Light-emitting device, display panel and display device

Abstract

The invention discloses a light-emitting device, a display panel and a display device. The light-emitting device comprises a hole injection layer, a first light-emitting layer, an electron generation layer, a hole generation layer, a second light-emitting layer and an electron injection layer which are stacked, the light-emitting device comprises a first color light-emitting area and a second color light-emitting area, and a hole generation layer located in the first color light-emitting area is in non-electrical connection with a hole generation layer located in the second color light-emitting area. In the light-emitting device provided by the invention, the hole generation layer in the first color light-emitting region and the hole generation layer in the second color light-emitting region are not electrically conducted, so that current streaming between the hole generation layer in the first color light-emitting region and the hole generation layer in the second color light-emitting region is prevented; the problem of transverse leakage current in the device structure is prevented, the display crosstalk problem caused by the transverse leakage current during low-gray-scale display of the light-emitting device can be remarkably improved, and the display effect is improved.

Description

Technical Field

[0001] This invention belongs to the field of display technology, specifically relating to a light-emitting device, a display panel, and a display apparatus. Background Technology

[0002] In recent years, Organic Light Emitting Diodes (OLEDs) have gradually gained more attention as a new type of flat panel display. Due to their characteristics such as active light emission, high brightness, high resolution, wide viewing angle, fast response speed, low power consumption, and flexibility, they have become a popular mainstream display product in the market. As products continue to evolve, customers demand increasingly higher resolution and lower power consumption, requiring the development of high-efficiency, low-voltage, and long-life devices. OLED stacked devices combine multiple light-emitting units of the same color through a charge generation layer, thereby increasing the overall device's luminous efficiency to 1.5-2 times that of a single light-emitting unit. At the same brightness, the device's lifespan can be increased to more than 3 times the original level, making them widely used in display panels, automotive products, lighting, and other fields requiring long-life light-emitting devices. While OLED stacked devices are increasingly valued for their excellent stability and lifespan, compared to traditional device structures, they also have drawbacks that make it difficult to meet performance requirements. Summary of the Invention

[0003] The purpose of this invention is to provide a light-emitting device, a display panel, and a display apparatus to solve the problem of lateral leakage current in the OLED stacked device structure.

[0004] In a first aspect, embodiments of the present invention provide a light-emitting device, comprising:

[0005] The stacked layers are a hole injection layer, a first light-emitting layer, an electron generation layer, a hole generation layer, a second light-emitting layer, and an electron injection layer.

[0006] The light-emitting device includes a first color light-emitting region and a second color light-emitting region, and the hole-generating layer located in the first color light-emitting region and the hole-generating layer located in the second color light-emitting region are non-electrically connected.

[0007] Optionally, the electron generating layer located in the first color emitting region is non-electrically connected to the electron generating layer located in the second color emitting region.

[0008] Optionally, the light-emitting device includes a third color light-emitting region, and the hole-generating layer located in the second color light-emitting region is non-electrically connected to the hole-generating layer located in the third color light-emitting region.

[0009] Optionally, the wavelength of light emitted by the first color-emitting region is shorter than the wavelength of light emitted by the second color-emitting region; and / or

[0010] The wavelength of light emitted by the second color emitting region is shorter than the wavelength of light emitted by the third color emitting region.

[0011] Optionally, the light-emitting device further includes:

[0012] A first hole transport layer is disposed between the hole injection layer and the first light-emitting layer;

[0013] The second hole transport layer is disposed between the hole generation layer and the second light emission layer.

[0014] Optionally, the thickness of the first hole transport layer is 100-130 nm, and the thickness of the second hole transport layer is 40-60 nm.

[0015] Optionally, the light-emitting device further includes:

[0016] A first electron blocking layer is disposed between the first light-emitting layer and the first hole transport layer;

[0017] The second electron blocking layer is disposed between the second light-emitting layer and the second hole transport layer;

[0018] The thickness of the first electron blocking layer located in the second color emitting region is greater than the thickness of the first electron blocking layer located in the first color emitting region, and the thickness of the second electron blocking layer located in the second color emitting region is greater than the thickness of the second electron blocking layer located in the first color emitting region.

[0019] Optionally, the light-emitting device includes a third color light-emitting region, and the thickness of the first electron blocking layer located in the third color light-emitting region is greater than the thickness of the first electron blocking layer located in the second color light-emitting region.

[0020] The thickness of the second electron blocking layer located in the third color emitting region is greater than the thickness of the second electron blocking layer located in the second color emitting region.

[0021] Optionally, both the first light-emitting layer and the second light-emitting layer include a first color light-emitting layer, and the first color light-emitting layer is disposed in the first color light-emitting area;

[0022] Both the first light-emitting layer and the second light-emitting layer include a second color light-emitting layer, which is disposed in the second color light-emitting area, and the thickness of the first color light-emitting layer is less than the thickness of the second color light-emitting layer.

[0023] Optionally, the light-emitting device includes a third color light-emitting region, and both the first light-emitting layer and the second light-emitting layer include a third color light-emitting layer. The third color light-emitting layer is disposed in the third color light-emitting region, and the thickness of the second color light-emitting layer is less than the thickness of the third color light-emitting layer.

[0024] Secondly, embodiments of the present invention provide a display panel, including:

[0025] The light-emitting device described in the above embodiments.

[0026] Thirdly, embodiments of the present invention provide a display device, including:

[0027] The display panel described in the above embodiments.

[0028] The light-emitting device of this invention includes: a hole injection layer, a first light-emitting layer, an electron-generating layer, a hole-generating layer, a second light-emitting layer, and an electron injection layer stacked together. The light-emitting device includes a first color light-emitting region and a second color light-emitting region, and the hole-generating layer located in the first color light-emitting region and the hole-generating layer located in the second color light-emitting region are non-electrically connected. In the light-emitting device of this invention, the non-electrical connection between the hole-generating layer located in the first color light-emitting region and the hole-generating layer located in the second color light-emitting region prevents electrical conduction between them, thus preventing current crosstalk between them. This prevents lateral leakage current problems in the OLED stacked device structure, significantly improving the display crosstalk problem caused by lateral leakage current in low grayscale displays, improving display effect, and resulting in high luminous efficiency and long lifespan, meeting performance requirements. Attached Figure Description

[0029] Figure 1 This is a schematic diagram illustrating the arrangement of the color-emitting layer in the first light-emitting layer in an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram illustrating the configuration of the hole generation layer in an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of a light-emitting device in an embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of another configuration of the hole generation layer in an embodiment of the present invention;

[0033] Figure 5 This is another schematic diagram of the light-emitting device in an embodiment of the present invention;

[0034] Figure 6 This is another schematic diagram of the light-emitting device in an embodiment of the present invention.

[0035] Figure Labels

[0036] Hole injection layer 10;

[0037] First hole transport layer 11; Second hole transport layer 12;

[0038] First light-emitting layer 20;

[0039] Electron generation layer 30;

[0040] First electron transport layer 31; Second electron transport layer 32;

[0041] Hole generation layer 40;

[0042] Second light-emitting layer 50;

[0043] Electron injection layer 60;

[0044] First electron blocking layer 61; Second electron blocking layer 62;

[0045] First hole-blocking layer 63; Second hole-blocking layer 64;

[0046] First color emitting layer 21; Second color emitting layer 22; Third color emitting layer 23;

[0047] Cathode 71; Anode 72; Reflective layer 73; Light extraction layer 74;

[0048] Pixel definition layer 75; driving circuit 76; substrate 77. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] The terms "first," "second," etc., used in the specification and claims of this invention are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention can be implemented in orders other than those illustrated or described herein. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0051] like Figures 1 to 6 As shown, the light-emitting device of this embodiment includes:

[0052] The device comprises a hole injection layer 10, a first light-emitting layer 20, an electron generation layer 30, a hole generation layer 40, a second light-emitting layer 50, and an electron injection layer 60, which are stacked together. Electrons generated by the electron generation layer 30 and holes generated by the hole generation layer 40 enable the first light-emitting layer 20 and the second light-emitting layer 50 to emit light.

[0053] The light-emitting device may include a first color light-emitting region and a second color light-emitting region. The hole-generating layers located in the first color light-emitting region and the second color light-emitting region are not electrically connected. The hole-generating layers in the first and second color light-emitting regions may be spaced apart, such that they cannot be electrically connected. The first color light-emitting region may emit blue light, and the second color light-emitting region may emit red or green light.

[0054] A light-emitting device may include a first color light-emitting region, a second color light-emitting region, and a third color light-emitting region. For example, the first color light-emitting region may emit blue light, the second color light-emitting region may emit green light, and the third color light-emitting region may emit red light. Figure 3 As shown, the hole generation layer located in the first color light-emitting region and the hole generation layer located in the second color light-emitting region are non-electrically connected, and the hole generation layers in the first color light-emitting region and the second color light-emitting region can be spaced apart. The hole generation layer located in the third color light-emitting region is non-electrically connected to the hole generation layer in the second color light-emitting region, and the hole generation layer in the third color light-emitting region and the hole generation layer in the second color light-emitting region can be spaced apart. The electron generation layers 30 located in the first color light-emitting region, the second color light-emitting region, and the third color light-emitting region can be connected as a single unit, simplifying the manufacturing process.

[0055] like Figure 4 and Figure 5 As shown, the hole generation layer located in the first color light-emitting region and the hole generation layer located in the second color light-emitting region are non-electrically connected, and the hole generation layers in the first color light-emitting region and the hole generation layers in the second color light-emitting region can be spaced apart. The hole generation layer located in the third color light-emitting region is connected to the hole generation layer located in the second color light-emitting region. The electron generation layers 30 located in the first color light-emitting region, the second color light-emitting region, and the third color light-emitting region can be connected to one unit, simplifying the manufacturing process.

[0056] like Figure 6As shown, the hole generation layer located in the first color light-emitting region and the hole generation layer located in the second color light-emitting region are non-electrically connected, and the hole generation layers in the first color light-emitting region and the second color light-emitting region can be spaced apart. The hole generation layer located in the third color light-emitting region is integrally connected with the hole generation layer located in the second color light-emitting region, simplifying the manufacturing process. The electron generation layer located in the first color light-emitting region and the electron generation layer located in the second color light-emitting region are non-electrically connected, and the electron generation layers in the first color light-emitting region and the second color light-emitting region can be spaced apart. The electron generation layer located in the third color light-emitting region is integrally connected with the electron generation layer located in the second color light-emitting region, simplifying the manufacturing process.

[0057] In the light-emitting device of the present invention, the hole-generating layer located in the first color light-emitting region and the hole-generating layer located in the second color light-emitting region are non-electrically connected, so that the hole-generating layer located in the first color light-emitting region and the hole-generating layer located in the second color light-emitting region are not electrically conductive, preventing current crosstalk between the hole-generating layer located in the first color light-emitting region and the hole-generating layer located in the second color light-emitting region, preventing the lateral leakage current problem in the OLED stacked device structure, which can significantly improve the display crosstalk problem caused by lateral leakage current when the light-emitting device is displayed at low grayscale, improve the display effect, and the light-emitting device has high luminous efficiency, long service life, and can meet performance requirements.

[0058] In some embodiments, the electron generating layer 30 located in the first color light-emitting region and the electron generating layer 30 located in the second color light-emitting region can be non-electrically connected, and the electron generating layer 30 located in the first color light-emitting region and the electron generating layer 30 located in the second color light-emitting region can be spaced apart, so that the electron generating layer 30 located in the first color light-emitting region and the electron generating layer 30 located in the second color light-emitting region can be non-electrically connected, avoiding current crosstalk between the electron generating layer 30 located in the first color light-emitting region and the electron generating layer 30 located in the second color light-emitting region, preventing lateral leakage, and avoiding display crosstalk caused by lateral leakage current.

[0059] In some embodiments of the present invention, the light-emitting device may include a third color light-emitting region. The hole-generating layers located in the second and third color light-emitting regions may be non-electrically connected, and may be spaced apart. The first color light-emitting region may emit blue light, the second color light-emitting region may emit green light, and the third color light-emitting region may emit red light. This ensures that the hole-generating layers in the second and third color light-emitting regions are non-electrically connected, preventing current crosstalk between them, preventing lateral leakage, and avoiding display crosstalk caused by lateral leakage current.

[0060] In some embodiments, the wavelength of light emitted by the first color emitting region is shorter than the wavelength of light emitted by the second color emitting region. For example, the first color emitting region may emit blue light, and the second color emitting region may emit red or green light.

[0061] Optionally, the wavelength of light emitted by the second color emitting region is shorter than the wavelength of light emitted by the third color emitting region. For example, the first color emitting region can emit blue light, the second color emitting region can emit green light, and the third color emitting region can emit red light.

[0062] In embodiments of the present invention, the light-emitting device may further include:

[0063] The first hole transport layer 11 and the second hole transport layer 12 are disposed between the hole injection layer 10 and the first light-emitting layer 20, and the second hole transport layer 12 is disposed between the hole generation layer 40 and the second light-emitting layer 50.

[0064] Optionally, the thickness of the first hole transport layer 11 can be 100-130 nm, and the thickness of the second hole transport layer 12 can be 40-60 nm. For example, the thickness of the first hole transport layer 11 can be 105 nm, and the thickness of the second hole transport layer 12 can be 40 nm; the thickness of the first hole transport layer 11 can be 120 nm, and the thickness of the second hole transport layer 12 can be 50 nm. The specific thickness can be selected according to actual needs. A first hole transport layer thickness greater than 80 nm is beneficial for reducing light loss at the anode reflective metal and improving device efficiency.

[0065] In some embodiments, the light-emitting device may further include:

[0066] A first electron blocking layer 61 and a second electron blocking layer 62 are disposed between the first light-emitting layer 20 and the first hole transport layer 11, respectively. The first electron blocking layer 61 is disposed between the second light-emitting layer 50 and the second hole transport layer 12. The thickness of the first electron blocking layer located in the second color light-emitting region is greater than that located in the first color light-emitting region, and the thickness of the second electron blocking layer located in the second color light-emitting region is greater than that located in the first color light-emitting region. The first color light-emitting region can emit blue light, the second color light-emitting region can emit green light, and the third color light-emitting region can emit red light. This thickness setting can satisfy the requirements of a red / green / blue optical microcavity structure, which is beneficial to improving light emission efficiency.

[0067] In embodiments of the present invention, the light-emitting device may further include:

[0068] The first electron transport layer 31 and the second electron transport layer 32 are disposed between the electron generation layer 30 and the first light-emitting layer 20, and the second electron transport layer 32 is disposed between the electron injection layer 60 and the second light-emitting layer 50.

[0069] In embodiments of the present invention, the light-emitting device may further include:

[0070] The first hole blocking layer 63 and the second hole blocking layer 64 are disposed between the first light-emitting layer 20 and the first electron transport layer 31, and the second hole blocking layer 64 is disposed between the second light-emitting layer 50 and the second electron transport layer 32.

[0071] Optionally, the light-emitting device may include a third color light-emitting region, wherein the thickness of the first electron blocking layer 61 located in the third color light-emitting region is greater than the thickness of the first electron blocking layer 61 located in the second color light-emitting region; and the thickness of the second electron blocking layer 62 located in the third color light-emitting region is greater than the thickness of the second electron blocking layer 62 located in the second color light-emitting region.

[0072] In an embodiment of the present invention, the first light-emitting layer 20 and the second light-emitting layer 50 may both include a first color light-emitting layer 21. The first color light-emitting layer 21 is disposed in the first color light-emitting region, and the projections of the first color light-emitting layer 21 in the first light-emitting layer 20 and the second light-emitting layer 50 onto the substrate may overlap.

[0073] Both the first light-emitting layer 20 and the second light-emitting layer 50 may include a second color light-emitting layer 22, which is disposed in the second color light-emitting region. The thickness of the first color light-emitting layer 21 is less than the thickness of the second color light-emitting layer 22. The projections of the second color light-emitting layer 22 in the first light-emitting layer 20 and the second light-emitting layer 50 onto the substrate may coincide.

[0074] Optionally, the light-emitting device may include a third-color light-emitting region. Both the first light-emitting layer 20 and the second light-emitting layer 50 may include a third-color light-emitting layer 23, which is disposed within the third-color light-emitting region. The thickness of the second-color light-emitting layer 22 is less than the thickness of the third-color light-emitting layer 23. The projections of the third-color light-emitting layer 23 in the first light-emitting layer 20 and the second light-emitting layer 50 onto the substrate may overlap. The first-color light-emitting layer 21 can emit blue light, the second-color light-emitting layer 22 can emit green light, and the third-color light-emitting layer 23 can emit red light. The first-color light-emitting region can emit blue light, the second-color light-emitting region can emit green light, and the third-color light-emitting region can emit red light. Increasing the thickness of the red / green light-emitting layer helps improve the lifespan of the red / green light-emitting device and also provides optical microcavity compensation. Furthermore, because the red light-emitting device has a lower voltage, its light-emitting layer can be thicker than that of the green light-emitting device.

[0075] Example 1

[0076] Based on the above test results, the preferred device structure is to pattern the film layer that generates the lateral leakage current, thereby reducing the generation of lateral leakage current. The test results show that the lateral leakage current of the hole generation layer is significantly higher than that of the electron generation layer. Therefore, the preferred device structure is to pattern the hole generation layer. The device fabrication process is as follows:

[0077] 1. A driving circuit 76, a reflective layer 73, an anode 72, and a pixel definition layer 75 are fabricated on a glass substrate 77 to illuminate the pixel area of ​​an organic electroluminescent device;

[0078] 2. A hole injection layer 10 and a first hole transport layer 11 are covered on the entire surface of a glass substrate. The thickness of the first hole transport layer is >80 nm, and the thickness of the first hole transport layer 11 is greater than the thickness of the second hole transport layer 12 described below. The hole injection layer 10 can be a p-type dopant of a strong electron-withdrawing system and a dopant of the hole transport material, such as hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinone dimethyl ether (F4TCNQ), 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane, etc. Hole transport materials are preferably aromatic amines and dimethylfluorene or carbazole materials with hole transport properties, such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluorene-2-yl)-N-phenylamino]biphenyl (DFLDPBi), 4,4'-bis(9-carbazolyl)biphenyl (CBP), 9-phenyl-3-[4-(10-phenyl-9-anthrayl)phenyl]-9H-carbazole (PCzPA), etc.

[0079] 3. After step 2 is completed, the first electron blocking layer 61 is deposited by vapor deposition. The materials of the first electron blocking layer 61 and the second electron blocking layer 62 can preferably be materials with better hole transport properties, such as 2-(4-tert-butylphenyl)-5-(4-biphenyl)1,3,4-diazole, 3(biphenyl)-4-yl-5(4-tert-butylphenyl)-4H-1,2,4-triazole, etc. The first electron blocking layer located in the first color emitting region and the first electron blocking layer located in the second color emitting region can have the following characteristics: ① The first electron blocking layers in the two regions do not overlap or the overlapping area is limited to the area above the pixel definition layer; ② The thickness of the first electron blocking layer located in the second color emitting region is greater than the thickness of the first electron blocking layer located in the first color emitting region, and the thickness of the first electron blocking layer located in the third color emitting region is greater than the thickness of the first electron blocking layer located in the second color emitting region and the thickness of the first electron blocking layer located in the first color emitting region.

[0080] 4. After step 3 is completed, the first light-emitting layer 20 is vapor-deposited. The first light-emitting layer 20 includes a first color light-emitting layer 21, a second color light-emitting layer 22, and a third color light-emitting layer 23. The first color light-emitting layer 21 is disposed in the first color light-emitting area, the second color light-emitting layer 22 is disposed in the second color light-emitting area, and the third color light-emitting layer 23 is disposed in the third color light-emitting area. The first color light-emitting layer 21 disposed in the first color light-emitting area can emit blue, the second color light-emitting layer 22 disposed in the second color light-emitting area can emit green, and the third color light-emitting layer 23 disposed in the third color light-emitting area can emit red. It has the following characteristics: ① The first color light-emitting layer 21, the second color light-emitting layer 22, and the third color light-emitting layer 23 do not overlap or the overlapping area is limited to the area above the pixel definition layer; ② The thickness of the second color light-emitting layer 22 disposed in the second color light-emitting area is greater than the thickness of the first color light-emitting layer 21 disposed in the first color light-emitting area, and the thickness of the third color light-emitting layer 23 disposed in the third color light-emitting area is greater than the thickness of the second color light-emitting layer 22 disposed in the second color light-emitting area. The structure of the light-emitting device can be as follows: Figure 1 As shown;

[0081] The light-emitting layer may contain one material or a mixture of two or more materials. The light-emitting material in the light-emitting layer may be a blue light-emitting material, a green light-emitting material, or a red light-emitting material. Blue luminescent materials can be selected from pyrene derivatives, anthracene derivatives, fluorene derivatives, perylene derivatives, styrylamine derivatives, metal complexes, etc., such as N1,N6-bis([1,1'-biphenyl]-2-yl)-N1,N6-bis([1,1'-biphenyl]-4-yl)pyrene-1,6-diamine, 9,10-bis-(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis-2-naphthylanthracene (MADN), 2,5,8,11-tetra-tert-butylperylene (TBPe), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (BDAV Bi), 4,4'-bis[4-(di-p-tolylamino)styryl]biphenyl (DPAVBi), and bis(4,6-difluorophenylpyridine-C2,N)pyridinecarboxyiridium (FIrpic). Green luminescent materials can be selected from sources such as coumarin dyes, quinacridine copper derivatives, polycyclic aromatic hydrocarbons, diamine anthracene derivatives, carbazole derivatives, and metal complexes. Examples include coumarin 6 (C-6), coumarin 545T (C-525T), quinacridine copper (QA), N,N'-dimethylquinacridone (DMQA), 5,12-diphenylnaphthonaphthalene (DPT), N10,N10'-diphenyl-N10,N10'-dibenzoyl-9,9'-dianthracene-10,10'-diamine (BA-NPB), tris(8-hydroxyquinoline)aluminum(III) (Alq3), tris(2-phenylpyridine)iridium (Ir(ppy)3), and di(2-phenylpyridine)iridium acetylacetonate (...). Ir(ppy)2(acac)), red luminescent materials are selected from materials such as the DCM series and metal complexes, specifically: 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulonidin-9-enyl)-4H-pyran (DCJTB), bis(1-phenylisoquinoline)(acetylacetone)iridium(III)(Ir(piq)2(acac)), octaethylporphyrin platinum (abbreviated as: PtOEP), bis(2-(2'-benzothiophene)pyridine-N,C3')(acetylacetone)iridium (abbreviated as: Ir(btp)2(acac), etc.

[0082] 5. After step 4 is completed, the first hole-blocking layer 63, the first electron transport layer 31, the electron generating layer 30, and the hole generating layer 40 are deposited on the entire surface by vapor deposition. The first hole-blocking layer 63 and the first electron transport layer 31 can preferably be aromatic heterocyclic compounds, such as imidazole derivatives, imidazopyridine derivatives, benzimidazole-phenanthridine derivatives, etc.; pyrimidine derivatives, triazine derivatives, etc.; quinoline derivatives, isoquinoline derivatives, phenanthreneline derivatives, etc., compounds containing a nitrogen-containing six-membered ring structure (including compounds with phosphine oxide substituents on the heterocycle), for example, 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD). Examples of suitable materials include 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenyl)-1,2,4-triazole (TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenyl)-1,2,4-triazole (p-EtTAZ), phenanthroline (BPhen), (BCP), and 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (BzOs). The electron generation layer 30 can be composed of small molecule materials such as aromatic heterocyclic compounds and quinoline derivatives, combined with metal Yb or Li, wherein the metal doping ratio ranges from 1% to 20%. The hole generation layer 40 and the hole injection layer 10 can be made of the same material.

[0083] 6. After step 5 is completed, a patterned hole-generating layer 40 is prepared, which can be as follows: Figure 2 As shown, this device structure design can significantly improve the lateral leakage current between two adjacent pixels;

[0084] 7. The second hole transport layer 12, the second electron blocking layer 62, the second light-emitting layer 50, the second hole blocking layer 64, the second electron transport layer 32, the electron injection layer 60, the cathode 71, and the light extraction layer 74 are fabricated sequentially. The structure of the light-emitting device can be as follows: Figure 3 As shown. The thickness of the second hole transport layer 12 is <60nm, and the material of the second hole transport layer 12 can be the same as that of the first hole transport layer 11. The second light-emitting layer 50, the second hole blocking layer 64, and the second electron transport layer 32 are all the same in material and thickness as the corresponding first light-emitting layer 20, first hole blocking layer 63, and first electron transport layer 31, respectively, and the thickness of the second electron blocking layer 62 is ≤ the thickness of the first electron blocking layer 61.

[0085] The electron injection layer 60 can preferably be an alkali metal or a metal, such as LiF, Yb, Mg, Ca or their compounds.

[0086] Below are some common specific materials.

[0087]

[0088] Among them, F4TCNQ can be used as a hole injection material, m-MTDATA can be used as a hole injection layer dopant, NPB is generally used as a hole transport layer material or a light extraction layer material, TPBi is usually used as a hole blocking layer material, BCP is usually used as an electron charge generation layer, CBP is usually used as a red and green light host material, and Ir(ppy)3 and Ir(piq)(acac) can be used as green and red light dopants, respectively.

[0089] The cathode layer can be one of the following metal materials: Mg, Ag, Al, Li, K, Ca, etc., or an alloy of the above metal materials: MgxAg(1-x), LixAl(1-x), LixCa(1-x), LixAg(1-x), etc. The cathode thickness ranges from 10 to 20 nm.

[0090] The light extraction layer can preferably be an organic small molecule material with a refractive index n > 1.9 @ 550 nm to improve the light extraction efficiency of the device.

[0091] Example 2

[0092] Considering that hole generation layers 40 need to be formed separately in Example 1, which is quite complex, and considering that the actual lateral leakage current mainly occurs between the blue light-emitting device structure and the green or red light-emitting device structure, the device structure of Example 1 can be simplified to reduce the difficulty of device fabrication.

[0093] 1. A driving circuit 76, a reflective layer 73, an anode 72, and a pixel definition layer 75 are fabricated on a glass substrate 77 to illuminate the pixel area of ​​an organic electroluminescent device;

[0094] 2. A hole injection layer 10 and a first hole transport layer 11 are covered on the entire surface of a glass substrate. The thickness of the first hole transport layer 11 is >80 nm, and the thickness of the first hole transport layer 11 is greater than the thickness of the second hole transport layer 12 described below. The hole injection layer 10 can be a p-type dopant of a strong electron-withdrawing system and a dopant of a hole transport material, such as hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinone dimethyl ether (F4TCNQ), 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane, etc. Hole transport materials can preferably be aromatic amines, dimethylfluorene, or carbazole materials with hole transport properties, such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluorene-2-yl)-N-phenylamino]biphenyl (DFLDPBi), 4,4'-bis(9-carbazolyl)biphenyl (CBP), and 9-phenyl-3-[4-(10-phenyl-9-anthrayl)phenyl]-9H-carbazole (PCzPA), etc.

[0095] 3. After step 2 is completed, the first electron blocking layer 61 is deposited by vapor deposition. The materials of the first electron blocking layer 61 and the second electron blocking layer 62 can preferably be materials with better hole transport properties, such as 2-(4-tert-butylphenyl)-5-(4-biphenyl)1,3,4-diazole, 3(biphenyl)-4-yl-5-(4-tert-butylphenyl)-4H-1,2,4-triazole, etc. The first electron blocking layer located in the first color emitting region and the first electron blocking layer located in the second color emitting region can have the following characteristics: ① The first electron blocking layers 61 in the two regions do not overlap or the overlapping area is limited to the area above the pixel definition layer; ② The thickness of the first electron blocking layer 61 located in the second color emitting region is greater than the thickness of the first electron blocking layer 61 located in the first color emitting region, and the thickness of the first electron blocking layer 61 located in the third color emitting region is greater than the thickness of the first electron blocking layer 61 located in the second color emitting region and the thickness of the first electron blocking layer 61 located in the first color emitting region.

[0096] 4. After step 3 is completed, the first light-emitting layer 20 is vapor-deposited. The first light-emitting layer 20 includes a first color light-emitting layer 21, a second color light-emitting layer 22, and a third color light-emitting layer 23. The first color light-emitting layer 21 is disposed in the first color light-emitting area, the second color light-emitting layer 22 is disposed in the second color light-emitting area, and the third color light-emitting layer 23 is disposed in the third color light-emitting area. The first color light-emitting layer 21 disposed in the first color light-emitting area can emit blue, the second color light-emitting layer 22 disposed in the second color light-emitting area can emit green, and the third color light-emitting layer 23 disposed in the third color light-emitting area can emit red. It has the following characteristics: ① The first color light-emitting layer 21, the second color light-emitting layer 22, and the third color light-emitting layer 23 do not overlap or the overlapping area is limited to the area above the pixel definition layer; ② The thickness of the second color light-emitting layer 22 disposed in the second color light-emitting area is greater than the thickness of the first color light-emitting layer 21 disposed in the first color light-emitting area, and the thickness of the third color light-emitting layer 23 disposed in the third color light-emitting area is greater than the thickness of the second color light-emitting layer 22 disposed in the second color light-emitting area. The structure of the light-emitting device can be as follows: Figure 4 As shown.

[0097] The light-emitting layer can contain one material or a mixture of two or more materials. The light-emitting layer can be a blue light-emitting material, a green light-emitting material, or a red light-emitting material. Blue luminescent materials can be selected from pyrene derivatives, anthracene derivatives, fluorene derivatives, perylene derivatives, styrylamine derivatives, metal complexes, etc., such as N1,N6-bis([1,1'-biphenyl]-2-yl)-N1,N6-bis([1,1'-biphenyl]-4-yl)pyrene-1,6-diamine, 9,10-bis-(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis-2-naphthylanthracene (MADN), 2,5,8,11-tetra-tert-butylperylene (TBPe), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (BDAV Bi), 4,4'-bis[4-(di-p-tolylamino)styryl]biphenyl (DPAVBi), and bis(4,6-difluorophenylpyridine-C2,N)pyridinecarboxyiridium (FIrpic). Green luminescent materials can be selected from sources such as coumarin dyes, quinacridine copper derivatives, polycyclic aromatic hydrocarbons, diamine anthracene derivatives, carbazole derivatives, and metal complexes. Examples include coumarin 6 (C-6), coumarin 545T (C-525T), quinacridine copper (QA), N,N'-dimethylquinacridone (DMQA), 5,12-diphenylnaphthonaphthalene (DPT), N10,N10'-diphenyl-N10,N10'-dibenzoyl-9,9'-dianthracene-10,10'-diamine (BA-NPB), tris(8-hydroxyquinoline)aluminum(III) (Alq3), tris(2-phenylpyridine)iridium(Ir(ppy)3), and di(2-phenylpyridine)iridium(I) acetylacetonate (I). The red luminescent material is selected from materials such as the DCM series and metal complexes, specifically 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulonidin-9-enyl)-4H-pyran (DCJTB), bis(1-phenylisoquinoline)(acetylacetone)iridium(III))(Ir(piq)2(acac)), octaethylporphyrin platinum (abbreviated as: PtOEP), bis(2-(2'-benzothiophene)pyridine-N,C3')(acetylacetone)iridium (abbreviated as: Ir(btp)2(acac), etc.

[0098] 5. After step 4 is completed, the first hole-blocking layer 63, the first electron transport layer 31, the electron generating layer 30, and the hole generating layer 40 are deposited on the entire surface by vapor deposition. The first hole-blocking layer 63 and the first electron transport layer 31 can preferably be aromatic heterocyclic compounds, such as imidazole derivatives, imidazopyridine derivatives, benzimidazole-phenanthridine derivatives, etc.; pyrimidine derivatives, triazine derivatives, etc.; quinoline derivatives, isoquinoline derivatives, phenanthreneline derivatives, etc., compounds containing a nitrogen-containing six-membered ring structure (including compounds with phosphine oxide substituents on the heterocycle), such as 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD). Examples of suitable materials include 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenyl)-1,2,4-triazole (TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenyl)-1,2,4-triazole (p-EtTAZ), phenanthroline (BPhen), (BCP), and 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (BzOs). The electron generation layer 30 can be composed of small molecule materials such as aromatic heterocyclic compounds and quinoline derivatives, combined with metal Yb or Li, wherein the metal doping ratio ranges from 1% to 20%. The hole generation layer 40 and the hole injection layer 10 can be made of the same material.

[0099] 6. After step 5 is completed, a patterned hole-generating layer 40 is prepared, which can be as follows: Figure 5 As shown, this device structure design can significantly improve the lateral leakage current between blue and red / green light-emitting devices;

[0100] 7. The second hole transport layer 12, the second electron blocking layer 62, the second light-emitting layer 50, the second hole blocking layer 64, the second charge transport layer 32, the electron injection layer 60, the cathode 71, and the light extraction layer 74 are fabricated sequentially. The structure of the light-emitting device can be as follows: Figure 5 As shown. The thickness of the second hole transport layer 12 is <60nm, and the material of the second hole transport layer 12 can be the same as that of the first hole transport layer 11. The second light-emitting layer 50, the second hole blocking layer 64, and the second electron transport layer 32 are all the same in material and thickness as the corresponding first light-emitting layer 20, first hole blocking layer 63, and first electron transport layer 31, respectively, and the thickness of the second electron blocking layer 62 is ≤ the thickness of the first electron blocking layer 61.

[0101] Example 3

[0102] Considering that both the hole generation layer and the electron generation layer generate lateral leakage current, and that these two layers are adjacent in the device structure, the fabrication process can simultaneously pattern the hole generation layer and the electron generation layer, minimizing the lateral leakage current of the display device. The device structure can be as follows: Figure 6 As shown.

[0103] In this invention, all device descriptions refer to dual-layer light-emitting devices, but the corresponding thickness rules also apply to triple-layer and higher layer light-emitting devices. The preferred blue, green, and red device structures and thicknesses in this invention are shown below.

[0104] The device structure located in the first color emitting region, which can emit blue light, has the following preferred blue device structure and thickness:

[0105] Anode 72 (5-15nm) / Hole injection layer 10 (7-12nm) / First hole transport layer 11 (100-130nm) / First electron blocking layer 61 (5-15nm) / First color emitting layer 21 (10-30nm) / First hole blocking layer 63 (5-15nm) / First electron transport layer 31 (15-25nm) / Electron generating layer 30 (15-25nm) / Hole generating layer 40 (7-12nm) / Second hole transport layer 12 (40-60nm) / Second electron blocking layer 62 (5-15nm) / First color emitting layer 21 (10-30nm) / Second hole blocking layer 64 (5-10nm) / Second electron transport layer 32 (30-40nm) / Electron injection layer 60 (1-2nm) / Cathode 71 (10-14nm) / Light extraction layer 74 (60-90nm).

[0106] The device structure located in the second color emitting region, which can emit green light, preferably has the following characteristics and thickness:

[0107] Anode 72 (5-15nm) / Hole injection layer 10 (7-12nm) / First hole transport layer 11 (100-130nm) / First electron blocking layer 61 (25-35nm) / Second color emitting layer 22 (30-40nm) / First hole blocking layer 63 (5-15nm) / First electron transport layer 31 (15-25nm) / Electron generation layer 30 (15-25nm) / Hole generation layer 40 (7-12nm) / Second hole transport layer 12 (40-60nm) / Second electron blocking layer 62 (15-30nm) / Second color emitting layer 22 (30-40nm) / Second hole blocking layer 64 (5-10nm) / Second electron transport layer 32 (30-40nm) / Electron injection layer 60 (1-2nm) / Cathode 71 (10-14nm) / Light extraction layer 74 (60-90nm).

[0108] The device structure located in the third color emitting region, which can emit red light, preferably has the following characteristics and thickness:

[0109] Anode 72 (5-15nm) / Hole injection layer 10 (7-12nm) / First hole transport layer 11 (100-130nm) / First electron blocking layer 61 (40-60nm) / Third color emitting layer 23 (40-60nm) / First hole blocking layer 63 (5-15nm) / First electron transport layer 31 (15-25nm) / Electron generation layer 30 (15-25nm) / Hole generation layer 40 (7-12nm) / Second hole transport layer 12 (40-60nm) / Second electron blocking layer 62 (20-40nm) / Third color emitting layer 23 (40-60nm) / Second hole blocking layer 64 (5-10nm) / Second electron transport layer 32 (30-40nm) / Electron injection layer 60 (1-2nm) / Cathode 71 (10-14nm) / Light extraction layer 74 (60-90nm).

[0110] Increasing the thickness of the first hole transport layer 11 leads to a significant increase in the lateral leakage current of the device. This lateral leakage current issue is eliminated by patterning the electron generation layer 30 and hole generation layer 40 of the blue, green, and red light-emitting device structures. A first hole transport layer thickness greater than 80 nm can easily cause a substantial increase in leakage current in the display device structure, resulting in the second color light-emitting region emitting light simultaneously when the first color light-emitting region emits light, causing lateral crosstalk. The solution in this invention can prevent lateral leakage current in the display device structure.

[0111] The display panel of this invention includes:

[0112] The light-emitting device described in the above embodiments. A display panel equipped with the light-emitting device described in the above embodiments is less prone to display crosstalk and has a better display effect.

[0113] The display device of this invention includes:

[0114] The display panel described in the above embodiments. Display devices equipped with the display panel described in the above embodiments are less prone to display crosstalk and have good display performance.

[0115] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. A light-emitting device, characterized in that, include: The stacked layers are a hole injection layer, a first light-emitting layer, an electron generation layer, a hole generation layer, a second light-emitting layer, and an electron injection layer. The light-emitting device includes a first color light-emitting region and a second color light-emitting region, and the hole-generating layer located in the first color light-emitting region and the hole-generating layer located in the second color light-emitting region are non-electrically connected.

2. The light-emitting device according to claim 1, characterized in that, The electron generating layer located in the first color emitting region is non-electrically connected to the electron generating layer located in the second color emitting region.

3. The light-emitting device according to claim 1, characterized in that, The light-emitting device includes a third color light-emitting region, and the hole-generating layer located in the second color light-emitting region is non-electrically connected to the hole-generating layer located in the third color light-emitting region.

4. The light-emitting device according to claim 3, characterized in that, The wavelength of light emitted by the first color emitting region is shorter than the wavelength of light emitted by the second color emitting region; and / or The wavelength of light emitted by the second color emitting region is shorter than the wavelength of light emitted by the third color emitting region.

5. The light-emitting device according to claim 1, characterized in that, Also includes: A first hole transport layer is disposed between the hole injection layer and the first light-emitting layer; The second hole transport layer is disposed between the hole generation layer and the second light emission layer.

6. The light-emitting device according to claim 5, characterized in that, The thickness of the first hole transport layer is 100-130 nm, and the thickness of the second hole transport layer is 40-60 nm.

7. The light-emitting device according to claim 5, characterized in that, Also includes: A first electron blocking layer is disposed between the first light-emitting layer and the first hole transport layer; The second electron blocking layer is disposed between the second light-emitting layer and the second hole transport layer; The thickness of the first electron blocking layer located in the second color emitting region is greater than the thickness of the first electron blocking layer located in the first color emitting region, and the thickness of the second electron blocking layer located in the second color emitting region is greater than the thickness of the second electron blocking layer located in the first color emitting region.

8. The light-emitting device according to claim 7, characterized in that, The light-emitting device includes a third color light-emitting region, and the thickness of the first electron blocking layer located in the third color light-emitting region is greater than the thickness of the first electron blocking layer located in the second color light-emitting region. The thickness of the second electron blocking layer located in the third color emitting region is greater than the thickness of the second electron blocking layer located in the second color emitting region.

9. The light-emitting device according to claim 1, characterized in that, Both the first light-emitting layer and the second light-emitting layer include a first color light-emitting layer, and the first color light-emitting layer is disposed in the first color light-emitting area; Both the first light-emitting layer and the second light-emitting layer include a second color light-emitting layer, which is disposed in the second color light-emitting area, and the thickness of the first color light-emitting layer is less than the thickness of the second color light-emitting layer.

10. The light-emitting device according to claim 9, characterized in that, The light-emitting device includes a third color light-emitting region. Both the first light-emitting layer and the second light-emitting layer include a third color light-emitting layer. The third color light-emitting layer is disposed in the third color light-emitting region. The thickness of the second color light-emitting layer is less than the thickness of the third color light-emitting layer.

11. A display panel, characterized in that, include: The light-emitting device according to any one of claims 1-10.

12. A display device, characterized in that, include: The display panel as described in claim 11.

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