electron blocking layer is located between the (quantum dot or organic) light emitting layer and the hole transport layer, or in the case where the hole transport layer is not provided, a hole injection layer is located between the (quantum dot or organic) light emitting layer and the anode;
the hole blocking layer is positioned between the (quantum dot or organic) light emitting layer and the electron transport layer, or between the (quantum dot or organic) light emitting layer and the cathode without the electron transport layer;
the electron injection layer is located between the electron transport layer and the cathode, or in case no electron transport layer is provided, the hole blocking layer is located between the (quantum dot or organic) light emitting layer and the cathode.
In an embodiment of the present invention, the electroluminescent device further includes a pixel defining layer for separating adjacent light emitting cells. That is, adjacent electroluminescent display units are separated by a pixel defining layer, and the area where the light emitting unit is located is a pixel area of the display device, which can be understood as that one light emitting unit constitutes one pixel point. The pixel defining layer can also limit the material solution to accurately flow into a designated light-emitting unit sub-pixel area in the process of solution method process manufacturing, so that the reduction of light-emitting purity caused by color cross is prevented.
On the basis of the above structure, the material of the first electron transport layer is selected from metal oxides.
In the embodiment of the present invention, it is preferable that the alkali metal fluoride used as the material of the second and third electron transport layers is at least one selected from lithium fluoride (LiF), sodium fluoride (NaF), potassium fluoride (KF), rubidium fluoride (RbF), and cesium fluoride (CsF). Preferably, the alkaline earth metal fluoride used as the material of the second and third electron transport layers is selected from calcium fluoride (CaF)2) Strontium fluoride (SrF)2) And barium fluoride (BaF 2). The preferable alkali metal fluoride and alkaline earth metal fluoride have lower work functions, have more matched energy level structures with organic luminescent materials, and can effectively balance carriers of a quantum dot luminescent unit by matching with metal oxide, thereby being beneficial to improving the luminescent efficiency.
Preferably, the metal oxide may be selected from zinc oxide (ZnO), magnesium oxide (MgO), tin oxide (SnO)2) It can also be selected from zinc magnesium oxide (Zn)xMgyOx+y) Zinc tin oxide (Zn)xSnyOx+2y) Zinc aluminum oxide (Zn)2xAl2yO2x+3y) Zinc calcium oxide (Zn)xCayOx+y) Etc., wherein x + y is 1. More preferably ZnO and zinc magnesium oxide (Zn)xMgyOx+y) A nanoparticle material. It should be understood that the above-described embodiments,in the embodiment of the present invention, the materials of the second electron transport layer and the third electron transport layer may be the same or different.
In the embodiment of the present invention, the thickness of the second transmission layer is preferably 2 to 16nm, and more preferably 3 to 10 nm. The thickness of the third transport layer is 2-16nm, more preferably 3-10 nm. If the thicknesses of the second transmission layer and the third transmission layer are too thin, the film is difficult to form and the transmission layer cannot be used; if the thickness of the second transport layer and the third transport layer is too thick, since electron injection is performed by tunneling or dipole formation, etc., and the alkali metal fluoride and the alkaline earth metal fluoride are insulating materials themselves, too thick thin films may cause difficulty in electron injection.
The substrate is preferably a transparent substrate, and may be a glass substrate or a flexible substrate.
The luminescent material is selected according to the type of the luminescent layer, and when the luminescent layer is a quantum dot luminescent layer, the quantum dot luminescent material is selected. Specifically, the quantum dot luminescent material may be selected from group II-IV compound semiconductors including, but not limited to, CdS, CdSe, CdS/ZnS, CdSe/CdS/ZnS; and may also be selected from group III-V or IV-VI compound semiconductors including, but not limited to, GaAs, InP, PbS/ZnS, PbSe/ZnS; the quantum dot light-emitting material can also be selected from semiconductor nanocrystals of I-III-VI2 groups and the like, and the quantum dot light-emitting material can be of a uniform mixing type, a gradient mixing type, a core-shell type or a combined type. The quantum dot light-emitting material may contain a dopant, and the doping method may be self-doping.
When the light emitting layer is an organic light emitting layer, a conventional organic light emitting material is selected. Preferably, a solution-processed organic light emitting material is used, so that a film can be formed during the preparation process by a solution process such as inkjet printing. For example, when the blue electroluminescent display unit is an organic electroluminescent display unit, the material of the blue organic light emitting layer in the blue electroluminescent display unit is selected from stilbene (Distyrylarylene),
Chrysenes, pyrenes, anthracenes, and perylenes.
The hole transport material can be selected from organic transport materials such as poly-TPD, TFB and the like, NiO and MoO3And inorganic transport materials and composites thereof. The hole transport material comprises poly-TPD, TFB, NiO and MoO3But are not limited to these materials.
Materials of the hole injection layer include, but are not limited to, PEDOT: PSS.
The cathode material is a metal material including but not limited to metals such as Al, Ag, Ca, Mg, etc., and may be an alloy, preferably the most commonly used alloys of Al, Ag and Mg: Ag.
The electroluminescent device provided by the embodiment of the invention can be prepared by the following method.
The embodiment of the invention also provides a preparation method of the electroluminescent device.
As a specific embodiment, the method for manufacturing the electroluminescent device comprises the following steps:
s01, providing a substrate, preparing a cathode and a pixel defining layer on the substrate, forming a pixel groove formed by surrounding the cathode as a bottom and the pixel defining layer, and presetting a quantum dot light-emitting area and an organic light-emitting area;
s02, preparing a second electron transport layer on the surface of the cathode of the quantum dot light emitting region, and preparing a first electron transport layer on the second electron transport layer; preparing a third electron transport layer on the surface of the cathode of the organic light-emitting region, wherein the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride;
s03, preparing a quantum dot light-emitting layer on the surface of the first electron transport layer, preparing a first anode on the quantum dot light-emitting layer, preparing an organic light-emitting layer on the surface of the third electron transport layer, and preparing a second anode on the organic light-emitting layer, wherein the quantum dot light-emitting layer is arranged in the quantum dot light-emitting area, and the organic light-emitting layer is arranged in the organic light-emitting area.
The materials for the various layers are selected as described above and will not be described in further detail herein for economy of disclosure.
Specifically, in step S01, the cathode and the pixel defining layer are formed on the substrate by a conventional method. The quantum dot light-emitting area and the organic light-emitting area are preset according to product requirements or design requirements. The cathode is divided into a first cathode where the quantum dot light emitting area is located and a second cathode where the organic light emitting area is located.
In the step S02, an electron transport layer is formed on the surface of the cathode in the pixel groove, specifically, a second electron transport layer is formed on the surface of the cathode in the quantum dot light emitting region, and a first electron transport layer is formed on the second electron transport layer; and preparing a third electron transport layer on the surface of the cathode of the organic light-emitting region. The first electron transmission layer is realized by adopting a solution processing method, preferably an ink-jet printing mode, and the second electron transmission layer and the third electron transmission layer are realized by adopting a vacuum true plating mode. The first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride.
In step S03, different light-emitting materials are deposited according to the types of the electroluminescent units. And preparing a quantum dot light-emitting layer on the surface of the first electron transport layer, and preparing an organic light-emitting layer on the surface of the third electron transport layer, preferably by adopting a solution processing method.
And preparing an anode on the luminescent layer, specifically, preparing a first anode on the quantum dot luminescent layer, and preparing a second anode on the organic luminescent layer, wherein the vacuum plating mode is preferably adopted.
Further, before the anode is prepared, a hole transport layer is preferably prepared on the light emitting layer by a solution processing method or a vacuum evaporation process.
As another specific embodiment, the method for manufacturing the electroluminescent device includes the steps of:
E01. providing a substrate, preparing an anode and a pixel defining layer on the substrate, forming a pixel groove formed by surrounding the anode as a bottom and the pixel defining layer, and presetting a quantum dot light-emitting area and an organic light-emitting area;
E02. preparing a quantum dot light-emitting layer on the surface of the anode of the quantum dot light-emitting area, and preparing an organic light-emitting layer on the surface of the anode of the organic light-emitting area;
E03. preparing a first electron transport layer on the surface of the quantum dot light-emitting layer, and preparing a second electron transport layer on the surface of the first electron transport layer; preparing a third electron transport layer on the surface of the organic light-emitting layer; the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride;
E04. and preparing a first cathode on the surface of the second electron transport layer, and preparing a second cathode on the surface of the third electron transport layer.
Specifically, in step E01, the anode and the pixel defining layer on the substrate can be prepared by conventional methods, and the anode is preferably prepared by vacuum plating. The quantum dot light-emitting area and the organic light-emitting area are preset according to product requirements or design requirements. The anode is divided into a first anode where the quantum dot light emitting area is located and a second anode where the organic light emitting area is located.
In step E02, a light-emitting layer is formed on the surface of the anode in the pixel groove, preferably by a solution processing method. At this time, different light emitting materials may be deposited according to different types of electroluminescent units. Specifically, a quantum dot light emitting layer is formed on the surface of the anode of the quantum dot light emitting region, and an organic light emitting layer is formed on the surface of the anode of the organic light emitting region. Further, before the light-emitting layer is formed, it is preferable to form a hole transport layer on the surface of the anode by a solution processing method or a vacuum evaporation process.
In the step E03, an electron transport layer is prepared on the surface of the light emitting layer, specifically, a first electron transport layer is prepared on the surface of the quantum dot light emitting layer, and a second electron transport layer is prepared on the surface of the first electron transport layer; and preparing a third electron transport layer on the surface of the organic light-emitting layer, wherein the first electron transport layer and the second electron transport layer are made of different materials. The first electron transmission layer is realized by adopting a solution processing method, preferably an ink-jet printing mode, and the second electron transmission layer and the third electron transmission layer are realized by adopting a vacuum true plating mode. Preferably, a second electron transport layer is prepared between the first electron transport layer and the quantum dot light-emitting layer by a solution processing method to form a composite electron transport layer. The first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride.
In the step E04, a first cathode is prepared on the surface of the second electron transport layer, and a second cathode is prepared on the surface of the third electron transport layer, preferably by vacuum plating.
The preparation method of the electroluminescent device provided by the invention only needs to adjust the type of the luminescent layer material on the one hand and the type of the electron transport layer on the other hand on the basis of the preparation process of the conventional electroluminescent device, so that different luminescent units correspond to different electron transport layer systems. The method provided by the invention has good process compatibility and simple process, can reduce the manufacturing cost, and most importantly, can obtain the electroluminescent device with high luminous efficiency.
The following description will be given with reference to specific examples.
Example 1
An electroluminescent device, as shown in fig. 1, includes a substrate 300 (glass substrate), an anode 110(ITO transparent anode) and a pixel defining layer 310(PDL) for separating adjacent light emitting pixel units provided on the substrate 300, a hole injection layer 120 provided on the anode 110, a hole transport layer 130 provided on the hole injection layer 120, a light emitting layer provided on the hole transport layer 130, wherein 210, 220, 230 respectively denote a blue light emitting layer, a green light emitting layer, a red light emitting layer, and 210 is a blue organic light emitting layer; 220 is a green quantum dot light emitting layer; reference numeral 230 denotes a red quantum dot light-emitting layer, a first electron transport layer 150 provided on the quantum dot light-emitting layer, a second electron transport layer 155 provided on the organic light-emitting layer and the first electron transport layer 150, and a cathode 160 provided on the second electron transport layer 155.
The preparation method of the electroluminescent device comprises the following steps:
providing a substrate with ITO electrodes and PDL pixel defining layers prepared in advance,
preparing the hole injection layer 120 on the substrate by ink-jet printing and preparing ink-jet printing, and printing all pixels completely; preparing a hole injection layer 130 by ink-jet printing on the hole injection layer 120, and printing all pixels; ink-jet printing a red quantum dot light emitting layer 220, a green quantum dot light emitting layer 230, and a blue organic light emitting layer 210 on the hole injection layer 130;
ink-jet printing a first electron transport layer 150 on the surfaces of the green quantum dots 220 and the red quantum dots 230; the second electron transport layer 155 is evaporated in vacuum by using Open-Mask, and all pixels are evaporated;
the Open-Mask suitable for the cathode region is replaced, and the metal cathode 160 is prepared by vacuum evaporation.
Example 2
An electroluminescent device, as shown in fig. 2, includes a substrate 300 (glass substrate), an anode 110(ITO transparent anode) and a pixel defining layer 310(PDL) for separating adjacent light emitting pixel units provided on the substrate 300, a hole injection layer 120 provided on the anode 110, a hole transport layer 130 provided on the hole injection layer 120, a light emitting layer provided on the hole transport layer 130, wherein 210, 215, 230 denote a blue light emitting layer, a green light emitting layer, a red light emitting layer, and 210 is a blue organic light emitting layer, respectively; 215 a green organic light emitting layer; 230 is a red quantum dot light emitting layer; a first electron transport layer 150 provided on the quantum dot light emitting layer, a second electron transport layer 155 provided on the organic light emitting layer and the first electron transport layer 150, and a cathode 160 provided on the second electron transport layer 155.
The preparation method of the electroluminescent device comprises the following steps:
providing a substrate with ITO electrodes and PDL pixel defining layers prepared in advance,
preparing the hole injection layer 120 on the substrate by ink-jet printing and preparing ink-jet printing, and printing all pixels completely; preparing a hole injection layer 130 by ink-jet printing on the hole injection layer 120, and printing all pixels; ink-jet printing a red quantum dot light emitting layer 220, a green organic light emitting layer 215, and a blue organic light emitting layer 210 on the hole injection layer 130;
on the surface of the red quantum dot light-emitting layer 220, ink-jet printing is performed on the first electron transport layer 150; the second electron transport layer 155 is evaporated in vacuum by using Open-Mask, and all pixels are evaporated;
the Open-Mask suitable for the cathode region is replaced, and the metal cathode 160 is prepared by vacuum evaporation.
Example 3
An electroluminescent device, as shown in fig. 3, includes a substrate 300 (glass substrate), an anode 110(ITO transparent anode) and a pixel defining layer 310(PDL) for separating adjacent light emitting pixel units provided on the substrate 300, a hole injection layer 120 provided on the anode 110, a hole transport layer 130 provided on the hole injection layer 120, a light emitting layer provided on the hole transport layer 130, wherein 210, 220, 235 represent a blue light emitting layer, a green light emitting layer, a red light emitting layer, and 210 is a blue organic light emitting layer, respectively; 220 is a green quantum dot light emitting layer; 235 is a red organic light emitting layer; a first electron transport layer 150 provided on the quantum dot light emitting layer, a second electron transport layer 155 provided on the organic light emitting layer and the first electron transport layer 150, and a cathode 160 provided on the second electron transport layer 155.
The preparation method of the electroluminescent device comprises the following steps:
providing a substrate with ITO electrodes and PDL pixel defining layers prepared in advance,
preparing the hole injection layer 120 on the substrate by ink-jet printing and preparing ink-jet printing, and printing all pixels completely; preparing a hole injection layer 130 by ink-jet printing on the hole injection layer 120, and printing all pixels; ink-jet printing a blue organic light emitting layer 210, a green quantum dot light emitting layer 220, a red organic light emitting layer 235 on the hole injection layer 130;
ink-jet printing a first electron transport layer 150 on the surface of the green quantum dot light-emitting layer 220; the second electron transport layer 155 is evaporated in vacuum by using Open-Mask, and all pixels are evaporated;
the Open-Mask suitable for the cathode region is replaced, and the metal cathode 160 is prepared by vacuum evaporation.
The results show that example 1 makes full use of the advantages of pure red and green quantum dot light emission colors and longer blue organic electroluminescent life than blue quantum dots to combine to obtain a display device with more stable performance than a quantum dot electroluminescent display using quantum dots in all three colors.
Embodiment 2 makes full use of the high electroluminescent efficiency, pure color and good reliability of red quantum dots, and realizes higher performance mixed luminescent display by cooperating with high-efficiency blue and green organic electroluminescence.
The green quantum dots are adopted for emitting light in embodiment 3, so that the green emitting color purity can be further improved.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (9)
1. An electroluminescent device comprising a substrate, and at least one quantum dot electroluminescent unit and at least one organic electroluminescent unit disposed on the substrate,
the quantum dot electroluminescent unit comprises a first anode and a first cathode which are oppositely arranged, a quantum dot light-emitting layer arranged between the first anode and the first cathode, and a first electron transport layer arranged between the quantum dot light-emitting layer and the first cathode;
the organic electroluminescent unit comprises a second anode and a second cathode which are oppositely arranged, and an organic light-emitting layer arranged between the second anode and the second cathode;
a second electron transport layer is arranged between the first electron transport layer and the first cathode of the quantum dot electroluminescent unit, and only a third electron transport layer is arranged between the organic light emitting layer and the second cathode of the organic electroluminescent unit;
wherein the first anode and the second anode are disposed on the substrate, or the first cathode and the second cathode are disposed on the substrate;
the materials of the first anode and the second anode are the same or different, the materials of the first cathode and the second cathode are the same or different, the first electron transport layer at least contains one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, the thickness of the second electron transport layer is 2-16nm, and the thickness of the third electron transport layer is 2-16 nm.
2. An electroluminescent device as claimed in claim 1, characterized in that the material of the first electron transport layer is selected from metal oxides.
3. The electroluminescent device of claim 1, wherein the alkali metal fluoride is selected from at least one of lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, and cesium fluoride.
4. The electroluminescent device of claim 1, wherein the alkaline earth metal fluoride is selected from at least one of calcium fluoride, strontium fluoride, and barium fluoride.
5. An electroluminescent device as claimed in any one of claims 1 to 4, wherein the metal oxide is selected from at least one of zinc oxide, magnesium oxide, tin oxide, zinc magnesium oxide, zinc tin oxide, zinc aluminium oxide, zinc calcium oxide nanomaterial.
6. An electroluminescent device as claimed in any one of claims 1 to 4, wherein the first anode and the second anode are the same and the first cathode and the second cathode are the same.
7. An electroluminescent device as claimed in any one of claims 1 to 4, characterized in that the electroluminescent device further comprises a pixel-defining layer for separating adjacent light-emitting cells.
8. A method for preparing an electroluminescent device is characterized by comprising the following steps:
providing a substrate, preparing a cathode and a pixel defining layer on the substrate, forming a pixel groove formed by surrounding the cathode as a bottom and the pixel defining layer, and presetting a quantum dot light-emitting area and an organic light-emitting area;
preparing a second electron transport layer on the surface of the cathode of the quantum dot light-emitting region, and preparing a first electron transport layer on the surface of the second electron transport layer; preparing a third electron transport layer on the surface of the cathode of the organic light-emitting region, wherein the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride;
preparing a quantum dot light-emitting layer on the surface of the first electron transport layer, preparing a first anode on the quantum dot light-emitting layer, preparing an organic light-emitting layer on the surface of the third electron transport layer, and preparing a second anode on the organic light-emitting layer, wherein the quantum dot light-emitting layer is arranged in the quantum dot light-emitting area, and the organic light-emitting layer is arranged in the organic light-emitting area.
9. A method for preparing an electroluminescent device is characterized by comprising the following steps:
providing a substrate, preparing an anode and a pixel defining layer on the substrate, forming a pixel groove formed by surrounding the anode as a bottom and the pixel defining layer, and presetting a quantum dot light-emitting area and an organic light-emitting area;
preparing a quantum dot light-emitting layer on the surface of the anode of the quantum dot light-emitting area, and preparing an organic light-emitting layer on the surface of the anode of the organic light-emitting area;
preparing a first electron transport layer on the surface of the quantum dot light-emitting layer, and preparing a second electron transport layer on the surface of the first electron transport layer; preparing a third electron transport layer on the surface of the organic light-emitting layer; the first electron transport layer contains at least one metal oxide, the second electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride, and the third electron transport layer contains at least one of alkali metal fluoride and alkaline earth metal fluoride;
and preparing a first cathode on the surface of the second electron transport layer, and preparing a second cathode on the surface of the third electron transport layer.
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| CN112331789B (en) * | 2019-12-30 | 2023-02-17 | 广东聚华印刷显示技术有限公司 | Electroluminescent device |
| CN112331790A (en) * | 2019-12-31 | 2021-02-05 | 广东聚华印刷显示技术有限公司 | Light emitting device, manufacturing method thereof and display device |
| CN111129332A (en) * | 2019-12-31 | 2020-05-08 | 深圳市华星光电半导体显示技术有限公司 | OLED display panel |
| CN112331699A (en) * | 2019-12-31 | 2021-02-05 | 广东聚华印刷显示技术有限公司 | Light emitting device, manufacturing method thereof and display device |
| CN113937227B (en) * | 2020-07-14 | 2022-05-31 | Tcl科技集团股份有限公司 | Light emitting device and method of manufacturing the same |
| WO2023092537A1 (en) * | 2021-11-29 | 2023-06-01 | 京东方科技集团股份有限公司 | Light-emitting device and method for manufacturing same, and display substrate and display apparatus |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103765623A (en) * | 2011-08-22 | 2014-04-30 | 默克专利有限公司 | Organic electroluminescence device |
| CN105304681A (en) * | 2015-10-19 | 2016-02-03 | Tcl集团股份有限公司 | Electroluminescent display with organic and inorganic mixed luminescent layer and preparation method of display |
| CN106601923A (en) * | 2016-12-19 | 2017-04-26 | 华南理工大学 | Full-color display component for organic and inorganic quantum dot hybridization and preparing method thereof |
-
2018
- 2018-06-13 CN CN201810608410.2A patent/CN110600623B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103765623A (en) * | 2011-08-22 | 2014-04-30 | 默克专利有限公司 | Organic electroluminescence device |
| CN105304681A (en) * | 2015-10-19 | 2016-02-03 | Tcl集团股份有限公司 | Electroluminescent display with organic and inorganic mixed luminescent layer and preparation method of display |
| CN106601923A (en) * | 2016-12-19 | 2017-04-26 | 华南理工大学 | Full-color display component for organic and inorganic quantum dot hybridization and preparing method thereof |
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