Light-emitting device and display substrate

Abstract

The present application provides a light-emitting device and a display substrate, wherein the light-emitting device includes an anode, a cathode, and a light-emitting functional layer located between the anode and the cathode. The light-emitting functional layer includes a light-emitting layer, a hole transport layer, and a hole injection composite layer, wherein the hole transport layer is located between the light-emitting layer and the anode. The hole injection composite layer is located between the hole transport layer and the anode, and includes a plurality of hole injection layers and a plurality of spacer layers, wherein the hole injection layers and the spacer layers are alternately stacked, and the lateral resistance value of the spacer layer is greater than the lateral resistance value of the hole injection layer. By providing the above-mentioned hole injection composite layer, the current crosstalk problem between adjacent light-emitting devices can be alleviated, thereby improving the display effect of the display substrate.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a light-emitting device and a display substrate having the light-emitting device. Background Art

[0002] Organic Light-Emitting Diode (OLED) has many advantages such as simple preparation process, low cost, low power consumption, high brightness, wide viewing angle, high contrast and flexible display, and is therefore widely used in various electronic display products.

[0003] However, due to the large difference in turn-on voltage between light-emitting devices of different colors (i.e., the main structure of the sub-pixel) at low grayscale, it is easy to cause lateral current to appear between light-emitting devices of different colors. This lateral leakage can cause the light-emitting device with low turn-on voltage to appear to be straying, which degrades the display quality of electronic display products and reduces the user experience. Summary of the Invention

[0004] A first aspect of the present application provides a light-emitting device comprising an anode, a cathode, and a light-emitting functional layer positioned between the anode and the cathode. The light-emitting functional layer comprises a light-emitting layer, a hole transport layer, and a hole injection composite layer, wherein the hole transport layer is positioned between the light-emitting layer and the anode. The hole injection composite layer is positioned between the hole transport layer and the anode and comprises a plurality of hole injection layers and a plurality of spacer layers. The hole injection layers and the spacer layers are alternately stacked, and the lateral resistance of the spacer layers is greater than that of the hole injection layers.

[0005] In the above solution, the spacer layer can increase the amount of holes entering the light-emitting layer through the hole transport layer, thereby also reducing the lateral leakage of the light-emitting device.

[0006] In combination with the first aspect, in some embodiments, in a direction from the anode to the hole transport layer, the first film layer and the last film layer of the hole injection composite layer are both hole injection layers.

[0007] In the above solution, the hole injection layer is arranged close to the anode and the hole transport layer, which simplifies the hole transition process and improves the efficiency of hole transfer, thereby improving the performance of the light-emitting device.

[0008] In combination with the first aspect, in some embodiments, the spacer layer and the hole transport layer are made of the same material.

[0009] In the above solution, there is no need to research, develop and design the materials for preparing the spacer layer, which improves production efficiency and saves production costs.

[0010] In combination with the first aspect, in some embodiments, the hole injection layer is doped with a P-type material. Furthermore, the smaller the distance from the light-emitting layer, the lower the doping concentration of the P-type material in the hole injection layer.

[0011] In the above scheme, by adjusting the doping concentration of the P-type material in different hole injection layers, not only the service life of the light-emitting device is improved by increasing the strength of the interface contact between the first hole injection layer of the hole injection composite layer facing the anode and the anode, but also the lateral leakage of the light-emitting device is effectively improved without affecting the performance of the light-emitting device.

[0012] In combination with the first aspect, in some embodiments, the concentration of the P-type material doped in the hole injection layer is 0.5% to 2%.

[0013] In the above solution, the lateral leakage of the light-emitting device is improved without affecting the performance of the device product, and the applicability of the light-emitting device is increased.

[0014] In combination with the first aspect, in some embodiments, the thickness of the hole injection composite layer in the direction perpendicular to the surface where the anode is located is

[0015] In combination with the first aspect, in some embodiments, the thickness of the hole injection layer in the direction perpendicular to the surface where the anode is located is For example, further, the total thickness of all hole injection layers in the hole injection composite layer is not less than

[0016] In the above scheme, the lateral leakage of the light-emitting device is improved while minimizing the impact on the performance of the light-emitting device, and the number and thickness of the hole injection layer can be set according to the actual needs of the light-emitting device, thereby improving the applicability of the light-emitting device.

[0017] In combination with the first aspect, in some embodiments, the thickness of the spacer layer in the direction perpendicular to the surface where the anode is located is

[0018] In the above scheme, the thickness of the spacer layer is set from the aspects of the spacer layer manufacturing process and the effect of suppressing the increase of lateral current, which facilitates the preparation of the spacer layer, improves the production efficiency of the light-emitting device, and thus increases the production cost.

[0019] The second aspect of the present application provides a display substrate, which includes an array substrate and a display function layer located on the array substrate, the display function layer includes a plurality of light-emitting devices arranged in an array, wherein at least one of the plurality of light-emitting devices is any one of the light-emitting devices provided in the first aspect above.

[0020] In the above solution, the lateral leakage of the light-emitting device in the display substrate is improved, the display effect of the display substrate is improved, and the service life of the display substrate is also increased, thereby improving user satisfaction.

[0021] In combination with the second aspect, in some embodiments, the plurality of light-emitting devices are all configured to be any one of the light-emitting devices provided in the first aspect.

[0022] In combination with the second aspect, in other embodiments, multiple light-emitting devices are classified into light-emitting devices that respectively emit light of multiple wavelengths, and the light-emitting device that emits light of the shortest wavelength is set to any one of the light-emitting devices provided in the first aspect of the embodiment of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments.

[0024] Figure 1 Schematic diagram of the structure of a light-emitting device according to an embodiment of the present application.

[0025] Figure 2 yes Figure 1 A partial cross-sectional view of the light emitting device shown. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0027] In the display substrate, the turn-on voltages of OLEDs emitting different colors (such as red, green, and blue) at low grayscales vary significantly, which can easily lead to lateral leakage current. This can cause light-stealing between light-emitting devices of different colors at low grayscales, seriously affecting the display effect of the entire display substrate.

[0028] The embodiments of the present application provide a light-emitting device and a display substrate including the light-emitting device, which can at least improve the phenomenon that light-emitting devices of different colors appear to be hidden in the display substrate during the low gray stage.

[0029] The embodiment of the present application provides a light emitting device, such as Figure 1 and Figure 2As shown, the light-emitting device includes an anode 12, a cathode 18, and a light-emitting functional layer located between the anode 12 and the cathode 18. The light-emitting functional layer includes a light-emitting layer 15, a hole transport layer 14, and a hole injection composite layer 13. The hole transport layer 14 is located between the light-emitting layer 15 and the anode 12. The hole injection composite layer 13 is located between the hole transport layer 14 and the anode 12 and includes multiple hole injection layers 131 and multiple spacer layers 132. The hole injection layers 131 and the spacer layers 132 are alternately stacked. The lateral resistance of the spacer layers 132 is greater than the lateral resistance of the hole injection layers 131. This design reduces the amount of holes lost on the side of the hole injection composite layer 13 facing the anode 12, that is, at a position farther away from the hole transport layer 14. This is equivalent to causing more holes to gather in the area close to the hole transport layer 14. In this way, the amount of holes entering the light-emitting layer 15 through the hole transport layer 14 can be increased, which is equivalent to slowing down the lateral leakage of the light-emitting device. Therefore, the lateral leakage of the light-emitting device is improved without basically affecting the performance of the light-emitting device.

[0030] Specifically, in the above Figure 1 and Figure 2 In the light-emitting device of the illustrated embodiment, a hole injection recombination layer 13 is used to lower the potential barrier between the anode 12 and the hole transport layer 14, enabling holes injected from the anode 12 to be transported to the hole transport layer 14. In the hole injection recombination layer 13, holes no longer directly pass through a single hole injection layer as in the prior embodiment, but instead sequentially pass through an overlapping, thinned hole injection layer 131 and a spacer layer 132 before ultimately reaching the hole transport layer 14. During this process, the holes pass through the thinned hole injection layer 131, improving the lateral leakage of the light-emitting device. Furthermore, the lateral resistance of the spacer layer 132 is greater than that of the hole injection layer 131, further preventing lateral current transmission and transferring holes transferred from the first hole injection layer 131 connected to the anode 12 to the next hole injection layer 131, the second hole injection layer 131. This improves the lateral leakage of the light-emitting device without substantially affecting the performance of the light-emitting device.

[0031] It should be understood that, under the premise that the transverse resistance of the spacer layer 132 is greater than the transverse resistance of the hole injection layer 131, if the thickness of the spacer layer 132 needs to be less than or equal to the thickness of the hole injection layer 131, then when selecting the material for the spacer layer 132, it is necessary to consider that the transverse conductivity of the material for the spacer layer 132 is less than or equal to the transverse conductivity of the material for the hole injection layer 131. Conversely, if the transverse conductivity of the material for the spacer layer 132 is determined to be greater than or equal to the transverse conductivity of the material for the hole injection layer 131, it is necessary to consider that the thickness of the spacer layer 132 is greater than the thickness of the hole injection layer 131. The spacer layer 132 and the hole injection layer 131 can be prepared based on the above rules.

[0032] For example, Figure 1 The anode 12 of the light-emitting device is provided on a substrate 11. The light-emitting functional layer further includes a hole blocking layer 16 located between the light-emitting layer 15 and the cathode 18, an electron injection layer located between the hole blocking layer 16 and the cathode 18, an electron transport layer, and one or more other organic material layers. The organic material layer may be a single-layer structure or a multilayer structure of two or more organic material layers in series. It should be understood that the above scheme is merely exemplary, and the light-emitting layer 15 of the light-emitting device is not limited to the above structure and may be redesigned according to specific needs. For example, to improve the luminous efficiency, an electron blocking layer may be added between the anode 12 and the light-emitting layer 15, or a hole blocking layer 16 may be added between the cathode 18 and the light-emitting layer 15, or an electron input layer 17 may be added between the cathode 18 and the light-emitting layer 15, or the above schemes may be combined.

[0033] In some embodiments, in the direction from the anode 12 to the hole transport layer 14, the first film layer and the last film layer of the hole injection composite layer 13 are both hole injection layers 131. It is understandable that the end of the hole injection composite layer 13 away from the anode 12 is connected to the hole transport layer 14, and the hole injection composite layer 13 or the hole injection layer 131 is required between the anode 12 and the hole transport layer 14 as a barrier step so that the holes injected by the anode 12 are eventually transferred to the hole transport layer 14. It can be seen that the potential barrier of the spacer layer 132 is greater than the potential barrier of the hole injection layer 131, and the potential barrier of the spacer layer 132 is also less than or equal to the potential barrier of the hole transport layer 14. The structural solution in which the first film layer and the last film layer in the hole injection composite layer 13 are both hole injection layers 131 is to allow holes to traverse the least different film layers and then gather in the hole transport layer 14, which can simplify the hole transition step, optimize the film structure of the light-emitting device, and improve the efficiency of hole transfer, thereby improving the performance of the light-emitting device.

[0034] In some embodiments, the spacer layer 132 is made of the same material as the hole transport layer 14. As can be seen from this solution, when manufacturing the light-emitting device provided in the above embodiment, there is no need to further research and design the material for preparing the spacer layer 132, thereby improving production efficiency and saving production costs. It is understood that when selecting the material for preparing the hole transport layer 14, factors such as work function, energy level, coupling efficiency, evaporation uniformity, and evaporation temperature can be considered. Generally speaking, any one of macromolecular organic compounds such as triarylamines, carbazoles, organic amines, butadiene compounds, and aromatic polyamine compounds can be selected.

[0035] It should be understood that the above embodiment merely provides an exemplary solution for selecting materials for preparing the spacer layer 132, and the actual process is not limited thereto. The material of the hole transport layer 14 may be processed according to the actual requirements of the light-emitting device to obtain a new material with hole transport properties to prepare the spacer layer 132. For example, the new material may be obtained by doping to prepare the spacer layer 132. Specifically, when the thickness of the spacer layer 132 can be less than or equal to the thickness of the hole injection layer 131, doping can be used to increase the resistivity of the material used to prepare the spacer layer 132, thereby increasing the lateral resistance of the spacer layer 132.

[0036] In some embodiments, the hole injection layer is doped with a P-type material. Furthermore, the smaller the distance from the light-emitting layer, the lower the doping concentration of the P-type material in the hole injection layer. By adjusting the doping concentration of the P-type material in different hole injection layers 131, on the one hand, the strength of the interface contact between the first hole injection layer 131 of the hole injection composite layer 13 and the anode 12 is improved, so that the anode 12 (inorganic layer) and the hole injection layer 131 (organic layer) located in the first layer can achieve a stable ohmic contact to ensure that holes are effectively injected, thereby improving the service life of the light-emitting device; on the other hand, in the direction from the anode 12 to the hole transport layer 14, the doping concentration of the P-type material in the hole injection layer 131 in the hole injection composite layer 13 is gradually reduced, which effectively improves the lateral leakage of the light-emitting device without affecting the performance of the light-emitting device.

[0037] It should be understood that the doping concentration of the P-type material is inversely proportional to the lateral resistance of the film layer, that is, the higher the doping concentration, the lower the lateral resistance, and the greater the lateral leakage of the film layer. In the above embodiment, based on considerations of the performance of the light-emitting device, the doping concentration of the P-type material in the first hole injection layer 131 contacting the anode 12 is maximized. This improves the strength of the interface contact between the first hole injection layer 131 and the anode 12, reduces the risk of interface separation between the light-emitting functional layer and the anode, and thus improves the service life of the light-emitting device. At the same time, in the direction from the anode 12 to the hole transport layer 14, the doping concentration of the P-type material in the hole injection layer 131 in the hole injection composite layer 13 gradually decreases. Without affecting the total amount of P-type material doping, the lateral resistance of the hole injection layer 131 is gradually increased. The greater the lateral resistance of the hole injection layer 131, the smaller the lateral current in each hole injection layer 131 is, in combination with the lateral current blocking effect of the spacer layer 132. Therefore, without affecting the performance of the light-emitting device, the lateral leakage of the light-emitting device is effectively improved.

[0038] In some embodiments, the concentration of the P-type material doped in the hole injection layer 131 is 0.5% to 2%, for example, further 0.8%, 1%, 1.2%, 1.5%, 1.8%, etc. Specifically, based on the fact that holes need to pass through multiple hole injection layers 131 to reach the hole transport layer 14 from the anode 12, and the hole injection layer 131 has become thinner, the lateral leakage of the light-emitting device is improved. In addition, the P-type material with the same, similar or different doping concentrations in each hole injection layer 131 is made so that the concentration of the P-type material meets the requirements of the light-emitting device, while not affecting the performance of the light-emitting device, and also improving the lateral leakage of the light-emitting device. It should be understood that the concentration of the P-type material doped in each hole injection layer 131 can be designed according to the performance requirements of the light-emitting device and the requirements for the current size of the lateral leakage, thereby increasing the applicability of the light-emitting device.

[0039] In some embodiments, the thickness of the hole injection composite layer 13 in the direction perpendicular to the surface of the anode is For example, further Taking into account factors such as the structural dimensions of the light-emitting device and the requirements of the packaging process, the thickness of the hole injection composite layer 13 is limited. This allows the light-emitting device having this structure to have improved lateral leakage while maintaining satisfactory performance. This eliminates the need for major improvements to the processing technology of the light-emitting device, thereby improving production efficiency and saving production costs.

[0040] In some embodiments, the thickness of the hole injection layer 131 in the direction perpendicular to the surface of the anode is For example, further etc.; further, the total thickness of all hole injection layers 131 in the hole injection composite layer 13 is not less than For example, further wait.

[0041] It should be understood that the specific number of layers of the hole injection layer 131 in the hole injection composite layer 13 is not limited. By making the hole injection composite layer 13 into a multi-layer structure, the lateral leakage of the light-emitting device is improved while minimizing the impact on the performance of the light-emitting device. In this way, by limiting the total thickness of the hole injection layer 131 in the hole injection composite layer 13, the lateral leakage of the light-emitting device can be improved without affecting the performance of the light-emitting device. It should be noted that in actual processes, the number of layers and thickness of the hole injection layer 131 can be set according to the actual requirements of the light-emitting device to improve the applicability of the light-emitting device.

[0042] In some embodiments, the thickness of the spacer layer 132 in the direction perpendicular to the surface of the anode 12 is The thickness of the spacer layer 132 is set based on the manufacturing process of the spacer layer 132 and its effect of suppressing the increase of the lateral current. The spacer layer 132 within the above-mentioned thickness range can reduce the lateral leakage without affecting or having relatively little impact on the performance of the light-emitting device. At the same time, it can also make the thickness of the hole injection composite layer 13 relatively low, so as to reduce the impact on the overall module design of the light-emitting device, facilitate the preparation of the spacer layer 132, improve the production efficiency of the light-emitting device, and increase the production cost.

[0043] In some embodiments, the hole injection composite layer 13 is formed on the anode 12 by evaporation. Specifically, during the evaporation process, the angle of the limiting plate is adjusted so that the spray range of the HT material nozzle and the spray range of the P-doped material nozzle overlap to a certain extent. During evaporation, the two nozzles scan back and forth from left to right relative to the anode, and the number of scans determines the number of overlapping layers of the hole injection layer 131 and the spacer layer 132 in the hole injection composite layer 13. It should be understood that the above is only one preparation method for the hole injection composite layer 13 and is not limited to the above method in actual production.

[0044] In this embodiment, the hole transport material (HT) and P-type dopant material used in the light-emitting device sample are both materials well known in the industry, wherein the hole injection layer (HI) is prepared by doping the hole transport material (HT) and the P-type dopant material.

[0045] The structure of the hole-injection recombination layer and the doping ratio of the P-type dopant material have different effects on the luminescent properties of the light-emitting device. This is illustrated below using different light-emitting device samples. In these light-emitting device samples, except for the structure of the hole-injection recombination layer or HI layer, the configuration of the other layer structures in the light-emitting device is the same. The structural configuration of the hole-injection recombination layer or HI layer in these light-emitting device samples can be found in Table 1 below:

[0046] Table 1 shows the thickness parameters of the hole injection composite layer or HI layer structure in different light-emitting device samples

[0047]

[0048]

[0049] The lateral resistance of the hole injection composite layer in the sample and the HI film layer in the comparative example were tested. The above-mentioned organic film layer was prepared on an ITO conductive film layer with a comb-like structure, and an electrode with a material ratio of Ag:Mg=9:1 was prepared above the HI film layer. The JV curve was tested by a current source to calculate the resistance of the film. No more details will be given. The specific test data is shown in Table 2 below.

[0050] Table 2 shows the lateral resistance values ​​of the hole injection composite layer or HI film layer in different light-emitting device samples

[0051] Light-emitting devices Transverse resistance (Ω / □) Sample 1 4.2E+11 Sample 2 8.6E+11 Sample 3 2.1E+12 Sample 4 4.8E+11 Sample 5 6.7E+11 Sample 6 6.6E+11 Sample 7 7.3E+11 Sample 8 8.6E+11 Sample 9 9.8E+11 Sample 10 9.7E+11 Sample 11 1.8E+12 Sample 12 2.1E+12 Sample 13 1.0E+12 Sample 14 1.8E+12 Sample 15 2.0E+12 Sample 16 2.2E+12 Sample 17 1.5E+11 Sample 18 6.3E+11 Sample 19 8.9E+11

[0052] Combining the analysis of Tables 1 and 2, and comparing Sample 2 and Sample 17, it can be seen that, when the P-type doping concentration of the light-emitting device is the same and the thickness is similar, the lateral resistance value of Sample 2 is much greater than that of Sample 17. This is because the light-emitting device of Sample 2 uses a hole injection composite layer between the hole transport layer and the anode, and the hole injection composite layer includes two hole injection layers and a spacer layer located therebetween, while the light-emitting device of Sample 17 uses a single hole injection layer or a composite layer structure between the hole transport layer and the anode.

[0053] By comparing Samples 1, 2 and 3, it can be seen that the lateral resistance value of the light-emitting device using a hole injection composite layer structure decreases as the P-type doping concentration in the HI film layer decreases when other parameters remain unchanged; by comparing Samples 4 and 5, it can be seen that when the P-type doping concentration of the hole injection composite layer remains unchanged, the thickness of the HI film layer decreases and the total thickness of the hole injection composite layer decreases, the lateral resistance value of the light-emitting device increases; from Samples 6, 7, 8 and 9, it can be seen that the lateral resistance value of the light-emitting device increases when the P-type doping concentration of the hole injection composite layer increases and the thickness of the HI film layer increases while the total thickness of the hole injection composite layer increases, or when the P-type doping concentration of the hole injection composite layer remains unchanged and the thickness of the HI film layer increases while the total thickness of the hole injection composite layer increases.

[0054] Comparing Sample 10 and Sample 7, it can be seen that, with the total thickness of the hole injection composite layer unchanged, increasing the number of spacer layers and HI film layers can increase the lateral resistance of the light-emitting device. Furthermore, Samples 10, 11, 12, 13, 14, 15, and 16 show that, in the case of multiple layers, the lateral resistance of the light-emitting device decreases as the P-type dopant concentration in the HI layer decreases. However, Samples 17, 18, and 19 show that the lateral resistance of the light-emitting device containing only the HI film layer decreases as the P-type dopant concentration in the HI film layer increases.

[0055] In the following examples, only the performance of blue light device samples with different HI layer structures and the spectral proportions of green light and red light relative to the blue light intensity are given. The specific data are shown in Table 3 below:

[0056] Table 3 Blue light device related performance

[0057]

[0058]

[0059] Combining the analysis of Table 1 and Table 3, it can be seen from the comparison of Sample 2 and Sample 17 that the green light intensity ratio and the red light intensity ratio of Sample 2 are smaller than those of Sample 17, that is, the color cast phenomenon of Sample 2 is not obvious relative to the color cast phenomenon of Sample 17. It can be seen that a hole injection composite layer is arranged between the hole transport layer and the anode of the light-emitting device, and the hole injection composite layer includes a structure of two hole injection layers and a spacer layer located therebetween, which can improve the color cast phenomenon of the light-emitting device.

[0060] By comparing Sample 1, Sample 2 and Sample 3, it can be seen that the lateral resistance value of the light-emitting device using a hole injection composite layer structure can more effectively reduce the color cast of the light-emitting device as the P-type doping concentration in the HI film layer decreases when other parameters remain unchanged; by comparing Sample 4 and Sample 5, it can be seen that when the P-type doping concentration of the hole injection composite layer remains unchanged, the thickness of the HI film layer becomes smaller and the total thickness of the hole injection composite layer becomes smaller, the color cast of the light-emitting device can be effectively improved, and the impact on the life of the light-emitting device is not very large; by comparing Sample 6, Sample 7, Sample 8 and Sample 9, it can be seen that when the P-type doping concentration of the hole injection composite layer increases and the thickness of the HI film layer increases while the total thickness of the hole injection composite layer increases, or when the P-type doping concentration of the hole injection composite layer remains unchanged and the thickness of the HI film layer increases while the total thickness of the hole injection composite layer increases, the color cast of the light-emitting device can be effectively improved, and the impact on the life of the light-emitting device is not very large.

[0061] By comparing sample 10 and sample 7, it can be seen that, when the total thickness of the hole injection composite layer remains unchanged, increasing the number of layers of the spacer layer and the HI film layer therein can effectively improve the color cast phenomenon of the light-emitting device without basically affecting the life of the light-emitting device. It can be seen from samples 10, 11, 12, 13, 14, 15 and 16 that, in the case of multiple layers, as the concentration of P-type doping in the HI film layer increases, the color cast phenomenon of the light-emitting device can be more effectively improved. It can be seen from comparing sample 15 and sample 16 that only by changing the concentration of P-type doping in the HT film layer to improve the color cast phenomenon of the light-emitting device will have a negative impact on the service life of the light-emitting device. By comparing sample 13 and sample 14, it can be seen that by changing the thickness of the spacer layer and the hole injection layer in the hole injection composite layer and the concentration of P-type doping, the color cast problem of the light-emitting device can be improved, while reducing the impact on the service life of the light-emitting device. It can be seen from Samples 17, 18 and 19 that for light-emitting devices containing only HI film layers, as the P-type doping concentration increases, the color cast phenomenon of the light-emitting device can be effectively improved, but the life of the light-emitting device is greatly reduced.

[0062] The present application also provides a display substrate. The display substrate includes an array substrate and a display function layer located on the array substrate. The display function layer includes a plurality of light-emitting devices arranged in an array, wherein at least one of the plurality of light-emitting devices is configured as any of the light-emitting devices provided in the present application. While improving lateral leakage of the light-emitting devices in the display substrate, the display quality and lifespan of the display substrate are also improved, thereby enhancing user satisfaction.

[0063] In some embodiments, all of the multiple light-emitting devices are set to any one of the light-emitting devices provided in the above embodiments of the present application; or the multiple light-emitting devices are classified into light-emitting devices that respectively emit light of multiple wavelengths, and the light-emitting device that emits light of the shortest wavelength is set to any one of the light-emitting devices provided in the above embodiments of the present application.

[0064] In some embodiments of the present application, all the light-emitting devices in the display substrate are any one of the light-emitting devices provided in the above embodiments of the present application, which effectively improves the display effect of the display substrate, increases the life of the display substrate, and thereby improves user satisfaction. The display substrate may include only a plurality of light-emitting devices that emit light of one color, or may include a plurality of light-emitting devices that emit light of different colors (equivalent to emitting light of different wavelengths).

[0065] In other embodiments of the present application, the display substrate includes a plurality of light-emitting devices that emit light of different colors, and the problem of lateral leakage has a relatively large impact on the display effect of the display substrate. This is because light-emitting devices of different colors emit light of different colors, and the corresponding light-emitting device with a smaller wavelength of light requires a larger turn-on voltage in the low-gray stage. At this time, the lateral leakage of the light-emitting device with the smallest wavelength of light emitted will flow through the common layer (such as the hole injection layer HIL) between light-emitting devices of different colors to the light-emitting device with a lower turn-on voltage (i.e., the emitted light wavelength is larger) (i.e., the lateral leakage current between different light-emitting devices), which will cause the light-emitting device with a lower turn-on voltage to be lit. Therefore, the light-emitting device with the smallest wavelength of light emission can be any of the light-emitting devices provided in the above embodiments of the present application, which not only improves the display effect of the display substrate but also reduces the cost of the display substrate.

[0066] It should be understood that, depending on the cost and quality requirements of the display substrate, all, part or any one of the light-emitting devices in the display substrate may adopt any one of the light-emitting devices provided in the above embodiments of the present application.

[0067] The present invention also provides a display device. The display device provided in the present invention may include the display substrate provided in the present invention. The display device provided in the present invention may be, but is not limited to, any of the following electronic display products: a television, a digital camera, a mobile phone, a watch, a tablet computer, a laptop computer, or a navigation system.

[0068] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A light emitting device, characterized in that: The invention comprises an anode, a cathode and a light-emitting functional layer located between the anode and the cathode, wherein the light-emitting functional layer comprises: a luminescent layer; a hole transport layer located between the light-emitting layer and the anode; and A hole injection composite layer, located between the hole transport layer and the anode, and comprising a plurality of hole injection layers and a plurality of spacer layers, wherein the hole injection layers and the spacer layers are alternately stacked; Wherein, the transverse resistance value of the spacer layer is greater than the transverse resistance value of the hole injection layer.

2. The light emitting device according to claim 1, wherein In the direction from the anode to the hole transport layer, the first film layer and the last film layer of the hole injection composite layer are both the hole injection layers.

3. The light emitting device according to claim 1, wherein The spacer layer and the hole transport layer are made of the same material.

4. The light emitting device according to any one of claims 1 to 3, characterized in that: The hole injection layer is doped with P-type material.

5. The light emitting device according to claim 4, characterized in that The smaller the distance between the hole injection layer and the light emitting layer is, the lower the doping concentration of the P-type material in the hole injection layer is.

6. The light emitting device according to claim 5, characterized in that The concentration of the P-type material doped in the hole injection layer is 0.5% to 2%.

7. The light emitting device according to any one of claims 1 to 3, characterized in that: In the direction perpendicular to the surface of the anode, the thickness of the hole injection composite layer is 8. The light emitting device according to claim 7, characterized in that In the direction perpendicular to the surface of the anode, the thickness of the hole injection layer is 9. The light emitting device according to claim 8, characterized in that The sum of the thicknesses of all the hole injection layers in the hole injection composite layer is not less than 10. The light emitting device according to claim 7, characterized in that In the direction perpendicular to the surface of the anode, the thickness of the spacer layer is 11. A display substrate, characterized in that: include: array substrate; as well as A display function layer, located on the array substrate and comprising a plurality of light-emitting devices arranged in an array; Wherein, at least one of the plurality of light-emitting devices is the light-emitting device according to any one of claims 1 to 10.

12. The display substrate according to claim 11, wherein: The plurality of light-emitting devices are all configured as light-emitting devices according to any one of claims 1 to 10; or The plurality of light emitting devices are classified into light emitting devices that respectively emit light of multiple wavelengths, and the light emitting device that emits light of the shortest wavelength is set to be the light emitting device according to any one of claims 1 to 10.

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