Laminated device and display device

Abstract

The invention discloses a laminated device and a display device, the laminated device comprises an electron blocking common layer, compared with a non-common electron blocking functional layer, the structure of the laminated device is simplified, an auxiliary doping material is added in a light emitting unit, and the light emitting efficiency is improved. The energy level of the auxiliary doping material is between the energy level of the main body material and the energy level of the main doping material, so that when the main body material, the main doping material and the auxiliary doping material in the light-emitting unit transfer energy, the energy is preferentially transferred to the auxiliary doping material from the main body material and then transferred to the main doping material from the auxiliary doping material; therefore, the energy transfer is easier, the energy loss in the energy transfer process is reduced, the damage to the material in the light-emitting unit is reduced, and the service life of the laminated device is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of light sources, and in particular to a stacked device and a display apparatus. Background Art

[0002] In recent years, OLED displays have developed rapidly around the world. With the continuous improvement of OLED display technology, the application field of OLED displays has gradually expanded to medium and large-sized displays. In the field of medium and large-sized displays, higher performance requirements are placed on the displays, especially in terms of life and power consumption. In this context, the application demand for long-life and high-efficiency stacked OLED devices is also increasing. At present, stacked OLED devices are usually simplified to varying degrees, but the simplified stacked OLED devices may have problems that affect their lifespan. Therefore, it is urgent to study stacked devices that simplify the structure while improving their lifespan. Summary of the invention

[0003] In view of this, the present application provides a stacked device and a display apparatus, aiming to improve the problem that the existing stacked devices cannot balance the simplified structure and long life performance.

[0004] In a first aspect, an embodiment of the present application provides a stacked device, comprising:

[0005] A first electrode is disposed on one side of the substrate;

[0006] A plurality of light-emitting units are arranged on a side of the first electrode facing away from the substrate;

[0007] A charge generation layer is disposed between adjacent light-emitting units;

[0008] A second electrode is disposed on a side of the charge generation layer away from the first electrode;

[0009] Wherein, an electron blocking common layer is provided between at least one of the light-emitting units and the first electrode, and the orthographic projection of the electron blocking common layer on the substrate at least covers the orthographic projection of the light-emitting unit on the substrate;

[0010] At least one of the light-emitting units includes a main material, a main doping material and an auxiliary doping material, and the energy level of the auxiliary doping material is between the energy level of the main material and the energy level of the main doping material.

[0011] Optionally, in some embodiments of the present application, the plurality of light-emitting units include at least a first light-emitting unit and a second light-emitting unit, the first light-emitting unit is disposed between the first electrode and the second light-emitting unit, and the electron blocking common layer is disposed between the first electrode and the first light-emitting unit.

[0012] Optionally, in some embodiments of the present application, the first light-emitting unit includes a first I light-emitting layer, a first II light-emitting layer, and a first III light-emitting layer having different light-emitting colors, and the orthographic projection of the electron blocking common layer on the substrate at least covers the orthographic projections of the first I light-emitting layer, the first II light-emitting layer, and the first III light-emitting layer on the substrate.

[0013] Optionally, in some embodiments of the present application, the second light-emitting unit includes a second I light-emitting layer, a second II light-emitting layer and a second III light-emitting layer, and a first electron blocking layer corresponding to the second I light-emitting layer, a second electron blocking layer corresponding to the second II light-emitting layer and a third electron blocking layer corresponding to the second III light-emitting layer are arranged between the second light-emitting unit and the charge generation layer; the electron blocking common layer and the third electron blocking layer are of the same layer and material.

[0014] Optionally, in some embodiments of the present application, the first electron blocking layer is set as a red electron blocking layer, the second electron blocking layer is set as a green electron blocking layer, and the third electron blocking layer and the electron blocking common layer are both set as blue electron blocking layers.

[0015] Optionally, in some embodiments of the present application, the thickness of the electron blocking common layer ranges from 5 nm to 8 nm.

[0016] Optionally, in some embodiments of the present application, the LOMO energy level of the main material is greater than the LOMO energy level of the auxiliary doping material, and the LOMO energy level of the auxiliary doping material is greater than the LOMO energy level of the main doping material.

[0017] Optionally, in some embodiments of the present application, the absolute value of the difference between the LOMO energy levels of the main material and the auxiliary doping material, and between the auxiliary doping material and the main doping material is greater than 0.1 eV.

[0018] Optionally, in some embodiments of the present application, the HOMO energy level of the main material is lower than the HOMO energy level of the auxiliary doping material, and the HOMO energy level of the auxiliary doping material is lower than the HOMO energy level of the main doping material.

[0019] Optionally, in some embodiments of the present application, the absolute value of the difference between the HOMO energy levels of the main material and the auxiliary doping material, and between the auxiliary doping material and the main doping material is greater than 0.1 eV.

[0020] Optionally, in some embodiments of the present application, the main doping material and the auxiliary doping material include at least one of platinum-platinum, platinum-iridium, iridium-platinum, iridium-iridium or osmium-osmium.

[0021] Optionally, in some embodiments of the present application, the main doping material includes at least the following molecular structure:

[0022]

[0023] Optionally, in some embodiments of the present application, the auxiliary doping material includes at least the following molecular structure:

[0024] Optionally, in some embodiments of the present application, the doping concentration of the main material in the light-emitting unit ranges from 80wt% to 99.8wt%, the doping concentration of the main doping material in the light-emitting unit ranges from 0.1wt% to 10wt%, and the doping concentration of the auxiliary doping material in the light-emitting unit ranges from 0.1wt% to 10wt%.

[0025] In a second aspect, an embodiment of the present application further provides a display device, comprising the aforementioned stacked device.

[0026] In the stacked device provided in the embodiment of the present application, an electron blocking common layer is provided, which simplifies the structure of the stacked device compared to the electron blocking functional layer that is not provided in common. At the same time, an auxiliary doping material is added in the light-emitting unit, and the energy level of the auxiliary doping material is between the energy level of the main material and the energy level of the main doping material. When the main material, the main doping material and the auxiliary doping material in the light-emitting unit are transferring energy, the energy is preferentially transferred from the main material to the auxiliary doping material, and then from the auxiliary doping material to the main doping material, so that the energy transfer is easier, and the energy loss is reduced during the energy transfer process, and the damage to the material itself in the light-emitting unit is reduced, thereby extending the life of the stacked device. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 It is a schematic diagram of the structure of a stacked device in the prior art;

[0029] Figure 2 It is a schematic diagram of the structure of a simplified stacked device of the present application.

[0030] Figure numerals: 10, first electrode; 20, light-emitting unit; 21, first light-emitting unit; 211, first I light-emitting layer; 212, first II light-emitting layer; 213, first III light-emitting layer; 22, second light-emitting unit; 221, second I light-emitting layer; 222, second II light-emitting layer; second III light-emitting layer; 30, charge generation layer; 40, second electrode; 50, electron blocking common layer; 60, electron blocking layer; 61, first electron blocking layer; 62, second electron blocking layer; 63, third electron blocking layer. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0033] In this application, unless otherwise stated, directional words such as "upper" and "lower" generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. In addition, in the description of this application, the term "including" means "including but not limited to". The terms first, second, third, etc. are used only as labels and do not impose numerical requirements or establish an order.

[0034] In this application, "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

[0035] In the present application, "at least one" means one or more, and "plurality" means two or more. "One or more", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple, respectively.

[0036] In the present application, when a layer is formed "on" another layer, the so-called "on" is a broad concept, which may indicate that the formed another layer is adjacent to the certain layer, or may indicate that there are other spacing structural layers between the another layer and the certain layer. For example, when a second electrode is formed "on" the first carrier functional layer, the so-called "on" may indicate that the formed second electrode is adjacent to the first carrier functional layer, or may indicate that there are other spacing structural layers between the second electrode and the first carrier functional layer, such as a light-emitting layer.

[0037] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0038] refer to Figure 1 , general stacked devices include:

[0039] A first electrode 10 is disposed on one side of the substrate;

[0040] A plurality of light-emitting units 20 are arranged on a side of the first electrode 10 facing away from the substrate;

[0041] The charge generation layer 30 is disposed between adjacent light emitting units 20;

[0042] The second electrode 40 is disposed on a side of the charge generation layer 30 away from the first electrode 10;

[0043] Among them, each light-emitting unit 20 includes a first I light-emitting layer 211, a first II light-emitting layer 212 and a first III light-emitting layer 213 with different light-emitting colors, and a first electron blocking layer 61, a second electron blocking layer 62 and a third electron blocking layer 63 corresponding to the first I light-emitting layer 211, the first II light-emitting layer 212, and the first III light-emitting layer 213 respectively.

[0044] With the development of stacked devices with simplified designs, the present application provides a stacked device and a display apparatus, which not only ensure the characteristics of simple structure and light weight, but also ensure the luminous efficiency and long life of the device.

[0045] According to a first aspect of an embodiment of the present application, a stacked device is provided, comprising:

[0046] A first electrode is disposed on one side of the substrate;

[0047] A plurality of light-emitting units are arranged on a side of the first electrode facing away from the substrate;

[0048] A charge generation layer is disposed between adjacent light-emitting units;

[0049] A second electrode is disposed on a side of the charge generation layer away from the first electrode;

[0050] Wherein, an electron blocking common layer is arranged between at least one light-emitting unit and the first electrode, and the orthographic projection of the electron blocking common layer on the substrate at least covers the orthographic projection of the light-emitting unit on the substrate;

[0051] At least one light-emitting unit includes a main material, a main doping material and an auxiliary doping material, wherein the energy level of the auxiliary doping material is between the energy level of the main material and the energy level of the main doping material.

[0052] It can be understood that the arrangement of a common electron blocking layer in the stacked device simplifies the structure of the stacked device compared to the non-common electron blocking functional layer; at the same time, an auxiliary doping material is added to the light-emitting unit, and the energy level of the auxiliary doping material is between the energy level of the main material and the energy level of the main doping material, so that when the main material, the main doping material and the auxiliary doping material in the light-emitting unit are transferring energy, the energy is preferentially transferred from the main material to the auxiliary doping material, and then from the auxiliary doping material to the main doping material, so that the energy transfer is easier and the energy loss is reduced during the energy transfer process, thereby realizing the preparation of a simplified stacked device with a long life.

[0053] It should be noted that the HOMO energy level of the electron blocking common layer ranges from 5.6 to 5.7 eV. The energy level of the electron blocking layer of general green pixels and red pixels ranges from 5.5 to 5.6 eV. Therefore, compared with the electron blocking layer of red pixels and green pixels, the energy level of the electron blocking common layer is deeper and has a stronger blocking effect on holes, resulting in insufficient holes in the light-emitting layer of red pixels and green pixels, affecting the service life.

[0054] It needs to be further explained that OLED light emission is generated by the energy transfer and radiation of excitons. The energy transfer of excitons is generally transferred from the main material to the main doping material. The T1 energy level of the main doping material is quite different from that of the main material, resulting in incomplete energy transfer. Auxiliary doping materials are added to the light-emitting unit, and the T1 energy level of the auxiliary doping materials is between the T1 energy level of the main material and the T1 energy level of the main doping material. Therefore, the T1 energy level of the auxiliary doping material is in the form of a "step" between the T1 energy level of the main material and the T1 energy level of the main doping material, making it easier and more sufficient for energy to transfer from the T energy level of the main material to the T1 energy level of the main doping material, thereby reducing energy loss during the energy transfer process and thus improving the service life of the stacked device.

[0055] It should be further explained that the auxiliary doping material is also beneficial to improve the dispersibility of the main doping material and the main material. When the auxiliary doping material is not introduced, the doping material in the light-emitting layer is only the main doping material, and the energy is instantly and concentratedly transferred from the main material to the main doping material. The collision probability of the T1 exciton of the main doping material is large, the damage to the material is large, and the life of the stacked device is low. However, after the auxiliary doping material is introduced, the auxiliary doping material can share part of the energy, so that the energy will not be too concentrated on the main doping material, which is equivalent to improving the dispersibility of the main doping material.

[0056] It should be further explained that with the improvement of the dispersion of the main material and the main doping material, the collision probability of triplet excitons will be greatly reduced, thereby reducing the damage to the material after the exciton collision, thereby extending the life of the device; at the same time, the triplet excitons that emit light in a radiative manner will increase, thereby further improving the efficiency and life of the device.

[0057] In some embodiments of the present application, the first electrode may be an anode electrode, and the second electrode may be a cathode electrode.

[0058] In some embodiments of the present application, the plurality of light-emitting units include at least a first light-emitting unit and a second light-emitting unit, the first light-emitting unit is disposed between the first electrode and the second light-emitting unit, and the electron blocking common layer is disposed between the first electrode and the first light-emitting unit. The electron blocking common layer is disposed close to the first electrode, which helps to effectively block the electrons transmitted from above, so that the electrons are confined within the light-emitting unit, so as to prevent the electrons from overflowing the light-emitting unit when a large current density is injected, thereby helping to improve the light-emitting efficiency of the stacked device.

[0059] In some embodiments of the present application, the first light-emitting unit includes a first I light-emitting layer, a first II light-emitting layer, and a first III light-emitting layer having different light-emitting colors, and the orthographic projection of the electron blocking common layer on the substrate at least covers the orthographic projections of the first I light-emitting layer, the first II light-emitting layer, and the first III light-emitting layer on the substrate.

[0060] In some embodiments of the present application, the second light-emitting unit includes a second I light-emitting layer, a second II light-emitting layer and a second III light-emitting layer. A first electron blocking layer corresponding to the second I light-emitting layer, a second electron blocking layer corresponding to the second II light-emitting layer and a third electron blocking layer corresponding to the second III light-emitting layer are arranged between the second light-emitting unit and the charge generation layer; the electron blocking common layer and the third electron blocking layer are of the same layer and material. The first light-emitting unit of the present application has a different structure from the second light-emitting unit. The electron blocking layers of the three primary colors of the second light-emitting unit correspond to the three primary color pixels of the light-emitting layer respectively, while the electron blocking layer of the first light-emitting unit adopts an electron blocking common layer, thereby achieving the purpose of simplifying the structure.

[0061] In some embodiments of the present application, the first electron blocking layer is set as a red electron blocking layer, the second electron blocking layer is set as a green electron blocking layer, and the third electron blocking layer and the electron blocking common layer are both set as blue electron blocking layers. Using the blue electron blocking layer as the electron blocking common layer can effectively prevent pixel crosstalk between red light pixels and green light pixels, which helps to improve the clarity and contrast of the stacked device.

[0062] It should be noted that the difficulty of electron injection is related to the depth of the LOMO energy level. The deeper the LOMO energy level, the easier it is to inject electrons, and the shallower the LOMO energy level, the more difficult it is to inject electrons. The difficulty of hole injection is related to the depth of the HOMO energy level. The shallower the HOMO energy level, the easier it is for holes to be spontaneously injected and transmitted, and the deeper the HOMO energy level, the more difficult it is to inject and transmit holes.

[0063] In some embodiments of the present application, the LOMO energy level of the main material is greater than the LOMO energy level of the auxiliary doping material, and the LOMO energy level of the auxiliary doping material is greater than the LOMO energy level of the main doping material.

[0064] In some embodiments of the present application, the absolute value of the difference between the LOMO energy levels of the main material and the auxiliary doping material, and between the auxiliary doping material and the main doping material is greater than 0.1 eV.

[0065] In some embodiments of the present application, the HOMO energy level of the main material is lower than the HOMO energy level of the auxiliary doping material, and the HOMO energy level of the auxiliary doping material is lower than the HOMO energy level of the main doping material.

[0066] In some embodiments of the present application, the absolute value of the difference between the HOMO energy levels of the main material and the auxiliary doping material, and between the auxiliary doping material and the main doping material is greater than 0.1 eV.

[0067] It should be noted that in the stacked device of the embodiment of the present application, the absolute value of the difference between the LOMO energy levels of the main material and the auxiliary doping material, and the auxiliary doping material and the main doping material is greater than 0.1eV, and the absolute value of the difference between the HOMO energy levels of the main material and the auxiliary doping material, and the auxiliary doping material and the main doping material is greater than 0.1eV. If the electron volt is too small, especially less than 0.1eV, the injection effect of electrons or holes is difficult to reflect.

[0068] In some embodiments of the present application, the thickness of the electron blocking common layer ranges from 5 nm to 8 nm. The thickness of the electron blocking common layer is relatively thin, thereby avoiding the problem of affecting the luminous efficiency due to uneven thickness.

[0069] In some embodiments of the present application, the thickness of the red light emitting layer ranges from 40nm to 50nm, the thickness of the green light emitting layer ranges from 35nm to 45nm, and the thickness of the blue light emitting layer ranges from 15nm to 25nm. The thickness of the light emitting layer is moderate. If the thickness of the light emitting layer is too large, the driving voltage may increase, which may reduce the stability of the device during operation.

[0070] In some embodiments of the present application, the main doping material and the auxiliary doping material include at least one of platinum series-platinum series, platinum series-iridium series, iridium series-platinum series, iridium series-iridium series, or osmium series-osmium series.

[0071] It should be noted that the main doping material and the auxiliary doping material can be selected from the platinum series and the iridium series. If the osmium series is selected as the doping material, both the main doping material and the auxiliary doping material must be selected from the osmium series.

[0072] In some embodiments of the present application, the main material adopts the following molecular structure:

[0073]

[0074] In some embodiments of the present application, the main doping material includes at least the following molecular structure:

[0075]

[0076] In some embodiments of the present application, the auxiliary doping material includes at least the following molecular structure:

[0077] In some embodiments of the present application, the doping concentration of the main material in the light-emitting unit ranges from 80wt% to 99.8wt%, the doping concentration of the main doping material in the light-emitting unit ranges from 0.1wt% to 10wt%, and the doping concentration of the auxiliary doping material in the light-emitting unit ranges from 0.1wt% to 10wt%.

[0078] In some embodiments of the present application, the doping concentration of the main material in the light-emitting unit ranges from 80wt% to 99.4wt%, the doping concentration of the main doping material in the light-emitting unit ranges from 0.1wt% to 10wt%, and the doping concentration of the auxiliary doping material in the light-emitting unit ranges from 0.5wt% to 10wt%.

[0079] In some embodiments of the present application, the doping concentration of the main material in the light-emitting unit ranges from 80wt% to 98.9wt%, the doping concentration of the main doping material in the light-emitting unit ranges from 0.1wt% to 10wt%, and the doping concentration of the auxiliary doping material in the light-emitting unit ranges from 1wt% to 10wt%.

[0080] refer to Figure 2 , a stacked device according to an embodiment of the present application includes:

[0081] A first electrode 10 is disposed on one side of the substrate;

[0082] The first light-emitting unit 21 includes a first I light-emitting layer 211, a first II light-emitting layer 212 and a first III light-emitting layer 213, wherein the first I light-emitting layer 211, the first II light-emitting layer 212 and the first III light-emitting layer 213 are arranged on a side of the first electrode 10 away from the substrate, and the orthographic projections of the first I light-emitting layer 211, the first II light-emitting layer 212 and the first III light-emitting layer 213 on the substrate at least cover the orthographic projection of the first electrode 10 on the substrate;

[0083] The charge generation layer 30 is disposed on a side of the first light emitting unit 21 away from the first electrode 10;

[0084] The second light-emitting unit 22 includes a second I light-emitting layer 221, a second II light-emitting layer 222 and a second III light-emitting layer 223, wherein the second I light-emitting layer 221, the second II light-emitting layer 222 and the second III light-emitting layer 223 are arranged on a side of the charge generation layer 30 away from the first light-emitting unit 21, and the orthographic projections of the second I light-emitting layer 221, the second II light-emitting layer 222 and the second III light-emitting layer 223 on the substrate at least cover the orthographic projection of the charge generation layer 30 on the substrate;

[0085] The second electrode 40 is disposed on a side of the second light emitting unit 22 away from the charge generation layer 30;

[0086] Wherein, an electron blocking common layer 50 is disposed between the first electrode 10 and the first light emitting unit 21, and the orthographic projection of the electron blocking common layer 50 on the substrate covers the orthographic projection of the first light emitting unit 21 on the substrate;

[0087] An electron blocking layer 60 is arranged between the charge generation layer 30 and the second light-emitting unit 22, including a first electron blocking layer 61, a second electron blocking layer 62 and a third electron blocking layer 63. The orthographic projections of the first electron blocking layer 61, the second electron blocking layer 62 and the third electron blocking layer 63 on the substrate cover the orthographic projection of the charge generation layer 30 on the substrate.

[0088] It is understandable that the stacked device can also add some functional layers conventionally used in stacked devices to help improve the performance of the stacked device, such as a hole injection layer, a hole transport layer, an electron transport layer, an electron blocking layer, a hole blocking layer, an electron injection layer, a covering layer, etc.

[0089] It can be understood that the materials of each layer of the stacked device can be adjusted according to the light-emitting requirements of the light-emitting device.

[0090] In some embodiments of the present application, the first electrode and the second electrode are electrodes known in the art for light-emitting devices, for example, they may independently include but are not limited to doped metal oxide electrodes, composite electrodes, graphene electrodes, carbon nanotube electrodes, metal single-substance electrodes or alloy electrodes. The material of the doped metal oxide electrode may include but is not limited to one or more of indium-doped tin oxide (ITO), fluorine-doped tin oxide (FTO), antimony-doped tin oxide (ATO), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), indium-doped zinc oxide (IZO), magnesium-doped zinc oxide (MZO), aluminum-doped magnesium oxide (AMO), and cadmium-doped zinc oxide. The composite electrode is an electrode formed by stacking two or more layers of conductive materials, such as AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO2 / Ag / TiO2, TiO2 / Al / TiO2, ZnS / Ag / ZnS, ZnS / Al / ZnS, Ca / Al, LiF / Ca, LiF / Al, BaF2 / Al, CsF / Al, CaCO3 / Al, BaF2 / Ca / Al, etc., where " / " represents a stacked structure, for example, AZO / Ag / AZO represents a composite electrode including a sequentially stacked AZO layer, an Ag layer, and an AZO layer. The material of the metal single substance electrode may include, but is not limited to, one or more of Ag, Ni, Pt, Au, Ir, Cu, Mo, Al, Ca, Mg, and Ba. Alloy electrodes include, but are not limited to, Au:Mg alloy electrodes and Ag:Mg alloy electrodes.

[0091] In some embodiments of the present application, the anode is an electrode with a relatively high work function, for example, it may include but is not limited to a doped metal oxide electrode with a relatively high work function, a metal single substance electrode with a relatively high work function, and a carbon nanotube electrode. The metal single substance electrode with a relatively high work function may be selected from but is not limited to Ni, Pt, Au, Ag, Ir, etc.

[0092] In some embodiments of the present application, the cathode is an electrode with a relatively low work function, for example, it may include but is not limited to a metal single substance electrode with a relatively low work function, a composite electrode with a relatively low work function, and an alloy electrode with a relatively low work function. The metal single substance electrode with a relatively low work function may be Ca, Ba, Al, Mg, etc. The composite electrode with a relatively low work function may be Ca / Al, LiF / Ca, LiF / Al, BaF2 / Al, CsF / Al, CaCO3 / Al, BaF2 / Ca / Al, etc. The alloy electrode with a relatively low work function may be Au:Mg and Ag:Mg, etc.

[0093] In some embodiments of the present application, the material of the light-emitting layer may include, but is not limited to, one or more of an organic light-emitting material and a quantum dot light-emitting material.

[0094] The organic light-emitting material may include, but is not limited to, CBP:Ir(mppy)3(4,4'-bis(N-carbazole)-1,1'-biphenyl:tri[2-(p-tolyl)pyridine iridium(III)), TCTX:Ir(mmpy)(4,4',4"-tri(carbazole-9-yl)triphenylamine:tri[2-(p-tolyl)pyridine iridium), diaromatic anthracene derivatives, distilbene aromatic derivatives, pyrene derivatives, fluorene derivatives, TBPe fluorescent materials, TTPX fluorescent materials, TBRb fluorescent materials, DBP fluorescent materials, delayed fluorescent materials, TTA materials, TADF (thermally activated delay) materials, polymers containing covalent bonds of BN, HLCT (hybridized localized charge transfer excited state) materials, Exciplex (exciplex) light-emitting materials, polyacetylene and its derivatives, polyparaphenylene and its derivatives, polythiophene and its derivatives, polyfluorene and its derivatives.

[0095] The quantum dot light-emitting material may include, but is not limited to, one or more of single structure quantum dots, core-shell structure quantum dots and perovskite semiconductor materials.

[0096] The materials of single structure quantum dots, the core materials of core-shell structure quantum dots and the shell materials of core-shell structure quantum dots may respectively include but are not limited to one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds and I-III-VI group compounds. The II-VI Group compounds may include, but are not limited to, one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe. The IV-VI Group compounds may include, but are not limited to, one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe. The III-V compounds may include, but are not limited to, one or more of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, and InAlPSb. The I-III-VI compounds may include, but are not limited to, one or more of CuInS2, CuInSe2, and AgInS2.

[0097] As an example, the core-shell structured quantum dots may include, but are not limited to, one or more of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS and InP / ZnSe / ZnS.

[0098] Perovskite semiconductor materials may include but are not limited to doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors. The general structural formula of inorganic perovskite semiconductors is AMX3, where A is Cs + ions, M is a divalent metal cation, including Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion, including Cl - Br - ,I - The general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation, including CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion, including Cl - Br - ,I - One or more of .

[0099] In some embodiments of the present application, the material of the hole transport layer can be a material known in the art for the hole transport layer, for example, it can be selected from but not limited to 4,4'-N,N'-dicarbazolyl-biphenyl (CBP), poly [bis (4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA), N,N'-diphenyl-N,N'-bis (1-naphthyl) -1,1'-biphenyl-4,4"-diamine (α-NPD), N,N'-diphenyl-N,N'-bis (3-methylphenyl) -(1,1'-biphenyl) -4,4'-diamine (TPD), poly (N,N'-bis (4-butylphenyl) -N,N'-bis (phenyl) benzidine) (Poly-TPD), N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro(spiro-TPD), N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine (DNTPD), 4,4',4'-tri(N-carbazolyl)-triphenylamine (TCTA), 4,4',4'-tri(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA), poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))] (TFB), poly(N-vinylcarbazole) (PVK) and its derivatives, N,N'-di(1-naphthyl)-N,N' -diphenyl-1,1'-biphenyl-4-4'-diamine (NPB), spiro NPB, poly(phenylene vinylene) (PPV), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV), poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene] (MOMO-PPV), 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (spiro-omeTAD), 4,4'-cyclohexylbis[N,N-di(4-methylphenyl)aniline] (TAPC), 1,3-bis(carbazol-9-yl)benzene (M CP), polyaniline, polypyrrole, poly(p-)phenylene vinylene, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT:PSS and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, doped graphene, undoped graphene, C60, doped or undoped NiO, doped or undoped MoO3, doped or undoped WO3, doped or undoped V2O5, doped or undoped P-type gallium nitride, doped or undoped CrO3, doped or undoped CuO. One or more of the following.

[0100] In some embodiments of the present application, the material of the electron transport layer is a material known in the art for the electron transport layer, for example, it can be selected from but not limited to one or more of inorganic electron transport materials and organic electron transport materials. Inorganic electron transport materials include but are not limited to doped metal oxide particles, undoped metal oxide particles, ceramic semiconductor materials, IIB-VIA semiconductor materials, IIIA-VA semiconductor materials and IB-IIIA-VIA semiconductor materials. The metal oxide in the undoped metal oxide particles includes but is not limited to one or more of ZnO, TiO2, SnO2, ZrO2, and Ta2O5. The metal oxides in the doped metal oxides include but are not limited to one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, and Al2O3. The doping elements in the doped metal oxides include but are not limited to one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, and Sn. For example, the doped metal oxides may be aluminum zinc oxide (AZO), lithium-doped zinc oxide (LZO), magnesium-doped zinc oxide (MZO), and tin-doped zinc oxide (Sn-ZnO). Ceramic semiconductor materials include but are not limited to barium titanate. IIB-VIA semiconductor materials include but are not limited to one or more of ZnS, ZnSe, and CdS. IIIA-VA semiconductor materials include but are not limited to one or more of InP and GaP. IB-IIIA-VIA semiconductor materials include but are not limited to one or more of CuInS and CuGaS.

[0101] The organic electron transport material includes, but is not limited to, one or more of quinoxaline compounds, imidazole compounds, triazine compounds, fluorene compounds, and hydroxyquinoline compounds.

[0102] The metal oxide particles include, but are not limited to, one or more of doped metal oxide particles and undoped metal oxide particles. The material of the undoped metal oxide particles includes, but is not limited to, one or more of ZnO, TiO2, SnO2, ZrO2, and Ta2O5. The metal oxide in the doped metal oxide particles includes, but is not limited to, one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, and Al2O3, and the doping elements in the doped metal oxide particles include, but are not limited to, one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, and Ga. As an example, the material of the doped metal oxide particles can be aluminum zinc oxide (AZO), lithium-doped zinc oxide (LZO), and magnesium-doped zinc oxide (MZO).

[0103] In some embodiments of the present application, the material of the hole injection layer can be a material known in the art for the hole injection layer, for example, it can be selected from but not limited to 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HAT-CN), PEDOT, PEDOT:PSS, PEDOT:PSS doped with s-MoO3 derivatives (PEDOT:PSS:s-MoO3), 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA), tetracyanoquinodimethane (F4-TCQN), copper phthalocyanine, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, molybdenum sulfide, tungsten sulfide and copper oxide. One or more.

[0104] In some embodiments of the present application, the stacked device further includes a substrate, which is disposed on a side of the anode electrode away from the light-emitting unit, or the substrate is disposed on a side of the cathode electrode away from the light-emitting unit.

[0105] The substrate may be a rigid substrate or a flexible substrate. In some embodiments of the present application, the material of the substrate may include but is not limited to one or more of glass, silicon wafer, polycarbonate, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, polyamide and polyether sulfone.

[0106] It can be understood that the stacked device can be a positive light emitting device or an inverted light emitting device. The stacked device can be a quantum dot light emitting device or an organic light emitting device.

[0107] According to a second aspect of the present application, a display device is provided, which includes the aforementioned stacked device.

[0108] The display device can be any electronic product with a display function, including but not limited to smart phones, tablet computers, laptops, digital cameras, digital video cameras, smart wearable devices, smart weighing electronic scales, car displays, televisions or e-book readers, among which smart wearable devices can be, for example, smart bracelets, smart watches, virtual reality (VR) helmets, etc.

[0109] The present application is described in detail below by means of specific examples, which are only partial examples of the present application and are not intended to limit the present application. The raw materials used in the following examples are all commercially available products unless otherwise specified.

[0110] Example 1

[0111] Referring to Table 1, a stacked device is provided, including:

[0112] an anode electrode, disposed on the substrate;

[0113] A hole injection layer is arranged on the side of the anode electrode facing away from the substrate;

[0114] A hole transport layer is disposed on a side of the hole injection layer away from the anode electrode;

[0115] A blue electron blocking layer 1 is arranged on a side of the hole transport layer away from the hole injection layer, and the orthographic projection of the blue electron blocking layer 1 on the substrate covers the orthographic projection of the anode electrode on the substrate;

[0116] A first light-emitting unit comprises a red light-emitting layer 1, a green light-emitting layer 1 and a blue light-emitting layer 1, wherein the red light-emitting layer 1, the green light-emitting layer 1 and the blue light-emitting layer 1 are arranged adjacent to each other in sequence, and the orthographic projections of the red light-emitting layer 1, the green light-emitting layer 1 and the blue light-emitting layer 1 on the substrate cover the orthographic projection of the blue electron blocking layer 1 on the substrate;

[0117] The hole blocking layer 1 is arranged on a side of the first light-emitting unit away from the blue electron blocking layer 1;

[0118] The electron transport layer 1 is arranged on a side of the hole blocking layer 1 away from the first light-emitting unit;

[0119] An n-type charge generation layer is arranged on a side of the electron transport layer 1 away from the hole blocking layer 1;

[0120] A p-type charge generation layer is arranged on a side of the n-type charge generation layer away from the electron transport layer 1;

[0121] The hole transport layer 2 is arranged on the side of the p-type charge generation layer away from the n-type charge generation layer;

[0122] An electron transport layer, comprising a red electron blocking layer 2, a green electron blocking layer 2 and a blue electron blocking layer 2, wherein the red electron blocking layer 2, the green electron blocking layer 2 and the blue electron blocking layer 2 are arranged adjacent to each other in sequence, and the orthographic projections of the red light-emitting layer 2, the green light-emitting layer 2 and the blue light-emitting layer 2 on the substrate cover the orthographic projection of the blue electron blocking layer 2 on the substrate;

[0123] The second light-emitting unit comprises a red light-emitting layer 2, a green light-emitting layer 2 and a blue light-emitting layer 2, wherein the red light-emitting layer 2, the green light-emitting layer 2 and the blue light-emitting layer 2 are arranged adjacent to each other in sequence, and the orthographic projections of the red light-emitting layer 2, the green light-emitting layer 2 and the blue light-emitting layer 2 on the substrate cover the orthographic projection of the blue electron blocking layer 2 on the substrate;

[0124] The hole blocking layer 2 is arranged on a side of the second light emitting unit away from the hole transport layer 2;

[0125] The electron transport layer 2 is arranged on a side of the hole blocking layer 2 away from the second light-emitting unit;

[0126] The electron injection layer is arranged on the side of the electron transport layer 2 away from the hole blocking layer 2;

[0127] A cathode electrode is arranged on a side of the electron injection layer away from the electron transport layer 2;

[0128] Table 1

[0129]

[0130] The red light emitting layer 1, the green light emitting layer 1, the red light emitting layer 2 and the green light emitting layer 2 use materials and doping concentrations as shown in Table 2:

[0131] Table 2

[0132]

[0133]

[0134] Comparative Example 1

[0135] A stacked device, which differs from Example 1 in that the structures of the film layers are as shown in Table 3:

[0136] Table 3

[0137]

[0138]

[0139] Comparative Example 2:

[0140] A stacked device, which differs from Example 1 in that no auxiliary doping material is added to the red light-emitting layer 1, the green light-emitting layer 1, the red light-emitting layer 2 and the green light-emitting layer 2, the doping concentration of the main material is kept unchanged, and the concentration of the main doping material is increased to 10wt%.

[0141] Sample preparation and testing:

[0142] Preparation method of the stacked device: Under high vacuum conditions, the functional layers from the hole injection layer to the cathode electrode and the covering layer shown in the above-mentioned stacked device are sequentially evaporated on the cleaned and dried TFT backplane substrate, and then chemical vapor deposition and inkjet printing are used for flexible packaging. After that, the samples are subjected to unit cutting and module production processes, and then corresponding optical tests and life tests are carried out.

[0143] The samples of the embodiment and the comparative example are lit at the same brightness using corresponding lighting devices, the brightness value of the white light 255 grayscale picture of the samples is tested using a brightness meter, the cathode output current value of the white light 255 grayscale picture of the samples is tested using a multimeter, and the white light 255 grayscale luminous efficiency and power consumption of the samples are calculated according to the formula.

[0144] The samples of the embodiment and the comparative example are lit at the same brightness using corresponding lighting equipment for a long time, and the brightness, current and other information of the samples are collected every hour. The time for the brightness to decay to 95% of the initial brightness is recorded as the brightness life of the sample.

[0145] The test results of the optical test and life test are shown in Table 4.

[0146] Table 4

[0147] sample Number of masks efficiency(%) Power consumption (%) life Example 1 9 105 94％ 132％ Comparative Example 1 10 100％ 100％ 100％ Comparative Example 2 9 100％ 100％ 71％

[0148] Combining Example 1, Comparative Examples 1-2 and Table 4, it can be seen that Comparative Example 1 is a traditional stacked device. Compared with Comparative Example 1, the efficiency of the stacked device of Example 1 of the present application is increased to 10%, the power consumption is reduced to 94%, and the service life is extended to 132%. It can be seen that the stacked device of Example 1 of the present application has improved the luminous efficiency and service life on the basis of simplifying the device structure; Comparative Example 2 is a stacked device with a simplified structure, but because the energy level of the blue electron blocking layer is deeper and the blocking effect on holes is stronger, the holes in the light-emitting layer of the red pixel and the green pixel are insufficient, which affects the service life. In addition, the sample of Example 1 of the present application can also reduce one mask plate, reducing the process cost.

[0149] The above is a detailed introduction to the stacked device and display device provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A stacked device, characterized in that: include: A first electrode is disposed on one side of the substrate; A plurality of light-emitting units are arranged on a side of the first electrode facing away from the substrate; A charge generation layer is disposed between adjacent light-emitting units; A second electrode is disposed on a side of the charge generation layer away from the first electrode; Wherein, an electron blocking common layer is provided between at least one of the light-emitting units and the first electrode, and the orthographic projection of the electron blocking common layer on the substrate at least covers the orthographic projection of the light-emitting unit on the substrate; At least one of the light-emitting units includes a main material, a main doping material and an auxiliary doping material, and the energy level of the auxiliary doping material is between the energy level of the main material and the energy level of the main doping material.

2. The stacked device according to claim 1, characterized in that: The plurality of light-emitting units at least include a first light-emitting unit and a second light-emitting unit, the first light-emitting unit is disposed between the first electrode and the second light-emitting unit, and the electron blocking common layer is disposed between the first electrode and the first light-emitting unit.

3. The stacked device according to claim 2, characterized in that: The first light-emitting unit includes a first I light-emitting layer, a first II light-emitting layer and a first III light-emitting layer with different light-emitting colors, and the orthographic projection of the electron blocking common layer on the substrate at least covers the orthographic projections of the first I light-emitting layer, the first II light-emitting layer and the first III light-emitting layer on the substrate.

4. The stacked device according to claim 2, characterized in that: The second light-emitting unit includes a second I light-emitting layer, a second II light-emitting layer and a second III light-emitting layer; a first electron blocking layer corresponding to the second I light-emitting layer, a second electron blocking layer corresponding to the second II light-emitting layer and a third electron blocking layer corresponding to the second III light-emitting layer are arranged between the second light-emitting unit and the charge generation layer; the electron blocking common layer and the third electron blocking layer are of the same layer and material.

5. The stacked device according to claim 4, characterized in that: The first electron blocking layer is configured as a red electron blocking layer, the second electron blocking layer is configured as a green electron blocking layer, and the third electron blocking layer and the electron blocking common layer are both configured as blue electron blocking layers.

6. The stacked device according to claim 1, characterized in that: The thickness of the electron blocking common layer ranges from 5 nm to 8 nm.

7. The stacked device according to claim 1, characterized in that: The LOMO energy level of the main material is greater than the LOMO energy level of the auxiliary doping material, and the LOMO energy level of the auxiliary doping material is greater than the LOMO energy level of the main doping material.

8. The stacked device according to claim 7, characterized in that: The absolute value of the difference between the LOMO energy levels of the main material and the auxiliary doping material, and between the auxiliary doping material and the main doping material is greater than 0.1 eV.

9. The stacked device according to claim 1, characterized in that: The HOMO energy level of the main material is lower than the HOMO energy level of the auxiliary doping material, and the HOMO energy level of the auxiliary doping material is lower than the HOMO energy level of the main doping material.

10. The stacked device according to claim 9, characterized in that: The absolute value of the difference between the HOMO energy levels of the main material and the auxiliary doping material, and between the auxiliary doping material and the main doping material is greater than 0.1 eV.

11. The stacked device according to claim 1, characterized in that: The main doping material and the auxiliary doping material include at least one of platinum series-platinum series, platinum series-iridium series, iridium series-platinum series, iridium series-iridium series or osmium series-osmium series.

12. The stacked device according to claim 1, characterized in that: The main doping material at least includes the following molecular structure:

13. The stacked device according to claim 1, characterized in that: The auxiliary doping material at least includes the following molecular structure:

14. The stacked device according to claim 1, characterized in that: The doping concentration of the main material in the light-emitting unit ranges from 80wt% to 99.8wt%, the doping concentration of the main doping material in the light-emitting unit ranges from 0.1wt% to 10wt%, and the doping concentration of the auxiliary doping material in the light-emitting unit ranges from 0.1wt% to 10wt%.

15. A display device, characterized in that: The display device comprises the stacked device according to any one of claims 1 to 14.

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