Display panel, manufacturing method thereof and display device

Abstract

The invention discloses a display panel, a manufacturing method thereof and a display device, the display panel further comprises a suspension structure, and the suspension structure is located in a non-opening area and arranged on a pixel definition layer; the light-emitting unit comprises a bottom electrode, a light-emitting functional layer and a top electrode, the bottom electrode is arranged on the substrate, the light-emitting functional layer is arranged on the bottom electrode, and the top electrode is arranged on the light-emitting functional layer; the overhanging structures are used for separating the bottom electrodes of the two adjacent light-emitting units when the bottom electrodes are subjected to whole-surface deposition; wherein the suspension structure comprises a conductive part and a partition part, the partition part is arranged on the partition part, and the radial width of the partition part is larger than that of the conductive part. According to the display panel, the overhanging structure is arranged, so that the bottom electrode in the light-emitting unit is deposited on the whole surface through the overhanging structure, the light-emitting efficiency of the light-emitting unit is improved, and the quality of the display panel is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display panel and a manufacturing method thereof, and a display device. Background Art

[0002] OLED (Organic Light Emitting Diode) display devices are widely used in various fields due to their light weight, wide viewing angle, fast response, low temperature resistance, high luminous efficiency, and the ability to produce curved flexible displays. As mass production technology becomes increasingly mature, OLED display panels are gradually becoming mainstream real panels.

[0003] Existing organic light-emitting display panels mainly include two categories, one is an upright organic light-emitting display panel, wherein the light-emitting unit in the upright organic light-emitting display panel includes an anode, a light-emitting functional layer and a cathode stacked in sequence from a base substrate; the other is an inverted organic light-emitting display panel, which includes a cathode, a light-emitting functional layer and an anode stacked in sequence from a base substrate. For an upright organic light-emitting display panel, the active metal in the cathode is easily corroded by water and oxygen, resulting in a reduction in the life of the display panel. For an inverted organic light-emitting display panel, the active metal in the cathode is also easily oxidized during the manufacturing process or has problems such as process residues, resulting in low luminous efficiency of the inverted organic light-emitting display panel. In this regard, the art is in urgent need of a solution to the above problems. Summary of the invention

[0004] The purpose of the present application is to provide a display panel, a manufacturing method thereof and a display device. By setting a suspension structure, the bottom electrode in the light-emitting unit is deposited through the entire surface of the suspension structure without the need for an etching step, thereby reducing the possibility of active metals in the bottom electrode being oxidized during the process or having process residues, thereby improving the luminous efficiency of the light-emitting unit and improving the quality of the display panel.

[0005] The present application discloses a display panel, comprising a base substrate, a pixel definition layer and a light-emitting unit, wherein the pixel definition layer is arranged on the base substrate and is provided with a plurality of opening areas, and the light-emitting unit is arranged on the base substrate and is located in the opening area; the display panel also comprises an overhang structure, wherein the overhang structure is located in a non-opening area and is arranged on the pixel definition layer; the light-emitting unit comprises a bottom electrode, a light-emitting functional layer and a top electrode, wherein the bottom electrode is arranged on the base substrate, the light-emitting functional layer is arranged on the bottom electrode, and the top electrode is arranged on the light-emitting functional layer; the overhang structure is used to separate the bottom electrodes of two adjacent light-emitting units when the bottom electrode is deposited on the entire surface; wherein the overhang structure comprises a conductive portion and a partition portion, wherein the partition portion is arranged on the conductive portion, and the radial width of the partition portion is greater than the radial width of the conductive portion.

[0006] Optionally, the bottom electrode is a light-transmitting electrode, formed of one or both of magnesium material and silver material; the top electrode is formed of a reflective metal material, and a plurality of the light-emitting units share the top electrode; the light-emitting direction of the light-emitting unit is from the top electrode toward the bottom electrode.

[0007] Optionally, the thickness of the bottom electrode is greater than or equal to 100 angstroms and less than or equal to 300 angstroms; wherein the overhanging structure is also used to separate the light-emitting functional layers of two adjacent light-emitting units when the light-emitting functional layer is deposited on the entire surface.

[0008] Optionally, the top electrode is an anode, and the bottom electrode is a cathode; the light-emitting functional layer includes an electron transport layer, a light-emitting layer and a hole transport layer, the electron transport layer is arranged on the cathode, the light-emitting layer is arranged on the electron transport layer, the hole transport layer is arranged on the light-emitting layer, and the anode is arranged on the hole transport layer.

[0009] Optionally, the display panel also includes a cathode auxiliary electrode, which is formed of a transparent metal oxide material, is arranged under the cathode, and is electrically connected to the cathode; the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer.

[0010] Optionally, the conductive part is formed of a metal conductive material, and the overhanging structure is also used to separate the anodes of two adjacent light-emitting units when the anode is deposited on the entire surface, and the conductive part is used to connect the anodes of two adjacent light-emitting units; the radial width of the partition part is smaller than the radial width of the pixel definition layer; the thickness of the conductive part is greater than or equal to 0.1um and less than or equal to 1.5um, and the thickness of the partition part is greater than or equal to 0.03um and less than or equal to 0.2um.

[0011] The present application discloses a method for manufacturing a display panel, comprising the steps of:

[0012] Providing a substrate;

[0013] forming a pixel definition layer on the base substrate, and patterning the pixel definition layer to form a plurality of opening areas;

[0014] forming an overhang structure on the pixel definition layer;

[0015] The bottom electrode material is deposited on the entire surface, and the overhanging structure is used to separate the bottom electrodes of two adjacent light-emitting units;

[0016] Sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units;

[0017] The overhanging structure includes a conductive portion and a partition portion, wherein the partition portion is arranged on the conductive portion, and a radial width of the partition portion is greater than a radial width of the conductive portion.

[0018] Optionally, the step of forming a pixel definition layer on the substrate and patterning the pixel definition layer to form a plurality of opening areas includes:

[0019] Depositing cathode auxiliary electrode material on the substrate, and forming a cathode auxiliary electrode in the opening area after patterning;

[0020] A pixel definition layer is deposited and patterned on the cathode auxiliary electrode, the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer, and a plurality of opening areas are formed, and the cathode auxiliary electrodes are exposed from the opening areas.

[0021] Optionally, the step of sequentially forming a light-emitting functional layer and a top electrode in the opening region to form a plurality of light-emitting units includes:

[0022] Depositing the light-emitting functional layer material on the entire surface, and separating the light-emitting functional layers of two adjacent light-emitting units by an overhanging structure;

[0023] Depositing the anode on the entire surface to form a plurality of the light-emitting units;

[0024] Wherein, the top electrode is an anode, and the bottom electrode is a cathode; the light-emitting functional layer includes an electron transport layer, a light-emitting layer and a hole transport layer, the electron transport layer is arranged on the cathode, the light-emitting layer is arranged on the electron transport layer, the hole transport layer is arranged on the light-emitting layer, and the anode is arranged on the hole transport layer;

[0025] The bottom electrode is formed of magnesium or silver material, and is a light-transmitting electrode; the top electrode is formed of a reflective metal material, and is shared by a plurality of the light-emitting units; and the light emitting direction of the light-emitting unit is from the top electrode toward the bottom electrode.

[0026] The present application also discloses a display device, comprising a driving circuit and the above-mentioned display panel, wherein the driving circuit is used to drive the display panel to display.

[0027] The present application sets a suspension structure, and when forming the bottom electrode of the light-emitting unit, the bottom electrodes of multiple light-emitting units are separated by the suspension structure to form multiple independent and unconnected bottom electrodes. After completing the bottom electrode process, there is no need to use an etching process, and the light-emitting functional layer can be directly formed on the bottom electrode, reducing the impact of the etching process on the bottom electrode. In particular, when the bottom electrode includes an active metal material, the oxidation of the active metal and the residual problem in the etching are avoided, the film interface between the bottom electrode and the light-emitting functional layer is improved, the light-emitting efficiency of the light-emitting unit is improved, and the display effect of the display panel is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0029] Figure 1 is a schematic top view of a display panel according to a first embodiment of the present application;

[0030] Figure 2 yes Figure 1 Schematic diagram of the cross section along the cutting line AA;

[0031] Figure 3 is a schematic diagram of an inverted organic light emitting display panel of the present application;

[0032] Figure 4 is a cross-sectional schematic diagram of a second display panel of the present application;

[0033] Figure 5 is a schematic diagram of the steps of the method for manufacturing the display panel of the present application;

[0034] Figure 6 is a schematic diagram of the manufacturing process of the display panel of the present application;

[0035] Figure 7 is a schematic diagram of a display device of the present application.

[0036] Among them, 100, display panel; 101, opening area; 102, non-opening area; 110, base substrate; 120, pixel definition layer; 130, light-emitting unit; 131, anode; 132, light-emitting functional layer; 1321, electron transport layer; 1322, light-emitting layer; 1323, hole transport layer; 1324, electron injection layer; 1325, hole blocking layer; 1326, electron blocking layer; 1327, hole injection layer; 133, cathode; 134, cathode auxiliary electrode; 135, cathode redundant part; 140, overhang structure; 141, conductive part; 142, partition part; 150, drive circuit layer; 200, display device; 210, drive circuit. DETAILED DESCRIPTION

[0037] It should be understood that the terms used herein, the specific structures and functional details disclosed are only for describing specific embodiments and are representative, but the present application can be implemented in many alternative forms and should not be construed as being limited to only the embodiments described herein.

[0038] In the description of the present application, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, unless otherwise specified, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; "multiple" means two or more. In addition, the terms "upper", "lower", "left", "right", "vertical", "horizontal", etc. indicating orientation or positional relationships are described based on the orientation or relative positional relationships shown in the accompanying drawings, and are only for the convenience of describing the simplified description of the present application, rather than indicating that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0039] The present application is described in detail below with reference to the accompanying drawings and optional embodiments.

[0040] Figure 1 is a schematic top view of a display panel of the first embodiment of the present application, Figure 2 yes Figure 1 Schematic diagram of the cross section along the cutting line AA, see Figure 1-2As shown, the present application discloses a display panel 100, which includes a base substrate 110, a pixel definition layer 120, a light-emitting unit 130 and a suspension structure 140. The pixel definition layer 120 is arranged on the base substrate 110 and is provided with a plurality of opening areas 101. The light-emitting unit 130 is arranged on the base substrate 110 and is located in the opening area 101; the suspension structure 140 is located in a non-opening area 102 and is arranged on the pixel definition layer 120; the light-emitting unit 130 includes a bottom electrode, a light-emitting functional layer 101, and a bottom electrode. 32 and a top electrode, the bottom electrode is arranged on the base substrate 110, the light-emitting functional layer 132 is arranged on the bottom electrode, and the top electrode is arranged on the light-emitting functional layer 132; the overhanging structure 140 is used to separate the bottom electrodes of two adjacent light-emitting units 130 when the bottom electrode is deposited on the entire surface; wherein the overhanging structure 140 includes a conductive portion 141 and a partition portion 142, the partition portion 142 is arranged on the conductive portion 141, and the radial width of the partition portion 142 is greater than the radial width of the conductive portion 141.

[0041] The present application sets a suspension structure 140. When forming the bottom electrode of the light-emitting unit 130, the suspension structure 140 is used to separate the bottom electrodes of the plurality of light-emitting units 130, so as to form a plurality of independent and unconnected bottom electrodes. After the bottom electrode manufacturing process is completed, the light-emitting functional layer 132 can be directly formed on the bottom electrode without using an etching process, thereby reducing the influence of the etching process on the bottom electrode. In particular, when the bottom electrode includes an active metal material, the oxidation of the active metal and the residual problem in etching are avoided, the film interface between the bottom electrode and the light-emitting functional layer 132 is improved, the light-emitting efficiency of the light-emitting unit 130 is improved, and the display effect of the display panel 100 is improved.

[0042] Specifically, the display panel 100 of this embodiment is a bottom-emitting display panel 100, and the light emitted by the bottom-emitting display panel 100 is emitted from the top electrode to the bottom electrode. The bottom electrode is a light-transmitting electrode, which is formed of magnesium or silver material; the top electrode is formed of a reflective metal material, and the top electrode is shared by multiple light-emitting units 130; the light-emitting direction of the light-emitting unit 130 is from the top electrode toward the bottom electrode.

[0043] Specifically, the top electrode of the present application is a high-reflectivity opaque electrode, and the bottom electrode is a transparent electrode, so that light is emitted from the bottom, that is, a bottom-emitting display panel 100. The advantage of the bottom-emitting display panel 100 is that the anode 131 does not need to be light-transmissive, so the anode 131 can be made thick and formed on the entire surface, so that the resistance drop of the anode 131 formed on the entire surface at different positions is smaller than that of the entire cathode 133 formed by indium tin oxide in the upright top-emitting display panel 100, and the resistance drop at different positions is more uniform, avoiding different voltages at different positions. Moreover, after the light-emitting unit 130 completes the process, the emitted light does not emit from the encapsulation layer above the light-emitting unit 130. Therefore, the selectivity of the material and process of the encapsulation layer is greater, and better encapsulation of the light-emitting unit 130 can be achieved.

[0044] Figure 3 is a schematic diagram of an inverted organic light emitting display panel of the present application, see Figure 3 As shown, in order to further improve the luminous efficiency of the bottom-emitting display panel 100, the light-emitting functional layer 132 can be inverted in this embodiment. Among them, the top electrode in this embodiment is the anode 131, the bottom electrode is the cathode 133, and the light-emitting functional layer 132 includes an electron transport layer 1321, a light-emitting layer 1322 and a hole transport layer 1323. The electron transport layer 1321 is arranged on the cathode 133, the light-emitting layer 1322 is arranged on the electron transport layer 1321, the hole transport layer 1323 is arranged on the light-emitting layer 1322, and the anode 131 is arranged on the hole transport layer 1323. The electron transport layer 1321 is arranged on the side close to the cathode 133, and the hole transport layer 1323 is arranged on the side close to the anode 131. It is completely opposite to the light-emitting functional layer 132 in the light-emitting unit 130 of the upright organic light-emitting display panel 100. The electron transport layer 1321 in this embodiment is connected to the cathode 133 through the electron injection layer 1324, and a hole blocking layer 1325 is further provided between the electron transport layer 1321 and the light-emitting layer 1322. The hole transport layer 1323 is connected to the anode 131 through the hole injection layer 1327, and an electron blocking layer 1321 is further provided between the hole transport layer 1323 and the light-emitting layer 1322.

[0045] The present application adopts bottom emission technology in the inverted organic light-emitting display panel 100, that is, a light-transmitting cathode 133 is adopted, and an opaque anode 131 with strong reflective effect is adopted, so that light is emitted from the anode 131 arranged in the upper layer toward the cathode 133 arranged in the lower layer, thereby realizing bottom emission.

[0046] Generally speaking, for an inverted bottom-emitting display panel 100, if you want a higher luminous efficiency, the work function of the anode 131 needs to be relatively high, and the work function of the cathode 133 needs to be relatively low. When the anode 131 is selected as a reflective electrode and the cathode 133 is selected as a transparent electrode, the work function of the anode 131 will decrease and the work function of the cathode 133 will increase, resulting in the problem of low luminous efficiency of the inverted bottom-emitting display panel 100.

[0047] Therefore, it is necessary to add a light-transmitting active metal to the cathode 133 to reduce the work function of the cathode 133. For example, the cathode 133 in this embodiment can be a light-transmitting electrode formed of one or both of a magnesium material and a silver material as the cathode 133. Indium tin oxide (ITO) or indium zinc oxide (IZO) with a higher work function is added to the anode 131, for example, a layer of ITO or IZO material is formed on the anode 131 to increase the work function of the anode 131.

[0048] In the case of adding active metal to the cathode 133, two aspects need to be considered. The first aspect is the light transmittance of the active metal. The transmittance of the metal is related to its lattice structure, which refers to the way in which metal atoms are arranged according to a specific rule. When the lattice structure of the metal is tight enough and there is not enough space for photons to pass through, the metal will show an opaque characteristic. If the thickness of the metal is reduced to a certain extent, photons may pass through the lattice structure of the metal, making the metal translucent. On the other hand, the work function needs to be considered. While setting the thickness considering the light transmittance, the work function also needs to be taken into account, and its thickness also affects the work function. Generally speaking, taking the cathode 133 as an example of being formed of an active metal material, and the active metal material is magnesium or silver, the thickness of the cathode 133 needs to be smaller than the thickness of the reflective metal layer in the anode 131 to achieve a higher luminous efficiency. However, when the active metal material used for the cathode 133 is relatively thin, for example, 100 angstroms to 300 angstroms, it is easily oxidized during the deposition and etching steps in the process; specifically, in the etching process, there are also photoresist residues and etching problems, which will affect the work function of the cathode 133, thereby causing the inverted bottom-emitting display panel 100 to have a low luminous efficiency.

[0049] Furthermore, when the thickness of the bottom electrode, i.e., the cathode 133, of the present embodiment is greater than or equal to 100 angstroms and less than or equal to 300 angstroms, the partitioning effect of the overhanging structure 140 allows the cathode 133 to be formed into a plurality of independent and unconnected cathodes 133 without etching, so that the cathodes 133 of adjacent light-emitting units 130 are completely separated. Even if a partial cathode redundant portion 135 is formed on the overhanging structure 140, the partial cathode redundant portion 135 can be disconnected from the cathode 133 to prevent the problem of current crosstalk. In the present embodiment, the cathode 133 formed of an active metal material can reduce the work function of the cathode 133 to improve the phenomenon that hole injection and electron injection in the inverted organic light-emitting display panel 100 cannot be balanced, thereby solving the problem of low light-emitting efficiency of the current inverted organic light-emitting display panel 100.

[0050] Specifically, the anode 131 is formed by depositing a reflective metal material on the entire surface, and the multiple light-emitting units 130 share the anode 131; in order to match the work function of the cathode 133 and the light-emitting functional layer 132, the anode 131 of this embodiment can first adopt a sputtering process to form a thinner layer of indium tin oxide material with a thickness of about 0.01mm to 0.1mm, and then vacuum evaporate a reflective metal material with high reflectivity, which can generally be a silver material, and the thickness of the reflective metal material of the anode 131 is much thicker than the active metal material in the cathode 133.

[0051] It is worth mentioning that the display panel 100 of this embodiment can also be a top-emitting display panel 100, that is, the bottom electrode is formed by an opaque high-reflective electrode, and the top electrode is formed by a light-transmitting electrode, for example, the bottom electrode is an anode 131, and the top electrode is a cathode 133. The patterned bottom electrode is directly formed by the overhang structure 140, and there is no need to form the bottom electrode before the pixel definition layer 120 is formed. That is, the solution of forming the bottom electrode by the overhang structure 140 of the present application is also applicable to the top-emitting display panel 100, and also belongs to the protection scope of the present application.

[0052] Figure 4 is a cross-sectional schematic diagram of the second display panel of the present application, see Figure 4 As shown, specifically, the inverted bottom-emitting display panel 100 of this embodiment further includes a cathode auxiliary electrode 134, which is formed of a transparent metal oxide material, such as an ITO material or an IZO material. The cathode auxiliary electrode 134 is disposed under the cathode 133 and is electrically connected to the cathode 133; the cathode auxiliary electrodes 134 of two adjacent light-emitting units 130 are separated by the pixel definition layer 120.

[0053] In order to further improve the luminous efficiency of the inverted bottom-emitting light-emitting unit 130, the present embodiment further provides a cathode auxiliary electrode 134 below the cathode 133. The transparent metal oxide material of the cathode auxiliary electrode 134 includes an indium tin oxide material (ITO) or an indium zinc oxide material (IZO), and the light transmittance of such a material is greater than 90% of the metal material. The cathode auxiliary electrode 134 is connected to the pixel active switch in the driving circuit layer 150 through a via hole. It can be understood that a driving circuit layer 150 is also provided on the base substrate 110. The driving circuit layer 150 generally includes a pixel driving circuit of the light-emitting unit 130, such as a pixel active switch, a data driving line, a scanning control line, etc. The cathode 133 of each light-emitting unit 130 is connected to the pixel active switch through the cathode auxiliary electrode 134, and the voltage of the cathode 133 and the shutdown are controlled by the pixel active switch.

[0054] Specifically, the cathode auxiliary electrodes 134 of two adjacent light emitting units 130 are separated by the pixel definition layer 120. Considering that the cathode auxiliary electrode 134 needs to be directly connected to the cathode 133 of each light emitting unit 130, the cathode auxiliary electrodes 134 of adjacent light emitting units 130 also need to be spaced apart to avoid electrical crosstalk.

[0055] Specifically, the overhang structure 140 is also used to separate the light-emitting functional layers 132 of two adjacent light-emitting units 130 when the light-emitting functional layer 132 is deposited on the entire surface.

[0056] In the present application, after completing the evaporation of the cathode 133, the luminescent functional layer 132 can be directly evaporated in a vacuum environment, and the evaporation of the electron transport layer 1321, the luminescent layer 1322 and the hole transport layer 1323 can be completed in sequence, so that each opening area 101 forms an electron transport layer 1321, a luminescent layer 1322 and a hole transport layer 1323 that are not connected to each other.

[0057] Of course, in this embodiment, the light-emitting functional layer 132 is made of different materials when there are light-emitting functional layers 132 of different colors. Therefore, mask evaporation can be used to form different light-emitting functional layers 132 in different opening areas 101 .

[0058] Specifically, this embodiment further improves the overhang structure 140, including that the conductive portion 141 is formed of a metal conductive material, and the overhang structure 140 is also used to separate the anodes 131 of two adjacent light-emitting units 130 when the anode 131 is deposited on the entire surface, and the conductive portion 141 is used to connect the anodes 131 of two adjacent light-emitting units 130.

[0059] In the process of forming the anode 131, when the anode 131 layer used in the conductive portion 141 of the present embodiment is too thin to cover the overhang structure 140, the anode 131 material will also be separated by the overhang structure 140 in each opening area 101, that is, a plurality of independent anodes 131 that are not connected to each other are formed. However, under the drive of the light-emitting unit 130 of the present embodiment, the anodes 131 of the plurality of light-emitting units 130 do not need to be set with different driving voltages. Therefore, the anodes 131 of the plurality of light-emitting units 130 are directly connected through the conductive portion 141, so that the anode 131 forms a whole-surface electrode, and has the same driving voltage to drive the light-emitting unit 130, and different driving voltages are provided at the cathode 133 end to achieve different display effects for different light-emitting units 130.

[0060] Specifically, the thickness of the conductive portion 141 is greater than or equal to 0.1 um and less than or equal to 1.5 um, and the thickness of the partition portion 142 is greater than or equal to 0.03 um and less than or equal to 0.2 um.

[0061] When the thickness of the conductive part 141 is thin, it may not be able to play the role of isolating the cathode 133; and when the thickness of the conductive part 141 is thick, on the one hand, there is a problem of easy falling off, and on the other hand, there is also a problem of being difficult to etch. Therefore, in this embodiment, the thickness of the conductive part 141 is limited to be greater than or equal to 0.1um and less than or equal to 1.5um. The material of the conductive part 141 can be aluminum, molybdenum and silver materials or alloy materials of the above metals, and the partition part 142 is an insulating material or a metal material. The insulating material includes materials such as silicon oxide, silicon nitride and silicon oxynitride, and the metal material includes titanium and metal oxide materials (ITO or IZO). The thickness is generally between 0.03um and 0.2um.

[0062] Specifically, in the process of forming the overhang structure 140, the conductive part material and the partition part material are deposited on the entire surface in sequence. The partition part material is first etched away by a dry etching process, and the partition part material on the upper part of the pixel definition layer 120 is retained to form a partition part. The partition part is then used as a protective layer and the conductive part is etched by a wet etching process. Since the wet etching process is isotropic, the lower conductive part 141 will undergo side etching, thereby forming a conductive part 141 with a width smaller than the partition part 142. This structure is also called an eaves structure.

[0063] The radial width of the partition portion 142 is smaller than the radial width of the pixel definition layer 120 , and the width between the partition portion 142 and the conductive portion 141 needs to be adjusted according to the evaporation angle and the thickness of each film layer.

[0064] It is worth mentioning that when considering the conductive part 141 of the metal conductive material, it is also necessary to consider that the cathode 133 and the light-emitting functional layer 132 cannot contact the conductive part 141 to prevent the problem of electrical crosstalk. In practice, the evaporation angle of the above-mentioned materials during the evaporation process can be changed so that during evaporation, especially the cathode 133 and the light-emitting functional layer 132 will not contact the conductive part 141. When evaporating the anode 131, the evaporation angle of the anode 131 can be increased so that the anode 131 is connected to the conductive part 141 and conducts electricity. For the anode 131, the thickness of the anode 131 can also be increased so that it exceeds the height of the overhang structure 140, and the overhang structure 140 is completely covered, thereby forming a whole surface of the anode 131. Of course, in addition to the above-mentioned method of changing the evaporation angle, the width difference between the conductive part 141 and the partition part 142 can also be increased so that the cathode 133 and the light-emitting functional layer 132 are not connected to the conductive part 141.

[0065] In another embodiment, in order to prevent the conductive part 141 in the overhang structure 140 from contacting the cathode 133 or the light-emitting functional layer 132 , this embodiment may also use insulating material to replace the conductive part, so that the insulation of the overhang structure is stronger.

[0066] Figure 5 is a schematic diagram of the steps of the method for manufacturing the display panel of the present application, Figure 6 is a schematic diagram of the manufacturing process of the display panel of the present application, see Figure 5-6 As shown, the present application also discloses a method for manufacturing a display panel, comprising the steps of:

[0067] S110: providing a substrate;

[0068] S120: forming a pixel definition layer on the base substrate, and patterning the pixel definition layer to form a plurality of opening areas;

[0069] S130: forming an overhang structure on the pixel definition layer;

[0070] S140: depositing a bottom electrode material on the entire surface, wherein the overhanging structure is used to separate the bottom electrodes of two adjacent light-emitting units;

[0071] S150: forming a light-emitting functional layer and a top electrode in the opening area in sequence to form a plurality of light-emitting units.

[0072] The overhanging structure 140 includes a conductive portion 141 and a partition portion 142 . The partition portion 142 is disposed on the conductive portion 141 , and a radial width of the partition portion 142 is greater than a radial width of the conductive portion 141 .

[0073] Before S120 , the method further includes: forming a driving circuit layer on the base substrate, wherein the driving circuit layer includes a plurality of thin film transistors and driving circuits, and the thin film transistors and the driving circuits form a driving circuit for driving the plurality of light emitting units to emit light.

[0074] In this embodiment, by providing the overhang structure 140, when forming the bottom electrode of the light-emitting unit 130, the overhang structure 140 is used to separate the bottom electrodes between the multiple light-emitting units 130, so as to form multiple independent and unconnected bottom electrodes. After the bottom electrode manufacturing process is completed, the light-emitting functional layer 132 can be directly formed on the bottom electrode without using an etching process, thereby reducing the influence of the etching process on the bottom electrode. In particular, when the bottom electrode includes an active metal material, the oxidation of the active metal and the residual problem in etching are avoided, the film interface between the bottom electrode and the light-emitting functional layer 132 is improved, the light-emitting efficiency of the light-emitting unit 130 is improved, and the display effect of the display panel 100 is improved.

[0075] Specifically, the bottom electrode in this embodiment is a cathode 133, which is a light-transmitting electrode. The top electrode is an anode 131, which is a high-reflectivity light-proof electrode. The light-emitting functional layer 132 includes an electron transport layer 1321, a light-emitting layer 1322, and a hole transport layer 1323, wherein the electron transport layer 1321 is arranged on the cathode 133, the light-emitting layer 1322 is arranged on the electron transport layer 1321, the hole transport layer 1323 is arranged on the light-emitting layer 1322, and the anode 131 is arranged on the hole transport layer 1323. The electron transport layer 1321 is arranged on a side close to the cathode 133, and the hole transport layer 1323 is arranged on a side close to the anode 131. The display panel 100 of the present application is an inverted bottom-emitting display panel 100. The bottom electrode is formed of magnesium or silver material, and is a light-transmitting electrode; the top electrode is formed of a reflective metal material, and is shared by a plurality of the light-emitting units 130; and the light emitting direction of the light-emitting unit 130 is from the top electrode toward the bottom electrode.

[0076] The present application uses a process of depositing the cathode 133 material on the entire surface, thereby avoiding the problem of oxidation of the active metal material in the cathode 133 when etching the cathode 133 pattern, and also avoids the influence caused by the residual etching material during the etching process. It is worth mentioning that the present application uses the overhang structure 140 to form the cathode 133. By using an active metal as the cathode 133, on the one hand, oxidation of the active metal of the cathode 133 is avoided, and on the other hand, the work function of the cathode 133 can be reduced to improve the phenomenon that the hole injection and electron injection in the inverted organic light-emitting display panel 100 cannot be balanced, and solves the problem of low luminous efficiency of the current inverted organic light-emitting display panel 100.

[0077] The step S120 also includes the following steps:

[0078] S121: depositing a cathode auxiliary electrode material on the substrate, and forming a cathode auxiliary electrode in the opening area after patterning;

[0079] S122: depositing and patterning a pixel definition layer on the cathode auxiliary electrode, the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer, and a plurality of opening areas are formed, and the cathode auxiliary electrodes are exposed from the opening areas.

[0080] In this embodiment, after completing the process of the driving circuit layer 150, a cathode auxiliary electrode 134 is formed on the driving circuit layer 150, and at the via position of the driving circuit layer 150, the cathode auxiliary electrode 134 in each opening area 101 is connected to the output end of a thin film transistor to achieve the driving voltage of the cathode 133 being controlled and adjustable by the thin film transistor.

[0081] The steps of S130 include:

[0082] S131: sequentially depositing the conductive part material and the partition part material on the entire surface;

[0083] S132: removing the partition material in the opening area by a patterning process, and forming a partition in the non-opening area;

[0084] S133: using the partition portion as a protective layer, etching the conductive portion so that the width of the conductive portion is smaller than the width of the partition portion to form a hanging structure.

[0085] The conductive part material and the partition part material are sequentially deposited on the entire surface, and the partition part is used as a protective layer. The conductive part is etched by a wet etching process. Since the wet etching process is isotropic, the lower conductive part 141 will be side-etched, so that the width of the conductive part 141 is smaller than the width of the partition part 142. The etching of the partition part material can be selected as a dry etching process.

[0086] The steps of S150 include:

[0087] S151: depositing the light-emitting functional layer material on the entire surface, and separating the light-emitting functional layers of two adjacent light-emitting units by an overhanging structure;

[0088] S152: Depositing the anode on the entire surface to form a plurality of the light-emitting units.

[0089] In this solution, the light-emitting functional layers 132 of two adjacent light-emitting units 130 are separated by the overhang structure 140, so that the light-emitting functional layers 132 of adjacent light-emitting units 130 are not directly connected, and the material of the light-emitting functional layer 132 is separated by setting the thickness of the partition part 142 and the conductive part 141 of the overhang structure 140. Specifically, the light-emitting functional layer 132 can be selectively separated by changing the thickness of the partition part 142 and the conductive part 141, for example, to separate to one of the electron transport layer 1321, the light-emitting layer 1322, and the hole transport layer 1323.

[0090] It is worth mentioning that another important factor is that the thicker the conductive part 141 is, the stronger the isolation capability of the overhanging structure 140 is, and when the anode 131 is formed, the anode 131 is also isolated, so the thickness of the conductive part 141 cannot be too large. Therefore, the thickness of the conductive part 141 is greater than or equal to 0.1um and less than or equal to 1.5um, and the thickness of the isolation part 142 is greater than or equal to 0.03um and less than or equal to 0.2um.

[0091] Of course, in order to make the overhang structure 140 have a good partitioning effect, even if the subsequent anode 131 is separated by the overhang structure 140, it can be connected using the conductive part 141 in the overhang structure 140. The conductive part 141 can be formed of metal material, and the partition part 142 can be formed of insulating material. When the anode 131 is separated by the overhang structure 140, the evaporation angle of the anode 131 is adjusted so that the anode 131 is directly overlapped on the conductive part 141, and the conductive part 141 is connected to form the entire surface of the anode 131.

[0092] Figure 7 is a schematic diagram of the display device of the present application, see Figure 7 As shown, the present application further discloses a display device 200 , which includes a driving circuit 210 and a display panel 100 of any one of the above embodiments, wherein the driving circuit 210 is used to drive the display panel 100 to display.

[0093] It should be noted that the inventive concept of the present application can form a large number of embodiments, but the length of the application document is limited and it is impossible to list them one by one. Therefore, under the premise of no conflict, the embodiments or technical features described above can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effects will be enhanced.

[0094] The above contents are further detailed descriptions of the present application in combination with specific optional implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be deemed to fall within the scope of protection of the present application.

Claims

1. A display panel, comprising a base substrate, a pixel definition layer and a light-emitting unit, wherein the pixel definition layer is disposed on the base substrate and has a plurality of opening areas, and the light-emitting unit is disposed on the base substrate and is located in the opening areas; characterized in that: The display panel further includes an overhang structure, which is located in the non-opening area and is disposed on the pixel definition layer; The light-emitting unit comprises a bottom electrode, a light-emitting functional layer and a top electrode, wherein the bottom electrode is arranged on the substrate, the light-emitting functional layer is arranged on the bottom electrode, and the top electrode is arranged on the light-emitting functional layer; The overhanging structure is used to separate the bottom electrodes of two adjacent light-emitting units when the bottom electrode is deposited on the entire surface; The overhanging structure includes a conductive portion and a partition portion, the partition portion is arranged on the conductive portion, and a radial width of the partition portion is greater than a radial width of the conductive portion.

2. The display panel according to claim 1, characterized in that: The bottom electrode is a light-transmitting electrode, and is formed of one or both of magnesium material and silver material; The top electrode is formed of a reflective metal material, and the top electrode is shared by a plurality of the light-emitting units; The light output of the light emitting unit is emitted from one side of the base substrate.

3. The display panel according to claim 2, characterized in that: The thickness of the bottom electrode is greater than or equal to 100 angstroms and less than or equal to 300 angstroms; Wherein, the overhang structure is also used to separate the light-emitting functional layers of two adjacent light-emitting units when the light-emitting functional layer is deposited on the entire surface.

4. The display panel according to claim 2, characterized in that: The top electrode is an anode, and the bottom electrode is a cathode; the light-emitting functional layer includes an electron transport layer, a light-emitting layer and a hole transport layer, the electron transport layer is arranged on the cathode, the light-emitting layer is arranged on the electron transport layer, the hole transport layer is arranged on the light-emitting layer, and the anode is arranged on the hole transport layer.

5. The display panel according to claim 4, characterized in that: The display panel further includes a cathode auxiliary electrode, the cathode auxiliary electrode is formed of a transparent metal oxide material, the cathode auxiliary electrode is arranged under the cathode and is electrically connected to the cathode; The cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer.

6. The display panel according to claim 5, characterized in that: The conductive part is formed of a metal conductive material, and the overhanging structure is also used to separate the anodes of two adjacent light-emitting units when the anode is deposited on the entire surface, and the conductive part is used to connect the anodes of two adjacent light-emitting units; The radial width of the partition portion is smaller than the radial width of the pixel definition layer; The thickness of the conductive portion is greater than or equal to 0.1 um and less than or equal to 1.5 um, and the thickness of the partition portion is greater than or equal to 0.03 um and less than or equal to 0.2 um.

7. A method for manufacturing a display panel, characterized in that: Includes steps: Providing a substrate; forming a pixel definition layer on the base substrate, and patterning the pixel definition layer to form a plurality of opening areas; forming an overhang structure on the pixel definition layer; The bottom electrode material is deposited on the entire surface, and the overhanging structure is used to separate the bottom electrodes of two adjacent light-emitting units; Sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units; The overhanging structure includes a conductive portion and a partition portion, wherein the partition portion is arranged on the conductive portion, and a radial width of the partition portion is greater than a radial width of the conductive portion.

8. The method for manufacturing a display panel according to claim 7, characterized in that: The step of forming a pixel definition layer on the substrate and patterning the pixel definition layer to form a plurality of opening areas includes: Depositing cathode auxiliary electrode material on the substrate, and forming a cathode auxiliary electrode in the opening area after patterning; A pixel definition layer is deposited and patterned on the cathode auxiliary electrode, the cathode auxiliary electrodes of two adjacent light-emitting units are separated by the pixel definition layer, and a plurality of opening areas are formed, and the cathode auxiliary electrodes are exposed from the opening areas.

9. The method for manufacturing a display panel according to claim 7, characterized in that: The step of sequentially forming a light-emitting functional layer and a top electrode in the opening area to form a plurality of light-emitting units includes: Depositing the light-emitting functional layer material on the entire surface, and separating the light-emitting functional layers of two adjacent light-emitting units by an overhanging structure; Depositing the anode on the entire surface to form a plurality of the light-emitting units; Wherein, the top electrode is an anode, and the bottom electrode is a cathode; the light-emitting functional layer includes an electron transport layer, a light-emitting layer and a hole transport layer, the electron transport layer is arranged on the cathode, the light-emitting layer is arranged on the electron transport layer, the hole transport layer is arranged on the light-emitting layer, and the anode is arranged on the hole transport layer; The cathode is formed of one or both of magnesium material and silver material, and is a light-transmitting electrode; the anode is formed of a reflective metal material, and multiple light-emitting units share the anode; and the light emitted by the light-emitting unit is emitted from one side of the substrate.

10. A display device, characterized in that: It comprises a driving circuit and the display panel according to any one of claims 1 to 6, wherein the driving circuit is used to drive the display panel to display.

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