Manufacturing method of display panel, display panel and display device

Abstract

The application discloses a manufacturing method of a display panel, a display panel and a display device. The manufacturing method comprises the following steps: providing a substrate; forming a pixel definition layer on the substrate, patterning the pixel definition layer to form a plurality of opening areas, and forming a overhanging structure on the pixel definition layer; sequentially depositing a bottom electrode material, a first color light-emitting functional layer material and a top electrode material in a plurality of first opening areas to form a first color light-emitting unit; sequentially depositing the bottom electrode material, the second color light-emitting functional layer material and the top electrode material in a plurality of second opening areas to form a second color light-emitting unit; and sequentially depositing the bottom electrode material, a third color light-emitting functional layer material and the top electrode material in a plurality of third opening areas to form a third color light-emitting unit. 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] This application relates to the field of display technology, and in particular to a method for manufacturing a display panel, a display panel, and a display device. Background Technology

[0002] OLED (Organic Light Emitting Diode) display devices are widely used in various fields due to their lightweight, wide viewing angle, fast response, low-temperature resistance, high luminous efficiency, and the ability to fabricate flexible displays. As mass production technology matures, OLED display panels are gradually becoming the mainstream display panels.

[0003] Existing organic light-emitting diode (OLED) display panels mainly fall into two categories: upright OLED panels, where the light-emitting unit comprises an anode, a light-emitting functional layer, and a cathode sequentially stacked on a substrate; and inverted OLED panels, which also include a cathode, a light-emitting functional layer, and an anode sequentially stacked on a substrate. In upright OLED panels, the active metal in the cathode is susceptible to corrosion by water and oxygen, leading to a reduced lifespan. In inverted OLED panels, the active metal in the cathode is also prone to oxidation during the manufacturing process or may have process residues, resulting in low luminous efficiency. Therefore, a solution to these problems is urgently needed in the field. Summary of the Invention

[0004] The purpose of this application is to provide a method for manufacturing a display panel, a display panel, and a display device. By setting a suspension structure, the bottom electrode in the light-emitting unit is deposited on the entire surface through the suspension structure without the need for an etching step. This reduces the possibility that the active metal in the bottom electrode will be oxidized or have process residues during the manufacturing process, thereby improving the luminous efficiency of the light-emitting unit and enhancing the quality of the display panel.

[0005] This application discloses a method for manufacturing a display panel, including the following steps:

[0006] Provide a substrate;

[0007] A pixel definition layer is formed on the substrate, and the pixel definition layer is patterned to form a plurality of opening regions, wherein the opening regions include a first opening region, a second opening region and a third opening region;

[0008] A drooping structure is formed on the pixel definition layer;

[0009] A bottom electrode material, a first color emitting functional layer material, and a top electrode material are sequentially deposited in multiple first opening regions to form a first color emitting unit;

[0010] A bottom electrode material, a second color emitting functional layer material, and a top electrode material are sequentially deposited in multiple second opening regions to form a second color emitting unit; and

[0011] A bottom electrode material, a third color emitting functional layer material, and a top electrode material are sequentially deposited in multiple third opening regions to form a third color emitting unit;

[0012] The bottom electrode of the first color light-emitting unit, the bottom electrode of the second color light-emitting unit, and the bottom electrode of the third color light-emitting unit are separated by the suspension structure.

[0013] Optionally, the bottom electrode of the first color light-emitting unit, the bottom electrode of the second color light-emitting unit, and the bottom electrode of the third color light-emitting unit are made of the same material and formed in different processes.

[0014] Optionally, the step of forming a pixel definition layer on the substrate and patterning the pixel definition layer to form a plurality of opening regions includes:

[0015] A cathode auxiliary electrode material is deposited on the substrate, and after patterning, cathode auxiliary electrodes are formed in the first opening region, the second opening region, and the third opening region, respectively.

[0016] A pixel definition layer is deposited and patterned on the cathode auxiliary electrode, and two adjacent cathode auxiliary electrodes are separated by the pixel definition layer. Multiple cathode auxiliary electrodes are exposed from the second opening region, the second opening region and the third opening region, respectively.

[0017] Optionally, the step of forming a dangling structure on the pixel definition layer includes:

[0018] The conductive material and the partition material are deposited sequentially over the entire surface;

[0019] The partition material in the opening area is removed by a patterning process, and the partition is formed in the non-opening area.

[0020] Using the partition as a protective layer, the conductive part is etched so that the width of the conductive part is smaller than the width of the partition to form a hanging structure.

[0021] Optionally, the step of sequentially depositing a bottom electrode material, a first color emitting functional layer material, and a top electrode material in a plurality of first opening regions to form a first color emitting unit includes:

[0022] The bottom electrode material, the first color luminescent functional layer material, and the top electrode material are deposited sequentially across the entire surface by vapor deposition.

[0023] Remove the bottom electrode material, the first color emitting functional layer material, and the top electrode material from the second opening region and the third opening region, and retain the bottom electrode material, the first color emitting functional layer material, and the top electrode material from the first opening region to form a first color emitting unit;

[0024] The step of sequentially depositing a bottom electrode material, a second color emitting functional layer material, and a top electrode material in a plurality of second opening regions to form a second color emitting unit includes:

[0025] The bottom electrode material, the second color luminescent functional layer material, and the top electrode material are deposited sequentially on the entire surface by vapor deposition.

[0026] Remove the bottom electrode material, the second color emitting functional layer material, and the top electrode material from the first opening region and the third opening region, and retain the bottom electrode material, the second color emitting functional layer material, and the top electrode material from the second opening region to form a second color emitting unit;

[0027] The step of sequentially depositing a bottom electrode material, a third color emitting functional layer material, and a top electrode material in multiple third opening regions to form a third color emitting unit includes:

[0028] The bottom electrode material, the third color luminescent functional layer material, and the top electrode material are deposited sequentially across the entire surface by vapor deposition.

[0029] Remove the bottom electrode material, the second color emitting functional layer material, and the top electrode material from the first opening area and the second opening area, and retain the bottom electrode material, the second color emitting functional layer material, and the top electrode material from the third opening area to form a third color emitting unit;

[0030] The top electrode of the first opening region, the top electrode of the second opening region, and the top electrode of the third opening region are electrically connected to each other through the conductive part.

[0031] Optionally, the step of removing the bottom electrode material, the first color emitting functional layer material, and the top electrode material from the second and third opening regions may further include:

[0032] An etching protective layer is formed on the top electrode material of the first opening region;

[0033] Before the step of removing the bottom electrode material, the second color luminescent functional layer material, and the top electrode material from the first opening region and the third opening region, the method further includes:

[0034] An etching protective layer is formed on the top electrode material of the second opening region;

[0035] Before the step of removing the bottom electrode material, the second color luminescent functional layer material, and the top electrode material from the first opening region and the second opening region, the following steps are included:

[0036] An etching protective layer is formed on the top electrode material of the third opening region.

[0037] Optionally, the first color light-emitting unit, the second color light-emitting unit, and the third color light-emitting unit each include a bottom electrode and a top electrode, wherein the top electrode is an anode and the bottom electrode is a cathode; the bottom electrode is a light-transmitting electrode and is formed using one or two of magnesium and silver materials, and the top electrode is formed using a reflective metal material;

[0038] Optionally, the thickness of the bottom electrode is greater than or equal to 100 angstroms and less than or equal to 300 angstroms; the first color emitting functional layer, the second color emitting functional layer and the third color emitting functional layer each include an electron transport layer and a hole transport layer, the electron transport layer is disposed on the side near the cathode, the hole transport layer is disposed on the side near the anode, the electron transport layer is disposed on the cathode, the hole transport layer is disposed on the electron transport layer, and the anode is disposed on the hole transport layer.

[0039] This application also discloses a display panel formed by the above-described method of manufacturing a display panel. The display panel includes a substrate, a pixel definition layer, a suspension structure, a first color light-emitting unit, a second color light-emitting unit, and a third color light-emitting unit. The pixel definition layer is disposed on the substrate and has multiple opening regions, including a first opening region, a second opening region, and a third opening region. The suspension structure is disposed on the pixel definition layer and is located in a non-opening region. The first color light-emitting unit is disposed in the first opening region. The second color light-emitting unit is disposed in the second opening region. The third color light-emitting unit is disposed in the third opening region. The bottom electrode of the first color light-emitting unit, the bottom electrode of the second color light-emitting unit, and the bottom electrode of the third color light-emitting unit are separated by the suspension structure.

[0040] This application also discloses a display device, including a driving circuit and the aforementioned display panel, wherein the driving circuit is used to drive the display panel to display.

[0041] In this application, when forming the bottom electrode of the light-emitting unit, a suspended structure is used to separate the bottom electrodes of multiple light-emitting units, forming multiple independent and unconnected bottom electrodes. After completing the bottom electrode fabrication process, no etching process is required, and the light-emitting functional layer of the light-emitting unit can be directly formed on the bottom electrode, reducing the impact of the etching process on the bottom electrode. Especially when the bottom electrode includes an active metal material, the oxidation of the active metal and the residue problems existing in the etching process are avoided, improving the film interface between the bottom electrode and the light-emitting functional layer, improving the luminous efficiency of the light-emitting unit, and enhancing the display effect of the display panel. Attached Figure Description

[0042] The accompanying drawings, which form part of the specification, are used to provide a further understanding of the embodiments of this application and illustrate the implementation methods of this application, together with the textual description, to explain the principles of this application. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort. In the drawings:

[0043] Figure 1 This is a schematic diagram illustrating the steps of the method for manufacturing the display panel of this application;

[0044] Figure 2 This is a schematic diagram illustrating the manufacturing process of the display panel of this application;

[0045] Figure 3 This is a schematic diagram of the display panel of this application;

[0046] Figure 4 This is a schematic diagram of the inverted light-emitting unit of this application;

[0047] Figure 5 This is a schematic diagram illustrating the steps of a method for manufacturing a display panel according to another embodiment of this application;

[0048] Figure 6 This is a schematic diagram illustrating the manufacturing process of a display panel according to another embodiment of this application;

[0049] Figure 7 This is a schematic diagram of the display device of this application.

[0050] Among them, 100 is a display panel; 101 is an opening area; 101a is a first opening area; 101b is a second opening area; 101c is a second opening area; 102 is a non-opening area; 110 is a substrate; 111 is a pixel definition layer; 120 is a hanging structure; 121 is a conductive part; 122 is a partition part; 130R is a first color light-emitting unit; 130G is a second color light-emitting unit; 130B is a third color light-emitting unit; 131 is an anode; 132 is a light-emitting functional layer; 1321 is an electron transport layer; 1322 is a light-emitting layer; 1323 is a hole transport layer; 1324 is an electron injection layer; 1325 is a hole blocking layer; 1326 is an electron blocking layer; 1327 is a hole injection layer; 133 is a cathode; 134 is a cathode auxiliary electrode; 135 is an etching protection layer; 150 is a pixel driving layer; 200 is a display device; and 210 is a driving circuit. Detailed Implementation

[0051] It should be understood that the terminology, specific structural and functional details used herein are merely for describing particular embodiments and are representative. However, this application may be implemented in many alternative forms and should not be construed as being limited to the embodiments set forth herein.

[0052] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of technical features indicated. Therefore, unless otherwise stated, a feature specified as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. Furthermore, terms indicating orientation or positional relationships, such as "upper," "lower," "left," "right," "vertical," and "horizontal," are described based on the orientation or relative positional relationships shown in the accompanying drawings and are only for the purpose of simplifying the description of this application, not indicating that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0053] The present application will now be described in detail with reference to the accompanying drawings and optional embodiments.

[0054] Figure 1 This is a schematic diagram illustrating the steps of the method for manufacturing the display panel of this application. Figure 2 This is a schematic diagram of the manufacturing process of the display panel of this application. See [link / reference]. Figures 1 to 2 As shown, this application discloses a method for manufacturing a display panel, including the following steps:

[0055] S10: Provides a substrate;

[0056] S20: A pixel definition layer is formed on the substrate, and the pixel definition layer is patterned to form a plurality of opening regions, wherein the opening regions include a first opening region, a second opening region and a third opening region;

[0057] S30: A hanging structure is formed on the pixel definition layer;

[0058] S40: Sequentially deposit a bottom electrode material, a first color emitting functional layer material, and a top electrode material in a plurality of first opening regions to form a first color emitting unit;

[0059] S50: Sequentially depositing a bottom electrode material, a second color emitting functional layer material, and a top electrode material in multiple second opening regions to form a second color emitting unit; and

[0060] S60: A bottom electrode material, a third color emitting functional layer material, and a top electrode material are sequentially deposited in multiple third opening regions to form a third color emitting unit;

[0061] The bottom electrode of the first color light-emitting unit, the bottom electrode of the second color light-emitting unit, and the bottom electrode of the third color light-emitting unit are separated by the suspension structure.

[0062] In this application, when forming the bottom electrode of the light-emitting unit, a suspended structure is used to separate the bottom electrodes of multiple light-emitting units, forming multiple independent and unconnected bottom electrodes. After completing the bottom electrode fabrication process, no etching process is required, and the light-emitting functional layer of the light-emitting unit can be directly formed on the bottom electrode, reducing the impact of the etching process on the bottom electrode. Especially when the bottom electrode includes an active metal material, the oxidation of the active metal and the residue problems existing in the etching process are avoided, improving the film interface between the bottom electrode and the light-emitting functional layer, improving the luminous efficiency of the light-emitting unit, and enhancing the display effect of the display panel.

[0063] The first color emitting unit can be a red emitting unit, emitting red light; the second color emitting unit can be a green emitting unit, emitting green light; and the third color emitting unit can be a blue emitting unit, emitting blue light. The main difference between the red, green, and blue emitting units lies in the materials used in the emitting functional layer, allowing each unit to emit different colors of light when excited by holes and electrons.

[0064] It is understood that the manufacturing sequence of the red, green, and blue light-emitting units in this application is not limited. Any color of light-emitting unit can be manufactured first, followed by the sequential formation of other colors. Of course, the color of the light-emitting units in this application is not limited to red, green, and blue; for example, white and yellow light-emitting units are also applicable. For the first, second, and third opening regions, they are distinguished only by the color of the light-emitting units within each opening region. Multiple first opening regions may contain light-emitting units of the same color, and the terms "first," "second," and "third" do not limit the order or size of the opening regions.

[0065] Figure 3 This is a schematic diagram of the display panel of this application; see below. Figure 3As shown, this application also discloses a display panel 100, which is formed using the above-described manufacturing method. The display panel 100 includes a substrate 110, a pixel definition layer 111, a suspension structure 120, a first color light-emitting unit 130R, a second color light-emitting unit 130G, and a third color light-emitting unit 130B. The pixel definition layer 111 is disposed on the substrate 110 and has a plurality of opening regions 101, including a first opening region 101a, a second opening region 101b, and a third opening region 101c. The suspension structure 120... 0 is disposed on the pixel definition layer 111 and located in the non-opening area 102; the first color light-emitting unit 130R is disposed in the first opening area 101a; the second color light-emitting unit 130G is disposed in the second opening area 101b; the third color light-emitting unit 130B is disposed in the third opening area 101c; wherein, the bottom electrode of the first color light-emitting unit 130R, the bottom electrode of the second color light-emitting unit 130G, and the bottom electrode of the third color light-emitting unit 130B are separated by the suspension structure 120; the suspension structure 120 includes a conductive part 121 and a blocking part 122.

[0066] Figure 4 This is a schematic diagram of the inverted light-emitting unit of this application, see [link / reference]. Figure 4As shown, the light-emitting unit in this embodiment is an inverted organic light-emitting unit. The first color light-emitting unit 130R includes a bottom electrode, a first color light-emitting functional layer, and a top electrode. The second color light-emitting unit 130G includes a bottom electrode, a second color light-emitting functional layer, and a top electrode. The third color light-emitting unit 130B includes a bottom electrode, a third color light-emitting functional layer, and a top electrode. The first color light-emitting functional layer, the second color light-emitting functional layer, and the third color light-emitting functional layer are respectively inverted. The main difference between them is that the light-emitting layer materials are different, but the film structure is the same, which is a basic film layer with a light-emitting functional layer. Specifically, the bottom electrode is the cathode 133, the top electrode is the anode 131, 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 disposed on the cathode 133, the light-emitting layer 1322 is disposed on the electron transport layer 1321, the hole transport layer 1323 is disposed on the light-emitting layer 1322, and the anode 131 is disposed on the hole transport layer 1323. The electron transport layer 1321 is disposed on the side closer to the cathode 133, and the hole transport layer 1323 is disposed on the side closer to the anode 131. This 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. In this embodiment, the electron transport layer 1321 is connected to the cathode 133 through an electron injection layer 1324, and a hole blocking layer 1325 is also disposed between the electron transport layer 1321 and the light-emitting layer 1322. Hole transport layer 1323 is connected to anode 131 via hole injection layer 1327. Electron blocking layer 1321 is also disposed between hole transport layer 1323 and light-emitting layer 1322. The second color light-emitting functional layer and the third color light-emitting functional layer have basically the same structure as the first color light-emitting functional layer, except that the materials used in the light-emitting layer are different. For example, the red light-emitting unit uses a red light-emitting layer, the green light-emitting unit uses a green light-emitting layer, and the blue light-emitting unit uses a blue light-emitting layer.

[0067] The inverted organic light-emitting unit of this application can employ top-emitting or bottom-emitting technology. When bottom-emitting technology is selected, the lower cathode needs to be transparent, and the upper anode needs to have high reflectivity. In this embodiment, when the inverted organic light-emitting unit is a bottom-emitting type, it has better light emission efficiency. The light emission direction is from the cathode towards the substrate 110, thus achieving light emission display from the back of the substrate 110. Relatively speaking, the luminous efficiency of the light-emitting unit in the inverted bottom-emitting display panel 100 is affected by the work function of the cathode and anode. Generally, when the work function of the anode is relatively high and the work function of the cathode is relatively low, the light-emitting unit has higher luminous efficiency. However, when the anode is selected as a reflective electrode and the cathode as a transparent electrode, the work function of the anode decreases, and the work function of the cathode increases, resulting in lower luminous efficiency of the inverted bottom-emitting display panel 100.

[0068] Therefore, in this embodiment, the cathode needs to have an increased amount of light-transmitting active metal to reduce the work function of the cathode, so that the work function of the cathode matches that of the anode, thereby achieving a better light output effect.

[0069] Specifically, the bottom electrode of this application is a cathode, and the bottom electrode material is formed from one or two of magnesium and silver materials. The top electrode is formed from a reflective metal material. It is understood that the first color light-emitting unit 130R, the second color light-emitting unit 130G, and the third color light-emitting unit 130B in this embodiment each include a bottom electrode and a top electrode. The bottom and top electrode materials used in these different color light-emitting units are identical. In the following description, the definitions of bottom and top electrodes apply to light-emitting units of different colors, and will not be repeated here.

[0070] Of course, this embodiment also applies to light-emitting units where the first color light-emitting unit 130R, the second color light-emitting unit 130G, and the third color light-emitting unit 130B are all the same color, such as a white light-emitting unit. In this case, the bottom electrode can be formed simultaneously, i.e., formed in the same process. For different colors, such as the first color light-emitting unit 130R being a red light-emitting unit, the second color light-emitting unit 130G being a green light-emitting unit, and the third color light-emitting unit 130B being a blue light-emitting unit, the three different colored bottom electrodes can be formed in different processes. That is, after completing the cathode, red light-emitting functional layer, and anode of the red light-emitting unit, after completing the cathode, green light-emitting functional layer, and anode of the green light-emitting unit, the cathode, blue light-emitting functional layer, and anode of the blue light-emitting unit are finally formed, thus completing the process of the light-emitting unit sequentially.

[0071] When the cathode is formed using one or both of magnesium and silver materials, two aspects need to be considered. First, the light transmittance of the metal must be considered. The light transmittance of a metal is related to its crystal lattice, which refers to the arrangement of metal atoms according to a specific pattern. When the metal's crystal lattice is sufficiently dense, leaving insufficient space for photons to pass through, the metal will exhibit opaque properties. However, if the metal's thickness is reduced to a certain level, photons may be able to pass through the metal's crystal lattice, making the metal transparent. Second, the work function also needs to be considered. While setting the thickness based on light transmittance, the work function must also be taken into account, as the thickness also affects the work function. Generally, taking an active metal material, such as magnesium or silver, as an example, the cathode thickness needs to be smaller than the thickness of the reflective metal layer in the anode to achieve higher luminous efficiency. However, when the active metal material used in the cathode is thin, such as between 100 and 300 angstroms, oxidation can easily occur during the deposition and etching steps in the manufacturing process. Specifically, in the etching process, there are also issues such as photoresist residue and etching problems, all of which affect the work function of the cathode, resulting in lower luminous efficiency of the inverted bottom-emitting display panel 100. Therefore, when forming the cathode of the light-emitting unit, the cathodes of multiple light-emitting units are separated by the suspension structure 120, forming multiple independent and unconnected cathodes. After the cathode process is completed, no etching process is required, and the light-emitting functional layer can be directly formed on the cathode, reducing the impact of the etching process on the cathode. Especially when the cathode includes an active metal material and is relatively thin, the oxidation of the active metal and the residue problems existing in the etching process are avoided, the film interface between the cathode and the light-emitting functional layer is improved, the luminous efficiency of the light-emitting unit is improved, and the display effect of the display panel 100 is enhanced.

[0072] Figure 5 This is a schematic diagram illustrating the steps of a method for manufacturing a display panel according to another embodiment of this application. Figure 6 This is a schematic diagram illustrating the manufacturing process of a display panel according to another embodiment of this application. See also... Figures 5 to 6 As shown, specifically, step S20 includes:

[0073] S201: A cathode auxiliary electrode material is deposited on the substrate, and after patterning, cathode auxiliary electrodes are formed in the first opening region, the second opening region and the third opening region, respectively.

[0074] S202: A pixel definition layer is deposited and patterned on the cathode auxiliary electrode, two adjacent cathode auxiliary electrodes are separated by the pixel definition layer, and multiple cathode auxiliary electrodes are exposed from the second opening region, the second opening region and the third opening region respectively.

[0075] To further improve the light emission efficiency of the inverted bottom-emitting display panel, a cathode auxiliary electrode 134 is provided below the cathode. The cathode auxiliary electrode 134 can be made of a transparent metal oxide, specifically indium tin oxide (ITO) or indium zinc oxide (IZO), which have high light transmittance. This cathode auxiliary electrode 134 is also connected to the pixel active switch of the pixel driving layer 150 via a via, enabling control of the luminous intensity of the light-emitting unit. Generally, the pixel driving layer is located between the light-emitting unit and the substrate. The pixel driving layer 150 typically includes pixel driving circuitry for the light-emitting unit, such as a pixel active switch, data driving lines, and scan driving lines. The cathode of each light-emitting unit is connected to the pixel active switch via the cathode auxiliary electrode, and the cathode electrode and its switching on / off state are controlled by the data driving lines and scan driving lines.

[0076] In this embodiment, for the red light-emitting unit in the first opening region 101a, the green light-emitting unit in the second opening region 101b, and the blue light-emitting unit in the third opening region 101c, their cathode auxiliary electrodes can be formed in the same process, forming cathode auxiliary electrodes 134 in the first opening region 101a, the second opening region 101b, and the third opening region 101c, respectively. The entire cathode auxiliary electrode can be formed first using physical vapor deposition (PVD), and then protected with photoresist before photolithography etching to obtain the cathode auxiliary electrode pattern.

[0077] Specifically, step S30 includes:

[0078] S301: Sequentially deposit the conductive material and the partition material across the entire surface;

[0079] S302: The partition material in the opening area is removed by a patterning process, and a partition is formed in the non-opening area;

[0080] S303: Using the partition as a protective layer, the conductive part is etched so that the width of the conductive part is smaller than the width of the partition to form a hanging structure.

[0081] In this embodiment, before forming the bottom electrode, the conductive material and the blocking material are deposited sequentially across the entire surface to form the overhang structure. The blocking material serves as a protective layer, and the conductive material is etched using a wet etching process. Because wet etching is isotropic, even if the conductive and blocking materials use the same patterned photoresist, the lower portion of the conductive material will undergo lateral etching, resulting in a conductive material width smaller than the blocking material width. The blocking material can be etched using a dry etching process. Specifically, the conductive material can be a metallic material, such as Al, Mo, or Ag, with a thickness typically between 0.1 μm and 1.5 μm. The blocking material can be a metallic or non-metallic material, such as Ti, ITO, IZO, SiOx, SiNx, or SiOxNy, with a thickness typically between 0.03 μm and 0.2 μm. It is worth noting that the blocking capability of the overhang structure is mainly related to the thickness of the conductive material. When the overhang structure needs to block a thicker film layer, a thicker conductive material needs to be selected.

[0082] The steps in S40 include:

[0083] S401: Sequentially vapor-deposit the bottom electrode material, the first color luminescent functional layer material, and the top electrode material across the entire surface;

[0084] S402: Remove the bottom electrode material, the first color emitting functional layer material, and the top electrode material of the second opening region and the third opening region, and retain the bottom electrode material, the first color emitting functional layer material, and the top electrode material of the first opening region to form a first color emitting unit.

[0085] The steps in S50 include:

[0086] S501: Sequentially vapor-deposit the bottom electrode material, the second color luminescent functional layer material, and the top electrode material across the entire surface;

[0087] S502: Remove the bottom electrode material, the second color emitting functional layer material, and the top electrode material of the first opening region and the third opening region, and retain the bottom electrode material, the second color emitting functional layer material, and the top electrode material of the second opening region to form a second color emitting unit.

[0088] The steps in S60 include:

[0089] S601: Sequentially vapor-deposit the bottom electrode material, the third color luminescent functional layer material, and the top electrode material across the entire surface;

[0090] S602: Remove the bottom electrode material, the second color emitting functional layer material, and the top electrode material of the first opening region and the second opening region, and retain the bottom electrode material, the second color emitting functional layer material, and the top electrode material of the third opening region to form a third color emitting unit.

[0091] The top electrode of the first opening region, the top electrode of the second opening region, and the top electrode of the third opening region are electrically connected to each other through the conductive part.

[0092] In this embodiment, the cathodes, light-emitting functional layers, and top electrodes of adjacent light-emitting units are separated by a pendant structure, thereby forming multiple isolated light-emitting units. In this scheme, during the formation of light-emitting units in different opening areas, the deposition angle of the cathode needs to be controlled to prevent the cathode from contacting the conductive parts of the pendant structure, thus preventing electrical crosstalk caused by contact between the cathode and the pendant structure. The anode, however, needs to contact the conductive parts in the pendant structure, so that the anodes of adjacent light-emitting units are connected through conductive parts, forming a fully electrically connected mesh anode, thereby overcoming problems such as impedance drop.

[0093] It is worth mentioning that the formation of the first, second, and third color emitting functional layers involves sequentially vacuum-depositing an electron injection layer, an electron transport layer, a hole blocking layer, a emitting layer, an electron blocking layer, a hole transport layer, and a hole injection layer. In this embodiment, the full-surface deposition process mainly employs vacuum evaporation technology. Throughout the entire vacuum evaporation process, the cathode, emitting functional layer, and anode are formed in a vacuum environment isolated from water and oxygen, avoiding the possibility of oxidation and other degradation of the metal film, improving the stability and consistency of the metal cathode and anode, and thus increasing the fabrication yield of the OLED emitting unit.

[0094] In the above process steps, after completing the first color light-emitting unit process, the first color light-emitting unit needs to be protected, i.e., an etching protection layer 135 is provided to remove redundant first color light-emitting units, thereby forming light-emitting units of the corresponding color in the corresponding opening regions. Before step S401, an etching protection layer is also formed on the top electrode material of the first opening region. After completing the second color light-emitting unit process, redundant material of the second color light-emitting units on the first and second opening regions is removed by providing an etching protection layer 135 at the second opening region position. Before step S501, an etching protection layer is also formed on the top electrode material of the second opening region. The formation process of the third color light-emitting unit is similar, and before step S601, an etching protection layer is also formed on the top electrode material of the third opening region.

[0095] Figure 7 This is a schematic diagram of the display device of this application, see [link / reference]. Figure 7 As shown, this application also discloses a display device, the display device 200 including a driving circuit 210 and a display panel 100 in the above embodiments, wherein the driving circuit 210 is used to drive the display panel 100 to display.

[0096] In this application, when forming the bottom electrode of the light-emitting unit, a suspended structure is used to separate the bottom electrodes of multiple light-emitting units, forming multiple independent and unconnected bottom electrodes. After completing the bottom electrode fabrication process, no etching process is required, and the light-emitting functional layer of the light-emitting unit can be directly formed on the bottom electrode, reducing the impact of the etching process on the bottom electrode. Especially when the bottom electrode includes an active metal material, the oxidation of the active metal and the residue problems existing in the etching process are avoided, improving the film interface between the bottom electrode and the light-emitting functional layer, improving the luminous efficiency of the light-emitting unit, and enhancing the display effect of the display panel.

[0097] It should be noted that the inventive concept of this application can form many embodiments, but due to the limited space of the application documents, they cannot all be listed. Therefore, without conflict, the embodiments described above or the technical features can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effect will be enhanced.

[0098] The above description, in conjunction with specific optional embodiments, provides a further detailed explanation of this application and should not be construed as limiting the specific implementation of this application to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of this application, and all such modifications or substitutions should be considered within the scope of protection of this application.

Claims

1. A method for manufacturing a display panel, characterized in that, The method comprises the steps of: providing a substrate; forming a pixel definition layer on the substrate and patterning the pixel definition layer to form a plurality of opening regions, wherein the opening regions comprise a first opening region, a second opening region and a third opening region, and the method comprises the steps of: depositing a cathode auxiliary electrode material on the substrate, and patterning the cathode auxiliary electrode material to form a cathode auxiliary electrode in the first opening region, the second opening region and the third opening region; depositing and patterning a pixel definition layer on the cathode auxiliary electrode, and separating two adjacent cathode auxiliary electrodes by the pixel definition layer, and exposing the cathode auxiliary electrode from the second opening region, the second opening region and the third opening region, respectively; forming a overhang structure on the pixel definition layer, which comprises the steps of: sequentially depositing a whole surface of a conductive part material and a partition part material; removing the partition part material in the opening region by a patterning process to form a partition part in a non-opening region; and etching the conductive part with the partition part as a protection layer, so that the width of the conductive part is smaller than the width of the partition part to form the overhang structure; sequentially depositing a bottom electrode material, a first color light emitting functional layer material and a top electrode material on a whole surface; removing the bottom electrode material, the first color light emitting functional layer material and the top electrode material in the second opening region and the third opening region, and retaining the bottom electrode material, the first color light emitting functional layer material and the top electrode material in the first opening region to form a first color light emitting unit; sequentially depositing a bottom electrode material, a second color light emitting functional layer material and a top electrode material on a whole surface; removing the bottom electrode material, the second color light emitting functional layer material and the top electrode material in the first opening region and the third opening region, and retaining the bottom electrode material, the second color light emitting functional layer material and the top electrode material in the second opening region to form a second color light emitting unit; sequentially depositing a bottom electrode material, a third color light emitting functional layer material and a top electrode material on a whole surface; removing the bottom electrode material, the second color light emitting functional layer material and the top electrode material in the first opening region and the second opening region, and retaining the bottom electrode material, the second color light emitting functional layer material and the top electrode material in the third opening region to form a third color light emitting unit; the top electrode of the first opening region, the top electrode of the second opening region and the top electrode of the third opening region are electrically connected to each other through the conductive part; wherein the bottom electrode of the first color light emitting unit, the bottom electrode of the second color light emitting unit and the bottom electrode of the third color light emitting unit are separated by the overhang structure, the top electrode is an anode, and the bottom electrode is a cathode.

2. The manufacturing method of a display panel according to claim 1, wherein The bottom electrode of the first color light emitting unit, the bottom electrode of the second color light emitting unit and the bottom electrode of the third color light emitting unit are formed by using the same material in different processes.

3. The manufacturing method of a display panel according to claim 1, wherein Before the step of removing the bottom electrode material, the first color light emitting functional layer material and the top electrode material in the second opening region and the third opening region, the method further comprises the steps of: forming an etching protection layer on the top electrode material in the first opening region; and before the step of removing the bottom electrode material, the second color light emitting functional layer material and the top electrode material in the first opening region and the third opening region, the method further comprises the steps of: forming an etching protection layer on the top electrode material of the second opening area; The method further comprises, before the step of removing the bottom electrode material, the second color light emitting functional layer material and the top electrode material of the first opening area and the second opening area: forming an etching protection layer on the top electrode material of the third opening area.

4. The manufacturing method of a display panel according to claim 1, wherein The bottom electrode is a light-transmitting electrode formed by one or both of magnesium material and silver material, and the top electrode is formed by a reflective metal material.

5. The manufacturing method of the display panel according to claim 4, wherein the thickness of the bottom electrode is greater than or equal to 100 angstrom and less than or equal to 300 angstrom. The first color light emitting functional layer, the second color light emitting functional layer and the third color light emitting functional layer each comprise an electron transport layer and a hole transport layer, the electron transport layer is arranged on the side close to the cathode, the hole transport layer is arranged on the side close to the anode, the electron transport layer is arranged on the cathode, the hole transport layer is arranged on the electron transport layer, and the anode is arranged on the hole transport layer. ​

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