Organic light-emitting device, display panel and display device

Abstract

The invention discloses an organic light-emitting device, a display panel and a display device.The organic light-emitting device comprises a substrate, a light-emitting layer is arranged on the substrate, the doping concentration from the center position to the peripheral edge position of the light-emitting layer is sequentially reduced, and the light-emitting layer comprises a host material and a guest material; the doping concentration is the mass ratio of the guest material in the host material; or / and the thickness of the light-emitting layer from the center position to the peripheral edge position is sequentially reduced, and the thickness is the thickness of the light-emitting layer in the direction perpendicular to the plane where the substrate is located. According to the organic light-emitting device, the light-emitting layers with different doping concentrations or / and thicknesses are formed at different positions of the substrate, so that the display uniformity of the organic light-emitting device can be improved, and the service life of the organic light-emitting device can be prolonged.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an organic light emitting device, a display panel and a display apparatus. Background Art

[0002] Existing organic light-emitting diodes (OLEDs) are usually produced by evaporation. Among them, the evaporation source of cathode evaporation is mostly a point source. The point source is at different distances from the center and edge of the evaporation substrate, resulting in different temperatures at the center and edge of the substrate. The closer to the point source, the higher the substrate temperature. The uneven temperature at each position of the substrate affects the life of the substrate. The higher the temperature, the shorter the life. After long-term operation, the color deviation in the middle area of ​​the display panel will be more serious than that in the edge area, and the yellowing phenomenon in the center area will be more serious. Summary of the invention

[0003] The purpose of the present disclosure is to provide an organic light-emitting device, a display panel and a display apparatus, which are at least used to improve the problem of severe color deviation of the organic light-emitting device.

[0004] To achieve the above objectives, the embodiments of the present disclosure provide the following technical solutions: In one aspect, an organic light-emitting device is provided, comprising: a substrate, a light-emitting layer is disposed on the substrate, the doping concentration of the light-emitting layer decreases from the center position to the peripheral edge position, the light-emitting layer comprises a host material and a guest material, and the doping concentration is the mass proportion of the guest material in the host material; Or / and, the thickness of the light-emitting layer decreases from the center to the edges thereof, and the thickness is the thickness of the light-emitting layer in a direction perpendicular to the plane where the substrate is located.

[0005] In addition, the organic light-emitting device of the present application may also have the following additional technical features: In some optional embodiments, the rate of decrease of the doping concentration from the center position to the peripheral edge positions of the light-emitting layer decreases successively.

[0006] In some optional embodiments, the doping concentration at the center of the light-emitting layer is 1.5% to 2.5%, and the doping concentration at the edges of the light-emitting layer is 0.5% to 1.5%.

[0007] In some optional embodiments, the thickness of the light-emitting layer at the center is 230Å~280Å, and the thickness of the light-emitting layer at the edges is 180Å~220Å.

[0008] In some optional embodiments, the organic light-emitting device further includes a pixel definition layer disposed on the substrate, the pixel definition layer includes a plurality of opening areas disposed at intervals, the light-emitting layer is disposed in each of the opening areas, and the light-emitting layer in at least some of the opening areas is a blue light-emitting layer.

[0009] In some optional embodiments, an anode is further arranged between the light-emitting layer and the substrate, and the anode is arranged one-to-one with the light-emitting layer in the opening area, and a thermal conductive layer is arranged on the side of the anode corresponding to the blue light-emitting layer close to the substrate.

[0010] In some optional embodiments, the projection of the heat-conducting layer on the substrate at least covers the projection of the anode corresponding to the blue light-emitting layer on the substrate.

[0011] On the other hand, a preparation device of an organic light-emitting device is provided, the preparation device is used to obtain the organic light-emitting device described in any embodiment of the present application, the preparation device comprises: a carrier, the carrier has a carrier cavity, the carrier cavity is used to place a material to be evaporated; The object carrier has a bottom wall and a top wall which are arranged opposite to each other, and a heating source is arranged outside the bottom wall of the object carrier, and the heating source is used to heat the material to be evaporated; A plurality of nozzles connected to the carrier cavity are arranged on the top wall of the carrier, and the nozzles are arranged at intervals from the center position of the top wall of the carrier to the edges of the four sides. The nozzles are used to spray the material to be evaporated after being heated by the heating source toward the organic light-emitting device to evaporate and form the light-emitting layer.

[0012] In some optional embodiments, the apertures of the plurality of nozzles located from the center of the top wall of the object carrier to the peripheral edges decrease in sequence.

[0013] In some optional embodiments, there are multiple heating sources, and the multiple heating sources are arranged at intervals from the center position of the bottom wall to the surrounding edges of the object carrier, and the heating power of the multiple heating sources located from the center position of the bottom wall to the surrounding edges of the object carrier is the same.

[0014] In some optional embodiments, the heating source includes a resistance wire, the resistance wire is in a zigzag shape or an arc shape, and the resistance wire covers the bottom wall of the carrier.

[0015] In some optional embodiments, the resistance wire includes a plurality of first straight line segments arranged in parallel and at intervals, a second straight line segment is connected between two endpoints of two adjacent first straight line segments located on the same side, and two adjacent second straight line segments are staggered; Alternatively, the resistance wire comprises a plurality of first straight line segments which are arranged in parallel and at intervals, a second straight line segment is connected between two end points of two adjacent first straight line segments located on opposite sides, and each of the second straight line segments is arranged in parallel; Alternatively, the resistance wire comprises a plurality of first arc segments which are arranged in parallel and at intervals, a second arc segment is connected between two end points of two adjacent first arc segments located on opposite sides, and each of the second arc segments is arranged in parallel.

[0016] On the other hand, a display panel is provided, comprising the organic light-emitting device described in any embodiment of the present application, or comprising a preparation device of the organic light-emitting device described in any embodiment of the present application or the obtained organic light-emitting device.

[0017] On the other hand, a display device is provided, comprising the display panel described in any embodiment of the present application.

[0018] The present disclosure provides an organic light-emitting device, a display panel and a display apparatus. In the organic light-emitting device, the doping concentration of the light-emitting layer decreases from the center position to the surrounding edge positions, or / and the thickness of the light-emitting layer decreases from the center position to the surrounding edge positions, thereby effectively improving the display uniformity and lifespan of the organic light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings required to be used in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the product involved in the embodiments of the present disclosure, the actual process of the method, the actual timing of the signal, etc.

[0020] Figure 1 It is a schematic diagram of the evaporation of the existing cathode metal evaporation source; Figure 2 It is a CIE locus diagram of existing organic light-emitting devices; Figure 3 A schematic diagram of a first structure of an organic light-emitting device provided according to the present disclosure; Figure 4 A CIE locus diagram of a first structure of an organic light-emitting device provided according to the present disclosure; Figure 5 is a schematic diagram of a second structure of an organic light-emitting device provided according to the present disclosure; Figure 6 A CIE locus diagram of a second structure of an organic light-emitting device provided according to the present disclosure; Figure 7is a schematic diagram of a third structure of an organic light-emitting device provided according to the present disclosure; Figure 8 A CIE locus diagram of a third structure of an organic light-emitting device provided according to the present disclosure; Fig. 9 A structural diagram of a device for preparing an organic light-emitting device according to the present disclosure; Fig.10 A first structural diagram of a heating source provided according to the present disclosure; Fig.11 is a second structural diagram of a heating source provided according to the present disclosure; Fig.12 is a third structural diagram of a heating source provided according to the present disclosure; Fig.13 is a structural diagram of a display panel provided according to the present disclosure; Fig.14 It is a structural diagram of a display device provided according to the present disclosure.

[0021] In the above picture: 10 organic light-emitting device; 11 substrate; 121 blue light-emitting layer; 122 red light-emitting layer; 123 green light-emitting layer; 13 pixel definition layer; 14 anode; 15 thermal conductive layer; 16 encapsulation layer; 20 object carrier; 30 heating source; 301 resistance wire; 40 nozzle; 50 cathode evaporation source; 100 display panel; 1000 display devices. DETAILED DESCRIPTION

[0022] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0023] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and other forms thereof, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open, inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics described may be included in any one or more embodiments or examples in any appropriate manner.

[0024] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0025] “At least one of A, B, and C” has the same meaning as “at least one of A, B, or C” and both include the following combinations of A, B, and C: A only, B only, C only, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B, and C.

[0026] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0027] It will be understood that when a layer or an element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present between the layer or element and the other layer or substrate.

[0028] Exemplary embodiments are described herein with reference to cross-sectional views and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of layers and regions are exaggerated for clarity. Therefore, variations in shape relative to the drawings due to, for example, manufacturing techniques and / or tolerances are contemplated. Therefore, exemplary embodiments should not be interpreted as being limited to the shapes of the regions shown herein, but rather include deviations in shape due to, for example, manufacturing.

[0029] At present, organic light-emitting devices 10 (Organic Electroluminesecent Display, OLED) have been applied to many fields such as mobile phones and TV displays due to their excellent performance such as high color saturation, wide viewing angle, thin thickness, and flexible bending. Existing OLED light-emitting devices are usually produced by evaporation. In the OLED evaporation of each film layer, the cathode evaporation source 50 is mostly carried out by a point source, such as Figure 1 As shown, however, point source evaporation has the following defects: the point source is at different distances from the center and edge of the evaporation substrate 11, resulting in different temperatures at the center and edge of the substrate 11. The closer the point source is to the point source, the higher the temperature of the substrate 11. During the evaporation process, the temperature of point A at the edge is 60°C, and the temperature of point B at the center is 70°C. Table 1 shows the brightness life of OLED devices evaporated at different substrate 11 temperatures. It can be seen from Table 1 that the temperature of the substrate 11 during evaporation has a significant effect on the device's blue light life, but has no effect on the red and green light lifespans. The higher the temperature, the shorter the blue light lifespan; wherein LT95-R represents the time for the red light to decrease from 100% of the initial brightness to 95%, LT95-G represents the time for the green light to decrease from 100% of the initial brightness to 95%, and LT95-B represents the time for the blue light to decrease from 100% of the initial brightness to 95%. As a result, for large-size display panels 100 (Large panel AMOLED), or panels evaporated in the middle area, the lifespan color deviation in the center area is more serious than that in the edge area under long-term operation, such as Figure 2 As shown in the chromaticity diagram of the center and edge positions of a large-size panel after running for 500 hours (Hrs), the center position is obviously more yellow, especially the blue light corresponding to the center position is more yellow, which greatly affects the display effect of the panel. Figure 2 As shown, the overall thickness of the existing blue light-emitting layer 121 is 200Å, and the doping concentration from the center to the surrounding edge positions is 1%. The experimental measurement shows that the color deviation of the center area is 2.7JNCD.

[0030] Table 1 Lifespan of organic light emitting device 10 corresponding to different substrate 11 temperatures

[0031] Based on this, Figure 3 and Figure 5 As shown, the present disclosure provides an organic light-emitting device 10, comprising: a substrate 11, on which a light-emitting layer is disposed, wherein the doping concentration of the light-emitting layer decreases from the center position to the peripheral edge positions, wherein the light-emitting layer comprises a host material and a guest material, and the doping concentration is the mass proportion of the guest material in the host material; Or / and, the thickness of the light-emitting layer decreases from the center to the edges thereof, and the thickness is the thickness of the light-emitting layer along a direction perpendicular to the plane where the substrate 11 is located.

[0032] A light-emitting layer is disposed on the substrate 11, and the light-emitting layer includes a host material and a guest material, wherein the mass ratio of the guest material to the host material is the doping concentration of the light-emitting layer, such as Figure 3 As shown, the doping concentration of the light-emitting layer decreases from the center position of the light-emitting layer to the surrounding edge positions, that is, the doping concentration of the light-emitting layer decreases from the center position of the light-emitting layer to the surrounding edge positions, and the doping concentration at the center position of the light-emitting layer is the highest, and the doping concentration at the surrounding edge positions is the lowest. The higher the doping concentration, the smaller the color deviation of the corresponding organic light-emitting device 10. By differentiating the doping concentrations at different positions of the light-emitting layer, the problem of color deviation of the organic light-emitting device 10 is solved, the color deviation of each position of the organic light-emitting device 10 is kept consistent, and the display uniformity and life of the organic light-emitting device 10 are improved.

[0033] Or, if Figure 5 As shown, the thickness of the light-emitting layer decreases from the center position to the edge positions, that is, the thickness of the light-emitting layer decreases from the center position to the edge positions, and the thickness at the center position of the light-emitting layer is the highest, and the thickness at the edge positions is the lowest. The higher the thickness, the smaller the corresponding color deviation. By differentiating the thickness of the light-emitting layer at different positions, the color deviation problem of the organic light-emitting device 10 is solved, the color deviation of each position of the organic light-emitting device 10 is kept consistent, and the display uniformity and life of the organic light-emitting device 10 are improved.

[0034] In the present disclosure, the doping concentration of the light-emitting layer can be gradually reduced from the center position to the surrounding edge positions, and the thickness of the light-emitting layer can be gradually reduced from the center position to the surrounding edge positions. The two methods can be combined to further improve the display uniformity and lifespan of the organic light-emitting device 10.

[0035] In the present disclosure, the light-emitting layer may be a blue light-emitting layer 121, a green light-emitting layer 123 or a red light-emitting layer 122, and the red light-emitting layer 122, the green light-emitting layer 123 and the blue light-emitting layer 121 all use a host material and a guest material. The host material can be divided into an N-type host material and a P-type host material, wherein the N-type host material refers to a material having excess electrons on a PN junction and mainly conducting with electrons; the P-type host material refers to a material lacking electrons on a PN junction and mainly conducting with holes.

[0036] For example, the host material (RH) of the red light-emitting layer 122 can be selected from DCM series materials, such as DCM, DCJTB, DCJTI, DCzDBT, etc.; the guest material (RD) of the red light-emitting layer 122 can be selected from metal complexes, such as Ir(piq)2(acac), PtOEP, Ir(btp)2(acac), etc. For example, if the host material (RH) of the red light-emitting layer 122 is DCzDBT, and the guest material (RD) of the red light-emitting layer 122 is Ir(piq)2(acac), the structural formulas of DCzDBT and Ir(piq)2(acac) are as follows:

[0037] DCzDBTIr(piq)2(acac) For example, the host material (GH) of the green light-emitting layer 123 can be selected from coumarin dyes, quinacridone copper derivatives, polycyclic aromatic hydrocarbons, diamine anthracene derivatives, carbazole derivatives, such as DMQA, BA-NPB, Alq3, CBP, etc.; the guest material (GD) of the green light-emitting layer 123 can be a metal complex, such as Ir(ppy)3, Ir(ppy)2(acac), etc. For example, the host material (GH) of the green light-emitting layer 123 is CBP, and the guest material (GD) of the green light-emitting layer 123 is Ir(ppy)3. The structural formulas of CBP and Ir(ppy)3 are as follows:

[0038] CBPIr(ppy)3 For example, the host material (BH) of the blue light-emitting layer 121 can be selected from anthracene derivatives ADN, MADN, etc.; the guest material (BD) of the blue light-emitting layer 121 can be selected from pyrene derivatives, fluorene derivatives, perylene derivatives, styrylamine derivatives, metal complexes, etc., such as TBPe, BDAVBi, DPAVBi, FIrpic, etc. For example, if the host material (BH) of the blue light-emitting layer 121 is ADN, and the guest material (BD) of the blue light-emitting layer 121 is DPAVBi, the structural formulas of ADN and DPAVBi are as follows:

[0039] ADNDPAVBi In some optional embodiments, the rate of decrease of the doping concentration from the center position to the peripheral edge positions of the light-emitting layer decreases successively.

[0040] Since the color deviation from the center position to the edge positions of the organic light-emitting device 10 decreases in sequence, that is, the color deviation in the center area is more serious, while the color deviation at the edge position is relatively small. In the present disclosure, the doping concentration from the center position to the edge positions of the light-emitting layer decreases nonlinearly, and the doping concentration from the center position to the edge positions of the light-emitting layer decreases at a faster rate first and then at a slower rate, so that the color deviation from the center position to the edge positions of the organic light-emitting device 10 is kept as consistent as possible, further improving the display uniformity and life of the organic light-emitting device 10.

[0041] In some optional embodiments, the doping concentration at the center of the light-emitting layer is 1.5% to 2.5%, and the doping concentration at the edges of the light-emitting layer is 0.5% to 1.5%.

[0042] The doping concentration at the center of the light-emitting layer is higher than the doping concentration at the edges, so that the color deviation of the organic light-emitting device 10 near the center is reduced, and the color deviation and life of the central area are improved. For example, the doping concentration at the center of the light-emitting layer is 1.5%, 2%, 2.5%, etc., and the doping concentration at the edges is 0.5%, 1%, 1.5%, etc.

[0043] For example, Figure 3 and Figure 4 As shown, the overall thickness of the blue light-emitting layer 121 of the present application is 200Å, the doping concentration at the center position is 2%, the doping concentration at the edge position is 1%, and the doping concentration of the blue light-emitting layer 121 decreases from the center position to the edge position. The chromaticity diagram of the display panel 100 formed after running for 500Hrs shows that the color deviation in the central area is reduced from 2.7JNCD to 1.2JNCD, which greatly improves the lifespan and display effect.

[0044] In some optional embodiments, the thickness of the light-emitting layer at the center is 230Å~280Å, and the thickness of the light-emitting layer at the edges is 180Å~220Å.

[0045] The thickness of the center of the light-emitting layer is higher than that of the peripheral edges, so that the color deviation of the organic light-emitting device 10 near the center is reduced, and the color deviation and life of the central area are improved. For example, the thickness of the center of the light-emitting layer is 230Å, 240Å, 250Å, 260Å, 270Å, 280Å, etc., and the thickness of the peripheral edges is 180Å, 190Å, 200Å, 210Å, 220Å, etc.

[0046] For example, Figure 5 and Figure 6As shown, the thickness of the blue light-emitting layer 121 at the center position of the present application is 250Å, the thickness at the edge position is 200Å, and the doping concentration from the center position to the surrounding edge positions of the blue light-emitting layer 121 is 1%, and the thickness of the blue light-emitting layer 121 decreases from the center position to the edge position. The chromaticity diagram of the display panel 100 formed after running for 500Hrs shows that the color deviation in the central area is reduced from 2.7JNCD to 1.4JNCD, which greatly improves the lifespan and display effect.

[0047] In some optional embodiments, such as Figure 7 As shown, the organic light-emitting device 10 also includes a pixel definition layer 13 arranged on the substrate 11, and the pixel definition layer 13 includes a plurality of opening areas arranged at intervals, and the light-emitting layer is arranged in each of the opening areas, and the light-emitting layer in at least part of the opening areas is a blue light-emitting layer 121.

[0048] The pixel definition layer 13 (PDL) is provided with a plurality of opening areas at intervals, and a light-emitting layer is provided in each opening area, and the light-emitting layer is any one of a blue light-emitting layer 121, a green light-emitting layer 123, or a red light-emitting layer 122. Preferably, the blue light-emitting layer 121 is provided in at least part of the opening areas, and the doping concentration of the blue light-emitting layer 121 decreases from the center position to the peripheral edge positions, or / and the thickness of the blue light-emitting layer 121 decreases from the center position to the peripheral edge positions, so as to effectively improve the color deviation of the blue light-emitting layer 121 and improve the display uniformity and life of the organic light-emitting device 10.

[0049] In some optional embodiments, such as Figure 7 As shown, an anode 14 is further arranged between the light-emitting layer and the substrate 11 , and the anode 14 is arranged one-to-one corresponding to the light-emitting layer in the opening area, and a heat-conducting layer 15 is arranged on the side of the anode 14 corresponding to the blue light-emitting layer 121 close to the substrate 11 .

[0050] The heat conducting layer 15 is selected from insulating organic or inorganic materials, wherein the organic materials include organic heat conducting silicone, organic silicone rubber system or epoxy system heat conducting glue, etc., and the inorganic materials include aluminum oxide, aluminum nitride or boron nitride, etc.

[0051] A heat conducting layer 15 is provided on the side of the anode 14 corresponding to the blue light emitting layer 121 close to the substrate 11. During the cathode evaporation process, the surface temperature of the anode 14 can be conducted away, thereby quickly lowering the temperature of the anode 14 and reducing the influence of the temperature on the blue light emitting layer, so that the blue light life at different positions remains consistent.

[0052] For example, Figure 7 and Figure 8As shown, the overall thickness of the blue light-emitting layer 121 is 200Å, and the doping concentration from the center position to the surrounding edge positions is 1%. A thermal conductive layer 15 is arranged under the anode 14 corresponding to the blue light-emitting layer 121, and the color deviation in the central area of ​​the blue light-emitting layer 121 is reduced from 2.7JNCD to 1.5JNCD.

[0053] It should be noted that a heat-conducting layer 15 is provided on the side of the anode 14 corresponding to the red light-emitting layer 122 and / or the green light-emitting layer 123 close to the substrate 11, which can also reduce the influence of temperature on the red light-emitting layer 122 and the green light-emitting layer 123, so that the lifespan of red light and green light at different positions remains consistent.

[0054] In some optional embodiments, such as Figure 7 As shown, the projection of the heat-conducting layer 15 on the substrate at least covers the projection of the anode 14 corresponding to the blue light-emitting layer 121 on the substrate.

[0055] The projection area of ​​the thermal conductive layer 15 on the substrate is larger than the projection area of ​​the anode 14 corresponding to the blue light-emitting layer 121 on the substrate, and the projection of the thermal conductive layer 15 on the substrate at least covers the projection of the anode 14 corresponding to the blue light-emitting layer 121 on the substrate, so that the contact area between the thermal conductive layer 15 and the anode 14 is maximized, the heat dissipation efficiency of the anode 14 is further improved, and the influence of temperature on the blue light-emitting layer 121 is reduced.

[0056] It can be understood that the organic light-emitting device 10 includes a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), a light-emitting layer (EML), a hole blocking layer (HBL), an electron transport layer (ETL), an electron injection layer (EIL), a cathode, etc., wherein the hole injection layer is arranged on the side of the anode 14 away from the substrate 11, the hole transport layer is arranged on the side of the hole injection layer away from the anode 14, the electron blocking layer is arranged on the side of the hole transport layer away from the hole injection layer, and the side of the electron blocking layer away from the hole transport layer forms the light-emitting layer, the side of the light-emitting layer away from the electron blocking layer forms a hole blocking layer, the side of the hole blocking layer away from the light-emitting layer forms an electron transport layer, the side of the electron transport layer away from the hole blocking layer forms an electron injection layer, and the side of the electron injection layer away from the electron transport layer forms a cathode. The thickness of the hole injection layer is 5~30 nm, the thickness of the hole transport layer is 100~2000 nm, the thickness of the electron blocking layer is 5~100 nm, the thickness of the hole blocking layer is 5~100 nm, the thickness of the electron transport layer is 20~100 nm, and the thickness of the electron injection layer is 1~10 nm.

[0057] For example, the substrate 11 may be a rigid substrate 11, and the rigid substrate 11 may include, for example, a glass substrate 11, a PMMA (Polymethyl methacrylate) substrate 11, a silicon substrate 11, etc. For another example, the substrate 11 may be a flexible substrate 11, and the flexible substrate 11 may include, for example, a PET (Polyethylene Terephthalate) substrate 11, a PEN (Polyethylene naphthalate dicarboxylic acid glycolester) substrate 11, or a PI (Polyimide) substrate 11, etc.

[0058] The anode 14 is a high work function electrode material, such as transparent oxide ITO, IZO; it can also be a composite electrode formed by ITO / Ag / ITO, Ag / IZO, CNT / ITO, CNT / IZO, GO / ITO, GO / IZO, etc.

[0059] The hole injection layer (HIL) can be made of inorganic oxides, including but not limited to molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, manganese oxide, etc.; it can also be a dopant of a strong electron-withdrawing system, including but not limited to F4TCNQ, HATCN, PPDN, etc.; and the hole transport material can also be P-type doped to form a hole injection layer by co-evaporation.

[0060] The hole transport layer (HTL) uses a material with good hole transport properties, which may be an aromatic amine or carbazole material, including but not limited to NPB, TPD, BAFLP, DFLDPBi, TCTA, TAPC, m-MTDATA, etc.

[0061] The electron blocking layer (EBL) uses aromatic amine or carbazole materials, including but not limited to CBP, PCzPA, etc.

[0062] Hole blocking layer (HBL) and electron transport layer (ETL) use aromatic heterocyclic compounds, such as imidazole derivatives such as benzimidazole derivatives, imidazopyridine derivatives, benzimidazolephenanthridine derivatives; oxazine derivatives such as pyrimidine derivatives and triazine derivatives; quinoline derivatives, isoquinoline derivatives, phenanthroline derivatives and other compounds containing nitrogen-containing six-membered ring structures (including compounds having phosphine oxide-based substituents on heterocyclic rings). Exemplarily, OXD-7, TAZ, p-EtTAZ, BPhen, BCP, TPBi, LIQ, etc. are used in HBL and ETL.

[0063] The electron injection layer (EIL) uses a material with the ability to transport electrons, has the effect of injecting electrons from the cathode and has excellent thin film forming ability, such as alkali metals or metals, including but not limited to LiF, Yb, Mg, Ca or their compounds.

[0064] The cathode preferably has a material with a low work function so that electrons can be easily injected into the organic layer, and has good light transmittance and conductivity. Specific examples of cathode materials that can be used in the present invention include: metals, metal oxides, and metal alloys, such as aluminum (Al), silver (Ag), gold (Au), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium (Li), potassium (K), sodium (Na), tin (Sn), titanium (Ti), lead (Pb), samarium (Sm), yttrium (Y), indium tin oxide (ITO), magnesium silver alloy (Mg:Ag), ytterbium gold alloy (Yb:Au), Ytterbium silver alloy (Yb:Ag), lithium aluminum alloy (Li:Al), lithium calcium magnesium alloy (Li:Ca:Al), etc.; and laminated materials, such as magnesium / aluminum (Mg / Al), magnesium / silver (Mg / Ag), aluminum / silver (Al / Ag), aluminum / gold (Al / Au), ytterbium / gold (Yb / Au), ytterbium / silver (Yb / Ag), calcium / magnesium (Ca / Mg), calcium / silver (Ca / Ag), barium / silver (Ba / Ag), etc., but not limited to these.

[0065] It should be noted that an encapsulation layer 16 (TFE) is provided on the side of the cathode away from the electron injection layer. The encapsulation layer 16 is generally obtained by alternating inorganic / organic / inorganic stacking, and can be a three-layer, five-layer, seven-layer or even more layer structure. In some examples, the encapsulation layer 16 may include a first inorganic encapsulation layer 16, an organic encapsulation layer 16, and a second inorganic encapsulation layer 16. The first inorganic encapsulation layer 16 and the second inorganic encapsulation layer 16 may be made of inorganic materials such as nitrides, oxides, nitrogen oxides, nitrates, carbides, or any combination thereof. For example, the first inorganic encapsulation layer 16 and the second inorganic encapsulation layer 16 are made of silicon nitride (SiN), silicon oxide (SiO), aluminum oxide (Al2O3), titanium dioxide (TiO2), etc. The preparation process may adopt a chemical vapor deposition (CVD) process, such as a plasma enhanced chemical vapor deposition (PECVD) process, or a plasma enhanced atomic layer deposition (PEALD) process. For example, the organic encapsulation layer 16 may be made of acrylic, hexamethyldisiloxane, polyacrylate, polycarbonate, polystyrene, epoxy and other materials, and the preparation process may adopt inkjet printing (IJP), sputtering, flash evaporation, screen printing, PECVD and other processes. Of course, in other examples, other packaging methods may also be used, such as inorganic thin film packaging, which is not limited in this embodiment. On the other hand, Fig. 9 As shown, a preparation device for an organic light-emitting device is provided, the preparation device is used to obtain the organic light-emitting device 10 described in any embodiment of the present application, the preparation device comprises: a carrier 20, the carrier 20 has a carrier cavity, the carrier cavity is used to place the material to be evaporated; The object carrier 20 has a bottom wall and a top wall that are arranged opposite to each other. A heating source 30 is arranged outside the bottom wall of the object carrier 20. The heating source 30 is used to heat the material to be evaporated. A plurality of nozzles 40 connected to the carrier cavity are disposed on the top wall of the carrier 20. The nozzles 40 are spaced from the center of the top wall to the edges of the carrier 20. The nozzles 40 are used to spray the material to be evaporated after being heated by the heating source 30 toward the organic light-emitting device 10 to form the light-emitting layer by evaporation.

[0066] Specifically, the materials to be evaporated can be the main material and the guest material corresponding to the red light-emitting layer 122, the blue light-emitting layer 121 and the green light-emitting layer 123, wherein the materials of the red light-emitting layer 122, the blue light-emitting layer 121 and the green light-emitting layer 123 are evaporated separately, and the main material and the guest material corresponding to the light-emitting layer of the same color are evaporated at the same time.

[0067] The heating source 30 heats the material to be evaporated in the carrier cavity, and the heated material to be evaporated is sprayed toward the substrate 11 through each nozzle 40 to form a corresponding light-emitting layer. A feed port may be provided in the carrier 20, and the feed port is connected to the carrier cavity so that the material to be evaporated is injected into the carrier cavity through the feed port; at least one partition may be provided in the carrier 20 to divide the carrier cavity into a plurality of different chambers, and different chambers are equipped with different materials to be evaporated, such as a host material and a guest material.

[0068] Each nozzle 40 (Nozzle) is arranged at intervals from the center position of the top wall to the edge positions of the surroundings of the object carrier 20. The injection rate of each nozzle 40 is controlled to form a light-emitting layer with a differentiated doping concentration and / or thickness at different positions on the substrate 11. For example, the injection rates of multiple nozzles 40 from the center position of the top wall to the edge positions are controlled to decrease in sequence, so that the injection rate of the nozzle 40 located at the center position of the top wall is the highest, and the injection rate of the nozzles 40 located at the edge positions is the lowest.

[0069] The organic light-emitting device preparation device provided in the embodiment of the present application has a simple structure and is mass-producible, and can form light-emitting layers with differentiated doping concentrations and / or thicknesses at different positions of the substrate 11, thereby improving the display uniformity of the organic light-emitting device 10 and increasing its lifespan.

[0070] In some optional embodiments, the apertures of the plurality of nozzles 40 located from the center of the top wall of the object carrier 20 to the peripheral edges thereof decrease in sequence.

[0071] The aperture sizes of the multiple nozzles 40 distributed from the center position of the top wall of the object carrier 20 to the surrounding edge positions tend to decrease. The aperture of the nozzle 40 located at the center position of the top wall is the largest, and the aperture of the nozzle 40 located at the surrounding edge positions of the top wall is the smallest, so that the nozzle 40 near the center area of ​​the top wall can spray the evaporated material at a higher rate, and the nozzle 40 near the surrounding edge positions of the top wall can spray the evaporated material at a lower rate, thereby forming a light-emitting layer with a thickness that decreases successively from the center position to the surrounding edge positions on the substrate 11, or / and, forming a light-emitting layer with a doping concentration that decreases successively from the center position to the surrounding edge positions on the substrate 11, and utilizing the rate difference to reduce the deviation of the color deviation at each position of the organic light-emitting device 10, thereby improving the display uniformity and life of the organic light-emitting device 10.

[0072] In some optional embodiments, such as Fig. 9 As shown, there are multiple heating sources 30, and the multiple heating sources 30 are arranged at intervals from the center position of the bottom wall to the surrounding edge positions of the object carrier 20, and the heating power of the multiple heating sources 30 located from the center position of the bottom wall to the surrounding edge positions of the object carrier 20 is the same.

[0073] A plurality of different heating sources 30 are used to realize independent heating control of different positions of the substrate 11 to meet different heating power requirements. For example, the heating power of the plurality of heating sources 30 distributed from the center position of the bottom wall of the object carrier 20 to the surrounding edge positions is the same, so that the heating temperature of each position of the substrate 11 is kept consistent, the deviation of the color deviation of the organic light-emitting device 10 and the surrounding edge positions is reduced, and the uniformity and life of the display of the organic light-emitting device 10 are further improved.

[0074] In some optional embodiments, such as Figures 10 to 12 As shown, the heating source 30 includes a resistance wire 301 , and the resistance wire 301 is in a broken line shape or an arc shape, and the resistance wire 301 covers the bottom wall of the object carrier 20 .

[0075] The heating source 30 can be one, and the heating source 30 includes a resistance wire 301 distributed in a zigzag or arc shape. The resistance wire 301 is evenly spread on the bottom wall of the object 20 to keep the heating temperature of each position of the substrate 11 consistent, reduce the color deviation of the organic light-emitting device 10 and the surrounding edge positions, and further improve the display uniformity and life of the organic light-emitting device 10.

[0076] In some optional embodiments, the resistance wire 301 includes a plurality of first straight line segments arranged in parallel and at intervals, a second straight line segment is connected between two endpoints of two adjacent first straight line segments located on the same side, and two adjacent second straight line segments are staggered; Alternatively, the resistance wire 301 includes a plurality of first straight line segments arranged in parallel and at intervals, a second straight line segment is connected between two end points of two adjacent first straight line segments located on opposite sides, and each of the second straight line segments is arranged in parallel; Alternatively, the resistance wire 301 includes a plurality of first arc segments which are arranged in parallel and at intervals, a second arc segment is connected between two end points of two adjacent first arc segments located on opposite sides, and each of the second arc segments is arranged in parallel.

[0077] For example, Fig.10As shown, the first structure of the resistance wire 301 is: the resistance wire 301 is in a broken line shape, and the resistance wire 301 includes a plurality of parallel first straight line segments and a plurality of parallel second straight line segments, and the first straight line segments are perpendicular to the second straight line segments, two adjacent first straight line segments are located between two endpoints on the same side to connect the second straight line segments, and two adjacent second straight line segments are staggered, and the second straight line segments on the same side of the first straight line segments are located on the same straight line, so that the first straight line segments and the second straight line segments are alternately connected in sequence to form a "J" shape.

[0078] For example, Fig.11 As shown, the second structure of the resistance wire 301 is: the resistance wire 301 is in a broken line shape, and the resistance wire 301 includes a plurality of parallel first straight line segments and a plurality of parallel second straight line segments, and the first straight line segments and the second straight line segments are arranged at an acute angle, and two adjacent first straight line segments are connected to the second straight line segment between two endpoints on opposite sides, and the first straight line segments and the second straight line segments are alternately connected in sequence to form a V shape.

[0079] For example, Fig.12 As shown, the third structure of the resistance wire 301 is: the resistance wire 301 is arc-shaped, and the resistance wire 301 includes multiple parallel first arc segments and multiple parallel second arc segments, and the bending directions of the first arc segments and the second arc segments are opposite and connected to form a wave shape.

[0080] In this example, by designing three different shapes of the resistance wire 301 , the resistance wire 301 can be densely spread over the bottom wall of the object carrier 20 , thereby keeping the heating temperature of each position of the substrate 11 consistent.

[0081] It should be noted that, by using the device for preparing an organic light-emitting device provided by the present application, by controlling the evaporation time at different positions of the substrate 11, such as a longer evaporation time near the center position and a shorter evaporation time near the surrounding edge positions, it is also possible to form a light-emitting layer with a decreasing thickness from the center position to the surrounding edge positions on the substrate 11. Alternatively, by controlling the evaporation rate of the guest material at different positions on the substrate 11, such as a faster evaporation rate of the guest material near the center position and a slower evaporation rate of the guest material near the surrounding edge positions, it is also possible to form a light-emitting layer with a decreasing doping concentration from the center position to the surrounding edge positions on the substrate 11.

[0082] On the other hand, Fig.13 As shown, a display panel 100 is provided, comprising the organic light-emitting device 10 described in any embodiment of the present application, or comprising the organic light-emitting device preparation device or the obtained organic light-emitting device 10 described in any embodiment of the present application.

[0083] The specific technical features and beneficial effects of the above-mentioned display panel 100 are the same as the technical features and beneficial effects of the organic light-emitting device 10 provided in the above-mentioned embodiment of the present disclosure, and will not be repeated here. On the other hand, Fig.14 As shown, a display device 1000 is provided, comprising the display panel 100 described in any embodiment of the present application.

[0084] The display device 1000 includes the display panel 100 as described above, and may also include other components, for example, may include a circuit for providing an electrical signal to the display panel 100 to drive the display panel 100 to emit light, which circuit may be called a control circuit, and may include a circuit board and / or an IC (Integrate Circuit) electrically connected to the display panel 100. In some embodiments, the display device 1000 may be a lighting device, in which case the display device 1000 is used as a light source to achieve a lighting function. For example, the display device 1000 may be a backlight module in a liquid crystal display device 1000, a lamp for internal or external lighting, or various signal lamps. In other embodiments, the display device 1000 may be a display substrate for realizing the function of displaying an image (i.e., a picture). The display device 1000 may include a display or a product including a display. Among them, the display may be a flat panel display (Flat Panel Display, FPD), a micro display, etc. If divided according to whether the user can see the back of the display, the display may be a transparent display or an opaque display. If divided according to whether the display can be bent or curled, the display may be a flexible display or a normal display (which may be called a rigid display). Examples of products incorporating a display may include: computer monitors, televisions, billboards, laser printers with display capabilities, telephones, cell phones, personal digital assistants (PDAs), laptop computers, digital cameras, camcorders, viewfinders, vehicles, large-area walls, theater screens or stadium signs, etc.

[0085] The technical features and beneficial effects of the above-mentioned display device 1000 are the same as the technical features and beneficial effects of the display panel 100 provided in the above-mentioned embodiment of the present disclosure, and are not described in detail here.

[0086] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other to form a technical solution.

Claims

1. An organic light-emitting device, characterized in that: include: A substrate, wherein a light-emitting layer is disposed on the substrate, wherein the doping concentration of the light-emitting layer decreases from the center position to the peripheral edge positions, wherein the light-emitting layer comprises a host material and a guest material, and the doping concentration is the mass proportion of the guest material in the host material; Or / and, the thickness of the light-emitting layer decreases from the center to the edges thereof, and the thickness is the thickness of the light-emitting layer in a direction perpendicular to the plane where the substrate is located.

2. The organic light-emitting device according to claim 1, characterized in that: The decreasing rate of the doping concentration from the center position to the peripheral edge position of the light-emitting layer decreases successively.

3. The organic light-emitting device according to claim 1, characterized in that: The doping concentration at the center of the light-emitting layer is 1.5% to 2.5%, and the doping concentration at the edges of the light-emitting layer is 0.5% to 1.5%.

4. The organic light-emitting device according to claim 1, characterized in that: The thickness of the light-emitting layer at the center is 230Å~280Å, and the thickness of the light-emitting layer at the edges is 180Å~220Å.

5. The organic light-emitting device according to any one of claims 1 to 4, characterized in that: The organic light emitting device further comprises a pixel definition layer disposed on the substrate, the pixel definition layer comprises a plurality of opening areas disposed at intervals, the light emitting layer is disposed in each of the opening areas, and the light emitting layer in at least some of the opening areas is a blue light emitting layer.

6. The organic light emitting device according to claim 5, characterized in that: An anode is also arranged between the light-emitting layer and the substrate. The anode is arranged in one-to-one correspondence with the light-emitting layer in the opening area, and a heat-conducting layer is arranged on a side of the anode corresponding to the blue light-emitting layer close to the substrate.

7. The organic light emitting device according to claim 6, characterized in that: The projection of the heat-conducting layer on the substrate at least covers the projection of the anode corresponding to the blue light-emitting layer on the substrate.

8. A device for preparing an organic light-emitting device, characterized in that: The preparation device is used to obtain the organic light-emitting device according to any one of claims 1 to 7, and the preparation device comprises: a carrier, wherein the carrier has a carrier cavity, and the carrier cavity is used to place the material to be evaporated; The object carrier has a bottom wall and a top wall which are arranged opposite to each other, and a heating source is arranged outside the bottom wall of the object carrier, and the heating source is used to heat the material to be evaporated; A plurality of nozzles connected to the carrier cavity are arranged on the top wall of the carrier, and the nozzles are arranged at intervals from the center position of the top wall of the carrier to the edges of the four sides. The nozzles are used to spray the material to be evaporated after being heated by the heating source toward the organic light-emitting device to evaporate and form the light-emitting layer.

9. The device for preparing an organic light-emitting device according to claim 8, characterized in that: The apertures of the plurality of nozzles located from the center of the top wall of the object carrier to the peripheral edges thereof decrease in sequence.

10. The device for preparing an organic light-emitting device according to claim 8, characterized in that: There are multiple heating sources, and the multiple heating sources are spaced apart from the center position of the bottom wall to the surrounding edge positions of the object carrier, and the heating powers of the multiple heating sources located from the center position of the bottom wall to the surrounding edge positions of the object carrier are the same.

11. The device for preparing an organic light-emitting device according to claim 8, characterized in that: The heating source comprises a resistance wire, the resistance wire is in a zigzag shape or an arc shape, and the resistance wire covers the bottom wall of the object carrier.

12. The device for preparing an organic light-emitting device according to claim 11, characterized in that: The resistance wire comprises a plurality of first straight line segments which are arranged in parallel and at intervals, a second straight line segment is connected between two end points of two adjacent first straight line segments located on the same side, and two adjacent second straight line segments are arranged staggered; Alternatively, the resistance wire comprises a plurality of first straight line segments which are arranged in parallel and at intervals, a second straight line segment is connected between two end points of two adjacent first straight line segments located on opposite sides, and each of the second straight line segments is arranged in parallel; Alternatively, the resistance wire comprises a plurality of first arc segments which are arranged in parallel and at intervals, a second arc segment is connected between two end points of two adjacent first arc segments located on opposite sides, and each of the second arc segments is arranged in parallel.

13. A display panel, characterized in that: An organic light-emitting device comprising any one of claims 1 to 7, or an organic light-emitting device preparation device or the obtained organic light-emitting device comprising any one of claims 8 to 12.

14. A display device, characterized in that: Comprising the display panel as claimed in claim 13.

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