Display panel

Abstract

The embodiment of the present application provides a display panel. The display panel comprises a light-emitting functional layer, the light-emitting functional layer comprises a plurality of light-emitting layers and a charge generation layer between the light-emitting layers, the charge generation layer is doped with first metal ions and second metal ions, and the two different ions are arranged with different doping concentrations and doping characteristics in different regions, so that the use stability and the service life of the light-emitting functional layer are further improved by doping different ions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display panel manufacturing, in particular to a display panel. BACKGROUND

[0002] With the continuous upgrading of electronic products, people have put forward higher requirements on the quality and performance of display panels to enhance the use experience.

[0003] Organic light-emitting diode (OLED) devices have the advantages of lightness, wide viewing angle, high luminous efficiency, etc. compared with traditional liquid crystal display (LCD), and are widely used in various fields. In order to further improve the light-emitting performance of OLED devices, the light-emitting layer in the light-emitting device layer is usually set as a multi-layer in the prior art, and functional ions are added in the light-emitting device layer, so as to improve the light-emitting intensity or light-emitting effect of the display panel by means of the multi-layer stacked light-emitting layer and the functional ions which can improve the charge movement. However, when the light-emitting layer is doped with ions, the improvement of the light-emitting effect and performance of the light-emitting layer after doping is not ideal, and the light-emitting effect and use stability of the light-emitting device layer cannot be ensured.

[0004] In summary, the display panel in the prior art has the problem that the improvement effect of the performance of the light-emitting device layer is not ideal when the multi-layer stacked light-emitting layer is set and the light-emitting device layer is doped with ions, and it cannot meet the demand of people for high-performance display panels. SUMMARY

[0005] The display panel and display device provided by the embodiments of the present application can effectively improve the problem that the performance and stability of the light-emitting device layer are not ideal when the light-emitting layer with a stacked structure is prepared and doped with ions in the prior art display panel.

[0006] To solve the above technical problems, the first aspect of the embodiments of the present application provides a display panel, comprising:

[0007] a light-emitting functional layer, wherein the light-emitting functional layer comprises at least:

[0008] a first light-emitting layer;

[0009] a charge generation layer arranged on one side of the first light-emitting layer; and

[0010] a second light-emitting layer arranged on a side of the charge generation layer away from the first light-emitting layer;

[0011] The charge generation layer further comprises first metal ions and second metal ions, the first metal ions correspond to an atomic mass greater than the second metal ions, and the doping concentration of the first metal ions is greater than the doping concentration of the second metal ions.

[0012] According to an embodiment of the present application, in the thickness direction of the charge generation layer, the doping concentration of the first metal ions on the side close to the first light-emitting layer is less than the doping concentration on the side far from the first light-emitting layer, and the doping concentration of the second metal ions on the side close to the first light-emitting layer is greater than the doping concentration on the side far from the first light-emitting layer.

[0013] According to an embodiment of the present application, the doping concentration of the first metal ions in the charge generation layer is 1% to 15%, and the doping concentration of the second metal ions is 0.05% to 10%.

[0014] According to an embodiment of the present application, the charge generation layer comprises an n-type charge generation layer and a p-type charge generation layer, and the p-type charge generation layer is arranged on the side of the n-type charge generation layer far from the first light-emitting layer.

[0015] The first metal ions and the second metal ions are arranged in the n-type charge generation layer.

[0016] According to an embodiment of the present application, the doping concentration of the first metal ions on the side close to the p-type generation layer is greater than the doping concentration on the side far from the p-type generation layer, and the doping concentration of the second metal ions on the side close to the p-type generation layer is less than the doping concentration on the side far from the p-type generation layer.

[0017] According to an embodiment of the present application, the film layer thickness of the n-type charge generation layer is greater than the film layer thickness of the p-type charge generation layer.

[0018] According to an embodiment of the present application, the p-type charge generation layer has a first Fermi level, and the n-type charge generation layer has a second Fermi level.

[0019] The absolute value of the difference between the first Fermi level and the second Fermi level is 1.5 eV to 2.2 eV.

[0020] According to an embodiment of the present application, in a first direction, the n-type charge generation layer comprises a first region and a second region arranged on the side of the first region, and the first direction is parallel to the surface of the n-type charge generation layer.

[0021] The doping concentration of the first metal ions in the first region is greater than the doping concentration in the second region.

[0022] According to an embodiment of the present application, the light-emitting functional layer further comprises:

[0023] a first hole transport layer (HT) disposed on a side close to the array substrate, and the first light-emitting layer disposed on the first hole transport layer;

[0024] a first electron transport layer (ET) disposed on a side of the first light-emitting layer away from the first hole transport layer;

[0025] a second hole transport layer, the charge generation layer disposed between the first hole transport layer and the first electron transport layer; and

[0026] a second electron transport layer disposed on a side of the second light-emitting layer away from the second hole transport layer.

[0027] According to an embodiment of the present application, in the thickness direction of the charge generation layer, the absolute value of the change rate of the doping concentration of the first metal ions is the same as the absolute value of the change rate of the doping concentration of the second metal ions.

[0028] The present application provides a display panel, which comprises a light-emitting functional layer, the light-emitting functional layer comprising a plurality of light-emitting layers and a charge generation layer between the light-emitting layers, wherein the charge generation layer is doped with first metal ions and second metal ions, and the two different ions are arranged with different doping concentrations and doping properties in different regions, so that the use stability and service life of the light-emitting functional layer are further improved by doping different ions. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the drawings needed in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0030] Figure 1 Part of the film layer structure schematic diagram of the display panel provided in the embodiments of the present application;

[0031] Figure 2 The film layer structure schematic diagram of the charge generation layer provided in the embodiments of the present application;

[0032] Figure 3 The film thickness and Yb+ and Li+ ion corresponding relationship of the n-type charge generation layer provided in the embodiments of the present application;

[0033] Figure 4A preparation process schematic diagram of the n-type charge generation layer film layer provided in the embodiment of the present application;

[0034] Figure 5 A structure schematic diagram of another n-type charge generation layer provided in the embodiment of the present application;

[0035] Figure 6 A film layer and energy level schematic diagram of the light emitting functional layer provided in the embodiment of the present application. DETAILED DESCRIPTION

[0036] In the following detailed description, only certain embodiments of the application have been shown and described, by way of illustration. As those skilled in the art can understand, the embodiments described herein can be modified in various ways without departing from the spirit or scope of the application.

[0037] In the drawings, the thickness of layers, films, plates, regions, etc., can be exaggerated for clarity. Also, unless explicitly described otherwise, the word "comprise" and variations such as "comprising" or "comprises" will be understood to imply the inclusion of a stated element, but not the exclusion of any other element. Further, in the specification, the word "on" means positioned on top of or below the object part, but not necessarily positioned on the upper side of the object part based on the direction of gravity.

[0038] It will be understood that, although the terms "first", "second", etc. can be used herein to describe various components, these components should not be limited by these terms. These components are only used to distinguish one component from another.

[0039] When the display panel is set, the light emitting effect of the light emitting functional layer in the display panel will directly determine the light emitting performance of the display panel. In the prior art, in order to improve the light emitting effect of the display panel, a plurality of light emitting layers are usually stacked to improve the light emitting effect. However, simply stacking a plurality of light emitting layers can easily cause the movement effect of the electric charges in the light emitting functional layer to be not ideal, thereby causing the stability of the light emitting functional layer to be poor and reducing the service life of the panel.

[0040] As shown in FIG. 1, Figure 1 Figure 1 A partial film layer structure schematic diagram of a display panel provided in the embodiment of the present application. Figure 1 Only the main functional layers of the display panel are shown in FIG. 1, and other film layer structures not shown in FIG. 1 can be set according to the structure of a conventional display panel, and the display panels with different structures described above are all within the protection scope of the present application.

[0041] ​Specifically, the display panel comprises an array substrate 100 and a light-emitting functional layer 101. The light-emitting functional layer 101 is arranged on one side of the array substrate 100, and the array substrate 100 is used to drive and control the light-emitting functional layer 101. The array substrate 100 can be a conventional thin film transistor array substrate or other module capable of driving the light-emitting functional layer 101 to work.

[0042] In detail Figure 1 In the process of arranging the array substrate 100 and the corresponding light-emitting functional layer 101, an anode 1001 is arranged on the array substrate 100, and the light-emitting functional layer 101 is electrically connected to the array substrate 100 through the anode 1001.

[0043] Further, in the process of arranging the light-emitting functional layer 101, the light-emitting functional layer 101 provided in the present application comprises a plurality of light-emitting layers, and the light-emitting performance is improved by stacking the light-emitting layers. Specifically, the light-emitting functional layer 101 comprises a first hole transport layer (HTL) 102, a first light-emitting layer 103, a first electron transport layer (ETL) 104, a charge generation layer 20, a second hole transport layer 107, a second light-emitting layer 108, and a second electron transport layer 109. Meanwhile, a cathode 110 is arranged on the light-emitting functional layer 101. In this way, the anode 1001, the light-emitting functional layer 101, and the cathode 110 form a continuous structure, thereby ensuring the normal work of the light-emitting functional layer of the display panel.

[0044] Specifically, in the process of arranging each film layer in the light-emitting functional layer 101, the first hole transport layer 102 is arranged on the side of the anode 1001 away from the array substrate 100, the first light-emitting layer 103 is arranged on the side of the first hole transport layer 102 away from the anode 1001, and the first electron transport layer 104 is arranged on the side of the first light-emitting layer 103 away from the first hole transport layer 102.

[0045] Further, the charge generation layer 20 is arranged on the side of the first electron transport layer 104 away from the array substrate 100, the second hole transport layer 107 is arranged on the side of the charge generation layer 20 away from the array substrate 100, the second light-emitting layer 108 is arranged on the side of the second hole transport layer 107 away from the charge generation layer 20, and the second electron transport layer 109 is arranged on the side of the second light-emitting layer 108 away from the second hole transport layer 107.

[0046] The different film layers are stacked in the above-mentioned stacking order and form the light-emitting functional layer provided in the present application. In the embodiments of the present application, when the first hole transport layer 102, the first light-emitting layer 103, the first electron transport layer 104, the second hole transport layer 107, the second light-emitting layer 108, and the second electron transport layer 109 are arranged, the materials used and the thicknesses of the film layers can be designed according to the corresponding film layers in a conventional display panel. The above-mentioned film layers mainly ensure the normal light-emitting work of the light-emitting functional layer, and the materials and thicknesses of the above-mentioned film layers are not specifically limited here.

[0047] As shown in Figure 2 , Figure 2 is a film layer structure schematic diagram of the charge generation layer provided in the embodiments of the present application. In combination with the structure in Figure 1 , in the embodiments of the present application, when the charge generation layer 20 is arranged, the charge generation layer 20 is doped with the first metal ion 301 and the second metal ion 302, wherein the first metal ion 301 and the second metal ion 302 are metal ions corresponding to different elements. Optionally, the atomic mass of the first metal ion 301 is greater than the atomic mass of the second metal ion 302, and in the thickness direction of the charge generation layer 20, such as in the second direction y, the second direction y is a direction from the array substrate 100 at the bottom of the display panel to the second light-emitting layer 108, and the first direction x is a horizontal direction corresponding to the upper and lower surfaces of the charge generation layer 20.

[0048] In the arrangement of the above-mentioned different doping ions, the doping concentration of the first metal ion 301 near the first light-emitting layer 103 side is less than the doping concentration far from the first light-emitting layer 103 side, and the doping concentration of the second metal ion 302 near the first light-emitting layer 103 side is greater than the doping concentration far from the first light-emitting layer 103 side. In the embodiments of the present application, by adjusting the doping concentration and the doping mode of the two different atomic mass doping ions, the interface defects of the film layer are reduced, and the charge movement in the film layer is balanced, so that the stability and service life of the device are effectively improved while the light-emitting performance is ensured.

[0049] Specifically, refer to the film layer of the charge generation layer in Figure 2 . In the present application, the charge generation layer 20 includes an n-type charge generation layer 105 and a p-type charge generation layer 106. The p-type charge generation layer 106 is arranged on the side of the n-type charge generation layer 105 away from the array substrate 100. In the embodiments of the present application, the above-mentioned first metal ion 301 and the second metal ion 302 are both arranged in the n-type charge generation layer 105. By improving the performance of the n-type charge generation layer 105, the performance of the light-emitting functional layer is improved.

[0050] In the embodiment of the present application, when the n-type charge generation layer 105 is set, the n-type charge generation layer 105 actually corresponds to an electron generation layer (n-CGL) in the light-emitting functional layer, and the p-type charge generation layer 106 actually corresponds to a hole generation layer (p-CGL) in the light-emitting functional layer. By improving the performance of the n-CGL layer, the light-emitting effect and service life of the display panel are further improved.

[0051] Further, when the n-type charge generation layer 105 provided in the present application is set, the host material can be set by using the material of a common electron generation layer, such as any one of 2-(4-(phenanthrene-9-yl)naphthalene-1-yl)-1,10-phenanthroline, rubrene or other organic materials. The first metal ion 301 and the second metal ion 302 provided in the present application are doped in the above host material, so as to form the n-type charge generation layer 105 provided in the present application. Alternatively, the electron generation layer formed by other host materials is within the protection scope of the present application.

[0052] Further, in the embodiment of the present application, the film thickness of the n-type charge generation layer 105 is greater than or equal to the film thickness of the p-type charge generation layer 106, so as to effectively improve the performance of the n-type charge generation layer 105 by avoiding the increase of the total thickness of the light-emitting functional layer. Alternatively, the thickness of the n-type charge generation layer 105 is set to 18 nm-40 nm, and the thickness of the p-type charge generation layer 106 is set to 14 nm-27 nm. In the present application, the thickness of the n-type charge generation layer 105 is set to 18 nm-22 nm, and the thickness of the p-type charge generation layer 106 is set to 14 nm-17 nm, so as to reduce the overall thickness while ensuring the performance of the film layer.

[0053] Further, in the embodiment of the present application, when the first metal ion 301 and the second metal ion 302 in the n-type charge generation layer 105 are set, the first metal ion 301 and the second metal ion 302 can include one or a combination of Ag, Ca, Mg, Al, Na, Cs, Yb, Li ions. In the following embodiment, the first metal ion 301 is taken as Yb+ion, and the second metal ion 302 is taken as Li+ion. The atomic mass of the first metal ion is greater than the atomic mass of the second metal ion 302, so the mobility of the ion with a larger atomic mass is less than the mobility of the ion with a smaller atomic mass, and the diffusion rate of the ion with a smaller atomic mass is greater than the diffusion rate of the ion with a larger atomic mass. In the embodiment of the present application, the doping concentration of the high-mobility metal element is less than the doping concentration of the low-diffusion metal element. That is, the doping concentration of the first metal ion 301 is greater than the doping concentration of the second metal ion 302.

[0054] Specifically, when the n-type charge generation layer 105 is processed, the migration and diffusion speed of Yb+is relatively slow due to the large mass of Yb+, while the migration and diffusion speed of Li+is relatively fast due to the small mass of Li+. The migration effects of different ions can cause the n-type charge generation layer 105 to have different performances, or cause the n-type charge generation layer 105 to have different defects and thus reduce the performance. In this application, the doping concentration of Yb+is set to 1% to 15%, and the doping concentration of Li+is set to 0.05% to 10%. In one or more embodiments, the doping concentration of Yb+is set to 3%, 5%, 9%, 12%, and any one of 4% to 12%, and the doping concentration of Li+is set to 1%, 3%, 6%, 8%, and any one of 4% to 6%. Specifically, the corresponding doping concentration is selected according to the performance of the display panel.

[0055] For details Figure 2 In the embodiments of the present application, in the second direction Y, Yb+and Li+of different doping concentrations are arranged along the thickness direction of the n-type charge generation layer 105. Specifically, the doping concentration of Yb+on the side close to the p-type charge generation layer 106 is greater than the doping concentration on the side away from the p-type charge generation layer 106, and the doping concentration of Li+on the side close to the p-type charge generation layer 106 is less than the doping concentration on the side away from the p-type charge generation layer 106. Correspondingly, other film layers can also be selected as reference objects, such as the array substrate. At this time, the doping concentration of Yb+on the side close to the array substrate 100 is less than the doping concentration on the side away from the array substrate 100, and the doping concentration of Li+on the side close to the array substrate 100 is greater than the doping concentration on the side away from the array substrate 100.

[0056] Because the two different ions are doped in different ways, in order to avoid the performance uneven effect caused by different concentrations, in the embodiments of the present application, when the doping concentration is changed in the thickness direction, the absolute value of the change rate of the doping concentration of Yb+ions is the same as the change rate of the doping concentration of Li+. Specifically, from the bottom of the n-type charge generation layer 105 to the top of the n-type charge generation layer 105, the change rate of the doping concentration of Yb+ions is +2 in 1 unit thickness, and the change rate of the doping concentration of Li+ions is -2. Thus, the problem of performance unevenness caused by the change of the doping concentration of different ions is avoided, and the stability of the n-type charge generation layer 105 during operation is improved.

[0057] In the present application, along the second direction Y, the doping concentration of Yb+ decreases gradually from the bottom to the top of the n-type charge generation layer 105, such as linearly. The doping concentration of Li+ increases gradually, such as linearly. In this way, the Li+ with high concentration near the side of the first electron transport layer 104 has strong carrier transport capacity, which effectively reduces the cross voltage of the device, while the Li+ near the side of the p-type charge generation layer 106 has low concentration, and the low concentration of Li+ can significantly reduce the side reaction caused by ion diffusion, thereby improving the stability of the light-emitting functional layer during long-time high-temperature operation. Correspondingly, the n-type charge generation layer 105 is also provided with Yb+ ions, which can effectively inhibit the diffusion of Li+ to ensure the stability and service life of the n-type charge generation layer 105. On the other hand, Yb+ ions have relatively slow migration rate due to their large mass, which can ensure the stability of the n-type charge generation layer 105 during operation. In the present application, by adjusting the doping concentrations of Yb+ and Li+ in different regions, the formation of space charge regions at the interface between the n-type charge generation layer 105 and the p-type charge generation layer 106 can be avoided, and the occurrence of interface reactions can be prevented.

[0058] As shown in Figure 3 , Figure 3 the film thickness of the n-type charge generation layer 105 provided in the embodiments of the present application and the corresponding relationship of Yb+ and Li+ ions. In the present application, as the film thickness of the n-type charge generation layer 105 increases, the doping concentration of Li+ ions in the film gradually decreases as the film thickness increases, and the doping concentration of Yb+ ions in the film gradually increases as the film thickness increases.

[0059] In the embodiments of the present application, according to the concentration curve in Figure 3 , in the present application, the region between the bottom of the n-type charge generation layer 105 and the position at half the thickness of the n-type charge generation layer 105 is defined as the bottom region, and the region corresponding to the position at half the thickness of the n-type charge generation layer 105 to the top position of the n-type charge generation layer 105 is defined as the top region. In the embodiments of the present application, for Yb+ ions, the concentration change rate in the bottom region is greater than that in the top region, and for Li+ ions, the concentration decrease rate in the bottom region is less than that in the top region. Thus, on the one hand, the concentration range of Li+ ions at the interface between the n-type charge generation layer 105 and the p-type charge generation layer 106 can be ensured to ensure the ion mobility, and on the other hand, the stability of the device can be improved by controlling the content of Yb+ ions. At the same time, Yb+ ions and Li+ ions are provided with corresponding concentrations, and they can also interact with each other. For example, the Yb+ with the content range provided in the present application can effectively inhibit the diffusion of Li+, thereby achieving the purpose of device stability and service life.

[0060] AsFigure 4 As shown, Figure 4 This is a schematic diagram of the preparation process for the n-type charge generation layer 105 provided in an embodiment of the present application. To dope Yb+ and Li+ into the n-type charge generation layer 105, a substrate 500 is selected, and a Li+-containing material, a host material (n-CGL) containing the n-type charge generation layer, and a Yb+-containing material are placed in an evaporation apparatus. These different materials are placed in different locations.

[0061] Since the above-mentioned different materials are arranged at different positions, each material has a different evaporation angle relative to the base substrate 500. Figure 3 The angle range between each material and the substrate 500 is large near the front end of the evaporation process and small near the back end. This creates a doping gradient in which the corresponding ion concentration gradually increases as the thickness of the n-type charge generation layer 105 increases. During the evaporation process, angle limiting plates 501 are positioned corresponding to the materials at the various locations described above. With the cooperation of angle limiting plates 501, as the evaporation apparatus moves along direction T, a film of an n-type charge generation layer 105 with varying doping concentrations is prepared. Ultimately, the n-type charge generation layer 105 provided in this application is prepared.

[0062] Further, such as Figure 5 As shown, Figure 5 FIG. 1 is a schematic structural diagram of another n-type charge generation layer 105 provided in an embodiment of the present application. Figure 2 In the film layer structure, in the embodiment of the present application, in addition to performing variable doping treatment on Yb+ and Li+ in the second direction Y, variable doping treatment can also be performed on Yb+ and Li+ in the first direction X, so that in the first direction X, the above-mentioned different ions have corresponding concentrations.

[0063] See Figure 5 In the embodiment, the n-type charge generation layer 105 further includes a first region 601 and a second region 602, wherein the first region 601 is arranged on one side of the second region 602, thereby forming the entire n-type charge generation layer 105. In the present application, on the side close to the p-type charge generation layer 106, the doping concentration of Yb+ ions in the first region is greater than the doping concentration of Yb+ ions in the second region, and the doping concentration of Li+ ions in the first region is greater than the doping concentration of Li+ ions in the second region. In this way, a concentration gradient difference is also formed between the first region 601 and the second region 602 at the interface. When the n-type charge generation layer 105 is operating normally, the concentration gradient difference will help to increase the migration speed of Yb+ ions and Li+ ions, thereby effectively improving the performance of the n-type charge generation layer 105 while ensuring the stability of the n-type charge generation layer 105 film.

[0064] In the embodiment of the present application, when different doping concentrations are set in the first region 601 and the second region 602 corresponding to the first direction X, the film thickness of the n-type charge generation layer 105 corresponding to the first region 601 and the second region 602 is less than or equal to half of the total thickness of the n-type charge generation layer 105. Therefore, by controlling the film thickness of the above-mentioned regions, while ensuring that the n-type charge generation layer 105 has high performance, it is also effectively avoided that the n-type charge generation layer 105 is unstable due to excessive multi-dimensional concentration gradient differences in the first direction X and the second direction Y.

[0065] Further, such as Figure 6 As shown, Figure 6 The diagram of the film layer and energy level of the light-emitting functional layer provided in the embodiment of the present application is shown in FIG. Figure 1 In the film structure, taking the energy levels of some film layers as an example, the p-type charge generation layer 106 has a first Fermi level E1, and the corresponding n-type charge generation layer 105 has a second Fermi level E2. In the embodiment of the present application, the absolute value of the difference between the first Fermi level and the second Fermi level is 1.5eV to 2.2eV. Optionally, the first Fermi level E1 is set to 5.6eV to 6.9eV, and at the same time, the second Fermi level E2 is set to 2.0eV to 4.1eV. Therefore, by controlling the Fermi levels of the n-type charge generation layer 105 and the p-type charge generation layer 106 in the charge generation layer 20 in the present application, the internal charge movement effect of the light-emitting functional layer during operation is improved, thereby improving the performance and stability of the film layer.

[0066] Furthermore, the performance of the light-emitting device layer provided in the embodiment of the present application was tested, as shown in Table 1 below. The following table shows the performance parameters corresponding to different film layers:

[0067] Table 1: Performance parameters of each device

[0068]

[0069] According to the above performance parameters, the structure of the light-emitting functional layer in the display device provided in Comparative Example 1 and Comparative Example 2 is the same as that in the present application, but the n-type charge generation layer 105 and the p-type charge generation layer 106 in the light-emitting functional layer in Comparative Example 1 and Comparative Example 2 are not ion-doped, while the n-type charge generation layer 105 in the test example provided in the present application is doped with Yb+and Li+. The doping range of the above ions is doped according to the above set range. By comparison, in the present application, the n-type charge generation layer 105 layer is doped with a specific concentration, and Yb+and Li+are doped according to a specific rule, which effectively increases the current efficiency and service life, and reduces the driving voltage, thereby effectively improving the performance of the light-emitting functional layer.

[0070] Further, the present application also provides a display device, which comprises the display panel provided in the present application, and the light-emitting layer arranged in a stack in the display panel, and the light-emitting functional layer is arranged according to the stacking structure in the present application, so as to effectively improve the stability and service life of the charge generation layer in the light-emitting functional layer by doping the charge generation layer with specific ions.

[0071] In summary, the above describes in detail the display panel provided in the present application, and the principle and implementation manner of the present application are described by using specific examples. The above embodiment is only used to help understand the technical scheme of the present application and its core idea; although the present application is disclosed as above with preferred embodiments, the above preferred embodiments are not used to limit the present application, and any modification and decoration within the spirit and scope of the present application can be made by those skilled in the art, therefore, the protection scope of the present application is based on the range defined by the claims.

Claims

1. A display panel, characterized in that: include: A light-emitting functional layer, wherein the light-emitting functional layer at least comprises: a first light-emitting layer; a charge generation layer, disposed on one side of the first light-emitting layer; and a second light-emitting layer, disposed on a side of the charge generation layer away from the first light-emitting layer; The charge generation layer includes a first metal ion and a second metal ion, the atomic mass of the first metal ion is greater than the atomic mass of the second metal ion, and the doping concentration of the first metal ion is greater than the doping concentration of the second metal ion; In the thickness direction of the charge generation layer, the doping concentration of the first metal ion on the side close to the first light-emitting layer is lower than the doping concentration on the side away from the first light-emitting layer, and the doping concentration of the second metal ion on the side close to the first light-emitting layer is higher than the doping concentration on the side away from the first light-emitting layer.

2. The display panel according to claim 1, wherein: The doping concentration of the first metal ions is 1% to 15%, and the doping concentration of the second metal ions is 0.05% to 10%.

3. The display panel according to claim 1, wherein: The charge generation layer includes an n-type charge generation layer and a p-type charge generation layer, and the p-type charge generation layer is arranged on a side of the n-type charge generation layer away from the first light-emitting layer; The first metal ions and the second metal ions are both disposed in the n-type charge generation layer.

4. The display panel according to claim 3, wherein: The doping concentration of the first metal ion close to the p-type charge generation layer is greater than the doping concentration on the side away from the p-type charge generation layer, and the doping concentration of the second metal ion close to the p-type charge generation layer is less than the doping concentration on the side away from the p-type charge generation layer.

5. The display panel according to claim 3, wherein: The film thickness of the n-type charge generation layer is greater than the film thickness of the p-type charge generation layer.

6. The display panel according to claim 3, wherein: The p-type charge generation layer has a first Fermi level, and the n-type charge generation layer has a second Fermi level; The absolute value of the difference between the first Fermi level and the second Fermi level is 1.5 eV to 2.2 eV.

7. The display panel according to claim 3, wherein: In a first direction, the n-type charge generation layer includes a first region and a second region located on one side of the first region, and the first direction is parallel to the surface of the n-type charge generation layer; The doping concentration of the first metal ions in the first region is greater than the doping concentration in the second region.

8. The display panel according to any one of claims 1 to 7, characterized in that: The light-emitting functional layer further comprises: a first hole transport layer, wherein the first light-emitting layer is disposed on the first hole transport layer; a first electron transport layer, disposed on a side of the first light-emitting layer away from the first hole transport layer; a second hole transport layer, the charge generation layer being disposed between the second hole transport layer and the first electron transport layer; and The second electron transport layer is arranged on a side of the second light-emitting layer away from the second hole transport layer.

9. The display panel according to claim 1, wherein: In a thickness direction of the charge generation layer, an absolute value of a change rate of the doping concentration of the first metal ions is the same as an absolute value of a change rate of the doping concentration of the second metal ions.

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