Manufacturing method of display panel, display panel and display device

Abstract

The invention discloses a manufacturing method of a display panel, the 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 suspension 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 the plurality of first opening areas 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 in the plurality of second opening areas to form a second color light-emitting unit; and sequentially depositing a bottom electrode material, a third color light-emitting functional layer material and a top electrode material in the plurality of third opening areas to form a third color light-emitting unit. 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 method for manufacturing a display panel, a display panel 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 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 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 method for manufacturing a display panel, comprising the steps of:

[0006] Providing a substrate;

[0007] Forming a pixel definition layer on the base substrate, and patterning the pixel definition layer to form a plurality of opening areas, wherein the opening areas include a first opening area, a second opening area, and a third opening area;

[0008] forming an overhang structure on the pixel definition layer;

[0009] Depositing a bottom electrode material, a first color light-emitting functional layer material and a top electrode material in sequence in the plurality of the first opening regions to form a first color light-emitting unit;

[0010] Depositing a bottom electrode material, a second color light-emitting functional layer material and a top electrode material in sequence in the plurality of the second opening regions to form a second color light-emitting unit; and

[0011] Depositing a bottom electrode material, a third color light-emitting functional layer material and a top electrode material in sequence in the plurality of third opening regions to form a third color light-emitting unit;

[0012] 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 overhanging 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 are formed in different processes.

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

[0015] Depositing cathode auxiliary electrode material on the base substrate, and forming cathode auxiliary electrodes in the first opening area, the second opening area and the third opening area respectively after patterning;

[0016] 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 a plurality of cathode auxiliary electrodes are exposed from the second opening area, the second opening area and the third opening area respectively.

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

[0018] Depositing the conductive part material and the partition part material on the entire surface in sequence;

[0019] Removing the partition material in the opening area by a patterning process to form a partition in the non-opening area;

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

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

[0022] Sequentially vapor-depositing a bottom electrode material, a first color light-emitting functional layer material, and a top electrode material on the entire surface;

[0023] Removing the bottom electrode material, the first color light-emitting functional layer material and the top electrode material of the second opening area and the third opening area, and retaining the bottom electrode material, the first color light-emitting functional layer material and the top electrode material of the first opening area to form a first color light-emitting unit;

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

[0025] Sequentially vapor-depositing a bottom electrode material, a second color light-emitting functional layer material, and a top electrode material on the entire surface;

[0026] 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 third opening area, and retaining the bottom electrode material, the second color light-emitting functional layer material and the top electrode material of the second opening area to form a second color light-emitting unit;

[0027] The step of sequentially depositing a bottom electrode material, a third color light-emitting functional layer material and a top electrode material in the plurality of third opening regions to form a third color light-emitting unit comprises:

[0028] Sequentially vapor-depositing a bottom electrode material, a third color light-emitting functional layer material, and a top electrode material on the entire surface;

[0029] 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, and retaining the bottom electrode material, the second color light-emitting functional layer material and the top electrode material of the third opening area to form a third color light-emitting unit;

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

[0031] Optionally, 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 area and the third opening area, the step further includes:

[0032] forming an etching protection layer on the top electrode material in the first opening area;

[0033] 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 area and the third opening area, the following steps are further included:

[0034] forming an etching protection layer on the top electrode material in the second opening area;

[0035] 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 area and the second opening area, the following steps are further included:

[0036] An etching protection layer is formed on the top electrode material in 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 respectively include a bottom electrode and a top electrode, the top electrode is an anode, and the bottom electrode is a cathode; the bottom electrode is a light-transmitting electrode, formed of one or both of a magnesium material and a silver material, and the top electrode is formed of 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 luminescent functional layer, the second color luminescent functional layer and the third color luminescent functional layer respectively include 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.

[0039] The present application also discloses a display panel formed by the manufacturing method of the display panel as described above, wherein the display panel includes a base substrate, a pixel definition layer, an overhang 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 arranged on the base substrate and is formed with a plurality of opening areas, the opening areas include a first opening area, a second opening area and a third opening area; the overhang structure is arranged on the pixel definition layer and is located in a non-opening area; the first color light-emitting unit is arranged in the first opening area; the second color light-emitting unit is arranged in the second opening area; the third color light-emitting unit is arranged in the third opening area; 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.

[0040] 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.

[0041] In the present application, when forming the bottom electrode of the light-emitting unit, the bottom electrodes of the plurality of light-emitting units are separated by a suspension structure to form a plurality of independent and unconnected bottom electrodes. After the bottom electrode manufacturing process is completed, the light-emitting functional layer of the light-emitting unit can be directly formed on the bottom electrode without the need for an etching process, thereby 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 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

[0042] 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:

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

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

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

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

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

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

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

[0050] Among them, 100, display panel; 101, opening area; 101a, first opening area; 101b, second opening area; 101c, second opening area; 102, non-opening area; 110, substrate; 111, pixel definition layer; 120, overhang structure; 121, conductive part; 122, partition part; 130R, first color light-emitting unit; 130G, second color light-emitting unit; 130B, third color 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, etching protection layer; 150, pixel driving layer; 200, display device; 210, driving circuit. DETAILED DESCRIPTION

[0051] 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.

[0052] 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.

[0053] The present application is described in detail below with reference to the accompanying drawings and optional embodiments.

[0054] Figure 1 is a schematic diagram of the steps of the method for manufacturing the display panel of the present application, Figure 2 is a schematic diagram of the manufacturing process of the display panel of this application, see Figure 1 to Figure 2 As shown, the present application discloses a method for manufacturing a display panel, comprising the steps of:

[0055] S10: providing a substrate;

[0056] S20: forming a pixel definition layer on the base substrate, and patterning the pixel definition layer 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: forming an overhang structure on the pixel definition layer;

[0058] S40: depositing a bottom electrode material, a first color light-emitting functional layer material and a top electrode material in sequence in the plurality of first opening regions to form a first color light-emitting unit;

[0059] S50: depositing a bottom electrode material, a second color light-emitting functional layer material and a top electrode material in sequence in the plurality of the second opening regions to form a second color light-emitting unit; and

[0060] S60: depositing a bottom electrode material, a third color light-emitting functional layer material and a top electrode material in sequence in the plurality of third opening regions to form a third color light-emitting unit;

[0061] 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 overhanging structure.

[0062] In the present application, when forming the bottom electrode of the light-emitting unit, the bottom electrodes of the plurality of light-emitting units are separated by a suspension structure to form a plurality of independent and unconnected bottom electrodes. After the bottom electrode manufacturing process is completed, the light-emitting functional layer of the light-emitting unit can be directly formed on the bottom electrode without the need for an etching process, thereby 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 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.

[0063] Among them, the first color light-emitting unit can be a red light-emitting unit, and the light emitted is red light; the second color light-emitting unit can be a green light-emitting unit, and the light emitted is green light; the third color light-emitting unit can be a blue light-emitting unit, and the light emitted is blue light. The main difference between the red light-emitting unit, the green light-emitting unit and the blue light-emitting unit is that there is a difference in the materials in the light-emitting functional layer, so that light-emitting units of different colors emit light of different colors under the excitation of holes and electrons.

[0064] It is understandable that the process sequence of the red light-emitting unit, the green light-emitting unit and the blue light-emitting unit of the present application is not limited, and the light-emitting unit of any color can be selected for processing first, and then the light-emitting units of other colors are formed in sequence. Of course, the color of the light-emitting unit of the present application is not limited to the above-mentioned red, green and blue, for example, white, yellow and other light-emitting units are also applicable. For the first opening area, the second opening area and the third opening area, they are distinguished only by the light-emitting color of the light-emitting unit in the opening area. The light-emitting units of the same color are arranged in multiple first opening areas, and the order, size, etc. of the opening areas are not limited by "first", "second" and "third".

[0065] Figure 3 is a schematic diagram of the display panel of the present application, see Figure 3As shown, the present application also discloses a display panel 100, the display panel 100 is formed by the manufacturing method of the display panel 100, the display panel 100 includes a base substrate 110, a pixel definition layer 111, an overhang 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 arranged on the base substrate 110, and a plurality of opening areas 101 are formed, the opening area 101 includes a first opening area 101a, a second opening area 101b and a third opening area 101c; the overhang structure 120 0 is arranged on the pixel definition layer 111 and is located in the non-opening area 102; the first color light-emitting unit 130R is arranged in the first opening area 101a; the second color light-emitting unit 130G is arranged in the second opening area 101b; the third color light-emitting unit 130B is arranged 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 overhang structure 120; the overhang structure 120 includes a conductive portion 121 and a partition portion 122.

[0066] Figure 4 is a schematic diagram of an inverted light-emitting unit of the present application, see Figure 4As shown, the light-emitting unit in this embodiment is an inverted organic light-emitting unit, wherein 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, and the third color light-emitting unit 130B includes a bottom electrode, a third color light-emitting functional layer and a top electrode, and 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, and the difference between them mainly lies in that the light-emitting layer materials are different, while the film layer structures are all consistent, with a basic film layer of the 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, 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. 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. The electron transport layer 1321 in this embodiment is connected to the cathode 133 through an electron injection layer 1324, and a hole blocking layer 1325 is also arranged 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 also provided between the hole transport layer 1323 and the 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 the present application can adopt top emission or bottom emission technology. When the bottom emission technology is selected, it is necessary to make the cathode below transparent and the anode above have high reflectivity. When the inverted organic light-emitting unit in this embodiment is a bottom emission type light-emitting unit, it has better light extraction efficiency. At this time, the light emission direction is from the cathode to the direction of the substrate 110, so as to realize light emission display from the back of the substrate 110. Relatively speaking, the light emission efficiency of the light-emitting unit in the inverted bottom emission display panel 100 is affected by the work function of the cathode and the anode. Generally speaking, 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 a higher light emission efficiency. However, when the anode is selected as a reflective electrode and the cathode is selected as a transparent electrode, the work function of the anode will be reduced and the work function of the cathode will be increased, resulting in the problem of low light emission efficiency of the inverted bottom emission display panel 100.

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

[0069] Specifically, the bottom electrode of the present application is a cathode, and the bottom electrode material is formed of one or both of a magnesium material and a silver material, and the top electrode is formed of a reflective metal material. It can be 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 include a bottom electrode and a top electrode, respectively, and the bottom electrode and top electrode materials used in the light-emitting units of different colors are respectively consistent. In the subsequent description, the definitions of the bottom electrode and the top electrode are respectively applicable to the light-emitting units of different colors, and will not be repeated here.

[0070] Of course, this embodiment is also applicable to the case 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 light emitting units of the same color, such as white light emitting units. In this case, the bottom electrodes can be formed at the same time, that is, formed in the same process. For different colors, such as the first color light emitting unit 130R can be a red light emitting unit, the second color light emitting unit 130G can be a green light emitting unit, and the third color light emitting unit 130B can be a blue light emitting unit, the bottom electrodes of three different colors can be formed in different processes, that is, after the cathode, red light emitting functional layer and anode of the red light emitting unit are completed, after the cathode, green light emitting functional layer and anode of the green light emitting unit are completed, the cathode, blue light emitting functional layer and anode of the blue light emitting unit are finally formed, thereby completing the processes of the light emitting units in sequence.

[0071] When the cathode is formed of one or both of magnesium and silver materials, two aspects need to be considered. The first aspect is the light transmittance of the metal material. The light transmittance of the metal is related to its lattice. The lattice structure 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 opaque properties. 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 transparent. 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 as an example of an active metal material, such as magnesium or silver, the thickness of the cathode 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 relatively thin, for example, 100 angstroms to 300 angstroms, oxidation is likely to occur 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, thereby causing the inverted bottom-emitting display panel 100 to have a low luminous efficiency. Therefore, when forming the cathode of the light-emitting unit, the overhanging structure 120 is used to separate the cathodes of multiple light-emitting units to form multiple independent and unconnected cathodes. After the cathode process is completed, there is no need to use an etching process, and the light-emitting functional layer can be directly formed on the cathode, reducing the impact of the etching process on the cathode. In particular, when the cathode includes an active metal material and is relatively thin, oxidation of the active metal and residual problems in etching are avoided, the film interface between the cathode 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 100 is improved.

[0072] Figure 5 is a schematic diagram of steps of a method for manufacturing a display panel according to another embodiment of the present application, Figure 6 is a schematic diagram of the manufacturing process of a display panel according to another embodiment of the present application, see Figures 5 and 6 As shown, specifically, the step S20 includes:

[0073] S201: depositing a cathode auxiliary electrode material on the substrate, and forming cathode auxiliary electrodes in the first opening area, the second opening area, and the third opening area after patterning;

[0074] S202: depositing and patterning a pixel definition layer on the cathode auxiliary electrode, wherein two adjacent cathode auxiliary electrodes are separated by the pixel definition layer, and a plurality of cathode auxiliary electrodes are exposed from the second opening region, the second opening region, and the third opening region, respectively.

[0075] In order to further improve the light extraction efficiency of the inverted bottom-emitting display panel, a cathode auxiliary electrode 134 is provided under the cathode. The material of the cathode auxiliary electrode 134 may be a transparent metal oxide, wherein the transparent metal oxide may be formed of an indium tin oxide material (ITO) or an indium zinc oxide material (IZO), and such materials have high light transmittance. The cathode auxiliary electrode 134 is also connected to the pixel active switch of the pixel driving layer 150 through a via hole to control the light intensity of the light-emitting unit. Generally, the pixel driving layer is provided between the light-emitting unit and the substrate. The pixel driving layer 150 generally includes a pixel driving circuit of the light-emitting unit, such as a pixel active switch, a data driving line, a scanning driving line, etc. The cathode of each light-emitting unit is connected to the pixel active switch through the cathode auxiliary electrode, and the cathode electrode is controlled and turned off through the data driving line and the scanning driving line.

[0076] In this embodiment, for the red light emitting unit in the first opening area 101a, the green light emitting unit in the second opening area 101b, and the blue light emitting unit in the third opening area 101c, the cathode auxiliary electrodes can be formed in the same process, and the cathode auxiliary electrodes 134 are formed in the first opening area 101a, the second opening area 101b, and the third opening area 101c, respectively. Physical vapor deposition (PVD) can be used to form the entire surface of the cathode auxiliary electrode, and then photolithography and etching are performed after photoresist protection to obtain the cathode auxiliary electrode pattern.

[0077] Specifically, the step S30 includes:

[0078] S301: depositing the conductive part material and the partition part material on the entire surface in sequence;

[0079] S302: removing the partition material in the opening area by a patterning process, and forming a partition in the non-opening area;

[0080] S303: 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.

[0081] In this embodiment, the step of forming the overhang structure is to deposit the conductive part material and the partition part material on the entire surface in sequence before forming the bottom electrode, and use the partition part as a protective layer to etch the conductive part using a wet etching process. Since the wet etching process is isotropic, even if the conductive part and the partition part use the same pattern of photoresist, the lower part of the conductive part will be side-etched, so that the width of the conductive part is smaller than the width of the partition part. Among them, the etching of the partition part material can be selected as a dry etching process. In terms of specific materials, the conductive part material can be a metal material, such as Al, Mo, Ag and other metals, and the thickness is generally between 0.1um and 1.5um. The partition part can be made of metal or non-metal materials, such as Ti, ITO, IZO, SiOx, SiNx, SiOxNy and other materials, and the thickness is generally between 0.03um and 0.2um. It is worth mentioning that the isolation ability of the overhang structure is mainly related to the thickness of the conductive part. When the film layer that the overhang structure needs to isolate is thicker, a thicker conductive part needs to be selected.

[0082] The steps of S40 include:

[0083] S401: sequentially vapor-depositing a bottom electrode material, a first color light-emitting functional layer material, and a top electrode material on the entire surface;

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

[0085] The steps of S50 include:

[0086] S501: sequentially vapor-depositing a bottom electrode material, a second color light-emitting functional layer material, and a top electrode material on the entire surface;

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

[0088] The steps of S60 include:

[0089] S601: sequentially vapor-depositing a bottom electrode material, a third color light-emitting functional layer material, and a top electrode material on the entire surface;

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

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

[0092] In this embodiment, the cathode, light-emitting functional layer and top electrode of adjacent light-emitting units are separated by the overhang structure, thereby forming a plurality of isolated light-emitting units. In this solution, when evaporating the cathode in the process of forming the light-emitting units in different opening areas, it is necessary to control the evaporation angle so that the cathode does not contact the conductive part of the overhang structure, thereby preventing the cathode from contacting the overhang structure and causing electrical crosstalk. The anode needs to contact the conductive part in the overhang structure, so that the anodes of adjacent light-emitting units are connected through the conductive part, thereby forming a mesh anode that is electrically connected on the entire surface, thereby overcoming problems such as resistance drop.

[0093] It is worth mentioning that when forming the first color light-emitting functional layer, the second color light-emitting functional layer and the third color light-emitting functional layer, it includes sequentially vacuum-depositing an electron injection layer, an electron transport layer, a hole blocking layer, a light-emitting layer, an electron blocking layer, a hole transport layer and a hole injection layer. In this embodiment, the vacuum evaporation technology mainly used in the whole surface deposition process, during the whole vacuum evaporation process, the cathode, the light-emitting functional layer and the 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 improving the production yield of the OLED light-emitting unit.

[0094] In the above process steps, after completing the process of the first color light-emitting unit, it is also necessary to protect the first color light-emitting unit, that is, to set an etching protection layer 135, and remove the redundant first color light-emitting units, so that the corresponding color light-emitting units are formed in the corresponding opening area. Before the step of S401, it also includes forming an etching protection layer on the top electrode material of the first opening area. After completing the process of the second color light-emitting unit, by setting the etching protection layer 135 at the position of the second opening area, the redundant materials of the second color light-emitting unit on the first opening area and the second opening area are removed. Before the step of S501, it also includes forming an etching protection layer on the top electrode material of the second opening area. The formation process of the third color light-emitting unit is also similar, and before the step of S601, it also includes forming an etching protection layer on the top electrode material of the third opening area.

[0095] 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, wherein the display device 200 includes a driving circuit 210 and the display panel 100 in the above embodiment, wherein the driving circuit 210 is used to drive the display panel 100 to display.

[0096] In the present application, when forming the bottom electrode of the light-emitting unit, the bottom electrodes of the plurality of light-emitting units are separated by a suspension structure to form a plurality of independent and unconnected bottom electrodes. After the bottom electrode manufacturing process is completed, the light-emitting functional layer of the light-emitting unit can be directly formed on the bottom electrode without the need for an etching process, thereby 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 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.

[0097] 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.

[0098] The above content is a further detailed description 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 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, wherein the opening areas include a first opening area, a second opening area, and a third opening area; forming an overhang structure on the pixel definition layer; Depositing a bottom electrode material, a first color light-emitting functional layer material and a top electrode material in sequence in the plurality of the first opening regions to form a first color light-emitting unit; Depositing a bottom electrode material, a second color light-emitting functional layer material and a top electrode material in sequence in the plurality of the second opening regions to form a second color light-emitting unit; and Depositing a bottom electrode material, a third color light-emitting functional layer material and a top electrode material in sequence in the plurality of third opening regions to form a third color light-emitting unit; 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 overhanging structure.

2. The method for manufacturing a display panel according to claim 1, characterized in that: 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 are formed in different processes.

3. The method for manufacturing a display panel according to claim 1, wherein: The step of forming a pixel definition layer on the base substrate and patterning the pixel definition layer to form a plurality of opening areas comprises: Depositing cathode auxiliary electrode material on the base substrate, and forming cathode auxiliary electrodes in the first opening area, the second opening area and the third opening area respectively after patterning; 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 a plurality of cathode auxiliary electrodes are exposed from the second opening area, the second opening area and the third opening area respectively.

4. The method for manufacturing a display panel according to claim 3, characterized in that: The step of forming an overhang structure on the pixel definition layer includes: Depositing the conductive part material and the partition part material on the entire surface in sequence; Removing the partition material in the opening area by a patterning process to form a partition in the non-opening area; The partition portion is used as a protective layer, and the conductive portion is etched so that the width of the conductive portion is smaller than the width of the partition portion to form a hanging structure.

5. The method for manufacturing a display panel according to claim 4, characterized in that: The step of sequentially depositing a bottom electrode material, a first color light-emitting functional layer material and a top electrode material in the plurality of first opening regions to form a first color light-emitting unit comprises: Sequentially vapor-depositing a bottom electrode material, a first color light-emitting functional layer material, and a top electrode material on the entire surface; Removing the bottom electrode material, the first color light-emitting functional layer material and the top electrode material of the second opening area and the third opening area, and retaining the bottom electrode material, the first color light-emitting functional layer material and the top electrode material of the first opening area to form a first color light-emitting unit; The step of sequentially depositing a bottom electrode material, a second color light-emitting functional layer material and a top electrode material in the plurality of second opening regions to form a second color light-emitting unit comprises: Sequentially vapor-depositing a bottom electrode material, a second color light-emitting functional layer material, and a top electrode material on the entire surface; 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 third opening area, and retaining the bottom electrode material, the second color light-emitting functional layer material and the top electrode material of the second opening area to form a second color light-emitting unit; The step of sequentially depositing a bottom electrode material, a third color light-emitting functional layer material and a top electrode material in the plurality of third opening regions to form a third color light-emitting unit comprises: Sequentially vapor-depositing a bottom electrode material, a third color light-emitting functional layer material, and a top electrode material on the entire surface; 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, and retaining the bottom electrode material, the second color light-emitting functional layer material and the top electrode material of the third opening area to form a third color light-emitting unit; The top electrode in the first opening region, the top electrode in the second opening region, and the top electrode in the third opening region are electrically connected to each other through the conductive portion.

6. The method for manufacturing a display panel according to claim 5, characterized in that: 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 area and the third opening area, the following steps are further included: forming an etching protection layer on the top electrode material in the first opening area; 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 area and the third opening area, the following steps are further included: forming an etching protection layer on the top electrode material in the second opening area; 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 area and the second opening area, the following steps are further included: An etching protection layer is formed on the top electrode material in the third opening region.

7. The method for manufacturing a display panel according to claim 5, characterized in that: The first color light-emitting unit, the second color light-emitting unit and the third color light-emitting unit respectively include a bottom electrode and a top electrode, the top electrode is an anode, and the bottom electrode is a cathode; the bottom electrode is a light-transmitting electrode, formed of one or both of magnesium material and silver material, and the top electrode is formed of a reflective metal material.

8. The method for manufacturing a display panel according to claim 7, 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; The first color luminescent functional layer, the second color luminescent functional layer and the third color luminescent functional layer respectively include an electron transport layer and a hole transport layer, the electron transport layer is arranged on a side close to the cathode, the hole transport layer is arranged on a 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.

9. A display panel formed by the method for manufacturing a display panel according to any one of claims 1 to 8, characterized in that: The display panel comprises: substrate substrate; A pixel definition layer is disposed on the base substrate and is formed with a plurality of opening areas, wherein the opening areas include a first opening area, a second opening area and a third opening area; The overhang structure is disposed on the pixel definition layer and is located in the non-opening area; A first color light emitting unit, arranged in the first opening area; A second color light emitting unit, disposed in the second opening area; and A third color light emitting unit is arranged in the third opening area; 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 overhanging structure.

10. A display device, characterized in that: It comprises a driving circuit and the display panel according to any one of claims 1 to 9, wherein the driving circuit is used to drive the display panel to display.

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